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News Article | February 15, 2017
Site: www.chromatographytechniques.com

Editor's note: This is part two of a two-article series on breathomics, as published in the February print issue of Laboratory Equipment. Researchers and doctors have long investigated the connection between a person’s state of being and their exhaled breath. In the 1800s, Francis Anstie observed that small amounts of alcohol were excreted in breath—long before Robert Frank Borkenstein used chemical oxidation and photometry to power his breath analyzer for alcohol concentrations, which would become law enforcement’s standard. Fast forward to 2017 and breath research—or breathomics, as its now called—is just as important as ever. The field is a combination of breath and metabolomics, the study of unique chemical fingerprints that specific cellular processes leave behind. Once relegated to the lab due to the mass spectrometric techniques that traditionally power breathomic tests, the field is now emerging for some fresh air, with researchers increasingly developing portable breathomic devices for everything from diabetes and cancer to marijuana intoxication. “The field is already making headway in early diagnosis of cancer and other medical applications,” Tara Lovestead, a NIST researcher working in the field, told Laboratory Equipment. “The potential for testing for chronic disease, inflammation and cancer is very tangible. As applied to law enforcement, a breath signature for intoxication could eliminate the need to know the actual avenue for becoming intoxicated.” It’s relatively easy to single out an individual that is driving under the influence of alcohol. Swerving between lanes, running red lights and inconsistent speed are signs easily identifiable to passersby and police alike. Once suspicions are raised (or even before that), police can rely on the accuracy of their portable breathalyzer to identify the exact amount of blood alcohol content in said driver—providing unequivocal confirmation of the presence of alcohol. But how do police spot a driver who is driving “high,” or under the influence of marijuana? He or she may be showing signs similar to a drunk driver, but not necessarily since the effects of marijuana in large doses dramatically differs from the effects of alcohol. Each state has its own laws regarding the blood alcohol level of drivers in terms of what is considered legal and what is considered legally drunk, or under the influence. And now, with more states legalizing both medical and recreational marijuana, legal limits are being set in this arena as well. However, they are not as clear as drunk driving laws—which is more a function of the vice than the law itself. Unlike alcohol, THC—the active compound in marijuana that leads to a high—can stay in a user’s blood, saliva or urine for minutes, days, hours or even months depending on what strain of marijuana is used, how often, and the specific method of ingestion. “There are just so many questions we need to address, and so much we don’t know,” said Lovestead, a chemical engineer at NIST. “The biggest issue for law enforcement is Δ9-THC in the blood does not correspond to intoxication.” At the Forensics@NIST conference in November, Lovestead gave a presentation describing her work to identify other chemical markers indicative of marijuana intoxication. She is focused on creating noninvasive, portable breath tests for Δ9-THC that can indicate recent marijuana usage from 30 minutes to 2 hours prior—the only real way to determine if a user is driving under the influence of marijuana. Lovestead said her team’s approach incorporates three key areas: fundamental data; materials development; and breatholomics (a subset of breathomics). Chemistry-wise, there is still a lot researchers do not know about cannabis, THC and other cannabinoids. So, part of Lovestead’s research is to research. She and her team are measuring vapor pressure, molecular interactions and partition co-efficients to successfully apply it to overall cannabis research. They are also researching and/or developing new materials to outfit a potential marijuana breathalyzer device, especially in terms of what is best suited to crucial absorption and desorption techniques. Lovestead is also paving a way toward determining the chemical signature of marijuana intoxication. To do so, she has thus far relied on a dynamic headspace sampling technique called porous layer open tubular (PLOT)-cryoadsorption that has provided extremely sensitive quantitative recovery of Δ9-THC. The method highly decreases the amount of time expended to identify vapor pressure information. Most importantly, Lovestead and her team have adapted the technology to create a portable version that could ultimately be used at the roadside. For breath collection, Lovestead relies on capillary microextraction of volatiles. This method is already ready for in-the-field sampling, and is most suited for the breath collection of cannabis-related metabolites, which indicate if a user actually smoked marijuana or just ingested it secondhand. “[Fundamental data, materials development and breatholomics] build upon one other and help the other out,” Lovestead said about her lab’s three-fold approach to a marijuana breath test. “In the future, we are going to look at more artificial breath work with the different materials available.”


Using fragments of radioactive glass picked up from the site of the first nuclear bomb explosion in the United States, scientists are trying to explain the mystery behind the formation of the moon and the properties of lunar rocks. The study by researchers from the Scripps Institution of Oceanography at the University of California, San Diego used materials from the Trinity test site in New Mexico to show that the explosion could be similar to a collision between proto-Earth and a Mars-sized object 4.5 billion years ago. The current theory on moon formation is that a Mars-sized object called Theia bombarded the Earth and the ejected mass converged to form the moon. The impact would have produced massive amounts of extreme heat that drove volatile compounds out of the space rocks that formed the moon. The scientists set out to prove how moon formation could be caused by high-temperature processes by analyzing the nuclear test site residue, which was formed from the same conditions as the planetary collision. In the extreme heat of the blast on July 16, 1945, the top layer of the sandy soil melted into a green silicate glass. The radioactive glass, which was given the name trinitite, was spread across a radius of 1,150 feet from the detonation point. For the study, James Day, director of the Scripps Geochemistry Isotope Laboratory, and team studied trinitite samples from various locations and depths ranging from within an average of 30 feet to 800 feet within ground zero. Day and colleagues found that trinitites from the nuclear test site were short on volatile compounds such as zinc and water. The team chose to analyze zinc isotopes because zinc boils off in extreme heat, such as that generated by the supposed collision that formed the moon. Based on the analysis, the trinitite samples obtained nearer to ground zero carried less zinc than samples from farther away. Also, the zinc that was left only had heavy isotopes, which do not normally evaporate. The deprivation of volatiles from the samples, especially in trinitites close to the site of the explosion, was the result of vaporization under high temperature, the researchers said. "The results show that evaporation at high temperatures, similar to those at the beginning of planet formation, leads to the loss of volatile elements and to enrichment in heavy isotopes in the leftover materials from the event," said Day. He said the theory has now been backed up by experimental evidence. Their findings led the researchers to believe that the mighty collision must have been a high-temperature event and that evaporated most volatiles, like what happened with the trinitite samples in the nuclear test site. Day said the new study has given them the confidence that they're going in the right direction in terms of interpreting the data on the lunar rock samples brought home by the Apollo astronauts. The lunar samples also have the same volatile-loss signatures as trinitite. © 2017 Tech Times, All rights reserved. Do not reproduce without permission.


News Article | February 17, 2017
Site: globenewswire.com

«En 2016, Essilor a réalisé une nouvelle année de croissance de ses résultats, poursuivi sa mission d'amélioration de la vue dans le monde et élargi son champ d'activité au sein de ses métiers et dans de nouveaux territoires. Nous commençons 2017 avec une direction et une organisation opérationnelle renforcées pour saisir plus efficacement encore les opportunités de croissance du vaste marché de l'optique. De nombreuses initiatives en termes d'innovation et de développement de nos gammes de produits et services sont d'ores et déjà en cours. Nous en attendons une accélération progressive de la croissance au fil de l'année. Au-delà, le rapprochement proposé avec le groupe Luxottica et l'intégration qu'il permettrait entre verres, montures et distribution ouvrent de nouvelles perspectives particulièrement enthousiasmantes », a déclaré Hubert Sagnières, Président-Directeur Général du groupe. En 2016, Essilor a continué à apporter des réponses, toujours plus nombreuses, aux besoins visuels non satisfaits en poursuivant sa stratégie d'élargissement de son champ d'activité dans les verres correcteurs, le Solaire et les ventes en ligne. Cette stratégie, fondée sur l'innovation, le marketing consommateur et les partenariats s'est traduite par le lancement de nombreux nouveaux produits et l'engagement d'environ 209 millions d'euros de dépenses média pour renforcer les marques du groupe auprès des consommateurs. Dans les verres correcteurs, le groupe a poursuivi son expansion dans de nouveaux territoires. De plus, la croissance générée par les nouveaux produits, les campagnes média, les offres de logistique intégrées et les acquisitions ont plus que compensé les aléas de marché dans certaines régions du monde (notamment aux Etats-Unis, au Brésil et au Moyen-Orient). Perspectives En 2017, Essilor va progressivement accentuer le déploiement de l'innovation et lancer, au cours des prochains dix-huit mois, plusieurs produits importants sous ses trois marques principales de verres correcteurs : Varilux®, Crizal® et Transitions®. De plus, le groupe va accélérer le développement de ses activités dans le Solaire et la vente de produits optiques par internet, en capitalisant sur les interconnexions entre les gammes de produits, l'expansion géographique et la complémentarité avec les acquisitions récentes. Le renforcement de la direction et de l'organisation opérationnelle du groupe apportera une plus grande réactivité et une meilleure efficacité à la mise en oeuvre de la stratégie. Ainsi, Essilor prévoit une progression du chiffre d'affaires hors change comprise entre 6 % et 8 %, dont une croissance en base homogène1 comprise entre 3 % et 5 %. La contribution de l'activité2 devrait, quant à elle, se situer autour de 18,5 % du chiffre d'affaires, un niveau reflétant l'impact dilutif à court terme du rapide développement des activités de vente en ligne. Compte tenu de l'effet graduel des plans d'actions au cours de l'année et de la base de comparaison, le groupe anticipe un niveau de croissance et de rentabilité plus élevé au second semestre qu'au premier semestre. A propos d'Essilor Essilor est le numéro un mondial de l'optique ophtalmique. De la conception à la fabrication, le groupe élabore de larges gammes de verres pour corriger et protéger la vue. Sa mission est d'améliorer la vision pour améliorer la vie. Ainsi, le groupe consacre plus de 200 millions d'euros par an à la recherche et à l'innovation pour proposer des produits toujours plus performants. Ses marques phares sont Varilux®, Crizal®, Transitions®, EyezenTM, Xperio®, Foster Grant®, BolonTM et Costa®. Essilor développe et commercialise également des équipements, des instruments et des services destinés aux professionnels de l'optique. Essilor a réalisé un chiffre d'affaires net consolidé de plus de 7,1 milliards d'euros en 2016 et emploie 64 000 collaborateurs. Le groupe, qui distribue ses produits dans plus d'une centaine de pays, dispose de 33 usines, de 490 laboratoires de prescription et centres de taillage-montage ainsi que de 5 centres de recherche et développement dans le monde. Pour plus d'informations, visitez le site www.essilor.com. L'action Essilor est cotée sur le marché Euronext Paris et fait partie des indices Euro Stoxx 50 et CAC 40.   Codes : ISIN : FR0000121667 ; Reuters : ESSI.PA ; Bloomberg : EI:FP. En 2016, le chiffre d'affaires consolidé du groupe Essilor s'est établi à 7 115 millions d'euros, en progression de 7,6 % hors change. En base homogène1, les ventes ont crû de 3,6 %, dont un premier semestre en croissance de 4,1 % et un second semestre en hausse de 3,1 % par rapport à une base de comparaison plus élevée. L'effet de périmètre (+ 4,0 %) se compose intégralement de la contribution d'acquisitions dites organiques3  au cours de l'année. L'effet de change global (- 1,7 %) reflète une  appréciation de l'euro face aux principales monnaies de facturation du groupe, principalement la livre sterling, le yuan chinois, le real brésilien, le dollar canadien et le peso mexicain, mais qui a été partiellement compensée par le renchérissement, face à l'euro, du yen japonais et du dollar américain en fin d'année. Aux Etats-Unis, la croissance avec les optométristes indépendants s'est essentiellement appuyée sur le déploiement de nouvelles offres pour les membres des plateformes de service - Vision Source, PERC/IVA et Optiport - segment du marché qui affiche la plus forte croissance aux Etats-Unis. Ces solutions visent, notamment, à accélérer le développement des catégories de produits à valeur ajoutée et à optimiser la chaîne d'approvisionnement des magasins membres de ces alliances. L'Europe a réalisé une croissance en base homogène1 de 3,4 %. Les campagnes marketing ont généré dès le début de l'année une dynamique porteuse pour les verres à valeur ajoutée et pour le nouveau verre Eyezen(TM). Cette dynamique s'est traduite, au deuxième semestre, par une croissance plus modeste du fait d'une base de comparaison élevée. Les activités Matériel optique et ventes en ligne ont, pour leur part, contribué très positivement à la croissance de l'année. Par pays, les ventes ont été bien orientées en Europe de l'Est et en Russie. En Italie et en Espagne, l'activité a profité de la dynamique des verres Varilux® et Transitions®. Le lancement du verre Eyezen(TM) a été très bien accueilli en France et en Espagne. Les pays nordiques ont bénéficié de la bonne orientation de l'activité avec les grands comptes et des ventes en ligne. Le Royaume-Uni et les pays d'Europe centrale ont, quant à eux, enregistré des performances plus contrastées. La croissance en base homogène1 de 7,5 % de la région Asie/Océanie/Moyen-Orient/Afrique reflète, d'une part, une hausse à deux chiffres des ventes en volume de plusieurs produits innovants (Transitions®, Eyezen(TM)) et, d'autre part,  les bonnes performances des pays à forte croissance. Parmi eux, l'Inde a réalisé une très belle année, notamment grâce aux verres Varilux® et Transitions® mais elle a été pénalisée par la démonétisation de certains billets de banque au dernier trimestre. L'Asie du Sud-Est et l'Afrique ont confirmé leur forte dynamique. Au Moyen-Orient et en Turquie, les efforts d'adaptation à des conditions de marché volatiles ont conduit à une meilleure croissance au quatrième trimestre. La Corée du Sud a profité du succès de l'offre Perfect UV et de l'activité grands comptes. La Chine a poursuivi sa croissance grâce au dynamisme du milieu de gamme et au lancement réussi d'Eyezen(TM), tandis que l'optimisation de la gamme de produits et des réseaux de distribution continue. Dans les pays développés de la région, l'activité a crû au Japon et a accéléré, trimestre après trimestre, en Australie. En Amérique latine, le chiffre d'affaires a progressé de 8,0 % en base homogène1 en 2016 et reflète une forte dynamique dans tous les pays de la région à l'exception du Brésil. Au Brésil, après une bonne résistance de l'activité au premier semestre, celle-ci a été impactée par la récession économique et le contexte politique difficile dans le pays. Les ventes ont légèrement  reculé au deuxième semestre, conséquence de la diminution sensible de la fréquentation dans les magasins d'optique. Néanmoins, le groupe a su tirer parti de sa stratégie multi-réseau, et notamment de ses offres de milieu de gamme dont les verres Kodak®, pour renforcer ses positions au cours de l'année. Le Mexique a affiché la plus forte croissance de la région, porté par un marché dynamique. En Argentine, les ventes ont été  tirées par la demande de produits à valeur ajoutée - Varilux®, Crizal® et Transitions®. La Colombie a profité du succès des campagnes de marketing consommateur. Enfin, au Chili, au Costa Rica et au Nicaragua, le groupe a accéléré la commercialisation de ses verres haut de gamme, dont Varilux® et Crizal®, en s'appuyant sur ses récents partenariats (Ópticas OPV Ltda au Chili et Grupo Vision au Costa Rica et au Nicaragua). L'activité Instruments commercialise des outils à destination des optométristes et des opticiens et qui est incluse au sein des régions de la division Verres et matériel optique. En 2016, l'activité Instruments (+ 8,0 % de croissance en base homogène1) a poursuivi la dynamique à l'oeuvre en 2015 et a enregistré de bonnes performances en Europe et dans l'ensemble des géographies à forte croissance. Cette performance s'est appuyée sur le déploiement d'innovations dans l'ensemble des segments couverts par cette activité : taillage-montage, optométrie (appareils de réfraction et de diagnostic) et appareils de mesure utilisés dans les points de vente. Le renforcement de l'offre de machines de taillage-montage, avec des succès dans l'entrée de gamme (Delta 2), notamment dans les pays à forte croissance, et le milieu de gamme (Neksia® et Itronics), a apporté au groupe une forte croissance sur le segment de la finition des verres, sa première ligne d'activité. Dans un marché dynamique, l'activité optométrie a, pour sa part, bénéficié de contrats de vente d'appareils de réfraction auprès de certains grands comptes en Europe et de la montée en puissance de son réseau de distribution avec, notamment, l'acquisition d'Axis Medical qui va permettre au groupe d'accélérer la distribution de ses technologies de réfraction au Canada. Enfin, les ventes d'appareils de mesure, dont la tablette M'Eyefit®, ont également été bien orientées. La division Equipements a enregistré une croissance en base homogène1 de 4,7 % alimentée principalement par un net rebond des pays à forte croissance par rapport à l'année précédente. En Amérique latine, l'activité a été soutenue par les commandes de machines de surfaçage numérique par de nombreux laboratoires de petite taille. L'Asie a profité de l'augmentation des capacités de production de plusieurs laboratoires servant aussi bien les marchés domestiques que l'export. En Europe, l'activité ophtalmique a bénéficié de la modernisation par plusieurs grands comptes de leurs machines de traitement et de surfaçage. En Amérique du Nord, l'activité a enregistré une progression plus modeste due à un ralentissement des investissements des chaînes d'optique et des laboratoires en cours d'année. En 2016, la division Sunglasses & Readers a réalisé une croissance en base homogène1 de 1 %. Après un premier semestre fortement impacté par une météo défavorable et le recul des ventes de Xiamen Yarui Optical (Bolon(TM)), la croissance en base homogène a atteint 6,7% au second semestre. En Amérique du Nord, l'activité de lunettes prémontées de FGX International a souffert d'une base de comparaison défavorable, plusieurs contrats avec des grands comptes ayant été renouvelés en 2015. Cependant, les ventes de lunettes loupes aux consommateurs ont été en hausse de près de 4 %. En ce qui concerne l'activité solaire, malgré une météo défavorable qui a impacté les ventes aux consommateurs, les ventes de lunettes de soleil de FGX se sont bien développées grâce à des extensions de gammes de produits chez des clients existants et des gains d'espace chez de nouveaux clients. Costa a affiché, en 2016, la meilleure performance du marché solaire américain. Son rythme de croissance a néanmoins ralenti par rapport à 2015, en raison des difficultés de plusieurs acteurs de la distribution spécialisée dans le sport et des réductions de stocks de certaines chaînes. En Chine, Xiamen Yarui Optical (Bolon(TM)) a réalisé un chiffre d'affaires en légère décroissance, le premier semestre ayant été très perturbé par la mise en place du nouveau système de gestion des stocks. Au second semestre, et surtout au quatrième trimestre, la croissance est repartie à un niveau supérieur à celle du marché solaire en Chine grâce à une collection 2017 très bien accueillie par les détaillants chinois. Au 4ème trimestre, le chiffre d'affaires du groupe a affiché une progression de 7,2 % dont 3 % en base homogène1. Les divisions Sunglasses & Readers (+ 6,5 %) et Equipement (+ 5,2 %) ont réalisé une performance robuste. La division Verres et matériel optique (+ 2,4 %) a subi l'effet négatif d'une base de comparaison élevée par rapport au 4ème trimestre 2015. L'effet périmètre (+ 4,0 %) a reflété principalement l'apport des acquisitions réalisées au premier semestre. L'effet de change légèrement positif (+ 0,2 %) a résulté, pour l'essentiel, de l'appréciation du dollar américain et du réal brésilien face à l'euro, ce qui a compensé l'impact de la dépréciation de la livre sterling. Par région et par division, les faits marquants étaient : (a) L'EBITDA (Earnings Before Interests, Taxes, Depreciation & Amortization) est un indicateur défini comme la contribution de l'activité avant incidence des amortissements et dépréciations des immobilisations corporelles et incorporelles et amortissements des revalorisations de stocks générés par des acquisitions. Investissements Les investissements corporels et incorporels s'élèvent à 294 millions d'euros en 2016. Ils recouvrent  essentiellement les investissements industriels pour soutenir la croissance du groupe. Les investissements financiers représentent 754 millions d'euros et incluent, notamment, les acquisitions réalisées au Royaume-Uni dans le domaine de l'Internet (Vision Direct Group Ltd et MyOptic Group Ltd), ainsi que Photosynthesis Group Co Ltd en Chine dans la division «Sunglasses & Readers». Rapprochement d'Essilor et de Luxottica (extrait du communiqué du 16 janvier 2017) Essilor et Delfin, actionnaire majoritaire du groupe Luxottica, ont annoncé le 16 janvier 2017 avoir signé un accord en vue de créer un acteur intégré et mondial de l'optique par le rapprochement d'Essilor et de Luxottica. Visant à répondre aux besoins croissants de santé visuelle, le nouveau groupe serait en mesure de proposer une offre complète associant un portefeuille important de marques, une capacité de distribution mondiale et une complémentarité d'expertises dans les verres correcteurs, les montures et le solaire. L'opération consisterait en un rapprochement stratégique des activités d'Essilor et de Luxottica selon le schéma suivant : (i) Delfin apporterait la totalité de sa participation dans Luxottica (environ 62 %) à Essilor en échange d'actions nouvelles émises par Essilor dans le cadre d'un apport-scission soumis à l'approbation de l'assemblée générale d'Essilor, sur la base d'une parité d'échange de 0,461 action Essilor pour une action Luxottica et (ii) Essilor lancerait ensuite une offre publique d'échange obligatoire, conformément aux dispositions de la loi italienne visant l'ensemble des actions émises par Luxottica restant en circulation, selon la même parité d'échange, en vue d'un retrait de la cote des actions de Luxottica. Sur la base des comptes 2015 des deux sociétés, le nouvel ensemble représenterait un chiffre d'affaires net supérieur à 15 milliards d'euros, un EBITDA net autour de 3,5 milliards d'euros et plus de 140 000 collaborateurs. La réalisation de l'opération est attendue pour le deuxième semestre 2017, sous réserve de la satisfaction de plusieurs conditions suspensives, dont l'approbation de l'opération par les actionnaires d'Essilor réunis en assemblée générale et par les titulaires de droits de vote double réunis en assemblée spéciale, ainsi que l'obtention des autorisations par les autorités de concurrence concernées. Acquisitions Depuis le 1er janvier, Essilor a poursuivi sa politique de partenariat avec des leaders locaux sur le marché de l'optique, et a conclu 4 transactions représentant un montant de chiffre d'affaires annuel de 19 millions d'euros environ. Au Brésil, le groupe a acquis la majorité du capital de Visolab Produtos Opticos Ltda, un  laboratoire de prescription situé dans l'Etat de Sergipe et réalisant un chiffre d'affaires d'environ 22 millions de réals brésiliens. En Inde, Essilor a fait l'acquisition d'une participation majoritaire dans Mangalsons Optics PTE Ltd, un distributeur de verres organiques et minéraux, de lunettes de soleil et de montures de prescription ayant réalisé un chiffre d'affaires d'environ 460 millions de roupies indiennes en 2016. Le groupe s'apprête à faire son entrée en Ethiopie en signant un accord pour prendre une participation majoritaire dans le capital de Sun Optical Technologies, un laboratoire de prescription réalisant un chiffre d'affaires d'un peu plus d'un million d'euros. La finalisation de cette transaction est soumise à l'approbation finale des autorités locales. Aux Pays-Bas, le groupe a acquis une participation majoritaire dans Optitrade Logistics Center (OLC), la plateforme de distribution d'Optitrade, un groupement d'achat qui regroupe environ 650 magasins d'optique dans le pays. Ce partenariat vise à développer de nouvelles offres de produits et de services et à accompagner la croissance des membres d'Optitrade sur le marché domestique. OLC continuera d'être dirigée par l'équipe actuelle.


BOSTON & LONDRES--(BUSINESS WIRE)--Les investisseurs institutionnels déclarent que les événements politiques et économiques pourraient décupler la volatilité des marchés en 2017, selon une étude de Natixis Global Asset Management. Par conséquent, ils prévoient de réorganiser leurs portefeuilles, de se fier à la gestion active et aux actifs alternatifs pour gérer les risques et augmenter les rendements. « Des forces politiques et économiques sans précédent aux quatre coins du monde représentent la principale préoccupation des entreprises en 2017 », souligne John Hailer, président-directeur général de Natixis Global Asset Management pour les Amériques et l’Asie, et chef de la distribution mondiale. « Sur des marchés volatiles, les entreprises se tournent vers la gestion active pour consolider les rendements et pour gérer les risques. » À plus long terme, les institutions prévoient avoir moins recours aux placements passifs que ce qu’elles anticipaient. Elles affirment que 67 % de leurs actifs sont sous gestion active et que le reste (33 %) est placé dans des véhicules qui évoluent au rythme de leur indice, et qu’elles prévoient que la part de placements passifs augmentera d’un seul point de pourcentage, pour atteindre 34 % au cours des trois prochaines années. Dans un sondage de 2015 par Natixis, les investisseurs prévoyaient que 43 % des actifs seraient sous gestion passive d’ici 3 ans. La moitié (50 %) des décideurs institutionnels internationaux sondés prévoient avoir davantage recours aux stratégies alternatives pour 2017. Deux tiers (67 %) s'en servent à des fins de diversification, et les autres (31 %) à des fins d’atténuation des risques. Les titres de marchés émergents, les titres à revenu fixe et à rendement élevé et les titres financiers sont aussi du lot des gagnants. L’aperçu pour les marchés américains et émergents a également été fortement affecté par l’élection. Quarante-trois pour cent (43 %) des investisseurs interrogés avant l’élection affirment que les marchés émergents connaîtront le meilleur rendement en 2017, contre 31 % après l’élection. Pendant ce temps, 46 % des personnes interrogées avant l’élection affirment que les États-Unis constitueraient la pire déception parmi les bourses mondiales, contre 31 % après. Soixante-trois pour cent (63 %) des investisseurs affirmaient que les obligations à plus long terme du gouvernement constitueraient la catégorie d’actifs à revenu fixe la plus décevante en 2017, contre 76 % après. Natixis a interrogé 500 investisseurs institutionnels à propos de leur opinion sur le risque, les prédictions de distribution des actifs et leur opinion sur le rendement des marchés. Les répondants sont des gestionnaires de fonds de retraite privés et publics, des fondations, des fonds d’assurance et des fonds de richesse souveraine en Amérique du Nord, en Amérique latine, au Royaume-Uni, en Europe métropolitaine, en Asie et au Moyen-Orient. Les données ont été recueillies en octobre et en novembre 2016 par la société de recherche CoreData. Les conclusions sont publiées dans un nouveau document technique, « Buckle up, it’s going to be a bumpy ride » (anglais). Pour de plus amples renseignements, consultez le http://durableportfolios.com/Institutional-Survey-Outlook-2016 Natixis Global Asset Management propose aux professionnels en placements réfléchis du monde entier des idées nouvelles afin de leur permettre de mieux comprendre et gérer les risques. Grâce à notre approche Durable Portfolio ConstructionMD, nous les aidons à développer des portefeuilles plus stratégiques qui les aident à relever les défis des marchés imprévisibles d’aujourd’hui. Nous puisons dans les connaissances du secteur et des investisseurs, et nous formons des partenariats étroits avec nos clients afin d’appuyer la discussion avec des données objectives. Avec un siège social à Paris et à Boston, les actifs gérés de Natixis Global Asset Management, S.A. totalisaient 897 milliards de dollars au 30 septembre 2016.2Natixis Global Asset Management, S.A. fait partie de Natixis. Cotée à la bourse de Paris, Natixis est une filiale de la BPCE, le deuxième plus grand groupe bancaire en France. Les sociétés de gestion d’investissements et groupes de distribution et de service de Natixis Global Asset Management, S.A. incluent Active Investment Advisors; 3 AEW Capital Management; AEW Europe; AlphaSimplex Group; Axeltis; Darius Capital Partners; DNCA Investments; 4 Dorval Finance; 5 Emerise; 6 Gateway Investment Advisers; H2O Asset Management; 5 Harris Associates; IDFC Asset Management Company; Loomis, Sayles & Company; Managed Portfolio Advisors;3 McDonnell Investment Management; Mirova; 7 Natixis Asset Management; Ossiam; Seeyond; 7 Vaughan Nelson Investment Management; Vega Investment Managers; et Natixis Global Asset Management Private Equity, qui inclut Seventure Partners, Naxicap Partners, Alliance Entreprendre, Euro Private Equity, Caspian Private Equity et Eagle Asia Partners. Visitez ngam.natixis.com pour plus de renseignements. Tout investissement comprend des risques, y compris de perte. Il n’y a aucune garantie que la gestion active améliorera les rendements et les gestionnaires actifs sous-performent souvent par rapport à leur indice de référence. Les placements alternatifs présentent des risques particuliers qui peuvent être différents de ceux qui sont associés aux placements traditionnels, y compris l’illiquidité et la possibilité de plus grandes pertes ou gains. Les investisseurs doivent avoir pleinement conscience des risques associés à tout placement avant de l'opérer. 1 Mise à jour quantitative Cerulli: Global Markets 2016 a classé Natixis Global Asset Management, S.A. comme le 16ème plus important gestionnaire d’actifs dans le monde selon les actifs gérés (870,3 milliards de dollars) au 31 décembre 2015. 2 Valeur nette des actifs au 30 septembre 2016. Les actifs sous gestion (ASG) peuvent inclure des actifs pour lesquels des services d’ASG non réglementaires sont fournis. Les ASG non réglementaires comprennent des actifs qui ne tombent pas à l’intérieur de la définition d’« ASG réglementaire » de la SEC dans le formulaire ADV, partie 1. 3 Une division de NGAM Advisors, L.P. 4 Une marque de DNCA Finance. 5 Une filiale de Natixis Asset Management. 6 Une marque de Natixis Asset Management et Natixis Asset Management Asia Limited, situées à Singapour et à Paris. 7 Exploitée aux États-Unis par Natixis Asset Management U.S., LLC.


News Article | February 2, 2016
Site: news.yahoo.com

Bird's-eye view of one of the hourly eruptions at Santiaguito in Guatemala. More Jeffrey Johnson, associate professor of geosciences at Boise State University, contributed this article to Live Science's Expert Voices: Op-Ed & Insights. The next time you're served a flat Coke, impress your friends with volcano jargon. Complain to the waiter that your beverage is "depleted of volatiles." Then, suggest that if the cola were to be heated, its solubility might drop, catalyzing bubble growth, which would result in improved taste and/or a "paroxysmal eruption." If they're still listening, tell them that this is what occurs in volcanoes. A new article published in the journal Nature recently demonstrated the "critical influence of heat variations in rising magmas" — meaning previously unappreciated temperature changes appear to control the occurrence, and explosivity, of eruptions. Volcanoes erupt explosively when gas-charged magma reaches Earth's surface. Volcanologists refer to magmatic gases as volatiles because the amount of those gases within the rising magma determines whether a volcano explodes (in a volatile fashion) or effuses lazily. The formation and growth of gas bubbles are complex processes that fascinate nearly every volcanologist. There are volcanologists who peer inside tiny crystals to measure minuscule amounts of dissolved gas, and there are volcanologists who use spectroscopy — specifically studies of how minerals absorb ultraviolet light — to measure the copious gases billowing from a vent. Experimental volcanologists melt volcano rocks and infuse them with gases. And there are numerical modeling volcanologists, who might never venture into the field but develop sophisticated code to simulate degassing and eruptions. [50 Amazing Volcano Facts ] But they all consider what happens to a parcel of magma as it rises toward, and breaks apart at, a volcano's vent. Magma deep within a volcano starts its ascent slowly, but eventually, it accelerates toward the Earth's surface. This happens because as magma rises it escapes from crushing overpressure and bubbles grow. The magma's environment changes dramatically, and so does the character of the molten rock, including — most vitally — the amount of volcanic gas that fuels explosivity. Let's imagine magma's journey starting about 2 miles, or roughly 3 kilometers, below a volcanic vent. This is approximately the depth of a large volcano's base, and the pressures there are intense: Magma at this depth is subjected to nearly a thousand times the pressure that exists in the atmosphere. As a result, the magma travels through long fractures or sheetlike "dikes," rather than pipelike conduits that prevail near the surface. As the magma flows, the surrounding colder rock is cracked apart several inches, or maybe a couple of feet, allowing the magma to pass through. At such depths, the magma is an extremely viscous fluid, often (but not always) swimming with crystals, but largely it is devoid of bubbles. The absence of bubbles doesn't mean there is no gas, but that it is mostly tied up, or dissolved, within the magma. At least 1 percent (and potentially as much as 5 percent) of the mass of magma at this depth will be invisible, locked-in gas. While these gas amounts may not seem too significant, think of, for example, if magma were to fill 1 percent of the mass of a small hot tub's contents. It would contain more than 50 lbs. (roughly 20 kilograms) of gas, which, if expanded catastrophically — as is typical during volcanic eruptions — equates to the energy released by about 50 lbs. of exploding TNT, or about 100 megajoules of energy. Magma, even when devoid of bubbles, ascends because of buoyancy. Because it is somewhat less dense than the colder rock surrounding it, it kind of floats its way upward. At first, it may rise sluggishly, but as the magma reaches shallower levels, it can accelerate. Significant changes occur in the melt as the confining pressure diminishes. More bubbles start to appear, and they serve to diminish the overall density of the fluid. As these bubbles expand, the density decreases further. Buoyancy then increases, facilitating a quicker ascent, enhanced bubble creation and expansion. This feedback causes the density to drop and the buoyancy to increase. This cycle continues until the magma is ripped apart. Those once-invisible bubbles rend the surrounding magma to shreds, and gas, ash and any piece of the volcano in the way is blown out of the crater. Such pressure-controlled degassing has been the standard scientific model for explosive eruptions. But now, Yan Lavallée, Professor within the School of Environmental Sciences at the University of Liverpool in England, has introduced a major tweak to that model. In a new paper in the journal Nature entitled "Thermal vesiculation during volcanic eruptions." Lavallée has demonstrated that while decompressing magma is prone to degas, it further degasses when it heats up. And it probably heats up and degasses a lot more than scientists have thought. Scientists agree that, for magma to exist in melted form, rather than as a solid rock, it must be hot. On average, magma is approximately 2,000 degrees Fahrenheit, or around 1,000 degrees Celsius.  Less commonly recognized, however, is that magma can get quite a bit hotter via two processes that exist in most volcano conduits.  Firstly, magma gives off heat when portions of it start to freeze. Just like in water, the freezing produces crystals, and as the crystals form, they give off heat. A cubic centimeter (about 0.06 cubic inches) of "freezing" crystals, like quartz, will heat a kilogram (about 2.2. lbs.) of surrounding magma by 5 degrees C (9 degrees F). That added heat can induce gas to come out of the fluid magma. Secondly, magma will heat up as it flows through constricted conduits. As viscous fluids are forced through cracks or narrow pipes, the flowing rock releases heat due to friction. Supersticky magma flowing into a crack is sort of like taffy being squeezed through the small-bore needle of a syringe. The taffy would also heat up and become more runny.  Lavallée, who was the lead researcher on the study, and his colleagues, suggest significant heating causes those processes, merging geologists' pre-existing understanding of geophysical constraints with analyses of rock samples and laboratory simulations of the processes. Back in 2013, Lavallée scaled the dome of Santiaguito, an active volcano in Guatemala, to search for rocks that bear testament to frictional heating.  The dome's gray surface is a jumbled collection of house-size rock spines, extruded over the last decades, and is — in some places — still extruding. Immense blocks have been squeezed toward the surface as an incredibly sticky, viscous magma. In the process, these rocks broke and cracked before later annealing from continued exposure to the intense heat (around 1000 degrees C) inside the volcano.  Lavallée searched the dome lavas for these healed cracks, which he hypothesized would represent fossil passageways of escaping gas. When he returned to his laboratory, he found his evidence: Under an electron microscope, the textures of these annealed cracks revealed ash shards frozen in place following their transport by currents of hot gas originating on the cracks' margins. Spectacular laboratory experiments also supported the theory. Lavallée and his colleagues took fist-size rock samples of lava and pushed them together with tremendous force, then rotated one rock sample slowly against another. This generated intense friction and heat   — enough to melt rock and release copious, previously locked-in gas. The last piece of the puzzle ties the whole story together: Lavallée's geophysicist partners studied a nearby portion of Santiaguito's dome, located a quarter mile (about 0.4 km) away from where the samples were collected. This dome was actively erupting when the team visited, and approximately once per hour, the dome surface and its interior would lurch upward, forcing the viscous rock to flow and internally deform.  Viewed from a safe vantage point, the periodic activity was spectacular. Within seconds of an eruption's onset, columns of ash and gas plumes rise to hundreds of meters and eventually reach more than a kilometer high. Incandescent blocks the size of microwave ovens are blown skyward and then crash onto the volcano's flanks, breaking open and cascading downward. The geophysicists captured the associated, subtle, underground movements at Santiaguito using an array of instruments, including seismometers (which measure movements in the ground) and tiltmeters (which measure the tilting of the Earth's surface). These sensors reveal the depth and magnitude of rock movement — data the researchers used to estimate the amount of gas that accumulates during eruptive cycles.  According to Lavallée's theory, his rock and magma movements can induce temperature gains of hundreds of degrees, promoting volatilization of the previously "flat" magma and subsequent violent degassing. The dome rocks and eruptions at Santiaguito serve as tantalizing evidence of how frictional heating can lead to volcanic explosions. In most ways, Santiaguito lava and flat cola are horrible analogues. Nonetheless, Santiaguito's behavior offers insight toward understanding vital processes that influence volcanic explosivity at other analogous volcanoes — findings at the Santiaguito volcano laboratory are revealing the dynamics of hazardous, dome volcanoes across the globe. Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook, Twitter and Google+. The views expressed are those of the author and do not necessarily reflect the views of the publisher. This version of the article was originally published on Live Science . Copyright 2016 LiveScience, a Purch company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.


News Article | November 2, 2016
Site: phys.org

Psyche is thought to be the largest metallic asteroid in the solar system, at 300 km (186 miles) across and likely consists of almost pure nickel-iron metal. Scientists had thought Psyche was made up of the leftover core of a protoplanet that was mostly destroyed by impacts billions of years ago, but they may now be rethinking that. "The detection of a 3 micron hydration absorption band on Psyche suggests that this asteroid may not be metallic core, or it could be a metallic core that has been impacted by carbonaceous material over the past 4.5 Gyr," the team said in their paper. While previous observations of Psyche had shown no evidence for water on its surface, new observations with the NASA Infrared Telescope Facility found evidence for volatiles such as water or hydroxyl on the asteroid's surface. Hydroxyl is a free radical consisting of one hydrogen atom bound to one oxygen atom. "We did not expect a metallic asteroid like Psyche to be covered by water and/or hydroxyl," said Vishnu Reddy, from the University of Arizona's Lunar and Planetary Laboratory, a co-author of the new paper about Psyche. "Metal-rich asteroids like Psyche are thought to have formed under dry conditions without the presence of water or hydroxyl, so we were puzzled by our observations at first." Asteroids usually fall into two categories: those rich in silicates, and those rich in carbon and volatiles. Metallic asteroids like Psyche are extremely rare, making it a laboratory to study how planets formed. For now, the source of the water on Psyche remains a mystery. But Redddy and his colleagues propose a few different explanations. One is, again, Psyche may not be as metallic as previously thought. Another option is that the water or hydroxyl could be the product of solar wind interacting with silicate minerals on Psyche's surface, such as what is occurring on the Moon. The most likely explanation, however is that the water seen on Psyche might have been delivered by carbonaceous asteroids that impacted Psyche in the distant past, as is thought to have occurred on early Earth. "Our discovery of carbon and water on an asteroid that isn't supposed to have those compounds supports the notion that these building blocks of life could have been delivered to our Earth early in the history of our solar system," said Reddy. If we're lucky, we won't have to wait too long to find out more about Psyche. A mission to Psyche is on the short list of mission proposals being considered by NASA, with a potential launch as early as 2020. Reddy and team said an orbiting spacecraft could explore this unique asteroid and determine if whether there is water or hydroxyl on the surface. More information: Detection of Water and/or Hydroxyl on Asteroid (16) Psyche. arxiv.org/abs/1610.00802


News Article | November 15, 2016
Site: www.sciencemag.org

Between the jungle and the rice paddies, Fidel Costa struggled to find bare rock on the slopes of Mount Gede, a towering volcano near the western tip of the Indonesian island of Java. But an abandoned quarry hewn into the mountainside offered a rare chance to nab a few samples. So on a muggy day in 2011, Costa, a volcanologist at the Earth Observatory of Singapore, scrambled up the steep wall to some rocks, marbled like rye bread, which he pried loose with a hammer. Four thousand years ago, they erupted from Gede and fell out of a cloud of hot ash. There are no accounts of that eruption, let alone records of any seismic tremors or burps of gas leading up to it—the clues scientists now use to infer what's brewing deep beneath a volcano. Indeed, the volcano's last outburst occurred in 1957, long before modern monitoring efforts began, so scientists know little about its temperament. What signs portend Gede's eruptions, and how much warning do they give? For the millions of people living on its flanks, as well as in the nearby cities of Jakarta and Bandung, the answers are critical. There's no indication that Gede will erupt anytime soon. But when it does, Costa says, "anything that happens there is going to be a big mess." From the rocks released by that 4000-year-old eruption, however, Costa and his colleagues at the Center for Volcanology and Geological Hazard Mitigation of Indonesia in Bandung were able to glean some crucial clues about Gede's behavior. The clues were locked in crystals, most smaller than lentils, embedded in the rocks. Each crystal grew in a soup of magma deep underground, accreting layers that bore witness to the events that preceded the eruption, and—most importantly—how fast they unfolded. These crystal clocks told Costa's team that Gede's 4000-year-old eruption came roughly 4 weeks after the injection of a fresh batch of magma beneath the volcano. Crystals from four more ancient eruptions gave similar answers. The pattern gives planners an idea of what to expect in the future: When sensors detect signs of magma stirring below the slumbering giant, an eruption may follow within weeks. "It might be uncertain, but it's much better than not knowing anything," Costa says. Costa has spent years learning to coax such stories out of tiny volcanic crystals with a technique he helped develop, known as diffusion chronometry. And it's catching on. "It's one of those techniques that is about to explode in popularity," says Tom Sisson, a volcanologist at the U.S. Geological Survey in Menlo Park, California. Already, the few researchers adept at using the technique have found that magma can tear through the crust at searing velocities, and that volcanoes can gurgle to life in a geologic instant. Instead of taking centuries or millennia, these processes can unfold in a matter of decades or years, sometimes even months, says Kari Cooper, a volcano geochemist at the University of California, Davis. The results help explain why geophysicists haven't found simmering magma chambers under volcanoes like Yellowstone, and why some eruptions are more violent than others. "This is something that has the potential to really be a game changer in a lot of ways," she says. Back in his lab in Singapore, Costa gleans his volcano histories from cellophane-thin slices of rock. Backlit under a microscope, minerals in the slices—including plagioclase, olivine, and pyroxene—burst into focus: polygonal islands swimming in a dark sea of rock. Many have concentric bands like tree rings, which formed as the crystals grew in an ever-changing bath of liquid magma. The chemistry of each new band records the evolving composition of the magma, or changes in its temperature or pressure. Costa uses an instrument called an electron microprobe to map the chemical variations along the crystal faces, making a measurement every few microns. In the Gede crystals, the microprobe revealed higher concentrations of magnesium and iron in the outermost layers, which suggested that a fresh burst of magma rich in these elements bubbled up beneath Gede shortly before the eruption—potentially triggering it. But how shortly? That's where Costa and Daniel Krimler, a graduate student at the observatory, turned to diffusion chronometry, which converts the chemical smudging between the rim and the crystal's core into an estimate of time. Researchers first developed the technique, originally dubbed geospeedometry, in the 1960s. They used it to estimate cooling rates in meteorites and rocks that have been subjected to extreme heat and pressure. The method relies on the premise that nature rarely abides sharp gradients. Just as a few drops of food coloring will diffuse throughout a glass of water—no stirring required—so, too, will diffusion shuffle atoms from areas of high concentration to low concentration within a solid crystal lattice. In the Gede crystals, diffusion moved atoms of magnesium and iron from the crystal rims to the cores, and shuttled other elements in the opposite direction to fill the vacancies left by these atoms. It transformed an abrupt, steplike change in chemical composition into a more gradual curve. By knowing how fast magnesium and iron diffuse through specific minerals, Costa and Krimler could calculate how long diffusion went on after the magma injection and before the volcano erupted, freezing the chemical profile in place. They had a stopwatch. It's not quite that simple, of course. Diffusion rates depend not only on the element and mineral in question, but on the temperature, pressure, and oxidation state the crystal experienced, which researchers estimate from other clues in the crystals. In the 1980s, pioneers like Sumit Chakraborty, a geologist at Ruhr University in Bochum, Germany, began the tedious work of pinning down these diffusion parameters across a range of conditions. That meant long hours in the lab torturing natural and synthetic crystals with heat and pressure and then watching diffusion proceed. At first, single experiments could take weeks, but the results gave diffusion chronometry teeth. Curiously though, the technique didn't catch on with volcanologists until the turn of the century. By the time Costa published his first paper on the topic in 2003, applying diffusion techniques to volcanic crystals from the San Pedro volcano in Chile, several other researchers were having similar epiphanies. It was an idea whose time had come. One appeal of diffusion chronometry lies in its ability to track a wide range of volcanic processes. Any time a new zone forms within a crystal, diffusion chronometry can theoretically exploit it. And that allows scientists to target many stages leading up to an eruption, including when magma rises from the mantle, when it collects in crustal reservoirs and mixes with other magmas, and when it barrels up through the plumbing of the volcano toward the surface. Take the initial ascent of magma from the mantle. Terry Plank, a geochemist at Columbia University's Lamont-Doherty Earth Observatory in Palisades, New York, and a former postdoctoral researcher in her lab, Philipp Ruprecht, wanted to understand the origin of magma in a famous eruption of the Irazù volcano in Costa Rica that lasted from 1963 to 1965. In certain olivine crystals, the researchers noted variations in nickel concentrations inside the crystal cores that appeared to have formed in the mantle. The fact that the chemical variations survived the ascent through the crust implied that diffusion had little time to smear them out. Plank and Ruprecht concluded that the magma must have risen through roughly 35 kilometers of crust in just months, or at most, a few years. "That was a surprise," Plank says. The results—suggesting the possibility of a direct connection between the mantle and the surface—contradicted the widespread idea that magma follows a tortuous path upward, pooling in magma chambers along the way before finally erupting. In many cases, though, it appears that magma does spend millennia loitering a few kilometers beneath the surface, only to mobilize rapidly before an eruption. At Mount Hood in Oregon, for example, Cooper examined rocks from the volcano's last two eruptions, 1500 and 220 years ago. She focused on plagioclase crystals that formed in shallow magma chambers in the crust. By measuring the concentrations of uranium and its radioactive daughter elements, she found that these crystals were born at least 20,000 years ago. Many of these plagioclase crystals also had numerous layers with different chemical compositions, which they acquired over their long lifetimes. When Cooper looked closely at the boundaries between these layers, she found something startling: They were only slightly smudged, suggesting that in spite of their age, the crystals had only a brief sojourn in hot, liquid magma. In 2014, she and Adam Kent of Oregon State University in Corvallis explained their discovery by proposing that the magma spent as much as 99% of its time in storage at temperatures too cool to erupt and too cool for diffusion. Instead, it existed in a mostly solid crystalline mush beneath Mount Hood. The results support the so-called "mush model," which has gained traction in the last decade or so. Cooper's work suggests that magma may liquefy and erupt even more quickly than many researchers thought. "It's a bit of a subtle shift, but it's very important, because all of a sudden, everything you want to do"—mixing and assembling the final pot of magma that erupts—"all that has to happen really quickly," Cooper says. Crystal clocks from a 3600-year-old eruption of the Greek volcano Santorini, which had been dormant for 18,000 years, suggest that it awakened in a century or less. If other volcanoes behave similarly, it would explain why researchers have struggled to find evidence for large molten magma chambers on Earth today—such vats of liquid magma may only exist immediately prior to an eruption. When an eruption finally happens, magma races from its subterranean source to the surface. Plank's current quest is to understand whether the speed of that ascent influences how explosively a volcano erupts—causing Hawaii's Kilauea, for example, to erupt gently today in spite of explosive outbursts in the past. Plank and others suspect that, all else being equal, a slowly rising magma has more time to lose dissolved gases—and therefore erupts less violently—than magma that gushes toward the surface. "It's not the gas in the seltzer bottle, it's how fast you open the seltzer bottle," she says. But how does one measure the speed of magma rising deep beneath the ground? Instead of studying diffusion in crystals, Plank has looked at how dissolved volatiles like water and carbon dioxide diffuse through melt tubes, tiny burrows in crystals that fill with liquid magma. As crystals rise toward the surface, the volatiles trapped in a melt tube diffuse toward its mouth, striving to stay in equilibrium with the dropping concentrations in the magma outside the crystal. This produces a diffusion profile along the tube that Plank and others can use as a clock. Because these gases move relatively fast, the technique allows them to time processes that unfold rapidly. They have found that slugs of magma can rise 10 kilometers in roughly 10 minutes. "It's like a freight train," she says. Her preliminary results from a handful of volcanoes in Alaska, Hawaii, and Central America support the idea that ascent rates correlate with explosivity. She's working now to study more volcanoes, but, she says, "the problem is that most of those eruptions go unsampled." So she's getting creative; when the Pavlof Volcano erupted violently on the Alaska Peninsula in March of this year, she bartered a box of fresh fruit for a trashcan of ash collected by locals. Her team still had to search through it for crystals that meet their criteria—another challenge. "My students pick for hours under a microscope looking for the one olivine that has a weird tube in it," she says. "We published a paper on four of them, that's how rare they are." Relying on a handful of tiny crystals to track an entire body of magma worries some outsiders. "People are making strong interpretations based on not a whole lot of results," Sisson says. Dan Morgan, a petrologist at the University of Leeds in the United Kingdom and an early practitioner of diffusion chronometry, shares that concern. Although there's no way around it in Plank's work, Morgan says researchers should be careful with small sample numbers. "If you find five very photogenic crystals, they will be anomalous," he says. One 2015 study, led by Thomas Shea, a volcanologist at the University of Hawaii in Honolulu, points out that researchers must analyze at least 20 olivine profiles to account for the fact that chemicals diffuse in three dimensions through a crystal. So Morgan and others have been working on faster ways to measure and analyze diffusion profiles. One strategy is to skip the slow process of moving point by point across the crystal face with the microprobe, and instead use a technique called backscattered electron microscopy, which essentially snaps a chemical photo of the crystal. The brightness of the image can serve as a proxy for the concentration of iron and magnesium, and the process takes much less time. Both Morgan and Costa are also developing user-friendly software to help researchers who aren't experts in diffusion modeling interpret their data. Morgan says that when he started out, he could model two or three chemical profiles in a day; his new daily record is 80. By speeding up the process, he hopes researchers can generate more data, "which then starts to tell you things at the scale of the whole magma mass rather than an individual crystal's story." Others worry about uncertainties in the diffusion rates, especially for less common elements and minerals. But Costa says that it's important to keep perspective. Even if the uncertainties are 100% or more, the clock results can still be meaningful. "If I find 1 month, 100% uncertainty is a few months," he says. "It's still not 100 years." The biggest challenge, according to experts like Costa and Morgan, isn't calibrating the stopwatch—it's knowing which volcanic processes the crystals are recording. That's why many researchers are studying crystals from eruptions of actively monitored volcanoes. Maren Kahl, a petrologist at the University of Iceland in Reykjavik, has used that approach at one of the best studied volcanoes on Earth, Mount Etna in Italy. She and her colleagues examined crystals from eight well-documented eruptive episodes between 1991 and 2008. The researchers were able to tie monitoring records of earthquakes, ground deformation, and gas emissions to pulses of magma recorded in crystal chemistry, which they dated using diffusion chronometry. The result was an unprecedented picture of the volcano's multichambered plumbing, with five different magma zones and three dominant pathways between them. The researchers were even able to create a model of how the volcano erupts based on realistic physics. "We've never been able to quite do that before," Plank says. As researchers get better at linking the crystals' stories with observations of modern eruptions, Kahl says, they will gain confidence about applying the technique to ancient ones, as Costa is doing at Gede. Of the 1500 potentially active volcanoes on Earth, only a small fraction are actively monitored, and fewer still have erupted since scientists started watching. With diffusion chronometry, however, researchers can use crystals to learn the histories and personalities of these hibernating volcanoes. "We can go pick up the rocks, study the minerals, and basically get timescale information about an eruption that happened, let's say, 100,000 years ago," Kahl says. And by diving deep into a volcano's past, scientists can gain a glimpse into its future.


News Article | February 8, 2017
Site: www.csmonitor.com

This is a frame of the 'Trinity' fireball, .025 seconds after detonation. —How did the moon form? Scientists base their models largely on data from moon rocks and meteorites. But those just provide momentary snapshots, not geological processes in action. To test their models, scientists need to figure out just how, and under what conditions, those rocks may have formed. And one team may have just found a new way of thinking about lunar formation. Moon-building happens on a massive scale, so "we were looking for an analogue that was large-scale enough ... to replicate what we thought was going on during the early process of planet formation," James Day, a geochemist at the University of California San Diego, explains in a phone interview with The Christian Science Monitor. Fortunately for Dr. Day and his colleagues, a real-life massive, super hot explosion took place just a few decades ago: the detonation of a nuclear bomb. And it, too, altered the chemistry of rocks. When the dust settled after a plutonium bomb was tested for the first time near Alamogordo, N.M., in July 1945, some of the red soil had become a light green glass. The glass was dubbed trinitite after the test site, called Trinity. "We can use the Trinity glasses – that came from this very profound experiment that's had a huge effect on human history – to scientific benefit," Day says. By studying the trinitite, Day hoped to glean insight into how the material that formed the moon might have changed during, if it formed according to the canonical model of lunar formation. In that classic "great impact" model, a Mars-sized object slammed into the early Earth, vaporizing some material and blasting other rocks from Earth's surface into a disk in Earth's orbit that then accreted to form the moon. What does that have to do with a nuclear bomb test? The impact from the Mars-sized body was probably violent enough to deplete some of the volatile elements in the material that eventually formed the moon, explains Day. Similarly, he thought, the nuclear explosion might have made the trinitite depleted in volatiles. The researchers focused in on the volatile element zinc. The idea was that the hot, high-pressure conditions of the nuclear explosion would mimic the conditions thought to occur in the great impact model and cause evaporative fractionation. In other words, the lighter isotope of zinc would have been more likely to evaporate in the explosion than the heavier isotope. Similar fractionation of zinc has been identified in some moon rocks, called mare basalts. "Our expectation was that when we measured these trinitites, these glasses that formed in the nuclear detonation, that we were either going to see nothing … that in fact, our hypothesis that there was volatile loss during this event was wrong," Day says, "or that we would approach the theoretical values that have been calculated" for the giant impact model, which suggested more loss than the moon rocks displayed. But, he says, it was "startling" how close the zinc composition of the glasses looked to the lunar rocks. Day and his colleagues report their findings in a paper published Wednesday in the journal Science Advances. Does this really tell us anything about the moon? James Van Orman, a geochemist at Case Western Reserve University who was not part of Day's team studying the trinitite, says it's a "creative and unique" idea to use the products of a nuclear test to better understand how such conditions alter a rock's chemical make-up. "There is no question that this constraint on Zn isotopic fractionation during evaporation will be valuable in modeling volatile loss from the Moon, and comparing the models to data from lunar samples," Dr. Van Orman writes in an email to the Monitor. But to draw conclusions about the moon's formation from this one study may be a bit of a leap, he says. Day agrees that his research can't really say much about the mechanism of how the moon may have formed. "All it tells us is that the conditions that we would expect, of high temperatures, very Hadean-like conditions," he says, "were occurring at the time that the moon formed." But Van Orman says it might not even address the event that formed the moon. "This study shows clearly that evaporative loss of Zn can explain the heavy zinc isotopic composition of the mare basalts," he explains. But that doesn't mean it's the only way to explain that composition. The mare basalts are volcanic rocks that cooled from lavas that may had time to degas before they hardened, he says. "I'm not convinced that the evaporative fractionation was associated with lunar formation, rather than later magmatic degassing," Van Orman says. "You don't have to do it during the giant impact," agrees David Stevenson, a planetary scientist at the California Institute of Technology who also was not involved in the study. "There is a big difference between identifying the results of a process and directly applying the specifics of what happened in the Trinity test with what happens in planet formation," Dr. Stevenson writes in an email to the Monitor. "So I doubt that science by analogy (which is what they're doing) is very useful, but I seen value in their work nonetheless." This new study, he says, "quantifies a process that happens when you severely heat a rock (more precisely a droplet of magma). That's useful." Jay Melosh, a geophysicist at Purdue University, suggests that older crustal moon rocks, perhaps from the lunar highlands, may have been a better choice than the mare basalts to compare with the trinitite. Applying this study to questions about the moon's formation may actually complicate the picture, Dr. Melosh says. Scientists thought they had it all figured out decades ago, he explains in a phone interview with the Monitor. But when researchers got better at measuring isotopic differences, they realized the canonical model had a big problem. Melosh refers to this puzzle as "the isotopic conundrum." In the classic model, researchers would expect to see these isotopic fractionations across other volatile elements in moon rocks, like potassium. "In fact," he says, "we don't." [Editor's note: Following the publication of this article, Day pointed out that a paper published in Nature in October 2016 has found evidence of fractionation  of potassium isotopes in lunar rock.] Since this isotopic puzzle has arisen, many scientists have tried to tweak the giant impact model to resolve it. Some have proposed that the impact was particularly violent, while others have thought more "out-of-the-box" and suggested that the moon may actually be made up of many mini-moons. The fact that zinc is isotopically fractionated in the moon rocks but potassium is not "adds to the many mysteries about the moon," Melosh says. "The moon certainly is giving us a lot of puzzles."


News Article | February 15, 2017
Site: www.newscientist.com

We can’t recreate the giant impact that led to the moon’s formation in a lab, but humans have made some other big explosions. By examining residue from the first detonation of a nuclear weapon, researchers have cracked a window into the moon’s past. On 16 July 1945, the US army detonated a nuclear weapon for the first time in an operation codenamed Trinity (see photo, above). As the bomb exploded with an energy equivalent to 20 kilotonnes of TNT, the sand underneath it melted, producing a thin sheet of mostly green glass dubbed trinitite. The explosion brought the area around the bomb to temperatures over 8000°C and pressures nearing 80,000 atmospheres. These extreme conditions are similar to those created as the moon formed in a colossal collision between Earth and another rock, probably about the size of Mars. “It is as close as we can probably get to conditions that you might envisage on a planetary body in the early solar system,” says James Day at the Scripps Institution of Oceanography in California. Fortunately for planetary science, scientists meticulously measured and recorded the details of the Trinity detonation, so there is plenty of information to work with. Day and his colleagues took advantage of that past precision to investigate why the moon has surprisingly little water and other volatiles with a relatively low boiling point – much less than Earth. To do so, they studied the distribution of one volatile element, zinc, in trinitite collected at different distances out from the explosion’s centre. They found that the closer to the explosion the trinitite formed, the less zinc it had, especially when it came to zinc’s lighter isotopes. That’s because these evaporated in the intense heat of the explosion, while the heavier isotopes didn’t and so remained in the trinitite. The ratios of different forms of zinc left behind in trinitite showed remarkable parallels to what was observed in the moon rocks retrieved in the Apollo missions. “What’s critical here is that the fractionation factors – how the heavy and light isotopes separate from each other – exactly match,” says Day. This means that zinc and other volatile elements, most notably water, probably evaporated off the moon while it was being formed in a violent collision or soon afterward, while its surface was still incredibly hot. Previously, glass deposits from the moon with unusually high amounts of volatiles had led scientists to suspect that the moon’s interior might have lots of water, similar to Earth’s mantle. This study casts doubt on that idea; if water evaporated along with other volatiles as the moon was being formed, it’s hard to imagine how much more could have lingered under the surface. “I think it’s a pretty neat use of some of the data that we have on the ground here on Earth to address a planetary problem,” says Patrick McGovern at the Lunar and Planetary Institute in Texas.


News Article | February 15, 2017
Site: cen.acs.org

Carbon dioxide emitted from humans and other mammals is a well-known homing beacon for blood-thirsty female mosquitoes. But mosquitoes responsible for spreading the parasite that causes malaria, Plasmodium falciparum, are more attracted to already infected animals. Ingrid Faye and colleagues at Stockholm University now report that (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP), a molecule made by P. falciparum, explains this mysterious attraction that helps spread malaria. They showed that mosquitoes preferred to consume red blood cells laced with HMBPP, doubling their intake compared with HMBPP-free cells. “It was a very fast feeding and they filled their guts enormously,” Faye says. Blood cells infected with P. falciparum caused a similar increase in feeding (Science 2017, DOI: 10.1126/science.aah4563). By analyzing the volatiles emitted from red blood cells, the researchers showed that HMBPP raised CO emissions by 16%. The molecule also increased the release of aldehydes, such as octanal, nonanal, and decanal, as well as monoterpenes, such as α-pinene, β-pinene, and limonene. Adding a synthetic blend of these compounds plus CO to blood cells had the same mosquito-enticing effect as HMBPP. The scientists also determined that HMBPP altered transcription of genes expressed in mosquito neurons, suggesting that the parasite molecule further influences mosquito behavior and blood-seeking preferences. Faye hopes to investigate HMBPP’s nervous system effects in future studies.

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