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News Article | May 4, 2017
Site: www.enr.com

An unmanned aerial vehicle (UAV) equipped with light detection and ranging (LiDAR) technology is being tested to document cut-and-fill work on a $74-million interchange in Contra Costa County, Calif. With an equipment cost of about $150,000, the drone’s high-resolution data-capture technology will monitor the movement of 150,000 cu yd of fill, ensuring the estimated $1-million to $2-million worth of earthwork goes as efficiently as possible. “Five years ago, there was no way we could have put LiDAR on a UAV,” says Ed Greutert, principal engineer with Alta Vista Solutions, which proposed testing the technology to the Contra Costa County Transportation Authority (CCTA). “Now, a number of manufacturers are making units that are far more advanced, weighing 4 kilograms [8 lb,13 oz] or less.” A French company, Yellowscan, provides the LiDAR. Weighing 3.5 pounds and consuming 15 watts of power, the device has a precision rate of 4 sq centimeters and boasts 5-sq-cm accuracy. The scans will be used to compare contractor performance versus the plan and identify potential areas of project and performance risk. The data will be used to verify fill-invoice amounts, track materials inventory, and support project scheduling and change-order documentation. It also will be used to monitor stormwater runoff and other environmental conditions, as well as identify potential safety risks and evaluate changes in existing structures that may be introduced during construction. Gathering the unusually high-resolution data initially involved the drone operator repeatedly adjusting to find the optimal height and speed in a trial-and-error process. “I’d say the biggest challenge we had is collecting the data we need to generate a bare-earth digital service model,” says Greutert. “During the first month, the data was not dense enough to use for our purposes.” Another challenge is handling the massive amounts of information. “We collected 100 gigabytes of LiDAR data,” says Greutert. “Moving that around and processing it … can take several hours or overnight. Then, you tweak something and rerun the model.” To be collected over the course of the two-year project in Brentwood, the data are expected not only to maximize efficiency of the earthmoving but also help the public to see each stage of construction, says Randell Iwasaki, executive director at CCTA. “Aerial views are hard to come by. Now, we can get a video of the progress of our project. We can take a look at environmentally sensitive areas. We can show that nobody’s in there—that we are treating those areas as promised. We can ‘fly a job’ after it rains to make sure the [runoff] control systems are working as they should.” Moreover, Iwasaki adds, using the drone means surveyors don’t have to stand in live traffic in harm’s way. “We are always looking for ways to be efficient and safer,” Iwasaki says. “Drones offer a golden opportunity. We can gather enough info from a drone, sensors, etcetera, so we know the taxpayers are getting their money’s worth.” The CCTA last fall awarded the $37-million construction contract to a joint venture of Brosamer & Wall Inc. and Bay Cities Paving & Grading. The project is the concluding chapter of the Highway 4 program, a $1-billion endeavour to improve mobility in the region.


Barreto P.A.B.,State University of Norte Fluminense | Gama-Rodrigues E.F.,CCTA | Gama-Rodrigues A.C.,CCTA | de Barros N.F.,Federal University of Viçosa | Fonseca S.,Fibria Celulose S.A
Revista Brasileira de Ciencia do Solo | Year: 2010

To maximize the efficiency of N uptake by plants it is important to study N and C mineralization, particularly in the case of eucalyptus, which has a very low response to nitrogen fertilization. The rates of C and N mineralization and C and N mineralization potential were estimated, in soils under 1, 3, 5, and 13 year-old eucalyptus plantations with similar soil and climatic conditions. Soil from the 0-10 cm layer was sampled in November 2003. The samples were incubated under aerobic laboratory conditions for successive periods of 1, 1, 1, 2, 2, 4, 4, 4 weeks in a total of 19 weeks. The mineralized N was periodically extracted and determined colorimetrically, and the mineralized C was determined based on C-CO 2 evolution. The average accumulated N was 58 mg kg -1 soil and it did not differ significantly among ages. Potentially mineralizable N (N o) varied between 58 to 87 mg kg -1soil, which represented 3.4 to 5.2% of soil N (Ns); according to No:Ns ratio. N-NH 4 + was the predominant form of mineral N. The mineralized C differed significantly among ages (606 to 1,122 mg kg -1 C-CO 2 soil). The average potentially mineralizable C (C o) was 862 mg kg -1 C-CO 2 soil, representing 3.4% of soil organic C (Corg) according to the C o:Corg ratio. The rate and mineralization potential of C and N were not influenced by the age of the plantations. The pool of potentially mineralizable N could meet the N demand of eucalyptus in future rotations.


News Article | February 21, 2017
Site: www.eurekalert.org

LOS ANGELES - (Feb. 21, 2017) - A new study suggests testosterone treatments may increase the risk of heart disease in older men. It found a 20% increase in arterial plaque among men aged 65 and older who received testosterone replacement therapy for a year, according to the study published today in the Journal of the American Medical Association (JAMA). The multicenter study followed 138 men enrolled in the Testosterone Trials (TTrials), a National Institutes of Health (NIH) funded clinical research trial to determine if testosterone treatment of men aged 65 and older will help their walking, vitality, sexual function, memory, blood count and cardiovascular risk. The researchers reported that the men who received a placebo had just a 1% rise in plaque volumes, while the men who received the testosterone treatments for a year had a 20% increase in total coronary and noncalcified plaque volumes as measured with coronary computed tomographic arteriography (CCTA). "Heart disease remains the No. 1 cause of death in the U. S., and measuring coronary artery atherosclerosis has become a most effective method for evaluating cardiovascular risk," said Matthew J. Budoff, MD, a cardiologist who is an LA BioMed lead researcher and the primary author of the study. "While physicians are increasingly prescribing testosterone replacement for their older male patients, recent studies had reached conflicting conclusions about the potential cardiovascular risks. This finding of a significant increase in plaque volumes among men undergoing testosterone treatments indicates they may face a potentially increased risk of heart disease. However, longer-term research is needed to determine the actual risk." Dr. Budoff was the principal investigator for the study, and Drs. Ronald Swerdloff and Christina Wang, endocrinologists who are also LA BioMed lead researchers, were also investigators and authors of the study. It is one of four studies published today from the TTrials, a coordinated group of seven trials conducted by a team of researchers from LA BioMed and 12 other medical centers in the U.S., in partnership with the National Institute on Aging. "While our previous research has found some benefits from testosterone treatments, this latest study should provide important guidance for physicians and their patients," said Dr. Budoff. "Men who have underlying coronary artery disease or studies showing elevated arterial plaque levels should discuss carefully with their physicians the benefits and risks of testosterone therapy before initiating it or continuing the therapy." These results indicate the need for a larger and longer trial to determine actual risk of testosterone replacement. The study is one of four studies examining testosterone therapy that were published today in JAMA and JAMA Internal Medicine. In addition to the LA BioMed researchers, the authors of this study are: Susan S. Ellenberg, PhD; Cora E Lewis, MD, MSPH; Emile R Mohler III, MD; Nanette K Wenger, MD, MACC, MACP, FAHA; Shalender Bhasin, MD; Elizabeth Barrett-Connor, MD; Alisa Stephens-Shields, PhD; Jane A Cauley, DrPH; Jill P Crandall, MD; Glenn R Cunningham, MD; Kristine E Ensrud, MD, MPH; Thomas M. Gill, MD; Alvin M Matsumoto, MD; Mark E Molitch, MD; Rine Nakanishi, MD; Negin Nezarat, MD; Suguru Matsumoto, MD; Xiaoling Hou, MS; Shehzad Basaria, MD; Susan J. Diem, MD, MPH; Denise Cifelli, MS, and Peter J. Snyder, MD. Founded in 1952, LA BioMed is one of the country's leading nonprofit independent biomedical research institutes. It has approximately 100 principal researchers conducting studies into improved treatments and therapies for cancer, inherited diseases, infectious diseases, illnesses caused by environmental factors and more. It also educates young scientists and provides community services, including prenatal counseling and childhood nutrition programs. LA BioMed is academically affiliated with the David Geffen School of Medicine at UCLA and located on the campus of Harbor-UCLA Medical Center. For more information, please visit http://www.


News Article | November 29, 2016
Site: www.eurekalert.org

CHICAGO - Researchers using coronary computed tomography angiography (CCTA) have found no association between light to moderate alcohol consumption and coronary artery disease (CAD), according to a study being presented today at the annual meeting of the Radiological Society of North America (RSNA). Some previous studies have suggested that light alcohol consumption may actually reduce the risk for CAD. However, data regarding regular alcohol consumption and its association with the presence of CAD remains controversial. For the new study, researchers looked at alcohol consumption, type of alcohol consumed, and presence of coronary plaques using CCTA. "CCTA is an excellent diagnostic modality to noninvasively depict the coronary wall and identify atherosclerotic lesions," said study author Júlia Karády, M.D., from the MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center at Semmelweis University in Budapest, Hungary. "Furthermore, we're able to characterize plaques and differentiate between several types. Prior studies used cardiovascular risk factors--like high cholesterol levels--and cardiovascular outcomes to study the effects of alcohol, but our study is unique in that we analyzed both drinkers and non-drinkers using CCTA, which may shed some light on how alcohol may or may not contribute to the development of fatty plaques in the arteries of the heart." The researchers studied 1,925 consecutive patients referred for CCTA with suspected CAD. Information on alcohol consumption habits was collected using questionnaires about the amount and type of alcohol consumed. Using an in-house reporting platform that contained the patients' clinical and CCTA data, researchers were able to assess the relationship between atherosclerosis, clinical risk factors and patient drinking habits. "About 40 percent of our patients reported regular alcohol consumption, with a median of 6.7 alcohol units consumed weekly," Dr. Karády said. One unit translates to approximately 2 deciliters (dl) or 6.8 fluid ounces of beer, 1 dl or 3.4 ounces of wine, or 4 centiliters (cl) or 1.35 ounces of hard liquor. The results showed that the amount of weekly alcohol consumption, whether light or moderate, was not associated with the presence of CAD. In addition, when researchers looked at different types of alcohol and the presence of coronary atherosclerosis, no associations were found. "When we compared consumption between patients who had coronary artery plaques and those who had none, no difference was detected," Dr. Karády said. "Evaluating the relationship between light alcohol intake (maximum of 14 units per week) and presence of CAD, we again found no association. Furthermore, we analyzed the effect of different types of alcohol (beer, wine and hard liquor) on the presence of CAD, but no relationship was found." Dr. Karády added that while no protective effect was detected among light drinkers, as previously thought, no harmful effects were detected either. The researchers are in the process of expanding the study to include more patients and perform further analyses. Independently of whether alcohol has any effect on the coronary arteries, moderate alcohol consumption has been associated with a number of potential side effects, including negative long-term effects on the brain and heart. Co-authors on this study were Balint Szilveszter, M.D., Zsofia D. Drobni, M.D., Marton Kolossvary, M.D., Andrea Bartykowszki, M.D., Mihaly Karolyi, M.D., Ph.D., Adam Jermendy, M.D., Alexisz Panajotu, M.D., Zsolt Bagyura, M.D., and Pal Maurovich-Horvat, M.D., Ph.D., M.P.H. Note: Copies of RSNA 2016 news releases and electronic images will be available online at RSNA.org/press16 beginning Monday, Nov. 28. RSNA is an association of more than 54,000 radiologists, radiation oncologists, medical physicists and related scientists, promoting excellence in patient care and health care delivery through education, research and technologic innovation. The Society is based in Oak Brook, Ill. (RSNA.org)


Ferreira J.A.M.,University of Coimbra | Reis P.N.B.,CCTA | Costa J.D.M.,University of Coimbra | Richardson B.C.H.,CTA Ltd. | Richardson M.O.W.,CTA Ltd.
Composites Part B: Engineering | Year: 2011

This paper presents the results of a current study concerned with the mechanical properties of a polypropylene binder resin, enhanced by nanoclay filler. The study was centred on the potential benefits obtained by the addition of specially surface treated nanoclays on the stiffness, toughness and also on static and fatigue strength. Specimens were produced by an injection moulding process with 3% in weight of nanoclay. Surface treatment of the nanoclay promotes a tendency to increase stiffness and tensile strength in comparison with composites filled by both commercial nanoclay and unfilled material. Nanoclay filling significantly improves absorbed impact energy in comparison with unfilled materials, but in contrast Gc values are significantly lower as consequence of the material embrittlement. Fatigue analysis shows that the materials tested in the present work exhibit high strain accumulation and stress release. Filled material show lower fatigue performance than unfilled polymer. However, surface treatment used on B3 composite promotes better clay dispersion and smaller particle size leading to a fatigue performance close to matrix polymer. © 2011 Elsevier Ltd. All rights reserved.


News Article | November 29, 2016
Site: www.prnewswire.com

CHICAGO, Nov. 29, 2016 /PRNewswire-USNewswire/ -- Researchers using coronary computed tomography angiography (CCTA) have found no association between light to moderate alcohol consumption and coronary artery disease (CAD), according to a study being presented today at the annual meeting...


do Amaral T.L.,CCTA | Jasmim J.M.,Laboratorio Of Fitotecnia Do Ccta | Araujo J.S.P.,Federal Rural University of Rio de Janeiro | Thiebaut J.T.L.,LEAG | And 2 more authors.
Ciencia e Agrotecnologia | Year: 2010

The research objective was to evaluate the efficiency of substrates and fertilization levels on the growth and leaf nutrient contents of orchid hybrids of the genus Phalaenopsis. The study consisted of two experiments in carried out with industrialized coconut fiber (Sub 1) and non-industrialized coconut fiber (Sub 2), in mixture with Pinus bark and grade zero gravel (1:1:1 v/v/v) in randomized blocks. The first experiment in a split-plot scheme in time (6 and 12 months) with five replications, evaluated the hybrid RJ 343, in both substrates, under four levels of mineral fertilizer (0; 0.9; 1.2; 1.5 g L-1) and two additional treatments [leaf application of Aminon® (0.5 ml L-1) at 1.2 g L-1, in Sub1 and Sub 2]. The second one evaluated the hybrid RJ 84-2, in both substrates, with the same mineral fertilizer levels and leaf application of Aminon® (0 e 0.5 ml L-1), in a split-split-split plot scheme in time (6 and 12 months) with three replications. The number of leaves, leaf area, superficial root area, leaf, root and total dry weight, and N, P and K leaf contents were evaluated. Aminon® had no effect on the growth of the hybrids. Increase in fertilization led to increased growth, except for roots, with greater growth being observed at 1.5 g L-1 of mineral fertilizer. The Sub 2 caused greater growth of plants of the hybrid RJ 343, whereas the Sub 1 led to greater growth of the hybrid RJ 84-2.


SAN FRANCISCO, Nov. 29, 2016 /PRNewswire/ -- The Metropolitan Transportation Commission (MTC), Caltrans, the Transportation Authority of Marin (TAM) and the Contra Costa Transportation Authority (CCTA) invite the public to a pair of open houses in Richmond on Thursday, Dec. 8 and in San...


Garcia C.S.,CCTA | Fernandes A.M.,State University of Norte Fluminense | Fontes C.A.A.,State University of Norte Fluminense | Vieira R.A.M.,State University of Norte Fluminense | And 2 more authors.
Revista Brasileira de Zootecnia | Year: 2011

The performance of steers raised on elephant and mombasa grass pastures was evaluated from October to December 2006. A rotational grazing system with a regulated forage offer was adopted. The experimental area consisted of two repetitions containing 18 0.25-ha paddocks divided into nine paddocks with elephant grass and nine with mombasa grass. Forage species, area repetition, the interaction among these effects, paddocks within the interaction, and the experimental error were the effects of the treatments. This model was used to analyze pasture attributes. For analyses of intake, digestibility and gain, 24 steers were randomly assigned to the respective interactions among forage vs. repetition vs. grazing system, totaling three animals per triple interaction. The grazing systems consisted of ad libitum (AL) and restricted (PR) grazing. Elephant-grass showed the highest total dry matter biomass (TB) and green leaf dry matter biomass (GLDM). There were no differences among forage plants for production of biomass of green leaf dry matter; leaf proportion was the greatest in mombasa grass, however. Extrusas showed similar bromatological composition. Only crude protein intake, which was the highest for mombasa pasture, differed among forage plants. Ad libitum feeding enabled a higher intake of all nutrients from both pastures. Digestibility of nutrients was higher for elephant-grass but it did not differ among feeding levels: only crude protein content was the highest on pasture where grazing was restrict and gross energy content of pasture was higher for ad libitum grazing system. Despite qualitative and quantitative differences among forage plants, differences of weight gain per animal and per area were not found. For animal with ad libitum feeding, average body mass gain was 850 g/day and gain per area was 246 kg/ha during the experimental period. © 2011 Sociedade Brasileira de Zootecnia.


News Article | November 30, 2016
Site: www.sciencedaily.com

Researchers using coronary computed tomography angiography (CCTA) have found no association between light to moderate alcohol consumption and coronary artery disease (CAD).

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