News Article | February 15, 2017
Conservationists need to adopt a critical shift in thinking to keep the Earth's ecosystems diverse and useful in an increasingly "unnatural" world. That was among the conclusions of conservationists from every continent but Antarctica who gathered at the University of California, Berkeley in September 2015 to discuss the future of conservation. The meeting included a diverse mix of countries and of specialists, including ecologists, conservation biologists, paleobiologists, geologists, lawyers, policymakers and writers. Their discussions, summarized and published in Science on Feb. 9, recommend a more vigorous application of information garnered from the fossil record to forward-thinking conservation efforts. Their thinking goes like this: If conservationists reach back in history far enough, the past will suggest not only how ecosystems were once composed, but how they could best function in the future. Those at the meeting also said that conservationists must take a wider view of nature than they may have in the past. This still means, in many cases, saving individual species or attempting to maintain some ecosystems much as they are, which is how conservation is generally perceived. But it also means accepting that not all human uses of the environment are inherently bad. "Changed landscapes aren't necessarily trashed landscapes," said Anthony Barnosky, executive director of Stanford's Jasper Ridge Biological Preserve, professor emeritus of integrative biology at UC Berkeley and senior author of the Science paper. "These landscapes can actually be used to help in nature conservation. The question is, how do you best do that?" Also among the Science co-authors is Alexis Mychajliw, a Stanford biology researcher who does fieldwork in the Dominican Republic and whose work exemplifies the new recommended approach to conservation. She explores the fossil record of the island nation to see what its ecosystems were like both before European settlers and before any human habitation. The comparisons between these previous states and the present day can be striking. "Where I work, you only see two living terrestrial mammal species," said Mychajliw, a graduate student in the laboratory of Stanford biology professor Elizabeth Hadly, who is also a co-author of the paper. "But if you dig, actually dig in the dirt, you'll find there were once 25 species of mammals native to this area." This is just one instance of how the fossil record can fill in blanks in natural history that conservationists may be unaware are even missing. Rather than rely on reports or conjecture about what the natural world was like 500 years ago, specialists can piece together what it was like during various periods stretching back millions of years. Given that some natural cycles work on these grand timescales, going back even further than centuries helps explain how cycles may overlap and interact now and in the future. In turn, that can reveal apparent shifts in the natural world that are worthy of concern. Having access to what an ecosystem looked like at different periods in the past also suggests options for creating, achieving and maintaining conservation goals. Already, about 47 percent of ice-free land in the world has been transformed into what ecologists call "novel ecosystems." These ecosystems are unique assemblages of species or systems that didn't exist in pre-industrial times and include cropland, pastureland and timber plantations. The Science paper ("Merging Paleobiology with Conservation Biology to Guide the Future of Terrestrial Ecosystems") points out that these novel ecosystems are unlikely to be restored to what they were before humans. That may not be a bad thing. Instead, the authors suggest that there may be cases where conservationists should embrace novelty to understand how to move forward while supporting both natural diversity and civilization. An example is Stanford's Jasper Ridge Biological Preserve, says Hadly, who is the preserve's faculty director. "Here we have a landscape that humans have used heavily for centuries," she said. "The species that dominate have changed through time, some of them invasives, but it still preserves a remarkable slice of California biodiversity and offers a refuge of nature in the midst of Silicon Valley. Going into the future, we expect more change, but that doesn't lessen its conservation value." Whether an area is novel or historical, the paper argues that conservationists need to carefully consider the services provided by an ecosystem, including air and water purification, carbon sequestration, use of land for agriculture and tourism and the less tangible value of human interactions with the wild. "We rely on nature for almost everything: clean water, food, materials for construction and making computers and phones," said Allison Stegner, postdoctoral research associate at the University of Wisconsin-Madison, former graduate student at UC Berkeley and co-author of the paper. "The pace of global change today is so fast that we stand to lose all of those things that we rely on. Coming up with new approaches to conservation is essential to maintaining human life." The authors say keeping nature diverse, healthy and useful will likely require both historical and novel habitats, efforts that focus on saving species and efforts that don't, input from people who use nature for different purposes and data from very long timescales, some of which can only be obtained through the fossil record. They also said that identifying stakes and stakeholders is a task that goes beyond the sciences. With that in mind, the workshop that led to the paper opened with words from non-scientists, including a senior policy adviser to California Gov. Jerry Brown and a fiction writer who is also the mother of one of the researchers. "They fostered a more humanist approach to our collaboration that lingers," said Hadly. Co-authors of this paper include Patrick Gonzalez, Jason Head, P. David Polly, A. Michelle Lawing, Jussi T. Eronen, David D. Ackerly, Ken Alex, Eric Biber, Jessica Blois, Justin Brashares, Gerardo Ceballos, Edward Davis, Gregory P. Dietl, Rodolfo Dirzo, Holly Doremus, Mikael Fortelius, Harry Greene, Jessica Hellmann, Thomas Hickler, Stephen T. Jackson, Melissa Kemp, Paul L. Koch, Claire Kremen, Emily L. Lindsey, Cindy Looy, Charles R. Marshall, Chase Mendenhall, Andreas Mulch, Carsten Nowak, Uma Ramakrishnan, Jan Schnitzler, Kashish Das Shrestha, Katherine Solari, Lynn Stegner, Nils Chr. Stenseth, Marvalee H. Wake, and Zhibin Zhang. During this research, Barnosky was in the Department of Integrative Biology and Museums of Paleontology and Vertebrate Zoology, University of California, Berkeley. Hadly is also the Paul S. and Billie Achilles Professor in Environmental Biology, senior fellow at the Stanford Woods Institute for the Environment, faculty director of Jasper Ridge Biological Preserve and a member of Stanford Bio-X. Stegner received her B.S. in Ecology and Evolutionary Biology from Stanford in 2010. This workshop was funded by the Integrative Climate Change Biology Group, International Union of Biological Sciences; the Museum of Paleontology, Berkeley Initiative for Global Change Biology, and Office of the Vice Chancellor for Research at the University of California, Berkeley; the Conservation Paleobiology Group at the Department of Biology, Stanford University; and the Senckenberg Biodiversity and Climate Research Centre, Frankfurt, Germany. Additional funding for this work came from the National Science Foundation.
Hassan M.N.,Bangladesh Agricultural University |
Rahman M.,Bangladesh Agricultural University |
Hossain M.B.,Noakhali Science and Technology University |
Hossain M.B.,Biology Group |
And 3 more authors.
Egyptian Journal of Aquatic Research | Year: 2013
Presence of nitrofuran and chloramphenicol in farmed prawn and shrimp is a major concern in the export sector of Bangladesh. Rejections of consignments by the foreign buyers have been recurrent for the last couple of years due to detection of these banned antibiotics. The increasingly complex requirements for food safety assurance and traceability set by major export markets represent a threat to the trade of this significant sector. In this study, the status and trends of the presence of nitrofuran and chloramphenicol in freshwater prawn Macrobrachium rosenbergii (De Man) and marine shrimp Penaeus monodon (Fabricius) and in their feeds in the Southwest coastal region of Bangladesh were investigated. The prawn/shrimp farmers, feed manufacturers and feed sellers were interviewed with well structured pre-tested Questionnaires. Antibiotic residues present in the animal muscles, feeds and feed ingredients were detected using LC-MS-MS by the Fish Inspection and Quality Control Wing of the Department of Fisheries. The study reveals that farmers did not deliberately use those banned antibiotics, but these chemicals were detected in many M. rosenbergii and P. monodon samples in 2008, 2009 and 2010, in both fresh muscles, pre-export and post-export consignments. The percentage of contamination with this banned antibiotics in M. rosenbergii samples were 17.74%, 22.89%, 13.60% and in P. monodon samples were 12.65%, 15.79%, 11.85% in 2008, 2009 and 2010 respectively. Antibiotic residue data of 2008, 2009 and 2010 showed: (i) contamination of nitrofuran and chloramphenicol was more in M. rosenbergii than P. monodon; (ii) among four nitrofuran metabolites, nitrofurazone was found more frequently but in smaller quantities in 2009 and 2010; (iii) contamination of nitrofuran metabolites was more in prawns fed with commercial feed than those with home-made feed; and (iv) there has been a decreasing trend of the presence of nitrofuran and chloramphenicol in prawn and shrimp of Bangladesh. © 2013 .
Feridoon Abbasnejad,Tabriz University of Medical Sciences |
Shoja M.M.,Tabriz University of Medical Sciences |
Shoja M.M.,Childrens Hospital |
Shoja M.M.,University of Alabama at Birmingham |
And 6 more authors.
Child's Nervous System | Year: 2012
Introduction Following the Mongolian invasion of the Middle East in the thirteenth century, a regional power called the Ilkhanid emerged and was ruled by the heirs of Temujin from Mongolia. Embracing present-day Iran, Iraq, Afghanistan, Azerbaijan, areas of Russia, Turkey, and Pakistan, and nearby Middle Eastern territories, the Ilkhanid state patronized medicine and various other professions. Centered in Tabriz (Tauris), a city in the northwest of present-day Iran, was a non-profit-making educational and medical complex founded by Grand Minister Rashid al-Din Fazlollah Hamadani Methods This paper reviews the literature regarding the rise and fall of the thirteenth century university and the Rabi Rashidi, emphasizing the structure of its medical school. Conclusions The background training of Rashid al-Din and his keen interest in science turned this complex, Rabi Rashidi (literally meaning the Rashidi Quarters), into a cosmopolitan university that freely trained medical scholars nationally and internationally. The possibility that Rashid al-Din was inspired by university developments in Europe is discussed. © Springer-Verlag 2012.
News Article | February 15, 2017
Scientists are joining lawyers, policymakers and writers to urge conservationists not only to save species, but also to preserve a diverse array of ecosystem structures and functions in the face of rising populations and changing climate. This could include allowing some species to disappear from some areas if that means a more resilient environment able to respond to warming temperatures and loss of habitat. Key to assessing the health of today's rapidly changing ecosystems is understanding their history, which can only be read from the fossil record, or the paleobiology of the region, the scientists argue. "In the past, conservation biology was about trying to hold everything static, to save everything just the way it is, like you have a museum collection of species," said senior author Anthony Barnosky, a professor emeritus of integrative biology at the University of California, Berkeley, who is now executive director of Stanford University's Jasper Ridge Biological Preserve. "But we are changing the planet so much that we can't expect to hold to the old norms. Already there are new normals, and in the future there will be even more new normals. So the question is: How do we do conservation biology under that scenario of really rapid change?" The answer is rethinking how to manage ecosystems, whether wilderness like Yellowstone National Park or a field of strawberries, to promote healthy change over time. "We are advocating in this paper that we have to preserve the capacity to respond to changes in a way that keeps the ecosystem healthy, which will likely involve watching species come and go, watching assemblages of species change, and in any given place, what we regard as a normal ecosystem today will not be the same 20 to 30 years down the road," Barnosky said. The ideas came from a workshop involving 41 scholars from around the world convened at UC Berkeley by an international group of collaborators in September 2015 to discuss the future of conservation. The group, which included ecologists, conservation biologists, paleobiologists, geologists, lawyers, policymakers and writers, is publishing its conclusions in a perspective paper appearing in the Feb. 10 issue of the journal Science. "Having collaborators from developing parts of the world helped us ground our ideas," said Elizabeth Hadly, a professor of biology at Stanford University and co-author of the paper. "Our ideas are well-motivated in science, but must account for the realities people living in these landscapes experience each day." Barnosky noted that conservation biologists have become split between those who want to focus on preserving ecosystems such as wilderness areas by excluding humans, and those wanting to manipulate what they refer to as "novel ecosystems" that result from human activities. The workshop group's consensus was that both perspectives are needed. Historically intact ecosystems, like parts of the Amazon, could be managed to simultaneously maximize biodiversity, a balanced food web and ecosystem services such as storing carbon or cleansing water, all the while preserving a feeling of wildness. Other ecosystems, like agricultural fields, could be managed to maximize producton without destroying the biodiversity surrounding them, as often happens with monocultures of corn, wheat or soybeans. "We rely on nature for almost everything: clean water, food, materials for construction and making computers and phones," said co-author Allison Stegner, a former UC Berkeley graduate student who is now a postdoctoral research associate at the University of Wisconsin-Madison. "The pace of global change today is so fast that we stand to lose all of those things that we rely on. Coming up with new approaches to conservation is essential to maintaining human life." Whether dealing with historically intact or novel ecosystems - the 47 percent of Earth's ice-free land that has been altered by humans - scientists need to look at the paleobiology of the region, that is, what the ecosystem looked like before humans altered it, and seek to rebuild it to some degree toward that natural balance, Barnosky said. In many cases, this may involve trying to preserve a member of the community that does a critical job, like a top carnivore, although the particular species that does the job may change through time. "One of the things we are arguing is, let's decide what we are trying to preserve and then use the paleobiological record to tell you how to preserve it. The fossil record is becoming critical in guiding nature into the future," Barnosky said. For novel ecosystems, the paleobiological record is essential because we may have to artificially rebuild a healthy ecosystem, which means knowing the jobs of each species there and making sure we have the right number of large mammals, for example, or the right balance of carnivores and herbivores. "You have to know the pieces, the functional roles and how to put species together to make an ecosystem that is going to last and maintain itself and remain healthy," Barnosky said. Other UC Berkeley co-authors of the paper are David Ackerly, Cindy Looy, Charles Marshall and Marvalee Wake of the Department of Integrative Biology; Justin Brashares of the Department of Environmental Science, Policy and Management; Holly Doremus and Eric Biber of Berkeley Law; former postdoc Emily Lindsey, now a curator at the Los Angeles County Museum; and visiting scholar Patrick Gonzalez, a climate change scientist with the National Park Service. The 2015 workshop was funded by the Integrative Climate Change Biology Group of the International Union of Biological Sciences; the Museum of Paleontology, UC Berkeley's Initiative for Global Change Biology and Office of the Vice Chancellor for Research; the Conservation Paleobiology Group in Stanford's Department of Biology; and the Senckenberg Biodiversity and Climate Research Center in Frankfurt, Germany.
PubMed | Shiraz University of Medical Sciences, Payame Noor University, Islamic Azad University at Tehran and Biology Group
Type: Journal Article | Journal: Avicenna journal of phytomedicine | Year: 2014
In this study we investigated the effects of spearmint (Mentha spicata Labiatae) on the reproductive system, fertility and number of offspring in adult male rats.Adult Wistar male rats in one control (C) and three experimental groups (I, II and III) received 0, 10, 20 and 40 mg/kg spearmint extract orally for 45 days, respectively. Following this treatment, the animals weights, and the standard weight of reproductive tissues, sperm count, sperm motility and serum testosterone concentration were measured, and reproductive tissues were examined histopathologically. To evaluate the effects of spearmint on fertility of male rats and growth of their offspring, male rats of the control and experimental groups mated with untreated female rats.RESULTS showed that spearmint did not affect the rats body and reproductive tissue weights. The sperm count, fast and slow progressive motility of sperm and serum testosterone concentration decreased while number of non-progressive sperm and immotile sperm increased in the experimental groups compared to the control group, but none of these changes were statistically significant. Histopathological studies showed no severe changes in reproductive tissues between control and experimental groups. Number and growth of offspring born from mating of male rats with untreated female rats showed no difference.We concluded that spearmint has no significant toxic effect on the reproductive system, fertility and number of offspring in adult male rats at the above mentioned dose levels. However high levels of this extract may have adverse effects on male fertility.
Rahman M.M.,University of Rajshahi |
Hossain Y.M.,University of Rajshahi |
Hossain I.M.,University of Rajshahi |
Provhat S.J.,University of Rajshahi |
And 2 more authors.
Turkish Journal of Fisheries and Aquatic Sciences | Year: 2013
The present study furnishes the comparison on the performance of different inducing agents in the induced breeding of the stinging catfish, Heteropneustes fossilis. During the study two experiments were conducted in two different hatcheries of Bangladesh. In the experiment 1, pituitary gland extract (PGE) was administered at 6 mg/kg body weight of females and 2 mg/kg body weight of males. In contrast, ovaprim was administered at 0.3 ml/kg and 0.1 ml/kg body weight of females and males, respectively. On the other hand, in case of experiment 2, PGE was administered at the same rate as experiment 1 while ovaprim was administered at 0.5 ml/kg and 0.1 ml/kg body weight of females and males, respectively and human chorionic gonadotropin (HCG) was injected at 1000 IU/kg body weight of both male and female fishes. Breeding success was found to be higher in ovaprim treated individuals in both the experiments in all aspects including latency period, ovulation rate, fertilization rate, hatching rate and incubation period compared to that of PGE and HCG induced individuals. In the ovaprim induced individuals, the latency period was within 10 hours while in PGE and HCG induced individuals, the latency period was 15 hours. In addition, the present investigation also revealed that, ovaprim is more efficient in terms of ovulation, fertilization and hatching rates when using at a rate of 0.5 ml/kg body weight of female fishes than using at a rate of 0.3 ml/kg body weight of female fishes. Results of the present study would help the hatchery managers in managing the induced breeding programs of H. fossilis and other catfishes. © Published by Central Fisheries Research Institute (CFRI) Trabzon, Turkey.
Dauchy R.T.,Tulane University |
Dauchy R.T.,Biology Group |
Xiang S.,Tulane University |
Xiang S.,Louisiana Cancer Research Consortium |
And 23 more authors.
Cancer Research | Year: 2014
Resistance to endocrine therapy is a major impediment to successful treatment of breast cancer. Preclinical and clinical evidence links resistance to antiestrogen drugs in breast cancer cells with the overexpression and/or activation of various pro-oncogenic tyrosine kinases. Disruption of circadian rhythms by night shift work or disturbed sleep-wake cycles may lead to an increased risk of breast cancer and other diseases. Moreover, light exposure at night (LEN) suppresses the nocturnal production of melatonin that inhibits breast cancer growth. In this study, we used a rat model of estrogen receptor (ERα+) MCF-7 tumor xenografts to demonstrate how altering light/dark cycles with dim LEN (dLEN) speed the development of breast tumors, increasing their metabolism and growth and conferring an intrinsic resistance to tamoxifen therapy. These characteristics were not observed in animals in which the circadian melatonin rhythm was not disrupted, or in animals subjected to dLEN if they received nocturnal melatonin replacement. Strikingly, our results also showed thatmelatonin acted both as a tumor metabolic inhibitor and a circadian-regulated kinase inhibitor to reestablish the sensitivity of breast tumors to tamoxifen and tumor regression. Together, our findings show how dLEN-mediated disturbances in nocturnal melatonin production can render tumors insensitive to tamoxifen. © 2014 American Association for Cancer Research.
PubMed | Biology Group
Type: Journal Article | Journal: TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik | Year: 2013
Leaf protoplasts isolated from haploid and dihaploid Nicotiana plumbaginifolia plantlets were treated with different doses of gamma-rays and their survival was determined by scoring for plating efficiency at each irradiation dose. A fixed number of surviving protoplast-derived colonies was then plated in the presence of inhibitory concentrations of L-valine and incubated until growing resistant calli could be scored and mutation rates calculated. Though haploid protoplasts were found to be a little more sensitive than dihaploids to the lethal effect of radiation, the two dose-response curves of gamma-rays that induced mutagenesis were very similar. The irradiation dose capable of causing a ten-fold increase of spontaneous mutation frequencies was about 500 rads with both haploid and dihaploid protoplasts.