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191.
Clemens Benjamin J. Weitkamp Laurie Siwicke Kevin Wade Joy Harris Julianne Hess Jon Porter Laurie Parker Keith Sutton Trent Orlov Alexei M. 《Reviews in Fish Biology and Fisheries》2019,29(4):767-788
Reviews in Fish Biology and Fisheries - Pacific lamprey Entosphenus tridentatus has an anadromous life cycle that begins with larvae that filter-feed in freshwater, followed by transformation into... 相似文献
192.
Gregory B. Noe Meghan Q.N. Fellows Lorraine Parsons Janelle West John Callaway Sally Trnka Mark Wegener Joy Zedler 《Restoration Ecology》2019,27(4):750-757
In theory, extirpated plant species can be reintroduced and managed to restore sustainable populations. However, few reintroduced plants are known to persist for more than a few years. Our adaptive‐management case study illustrates how we restored the endangered hemiparasitic annual plant, Chloropyron maritimum subsp. maritimum (salt marsh bird's beak), to Sweetwater Marsh, San Diego Bay National Wildlife Refuge, California, United States, and used monitoring and experimentation to identify the factors limiting the reintroduced population. After extirpation in 1988, reintroduction starting that year led to a resilient, genetically diverse population in 2016 (a “boom” of approximately 14,000) that rebounded from a “bust” (62 in 2014). Multiple regressions attributed 82% of the variation in population counts to tidal amplitude, rainfall, and temperature. Populations of salt marsh bird's beak crashed when the diurnal tide range peaked during the 18.6‐year lunar nodal cycle (a rarely considered factor that periodically added approximately 12 cm to tidal ranges). We explain booms as follows: During smaller tidal amplitudes, above‐average rainfall could desalinize upper intertidal soils and stimulate salt marsh bird's beak germination. Then, moderate temperature in May favors growth to reproduction in June. In addition, salt marsh bird's beak needs a short and open canopy of native perennial plants, with roots to parasitize (not non‐native annual grass pseudohosts) and nearby upland soil for a preferred pollinator, ground‐burrowing bees. Although our reintroduced salt marsh bird's beak population is an exceptional case of persistence, this rare species‐specific environmental and biological requirement makes it vulnerable to rising sea levels and global warming. 相似文献
193.
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195.
Núñez NP Carpenter CL Perkins SN Berrigan D Jaque SV Ingles SA Bernstein L Forman MR Barrett JC Hursting SD 《Obesity (Silver Spring, Md.)》2007,15(8):1980-1987
Objective: To evaluate the effects of body adiposity on bone mineral density in the presence and absence of ovarian hormones in female mice and postmenopausal women. Research Methods and Procedures: We assessed percentage body fat, serum leptin levels, and bone mineral density in ovariectomized and non‐ovariectomized C57BL/6 female mice that had been fed various calorically dense diets to induce body weight profiles ranging from lean to very obese. Additionally, we assessed percentage body fat and whole body bone mineral density in 37 overweight and extremely obese postmenopausal women from the Women's Contraceptive and Reproductive Experiences study. Results: In mice, higher levels of body adiposity (>40% body fat) were associated with lower bone mineral density in ovariectomized C57BL/6 female mice. A similar trend was observed in a small sample of postmenopausal women. Discussion: The complementary studies in mice and women suggest that extreme obesity in postmenopausal women may be associated with reduced bone mineral density. Thus, extreme obesity (BMI > 40 kg/m2) may increase the risk for osteopenia and osteoporosis. Given the obesity epidemic in the U.S. and in many other countries, and, in particular, the rising number of extremely obese adult women, increased attention should be drawn to the significant and interrelated public health issues of obesity and osteoporosis. 相似文献
196.
Background
Media depictions of violence, although often claimed to induce viewer aggression, have not been shown to affect the cortical networks that regulate behavior.Methodology/Principal Findings
Using functional magnetic resonance imaging (fMRI), we found that repeated exposure to violent media, but not to other equally arousing media, led to both diminished response in right lateral orbitofrontal cortex (right ltOFC) and a decrease in right ltOFC-amygdala interaction. Reduced function in this network has been previously associated with decreased control over a variety of behaviors, including reactive aggression. Indeed, we found reduced right ltOFC responses to be characteristic of those subjects that reported greater tendencies toward reactive aggression. Furthermore, the violence-induced reduction in right ltOFC response coincided with increased throughput to behavior planning regions.Conclusions
These novel findings establish that even short-term exposure to violent media can result in diminished responsiveness of a network associated with behaviors such as reactive aggression. 相似文献197.
Proposed minimum reporting standards for chemical analysis 总被引:4,自引:0,他引:4
Lloyd W. Sumner Alexander Amberg Dave Barrett Michael H. Beale Richard Beger Clare A. Daykin Teresa W.-M. Fan Oliver Fiehn Royston Goodacre Julian L. Griffin Thomas Hankemeier Nigel Hardy James Harnly Richard Higashi Joachim Kopka Andrew N. Lane John C. Lindon Philip Marriott Andrew W. Nicholls Michael D. Reily John J. Thaden Mark R. Viant 《Metabolomics : Official journal of the Metabolomic Society》2007,3(3):211-221
There is a general consensus that supports the need for standardized reporting of metadata or information describing large-scale
metabolomics and other functional genomics data sets. Reporting of standard metadata provides a biological and empirical context
for the data, facilitates experimental replication, and enables the re-interrogation and comparison of data by others. Accordingly,
the Metabolomics Standards Initiative is building a general consensus concerning the minimum reporting standards for metabolomics
experiments of which the Chemical Analysis Working Group (CAWG) is a member of this community effort. This article proposes
the minimum reporting standards related to the chemical analysis aspects of metabolomics experiments including: sample preparation,
experimental analysis, quality control, metabolite identification, and data pre-processing. These minimum standards currently
focus mostly upon mass spectrometry and nuclear magnetic resonance spectroscopy due to the popularity of these techniques
in metabolomics. However, additional input concerning other techniques is welcomed and can be provided via the CAWG on-line
discussion forum at or . Further, community input related to this document can also be provided via this electronic forum.
The contents of this paper do not necessarily reflect any position of the Government or the opinion of the Food and Drug Administration
Sponsor: Metabolomics Society http://www.metabolomicssociety.org/
Reference: http://msi-workgroups.sourceforge.net/bio-metadata/reporting/pbc/
http://msi-workgroups.sourceforge.net/chemical-analysis/
Version: Revision: 5.1
Date: 09 January, 2007 相似文献
198.
Janvier Amy Joy Ulyshen Michael D. Braman Charles A. Traylor Clayton Edelkind-Vealey Miriam Braman S. Kristine 《Journal of Insect Conservation》2022,26(4):697-709
Journal of Insect Conservation - As urbanization continues throughout much of the world, there is great interest in better understanding the value of urban and residential environments to... 相似文献
199.
There is a major concern for the fate of Amazonia over the coming century in the face of anthropogenic climate change. A key area of uncertainty is the scale of rainforest dieback to be expected under a future, drier climate. In this study, we use the middle Holocene (ca. 6000 years before present) as an approximate analogue for a drier future, given that palaeoclimate data show much of Amazonia was significantly drier than present at this time. Here, we use an ensemble of climate and vegetation models to explore the sensitivity of Amazonian biomes to mid-Holocene climate change. For this, we employ three dynamic vegetation models (JULES, IBIS, and SDGVM) forced by the bias-corrected mid-Holocene climate simulations from seven models that participated in the Palaeoclimate Modelling Intercomparison Project 3 (PMIP3). These model outputs are compared with a multi-proxy palaeoecological dataset to gain a better understanding of where in Amazonia we have most confidence in the mid-Holocene vegetation simulations. A robust feature of all simulations and palaeodata is that the central Amazonian rainforest biome is unaffected by mid-Holocene drought. Greater divergence in mid-Holocene simulations exists in ecotonal eastern and southern Amazonia. Vegetation models driven with climate models that simulate a drier mid-Holocene (100–150 mm per year decrease) better capture the observed (palaeodata) tropical forest dieback in these areas. Based on the relationship between simulated rainfall decrease and vegetation change, we find indications that in southern Amazonia the rate of tropical forest dieback was ~125,000 km2 per 100 mm rainfall decrease in the mid-Holocene. This provides a baseline sensitivity of tropical forests to drought for this region (without human-driven changes to greenhouse gases, fire, and deforestation). We highlight the need for more palaeoecological and palaeoclimate data across lowland Amazonia to constrain model responses. 相似文献
200.
Igor Prudovsky Damien Carter Doreen Kacer Monica Palmeri Tee Soul Chloe Kumpel Kathleen Pyburn Karyn Barrett Victoria DeMambro Ilya Alexandrov Irina Brandina Robert Kramer Joseph Rappold 《Journal of cellular physiology》2019,234(11):19121-19129
Damage-associated molecular patterns, including mitochondrial DNA (mtDNA) are released during hemorrhage resulting in the development of endotheliopathy. Tranexamic acid (TXA), an antifibrinolytic drug used in hemorrhaging patients, enhances their survival despite the lack of a comprehensive understanding of its cellular mechanisms of action. The present study is aimed to elucidate these mechanisms, with a focus on mitochondria. We found that TXA inhibits the release of endogenous mtDNA from granulocytes and endothelial cells. Furthermore, TXA attenuates the loss of the endothelial monolayer integrity induced by exogenous mtDNA. Using the Seahorse XF technology, it was demonstrated that TXA strongly stimulates mitochondrial respiration. Studies using Mitotracker dye, cells derived from mito-QC mice, and the ActivSignal IPAD assay, indicate that TXA stimulates biogenesis of mitochondria and inhibits mitophagy. These findings open the potential for improvement of the strategies of TXA applications in trauma patients and the development of more efficient TXA derivatives. 相似文献