Showing papers by "University of New Mexico published in 2008"
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TL;DR: A hydraulically based theory considering carbon balance and insect resistance that allowed development and examination of hypotheses regarding survival and mortality was developed, and incorporating this hydraulic framework may be effective for modeling plant survival andortality under future climate conditions.
Abstract: Summary Severe droughts have been associated with regional-scale forest mortality worldwide. Climate change is expected to exacerbate regional mortality events; however, pre- diction remains difficult because the physiological mechanisms underlying drought survival and mortality are poorly understood. We developed a hydraulically based theory considering carbon balance and insect resistance that allowed development and examination of hypotheses regarding survival and mortality. Multiple mechanisms may cause mortality during drought. A common mechanism for plants with isohydric
3,302 citations
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TL;DR: The brief resilience scale (BRS) is a reliable means of assessing resilience as the ability to bounce back or recover from stress and may provide unique and important information about people coping with health-related stressors.
Abstract: Background: While resilience has been defined as resistance to illness, adaptation, and thriving, the ability to bounce back or recover from stress is closest to its original meaning. Previous resilience measures assess resources that may promote resilience rather than recovery, resistance, adaptation, or thriving. Purpose: To test a new brief resilience scale. Method: The brief resilience scale (BRS) was created to assess the ability to bounce back or recover from stress. Its psychometric characteristics were examined in four samples, including two student samples and samples with cardiac and chronic pain patients. Results: The BRS was reliable and measured as a unitary construct. It was predictably related to personal characteristics, social relations, coping, and health in all samples. It was negatively related to anxiety, depression, negative affect, and physical symptoms when other resilience measures and optimism, social support, and Type D personality (high negative affect and high social inhibition) were controlled. There were large differences in BRS scores between cardiac patients with and without Type D and women with and without fibromyalgia. Conclusion: The BRS is a reliable means of assessing resilience as the ability to bounce back or recover from stress and may provide unique and important information about people coping with health-related stressors.
3,285 citations
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Curtin University1, University of Western Australia2, Lund University3, University of Adelaide4, Geological Survey of Canada5, Carleton University6, University of Brasília7, University of Bergen8, University of New Mexico9, Macquarie University10, Stockholm University11, University of Copenhagen12, Russian Academy of Sciences13
TL;DR: A brief synthesis of the current state of knowledge on the formation and break-up of the early Neoproterozoic supercontinent Rodinia and the subsequent assembly of Gondwanaland is presented in this paper.
2,790 citations
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Daniel J. Klionsky1, Hagai Abeliovich2, Patrizia Agostinis3, Devendra K. Agrawal4 +232 more•Institutions (137)
TL;DR: A set of guidelines for the selection and interpretation of the methods that can be used by investigators who are attempting to examine macroautophagy and related processes, as well as by reviewers who need to provide realistic and reasonable critiques of papers that investigate these processes are presented.
Abstract: Research in autophagy continues to accelerate,(1) and as a result many new scientists are entering the field Accordingly, it is important to establish a standard set of criteria for monitoring macroautophagy in different organisms Recent reviews have described the range of assays that have been used for this purpose(2,3) There are many useful and convenient methods that can be used to monitor macroautophagy in yeast, but relatively few in other model systems, and there is much confusion regarding acceptable methods to measure macroautophagy in higher eukaryotes A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers of autophagosomes versus those that measure flux through the autophagy pathway; thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from fully functional autophagy that includes delivery to, and degradation within, lysosomes (in most higher eukaryotes) or the vacuole (in plants and fungi) Here, we present a set of guidelines for the selection and interpretation of the methods that can be used by investigators who are attempting to examine macroautophagy and related processes, as well as by reviewers who need to provide realistic and reasonable critiques of papers that investigate these processes This set of guidelines is not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to verify an autophagic response
2,310 citations
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TL;DR: This work presents a general technique for inferring hierarchical structure from network data and shows that the existence of hierarchy can simultaneously explain and quantitatively reproduce many commonly observed topological properties of networks.
Abstract: Networks have in recent years emerged as an invaluable tool for describing and quantifying complex systems in many branches of science. Recent studies suggest that networks often exhibit hierarchical organization, in which vertices divide into groups that further subdivide into groups of groups, and so forth over multiple scales. In many cases the groups are found to correspond to known functional units, such as ecological niches in food webs, modules in biochemical networks (protein interaction networks, metabolic networks or genetic regulatory networks) or communities in social networks. Here we present a general technique for inferring hierarchical structure from network data and show that the existence of hierarchy can simultaneously explain and quantitatively reproduce many commonly observed topological properties of networks, such as right-skewed degree distributions, high clustering coefficients and short path lengths. We further show that knowledge of hierarchical structure can be used to predict missing connections in partly known networks with high accuracy, and for more general network structures than competing techniques. Taken together, our results suggest that hierarchy is a central organizing principle of complex networks, capable of offering insight into many network phenomena.
2,143 citations
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University of New Mexico1, University of Toledo2, Arizona State University3, University of California, Irvine4, University of New Hampshire5, University of California, Berkeley6, Carthage College7, University of Minnesota8, University of California, Santa Barbara9, United States Geological Survey10, Colorado State University11, University of Michigan12
TL;DR: A global-scale meta-analysis of the seven-most widely measured soil enzyme activities is conducted, indicating that the enzymatic potential for hydrolyzing the labile components of soil organic matter is tied to substrate availability, soil pH and the stoichiometry of microbial nutrient demand.
Abstract: Extracellular enzymes are the proximate agents of organic matter decomposition and measures of these activities can be used as indicators of microbial nutrient demand. We conducted a global-scale meta-analysis of the seven-most widely measured soil enzyme activities, using data from 40 ecosystems. The activities of b-1,4-glucosidase, cellobiohydrolase, b-1,4-N-acetylglucosaminidase and phosphatase g )1 soil increased with organic matter concentration; leucine aminopeptidase, phenol oxidase and peroxidase activities showed no relationship. All activities were significantly related to soil pH. Specific activities, i.e. activity g )1 soil organic matter, also varied in relation to soil pH for all enzymes. Relationships with mean annual temperature (MAT) and precipitation (MAP) were generally weak. For hydrolases, ratios of specific C, N and P acquisition activities converged on 1 : 1 : 1 but across ecosystems, the ratio of C : P acquisition was inversely related to MAP and MAT while the ratio of C : N acquisition increased with MAP. Oxidative activities were more variable than hydrolytic activities and increased with soil pH. Our analyses indicate that the enzymatic potential for hydrolyzing the labile components of soil organic matter is tied to substrate availability, soil pH and the stoichiometry of microbial nutrient demand. The enzymatic potential for oxidizing the recalcitrant fractions of soil organic material, which is a proximate control on soil organic matter accumulation, is most strongly related to soil pH. These trends provide insight into the biogeochemical processes that create global patterns in ecological stoichiometry and organic matter storage.
1,630 citations
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TL;DR: The regulatory factors that regulate DSB repair by NHEJ and HR in yeast and higher eukaryotes are reviewed, including regulated expression and phosphorylation of repair proteins, chromatin modulation of repair factor accessibility, and the availability of homologous repair templates.
Abstract: DNA double-strand breaks (DSBs) are critical lesions that can result in cell death or a wide variety of genetic alterations including large- or small-scale deletions, loss of heterozygosity, translocations, and chromosome loss. DSBs are repaired by non-homologous end-joining (NHEJ) and homologous recombination (HR), and defects in these pathways cause genome instability and promote tumorigenesis. DSBs arise from endogenous sources including reactive oxygen species generated during cellular metabolism, collapsed replication forks, and nucleases, and from exogenous sources including ionizing radiation and chemicals that directly or indirectly damage DNA and are commonly used in cancer therapy. The DSB repair pathways appear to compete for DSBs, but the balance between them differs widely among species, between different cell types of a single species, and during different cell cycle phases of a single cell type. Here we review the regulatory factors that regulate DSB repair by NHEJ and HR in yeast and higher eukaryotes. These factors include regulated expression and phosphorylation of repair proteins, chromatin modulation of repair factor accessibility, and the availability of homologous repair templates. While most DSB repair proteins appear to function exclusively in NHEJ or HR, a number of proteins influence both pathways, including the MRE11/RAD50/NBS1(XRS2) complex, BRCA1, histone H2AX, PARP-1, RAD18, DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and ATM. DNA-PKcs plays a role in mammalian NHEJ, but it also influences HR through a complex regulatory network that may involve crosstalk with ATM, and the regulation of at least 12 proteins involved in HR that are phosphorylated by DNA-PKcs and/or ATM.
1,211 citations
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University of Tennessee1, Oak Ridge National Laboratory2, University of Georgia3, University of Wyoming4, Michigan State University5, Marine Biological Laboratory6, University of Notre Dame7, Oregon State University8, University of New Mexico9, Kansas State University10, Arizona State University11, United States Department of Agriculture12, University of New Hampshire13, Virginia Tech14, Washington State University Vancouver15, Ball State University16
TL;DR: It is demonstrated that excess nitrate in streams elicits a disproportionate increase in the fraction of nitrate that is exported to receiving waters and reduces the relative role of small versus large streams as nitrate sinks.
Abstract: About a quarter of the nitrogen added to the biosphere is exported from rivers to the ocean or inland basins, indicating substantial sinks for nitrogen must exist in the landscape. Data from nitrogen stable isotope tracer experiments across 72 streams suggests that the total uptake of nitrate is related to ecosystem photosynthesis, and that denitrification is related to ecosystem respiration. A stream network model demonstrates that excess nitrate in streams elicits a disproportionate increase in the fraction of nitrate that is exported to receiving waters and reduces the relative role of small versus large streams as nitrate sinks. Anthropogenic addition of bioavailable nitrogen to the biosphere is increasing1,2 and terrestrial ecosystems are becoming increasingly nitrogen-saturated3, causing more bioavailable nitrogen to enter groundwater and surface waters4,5,6. Large-scale nitrogen budgets show that an average of about 20–25 per cent of the nitrogen added to the biosphere is exported from rivers to the ocean or inland basins7,8, indicating that substantial sinks for nitrogen must exist in the landscape9. Streams and rivers may themselves be important sinks for bioavailable nitrogen owing to their hydrological connections with terrestrial systems, high rates of biological activity, and streambed sediment environments that favour microbial denitrification6,10,11. Here we present data from nitrogen stable isotope tracer experiments across 72 streams and 8 regions representing several biomes. We show that total biotic uptake and denitrification of nitrate increase with stream nitrate concentration, but that the efficiency of biotic uptake and denitrification declines as concentration increases, reducing the proportion of in-stream nitrate that is removed from transport. Our data suggest that the total uptake of nitrate is related to ecosystem photosynthesis and that denitrification is related to ecosystem respiration. In addition, we use a stream network model to demonstrate that excess nitrate in streams elicits a disproportionate increase in the fraction of nitrate that is exported to receiving waters and reduces the relative role of small versus large streams as nitrate sinks.
1,193 citations
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TL;DR: In this paper, the authors use quantum discord to characterize the correlations present in the model called deterministic quantum computation with one quantum bit (DQC1), introduced by Knill and Laflamme [1998].
Abstract: We use quantum discord to characterize the correlations present in the model called deterministic quantum computation with one quantum bit (DQC1), introduced by Knill and Laflamme [Phys. Rev. Lett. 81, 5672 (1998)]. The model involves a collection of qubits in the completely mixed state coupled to a single control qubit that has nonzero purity. The initial state, operations, and measurements in the model all point to a natural bipartite split between the control qubit and the mixed ones. Although there is no entanglement between these two parts, we show that the quantum discord across this split is nonzero for typical instances of the DQC1 ciruit. Nonzero values of discord indicate the presence of nonclassical correlations. We propose quantum discord as figure of merit for characterizing the resources present in this computational model.
1,138 citations
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Michigan State University1, J. Craig Venter Institute2, National Institutes of Health3, Wellcome Trust Sanger Institute4, Plymouth Marine Laboratory5, University of Maryland, Baltimore6, University of Cambridge7, University of York8, United States Department of Energy9, Ghent University10, Pennsylvania State University11, Argonne National Laboratory12, University of California, San Diego13, Jacobs University Bremen14, University of Colorado Boulder15, National Science Foundation16, Edinburgh Napier University17, Boston Children's Hospital18, University of Georgia19, University of California, Berkeley20, Newcastle University21, Lawrence Berkeley National Laboratory22, University of California, Irvine23, University of Oxford24, Howard University25, Abertay University26, University of Manchester27, Technical University of Denmark28, University of Wyoming29, University of Pennsylvania30, University of New Mexico31
TL;DR: Here, the minimum information about a genome sequence (MIGS) specification is introduced with the intent of promoting participation in its development and discussing the resources that will be required to develop improved mechanisms of metadata capture and exchange.
Abstract: With the quantity of genomic data increasing at an exponential rate, it is imperative that these data be captured electronically, in a standard format. Standardization activities must proceed within the auspices of open-access and international working bodies. To tackle the issues surrounding the development of better descriptions of genomic investigations, we have formed the Genomic Standards Consortium (GSC). Here, we introduce the minimum information about a genome sequence (MIGS) specification with the intent of promoting participation in its development and discussing the resources that will be required to develop improved mechanisms of metadata capture and exchange. As part of its wider goals, the GSC also supports improving the 'transparency' of the information contained in existing genomic databases.
1,097 citations
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Los Alamos National Laboratory1, University of New Mexico2, Novozymes3, University of Provence4, VTT Technical Research Centre of Finland5, Pacific Northwest National Laboratory6, Joint Genome Institute7, United States Department of Agriculture8, Vienna University of Technology9, Pontifical Catholic University of Chile10, Oregon State University11, Genencor12
TL;DR: This work assembled 89 scaffolds to generate 34 Mbp of nearly contiguous T. reesei genome sequence comprising 9,129 predicted gene models, providing a roadmap for constructing enhanced T.Reesei strains for industrial applications such as biofuel production.
Abstract: Trichoderma reesei is the main industrial source of cellulases and hemicellulases used to depolymerize biomass to simple sugars that are converted to chemical intermediates and biofuels, such as ethanol. We assembled 89 scaffolds (sets of ordered and oriented contigs) to generate 34 Mbp of nearly contiguous T. reesei genome sequence comprising 9,129 predicted gene models. Unexpectedly, considering the industrial utility and effectiveness of the carbohydrate-active enzymes of T. reesei, its genome encodes fewer cellulases and hemicellulases than any other sequenced fungus able to hydrolyze plant cell wall polysaccharides. Many T. reesei genes encoding carbohydrate-active enzymes are distributed nonrandomly in clusters that lie between regions of synteny with other Sordariomycetes. Numerous genes encoding biosynthetic pathways for secondary metabolites may promote survival of T. reesei in its competitive soil habitat, but genome analysis provided little mechanistic insight into its extraordinary capacity for protein secretion. Our analysis, coupled with the genome sequence data, provides a roadmap for constructing enhanced T. reesei strains for industrial applications such as biofuel production.
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TL;DR: High Resolution Fly's Eye's measurement of the flux of ultrahigh energy cosmic rays shows a sharp suppression at an energy of 6 x 10(19) eV, consistent with the expected cutoff energy.
Abstract: The High Resolution Fly's Eye (HiRes) experiment has observed the Greisen-Zatsepin-Kuzmin suppression (called the GZK cutoff) with a statistical significance of five standard deviations. HiRes' measurement of the flux of ultrahigh energy cosmic rays shows a sharp suppression at an energy of $6\ifmmode\times\else\texttimes\fi{}{10}^{19}\text{ }\text{ }\mathrm{eV}$, consistent with the expected cutoff energy. We observe the ankle of the cosmic-ray energy spectrum as well, at an energy of $4\ifmmode\times\else\texttimes\fi{}{10}^{18}\text{ }\text{ }\mathrm{eV}$. We describe the experiment, data collection, and analysis and estimate the systematic uncertainties. The results are presented and the calculation of the statistical significance of our observation is described.
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TL;DR: The results support the hypothesis that collectivism (compared with individualism) will more often characterize cultures in regions that have historically had higher prevalence of pathogens, and reveal previously undocumented consequences of pathogenic diseases on the variable nature of human societies.
Abstract: Pathogenic diseases impose selection pressures on the social behaviour of host populations. In humans (Homo sapiens), many psychological phenomena appear to serve an antipathogen defence function. One broad implication is the existence of cross-cultural differences in human cognition and behaviour contingent upon the relative presence of pathogens in the local ecology. We focus specifically on one fundamental cultural variable: differences in individualistic versus collectivist values. We suggest that specific behavioural manifestations of collectivism (e.g. ethnocentrism, conformity) can inhibit the transmission of pathogens; and so we hypothesize that collectivism (compared with individualism) will more often characterize cultures in regions that have historically had higher prevalence of pathogens. Drawing on epidemiological data and the findings of worldwide cross-national surveys of individualism/collectivism, our results support this hypothesis: the regional prevalence of pathogens has a strong positive correlation with cultural indicators of collectivism and a strong negative correlation with individualism. The correlations remain significant even when controlling for potential confounding variables. These results help to explain the origin of a paradigmatic cross-cultural difference, and reveal previously undocumented consequences of pathogenic diseases on the variable nature of human societies.
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TL;DR: It is reported that a Beclin1-binding autophagic tumour suppressor, UVRAG, interacts with the class C Vps complex, a key component of the endosomal fusion machinery, and this interaction stimulates Rab7 GTPase activity and autophagosome fusion with late endosomes/lysosomes, thereby enhancing delivery and degradation of Autophagic cargo.
Abstract: Autophagic and endocytic pathways are tightly regulated membrane rearrangement processes that are crucial for homeostasis, development and disease. Autophagic cargo is delivered from autophagosomes to lysosomes for degradation through a complex process that topologically resembles endosomal maturation. Here, we report that a Beclin1-binding autophagic tumour suppressor, UVRAG, interacts with the class C Vps complex, a key component of the endosomal fusion machinery. This interaction stimulates Rab7 GTPase activity and autophagosome fusion with late endosomes/lysosomes, thereby enhancing delivery and degradation of autophagic cargo. Furthermore, the UVRAG-class-C-Vps complex accelerates endosome–endosome fusion, resulting in rapid degradation of endocytic cargo. Remarkably, autophagosome/endosome maturation mediated by the UVRAG-class-C-Vps complex is genetically separable from UVRAG–Beclin1-mediated autophagosome formation. This result indicates that UVRAG functions as a multivalent trafficking effector that regulates not only two important steps of autophagy — autophagosome formation and maturation — but also endosomal fusion, which concomitantly promotes transport of autophagic and endocytic cargo to the degradative compartments.
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TL;DR: In this article, the silicon pixel tracking system for the ATLAS experiment at the Large Hadron Collider is described and the performance requirements are summarized and detailed descriptions of the pixel detector electronics and the silicon sensors are given.
Abstract: The silicon pixel tracking system for the ATLAS experiment at the Large Hadron Collider is described and the performance requirements are summarized. Detailed descriptions of the pixel detector electronics and the silicon sensors are given. The design, fabrication, assembly and performance of the pixel detector modules are presented. Data obtained from test beams as well as studies using cosmic rays are also discussed.
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TL;DR: Erythropoiesis-stimulating agent administration to patients with cancer is associated with increased risks of venous thromboembolism (VTE) and mortality, and these findings raise concern about the safety of ESA administration to Patients with cancer.
Abstract: Context The erythropoiesis-stimulating agents (ESAs) erythropoietin and darbepoetin are licensed to treat chemotherapy-associated anemia in patients with nonmyeloid malignancies. Although systematic overviews of trials have identified venous thromboembolism (VTE) risks, none have identified mortality risks with ESAs. Objective To evaluate VTE and mortality rates associated with ESA administration for the treatment of anemia among patients with cancer. Data Sources A published overview from the Cochrane Collaboration (search dates: January 1, 1985-April 1, 2005) and MEDLINE and EMBASE databases (key words: clinical trial, erythropoietin, darbepoetin, and oncology), the public Web site of the US Food and Drug Administration and ESA manufacturers, and safety advisories (search dates: April 1, 2005-January 17, 2008). Study Selection Phase 3 trials comparing ESAs with placebo or standard of care for the treatment of anemia among patients with cancer. Data Extraction Mortality rates, VTE rates, and 95% confidence intervals (CIs)
were extracted by 3 reviewers from 51 clinical trials with 13 611
patients that included survival information and 38 clinical trials with 8172 patients that included information on VTE. Data Synthesis Patients with cancer who received ESAs had increased VTE risks (334 VTE events among 4610 patients treated with ESA vs 173 VTE events among 3562 control patients; 7.5% vs 4.9%; relative risk, 1.57; 95%
CI, 1.31-1.87) and increased mortality risks (hazard ratio, 1.10;
95% CI, 1.01-1.20). Conclusions Erythropoiesis-stimulating agent administration to patients with cancer is associated with increased risks of VTE and mortality.
Our findings, in conjunction with basic science studies on erythropoietin and erythropoietin receptors in solid cancers, raise concern about the safety of ESA administration to patients with cancer.
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TL;DR: Day-29 marrow MRD was the most important prognostic variable in multi-variate analysis and associated with shorter event-free survival (EFS) in all risk groups; even patients with 0.1% day-29 MRD had poor outcome compared with patients negative for MRD patients.
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TL;DR: It is shown that autophagy is controlled by recognizing conserved pathogen‐associated molecular patterns (PAMPs) and that the newly recognized ability of TLR ligands to stimulate Autophagy can be used to treat intracellular pathogens.
Abstract: Autophagy is a newly recognized innate defense mechanism, acting as a cell-autonomous system for elimination of intracellular pathogens. The signals and signalling pathways inducing autophagy in response to pathogen invasion are presently not known. Here we show that autophagy is controlled by recognizing conserved pathogen-associated molecular patterns (PAMPs). We screened a PAMP library for effects on autophagy in RAW 264.7 macrophages and found that several prototype Toll-like receptor (TLR) ligands induced autophagy. Single-stranded RNA and TLR7 generated the most potent effects. Induction of autophagy via TLR7 depended on MyD88 expression. Stimulation of autophagy with TLR7 ligands was functional in eliminating intracellular microbes, even when the target pathogen was normally not associated with TLR7 signalling. These findings link two innate immunity defense systems, TLR signalling and autophagy, provide a potential molecular mechanism for induction of autophagy in response to pathogen invasion, and show that the newly recognized ability of TLR ligands to stimulate autophagy can be used to treat intracellular pathogens.
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TL;DR: The energy spectrum of cosmic rays above 2.5 x 10;{18} eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described and the hypothesis of a single power law is rejected with a significance greater than 6 standard deviations.
Abstract: The energy spectrum of cosmic rays above 2.5 x 10;{18} eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index gamma of the particle flux, J proportional, variantE;{-gamma}, at energies between 4 x 10;{18} eV and 4 x 10;{19} eV is 2.69+/-0.02(stat)+/-0.06(syst), steepening to 4.2+/-0.4(stat)+/-0.06(syst) at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz'min.
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TL;DR: The latitudinal gradient in marine bacteria supports the hypothesis that the kinetics of metabolism, setting the pace for life, has strong influence on diversity.
Abstract: For two centuries, biologists have documented a gradient of animal and plant biodiversity from the tropics to the poles but have been unable to agree whether it is controlled primarily by productivity, temperature, or historical factors. Recent reports that find latitudinal diversity gradients to be reduced or absent in some unicellular organisms and attribute this to their high abundance and dispersal capabilities would suggest that bacteria, the smallest and most abundant organisms, should exhibit no latitudinal pattern of diversity. We used amplified ribosomal intergenic spacer analysis (ARISA) whole-assemblage genetic fingerprinting to quantify species richness in 103 near-surface samples of marine bacterial plankton, taken from tropical to polar in both hemispheres. We found a significant latitudinal gradient in richness. The data can help to evaluate hypotheses about the cause of the gradient. The correlations of richness with latitude and temperature were similarly strong, whereas correlations with parameters relating to productivity (chlorophyll, annual primary productivity, bacterial abundance) and other variables (salinity and distance to shore) were much weaker. Despite the high abundance and potentially high dispersal of bacteria, they exhibit geographic patterns of species diversity that are similar to those seen in other organisms. The latitudinal gradient in marine bacteria supports the hypothesis that the kinetics of metabolism, setting the pace for life, has strong influence on diversity.
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TL;DR: In this paper, the authors reviewed the available literature on positive airway pressure (PAP) titration for sleep related breathing disorders (SRBDs), including obstructive sleep apnea (OSA).
Abstract: Positive airway pressure (PAP) devices are used to treat patients with sleep related breathing disorders (SRBDs), including obstructive sleep apnea (OSA). After a patient is diagnosed with OSA, the current standard of practice involves performing attended polysomnography (PSG), during which positive airway pressure is adjusted throughout the recording period to determine the optimal pressure for maintaining upper airway patency. Continuous positive airway pressure (CPAP) and bilevel positive airway pressure (BPAP) represent the two forms of PAP that are manually titrated during PSG to determine the single fixed pressure of CPAP or the fixed inspiratory and expiratory positive airway pressures (IPAP and EPAP, respectively) of BPAP for subsequent nightly usage. A PAP Titration Task Force of the American Academy of Sleep Medicine reviewed the available literature. Based on this review, the Task Force developed these recommendations for conducting CPAP and BPAP titrations. Major recommendations are as follows: (1) All potential PAP titration candidates should receive adequate PAP education, hands-on demonstration, careful mask fitting, and acclimatization prior to titration. (2) CPAP (IPAP and/or EPAP for patients on BPAP) should be increased until the following obstructive respiratory events are eliminated (no specific order) or the recommended maximum CPAP (IPAP for patients on BPAP) is reached: apneas, hypopneas, respiratory effort-related arousals (RERAs), and snoring. (3) The recommended minimum starting CPAP should be 4 cm H2O for pediatric and adult patients, and the recommended minimum starting IPAP and EPAP should be 8 cm H2O and 4 cm H2O, respectively, for pediatric and adult patients on BPAP. (4) The recommended maximum CPAP should be 15 cm H2O (or recommended maximum IPAP of 20 cm H2O if on BPAP) for patients or = 12 years. (5) The recommended minimum IPAP-EPAP differential is 4 cm H2O and the recommended maximum IPAP-EPAP differential is 10 cm H2O (6) CPAP (IPAP and/or EPAP for patients on BPAP depending on the type of event) should be increased by at least 1 cm H2O with an interval no shorter than 5 min, with the goal of eliminating obstructive respiratory events. (7) CPAP (IPAP and EPAP for patients on BPAP) should be increased from any CPAP (or IPAP) level if at least 1 obstructive apnea is observed for patients or = 12 years. (8) CPAP (IPAP for patients on BPAP) should be increased from any CPAP (or IPAP) level if at least 1 hypopnea is observed for patients or = 12 years. (9) CPAP (IPAP for patients on BPAP) should be increased from any CPAP (or IPAP) level if at least 3 RERAs are observed for patients or = 12 years. (10) CPAP (IPAP for patients on BPAP) may be increased from any CPAP (or IPAP) level if at least 1 min of loud or unambiguous snoring is observed for patients or = 12 years. (11) The titration algorithm for split-night CPAP or BPAP titration studies should be identical to that of full-night CPAP or BPAP titration studies, respectively. (12) If the patient is uncomfortable or intolerant of high pressures on CPAP, the patient may be tried on BPAP. If there are continued obstructive respiratory events at 15 cm H2O of CPAP during the titration study, the patient may be switched to BPAP. (13) The pressure of CPAP or BPAP selected for patient use following the titration study should reflect control of the patient's obstructive respiration by a low (preferably 3 hr).
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TL;DR: An overview of the evidence for the cellular and physiological actions of GPR30 in estrogen-dependent processes and the relationship of G PR30 with classical estrogen receptors is provided.
Abstract: Steroids play an important role in the regulation of normal physiology and the treatment of disease. Steroid receptors have classically been described as ligand-activated transcription factors mediating long-term genomic effects in hormonally regulated tissues. It is now clear that steroids also mediate rapid signaling events traditionally associated with growth factor receptors and G protein–coupled receptors. Although evidence suggests that the classical steroid receptors are capable of mediating many of these events, more recent discoveries reveal the existence of transmembrane receptors capable of responding to steroids with cellular activation. One such receptor, GPR30, is a member of the G protein–coupled receptor superfamily and mediates estrogen-dependent kinase activation as well as transcriptional responses. In this review, we provide an overview of the evidence for the cellular and physiological actions of GPR30 in estrogen-dependent processes and discuss the relationship of GPR30 with classica...
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TL;DR: The examples provided neatly demonstrate that chiral ureas and thioureas, diols, and phosphoric acids display effective and unique activation modes of catalysis for a broad spectrum of asymmetric organic transformations, including single-step and multiple-step cascade reactions.
Abstract: The utilization of hydrogen bonding as an activation force has become a powerful tool in asymmetric organocatalysis. Significant advances have been made in the recent past in this emerging field. Due to space constraints, this Focus Review summarizes only the key aspects with an emphasis on catalysis based on chiral ureas and thioureas, diols, and phosphoric acids. The examples provided neatly demonstrate that chiral ureas and thioureas, diols, and phosphoric acids display effective and unique activation modes of catalysis for a broad spectrum of asymmetric organic transformations, including single-step and multiple-step cascade reactions. These functionalities, which have the ability to afford efficient H-bond activation of electrophiles including C=O, C=N, aziridines, and epoxides, have established their status as "privileged" functional groups in the design of organocatalysts.
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30 Jan 2008••
TL;DR: In this article, the authors discuss aspects of, and controversies concerning, prenatal weight gain and specific nutrients, and special patient groups who may benefit from intervention by a registered dietitian.
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TL;DR: These findings provide insights into the brain network dynamics preceding human performance errors and suggest that monitoring of the identified precursor states may help in avoiding human errors in critical real-world situations.
Abstract: Humans engaged in monotonous tasks are susceptible to occasional errors that may lead to serious consequences, but little is known about brain activity patterns preceding errors. Using functional MRI and applying independent component analysis followed by deconvolution of hemodynamic responses, we studied error preceding brain activity on a trial-by-trial basis. We found a set of brain regions in which the temporal evolution of activation predicted performance errors. These maladaptive brain activity changes started to evolve ≈30 sec before the error. In particular, a coincident decrease of deactivation in default mode regions of the brain, together with a decline of activation in regions associated with maintaining task effort, raised the probability of future errors. Our findings provide insights into the brain network dynamics preceding human performance errors and suggest that monitoring of the identified precursor states may help in avoiding human errors in critical real-world situations.
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TL;DR: These powerful synthetic methodologies serve as efficient approaches to the construction of complex chiral molecular architectures from simple achiral materials in one-pot transformations under mild conditions with high stereocontrol.
Abstract: The utilisation of chiral secondary amines as promoters for asymmetric cascade reactions has been subject of intensive research in asymmetric organocatalysis in the past few years. Key developments in this area are highlighted in this review. As shown, these powerful synthetic methodologies serve as efficient approaches to the construction of complex chiral molecular architectures from simple achiral materials in one-pot transformations under mild conditions with high stereocontrol.
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TL;DR: The results indicated that students developed more positive attitudes toward math learning through five-week computer math gaming, but there was no significant effect of computer gaming on students' cognitive test performance or metacognitive awareness development.
Abstract: Employing mixed-method approach, this case study examined the in situ use of educational computer games in a summer math program to facilitate 4th and 5th graders' cognitive math achievement, metacognitive awareness, and positive attitudes toward math learning. The results indicated that students developed more positive attitudes toward math learning through five-week computer math gaming, but there was no significant effect of computer gaming on students' cognitive test performance or metacognitive awareness development. The in-field observation and students' think-aloud protocol informed that not every computer math drill game would engage children in committed learning. The study findings have highlighted the value of situating learning activities within the game story, making games pleasantly challenging, scaffolding reflections, and designing suitable off-computer activities.
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TL;DR: A family resilience orientation, based on the conviction that all families have inherent strengths and the potential for growth, provides the family nurse with an opportunity to facilitate family protective and recovery factors and to secure extrafamilial resources to help foster resilience.
Abstract: Family resilience is the successful coping of family members under adversity that enables them to flourish with warmth, support, and cohesion. An increasingly important realm of family nursing practice is to identify, enhance, and promote family resiliency. Based on a review of family research and conceptual literature, prominent factors of resilient families include: positive outlook, spirituality, family member accord, flexibility, family communication, financial management, family time, shared recreation, routines and rituals, and support networks. A family resilience orientation, based on the conviction that all families have inherent strengths and the potential for growth, provides the family nurse with an opportunity to facilitate family protective and recovery factors and to secure extrafamilial resources to help foster resilience.
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University College London1, University of Bern2, University of Antioquia3, Cayetano Heredia University4, University of New Mexico5, Universidad Autónoma de la Ciudad de México6, University of California, Berkeley7, University of Costa Rica8, University of California, Los Angeles9, Universidade Federal do Rio Grande do Sul10, Federal University of Paraná11, National University of Jujuy12, University of Chile13, University of Tarapacá14
TL;DR: An analysis of admixture in thirteen Mestizo populations from seven countries in Latin America based on data for 678 autosomal and 29 X-chromosome microsatellites found extensive variation in Native American and European ancestry among populations and individuals and evidence that admixture across Latin America has often involved predominantly European men and both Native and African women.
Abstract: The large and diverse population of Latin America is potentially a powerful resource for elucidating the genetic basis of complex traits through admixture mapping. However, no genome-wide characterization of admixture across Latin America has yet been attempted. Here, we report an analysis of admixture in thirteen Mestizo populations (i.e. in regions of mainly European and Native settlement) from seven countries in Latin America based on data for 678 autosomal and 29 X-chromosome microsatellites. We found extensive variation in Native American and European ancestry (and generally low levels of African ancestry) among populations and individuals, and evidence that admixture across Latin America has often involved predominantly European men and both Native and African women. An admixture analysis allowing for Native American population subdivision revealed a differentiation of the Native American ancestry amongst Mestizos. This observation is consistent with the genetic structure of pre-Columbian populations and with admixture having involved Natives from the area where the Mestizo examined are located. Our findings agree with available information on the demographic history of Latin America and have a number of implications for the design of association studies in population from the region.