Terrestrial ecosystems often vary dramatically in their responses to drought, but the reasons for this are unclear. With climate change forecasts for more frequent and extensive drought in the future, a more complete understanding of the mechanisms that determine differential ecosystem sensitivity to drought is needed. In 2012, the Central US experienced the fourth largest drought in a century, with a regional-scale 40% reduction in growing season precipitation affecting ecosystems ranging from desert grassland to mesic tallgrass prairie.
View Article and Find Full Text PDFBackground: Neonatal sepsis is a major cause of neonatal mortality. In populations with limited access to health care, early identification of bacterial infections and initiation of antibiotics by community health workers (CHWs) could be lifesaving. It is unknown whether this strategy would be feasible using traditional birth attendants (TBAs), a cadre of CHWs who typically have limited training and educational backgrounds.
View Article and Find Full Text PDFA quantitative understanding of sources and sinks of fixed nitrogen in low-oxygen waters is required to explain the role of oxygen-minimum zones (OMZs) in controlling the fixed nitrogen inventory of the global ocean. Apparent imbalances in geochemical nitrogen budgets have spurred numerous studies to measure the contributions of heterotrophic and autotrophic N2-producing metabolisms (denitrification and anaerobic ammonia oxidation, respectively). Recently, 'cryptic' sulphur cycling was proposed as a partial solution to the fundamental biogeochemical problem of closing marine fixed-nitrogen budgets in intensely oxygen-deficient regions.
View Article and Find Full Text PDFCigarette smoking is one of the leading causes of disease and death in the United States, and smoking typically begins in adolescence. It is therefore important to understand factors that relate to increased risk for cigarette smoking during this stage of development. Adolescence is a period when emotion regulatory capacities are still emerging and a common affective state to be regulated is anger, which adult research has linked to nicotine use.
View Article and Find Full Text PDFBackground: Hif1p is an H3/H4-specific histone chaperone that associates with the nuclear form of the Hat1p/Hat2p complex (NuB4 complex) in the yeast Saccharomyces cerevisiae. While not capable of depositing histones onto DNA on its own, Hif1p can act in conjunction with a yeast cytosolic extract to assemble nucleosomes onto a relaxed circular plasmid.
Results: To identify the factor(s) that function with Hif1p to carry out chromatin assembly, multiple steps of column chromatography were carried out to fractionate the yeast cytosolic extract.
Intensification of the global hydrological cycle with atmospheric warming is expected to increase interannual variation in precipitation amount and the frequency of extreme precipitation events. Although studies in grasslands have shown sensitivity of aboveground net primary productivity (ANPP) to both precipitation amount and event size, we lack equivalent knowledge for responses of belowground net primary productivity (BNPP) and NPP. We conducted a 2-year experiment in three US Great Plains grasslands--the C4-dominated shortgrass prairie (SGP; low ANPP) and tallgrass prairie (TGP; high ANPP), and the C3-dominated northern mixed grass prairie (NMP; intermediate ANPP)--to test three predictions: (i) both ANPP and BNPP responses to increased precipitation amount would vary inversely with mean annual precipitation (MAP) and site productivity; (ii) increased numbers of extreme rainfall events during high-rainfall years would affect high and low MAP sites differently; and (iii) responses belowground would mirror those aboveground.
View Article and Find Full Text PDFBackground: Electronic auscultation appears superior to acoustic auscultation for identifying hemodynamic abnormalities. The aim of this study was to determine whether carotid bruits detected by electronic stethoscope in patients with diabetes are associated with stenoses and increased carotid intima-medial thickness (CIMT).
Subjects And Methods: Fifty Fremantle Diabetes Study patients (mean±SD age, 73.
Herbivory and fire shape plant community structure in grass-dominated ecosystems, but these disturbance regimes are being altered around the world. To assess the consequences of such alterations, we excluded large herbivores for seven years from mesic savanna grasslands sites burned at different frequencies in North America (Konza Prairie Biological Station, Kansas, USA) and South Africa (Kruger National Park). We hypothesized that the removal of a single grass-feeding herbivore from Konza would decrease plant community richness and shift community composition due to increased dominance by grasses.
View Article and Find Full Text PDFEscape and avoidance behaviors play a prominent role in the maintenance and possibly development of panic disorder, yet the literature regarding the etiology of these emotion-regulation strategies is relatively underdeveloped. The current study experimentally tests hypotheses that parental modeling of escape during a well-established panic-relevant biological challenge increases panic-relevant escape and avoidance among offspring. Fifty physically and psychologically healthy early adolescents (28 females; Mage=11.
View Article and Find Full Text PDFAs previously shown for imatinib, therapeutic drug monitoring (TDM) of vemurafenib should be important to measure efficacy of the treatment in melanoma patient. A micro-method based on liquid chromatography coupled to triple quadrupole spectrometry detection using only 10μL of plasma was validated. A simple protein precipitation with water/acetonitrile was used after addition of vemurafenib-(13)C6 as internal standard.
View Article and Find Full Text PDFObjective: There have been no studies of the effect of continuous positive airway pressure (CPAP) therapy on erectile dysfunction (ED) and serum testosterone in men with type 2 diabetes and obstructive sleep apnoea (OSA), a patient group at increased risk of ED and hypogonadism. The aim of this study was to determine whether CPAP improves sexual and gonadal function in males with type 2 diabetes and a pre-CPAP apnoea-hypopnoea index >15/h.
Design: Substudy of a trial assessing the effect of 3 months of CPAP on cardiovascular risk in type 2 diabetes.
Tumors with defective mismatch repair acquire large numbers of strand slippage mutations including frameshifts in coding sequence repeats. We identified a mutational hotspot, p.T204fs, in the insulator-binding protein (CTCF) in MSI-positive endometrial cancers.
View Article and Find Full Text PDFMillions of individuals with posttraumatic stress disorder (PTSD) are parents. A burgeoning literature suggests that offspring of parents with this condition may be at increased risk for psychological problems. The current paper provides an integrative and comprehensive review of the diverse research literature examining the sequelae of parental posttraumatic stress among offspring.
View Article and Find Full Text PDFThe expression of apoptosis genes in a commercial pre-designed low-density array from Applied Biosystems was evaluated in two human brain cancer cell models, LN-18 and Daoy (HTB-186™) in comparison to the reference human primary endothelial cells under basic conditions. Analysis of the gene expression in the cancer cell lines compared to the normal control revealed features reflecting anti-apoptotic and inflammatory characteristics of the former. There was an overall downregulation of apoptosis-stimulating genes in both cancer cell lines, along with an upregulation of certain apoptosis inhibitors.
View Article and Find Full Text PDFStroke is a devastating event which can result in permanent disability. Due to the lack of treatments available for use after stroke, compounds which work to limit cell loss, reduce behavioral deficits, and enhance recovery of function are needed. The isoflavone daidzein has been demonstrated to be neuroprotective when fed to rats beginning prior to stroke.
View Article and Find Full Text PDFThe number of bariatric surgical procedures is still increasing in Germany and also worldwide. According to the German quality assurance study of surgical treatment of obesity, the laparoscopic adjustable gastric banding (LAGB) was the most common bariatric operation with a total of 678 cases between 2004 and 2006 in Germany. In the meantime a high rate of LAGB treatment failures has been reported, so that a high rate of revisional bariatric operations is required.
View Article and Find Full Text PDFIndependent lines of evidence have linked posttraumatic stress symptomatology to both peritraumatic disgust (i.e., disgust experienced during a traumatic event) and posttraumatic disgust reactivity in response to traumatic event cues among individuals exposed to traumatic events.
View Article and Find Full Text PDFHAX-1 is a multi-functional protein that is involved in the regulation of apoptosis, cell motility and calcium homeostasis. It is also reported to bind RNA: it associates with structural motifs present in the 3' untranslated regions of at least two transcripts, but the functional significance of this binding remains unknown. Although HAX-1 has been detected in various cellular compartments, it is predominantly cytoplasmic.
View Article and Find Full Text PDFThe mechanisms behind flares of human autoimmune diseases in general, and of systemic lupus in particular, are poorly understood. The present scenario proposes that predisposing gene defects favour clinical flares under the influence of external stimuli. Here, we show that Carabin is low in B cells of (NZB × NZW) F1 mice (murine SLE model) long before the disease onset, and is low in B cells of lupus patients during the inactive phases of the disease.
View Article and Find Full Text PDFFront Microbiol
October 2012
The dominant process adding nitrogen (N) to the ocean, di-nitrogen (N(2)) fixation, is mediated by prokaryotes (diazotrophs) sensitive to a variety of environmental factors. In particular, it is often assumed that consequential rates of marine N(2) fixation do not occur where concentrations of nitrate (NO(-) (3)) and/or ammonium (NH(+) (4)) exceed 1μM because of the additional energetic cost associated with assimilating N(2) gas relative to NO(-) (3) or NH(+) (4). However, an examination of culturing studies and in situ N(2) fixation rate measurements from marine euphotic, mesopelagic, and benthic environments indicates that while elevated concentrations of NO(-) (3) and/or NH(+) (4) can depress N(2) fixation rates, the process can continue at substantial rates in the presence of as much as 30μM NO(-) (3) and/or 200μM NH(+) (4).
View Article and Find Full Text PDFPurpose: Youth with special health care needs (YSHCN) increasingly live into adulthood, and approximately 500,000 U.S. youth transition from pediatric to adult health care systems annually.
View Article and Find Full Text PDFElectrically connected resonant optical antennas hold promise for the realization of highly efficient nanoscale electro-plasmonic devices that rely on a combination of electric fields and local near-field intensity enhancement. Here we demonstrate the feasibility of such a concept by attaching leads to the arms of a two-wire antenna at positions of minimal near-field intensity with negligible influence on the antenna resonance. White-light scattering experiments in accordance with simulations show that the optical tunability of connected antennas is fully retained.
View Article and Find Full Text PDFBackground: The Lufwanyama Neonatal Survival Project ("LUNESP") was a cluster randomized, controlled trial that showed that training traditional birth attendants (TBAs) to perform interventions targeting birth asphyxia, hypothermia, and neonatal sepsis reduced all-cause neonatal mortality by 45%. This companion analysis was undertaken to analyze intervention costs and cost-effectiveness, and factors that might improve cost-effectiveness.
Methods And Findings: We calculated LUNESP's financial and economic costs and the economic cost of implementation for a forecasted ten-year program (2011-2020).