Anabranching and maximum flow efficiency in Magela Creek, northern Australia

Anabranching is the prevailing river pattern found along alluvial tracts of the world's largest rivers. Hydraulic geometry and bed material discharge are compared between single channel and anabranching reaches up to 4 times bank-full discharge in Magela Creek, northern Australia. The anabranching channels exhibit greater sediment transporting capacity per unit available stream power, i.e., maximum flow efficiency (MFE). Simple flume experiments corroborate our field results showing the flow efficiency gains associated with anabranching, and highlight the prospect of a dominant anabranch, which is found in many anabranching rivers. These results demonstrate that anabranching can constitute a stable river pattern in dynamic equilibrium under circumstances in which a continuous single channel would be unable to maintain sediment conveyance. We propose the existence of a flow efficiency continuum that embraces dynamic equilibrium and disequilibrium (vertically accreting) anabranching rivers

The cell adhesion molecule Tag1, transmembrane protein Stbm/Vangl2, and Lamininα1 exhibit genetic interactions during migration of facial branchiomotor neurons in zebrafish

AbstractInteractions between a neuron and its environment play a major role in neuronal migration. We show here that the cell adhesion molecule Transient Axonal Glycoprotein (Tag1) is necessary for the migration of the facial branchiomotor neurons (FBMNs) in the zebrafish hindbrain. In tag1 morphant embryos, FBMN migration is specifically blocked, with no effect on organization or patterning of other hindbrain neurons. Furthermore, using suboptimal morpholino doses and genetic mutants, we found that tag1, lamininα1 (lama1) and stbm, which encodes a transmembrane protein Vangl2, exhibit pairwise genetic interactions for FBMN migration. Using time-lapse analyses, we found that FBMNs are affected similarly in all three single morphant embryos, with an inability to extend protrusions in a specific direction, and resulting in the failure of caudal migration. These data suggest that tag1, lama1 and vangl2 participate in a common mechanism that integrates signaling between the FBMN and its environment to regulate migration

A Cyfip2-Dependent Excitatory Interneuron Pathway Establishes the Innate Startle Threshold

\u27\u27This project was a collaboration with labs at the University of Pennsylvania, North Carolina State University, University of Wisconsin at Madison, and Albert Einstein College of Medicine, and featured senior thesis work by Haverford Biology alum Ben Miltenberg \u2717.\u27\u27 -- author-supplied abstract

Carbon nanotube-based quantum pump in the presence of superconducting lead

Parametric electron pump through superconductor-carbon-nanotube based molecular devices was investigated. It is found that a dc current, which is assisted by resonant Andreev reflection, can be pumped out from such molecular device by a cyclic variation of two gate voltages near the nanotube. The pumped current can be either positive or negative under different system parameters. Due to the Andreev reflection, the pumped current has the double peak structure around the resonant point. The ratio of pumped current of N-SWNT-S system to that of N-SWNT-N system (I^{NS}/I^N) is found to approach four in the weak pumping regime near the resonance when there is exactly one resonant level at Fermi energy inside the energy gap. Numerical results confirm that in the weak pumping regime the pumped current is proportional to the square of the pumping amplitude V_p, but in the strong pumping regime the pumped current has the linear relation with V_p. Our numerical results also predict that pumped current can be obtained more easily by using zigzag tube than by using armchair tube

Association between Inflammation and Cardiac Geometry in Chronic Kidney Disease: Findings from the CRIC Study.

Background Left ventricular hypertrophy (LVH) and myocardial contractile dysfunction are independent predictors of mortality in patients with chronic kidney disease (CKD). The association between inflammatory biomarkers and cardiac geometry has not yet been studied in a large cohort of CKD patients with a wide range of kidney function. Methods Plasma levels of interleukin (IL)-1β, IL-1 receptor antagonist (IL-1RA), IL-6, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β, high-sensitivity C-Reactive protein (hs-CRP), fibrinogen and serum albumin were measured in 3,939 Chronic Renal Insufficiency Cohort study participants. Echocardiography was performed according to the recommendations of the American Society of Echocardiography and interpreted at a centralized core laboratory. Results LVH, systolic dysfunction and diastolic dysfunction were present in 52.3%, 11.8% and 76.3% of the study subjects, respectively. In logistic regression analysis adjusted for age, sex, race/ethnicity, diabetic status, current smoking status, systolic blood pressure, urinary albumin- creatinine ratio and estimated glomerular filtration rate, hs-CRP (OR 1.26 [95% CI 1.16, 1.37], p Conclusion In patients with CKD, elevated plasma levels of hs-CRP and IL-6 are associated with LVH and systolic dysfunction

Quantitative cross-species extrapolation between humans and fish: The case of the anti-depressant fluoxetine

This article has been made available through the Brunel Open Access Publishing Fund.Fish are an important model for the pharmacological and toxicological characterization of human pharmaceuticals in drug discovery, drug safety assessment and environmental toxicology. However, do fish respond to pharmaceuticals as humans do? To address this question, we provide a novel quantitative cross-species extrapolation approach (qCSE) based on the hypothesis that similar plasma concentrations of pharmaceuticals cause comparable target-mediated effects in both humans and fish at similar level of biological organization (Read-Across Hypothesis). To validate this hypothesis, the behavioural effects of the anti-depressant drug fluoxetine on the fish model fathead minnow (Pimephales promelas) were used as test case. Fish were exposed for 28 days to a range of measured water concentrations of fluoxetine (0.1, 1.0, 8.0, 16, 32, 64 μg/L) to produce plasma concentrations below, equal and above the range of Human Therapeutic Plasma Concentrations (HTPCs). Fluoxetine and its metabolite, norfluoxetine, were quantified in the plasma of individual fish and linked to behavioural anxiety-related endpoints. The minimum drug plasma concentrations that elicited anxiolytic responses in fish were above the upper value of the HTPC range, whereas no effects were observed at plasma concentrations below the HTPCs. In vivo metabolism of fluoxetine in humans and fish was similar, and displayed bi-phasic concentration-dependent kinetics driven by the auto-inhibitory dynamics and saturation of the enzymes that convert fluoxetine into norfluoxetine. The sensitivity of fish to fluoxetine was not so dissimilar from that of patients affected by general anxiety disorders. These results represent the first direct evidence of measured internal dose response effect of a pharmaceutical in fish, hence validating the Read-Across hypothesis applied to fluoxetine. Overall, this study demonstrates that the qCSE approach, anchored to internal drug concentrations, is a powerful tool to guide the assessment of the sensitivity of fish to pharmaceuticals, and strengthens the translational power of the cross-species extrapolation

Beyond energy efficiency in evaluating sustainable development in planning and the built environment

The EU has set the policy target of reducing energy use by 20% by the year 2020. Therefore, a substantial consumption decrease is needed in the built environment sector. Despite the great energy efficiency improvements in households, recent energy consumption data analyses show that these targets will unlikely be reached. The general aim of this study is to point out the need to define new indicators and evaluation approaches in urban planning and the built environment which are based on the concept of ‘energy subsidiarity', focusing on local renewable resources rather than on current approaches based on energy efficiency. This concept correlates energy consumption with the energy supply from local renewable resources and is here proposed as the new urban planning evaluation approach toward a sustainable built environment. In the paper, the ‘Jevons Paradox' concept and the ‘energy rebound effect' phenomenon are used to demonstrate how current approaches based on energy efficiency, alone, cannot lead to a remarkable reduction of energy consumption. This is also supported by data on European energy consumption and European energy efficiency in the built environment. Finally, a number of well-known European ecological districts (‘eco-districts') are analysed in terms of sustainable energy strategy as well as energy efficiency and energy balance. This study shows that there is a contradiction between the purpose of some of the eco-districts to be low consumption (or low impacts), and the district renewable energy balance. Only a few of the analysed eco-districts are able to cover energy needs by using renewable energy obtained in the surrounding area. In most of the cases, the focus of the districts' activities is on energy efficiency. According to the ‘Jevons Paradox' and ‘energy rebound effect' paradigm, energy efficiency alone will unlikely lead to an effective reduction in resources' consumption. These results point out the need for a radical shift toward the development of new approaches in the assessment and management of the built environment for sustainabilit

Peer expectations about outstanding competencies of men and women medical students

Men and women enrolled in a combined premedical-medical school programme were asked as they began their clinical training to rate their anticipated competence on sixteen criteria relevant to medical practice. Competence dimensions tapped scientific/technical skills, dedication/commitment, and interpersonal skills. Students then were asked to nominate one classmate whom they expected might be‘the best’in each area. Self-ratings revealed few differences among men and women. Peer nominations, however, revealed a preponderance of male nominees in ten competence areas. Women dominated nominations only in the category of sensitivity to patients. Patterns persisted when peer nominations were controlled for students’academic standing and self-ratings on parallel dimensions. The data suggest that medical school peer groups share expectations about competencies of men and women as physicians which are consistent with generalized sex stereotypes and career patterns of men and women physicians.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74843/1/1467-9566.ep11340055.pd

Glycogen Storage Disease Type Ia:Current Management Options, Burden and Unmet Needs

Glycogen storage disease type Ia (GSDIa) is caused by defective glucose-6-phosphatase, a key enzyme in carbohydrate metabolism. Affected individuals cannot release glucose during fasting and accumulate excess glycogen and fat in the liver and kidney, putting them at risk of severe hypoglycaemia and secondary metabolic perturbations. Good glycaemic/metabolic control through strict dietary treatment and regular doses of uncooked cornstarch (UCCS) is essential for preventing hypoglycaemia and long-term complications. Dietary treatment has improved the prognosis for patients with GSDIa; however, the disease itself, its management and monitoring have significant physical, psychological and psychosocial burden on individuals and parents/caregivers. Hypoglycaemia risk persists if a single dose of UCCS is delayed/missed or in cases of gastrointestinal intolerance. UCCS therapy is imprecise, does not treat the cause of disease, may trigger secondary metabolic manifestations and may not prevent long-term complications. We review the importance of and challenges associated with achieving good glycaemic/metabolic control in individuals with GSDIa and how this should be balanced with age-specific psychosocial development towards independence, management of anxiety and preservation of quality of life (QoL). The unmet need for treatment strategies that address the cause of disease, restore glucose homeostasis, reduce the risk of hypoglycaemia/secondary metabolic perturbations and improve QoL is also discussed.</p