Defective pancreatic beta-cell glycolytic signaling in hepatocyte nuclear factor-1alpha-deficient mice

Mutations in the hepatocyte nuclear factor-1alpha (HNF-1alpha) gene cause maturity onset diabetes of the young type 3, a form of type 2 diabetes mellitus. In mice lacking the HNF-1alpha gene, insulin secretion and intracellular calcium ([Ca2+]i) responses were impaired following stimulation with nutrient secretagogues such as glucose and glyceraldehyde but normal with non-nutrient stimuli such as potassium chloride. Patch clamp recordings revealed ATP-sensitive K+ currents (KATP) in beta-cells that were insensitive to suppression by glucose but normally sensitive to ATP. Exposure to mitochondrial substrates suppressed KATP, elevated [Ca2+]i, and corrected the insulin secretion defect. NAD(P)H responses to glucose were substantially reduced, and inhibitors of glycolytic NADH generation reproduced the mutant phenotype in normal islets. Flux of glucose through glycolysis in islets from mutant mice was reduced, as a result of which ATP generation in response to glucose was impaired. We conclude that hepatocyte nuclear factor-1alpha diabetes results from defective beta-cell glycolytic signaling, which is potentially correctable using substrates that bypass the defect.     

Assessing the scholarly impact of health psychology: A citation analysis of articles published from 1993 to 2003.

Objective: We conducted a citation analysis to explore the impact of articles published in Health Psychology and determine whether the journal is fulfilling its stated mission. Design: Six years of articles (N = 408) representing three editorial tenures from 1993–2003 were selected for analysis. Main Outcome Measures: Articles were coded for several dimensions enabling examination of the relationship of article features to subsequent citations rates. Journals citing articles published in Health Psychology were classified into four categories: (1) psychology, (2) medicine, (3) public health and health policy, and (4) other journals. Results: The majority of citations of Health Psychology articles were in psychology journals, followed closely by medical journals. Studies reporting data collected from college students, and discussing the theoretical implications of findings, were more likely to be cited in psychology journals, whereas studies reporting data from clinical populations, and discussing the practice implications of findings, were more likely to be cited in medical journals. Time since publication and page length were both associated with increased citation counts, and review articles were cited more frequently than observational studies. Conclusion: Articles published in Health Psychology have a wide reach, informing psychology, medicine, public health and health policy. Certain characteristics of articles affect their subsequent pattern of citation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Compressed Genotyping

Over the past three decades we have steadily increased our knowledge on the genetic basis of many severe disorders. Nevertheless, there are still great challenges in applying this knowledge routinely in the clinic, mainly due to the relatively tedious and expensive process of genotyping. Since the genetic variations that underlie the disorders are relatively rare in the population, they can be thought of as a sparse signal. Using methods and ideas from compressed sensing and group testing, we have developed a cost-effective genotyping protocol to detect carriers for severe genetic disorders. In particular, we have adapted our scheme to a recently developed class of high throughput DNA sequencing technologies. The mathematical framework presented here has some important distinctions from the 'traditional' compressed sensing and group testing frameworks in order to address biological and technical constraints of our setting.     

An electrical equivalent for barrier anodic films on aluminium

A duplex-film model for barrier anodic films on aluminium is suggested, the lower layer being homogeneous and amorphous and the upper consisting of a dispersion of a crystalline phase in an amorphous matrix. From impedance measurements over a range of frequencies, the dielectric constants of the layers are estimated as 12 and 9 respectively.     

RADE: resource-efficient supervised anomaly detection using decision tree-based ensemble methods

Machine Learning - The capability to perform anomaly detection in a resource-constrained setting, such as an edge device or a loaded server, is of increasing need due to emerging on-premises...     

A kinetic theory of the dilute solutions of3He in superfluid4He. I. Thermodynamics and equations of motion

A semimicroscopic kinetic theory of the dilute solutions of³He in superfluid⁴He is presented. The theory considers only phonon and³He quasiparticle excitations and is therefore applicable at temperatures of up to about 0.6 K. The model underlying the theory utilizes a modified Landau-Pomeranchuck³He energy spectrum and a second-order momentum expansion for the effective³He quasiparticle interaction. In addition, it accounts for the effective phonon-³He quasiparticle interaction, to first order in the phonon momentum, by using a renormalized concentration-dependent sound velocity. The simplicity of the model enables the derivation of both a complete equilibrium theory and a complete set of equations of motion for the solutions. The resulting expressions for the thermodynamic properties and the macroscopic currents appearing in the equations of motion represent a useful parametrization of these quantities in terms of the parameters of the model. It is shown that the macroscopic currents can be written in a form which seems to have a simple physical interpretation. As expected, it is found that at local equilibrium the expressions for the currents reduce correctly to the respective phenomenological expressions.     

Novel stationary-sample atomic force microscope with beam-tracking lens

An atomic force microscope with a stationary sample and a scanning cantilever using an optical lever method is demonstrated for the first time. The cantilever tip is translated to measure surface profiles while a simple lens attached to the cantilever holder guides a focused beam from a fixed collimated diode laser. The imaging capability is demonstrated up to 100*100 mu m/sup 2/.<>