494 research outputs found
Exercise-induced sweat nitrogen excretion: evaluation of a regional collection method using gauze pads
Summary: The exercise-induced sweat nitrogen excretion was investigated during a 45-minute run at moderate intensity on a treadmill. Sweat was collected with a regional collection technique using gauze pads and compared with the whole-body wash-down (WBW) method. In the regional collection, sweat was sampled from the upper back (UB), lower back (LB), abdomen (AB), and thigh (TH). Additionally, the relation of sweat urea, ammonia, and amino acids was investigated with the regional collection method during a second 45-minute run. Independent of the sweat collection method, a significant and positive correlation was found between sweat rate and the excretion rate of the largest nitrogen fraction urea, suggesting that the sweating response to exercise might be one of the most important factors determining absolute sweat nitrogen losses. The urea nitrogen excretion was nearly 140 mg·h−1 in the second run, representing the largest nitrogen fraction. Ammonia nitrogen and amino acid-derived nitrogen rate were approximately 30 mg·h−1 and 10 mg·h−1, respectively. The comparison of the sampling methods during the first run revealed that the urea nitrogen rate was significantly higher, but the ammonia nitrogen rate significantly lower in the WBW. After summing urea and ammonia nitrogen, no significant difference between the methods was observed anymore, except for UB. It is concluded that the regional collection method using gauze pads is a valuable approach to measure exercise-induced sweat nitrogen losses during moderate running exercis
Blending block copolymer micelles in solution ; obstacles of blending
Amphiphilic block copolymers can assemble into a variety of structures on the nanoscale in selective solvent. The micelle blending protocol offers a simple unique route to reproducibly produce polymer nanostructures. Here we expand this blending protocol to a range of polymer micelle systems and self-assembly routes. We found by exploring a range of variables that the systems must be able to reach global equilibrium at some point for the blending protocol to be successful. Our results demonstrate the kinetics requirements, specifically core block glass transition temperature, Tg, and length of the block limiting the exchange rates, for the blending protocol which can then be applied to a wide range of polymer systems to access this simple protocol for polymer self-assembly
DISTRIBUTIONS ISOTOPIQUES DES PRODUITS DE TRANSFERTS TRÈS INÉLASTIQUES ENTRE IONS LOURDS
On compare les distributions isotopiques expérimentales des produits de transfert très inélastiques obtenus par les réactions 40Ca (284 MeV) + 40Ca et 40Ar (295 MeV) + 232Th
Loss of Pediatric Kidney Grafts During the “High–Risk Age Window”: Insights From Pediatric Liver and Simultaneous Liver–Kidney Recipients
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110551/1/ajt12985.pd
Self-assembly in solution of a reversible comb-shaped supramolecular polymer
We report a single step synthesis of a polyisobutene with a bis-urea moiety
in the middle of the chain. In low polarity solvents, this polymer
self-assembles by hydrogen bonding to form a combshaped polymer with a central
hydrogen bonded backbone and polyisobutene arms. The comb backbone can be
reversibly broken, and consequently, its length can be tuned by changing the
solvent, the concentration or the temperature. Moreover, we have proved that
the bulkiness of the side-chains have a strong influence on both the
self-assembly pattern and the length of the backbone. Finally, the density of
arms can be reduced, by simply mixing with a low molar mass bis-urea
Tuning the aggregation behavior of pH-responsive micelles by copolymerization
YesAmphiphilic diblock copolymers, poly(2-(diethylamino)ethyl methacrylate-co-2-(dimethylamino)ethyl methacrylate)-b-poly(2-(dimethylamino)ethyl methacrylate), P(DEAEMA-co-DMAEMA)-b-PDMAEMA with various amounts of DEAEMA have been synthesized by RAFT polymerization. Their micellization in water has been investigated by scattering measurements over a wide pH range. It appeared that the polymers self-assembled into pH sensitive star like micelles. For a given composition, when the pH is varied the extent of aggregation can be tuned reversibly by orders of magnitude. By varying the copolymer composition in the hydrophobic block, the onset and extent of aggregation were shifted with respect to pH. This class of diblock copolymer offers the possibility to select the range of stimuli-responsiveness that is useful for a given application, which can rarely be achieved with conventional diblock copolymers consisting of homopolymeric blocks.European Science Foundation (ESF), Engineering and Physical Sciences Research Council (EPSRC), BP (Firm), Birmingham Science City, Advantage West Midlands (AWM), European Regional Development Fund (ERDF
Protective role of vitamin B6 (PLP) against DNA damage in Drosophila models of type 2 diabetes
Growing evidence shows that improper intake of vitamin B6 increases cancer risk and several studies indicate that diabetic patients have a higher risk of developing tumors. We previously demonstrated that in Drosophila the deficiency of Pyridoxal 5' phosphate (PLP), the active form of vitamin B6, causes chromosome aberrations (CABs), one of cancer prerequisites, and increases hemolymph glucose content. Starting from these data we asked if it was possible to provide a link between the aforementioned studies. Thus, we tested the effect of low PLP levels on DNA integrity in diabetic cells. To this aim we generated two Drosophila models of type 2 diabetes, the first by impairing insulin signaling and the second by rearing flies in high sugar diet. We showed that glucose treatment induced CABs in diabetic individuals but not in controls. More interestingly, PLP deficiency caused high frequencies of CABs in both diabetic models demonstrating that hyperglycemia, combined to reduced PLP level, impairs DNA integrity. PLP-depleted diabetic cells accumulated Advanced Glycation End products (AGEs) that largely contribute to CABs as α-lipoic acid, an AGE inhibitor, rescued not only AGEs but also CABs. These data, extrapolated to humans, indicate that low PLP levels, impacting on DNA integrity, may be considered one of the possible links between diabetes and cancer
Pediatric transplantation
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75084/1/j.1600-6143.3.s4.6.x.pd
Guías para aplicación de Normas de Calidad para los procesos de Ingeniería de Software en productos desarrollados con Lenguajes de Programación Open Source: relevamiento y aplicación en PYMES de la zona de influencia de la UNER Concordia
El Software Libre u Open Source es una forma de licenciamiento que da a los usuarios la libertad de compartir, estudiar y modificar el software. Este paradigma ha tenido impedimentos para su adopción en ambientes empresariales y comerciales debido a concepciones en muchos casos erróneas. En la actualidad, varias de estas ideas se han desmitificado, brindando una dosis de realidad a las oportunidades y obstáculos de esta filosofía. Esto se manifiesta en una evolución y aceptación paulatina de la adopción de software libre como temática central en la Ingeniería de Software.
Este contexto plantea la necesidad de contar con estándares de medición y certificación de calidad específicos para productos de Software Libre y de las competencias y desempeño de empresas y profesionales que utilicen, generen y promocionen el Software Libre. Este proyecto de investigación propuso la formulación de marcos metodológicos y modelos de certificación relacionados con software libre y lenguajes de programación open source, tanto para empresas usuarias como desarrolladoras. De esta manera, se pretendió dar valor agregado y ventaja competitiva a las empresas y profesionales que utilicen, desarrollen y/o promuevan el Software Libre y las tecnologías abiertas
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