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Development of Caenorhabditis elegans pharynx,with emphasis on its nervous system

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Acta Pharmacologica Sinica 2005年第4期26卷 396-404页

作者： marc PILON Catarina M RCK Lundberg Laboratory Chalmers University G teborg S-405 30 Sweden Lundberg Laboratory Chalmers University G teborg S-405 30 Sweden

The Caenorhabditis elegans pharynx is a neuromuscular tube of which the func-tion is to pump and crush bacteria,and inject them into the *** 80-cellpharynx develops via the morphogenesis and differentiation of the ceils that com-pose its semi-spherical primordiurn,and requires the activity of several evolution-arily conserved genes,such as pha-4 (the homolog to the Drosophilaforkheadand vertebrate FoxA),ceh-22 (the homolog to the Drosophila tinman and verte-brate Nkx2.5),and pha-2 (the homolog to the vertebrate Hex).There are 20 neu-rons in the pharynx,each with a reproducible unique *** analysis of axon guidance in the pharynx indicates that some axon trajec-tories are in part established without growth cones,whereas other parts necessi-tate growth cone function and *** we provide an overview of thedevelopmental genetics of the Caenorhabditis elegans pharynx,with an empha-sis on its nervous system.

关键词： Caenorhabditis elegans pharynx axon growth cones morphogenesis heart

Delineating the respective impacts of stochastic curl- and grad-forces in a family of idealized core genetic commitment circuits

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Frontiers of Electrical and Electronic Engineering in China 2016年第2期4卷 69-83页

作者： marc Turcotte Department of Mathematics The University of Texas at Arlington Arlington TX 76109 USA Biological Sciences The University of Texas at Dallas Richardson TX-75080 USA

Stochastic dynamics pervades gene regulation. Despite being random, the dynamics displays a kind of innate structure. In fact, two stochastic forces combine driving efforts： one force originates from the gradient of the underlying stochastic potential, and the other originates from the mathematical curl of the probability flux. The curl force gives rise to rotation. The gradient force gives rise to drift. Together they give rise to helical behavior. Here, it is shown that around and about the vicinity of attractive fixed points, the gradient force naturally wanes but the curl force is found to remain high. This leads to a locally noticeably different type of stochastic track near and about attractive fixed points, compared to tracks in regions where drift dominates. The consistency of this observation with the experimental fact that, in biology, fate commitment appears to not be a-priory locked-in, but rather necessitating active maintenance, is discussed. Hence attractive fixed-points are not only fuzzy, but may effectively be, locally, ＂more free＂.

关键词： systems biology theoretical biology gene regulation nonlinear dynamics stochasticity

Joint Loading Estimation Method for Horse Forelimb High Jerk Locomotion:Jumping

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Journal of Bionic Engineering 2019年第4期16卷 674-685页

作者： Joanne Becker Mermoz Emmanuel Linares Jean-marc Airbus Helicopters Aeroport de Marseille ProvenceMarignane 13700France Aix Marseille Univ CNRSISMInst Movement SciMarseille 13009France

Maximal local loads in animal joints are necessary to design bio-inspired mechanical *** studies presented methods to determine joint reaction forces in humans and ***,many of these methods are invasive,and no work has been published yet about the joint reaction forces in the horse forelimb during ***-invasive methods to measure the kinematics and ground reaction force of a horse forelimb were used in this work.A musculoskeletal model of horse forelimb was built with mechanical methods for the estimation of joint reaction *** entire forelimb was reconstructed by scanning real bones geometry with a 3D optical scanner and modeling all the muscles on a Computer Assisted Design(CAD)*** model dynamics were simulated with OpenSim in order to estimate the joint *** study allows knowing an order of magnitude of the loads at the joints at jumping in order to determine latter the maximal joint contact loading values that will be a key at designing bio-inspired joints for mechanical assemblies.

关键词： joint loading jumping kinematics modelling OpenSim

Phase coexistence properties of liquid mercury:a simulation study

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Rare Metals 2006年第5期25卷 567-571页

作者： Jean-Louis Bretonnet Jean-marc Bomont Laboratoire de Physique des Milieux Denses Université Paul Verlaine1bd F.D.Arago57078 MetzCedex 3France

The thermophysical properties of expanded liquid mercury have been investigated along the liquid-vapor coexistence curve by using Monte Carlo and Molecular Dynamic simulations. For the purpose, an empirical state dependent interatomic potential for the region of dense metallic liquid is used, while the state dependence is not necessary near the cliffcal point. In order to test the validity of this potential, we determine the surface layering and the sound velocity, two properties very sensitive to the choice of the potential. Our results are in quite good agreement with other theoretical results and to the experimental data available in the literature.

关键词： mercury simulation phase coexistence liquid state

Growth and Photosynthesis Responses of a Super Dwarf Rice Genotype to Shade and Nitrogen Supply

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Rice science 2021年第2期28卷 178-190页

作者： marc SCHMIERER Oliver KNOPF Folkard ASCH Institute of Agricultural Sciences in the Tropics University of HohenheimStuttgart 70599Germany Institute for Bio-and Geo-Sciences IBG-2:Plant SciencesForschungszentrum Jülich GmbHJülich 52428Germany

Specific aspects of plant cultivation require tests under fully controlled environmentalconditions with restricted energy supply, such as orbit-based space laboratories and low-light *** these growing conditions, super dwarf plants have been developed as model crops, and a gibberellindeficientSuper Dwarf Rice genotype was proposed as a model crop for space flight plant *** tested this genotype in a climate chamber experiment under different illumination and nitrogen supplylevels to assess its suitability under scenarios with limited resource availability. A 25% reduction inillumination led to a 75% reduction in yield, mainly due to a 60% reduction in formed tillers and 20%reduction in grain weight, and a 80% reduction in illumination caused total yield loss. Leaf area underreduced illumination was significantly lower, and only marginal changes in the dimensions of leaves wereobserved. Plant photosynthesis was not significantly different between control and 75% illumination. Thiswas explained by a higher photochemical efficiency under lower light conditions and a reduced mesophyllresistance. Therefore, we concluded that this genotype is well-suited for plant experiments under spaceand light-limited conditions since it kept its small stature and showed no shade avoidance mechanisms,such as leaf elongation, which would complicate experiments under low-light conditions. Nitrogenconcentrations of 2.8 and 1.4 mmol/L led to no differences in plant growth. We concluded that a nitrogenconcentration of 1.4 mmol/L is sufficient for this genotype under the light intensities.

关键词： super dwarf rice photosynthetic limitation analysis shade nitrogen

The role of L-arginine metabolism in neurocritical care patients

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Neural Regeneration Research 2022年第7期17卷 1446-1453页

作者： Marius marc-Daniel Mader Patrick Czorlich Department of Neurosurgery University Medical Center Hamburg-EppendorfHamburgGermany Institute for Stem Cell Biology and Regenerative Medicine Stanford University School of MedicineStanfordCAUSA

Nitric oxide is an important mediator of vascular autoregulation and is involved in pathophysiological changes after acute neurological *** oxide is generated by nitric oxide synthases from the amino acid L-arginine.L-arginine can also serve as a substrate for arginases or lead to the generation of dimethylarginines,asymmetric dimethylarginine,and symmetric dimethylarginine,by *** dimethylarginine is an endogenous inhibitor of nitric oxide synthase and can lead to endothelial *** review discusses the role of L-arginine metabolism in patients suffering from acute and critical neurological disorders often requiring neuro-intensive care *** addressed in this review include intracerebral hemorrhage,aneurysmal subarachnoid hemorrhage,and traumatic brain *** therapeutic advances in the field are described including current randomized controlled trials for traumatic brain injuries and hemorrhagic stroke.

关键词： arginine brain injuries,traumatic cerebral hemorrhage dimethylarginine nitric oxide stroke subarachnoid hemorrhage

Carbide derived carbon electrode with natural graphite addition in magnesium electrolyte based cell for supercapacitor enhancements

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Journal of Energy Chemistry 2015年第3期24卷 264-270页

作者： Ramasamy Chandrasekaran Jesús Palma marc Anderson Electrochemical Processes Unit Instituto IMDEA Energ?a3 Avda.Ramón de la SagraParque Tecnologico de Móstoles

Herein,we have presented a supercapacitor based on carbide derived carbon（CDC） electrode with natural graphite（NG） *** capacitor was analyzed at 22°C by cyclic voltammetry,galvanostatic charge-discharge and impedance techniques using a 0.5 mol/L of magnesium（II）bis（trifluoro methanesulfonyl） imide（Mg TFSI） in ethylene carbonate-propylene carbonate（EC ：PC = 1 ：1,v/v） as *** results conclude that the CDC cell enhancements have been proven by the composite electrode（5%–30% NG to CDC） especially on the cell efficiency and voltage i.e.,the CDC cell around 2.5 V limit was *** obtainable specific capacitance,real power and energy density are 15 F g-1,1.2 k W kg-1and 15 Wh kg-1,respectively.

关键词： supercapacitor carbide derived carbon magnesium imide organic electrolyte natural graphite

Preventing physician quality of life from impinging on patient quality of care: Weakening the weekend effect

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World Journal of Gastroenterology 2007年第27期13卷 3667-3670页

作者： marc D Basson Department of Surgery John D Dingell VA Medical Center and Wayne State University Detroit Michigan United States

Imprecise or delayed care can reflect many factors, including straightforward difficulties in physician judgment and false negative tests. However, the movement toward decreasing physician work hours also leads to delays in care caused by inadequate staffing or inadequate communication between staffing, which must be addressed if quality of care is to remain high. The demonstration of delays in the management of anastomotic leaks over weekends or in association with false positive radiologic studies exemplifies this challenge.

关键词： Anastomosis Communication Contrast Delay Hand-off Intestine Staffing Weekend

Cachexia and pancreatic cancer: Are there treatment options?

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World Journal of Gastroenterology 2014年第28期20卷 9361-9373页

作者： Tara C Mueller marc A Burmeister Jeannine Bachmann marc E Martignoni Department of Surgery University Hospital Rechts der IsarTechnical University of Munich Braun Melsungen AG/Department of Anesthesiology University Hospital Hamburg Eppendorf

Cachexia is frequently described in patients with pancreatic ductal adenocarcinoma (PDAC) and is associated with reduced survival and quality of life. Unfortunately, the therapeutic options of this multi-factorial and complex syndrome are limited. This is due to the fact that, despite extensive preclinical and clinical research, the underlying pathological mechanisms leading to PDAC-associated cachexia are still not fully understood. Furthermore, there is still a lack of consensus on the definition of cachexia, which complicates the standardization of diagnosis and treatment as well as the analysis of the current literature. In order to provide an efficient therapy for cachexia, an early and reliable diagnosis and consistent monitoring is required, which can be challenging especially in obese patients. Although many substances have been tested in clinical and preclinical settings, so far none of them have been proven to have a long-term effect in ameliorating cancer-associated cachexia. However, recent studies have demonstrated that multidimensional therapeutic modalities are able to alleviate pancreatic cancer-associated cachexia and ultimately improve patients’ outcome. In this current review, we propose a stepwise and pragmatic approach to facilitate and standardize the treatment of cachexia in pancreatic cancer patients. This strategy consists of nutritional, dietary, pharmacological, physical and psychological methods.

关键词： Cachexia Pancreatic neoplasms Nutritional support Gastrointestinal neoplasms