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61.
Jan H. Dring Julian Schrter Jerome Jüngling Saskia Biskup Kerstin A. Klotz Thomas Bast Tobias Dietel G. Christoph Korenke Sophie Christoph Heiko Brennenstuhl Guido Rubboli Rikke S. Mller Gaetan Lesca Yves Chaix Stefan Klker Georg F. Hoffmann Johannes R. Lemke Steffen Syrbe 《International journal of molecular sciences》2021,22(6)
Pathogenic variants in KCNA2, encoding for the voltage-gated potassium channel Kv1.2, have been identified as the cause for an evolving spectrum of neurological disorders. Affected individuals show early-onset developmental and epileptic encephalopathy, intellectual disability, and movement disorders resulting from cerebellar dysfunction. In addition, individuals with a milder course of epilepsy, complicated hereditary spastic paraplegia, and episodic ataxia have been reported. By analyzing phenotypic, functional, and genetic data from published reports and novel cases, we refine and further delineate phenotypic as well as functional subgroups of KCNA2-associated disorders. Carriers of variants, leading to complex and mixed channel dysfunction that are associated with a gain- and loss-of-potassium conductance, more often show early developmental abnormalities and an earlier onset of epilepsy compared to individuals with variants resulting in loss- or gain-of-function. We describe seven additional individuals harboring three known and the novel KCNA2 variants p.(Pro407Ala) and p.(Tyr417Cys). The location of variants reported here highlights the importance of the proline(405)–valine(406)–proline(407) (PVP) motif in transmembrane domain S6 as a mutational hotspot. A novel case of self-limited infantile seizures suggests a continuous clinical spectrum of KCNA2-related disorders. Our study provides further insights into the clinical spectrum, genotype–phenotype correlation, variability, and predicted functional impact of KCNA2 variants. 相似文献
62.
The smart grid is promoted as one of the key elements in a low-carbon transition in many countries. In Denmark, the dominant framing of the smart grid emphasises the challenge of integrating much more wind power into the electricity system and using electricity for heating (heat pumps) and transport (electric cars). In the process of radically transforming the electricity system, strategic system builders need to align many forces, including consumers, who play an important role in the functioning of such large networked systems. System builders need to explore, for instance, whether and how users can be motivated to be flexible in relation to moving electricity consumption over time. This paper reports on one of the first smart-grid-related projects in Denmark in which consumer aspects have been central and where potentials for flexible electricity consumption have been tested. The aim of the paper is to explore what can be learned from such experiments and which roles they play in the construction of the smart grid. In this context, the concept of the ‘aligned user’ is introduced. 相似文献
63.
Predicting suspended sediment concentration from nephelometric turbidity in organic‐rich waters 下载免费PDF全文
Nephelometric turbidity is an optical index for the side scattering of light caused by fine particles suspended in water. When a mixed composition of suspended inorganic and organic materials, including dissolved organic material, is present, turbidity measurements can be affected by the different optical properties of the organic and inorganic materials present, and different turbidimeters are more or less sensitive to these influences. Two different methods of nephelometric turbidity measurement were assessed (using instruments confirming to two different turbidity standard methods: EPA 180.1 and ISO 7027). We investigated the influence of particulate organic matter and coloured dissolved organic matter on relationships between turbidity and suspended sediment concentration for rivers in diverse Otago catchments, in the South Island of New Zealand. The presence of organic matter and dissolved colour affected turbidity measurement owing to light absorption; however, turbidity measurement following the ISO 7027 standard, which specifies near infrared radiation at wavelengths where organic absorption is very weak, was less affected by organics. As a result, rating equations between suspended sediment and turbidity may be significantly different with ISO 7027 compared with EPA 180.1 methods. 相似文献
64.
Lipids in almonds are present as oil bodies in the nut. These oil bodies are surrounded by a membrane of proteins and phospholipids and are a delivery vehicle of energy in the form of triglycerides, similarly to the more studied bovine milk fat globule membrane. Chemical, physical and microscopic analyses revealed major differences in the composition and structure of almond oil bodies and bovine milk fat globules. The lipids of both natural emulsions differed in degree of unsaturation, chain length, and class. The almond oil body membrane does not contain any cholesterol or sphingomyelin unlike the bovine milk fat globule membrane. Therefore, the phospholipid distribution at the surface of the oil bodies did not present any liquid-ordered domains. The membranes, a monolayer around almond oil bodies and a trilayer around bovine fat globules, may affect the stability of the lipid droplets in a food matrix and the way the lipids are digested. 相似文献
65.
66.
Franois Charollais Sophie Fonquernie Christophe Perrais Marc Perez Olivier Dugne Franois Cellier Grard Harbonnier Marie-Pierre Vitali 《Nuclear Engineering and Design》2006,236(5-6):534-2004
In the framework of the French V/HTR fuel development and qualification program, the Commissariat à l’Energie Atomique (CEA) and AREVA are conducting R&D projects covering the mastering of UO2 coated particle and fuel compact fabrication technology. To fulfill this task, a review of past knowledge, of existing technologies and a preliminary laboratory-scale work program have been conducted with the aim of retrieving the know-how on HTR coated particle and compact manufacture:
- • The different stages of UO2 kernel fabrication GSP process have been reviewed, reproduced and improved.
- • The experimental conditions for the chemical vapor deposition of coatings have been defined on dummy kernels and development of innovative characterization methods has been carried out.
- • Former CERCA compacting process has been reviewed and updated.
- • to recover and validate past knowledge,
- • to produce representative HTR TRISO fuel meeting industrial standards,
- • to permit the optimization of reference fabrication processes for kernels and coatings defined previously at a laboratory-scale and the investigation of alternative and innovative fuel design (UCO kernel, ZrC coating),
- • to test alternative compact process options and
- • to fabricate and characterize fuel required for irradiation and qualification purpose.
68.
Francis Gohin Sophie Loyer Michel Lunven Claire Labry Jean-Marie Froidefond Daniel Delmas Martin Huret Alain Herbland 《Remote sensing of environment》2005,95(1):29-46
In biological modelling of the coastal phytoplankton dynamics, the light attenuation coefficient is often expressed as a function of the concentrations of chlorophyll and mineral suspended particulate matter (SPM). In order to estimate the relationship between these parameters over the continental shelf of the northern Bay of Biscay, a set of in situ data has been gathered for the period 1998-2003 when SeaWiFS imagery is available. These data comprise surface measurements of the concentrations of total SPM, chlorophyll, and irradiance profiles from which is derived the attenuation coefficient of the photosynthetically available radiation, KPAR. The performance of the IFREMER look-up table used to retrieve the chlorophyll concentration from the SeaWiFS radiance is evaluated on this new set of data. The quality of the estimated chlorophyll concentration is assessed from a comparison of the variograms of the in situ and satellite-derived chlorophyll concentrations. Once the chlorophyll concentration is determined, the non living SPM, which is defined as the SPM not related to the dead or alive endogenous phytoplankton, is estimated from the radiance at 555 nm by inverting a semi-analytic model. This method provides realistic estimations of concentrations of chlorophyll and SPM over the continental shelf all over the year. Finally, a relationship, based on non living SPM and chlorophyll, is proposed to estimate KPAR on the continental shelf of the Bay of Biscay. The same formula is applied to non living SPM and chlorophyll concentrations, observed in situ or derived from SeaWiFS radiance. 相似文献
69.
Constraint Programming (CP) offers a rich modeling language of constraints embedding efficient algorithms to handle complex and heterogeneous combinatorial problems. To solve hard combinatorial optimization problems using CP alone or hybrid CP-ILP decomposition methods, costs also have to be taken into account within the propagation process. Optimization constraints, with their cost-based filtering algorithms, aim to apply inference based on optimality rather than feasibility. This paper introduces a new optimization constraint, cost-regular. Its filtering algorithm is based on the computation of shortest and longest paths in a layered directed graph. The support information is also used to guide the search for solutions. We believe this constraint to be particularly useful in modeling and solving Column Generation subproblems and evaluate its behaviour on complex Employee Timetabling Problems through a flexible CP-based column generation approach. Computational results on generated benchmark sets and on a complex real-world instance are given.A preliminary version of this paper appeared as [7]. This research was supported by the Mathematics of Information Technology and Complex Systems (MITACS) Internship program in association with Omega Optimisation Inc. (CA). 相似文献
70.
Tight LP bounds for resource constrained project scheduling 总被引:3,自引:0,他引:3
The best lower bound for the Resource Constrained Project Scheduling Problem is currently based on the resolution of several large Linear Programs (Brucker & Knust, EJOR, 107: 272-288, 1998). In this paper, we show that (1) intensive constraint propagation can be used to tighten the initial formulation of the linear programs and (2) we introduce several sets of valid cutting planes. These improvements allow us to close 16 new instances of the PSPLIB with 60 activities and to improve the best known lower bounds of 64 instances.Correspondence to:Philippe BaptisteThe authors would like to thank Peter Brucker and Sigrid Knust for providing their source code as well as Christian Artigues, Jacques Carlier and Philippe Michelon for enlightening discussions on project scheduling. 相似文献