并行工程中的任务组织

利用信息论中的香农熵对信息流进行度量,建立了模糊设计结构矩阵,通过分解和割裂算法对该矩阵进行重构,探讨了串行设计和并行设计过程的收敛性,经过重新组织后的设计过程为并行设计的管理、控制、实施提供了新的策略.     

Rational design of carbon shell-encapsulated cobalt nanospheres to enhance microwave absorption performance

Co@C core–shell nanospheres highly dispersed on carbon supports were rationally designed to improve the microwave absorbing property of the composite material, and fabricated by one pot thermal decomposition and simple annealing process. The Co nanospheres were completely encapsulated with thin carbon shells, which can effectively prevent the oxidation of the Co surface. Additionally, the particle size of Co nanospheres were properly controlled to optimize the electromagnetic property of the composite material. As a result, the lightweight Co@C/C composites with the particle size of 20 nm exhibited much enhanced microwave absorption properties. The improved microwave absorption performance is attributed mainly to the enhanced isotropic ratio and impedance matching of magnetic composites via tuning the Co particle size. Therefore, the welldesigned core-shell Co@C composite structure will provide a new insight for the development of high performance microwave absorbers.     

Tight linkage between a splicing mutation and a specific DNA haplotype in phenylketonuria

The first phenylketonuria mutation identified in the human phenylalanine hydroxylase gene is a single base substitution (GT----AT) in the canonical 5'-splice donor site of intron 12. Direct hybridization analysis using specific oligonucleotide probes demonstrates that the mutation is tightly associated with a specific restriction fragment-length polymorphism haplotype among mutant alleles. The splicing mutation is the most prevalent phenylketonuria allele among Caucasians, and the results suggest the possibility of detecting carriers of the genetic trait who have no family history of phenylketonuria.     

Peristaltic movement of the tortoise intestine

Zusammenfassung Am Schildkrötendarm kann die peristaltische Bewegung weder durch Erhöhung des Binnendruckes, noch durch Kombination interner Applikation von 5-Hydroxytryptamin oder Acetylcholin mit Druck angeregt werden. Druckwirkung auf die Mucosa und Einwirkung von 5-Hydroxytryptamin oder Acetylcholin auf die Serosa war jeweils erfolgreich. Präparate von Längsmuskelstreifen reagierten nicht auf 5-Hydroxytryptamin, während die Ringmuskelstreifen mit Kontraktur antworteten.     

嫦娥五号飞行试验器发射日雷雨天气过程气象保障分析

简要介绍了嫦娥五号飞行试验器发射日对任务进程有重大影响的射前8小时雷雨天气的保障,对该雷雨天气过程的降水、雷暴预报和物理量进行详细分析。结果表明,发射窗口天气预报准确、及时、可靠,为发射任务成功实施提供了重要决策依据,是一次成功的航天气象保障个例,可为后续高密度航天试验任务气象保障提供借鉴。     

Biomimetic synthesis of ordered silica structures mediated by block copolypeptides

In biological systems such as diatoms and sponges, the formation of solid silica structures with precisely controlled morphologies is directed by proteins and polysaccharides and occurs in water at neutral pH and ambient temperature. Laboratory methods, in contrast, have to rely on extreme pH conditions and/or surfactants to induce the condensation of silica precursors into specific morphologies or patterned structures. This contrast in processing conditions and the growing demand for benign synthesis methods that minimize adverse environmental effects have spurred much interest in biomimetic approaches in materials science. The recent demonstration that silicatein-a protein found in the silica spicules of the sponge Tethya aurantia--can hydrolyse and condense the precursor molecule tetraethoxysilane to form silica structures with controlled shapes at ambient conditions seems particularly promising in this context. Here we describe synthetic cysteine-lysine block copolypeptides that mimic the properties of silicatein: the copolypeptides self-assemble into structured aggregates that hydrolyse tetraethoxysilane while simultaneously directing the formation of ordered silica morphologies. We find that oxidation of the cysteine sulphydryl groups, which is known to affect the assembly of the block copolypeptide, allows us to produce different structures: hard silica spheres and well-defined columns of amorphous silica are produced using the fully reduced and the oxidized forms of the copolymer, respectively.     

宁波地铁站规划设计探析

地铁站作为地铁系统上的节点空间,在当代城市中扮演着越来越重要的角色。文章以分析大量的事例与研究为基础,对即将动工的宁波地铁站规划设计提出"以人为本"的人性化设计理念,具体分析城市背景,凸显宁波地域文化。从地铁站与城市、地铁站与人的需求、地铁站与周边环境等几个方面论述宁波地铁站的规划设计方向。对目前宁波地铁站规划设计的发展提供有益的参考与借鉴。     

量子包络代数Uq（sl2）的代数自同构

令Ｕｑ表示一个有限维单李代数ψ的普遍包络代数的量子化。文献「１」描述了代数Ｕｑ（ψ）的所有Ｈｏｐｆ－代数自同构。文献「２」确定Ｕｑ（ψ）的所有变形代数自同构，所谓变形代数自同构是指底下的单李代数ψ的自同构的形变。文中将确定代数Ｕｑ（ｓｌ２）的所有代数自同构。从而表明Ｕｑ（ｓｌ２）的所有代数自同构都是变形代数自同构。     

Atomic scale movement of the voltage-sensing region in a potassium channel measured via spectroscopy

Voltage-gated ion channels are transmembrane proteins that are essential for nerve impulses and regulate ion flow across cell membranes in response to changes in membrane potential. They are made up of four homologous domains or subunits, each of which contains six transmembrane segments. Studies of potassium channels have shown that the second (S2) and fourth (S4) segments contain several charged residues, which sense changes in voltage and form part of the voltage sensor. Although these regions clearly undergo conformational changes in response to voltage, little is known about the nature of these changes because voltage-dependent distance changes have not been measured. Here we use lanthanide-based resonance energy transfer to measure distances between Shaker potassium channel subunits at specific residues. Voltage-dependent distance changes of up to 3.2 A were measured at several sites near the S4 segment. These movements directly correlated with electrical measurements of the voltage sensor, establishing the link between physical changes and electrical charge movement. Measured distance changes suggest that the region associated with the S4 segment undergoes a rotation and possible tilt, rather than a large transmembrane movement, in response to voltage. These results demonstrate the first in situ measurement of atomic scale movement in a trans-membrane protein.