Simplicity in Eulerian circuits: Uniqueness and safety

An Eulerian circuit in a directed graph is one of the most fundamental Graph Theory notions. Detecting if a graph G has a unique Eulerian circuit can be done in polynomial time via the BEST theorem by de Bruijn, van Aardenne-Ehrenfest, Smith and Tutte (1941–1951) [15], [16] (involving counting arborescences), or via a tailored characterization by Pevzner, 1989 (involving computing the intersection graph of simple cycles of G), both of which thus rely on overly complex notions for the simpler uniqueness problem.In this paper we give a new linear-time checkable characterization of directed graphs with a unique Eulerian circuit. This is based on a simple condition of when two edges must appear consecutively in all Eulerian circuits, in terms of cut nodes of the underlying undirected graph of G. As a by-product, we can also compute in linear-time all maximal safe walks appearing in all Eulerian circuits, for which Nagarajan and Pop proposed in 2009 [12] a polynomial-time algorithm based on Pevzner characterization.     

Self-efficacy and academic success among ethnically diverse first-generation community college students.

A longitudinal analysis of self-efficacy for education and sociodemographic characteristics was conducted among an ethnically diverse sample of first-generation college students (FGS) attending an urban community college. Baseline rates of self-efficacy for education and first-generation immigrant status significantly predicted increased cumulative grade point average at 1-year follow-up. These findings suggest that self-efficacy for education is an important cognitive resource among ethnically diverse FGS attending community colleges, whose immigrant generation status might have an impact on their educational success. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The Use of a Mobile Sludge Dewatering Unit at Small Sewage-Treatment Plants in Japan

The construction of small sewage-treatment works in Japan is increasing. In most municipalities, economical and effective treatment/maintenance systems, which match the local conditions, are needed. As one of its support strategies, the Japan Sewage Works Agency has initiated and implemented 'co-operation' projects. In one of these projects, a mobile sludge dewatering unit has been shown to be the most economical method of treatment. The first unit, which was commissioned in March 1992, is being used in three municipalities, and this paper appraises its use.     

Long-Range PCR-Based NGS Applications to Diagnose Mendelian Retinal Diseases

The purpose of this study was to develop a flexible, cost-efficient, next-generation sequencing (NGS) protocol for genetic testing. Long-range polymerase chain reaction (PCR) amplicons of up to 20 kb in size were designed to amplify entire genomic regions for a panel (n = 35) of inherited retinal disease (IRD)-associated loci. Amplicons were pooled and sequenced by NGS. The analysis was applied to 227 probands diagnosed with IRD: (A) 108 previously molecularly diagnosed, (B) 94 without previous genetic testing, and (C) 25 undiagnosed after whole-exome sequencing (WES). The method was validated with 100% sensitivity on cohort A. Long-range PCR-based sequencing revealed likely causative variant(s) in 51% and 24% of proband from cohorts B and C, respectively. Breakpoints of 3 copy number variants (CNVs) could be characterized. Long-range PCR libraries spike-in extended coverage of WES. Read phasing confirmed compound heterozygosity in 5 probands. The proposed sequencing protocol provided deep coverage of the entire gene, including intronic and promoter regions. Our method can be used (i) as a first-tier assay to reduce genetic testing costs, (ii) to elucidate missing heritability cases, (iii) to characterize breakpoints of CNVs at nucleotide resolution, (iv) to extend WES data to non-coding regions by spiking-in long-range PCR libraries, and (v) to help with phasing of candidate variants.     

天作之合“BREITLING for BENTLEY”——“BEST for the BEST”

百年灵此次北京之行，媒体专访安排在赛特的宾利展厅，这个location已是两大“B”品牌之间联系密切，最好而直接的证明。     

1 000 MW机组不同BEST级数下变工况回热特性研究

为了寻找抽汽背压式汽轮机(back pressure extraction steam turbine,BEST)最佳的级数方案,以配置BEST的二次再热机组为设计基础,保持总回热级数不变,BEST级数从4级增加到8级,对比不同BEST级数下机组的可行性、变工况特性及热经济性.结果表明:从BEST功率相对给水泵功率的裕...     

Nothing More than a Fragile Edge: Blurring the Boundaries with Mario Cucinella

The main focus of Mario Cucinella's work is an overlapping preoccupation with technology and the natural environment. In his hands buildings are transformed into complex climatic machines. Anna Giorgi explains how, when combined with an instinctive sense of place, these concerns allow Cucinella's buildings to remain open objects, fragments of a greater natural or urban system. Copyright © 2007 John Wiley & Sons, Ltd.     

四种阻垢剂与Mg2+之间的配位化学作用研究

本文采用酸碱电位滴定分析方法，运用先进的数据处理程序-BEST程序，通过建立恰当的配位化学模式，研究了水溶液中四种阻垢剂：氨基三甲叉磷酸(ATMP)、2-磷基-1，4-丁三酸(PBTCA)、聚丙烯酸(PAA，MW=2000)、马丙共聚物(PMAAA，MW=3000)自身的解离以及与Mg^2 离子间的配位化学作用，得到相应的配合物稳定常数，作出各种配合物在不同pH值下形态分布图，并对阻垢机理的解释提供一定的理论基础。     

Impaired Bestrophin Channel Activity in an iPSC-RPE Model of Best Vitelliform Macular Dystrophy (BVMD) from an Early Onset Patient Carrying the P77S Dominant Mutation

Best Vitelliform Macular dystrophy (BVMD) is the most prevalent of the distinctive retinal dystrophies caused by mutations in the BEST1 gene. This gene, which encodes for a homopentameric calcium-activated ion channel, is crucial for the homeostasis and function of the retinal pigment epithelia (RPE), the cell type responsible for recycling the visual pigments generated by photoreceptor cells. In BVMD patients, mutations in this gene induce functional problems in the RPE cell layer with an accumulation of lipofucsin that evolves into cell death and loss of sight. In this work, we employ iPSC-RPE cells derived from a patient with the p.Pro77Ser dominant mutation to determine the correlation between this variant and the ocular phenotype. To this purpose, gene and protein expression and localization are evaluated in iPSC-RPE cells along with functional assays like phagocytosis and anion channel activity. Our cell model shows no differences in gene expression, protein expression/localization, or phagocytosis capacity, but presents an increased chloride entrance, indicating that the p.Pro77Ser variant might be a gain-of-function mutation. We hypothesize that this variant disturbs the neck region of the BEST1 channel, affecting channel function but maintaining cell homeostasis in the short term. This data shed new light on the different phenotypes of dominant mutations in BEST1, and emphasize the importance of understanding its molecular mechanisms. Furthermore, the data widen the knowledge of this pathology and open the door for a better diagnosis and prognosis of the disease.     

BEST井下开关井工具在渤海油田试井中的应用

BEST井下开关井工具通过钢丝作业的方式将工具串送入井下工作筒内，脱手坐封于工作筒并密封工作筒以下的测试部分，由已编程序控制流体快速关闭阀的启、闭，实现井下开关井的目的。通过现场实验证明，确实达到预期的效果，具有广阔的推广应用前景和较高的使用价值。