丙型肝炎病毒JFH1 NS5A基因对HC-J4病毒复制和感染性的影响

目的探讨丙型肝炎病毒(Hepatitis C virus,HCV)2a FL-J6JFH NS5A基因置换对1b型HC-J4复制和感染性的影响,为建立HCV 1b细胞模型奠定基础。方法将JFH1 NS5A置换至HC-J4基因组内,构建嵌合全长基因组HC-J4/JFHNS-5A。体外制备野生型HC-J4、嵌合体及FL-J6JFH的RNA转录体,脂质体介导转染Huh-7.5细胞,采用间接免疫荧光法(IFA)检测转染细胞内的蛋白表达,HCV负链RNA特异性RT-PCR法和荧光定量PCR方法(FQ-PCR)检测基因复制情况。转染后不同时间收集转染细胞上清,感染naive Huh-7.5细胞,观察其感染性。结果 IFA未观察到野生型HC-J4和嵌合体转染细胞内HCV蛋白的表达,但在转染后18 d内的各个时间点,均检测到HCV负链RNA,表明嵌合体和野生型HC-J4在转染细胞内呈低水平复制。转染后第9天和12天,FQ-PCR检测表明,嵌合体转染细胞内HCV RNA水平明显高于野生型转染的细胞(P<0.05)。不同时间点转染细胞上清感染naive Huh-7.5细胞后,IFA均未观察到表达HCV蛋白的阳性细胞。结论 JFH1 NS5A蛋白虽然在一定程度上可提高1b型HC-J4株在体外培养细胞中的复制能力,但还不足以产生能够检测到的感染性病毒颗粒。HCV 1b细胞模型的建立尚受其他因素的影响。     

Performance evaluation of a novel personalized ventilation–personalized exhaust system for airborne infection control

In the context of airborne infection control, it is critical that the ventilation system is able to extract the contaminated exhaled air within the shortest possible time. To minimize the spread of contaminated air exhaled by occupants efficiently, a novel personalized ventilation (PV)–personalized exhaust (PE) system has been developed, which aims to exhaust the exhaled air as much as possible from around the infected person (IP). The PV–PE system was studied experimentally for a particular healthcare setting based on a typical consultation room geometry and four different medical consultation positions of an IP and a healthy person (HP). Experiments using two types of tracer gases were conducted to evaluate two types of PE: Top‐PE and Shoulder‐PE under two different background ventilation systems: Mixing Ventilation and Displacement Ventilation. Personalized exposure effectiveness, intake fraction (iF) and exposure reduction (ε) were used as indices to evaluate the PV–PE system. The results show that the combined PV‐PE system for the HP achieves the lowest intake fraction; and the use of PE system for the IP alone shows much better performance than using PV system for the HP alone.     

Eggcrate UV: a whole ceiling upper‐room ultraviolet germicidal irradiation system for air disinfection in occupied rooms

A novel whole ceiling upper‐room ultraviolet germicidal irradiation (UVGI) system [eggcrate ultraviolet (UV)] has been developed that incorporates open‐cell ‘eggcrate’‐suspended ceiling panels and bare UV lamps with a ceiling fan. Upper‐room UVGI is more effective for air disinfection than mechanical ventilation at much lower installation and operating costs. Conventional upper‐room UVGI fixtures employ multiple tightly spaced horizontal louvers to confine UV to the upper‐room. These louvered fixtures protect occupants in the lower‐room from UV‐induced eye and skin irritation, but at a major cost to fixture efficiency. Using a lamp and ballast from a conventional upper‐room UVGI fixture in the eggcrate UV system, the germicidal efficacy was markedly improved even though the UV radiation emitted by the lamp was unchanged. This fundamental change in the application of upper‐room UVGI air disinfection should permit wider, more effective application of UVGI globally to reduce the spread of airborne infection.     

BCLA CLEAR - Contact lens complications

Contact lens-related complications are common, affecting around one third of wearers, although most are mild and easily managed. Contact lenses have well-defined anatomical and physiological effects on the ocular surface and can result in other consequences due to the presence of a biologically active material. A contact lens interacts with the tear film, ocular surface, skin, endogenous and environmental microorganisms, components of care solutions and other antigens which may result in disease specific to contact lens wear, such as metabolic or hypersensitivity disorders. Contact lens wear may also modify the epidemiology or pathophysiology of recognised conditions, such as papillary conjunctivitis or microbial keratitis. Wearers may also present with intercurrent disease, meaning concomitant or pre-existing conditions unrelated to contact lens wear, such as allergic eye disease or blepharitis, which may complicate the diagnosis and management of contact lens-related disease.Complications can be grouped into corneal infection (microbial keratitis), corneal inflammation (sterile keratitis), metabolic conditions (epithelial: microcysts, vacuoles, bullae, tight lens syndrome, epithelial oedema; stromal: superficial and deep neovascularisation, stromal oedema [striae/folds], endothelial: blebs, polymegethism/ pleomorphism), mechanical (corneal abrasion, corneal erosion, lens binding, warpage/refractive error changes; superior epithelial arcuate lesion, mucin balls, conjunctival epithelial flaps, ptosis, discomfort), toxic and allergic disorders (papillary conjunctivitis, solution-induced corneal staining, incomplete neutralisation of peroxide, Limbal Stem Cell Deficiency), tear resurfacing disorders/dry eye (contact lens-induced dry eye, Meibomian gland dysfunction, lid wiper epitheliopathy, lid parallel conjunctival folds, inferior closure stain, 3 and 9 o'clock stain, dellen, dimple veil) or contact lens discomfort. This report summarises the best available evidence for the classification, epidemiology, pathophysiology, management and prevention of contact lens-related complications in addition to presenting strategies for optimising contact lens wear.     

烟草灰霉病侵染条件的研究

烟草灰霉病是黑龙江烟区新发现病害，个别地块已造成严重损失。自１９９０～１９９５年利用田间试验和控制条件接种方法，研究了烟草灰霉病病菌侵染来源和侵染规律，试验发现：①灰霉病菌Ｂｏｔｒｙｔｉｓｃｉｎｅｒｅａ侵染烟株的最适宜温度在１８℃左右，９℃以下或２７℃以上不能发生侵染，该菌发生侵染还必须满足９ｈ以上的湿润时间，１２～２４ｈ持续湿润利于侵染，光照对病菌侵染有抑制作用。②病菌的侵染来源主要是来自烟株病残体产生的分生孢子。③黑龙江烟区有两个侵染高峰，一个在６月中、下旬，另一个在８月中、下旬。这期间低温、多雨侵染率较高。     

婴幼儿先天性巨细胞病毒感染性感觉神经性耳聋的研究进展

先天性巨细胞病毒感染是引起婴幼儿感觉神经性耳聋的重要原因,也是先天性巨细胞病毒感染最常见的后遗症。耳聋的症状可在新生儿期出现,也可在出生后一段时间(通常在1岁左右)出现。对患儿使用安全范围内的抗病毒药物治疗可以改善听力。本文就婴幼儿先天性巨细胞病毒感染性感觉神经性耳聋的研究进展作一综述。     

Lpconvergence of a process identification algorithm

In this paper, we study the phenomena of the epidemic spreading process in small-world networks, where recovery responses are practically delayed. We propose and investigate three novel linear delayed SIR models for different cases of recovery response. Because the recovery strategies respond with some time-delays as happens in practice, it is found that the unsuitable recovery strength may not suppress the prevalent epidemics and even lead to oscillations. Therefore, it is strongly suggested that the administrative authorities should apply control strategies of recovery as soon as possible on the small prevalent viruses before they spread into a disaster of infections.     

An overview of recent applications of Game Theory to bioinformatics

The goal of this work is to provide a comprehensive review of different Game Theory applications that have been recently used to predict the behavior of non-rational agents in interaction situations arising from computational biology.In the first part of the paper, we focus on evolutionary games and their application to modelling the evolution of virulence. Here, the notion of Evolutionary Stable Strategy (ESS) plays an important role in modelling mutation mechanisms, whereas selection mechanisms are explained by means of the concept of replicator dynamics.In the second part, we describe a couple of applications concerning cooperative games in coalitional form, namely microarray games and Multi-perturbation Shapley value Analysis (MSA), for the analysis of genetic data. In both of the approaches, the Shapley value is used to assess the power of genes in complex regulatory pathways.     

电力系统谐波对电能计量的影响

高压大功率电力电子电源容量的不断提高,给电力系统的电量计量带来了诸多问题.在分析电能表计量原理的基础上,对比分析了在谐波情况下电子式与电磁感应式电能表的计量差异,提出基于电力谐波的合理电能计量方法,并进行模拟验证.