Research bronchoscopies do not adversely affect HIV-infected individuals' future health-care decisions

STUDY OBJECTIVES: Asymptomatic HIV-infected individuals are increasingly recruited for studies involving invasive procedures such as bronchoscopy. We sought to determine the response to and outcome of a request for a research bronchoscopy in HIV-positive individuals with no respiratory disease, and whether this would adversely affect future decisions to have a medically indicated bronchoscopy. DESIGN AND SETTING: Prospective, semistructured, questionnaire-based study in a London teaching hospital HIV outpatient clinic. PARTICIPANTS: One hundred and seven consecutive HIV-infected eligible individuals. Thirty-one healthy volunteers served as a control group for the subjective response to bronchoscopy. MAIN OUTCOME MEASURES: Subjects' attitudes and responses to requests for bronchoscopy and subsequent behavior when they required medically indicated bronchoscopy. RESULTS: Seventy-five patients (70%) agreed to the procedure in principle, predominantly for altruistic reasons. Thirty-nine subjects underwent bronchoscopy. Five percent found it worse than expected; and 79% agreed to another research bronchoscopy (performed in 11 subjects approximately 2 years later). All patients said they would undergo bronchoscopy again for diagnostic purposes (required in seven during the study). When compared to a healthy volunteer population within the same study, postbronchoscopy symptoms were similar in frequency although somewhat different in nature. Subjects felt that a clear explanation of what was involved enhanced their participation in this research. CONCLUSIONS: Invasive research procedures such as bronchoscopy can be performed and are repeatable in a healthy HIV-infected population. Performance of procedures for research purposes does not appear to adversely affect future health-care decisions.     

作为携带、沉积纳米荧光粉颗粒和纳米铁电体颗粒到FEDs 和 EL 器件上的载体的可印刷的油墨、粘结剂

文章介绍了两种移植和可控纳米沉积荧光粉颗粒和纳米铁电体颗粒的载体.第一种载体是一种可以悬浮和沉积合成的具有亚微米级尺寸大小的荧光粉颗粒的油墨.解决了该油墨的聚集和沉降问题,并发现该油墨具有良好的液流学性能,从而可用于印刷高分辨率的荧光粉.测量了相关的单个象素的阴极发光密度以评定这种丝网印刷油墨的可重复性.第二种载体是一种粘结剂,这种粘结剂不仅可以携带 30 μm 以及更大的尺寸的电致发光的荧光粉,还可以携带纳米铁电体颗粒.这种新型的粘结剂可应用于不需要额外的绝缘反射层的低造价的 EL 显示器.从衬底按要求将发射层剥下来就形成了柔性薄膜,将该薄膜置于两电极之间,仍可保持其电致发光的活性.该粘结剂薄膜可以很容易地印刷和定型制成显示屏.     

Optimised relay selection for route discovery in reactive routing

On-demand routing protocols have the potential to provide scalable information delivery in large ad hoc networks. The novelty of these protocols is in their approach to route discovery, where a route is determined only when it is required by initiating a route discovery procedure. Much of the research in this area has focused on reducing the route discovery overhead when prior knowledge of the destination is available at the source or by routing through stable links. Hence, many of the protocols proposed to date still resort to flooding the network when prior knowledge about the destination is un-available. This paper proposes a novel routing protocol for ad hoc networks, called On-demand Tree-based Routing Protocol (OTRP). This protocol combines the idea of hop-by-hop routing (as used by AODV) with an efficient route discovery algorithm called Tree-based Optimised Flooding (TOF) to improve scalability of ad hoc networks when there is no prior knowledge about the destination. To achieve this in OTRP, route discovery overheads are minimised by selectively flooding the network through a limited set of nodes, referred to as branching nodes. The key factors governing the performance of OTRP are theoretically analysed and evaluated, including the number of branch nodes, location of branching nodes and number of Route REQuest (RREQ) retries. It was found that the performance of OTRP (evaluated using a variety of well-known metrics) improves as the number of branching nodes increases and the number of consumed RREQ retries is reduced. Additionally, theoretical analysis and simulation results shows that OTRP outperforms AODV, DYMO, and OLSR with reduced overheads as the number of nodes and traffic load increases.     

Mechanism of Salmonella reduction in fermented pig feed

To protect consumers from Salmonella infection acquired through the consumption of pork meat, it is necessary to eradicate Salmonella from pork. In order to achieve this, the whole pork production chain should be free from Salmonella, including the pigs at the farm. In epidemiological studies it was concluded that the use of fermented feed plays a significant role in the reduction of Salmonella prevalence in pig farms. However, the mechanism of Salmonella reduction in fermented feed is not known. A controlled feed fermentation was performed using a pure culture of Lactobacillus plantarum. pH reduction, organic acid profiles and bacterial counts were determined. In L plantarum‐fermented feed, lactic acid and acetic acid were produced and the pH dropped to a value below 4.0. Antimicrobial products (bacteriocins) could not be detected. The results showed that the produced lactic and acetic acid and the pH in the feed are responsible for Salmonella reduction in fermented feed. L plantarum did not show any other antimicrobial effect on Salmonella. © 2000 Society of Chemical Industry     

T-lymphocytes from AIDS patients are unable to synthesize ribonucleotides de novo in response to mitogenic stimulation. Impaired pyrimidine responses are already evident at early stages of HIV-1 infection

Proliferative defects have been reported at the level of DNA synthesis, even in T-lymphocytes from asymptomatic human immunodeficiency virus type-1+ (HIV-1+) patients. Since purine and pyrimidine ribonucleotide availability is crucial for proliferation, we compared the ability of HIV-1- and HIV-1+ T-lymphocytes (> 95% CD4+ and CD8+) to activate de novo biosynthetic and salvage pathways following phytohemagglutinin stimulation using 14C-labeled precursors. The striking abnormality already detectable in asymptomatic patients' cells was the impaired ability of CTP, UDP-Glc, and UTP pools to expand over 72 h (44-70% of control), although ATP and GTP pools and responses were normal. In symptomatic patients, resting T-cells showed markedly reduced pyrimidine pools (53-74% of control) with no change following activation. Relatively normal ATP, GTP, and NAD pools masked the same impaired response of de novo synthesis to activation, with ATP and GTP being reduced by 50% at 48 h. Purine salvage was more active than the control in unstimulated HIV-1+ cells. This impaired de novo synthesis in HIV-1+ T-lymphocytes severely restricts the availability of ribonucleotides for vital growth-related activities such as membrane expansion and strand break repair as well as DNA and RNA synthesis. The data indicate that resting T-lymphocytes from symptomatic patients survive through enhanced salvage, but the stimulation induces metabolic cell death, and provide an explanation for the activation-associated lymphocyte death seen in HIV-1+ T-lymphocytes.     

Ladars for construction assessment and update

Work at the National Institute of Standards and Technology (NIST) on laser radar imaging of a construction site is described. The objective of the NIST research is to make measurements required in a construction project quicker and cheaper than current practice and to do so without impacting existing operations. This can be done by developing techniques for real-time assessment and documentation in terms of 3-D as-built models of the construction process. Once developed, this technology may be used for other applications such as condition assessment of a hazardous environment where human intervention would be impossible.