2012年天津市公共场所嗜肺军团菌污染状况

目的开展天津市公共场所嗜肺军团菌（简称军团菌）检测,了解该地区军团菌污染情况,为预防和控制军团菌病提供科学依据。方法随机抽取天津市大型公共场所水样共279份,进行军团菌分离培养与鉴定。结果采集的279份水样中,32份检出军团菌,空调系统用水检出率为15．23％,生活类用水检出率为2．44％。其中空调系统用水中冷却水污染最为严重（21．09％）。结论天津市公共场所中存在军团菌污染,对人群存在潜在健康风险,尤其是空调系统冷却水的污染最为严重,应注重加强天津市公共场所集中空调系统的日常监督和预防控制工作,同时深入开展清洗消毒效果评价。     

2011—2013年中山市公共场所集中空调通风系统清洗效果评价

目的评价中山市公共场所集中空调通风系统清洗效果。方法2011年1月—2013年3月,对该市57家公共场所集中空调通风系统进行清洗前后卫生状况检测,检测指标包括集中空调送风系统、风管系统、冷却系统,统计分析各项指标。结果清洗前后送风中PM,。、细菌总数、真菌总数,风管内表面积尘量、细菌总数、真菌总数,冷却水、冷凝水中嗜肺军团菌合格率显著升高（P〈0．05）,分别由46．81％、73．19％、52．64％,85．34％、76．87％、68．68％,40．51％提高至100％、92．65％、89．96％,100％、100％、98．5％,91．11％;清洗前后送风系统、风管系统各项检测指标平均水平均显著降低（P〈0．05）。结论该市57家公共场所集中空调通风系统清洗效果显著,应定期对其进行清洗消毒,降低集中空调卫生安全风险。     

上海市道路清扫保洁作业道班房设置和设计标准化研究

分析了目前上海市市容环卫作业道班房的现状,提出道班房的设置和设计的标准化要求.     

Glutathione peroxidase‐1 gene rescues cocaine‐induced conditioned place preference in mice by inhibiting σ‐1 receptor expression

The aim of this study was to investigate whether the glutathione peroxidase‐1 gene (GPx‐1) affects cocaine‐induced conditioned place preference (CPP) using a mouse model. Cocaine‐induced CPP was accompanied by an increase in the level of σ‐1 receptor in the nucleus accumbens (NAc). This phenomenon was more pronounced in the GPx‐1 gene knockout (GPx‐1 KO) than in wild type (WT) mice. In contrast, the CPP and expression of σ‐1 receptor were much less pronounced in GPx‐1‐overexpressing transgenic (GPx‐1 TG) mice than non‐transgenic (non‐TG) mice. Treatment of the mice with BD1047 , a σ‐1 receptor antagonist, significantly attenuated both cocaine‐induced CPP and c‐Fos‐immunoreactivity (c‐Fos‐IR) in WT and GPx‐1 KO mice, although the effects were more evident in the latter group. Despite the protective effects of BD1047 on cocaine‐induced CPP and c‐Fos in non‐TG mice, there were no additional protective effects in cocaine‐treated GPx‐1 TG mice, indicating that the σ‐1 receptor is a critical target for GPx‐1‐mediated psychoprotective activity. Overall, our results suggest that GPx‐1 attenuates cocaine‐induced CPP via inhibition of σ‐1 receptor expression.     

Impairments in experience‐dependent scaling and stability of hippocampal place fields limit spatial learning in a mouse model of Alzheimer's disease

Impaired spatial memory characterizes many mouse models for Alzheimer's disease, but we understand little about how this trait arises. Here, we use a transgenic model of amyloidosis to examine the relationship between behavioral performance in tests of spatial navigation and the function of hippocampal place cells. We find that amyloid precursor protein (APP) mice require considerably more training than controls to reach the same level of performance in a water maze task, and recall the trained location less well 24 h later. At a single cell level, place fields from control mice become more stable and spatially restricted with repeated exposure to a new environment, while those in APP mice improve less over time, ultimately producing a spatial code of lower resolution, accuracy, and reliability than controls. The limited refinement of place fields in APP mice likely contributes to their delayed water maze acquisition, and provides evidence for circuit dysfunction underlying cognitive impairment. © 2014 Wiley Periodicals, Inc.     

Hippocampal spatial mapping and the acquisition of competing responses

Response reversal learning is facilitated in many species, including humans, when competing responses occur in separate contexts. This suggests hippocampal maps may facilitate the acquisition of competing responses and is consistent with the hypothesis that contextual encoding permits rapid acquisition of new behaviors in similar environments. To test this hypothesis, the pattern of Arc expression was examined after rats completed a series of left/right response reversals in a T‐maze. This reversal training occurred in the same room, two different rooms, or within a single room but with the maze enclosed in wall‐length curtains of different configurations (i.e., black/white square or circle). Across CA1 and CA3, successive T‐maze exposures in the same room recruited the same cells to repeatedly transcribe Arc, while a unique population of cells transcribed Arc in response to each of two different rooms as well as to the two unique curtain configurations in the same room. The interference from original learning that was evident on the first reversal in animals without a context switch was absent in groups that experienced changes in room or curtain configuration. However, only the use of unique rooms, and not changes in the curtained enclosure, facilitated learning across response reversals relative to the groups exposed to only one room. Thus, separate hippocampal maps appear to provide protection from the original learning interference but do not support improved reversals over trials. The present data suggest changes in heading direction input, rather than remapping, are the source of facilitation of reversal learning. © 2013 Wiley Periodicals, Inc.     

Met and unmet need for personal assistance among community‐dwelling New Zealanders 75 years and over

Ageing in place initiatives that aim to keep older people out of hospitals and rest homes and in their own homes for longer have been at the forefront of aged care policy since the early 1990s. The success of these policies depends largely on the availability of a suitable home environment, a supportive social network and regular assessment to detect changes in the older person's health status and needs for support. The BRIGHT Trial was a randomised control trial investigating the effectiveness of introducing case finding in primary care settings to detect unmet need and risk of disability among older people. We used baseline questionnaire data collected in 2008–2009 from 3753 community‐dwelling older people to estimate and describe use and need for additional personal assistance. Logistic regression was used to identify the most important predictors of reporting some need for support and unmet need. Eighty‐one per cent of participants required support with at least one instrumental activity of daily living. Sixty‐six per cent were meeting their needs with the support they were currently receiving. Unmet need was most frequently reported for heavy housework (65%) and light housework (53%). While spouses, family members and friends were the main providers of support for light housework, meal preparation, shopping, finances and transportation, paid staff most frequently provided personal care and heavy housework assistance. Reporting mobility difficulty (OR = 3.5), identifying as a care provider (OR = 1.7) and being female (OR = 1.9) were all significant predictors of some need for assistance as well as unmet need for assistance (OR = 2.5, 1.7 and 1.7 respectively). The findings highlight the importance of regular needs assessment for older people living in the community particularly, given the reliance on spousal support for the majority of activities.     

Spatial orientation in Drosophila

Abstract: Spatial orientation is critical for many behaviors. Intrinsic to the oriented state is the knowledge of past, present, and future spatial location relative to one or more landmarks. How do animals so fluidly solve this problem? Determining mechanisms of orientation may benefit from investigation of relatively simple organisms. Two behaviors that presumably use path integration as a major input to orientation—place learning and persistent target selection—allow for the examination of cellular and neural circuit mechanisms in Drosophila. Although our understanding of these processes is still relatively immature, some recent findings provide insights into the mechanisms supporting orientation. First, place learning provides good access to the past, present, and future aspects of orientation, but currently is less open to understanding how a fly establishes a relationship to landmarks. The change in behavior after learning is orientation away from, and avoiding, a place predicted to punish a fly, incorporating all temporal aspects of orientation, and can last for minutes to hours. This conclusion is supported by several learning phenomena. Second, persistent target selection provides the best access to the processes determining relationships to landmarks. Using a disappearing visual-landmark paradigm, persistent target selection was shown to require parts of the central complex for a seconds-long “path integration memory.” How the path integration memory, on this short time scale, is related to longer lasting place memories is, as yet, unknown. Nevertheless, studies of place learning and persistent target selection may provide insights into orientation mechanisms in a simple brain.     

Environmental deformations dynamically shift human spatial memory

Place and grid cells in the hippocampal formation are commonly thought to support a unified and coherent cognitive map of space. This mapping mechanism faces a challenge when a navigator is placed in a familiar environment that has been deformed from its original shape. Under such circumstances, many transformations could plausibly serve to map a navigator's familiar cognitive map to the deformed space. Previous empirical results indicate that the firing fields of rodent place and grid cells stretch or compress in a manner that approximately matches the environmental deformation, and human spatial memory exhibits similar distortions. These effects have been interpreted as evidence that reshaping a familiar environment elicits an analogously reshaped cognitive map. However, recent work has suggested an alternative explanation, whereby deformation‐induced distortions of the grid code are attributable to a mechanism that dynamically anchors grid fields to the most recently experienced boundary, thus causing history‐dependent shifts in grid phase. This interpretation raises the possibility that human spatial memory will exhibit similar history‐dependent dynamics. To test this prediction, we taught participants the locations of objects in a virtual environment and then probed their memory for these locations in deformed versions of this environment. Across three experiments with variable access to visual and vestibular cues, we observed the predicted pattern, whereby the remembered locations of objects were shifted from trial to trial depending on the boundary of origin of the participant's movement trajectory. These results provide evidence for a dynamic anchoring mechanism that governs both neuronal firing and spatial memory.