BACKGROUND & AIMS: A raw, pepperoni batter (75% porkH7 (> or = 2 x 10(7) cfu/g), mixed with non-meat ingredients, and then hand-stuffed into 55 mm fibrous casings to form sticks. The numbers of the pathogen were determined before stuffing, after fermentation, after drying/slicing, and after periods of storage. For storage, slices were packaged under air, vacuum or CO2 and stored at -20, 4 and 21 degrees C. Sticks were fermented at 36 degrees C and 85% relative humidity (RH) to < or = pH 4.8 and then dried at 13 degrees C and 65% RH to a moisture/protein ratio (M/Pr) of < or = 1.

6:1. Fermentation and drying resulted in the numbers of the pathogen decreasing by about 2 log10 units. During storage, the temperature rather than the atmosphere had the greater effect on pathogen numbers. The greatest reductions in numbers were observed during storage at 21 degrees C, when numbers decreased to about 2 and 3.8 log10 cfu/g within 14 days in product stored under air and vacuum, respectively, and a 5 log10 reduction was observed for both atmospheres within 28 days. Regardless of the storage atmosphere, numbers did not decrease below 3.6 or 3.7 log10 cfu/g after 90 days of storage at -20 or 4 degrees C, respectively. These data confirm that fermentation and drying are sufficient to eliminate only about 2 log10 cfu/g of E.

coli O157:H7 from fermented sausage, and that additional strategies, such as storage for at least 2 weeks at ambient temperature in air, are required to achieve a 5 to 6 log10 reduction in the numbers of the pathogen in sliced pepperoni.

背景与目标： 生的意大利辣香肠面糊 (75% porkH7 (> 或 = 2x10(7) cfu/g)，与非肉类成分混合，然后手工填充到55毫米的纤维肠衣中，形成木条。在填充前，发酵后，确定病原体的数量。干燥/切片后，以及储存一段时间后。为了储存，切片在空气、真空或二氧化碳下包装，储存在-20，4和21 ℃。将棒在36 ℃ 和85% 相对湿度 (RH) 下发酵至 <或 = pH 4.8，然后在13 ℃ 和65% ℃ 下干燥至水分/蛋白质比 (M/Pr) <或 = 1。
<强> 6:1.发酵和干燥导致病原体数量减少约2 log10单位。在储存期间，温度而不是大气对病原体数量的影响更大。在21摄氏度的储存期间观察到数量的最大减少，当在空气和真空下储存的产品在14天内数量分别降低到约2和3.8 log10 cfu/g时，并且在28天内观察到两个大气压的5 log10减少。不管储存气氛如何，在-20或4摄氏度下储存90天后，数字没有低于3.6或3.7 log10 cfu/g，这些数据分别证实，发酵和干燥足以消除发酵香肠中仅约2 log10 cfu/g的大肠杆菌。例如，在环境温度下在空气中至少保存2周，以使切成薄片的意大利辣香肠中的病原体数量减少5至6 log10。

BACKGROUND & AIMS: OBJECTIVES:This study aimed to evaluate the associations between ambient air pollutants, obesity, and kidney function. SUBJECTS/METHODS:We enrolled 3345 people who had undergone health checkups at Seoul National University Hospital. We recorded the annual average concentrations of ambient air pollutants, including particulate matter with an aerodynamic diameter of ≤10 μm (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO), in each subject's residential area. Various obesity traits, such as body mass index, waist circumference, and visceral and subcutaneous adipose tissue areas, were measured by quantified computerized tomography (CT), and kidney function was assessed in relation to estimated glomerular filtration rate as an indicator of kidney function. RESULTS:High PM10, NO2, SO2, and CO concentrations were significantly associated with decreased kidney function (β = -2.39 and standard error = 0.32, -1.00 and 0.31, -1.23 and 0.28, and -1.32 and 0.29, respectively), and with the prevalence of chronic kidney disease (CKD). The association between air pollutant concentrations and decreased kidney function, including CKD, was stronger among those with high abdominal adiposity, as defined by CT measurement. For example, the association between increased concentrations of air pollutants and the prevalence of CKD was stronger in the group with greater visceral adiposity than in the group with less visceral adiposity (aORs = 1.29 vs 1.16 for PM10, 1.42 vs 1.21 for SO2, and 1.27 vs 1.11 for CO). CONCLUSIONS:Long-term exposure to higher concentrations of air pollutants was unfavorably associated with kidney function and CKD prevalence, especially in people with abdominal obesity. This may indicate a high susceptibility to air pollutants in obese people.

背景与目标：

BACKGROUND & AIMS: PURPOSE:To evaluate the duration of room air tamponade and its associated factors. STUDY DESIGN:Retrospective cohort study METHODS: The present study reviewed the medical records of patients who received room air tamponade after vitrectomy between Jun 2015 and Dec 2016. The room air duration was assessed by patient interviews 2 weeks after surgery. Relationships between the variables and tamponade duration were determined using logistic regression analysis. The remaining air level was determined from medical records. RESULTS:The room air tamponade had dissipated by 11.1 ± 1.3 days after surgery. The duration was 11.2 ± 1.3 days for eyes with a spared posterior capsule, longer than the duration in other eyes (10.1 ± 0.9 days). Increased axial length was correlated with increased duration. Axial length and a spared posterior capsule were significantly correlated with tamponade duration. Its half-life was presumed about 3.3 days. The room air seems to be absorbed at a constant rate. CONCLUSION:The data suggest that room air tamponade remains in the vitreous cavity for an average of 11.1 days. Axial length and posterior capsule status were associated with duration.

背景与目标：

BACKGROUND & AIMS: :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.

背景与目标： : 已开发出一种新颖的整个天花板上部房间紫外线杀菌照射 (UVGI) 系统 [eggcrate ultraviolet (UV)]，该系统结合了开放式 “eggcrate” 吊顶面板和带有吊扇的裸露紫外线灯。上部房间的UVGI比机械通风更有效地进行空气消毒，安装和运营成本要低得多。传统的上部房间UVGI固定装置采用多个紧密间隔的水平百叶窗，以将紫外线限制在上部房间。这些百叶窗式固定装置可保护下层房间的乘员免受紫外线引起的眼睛和皮肤刺激，但固定装置效率的主要成本。在eggcrate UV系统中使用传统的上层UVGI灯具的灯和镇流器，即使灯发出的UV辐射没有变化，杀菌效果也得到了显着改善。上室UVGI空气消毒应用的这一根本变化应允许在全球范围内更广泛，更有效地应用UVGI，以减少空气传播感染。

BACKGROUND & AIMS: :This study was undertaken to determine whether there was a correlation between ambient ozone (O3) levels and number of hospital admissions for myocardial infarction (MI) in Taipei, Taiwan. Hospital admissions for MI and ambient air pollution data for Taipei were obtained for the period from 2006 to 2010. The relative risk (RR) of hospital admissions for MI was estimated using a time-stratified case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. For the single-pollutant model (without adjustment for other pollutants), increased RR for a number of MI admissions was significantly associated with higher O3 levels both on warm days (>23°C) and on cool days (<23°C). This observation was accompanied by an interquartile range elevation correlated with a 7% (95% CI = 2%-12%) and 17% (95% CI = 11%-25%) rise in number of MI admissions, respectively. In the two-pollutant models, no significant associations between ambient O3 concentrations and number of MI admissions were observed on warm days. However, on cool days, correlation between ambient O3 after inclusion of each of the other five pollutants, particulate matter (PM10 or PM2.5), sulfur dioxide (SO2), nitrogen dioxide (NO2) or carbon monoxide (CO), and number of MI admissions remained significant. This study provides evidence that higher levels of ambient O3 increase the RR of number of hospital admissions for MI.

背景与目标： : 这项研究旨在确定台湾台北的环境臭氧 (O3) 水平与心肌梗死 (MI) 住院人数之间是否存在相关性。在2006年2010年期间，获得了台北的MI住院人数和环境空气污染数据。使用时间分层的病例交叉方法 (控制天气变量，星期几，季节性和长期时间趋势) 来估计MI的住院相对风险 (RR)。对于单污染物模型 (不调整其他污染物)，在温暖的日子 (>23 °C) 和凉爽的日子 (<23 °C)，许多MI入院的RR升高与较高的O3水平显着相关。)。此观察结果伴随着四分位间距升高，分别与MI入院人数的7% (95% CI = 2%-12%) 和17% (95% CI = 11%-25%) 相关。在两种污染物模型中，在温暖的日子里，没有观察到环境O3浓度与MI入院次数之间的显着关联。然而，在凉爽的日子里，加入其他五种污染物，颗粒物 (PM10或PM2.5)，二氧化硫 (SO2)，二氧化氮 (NO2) 或一氧化碳 (CO) 后的环境O3之间的相关性以及MI的入院数量仍然很重要。这项研究提供了证据，表明较高的环境O3水平会增加MI住院人数的RR。

BACKGROUND & AIMS: :As the techniques to connect percutaneous coronary intervention (PCI) balloons and the inflation syringe vary in the instructions for use and in practice, we measured the amount of air in PCI balloons after testing three connection methods to an inflation syringe. Following the preparation using one of the three methods, 114 balloons and stent balloons were tested four times. Method 1 connected the syringe and the balloon catheter directly after purging and filling the lumen, while method 3 omitted the purging and filling process. With method 2, the catheter lumen was purged, filled and fully vented via a three-way valve. The primary endpoint answered whether air remained in the balloon, and if so, the secondary endpoint indicated the total volume of remaining air. The connection with a three-way valve achieved significantly less air in the inflated balloon as compared with either direct connection approach (27% vs. 44% and 51%; p = 0.015). For the direct connection, no significant difference between purging and filling the lumen prior to making the connection or not existed. According to these findings, the best method to connect a PCI balloon to the inflation syringe while removing air involves using a three-way valve.

背景与目标： : 由于连接经皮冠状动脉介入治疗 (PCI) 球囊和充气注射器的技术在使用说明书和实践中有所不同，我们在测试了三种与充气注射器的连接方法后测量了PCI球囊中的空气量。在使用三种方法之一制备之后，测试114球囊和支架球囊四次。方法1在吹扫和填充管腔后直接连接注射器和球囊导管，而方法3省略了吹扫和填充过程。使用方法2，通过三通阀清除，填充并完全排出导管腔。主要终点回答了气球中是否残留有空气，如果是，则次要终点指示剩余空气的总体积。与任一直接连接方式 (27% 相对于44% 和51%; p = 0.015) 相比，与三通阀的连接显著减少了充气气球中的空气。对于直接连接，在进行连接之前或不存在清除和填充管腔之间没有显着差异。根据这些发现，在去除空气的同时将PCI气球连接到充气注射器的最佳方法是使用三通阀。

BACKGROUND & AIMS: :The prevalence of habitual snoring has been extensively explored in paediatric populations. Although exposure to cigarette smoke increases the risk of habitual snoring in a dose-dependent fashion, the potential contribution of air quality to habitual snoring remains unclear. 6000 questionnaires were distributed to 6- to 12-year-old children attending public schools in five distinct neighbourhoods within the city of Tehran, Iran, that were preselected based on air quality measures. Habitual snoring was defined as loud snoring ≥3 nights per week. Information regarding clinical and family-related habitual snoring risk factors was also obtained. Descriptive statistics followed by adjusted risk assessments were conducted. Among the 4322 (72%) completed datasets, the prevalence of habitual snoring was 11.6%. Partition of habitual snoring rates according to neighbourhood air quality characteristics revealed significantly higher habitual snoring frequencies among children residing in neighbourhoods with greatest pollution (24.5% and 12.1% in South and Central neighbourhoods versus 7.0% and 7.7% in North and East neighbourhoods, respectively). The regional variance in habitual snoring was primarily accounted for by an integrated measure of air quality, even after controlling for other risk factors. Environmental air quality emerges as a significant and potentially modifiable contributor to the risk for developing habitual snoring during childhood.

背景与目标： : 习惯性打鼾的患病率已在儿科人群中得到广泛探讨。尽管暴露于香烟烟雾会以剂量依赖的方式增加习惯性打鼾的风险，但空气质量对习惯性打鼾的潜在贡献仍不清楚。向伊朗德黑兰市五个不同社区的公立学校就读的6至12岁儿童分发了6000份问卷，这些问卷是根据空气质量指标预先选择的。习惯性打鼾被定义为每周大声打鼾 ≥ 3晚。还获得了有关临床和家庭相关的习惯性打鼾危险因素的信息。进行描述性统计，然后进行调整后的风险评估。在4322 (72%) 完成的数据集中，习惯性打鼾的患病率为11.6%。根据邻里空气质量特征对习惯性打鼾率的划分表明，居住在污染最大的社区中的儿童习惯性打鼾频率明显更高 (南部和中部分别为24.5% 和12.1%，北部和东部分别为7.0% 和7.7%)。即使在控制了其他危险因素之后，习惯性打鼾的区域差异也主要是通过对空气质量的综合衡量来解释的。环境空气质量成为导致儿童时期习惯性打鼾风险的重要且潜在的可改变因素。

BACKGROUND & AIMS: :This study is designed to evaluate the various physiologic maneuvers (Valsalva, humming, breath-hold) for the potential prevention of air embolism during central venous catheter placement. Central venous pressure measurements were prospectively obtained in 40 patients undergoing central venous catheter placement. The average central venous pressure at baseline was 3.275 mm Hg (range = -4 to 16, SD = 5.99). The average central venous pressure during breath hold was 6.1 mm Hg (range = -6 to 24, SD = 7.99). The average central venous pressure during humming was 5.1 mm Hg (range = -4 to 20, SD = 6.4) The average central venous pressure during the Valsalva maneuver was 18.43 (range = -3 to 48, SD = 14.73). Forty percent of patients (16 of 40) had negative central venous pressures at rest, 25% (10 of 40) had negative pressures during breath hold, 20% (8 of 40) had negative pressures during humming, and 2.5% (1 of 40) had negative pressures during Valsalva maneuver. The average increases in central venous pressure during breath hold, humming, and Valsalva were 2.85, 1.82, and 15.2 mm Hg, respectively. The difference between pressures during Valsalva and other maneuvers was statistically significant (P <.05). The conclusion is that the Valsalva maneuver is superior to breath-hold and humming for increasing central venous pressure during central venous catheter placement and, therefore, it is more likely to prevent air embolism in cooperative patients.

背景与目标： : 本研究旨在评估各种生理动作 (Valsalva，嗡嗡声，屏气)，以预防中央静脉导管放置过程中空气栓塞的可能性。前瞻性地获得了40例接受中心静脉导管放置的患者的中心静脉压测量值。基线时的平均中心静脉压为3.275毫米Hg (范围 = -4至16，SD = 5.99)。屏气期间的平均中心静脉压为6.1毫米Hg (范围 = -6至24，SD = 7.99)。嗡嗡声期间的平均中心静脉压为5.1毫米Hg (范围 = -4至20，SD = 6.4)。Valsalva动作期间的平均中心静脉压为18.43 (范围 = -3至48，SD = 14.73)。40% 的患者 (40例中的16例) 在休息时中心静脉压力为负，25% 例 (40例中的10例) 在屏气期间有负压，20% 例 (40例中的8例) 在嗡嗡声期间有负压，2.5% 例 (40例中的1例) 在Valsalva操作期间有负压。屏气，嗡嗡声和Valsalva期间中心静脉压的平均升高分别为2.85，1.82和15.2毫米Hg。Valsalva期间的压力与其他动作之间的差异具有统计学意义 (P <.05)。结论是，在中心静脉导管放置过程中，Valsalva动作优于屏气和嗡嗡声，可提高中心静脉压，因此，在合作患者中，它更有可能预防空气栓塞。

BACKGROUND & AIMS: :Air quality in the UK, although vastly improved from the smogs of the 1950s, now faces a new set of challenges from a variety of sources and pollutants. Poor air quality has long been associated with urban areas, but it is becoming clear that many rural locations also have locations likely to exceed the UK Air Quality Strategy-objectives: This paper will examine the extent to which rural authorities have been engaged in the local air-quality management (LAQM) process, a new regime by which air quality control is being accomplished in the UK. Results are presented from a questionnaire survey of environmental health officers of 100 rural authorities undertaken in January 1999. The paper investigates both the technical aspects of the LAQM process as well as the management approaches. The current progress of rural authorities, and some of the problems they face, are discussed particularly in comparison with urban areas. It is concluded that some rural authorities with air pollution problems stemming either from within or outwith their borough, may face significant challenges from the LAQM review and assessment process, particularly where air pollution responsibilities have only relatively recently been addressed. Rural authorities seem to be embracing these new responsibilities enthusiastically, but it is almost inevitable that they will be trailing behind urban authorities who have several decades of experience and joint working to draw upon.

背景与目标： : 英国的空气质量虽然比20世纪50年代的烟雾有了很大的改善，但现在面临着来自各种来源和污染物的一系列新挑战。长期以来，恶劣的空气质量一直与城市地区有关，但越来越明显的是，许多农村地区的位置也可能超过英国的空气质量战略-目标: 本文将研究农村当局在多大程度上参与了当地的空气质量管理 (LAQM) 过程，英国正在实现空气质量控制的新制度。结果来自1999年1月对100个农村当局的环境卫生官员进行的问卷调查。本文研究了LAQM流程的技术方面以及管理方法。特别是与城市地区相比，讨论了农村当局目前的进展及其面临的一些问题。结论是，一些农村当局的空气污染问题源于其行政区内部或外围，可能面临LAQM审查和评估过程的重大挑战，特别是在空气污染责任最近才得到解决的地方。农村当局似乎正在热情地承担这些新的责任，但几乎不可避免的是，他们将落后于拥有数十年经验和共同努力的城市当局。

BACKGROUND & AIMS: :Cystathionine beta synthase (CBS) is a crucial regulator of plasma concentrations of homocysteine. Severe hyperhomocysteinemia due to CBS deficiency confers diverse clinical manifestations, notably pulmonary thrombotic disease. However, the association between hyperhomocysteinemia and chronic obstructive pulmonary disease is not well understood. To investigate the role of hyperhomocysteinemia in lung injury and pulmonary fibrosis, we analyzed the lung of CBS-deficient mice, a murine model of severe hyperhomocysteinemia. The degree of lung injury was assessed by histologic examination. Analysis of profibrogenic factors was performed by real-time quantitative reverse transcription-polymerase chain reaction. CBS-deficient mice develop fibrosis and air space enlargement in the lung, concomitant with an enhanced expression of heme oxygenase-1, pro(alpha)1 collagen type I, transforming growth factor-beta1 and alpha-smooth muscle actin. However, lung fibrosis was found in the absence of increased inflammatory cell infiltrates as determined by histology, without changes in gene expression of proinflammatory cytokines TNFalpha and interleukin 6. The increased expression of alpha-smooth muscle actin and transforming growth factor-beta1 emphasizes the role of myofibroblasts differentiation in case of lung fibrosis due to CBS deficiency in mice.

背景与目标： : 胱硫醚 β 合酶 (CBS) 是血浆同型半胱氨酸浓度的关键调节剂。由于CBS缺乏症引起的严重高同型半胱氨酸血症可提供多种临床表现，尤其是肺血栓性疾病。然而，高同型半胱氨酸血症与慢性阻塞性肺疾病之间的关系尚不清楚。为了研究高同型半胱氨酸血症在肺损伤和肺纤维化中的作用，我们分析了CBS缺陷小鼠 (严重高同型半胱氨酸血症的鼠模型) 的肺。通过组织学检查评估肺损伤程度。通过实时定量逆转录-聚合酶链反应对促纤维化因素进行分析。CBS缺陷型小鼠在肺中出现纤维化和气隙增大，伴随血红素oxygenase-1，I型pro(alpha)1胶原蛋白，转化生长factor-beta1和 α-平滑肌肌动蛋白的表达增强。然而，根据组织学确定，在没有增加的炎性细胞浸润的情况下发现了肺纤维化，而促炎性细胞因子TNFalpha和白介素6的基因表达没有变化。Α-平滑肌肌动蛋白和转化生长factor-beta1的表达增加强调了在小鼠中由于CBS缺乏引起的肺纤维化的情况下肌成纤维细胞分化的作用。

BACKGROUND & AIMS: :PM(10) aerosol samples were collected in Durg City, India from July 2009 to June 2010 using an Andersen aerosol sampler and analyzed for eight water-soluble ionic species, namely, Na(+), NH(4) (+), K(+), Mg(2+), Ca(2+), Cl(-), NO(3) (-) and SO(4) (2-) by ion chromatography. The annual average concentration of PM(10) (253.5 ± 99.4 μg/m(3)) was four times higher than the Indian National Ambient Air Quality Standard of 60 μg/m(3) prescribed by the Central Pollution Control Board, India. The three most abundant ions were SO(4) (2-), NO(3) (-), and NH(4) (+), with average concentrations of 8.88 ± 4.81, 5.63 ± 2.22, and 5.18 ± 1.76 μg/m(3), respectively, and in turn accounting for 27.1 %, 16.5 %, and 15.5 % of the total water-soluble ions analyzed. Seasonal variation was similar for all secondary ions i.e., SO(4) (2-), NO(3) (-), and NH(4) (+), with high concentrations during winter and low concentrations during monsoon. Varimax Rotated Component Matrix principal component analysis identified secondary aerosols, crustal resuspension, and coal and biomass burning as common sources of PM(10) in Durg City, India.

背景与目标： : 使用Andersen气溶胶采样器从2009年7月到2010年6月在印度杜尔格市收集了PM(10) 气溶胶样品，并分析了八种水溶性离子物种，即Na ()，NH(4) ()，K ()，Mg(2)，离子色谱法测定Ca(2 +) 、Cl(-) 、NO(3) (-) 和SO(4) (2-)。PM(10) 的年平均浓度 (253.5 ± 99.4 μ g/m(3)) 是印度中央污染控制委员会规定的印度国家环境空气质量标准60 μ g/m(3) 的四倍。三种含量最高的离子分别为SO(4) (2-) 、NO(3) (-) 和NH(4) (+)，平均浓度分别为8.88 ± 4.81、5.63 ± 2.22、5.18 ± 1.76 μ g/m(3)，并依次占所分析的总水溶性离子的27.1% 、16.5% 和15.5%。所有次级离子的季节变化相似，即SO(4) (2-)，NO(3) (-) 和NH(4) ()，冬季浓度高，季风浓度低。Varimax旋转成分矩阵主成分分析确定了二次气溶胶，地壳重悬以及煤炭和生物质燃烧是印度杜尔格市PM(10) 的常见来源。

BACKGROUND & AIMS: :Kinetic characteristics of n-butyl alcohol and iso-butyl alcohol in a composite bead biofilter were investigated. The microbial growth rate of n-butyl alcohol was greater than that of iso-butyl alcohol in the average inlet concentration range of 50-300 ppm. The microbial growth rate was inhibited at higher inlet concentration, and the inhibitive effect in the concentration range of 50-150 ppm was more pronounced than that in the concentration range of 150-300 ppm. The degree of inhibitive effect for n-butyl alcohol was more sensitive than that for iso-butyl alcohol in the concentration range of 50-150 ppm. The zero-order kinetic with the diffusion rate limitation could be regarded as the most adequate biochemical reaction model. The biodegradation rate of n-butyl alcohol was greater than that of iso-butyl alcohol in the average inlet concentration range of 50-300 ppm. The biochemical reaction rate was also inhibited at higher inlet concentration, and the inhibitive effect for iso-butyl alcohol was more pronounced than that for n-butyl alcohol. The factor of the chemical structure of compound was more predominant in the microbial growth and biochemical reaction processes. The maximum elimination capacity of n-butyl alcohol and iso-butyl alcohol were 55.7 and 34.8 g C h(-1)m(-3) bed volume, respectively. The compound with no side group in the main chain would be easier biodegraded by the microbial.

背景与目标： : 研究了复合珠生物滤池中正丁醇和异丁醇的动力学特性。在平均入口浓度为50 ~ 300 ppm时，正丁醇的微生物生长速率大于异丁醇。在较高的入口浓度下，微生物的生长速率受到抑制，并且在50-150 ppm的浓度范围内的抑制作用比在150-300 ppm的浓度范围内的抑制作用更明显。在50 ~ 150 ppm的浓度范围内，对正丁醇的抑制作用比对异丁醇的抑制作用更敏感。具有扩散速率限制的零级动力学可以被视为最适当的生化反应模型。在平均入口浓度为50 ~ 300 ppm时，正丁醇的生物降解率大于异丁醇。在较高的入口浓度下，生化反应速率也受到抑制，对异丁醇的抑制作用比对正丁醇的抑制作用更明显。化合物的化学结构因素在微生物生长和生化反应过程中更为重要。正丁醇和异丁醇的最大消除能力分别为55.7g C h(-1)m(-3) 床体积和34.8g C h(-1)m(-3) 床体积。主链中没有侧基的化合物将更容易被微生物生物降解。

BACKGROUND & AIMS: :Several studies have indicated weakly increased risk for kidney cancer among occupational groups exposed to gasoline vapors, engine exhaust, polycyclic aromatic hydrocarbons and other air pollutants, although not consistently. It was the aim to investigate possible associations between outdoor air pollution at the residence and the incidence of kidney parenchyma cancer in the general population. We used data from 14 European cohorts from the ESCAPE study. We geocoded and assessed air pollution concentrations at baseline addresses by land-use regression models for particulate matter (PM10 , PM2.5 , PMcoarse , PM2.5 absorbance (soot)) and nitrogen oxides (NO2 , NOx ), and collected data on traffic. We used Cox regression models with adjustment for potential confounders for cohort-specific analyses and random effects models for meta-analyses to calculate summary hazard ratios (HRs). The 289,002 cohort members contributed 4,111,908 person-years at risk. During follow-up (mean 14.2 years) 697 incident cancers of the kidney parenchyma were diagnosed. The meta-analyses showed higher HRs in association with higher PM concentration, e.g. HR = 1.57 (95%CI: 0.81-3.01) per 5 μg/m3 PM2.5 and HR = 1.36 (95%CI: 0.84-2.19) per 10-5 m-1 PM2.5 absorbance, albeit never statistically significant. The HRs in association with nitrogen oxides and traffic density on the nearest street were slightly above one. Sensitivity analyses among participants who did not change residence during follow-up showed stronger associations, but none were statistically significant. Our study provides suggestive evidence that exposure to outdoor PM at the residence may be associated with higher risk for kidney parenchyma cancer; the results should be interpreted cautiously as associations may be due to chance.

背景与目标： : 几项研究表明，在暴露于汽油蒸气，发动机废气，多环芳烃和其他空气污染物的职业群体中，患肾癌的风险增加很小，尽管并不一致。目的是调查居住地的室外空气污染与普通人群中肾脏实质癌的发生率之间的可能关联。我们使用了来自ESCAPE研究的14个欧洲队列的数据。我们通过土地利用回归模型对颗粒物 (PM10，PM2.5，pm粗，PM2.5吸光度 (soot)) 和氮氧化物 (NO2，NOx) 的基线地址的空气污染浓度进行了地理编码和评估，并收集了交通数据。我们使用Cox回归模型对队列特异性分析的潜在混杂因素进行校正，并使用随机效应模型进行荟萃分析，以计算汇总风险比 (HRs)。289,002队列成员贡献了4,111,908人年的风险。在随访期间 (平均14.2年)，诊断出697例肾实质癌。荟萃分析显示，较高的HRs与较高的PM浓度相关，例如每5 μ g/m3 PM2.5的HR  =   1.57 (95% CI: 0.81-3.01) 和每10-5 m-1 PM2.5的HR  =   1.36 (95% CI: 0.84-2.19)，尽管从来没有统计学意义。与最近街道上的氮氧化物和交通密度相关的hr略高于1。在随访期间未改变居住地的参与者中进行的敏感性分析显示，相关性更强，但无统计学意义。我们的研究提供了暗示性证据，表明在住所暴露于室外PM可能与较高的肾实质癌风险相关; 应谨慎解释结果，因为关联可能是偶然的。

BACKGROUND & AIMS: BACKGROUND:The authors conducted an in vivo study to determine if low-speed handpiece motors can become contaminated with oral flora when used with prophylaxis angles. METHODS:This crossover study involved 20 subjects, two types of handpieces and three prophylaxis angles. The authors used each handpiece/prophylaxis angle system to polish teeth. They then collected samples, spiral-plated the specimens and incubated them at 37 degrees C anaerobically and aerobically (with 5 percent carbon dioxide). After incubation, the authors examined the plates for the presence of bacterial colonies. RESULTS:At least 75 percent of the handpiece/prophylaxis angle systems used on the 20 subjects had bacterial contamination for at least one cultured area. Of the 420 specimens, 258 (61.4 percent) produced bacterial growth. Contamination varied from zero to 6,300 colony-forming units per milliliter. CONCLUSIONS:These data suggest that the internal surfaces of low-speed handpieces can become microbially contaminated during use with prophylaxis angles. CLINICAL IMPLICATIONS:Unless low-speed handpieces are sterilized properly after each use, they pose a risk for crossinfection.

背景与目标：

BACKGROUND & AIMS: :Highly portable, sensitive, and selective passive air samplers were used to investigate ambient volatile organic compound (VOC) levels at multiple sampling sites in an industrial city, Fuji, Japan. We determined the spatial distributions of 27 species of VOCs in three campaigns: Mar (cold season), May (warm season), and Nov (mild season) of 2004. In all campaigns, toluene (geometric mean concentration, 14.0microg/m3) was the most abundant VOC, followed by acetaldehyde (4.76microg/m3), and formaldehyde (2.58microg/m3). The spatial distributions for certain VOCs showed characteristic patterns: high concentrations of benzene and formaldehyde were typically found along major roads, whereas high concentrations of toluene and tetrachloroethylene (PCE) were usually found near factories. The spatial distribution of PCE observed was extremely consistent with the diffusion pattern calculated from Pollutant Release and Transfer Register data and meteorological data, indicated that passive air samplers are useful for determining the sources and distributions of ambient VOCs.

背景与目标： : 高度便携式，灵敏和选择性的被动空气采样器用于调查日本富士工业城市多个采样点的环境挥发性有机化合物 (VOC) 水平。我们在三个运动中确定了27种voc的空间分布: 3月 (寒冷季节)，五月 (温暖季节) 和11月 (温和季节) 2004年。在所有活动中，甲苯 (几何平均浓度，14.0微克/立方米) 是最丰富的VOC，其次是乙醛 (4.76微克/立方米) 和甲醛 (2.58微克/立方米)。某些voc的空间分布显示出特征模式: 通常在主要道路上发现高浓度的苯和甲醛，而在工厂附近通常发现高浓度的甲苯和四氯乙烯 (PCE)。观察到的PCE的空间分布与根据污染物释放和转移寄存器数据以及气象数据计算出的扩散模式极为一致，表明被动空气采样器可用于确定环境voc的来源和分布。