北京市区大气真菌粒子的沉降量

本工作用平皿沉降法在北京市西单观测了大气真菌粒子的沉降量。结果表明,大气真菌粒子的年平均沉降量为11.1个/皿·5分;一天内,大气真菌粒子沉降量出现7:00、19:00二个高峰时和13:00、凌晨4:00二个低峰时。结果同时表明,大气真菌粒子的沉降量夏季高,秋季低;白天与夜间的沉降量变化不大。     

沈阳市大气细菌粒子沉降量的观测

用平皿沉降法对沈阳市大气细菌粒子的沉降量是进行了1年的观测。结果表明,沈阳市大气细菌粒子的年平均沉降量为169.0个/皿5min;1年中,大气细菌粒子沉降量秋季大,冬季明显小;1天中,8时和17～18时为大气细菌粒子沉降量的2个高峰时,13时和夜间1～2时为2个低谷时;商业繁华区和交通干道两侧大气细菌粒子沉降量大,市郊清洁区沉降量小;白天比夜间沉降量大。     

沈阳市大气微生物的研究5、大气真菌粒子的沉降量

本文用平皿沉降法对沈阳市大气真菌粒子沉降量进行了一年的观测.结果表明,沈阳市大气真菌粒子的年平均沉降量为15.1个/皿5min;一年中,大气真菌粒子沉降量秋季大,冬季明显小;一天中,21:00时为大气真菌粒子沉降量的高峰时;造纸厂大气真菌粒子沉降量大,市郊清洁区沉降量小。     

大气细菌粒子含量测定的探讨

本工作用ANDERSEN生物粒子采样器法和平皿沉降法在北京西单对大气细菌粒子的含量进行了一年的对比观测实验。结果表明,在同次采样中,放置的采样皿数对测定结果没有明显影响;大气细菌粒子的沉降量与大气细菌粒子的含量有非常显著的正相关关系;由奥梅梁斯基公式计算的大气细菌粒子的含量明显偏高;由本实验得出的关系式能比较准确、简便的计算大气细菌粒子的含量。     

沉降法测定大气真菌粒子含量的探讨

本工作用 ANDERSEN 生物粒子采样器法和平皿沉降法在北京西单对大气真菌粒子的含量进行了一年的对比观测实验。结果表明,在同一次大气真菌粒子沉降量的采样中,放置的采样皿数对测定结果没有明显影响。大气真菌粒子沉降量与大气真菌粒子含量呈非常显著的正相关关系。由本实验得出的关系式能较准确、简便的计算大气真菌粒子的含量。     

大气中沉降微生物粒子含量换算方法探讨

平板沉降法常用于测定大气中沉降微生物粒子含量 ,但因结果的计量单位等不同 ,对不同地区大气微生物粒子含量评价比较造成困难。本文将不同检测者测定结果换算成统一的计量单位CFU/ (cm2 ·min)或CFU/ (m3·min)以比较不同地区大气中沉降微生物粒子含量。空气沉降微生物粒子含量的计算　平板沉降法常用菌落/皿或奥氏公式〔1,2〕 计算结果 (个 )菌 /m3 表示。但由于不同检测者选用平皿直径大小不等 (7～ 11cm)、平板暴露空气中的时间不同 (5～ 3 0min)、结果的计量单位〔(个 )菌 /m3 或菌落 /皿、菌落 / (皿·min)、CFU /m3 等〕不同 ,…     

大气细菌粒子浓度的时间分布特征及最佳采样时间的研究

用ＭＦ－４５型和ＨＴＫ－２０１型空气微生物采样器分别在北京、天津和沈阳三地观测了不同季节和一天中大气细菌粒子的浓度及其变化。结果表明：京、津二地春季大气细菌粒子浓度高，分别为２０５３个／ｍ３和２５５６个／ｍ３；夏季低，分别为９９５个／ｍ３和１０６４个／ｍ３。沈阳秋季大气细菌粒子浓度高，为１０１０８个／ｍ３；冬季低，为１２９４个／ｍ３。一天中，大气细菌粒子浓度呈双峰型变化，６：００～７：００和１８：００时大气细菌粒子浓度高，１１：００～１３：００和１：００～２：００时大气细菌粒子浓度低。根据大气细菌粒子浓度的季节变化和一天中大气细菌粒子浓度的时间分布特征，经过京、津、沈三地一天中分别１２次、８次、６次和４次不同采样时间组合的大气细菌粒子浓度的数理统计分析，大气细菌粒子浓度的监测拟集中在一年冬、春、夏、秋四季的中间月份，即１月、４月、７月、１０月进行；一天中采样８次的时间序列可为７：００、１０：００、１３：００、１６：００、１９：００、２２：００、１：００、４：００一天采样４次的时间序列可为５：００、１１：００、１７：００、２３：００。白天采样４次的时间序列可为春、秋季６：００、９：００、１２：００、１５：００?     

沉降法测定大气真菌粒子含量公式的检验

在沈阳市对作者提出的由大气真菌粒子的沉降量计算大气真菌粒子含量的公式进行了检验。结果表明，在沈阳市由作者公式计算的大气真菌粒子含量为１８２４个／ｍ￣３，Ａ·Ｓ采样器测定的大气真菌粒子含量为１８０７个／ｍ￣３　，二者之间的比值为１．０，ｔ＝０．０９８，Ｐ＞０．５０，两种方法得出的大气真菌粒子的含量非常相近。经验证，本公式是一个准确、简便的计算大气真菌粒子含量的公式。     

粒子数校正对空气微生物采样效果的影响

用活性生物粒子校正式对１９８７～１９８８年在北京西单６级ＡＮＤＥＲＳＥＮ生物粒子采样器采集的大气细菌粒子数进行校正。结果表明，ＡＮＤＥＲＳＥＮ生物粒子采样器采样３ｍｉｎ，空气取样量８４．９Ｌ，采集的大气细菌粒子数平均为２５７个，校正后的大气细菌粒子数平均为３１５个，校正后的大气细菌粒子数明显高于校正前的大气细菌粒子数，ｔ＝２．０１２，Ｐ＜０．０５。ＡＮＤＥＲＳＥＮ生物粒子采样器第１级（＞８．２μｍ）采集的大气细菌粒子数平均为９８个，校正后的大气细菌粒子数平均为１３６个，校正后的大气细菌粒子数明显高于校正前的大气细菌粒子数，ｔ＝２．４０９，Ｐ＜０．０５；第２级（６．０～８．２μｍ）～第６级（＜０．６５μｍ）各级校正后的大气细菌粒子数与校正前的大气细菌粒子数没有明显差别，ｔ＝１．７０１～０．０２６，Ｐ值均＞０．０５。粒数校正对ＡＮＤＥＲＳＥＮ生物粒子采样器采集的大气细菌粒子的大小分布和大气细菌粒子浓度的日变化的影响不明显。     

某医学院学生宿舍空气细菌总数监测

为了解某医学院学生宿舍空气微生物污染情况,笔者于2008年12月16日至20日早晨起床和上午11:00-12:00两个时间段,按照GB/T 17220-1998<公共场所卫生监测技术规范>布设采样点,采用自然沉降法对该校园内建筑结构及朝向相同的男生和女生宿舍进行空气细菌总数的监测,自然沉降法≤30 cfu/皿为合格~([1]).     

Sleepiness and road accidents among policemen on shif-work on Italian highways: study of the national highway network in the period of 1993-1997

Sleep disorders and daytime sleepiness are the most frequent disturbances reported by shift-workers. Sleepiness and fatigue can increase the risk of human errors and accidents especially during night work. In order to evaluate the time distribution and the possible role of sleepiness on road accidents in policemen on shift-work on highway patrols over 24 hours, we analyzed 1218 car accidents that occurred on the Italian highway network in the period 1993-1997. Accidents occurring during day shifts were significantly correlated with traffic density while accidents occurring during night shifts were not. During the 19:00-01:00 h shift the number of accidents showed a progressively increasing trend with two significant peaks around 23:00 and 01:00 h. Accidents occurring during the 01:00-07:00 h shift did not show significant trends. Information about sleep habits before starting night shifts were obtained by means of telephone interviews. While 85% of the subjects usually took a nap (30-90 min) before the 01:00-07:00 h shift only 15% took a short nap (< 30 minutes) before the 19:00-01:00 h shift. The data can be interpreted as a balance between circadian factors, homeostasis and fatigue related influences and spontaneously adopted counteracting strategies to increase the level of vigilance during night work hours. While a long nap seems to reduce the risk of accidents during the 01:00-07:00 h shift, policemen seem to underestimate the risk of sleepiness during the shift 19:00-01:00 h shift.     

Effects of consecutive night shifts with prolonged on-duty and overtime work on various sleep

The purpose of this research was to investigate the effect of consecutive night shifts upon various types of sleep. The subjects studied were 9 guards who usually worked on an alternate-day shift system. The nighttime nap EEG (3:00-6:30) during the 24-hr on-duty period was recorded, and then the subsequent day sleep EEG (11:00 to spontaneous awakening) and recovery night sleep (23:00 to spontaneous awakening) were also measured. These records were made for the nap, day sleep and recovery night under two different sets of conditions. The first was for the usual shift cycle (U), i.e. 24 hr duty (10:00-10:00)----off duty----24 hr duty----off duty. The other was for consecutive night shifts (CN) with overtime work (18:00-10:00) performed on the normal off day, i.e. 24 hr duty----8 hr off duty----40 hr duty----off duty. The results were as follows: There was no difference between U and CN conditions concerning time in bed and total sleep time in the nighttime nap, day sleep and recovery night. However, the total time of daytime sleep was significantly shortened under both U and CN conditions, as compared with the control night. The amount of REM sleep in the CN condition for both the nighttime nap and day sleep was significantly greater than in the U condition. In the recovery night, REM sleep continued to be slightly greater for the CN condition than for the U condition. Slow wave sleep (SWS) in the CN condition was slightly greater than in the U condition for the nighttime nap and day sleep, but in the recovery night, no difference was observed between the two conditions. In the U condition, the sleep onset REM period (SOREMP) was observed in 2 of the 9 cases, but only during the day sleep. In the CN condition, however, it occurred in 5 subjects during the nighttime nap, in 4 during the day sleep, and in 2 during the recovery night. The REM sleep latency in the CN condition thus tended to be diminished in each type of sleep compared with that in the U condition, but a significant difference between the two conditions was observed only in the nighttime nap. It is believed that the increase in the amount of REM sleep and in the frequency of SOREMP might be due to the repeated pattern of sleep loss and shortened periods of sleep during consecutive night shifts of prolonged duty, with partial sleep deprivation resulting from lack of REM sleep.     

Effects of 2-hour nighttime nap on melatonin concentration and alertness during 12-hour simulated night work

A nighttime nap is expected to mitigate melatonin suppression during night work by blocking light input to the retina, but it is unclear. In the present study, we investigated the effects of a nap break on melatonin level, subjective sleepiness, and vigilance performance during simulated night work. Eleven healthy young males (mean ± SD age: 22.2 ± 4.1 years) participated in counterbalanced crossover design experiments with two conditions (nap vs. no nap). The subjects performed 12-hour simulated night work from 21:00 to 09:00 h (illuminance: ∼500 lx). Subjects with a nap condition took a nap for 2 hours in a dark room from 03:00, while subjects with a no nap condition continued the simulated night work. The results showed that immediately after the 2-h nap break, the melatonin level at 05:00 h temporarily recovered from light-induced melatonin suppression during the simulated night work but significantly suppressed again at 07:00 and 09:00 h. Subjective alertness and vigilance performance were impaired immediately after the nap break but subsequently enhanced. The results suggest that a single nap break for 2 hours could be a strategy to enhance alertness during the last part of night shift but inadequate for mitigating melatonin suppression.     

Anopheles minimus: its bionomics and role in the transmission of malaria in Assam, India.

Indoor, day-resting collections of Anopheles minimus mosquitos from human dwellings in the study area in Assam, India, indicated that these insects were prevalent throughout the year and that their maximum abundance occurred from March to August. A. minimus was identified as a vector of malaria, and sporozoite infections were recorded every month of the year, with the highest rating occurring in October. The mosquito was highly anthropophilic and fed on human hosts (indoor) all through the night, but feeding was more pronounced between 01:00 and 04:00, the person-biting rate was 13.7 per night. Breeding occurred throughout the year in slow-flowing streams with grassy banks. A. fluviatilis was also identified as a vector of malaria in the study area but occurred in low density, and sporozoite infections were only seasonal.     

急诊科实行值班护士长工作制的作用及效果

目的通过护士长值班制保证急诊夜间对于突发事件的处理能力,并且保证夜间护理工作质量,减少护患纠纷。方法自2005年4月至今实行急诊护士长翻班制,值班护士长夜间值班时间：17：00～23：00,6：00～8：00。结果实行护士长值班制后急诊未发生一例护理差错事故,夜间护理质量得到了提高,急诊患者的满意率由90％上升至95％;抢救成功率由95％上升至98％。结论急诊科实行值班护士长工作制提高了护理质量,保证了护理安全,减少了急诊护理工作人员的心理压力,值得各医院推广。     

Effects of night work on urinary excretion rates of 6-sulfatoxymelatonin, norepinephrine and estriol in pregnant women

It has been suggested that shift work, night work in particular, affects worker's psychophysical health. However, the effects of night work on the health of pregnant women are not physiologically well elucidated. The effects of night work on the biological function of pregnant women were studied in the present study. Three pregnant and six non-pregnant nurses that engaged in fast-rotating shift system cooperated for the study. The 24-h urine samples were collected in two time frames, daytime (07:00 to 23:00) and nighttime (23:00 to 07:00) on the day shift, the night shift and the days off. Urinary concentrations of 6-sulfatoxymelatonin and norepinephrine were measured by enzyme-linked immunosorbent assay and estriol by radioimmunoassay. The excretion profiles of urinary 6-sulfatoxymelatonin in the pregnant and the non-pregnant women were altered on the night shift, which might relate the derangement of circadian rhythm of melatonin secretion. The urinary norepinephrine level during the night work was considerably higher in the pregnant women, which indicated the presence of higher physical burden in them due to the night work. The urinary estriol level was not significantly affected by shift, day/night and individual factors, and the effect of night work on urinary estriol level of the pregnant women remained uncertain. The results of the present study suggested that the night work of the pregnant shift workers should be much more relieved.     

Hourly frequency and seasonality of Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae) on São Luís Island, Maranhão, Brazil

This article presents the hourly and seasonal distribution of the Lutzomyia longipalpis sand fly captured on S?o Luís Island, Maranh?o State. A total of 11,200 specimens were captured during monthly use of CDC light traps indoors and in animal sheds, between 6:00 PM and 6:00 AM, in 1996 and 1997. The sand fly behaved as an annual species, with a high frequency year-round, while it was most abundant during the rainy season (57.2%) as compared to the dry season (42.8%). The highest frequencies during the rainy season occurred in January and April and in the dry season in July and November. The species was found all night long, mainly between 6:00 PM and 10:00 PM in animal sheds and between 8:00 PM and 2:00 AM indoors.     

An occupational health physician's report on the improvement in the sleeping conditions of night shift workers

This paper reviews briefly our research findings on sleep and health for shift workers at a bakery and a dish factory and aims to give some information on health protection with improved sleep. Our medical examinations revealed that rises in blood pressure (BP) were frequently observed in male bakery workers on the fixed night shift. They took a two-hour nap from 1:00 to 3:00 during the night shifts according to our advice. As a result, their diastolic BP significantly decreased in subsequent years. Women working shifts before 3:00 at a dish factory seemed to show more sleep disturbance, higher daytime sleepiness, and more fatigue than those working shits from 3:00. Total sleep hours taken during the daytime was similar between two groups. Among the dish, factory workers who switched to midnight or night shifts, 70% reported slow recovery from fatigue and 30% felt deteriorated health. These women also reported increased efforts to obtain a deep sleep, probably making up for shortened sleep. Occupational physicians can act to improve shift work conditions through monitoring the health of workers, applying naps, and designing possible schedules to secure deep, sufficient sleep.     

Impact of nap length, nap timing and sleep quality on sustaining early morning performance

The study examined how nap length, nap timing and sleep quality affect early morning performance (6:00 to 8:00). Twelve students participated in a simulated nightshift schedule (22:00 to 8:00) where the length and timing of nocturnal naps were manipulated (0:00-1:00, 0:00-2:00, 4:00-5:00 and 4:00-6:00). A performance test battery was administered consisting of a psychomotor vigilance test, a logical reasoning test, and a visual analogue scale for subjective fatigue and sleepiness. The results showed that a 120-min nap sustained early morning performance better than a 60-min nap. Taking a nap earlier or later did not affect the neurobehavioral performance tests, although participants slept more efficiently during naps later in the night shift. A negative effect of a nocturnal nap during the night shift on subsequent daytime and nocturnal sleep was not observed in the sleep architecture. It still remains unclear whether slow wave sleep plays an important role in sustaining early morning performance. In terms of work safety and sleep health, the results suggest that a longer and later nap is beneficial during night shifts.