光照度计法测量公共场所室内桌面照度不确定度评定

目的建立现场检测工作中室内桌面照度测量不确定度评定的方法,对不确定度分量进行评定,计算出扩展不确定度值。方法根据《测量不确定度评定与表示(JJF 1059.1-2012)》和《公共场所卫生检验方法第1部分:物理因素(GB18204.1-2013)》的方法,对现场测量公共场所(候诊室)室内桌面照度值的各不确定度分量进行分析和计算,最终合成标准不确定度。结果本例用照度计法对某候诊室室内照度进行测量结果为:(225±10.74)lx,扩展不确定度为10.74 lx,其中采样高度是最大不确定度分量。结论该评定方法可用于现场检测中照度值测量的不确定度评定。     

Solar heat load: heat balance during exercise in clothed subjects

Summary Six subjects exercised for 60 min on a cycle ergometer. Their backs were exposed to an artificial sun with a spectral distribution similar to sunlight and an intensity of 724 W m^–2. Each subject took part in four experiments in random order: wearing suits of polyester (insulation value = 0.5 clo), white (WP) or black (BP), or cotton (0.6 clo), white (WC) or black (BC). Measured by partitional calorimetry, the calculated heat losses and gains for the four conditions balanced within less than 10%. The differences between the short-wave radiation gains of subjects in white or black garments were small. This is due to the transparency of the white materials, which allows a larger percentage of the radiation to penetrate the clothing. The surface temperatures of the sun-exposed areas were very high, especially in the black suits. This promotes dry heat loss. Therefore the sweat loss in the black suits and the differences between the black and white clothes became relatively small. The physiological strain in steady-state exercise, as expressed by average heart rates, was 142 (WP), 154 (BP), 151 (WC), and 160 (BC) beats min^–1; the sweat losses were 649 (WP), 666 (BP), 704 (WC), and 808 (BC) g. For both of these measures values for white polyester were significantly less than those for black cotton.     

Maculopatía fótica: revisión de la literatura (ii)

The human retina, as transducer of light energy, is especially exposed to light toxicity. Solar maculopathy has been the only form of photic maculopathy for millennia, often secondary to the observation of an eclipse. During the last century, technological advances have led to the appearance of new forms of photic maculopathy, related to the exposure to new forms of artificial light, such as welding devices and lasers. In recent years the general use of laser pointers has led to an upturn in interest in this pathology. The aim of this review is to offer an integrated view of the different types of photic maculopathy. Due to the extension of the topic, the review is presented divided into 2 parts. In this second part, atomic bomb maculopathy, laser maculopathy, iatrogenic forms of photic maculopathy, and foveomacular retinitis are presented.     

Dosis eritematosa mínima: correlación con el fototipo y método de medición en una muestra de población colombiana

Background and objectiveThe minimal erythema dose (MED), an essential measurement in studies of skin photosensitivity, requires establishing MED values for specific populations, given genetic variation. Different ways to assess erythema are also relevant. We aimed to determine MED values in a sample of Colombian patients and correlations between MED and Fitzpatrick skin type. We also studied concordance correlation between MEDs and two alternative ways to assess erythema.Patients and methodsCross-sectional study of 113 individuals in Bogotá, Colombia. We used a solar simulator to measure UV-A radiation and combined UV-A and UV-B (UVA + UVB) radiation, o se podría suprimir este término porque UVA y UVB son términos conocidos for MED calculation. Narrowband UV-B (NBUVB) radiation was measured in a phototherapy cabin. Erythema was assessed visually and with a Mexameter MX 18 device.ResultsThe median MEDs of UVA + UVB radiation were 22 mJ/cm² for Fitzpatrick skin types I and II, and 33 and 43 mJ/cm², respectively, for types III and IV. The MEDs of UV-A radiation were 22, 42, 86, and 100 J/cm² for types I, II, III, and IV, respectively. The MEDs of NBUVB light were 390, 550, 770, and 885 mJ/cm² for the 4 skin types. The correlation between MEDs and skin types ranged from 0.5 to 0.69. Lin's concordance correlation coefficients between visual and Mexameter assessments of erythema were greater than 0.8 in all cases.ConclusionThis study allowed us to understand MED values for UV-A, UVA + UVB, and NBUVB according to different skin types in the Colombian population. Concordance correlation coefficients between the different methods of erythema assessment were very good. Correlations between MEDs and skin types were moderate to good.     

When are solar refrigerators less costly than on-grid refrigerators: A simulation modeling study

BackgroundGavi recommends solar refrigerators for vaccine storage in areas with less than eight hours of electricity per day, and WHO guidelines are more conservative. The question remains: Can solar refrigerators provide value where electrical outages are less frequent?MethodsUsing a HERMES-generated computational model of the Mozambique routine immunization supply chain, we simulated the use of solar versus electric mains-powered refrigerators (hereafter referred to as “electric refrigerators”) at different locations in the supply chain under various circumstances.ResultsAt their current price premium, the annual cost of each solar refrigerator is 132% more than each electric refrigerator at the district level and 241% more at health facilities. Solar refrigerators provided savings over electric refrigerators when one-day electrical outages occurred more than five times per year at either the district level or the health facilities, even when the electric refrigerator holdover time exceeded the duration of the outage. Two-day outages occurring more than three times per year at the district level or more than twice per year at the health facilities also caused solar refrigerators to be cost saving. Lowering the annual cost of a solar refrigerator to 75% more than an electric refrigerator allowed solar refrigerators to be cost saving at either level when one-day outages occurred more than once per year, or when two-day outages occurred more than once per year at the district level or even once per year at the health facilities.ConclusionOur study supports WHO and Gavi guidelines. In fact, solar refrigerators may provide savings in total cost per dose administered over electrical refrigerators when electrical outages are less frequent. Our study identified the frequency and duration at which electrical outages need to occur for solar refrigerators to provide savings in total cost per dose administered over electric refrigerators at different solar refrigerator prices.     

The Effects of Spectral Power Distribution and Illuminance Levels on Key Parameters in the Male Golden Hamster and Rat With Preliminary Observations on the Effects of Pinealectomy

Three different light sources were used to determine the effects of spectral power distribution (SPD) and illuminance levels on growth and organ weights of male golden hamsters and rats. SPD had little effect on organ weights or measurements of either rats or hamsters. However, responses to illuminance levels were quite apparent, provided they were equalized for the scotopic eye sensitivity curve characteristic of nocturnal animals. Under seven illuminance levels from 0 to 3.9 scotopic fc, hamsters demonstrated graded responses in gonadal weights and presumed function from 0 to 0.02 scotopic fc. Above this level, photopic saturation was apparent. The neuroendocrine system of pinealectomized animals failed to show sensitivity to illuminance levels. The suggestion is made that the pineal gland acts to monitor illuminance levels (below about 0.02 scotopic fc) as well as photic duration. While the latter appears to be an "all or none" effect, the former appears to be graded.     

缺血性脑卒中患者发病节气与证型的相关性研究

目的 探究缺血性脑卒中发病节气与证型的相关性。方法 选取2021年天津中医药大学第一附属医院住院病历系统中4 838例缺血性脑卒中患者,使用频数分布统计法对其性别、年龄、发病节气、中医证型等信息进行分析,计算患者的发病日期对应的发病节气,然后分析缺血性脑卒中的发病节气与中医证型的相关性;使用圆形分布统计法探究发病节气、中医证型的高峰点。结果 4 838例患者中,男性3 233例（66.8%）,女性1 605例（33.2%）;60~69岁有1 814例（37.5%）,为发病人数最多的年龄段;阴虚动风证2 268例（46.9%）,风痰阻络证1 231例（25.4%）,两者为最常见的证型;清明为发病率最高的节气,总体发病节气无绝对高峰期,惊蛰为阴虚动风证发病高峰,小满为风痰阻络证发病高峰。结论 缺血性脑卒中患者男性多于女性,60~69岁年龄段发病人数最多,整体发病不存在绝对高峰节气,阴虚动风、风痰阻络两种证型的发病存在高峰期,阴虚动风证的发病高峰节气是惊蛰,风痰阻络证的发病高峰节气为小满,提示二十四节气内均可发病,重点人群要积极且持续的预防。     

太阳能热水系统在医院洗浴热水供应中的应用

文章通过太阳能热水系统与热媒换热系统、空气源热泵热水机组系统联合应用于山东省某医院洗浴热水系统中的实例,论述了系统的组成和工作原理,并分析其经济性。     

Operational implications of varying ambient light levels and time-of-day effects on saccadic velocity and pupillary light reflex

Changes in maximal saccadic velocity (SV), initial pupil diameter (IPD), constriction latency (CL) and constriction amplitude (CA) determined by the pupillary light reflex have been found to be sensitive indicators of impairment as a result of drugs, sleepiness, and/or fatigue. Ambient illuminance and time of day are controlled when these indices are applied as repeated measures in fitness-for-duty determinations. The application of oculometrics in unrestricted operational environments, where ambient illuminance and time-of-day testing are not constant, requires understanding of, and potential compensation for, the effects of, and interactions among, these multiple uncontrolled variables. SV, IPD, CL, and CA were evaluated in the morning and evening on two consecutive days following adequate nightly sleep under one baseline ambient illuminance and seven test ambient illuminances. Sixteen healthy volunteers (21-38 years, eight females/eight males) participated. Within and across days, SV was unaffected by decreasing ambient light or time-of-day effects. With the increase of ambient light from 670 to 3300 lx, CL decreased by 1%, while IPD and CA decreased by 17% and 20%, respectively. IPD increased with time of day by 1-10% (IPD was smaller in the morning). The results show that SV and CL are essentially resistant to changes in ambient light and time-of-day effects, simplifying their application in uncontrolled operational environments.     

Fe3+/TiO2-xNx太阳光下降解亚甲基蓝的研究

目的:采用溶胶-凝胶法制备一系列不同Fe3 掺杂量的复合纳米Fe3 /TiO2-xNx光催化剂,建立以太阳为光源高效降解亚甲基蓝的反应体系。方法:利用UV-V is-DR s和XRD对其光谱学特征进行研究。以亚甲基蓝(MB)的光催化降解反应为模型,研究Fe3 /TiO2-xNx光催化剂的催化活性及其影响因素,探讨了采用太阳光为光源降解MB的可行性。结果:x(Fe3 )为0.4%,光催化剂用量为2 g/L,初始MB浓度为1×10-6mol/L,初始pH值为8,初始H2O2浓度为6 mmol/L,采用太阳光照射4 h,MB降解率可达87%。结论:自制光催化剂能有效利用太阳光,高效降解水中亚甲基蓝。