Effects of electromagnetic fields produced by radiotelevision broadcasting stations on the immune system of women.

The object of this study was to investigate the immune system of 19 women with a mean age of 35 years, for at least 2 years (mean = 13 years) exposed to electromagnetic fields (ELMFs) induced by radiotelevision broadcasting stations in their residential area. In September 1999, the ELMFs (with range 500 KHz-3 GHz) in the balconies of the homes of the women were (mean +/- S.D.) 4.3 +/- 1.4 V/m. Forty-seven women of similar age, smoking habits and atopy composed the control group, with a nearby resident ELMF exposure of < 1.8 V/m. Blood lead and urinary trans-trans muconic acid (a metabolite of benzene), markers of exposure to urban traffic, were higher in the control women. The ELMF exposed group showed a statistically significant reduction of blood NK CD16+-CD56+, cytotoxic CD3(-)-CD8+, B and NK activated CD3(-)-HLA-DR+ and CD3(-)-CD25+ lymphocytes. 'In vitro' production of IL-2 and interferon-gamma (INF-gamma) by peripheral blood mononuclear cells (PBMC) of the ELMF exposed group, incubated either with or without phytohaemoagglutinin (PHA), was significantly lower; the 'in vitro' production of IL-2 was significantly correlated with blood CD16+-CD56+ lymphocytes. The stimulation index (S.I.) of blastogenesis (ratio between cell proliferation with and without PHA) of PBMC of ELMF exposed women was lower than that of the control subjects. The S.I. of blastogenesis of the ELMF exposed group (but not blood NK lymphocytes and the 'in vitro' production of IL-2 and INF-gamma by PBMC) was significantly correlated with the ELMF levels. Blood lead and urinary trans-trans muconic acid were barely correlated with immune parameters: the urinary metabolite of benzene of the control group was only correlated with CD16+-CD56+ cells indicating a slight effect of traffic on the immune system. In conclusion, this study demonstrates that high frequency ELMFs reduce cytotoxic activity in the peripheral blood of women without a dose-response effect.     

短碳纤维在石墨低频电磁屏蔽混凝土中的应用研究

介绍了分别掺杂短碳纤维和石墨的电磁屏蔽混凝土的制备,研究了短碳纤维和石墨的含量对混凝土低频电磁屏蔽效能的影响,最后分析了短碳纤维的加入对石墨混凝土电磁屏蔽性能的影响机理,为将来设计高性能低频电磁屏蔽混凝土提供了依据。     

有限域子集上的Hermite判别法及推广

利用有限生成代数的语言重述关于置换多项式的经典的Hermite判别法,并将其推广到有限域的子集上,另外也推广了其他一些关于有限域上置换多项式的结果,并给出了一定条件下相关函数的值集大小估计.最后,给出主要结果在有限域上n阶单位根群中的应用实例,并得到了一些有趣的结果.     

健康教育频次对绝经后女性骨质疏松症患者治疗效果的影响

目的 评估健康教育频次对绝经后女性骨质疏松症（osteoporosis，OP）患者近期治疗效果的影响。方法 绝经后女性OP患者共373例，按1年内自愿参加健康教育的频次不同分为A组（未参加健康教育）83例，B组（参加1~4次健康教育）117例，C组（参加5~8次健康教育）101例及D组（参加9~12次健康教育）72例。所有患者均进行规范抗骨质疏松治疗，同时鼓励患者自愿参加每月1次的健康教育活动，随访观察1年。分别采用骨质疏松知识问卷（osteoporosis knowledge tests，OKT）、健康行为问卷及骨密度检测对4组患者抗骨质疏松治疗效果进行评价。结果 （1）与治疗前相比，1年中各组患者骨密度值均有显著提高（P<0.05），B组、C组、D组患者OKT评分均有显著提高（P<0.05），健康行为均有显著改善（P<0.05）；（2）治疗后与A组（10.50±3.58）分相比，B组（15.70±3.10）分、C组（19.03±3.03）分、D组（20.13±3.05）分患者的OKT评分均有显著提高，差异有统计学意义（P<0.05），健康行为均有显著改善（P<0.05），但C组与D组间OKT评分差异无统计学意义（P>0.05）。（3）治疗后B组、C组、D组患者骨密度值增高显著高于A组，差异有统计学意义（P<0.05），但C组与D组间骨密度值增高差异无统计学意义（P>0.05）。结论 在规范抗骨质疏松治疗的同时，每两个月对患者进行一次健康教育能显著提高患者对骨质疏松症的认知水平，帮助患者养成健康的行为习惯，提高OP的治疗效果。     

Effects of co-exposure to extremely low frequency (50 Hz) magnetic fields and xenobiotics determined in vitro by the alkaline comet assay

In the present study, we used human peripheral blood leukocytes from 4 different donors, to investigate in vitro the possible genotoxic and/or co-genotoxic activity of extremely low frequency magnetic fields (ELF-MF) at 3 mT intensity. Two model mutagens were used to study the possible interaction between ELF-MF and xenobiotics: N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and 4-nitroquinoline N-oxide (4NQO). Primary DNA damage was evaluated by the alkaline single-cell microgel-electrophoresis ("comet") assay. Control cells (leukocytes not exposed to ELF-MF, nor treated with genotoxins) from the different blood donors showed a comparable level of basal DNA damage, whereas the contribution of individual susceptibility toward ELF-MF and the tested genotoxic compounds led to differences in the extent of DNA damage observed following exposure to the genotoxins, both in the presence and in the absence of an applied ELF-MF. A 3 mT ELF-MF alone was unable to cause direct primary DNA damage. In leukocytes exposed to ELF-MF and genotoxins, the extent of MNNG-induced DNA damage increased with exposure duration compared to sham-exposed cells. The opposite was observed in cells treated with 4NQO. In this case the extent of 4NQO-induced DNA damage was somewhat reduced in leukocytes exposed to ELF-MF compared to sham-exposed cells. Moreover, in cells exposed to ELF-MF an increased concentration of GSH was always observed, compared to sham-exposed cells. Since following GSH conjugation the genotoxic pattern of MNNG and 4NQO is quite different, an influence of ELF-MF on the activity of the enzyme involved in the synthesis of GSH leading to different activation/deactivation of the model mutagens used was hypothesized to explain the different trends observed in MNNG and 4NQO genotoxic activity in the presence of an applied ELF-MF. The possibility that ELF-MF might interfere with the genotoxic activity of xenobiotics has important implications, since human populations are likely to be exposed to a variety of genotoxic agents concomitantly with exposure to this type of physical agent.     

IGF-1在妊娠期糖尿病胎盘组织中的表达及其对新生儿T淋巴细胞亚群的影响

目的分析胰岛素样生长因子-1(IGF-1)在妊娠期糖尿病(GDM)胎盘组织中的表达及其对新生儿T淋巴细胞亚群的影响。方法选取本院GDM患者(研究组)和同期健康孕妇(对照组)各40例。两组孕妇均于胎儿、胎盘分娩后于胎盘中央带取材,行常规HE染色和IGF-1抗免疫组织化学染色,比较两组孕妇胎盘组织中IGF-1表达强度和分娩的新生儿T淋巴细胞亚群指标的差异,并进行相关性分析。结果研究组IGF-1表达强于对照组。IGF-1主要存在于滋养层上皮细胞胞浆和少数血管内皮细胞中。与对照组孕妇新生儿比较,研究组孕妇新生儿CD_3~+、CD_4~+、CD_4~+/CD_8~+显著较低,CD_8~+显著较高。相关性分析结果显示孕妇胎盘组织中IGF-1表达强度与CD_3~+、CD_4~+、CD_4~+/CD_8~+呈正相关,与CD_8~+呈负相关。结论 GDM胎盘组织中的IGF-1表达水平较健康孕妇高,GDM胎盘组织中的高IGF-1表达可显著影响新生儿T淋巴细胞亚群,导致新生儿免疫功能低下。     

低温低浊期生产废水直接回用试验研究

通过混凝试验研究了低温低浊期水厂生产废水直接回用对混凝效果和沉后水水质的影响。结果表明,回用生产废水可明显改善混凝效果;当生产废水回用比例低于10%时,不但可以有效改善混凝效果,而且不会增加消毒剂耗用量、出水铝含量及UV254含量。     

椎管内外哑铃状神经鞘瘤的临床特点及治疗方式探讨

目的:探讨椎管内外哑铃状神经鞘瘤的临床特点及治疗方式,为临床治疗提供依据。方法:回顾性分析2012年1月-2017年6月广元市中心医院神经外科收治的30例椎管内外哑铃状神经鞘瘤的临床资料。手术均采用侧卧位后正中入路显微镜下病变切除术,其中行单侧钉棒系统固定13例,双侧钉棒系统固定15例,椎板部分切除未行内固定2例。术中常规采用神经电生理监测,避免神经功能损伤,同时将穿过肿瘤的部分神经切除。结果:30例椎管内外哑铃状肿瘤,SimpsonⅠ级和Ⅱ级切除9例,Ⅳ级切除1例。术后患者痊愈28例,好转2例,术后病理结果显示WHOⅠ级神经鞘瘤27例(其中4例伴有囊肿及出血),神经纤维瘤3例。随访1～5年,未见复发,所有患者均未行放疗及化疗。结论:椎管内外哑铃状神经鞘瘤在脊柱并不少见,该肿瘤通常都由神经根发出,临床由椎管内波及椎管外,病变椎间孔扩大部分,部分波及椎体部分,如椎体波及超过1/3及同侧上下关节突影响较大的需行植骨融合及钉棒系统固定,避免术后脊柱变形,因此术前应全面检查需行MRI、CT、X线等全面检查,术前做好准备,在保护神经完整及功能安全情况下,尽量如肿瘤切除后易导致脊柱不稳定,术中需同时行椎体融合及钉棒系统固定,防止术后脊柱畸形,术中争取全切除肿瘤,切除程度对预后是否复发影响较大。     

某博物馆中庭及相邻区域热环境数值模拟

有透明围护结构的中庭具有"温室效应"和上部空间热量堆积的特点,特别是竖直方向上有明显的温度梯度。以某博物馆的中庭及与其相通的走廊为研究对象,利用CFD软件模拟了夏季3种工况、冬季2种工况下的热环境,并对夏季3种工况进行了能耗分析。建议在夏季,将中庭及与其相连的走廊作为一个整体进行空调设计,上层空调机组承担较多的负荷,下层空调机组承担较少的负荷;在冬季,中庭地面设置地板辐射供暖。     

Energy, economic and environmental (3E) analysis of a micro gas turbine employed for on-site combined heat and power production

This paper studies the optimization of micro turbine application to meet the electrical, heating and cooling loads of a building by energy, economics and environmental analysis. In this study following three cases are considered: 1: A simple micro gas turbine to meet the electrical power of the building. 2: A simple micro gas turbine to meet the electrical power of the building as well as the power required by heat pump and mechanical refrigerator needed for heating, cooling and domestic hot water (DHW) systems. 3: A CHP micro gas turbine to meet the electrical power of the building as well as part of the power required by heat pump and mechanical refrigerator needed for heating, cooling and DHW systems. The remaining part of the power for heat pump and mechanical refrigerator is provided by the exhaust gases.The research shows that the initial investment is a considerable portion of electricity cost. For an annual interest rate of 10% this portion ranges from 31 to 40% depending on system design configurations, and the lower interest rates results in the smaller portions. It is also concluded that the number of turbine units and electricity cost are highly depended on electricity consumption management.     

Young men,public space and the production of fear in downtown Adelaide

This article considers the interconnection between certain spaces and ‘fear-inducing’ masculine gender performances. Particularly, it looks at the night-time use of downtown spaces by young men, reconsidering existing theory and developing new methodology to examine how and why young men use specific areas to engage in aggressive, hyper-masculine gender performances. By considering issues of space and gender alongside use of new media, this article suggests a method of investigating the production of fear by reviewing the cultural and spatial literacies of those who reputedly produce it.     

盐岩储库腔底堆积物空隙体积试验与计算

受建库盐层本身地质特点影响,造腔结束后,底部一般会堆积大量不溶物。堆积物的存在既浪费了有效库容体积,又为整体建库施工带来了诸多不利因素。为科学评价该堆积物并进行有效处理或转变利用以增大库容体积,对其分布特征及堆积空隙体积进行了研究。通过室内溶腔实验获取了堆积不溶物样品,采用筛分法实验测定了其颗粒分布,并根据分形分布理论对其粒度分布特征进行了分析,进而基于可压缩堆积模型对堆积空隙体积进行了数值及模型研究。应用实例进行计算并与现场数据进行了对比评价验证,结果表明,在双对数坐标系下,腔底堆积物颗粒尺寸与累积数量呈线性相关,即其粒度分布可用分形分布函数进行表征,且分形维数作为分布特征参量能较好地描述颗粒均匀程度与集中性。     

博物馆中自然光与人工光的光照平衡性研究

通过对博物馆视觉环境的策略制定,对其展陈空间的自然光和人工光的平衡关系进行了研究,分析了人工光的视觉功用,以及采光设计和自然光控制的要求,以指导博物馆光环境的设计。     

Technical feasibility and economic viability of a grid-connected PV installation for low cost electricity production

This paper describes the installation, technical characteristics, operation and economic evaluation of one of the largest grid-connected photovoltaic (PV) systems installed in Greece, and in particular in the island of Paros in the Aegean Sea. Attention is drawn on the impact of PV utilization on the ecological tourism, which is growing very fast in Greece. Also, several issues are considered when assessing the value of PV electricity. The value of PV has been examined from various perspective consumer, utility and environmental and for central and decentralized PV systems in conjunction with the benefits for all the involved parties, i.e. the owners, operators, users, tourists, investors, renewable system industry and local authorities.     

Association of toxic and essential metals with atopy markers and ventilatory lung function in women and men

The association of age, smoking, alcohol, superoxide dismutase (SOD), glutathione peroxidase (GPx), blood lead (BPb) and cadmium (BCd) levels, and serum levels of copper (SCu), zinc (SZn) and selenium (SSe) with atopic status and ventilatory function was examined in the groups of 166 women and 50 men with no occupational exposure to metals or other xenobiotics. Markers of atopy included serum total IgE, skin prick test (SPT) to common inhalatory allergens, non-specific nasal reactivity (NNR) and non-specific bronchial reactivity (NBR). Parameters of ventilatory function included forced vital capacity (FVC) and forced expiratory volume in the first second (FEV(1)). Significantly higher BPb, SZn, IgE and prevalence of positive SPT, and lower SCu and NNR was found in men than in women. Fifteen women taking female sex hormones (HT) had significantly higher SCu than women without HT. Regression models showed significant inverse associations between IgE and SCu (P=0.021) and NNR and SCu (P=0.044) in women. When excluding women with HT, the association of SCu and total IgE became of borderline significance (P=0.051), association between SCu and NNR disappeared, and significant positive association between total IgE and BPb emerged (P=0.046). In men, significant inverse association was found between positive SPT and SSe, and between NBR and SSe. A decrease in FVC% and FEV(1)% was associated with an increase in smoking intensity (P<0.001) and a decrease in SZn (P=0.043 and P=0.053, respectively). These results were observed at the levels of the metals comparable to those in general populations worldwide. The observed differences between men and women may partly be explained by different levels of relevant toxic and essential metals, and their combination. The role of female HT in associations of atopy markers and SCu should be further investigated.     

海面波浪谱对深海低频环境噪声的影响

提出了一种适用于深海低频环境噪声的波浪谱,通过声压谱和波浪谱的理论关系,分析了深海低频噪声在百赫兹以下的谱特征,解释了不同频段噪声谱的主要产生机理。将深海传播条件下海面波浪谱与海面风速相结合,利用波浪发声理论得到一种低频海洋环境噪声理论表示方法。仿真结果表明,波浪谱决定着辐射噪声谱的强度和斜率,本模型得到的理论噪声谱可以对低频海洋环境噪声进行预报。2016年的深海实验观测数据分析显示,统计的环境噪声谱级在1 Hz至100 Hz频段范围内大于70 dB,并且噪声谱在低频段呈倒"N"型,在3~4 Hz处为噪声谱的谷值,噪声级为70 dB,在50 Hz处为噪声谱的峰值,噪声级为92 dB,通过理论计算和实验对比,相关系数为0.95,理论结果和实验测量对比结果符合较好。     

Plan and survey of an underground art museum in Japan, using a large-scale rock cavern

The Takayama Festival Float Art Museum, which is located in Takayama City in the Hida District of Gifu Prefecture, in central Japan, is the first large-scale rock cavern for public use in Japan. This paper outlines the project rationale, structural design, and construction of the museum.     

慢性应激对小鼠空间学习记忆的影响及脑内Wnt3a的表达

目的:研究慢性应激对小鼠空间学习记忆的影响及机制。方法 :慢性应激模型的建立采用的是持续21天的7种不同应激方式,通过Morris水迷宫实验检测小鼠的空间学习记忆能力,免疫组织化学方法检验小鼠脑内各脑区wnt3a的表达。结果:慢性应激组小鼠与对照组小鼠相比,在定位航行试验中,小鼠寻找平台的逃避潜伏期明显提高(P<0.05),空间搜索实验中,应激组小鼠在目标象限的游泳时间明显减少(P<0.05)。在小鼠脑内PFC区wnt3a表达显著减少(P<0.01)。结论 :慢性应激对小鼠空间学习记忆的能力具有损伤作用,这与wnt3a在脑内的表达关系密切。     

Effects of frequency and grouted length on the behavior of guided ultrasonic waves in rock bolts

Experiments were conducted to study the behavior of guided waves in free and grouted rock bolts. Ultrasonic waves with frequencies from 25 to 100 kHz were used as excitation inputs. Tests were first conducted on free bolts to help understand the behavior of guided waves in non-grouted bolts. The effects of wave frequency and grouted length on the group velocity and attenuation of the guided ultrasonic waves were then evaluated. The test results indicated clear but different trends for the group velocity in the free and the grouted bolts. The attenuation in free bolts was not affected by bolt length and frequency. However, in grouted bolts it increased with frequency and grouted length. It was also found that the two main sources of attenuation are the setup energy loss, which has a fixed quantity for a specific type of test setup, and the dispersive and spreading energy loss which varies with frequency and bolt length.