Can oculocutaneous albinism be diagnosed prenatally?

A study of scalp and forearm skin biopsies from normally pigmented fetuses of gestational ages 16 to 28 weeks has indicated that prenatal diagnosis of albinism is a theoretical possibility. Pigment is not present in cells of the epidermis but can be found in hair follicles at the bulbous peg stage in the scalp only. Such hair follicles are present in the scalp as early as 16 weeks gestation. The findings indicate that prenatal diagnosis of albinism could be made on a scalp biopsy within the second trimester of pregnancy.     

乐安江流域人发As的分布特征研究

以江西乐安江流域受矿山活动影响的祝家村,戴村、蔡家湾村和上游参照点香田村人发为主要研究对象,应用原子荧光光昔法(AFS)测定人发中As含量,研究江西乐安江流域居民人发申As的分布.研究结果表明:1)本地区居民发As含量主要集中在0.01～0.25μg/g之间.2)主要饮食避开来自地质环境污染,位子矿区的祝家村村民发As...     

Vapor adsorption artifact in the sampling of organic aerosol: Face velocity effects

The concentration (μgC m⁻³) of aerosol organic carbon as determined by collection with quartz fiber filters was found to exhibit a significant decrease with increasing filter face velocity. A similar face velocity dependence was found for organic carbon on back-up quartz fiber filters behind either quartz fiber front filters (QQ combination) or Teflon membrane front filters (TQ combination). Additionally, the concentration of organic carbon on the back-up filter in the TQ combination was always greater than on the back-up filter in the QQ combination. The most likely explanation for these observations is the adsorption or organic vapors onto the filter medium itself. The amount of organic carbon adsorbed onto the quartz fiber front filter can be approximated by measuring the amount of organic carbon on a quartz fiber back-up filter behind a Teflon front filter with both filter combinations sampling at the same face velocity. Making the correction in such a manner removes most of the face velocity dependence inthe resultant concentrations. For 24 h sampling in Portland, Oregon, at a face velocity of 40 cm s⁻¹, the correction exceeded 50% for uncorrected organic carbon concentrations of 2 μgC m⁻³ but decreased to 15% at 16 μgC m⁻³.     

Transverse limb reduction defects after chorion villus sampling: A retrospective Cohort study

A retrospective cohort study was performed in five Italian obstetrical centres from 1984 to 1991 in order to verify the association between chorionic villus sampling (CVS) and transverse limb reduction defects (TLRDs). TLRD rates by period of gestation at CVS were calculated, and the study's results were compared with data from the general population. Of the 3430 pregnancies for which CVS was performed, 2759 had a known outcome. The overall rate for TLRDs was 1 in 1143 CVS pregnancies, four times higher than that of the general population in Italy (1 in 4458). The rate of TLRDs was 2·9/1000 for CVS performed at 9 weeks' gestation and 1·0/1000 for CVS at 10 weeks' gestation. A scalp defect was detected in a pregnancy in which CVS was performed at 10 weeks. A high proportion of pregnancies lost to follow-up and the poor quality of the data may have affected the results. Nevertheless, our results suggest an association between CVS carried out at less than 10 weeks' gestation and TLRDs which is consistent with the findings of other studies. CVS should not be prepared at less than 10 weeks' gestation until additional evidence is obtained.     

Prenatal diagnosis of monosomy 4p14→pter and trisomy 11q25→qter: clinical presentations and outcomes

We present the case of a pregnant woman with low free β-HCG in maternal serum Down syndrome screening that led to prenatal diagnosis of a fetus with 46,XY,der(4)t(4;11)(p14; q25). This chromosomal aneuploidy resulted from unbalanced segregation of a paternal balanced translocation, t(4;11)(p14;q25). Prenatal ultrasound revealed intrauterine growth restriction, cleft lip and palate, a thick nuchal fold, a single umbilical artery, and pyelectasis. Array-based comparative genomic hybridization and short tandem repeat markers further located the exact breakpoint of translocation. The woman had her pregnancy terminated at 23 weeks of gestational age. The proband had general appearance of Wolf–Hirschhorn syndrome and some unique findings, including single umbilical artery, severe immunoglobulin deficiency, scalp defect, and underlying bony defect. Our case underscores the importance of fetal karyotyping when low maternal serum free β-HCG is found. It also adds information on the fetal presentations of monosomy 4p14→pter and trisomy 11q25→qter. Copyright © 2005 John Wiley & Sons, Ltd.     

Preen gland removal increases plumage bacterial load but not that of feather-degrading bacteria

The preen gland is a holocrine sebaceous gland of the avian integument which produces an oily secretion that is spread on the plumage during preening. It has been suggested that birds may defend themselves against feather-degrading bacteria (FDB) and other potential pathogens using preen gland secretions. However, besides some in vitro studies, the in vivo bacterial inhibitory effects of the preen oil on the abundance of feather-associated bacterial species has not yet been studied in passerines. Here we tested the effect of gland removal on the abundance of FDB and other-cultivable bacterial loads (OCB) of male house sparrows (Passer domesticus). Our results did not support earlier results on in vitro antibacterial activity of preen oil against FDB since the absence of the preen gland did not significantly affect their loads related to the control birds. In contrast, we found that preen gland removal led to higher loads of OCB. This result suggests that the antimicrobial spectrum of the preen oil is broader than previously thought and that, by reducing the overall feather bacterial loads, the preen gland could help birds to protect themselves against a variety of potentially harmful bacteria.     

Shear cutting and counter shear cutting of sandwich materials

New lightweight sandwich materials challenge existing forming processes as well as following process steps. As such the manufacturing potential of shear cutting has to be evaluated. Two cutting methods are compared. Method commonly used is shear-cutting within one stroke engaged, the other one is known as counter-shear cutting, which uses two strokes.The challenges of cutting sandwich materials are variation of hole diameter within the different layers, fraying of the textiles, deformation of the hole contour and burr formation. These effects occur in conventional shear cutting as the intermediate layer and the lower sheet metal are cut by the scrap of the upper sheet instead of the cutting punch.The following methodology included shear cutting with closed cutting edge i.e. cutting of holes into five different sandwich materials. The sandwiches exemplarily represent multiple kinds of possible material designs. For instance, aluminum and steel face sheets, different thicknesses of intermediate layers and different intermediate layers materials such as integrated textile fibers have been used. Adequate cutting parameters such as die clearance and the use of a blank holder have been determined. To achieve good results a stiff machine design with good guidance and precise control of punch position was crucial.Observations of conventional shear cutting revealed the need of small cutting clearance of 4%. High burnish area is possible for the upper face sheet due to the superimposed force by the lower face sheet. The major conclusion depicted that high cutting quality of sandwich materials requires counter shear cutting. Hence, the roll-over of the lower sheet facing the intermediate layer, the burnish area at the lower sheet, good cutting quality of the fibers improve significantly and burr formation is avoided completely. Summarized this paper provides cutting parameters for sandwich materials based on experimental work.     

Prenatal diagnosis of anhidrotic ectodermal dysplasia

This paper reports on successful prenatal diagnosis of X-linked anhidrotic ectodermal dysplasia (AED) by means of light and electron microscopy on fetal skin biopsies obtained under fetoscopy. In the present family two brothers of the proband were severely affected with the full symptomatology of AED, the pregnant female and her mother revealed minor symptoms with patches of skin lacking vellus hair. Control of lesional skin of the affected family members by electron microscopy revealed no ultrastructural abnormalities. However, all biopsies lacked skin appendages including hair follicles, sebaceous glands, and sweat glands. The lack of pilosebaceous follicles can be used as a diagnostic criterion since these structures are fully developed in normal fetuses of 20 weeks whereas the development of sweat glands does not start before week 20 to 24 of fetal life. Skin biopsies were taken from various regions of the fetus at risk via fetoscopy in week 20 and processed for light and electron microscopy. All samples revealed complete absence of all skin appendages in contrast to a total of 61 non-AED fetuses. Thus positive prenatal diagnosis of AED was made and the pregnancy was terminated. Control investigations after abortion confirmed the diagnosis.     

Lobar holoprosencephaly: prenatal MR diagnosis with postnatal MR correlation

Holoprosencephaly is a congenital anomaly characterized by lack of cleavage of the prosencephalon. Although, relatively rare, it is the most common anomaly that involves both the brain and the face. Prenatal diagnosis of this anomaly using ultrasonography, particularly of the less severe forms, is difficult. Magnetic resonance imaging has recently become an important complement to US in prenatal diagnosis of CNS anomalies. We herein report a patient in whom, at 23 weeks of gestation, US suggested agenesis of the corpus callosum and in whom, at 24 weeks of gestation, MRI correctly diagnosed lobar holoprosencephaly, which was confirmed by a postnatal MRI at 3 weeks of age. Copyright © 2005 John Wiley & Sons, Ltd.     

小屯矿14643综采面煤层自燃综合防治技术研究

本文针对小屯矿14643综采面煤层自燃的特性,结合标志气体指标色谱分析及煤自燃倾向性鉴定预测预报体系,采用喷洒阻化剂、压注凝胶阻燃剂及注氮气的防灭火技术,形成工作面自燃火灾的综合防治技术体系,成功地对小屯矿14643综采面煤层自燃火灾进行了治理,取得了明显的效果.该研究可为煤矿开采煤层自燃的综合防治提供技术支撑.     

DNA-based carrier detection and prenatal diagnosis of tyrosinase-negative oculocutaneous albinism (OCA1A)

We describe molecular prenatal diagnosis and carrier detection of tyrosinase-negative oculocutaneous albinism (OCA1A) in two families. In one family, we carried out DNA-based prenatal diagnosis of OCA1A. In the other family, mutation analysis and carrier detection obviated the need for prenatal diagnosis. Molecular analysis is safer and probably more accurate than fetoscopy and fetal scalp biopsy, and should become the method of first choice for prenatal diagnosis of OCA1.     

养鸡项目对环境空气的影响分析研究

养殖场恶臭来自肉鸡粪便、污水、垫料、饲料等腐败分解,肉鸡的新鲜粪便、消化道排出的气体,皮脂腺和汗腺的分泌物,粘附在体表的污物等,呼出气中的CO2等也会散发出鸡特有的难闻气味。但养鸡场恶臭主要来源是鸡粪便排出体外之后的腐败分解。影响鸡场恶臭产生的主要因素是清粪方式、管理水平、粪便和污水的无害化处理程度。同时,也与场址规划和布局、畜舍设计、畜舍通风等有关。鸡舍内的有害气体主要来自鸡群的呼吸、排泄、饲料等有机成分分解。有害气体主要有氨气、硫化氢、一氧化碳、二氧化碳、甲烷、臭粪素等。其中对环境危害最大的恶臭物质是NH3和H2S。分析养鸡项目对环境空气的影响及所采取的污染防治措施。     

膜生物反应器中膜污染研究进展

膜生物反应器是近年新发展起来的高效废水处理工艺。本文综述了国内外对膜污染机理研究的最新成果 ,介绍了相应的解决措施 ,展望了今后的发展前景。     

Prenatal ultrasound diagnosis of frontonasal dysplasia

We report a case of prenatal ultrasound diagnosis of frontonasal dysplasia. This represents a very rare disorder involving the face (hypertelorism, median cleft lip, absence of the nasal tip) and often the central nervous system (CNS) (cranium bifidum occultum, ethmoidal cephalocele, agenesis of the corpus callosum). Although several of the typical anomalies are diagnosable by ultrasound in utero (hypertelorism, median cleft lip, anterior cephalocele), very few cases have been reported prenatally, the present being only the third. In the present case, hemimegalencephaly is first reported among the anomalies possibly associated with frontonasal dysplasia. The diagnosis was made at 22 weeks' gestation and was confirmed by necropsy following termination of pregnancy. Copyright © 2002 John Wiley & Sons, Ltd.     

水土保持工作中存在的问题及对策

我国一直以来就是一个水土流失大国,治水保土工作一直备受重视。当前在我国经济快速发展,环境问题日益突出的情况下,合理开发和保护水资源,充分做好水土保持工作已经是各级政府部门和社会各界面临的一个重要课题。     

Cleaner production in New Zealand: taking stock

New Zealand has seen a significant change in attitude and behaviour toward sustainable business practices since the late 1980s when the introduction of cleaner production marked the beginning of a change in the way the relationship between business and the environment was perceived. The context of this change is important. New Zealand is unique in terms of its relative geographic isolation and as a consequence human settlers encountered a unique ecosystem, dominated by avian species and without mammalian predators. Subsequent anthropogenic activity has seriously impacted New Zealand's biodiversity and sustainability is seen by many as a way of restoring, or at least conserving the remnant of that unique ecosystem. The country's natural environment and resources, the shape of business and the health of the economy all colour the way and rate at which sustainability is adopted. This paper charts that change and provides a perspective on relevant policy, research and intervention initiatives over the last 15 years or so and discusses the challenges that face New Zealand in a global market.     

Social dilemmas,policy instruments,and climate adaptation measures: the case of green roofs

Green roofs contribute to both climate change adaptation and mitigation. Promoting green roofs is thus a key element in urban strategies to address climate change. How to actually promote green roofs, however, has so far proven elusive: attempts to link specific policy instruments to a more or less successful diffusion of green roofs have been few and far between. The present paper relies on institutional economics to advance the present understanding of the link between policy instruments and green roofs. It argues that different green roofs are confronted with different social dilemmas, and thus require different policy instruments. Specifically, small green roofs face a free-rider problem, which is best addressed through regulations and incentives. Large green roofs face instead a collective action problem, which is best addressed through communications and network-building. This perspective is tested empirically through a comparative analysis of 18 global cities on the forefront in the promotion of green roofs. The policy instruments observed in these cities match with the theoretical expectations laid down in the paper. Implications emerge for both policy and research.

     

Das motorische Intentionspotential

Autocorrelation of the EEG was used to registrate a potential from the intact human scalp during intended, but not executed movements (dorsalflexion of the right hallux, imaginated in equal time intervals). This "Motor Intention Potential" (MIP) is a possible electrophysiological sign of the otherwise purely introspectively experienced intention of a voluntary movement and the cortex of the frontal lobes is suspected to be its origin. The average maximum amplitude height is 6 microV, and the potential shows a continuous decrease from the frontal to occipital region. The duration of MIP is in the range of seconds. Methodological questions are discussed, and the MIP is differentiated from other event-, movement- and imagination-related potentials. An attempt is made to place the motor intention potential in the context of existing movement theories.     

持续创新，打造我国生态环境科技2.0

生态环境科技为我国经济发展和生态保护提供重要的技术支撑,新时期下以习近平生态文明思想为指导,回顾我国生态环境科技进步历程、展望发展方向,对以生态环境科技创新引领带动全社会产业绿色可持续发展具有重大的理论和实践指导意义.首先,回顾我国生态环境科技发展的3个主要阶段:开拓期（1972—1990年）,初步建成环境总量容量的科技体系;发展期（1991—2011年）,创新了流域区域污染治理的理论和技术;新时期（2012年至今）,打造精准治污、系统治理的科技支撑体系.其次,系统梳理总结我国生态环境科技在重点流域区域水污染防治、大气污染治理、土壤污染调查与风险管控及修复、固体废物处置与资源化利用、生态保护修复与监管、环境标准基准建设以及环保产业创新能力7个方面取得的重大成果、为污染防治攻坚战提供的有力支撑.最后,分析我国生态环境科技发展面临的需求与挑战,提出我国生态环境科技2.0时代的治污理念及发展对策:①坚持四个“面向”.一是面向世界科技前沿,夯实生态环境科研基础;二是面向经济主战场,促进生态环境科技成果转化;三是面向国家重大需求,开展生态环境领域集智攻关;四是面向人民生命健康,牢牢把握“环保科技的人民性”.②协同三个系统.一是自然系统,从根源上解决生态环境问题,标本兼治,守住自然系统生态安全边界;二是生产系统,强化科技创新驱动,促进生产系统的绿色循环,形成经济增长的绿色新动能;三是生活系统,开展绿色产品、绿色消费研究创新,推动绿色生活转型.③实现“五个创新”.在绿色发展模式、环境治理理念、环境科研方法、多技术融合以及体制机制上实现多元创新,打造新时期下全面发展的生态环境科技2.0时代.      

The obstetrician's view: ethical and societal implications of non-invasive prenatal diagnosis

We believe non-invasive prenatal diagnosis is about to have a massive impact on the way fetal medicine is practised. There will be many great advantages and improvements, but the technology also has the potential to be used for non-medical reasons such as sex selection and paternity testing. We discuss some of the issues that may face obstetricians in the future as a result of this emerging technology. Copyright © 2006 John Wiley & Sons, Ltd.