噪声损害鉴定方法和程序探讨

目前噪声污染问题正成为人民群众日益关心的突出问题,对于解决噪声污染引起的各种纠纷和诉讼,开展损害鉴定是重要手段,而目前国家并未出台噪声损害鉴定的相关技术导则,文章结合噪声相关法律法规、技术标准及实践经验,总结开展噪声损害鉴定的方法和程序及注意事项,为相关从业人员提供参考.     

建设项目竣工环境保护验收监测的工作程序和问题思考

简要介绍了建设项目竣工环境保护验收监测的工作程序,并结合工作实际,对验收监测中遇到的几个问题进行阐述,以利于建设项目竣工验收。     

Invasive diagnostic procedures in twin pregnancies

The rising rate of multiple pregnancies and its association with advanced maternal age has expanded the need for prenatal diagnosis in twins and higher order gestations. The complexity of the invasive diagnostic procedures and the risk of loss of an unaffected twin raise significant clinical, technical and ethical issues. In this review we discuss the specific issues of early scanning, counseling and determination of chorionicity prior to invasive procedures in twins. We present the available data describing the risk associated with these procedures in twins and compare data of fetal loss rate from different studies. We also discuss the issues of fetal blood sampling and late karyotyping in twin pregnancies. Copyright © 2005 John Wiley & Sons, Ltd.     

Preface Streamlining JI and CDM accounting procedures through a multi-project approach

Mitigation and Adaptation Strategies for Global Change -     

Criteria and procedures for evaluating the quality of fish populations in reservoirs

Routine assessments of sport fish populations are necessary for managers to determine whether populations are meeting objectives. An effective assessment technique should entail rating parameters that are measurements of, or are influenced by the three rate functions of recruitment, growth, and mortality. It will enable managers to determine which rate functions may be preventing a population from achieving stated objectives and help them determine if additional management or research efforts are needed. The first requirement of an effective assessment technique is a standard sampling method that captures all sizes of fish that are present in the population. The sampling method should detect changes in population density and size structure, which will then be reflected in sample length frequencies. Other important criteria are the selection of appropriate parameters from the sample data and the setting of objectives for those parameters. An ideal assessment should include parameters that depict recruitment levels, adult density, growth rate, age structure, and size structure. The parameter value should be easy to calculate from sample data. Use of an assessment for white crappies in Missouri’s large reservoirs showed that growth was generally good, but mortality was high. Subsequent research indicated that angler exploitation was the cause of the high mortality, which led to the successful implementation of restrictive harvest regulations.     

Aspects of biopsy procedures prior to preimplantation genetic diagnosis

Today, preimplantation genetic diagnosis (PGD) is offered in over 40 centres worldwide for an expanded range of genetic defects causing disease. This very early form of prenatal diagnosis involves the detection of affected embryos by fluorescent in situ hybridization (FISH) (sex determination or chromosomal defects) or by polymerase chain reaction (PCR) (monogenic diseases) prior to implantation. Genetic analysis of the embryos involves the removal of some cellular mass from the embryos (one or two blastomeres at cleavage-stage or some extra-embryonic trophectoderm cells at the blastocyst stage) by means of an embryo biopsy procedure. Genetic analysis can also be performed preconceptionally by removal of the first polar body. However, additional information is then often gained by removal of the second polar body and/or a blastomere from the embryo. Removal of polar bodies or cellular material from embryos requires an opening in the zona pellucida, which can be created in a mechanical way (partial zona dissection) or chemical way (acidic Tyrode's solution). However, the more recent introduction of laser technology has facilitated this step enormously. Different biopsy procedures at different preimplantation stages are reviewed here, including their pros and cons and their clinical applications. The following aspects will also be discussed: safety of zona drilling by laser, use of Ca²⁺/Mg²⁺-free medium for decompaction, and removal of one or two cells from cleavage-stage embryos. Copyright © 2001 John Wiley & Sons, Ltd.     

Implementing sustainable laundering procedures for textiles in a commercial laundry and thus decreasing wastewater burden

This paper presents a research on how to optimize a laundering program to reduce wastewater burden thus achieving a more sustainable laundering procedure. A green surgical textiles program was investigated and the first step of optimization was performed based on the results of measuring certain parameters in the water taken from individual chambers. The wastewater parameters were reduced after optimization of the program although effluent treatment plants for water reuse remain necessary. An experimental laundering procedure with a high dosage of sodium hypochlorite was also conducted in order to observe a correlation between measured values of active chlorine and conductivity. As an approximate correlation was found this could result in the possibility of incorporating a sensor in the washing machine measuring online the conductivity with the possibility of regulating the dosage of sodium hypochlorite and thus preventing overdosing, which increases the damages of the laundered textiles and the burden of wastewater.     

Overview of the impact of noninvasive prenatal testing on diagnostic procedures

Noninvasive prenatal testing (NIPT) has had a profound influence in the field of prenatal diagnosis since the 1997 discovery of cell-free fetal DNA in maternal blood. Research has progressed rapidly, with clinical data supporting laboratory studies showing that NIPT is highly sensitive and specific for fetal aneuploidy, resulting in marked uptake in the high-risk patient population. The superior accuracy of NIPT compared with conventional screening methods has led to significant decreases in the number of invasive diagnostic procedures, in addition to a concomitant decrease in the number of procedure-related fetal losses. Yet, NIPT has been described as a ‘disruptive innovation’ due to the considerable changes the technology has commanded on current prenatal screening and diagnostic practices. This review summarizes both institutional and global experience with NIPT uptake, its effect on reducing diagnostic invasive procedures, and the unique challenges that reduced procedural volume may have on physician and trainee proficiency, cytogenetic laboratories, and neonatal outcome. © 2015 John Wiley & Sons, Ltd.     

Monitoring impact of mefenacet treatment on soil microbial communities by PCR-DGGE fingerprinting and conventional testing procedures

The effect of acetanilide herbicide mefenacet on soil microbial communities was studied using paddy soil samples with different short-term treatments. The culturable bacteria （plate counts）, dehydrogenase activity and changes in community structure （denaturing gradient gel electrophoresis （DGGE） analysis） were used for biological community assessments. Mefenacet was a significant stimulus to cultural aerobic bacteria and dehydrogenase activity while Sphingobacterium multivorum Y1, a bacterium efficiently degrading the mefenacet, only induced the increasing colony-forming unit （CFU） of bacteria but little effect on dehydrogenase activity during the whole experiment. The degree of similarity between the 16S rDNA profiles of the communities was quantified by numerically analyzing the DGGE band patterns. Similarity dendrograms showed that the microbial community structures of the mefenacet-treated and non-treated soils were not significantly different. But supplement of S. multivorum Y1 could increase the diversity of the microbial community in the mefenacet-polluted paddy soil. This work is a new attempt to apply the S. multivorum Y1 for remediation of the mefenacet-polluted environments.     

Changes in maternal serum alpha-fetoprotein levels associated with intrauterine genetic diagnostic procedures

The amount of fetal—maternal transfusion during invasive intrauterine diagnostic instrumentation was determined by measuring the increase in maternal serum alpha-fetoprotein (Δ AFP) caused by the procedure. Fetal liver biopsy or fetoscopy for purposes other than blood sampling caused a mean Δ AFP of 11.4 ng/ml and 34.2 ng/ml, respectively. Fetoscopy with fetal blood sampling produced a mean Δ AFP of 211.8 ng/ml, while fetoscopy followed by placentesis caused a mean Δ AFP of 462.8 ng/ml (representing a 1.07 ml fetal—maternal transfusion). Although this magnitude of fetal—maternal transfusion is an acceptable risk for the fetus, it is a sufficient transfusion to cause blood cell antigen sensitization.     

Evaluating the blank contamination and recovery of sample pretreatment procedures for analyzing organophosphorus flame retardants in waters

Organophosphate esters (OPEs), used as flame retardants and plasticizers, are widely present in environmental waters. Development of accurate determination methods for trace OPEs in water is urgent for understanding the fate and risk of this class of emerging pollutants. However, the wide use of OPEs in experimental materials results in blank interference, which influences the accuracy of analytical results. In the present work, blank contamination and recovery of pretreatment procedures for analysis of OPEs in water samples were systematically examined for the first time. Blank contaminations were observed in filtration membranes, glass bottles, solid phase extraction cartridges, and nitrogen blowing instruments. These contaminations could be as high as 6.4–64 ng/L per treatment. Different kinds of membranes were compared in terms of contamination levels left after common glassware cleaning, and a special wash procedure was proposed to eliminate the contamination from membranes. Meanwhile, adsorption of highly hydrophobic OPEs on the inside wall of glass bottles was found to be 42.4%–86.1%, which was the primary cause of low recoveries and was significantly reduced by an additional washing step with acetonitrile. This work is expected to provide guidelines for the establishment of analysis methods for OPEs in aqueous samples.     

A comparison of the compositional differences between humic fractions isolated by the IHSS and exhaustive extraction procedures

Humic substances (HSs), consisting, on the basis of solubilities in aqueous acid and basic media, of humic acids (HAs), fulvic acids (FAs), and humin (Hu), are the major components of soil organic matter (SOM). Most studies of soil/natural organic matter (SOM/NOM) have been carried out on extracts of soils in dilute sodium hydroxide solutions, the solvent used to extract the Standards of the International Humic Substances Society (IHSS). However, Hu, the major component in the classical definition of HSs, is insoluble in aqueous base and is not isolated by the traditional IHSS method. Recently, a sequential exhaustive extraction (SEE) process has been shown to be capable of isolating and separating the major components of the classically defined HSs from the soils of the temperate and tropical regions. The SEE system was used in the present study to isolate the HA/FA and Hu fractions from a subtropical volcanic Taiwanese soil. Chemical and compositional properties of these extracts were then compared with similarly obtained isolates from soils from the different climatic regions. Increases in the aliphatic relative to aromatic carbon contents were observed for both the HA and FA fractions when the pH values of the extraction media were increased. HAs and FAs isolated using the SEE method have spectroscopic profiles similar to those from the IHSS isolate; however, the cumulative extraction efficiency (%) of the SEE method (65 %) for the volcanic soil was much higher than for the traditional IHSS method (33 %). When the residual volcanic soil, following extractions once, three, and eight times with 0.1 M NaOH were then extracted with dimethyl sulphoxide (DMSO) plus concentrated sulphuric acid (the final solvent in the SEE sequence) it was seen that the content of crystalline polymethylene hydrocarbon (33 ppm ¹³C-NMR resonance in the Hu (or DMSO/acid)) extract increased relative to the amorphous methylene (30 ppm). That highlights the difficulty in dissolving the more highly ordered hydrocarbon structures that would be expected to have closer associations with the mineral colloids. Although the SEE procedure isolated all of the HAs and FAs from the Yangmingshan soil, extractability of the Hu from the volcanic soil in the DMSO/acid solvent was low (21 %), and contrasted with the much higher yields from temperate and tropical regions. The decreased Hu extraction may arise from its associations with the extensive iron and aluminium hydroxide mineral colloids in the soil. The Hu from this sub-tropical soil was different from the Hus isolated from other soil types, indicating the need to isolate and characterise these recalcitrant organic material in order to understand the organic carbon components in soils in greater detail. Such results would indicate that more attention should be given to mineral colloids in soils, and to the organo/mineral associations that will have an important role in the stabilities of OM in the soil environment.     

Factors associated with multiple-pass procedures during chorionic villus sampling: A video analysis

Multiple placental passes during chorionic villus sampling (CVS) increase the risk of fetal loss; however, specific factors that predispose to repeat aspiration have not been delineated. To identify anatomic and technical variables associated with multiple-pass procedures, a detailed review of 205 videotaped CVS procedures (single pass = 163; multiple pass = 42) was performed, blinded to pregnancy outcome. The route of sampling did not influence the need for multiple aspiration attempts (transabdominal—30/ 135; transcervical—12/70), nor was placental location alone discriminatory. However, the combination of a posterior placenta and uterine retroversion was observed more frequently in the multiple-pass cohort (8/42 vs. 9/163; p<0.05). In transabdominal cases, suboptimal needle placement (e.g., perpendicular to the placental long axis) was more common in the initial aspiration of a multiple-pass procedure (21/30 vs. 38/105;p<0.01), while limited penetration of the catheter tip (e.g., just inside the placental edge) characterized a majority of multiple-pass cases in the transcervical subset (7/12 vs. 3/58; p<0.0001). A case-control cohort was constructed to evaluate the impact of these technical variables on sampling efficacy, independent of the influence of uterine position and placental site. In that analysis, suboptimal location and/or orientation of the sampling device remained characteristic of multiple-pass cases. We conclude that further reduction in the frequency of multiple-pass procedures might be achieved by consistent placement of the device tip in the central placental mass. Unlike amniocentesis, where any point of amnion entry will suffice, this technical nuance should be emphasized with CVS to maximize the single-pass success rate.     

Congenital malformations subsequent to chorionic villus sampling: Outcome analysis of 1048 consecutive procedures

We wished to identify the types and frequencies of malformations among continuing pregnancies exposed to chorionic villus sampling (CVS) and to determine whether selected procedure-related variables differ between the normal and anomalous cohorts. CVS was performed in 1048 patients between May 1988 and January 1992. Prospective assessment of perinatal outcome was ascertained by (1) physician—patient phone contact within 1 week of sampling, (2) ultrasound evaluation of the fetal anatomy at mid-gestation, (3) a detailed post-partum questionnaire completed by the referring obstetrician, and (4) a telephone interview with each patient after the expected date of confinement. Twenty-seven major malformations were documented among 938 pregnancies (live born, n=934; electively terminated, n=4), and included cardiac malformations (5), hypospadias (5), craniosynostosis (2), pyloric stenosis (2), inguinal hernia (2), polydactyly (2), syndactyly, distal extremely hemimelia, anencephaly, hydrocephalus, cleft lip and palate, omphalocele, diaphragmatic hernia, thanatophoric dysplasia, and unilateral cataract. Normal and anomalous cohorts were similar with respect to sampling method (transabdominal/transcervical ratio), mean gestational age at CVS, single-pass success rate, and mean total sample weight. No relationship between any procedure-related variable and the risk of malformation was observed.     

冰碛物电子自旋共振信号测量的基本流程

电子自旋共振（ESR）法是一种用于直接测量和研究含有未成对电子的顺磁性物质的分析方法。ESR测年是应用这种分析方法对沉积物最后一次埋藏以来的年代进行测定。相比于其他方法,它具有测年范围广,测试的样品种类多,样品可以重复测量,测量周期短等优势。20世纪80年代以来我国开始进行沉积物ESR测年与研究,但是在冰碛物ESR测年的制样和测量过程中存在一些问题。本文介绍冰碛物ESR测年的过程：样品野外采集时剖面的选取及其注意事项;详细描述提纯冰碛物中石英颗粒的前处理过程;石英颗粒经过人工辐照后在顺磁波谱仪上测试ESR信号并拟合古剂量过程中的具体方法和需要注意的问题。从实验中得到,用0.063 —0.125 mm粒径的组分提纯石英砂比较困难,前处理过程中试剂和时间消耗量大,因此建议ESR测年时：在样品充足的情况下选用细颗粒组分（0.063—0.125 mm）,样品不充足的情况下选用中颗粒部分（0.125—0.25 mm）。待测样品中存在其他矿物会对石英的ESR信号有影响,因此在提纯石英过程中用重液分选提高石英纯度并可以增强测量的ESR信号的稳定性。经过氢氟酸刻蚀后的样品,石英的纯度要达到95%—99%或以上。对于冰碛物ESR测年过程中ESR信号的选择需要参照样品自身的特点,综合考虑多次尝试才能确定用常温Ge心信号还是低温的Al心、Ti心作为样品中石英的ESR测年信号。通过规范的采样、制样和ESR信号测量流程,使样品的定年能够被不同的人重复,并能够进行不同区域之间的对比。