Detection of fetal cells in transcervical samples and prenatal diagnosis of chromosomal abnormalities

Transcervical samples collected by lavage, aspiration, and cytobrush from women between 6 and 13 weeks of gestation were tested for the presence of fetal cells using fluorescence in situ hybridization (FISH) with probes for chromosomes X, Y, 1, and 21, and by polymerase chain reaction (PCR) amplification of DNA sequences derived from chromosomes X, Y, and 21. With a few exceptions, a good correlation was observed between the results of sexing the fetuses using FISH or PCR on transcervical cell (TCC) samples retrieved by lavage and those obtained by testing fetal (placental) tissue. In a comparative study between TCC samples collected by lavage or cytobrush, the sex of the fetus was correctly diagnosed by PCR amplification of a Y-derived DNA sequence. Variable results were observed with samples obtained by aspiration, mainly because this procedure was found to be more prone to failure to remove thick mucus without previous injection of physiological saline. Chromosome 21-derived small tandem repeats (STRs) of fetal origin were successfully detected in about 40 per cent of TCC samples recovered by lavage. Two cases of chromosomal abnormalities, one of trisomy 21 and one of triploidy, were detected in TCC samples in the course of our investigations.     

Spatial variation of phosphorus fractionation in the coral reef sediments of Lakshadweep Archipelago,Indian Ocean

Surface sediments were collected from the shore and lagoons of Kavaratti, Kadamat and Agatti islands of Lakshadweep Archipelago during May 2015 and analysed for the spatial distribution of the micronutrient element, phosphorus. Phosphorus was separated by sequential extraction procedure into five fractions – exchangeable (Ex-P), iron bound, (Fe-P), calcium bound (Ca-P), organic and residual fractions (OP) and total phosphorus (TP). The average relative contribution of each P species to TP was: OP?>?Ca –P?>?Ex – P?>?Fe – P. The high concentration of organic and residual phosphorus (87–96%) compared to inorganic phosphorus is particularly evident at stations characterised by higher total phosphorus concentrations. Among the three forms of IP in the sediments, Ca-P was dominant at all stations. The OC/OP ratio ranged from 3 to 163 in the sediments, suggesting that the organic matter in sediments had been subjected to degradation. Hence, the major contribution towards organic and residual phosphorus form is from the residual fraction comprising biologically resistant or non-available phosphorus form composed of refractory materials. The concentration of phosphorus reported in the present study is higher than that of the earlier studies in Lakshadweep, indicating a terrestrial and anthropogenic in?uence on the sediment.     

Safety evaluation of cable barriers installation on rural highways in British Columbia

Objective: The objective of this study was to evaluate the safety effectiveness of cable barrier systems installation on rural highway sections in British Columbia, Canada.

Methods: Data on police-attended serious collisions (injury?+?fatality) on a number of rural highway sections in British Columbia, Canada, were used in the analysis. An empirical Bayes (EB) approach was employed to ensure that the evaluation results were reliable and to account for the regression to the mean artifact. Safety performance functions (SPFs) were developed using data collected at similar sites. For both median cable barrier (MCB) and roadside cable barrier (RCB) sections, the evaluation was undertaken using all serious collisions, truck serious collisions, and off-road serious collisions.

Results: For MCB sections, the evaluation results showed statistically significant reductions of 21.7, 53.8, and 34.8% in all serious collisions, truck serious collisions, and off-road left (ORL) combined with head-on (HO) serious collisions. For RCB sections, statistically significant reductions of 74.7, 100, and 100% were found in all serious collisions, truck serious collisions, and off-road right (ORR) serious collisions, respectively. The impact of the after period on the evaluation results was explored. It was found that the changes in safety become more stable using an after period of 2–5 years.

Conclusions: Cable barriers were successful in reducing the frequency of serious collisions on provincial highways in British Columbia.     

Re-politicising water governance: exploring water re-allocations in terms of justice

Contemporary socio-economic transformations in South Asia are creating increasingly serious water problems (scarcity, flooding, pollution) and conflicts. Conflicts over water distribution, water-derived benefits, and risks often play out along axes of social differentiation like caste, wealth, and gender. Those with least power, rights, and voice suffer lack of access, exclusion, dispossession, and further marginalisation, resulting in livelihood insecurity or increased vulnerability to risks. In this paper we propose analysing these problems as problems of justice – problems of distribution, recognition, and political participation. Drawing on wider environmental justice approaches, a specific water justice focus needs to include both the specific characteristics of water as a resource and the access, rights, and equity dimensions of its control. We argue that recognising water problems as problems of justice requires a re-politicisation of water, as mainstream approaches to water resources, water governance, and legislation tend to normalise or naturalise their – basically political – distributional assumptions and implications. An interdisciplinary approach that sees water as simultaneously natural (material) and social is important here. We illustrate these conceptual and theoretical suggestions with evidence from India.     

The Definition of Brownfield

This paper discusses the need for a more robust definition of the term 'brownfield' from a multidisciplinary perspective. It examines the issues involved in constructing an agreed and accepted definition and its importance with regard to UK government policy. Current usage of the term 'brownfield' and related terminology is reviewed. The paper proposes that: a brownfield site is any land or premises which has previously been used or developed and is not currently fully in use, although it may be partially occupied or utilized. It may also be vacant, derelict or contaminated. Therefore a brownfield site is not necessarily available for immediate use without intervention. Interpretation of the terminology incorporated with the definition is presented herein. The definition is subsequently evaluated with respect to the views of different stakeholder groups involved in the redevelopment of brownfield sites.     

Evaluation of various global solar radiation models for Nigeria

This study assessed the performance of six solar radiation models. The objective was to determine the most accurate model for estimating global solar radiation on a horizontal surface in Nigeria. Twenty-two years meteorological data sets collected from the Nigerian Meteorological agency and the National Aeronautics and Space Administration for the three regions, covering the entire climatic zones in Nigeria were utilized for calibrating and validating the selected models for Nigeria. The accuracy and applicability of various models were determined for three locations (Abuja, Benin City, and Sokoto), which spread across Nigeria using seven viable statistical indices. This study found that the estimation results of considered models are statistically significant at the 95% confidence level, but their accuracy varies from one location to another. However, the multivariable regression relationship deduced in terms of sunshine ratio, air temperature ratio, maximum air temperature, and cloudiness performs better than other relationships. The multivariable relationship has the least root mean square error and mean absolute bias error, not exceeding 1.0854 and 0.8160 MJ m^?2 day^?1, respectively, and monthly relative percentage error in the range of ± 12% for the study areas.     

Preimplantation genetic diagnosis for single gene disorders: experience with five single gene disorders

We report our experience of 14 preimplantation genetic diagnosis (PGD) cycles in eight couples carrying five different single gene disorders, during the last 18 months. Diagnoses were performed for myotonic dystrophy (DM), cystic fibrosis (CF) [ΔF508 and exon 4 (621+1 G>T)], fragile X and CF simultaneously, and two disorders for which PGD had not been previously attempted, namely neurofibromatosis type 2 (NF2) and Crouzon syndrome. Diagnoses for single gene disorders were carried out on ideally two blastomeres biopsied from Day 3 embryos. A highly polymorphic marker was included in each diagnosis to control against contamination. For the dominant disorders, where possible, linked polymorphisms provided an additional means of determining the genotype of the embryo hence reducing the risk of misdiagnosis due to allele dropout (ADO). Multiplex fluorescent polymerase chain reaction (F-PCR) was used in all cases, followed by fragment analysis and/or single-stranded conformation polymorphism (SSCP) for genotyping. Embryo transfer was performed in 13 cycles resulting in one biochemical pregnancy for CF, three normal deliveries (a twin and a singleton) and one early miscarriage for DM and a singleton for Crouzon syndrome. In each case the untransferred embryos were used to confirm the diagnoses performed on the biopsied cells. The results were concordant in all cases. The inclusion of a polymorphic marker allowed the detection of extraneous DNA contamination in two cells from one case. Knowing the genotype of the contaminating DNA allowed its origin to be traced. All five pregnancies were obtained from embryos in which two blastomeres were biopsied for the diagnosis. Our data demonstrate the successful strategy of using multiplex PCR to simultaneously amplify the mutation site and a polymorphic locus, fluorescent PCR technology to achieve greater sensitivity, and two-cell biopsy to increase the efficiency and success of diagnoses. Copyright © 2002 John Wiley & Sons, Ltd.     

Conversion of chicken feather waste via hydrothermal carbonization: process optimization and the effect of hydrochar on seed germination of Acacia auriculiformis

Journal of Material Cycles and Waste Management - Using statistical response surface methodology this paper primarily investigates the role of process parameters at different levels (temperature,...     

Development and applications of functional gene microarrays in the analysis of the functional diversity, composition, and structure of microbial communities

Functional gene arrays (FGAs) are a special type of microarrays containing probes for key genes involved in microbial functional processes, such as biogeochemical cycling of carbon, nitrogen, sulfur, phosphorus, and metals, biodegradation of environmental contaminants, energy processing, and stress responses. GeoChips are considered as the most comprehensive FGAs. Experimentally established probe design criteria and a computational pipeline integrating sequence retrieval, probe design and verification, array construction, data analysis, and automatic update are used to develop the GeoChip technology. GeoChip has been systematically evaluated and demonstrated to be a powerful tool for rapid, specific, sensitive, and quantitative analysis of microbial communities in a high-throughput manner. Several generations of GeoChip have been developed and applied to investigate the functional diversity, composition, structure, function, and dynamics of a variety of microbial communities from different habitats, such as water, soil, marine, bioreactor, human microbiome, and extreme ecosystems. GeoChip is able to address fundamental questions related to global change, bioenergy, bioremediation, agricultural operation, land use, human health, environmental restoration, and ecological theories and to link the microbial community structure to environmental factors and ecosystem functioning.