Arsenic and fluoride removal from groundwater by reverse osmosis

The reverse osmosis process was evaluated for removal of naturally occurring arsenic and fluoride from groundwater. Arsenic removal was affected by the prevalent arsenic species present in the water. Arsenic concentrations were reduced by approximately 60%–90% from nearly 80 μg/L. Fluoride concentrations were reduced by approximately 60% from nearly 1.7 mg/L.     

The design of child restraint system (CRS) labels and warnings affects overall CRS usability

A study was conducted that assessed the effectiveness of different child restraint system (CRS) label/warning designs on users' installation performance. Forty-eight paid participants installed a convertible CRS in a vehicle, and two child test dummies in a CRS, using one of four label conditions. The label conditions were: (1) no labels, (2) the manufacturer's labels that were already affixed to the CRS ("Current"), (3) labels that were designed according to a combination of the current U.S. regulations concerning CRS labels and recently proposed changes to these regulations ("Proposed"), and (4) labels that were designed according to human factors principles and guidelines, and that were based on a hierarchical behavioral task analysis ("Optimal"). Results demonstrated that, overall, the Optimal labels resulted in higher usability ratings and better task performance. This indicates that labels designed using human factors and task analyses that identify critical task information requirements for label features will result in increased user compliance with instructions, higher usability, and improved task performance. Surprisingly, having no labels on the CRS resulted in better installation performance than when either the Current or the Proposed label conditions were used. This indicates that label design can decrease task performance; the actual physical design of a CRS may be just as critical as label content in the installation choices provided to the user. Collectively, results suggest that implementation of the proposed changes to the U.S. regulations concerning CRS labeling would likely not result in increased performance or usability compared to existing manufacturer labels that follow the current guidelines. In order to achieve significantly better ease-of-use and task performance, it would be necessary to implement features of the Optimal label condition.     

Risk communication in emergency response to a simulated extreme flood

Risk communication in flood incident management can be improved through developing hydrometeorological and engineering models used as tools for communicating risk between scientists and emergency management professionals. A range of such models and tools was evaluated by participating flood emergency managers during a 4-day, real-time simulation of an extreme event in the Thamesmead area in the Thames estuary close to London, England. Emergency managers have different communication needs and value new tools differently, but the indications are that a range of new tools could be beneficial in flood incident management. Provided they are communicated large model uncertainties are not necessarily unwelcome among flood emergency managers. Even so they are cautious about sharing the ownership of weather and flood modelling uncertainties.     

Transforming the Integrated Conservation and Development Project (ICDP) Approach: Observations from the Ranomafana National Park Project, Madagascar

Preservation of the biological diversity and ecosystems in protected areas can be achieved through projects linking conservation of the protected areas with improved standards of living for resident peoples within surrounding buffer zones. This is the hypothetical claim of the integrated conservation and development project (ICDP) approach to protected area management. This paper, based on several years of experience with the Ranomafana National Park Project in Madagascar, questions the major assumptions of this approach from ethical and practical perspectives. The four basic strategies available to ICDPs – protected areas, buffer zones, compensation, and economic development – are analyzed and shown to be deficient or untested in the case of Ranomafana. Recommendations are made to explore conservation models other than the western conception of the national park, to modify the notion of a buffer zone outside the protected area, to redistribute money or other resources directly to the poor people living in and around the protected areas, and to eliminate the middle men in the development business. An appeal is made to focus on local education, organization and discipline in order to promote self-determination and self-reliance among resident peoples of protected areas. The paper argues that a public works program, similar to the Roosevelt administration's Civilian Conservation Corps of the 1930s, funded through a hard-currency endowment or other innovative financing mechanism, should be tried as a replacement for the currently questionable ICDP approach at Ranomafana.     

Transvaginal chorionic villus sampling using transabdominal ultrasound guidance

Transvaginal chorionic villus sampling (CVS) using concurrent transabdominal ultrasound guidance was performed in six women who desired CVS but could not be offered transcervical or transabdominal approaches because of uterine position and placental location. Satisfactory amounts of chorionic villi were obtained in all six cases with no maternal discomfort, an occurrence that contrasts with our experience in transvaginal CVS using endovaginal ultrasound guidance. We believe that transvaginal CVS using concurrent transabdominal ultrasound guidance warrants consideration as an alternative technique for first-trimester CVS in selected patients.     

Isolating fetal nucleated red blood cells from maternal blood: The baylor experience—1995

In our previous work we have isolated fetal cells from maternal blood and used fluorescent in situ hybridization (FISH) for chromosome-specific probes to detect aneuploidy. Current efforts in the Baylor College of Medicine programme are focusing on obtaining consistency in flow-sorting methodology and on determining sensitivity and specificity. To this end, systematic evaluation of five glycophorin A (gly A) antibodies all produced agglutination, leading us to abandon the use of gly A antibodies for positive selection of fetal cells. Conversely, we have found LDS-751 to be useful for nuclear selection. CD45 negative selection can best be accomplished by the use of flasks coated with goat antibodies against mouse antibodies. Positive selection by flow sorting for either CD71⁺ cells or gamma-globin-positive cells seems to be successful. Using these two approaches, we have recently detected male (fetal) cells in pregnancies in which the fetus was 46, XY in 10 of 18 and in 12 of 14 cases, respectively.     

Significance of septations in isolated fetal cystic hygroma detected in the first trimester

Recent reports have indicated an increased risk for fetal chromosome abnormalities, especially autosomal trisomy, in fetuses with isolated cystic hygroma, or prominent nuchal membranes, detected by ultrasonography during the first trimester. However, these reports present contradictory information regarding the prognostic significance of septations within the cystic hygroma. We evaluated, in blind fashion, 55 consecutive cases of isolatd fetal cystic hygroma detected at or before 13·9 weeks' gestation to determine the association between septations and fetal chromosome complement. Septations were associated (P<0·05) with an increased risk for fetal chromosome abnormalities. However, the incidence of chromosome abnormalities was also increased (12·5 per cent) among cases not characterized by septations. Thus, we believe it prudent to offer invasive prenatal testing to all women found to be carrying fetuses with cystic hygroma, irrespective of the presence or absence of septations.     

Resorbed co-twin as an explanation for discrepant chorionic villus results: Non-mosaic 47,XX, +16 in villi (direct and culture) with normal (46,XX) amniotic fluid and neonatal blood

Non-mosaic trisomy 16 was observed in chorionic villus cytotrophoblasts (direct) as well as cultured mesenchymal core cells derived from the pregnancy of a 38-year-old woman. Chromosome preparations from amniotic fluid and neonatal cultures (cord blood) were 46,XX. Normal fetal growth as determined by serial ultrasound examinations occurred throughout the pregnancy, which resulted in a healthy 2724 g female. Multiple biopsies taken from the umbilical cord, placental cotyledons, and fetal membranes were 46,XX. However, a placental nodule and three of six cultures initiated from membranes (amnion and chorion) showed 46,XX/47,XX, + 16 mosaicism. We propose that the trisomy 16 cells arose from residual villi derived from a trisomic cotwin that never developed. This case further demonstrates that normal fetal growth may presage normal outcome irrespective of cytogenetic findings in cytotrophoblasts (direct) and cultured mesenchymal core cells.     

Isolating fetal cells in maternal circulation for prenatal diagnosis

Fetal cells unequivocally exist in and can be isolated from maternal blood. Erythroblasts, trophoblasts, granulocytes and lymphocytes have all been isolated by various density gradient and flow sorting techniques. Chromosomal abnormalities detected on isolated fetal cells include trisomy 21, trisomy 18, Klinefelter syndrome (47,XXY) and 47,XYY. Polymerase chain reaction (PCR) technology has enabled the detection of fetal sex, Mendelian disorders (e.g. β-globin mutations), HLA polymorphisms, and fetal Rhesus (D) blood type. The fetal cell type that has generated the most success is the nucleated erythrocyte; however, trophoblasts, lymphocytes and granulocytes are also considered to be present in maternal blood. Fetal cells circulate in maternal blood during the first and second trimesters, and their detection is probably not affected by Rh or ABO maternal-fetal incompatibilities. Emphasis is now directed toward determining the most practical and efficacious manner for this technique to be applied to prenatal genetic diagnosis. Only upon completion of clinical evaluations could it be considered appropriate to offer this technology as an alternative to conventional invasive and non-invasive methods of prenatal cytogenetic diagnosis.