Prenatal diagnosis of spinal muscular atrophy in Russia

Ninety-two families with spinal muscular atrophy (SMA) applied for genetic counselling and further prenatal diagnosis. To minimize expenses, only one tightly linked informative marker was determined in the course of preliminary examination, and non-radioactive allele detection was preferably used. Four prenatal diagnoses of SMA type I, four of SMA type II, and one of SMA type III were made. This trial programme shows the considerable requirements, importance, and potential effectiveness of prenatal prediction of SMA in Russia.     

Implications of climate change on mitigation potential estimates for forest sector in India

Climate change is projected to impact forest ecosystems, including biodiversity and Net Primary Productivity (NPP). National level carbon forest sector mitigation potential estimates are available for India; however impacts of projected climate change are not included in the mitigation potential estimates. Change in NPP (in gC/m²/yr) is taken to represent the impacts of climate change. Long term impacts of climate change (2085) on the NPP of Indian forests are available; however no such regional estimates are available for short and medium terms. The present study based on GCM climatology scenarios projects the short, medium and long term impacts of climate change on forest ecosystems especially on NPP using BIOME4 vegetation model. We estimate that under A2 scenario by the year 2030 the NPP changes by (−5) to 40% across different agro-ecological zones (AEZ). By 2050 it increases by 15% to 59% and by 2070 it increases by 34 to 84%. However, under B2 scenario it increases only by 3 to 25%, 3.5 to 34% and (−2.5) to 38% respectively, in the same time periods. The cumulative mitigation potential is estimated to increase by up to 21% (by nearly 1 GtC) under A2 scenario between the years 2008 and 2108, whereas, under B2 the mitigation potential increases only by 14% (646 MtC). However, cumulative mitigation potential estimates obtained from IBIS—a dynamic global vegetation model suggest much smaller gains, where mitigation potential increases by only 6% and 5% during the period 2008 to 2108.     

Use of coatings to minimise acid emissions during ceramic tile firing

The manufacture of traditional ceramic products (ceramic tiles, roof tiles, and bricks) is often associated with the emission of F, Cl, and S compounds during the firing stage. According to the literature, fluorine emissions can be reduced by adding CaCO₃ to the raw materials mixture used in fabricating these products. However, data available to the authors indicate that this procedure, which has been successfully applied in manufacturing structural ceramics (roof tiles and bricks), is ineffective in ceramic tile manufacture and modifies tile end properties.This paper examines the possibility of reducing such emissions by applying coatings of alkaline-earth carbonates on to the ceramic tile bottom surface to retain the acid compounds emitted during tile firing. The effectiveness of MgCO₃, CaCO₃, SrCO₃, and BaCO₃ coatings for retaining these acid emissions was studied, using the evolved gas analysis (EGA) technique with a TG-DSC-FTIR-QM instrument.The SrCO₃ coating was found to provide the greatest retention, showing that SO₂ and HCl were retained more efficiently than HF. The presence of fluorides, chlorides, and sulphates of Ca, Sr, and Ba was verified in the respective fired coatings, confirming the existence of chemical reactions between the emitted acid compounds and the coating materials at high temperature.     

Numerical simulation of propane detonation in medium and large scale geometries

A modelling strategy has been developed for consequence analysis of medium and large scale gaseous detonation. The model is based on the solution of Euler equations with one-step chemistry. The Van Leer flux limited method which is a total variation diminishing scheme is used for shock capturing. Preliminary calculations were firstly conducted for small domains with fine grids which resolve the wave, relatively coarse grids which have less than 10 grids across the wave and coarse grids in which the minimum grid size is larger than the wave thickness to ensure that the reaction scheme has been properly tuned to capture the correct detonation pressure, temperature and velocity in the resolutions used in the different cases. The model was firstly tested against a medium scale detonation test in a shock tube with U-bends. Reasonably good agreement is achieved on detonation pressure and mean shock wave velocities at different measuring segments of the tube. Following the validation, the detonation of a hypothetical planar propane-air cloud is simulated. The predictions uncovered some interesting features of such large scale detonation phenomena which are of significance in the safety context, especially for accidental investigations. The findings from the present analysis are in line with the forensic evidence on damages in some historic accidents and challenges previous analysis of a major accident in which forensic evidence suggested localised detonation but was considered as the consequence of fire storms by the investigation team.     

Extraction of DNA from amniotic fluid cells for the early prenatal diagnosis of genetic disease

Ten-ml samples of amniotic fluid were taken from pregnancies being terminated at 8–14 weeks' gestation. DNA was extracted from the amniotic cells by sequential centrifugation and analysed using the polymerase chain reaction (PCR). Fifteen samples were analysed for evidence of maternal contamination using Mfd5 oligo-nucleotide primers for repeat polymorphisms. Ten amniotic fluid samples were tested for the Delta-F₅₀₈ deletion characteristic of cystic fibrosis to demonstrate a diagnostic application for the technique. In each case, DNA extracted from fetal tissue from the same pregnancy was included in the controls. In 14 of the 15 cases tested with the Mfd5 primers, both the amniotic fluid DNA and the fetal DNA showed no evidence of contaminating DNA. In one case, neither the amniotic fluid cells nor the fetal cells yielded results. In nine of the ten cases tested with the Delta-F₅₀₈ primers, the amniotic fluid cell DNA provided accurate information about the genetic status of the fetus; in the tenth, the fetal DNA failed to amplify. The results indicate that adequate DNA can be extracted from amniotic fluid from 8 weeks' gestation onward and these samples are suitable for prenatal diagnosis using PCR.     

Prenatal ultrasound diagnosis of Apert's syndrome

A mother affected with Apert's syndrome was diagnosed by ultrasound scan at 16–17 weeks to have a fetus similarly affected. The typical features of acrocephaly and symmetrical syndactyly were seen. This is probably the first time that this condition has been diagnosed at such a gestation by ultrasound scan. The patient decided to continue the pregnancy, and intrauterine death occurred at 34 weeks. The diagnosis was confirmed by pathological examination.