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E Bahar

Publications and source records attributed to E Bahar.

5 recordsLinked to original sources

Double-scatter cross sections for two-dimensional random rough surfaces that exhibit backscatter enhancement.

Full-wave solutions are given for the single- and double-scatter radar cross sections for two-dimensional random rough surfaces. High-frequency approximations are used for the double-scatter cross sections in order to express them as numerically tractable four-dimensional integrals. The major contributions to the double-scatter cross sections are associated with the quasi-parallel and quasi-antiparallel double-scatter paths. They come from the neighborhoods of specular points. The enhancement of the backscatter cross sections, which is associated with the quasi-antiparallel double-scatter paths, is observed for both the like- and cross-polarized cross sections.

Journal Article↗

Reagents for the chemical development of latent fingerprints: scope and limitations of benzo[f]ninhydrin in comparison to ninhydrin.

Benzo[f]ninhydrin was compared to ninhydrin for fingerprint development on paper. Overall, the performance of ninhydrin on exhibits was slightly better than that of benzo[f]ninhydrin. The significant advantages of the benzo[f]ninhydrin over ninhydrin were the much stronger fluorescence it gave after treatment with zinc salts and a slightly quicker reaction under ambient conditions. This fluorescence is, however, similar to that obtained with other reagents, such as DFO or ninhydrin analogs. These advantages apparently are not sufficient to justify regular usage of benzo[f]ninhydrin, especially when one considers its low solubility and high cost.

Benzene↗

Structural plasticity of optic synapses in the rat suprachiasmatic nucleus: adaptation to long-term influence of light and darkness.

Synapses of optic afferents (optic synapses) in the suprachiasmatic nucleus of hooded rats were morphometrically evaluated after exposing the animals to 12 h, 14 days, 2 months, and 8 months of constant light (light rats) and darkness (dark rats). Compared with dark rats, optic synapses from light rats have larger boutons with larger mitochondria, more clear vesicles, fewer dense-core vesicles and front-line vesicles, smaller presynaptic dense projections, a smaller amount of postsynaptic density material, a smaller relative number of Gray-type I (asymmetric) junctions, a greater relative number of Gray-type II (symmetric) junctions, as well as more and larger mitochondria in the postsynaptic dendrites. Junctions of optic synapses are mostly straight, but the small number of positively curved contacts are more flattened in light rats than in dark rats. An age-related increase in the size of presynaptic dense projections was also observed. There are no changes in the sizes of clear and dense-core vesicles, in the size of synaptic junctions and their numerical density in area, and in the unspecific contact area between pre- and postsynaptic elements. The changes in optic boutons are characteristic for activated and relatively disused synapses with a slow, tonic firing rate. It appears that (1) the amount of postsynaptic density material is proportional to the strength of Gray-type I synapses, and that (2) some excitatory optic synapses become inhibitory after long-term activity, whereas some inhibitory synapses turn into excitatory contacts after long-term disuse.

Adaptation, Physiological↗

Personal and domestic hygiene and its relationship to the incidence of diarrhoea in south Sumatera.

The association of risk factors and diarrhoeal disease incidence among children less than 3 years of age in District Rambutan, South Sumatera, was investigated by a 20-week case-control study of 48 households with a high incidence of diarrhoeal diseases and 111 households with low incidence. Among sociodemographic characteristics, television ownership had a significant negative association with diarrhoeal disease incidence (odds ratio [OR] 3.22). The hygiene behaviour significantly associated with diarrhoeal diseases were: disposing of children's faeces in open places rather than in a latrine (OR > 10.47); bathing children in rivers rather than at wells (OR 2.88); children eating with their hands rather than with spoons (OR 5.6); household members defecating in open places rather than a latrine (OR 2.56); house without sewage system (OR 6.98). To control diarrhoeal disease in the study area, we suggest targeting three groups of behaviour for modification: those related to a) faeces disposal, b) sanitary drainage, and c) handwashing with soap and using spoons for eating.

Child Care↗

An epidemiological study of mental health and socioeconomic conditions in Sumatera, Indonesia.

A mental health survey was conducted in Palembang, Indonesia, to test the hypothesis that rapid socioeconomic and cultural change is detrimental to mental health. The 30-item General Health Questionnaire, translated into Bahasa Indonesia, was administered to a probability sample of 1670 adults (94.9% of the target sample). The Present State Examination was conducted on a weighted subsample of 100, using a 2-phase design. Overall morbidity rates were surprisingly similar to those in industrialized countries. A strong association was found between psychological symptoms and poverty. Persons belonging to communities that had progressed substantially in standards of living had fewer symptoms. The evidence points to a possibly beneficial effect of economic progress on mental health. Longitudinal data are needed to confirm this.

Adolescent↗