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In this work composition, size, morphology and other physical quantities dependency of the most widespread face respirators and surgery masks are investigated using different aerosol sources in the submicron size domain. The airborne filtration efficiency of the sample materials are also demonstrated here. We have experimentally demonstrated high filtration efficiency of NaCl, soot, DEHS and distilled water as well as airborne aerosols with limited size dependency. Using different mixing of distilled water and Sodium Lauryl Sulphate (SLS) surface tension dependency of filtration efficiency have been also quantified. It is experimentally demonstrated that the filtration efficiency is increased with increasing surface tension and the highest filtration efficiency have been realised with salvia equivalent surface tension value regardless of the sampled respirators or surgery mask. Finally, we also experimentally demonstrated that respirators has higher filtration efficiency than that of surgery mask and that the exhalation direction of the flow has negligible effect on filtration efficiency in all samples.

Nitric oxide (NO) gas concentrations are higher in expired air in asthmatics. NO is synthesized by three isoforms of NO synthase (NOS) encoded by three distinct genes, NOS1, NOS2, and NOS3. Genome-wide searches have identified linkages to asthma on chromosomes 7, 12, and 17 where these three genes are localized. No association study, however, has been reported to date. To test whether variants of NOS1, NOS2, and NOS3 relate to asthma, a genetic association study was conducted in a British population (n = 300). Intragenic microsatellite variants of NOS1 were significantly associated with asthma [odds ratio (OR) = 2.08, 95% CI: 1.20–3.57 (95% CI), P = 0.008 (Pc = 0.048)], but not with IgE levels. Neither NOS2 nor NOS3 variants showed any association with asthma nor IgE levels. These findings suggest that NOS1 variants may be a significant contributor to asthma in a British population.

Nasal colonisation with Staphylococcus aureus is a risk factor for invasive infection in human immunodeficiency virus (HIV)-positive individuals. This study aimed to characterise colonising S. aureus from regions with a high HIV prevalence. Single nasal swabs were taken from a total of 374 HIV-positive and 370 healthy individuals. Overall, 202 S. aureus carriers were detected. Compared with healthy individuals, HIV-positive subjects were more likely to be S. aureus nasal carriers (33% vs. 21%; P=0.0001). Isolates from HIV-positive individuals were more often resistant to meticillin (16% vs. 8%; P=0.13), chloramphenicol (47% vs. 16%; P

It is difficult to process and analyze remote sensing owning to cloudy and strips in the image, so we propose a new method to reduce cloud in space-borne image with multi-temporal data based on wavelet transformation. The images are decomposed into low frequency information and high frequency information using Mallet algorithm. Normalized difference low frequency index between two temporal images with cloud is used to reduce the low frequency information because the clouds are low frequency information and they mainly appear in low frequency wavelet coefficients, and higher frequency information of image is also extracted from two high frequency information. The reconstructed image using reduced low frequency and extracted by high frequency wavelet transformation is a new image without cloud. Two real space-borne images with clouds are processed using the proposed method and the result demonstrates that the method is feasible. Stripes also appear in some space-borne images and they are high infrequency information, so they clearly appear in wavelet field, and we reduce high infrequency of strips in wavelet field. The striped image is decomposed into several layers using wavelet transformation, and the strips are appear clearly as lines in high frequency block in each layer. Projection histogram is used to reduce the lines in high frequency block The reduced higher frequency information ant low information are reconstructed into a new image without stripes. We use the wavelet transform method to reduce TM space-borne image with strips, and the processed result shows that wavelet transform is a better method.

We assessed the prevalence of Plasmodium falciparum and the frequency of the dhfr triple mutation that is associated with antifolate drug resistance among P. falciparumisolates obtained from pregnant women in Ilorin, Nigeria. The study included 179 women in the second and third trimester of pregnancy who have been exposed to intermittent preventive treatment in pregnancy (IPTp) with sulfadoxinepyrimethamine. Thick and thin blood films and PCR were used for malaria parasite detection. Blood group and hemoglobin concentration were also determined. Mutations in P. falciparum dhfr were analyzed by sequencing DNA obtained from blood spots on filter paper. Prevalence of P. falciparum in the population (PCR corrected) was 44.1% (79/179) with 66.7% and 33.3% in the second and third trimester, respectively. Primigravide (51.3%) were more infected than multigravide (48.7%) but the difference was not statistically significant. Women in blood group A had the highest P. falciparum malaria infection (30.8%). The mean hemoglobin concentration was lower among those infected with malaria parasite. Also, more women with the malaria parasite (38.4%) had anemia compare to those without (21.4%). The prevalence of the P. falciparum dhfr mutant alleles was 64.1%, 61.5%, 38.5%, and 12.8% for I51, R59, N108 and T108, respectively. None of the samples had the L164 mutation. The combined triple dhfr mutation (51 + 59 + 108) in the population was 17.9% (7 of 39). Also, the prevalence of the triple mutant alleles was not significantly associated to the number of doses of SP taken by the women. These findings highlight the need for a regular assessment of IPTp/SP efficacy, and evaluation of possible alternative drugs.