Continuous flow membrane-less air cathode microbial fuel cell with spunbonded olefin diffusion layer

The power production performance of a membrane-less air-cathode microbial fuel cell was evaluated for 53 days. Anode and cathode electrodes and the micro-fiber cloth separator were configured by sandwiching the separator between two electrodes. In addition, the air-facing side of the cathode was covered with a spunbonded olefin sheet instead of polytetrafluoroethylene (PTFE) coating to control oxygen diffusion and water loss. The configuration resulted in a low resistance of about 4Ω and a maximum power density of 750 mW/m2. However, as a result of a gradual decrease in the cathode potential, maximum power density decreased to 280 mW/m2. The declining power output was attributed to loss of platinum catalyst (8.26%) and biomass growth (38.44%) on the cathode. Coulombic efficiencies over 55% and no water leakage showed that the spunbonded olefin sheet covering the air-facing side of the cathode can be a cost-effective alternative to PTFE coating.     

Pollen counts and their relationship to meteorological factors in Ankara,Turkey during 2005–2008

Pollen plays an important role in the development and exacerbation of allergic diseases. We aimed to investigate the days with highest counts of the most allergenic pollens and to identify the meteorological factors affecting pollen counts in the atmosphere of Ankara, Turkey. Airborne pollen measurements were carried out from 2005 to 2008 with a Burkard volumetric 7-day spore trap. Microscope counts were converted into atmospheric concentrations and expressed as pollen grains/m³. Meteorological parameters were obtained from the State Meteorological Service. All statistical analyses were done with pollen counts obtained from March to October for each year. The percentages of tree, grass and weed pollens were 72.1% (n = 24,923), 12.8% (n = 4,433) and 15.1% (n = 5,219), respectively. The Pinaceae family from tree taxa (39% to 57%) and the Chenopodiaceae/Amaranthaceae family from weed taxa, contributed the highest percentage of pollen (25% to 43%), while from the grass taxa, only the Poaceae family was detected from 2005 to 2008. Poaceae and Chenopodiaceae/Amaranthaceae families, which are the most allergenic pollens, were found in high numbers from May to August in Ankara. In multiple logistic regression analysis, wind speed (OR = 1.18, CI95% = 1.02–1.36, P = 0.023) for tree pollen, daily mean temperature (OR = 1.10, CI95% = 1.04–1.17, P = 0.001) and sunshine hours (OR = 1.15, CI95% = 1.01–1.30, P = 0.033) for grass pollen, and sunshine hours (OR = 3.79, CI95% = 1.03–13.92, P = 0.044) for weed pollen were found as significant risk factors for high pollen count. The pollen calendar and its association with meteorological factors depend mainly on daily temperature, sunshine hours and wind speed, which may help draw the attention of physicians and allergic patients to days with high pollen counts.     

Improved nitrogen nutrition enhances root uptake, root-to-shoot translocation and remobilization of zinc ((65) Zn) in wheat

This study focussed on the effect of increasing nitrogen (N) supply on root uptake and root-to-shoot translocation of zinc (Zn) as well as retranslocation of foliar-applied Zn in durum wheat (Triticum durum). Nutrient solution experiments were conducted to examine the root uptake and root-to-shoot translocation of (65) Zn in seedlings precultured with different N supplies. In additional experiments, the effect of varied N nutrition on retranslocation of foliar-applied (65) Zn was tested at both the vegetative and generative stages. When N supply was increased, the (65) Zn uptake by roots was enhanced by up to threefold and the (65) Zn translocation from roots to shoots increased by up to eightfold, while plant growth was affected to a much smaller degree. Retranslocation of (65) Zn from old into young leaves and from flag leaves to grains also showed marked positive responses to increasing N supply. The results demonstrate that the N-nutritional status of wheat affects major steps in the route of Zn from the growth medium to the grain, including its uptake, xylem transport and remobilization via phloem. Thus, N is a critical player in the uptake and accumulation of Zn in plants, which deserves special attention in biofortification of food crops with Zn.     

Biomechanical pressures and upper extremity asymmetry: a study on young laborers

The purpose of this study is to reveal the impacts of biomechanical pressures of heavy working conditions on the upper extremities of young laborers. The study covers the examination of the upper extremities of 104 young laborers in the industrial workshops of Ankara, Turkey regarding bilateral asymmetry. The average age of the laborers was 18.48 +/- 0.61 years. The control group consisted of 102 non-laborers with an average age of 18.39 +/- 0.58 years. The laborers were measured with regard to width of elbows, wrists, and hands, and the length of hands. No significant difference between the groups was observed with the exception of average wrist width. However, while the labor group showed directional asymmetry in all measurements, the non-laborers exhibited directional asymmetry only in hand width and length. Consequently, the study revealed that biomechanical pressures tend to increase directional asymmetry in the upper extremities.     

Predation of entomopathogenic nematodes by <Emphasis Type="Italic">Sancassania</Emphasis> sp. (Acari: Acaridae)

Predation of the entomopathogenic nematode, Steinernema feltiae (Rhabditida: Steinernematidae), by Sancassania sp. (Acari: Acaridae) isolated from field-collected scarab larvae was examined under laboratory conditions. Adult female mites consumed more than 80% of the infective juvenile (IJ) stage of S. feltiae within 24 h. When S. feltiae IJs were exposed to the mites for 24 h and then exposed to Galleria mellonella (Lepidoptera: Pyralidae) larvae, the number of nematodes penetrating into the larvae was significantly lower compared to S. feltiae IJs that were not exposed to mites (control). Soil type significantly affected the predation rate of IJs by the mites. Mites preyed more on nematodes in sandy soil than in loamy soil. We also observed that the mites consumed more S. feltiae IJs than Heterorhabditis bacteriophora (Rhabditida: Heterorhabditidae). No phoretic relationship was observed between mites and nematodes and the nematodes did not infect the mites.     

Methylenetetrahydrofolate reductase C677T polymorphism in patients with gastric and colorectal cancer

This study was designed to investigate, in the Turkish population, an association of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and the risk of gastric and colorectal cancer. Our study was carried out in 35 patients with gastric cancer (20 men, 15 women) and 144 controls (75 men, 69 women) and 52 colorectal cancer (31 men, 21 women). MTHFR C677T genotypes were determined by polymerase chain reaction, restriction fragment length polymorphism techniques. No differences were observed in the distribution of MTHFR genotypes or allele frequencies in cases versus controls. The homozygous mutation (T/T) in the MTHFR gene was identified in 14.3% of gastric cancer versus 10.4% of controls. MTHFR C677T frequencies of the CC, CT and TT genotypes among colorectal cancer patients were 34.6%, 51.9% and 13.5%, respectively. MTHFR C677T polymorphism may not be important in an individual's susceptibility to gastric and colorectal cancer in Turkey and may not be a useful marker for identifying patients at high risk of developing gastric and colorectal cancer.     

Consequences of epididymal ligation on prepubertal rats

OBJECTIVE: To study prospectively experimental effects of unilateral epididymal obstruction on testis and epididymis histopathologically in prepubertal rats. STUDY DESIGN: Organ weights, mean seminiferous tubule diameter (MSTD), mean ductus epididymis diameter (MDED), mean tubular biopsy scores (MTBS) and histopathology of 21 male albino Wistar rats were compared with the immunostaining affinity of anti-desmin, anti-vimentin, anti-laminin and anti-collagen antibodies. RESULTS: Statistical analysis of mean weight of testes, MTBS, mean epididymal weight, MDED and MSTD was significant. Evaluation of testis and epididymis revealed cellular damage, basal membrane impairment and granulomatous infiltration. CONCLUSION: Histopathologic alterations with MSTD are early indicators for ipsilateral and contralateral injury. Even the presence of criteria such as intactness and cellular integrity does not guarantee there is no sperm leakage or immunologic damage. Therefore the impairment of basal integrity is a switch code in determining spermatogenic failure.     

Mitochondrial iron transporter (MIT) gene in potato (Solanum tuberosum): comparative bioinformatics,physiological and expression analyses in response to drought and salinity

BioMetals - Mitochondrial iron transporter (MIT) genes are essential for mitochondrial acquisition/import of iron and vital to proper functioning of mitochondria. Unlike other organisms, research...