Yearly, huge amounts of sock refuse are discarded into the environment. Socks contain many molecules, and worn ones, which are rich in smell-causing bacteria, have a strong influence on animals’ behaviors. But the impacts of sock odor on the oviposition behavior of dengue vectors are unknown. We assessed whether Aedes albopictus changes its oviposition activity in response to the presence of used socks extract (USEx) in potential breeding grounds, using choice and no-choice bioassays (NCB). When furnished even chances to oviposit in two sites holding USEx and two others containing water (control), Ae. albopictus deposited significantly less eggs in USEx than in water sites. A similar pattern of oviposition preference was also observed when there were more oviposition options in water. When there were greater oviposition opportunities in USEx sites, Ae. albopictus oviposited preferentially in water. Females laid significantly more eggs during the NCB involving water than USEx. Also, significantly more mature eggs were retained by females in the NCB with USEx than in that with water. These observations strongly suggest the presence of molecules with either repellent or deterrent activities against Ae. albopictus females and provide an impetus to advocate the integration of used socks in dengue control programs. Such applications could be a realistic end-of-life recourse to reroute this waste from landfills.
The variation of mechanical properties such as tensile and flexural properties of randomly oriented unsaturated polyester
based sisal/carbon fibre reinforced hybrid composites with different fibre weight ratios have been studied. The chemical resistance
test of these hybrid composites to various solvents, acids and alkalies were studied. The effect of NaOH treatment of sisal
fibres on the tensile, flexural and chemical resistance properties of these sisal/carbon hybrid composites has also been studied.
The hybrid composites showed an increase in tensile and flexural properties with increase in the carbon fibre loading. The
tensile properties and flexural properties of these hybrid composites have been found to be higher than that of the matrix.
Significant improvement in tensile properties and flexural properties of the sisal/carbon hybrid composites has been observed
by alkali treatment. The chemical resistance test results showed that these untreated and alkali treated hybrid composites
are résistance to all chemicals except carbon tetra chloride. Hand lay-up technique was used for making the composites and
tests are carried out by using ASTM methods. 相似文献
Catla gill cell line (ICG) was established from gill tissue of Indian major carp (Catla catla), a freshwater fish cultivated in India. The cell line was maintained in Leibovitz’s L-15 supplemented with 10% fetal bovine serum. These cells have been sub-cultured more than 55 passages over a period of 2 years. The ICG cell line consists predominantly of epithelial-like cells. The cells were able to grow at a wide range of temperatures from 24 °C to 32 °C with an optimum temperature of 28 °C. The growth rate of gill cells increased as the fetal bovine serum (FBS) proportion increased from 2% to 20% at 28 °C with optimum growth at the concentrations of 10% or 15% FBS. Amplification of mitochondrial gene 12s rRNA using primers specific to C. catla confirmed the origin of this cell line from C. catla. The cells were successfully cryopreserved and revived at passage numbers 25, 35, 45 and 55. The cytotoxicity of three metal salts (ZnCl2, CuSO4 and CdCl2) was assessed in ICG cell line using multiple endpoints such as MTT, Neutral Red assay, Alamar Blue assay and Coomassie Blue protein assay. Acute toxicity assay on fish were conducted by exposing C. catla for 96 h to three metal salts under static conditions. Statistical analysis revealed good correlation with r2 = 0.908–0.985 for all combinations between endpoints employed. Linear correlations between each in vitro EC50 and the in vivo LC50 data were highly significant. 相似文献
A total of 35 bacteria from contaminated soil (cultivated fields) near pesticide industry from Chinhat, Lucknow, (India) were isolated and tested for their tolerance/resistance to pesticides, heavy metals and antibiotics. Bacterial isolates were identified by 16S rDNA sequencing. Gas Chromatography analysis of the soil samples revealed the presence of lindane at a concentration of 547 ng g−1 and α-endosulfan and β-endosulfan of 422 ng g−1 and 421 ng g−1 respectively. Atomic Absorption Spectrophotometry analysis of the test sample was done and Cr, Zn, Ni, Fe, Cu and Cd were detected at concentrations of 36.2, 42.5, 43.2, 241, 13.3 and 11.20 mg kg−1 respectively. Minimum inhibitory concentrations of all the isolates were determined for pesticides and heavy metals. All the multi-resistant/tolerant bacterial isolates were also tested for the presence of incompatibility (Inc) group IncP, IncN, IncW, IncQ plasmids and for rolling circle plasmids of the pMV158-family by PCR. Total community DNA was extracted from pesticide contaminated soil. PCR amplification of the bacterial isolates and soil DNA revealed the presence of IncP-specific sequences (trfA2 and oriT) which was confirmed by dot blot hybridization with RP4-derived DIG-labelled probes. Plasmids belonging to IncN, IncW and IncQ group were neither detected in the bacterial isolates nor in total soil DNA. The presence of conjugative or mobilizable IncP plasmids in the isolates indicate that these bacteria have gene transfer capacity with implications for dissemination of heavy metal and antibiotic resistance genes. We propose that IncP plasmids are mainly responsible for the spread of multi-resistant bacteria in the contaminated soils. 相似文献
In this research, hybrid composite materials were prepared from combination of oil palm Empty fruit bunches (EFB) fibre and
jute fibre as reinforcement, epoxy as polymer matrix. This study intended to investigate the effect of jute fiber hybridization
and different layering pattern on the physical properties of oil palm EFB-Epoxy composites. Water absorption and thickness
swelling test reveal that hybrid composite shows a moderate water absorption which is 11.20% for hybrid EFB/Jute/EFB composite
and 6.08% for hybrid Jute/EFB/Jute composite. The thickness swelling and water absorption of the hybrid composites slightly
increased as the layering pattern of hybrid composites changed. Hybrid composites are more water resistance and dimensional
stable compare to the pure EFB composites. This is attributed to the more hydrophilic nature of EFB composites. Hybridization
of oil palm EFB composites with jute fibres can improve the dimensional stability and density of pure EFB and Jute fibre reinforced
composites has higher density of 1.2 g/cm3 compared to all other composites. 相似文献
Solid waste management (SWM) is one of the most challenging issues faced by developing countries that suffer from serious pollution problems caused by the generation of large waste quantities. This paper presents the case study of SWM in the Nablus district – Palestine. Surveys for household residents' and SWM program operators, field investigations, on-site waste measurements and characterizations were conducted. Per capita waste generation rates varied between different localities although trends were similar. Overall, the majority of waste was organic (65.1% by weight), suggesting a strong resource recovery potential in terms of animal feed or compost. Recyclable waste (plastic, paper and card) made up 16.7% by weight the waste composition suggesting an incentive to introduce source separation. Household attitudes complemented the waste characterization study, revealing the main problems faced. SWM operators quoted on the current status, highlighting problems with disposing in unsanitary landfills, ineffective solid waste fees system, increasing solid waste quantities and lacking equipment and experienced personnel. To enhance sustainable SWM, public awareness, funding, expertise, equipment and facilities and other provisions currently lacking or inappropriate must be provided. 相似文献
This replicated 4×2 factorial study investigated the bioaccumulation of selected metals (Mn, Pb, Zn, Hg and Cr) in four tissues (gills, liver, muscle and skin) of common carp (Cyprinus carpio) domiciled in two sites (upstream and downstream) of Indus River in Mianwali district of Pakistan. The data were statistically compared for the main effects of the site and fish organs and their interaction on the bioaccumulation pattern of these metals in fish organs at P?0.05. It appeared that the fish sampled from downstream had higher trace metals than the fish from upstream. Significant differences between fish organs were observed for these trace metals (P?0.001). The fish showed higher bioaccumulation of vital metals like Zn and lower bioaccumulation for the toxic metals like Pb. The gills had the highest metal load followed by liver, skin and muscles. High concentrations of Mn, Hg and Cr were observed in different fish organs as compared to the WHO and Federal Environmental Protection Agency standards for food fish. However, the mean concentration of Pb and Zn were under the permissible limits of food fish. It implies that higher levels of Mn, Hg and Cr in fish muscles would have detrimental effects on the health of fish consumers such as pregnant women, children and elderly people of this study area. 相似文献
This study analyzes and compares the results of leachate composition at the semi-aerobic Pulau Burung Landfill Site (PBLS) (unaerated pond and intermittently aerated pond) and the anaerobic Kulim Sanitary Landfill in the northern region of Malaysia. The raw samples were collected and analyzed for twenty parameters. The average values of the parameters such as phenols (1.2, 6.7, and 2.6 mg/L), total nitrogen (448, 1200, and 300 mg/L N-TN), ammonia-N (542, 1568, and 538 mg/L NH3-N), nitrite (91, 49, and 52 mg/L NO2?-N), total phosphorus (21, 17, and 19 mg/L), BOD5 (83, 243, and 326 mg/L), COD (935, 2345, and 1892 mg/L), BOD5/COD (0.096,0.1124,0.205%), pH (8.20, 8.28, and 7.76), turbidity (1546, 180, and 1936 Formazin attenuation units (FAU)), and color (3334, 3347, and 4041 Pt Co) for leachate at the semi-aerobic PBLS (unaerated and intermittently aerated) and the anaerobic Kulim Sanitary Landfill were recorded, respectively. The obtained results were compared with previously published data and data from the Malaysia Environmental Quality Act 1974. The results indicated that Pulau Burung leachate was more stabilized compared with Kulim leachate. Furthermore, the aeration process in PBLS has a considerable effect on reducing the concentration of several pollutants. The studied leachate requires treatment to minimize the pollutants to an acceptable level prior to discharge into water courses. 相似文献
Environmental Science and Pollution Research - Polychlorinated biphenyls (PCBs) are toxic organic compounds and pose serious threats to environment and public health. PCBs still exist in different... 相似文献