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11.
Salman Qureshi Syed Jamil Hasan Kazmi Jürgen H. Breuste 《Urban Forestry & Urban Greening》2010,9(3):187-198
This paper evaluates the changes to the green infrastructure of the megacity of Karachi, Pakistan, occurring during a period of rapid development, involving extensive loss of trees and green spaces since 2000, occurring as a consequence of road widening and improvements to the city's transport infrastructure, aggravated by a series of cyclones, involving further tree loss and which has led to numerous ecological problems in the city, assessing how the effect of the reduction of Karachi's green infrastructure has impacted both the reality and the perception of human health conditions. It uses medium-resolution satellite images classified for land use and land cover (LULC) data extraction and detailed field surveys to map the extent of change; structured questionnaires are used to identify the perception of selected, targeted groups regarding the state of Karachi's urban green infrastructure and perceived human health conditions. Findings indicate that the public perception of green space functionality or presence does not equate with the remote sensing and field mapping results, which show a dramatic loss. The need to develop a comprehensive urban greening strategy, which considers the needs and priorities of the population, is identified. The impact of such a strategy in terms of increased frequency of visits to green sites and associated increase in the physical activity of the people to improve overall physical health is discussed in relation to the general development of Karachi. 相似文献
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13.
Fifty canine fecal samples were evaluated by five flotation procedures to compare the sensitivity of the zinc sulfate (ZnSO4) centrifugation flotation test with ZnSO4 flotation tests using benchtop incubation during the flotation period. One or more parasite species were detected in 40 samples. Results showed that centrifugation with ZnSO4 solution was significantly more likely to detect a positive sample than benchtop procedures. The difference in procedures was due primarily to increased detection of Trichuris eggs and Giardia cysts by centrifugal flotation. No significant difference was seen in the ability of benchtop procedures to detect positive samples when tests sat either for 5 or 10 minutes before examination. 相似文献
14.
Mondal Satyen Jamil Hasan M. Ahmed Tofayel Giashuddin Miah M. C. Sta Cruz Pompe M. Ismail Abdel 《水稻科学》2020,27(6):515-528
Rice (Oryza sativa) plants acquired excess photosynthates in the form of nonstructural carbohydrates (NSCs) in their stems and grain. Despite keen interest in rice NSC, the dynamics of NSC accumulation, translocation and re-accumulation have not yet been well investigated. AG1 and AG2 QTLs associated with flooding tolerance through catalyzing starch into soluble sugar in germinating seeds. Here we conducted three experiments, greenhouse and field to lay the groundwork for large-scale diversity studies on grain NSC and some agronomic traits under direct-seeded rice (DSR) system, using elite lines incorporating AG1, AG2 and AG1-AG2 QTLs into the popular varieties PSB Rc82 and Ciherang-Sub1 along with the donors Kho Hlan On (AG1) and Ma-Zhan Red (AG2). In germinating seedlings, soluble sugars increased, while starch concentration decreased gradually especially in the tolerant checks and AG1-AG2 introgression lines under flooded soil. Soluble sugar accumulation in stem started to increase from the vegetative stage and peaked at the panicle initiation stage then gradually decreased towards the maturity stage. But Sub1-AG lines had higher sugar and starch concentrations at different growth stages than other genotypes in wet season 2016 and dry season 2017. Plant survival rate was positively correlated with the stem NSC at the early vegetative stage (21 days after sowing), and stem NSC was positively associated with plant height at different growth stages. Among the tested seeding rate, the most suitable seeding rate, 4 g/m2 with shallow burial depth (0.5 cm), resulted in better seedling establishment, relatively higher seedling vigor index and higher leaf area index under flooding in DSR system. Introgression of AG1-AG2 QTLs had no any negative impact on nonstructural carbohydrate, germination rate, and growth and biomass production. 相似文献
15.
Hyena disease was first reported in France in 1975 and since then has been recognized in many countries. It is currently regarded as a disorder of skeletal development, mainly localised in the pelvic limbs of young cattle. Some investigators consider that it is a metabolic disease but the authors believe that it may be caused by a virus. Their hypothesis, according to which bovine virus diarrhoea-mucosal disease virus is involved, is based on epidemiological, histopathological and immunological evidence. 相似文献
16.
Background
Evidence of trivalent manganese (Mn3+) in the aqueous phase of soils is unknown so far although this strong oxidant has large environmental implications.Aims
We aimed to modify a spectrophotometric protocol (porphyrin method) and to discriminate between Mn2+ and Mn3+ in the aqueous phase of forest soils based on kinetic modeling.Methods
We investigated manganese speciation in 12 forest floor solutions and 41 soil solutions from an acidic forest site by adjusting pH and correcting for absorbance.Results
The solutions showed broad ranges in pH (3.4−6.3), dissolved organic carbon (DOC, 1.78−77.1 mg C L−1), and total Mn (MnT, 23.9−908 µg L−1). For acidic solutions, a pH-buffer was added to increase the pH of the solutions to 7.5−8.0, and background absorption was corrected for colored solutions, that is, solutions high in DOC. This was done to accelerate the reaction kinetics and avoid overestimation of MnT concentrations. After the pH and color adjustments, the comparison of MnT concentrations between the porphyrin method and optical emission spectrometry showed good agreement. Trivalent Mn, which is stabilized by organic ligands, constitutes significant proportions in both forest floor solutions (10−87%) and soil solutions (0.5−74%).Conclusions
The dissolved Mn3+ is present in acidic forest soils. Thus, we revise the paradigm that this species is not stable and encourage to apply the revised method to other soils. 相似文献17.
Comparison of biuret and refractometry methods for the serum total proteins measurement in ruminants 下载免费PDF全文
18.
Mircea Constantin Sora Christoph von Horst Octavio Lpez-Albors Rafael Latorre 《Anatomia, histologia, embryologia》2019,48(6):564-571
With classical sheet plastination techniques such as E12, the level and thickness of the freeze‐cut sections decide on what is visible in the final sheet plastinated sections. However, there are other plastination techniques available where we can look for specific anatomical structures through the thickness of the tissue. These techniques include sectioning and grinding of plastinated tissue blocks or thick slices. The ultra‐thin E12 technique, unlike the classic E12 technique, starts with the plastination of a large tissue block. High temperatures (30–60°C) facilitate the vacuum‐forced impregnation by decreasing the viscosity of the E12 and increasing the vapour pressure of the intermediary solvent. By sectioning the cured tissue block with a diamond band saw plastinated sections with a thickness of <300 μm can be obtained. The thickness of plastinated sections can be further reduced by grinding. Resulting sections of <100 µm are suitable for histological staining and microscopic studies. Anatomical structures of interest in thick plastinate slices can be followed by variable manual grinding in a method referred to as Tissue Tracing Technique (TTT). In addition, the tissue thickness can be adapted to the transparency or darkness of tissue types in different regions of the same plastinated section. The aim of this study was to evaluate the advantages of techniques based on sectioning and grinding of plastinated tissue (E12 ultra‐thin and TTT) compared to conventional sheet‐forming techniques (E12). 相似文献
19.
Formation of modified fatty acids and oxyphytosterols during refining of low erucic acid rapeseed oil 总被引:4,自引:0,他引:4
Lambelet P Grandgirard A Gregoire S Juaneda P Sebedio JL Bertoli C 《Journal of agricultural and food chemistry》2003,51(15):4284-4290
Formation of trans fatty acids and cyclic fatty acid monomers was investigated during refining of low erucic acid rapeseed oil. The first steps of the refining process, that is, degumming, neutralization, and bleaching, hardly modified the fatty acid profile. In contrast, deodorization produced substantial quantities of trans fatty acids (>5% of total fatty acids) and small amounts of cyclic fatty acid monomers (650 mg of cyclic fatty acid monomers/kg of oil) when severe conditions (5-6 h at 250 degrees C) were used. Alpha-linolenic acid was the main precursor of cyclic fatty acid monomers. The influence of deodorization on the chemical composition of low erucic acid rapeseed oil was studied additionally. Whereas free fatty acids, peroxides, and tocopherols decreased, neither total polar compounds nor oxyphytosterols changed during deodorization. Oxyphytosterols were identified by GC-MS. Three oxyphytosterols not yet observed in oil were tentatively identified as 6beta-hydroxycampestanol, 6beta-hydroxysitostanol, and 6beta-hydroxybrassicastanol. Brassicasterol oxides were the most abundant oxyphytosterols. 相似文献
20.
Stanca L Petrache SN Radu M Serban AI Munteanu MC Teodorescu D Staicu AC Sima C Costache M Grigoriu C Zarnescu O Dinischiotu A 《Fish physiology and biochemistry》2012,38(4):963-975
Silicon-based quantum dots were intraperitoneally injected in individuals of Carassius auratus gibelio. Their effects on white muscle were investigated by following their distribution and impact on the antioxidative system. The GSH level significantly increased after 1 and 3?days of exposure by, respectively, 85.3 and 25.4%. Seven days later, GSH levels were similar to control concentrations. MDA concentration rose after three days by 46.9% and remained at the same level after 7?days. Protein thiol levels significantly decreased by 6.7 and 8.1% after 3 and 7?days, whereas advanced oxidation protein products increased by 12.7, respectively, 28.1% in the same time intervals. The protein reactive carbonyl groups were raised only after the first day of exposure and returned to the control level later on. SOD specific activity increased up to 48% after 7?days, while CAT activity increased by 328, 176, and 26% after 1, 3, and 7?days of treatment. GST specific activity was up-regulated by 87, 18, and 9%, while GR activity increased by 68, 34, and 9%. G6PD activity was up-regulated by 12, 22, and 50%, whereas GPx activity raised by 75 and 109% compared to control after, respectively, 1, 3, and 7?days. Our results suggest that oxidative stress induced by silicon-based quantum dots was not strong enough to cause permanent damage in the white muscle of crucian carp. 相似文献