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1.
Leong Shing Tet Muttamara S. Laortanakul Preecha 《Water, air, and soil pollution》2001,131(1-4):41-60
This study investigated the relationship between exhaust emission from motorcycles and ambient air quality in Bangkok Metropolitan Region (BMR). The test result revealed that averagepollutant concentrations of the test motorcycles in terms of hydrocarbon, carbon monoxide and nitrogen dioxide were 8.38, 16.69 and 0.04 g km-1, respectively. The finding also indicated that two-stroke motorcycles emitted 1.5 and 5 times more carbon monoxide and hydrocarbon emission, respectively perkilometer driven than do four-stroke motorcycles. Four air sampling stations were strategically established to evaluate the air pollution problems in Bangkok arising from vehicle exhaust emission. Investigation was carried out to determine the correlation between average air pollutant concentration with different traffic configuration in each traffic zone of Bangkok Metropolitan Region (BMA) during peak/non peak hours, day/night times and weekday/weekend. The average concentrationsof PM10 particulate matter, carbon monoxide, nitrogen dioxide and sulphur dioxide in Bangkok street air were found tobe 84.33 μg m-3 (24 hr ave.), 7.05 mg m-3 (8 hr ave.), 56.74 μg m-3 (1 hr ave.) and 9.60 μg m-3 (24 hr ave.), respectively. 相似文献
2.
Heparin affinity: purification of a tumor-derived capillary endothelial cell growth factor 总被引:73,自引:0,他引:73
Y Shing J Folkman R Sullivan C Butterfield J Murray M Klagsbrun 《Science (New York, N.Y.)》1984,223(4642):1296-1299
A tumor-derived growth factor that stimulates the proliferation of capillary endothelial cells has a very strong affinity for heparin. This heparin affinity makes it possible to purify the growth factor to a single-band preparation in a rapid two-step procedure. The purified growth factor is a cationic polypeptide, has a molecular weight of about 18,000, and stimulates capillary endothelial cell proliferation at a concentration of about 1 nanogram per milliliter. 相似文献
3.
To improve the productivity and wood quality of poplar plantations, effects of four planting spacing on canopy characteristics, biomass production and stem roundness in poplar plantations were evaluated over 8 years. Planting spacing influenced canopy characteristics of the plantations, and further affected the understory vegetation and plantation productivity. Understory vegetation biomass and Shannon-Wiener index were negatively correlated with leaf area index, but both diversity indexes and aboveground biomass of understory vegetation were higher in stands with a wider spacing. Tree diameter growth increased with increasing planting spacing, while the increment in plantations of square configurations (5?×?5 m and 6?×?6 m) was higher than those with rectangular configurations (3?×?8 m, 4.5?×?8 m). The highest poplar biomass production was achieved in the plantation with 5?×?5 m spacing at age 8. Moreover, poplar trees showed a tendency with better stem roundness in a square configuration. The results suggest that planting spacing not only affect canopy characteristics, understory vegetation and tree growth but also wood quality, and square configurations (5?×?5 m and 6?×?6 m) could be a better option for poplar plywood timber production at similar sites. 相似文献
4.
Luzia Rast Shing Lee Sonevilay Nampanya Jenny-Ann L. M. L. Toribio Syseng Khounsy Peter A. Windsor 《Tropical animal health and production》2013,45(2):539-546
This study was completed to determine the prevalence and distribution of Toxocara vitulorum infection in cattle and buffalo calves and investigate its clinical impact in northern Lao PDR (Peoples Democratic Republic). The results aim to assist decisions on disease control measures that can contribute to increasing cattle and buffalo productivity within smallholder farming systems in tropical areas. A prevalence survey for T. vitulorum in buffalo and cattle calves aged <3 months was conducted between September 2009 and June 2010 in five provinces of northern Lao PDR using a two-stage sampling technique to select 69 villages and 899 calves, with faecal samples collected and examined for T. vitulorum eggs at a local laboratory. At the time of sampling, data on calf morbidity and anthelmintic treatment was also collected. Factors potentially associated with infection and severity of infection were analyzed at univariable and multivariable levels, using T. vitulorum status (positive/negative) and on the positive calves only, faecal egg count levels as outcome variables. The estimated prevalence of T. vitulorum in northern Lao was 22.6 % (95 % confidence interval [CI], 0.17–0.28), and 76.8 % of villages had at least one positive calf. Province was the only significant (p?<?0.05) variable investigated associated with calf infection status. Species (buffalo) was the only variable significantly (p?<?0.05) associated with higher egg per gram of faeces levels among infected calves. Prevalence in calves aged 1–21 days, the reported prepatent period, was 17.5 % (CI 0.11–0.24). Treatment levels were very low (8.2 %) and if treatment occurred it was mostly unsuccessful. The high and wide spread infection of T. vitulorum in cattle and buffalo calves identified in this survey is likely to result in suboptimal cattle and buffalo productivity. Improved management of T. vitulorum infection in cattle and buffalo calves in northern Lao PDR is indicated to reduce potential negative production impacts and enable more efficient development of large ruminant livestock industry as a pathway from rural poverty for smallholder farmers in northern Lao PDR. In addition to quantifying this disease problem in calves, the conduct of this applied participatory research study provided an important opportunity to improve animal health services by increasing the parasite, large ruminant handling and research knowledge and capacity of government animal health staff and farmers. 相似文献
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This paper takes issue with the desakota model developed by Terry McGee by elucidating the illegal land use and construction in the rural–urban transition zone in China, with the additional case study of Tianhe Village in Guangzhou City. The paper emphasises the need to examine the geography of illegal activities along the approach of geographies of difference. It has shown that illegal land use and construction is prevalent in rural China. In rural areas where cultivated land has been converted to non‐agricultural purposes, peasants are left with no alternative but to use land and construct buildings illegally. Some have increased their income by leasing out flats to migrant workers, whereas others have not been able to do this. This study has revealed that underneath the positive and integrative picture portrayed by the desakota model is its negative and disintegrative counterpart. Illegal land use and construction is one such example. Unless we incorporate both into our studies, we will not be able to comprehend the urban morphology of Chinese city regions in the new millennium. 相似文献
7.
Parkpian Preeda Leong Shing Tet Laortanakul Preecha Torotoro Josephine L. 《Water, air, and soil pollution》2002,139(1-4):43-60
This study was conducted to assess the potential of Bangkoksewage sludge for amendment of saline and acidic soil withrespect to heavy metal mobilization. Experiments were carriedout at six levels of salinity (with electrical conductivityvalues of 2, 4, 8, 19, 31 and 42 dS m-1) and two levels ofacidity (with pH values of 5 and 6). A pure sludge sample was used as a control system. Subsamples were collected andanalyzed for total and bioavailable heavy metals. Three sets ofsoil-sludge mixture were prepared using different weight ratio(1:1, 4:1 and 10:1) to simulate the conditions in the field withsludge-amended soil. Samples of soil-sludge mixture were incubated for 4 weeks to stabilize organic substances. Themobility and concentration of bioavailable heavy metal invarying soil-sludge mixture ratio with different electricalconductivity (EC) values were evaluated with the use of DTPA(diethylenetriamine pentaacetric acid) extraction techniques.Pure saline soil sample from Sakhon Nakhon (North-eastern partof Thailand) was used of salt-heavy metal interactions on thegermination percentage in soil mixed with sludge and to screencrops or varieties for their tolerances to soil salinity. Seventypes of seeds – mung bean, corn, soybean, tomato, stringbean, sunflower and marigol – were planted in each of the threesoil-sludge mixtures (1:1, 4:1 and 10:1) with different salinitylevels. Seedlings were monitored by counting the number of seeds thatare germinated and seed germination percentage can be used as anindicator for the level of salinity unsuitable for plant growth. 相似文献
8.
2003-2005年对海南岛沿海越冬水鸟进行了调查,旨在加强海南岛湿地的保护和管理.在调查的20个湿地中,共记录水鸟68种,新发现3处全球濒危鸟类黑脸琵鹭(Platalea minor)的越冬地,即临高后水湾、东方北黎湾和三亚河.2003-2009年冬季对黑脸琵鹭的越冬种群进行了持续调查.海南岛越冬水鸟数量最多的是鹭鸟,其次是鸻鹬类和鸥类.分析发现,在有红树林分布的湿地鸟类种数和个体数量均比无红树林分布的湿地明显增加.此外,博浦湾、黄龙港、后水湾、洋浦港、北黎湾、莺歌海、三亚河、清澜港和东寨港等地是海南岛鸟类优先保护的湿地,其人为干扰应该被禁止. 相似文献
9.
Huang CF Chen YW Yang CY Lin HY Way TD Chiang W Liu SH 《Journal of agricultural and food chemistry》2011,59(4):1087-1094
The effect of lotus leaf ( Nelumbo nucifera Gaertn.) on diabetes is unclear. We hypothesized that lotus leaf can regulate insulin secretion and blood glucose levels. The in vitro and in vivo effects of lotus leaf methanolic extract (NNE) on insulin secretion and hyperglycemia were investigated. NNE increased insulin secretion from β cells (HIT-T15) and human islets. NNE enhanced the intracellular calcium levels in β cells. NNE could also enhance phosphorylation of extracellular signal-regulated protein kinases (ERK)1/2 and protein kinase C (PKC), which could be reversed by a PKC inhibitor. The in vivo studies showed that NNE possesses the ability to regulate blood glucose levels in fasted normal mice and high-fat-diet-induced diabetic mice. Furthermore, the in vitro and in vivo effects of the active constituents of NNE, quercetin, and catechin, on glucose-induced insulin secretion and blood glucose regulation were evaluated. Quercetin did not affect insulin secretion, but catechin significantly and dose-dependently enhanced insulin secretion. Orally administered catechin significantly reversed the glucose intolerance in high-fat-diet-induced diabetic mice. These findings suggest that NNE and its active constituent catechin are useful in the control of hyperglycemia in non-insulin-dependent diabetes mellitus through their action as insulin secretagogues. 相似文献
10.
海南俄贤岭及周边地区鸟类调查报告,含一海南省新记录 总被引:1,自引:0,他引:1
我们于1998年4月、2005年8月及2007年3月,分别3次对俄贤岭及周边地区鸟类资源开展调查.共记录鸟类119种,分别隶属于12目33科;当中包括1个海南新记录,即黄头扇尾莺Cisticola exilis.俄贤岭及周边地区共有27种鸟类被列入不同保护或濒危名录,占本调查鸟类记录总数的22.7%. 其中国家重点I级保护物种2种,他们是海南山鹧鸪Arborophila ardens和海南孔雀雉Polyplectron katsumatae,另外23种是国家重点II级保护物种.被列入中国红色名录的有11种,其中濒危2种、易危8种及近危2种.IUCN红色名录2种,其中易危1种及近危1种.调查还发现已知海南最大种群的戈氏金丝燕Collocalia germani,戈氏金丝燕在中国已经极度濒危,俄贤岭地区是我国保护这物种的最关键地区. 相似文献