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981.
982.
Johnson N. Nkem Olufunso A. Somorin Cyprian Jum Monica E. Idinoba Youssoufa M. Bele Denis J. Sonwa 《Mitigation and Adaptation Strategies for Global Change》2013,18(5):513-533
The livelihood strategies of indigenous communities in the Congo Basin are inseparable from the forests, following their use of forest ecosystem goods and services (FEGS). Climate change is expected to exert impacts on the forest and its ability to provide FEGS. Thus, human livelihoods that depend on these FEGS are intricately vulnerable to climate impacts. Using the livelihood strategies of the two main forest indigenous groups; the Bantus and Pygmies, of the high forest zone of southern Cameroon; this paper examines the nature and pattern of their vulnerability to different climate risks as well as highlights how place of settlement in the forest contributes to the vulnerability of people in forest systems. Forests provide different capitals as FEGS and make direct and indirect contributions to livelihoods which are exploited differently by the two indigenous groups. The results show that vulnerability of forest communities is structured by lifestyle, culture and the livelihood strategies employed which are largely shaped by the place of settlement in the forest. The Pygmies living within the forests are engaged in nomadic gathering and foraging of non-timber forest resources. The Bantus prefer forest margins and are mostly preoccupied with sedentary farming, using the forest as additional livelihood opportunity. The contrasting lifestyles have implications on their vulnerability and adaptation to climate impacts which need to be taken into considerations in planning and implementation of national climate change adaptation strategies. 相似文献
983.
Margaret E. M. Tolbert Johnson A. Kamalu Garnette D. Draper 《Journal of environmental science and health. Part. B》2013,48(5):575-585
Abstract The effects of divalent cations on gluconeogenesis in enzy‐matically isolated rat hepatic parenchymal cells were examined. Cadmium, zinc and copper decreased glucose production from lactate (10 mM). However, manganese at 0.05 to 1.0 mM levels stimulated gluconeogenesis by the cells and reduced the effects of the Cd+2, Zn+2 and Cu+2 on gluconeogenesis. The results indicate that under these in vitro conditions the cations altered an aspect of hepatic function—gluconeogenesis from lactate. 相似文献
984.
B. D. Hill D. J. Inaba D. L. Johnson 《Journal of environmental science and health. Part. B》2013,48(5):601-617
Abstract The mean amount of deltamethrin deposited on natural substrates (i.e., soil and vegetation) in three experiments was 63, 73, and 76% of applied. Composite samples taken from 16 sites/replicate gave representative and repeatable measures of deposition. The use of Teflon discs as artificial targets to measure aerial deposition was investigated. The discs had only 34–71% mean trapping efficiency for the spray droplets. Deposition was quite variable among different sampling sites within a field (CV=73–83%). Much of this variation was caused by irregular overlapping of spray swaths. 相似文献
985.
W.B. Johnson F.L. Ludwig W.F. Dabberdt R.J. Allen 《Journal of the Air & Waste Management Association (1995)》2013,63(6):490-498
A relatively simple Gaussian-type diffusion simulation model for calculating urban carbon monoxide (CO) concentrations as a function of local meteorology and the distribution of traffic is described. The model can be used in two ways: (1) in the synoptic mode, in which hourly concentrations at one or many receptor points are calculated from historical or forecast traffic and meteorological data; and (2) in the climatological mode, in which concentration frequency distributions are calculated on the basis of long-term sequences of input data. For model evaluation purposes, an extensive field study involving meteorological and air-quality measurements was conducted during November-December 1970 in San Jose, Calif., which has an automated network to provide traffic data throughout the central business district. Model refinements made on the basis of the data from this experimental program include the addition of a street-canyon submodel to compensate for the important aerodynamic effects of buildings on CO concentrations at streetside receptors. The magnitude of these effects was underscored by the concentrations measured on opposite sides of the street in San Jose, which frequently differed by a factor of two or more. Evaluation of the revised model has shown that calculated and observed concentration frequency distributions for street-canyon sites are in good agreement. Hour-average predictions are well correlated with observations (correlation coefficient of about 0.6 to 0.7), and about 80 percent of the calculated values are within 3 ppm of the observed hour-average concentrations, which ranged as high as 16 ppm. 相似文献
986.
987.
Alireza A. Shamshirsaz Ramen H. Chmait Julien Stirnemann Mounira A. Habli Anthony Johnson Kamran Hessami Shayan Mostafaei Ahmed A. Nassr Roopali V. Donepudi Magdalena Sanz Cortes Jimmy Espinoza Eyal Krispin Michael A. Belfort 《黑龙江环境通报》2023,43(1):72-83
This meta-analysis aims to compare the perinatal outcome of twin-twin transfusion syndrome (TTTS) pregnancies undergoing selective versus vascular equator (Solomon) fetoscopic laser photocoagulation (FLP). We performed a systematic search in PubMed and Web of Science from inception up to 25 July 2021. Studies comparing the Solomon and selective techniques of FLP for treatment of TTTS pregnancies were eligible. Random-effects or fixed-effect models were used to pool standardized mean differences (SMD) and log odds ratio. Seven studies with a total of 1664 TTTS pregnancies (n = 671 undergoing Solomon and n = 993 selective techniques) were included. As compared to the selective FLP, Solomon was associated with a lower risk of recurrent TTTS compared to the selective technique (Log odds ratio [OR]: −1.167; 95% credible interval [CrI]: −2.01, −0.33; p = 0.021; I2: 67%). In addition, Solomon was significantly associated with a higher risk of placental abruption than the selective technique (Log [OR]: 1.44; 95% CrI: 0.45, 2.47; p = 0.012; I2: 0.0%). Furthermore, a trend for the higher risk of preterm premature rupture of membranes was observed among those undergoing Solomon (Log [OR]: 0.581; 95% CrI: −0.43, 1.49; p = 0.131; I2: 17%). As compared to selective FLP, the Solomon technique for TTTS pregnancies is associated with a significantly lower recurrence of TTTS; however, it significantly increases the risk of placental abruption. 相似文献