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691.
Humberto R. Silva Patrick E. Phelan Jay S. Golden 《International journal of biometeorology》2010,54(1):13-22
A zero-dimensional energy balance model was previously developed to serve as a user-friendly mitigation tool for practitioners
seeking to study the urban heat island (UHI) effect. Accordingly, this established model is applied here to show the relative
effects of four common mitigation strategies: increasing the overall (1) emissivity, (2) percentage of vegetated area, (3)
thermal conductivity, and (4) albedo of the urban environment in a series of percentage increases by 5, 10, 15, and 20% from
baseline values. In addition to modeling mitigation strategies, we present how the model can be utilized to evaluate human
health vulnerability from excessive heat-related events, based on heat-related emergency service data from 2002 to 2006. The
24-h average heat index is shown to have the greatest correlation to heat-related emergency calls in the Phoenix (Arizona,
USA) metropolitan region. The four modeled UHI mitigation strategies, taken in combination, would lead to a 48% reduction
in annual heat-related emergency service calls, where increasing the albedo is the single most effective UHI mitigation strategy. 相似文献
692.
The pulmonate land snail, Rumina decollata, is a highly invasive gastropod adapted to arid conditions, and native from the Mediterranean area. It was recorded for the
first time in Argentina in 1988, in the northeastern Pampas of the Buenos Aires Province, a region characterized by a humid
mesothermal climate with no water deficit. In the present contribution, we report the finding of populations of this species
in the semiarid region of La Pampa and Mendoza provinces in central-western Argentina. The present findings extend the invasive
distributional range of R. decollata westwards through more than 1000 km from the site where it was detected in 1988. Although no damages to agricultural areas
have been reported to the moment in Argentina, the presence of R. decollata in semiarid areas warns us about its potential as an important plague in the future. 相似文献
693.
Jairo Mu oz-Delgado Hector P rez-Rinc n Humberto Nicolini Jos Cort s Jos Garcí a-Marí n Francesca Munda Ana Marí a Santill n-Doherty Hector Alejandro Ortega-Soto 《Biological Rhythm Research》2003,34(5):485-492
The relationship between seasonal changes and mental disorders has been extensively studied in the northern and southern hemispheres. In both cases, the results show that there is a higher rate of schizophrenic births during the winter months. The present study attempts to prove the existence of this phenomena in Mexico City, an area that does not undergo extreme weather variations throughout the year. A total of 2,288 schizophrenic patients was considered for this study. Their date of birth was compared to that of the general population of the Mexico City area, a total of 4,848,119 individuals. The number of births was evaluated according to the number of days in each month. The distribution of the births of schizophrenics was compared to the reference population by means of a Kolmogorov-Smirnov test and a X 2 contrast. The annual rhythm of births of schizophrenics was determined through an analysis of the Estimated Seasonal Component. There was a slight, non-significant increment in schizophrenic births in December and autumn, as compared with the general population birth rate. Interestingly, it was found that births in the control population decreased significantly in December when compared with all the other months. Results were discussed in relation to the geographical location of Mexico, which lies in a tropical zone, and as a consequence minimal seasonal effects. 相似文献
694.
Humberto J. Silva María Cristina Italiano Susana G. Ferrari 《Biotechnology Techniques》1994,8(12):889-894
The biomass production of a cyanobacterium (Nostoc sp.) in a photoreactor with a low illuminated surface area to volume ratio was improved by the reutilization of the culture
medium. After six succesive utilizations the growth ofNostoc sp. amounted to 2.15 g/l with an average content in phycobiliproteins of 14.4% on dry weight basis. The procedure reported
allowed an 80% increase in biomass. The cellular self-sedimentation proved to be effective for biomass separation between
reutilization steps. 相似文献