Fire and restoration of the largest urban forest of the world in Rio de Janeiro City,Brazil

National Park of Tijuca in Rio de Janeiro (Brazil) is about 3,300 ha and considered the largest urban forest in the world. Its floristic composition is typical of Atlantic Rain Forest. The reserve is being altered because of fire occurrences and urban expansion. This study identified locations and causes of forest fires, and makes management recommendations to restore damaged areas. From 1991 to 2000, forest firefighters recorded an average of 75-fire occurrences/year. Identified causes included hot air balloons (24%), intentional (24%), rubbish burning (21%) and religious practices (17%). Primary fuels included invasive grasses and ferns. Although hot air balloons destroyed larger areas of forest in each occurrence, a greater number of fires started in the invasive vegetation along roads that bisect the forest. In response to recurrent forests, invasive vegetation has spread gradually into the forest increasing forest degradation. To decrease fire damage, sites with high fire frequencies and density of invasive vegetation were planted with less flammable species. Results indicate that fire frequency decreased and density of invasive vegetation declined. This approach appears to prevent fire incidence, reduce the need for fire fighting, and preserve existing biodiversity.     

改善开发所致移民安置项目的后果——牛津大学难民研究中心研究成果报告

论文在讨论四个移民典型案例的基础上 ,讨论在项目中与政策相关的教训     

Computing maximum likelihood estimates from type II doubly censored exponential data

It is well-known that, under Type II double censoring, the maximum likelihood (ML) estimators of the location and scale parameters, θ and δ, of a twoparameter exponential distribution are linear functions of the order statistics. In contrast, when θ is known, theML estimator of δ does not admit a closed form expression. It is shown, however, that theML estimator of the scale parameter exists and is unique. Moreover, it has good large-sample properties. In addition, sharp lower and upper bounds for this estimator are provided, which can serve as starting points for iterative interpolation methods such as regula falsi. Explicit expressions for the expected Fisher information and Cramér-Rao lower bound are also derived. In the Bayesian context, assuming an inverted gamma prior on δ, the uniqueness, boundedness and asymptotics of the highest posterior density estimator of δ can be deduced in a similar way. Finally, an illustrative example is included.     

Form Perception of Partly Occluded Shapes in 4‐Month‐Old Infants

Two habituation experiments were conducted to investigate how 4‐month‐old infants perceive partly occluded shapes. In the first experiment, we presented a simple, partly occluded shape to the infants until habituation was reached. Then we showed either a probable completion (one that would be predicted on the basis of both local and global cues) or an improbable completion. Longer looking times were found for the improbably completed shape (compared to probable and control conditions), suggesting that the probable shape was perceived during partial occlusion. In the second experiment, infants were habituated to more ambiguous partly occluded shapes, where local and global cues would result in different completions. For adults, the percept of these shapes is usually dominated by global influences. However, after habituation the infants looked longer at the globally completed shapes. These results suggest that by the age of 4 months, infants are able to infer the perceptual completion of partly occluded shapes, but for more ambiguous shapes, this completion seems to be dominated by local influences.     

Demographic Shifts in the Czech Republic after 1989: A Second Demographic Transition View

A dramatic change in fertility,family formation and living arrangements tookplace in the Czech Republic over the 1990s. Theestablishment of democracy, profound socialtransformation and transition to the marketeconomy affected the values and demographicbehaviour of the young Czech generation. Thispaper examines whether these demographic shiftscan be interpreted within the framework of thesecond demographic transition. The theoreticalpart discusses the idea of the transition,outlining three distinctive conceptualisations.Two of them – the view of the transition as aprogression of characteristic interrelateddemographic changes and a broader viewstressing the importance of underlyingideational factors – fit the Czech situationvery well. A comparison with the Netherlandsreveals that the onset of the transition in theCzech Republic may be clearly located in thefirst half of the 1990s, lagging two decadesbehind the Netherlands.     

It takes two to tango: the integration of people with disabilities into society

The concept of integration is not well defined. It not known how people with disabilities experience integration. In this study qualitative methods were used. The aim of the article is to define a model of successful integration based on the perspectives of people with disabilities and people within their social environment. Integration consists of five elements: functioning ordinarily without receiving special attention, mixing with others that are not disabled, taking part in society, trying to realize one’s potential and directing one’s own life. Integration is obtained through a process of interaction between a person with a disability and society. This process is influenced by personal, societal and support factors. The individual with a disability and society have a mutual responsibility with respect to integration.     

价值观的形成规律与当代青年价值观现状

价值观的形成有其自身的规律 ,并受到社会因素和个体内在因素的影响。当代青年正处在我国改革开放进一步深化和社会主义市场经济体制逐步确立及自我意识发展和自我需要扩大的时期 ,因此 ,他们的价值观必然打着当今时代的烙印 ,具有开放性、先锋化、情绪性等特点 ,他们追求高效、公正、互利 ,追求求职与成才相结合 ,但同时 ,其自身的身心失范问题也日趋严重。     

马寅初的人口质量观及其现实意义——纪念马寅初诞辰120周年

注重人口质量是马寅初人口思想对马尔萨斯人口论的实质性超越.马寅初关于人口质量的观点主要体现于:人口质量与人口数量是对立的统一;在新时代,人不在乎多,而在乎精;人口质量的提高是德、智、体全面的提高和全民的提高;提高人口质量不能离开本国国情.在现代化进程中我们重温马寅初关于提高人口质量方面的有关观点和主张,有助于我们处理好提高人口质量与稳定低生育水平、保护资源环境、提高农民收入等方面的关系.