5 resultados para Comparison with optical model calculations using the Sao Paulo potential and other data
em Digital Commons at Florida International University
Resumo:
Changes in the demographic structure of American families have highlighted the need to reevaluate fatherhood. Research illustrates that paternal involvement positively affects child development, but father absence has increased due to rising rates of divorce, cohabitation, and non-marital childbirth. There is evidence that other male figures can function as effective father surrogates. However, information is limited, particularly with respect to female development. ^ This study examined differences in well-being, achievement, and paternal support among girls in four father categories: (a) Biological Father, (b) Step-Father, (c) Surrogate Father, and (d) No Father. Maternal support, economic hardship, and life stressors were included as potential covariates. Interviews were conducted with an ethnically and economically diverse sample of 694 sixth and eighth grade children. The sample included boys to assess the extent to which the findings were unique to girls. Measures included quantitative and qualitative support from father figures and indices of self-esteem, loneliness, and depression. Standardized test scores and classroom grades were also obtained from school records. ^ Girls with biological fathers had higher achievement test scores than girls in the other father categories, but there were no other differences related to the presence or absence of a father-figure. Biological fathers also provided greater quantitative and qualitative support than step- and surrogate fathers. Surrogate fathers provided a greater amount but lower quality of support than step-fathers. ^ Girls who received lower levels of support from biological fathers reported lower self-esteem and greater loneliness, compared to fatherless girls and those receiving low support from other father figures, suggesting that low support from biological fathers may be especially distressing. On the other hand, girls with low biological father support had higher achievement scores compared to fatherless girls and those who received low support from step- and surrogate fathers. Thus, the mere presence of the biological father appears to facilitate achievement, regardless of the level of support he provides. ^ This study highlights the supportive characteristics of different father figures and their influence on well-being and achievement in females. Future research should focus on the dynamics of surrogate father relationships and the specific characteristics that differentially affect developmental outcomes. ^
Resumo:
Research with adult samples has identified a cognitive risk factor for the development of panic and other anxiety disorders in the concept of anxiety sensitivity. The research to date on anxiety sensitivity in children, using the Childhood Anxiety Sensitivity Index (CASI), suggests that the CASI may help to garner knowledge regarding the development of anxiety sensitivity and also help to understand the development of panic attacks, panic disorder and other anxiety disorders in youth. To examine the development of anxiety sensitivity and its relation to panic in youth, data were collected on 44 children in 1998 who were administered the CASI in 1991. Results indicated that children whose CASI scores increased from Time 1 to Time 2 were significantly more likely to report experiencing panic attacks than children whose CASI scores decreased from Time 1 to Time 2. Specifically, 64% (9/14) of children whose CASI scores increased from Time 1 to Time 2 reported having one or more panic attacks versus 36% (5/14) reported having none. Moreover, 72% (21/29) of children whose CASI scores decreased from Time 1 to Time 2 reported no panic attacks. These results suggest that childhood may be the time when anxiety sensitivity as a risk factor for panic and panic disorder is developing. Results are discussed in terms of their relevance for understanding the development of panic and the need for further research to determine the generalizability of these findings in larger samples of children followed over different time spans. ^
Resumo:
We briefly review the nature of light and its effects on plants, and then describe an inexpensive experimental system for studying the effects of shade, specifically the contributions of reduced intensity ("quantity") and the altered spectral distribution of foliage shade ("quantity") on the development of seedlings and other plants. This system has been devised to be safe to construct, inexpensive in its use of readily available materials, and appropriate for a range of student grade levels, from ~grade six to university courses in botany. We conclude by suggesting a range of experiments this system will allow. An advantage of this system is that it promotes the study of the responses of a large range of plants, most completely unstudied for these responses.
Resumo:
For the first time in more than fifty years, the domestic and external conflicts in Latin America and the Caribbean (LAC) are not primarily ideological in nature. Democracy continues to thrive and its promise still inspires hope. In contrast, the illegal production, consumption, and trading of drugs – and its links to criminal gangs and organizations – represent major challenges to the region, undermining several States’ already weak capacity to govern. While LAC macroeconomic stability has remained resilient, illegal economies fill the region, often offering what some States have not historically been able to provide – elements of human security, opportunities for social mobility, and basic survival. Areas controlled by drug trafficking organizations (DTOs) are now found in Central America, Mexico, and the favelas of Rio de Janeiro and São Paulo, reflecting their competition for land routes and production areas. Cartels such as La Familia, Los Zetas, and Primeiro Comando da Capital (PCC-Brazil), among others, operate like trade and financial enterprises that manage millions of dollars and resources, demonstrating significant business skills in adapting to changing circumstances. They are also merciless in their application of violence to preserve their lucrative enterprises. The El Salvador-Guatemala-Honduras triangle in Central America is now the most violent region in the world, surpassing regions in Africa that have been torn by civil strife for years. In Brazil’s favelas and Guatemala’s Petén region, the military is leaving the barracks again; not to rule, however, but to supplement and even replace the law enforcement capacity of weak and discredited police forces. This will challenge the military to apply lessons learned during the course of their experience in government, or from the civil wars that plagued the region for nearly 50 years during the Cold War. Will they be able to conduct themselves according to the professional ethics that have been inculcated over the past 20 years without incurring violations of human rights? Belief in their potential to do good is high according to many polls as the Armed Forces still enjoy a favorable perception in most societies, despite frequent involvement in corruption. Calling them to fight DTOs, however, may bring them too close to the illegal activities they are being asked to resist, or even rekindle the view that only a “strong hand” can resolve national troubles. The challenge of governance is occurring as contrasts within the region are becoming sharper. There is an increasing gap between nations positioned to surpass their “developing nation” status and those that are practically imploding as the judicial, political and enforcement institutions fall further into the quagmire of illicit activities. Several South American nations are advancing their political and economic development. Brazil in particular has realized macro-economic stability, made impressive gains in poverty reduction, and is on track to potentially become a significant oil producer. It is also an increasingly influential power, much closer to the heralded “emerging power” category that it aspired to for most of the 20th century. In contrast, several Central American States have become so structurally deficient, and have garnered such limited legitimacy, that their countries have devolved into patches of State controlled and non-State-controlled territory, becoming increasingly vulnerable to DTO entrenchment. In the Caribbean, the drug and human trafficking business also thrives. Small and larger countries are experiencing the growing impact of illicit economies and accompanying crime and violence. Among these, Guyana and Suriname face greater uncertainty, as they juggle both their internal affairs and their relations with Brazil and Venezuela. Cuba also faces new challenges as it continues focusing on internal rather than external affairs and attempts to ensure a stable leadership succession while simultaneously trying to reform its economy. Loosening the regime’s tight grip on the economy while continuing to curtail citizen’s civil rights will test the leadership’s ability to manage change and prevent a potential socio-economic crisis from turning into an existential threat. Cuba’s past ideological zest is now in the hands of Venezuela’s President Hugo Chavez, who continues his attempts to bring the region together under Venezuelan leadership ideologically based on a “Bolivarian” anti-U.S. banner, without much success. The environment and natural disasters will merit more attention in the coming years. Natural events will produce increasing scales of destruction as the States in the region fail to maintain and expand existing infrastructure to withstand such calamities and respond to their effects. Prospects for earthquakes, tsunamis, and hurricanes are high, particularly in the Caribbean. In addition, there are growing rates of deforestation in nearly every country, along with a potential increase in cross-sector competition for resources. The losers might be small farmers, due to their inability to produce quantities commensurate to larger conglomerates. Regulations that could mitigate these types of situations are lacking or openly violated with near impunity. Indigenous and other vulnerable populations, including African descendants, in several Andean countries, are particularly affected by the increasing extraction of natural resources taking place amongst their terrain. This has led to protests against extraction activities that negatively affect their livelihoods, and in the process, these historically underprivileged groups have transitioned from agenda-based organization to one that is bringing its claims and grievances to the national political agenda, becoming more politically engaged. Symptomatic of these social issues is the region’s chronically poor quality of education that has consistently failed to reduce inequality and prepare new generations for jobs in the competitive global economy, particularly the more vulnerable populations. Simultaneously, the educational deficit is also exacerbated by the erosion of access to information and freedom of the press. The international panorama is also in flux. New security entities are challenging the old establishment. The Union of South American Nations, The South American Defense Council, the socialist Bolivarian Alliance, and other entities seem to be defying the Organization of American States and its own defense mechanisms, and excluding the U.S. And the U.S.’s attention to areas in conflict, namely Iraq, Afghanistan, and Pakistan – rather than to the more stable Latin America and Caribbean – has left ample room for other actors to elbow in. China is now the top trading partner for Brazil. Russian and Iran are also finding new partnerships in the region, yet their links appear more politically inclined than those of China. Finally, the aforementioned increasing commercial ties by LAC States with China have accelerated a return to the preponderance of commodities as sources of income for their economies. The increased extraction of raw material for export will produce greater concern over the environmental impact that is created by the exploitation of natural resources. These expanded trade opportunities may prove counterproductive economically for countries in the region, particularly for Brazil and Chile, two countries whose economic policies have long sought diversification from dependence on commodities to the development of service and technology based industries.
Resumo:
In the 1980s, government agencies sought to utilize research on drug use prevention to design media campaigns. Enlisting the assistance of the national media, several campaigns were designed and initiated to bring anti-drug use messages to adolescents in the form of public service advertising. This research explores the sources of information selected by adolescents in grades 7 through 12 and how the selection of media and other sources of information relate to drug use behavior and attitudes and perceptions related to risk/harm and disapproval of friends' drug-using activities.^ Data collected from 1989 to 1992 in the Miami Coalition School Survey provided a random selection of secondary school studies. The responses of these students were analyzed using multivariate statistical techniques.^ Although many of the students selected media as the source for most of their information on the effects of drugs on the people who use them, the selection of media was found to be positively related to alcohol use and negatively related to marijuana use. The selection of friends, brothers, or sisters was a statistically significant source for adolescents who smoke cigarettes, use alcohol or marijuana.^ The results indicate that the anti-drug use messages received by students may be canceled out by media messages perceived to advocate substance use and that a more persuasive source of information for adolescents may be friends and siblings. As federal reports suggest that the economic costs of drug abuse will reach an estimated $150 billion by 1997 if current trends continue, prevention policy that addresses the glamorization of substance use remains a national priority. Additionally, programs that advocate prevention within the peer cluster must be supported, as peers are an influential source for both inspiring and possibly preventing drug use behavior. ^