AIDS Scientists Research Articles

Characterizing natural convection and thermal behavior in a square cavity with curvilinear corners and central circular obstacles

Thermal analysis through natural convection and heated obstacles in a different shape of cavity become an emerging concept among the scientific community. In this framework, this study investigates the natural convection phenomena occurring within a square cavity featuring a non-standard curvilinear shape and internally placed circular obstacles. The analysis focuses on the heat and fluid flow behavior in this unique geometrical configuration, exploring the influence of curvilinear boundaries and obstacles on convective heat transfer. The flow is assumed steady, laminar, and incompressible whereas a magnetic field with strength B0 is applied perpendicular to the fluid flow. No slip conditions are applied on each surface. The curvilinear corners and the inner circular obstacle are kept hot and the others including the bottom, left, right, and top walls are considered at cold temperatures. Numerical simulations are conducted to elucidate the complex interactions between the thermal gradients and fluid motion induced by the presence of circular obstacles. Galerkin finite element method is applied. The code validation and comparison with the existing data are being made. It is demonstrated that the local Nusselt number depends upon Rayleigh numbers, obstruction size, and Hartmann numbers. As the obstacles radius increases from 0.1 to 0.3, the temperature distribution in the middle of the cavity increases by almost 400%. This aids engineering in the manipulation of the heat transfer equipment used in this investigation. Around four corners, the local minimum Nusselt number rises by almost 97% as the radius increases from 0.1 to 0.3. These findings offer insightful knowledge about the fluid's dynamic behavior and a nice understanding of the roles played by geometric features, buoyancy-driven convection, and magnetic effects in the overall dynamics of heat transfer in industrial thermal processes. This knowledge aids scientists in designing suitable heat exchangers based on actual conditions.

Salt Stress Tolerance-Promoting Proteins and Metabolites under Plant-Bacteria-Salt Stress Tripartite Interactions

The rapid increase in soil salinization has impacted agricultural output and poses a threat to food security. There is an urgent need to focus on improving soil fertility and agricultural yield, both of which are severely influenced by abiotic variables such as soil salinity and sodicity. Abiotic forces have rendered one-third of the overall land unproductive. Microbes are the primary answer to the majority of agricultural production’s above- and below-ground problems. In stressful conditions, proper communication between plants and beneficial microbes is critical for avoiding plant cell damage. Many chemical substances such as proteins and metabolites synthesized by bacteria and plants mediate communication and stress reduction. Metabolites such as amino acids, fatty acids, carbohydrates, vitamins, and lipids as well as proteins such as aquaporins and antioxidant enzymes play important roles in plant stress tolerance. Plant beneficial bacteria have an important role in stress reduction through protein and metabolite synthesis under salt stress. Proper genomic, proteomic and metabolomics characterization of proteins and metabolites’ roles in salt stress mitigation aids scientists in discovering a profitable avenue for increasing crop output. This review critically examines recent findings on proteins and metabolites produced during plant-bacteria interaction essential for the development of plant salt stress tolerance.

Forward to AIDS 2014: Now is the Time to Unite for the Global HIV/AIDS Epidemic.

As AIDS activists, advocates, researchers, practitioners, scientists, and policy makers from around the world prepare for the forthcoming 20th International AIDS Conference (AIDS 2014) which takes place from 20-25 July in Melbourne, Australia, Gregory Pappas, MD, PhD, former Executive Director of the Washington DC's local Host Committee, International AIDS Society (IAS) organizing committee member, and Director, HIV/AIDS Program in the District of Columbia, Washington, DC, USA, reflects, for the first time, on his experiences hosting the world conference and bringing AIDS conference to United States after 22 years. He shares some of the key challenges and opportunities confronting program planners, policy makers and advocates in the efforts to address the global epidemic.

Deliberating International Science Policy Controversies: Uncertainty and AIDS in South Africa

International science policy controversies involve disputes over cultural differences in the assessment of knowledge claims and competing visions of the policy-making process between different nations. This essay analyzes these dynamics in the recent controversy surrounding AIDS policy in South Africa. It develops the notion of an epistemological filibuster, an appeal to uncertainty in order to delay policy implementation, and shows the key role it played in producing an argumentative stalemate between President Thabo Mbeki and Western orthodox AIDS scientists that threatened millions of HIV-positive South Africans.

The Epistemic Cultures of Science andWikipedia: A Comparison

ABSTRACTI compare the epistemic culture ofWikipediawith the epistemic culture of science, with special attention to the culture of collaborative research in science. The two cultures differ markedly with respect to (1) the knowledge produced, (2) who produces the knowledge, and (3) the processes by which knowledge is produced.Wikipediahas created a community of inquirers that are governed by norms very different from those that govern scientists. Those who contribute toWikipediado not ground their claims on their reputations as knowers, for they stand to lose nothing if and when their contributions are found to be misleading or false. And the immediacy of the medium encourages gossip and jokes. Hence, though we have some reason to believe that an invisible hand aids scientists in realizing their epistemic goals, we cannot ground our confidence in what is reported onWikipediaon the fact that an invisible hand ensures quality. Nor is the information onWikipediaaptly justified in a manner similar to the way testimony can be justified.

Gender differences in attitudes toward AIDS clinical trials among urban HIV-infected individuals from racial and ethnic minority backgrounds

Racial/ethnic minorities and women are under-represented in AIDS clinical trials (ACTs). We examined gender differences in willingness to participate in ACTs among urban HIV-infected individuals (N=286). Sixty percent of participants were male, and most were from racial/ethnic minority backgrounds (55% African-American, 34% Latino/Hispanic, 11% White/other). Knowledge of ACTs was poor. Males and females did not differ substantially in their distrust of AIDS scientists, or in barriers to ACTs. Almost all (87%) were somewhat or very willing to join ACTs. Females were less willing than males to join, including trials testing new medications or new medication combinations. Males and females differed in correlates of willingness to participate in ACTs. Despite long-standing barriers to medical research among minorities and women, willingness to participate was substantial, particularly for men, although the factors that might motivate them to join differed by gender. Women appeared more averse to trials involving new anti-retroviral regimens than men. Gender-specific outreach, behavioural intervention, and social marketing efforts are needed.

Travel Rules Rile Researchers

A controversial Bush Administration decision to cap the number of government researchers allowed to attend meetings outside the country apparently doesn't apply when the United States is the host—even if the meeting is across the ocean ( Science , 24 February, [p. 1086][1]). AIDS scientists are

The end or the beginning of the drive to an HIV-preventive vaccine: a view from over 20 years

Richard Horton has seriously questioned the possibility of developing a successful HIV-preventive vaccine and has appropriately criticised an over optimistic attitude promoted by some individuals in the HIV-vaccine research community. Hortons piece is for the most part on the mark and useful. However there are points that I believe will benefit from clarification. Whereas he rightly points out that some people working on HIV made glib statements for an early vaccine success this position was never that of most leading HIV scientists. Indeed many AIDS scientists regularly acknowledge the possibility of the impossibility of success. Horton implies that the International AIDS Vaccine Initiative (IAVI) once held an optimistic position but most scientists recognised that this was naive and IAVI like most scientists no longer argues that a vaccine is just around the corner. Correctly Horton criticises a vaccine efficacy trial but it is noteworthy that most AIDS scientists were also not pleased that this trial went forward and were keenly aware that it had little or no chance of success. I think we can all agree that continued promotion testing and predictable failure of vaccines that are not evidence-based will continue to foster negative views about HIV-vaccine development thus leading some to the conclusion that vaccine research should be curtailed. There is no doubt that successful development of an HIV-preventive vaccine does present some unusual obstacles. (excerpt)

Antenatal HIV Screening and Treatment in South Africa: Social Norms and Policy Options

South Africa has one of the highest prevalence of HIV and AIDS in the world, with mother-to-child transmission being an important route for spread of the infection. For years, AIDS scientists and activists locally and internationally have been working desperately for the people of South Africa to have access to treatment for HIV and AIDS. Policymakers in South Africa have consistently maintained that HIV infection is not responsible for AIDS, thus creating the biggest obstacle to implementation of appropriate prevention and therapeutic programmes, including antiretroviral therapy for HIV positive persons. Only recently, people within the government and ruling party, defying previous policy, have agreed that antiretroviral drugs should be given to pregnant women with HIV. The social fabric of South African society is markedly different from that of Western countries. In this paper, the author analyses the likely implications of antenatal testing and treatment of pregnant women in South Africa, in light of the socio-economic and cultural status of women in that society.

An editorial for the HIV infected: immune regulation. The implications for treatment of HIV infection and the potential role of T cell suppressor pathways instead of apopstasis, anergy or direct CD4 T cell deletion in AIDS pathogenesis

The AIDS crises makes for an interesting study of the interactions of activists, researchers, caregivers, the press, politicians and other groups in society. In the popular press and elsewhere there has been a growing movement since the inception of the disease to place efforts against AIDS as the highest standard of our benevolence, proficiency and determination when confronting a disease. Because of the potential benefit in understanding the interactions of groups and how research progressed and failed during the AIDS crises, differing perspectives should be recorded on this matter. The person currently in most need of an objective viewpoint on AIDS research, including an outlook on the past, as well as the present and future, is the person who is infected with HIV. While many of the AIDS related bureaucracies, scientists and celebrities have achieved consecration in the fight against HIV, a question arises whether this praise is deserved and really due to their keeping the AIDS patient as the first matter of the heart and mind; or whether they have merely achieved what bureaucracies and celebrity are best at, making society and those they should serve, think that they cannot do with out them. The following editorial chronicles a scandalous intellectual failure of immunologists in the fight against HIV. It delineates potential areas of concern for the HIV infected patient in the present and future, which may be important directions in the fight against HIV, both for treatment to evolve to the ideal and for an economically viable treatment for the Third World.

On the fault-line: The politics of AIDS policy in contemporary South Africa

In a context where the state has had the power to implement major policy initiatives such as the macro-economic Growth Employment and Redistribution (GEAR) strategy why has conflict around AIDS policy persisted as high politics? What explains the apparent inability of the state to exercise effective leadership and deal decisively with AIDS the particular strategies it has adopted in relation to AIDS activists and scientists and the ability of these activists and scientists to apply ongoing pressure and even precipitate a political crisis at the centre of power in the new state? This paper attempts to answer these questions through a closer examination of the various responses to AIDS in South Africa as a distinct set of social relations within the post-apartheid landscape. The particularity of the AIDS world or field is partly explained by the emergence of a fatal disease that has crossed and generated responses that cross many conventional social boundaries involving a wide variety of actors; and partly by the fact that it has spawned both local and global social movements. (excerpt)

Profile. An ambassador of research.

Elizabeth Ngugi, a nurse and social worker with a collaborative AIDS research program based at the University of Nairobi, plays a role that is crucial for many AIDS projects throughout Africa--but one that seldom receives credit in scientific circles. Like an ambassador of research, Ngugi connects ostracized communities that have little education and even less money to an international team of AIDS scientists.

New grid of Arctic bathymetry aids scientists and mapmakers

For over two decades, Sheet 5.17 of the Fifth Edition of the General Bathymetric Chart of the Oceans (GEBCO) [Canadian Hydrographic Service, 1979] has been considered the authoritative portrayal of the sea floor north of 64 N.This sheet was constructed from publicly available bathymetric data sets, which in the late 1970s were rather sparse, consisting almost entirely of underway measurements collected from ice‐breakers, drifting ice islands, and point measurements obtained along snow‐mobile tracks or using air support. Data coverage tended to be fairly good at lower latitudes where ice cover was not a hindrance, but at higher latitudes, where ice was more prevalent, major features such as the Amerasian and Eurasian Basins were not well delineated. This situation posed problems not only for expedition planners but also for scientific investigators, who needed an accurate description of the sea floor to design field experiments and to link their research with processes affecting or affected by the shape of the seabed (for example, sea level change, ocean circulation, sediment transport,seafloor spreading, and Pleistocene glaciation).

AIDS in the public eye: is the epidemic viewed as a crisis?

To determine public opinion about the importance of AIDS as a social and policy issue, we conducted a telephone survey of a nationwide random probability sample of adults in the United States, summer 1991. Thirteen hundred and fifty adults completed the survey. The response rate was 63%. We found that 93% of respondents believe that AIDS is a crisis, and 90% believe that AIDS in the US is out of control. In addition, most people reported believing that the government should spend as much as necessary to solve the AIDS epidemic and that AIDS is a problem for everyone in society, not just those who have the disease. Respondents who had a personal connection to the AIDS epidemic (e.g., knew someone infected with HIV) and those who did not have such a connection equally believe that AIDS is an important social and political issue. In conclusion, we found that AIDS is being accorded great importance by the majority of the US public, regardless of demographic group membership and individual personal connection to the epidemic. However, AIDS scientists must be mindful of potential shifts in public opinion when considering strategies to disseminate research findings.

AIDS Vaccine Trials: Bumpy Road Ahead

AIDS scientists met in February 1991 to discuss international trials of AIDS vaccines because of the urgency in conducting such trials since the US Food and Drug Administration approved 6 vaccines for trails. Major problems discussed were how to insure access to potential AIDS vaccines to developing countries where to conduct future tests of vaccine efficacy and which of the leading institutions should coordinate such an effort. The most difficult issue centered around who assumes the risks and who benefits. Many researchers considered conducting AIDS vaccine trials in developing countries since they have a large population varied in age and gender at high risk of HIV infection. Assuming an HIV vaccine is effective additional questions must be addressed: How can a developing country afford a vaccine at free market prices? If that country does get the vaccine should not other developing countries also get it? Who will pay for it and distribute it? WHO has already contacted ministries of health about AIDS trials. Other organizations e.g. the US Centers for Disease Control and the US National Institutes of Health also already involved in international AIDS vaccine research do not want to be kept out of the Phase III trials. Some recommended that WHO be the international umbrella others suggested that no organization control all the research. Nevertheless the vaccine will be produced in a rich country and if left to the free market it will be too expensive. 1 suggestions is a 2-tiered pricing plan in which rich countries pay higher prices thereby subsidizing the price in poor countries. Another is a patent exchange where the vaccine developers donate the vaccine patent to an international organization and they in turn can get an extension on an existing patent. Another alternative includes removing AIDS vaccines from the private sector altogether.