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1.
PLoS One ; 19(2): e0297439, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38306349

RESUMO

The impacts of the Anthropocene on climate and biodiversity pose societal and ecological problems that may only be solved by ecosystem restoration. Local to regional actions are required, which need to consider the prevailing present and future conditions of a certain landscape extent. Modeling approaches can be of help to support management efforts and to provide advice to policy making. We present stage one of the LaForeT-PLUC-BE model (Landscape Forestry in the Tropics-PCRaster Land Use Change-Biogeographic & Economic model; in short: LPB) and its thematic expansion module RAP (Restoration Areas Potentials). LPB-RAP is a high-resolution pixel-based scenario tool that relies on a range of explicit land use types (LUTs) to describe various forest types and the environment. It simulates and analyzes future landscape configurations under consideration of climate, population and land use change long-term. Simulated Land Use Land Cover Change (LULCC) builds on dynamic, probabilistic modeling incorporating climatic and anthropogenic determinants as well as restriction parameters to depict a sub-national regional smallholder-dominated forest landscape. The model delivers results for contrasting scenario settings by simulating without and with potential Forest and Landscape Restoration (FLR) measures. FLR potentials are depicted by up to five RAP-LUTs. The model builds on user-defined scenario inputs, such as the Shared Socioeconomic Pathways (SSP) and Representative Concentration Pathways (RCP). Model application is here exemplified for the SSP2-RCP4.5 scenario in the time frame 2018-2100 on the hectare scale in annual resolution using Esmeraldas province, Ecuador, as a case study area. The LPB-RAP model is a novel, heuristic Spatial Decision Support System (SDSS) tool for smallholder-dominated forest landscapes, supporting near-time top-down planning measures with long-term bottom-up modeling. Its application should be followed up by FLR on-site investigations and stakeholder participation across all involved scales.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodos , Florestas , Biodiversidade , Agricultura Florestal/métodos
2.
AIDS Behav ; 26(7): 2279-2298, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35034238

RESUMO

The purpose of this scoping review is to establish the state of the art on economic evaluations in the field of HIV/STI prevention in high-income countries with concentrated epidemic settings and to assess what we know about the cost-effectiveness of different measures. We reviewed economic evaluations of HIV/STI prevention measures published in the Web of Science and Cost-Effectiveness Registry databases. We included a total of 157 studies focusing on structural, behavioural, and biomedical interventions, covering a variety of contexts, target populations and approaches. The majority of studies are based on mathematical modelling and demonstrate that the preventive measures under scrutiny are cost-effective. Interventions targeted at high-risk populations yield the most favourable results. The generalisability and transferability of the study results are limited due to the heterogeneity of the populations, settings and methods involved. Furthermore, the results depend heavily on modelling assumptions. Since evidence is unequally distributed, we discuss implications for future research.


RESUMEN: El objetivo de esta revisión de alcance ("scoping review") es exeminar las investigaciones realizadas acerca de las evaluaciones económicas en el campo de la prevención del VIH/ITS en países de altos ingresos con epidemia concentrada y evaluar actuales conocimientos sobre las relaciones costoeficacia de las diferentes medidas. Con este objetivo han sido revi-sadas las evaluaciones económicas de las medidas de prevención del VIH/ITS publicadas en las bases de datos Web of Science y Cost- Effectiveness Registry. Incluidos fueron 157 estudios sobre intervenciones estructurales, conductuales y biomédicas que abarcan una variedad de contextos, poblaciones objetivo y enfoques. La mayoría de los estudios se basan en modelos matemáticos y demuestran que las medidas preventivas analizadas son costo-efectivas. Las intervenciones dirigidas a poblaciones de alto riesgo han mostrado los resultados más favorables. La generalizabilidad y transferibilidad de los hallazgos son limitadas debido a la heterogeneidad de las poblaciones, los escenarios y de los métodos utilizados. Además, los resultados dependen en gran medida de las hipótesis de modelización. Dado que las pruebas están distribuidas de forma desigual, se discuten las implicaciones para una futura investigación.


Assuntos
Epidemias , Infecções por HIV , Infecções Sexualmente Transmissíveis , Análise Custo-Benefício , Países Desenvolvidos , Epidemias/prevenção & controle , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle
3.
BMJ Open ; 10(1): e032459, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31969364

RESUMO

OBJECTIVES: To study the implementation, effects and costs of Break the Chains, a community-based HIV prevention campaign for men who have sex with men (MSM) in Switzerland, from March to May 2015, which aimed to reduce early HIV transmission by promoting the campaign message to adopt short-term risk reduction followed by HIV testing. DESIGN: Non-randomised evaluation and cost analysis. SETTING: Gay venues in 11 of 26 cantons in Switzerland and national online media campaign. PARTICIPANTS: MSM in online surveys (precampaign n=834, postcampaign n=688) or attending HIV testing centres (n=885); campaign managers (n=9); and campaign staff (n=38) or further intermediaries (n=80) in an online survey. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome measure was the proportion of MSM at risk of HIV acquisition or transmission who adhered to the campaign message. Secondary outcomes were postcampaign test uptake, knowledge about HIV primary infection and sense of belonging to the gay community. RESULTS: Campaign staff estimated that they contacted 17 145 MSM in 11 cantons. Among 688 respondents to the postcampaign survey, 311 (45.2%) were categorised as MSM at risk. Of 402/688 (58.5%) MSM who had heard about Break the Chains 2015, MSM categorised as being at risk were less likely to report adherence to the campaign message than MSM not at risk (adjusted OR 0.24; 95% CI 0.14 to 0.42). Twenty per cent of MSM with a defined risk of HIV acquisition or transmission who adopted risk reduction declared having done so because of the campaign. Costs for one MSM at risk to adhere to the campaign message were estimated at USD purchasing power parity 36-55. The number of HIV tests in the month after the campaign was twice the monthly average. CONCLUSION: Break the Chains increased HIV testing, implying that community-based campaigns are useful HIV prevention strategies for MSM. Additional interventions are needed to reach MSM at the highest risk of infection more effectively.


Assuntos
Infecções por HIV/prevenção & controle , Promoção da Saúde/economia , Homossexualidade Masculina/estatística & dados numéricos , Programas de Rastreamento/economia , Adulto , Custos e Análise de Custo , Infecções por HIV/economia , Infecções por HIV/epidemiologia , Humanos , Incidência , Masculino , Programas de Rastreamento/métodos , Assunção de Riscos , Minorias Sexuais e de Gênero , Suíça/epidemiologia
4.
J Phys Chem B ; 121(6): 1248-1257, 2017 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-28106397

RESUMO

Detergents are commonly applied in lipase assays to solubilize sparingly soluble model substrates. However, detergents affect lipases as well as substrates in multiple ways. The effect of detergents on lipase activity is commonly attributed to conformational changes in the lid region. This study deals with the effect of the nonionic detergent, poly(ethylene glycol) dodecyl ether, on a lipase that does not contain a lid sequence, lipase A from Bacillus subtilis (BSLA). We show that BSLA activity depends strongly on the detergent concentration and the dependency profile changes with pH. The interaction of BSLA with detergent monomers and micelles is studied using fluorescence correlation spectroscopy, time-resolved anisotropy decay, and temperature-induced unfolding. Detergent-dependent hydrolysis kinetics of two different substrates at two pH values are fitted with a microkinetic model. This analysis shows that the mechanism of interfacial lipase catalysis is strongly affected by the detergent. It reveals an activation mechanism by monomeric detergent that does not result from structural changes of the lipase. Instead, we propose that interfacial diffusion of the lipase is enhanced by detergent binding.


Assuntos
Detergentes/farmacologia , Inibidores Enzimáticos/farmacologia , Éteres/farmacologia , Lipase/antagonistas & inibidores , Polietilenoglicóis/farmacologia , Bacillus subtilis/enzimologia , Detergentes/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/química , Éteres/química , Cinética , Lipase/metabolismo , Estrutura Molecular , Polietilenoglicóis/química , Relação Estrutura-Atividade
5.
Eur Biophys J ; 44(8): 655-65, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26224303

RESUMO

Because of their vast diversity of substrate specificity and reaction conditions, lipases are versatile materials for biocatalysis. Lipase A from Bacillus subtilis (BSLA) is the smallest lipase yet discovered. It has the typical α/ß hydrolase fold but lacks a lid covering the substrate cleft. In this study, the pH-dependence of the activity, stability, structure, and dynamics of BSLA was investigated by fluorescence spectroscopy. By use of a fluorogenic substrate it was revealed that the optimum pH for BSLA activity is 8.5 whereas thermodynamic and kinetic stability are maximum at pH 10. The origin of this behavior was clarified by investigation of ANS (8-anilino-1-naphthalenesulfonic acid) binding and fluorescence quenching of the two single tryptophan mutants W31F and W42F. Variations in segmental dynamics were investigated by use of time-resolved fluorescence anisotropy. This analysis showed that the activity maximum is governed by high surface hydrophobicity and high segmental mobility of surface loops whereas the stability optimum is a result of low segmental mobility and surface hydrophobicity.


Assuntos
Proteínas de Bactérias/química , Lipase/química , Naftalenossulfonato de Anilina/química , Bacillus subtilis/enzimologia , Proteínas de Bactérias/metabolismo , Domínio Catalítico , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Lipase/metabolismo , Simulação de Dinâmica Molecular , Ligação Proteica , Termodinâmica
6.
J Int AIDS Soc ; 14 Suppl 2: S7, 2011 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-21968292

RESUMO

BACKGROUND: Research policy in the field of HIV has changed substantially in recent decades in Switzerland. Until 2004, social science research on HIV/AIDS was funded by specialized funding agencies. After 2004, funding of such research was "normalized" and integrated into the Swiss National Science Foundation as the main funding agency for scientific research in Switzerland. This paper offers a longitudinal analysis of the relationship between the changing nature of funding structures on the one hand and the production and communication of policy-relevant scientific knowledge in the field of HIV on the other hand. METHODS: The analysis relies on an inventory of all social sciences research projects on HIV in Switzerland that were funded between 1987 and 2010, including topics covered and disciplines involved, as well as financial data. In addition, in-depth interviews were conducted with 18 stakeholders. RESULTS: The analysis highlights that the pre-2004 funding policy ensured good coverage of important social science research themes. Specific incentives and explicit promotion of social science research related to HIV gave rise to a multidisciplinary, integrative and health-oriented approach. The abolition of a specific funding policy in 2004 was paralleled by a drastic reduction in the number of social science research projects submitted for funding, and a decline of public money dedicated to such research. Although the public administration in charge of HIV policy still acknowledges the relevance of findings from social sciences for the development of prevention, treatment and care, HIV-related social science research does not flourish under current funding conditions. CONCLUSIONS: The Swiss experience sheds light on the difficulties of sustaining social science research and multidisciplinary approaches related to HIV without specialized funding agencies. Future funding policy might not necessarily require specialized agencies, but should better take into account research dynamics and motivations in the field of social sciences.


Assuntos
Infecções por HIV/economia , Pesquisa/economia , Ciências Sociais/economia , Síndrome da Imunodeficiência Adquirida/economia , Administração Financeira , Humanos , Política Pública , Suíça
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