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1.
Opt Express ; 27(3): 3324-3336, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30732355

RESUMO

We report optical constants of e-beam evaporated yttrium oxide Y2O3 thin films as determined from angle-dependent reflectance measurements at wavelengths from 5 to 50 nm. Samples were measured using synchrotron radiation at the Advanced Light Source. The experimental reflectance data were fit to obtain values for the index of refraction and thin film roughness. We compare our computed constants with those of previous researchers and those computed using the independent atom approximation from the CXRO website. We found that the index of refraction near 36 nm is much lower than previous data from Tomiki as reported by Palik. The real part of the optical constants is about 10% to 15% below CXRO values for wavelengths between 17 nm and 30 nm. Films were also characterized chemically, structurally, and optically by ellipsometry and atomic force microscopy.

2.
Acta Trop ; 188: 108-117, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30118701

RESUMO

Japanese encephalitis virus (JEV) is a substantial cause of viral encephalitis, morbidity, and mortality in South-East Asia and the Western Pacific. World Health Organization recognized Japanese Encephalitis (JE) as a public health priority in demands to initiate active vaccination programs. Recently, the geographic distribution of JEV has apparently expanded into other areas in the Pacific islands and northern Australia; however, major gaps exist in knowledge in regard to its current distribution. Here, we mapped the potential distribution of mosquito vectors of JEV (Culex tritaeniorhynchus, Cx. pseudovishnui, Cx. vishnui, Cx. fuscocephala, Cx. gelidus), and reservoirs (Egretta garzetta, E. intermedia, Nycticorax nycticorax) based on ecological niche modeling approach. Ecological niche models predicted all species to occur across Central, South and South East Asia; however, Cx. tritaeniorhynchus, E. garzetta, E. intermedia, and N. nycticorax had broader potential distributions extending west to parts of the Arabian Peninsula. All predictions were robust and significantly better than random (P < 0.001). We also tested the JEV prediction based on 4335 additional independent human case records collected by the Chinese Information System for Disease Control and Prevention (CISDCP); 4075 cases were successfully predicted by the model (P < 0.001). Finally, we tested the ecological niche similarity among JEV, vector, and reservoir species and could not reject any of the null hypotheses of niche similarity in all combination pairs.


Assuntos
Reservatórios de Doenças , Encefalite Japonesa/transmissão , Mosquitos Vetores , Animais , Culex/virologia , Ecologia , Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa/etiologia , Humanos
3.
Integr Blood Press Control ; 10: 25-32, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29075138

RESUMO

Elevated blood pressure (BP) and prehypertension increase the risk of cardiovascular diseases, a national health concern. This article presents a quality improvement project implemented within a primary care setting that aimed at lowering cardiovascular risk by improving the identification, treatment, and follow-up of patients with elevated BP. This project was designed and implemented to address the identified deficiencies contributing to poor identification and follow-up of patients with elevated BP. The intervention was multi-pronged and comprised a staff educational program, introduction of a new method for measuring BP using the BpTRU™ device, and patient educational intervention. A significant improvement in staff BP knowledge scores was achieved following the intervention (p<0.05). Patient participants also exhibited a significant improvement in post-intervention BP measurements (p<0.05). This project showed that the implementation of a quality improvement project in a primary care setting can lead to significant improvements in staff BP knowledge and patient BP readings. However, future research in this area is required to determine whether particular lifestyle changes are directly associated with the reduction in BP.

4.
Sci Rep ; 7(1): 3813, 2017 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-28630444

RESUMO

The arrival and rapid spread of the mosquito-borne viral disease Chikungunya across the Americas is one of the most significant public health developments of recent years, preceding and mirroring the subsequent spread of Zika. Globalization in trade and travel can lead to the importation of these viruses, but climatic conditions strongly affect the efficiency of transmission in local settings. In order to direct preparedness for future outbreaks, it is necessary to anticipate global regions that could become suitable for Chikungunya transmission. Here, we present global correlative niche models for autochthonous Chikungunya transmission. These models were used as the basis for projections under the representative concentration pathway (RCP) 4.5 and 8.5 climate change scenarios. In a further step, hazard maps, which account for population densities, were produced. The baseline models successfully delineate current areas of active Chikungunya transmission. Projections under the RCP 4.5 and 8.5 scenarios suggest the likelihood of expansion of transmission-suitable areas in many parts of the world, including China, sub-Saharan Africa, South America, the United States and continental Europe. The models presented here can be used to inform public health preparedness planning in a highly interconnected world.


Assuntos
Febre de Chikungunya/epidemiologia , Febre de Chikungunya/transmissão , Mudança Climática , Bases de Dados Factuais , Modelos Biológicos , Feminino , Humanos , Masculino
5.
Mem Inst Oswaldo Cruz ; 111(9): 559-60, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27653360

RESUMO

The Americas are presently experiencing the most serious known outbreak of Zika virus (ZIKV). Here, we present a novel set of analyses using environmental characteristics, vector mosquito distributions, and socioeconomic risk factors to develop the first map to detail global ZIKV transmission risk in multiple dimensions based on ecological niche models. Our model predictions were tested against independent evaluation data sets, and all models had predictive ability significantly better than random expectations. The study addresses urgent knowledge gaps regarding (1) the potential geographic scope of the current ZIKV epidemic, (2) the global potential for spread of ZIKV, and (3) drivers of ZIKV transmission. Our analysis of potential drivers of ZIKV distributions globally identified areas vulnerable in terms of some drivers, but not for others. The results of these analyses can guide regional education and preparedness efforts, such that medical personnel will be better prepared for diagnosis of potential ZIKV cases as they appear.


Assuntos
Aedes/virologia , Saúde Global , Insetos Vetores/virologia , Infecção por Zika virus/epidemiologia , Zika virus , Animais , Surtos de Doenças , Humanos , Modelos Biológicos , Fatores de Risco , Fatores Socioeconômicos , Infecção por Zika virus/transmissão
6.
Mem. Inst. Oswaldo Cruz ; 111(9): 559-560, Sept. 2016. graf
Artigo em Inglês | LILACS | ID: lil-794729

RESUMO

The Americas are presently experiencing the most serious known outbreak of Zika virus (ZIKV). Here, we present a novel set of analyses using environmental characteristics, vector mosquito distributions, and socioeconomic risk factors to develop the first map to detail global ZIKV transmission risk in multiple dimensions based on ecological niche models. Our model predictions were tested against independent evaluation data sets, and all models had predictive ability significantly better than random expectations. The study addresses urgent knowledge gaps regarding (1) the potential geographic scope of the current ZIKV epidemic, (2) the global potential for spread of ZIKV, and (3) drivers of ZIKV transmission. Our analysis of potential drivers of ZIKV distributions globally identified areas vulnerable in terms of some drivers, but not for others. The results of these analyses can guide regional education and preparedness efforts, such that medical personnel will be better prepared for diagnosis of potential ZIKV cases as they appear.


Assuntos
Humanos , Animais , Aedes/virologia , Saúde Global , Insetos Vetores/virologia , Zika virus , Infecção por Zika virus/epidemiologia , Surtos de Doenças , Modelos Biológicos , Fatores de Risco , Fatores Socioeconômicos , Infecção por Zika virus/transmissão
7.
Int J Health Geogr ; 12: 51, 2013 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-24219507

RESUMO

BACKGROUND: Chikungunya was, from the European perspective, considered to be a travel-related tropical mosquito-borne disease prior to the first European outbreak in Northern Italy in 2007. This was followed by cases of autochthonous transmission reported in South-eastern France in 2010. Both events occurred after the introduction, establishment and expansion of the Chikungunya-competent and highly invasive disease vector Aedes albopictus (Asian tiger mosquito) in Europe. In order to assess whether these outbreaks are indicative of the beginning of a trend or one-off events, there is a need to further examine the factors driving the potential transmission of Chikungunya in Europe. The climatic suitability, both now and in the future, is an essential starting point for such an analysis. METHODS: The climatic suitability for Chikungunya outbreaks was determined by using bioclimatic factors that influence, both vector and, pathogen. Climatic suitability for the European distribution of the vector Aedes albopictus was based upon previous correlative environmental niche models. Climatic risk classes were derived by combining climatic suitability for the vector with known temperature requirements for pathogen transmission, obtained from outbreak regions. In addition, the longest potential intra-annual season for Chikungunya transmission was estimated for regions with expected vector occurrences.In order to analyse spatio-temporal trends for risk exposure and season of transmission in Europe, climate change impacts are projected for three time-frames (2011-2040, 2041-2070 and 2071-2100) and two climate scenarios (A1B and B1) from the Intergovernmental Panel on Climate Change (IPCC). These climatic projections are based on regional climate model COSMO-CLM, which builds on the global model ECHAM5. RESULTS: European areas with current and future climatic suitability of Chikungunya transmission are identified. An increase in risk is projected for Western Europe (e.g. France and Benelux-States) in the first half of the 21st century and from mid-century onwards for central parts of Europe (e.g. Germany). Interestingly, the southernmost parts of Europe do not generally provide suitable conditions in these projections. Nevertheless, many Mediterranean regions will persist to be climatically suitable for transmission. Overall, the highest risk of transmission by the end of the 21st century was projected for France, Northern Italy and the Pannonian Basin (East-Central Europe). This general tendency is depicted in both, the A1B and B1 climate change scenarios. CONCLUSION: In order to guide preparedness for further outbreaks, it is crucial to anticipate risk as to identify areas where specific public health measures, such as surveillance and vector control, can be implemented. However, public health practitioners need to be aware that climate is only one factor driving the transmission of vector-borne disease.


Assuntos
Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/transmissão , Mudança Climática , Mapeamento Geográfico , Insetos Vetores , Estações do Ano , Aedes , Animais , Febre de Chikungunya , Europa (Continente)/epidemiologia , Humanos , Insetos Vetores/fisiologia
8.
PLoS Negl Trop Dis ; 5(11): e1407, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22140590

RESUMO

BACKGROUND: In the Old World, sandfly species of the genus Phlebotomus are known vectors of Leishmania, Bartonella and several viruses. Recent sandfly catches and autochthonous cases of leishmaniasis hint on spreading tendencies of the vectors towards Central Europe. However, studies addressing potential future distribution of sandflies in the light of a changing European climate are missing. METHODOLOGY: Here, we modelled bioclimatic envelopes using MaxEnt for five species with proven or assumed vector competence for Leishmania infantum, which are either predominantly located in (south-) western (Phlebotomus ariasi, P. mascittii and P. perniciosus) or south-eastern Europe (P. neglectus and P. perfiliewi). The determined bioclimatic envelopes were transferred to two climate change scenarios (A1B and B1) for Central Europe (Austria, Germany and Switzerland) using data of the regional climate model COSMO-CLM. We detected the most likely way of natural dispersal ("least-cost path") for each species and hence determined the accessibility of potential future climatically suitable habitats by integrating landscape features, projected changes in climatic suitability and wind speed. RESULTS AND RELEVANCE: Results indicate that the Central European climate will become increasingly suitable especially for those vector species with a current south-western focus of distribution. In general, the highest suitability of Central Europe is projected for all species in the second half of the 21st century, except for P. perfiliewi. Nevertheless, we show that sandflies will hardly be able to occupy their climatically suitable habitats entirely, due to their limited natural dispersal ability. A northward spread of species with south-eastern focus of distribution may be constrained but not completely avoided by the Alps. Our results can be used to install specific monitoring systems to the projected risk zones of potential sandfly establishment. This is urgently needed for adaptation and coping strategies against the emerging spread of sandfly-borne diseases.


Assuntos
Mudança Climática , Vetores de Doenças , Phlebotomus/crescimento & desenvolvimento , Animais , Áustria , Simulação por Computador , Alemanha , Suíça
9.
Geospat Health ; 5(1): 59-69, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21080321

RESUMO

Climate change is expected to manifest in the shift of organisms to regions where they were not present in the past, potentially entailing previously unseen biological risks. However, studies evaluating these future trends are scarce. Here, an important group of vectors (sandflies) and the pathogen transmitted (Leishmania infantum complex) causing the infectious disease visceral leishmaniasis is investigated, focussing on potential establishment in Germany during the 21st century. As the most important habitat factor, temperature requirements of pathogen and vector were derived from the literature and compared with recent climate records - provided by worldclim - and climate change scenarios. Climate data from the Regional Climate Model REMO were obtained and averaged over the time periods 2011- 2040, 2041-2070 and 2071-2100. Projected temperature changes (based on the A1B and A2 scenarios) were correlated with the constraints of vector and pathogen. Simulated potentially suitable habitat areas for vector and pathogen were merged to generate a temperature-derived risk map of visceral leishmaniasis. Temperature conditions seem to become suitable for the vector across large swaths of Germany. Nevertheless, temperature constraints for the pathogen may defer the establishment of the parasitic disease, particularly during the first half of the 21st century. Long-lasting epidemics of visceral leishmaniasis are therefore not expected in Germany during the next few decades, although during extremely warm years an increase in autochthonous cases of leishmaniasis may occur. The southwest (Upper Rhine Valley) and west (Cologne Bight) of Germany are identified as risk areas. The time of potential establishment and corresponding rise in biological risk varies between scenarios, due to differences in the predicted rate of temperature increase.


Assuntos
Aquecimento Global/estatística & dados numéricos , Leishmaniose Visceral/epidemiologia , Phlebotomus/parasitologia , Temperatura , Animais , Mudança Climática/estatística & dados numéricos , Ecossistema , Geografia , Alemanha/epidemiologia , Humanos , Leishmaniose Visceral/transmissão , Psychodidae/parasitologia , Fatores de Risco
10.
Clin Infect Dis ; 38 Suppl 3: S190-7, 2004 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15095189

RESUMO

In 2000, we surveyed microbiologists in 388 clinical laboratories, which tested an estimated 339,000 stool specimens in 1999, about laboratory methods and policies for the routine testing of stool specimens for Salmonella, Shigella, Campylobacter, and Vibrio species, Yersinia entercolitica, and Escherichia coli O157:H7. The results were compared with those of similar surveys conducted in 1995 and 1997. Although these laboratories reported routinely testing for Salmonella, Shigella, and Campylobacter species, only 57% routinely tested for E. coli O157:H7, 50% for Y. entercolitica, and 50% for Vibrio species. The mean proportions of stool specimens that yielded these pathogens were as follows: Campylobacter, 1.3% of specimens; Salmonella, 0.9%; Shigella, 0.4%; and E. coli O157:H7, 0.3%. The proportion of laboratories that routinely tested for E. coli O157:H7 increased from 59% in 1995 to 68% in 2000; however, the proportion of stool specimens tested decreased from 53% to 46%. E. coli O157:H7 should be routinely sought in stool specimens submitted for microbiologic culture.


Assuntos
Técnicas de Laboratório Clínico , Infecções por Escherichia coli/epidemiologia , Escherichia coli O157 , Fezes/microbiologia , Campylobacter , Infecções por Escherichia coli/microbiologia , Humanos , Salmonella , Shigella , Estados Unidos/epidemiologia , Vibrio , Yersinia
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