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1.
Waste Manag Res ; 40(7): 870-881, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34823396

RESUMEN

Forecasting the scale of e-waste recycling is the basis for the government to formulate the development plan of circular economy and relevant subsidy policies and enterprises to evaluate resource recovery and optimise production capacity. In this article, the CH-X12 /STL-X framework for e-waste recycling scale prediction is proposed based on the idea of 'decomposition-integration', considering that the seasonal data characteristics of quarterly e-waste recycling scale data may lead to large forecasting errors and inconsistent forecasting results of a traditional single model. First, the seasonal data characteristics of the time series of e-waste recovery scale are identified based on Canova-Hansen (CH) test, and then the time series suitable for seasonal decomposition is extracted with X12 or seasonal-trend decomposition procedure based on loess (STL) model for seasonal components. Then, the Holt-Winters model was used to predict the seasonal component, and the support vector regression (SVR) model was used to predict the other components. Finally, the linear sum of the prediction results of each component is used to obtain the final prediction result. The empirical results show that the proposed CH-X12/STL-X forecasting framework can better meet the modelling requirements for time-series forecasting driven by different seasonal data characteristics and has better and more stable forecasting performance than traditional single models (Holt-Winters model, seasonal autoregressive integrated moving average model and SVR model).


Asunto(s)
Residuos Electrónicos , Predicción , Reciclaje , Estaciones del Año , Factores de Tiempo
2.
Commun Biol ; 4(1): 1166, 2021 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-34620991

RESUMEN

Hyperdiverse tropical rainforests, such as the aseasonal forests in Southeast Asia, are supported by high annual rainfall. Its canopy is dominated by the species-rich tree family of Dipterocarpaceae (Asian dipterocarps), which has both ecological (e.g., supports flora and fauna) and economical (e.g., timber production) importance. Recent ecological studies suggested that rare irregular drought events may be an environmental stress and signal for the tropical trees. We assembled the genome of a widespread but near threatened dipterocarp, Shorea leprosula, and analyzed the transcriptome sequences of ten dipterocarp species representing seven genera. Comparative genomic and molecular dating analyses suggested a whole-genome duplication close to the Cretaceous-Paleogene extinction event followed by the diversification of major dipterocarp lineages (i.e. Dipterocarpoideae). Interestingly, the retained duplicated genes were enriched for genes upregulated by no-irrigation treatment. These findings provide molecular support for the relevance of drought for tropical trees despite the lack of an annual dry season.


Asunto(s)
Dipterocarpaceae/genética , Sequías , Duplicación de Gen , Genoma de Planta , Bosque Lluvioso , Malasia , Estaciones del Año
3.
Am J Bot ; 107(11): 1491-1503, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33190268

RESUMEN

PREMISE: Leaf phenology is an essential developmental process in trees and an important component in understanding climate change. However, little is known about the regulation of leaf phenology in tropical trees. METHODS: To understand the regulation by temperature of leaf phenology in tropical trees, we performed daily observations of leaf production under rainfall-independent conditions using saplings of Shorea leprosula and Neobalanocarpus heimii, both species of Dipterocarpaceae, a dominant tree family of Southeast Asia. We analyzed the time-series data obtained using empirical dynamic modeling (EDM) and conducted growth chamber experiments. RESULTS: Leaf production by dipterocarps fluctuated in the absence of fluctuation in rainfall, and the peaks of leaf production were more frequent than those of day length, suggesting that leaf production cannot be fully explained by these environmental factors, although they have been proposed as regulators of leaf phenology in dipterocarps. Instead, EDM suggested a causal relationship between temperature and leaf production in dipterocarps. Leaf production by N. heimii saplings in chambers significantly increased when temperature was increased after long-term low-temperature treatment. This increase in leaf production was observed even when only nighttime temperature was elevated, suggesting that the effect of temperature on development is not mediated by photosynthesis. CONCLUSIONS: Because seasonal variation in temperature in the tropics is small, effects on leaf phenology have been overlooked. However, our results suggest that temperature is a regulator of leaf phenology in dipterocarps. This information will contribute to better understanding of the effects of climate change in the tropics.


Asunto(s)
Dipterocarpaceae , Asia Sudoriental , Hojas de la Planta , Estaciones del Año , Temperatura , Árboles
4.
Indian J Dermatol Venereol Leprol ; 85(5): 462-465, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30757998

RESUMEN

BACKGROUND: Psoralen with ultraviolet A is an effective photochemotherapeutic modality. A subtype of this, PUVAsol, uses sunlight as the natural source of ultraviolet A. The amount of sunlight received and the consequent ultraviolet A exposure vary according to the month in the year, time of the day and geographical location of a place. AIM: The aim of this study is to determine irradiance of ultraviolet A in ambient sunlight and optimum exposure time for PUVAsol. MATERIALS AND METHODS: This was an observational study carried out at Postgraduate Institute of Medical Education and Research, Chandigarh (30.7333°N, 76.7794°E), India using a photometer. Ultraviolet A irradiance was recorded at a fixed place at 10 AM, once weekly for a period of 12 months. RESULTS: The irradiance of peak ultraviolet A was found to be 3.1 mW/cm2 in June 2016 while irradiance of 0.64 mW/cm2 was recorded in January 2017. The exposure time needed for therapeutic dose of 2 J/cm2 was 11 min 6 s in June 2016 while exposure time for achieving therapeutic dose of 2 J/cm2 was 52 min 5 s in January 2017. The duration of exposure was found to be significantly longer in the winter months. LIMITATION: The limitation of the study is not determining ultraviolet B radiation and infrared exposure. Other limitation of this study is that the irradiance was measured only at 10 am. This data cannot be used to determine irradiance at different time points in the day as the patient may expose himself/herself to sunlight anytime depending on his/her convenience. CONCLUSIONS: The study demonstrates the mean exposure time required for a given therapeutic dose of ultraviolet A in different months. The wide variation in ultraviolet A irradiance in natural sunlight over the year in different months also suggests that exposure times for PUVAsol should be based on the season and geographical location at the site of therapy and not based on uniform guidelines.


Asunto(s)
Ficusina/administración & dosificación , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/administración & dosificación , Estaciones del Año , Rayos Ultravioleta , Humanos , India/epidemiología , Luz Solar , Factores de Tiempo
5.
An. bras. dermatol ; 93(5): 755-758, Sept.-Oct. 2018. tab
Artículo en Inglés | LILACS | ID: biblio-1038279

RESUMEN

Abstract: There is little data in the literature concerning dermatologic admissions. Several diseases are seasonal in incidence and clinical worsening. We performed a survey of hospitalizations in the dermatology ward of a public hospital (April/2007 to May/2017). There were 1790 hospitalizations, whose main diagnoses were infectious dermatoses, neoplasias, psoriasis, bullous diseases and cutaneous ulcers. In winter, there were fewer hospitalizations for bacterial infections and urticaria, but more for leprosy. In summer, there were fewer hospitalizations for systemic and subcutaneous mycoses, but more for zoodermatoses and erythema multiforme. In the fall, more patients were admitted with mycoses. Spring favored urticaria and angioedema, but less cases of erythema multiforme and diabetic foot.


Asunto(s)
Humanos , Masculino , Femenino , Estaciones del Año , Enfermedades de la Piel/epidemiología , Hospitalización/estadística & datos numéricos , Admisión del Paciente/estadística & datos numéricos , Enfermedades de la Piel/diagnóstico , Brasil/epidemiología , Incidencia , Enfermedades Cutáneas Bacterianas/epidemiología , Dermatología/estadística & datos numéricos , Tiempo de Internación
6.
An Bras Dermatol ; 93(5): 755-758, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30156635

RESUMEN

There is little data in the literature concerning dermatologic admissions. Several diseases are seasonal in incidence and clinical worsening. We performed a survey of hospitalizations in the dermatology ward of a public hospital (April/2007 to May/2017). There were 1790 hospitalizations, whose main diagnoses were infectious dermatoses, neoplasias, psoriasis, bullous diseases and cutaneous ulcers. In winter, there were fewer hospitalizations for bacterial infections and urticaria, but more for leprosy. In summer, there were fewer hospitalizations for systemic and subcutaneous mycoses, but more for zoodermatoses and erythema multiforme. In the fall, more patients were admitted with mycoses. Spring favored urticaria and angioedema, but less cases of erythema multiforme and diabetic foot.


Asunto(s)
Hospitalización/estadística & datos numéricos , Estaciones del Año , Enfermedades de la Piel/epidemiología , Brasil/epidemiología , Dermatología/estadística & datos numéricos , Femenino , Humanos , Incidencia , Tiempo de Internación , Masculino , Admisión del Paciente/estadística & datos numéricos , Enfermedades de la Piel/diagnóstico , Enfermedades Cutáneas Bacterianas/epidemiología
7.
Ecotoxicol Environ Saf ; 162: 77-84, 2018 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-29990742

RESUMEN

Crop protection agents are widely used in modern agriculture and exert direct effects on non-target microorganisms such as yeasts. Yeasts abundantly colonize wheat grain and affect its chemical composition. They can also limit pathogen growth. This study evaluated the sensitivity of yeast communities colonizing winter wheat kernels to benzimidazole, strobilurin, triazole and morpholine fungicides, trinexapac-ethyl, a commercial mixture of o-nitrophenol+p-nitrophenol+5-nitroguaiacol, and chitosan applied during the growing season of winter wheat and in vitro in a diffusion test. A molecular identification analysis of yeasts isolated from winter wheat kernels was performed, and nucleotide polymorphisms in the CYTb gene (G143A) conferring resistance to strobilurin fungicides in yeast cells were identified. The size of yeast communities increased during grain storage, and the total counts of endophytic yeasts were significantly (85%) reduced following intensive fungicide treatment (fenpropimorph, a commercial mixture of pyraclostrobin, epoxiconazole and thiophanate-methyl). This study demonstrated that agrochemical residues in wheat grain can drive selection of yeast communities for reduced sensitivity to xenobiotics. A mutation in the CYTb gene (G143A) was observed in all analyzed isolates of the following azoxystrobin-resistant species: Aureobasidium pullulans, Debaryomyces hansenii, Candida albicans and C. sake. Agrochemicals tested in vitro were divided into four classes of toxicity to yeasts: (1) tebuconazole and a commercial mixture of flusilazole and carbendazim - most toxic to yeasts; (2) fenpropimorph and a commercial mixture of pyraclostrobin and epoxyconazole; (3) propiconazole, chitosan, thiophanate-methyl and a commercial mixture of o-nitrophenol, p-nitrophenol and 5-nitroguaiacol; (4) trinexapac-ethyl and azoxystrobin - least toxic to yeasts. It was found that agrochemicals can have an adverse effect on yeast abundance and the composition of yeast communities, mostly due to differences in fungicide resistance between yeast species, including the clinically significant C. albicans.


Asunto(s)
Agroquímicos/farmacología , Farmacorresistencia Fúngica/genética , Fungicidas Industriales/farmacología , Triticum/microbiología , Levaduras/efectos de los fármacos , Levaduras/genética , Agaricales/efectos de los fármacos , Agaricales/genética , Ascomicetos/efectos de los fármacos , Ascomicetos/genética , Bencimidazoles/farmacología , Candida albicans/efectos de los fármacos , Candida albicans/genética , Carbamatos/farmacología , Compuestos Epoxi/farmacología , Pruebas de Sensibilidad Microbiana , Residuos de Plaguicidas/análisis , Enfermedades de las Plantas/microbiología , Pirimidinas/farmacología , Estaciones del Año , Silanos/farmacología , Estrobilurinas/farmacología , Triazoles/farmacología , Xenobióticos/farmacología , Levaduras/clasificación
8.
Braz. j. biol ; 76(4): 818-823, Oct.-Dec. 2016. tab, graf
Artículo en Inglés | LILACS | ID: biblio-828094

RESUMEN

Abstract The goal of this study was to identify which bird species consume Solanum granuloso-leprosum fruits and disperse its seeds. 60 hours of focal observations were carried out between April and May 2006 on the edge of a deciduous forest fragment in the Uruguay River region, Rio Grande do Sul state, Brazil. Ten species were observed in total removing 443 fruits. Saltator similis removed 61.8% of the fruits, followed by Tangara sayaca (17.1%), Pipraeidea bonariensis (11.7%), and T. preciosa (6.8%), while the remaining six species accounted for only 2.5% of the fruits removed. Most fruit removal occurred early in the day or mid-afternoon. The most common feeding behaviors were picking (60.7%), followed by stalling (23%) and hovering (16%). Birds flew more than 10 m from the fruit plant in 62% of the removal events. All bird species observed here may be considered potential dispersers of S. granuloso-leprosum, as they moved the seeds away from the mother plant where strong competition and predation are likely to occur. Results also suggest that S. granuloso-leprosum may be useful in ecological restoration programs.


Resumo O objetivo deste estudo foi identificar quais as espécies de aves consomem frutos de Solanum granuloso-leposum e dispersam suas sementes. Para tanto, 60 horas de observações focais foram realizadas entre abril e maio de 2006 na borda de um fragmento de floresta decídua na região do rio Uruguai, Rio Grande do Sul, Brasil. Dez espécies foram observadas removendo 443 frutos. Saltator similis removeu 61,8% dos frutos, seguido de Tangara sayaca (17,1%), Pipraeidea bonariensis (11,7%), e T. preciosa (6,8%), enquanto as restantes seis espécies representaram apenas 2,5% dos frutos removidos. A maioria das remoções dos frutos ocorreram no início do dia ou meio da tarde. Os comportamentos alimentares mais comuns foram picking (60,7%), seguido por stalling (23%) e hovering (16%). As aves voaram mais de 10 m da planta de onde removeram frutos em 62% dos eventos de remoção. Todas as espécies de aves observadas aqui podem ser consideradas potenciais dispersores de S. granuloso-leprosum, moveram sementes para longe da planta-mãe, onde a concorrência e a predação são mais susceptíveis de ocorrer. Os resultados também sugerem que S. granuloso-leprosum pode ser útil em programas de restauração ecológica.


Asunto(s)
Animales , Semillas , Aves/fisiología , Solanum/fisiología , Dispersión de Semillas/fisiología , Herbivoria/fisiología , Estaciones del Año , Brasil , Bosques , Frutas
9.
Braz J Biol ; 76(4): 818-823, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27191463

RESUMEN

The goal of this study was to identify which bird species consume Solanum granuloso-leprosum fruits and disperse its seeds. 60 hours of focal observations were carried out between April and May 2006 on the edge of a deciduous forest fragment in the Uruguay River region, Rio Grande do Sul state, Brazil. Ten species were observed in total removing 443 fruits. Saltator similis removed 61.8% of the fruits, followed by Tangara sayaca (17.1%), Pipraeidea bonariensis (11.7%), and T. preciosa (6.8%), while the remaining six species accounted for only 2.5% of the fruits removed. Most fruit removal occurred early in the day or mid-afternoon. The most common feeding behaviors were picking (60.7%), followed by stalling (23%) and hovering (16%). Birds flew more than 10 m from the fruit plant in 62% of the removal events. All bird species observed here may be considered potential dispersers of S. granuloso-leprosum, as they moved the seeds away from the mother plant where strong competition and predation are likely to occur. Results also suggest that S. granuloso-leprosum may be useful in ecological restoration programs.


Asunto(s)
Aves/fisiología , Herbivoria/fisiología , Dispersión de Semillas/fisiología , Semillas , Solanum/fisiología , Animales , Brasil , Bosques , Frutas , Estaciones del Año
10.
PLoS Negl Trop Dis ; 9(7): e0003941, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26196901

RESUMEN

BACKGROUND: Buruli ulcer, the third mycobacterial disease after tuberculosis and leprosy, is caused by the environmental mycobacterium M. ulcerans. There is at present no clear understanding of the exact mode(s) of transmission of M. ulcerans. Populations affected by Buruli ulcer are those living close to humid and swampy zones. The disease is associated with the creation or the extension of swampy areas, such as construction of dams or lakes for the development of agriculture. Currently, it is supposed that insects (water bugs and mosquitoes) are host and vector of M. ulcerans. The role of water bugs was clearly demonstrated by several experimental and environmental studies. However, no definitive conclusion can yet be drawn concerning the precise importance of this route of transmission. Concerning the mosquitoes, DNA was detected only in mosquitoes collected in Australia, and their role as host/vector was never studied by experimental approaches. Surprisingly, no specific study was conducted in Africa. In this context, the objective of this study was to investigate the role of mosquitoes (larvae and adults) and other flying insects in ecology of M. ulcerans. This study was conducted in a highly endemic area of Benin. METHODOLOGY/PRINCIPAL FINDINGS: Mosquitoes (adults and larvae) were collected over one year, in Buruli ulcer endemic in Benin. In parallel, to monitor the presence of M. ulcerans in environment, aquatic insects were sampled. QPCR was used to detected M. ulcerans DNA. DNA of M. ulcerans was detected in around 8.7% of aquatic insects but never in mosquitoes (larvae or adults) or in other flying insects. CONCLUSION/SIGNIFICANCE: This study suggested that the mosquitoes don't play a pivotal role in the ecology and transmission of M. ulcerans in the studied endemic areas. However, the role of mosquitoes cannot be excluded and, we can reasonably suppose that several routes of transmission of M. ulcerans are possible through the world.


Asunto(s)
Úlcera de Buruli/microbiología , Úlcera de Buruli/transmisión , Insectos Vectores/microbiología , Insectos/microbiología , Mycobacterium ulcerans/fisiología , Animales , Benin/epidemiología , ADN Bacteriano/aislamiento & purificación , Ecosistema , Humanos , Insectos Vectores/fisiología , Insectos/clasificación , Insectos/fisiología , Larva , Reacción en Cadena de la Polimerasa/métodos , Estaciones del Año
11.
Braz J Biol ; 74(1): 191-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25055101

RESUMEN

This study reports the occurrence and the effect of the environmental factors on the spatial and temporal distribution of the dinoflagellate Akashiwo sanguinea (Hirasaka) Hansen & Moestrup in estuarine waters of northeastern Brazil. Samples were collected at seven stations from March 2007 to February 2008 during high tide and low tide, using Van Dorn bottles. The samples were immediately fixed with Lugol and analyzed with the Utermöhl method. Water samples were also collected for the identification of the hydrological characteristics of the area. Akashiwo sanguinea occurred throughout the annual cycle and at all sampling sites with densities ranging between 5 and 410 x 103 cells.L-1. The highest densities were recorded at low tide, especially during the months of the rainy season (July: 210 x 103 cells.L-1; August: 410 x 103 cells.L-1). Density values were within the normal range and blooms were not detected. Despite being common in the area, the species showed preference for sites with high concentrations of orthophosphate and total dissolved phosphorus and with salinity in the mesohaline regime.


Asunto(s)
Dinoflagelados/clasificación , Brasil , Monitoreo del Ambiente/métodos , Estuarios , Densidad de Población , Dinámica Poblacional , Estaciones del Año
12.
Braz. j. biol ; 74(1): 191-198, 2/2014. tab, graf
Artículo en Inglés | LILACS | ID: lil-715578

RESUMEN

This study reports the occurrence and the effect of the environmental factors on the spatial and temporal distribution of the dinoflagellate Akashiwo sanguinea (Hirasaka) Hansen & Moestrup in estuarine waters of northeastern Brazil. Samples were collected at seven stations from March 2007 to February 2008 during high tide and low tide, using Van Dorn bottles. The samples were immediately fixed with Lugol and analyzed with the Utermöhl method. Water samples were also collected for the identification of the hydrological characteristics of the area. Akashiwo sanguinea occurred throughout the annual cycle and at all sampling sites with densities ranging between 5 and 410 x 103 cells.L–1. The highest densities were recorded at low tide, especially during the months of the rainy season (July: 210 x 103 cells.L–1; August: 410 x 103 cells.L–1). Density values were within the normal range and blooms were not detected. Despite being common in the area, the species showed preference for sites with high concentrations of orthophosphate and total dissolved phosphorus and with salinity in the mesohaline regime.


Este estudo relata a ocorrência e o efeito dos fatores ambientais na distribuição espacial e temporal do dinoflagelado Akashiwo sanguinea (Hirasaka) Hansen et Moestrup em águas estuarinas do Nordeste do Brasil. As amostras foram coletadas em sete estações, durante o período de março 2007 a fevereiro 2008 durante os regimes de preamar e baixa-mar, com o auxílio de garrafas tipo Van Dorn. As amostras foram imediatamente fixadas com lugol e analisadas pelo método de Utermöhl. Amostras de água foram também coletadas para a identificação das características hidrológicas da área. Akashiwo sanguinea ocorreu em todo o ciclo anual e em todos os locais de coleta com densidade variando de 5 a 410 cells.L–1 x 103, sendo as maiores densidades registradas na baixa-mar, principalmente, durante os meses do período chuvoso (julho 210 cells.L–1 x 103, agosto 410 cells.L–1 x 103). Os valores quantitativos estiveram dentro dos padrões normais, não tendo sido detectados florescimentos com conotações de blooms. Apesar de ser frequente na área, a espécie mostrou preferência pelos locais com maiores concentrações de ortofosfato dissolvido e fósforo total dissolvido e salinidade compreendida no regime mesoalino.


Asunto(s)
Dinoflagelados/clasificación , Brasil , Estuarios , Monitoreo del Ambiente/métodos , Densidad de Población , Dinámica Poblacional , Estaciones del Año
13.
Afr J Med Med Sci ; 43 Suppl: 117-24, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26949789

RESUMEN

BACKGROUND: Tuberculosis (TB) is a major public health. problem in Liberia and it is among the first five most important infectious diseases. Fourteen years of civil war in Liberia caused a large internal displacement and external migration of its citizens to neighbouring countries such as Guinea, Ivory Coast, Sierra Leone, Ghana and Nigeria. Current spatio-temporal pattern of TB cases in Liberia is essential for identifying risk factors among humans for optimal resource allocation. METHODS: Surveillance data from January, 2008 to December, 2012 were retrieved from two national TB referral hospitals in the country: TB Annex Hospital (TBAH) (Montserrado County) and Ganta TB and Leprosy Rehabilitation Hospital (GTBLRH) (Nimba County). Geographic coordinates of TB patient's locations were captured based on records in the hospital case-files using Global Positioning System (GPS). The coordinates were mapped using Geographic Information Systems (GIS) software. Data on age, gender, date of illness, dry and wet season frequency were used to compute a descriptive and categorical analysis. Kulldorff's spatio-temporal scan statistic was used to identify clusters of TB in the two Counties. RESULTS: A total of 2,890 laboratory-confirmed cases were reported during the study period. There were 1,365 (47.23%) and 1,525 (52.77%) cases from TBAH and GTBLRH respectively. The mean age of patient was 45.19 years ± 19.49 (SD). Of this, 1,450 (50.17%) were male. There was significant association between year of TB occurrence and treatment outcome (χ2 = 14.38; p = 0.006). CONCLUSION: The paper presents TB spatial pattern, summarizing 5-year records of post-conflict surveillance of the disease in Liberia.


Asunto(s)
Sistemas de Información Geográfica , Mycobacterium tuberculosis/aislamiento & purificación , Salud Pública , Medición de Riesgo/métodos , Tuberculosis/microbiología , Femenino , Humanos , Liberia/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estaciones del Año , Tuberculosis/epidemiología
14.
Clin Microbiol Infect ; 19(10): 970-4, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23331372

RESUMEN

Leprosy continues to be a significant health problem in certain pockets in developing countries. Better understanding of the transmission and source of the infection would help to decipher the transmission link, leading to control of the spread of the disease. The nose is considered to be a portal of entry, suggesting an aerial route for transmission through droplet infection. The evidence suggests that many individuals from endemic countries carry Mycobacterium leprae in their nasal cavities without having obvious symptoms of leprosy. The objective of the present study was to assess the presence of M. leprae on the nasal mucosa in the general population from a leprosy-endemic pocket. M. leprae detection was carried out using PCR targeting RLEP. Four hundred subjects from an area highly endemic for leprosy were included in the study and followed up during three different seasons--winter, summer, and monsoon--for evidence of nasal exposure to M. leprae. PCR positivity for M. leprae was observed in 29%, 21% and 31% of the samples collected in winter, summer and the monsoon season, respectively. Twenty-six individuals from the cohort showed amplification for M. leprae for all seasons. Our results are consistent with reports in the literature showing widespread exposure to M. leprae in the endemic community. The results also suggest possible association of the environmental conditions (climate) with the transmission pattern and levels of exposure to M. leprae. However, the present study indicated that the population from highly endemic pockets will have exposure to M. leprae irrespective of season.


Asunto(s)
Portador Sano/microbiología , Lepra/microbiología , Mycobacterium leprae/aislamiento & purificación , Mucosa Nasal/microbiología , Adolescente , Adulto , Anciano , Portador Sano/epidemiología , Niño , Preescolar , Estudios de Cohortes , ADN Bacteriano/análisis , ADN Bacteriano/genética , Enfermedades Endémicas , Femenino , Humanos , Humedad , India/epidemiología , Lepra/epidemiología , Masculino , Persona de Mediana Edad , Mycobacterium leprae/genética , Reacción en Cadena de la Polimerasa , Estaciones del Año , Adulto Joven
16.
J Dairy Sci ; 94(7): 3437-45, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21700029

RESUMEN

The objective was to determine whether transfer of fresh or vitrified embryos produced in vitro with sex-sorted semen improves pregnancy and calving rates during summer in lactating dairy cows compared with artificial insemination (AI). Lactating dairy cows (n=722) were enrolled during summer months at 2 commercial dairies in Central Texas and randomly assigned to 1 of 3 treatments: AI with conventional semen (n=227), embryo transfer-vitrified (ET-V; n=279) or embryo transfer-fresh (ET-F; n=216). Embryos were produced in vitro using sex-sorted semen and with Block-Bonilla-Hansen-7 culture medium. For vitrification, grade 1 expanded blastocysts were harvested on d 7 after fertilization and vitrified using the open-pulled straw method. Fresh embryos were grade 1 blastocysts and expanded blastocysts harvested on d 7 after fertilization. Cows were submitted to the Ovsynch56 protocol: d -10 GnRH, d -3 PGF(2α), d -1 GnRH and d 0 timed AI; or Select Synch protocol: d -9 GnRH, d -2 PGF(2α), and AI following detected estrus (day of AI=d 0). On d 7, all cows were examined for presence of a corpus luteum (CL). A vitrified or fresh embryo was transferred to cows with CL in ET-V and ET-F groups. Cows were considered synchronized if progesterone was <1ng/mL on d 0 and a CL was present on d 7. At d 40±7 of gestation, the percentage of cows pregnant was greater for the ET-F compared with the ET-V and AI groups among all cows (42.1 vs. 29.3 and 18.3%, respectively) and synchronized cows (45.5 vs. 31.6 and 24.8%, respectively). Also, the percentage of cows pregnant was greater for the ET-V than the AI group among all cows and tended to be greater among synchronized cows. At d 97±7 of gestation, the percentage of cows pregnant among all cows was greater for ET-F and ET-V groups than for the AI group (36.4 and 25.7 vs. 17.0%, respectively) and the percentage for the ET-F group was greater than for the ET-V group. Among synchronized cows, the percentage of cows pregnant was significantly increased for the ET-F group than for ET-V and AI groups (39.4 vs. 27.8 and 23.1%, respectively) and no difference was found between ET-V and AI groups. No effect of treatment on embryo loss was observed. The percentage of cows with live births was significantly increased for the ET-F than for ET-V and AI groups among all cows (27.5 vs. 17.1 and 14.6%, respectively) and synchronized cows (29.9 vs. 18.5 and 20.0%, respectively). The percentage of cows giving birth to a live heifer was significantly increased for the ET-F and ET-V groups compared with the AI group among all cows (79.1 and 72.5 vs. 50.0%, respectively) and synchronized cows (79.1 and 72.5 vs. 50.0%, respectively). No difference existed between ET-F and ET-V groups for percent live heifer births but both were greater than for the AI group. The transfer of fresh embryos produced in vitro using sex-sorted semen to lactating dairy cows during summer can effectively increase the percentage of cows that establish pregnancy and also the percentage of cows that give birth to a live heifer compared with percentages from AI with conventional semen.


Asunto(s)
Bovinos/fisiología , Transferencia de Embrión/veterinaria , Fertilización In Vitro/veterinaria , Lactancia , Estaciones del Año , Semen/citología , Preselección del Sexo/veterinaria , Animales , Transferencia de Embrión/métodos , Femenino , Inseminación Artificial/métodos , Inseminación Artificial/veterinaria , Embarazo , Índice de Embarazo , Texas
17.
Arch Ital Biol ; 148(3): 259-70, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21175012

RESUMEN

We explore functional connectivity in nine subjects measured with 1.5T fMRI-BOLD in a longitudinal study of recovery from unilateral stroke affecting the motor area (Small et al., 2002). We found that several measures of complexity of covariance matrices show strong correlations with behavioral measures of recovery. In Schmah et al. (2010), we applied Linear and Quadratic Discriminants (LD and QD) computed on a principal components (PC) subspace to classify the fMRI volumes into "early" and "late" sessions. We demonstrated excellent classification accuracy with QD but not LD, indicating that potentially important differences in functional connectivity exist between the early and late sessions. Motivated by Mclntosh et al. (2008), who showed that EEG brain-signal variability and behavioral performance both increased with age during development, we investigated complexity of the covariance matrix for this longitudinal stroke recovery data set. We used three complexity measures: the sphericity index described by Abdi (2010); "unsupervised dimensionality", which is the number of PCs that minimizes unsupervised generalization error of a covariance matrix (Hansen et al., 1999); and "QD dimensionality", which is the number of PCs that minimizes the classification accuracy of QD. Although these approaches measure different kinds of complexity, all showed strong correlations with one or more behavioral tests: nine-hole peg test, hand grip test and pinch test. We could not demonstrate that either sphericity or unsupervised dimensionality were significantly different for the "early" and "late" sessions using a paired Wilcoxon test. However, the amount of relative behavioral improvement was correlated with sphericity of the overall covariance matrix (pooled across all sessions), as well as with the divergence of the eigenspectra between the "early" and "late" covariance matrices. Complexity measures that use the number of PCs (which optimize QD classification or unsupervised generalization) were correlated with the behavioral performance of the final session, but not with the relative improvement. These are suggestive, but limited, results given the sample size, restricted behavioral measurements and older 1.5T BOLD data sets. Nevertheless, they indicate one potentially fruitful direction for future data-driven fMRI studies of stroke recovery in larger, better-characterized longitudinal stroke data sets recorded at higher field strength. Finally, we produced sensitivity maps (Kjems et al., 2002) corresponding to both linear and quadratic discriminants for the "early" vs. "late" classification. These maps measure the influence of each voxel on the class assignments for a given classifier. Differences between the scaled sensitivity maps for the linear and quadratic discriminants indicate brain regions involved in changes in functional connectivity. These regions are highly variable across subjects, but include the cerebellum and the motor area contralateral to the lesion.


Asunto(s)
Encéfalo/irrigación sanguínea , Encéfalo/fisiopatología , Recuperación de la Función/fisiología , Accidente Cerebrovascular/patología , Electroencefalografía/métodos , Fuerza de la Mano/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Estudios Longitudinales , Imagen por Resonancia Magnética/métodos , Pruebas Neuropsicológicas , Oxígeno/sangre , Análisis de Componente Principal , Reproducibilidad de los Resultados , Estaciones del Año , Sensibilidad y Especificidad , Estadística como Asunto , Accidente Cerebrovascular/fisiopatología , Factores de Tiempo
18.
PLoS Negl Trop Dis ; 4(7): e731, 2010 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-20625552

RESUMEN

BACKGROUND: Buruli ulcer, the third mycobacterial disease after tuberculosis and leprosy, is caused by the environmental mycobacterium M. ulcerans. Various modes of transmission have been suspected for this disease, with no general consensus acceptance for any of them up to now. Since laboratory models demonstrated the ability of water bugs to transmit M. ulcerans, a particular attention is focused on the transmission of the bacilli by water bugs as hosts and vectors. However, it is only through detailed knowledge of the biodiversity and ecology of water bugs that the importance of this mode of transmission can be fully assessed. It is the objective of the work here to decipher the role of water bugs in M. ulcerans ecology and transmission, based on large-scale field studies. METHODOLOGY/PRINCIPAL FINDINGS: The distribution of M. ulcerans-hosting water bugs was monitored on previously unprecedented time and space scales: a total of 7,407 water bugs, belonging to large number of different families, were collected over one year, in Buruli ulcer endemic and non endemic areas in central Cameroon. This study demonstrated the presence of M. ulcerans in insect saliva. In addition, the field results provided a full picture of the ecology of transmission in terms of biodiversity and detailed specification of seasonal and regional dynamics, with large temporal heterogeneity in the insect tissue colonization rate and detection of M. ulcerans only in water bug tissues collected in Buruli ulcer endemic areas. CONCLUSION/SIGNIFICANCE: The large-scale detection of bacilli in saliva of biting water bugs gives enhanced weight to their role in M. ulcerans transmission. On practical grounds, beyond the ecological interest, the results concerning seasonal and regional dynamics can provide an efficient tool in the hands of sanitary authorities to monitor environmental risks associated with Buruli ulcer.


Asunto(s)
Vectores de Enfermedades , Heterópteros/microbiología , Mycobacterium ulcerans/aislamiento & purificación , Animales , Úlcera de Buruli/transmisión , Camerún , Modelos Animales de Enfermedad , Femenino , Geografía , Humanos , Ratones , Ratones Endogámicos BALB C , Saliva/microbiología , Estaciones del Año
19.
Environ Sci Technol ; 42(3): 884-9, 2008 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-18323117

RESUMEN

A generally accepted method to measure black carbon (BC) or elemental carbon (EC) still does not exist. An earlier study in the Vienna area comparing practically all measurement methods in use in Europe gave comparable BC and EC concentrations under summer conditions (Hitzenberger et al., 2006a). Under summer conditions, Diesel traffic is the major source for EC or BC in Vienna. Under winter conditions, space heating (also with biomass as fuel) is another important source (Caseiro et al., 2007). The present study compares the response of thermal methods (a modified Cachier method, Cachier et al., 1989; a thermal-optical method, Schmid et al., 2001; and two thermal-optical (TOT) methods using Sunset instruments, Birch and Cary, 1996 and Schauer et al., 2003) and optical methods (a light transmission method, Hansen et al., 1984; the integrating sphere method, Hitzenberger et al., 1996; and the multiangle absorption photometer MAAP, Petzold and Schönlinner, 2004). Significant differences were found between the TOT methods on the one hand and all other methods on the other. The TOT methods yielded EC concentrations that were lower by 44 and 17% than the average of all measured concentrations (including the TOT data). The largest discrepancy was found when the contribution of brown carbon (measured with the integrating sphere method) was largest.


Asunto(s)
Biomasa , Carbono/análisis , Técnicas de Química Analítica/métodos , Ciudades , Estaciones del Año , Absorción , Temperatura
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