Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
1.
Proc Natl Acad Sci U S A ; 115(14): 3529-3537, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29555739

RESUMEN

Population numbers at local levels are fundamental data for many applications, including the delivery and planning of services, election preparation, and response to disasters. In resource-poor settings, recent and reliable demographic data at subnational scales can often be lacking. National population and housing census data can be outdated, inaccurate, or missing key groups or areas, while registry data are generally lacking or incomplete. Moreover, at local scales accurate boundary data are often limited, and high rates of migration and urban growth make existing data quickly outdated. Here we review past and ongoing work aimed at producing spatially disaggregated local-scale population estimates, and discuss how new technologies are now enabling robust and cost-effective solutions. Recent advances in the availability of detailed satellite imagery, geopositioning tools for field surveys, statistical methods, and computational power are enabling the development and application of approaches that can estimate population distributions at fine spatial scales across entire countries in the absence of census data. We outline the potential of such approaches as well as their limitations, emphasizing the political and operational hurdles for acceptance and sustainable implementation of new approaches, and the continued importance of traditional sources of national statistical data.


Asunto(s)
Censos , Emigrantes e Inmigrantes/estadística & datos numéricos , Vivienda , Modelos Teóricos , Densidad de Población , Dinámica Poblacional , Países en Desarrollo , Humanos
2.
Indoor Air ; 26(2): 207-18, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25858592

RESUMEN

Indoor mold odor is associated with adverse health effects, but the microbial volatiles underlying mold odor are poorly described. Here, chloroanisoles were studied as potential key players, being formed by microbial metabolism of chlorophenols in wood preservatives. Using a three-stage approach, we (i) investigated the occurrence of chloroanisoles in buildings with indoor air quality problems, (ii) estimated their frequency in Sweden, and (iii) evaluated the toxicological risk of observed chloroanisole concentrations. Analyses of 499 building materials revealed several chloroanisole congeners in various types of buildings from the 1950s to 1970s. Evaluation of Swedish records from this time period revealed three coinciding factors, namely an unprecedented nationwide building boom, national regulations promoting wood preservatives instead of moisture prevention, and use of chlorophenols in these preservatives. Chlorophenols were banned in 1978, yet analysis of 457 indoor air samples revealed several chloroanisole congeners, but at median air levels generally below 15 ng/m(3) . Our toxicological evaluation suggests that these concentrations are not detrimental to human health per se, but sufficiently high to cause malodor. Thereby, one may speculate that chloroanisoles in buildings contribute to adverse health effects by evoking odor which, enhanced by belief of the exposure being hazardous, induces stress-related and inflammatory symptoms.


Asunto(s)
Microbiología del Aire , Contaminación del Aire Interior/análisis , Anisoles/análisis , Monitoreo del Ambiente , Odorantes/análisis , Contaminación del Aire Interior/estadística & datos numéricos , Humanos , Suecia
3.
Arch Toxicol ; 88(5): 1127-40, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24714767

RESUMEN

The content of aromatic hydrocarbons in solvent mixtures, such as white spirits (WS), has been assumed a major contributor to the neurotoxic effects of these compounds. Hence, dearomatized WS have been introduced to the market rapidly in the last decade. Studies investigating other aromatic hydrocarbons (toluene) and animal models have supported the aforementioned assumption, but the current study is the first one to compare acute neurobehavioral effects of exposure to aromatic and dearomatized WS (aWS, daWS) content in human volunteers at current occupational exposure limit values. In a pseudo-randomized crossover design, six female and six male healthy volunteers were exposed to aWS and daWS at two concentrations (100 and 300 mg/m(3)) and to clean air for 4 h at rest. During each of the five exposure conditions, volunteers performed five neurobehavioral tasks that were selected following a multidisciplinary approach that accounted for findings from the cognitive neurosciences and mechanisms of solvent toxicity. Two of the tasks indicated performance changes during aromatic WS exposure, the working memory (WM) and the response shifting task, but both effects are difficult to interpret due to low mean accuracy in the WM task and due to a lack of dose-response relationship in the response shifting task. Healthy human volunteers showed weak and inconsistent neurobehavioral impairment after 4-h exposures to 100 and 300 mg/m(3) aromatic or dearomatized WS. Our multidisciplinary approach of selecting neurobehavioral test methods may guide the test selection strategies in future studies.


Asunto(s)
Hidrocarburos/química , Hidrocarburos/toxicidad , Adulto , Atención/efectos de los fármacos , Cognición/efectos de los fármacos , Visión de Colores/efectos de los fármacos , Femenino , Humanos , Hidrocarburos/administración & dosificación , Exposición por Inhalación , Masculino , Memoria a Corto Plazo/efectos de los fármacos , Síndromes de Neurotoxicidad/fisiopatología , Solventes/administración & dosificación , Solventes/química , Solventes/toxicidad
4.
J Plast Surg Hand Surg ; 51(4): 270-274, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27844485

RESUMEN

INTRODUCTION: Obtaining quality global statistics about surgical procedures remains an important yet challenging task. The International Society of Aesthetic Plastic Surgery (ISAPS) reports the total number of surgical and non-surgical procedures performed worldwide on a yearly basis. While providing valuable insight, ISAPS' statistics leave two important factors unaccounted for: (1) the underlying base population, and (2) the number of surgeons performing the procedures. METHODS: Statistics of the published ISAPS' 'International Survey on Aesthetic/Cosmetic Surgery' were analysed by country, taking into account the underlying national base population according to the official United Nations population estimates. Further, the number of surgeons per country was used to calculate the number of surgeries performed per surgeon. RESULTS: In 2014, based on ISAPS statistics, national surgical procedures ranked in the following order: 1st USA, 2nd Brazil, 3rd South Korea, 4th Mexico, 5th Japan, 6th Germany, 7th Colombia, and 8th France. When considering the size of the underlying national populations, the demand for surgical procedures per 100,000 people changes the overall ranking substantially. It was also found that the rate of surgical procedures per surgeon shows great variation between the responding countries. CONCLUSION: While the US and Brazil are often quoted as the countries with the highest demand for plastic surgery, according to the presented analysis, other countries surpass these countries in surgical procedures per capita. While data acquisition and quality should be improved in the future, valuable insight regarding the demand for surgical procedures can be gained by taking specific demographic and geographic factors into consideration.


Asunto(s)
Cirugía Plástica/estadística & datos numéricos , Brasil , Femenino , Encuestas de Atención de la Salud , Humanos , Internacionalidad , Corea (Geográfico) , Masculino , Modelos Estadísticos , Cirugía Plástica/normas , Estados Unidos
5.
Schizophr Res ; 76(1): 25-41, 2005 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-15927796

RESUMEN

Mismatch negativity (MMN) is an event-related potential measure of auditory change detection. It is widely reported to be smaller in patients with schizophrenia and may not improve along with otherwise successful clinical treatment. The main aim of this report is to explore ways of measuring and presenting four features of frequency-deviant MMN dipole sources (dipole moment, peak latency, brain location and orientation) and to relate these to the processes of psychopathology and illness progression. Data from early onset patients (EOS) at the start of the illness in adolescence, and others who had their first break in adolescence 15 years ago (S-15Y) were compared with two groups of age-matched healthy controls (C-EOS, C-15Y). A four-source model fitted the MMN waveform recorded from all four groups, whether MMN amplitude was more (EOS) or less (S-15Y) reduced. The locations were in the left superior temporal and anterior cingulate gyri, right superior temporal and inferior/mid frontal cortices. Dipole latencies confirmed a bottom-up sequence of processing and dipole moments were larger in the temporal lobes and on the left. Patients showed small dipole location changes that were more marked in the S-15Y than the EOS group (more rostral for the left anterior cingulate, more caudal for the right mid-frontal dipole) consistent with illness progression. The modelling of MMN dipole sources on brain atlas and anatomical images suggests that there is a degree of dissociation during illness between small progressive anatomical changes and some functional recovery indexed by scalp recordings from patients with an onset in adolescence 15 years before compared to adolescents in their first episode.


Asunto(s)
Variación Contingente Negativa/fisiología , Potenciales Evocados Auditivos/fisiología , Lóbulo Frontal/fisiopatología , Esquizofrenia/diagnóstico , Psicología del Esquizofrénico , Lóbulo Temporal/fisiopatología , Adolescente , Adulto , Atención/fisiología , Mapeo Encefálico , Enfermedad Crónica , Progresión de la Enfermedad , Dominancia Cerebral/fisiología , Electroencefalografía , Femenino , Giro del Cíngulo/fisiopatología , Humanos , Masculino , Valores de Referencia , Esquizofrenia/fisiopatología , Sensibilidad y Especificidad
6.
Water Sci Technol ; 51(3-4): 283-90, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15850201

RESUMEN

Nutrient emissions by point and diffuse sources were estimated for 388 sub-catchments of the Danube river basin for the period 1998-2000 by means of the Model MONERIS. For nitrogen total emissions of 684 kt/a N were estimated for the Danube basin. 80% of these emissions were caused by diffuse sources (mainly groundwater, urban areas and tile drainage). For phosphorus the emission was 57 kt/a P, with a contribution of diffuse sources to this sum of 58%. The comparison of calculated and observed loads shows that the mean deviation for the investigated sub-catchments of the Danube river basin is 20% for dissolved inorganic nitrogen and 34% for phosphorus. The spatial resolution of the emission calculations allows the identification of regional hot spots and the derivation of specific regional measures to reduce the emissions into the Danube and consequently into the Western Black Sea.


Asunto(s)
Modelos Teóricos , Nitrógeno/análisis , Fósforo/análisis , Ríos/química , Contaminantes Químicos del Agua/análisis , Conservación de los Recursos Naturales , Monitoreo del Ambiente , Europa (Continente) , Reproducibilidad de los Resultados , Movimientos del Agua , Abastecimiento de Agua
7.
J Psychol Human Sex ; 7(3): 39-60, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-12320382

RESUMEN

PIP: To evaluate gender differences in the subjective experience and use of condoms, 193 heterosexual patrons at 13 bars in New York City were interviewed on site in 1991. Most respondents were single, middle class, and White; their ages ranged from 18 to 51 years. The data analysis was restricted to the 155 men and women who had at least 1 new partner in the 3 years preceding the survey. Respondents worried most about acquired immunodeficiency syndrome (AIDS) when engaging in sex with a new partner. 86% indicated concern about AIDS had affected their sexual behavior, most often by increasing their condom use and decreasing casual sex. 91% of women and 79% of men said that condoms give them greater peace of mind. Women worried more than men about AIDS when they had a new sexual partner and were more likely to limit their number of partners, work harder on an existing sexual relationship, give up casual sex, or give up sex with new partners. Men's subjective condom experiences were related to their penile functioning (erection and ejaculation) and the threat of loss of sexual pleasure. Multiple regression equations revealed that, among men, condom use with new partners was associated with worrying about AIDS and younger age; among women, peace of mind was a positive predictor. With casual partners, more partners led to increased condom use among women and worrying about AIDS was a predictor for men; peace of mind was predictive for both genders. 53% of men compared to 21% of women expected to meet a new sexual partner at the bar where they were interviewed, and 36% of men and 19% of women were carrying condoms with them.^ieng


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Adulto , Condones , Miedo , Infecciones por VIH , Conductas Relacionadas con la Salud , Relaciones Interpersonales , Factores Sexuales , Conducta Sexual , Parejas Sexuales , Persona Soltera , Factores de Edad , Américas , Conducta , Anticoncepción , Demografía , Países Desarrollados , Enfermedad , Emociones , Servicios de Planificación Familiar , Estado Civil , Matrimonio , New York , América del Norte , Población , Características de la Población , Psicología , Investigación , Estados Unidos , Virosis
8.
Br J Plast Surg ; 55(5): 430-3, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12372374

RESUMEN

Spermine/nitric oxide complex (Sper/NO) is a new nitric oxide (NO) donor with a long half-life providing controlled biological release of NO in vivo. The purpose of this study was to determine whether flap survival could be improved by pre-ischaemic or post-ischaemic intravenous administration of Sper/NO. We divided 37 male Wistar rats into four experimental groups. An extended epigastric adipocutaneous flap was raised in each animal. The mean area of flap necrosis was assessed for all groups on the fifth postoperative day, using planimetry software. The average area of flap necrosis was mean +/- s.d. = 68.2%+/-18.1% in the control group, and 29.7% +/- 13.3% in the non-ischaemic controls. The group with pre-ischaemic application of Sper/NO demonstrated an average flap necrosis of mean+/-s.d. = 11.2%+/-5.9%, whereas this increased to 59.2%+/-14.4% in the group receiving Sper/NO 5 min prior to reperfusion. The group with pre-ischaemic application of Sper/NO showed a significantly lower area of flap necrosis than either of the control groups or the group receiving Sper/NO just prior to reperfusion (P < 0.05). The group receiving Sper/NO just prior to reperfusion demonstrated a significantly higher mean area of flap necrosis than the non-ischaemic controls (P < 0.05), but did not differ significantly from the control group. Our data show that pharmacological preconditioning and enhancement of flap survival can be achieved by intravenous administration of Sper/NO. The application of Sper/NO at the end of the ischaemia period or in the early reperfusion period provides no protection against ischaemia-reperfusion injury.


Asunto(s)
Supervivencia de Injerto/efectos de los fármacos , Donantes de Óxido Nítrico/farmacología , Espermina/análogos & derivados , Espermina/administración & dosificación , Colgajos Quirúrgicos/fisiología , Animales , Masculino , Necrosis , Óxidos de Nitrógeno , Ratas , Ratas Wistar , Espermina/farmacología , Colgajos Quirúrgicos/patología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA