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1.
Sci Rep ; 14(1): 22415, 2024 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-39341864

RESUMEN

Urban and roadside trees contribute to health and resilience. However, when trees or branches fall, it can cause injuries or deaths. This study examined trends and variations of injuries and deaths due to tree failure in The Netherlands from 1998 to 2021, considering urban-rural location, sex, age and traffic mode. This study is the first to describe long-term trends in injuries and deaths due to tree failure from 1998-2021. The standardised rate of injuries per 1,000,000 population increased from 0.14 (SE 0.10) in 1998 to 0.91 (SE 0.21) in 2021, with an annual percentage increase of 5.3% (p = 0.002). The data shows a strong increase for rural areas, contrary to urban ones. The annual percentage increase in rural areas was 13.2% (p < 0.001) while injuries in urban areas increased with 3.0% (p = 0.026), which revealed large urban-rural disparities. A trend was absent in the frequency of deaths. More attention needs to be given to investigating causes, drivers and stressors associated with tree failure-related injuries. In particular, efforts should be made to reduce the prevalence in rural areas. The increase in injuries over time makes it necessary to create awareness and share knowledge among residents and local governments about tree failure risks.


Asunto(s)
Accidentes de Tránsito , Árboles , Heridas y Lesiones , Humanos , Países Bajos/epidemiología , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Adolescente , Heridas y Lesiones/mortalidad , Heridas y Lesiones/epidemiología , Accidentes de Tránsito/mortalidad , Accidentes de Tránsito/estadística & datos numéricos , Población Rural , Población Urbana , Adulto Joven , Niño , Preescolar , Lactante , Anciano de 80 o más Años
3.
Rev Neurol ; 67(6): 203-209, 2018 Sep 16.
Artículo en Español | MEDLINE | ID: mdl-30183060

RESUMEN

INTRODUCTION: After Zika virus outbreak and the increase in the incidence of Guillain-Barre syndrome (GBS), the causal relationship has been studied, however a full etiological correlation has not been found. PATIENTS AND METHODS: From January 1 to December 31, 2017, patients with GBS were included. In addition to the basic serologies, enterovirus, herpes, Campylobacter, hepatitis B and C, TORCH, HIV, Brucella and Salmonella were requested. RESULTS: Cohort of seven male patients. Five patients analyzed cerebrospinal fluid reporting normal; all of them underwent brain scan, reporting normal. Neuroconduction was performed, resulting in acute inflammatory demyelinating polyneuropathy in four cases and acute motor axonal neuropathy in one case. All received intravenous immunoglobulins, five cases had a good prognosis and two deaths. No positive cases were reported to Zika virus. A positive case was reported to dengue and another to chikungunya. Five positive cases were reported to Campylobacter. One case positive to enterovirus. Dengue + Campylobacter coinfections were reported in one case and chikungunya + Campylobacter in another case. CONCLUSIONS: The present cohort shows that it was not possible to establish a causal relationship between GBS and Zika virus, but other viral and bacterial causal agents were identified, such as dengue, chikungunya and enterovirus, with the identification of Campylobacter cases even more remarkable.


TITLE: Agentes causales mas frecuentes del sindrome de Guillain-Barre en un hospital de Veracruz, Mexico.Introduccion. Con posterioridad a la oleada del virus del Zika y el incremento en la incidencia de sindrome de Guillain-Barre (SGB), se ha estudiado la relacion causal, pero no se ha encontrado una plena correlacion etiologica. Pacientes y metodos. Del 1 de enero al 31 de diciembre de 2017, se incluyeron pacientes con SGB. Ademas de las serologias basicas, se solicitaron determinaciones de enterovirus, virus del herpes, Campylobacter, hepatitis B y C, TORCH, virus de la inmunodeficiencia humana, Brucella y Salmonella. Resultados. Cohorte de siete pacientes de sexo masculino. A cinco pacientes se les analizo el liquido cefalorraquideo, que era normal. A todos se les realizo una tomografia encefalica, tambien normal, y se realizo neuroconduccion, que mostro polineuropatia inflamatoria desmielinizante aguda en cuatro casos y neuropatia motora axonal aguda en uno. Todos recibieron inmunoglobulinas intravenosas; tuvieron buen pronostico cinco casos y hubo dos defunciones. No se informo de casos positivos al virus del Zika. Hubo un caso positivo al dengue, uno al chikungunya, cinco a Campylobacter y uno a enterovirus. Se informo de coinfecciones de dengue + Campylobacter en un caso y de chikungunya + Campylobacter en otro. Conclusiones. La presente cohorte demuestra que no fue posible establecer una relacion causal entre el SGB y el virus del Zika, pero se identificaron otros agentes causales viricos y bacterianos, como dengue, chikungunya y enterovirus, y fue aun mas destacable la identificacion de los casos de Campylobacter.


Asunto(s)
Síndrome de Guillain-Barré/microbiología , Adulto , Anciano de 80 o más Años , Estudios Transversales , Síndrome de Guillain-Barré/diagnóstico , Hospitales Generales , Humanos , Masculino , México , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
5.
J Phys Chem A ; 121(40): 7667-7674, 2017 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-28902518

RESUMEN

We report the first direct kinetic study of the gas-phase reaction NaOH + H → Na + H2O, which is central to the chemistry of sodium in the upper atmosphere and in flames. The reaction was studied in a fast flow tube, where NaOH was observed by multiphoton ionization and time-of-flight mass spectrometry, yielding k(NaOH + H, 230-298 K) = (3.8 ± 0.8) × 10-11 cm3 molecule -1 s-1 (at 2σ confidence level), showing no significant temperature dependence over the indicated temperature range and essentially in agreement with previous estimates of the rate constant in hydrogen-rich flames. We show, using theoretical trajectory calculations, that the unexpectedly slow, yet T-independent, rate coefficient for NaOH + H is explained by severe constraints in the angle of attack that H can make on NaOH to produce H2O. This reaction is also central to explaining Na-catalyzed flame inhibition, which has been proposed to occur via the sequence Na + OH (+ M) → NaOH followed by NaOH + H → Na + H2O, thereby effectively recombinating H and OH to H2O. RRKM calculations for the recombination of Na and OH yield k(Na + OH + N2, 300-2400 K) = 2.7 × 10-29 (300/T)1.2 cm6 molecule-2 s-1, in agreement with a previous flash photolysis measurement at 653 K and Na-seeded flame studies in the 1800-2200 K range. These results therefore provide strong evidence to support the mechanism of flame inhibition by Na.

6.
J Econ Entomol ; 108(1): 245-51, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26470126

RESUMEN

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), is a major pest of citrus worldwide due to its ability to transmit the bacteria associated with huanglongbing. Vision, behavior, and performance of insect pests can be manipulated by using ultraviolet (UV)-blocking materials. Thus, the aim of our study was to evaluate how UV-blocking plastic films may affect the take-off and host plant finding ability of D. citri. To assess the effect of a UV-deficient environment on take-off, adult psyllids were released from a vial inside a screenhouse covered by a UV-blocking or standard (control) film and the number of insects remaining on each vial under each treatment was counted at different time intervals. Moreover, to assess the ability of D. citri to find citrus plants under a UV-deficient environment, two independent no-choice host plant finding assays with different plant arrangements were conducted. In each treatment, the number of psyllids per plant at different time intervals was counted. Both D. citri take-off and host plant finding ability was clearly disrupted under a UV-deficient environment. The number of psyllids remaining in the vials was significantly higher under UV-blocking than standard film in all periods recorded. Furthermore, psyllids were present in significantly higher number on citrus plants under standard film than under UV-blocking film in all of the periods assessed and experiments conducted. Our results showed that UV-blocking materials could become a valuable strategy for integrated management of D. citri and huanglongbing in citrus grown in enclosed environments.


Asunto(s)
Hemípteros/efectos de la radiación , Control de Insectos/métodos , Animales , Plásticos , Rayos Ultravioleta
7.
Rev. bras. plantas med ; 17(3): 436-443, Jul-Sep/2015. tab
Artículo en Portugués | LILACS | ID: lil-752553

RESUMEN

RESUMO Camellia sinensis é amplamente conhecida por seus efeitos benéficos à saúde humana. Dentre as diversas formas de processamento desta erva, o chá verde e chá preto são os mais populares. Neste trabalho objetivou-se avaliar os teores de fenólicos totais e flavonoides em amostras de 25 diferentes marcas disponíveis à venda em farmácias e supermercados de Salvador-Ba. Os resultados obtidos apresentaram diferenças significativas na concentração dos compostos fenólicos entre as marcas de chá verde estudadas. No estudo também ficou comprovado que, no preparo do chá verde, as amostras obtidas por infusão aquosa com agitação mecânica apresentaram maiores teores de polifenóis e flavonoides em relação àquelas que não foram submetidas à agitação.


ABSTRACT Camellia sinensis is widely known for its beneficial effects to human health. Among the various forms of processing this herb, the green and the black tea are the most popular ones. The objective of this work was to evaluate the contents of total polyphenol and flavonoids in samples of 25 different brands available for sale in pharmacies and supermarkets of Salvador-Ba. The results showed great variation in the concentration of phenolic compounds among the brands of green tea which were tested. In the study it was also proven that in the green tea preparation the samples obtained by mechanical agitation with aqueous infusion showed higher levels of phenolics and flavonoids contents than those which were not subjected to stirring.


Asunto(s)
Flavonoides/análisis , Camellia sinensis/metabolismo , Polifenoles/análisis , Antioxidantes/farmacología
8.
Phys Chem Chem Phys ; 15(32): 13513-22, 2013 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-23823942

RESUMEN

From a kinetics standpoint, reactive molecular collisions are the building blocks of the mechanisms of chemical reactions. In contrast, a dynamics standpoint reveals molecular collisions to have their own internal mechanisms, which are not mere theoretical abstractions: through suitable preparation of the reactants internal and stereochemical states, features of the mechanisms of a reactive molecular collision can be made evident and used as "handles" to control the reaction outcome. Using time-independent quantum dynamical calculations, we demonstrate this for the Br + H2(v = 0-1, j = 2) → H + HBr reaction in the 1.0-1.6 eV range of total energies. Despite its pronounced effect on reactivity, which is in agreement with the predictions from Polanyi rules, reactant vibration is found to have little effect on the mechanism of this endoergic, late-barrier reaction. Analysis of the correlations between directional reaction properties shows that the collision stereochemistry strongly depends on the total energy, but not on how this energy is partitioned between reactant translation and vibration. The stereodynamical preferences implied by the collision mechanisms determine how and to what extent one can control the reaction. Regarding the overall reaction, the extent of control is found to be large near the reaction threshold but not when the total energy is high. Regarding state-to-state reactions, the effect of reactant stereochemistry on the product rotational state distribution is found to be nontrivial and energy dependent.


Asunto(s)
Bromuros/química , Bromo/química , Hidrógeno/química , Teoría Cuántica , Estereoisomerismo
9.
J Chem Phys ; 138(10): 104309, 2013 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-23514491

RESUMEN

Rotational angular momentum alignment effects in the rotational inelastic scattering of NO(X) with Ar have been investigated by means of close-coupled quantum mechanical, quasi-classical trajectory, and Monte Carlo hard shell scattering calculations. It has been shown that the hard shell nature of the interaction potential at a collision energy of Ecoll = 66 meV is primarily responsible for the rotational alignment of the NO(X) molecule after collision. By contrast, the alternating trend in the quantum mechanical parity resolved alignment parameters with change in rotational state Δj reflects differences in the differential cross sections for NO(X) parity conserving and changing collisions, rather than an underlying difference in the collision induced rotational alignment. This suggests that the rotational alignment and the differential cross sections are sensitive to rather different aspects of the scattering dynamics. The applicability of the kinematic apse model has also been tested and found to be in excellent agreement with exact quantum mechanical scattering theory provided the collision energy is in reasonable excess of the well depth of the NO(X)-Ar potential energy surface.

10.
Transplant Proc ; 44(8): 2397-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23026604

RESUMEN

INTRODUCTION: Some special situations may require aortic clamping during pancreas transplantation (PT). The most important problem is ischemic injury to a previous transplanted kidney. We sought to demonstrate experience with aortic clamping in PT without special kidney allograft protection measures and its impact on kidney function. METHODS: Retrospective study that analyzed 6 patients who underwent PT (5 pancreas after kidney and 1 simultaneous pancreas-kidney) with aortic clamping. In all cases, the pancreas graft was placed on the right with retrocolic portal-enteric drainage. Serum creatinine was evaluated pre- and posttransplantation. RESULTS: The average clamping time was 19 minutes. The mean serum creatinine was 1.1, 1.15, 0.95, and 1.0, respectively, at pre and postoperative days 1 and 7 and at hospital discharge. Patient, kidney, and pancreatic graft survivals were 100%, 100%, and 83%, respectively. CONCLUSION: The need for aortic clamping in selected cases of PT did not seem to affect the transplanted kidney, even without protective measures, provided that the ischemic time was short.


Asunto(s)
Aorta/cirugía , Trasplante de Riñón , Trasplante de Páncreas/métodos , Procedimientos Quirúrgicos Vasculares , Adulto , Biomarcadores/sangre , Constricción , Creatinina/sangre , Femenino , Supervivencia de Injerto , Humanos , Trasplante de Riñón/efectos adversos , Masculino , Persona de Mediana Edad , Trasplante de Páncreas/efectos adversos , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/efectos adversos , Isquemia Tibia
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