Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 132
Filtrar
1.
Diagn Microbiol Infect Dis ; 109(2): 116215, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38493509

RESUMO

BACKGROUND: Antibiotic therapy for patients with early Lyme disease is necessary to prevent later-stage Lyme disease complications. This systematic review and meta-analysis compares shorter versus longer antibiotic regimens in treating early Lyme disease. METHODS: A systematic search of PubMed, Embase, and Cochrane Central Register of Controlled Trials was conducted up to November 2023. We examined treatment failure, complete response, and photosensitivity. Short vs. long therapy was defined as ≤10 days vs. >10 days. Subgroup analyses included antibiotic type and varying treatment durations. Analysis utilized RStudio 4.1.2. PROSPERO registration: CRD42023423876. RESULTS: Seven studies, encompassing 1,462 patients, were analyzed. No significant differences in treatment failure, 12-month complete response, final visit complete response were found between short and long durations of antibiotic therapy. Subgroup and sensitivity analyses corroborated these findings. CONCLUSION: Shorter and longer antibiotic regimens for early Lyme disease show similar efficacy, highlighting the potential of ≤10-day courses, as effective treatment options.


Assuntos
Antibacterianos , Doença de Lyme , Doença de Lyme/tratamento farmacológico , Humanos , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Resultado do Tratamento , Duração da Terapia
2.
Funct Plant Biol ; 50(6): 455-469, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37081720

RESUMO

Heatwaves are increasingly occurring out-of-season, which may affect plants not primed for the event. Further, heat stress often coincides with water and/or nutrient stress, impairing short-term physiological function and potentially causing downstream effects on reproductive fitness. We investigated the response of water-stressed arid-zone Solanum oligacanthum and Solanum orbiculatum to spring vs summer heat stress under differing nutrient conditions. Heat stress events were imposed in open-topped chambers under in situ desert conditions. To assess short-term impacts, we measured leaf photosystem responses (F v /F m ) and membrane stability; long-term effects were compared via biomass allocation, visible damage, flowering and fruiting. Plants generally fared more poorly following summer than spring heat stress, with the exception of F v /F m . Summer heat stress caused greater membrane damage, reduced growth and survival compared with spring. Nutrient availability had a strong influence on downstream effects of heat stress, including species-specific outcomes for reproductive fitness. Overall, high temperatures during spring posed a lower threat to fitness than in severe arid summer conditions of high temperature and low water availability, which were more detrimental to plants in both the short and longer term. Our study highlights the importance of considering ecologically relevant, multiple-stressor events to understand different species responses to extreme heat.


Assuntos
Temperatura Alta , Plantas , Folhas de Planta , Estações do Ano , Água , Fenômenos Fisiológicos Vegetais
3.
Rev. otorrinolaringol. cir. cabeza cuello ; 83(1): 15-23, mar. 2023. tab
Artigo em Espanhol | LILACS | ID: biblio-1431948

RESUMO

Introducción: Las pruebas de patrones de frecuencia y patrones de duración son consideradas los gold standard de evaluación del ordenamiento auditivo temporal. A pesar de su amplia difusión, la extensión y duración de estas pruebas dificultan su utilización dentro de baterías de evaluación del procesamiento auditivo. Sin embargo, dadas sus características estructurales, pareciera ser posible reducirlas sin perder su precisión diagnóstica. Objetivo: Determinar las propiedades diagnósticas de versiones abreviadas de las pruebas de patrones de frecuencia y patrones de duración. Material y Método: Se realizó un estudio transversal de diseño observacional analítico. Se evaluaron 166 oídos de 88 sujetos con edades entre 18 y 33 años, los cuales fueron clasificados con normalidad o alteración del ordenamiento auditivo temporal. Se utilizaron las pruebas originales de Auditec de 30 ítems por oído como referencia y los primeros 10 ítems de cada oído como versión abreviada. Resultados: La versión abreviada de la prueba de patrones de frecuencia obtuvo una sensibilidad de un 94,33%, una especificidad del 94,29% y un área bajo la curva ROC de 0,980. La versión abreviada de la prueba de patrones de duración obtuvo una sensibilidad de un 89,58%, especificidad del 71,88% y un área bajo la curva ROC de 0,916. Ambas versiones tuvieron un índice de concordancia adecuado. Conclusiones: Las versiones abreviadas de la prueba de patrones de frecuencia y patrones de duración cuentan con excelentes propiedades diagnósticas para la evaluación del ordenamiento auditivo temporal y pueden ser utilizadas de manera intercambiable con las versiones originales.


Introduction: The frequency and duration pattern tests are considered the gold standard for assessing auditory temporal ordering. Despite their wide dissemination, the length and duration of these tests make it difficult to use them within auditory processing assessment batteries. However, given their structural characteristics, reducing them without losing their diagnostic accuracy seems possible. Aim: Determine the diagnostic properties of abbreviated versions of the Frequency Patterns and Duration Patterns tests. Material and Method: A cross-sectional study with an analytical observational design was carried out. 166 ears of 88 subjects aged between 18 and 33 years were evaluated, classified as normal or altered in temporal auditory order. The original Auditec tests of 30 items per ear were used as a reference, and the first 10 items of each ear as an abbreviated version. Results: The abbreviated version of the frequency patterns test obtained a sensitivity of 94.33%, a specificity of 94.29%, and an area under the ROC curve of 0.980. The abbreviated version of the duration pattern test obtained a sensitivity of 89.58%, a specificity of 71.88%, and an area under the ROC curve of 0.916. Both versions had an adequate concordance index. Conclusion: The abbreviated versions of the frequency patterns and duration patterns test have excellent diagnostic properties for assessing auditory temporal ordering and can be used interchangeably with the original versions.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Adulto Jovem , Percepção Auditiva/fisiologia , Transtornos da Percepção Auditiva/diagnóstico , Estudos Transversais , Curva ROC , Testes Auditivos/métodos
4.
Rev. cir. (Impr.) ; 75(1)feb. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1441453

RESUMO

La hernia incisional compleja es un desafío para el cirujano. Son ampliamente conocidos los factores que han permitido mejorar los resultados de la reparación herniaria, entre ellos el neumoperitoneo preoperatorio. Durante la insuflación preoperatoria, el aire difunde tanto en la cavidad abdominal como en el saco herniario. Sin embargo, gran porcentaje del contenido administrado, se distribuye mayormente en el saco herniario y no en la cavidad abdominal. En Latinoamérica, diversos equipos de cirujanos de pared abdominal han compartido experiencias en lo que respecta a la optimización de esta técnica como adyuvancia para el manejo de las hernias complejas. En este contexto, y para optimizar la distribución del aire insuflado hacia la cavidad abdominal, se comenzó a utilizar un dispositivo externo de compresión. Este trabajo busca estandarizar por primera vez esta técnica durante el neumoperitoneo preoperatorio buscando disminuir el volumen de aire insuflado, los días de neumoperitoneo y, por lo tanto, los días de hospitalización previo a la cirugía.


Complicated incisional hernia is challenging for surgeons. The factors that have improved the results of hernia repair are widely known, including preoperative pneumoperitoneum. During preoperative insufflation, air diffuses into both the abdominal cavity and the hernia sac. However, a large percentage of the administered content is distributed mainly in the hernia sac and not in the abdominal cavity. Latin-American teams of abdominal wall surgeons have shared experiences regarding the optimization of this technique as an adjuvant for the management of complicated hernias. In this context and to optimize the distribution of the insufflated air into the abdominal cavity, an external compression device began to be used. This article aims to standardize this technique for the first time during preoperative pneumoperitoneum. The target is to reduce the volume of air insufflated, the days of pneumoperitoneum and, therefore, the days of hospitalization prior to surgery.

5.
Rev Med Chil ; 151(4): 412-419, 2023 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-38687515

RESUMO

INTRODUCTION: The distribution of causes of hyperferritinemia in international series is heterogeneous. Also, the association between ferritin and prognosis is controversial. This study aims to describe the diagnosis associated with hyperferritinemia in a retrospective cohort at an academic healthcare network in Chile. METHODS: A retrospective review of adult patients admitted to our academic medical center from June 2014 to February 2017 with ferritin ≥3,000 ng/mL. All patients were classified into nine diagnostic categories. Then, the association between ferritin level and disease category, as well as mortality, was evaluated. RESULTS: Ninety-nine patients were identified. The mean age was 50.8 ± 19.9 years, 54.5% were men. The most frequent categories were "inflammatory and autoimmune diseases" (21.2%) and "hematological malignancies" (19.2%). The average ferritin was 10,539 ± 13,016.9 ng/mL, while the higher mean was 16,707 ng/mL in the "inflammatory and autoimmune diseases" category. There was a statistically significant association between the ferritin value and age but not between ferritin and diagnostic categories. In the group over 50, hematologic neoplasms (19%) and infections (19%) were more frequent. In those under 50, inflammatory and autoimmune diseases were more frequent (26.8%). There was no association between the ferritin level and mortality at 1, 3, and 12 months. CONCLUSIONS: The most frequent categories were "inflammatory and autoimmune diseases" and "hematological malignancies", but ferritin level was similar in both. Further research could validate a prognostic role.


Assuntos
Ferritinas , Hiperferritinemia , Humanos , Estudos Retrospectivos , Masculino , Chile/epidemiologia , Pessoa de Meia-Idade , Feminino , Adulto , Ferritinas/sangue , Idoso , Hiperferritinemia/sangue , Prognóstico , Centros Médicos Acadêmicos/estatística & dados numéricos , Doenças Autoimunes/sangue , Adulto Jovem
6.
Rev. chil. infectol ; 39(5)oct. 2022.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1431700

RESUMO

Introducción: La anisakidosis humana es una zoonosis transmitida por alimentos, causada por la ingestión de carne de pescado parasitada por nematodos anisákidos. Investigaciones sobre la presencia de anisákidos en pescados comercializados, sin cocción o congelación previa, en la región centro sur de Chile son escasas. Objetivo: Identificar nematodos anisákidos en catorce especies de peces marinos, obtenidos por pesca artesanal y comercializados en Concepción, Talcahuano y Lebu, ciudades de la Región del Bío Bío, Chile. Métodos: Entre los años 2018 y 2020, se examinó en busca de anisákidos a 334 pescados marinos frescos. Resultados: Se identificó larvas de Anisakis spp. y Pseudoterranova sp. en ejemplares de siete y cuatro especies de peces, respectivamente. La mayoría de las larvas se encontraron vivas y ubicadas a nivel visceral. Conclusión: La mayoría de las especies de peces que resultaron positivas son reconocidos hospederos intermediarios de estos parásitos. La presencia de anisákidos en la musculatura de estas especies indica que su preparación, en forma ahumada o cruda, es un riesgo para salud pública, recomendándose comprar estos productos en forma eviscerada y/o congelada, junto a promover su cocción.


Background: Human anisakidosis is a food-borne zoonosis, caused by the intake of fish meat parasitized by anisakid nematodes. Research of anisakids parasites in commercialized fish, without previous cooking or freezing, in the south central region of Chile is scarce. Aim: To identify anisakid nematodes in fourteen species of marine fish, obtained by artisanal fishing and commercialized in Concepción, Talcahuano and Lebu, cities from Bío Bío Region, Chile. Methods: During 2018 to 2020, we examinated for anisakids to 334 fresh marine fishes. Results: Larvae of Anisakis spp. and Pseudoterranova sp. were identified in specimens of seven and four fish species, respectively. Most of the larvae were found alive and located at the visceral level. Conclusion: Most of the positive fish species are recognized intermediate hosts for these parasites. The presence of anisakids in the musculatura of these species indicates that their preparation, in smoked or raw form, is a risk to public health, and it is recommended to buy these products in gutted and / or frozen form, together with promoting their cooking.

8.
Aesthetic Plast Surg ; 46(1): 258-264, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34351508

RESUMO

Liposuction remains one of the most frequently performed cosmetic surgical procedures and its popularity is increasing every year. However, since its inception, justified concerns regarding patient safety have placed limits on the volume of fat that can be aspirated, influenced by hemodynamic fluctuations and blood loss during liposuction. Tranexamic acid (TXA) is an antifibrinolytic agent that competitively inhibits the conversion of plasminogen to plasmin, thus preventing the binding and degradation of fibrin. Despite the existence of evidence of the effectiveness of TXA in orthopedic and cardiac surgeries, there is little evidence of its use in liposuction. The objective of this study was to evaluate the efficacy and safety of tranexamic acid in the control of surgical bleeding in patients undergoing liposuction, through a prospective, open, randomized and controlled clinical trial. Two groups of 25 participants each were formed to whom the application of TXA in a tumescent solution prior to liposuction or liposuction with the traditional technique was randomly assigned. The results showed a decrease in blood loss reflected by the differences in the final hematocrit values, as well as decrease in the same per aspirated volume (p = 0.003). No adverse events were found related with the TXA application and no blood transfusions were required in this group, in contrast to the control group where the need for blood transfusion was present in 20% of the intervened participants. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.


Assuntos
Lipectomia , Ácido Tranexâmico , Perda Sanguínea Cirúrgica/prevenção & controle , Humanos , Lipectomia/métodos , Estudos Prospectivos , Ácido Tranexâmico/uso terapêutico , Resultado do Tratamento
9.
Rev Med Chil ; 149(2): 171-177, 2021 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-34479260

RESUMO

BACKGROUND: The number of patients waiting for a lung transplant worldwide greatly exceeds the number of available donors. Ex vivo lung perfusion is a useful tool that allows marginal donor lungs to be evaluated and reconditioned for a successful lung transplantation. AIM: To describe the first Chilean and Latin American experience in ex vivo lung perfusion for marginal donor lungs before transplantation. MATERIAL AND METHODS: Descriptive analysis of all ex vivo lung perfusion conducted for marginal donor lungs at a private clinic, from April 2019 to October 2020. High risk donor lungs and rejected lungs from other transplantation centers were included. The "Toronto Protocol" was used for ex vivo lung perfusion. Donor lung characteristics and recipient outcomes were studied. RESULTS: During the study period, five ex vivo lung perfusions were performed. All lungs were reconditioned and transplanted. No complications were associated. There were no primary graft dysfunctions and only one chronic allograft dysfunction. There was no mortality during the first year. The median arterial oxygen partial pressure/fractional inspired oxygen ratio increased from 266 mm Hg in the donor lung to 419 after 3 hours of ex vivo lung perfusion (p = 0.043). CONCLUSIONS: ex vivo lung perfusion is a safe and useful tool that allows marginal donor lungs to be reconditioned and successfully transplanted.


Assuntos
Transplante de Pulmão , Circulação Extracorpórea , Humanos , América Latina , Pulmão/cirurgia , Perfusão , Doadores de Tecidos
10.
Rev. méd. Chile ; 149(2): 171-177, feb. 2021. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1389438

RESUMO

Background: The number of patients waiting for a lung transplant worldwide greatly exceeds the number of available donors. Ex vivo lung perfusion is a useful tool that allows marginal donor lungs to be evaluated and reconditioned for a successful lung transplantation. Aim: To describe the first Chilean and Latin American experience in ex vivo lung perfusion for marginal donor lungs before transplantation. Material and Methods: Descriptive analysis of all ex vivo lung perfusion conducted for marginal donor lungs at a private clinic, from April 2019 to October 2020. High risk donor lungs and rejected lungs from other transplantation centers were included. The "Toronto Protocol" was used for ex vivo lung perfusion. Donor lung characteristics and recipient outcomes were studied. Results: During the study period, five ex vivo lung perfusions were performed. All lungs were reconditioned and transplanted. No complications were associated. There were no primary graft dysfunctions and only one chronic allograft dysfunction. There was no mortality during the first year. The median arterial oxygen partial pressure/fractional inspired oxygen ratio increased from 266 mm Hg in the donor lung to 419 after 3 hours of ex vivo lung perfusion (p = 0.043). Conclusions: ex vivo lung perfusion is a safe and useful tool that allows marginal donor lungs to be reconditioned and successfully transplanted.


Assuntos
Humanos , Transplante de Pulmão , Perfusão , Doadores de Tecidos , Circulação Extracorpórea , América Latina , Pulmão/cirurgia
11.
Phys Rev Lett ; 125(22): 226801, 2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33315425

RESUMO

We performed x-ray magnetic circular dichroism (XMCD) measurements on heterostructures comprising topological insulators (TIs) of the (Bi,Sb)_{2}(Se,Te)_{3} family and the magnetic insulator EuS. XMCD measurements allow us to investigate element-selective magnetic proximity effects at the very TI/EuS interface. A systematic analysis reveals that there is neither significant induced magnetism within the TI nor an enhancement of the Eu magnetic moment at such interface. The induced magnetic moments in Bi, Sb, Te, and Se sites are lower than the estimated detection limit of the XMCD measurements of ∼10^{-3} µ_{B}/at.

12.
Phys Rev Lett ; 125(14): 147201, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064528

RESUMO

The resonant enhancement of mechanical and optical interaction in optomechanical cavities enables their use as extremely sensitive displacement and force detectors. In this Letter, we demonstrate a hybrid magnetometer that exploits the coupling between the resonant excitation of spin waves in a ferromagnetic insulator and the resonant excitation of the breathing mechanical modes of a glass microsphere deposited on top. The interaction is mediated by magnetostriction in the ferromagnetic material and the consequent mechanical driving of the microsphere. The magnetometer response thus relies on the spectral overlap between the ferromagnetic resonance and the mechanical modes of the sphere, leading to a peak sensitivity of 850 pT Hz^{-1/2} at 206 MHz when the overlap is maximized. By externally tuning the ferromagnetic resonance frequency with a static magnetic field, we demonstrate sensitivity values at resonance around a few nT Hz^{-1/2} up to the gigahertz range. Our results show that our hybrid system can be used to build a high-speed sensor of oscillating magnetic fields.

13.
Rev. chil. cir ; 69(1): 49-52, feb. 2017. ilus
Artigo em Espanhol | LILACS | ID: biblio-844324

RESUMO

Introducción: Chile se caracteriza por ser uno de los países con mayor prevalencia de patología biliar en el mundo. Dentro de los factores de riesgo de la patología biliar se encuentran el sexo femenino, la edad, el sobrepeso y la obesidad. Estos factores asociados a la disminución rápida de peso son característicos de los pacientes obesos sometidos a cirugía bariátrica. Se ha reportado que los pacientes sometidos a esta cirugía tienen una alta incidencia de colelitiasis a 12 meses postoperatorio. Objetivos: Determinar la prevalencia de patología biliar en pacientes obesos sometidos a cirugía bariátrica, y analizar la aparición de esta patología durante el seguimiento postoperatorio a un año. Material y método: Serie de casos retrospectiva, incluyendo 221 pacientes sometidos a cirugía bariátrica, con seguimiento a 12 meses. Se realizó revisión de registros clínicos, consignando peso y ecografía abdominal en el control al año. Resultados: Un 18,09% de los pacientes tenía antecedentes de colecistectomía previa. Un 13,57% de los pacientes presentaba colelitiasis en el preoperatorio y se realizó colecistectomía de forma concomitante en todos ellos. Se realizó seguimiento a un año en 151 pacientes. En las ecografías al año, un 3,54% presentaba colelitiasis. Conclusiones: Existe una elevada prevalencia de colelitiasis en la población sometida a cirugía bariátrica. La aparición de esta patología en el primer año fue menor a la reportada en la literatura. Se debe considerar un seguimiento cercano para la detección de esta patología durante el primer año postoperatorio.


Introduction: Chile is known for being one of the countries with higher prevalence of gallstone disease in the world. Among the risk factors for biliary pathology are female gender, age, overweight and obesity. These factors associated with rapid weight loss are characteristic of obese patients undergoing bariatric surgery. It has been reported that patients undergoing these surgeries have a high incidence of cholelithiasis to 12 months postoperatively. Objectives: To determine the prevalence of gallstone disease in obese patients undergoing bariatric surgery, and analyze the occurrence of this disease during the postoperative follow-up up to 12 months. Material and methods: Retrospective case series including 221 patients undergoing bariatric surgery, with follow-up up to 12 months. Review of clinical records and abdominal ultrasound was conducted. Results: A 18.09% of patients had a history of previous cholecystectomy. A 13.57% of patients had preoperative cholelithiasis and a concomitant cholecystectomy was performed in all of them. Follow up was conducted in 151 patients. In ultrasound examinations at one year, 3.54% had cholelithiasis. Conclusions: There is a high prevalence of cholelithiasis in the population undergoing bariatric surgery. The emergence of this disease in the first year was lower than that reported in the literature. Patients should be closely monitored for the detection of this disease during the first postoperative year.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Cirurgia Bariátrica/métodos , Colecistectomia/métodos , Colelitíase/epidemiologia , Colelitíase/cirurgia , Obesidade/cirurgia , Colelitíase/complicações , Colelitíase/diagnóstico por imagem , Obesidade/complicações , Cuidados Pré-Operatórios , Prevalência , Estudos Retrospectivos
14.
J Oral Rehabil ; 44(2): 125-132, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27893167

RESUMO

To investigate low-level laser therapy (LLLT) applied to treat burning mouth syndrome (BMS). This prospective, comparative, partially blinded, single-centre, clinical trial of GaAlAs Laser, with 815 nm wavelength, included 44 BMS patients divided randomly into three groups: Group I (n = 16): GaAlAs laser 815 nm wavelength, 1 W output power, continuous emissions, 4 s, 4 J and fluence rate 133·3 J cm-2 ; Group II (n = 16): GaAlAs infrared laser, 815 nm wavelength, 1 W output power, continuous emissions, 6 s, 6 J and fluence rate 200 J cm-2 ; Group III (n = 12) placebo group, sham laser. All groups received a weekly dose for 4 weeks. Pain intensity was recorded using a 10-cm visual analogue scale; patients responded to the oral health impact profile (OHIP-14), xerostomia severity test and the hospital anxiety-depression scale (HAD). These assessments were performed at baseline, 2 and 4 weeks. LLLT decreased pain intensity and improved OHIP-14 scores significantly from baseline to 2 weeks in groups I and II compared with the placebo group. No statistically significant differences were found from 2 to 4 weeks. Overall improvements in visual analogue scale (VAS) scores from baseline to the end of treatment were as follows: Group I 15·7%; Group II 15·6%; Group III placebo 7·3%. LLLT application reduces symptoms slightly in BMS patients.


Assuntos
Síndrome da Ardência Bucal/radioterapia , Lasers Semicondutores/uso terapêutico , Terapia com Luz de Baixa Intensidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Síndrome da Ardência Bucal/terapia , Feminino , Humanos , Terapia com Luz de Baixa Intensidade/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doses de Radiação , Espanha , Resultado do Tratamento , Escala Visual Analógica , Xerostomia
15.
Phys Rev Lett ; 117(17): 176602, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27824472

RESUMO

Recent experiments reporting an unexpectedly large spin Hall effect (SHE) in graphene decorated with adatoms have raised a fierce controversy. We apply numerically exact Kubo and Landauer-Büttiker formulas to realistic models of gold-decorated disordered graphene (including adatom clustering) to obtain the spin Hall conductivity and spin Hall angle, as well as the nonlocal resistance as a quantity accessible to experiments. Large spin Hall angles of ∼0.1 are obtained at zero temperature, but their dependence on adatom clustering differs from the predictions of semiclassical transport theories. Furthermore, we find multiple background contributions to the nonlocal resistance, some of which are unrelated to the SHE or any other spin-dependent origin, as well as a strong suppression of the SHE at room temperature. This motivates us to design a multiterminal graphene geometry which suppresses these background contributions and could, therefore, quantify the upper limit for spin-current generation in two-dimensional materials.

16.
Opt Express ; 24(2): A154-67, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-26832569

RESUMO

In this work, we present a study of the nonlinear absorption properties from different gold nanorod (NR) systems in aqueous suspension. The NRs were obtained with the bottom-up protocol by the seed-mediated growth method (SMG), using Ag(+) ions at different concentrations, and CTAB as surfactant. By using this method, aspect ratios between 2 and 5 were obtained. The transverse surface plasmons (TSP) are located between 514 - 535 nm, while the longitudinal surface plasmons (LSP) are between 639 - 921 nm, for the different samples studied. The Z-scan technique was implemented for open (OA) and closed (CA) aperture at 532 and 1064 nm, with laser pulses of 26 ps, for vertical and horizontal polarizations, with respect to the incidence plane (horizontal). At 532 nm all samples showed saturable absorption (SA), while for samples with LSP near 1064 nm, such effect was observed only at low-energy pulse experimental conditions. In the high-energy pulse regime, an apparent reverse-saturable absorption (RSA) was observed for both wavelengths. However for 532 nm, it was possible to determine that this effect results from structural changes in the samples, which are manifested through the behavior of nonlinear absorption and refraction curves. These results were used to determine the irradiances to which NRs can be modified by photodegradation.

18.
Enferm. univ ; 12(4): 226-234, oct.-dic. 2015. tab
Artigo em Espanhol | LILACS, BDENF - Enfermagem | ID: lil-785660

RESUMO

Posterior al nacimiento el recién nacido cursa por un periodo de transición para ajustarse a los cambios fisiológicos que implican el estar fuera del vientre materno. Durante este periodo es común la aparición de complicaciones como la ictericia neonatal, padecimiento común a nivel mundial, que se define como la coloración amarilla de la piel resultado de los altos niveles circulantes de bilirrubina. Representa una de las principales causas de morbilidad, tanto en recién nacidos de término como en pretérmino. Su etiología se encuentra relacionada con distintos factores de riesgo maternos y/o neonatales y, aunque sus índices de mortalidad son bajos, el retraso en su diagnóstico y tratamiento conlleva severas complicaciones, como el kernicterus . Dentro de los factores de riesgo maternos la hiperbilirrubinemia por incompatibilidad sanguínea entre la madre y el recién nacido, como en el presente caso, requiere de la inmediata y oportuna atención del profesional de enfermería que labora dentro de los servicios de cuidados neonatales, con el objetivo de limitar el daño, favorecer la pronta recuperación, la reunión del binomio y la posterior integración del recién nacido a la dinámica familiar. El presente estudio de caso fue elaborado bajo el marco conceptual del modelo de adaptación de Roy, y a través del proceso enfermero, como herramienta metodológica para priorizar el cuidado. Aunque no fue posible documentar una disminución considerable en los niveles de bilirrubina, los resultados obtenidos se consideraron satisfactorios, ya que se logró mejorar el nivel de adaptación del recién nacido en el modo adaptativo fisiológico.


After being born, the baby goes through a period of transition of physiological changes and adjustments. During this period, the newly born can experience neonatal jaundice, an imbalance characterized by the yellow pigmentation of the skin as the result of the high levels of circulating bilirubin. This problem is one of the main causes of both on-term and pre-term neonatal mortality. There are different maternal and neonatal risk factors involved in the issue and, although its mortality rates are low, a delay in diagnosing and treating neonatal jaundice leads to severe complications such as kernicterus. A hyperbilirubinemia due to blood incompatibility between the mother and the baby, like in this particular case, requires immediate attention from the neonatal-care nursing professional in order to limit the damage, and to favor a prompt recovery, the reunion of the mother and her baby, and the integration of the baby into other family dynamics. This study was conducted within the conceptual frame of the Roy's Adaptation Model and through the nursing process. Although, a considerable decrease in the bilirubin level was not achieved, the obtained results were considered satisfactory since the level of physiological adaptation of the newborn improved significantly.


Posterior ao nascimento, o recém-nascido mantém um período de transição para se ajustar aos câmbios fisiológicos que implicam estar fora do ventre materno. Durante este período, é comum a aparição de complicações como a icterícia neonatal, padecimento comum a nível mundial, que se define como a coloração amarela da pele, resultado dos altos níveis circulantes de bilirrubina. Representa uma das principais causas de morbidade tanto em recém-nascidos de término e pré-término. A sua etiologia encontra-se relacionada a distintos fatores de risco maternos e/ou neonatais e, ainda que seus índices de morbidade seja baixos, o retraso no seu diagnóstico e tratamento envolve severas complicações, como o kernicterus. Dentro dos fatores de risco maternos, a hiperbilirrubina por incompatibilidade sanguínea entre a mãe e o recém-nascido, como no presente caso, requer da imediata e oportuna atenção do profissional de enfermagem que trabalha dentro dos serviços de cuidados neonatais, com o objetivo de limitar o dano, favorecendo a rápida recuperação, a reunião do binômio e a posterior integração do recém-nascido à dinâmica familiar. O presente estudo de caso foi elaborado sob o marco conceitual do Modelo de Adaptação de Roy e através do Processo Enfermeiro, como ferramenta metodológica para priorizar o cuidado. Ainda que não foi possível documentar uma diminuição considerável nos níveis de bilirrubina, os resultados obtidos consideraram-se satisfatórios, já que conseguiu melhorar o nível de adaptação do recém-nascido no modo adaptativo fisiológico.


Assuntos
Humanos , Masculino , Recém-Nascido , Hiperbilirrubinemia Neonatal
20.
Rev. chil. enferm. respir ; 31(1): 39-47, mar. 2015. tab
Artigo em Espanhol | LILACS | ID: lil-747512

RESUMO

Work related diseases and common diseases are covered by separated health systems in Chile. Chilean Ministry of Health focuses on common diseases, making work related diseases almost absent from public health policies. In this article current national and international information about the magnitude and impact of silicosis is reviewed. Although the quality of the national information is suboptimal, it is possible to estimate in several hundreds of thousands the number of workers exposed to silica dust, tens of thousands those under medical surveillance and thousands those currently affected by the disease. Albeit, additional efforts need to be made to estimate the burden of this disease on the Chilean population, information gathered in this article suggests that it is a relevant public health issue, deserving more importance among public policies in our country.


Las enfermedades comunes y laborales son atendidas en distintos sistemas de aseguramiento de la salud en Chile. Las políticas públicas emanadas del Ministerio de Salud se enfocan en las enfermedades comunes, relegando a un rol secundario a aquellas ocasionadas por la actividad laboral de las personas. En este artículo, los autores revisan información actualizada tanto nacional como internacional con el fin de determinar si la silicosis constituye un problema de salud relevante. Aunque la calidad de la información nacional no es óptima, su revisión permite estimar que son cientos de miles los trabajadores expuestos a sílice cristalina, que hay varias decenas de miles bajo vigilancia médica y que son más de mil los portadores de la enfermedad. Si bien es necesario hacer mayores esfuerzos para estimar la carga que esta patología representa para la sociedad chilena, la información recopilada indica que constituye un problema de salud pública relevante que debiera tener mayor protagonismo en las políticas públicas de nuestro país.


Assuntos
Humanos , Silicose/etiologia , Silicose/epidemiologia , Exposição Ocupacional , Doenças Profissionais , Chile/epidemiologia , Saúde Pública , Fatores de Risco , Doença Pulmonar Obstrutiva Crônica/patologia , Programas Nacionais de Saúde
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...