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1.
Oncol Lett ; 27(4): 177, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38464335

RESUMEN

Adrenal cortical eosinophilic adenoma usually presents as non-functional adrenal tumor but may lead to Cushing's syndrome in patients. The present article reports a patient with Cushing's syndrome caused by right adrenocortical oncocytoma. The patient was treated in Urology Department of Wuchuan People's Hospital (Zunyi, China) in November 2022 because of hirsutism, weight gain and hypertension. A laparoscopic right adrenal tumor resection was performed using an abdominal approach. Following surgery, blood pressure and heart rate of the patient fluctuated within a healthy range and menstruation returned to normal. Laparoscopic adrenalectomy has obvious advantages over open adrenalectomy, such as less trauma, shorter recovery time and fewer complications. Thus, this treatment for this rare disease is safe and feasible.

2.
ACS Appl Mater Interfaces ; 15(4): 5521-5528, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36651188

RESUMEN

Contact resistance and charge trapping are two key obstacles, often intertwined, that negatively impact on the performance of organic field-effect transistors (OFETs) by reducing the overall device mobility and provoking a nonideal behavior. Here, we expose organic semiconductor (OSC) thin films based on blends of 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT-C8) with polystyrene (PS) to (i) a CH3CN vapor annealing process, (ii) a doping I2/water procedure, and (iii) vapors of I2/CH3CN to simultaneously dope and anneal the films. After careful analysis of the OFET electrical characteristics and by performing local Kelvin probe force microscopy studies, we found that the vapor annealing process predominantly reduces interfacial shallow traps, while the chemical doping of the OSC film is responsible for the diminishment of deeper traps and promoting a significant reduction of the contact resistance. Remarkably, the devices treated with I2/CH3CN reveal ideal electrical characteristics with a low level of shallow/deep traps and a very high and almost gate-independent mobility. Hence, this work demonstrates the promising synergistic effects of performing simultaneously a solvent vapor annealing and doping procedure, which can lead to trap-free OSC films with negligible contact resistance problems.

3.
Nanoscale ; 15(1): 230-236, 2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36472089

RESUMEN

The deposition of organic semiconductors (OSCs) using solution shearing deposition techniques is highly appealing for device implementation. However, when using high deposition speeds, it is necessary to use very concentrated OSC solutions. The OSCs based on the family of dinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (DNTT) have been shown to be excellent OSCs due to their high mobility and stability. However, their limited solubility hinders the processing of these materials at high speed. Here, we report the conditions to process alkylated DNTT and the S-shaped π-core derivative S-DNTT by bar-assisted meniscus shearing (BAMS) at high speed (i.e., 10 mm s-1). In all the cases, homogeneous thin films were successfully prepared, although we found that the gain in solubility achieved with the S-DNTT derivative strongly facilitated solution processing, achieving a field-effect mobility of 2.1 cm2 V-1 s-1, which is two orders of magnitude higher than the mobility found for the less soluble linear derivatives.

4.
ACS Appl Electron Mater ; 4(5): 2432-2441, 2022 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-35647553

RESUMEN

Composites exhibit unique synergistic properties emerging when components with different properties are combined. The tuning of the energy bandgap in the electronic structure of the material allows designing tailor-made systems with desirable mechanical, electrical, optical, and/or thermal properties. Here, we study an emergent insulator-metal transition at room temperature in bilayered (BL) thin-films comprised of polycarbonate/molecular-metal composites. Temperature-dependent resistance measurements allow monitoring of the electrical bandgap, which is in agreement with the optical bandgap extracted by optical absorption spectroscopy. The semiconductor-like properties of BL films, made with bis(ethylenedithio)-tetrathiafulvalene (BEDT-TTF or ET) α-ET2I3 (nano)microcrystals as two-dimensional molecular conductor on one side and insulator polycarbonate as a second ingredient, are attributed to an emergent phenomenon equivalent to the transition from an insulator to a metal. This made it possible to obtain semiconducting BL films with tunable electrical/optical bandgaps ranging from 0 to 2.9 eV. A remarkable aspect is the similarity close to room temperature of the thermal and mechanical properties of both composite components, making these materials ideal candidates to fabricate flexible and soft sensors for stress, pressure, and temperature aiming at applications in wearable human health care and bioelectronics.

5.
Annu Rev Chem Biomol Eng ; 13: 431-455, 2022 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-35378042

RESUMEN

This review discusses the complex behaviors in diverse chemical and biochemical systems to elucidate their commonalities and thus help develop a mesoscience methodology to address the complexities in even broader topics. This could possibly build a new scientific paradigm for different disciplines and could meanwhile provide effective tools to tackle the big challenges in various fields, thus paving a path toward combining the paradigm shift in science with the breakthrough in technique developments. Starting with our relatively fruitful understanding of chemical systems, the discussion focuses on the relatively pristine but very intriguing biochemical systems. It is recognized that diverse complexities are multilevel in nature, with each level being multiscale and the complexity emerging always at mesoscales in mesoregimes. Relevant advances in theoretical understandings and mathematical tools are summarized as well based on case studies, and the convergence between physics and mathematics is highlighted.

6.
ACS Appl Mater Interfaces ; 12(25): 28416-28425, 2020 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-32460481

RESUMEN

The present work assesses improved carrier injection in organic field-effect transistors by contact doping and provides fundamental insight into the multiple impacts that the dopant/semiconductor interface details have on the long-term and thermal stability of devices. We investigate donor [1]benzothieno[3,2-b]-[1]benzothiophene (BTBT) derivatives with one and two octyl side chains attached to the core, therefore constituting asymmetric (BTBT-C8) and symmetric (C8-BTBT-C8) molecules, respectively. Our results reveal that films formed out of the asymmetric BTBT-C8 expose the same alkyl-terminated surface as the C8-BTBT-C8 films do. In both cases, the consequence of depositing fluorinated fullerene (C60F48) as a molecular p-dopant is the formation of C60F48 crystalline islands decorating the step edges of the underlying semiconductor film surface. We demonstrate that local work function changes along with a peculiar nanomorphology lead to the double beneficial effect of lowering the contact resistance and providing long-term and enhanced thermal stability of the devices.

7.
Vaccines (Basel) ; 8(2)2020 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-32466622

RESUMEN

Vaccines against Porcine circovirus type 2 (PCV2) have been studied intensely and found to be effective in decreasing mortality and improving growth in swine populations. In this study, interleukin-23 (IL-23) gene was cloned from peripheral blood mononuclear cells (PBMCs) of Tibetan pigs and inserted into a eukaryotic VR1020 expression vector-VRIL23. Coated with chitosan (CS), the VRIL23-CS was intramuscularly injected into 3-week-old piglets with PCV2 vaccine. The blood was collected after vaccination at 0, 1, 2, 4, 8, and 12 weeks, respectively, to detect the immunological changes. The IgG2a and specific PCV2 antibodies were detected using ELISA, and blood CD4+ and CD8+ T cells were quantified by flow cytometry. Quantitative fluorescence PCR was used to evaluate the expression of immune genes. The results indicate that leukocytes, erythrocytes, and CD4+ and CD8+ T cells increased significantly in the blood of VRIL23-CS inoculated piglets in comparison with the control (p < 0.05) and so did the IgG2a and PCV2 antibodies. In addition, the expressions of Toll-like receptor (TLR) 2, TLR7, cluster of differentiation (CD) 45, IL-15, IL-12, signal transducer and activator of transcription (STAT)1, STAT2, STAT3, STAT4, and B-cell lymphoma (Bcl)-2 genes were also obviously higher in the VRIL23-CS inoculated pigs at different time points (p < 0.05). Overall, the results demonstrated that VRIL23-CS can enhance the comprehensive immune responses to PCV2 vaccine in vivo and has the promising potential to be developed into a safe and effective adjuvant to promote the immunity of pig against PCV disease.

9.
Natl Sci Rev ; 6(6): 1091-1093, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34691982
10.
Annu Rev Chem Biomol Eng ; 9: 41-60, 2018 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-29553825

RESUMEN

This review covers three decades of research on mesoscale phenomena in chemical engineering, from the energy minimization multiscale (EMMS) model specific for gas-solid fluidization to a general principle of compromise in competition between dominant mechanisms, leading to the proposed concept of mesoscience. First, the concept of mesoscales is reviewed with respect to their commonality, diversity, and misunderstanding in different fields. Then, the evolution from the EMMS model to the EMMS principle common to all mesoscales is described to show the rationale of mesoscience referring to both mesoscales and mesoregimes. Finally, the potential universality of mesoscience and its importance, particularly to enable virtual process engineering (VPE) by realizing the consistency of logic and structure between the problem, the model, the software, and the computer, are discussed. The review concludes by illustrating possible case studies to collect more evidence and a potential framework for mesoscience.


Asunto(s)
Modelos Teóricos , Ingeniería Química , Gases/química , Programas Informáticos , Termodinámica
11.
Res Vet Sci ; 117: 224-232, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29306151

RESUMEN

In order to develop a novel effective immunomodulator to enhance pig resistance against post-weaning multi systemic wasting syndrome (PMWS), a recombinant plasmid co-expressing pig interleukin-2 (IL-2) and fusion interleukin-4/6 (IL-4/6) genes, designated VRIL4/6-2, was constructed and encapsulated in chitosan (CS) nanoparticles prepared by the ionotropic gelation method. Then 21-day old piglets were divided into two groups and intramuscularly injected respectively with VPIL4/6-2-CS and saline along with the porcine circovirus-2 (PCV-2) vaccine. The blood was collected from each piglet on days 0, 7, 14, 28, 56 and 84 after vaccination to assay the immunological changes. Content of IgG2a, CD4+, CD8+ T cells increased significantly in the sera or blood of piglets treated with VPIL4/6-2-CS (P<0.05). Furthermore, the expression level of IL-2, IL-4, IL-6, IL-15, TLR-2, TLR-7, Bcl-2, TNF-α, CD45 and STATs (STAT1, STAT2, STAT3, STAT4) genes were significantly elevated in the treated piglets respectively in different days after inoculation (P<0.05). The growth weight gain of the treated piglets was markedly improved in comparison with the controls (P<0.05). These indicate that VPIL-4/6-2 entrapped with chitosan nanoparticles is a safe and promising effective adjuvant to promote the immune response of pig to PCV-2 vaccination.


Asunto(s)
Circovirus/inmunología , Interleucina-2/inmunología , Síndrome Multisistémico de Emaciación Posdestete Porcino/prevención & control , Porcinos/inmunología , Animales , Quitosano , Interleucina-2/administración & dosificación , Interleucina-2/genética , Interleucina-4/administración & dosificación , Interleucina-4/genética , Interleucina-4/inmunología , Interleucina-6/administración & dosificación , Interleucina-6/genética , Interleucina-6/inmunología , Nanopartículas , Vacunas , Vacunas de ADN/inmunología
12.
Langmuir ; 33(42): 11582-11589, 2017 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-28732446

RESUMEN

This article explores the adsorbate distributions in the adlayer for a model A-B2 system of heterogeneous catalysis, i.e., A + 1/2B2 → AB, via kinetic Monte Carlo (KMC) simulations. In comparison with our previous work on the A-B model (Sun, F.; Huang, W.; Li, J. Structural characteristics of the adlayer in heterogeneous catalysis. Chem. Eng. Sci. 2016, 153, 87-92), species B2 here brings about significant new features due to its special site requirement during adsorption and desorption and a different stoichiometric ratio in reactions. The effects of various kinetic processes on the adsorbate distribution are found to be similar to those in the A-B system; that is, both desorption and diffusion (besides adsorption) processes contribute to the adlayer uniformity while reactions account for clustering. However, desorption exhibits a stronger role than diffusion in homogenizing the adlayer, which is opposite to the finding in the previous A-B model. Under a fixed partial pressure, different reaction and desorption rate constants can lead to steady states with different dominant species, which has not been observed in the A-B system. The regime of species B poisoning shrinks as well, leading to the spreading of the coexisting regime, in comparison with the A-B model.

13.
Adv Mater ; 29(1)2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27786378

RESUMEN

Compositional modification and surface treatments of a TiO2 film prepared by a low-temperature route are carried out by a new promising method. Inverted polymer solar cells incorporating the post-treated TiO2 :TOPD electron-transport layer achieve the highest efficiency of 10.5%, and more importantly, eliminate the light-soaking problem that is commonly observed in metal-oxide-based inverted polymer solar cells.

14.
J Mol Graph Model ; 68: 114-127, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27423742

RESUMEN

The C-terminal domain of measles virus nucleoprotein is an intrinsically disordered protein that could bind to the X domain (XD) of phosphoprotein P to exert its physiological function. Experiments reveal that the minimal binding unit is a 21-residue α-helical molecular recognition element (α-MoRE-MeV), which adopts a fully helical conformation upon binding to XD. Due to currently limited computing power, direct simulation of this coupled folding and binding process with atomic force field in explicit solvent cannot be achieved. In this work, two advanced sampling methods, metadynamics and parallel tempering, are combined to characterize the free energy surface of this process and investigate the underlying mechanism. Starting from an unbound and partially folded state of α-MoRE-MeV, multiple folding and binding events are observed during the simulation and the energy landscape was well estimated. The results demonstrate that the isolated α-MoRE-MeV resembles a molten globule and rapidly interconverts between random coil and multiple partially helical states in solution. The coupled folding and binding process occurs through the induced fit mechanism, with the residual helical conformations providing the initial binding sites. Upon binding, α-MoRE-MeV can easily fold into helical conformation without obvious energy barriers. Two mechanisms, namely, the system tending to adopt the structure in which the free energy of isolated α-MoRE-MeV is the minimum, and the binding energy of α-MoRE-MeV to its partner protein XD tending to the minimum, jointly dominate the coupled folding and binding process. With the advanced sampling approach, more IDP systems could be simulated and common mechanisms concerning the coupled folding and binding process could be investigated in the future.


Asunto(s)
Simulación por Computador , Proteínas Intrínsecamente Desordenadas/química , Nucleoproteínas/química , Solventes/química , Proteínas Virales/química , Modelos Moleculares , Proteínas de la Nucleocápside , Fosfoproteínas/química , Unión Proteica , Conformación Proteica , Dominios Proteicos , Termodinámica
15.
Biophys Chem ; 209: 9-20, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26656380

RESUMEN

Binding of glycoprotein Ibα to von Willebrand factor induces platelet adhesion to injured vessel walls and initiates a multistep hemostatic process. It has been hypothesized that the flow condition could induce a loop to ß-sheet conformational change in the ß-switch region of glycoprotein Ibα, which regulates it binding to the von Willebrand factor and facilitates the blood clot formation and wound healing. In this work, direct molecular dynamics (MD), flow MD and metadynamics, were employed to investigate the mechanisms of this flow induced conformational transition process. Specifically, the free energy landscape of the whole transition process was drawn by metadynamics with the path collective variable approach. The results reveal that without flow, the free energy landscape has two main basins, including a random loop basin stabilized by large conformational entropy and a partially folded ß-sheet basin. The free energy barrier separating these two basins is relatively high and the ß-switch could not fold from loop to ß-sheet state spontaneously. The fully ß-sheet conformations located in high free energy regions, which are also unstable and gradually unfold into partially folded ß-sheet state with flow. Relatively weak flow could trigger some folding of the ß-switch but could not fold it into fully ß-sheet state. Under strong flow conditions, the ß-switch could readily overcome the high free energy barrier and fold into fully ß-sheet state.


Asunto(s)
Complejo GPIb-IX de Glicoproteína Plaquetaria/química , Conformación Proteica
16.
BMC Ophthalmol ; 15: 76, 2015 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-26187041

RESUMEN

BACKGROUND: Hsf4 is closely related to the development of cataract. However, the molecular mechanisms remain unknown. This study aimed to explore the molecular mechanisms that how Hsf4 mutations influence development of lens and thus lead to cataract in mouse. METHODS: The mRNA expression profile of mouse tissue samples from Hsf4-null and wile-type lenses was downloaded from Gene Expression Omnibus database. Then the LIMMA package was used to screen differentially expressed genes (DEGs) and DAVID was applied to identify the significantly enriched Gene Ontology (GO) categories for DEGs. Furthermore, the protein-protein interaction (PPI) network of DEGs was constructed using Cytoscape and the key modules were selected from the PPI network based on the MCODE analysis. RESULTS: A total of 216 DEGs were screened, including 51 up- and 165 down-regulated genes. Meanwhile, nine GO terms were obtained, and DEGs such as SGK1, CRY2 and REV1 were enriched in response to DNA damage stimulus. Furthermore, 89 DEGs and 99 gene pairs were mapped into the PPI network and Ubc was the hob node. Two key modules, which contained the genes (e.g. Ubc, Egr1, Ptgs2, Hmox1, Cd44, Btg2, Cyr61 and Fos) were related to response to DNA damage stimulus. CONCLUSIONS: The deletion of Hsf4 affects the expression of many genes, such as Ubc, Ptgs2, Egr1 and Fos. These genes may be involved in the development of cataract and could be used as therapeutic targets for cataract.


Asunto(s)
Catarata/genética , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica/fisiología , ARN Mensajero/genética , Factores de Transcripción/genética , Animales , Perfilación de la Expresión Génica , Factores de Transcripción del Choque Térmico , Cristalino/metabolismo , Ratones , Análisis por Micromatrices , Reacción en Cadena de la Polimerasa
17.
J Biomol Struct Dyn ; 31(7): 779-87, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22908945

RESUMEN

A multiscale simulation method of protein folding is proposed, using atomic representation of protein and solvent, combing genetic algorithms to determine the key protein structures from a global view, with molecular dynamic simulations to reveal the local folding pathways, thus providing an integrated landscape of protein folding. The method is found to be superior to previously investigated global search algorithms or dynamic simulations alone. For secondary structure formation of a selected peptide, RN24, the structures and dynamics produced by this method agree well with corresponding experimental results. Three most populated conformations are observed, including hairpin, ß-sheet and α-helix. The energetic barriers separating these three structures are comparable to the kinetic energy of the atoms of the peptide, implying that the transition between these states can be easily triggered by kinetic perturbations, mainly through electrostatic interactions between charged atoms. Transitions between α-helix and ß-sheet should jump over at least two energy barriers and may stay in the energetic trap of hairpin. It is proposed that the structure of proteins should be jointly governed by thermodynamic and dynamic factors; free energy is not the exclusive dominant for stability of proteins.


Asunto(s)
Pliegue de Proteína , Estructura Secundaria de Proteína , Proteínas/química , Algoritmos , Cinética , Modelos Moleculares , Simulación de Dinámica Molecular , Termodinámica
18.
PLoS One ; 7(6): e38861, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22719968

RESUMEN

OBJECTIVE: To investigate quality of life (QOL) and related characteristics among an urban neo-poverty population in northeast China, and to compare this population with a traditional poverty cohort. DESIGN: The research was a cross-sectional survey executed from June 2005 to October 2007, with a sample of 2940 individuals ages 36 to 55 in three different industrial cities of northeast China. Data were collected on QOL status and sociodemographic characteristics. QOL was assessed using the 36-item Short Form Health Survey (Chinese version). Multiple regression analysis was employed to analyze association between sociodemographic variables and QOL. RESULTS: The scores for QOL in the neo-poverty group were higher than those in the traditional poverty group, but lower than those in the general population. When the neo-poverty population was divided into two subgroups by age, 36-45 years and 46-55 years, the differences in QOL scores were not significant. However, there were significant differences in several dimensions between two subgroups according to unemployment time (<5 years and >5 years). Additionally, stepwise regression analysis indicated that disease burden, including disease and medical expenditures, was a common risk factor for declining QOL in the neo-poverty group. CONCLUSIONS: Despite some limitations, this study provides initial evidence that the QOL of the urban neo-poverty population lies between that of the general population and traditional poverty. QOL of the neo-poverty group approached QOL of the traditional poverty group with increased unemployment years. In addition to decreased income, disease burden is the most important factor influencing QOL status in urban neo-poverty.


Asunto(s)
Pobreza , Calidad de Vida , Población Urbana , Adulto , China , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad
19.
Graefes Arch Clin Exp Ophthalmol ; 249(6): 871-7, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21240521

RESUMEN

OBJECTIVE: To investigate the influence of Estradial (E(2)) at physiological concentration on mRNA expression of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1α(HIF-α1) in bovine retinal vascular endothelial cells (BRECs) under different oxygen conditions. METHODS: The mRNA expression of VEGF, HIF-1α in BRECs was studied by quantitative reverse-transcription PCR (qRT-PCR), and protein levels were assayed by Western Blot. Different concentrations of E(2) (10(-12), 10(-10), 10(-8) mol/l) and estrogen receptor antagonist Tamoxifen (10(-7) mol/l) were added into the cell culture medium of different groups, while the phosphate-buffered saline (PBS) was added in the control group instead. Culture conditions were set to be under normoxia and hypoxia. The results of each group were detected after 8 hours and 24 hours. RESULTS: (1) Under hypoxia, gene expression of VEGF, HIF-1α in BRECs increased more than that of the control group (P < 0.05). There is evident positive correlation between the mRNA and protein levels of VEGF and HIF-1α (r = 0.82). (2) Treated with 10(-8) mol/l E(2,) the expression of VEGF mRNA was increased in a time-dependent manner (P < 0.05). Treated with the indicated to concentrations of E(2) (10(-12 ∼ -8) mol/l) under normoxia for twenty-four hours, the mRNA expression of VEGF in BRECs was increased in a dose-dependent manner (P < 0.05), whereas E(2) did not influence the mRNA expression of HIF-1α (P > 0.05). (3) Under hypoxia , E(2) reduced the mRNA and protein levels of HIF-1α and VEGF in a concentration-dependent manner (P < 0.05), and the decrease developed in a time-dependent manner (P < 0.05). (4) An overdose of tamoxifen (10(-7) mol/l) reversed the effect of E(2) (10(-8) mol/l) (P < 0.05). CONCLUSIONS: E(2) increases the gene expression of VEGF in BRECs under normoxia, whereas E(2) reduces the gene expression of VEGF in BRECs through HIF-1α under hypoxic conditions in a dose-dependent and time-dependent manner. The contrasting effect of E(2) on mRNA expression of VEGF may play a prophylactic role in retinopathy of prematurity (ROP).


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Estradiol/farmacología , Regulación de la Expresión Génica/fisiología , Hipoxia/metabolismo , ARN Mensajero/metabolismo , Vasos Retinianos/citología , Factor A de Crecimiento Endotelial Vascular/genética , Animales , Western Blotting , Bovinos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Endotelio Vascular/metabolismo , Antagonistas de Estrógenos/farmacología , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Oxígeno/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tamoxifeno/farmacología , Factores de Tiempo
20.
Biomed Environ Sci ; 23(3): 234-43, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20708504

RESUMEN

OBJECTIVE: Solar ultraviolet (UV) radiation is an important environmental factor that affects human health. The understanding of diurnal variations of UV radiation at anatomical sites may be helpful in developing ways to protect humans from the harmful effects of UV radiation. METHODS: In order to characterize the diurnal variations, the UV exposure values were measured at 30 min intervals by using Solar-UV Sensors and a rotating manikin in Shenyang city of China (41 degrees 51'N, 123 degrees 27'E). Measurement data for four representative days (in each of the four seasons respectively) were analyzed. RESULTS: The diurnal variations in solar UV radiation at the shoulder, the forehead and the chest were similar to those associated with a horizontal control measurement. However, the diurnal variations at the eye and the cheek exhibited bimodal distributions with two peaks in spring, summer and autumn, and a unimodal distribution in winter. The UV exposure peaks at the eye and the cheek were measured at solar elevation angles (SEA) of about 30 degrees and 40 degrees , respectively. CONCLUSION: The protection of some anatomical sites such as the eye from high UV exposure should not be focused solely on the periods before and after noon, especially in the places and seasons with high SEA.


Asunto(s)
Ritmo Circadiano , Rayos Ultravioleta
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