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1.
Plant Cell ; 29(10): 2644-2660, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28899981

RESUMEN

Ribosome-related mutants in Arabidopsis thaliana share several notable characteristics regarding growth and development, which implies the existence of a common pathway that responds to disorders in ribosome biogenesis. As a first step to explore this pathway genetically, we screened a mutagenized population of root initiation defective2 (rid2), a temperature-sensitive mutant that is impaired in pre-rRNA processing, and isolated suppressor of root initiation defective two1 (sriw1), a suppressor mutant in which the defects of cell proliferation observed in rid2 at the restrictive temperature was markedly rescued. sriw1 was identified as a missense mutation of the NAC transcription factor gene ANAC082 The sriw1 mutation greatly alleviated the developmental abnormalities of rid2 and four other tested ribosome-related mutants, including rid3 However, the impaired pre-rRNA processing in rid2 and rid3 was not relieved by sriw1 Expression of ANAC082 was localized to regions where phenotypic effects of ribosome-related mutations are readily evident and was elevated in rid2 and rid3 compared with the wild type. These findings suggest that ANAC082 acts downstream of perturbation of biogenesis of the ribosome and may mediate a set of stress responses leading to developmental alterations and cell proliferation defects.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Procesamiento Postranscripcional del ARN/fisiología , Ribosomas/metabolismo
2.
Opt Express ; 24(5): 4411-4420, 2016 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-29092270

RESUMEN

Red, green, and blue (RGB) light-emitting diode (LED) is a narrow-band light source that can improve visual contrast, and thus, can be used for special illumination. In this study, three RGB LEDs, each provided with two reflective mirrors, are used to design an all-reflective color temperature-adjustable LED flashlight. The LED flashlight features an adjustable color temperature ranging from 2000 K to 6500 K, a uniformity of illuminance of 0.68, an average difference of uniformity of approximately 25%, and a color uniformity of 0.0042.

3.
Physiol Plant ; 153(1): 137-48, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24833217

RESUMEN

Root hair formation is controlled by environmental signals. We found significantly increased Arabidopsis root hair density and length in response to low-dose vanadate (V). Reactive oxygen species (ROS) production was induced with V treatment. We investigated the possible role of NADPH oxidase in altering root system architecture induced by V by using diphenylene iodonium (DPI), an inhibitor of NADPH oxidase, and an NADPH oxidase mutant (rhd2/AtrbohC). NADPH oxidase was involved in root hair elongation induced by V. As well, ethylene receptor (ETR1) and ROOT HAIR DEFECTIVE (RHD6) participated in inducing root hair formation induced by V. Furthermore, the kinase inhibitors, genistein (tyrosine kinase inhibitor) and K252a (ser/thr kinase inhibitor), and a phosphatase inhibitor, cantharidin (ser/thr phosphatase inhibitor), suppressed root hair formation induced by V. To elucidate the regulation of gene expression in response to V, we investigated transcriptional changes in roots by microarray assay. Exposure to V triggered changes in transcript levels of genes related to cell wall formation, ROS activity and signaling. Several genes involved in root hair formation were also regulated.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , NADPH Oxidasas/genética , Transducción de Señal/efectos de los fármacos , Vanadatos/farmacología , Arabidopsis/efectos de los fármacos , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/antagonistas & inhibidores , Proteínas de Arabidopsis/metabolismo , Cantaridina/farmacología , Pared Celular/metabolismo , Inhibidores Enzimáticos/farmacología , Perfilación de la Expresión Génica , Genes Reporteros , Genisteína/farmacología , Mutación , NADPH Oxidasas/antagonistas & inhibidores , NADPH Oxidasas/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Compuestos Onio/farmacología , Fenotipo , Fosforilación , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Especies Reactivas de Oxígeno/metabolismo , Plantones
4.
BMC Plant Biol ; 14: 94, 2014 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-24734953

RESUMEN

BACKGROUND: Arsenic (As) is a toxic metalloid found ubiquitously in the environment and widely considered an acute poison and carcinogen. However, the molecular mechanisms of the plant response to As and ensuing tolerance have not been extensively characterized. Here, we report on transcriptional changes with As treatment in two Arabidopsis accessions, Col-0 and Ws-2. RESULTS: The root elongation rate was greater for Col-0 than Ws-2 with As exposure. Accumulation of As was lower in the more tolerant accession Col-0 than in Ws-2. We compared the effect of As exposure on genome-wide gene expression in the two accessions by comparative microarray assay. The genes related to heat response and oxidative stresses were common to both accessions, which indicates conserved As stress-associated responses for the two accessions. Most of the specific response genes encoded heat shock proteins, heat shock factors, ubiquitin and aquaporin transporters. Genes coding for ethylene-signalling components were enriched in As-tolerant Col-0 with As exposure. A tolerance-associated gene candidate encoding Leucine-Rich Repeat receptor-like kinase VIII (LRR-RLK VIII) was selected for functional characterization. Genetic loss-of-function analysis of the LRR-RLK VIII gene revealed altered As sensitivity and the metal accumulation in roots. CONCLUSIONS: Thus, ethylene-related pathways, maintenance of protein structure and LRR-RLK VIII-mediated signalling may be important mechanisms for toxicity and tolerance to As in the species. Here, we provide a comprehensive survey of global transcriptional regulation for As and identify stress- and tolerance-associated genes responding to As.


Asunto(s)
Adaptación Fisiológica/genética , Arabidopsis/genética , Arabidopsis/fisiología , Arsénico/toxicidad , Perfilación de la Expresión Génica , Genes de Plantas , Transducción de Señal/genética , Adaptación Fisiológica/efectos de los fármacos , Arabidopsis/efectos de los fármacos , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , ADN Bacteriano/genética , Ecotipo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Ontología de Genes , Estudios de Asociación Genética , Mutación/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/genética , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Transducción de Señal/efectos de los fármacos , Estrés Fisiológico/efectos de los fármacos , Estrés Fisiológico/genética , Transcriptoma/efectos de los fármacos , Transcriptoma/genética
5.
Opt Express ; 22(5): 5183-95, 2014 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-24663858

RESUMEN

We introduce a type of LED light-gauge steel frame lamp with an adjustable illumination light field that does not require a diffusion plate. Base on the Monte Carlo ray tracing method, this lamp has a good glare rating (GR) of 17.5 at 3050 lm. Compared with the traditional LED light-gauge steel frame lamp (without diffusion plate), the new type has low GR. The adjustability of the illumination light field could improve the zebra effect caused by the inadequate illumination light field of the lamp. Meanwhile, we adopt the retinal image analysis to discuss the influence of GR on vision. High GR could reflect stray light on the retinal image, which will reduce vision clarity and hasten the feeling of eye fatigue.

6.
Sci Data ; 11(1): 335, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38575591

RESUMEN

Groundwater wells are critical infrastructure that enable the monitoring, extraction, and use of groundwater, which has important implications for the environment, water security, and economic development. Despite the importance of wells, a unified database collecting and standardizing information on the characteristics and locations of these wells across the United States has been lacking. To bridge this gap, we have created a comprehensive database of groundwater well records collected from state and federal agencies, which we call the United States Groundwater Well Database (USGWD). Presented in both tabular form and as vector points, USGWD comprises over 14.2 million well records with attributes, such as well purpose, location, depth, and capacity, for wells constructed as far back as 1763 to 2023. Rigorous cross-verification steps have been applied to ensure the accuracy of the data. The USGWD stands as a valuable tool for improving our understanding of how groundwater is accessed and managed across various regions and sectors within the United States.

7.
Plant Mol Biol ; 81(4-5): 507-22, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23400832

RESUMEN

The phytotoxic effects of copper (Cu) and cadmium (Cd) on plant growth are well documented. However, Cu and Cd toxicity targets and the cellular systems contributing to acquisition of tolerance are not fully understood at the molecular level. We aimed to identify genes and pathways that discriminate the actions of Cu and Cd in rice roots (Oryza sativa L. cv. TN67). The transcripts of 1,450 and 1,172 genes were regulated after Cu and Cd treatments, respectively. We identified 882 genes specifically respond to Cu treatment, and 604 unique genes as Cd-responsive by comparison of expression profiles of these two regulated gene groups. Gene ontology analysis for 538 genes involved in primary metabolism, oxidation reduction and response to stimulus was changed in response to both metals. In the individual aspect, Cu specifically altered levels of genes involved in vesicle trafficking transport, fatty acid metabolism and cellular component biogenesis. Cd-regulated genes related to unfolded protein binding and sulfate assimilation. To further characterize the functions of vesicle trafficking transport under Cu stress, interference of excytosis in root tissues was conducted by inhibitors and silencing of Exo70 genes. It was demonstrated that vesicle-trafficking is required for mediation of Cu-induced reactive oxygen species (ROS) production in root tissues. These results may provide new insights into understanding the molecular basis of the early metal stress response in plants.


Asunto(s)
Cadmio/toxicidad , Cobre/toxicidad , Oryza/efectos de los fármacos , Oryza/genética , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Transcriptoma/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Silenciador del Gen/efectos de los fármacos , Genes de Plantas/genética , Anotación de Secuencia Molecular , Análisis de Secuencia por Matrices de Oligonucleótidos , Oryza/crecimiento & desarrollo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , Virus de Plantas/efectos de los fármacos , Virus de Plantas/genética , Especies Reactivas de Oxígeno/metabolismo , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Plantones/efectos de los fármacos , Plantones/genética , Plantones/crecimiento & desarrollo , Estrés Fisiológico/efectos de los fármacos , Estrés Fisiológico/genética , Nicotiana/efectos de los fármacos , Nicotiana/genética , Nicotiana/virología , Transcriptoma/efectos de los fármacos , Vesículas Transportadoras/efectos de los fármacos , Vesículas Transportadoras/metabolismo
8.
PLoS One ; 18(3): e0283099, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36917584

RESUMEN

Cardiopulmonary resuscitation (CPR) education for the public may improve bystander intention to perform CPR on cardiac arrest patients. Studies have shown that different CPR education intervention methods can improve learning performance, with key indicators including attitude toward to CPR, intention to perform CPR, and degree of CPR knowledge and skills. The present study compared the traditional face-to-face method to hybrid and virtual reality (VR) methods to observe difference in learning performance and length of performance retention. This study adopted randomized controlled trial to compare CPR learning performance between traditional face-to-face, hybrid, and VR methods. Participants from each intervention group completed a pretest and 2 posttests. The measurement tools included an attitude and intention questionnaire, knowledge examination, and skill examination with a RESUSCI ANNE QCPR ® manikin. The performance among all participants in pretest showed no significant difference between the intervention groups, indicating no difference in their background attitude, knowledge, and skill level. Significant differences were observed in the average degree of intention to perform CPR between the hybrid and traditional groups in 1st and 2nd posttest. Compared to the pretest results, the posttests revealed significantly higher attitude toward CPR, intention to perform CPR, knowledge examination results, accuracy of overall chest compression, accuracy of CPR procedure, accuracy of AED usage, accuracy of chest compression rate, and accuracy of chest compression depth. The average time to reattending CPR learning and practice session was 11-12 weeks reported by participants. The hybrid and VR methods to CPR education resulted in the same level of improvement in learning performance as traditional face-to-face teaching. The suggested frequency for renewing CPR knowledge and skills is 12 weeks which may be considered in new strategies aimed at promoting CPR education and exposure to the public.


Asunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco , Humanos , Reanimación Cardiopulmonar/métodos , Universidades , Maniquíes , Estudiantes
9.
Plant Mol Biol ; 80(6): 587-608, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22987115

RESUMEN

Arsenic (As) is considered the most common toxic metalloid, but its molecular mode of action is not well understood. We investigated whether arsenate [As(V)] can induce intracellular reactive oxygen species production and calcium oscillation in rice roots. To better understand the molecular basis of plant cell responses to As, we performed a large-scale analysis of the rice transcriptome during As(V) stress. As(V) induced genes involved in abiotic stress, detoxification pathways and secondary metabolic process. Genes involved in secondary cell wall biogenesis, cell cycle and oligopeptide transport were mainly downregulated. Genes encoding signalling components such as receptor-like cytoplasmic kinases protein kinase, APETALA2/ethylene response factor, heat shock factor, MYB and zinc-finger protein expressed in inflorescence meristem transcription factors were increased in expression. The expression of GARP-G2-like and C3H transcription factors was specifically modulated by As(V) stress. The predominant families of As(V)-regulated transporters belonged to the ATP-binding cassette superfamily and telurite-resistance/dicarboxylate transporters. Several factors involved in signaling, such as mitogen-activated protein kinase (MAPK), MAPK kinase kinase and calcium-dependent protein kinase (CDPK), were also upregulated. Moreover, As(V) markedly increased the activity of MAPKs and CDPK-like kinases, and CDPK and NADPH oxidases were involved in As-induced MAPK activation. Further characterization of these As(V)-responsive genes and signalling pathways may help better understand the mechanisms of metalloid uptake, tolerance and detoxification in plants.


Asunto(s)
Arseniatos/toxicidad , Oryza/efectos de los fármacos , Oryza/genética , Arseniatos/farmacocinética , Señalización del Calcio/efectos de los fármacos , Contaminantes Ambientales/farmacocinética , Contaminantes Ambientales/toxicidad , Genes de Plantas/efectos de los fármacos , Inactivación Metabólica/genética , Inactivación Metabólica/fisiología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Modelos Biológicos , Oryza/metabolismo , Fitoquelatinas/metabolismo , Reguladores del Crecimiento de las Plantas/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Estrés Fisiológico , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcriptoma/efectos de los fármacos
10.
Plant Cell Physiol ; 53(8): 1457-69, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22706032

RESUMEN

Callus-forming capacity is enhanced with hypocotyl maturity in Arabidopsis. However, the genetic regulation of age-related gain in capacity for callus formation is unclear. We used a gene expression microarray assay to characterize the underlying mechanisms during callus formation in young and mature hypocotyl explants of Arabidopsis. As expected, genes involved in photosynthesis and cell wall thickening showed altered expression during hypocotyl maturation. In addition, genes involved in cytokinin perception were enriched in mature hypocotyl tissues. Phytohormone-induced callus formation in hypocotyl explants was accompanied by increased expression of genes mainly related to the cell cycle, histones and epigenetics. The induction level of these genes was higher in mature hypocotyl explants than young explants during callus formation. We identified a number of genes, including those with unknown function, potentially involved in age-related gain in callus formation. Our results provide insight into the effect of hypocotyl age on callus formation. Altered cytokinin signaling components, cell cycle regulation and epigenetics may work in concert to lead to gain of callus-forming capacity in hypocotyls with age.


Asunto(s)
Arabidopsis/fisiología , Hipocótilo/crecimiento & desarrollo , Hipocótilo/genética , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , División Celular/genética , Citocininas/genética , Citocininas/metabolismo , Epigénesis Genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Hipocótilo/anatomía & histología , Reguladores del Crecimiento de las Plantas/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Factores de Tiempo , Técnicas de Cultivo de Tejidos
11.
BMC Gastroenterol ; 12: 164, 2012 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-23170921

RESUMEN

BACKGROUND: There is increasing interest in balanced propofol sedation (BPS) titrated to moderate sedation (conscious sedation) for endoscopic procedures. However, few controlled studies on BPS targeted to deep sedation for diagnostic endoscopy were found. Alfentanil, a rapid and short-acting synthetic analog of fentanyl, appears to offer clinically significant advantages over fentanyl during outpatient anesthesia.It is reasonable to hypothesize that low dose of alfentanil used in BPS might also result in more rapid recovery as compared with fentanyl. METHODS: A prospective, randomized and double-blinded clinical trial of alfentanil, midazolam and propofol versus fentanyl, midazolam and propofol in 272 outpatients undergoing diagnostic esophagogastroduodenal endoscopy (EGD) and colonoscopy for health examination were enrolled. Randomization was achieved by using the computer-generated random sequence. Each combination regimen was titrated to deep sedation. The recovery time, patient satisfaction, safety and the efficacy and cost benefit between groups were compared. RESULTS: 260 participants were analyzed, 129 in alfentanil group and 131 in fentanyl group. There is no significant difference in sex, age, body weight, BMI and ASA distribution between two groups. Also, there is no significant difference in recovery time, satisfaction score from patients, propofol consumption, awake time from sedation, and sedation-related cardiopulmonary complications between two groups. Though deep sedation was targeted, all cardiopulmonary complications were minor and transient (10.8%, 28/260). No serious adverse events including the use of flumazenil, assisted ventilation, permanent injury or death, and temporary or permanent interruption of procedure were found in both groups. However, fentanyl is New Taiwan Dollar (NT$) 103 (approximate US$ 4) cheaper than alfentanil, leading to a significant difference in total cost between two groups. CONCLUSIONS: This randomized, double-blinded clinical trial showed that there is no significant difference in the recovery time, satisfaction score from patients, propofol consumption, awake time from sedation, and sedation-related cardiopulmonary complications between the two most common sedation regimens for EGD and colonoscopy in our hospital. However, fentanyl is NT$103 (US$ 4) cheaper than alfentanil in each case. TRIAL REGISTRATION: Institutional Review Board of Buddhist Tzu Chi General Hospital (IRB097-18) and Chinese Clinical Trial Registry (ChiCTR-TRC-12002575).


Asunto(s)
Alfentanilo/administración & dosificación , Periodo de Recuperación de la Anestesia , Anestésicos Intravenosos/administración & dosificación , Colonoscopía , Sedación Profunda , Fentanilo/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Alfentanilo/efectos adversos , Alfentanilo/economía , Anestésicos Intravenosos/efectos adversos , Anestésicos Intravenosos/economía , Sedación Profunda/efectos adversos , Sedación Profunda/economía , Método Doble Ciego , Endoscopía del Sistema Digestivo , Femenino , Fentanilo/efectos adversos , Fentanilo/economía , Humanos , Masculino , Midazolam , Persona de Mediana Edad , Satisfacción del Paciente , Propofol/administración & dosificación
12.
Environ Monit Assess ; 184(6): 3491-501, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21713462

RESUMEN

Stability of drinking water can be indicated by the assimilable organic carbon (AOC). This AOC value represents the regrowth capacity of microorganisms and has large impacts on the quality of drinking water in a distribution system. With respect to the effectiveness of traditional and advanced processing methods in removing trace organic compounds (including TOC, DOC, UV(254), and AOC) from water, experimental results indicate that the removal rate of AOC at the Cheng Ching Lake water treatment plant (which utilizes advanced water treatment processes, and is hereinafter referred to as CCLWTP) is 54%, while the removal rate of AOC at the Gong Yuan water treatment plant (which uses traditional water treatment processes, and is hereinafter referred to as GYWTP) is 36%. In advanced water treatment units, new coagulation-sedimentation processes, rapid filters, and biological activated carbon filters can effectively remove AOC, total organic carbon (TOC), and dissolved organic carbon (DOC). In traditional water treatment units, coagulation-sedimentation processes are most effective in removing AOC. Simulation results and calculations made using the AutoNet method indicate that TOC, TDS, NH(3)-N, and NO(3)-N should be regularly monitored in the CCLWTP, and that TOC, temperature, and NH(3)-N should be regularly monitored in the GYWTP.


Asunto(s)
Agua Potable/química , Compuestos Orgánicos/análisis , Contaminantes Químicos del Agua/análisis , Purificación del Agua/métodos , Carbono/análisis , Eliminación de Residuos Líquidos/métodos , Eliminación de Residuos Líquidos/estadística & datos numéricos , Purificación del Agua/estadística & datos numéricos
13.
J Psychiatr Res ; 121: 101-107, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31805472

RESUMEN

The clinical effects of electroconvulsive therapy (ECT) in treatment-resistant depressive disorders need to be systemically examined in representative samples. This study aimed to examine whether ECT reduced re-hospitalization within one year after discharge. The authors used the Psychiatric Inpatients Medical Claim Dataset, a subset of a total population health claims database from Taiwan, to include 784 inpatients with treatment-resistant depressive disorders screened for ECT during hospitalization between 2001 and 2011. The same number of comparison subjects was selected by frequency matching on the demographic and clinical characteristics. Using a mirror-image comparison design, we compared group differences in re-hospitalization rate, number of hospital days, number of emergency department visits, and direct medical costs during the 1-year pre- and post-ECT periods. The modifying effects of patients' characteristics on these outcomes were also explored. The results showed that ECT was associated with a significant decrease in the rate of hospitalizations and emergency department visits over the 1-year follow-up period. However, there were no significant difference in the reduced rate of hospitalizations between ECT and comparison group. Demographic and clinical characteristic had no modifying effect on the odds of psychiatric hospitalization. In conclusions, ECT could reduce the rate of hospitalization and number of emergency department visits in patients with treatment-resistant depressive disorders. However, the study results might be biased by the inherent deficits of mirror-image design.


Asunto(s)
Trastorno Depresivo Resistente al Tratamiento/terapia , Terapia Electroconvulsiva/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Adulto , Anciano , Femenino , Estudios de Seguimiento , Hospitalización/economía , Humanos , Masculino , Persona de Mediana Edad , Readmisión del Paciente/economía , Readmisión del Paciente/estadística & datos numéricos , Proyectos de Investigación , Taiwán , Adulto Joven
15.
Artículo en Inglés | MEDLINE | ID: mdl-18334354

RESUMEN

Epitaxial AlN films were prepared on GaN/sapphire using a helicon sputtering system at the low temperature of 300 degrees C. Surface acoustic wave (SAW) devices fabricated on AlN/GaN/sapphire exhibited superior characteristics compared with those made on GaN/sapphire. An oscillator using an AlN/GaN/sapphirebased SAW device is presented. The oscillation frequency decreased when the device was illuminated by ultraviolet (UV) radiation, and the downshift of the oscillation frequency increased with the illuminating UV power density. The results showed that the AlN/GaN/sapphire-layered structure SAW oscillators are suitable for visible blind UV detection and opened up the feasibility of developing remote UV sensors for different ranges of wavelengths on the III-nitrides.

16.
Oncotarget ; 7(10): 11067-82, 2016 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-26840563

RESUMEN

Hepatocyte growth factor (HGF) and its receptor c-Met were frequently deregulated in hepatocellular carcinoma (HCC). Signaling pathways activated by HGF-c-Met are promising targets for preventing HCC progression. HGF can induce the reactive oxygen species (ROS) signaling for cell adhesion, migration and invasion of tumors including HCC. On the other hand, extracellular signal-regulated kinases (ERK), member of mitogen activated kinase, can be activated by ROS for a lot of cellular processes. As expected, HGF-induced phosphorylation of ERK and progression of HCC cell HepG2 were suppressed by ROS scavengers. By N-(biotinoyl)-N'-(iodoacetyl)-ethylenediamine (BIAM) labeling method, a lot of cysteine (-SH)-containing proteins with M.W. 50-75 kD were decreased in HepG2 treated with HGF or two other ROS generators, 12-O-tetradecanoyl-phorbol-13-acetate (TPA) and phenazine methosulfate. These redox sensitive proteins were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Among them, two chaperones, heat shock protein 60 (HSP60) and protein disulfide isomerase (PDI), were found to be the most common redox sensitive proteins in responding to all three agonists. Affinity blot of BIAM-labeled, immunoprecipitated HSP60 and PDI verified that HGF can decrease the cysteine (-SH) containing HSP60 and PDI. On the other hand, HGF and TPA increased cysteinyl glutathione-containing HSP60, consistent with the decrease of cysteine (-SH)-containing HSP60. Moreover, depletion of HSP60 and PDI or expression of dominant negative mutant of HSP60 with alteration of Cys, effectively prevented HGF-induced ERK phosphorylation and HepG2 migration.In conclusion, the redox sensitive HSP60 and PDI are required for HGF-induced ROS signaling and potential targets for preventing HCC progressions.


Asunto(s)
Carcinoma Hepatocelular/patología , Movimiento Celular/fisiología , Chaperonina 60/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Neoplasias Hepáticas/patología , Proteínas Mitocondriales/metabolismo , Proteína Disulfuro Isomerasas/metabolismo , Animales , Carcinoma Hepatocelular/metabolismo , Activación Enzimática/fisiología , Células Hep G2 , Factor de Crecimiento de Hepatocito/metabolismo , Xenoinjertos , Humanos , Neoplasias Hepáticas/metabolismo , Ratones , Ratones SCID , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismo
17.
Ultrasonics ; 43(7): 566-73, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15950032

RESUMEN

A novel meander-line structure implemented with bimorph piezoelectric actuators driven by two sets of alternating current power with phase difference is developed in this article. Via the generated traveling wave, this mechanism is able to transport parts. The dynamic modeling of the structure, the driving control circuitry design, the motion trajectory analysis and the optimal transport feed rate is studied, and also verified by the practical experiment.

18.
Arch. Clin. Psychiatry (Impr.) ; 47(6): 199-208, Nov.Dec. 2020. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1248759

RESUMEN

ABSTRACT Background: The rapid outbreak of COVID-19 pandemic promptly changed people's daily lives, influenced human interactions and economic activities and induced mental reactions. Objective: This review synthesized the evidence of correlation between demographic factors, social media exposure, stressors and anxiety and depression status in the early phase of COVID-19. Method: A systematically search included observational studies published before May15, 2020. We selected studies designed with valid measuring instruments of anxiety and depression. Result: 20 articles were included (19 cross-sectional) for review. People who were divorced/widowed, with poor self-rated health status, chronic illness and previous psychiatric illness had higher anxiety and depression prevalence. Higher COVID-19 awareness (including COVID-19 knowledge and precautionary measure) decreased anxiety and depression. The protective measures to reduce anxiety and depression levels included avoiding sharing meals, frequently washing hands and wearing mask. Economic loss, academic delay, influence of daily life, worrying and symptoms related to infection were stressors of anxiety and depression. There were lots of inconsistent results due to convenience sampling and diverse measuring instrument. Conclusion: Our review suggested that reliable information from health authorities, enhancing health literacies and prevention measures of general population can reduce anxiety and depression levels.

19.
J Nanosci Nanotechnol ; 15(11): 9151-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26726660

RESUMEN

Monolayer transition-metal dichalcogenide is a very promising two-dimensional material for future transistor technology. Monolayer molybdenum disulfide (MoS2), owing to the unique electronic properties of its atomically thin two-dimensional layered structure, can be made into a high-performance metal-oxide-semiconductor field-effect transistor, or MOSFET. In this work, we focus on band structure and carrier mobility calculations for MoS2. We use the tight-binding method to calculate the band structure, including a consideration of the linear combination of different atomic orbitals, the interaction of neighboring atoms, and spin-orbit coupling for different tight-binding matrices. With information about the band structure, we can obtain the density of states, the effective mass, and other physical quantities. Carrier mobility using the Kubo-Greenwood formula is calculated based on the tight-binding band structure.

20.
Heart Rhythm ; 12(1): 163-6, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25176392

RESUMEN

BACKGROUND: There is still lack of strong evidence, based on systematic studies, that support the relationship between amiodarone use and the risk of acute pancreatitis. OBJECTIVE: The aim of this study was to explore the relationship between amiodarone use and the risk of acute pancreatitis in Taiwan. METHODS: This case-control study was based on the analysis of the claim data from Taiwan's national health insurance program from 2000 to 2011. There were 4986 subjects aged 20-84 years with a first episode of acute pancreatitis as the case group and 19,944 randomly selected subjects without acute pancreatitis matched for sex, age, and index year as the control group. Amiodarone use was defined as "current," "recent," or "past" if the most recent amiodarone prescription was filled within 3 months, between 3 and 6 months, or >6 months before the date of acute pancreatitis diagnosis, respectively. The relative risk of acute pancreatitis associated with amiodarone use was measured by the odds ratio with 95% confidence interval using the multivariable unconditional logistic regression model. RESULTS: After adjustment for confounding factors, current use of amiodarone was positively associated with acute pancreatitis (adjusted odds ratio 5.21; 95% confidence interval 3.22-8.43). There was no significant association between recent or past amiodarone use and acute pancreatitis. CONCLUSION: People with current use of amiodarone are at an increased risk of acute pancreatitis. Physicians should be more cautious about acute pancreatitis risk when prescribing amiodarone.


Asunto(s)
Amiodarona/uso terapéutico , Antiarrítmicos/uso terapéutico , Arritmias Cardíacas/tratamiento farmacológico , Pancreatitis/epidemiología , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Arritmias Cardíacas/complicaciones , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Taiwán/epidemiología , Adulto Joven
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