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1.
Opt Lett ; 48(5): 1148-1151, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36857235

RESUMEN

Anti-Stokes fluorescence (ASF) cooling has been demonstrated to be a viable method for balancing the waste heat produced in gain materials. In addition, radiation-balanced fiber lasers and amplifiers at atmospheric pressure have recently been developed. Here, we evaluate the cooling characteristics in a long section of a Yb-doped ZBLAN fiber with high pump power. The fiber has a 200-µm-diameter core and is doped with 3 wt. % Yb3+. As indicated by a thermal camera, cooling by over 7 K below ambient temperature was achieved by core pumping at 1030 nm. The temperature drop distribution at multiple measurement points in the fiber was evaluated with a maximum pump power of tens of watts. The results demonstrate the excellent ASF cooling performance of Yb-doped ZBLAN fibers. This study has great significance for the development of high-power radiation-balanced fiber lasers.

2.
Int J Clin Pract ; 2023: 5562495, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37609664

RESUMEN

Background: Tuberculosis (TB), a multisystemic disease with protean presentation, remains a major global health problem. Although concurrent pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB) cases are commonly observed clinically, knowledge regarding concurrent PTB-EPTB is limited. Here, a large-scale multicenter observational study conducted in China aimed to study the epidemiology of concurrent PTB-EPTB cases by diagnostically defining TB types and then implementing association rules analysis. Methods: The retrospective study was conducted at 21 hospitals in 15 provinces in China and included all inpatients with confirmed TB diagnoses admitted from Jan 2011 to Dec 2017. Association rules analysis was conducted for cases with concurrent PTB and various types of EPTB using the Apriori algorithm. Results: Evaluation of 438,979TB inpatients indicated PTB was the most commonly diagnosed (82.05%) followed by tuberculous pleurisy (23.62%). Concurrent PTB-EPTB was found in 129,422 cases (29.48%) of which tuberculous pleurisy was the most common concurrent EPTB type observed. The multivariable logistic regression models demonstrated that odds ratios of concurrent PTB-EPTB cases varied by gender and age group. For PTB cases with concurrent EPTB, the strongest association was found between PTB and concurrent bronchial tuberculosis (lift = 1.09). For EPTB cases with concurrent PTB, the strongest association was found between pharyngeal/laryngeal tuberculosis and concurrent PTB (lift = 1.11). Confidence and lift values of concurrent PTB-EPTB cases varied with gender and age. Conclusions: Numerous concurrent PTB-EPTB case types were observed, with confidence and lift values varying with gender and age. Clinicians should screen for concurrent PTB-EPTB in order to improve treatment outcomes.


Asunto(s)
Tuberculosis Extrapulmonar , Tuberculosis Pleural , Tuberculosis Pulmonar , Humanos , Tuberculosis Pleural/complicaciones , Tuberculosis Pleural/epidemiología , Estudios Retrospectivos , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/epidemiología , China/epidemiología
3.
Opt Express ; 30(25): 44434-44448, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36522868

RESUMEN

A new theory for the low coherence laser amplification in rare ions doped glass has been proposed. Based on one-dimensional continuous energy level assumption and independent response assumption, the theory can describe the amplification of low coherence laser pulses with any time scale and any bandwidth. By the new theory, McCumber formula can be obtained, and a complete low coherence optical pulse amplification model in neodymium glass is established. Computation shows that at high fluences, inhomogeneous broadening will severely limit energy extraction of narrowband high coherence laser, therefore the extraction of broadband low coherence laser will exceed that of narrowband high coherence laser. In addition, the portion of long-wave of the output spectrum is slightly larger than that predicted by the homogeneous model. The new theory could be beneficial for the studies of low coherence pulse amplification in rare earth doped medium and other laser mediums.

4.
Opt Express ; 30(12): 21906-21917, 2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-36224901

RESUMEN

We propose a random polarization smoothing method for low-coherence laser to obtain focal spot with random polarization that evolves rapidly in sub-picosecond timescales. Random polarization smoothing is realized by a half-aperture wave plate with sufficient thickness. The degree of polarization and polarization evolution of the focal spot are studied theoretically. The calculation results show that random polarization smoothing can make the polarization of focal spot evolve rapidly and randomly in time and space. Experimentally, the polarization of the focal spot of low-coherence laser with random polarization smoothing is measured by a single-shot polarimeter. The measurement results show that the degree of polarization of the focal spot is reduced to 0.22 on average, which proves the effectiveness of random polarization smoothing. The random polarization smoothing technique on low-coherence laser is expected to reduce the laser plasmas instability through its multi-dimensional random evolution properties.

5.
Opt Express ; 30(20): 35567-35579, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36258505

RESUMEN

Two new random polarization smoothing methods using full-aperture elements are proposed on low-coherence lasers, one using birefringent wedge and one using flat birefringent plate. By designing the crystal axis direction and wedge angle of the birefringent plates, the methods can selectively introduce time delay and spatial displacement, so as to obtain fast random evolution of transient polarization by utilizing low spatiotemporal coherence of the laser focal field. Both methods avoid the near field discontinuity and can be used under high fluence. The method using birefringent wedge can slightly improve focal spot uniformity, and the method using flat birefringent plate can obtain non-polarization with DOP lower than 2%. Theoretical studies show that the resulting focal polarization evolves rapidly on sub-picosecond timescales and rapidly covers the entire Poincaré sphere. The method using birefringent wedge is achieved in experiment. The results show that the degree of polarization of the focal spot is reduced from 1 to 0.27, which proves the effectiveness of the full-aperture random polarization smoothing. The full-aperture random polarization smoothing can generate a focal field very close to unpolarized thermal light, which is expected to suppress the laser plasmas instability.

6.
Eur J Clin Microbiol Infect Dis ; 40(4): 787-800, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33094354

RESUMEN

In clinical practice, PTB patients have concurrent many types of comorbidities such as pneumonia, liver disorder, diabetes mellitus, hematological disorder, and malnutrition. Detecting and treating specific comorbidities and preventing their development are important for PTB patients. However, the prevalence of most comorbid conditions in patients with PTB is not well described. We conducted a large-scale, multicenter, observational study to elucidate and illustrate the prevalence rates of major comorbidities in inpatients at 21 hospitals in China. The 19 specific comorbidities were selected for analysis in this patient cohort, and stratified the inpatient cohort according to age and gender. A total of 355,929 PTB inpatients were included, with a male:female ratio of 1.98 and the proportion of ≥ 65 years PTB inpatients was the most. Approximately 70% of PTB inpatients had at least one defined type of comorbidity. The prevalence of 19 specific comorbidities in inpatients with PTB was analyzed, with pneumonia being the most common comorbidity. The prevalence of most comorbidities was higher in males with PTB except thyroid disorders, mental health disorders, etc. The prevalence of defined most comorbidities in patients with PTB tended to increase with increasing age, although some specific comorbidities tended to increase initially then decrease with increasing age. Our study describes multiple clinically important comorbidities among PTB inpatients, and their prevalence between different gender and age groups. The results will enhance the clinical aptitude of physicians who treat patients with PTB to recognize, diagnose, and treat PTB comorbidities early.


Asunto(s)
Comorbilidad , Pacientes Internos , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/epidemiología , Adolescente , Adulto , Anciano , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven
7.
Opt Lett ; 45(24): 6839-6842, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33325909

RESUMEN

We report the first (to the best of our knowledge) high-power, low-coherence Nd:glass laser delivering kilojoule pulses with a coherent time of 249 fs and a bandwidth of 13 nm, achieving the 63%-efficiency second-harmonic conversion of the large-aperture low-coherence pulse and good beam smoothing effect. It provides a new type of laser driver for laser plasma interaction and high energy density physics research.

8.
Appl Opt ; 59(10): 2976-2982, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32400574

RESUMEN

The smoothing effect of induced spatial incoherence combined with a lens array on a large-bandwidth and short-coherence-time laser is reported. A theoretical model based on statistical optics is developed to describe the spatial and temporal characteristics of the focal spot. Theoretical simulation is consistent with the experimental results. A method was proposed to remove or reduce the residual interference fringes of the experimental focal spot, and both the simulation and analysis show that this method does not affect the smoothing speed of the focal spot.

9.
Opt Lett ; 44(17): 4359-4362, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31465402

RESUMEN

The nonlinear frequency conversion of low-temporal-coherent light holds a variety of applications and has attracted considerable interest. However, its physical mechanism remains relatively unexplored, and the conversion efficiency and bandwidth are extremely insufficient. Here, considering the instantaneous broadband characteristics, we establish a model of second-harmonic generation (SHG) of a low-temporal-coherent pulse and reveal its differences from the coherent conditions. It is found that the second-harmonic spectrum distribution is proportional to the self-convolution of that of a fundamental wave. Because of this, we propose a method for realizing low-temporal-coherent SHG with high efficiency and broad bandwidth, and experimentally demonstrate a conversion efficiency up to 70% with a bandwidth of 3.1 THz (2.9 nm centered at 528 nm). To the best of our knowledge, this is the highest efficiency and broadest bandwidth of low-temporal-coherent SHG to date. Our research opens the door for the study of low-coherent nonlinear optical processes.

10.
Liver Int ; 39(11): 2102-2111, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31379118

RESUMEN

BACKGROUND: Drug-induced liver injury (DILI) is the most common reason for a drug to be withdrawn from the market. Apart from stopping the offending drug, no regimens are available for treating idiosyncratic DILI in clinical practice. METHODS: We carried out a randomized, double-blind, multidoses, active drug controlled, multicentre phase II trial to assess the safety and efficacy of the study drug, magnesium isoglycyrrhizinate (MgIG), as compared to tiopronin, a standard therapy for DILI in China. The primary outcome was the proportion of alanine aminotransferase (ALT) normalization at week 4 after study drug administration. Logistic regression was used to examine the odds of ALT normalization between low dose (Group A) and high dose (Group B) vs active control (Group C). RESULTS: One hundred and seventy-four eligible subjects were randomized and enrolled into three groups: 59 in group A, 56 in group B and 59 in group C. It was shown that group A and group B lowered ALT level even at early stage of study drug administration; when compared with Group C (61.02%), the proportions of ALT normalization at week 4 were significantly greater in Group A (84.75%, P = .0029) and Group B (85.71%, P = .0037) respectively. The results from the univariate logistic model showed that the odds of ALT normalized among subjects in Group A were about 3.6 times greater (OR = 3.55, 95% CI: 1.47-8.57, P = .0049) than subjects in Group C. Similar effect was observed among subjects in Group B (OR = 3.83, 95% CI: 1.54-9.55, P = .0039). CONCLUSIONS: This trial provided preliminary evidence that MgIG is an effective and safe treatment for patients with acute DILI.


Asunto(s)
Alanina Transaminasa/sangre , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Saponinas/administración & dosificación , Triterpenos/administración & dosificación , Adulto , Enfermedad Hepática Inducida por Sustancias y Drogas/sangre , China , Método Doble Ciego , Femenino , Humanos , Inyecciones Intravenosas , Hígado/efectos de los fármacos , Hígado/patología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Saponinas/efectos adversos , Triterpenos/efectos adversos , Adulto Joven
11.
Appl Opt ; 58(8): 2121-2126, 2019 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-30874076

RESUMEN

The smoothing scheme combining a diffraction-weakened lens array with the induced spatial incoherence method is proposed and demonstrated to be an efficient smoothing scheme for broadband laser systems. In our simulation, the RMS illumination nonuniformity of the target spot is reduced to 2% after sufficient smoothing time. The temporal characteristics and spatial power spectral density of the scheme are theoretically analyzed. When the incident light has intensity fluctuations, the uniformity of the target spot is stable, which means a robust smoothing scheme, and which predicts practical applications to the smoothing of broadband laser systems.

12.
Artículo en Inglés | MEDLINE | ID: mdl-29378718

RESUMEN

We performed a multicenter, prospective, randomized study to investigate the efficacy and safety of clofazimine (CLO) for treatment of extensively drug-resistant tuberculosis (XDR-TB) in China. Forty-nine patients infected with XDR-TB were randomly assigned to either the control group or the CLO group, both of which received 36 months of individually customized treatment. The primary endpoint was the time to sputum culture conversion on solid medium. Clinical outcomes of patients were evaluated at the time of treatment completion. Of the 22 patients in the experimental group, 7 (31.8%) met the treatment criterion of "cure" and 1 (4.5%) "complete treatment," for a total of 8 (36.4%) exhibiting successful treatment outcomes without relapse. In the control group, 6 patients (22.2%) were cured and 6 (22.2%) completed treatment by the end of the study. Statistical analysis revealed no significant difference in successful outcome rates between the CLO group and the control group. The average sputum culture conversion time for the experimental group was 19.7 months, which was not statistically different from that for the control group (20.3 months; P = 0.57). Of the 22 patients in the CLO group, 12 (54.5%) experienced adverse events after starting CLO treatment. The most frequently observed adverse event was liver damage, with 31.8% of patients (7/22 patients) in the CLO group versus 11.1% (3/27 patients) in the control group exhibiting this adverse event. Our study demonstrates that inclusion of CLO in background treatment regimens for XDR-TB is of limited benefit, especially since hepatic disorders arise as major adverse events with CLO treatment. (This study is registered with the Chinese Clinical Trial Registry [ChiCTR, www.chictr.org.cn] under identifier ChiCTR1800014800.).


Asunto(s)
Antituberculosos/uso terapéutico , Clofazimina/uso terapéutico , Tuberculosis Extensivamente Resistente a Drogas/tratamiento farmacológico , Adulto , Anciano , Antituberculosos/efectos adversos , China , Clofazimina/efectos adversos , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Tuberculosis Resistente a Múltiples Medicamentos
15.
Clin Infect Dis ; 60(9): 1361-7, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25605283

RESUMEN

BACKGROUND: Clofazimine (Cfz) has shown activity against Mycobacterium tuberculosis, including multidrug-resistant (MDR) strains in vitro and in animal studies. Here we evaluate the clinical efficacy and tolerability of using Cfz to treat MDR tuberculosis in China. METHODS: We enrolled 105 patients who had sputum culture-positive MDR tuberculosis in 6 major tuberculosis specialty hospitals in China. Patients were randomly assigned to either the Cfz therapy group (n = 53) or control group (n = 52). Patients in the 2 groups were given 21 months of individual-based chemotherapy regimens based on medication history and drug susceptibility test results. The Cfz therapy group regimens incorporated 100 mg of Cfz once daily for 21 months. RESULTS: Three patients in each group discontinued therapy because of side effects or other reasons. Sputum culture conversion to negative was earlier in patients who received Cfz compared with controls (P = .042 by log-rank test). Chest computed tomography showed cavitary changes in 46 patients in the Cfz therapy group and 45 in the control group. Cavity closure was earlier in patient who received Cfz compared with controls (P = .047 by log-rank test). The treatment success rate in the Cfz group was 73.6%, higher than that in control group (53.8%; P = .035). Side effects in skin only occurred in the Cfz group. The rates of skin discoloration and ichthyosis were 94.3% and 47.2%, respectively. CONCLUSIONS: Using Cfz to treat MDR tuberculosis promotes cavity closure, accelerates sputum culture conversion, and improves treatment success rates.


Asunto(s)
Antituberculosos/uso terapéutico , Clofazimina/uso terapéutico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Pulmonar/tratamiento farmacológico , Adolescente , Adulto , China , Clofazimina/administración & dosificación , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Esputo/microbiología , Resultado del Tratamiento , Tuberculosis Pulmonar/microbiología , Adulto Joven
17.
Environ Sci Technol ; 49(8): 5227-35, 2015 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-25810405

RESUMEN

Sustained current generation by anodic biofilms is a key element for the longevity and success of bioelectrochemical systems. Over time, however, inactive or dead cells can accumulate within the anode biofilm, which can be particularly detrimental to current generation. Mixed and pure culture (Geobacter anodireducens) biofilms were examined here relative to changes in electrochemical properties over time. An analysis of the three-dimensional metabolic structure of the biofilms over time showed that both types of biofilms developed a live outer-layer that covered a dead inner-core. This two-layer structure appeared to be mostly a result of relatively low anodic current densities compared to other studies. During biofilm development, the live layer reached a constant thickness, whereas dead cells continued to accumulate near the electrode surface. This result indicated that only the live outer-layer of biofilm was responsible for current generation and suggested that the dead inner-layer continued to function as an electrically conductive matrix. Analysis of the electrochemical properties and biofilm thickness revealed that the diffusion resistance measured using electrochemical impedance spectroscopy might not be due to acetate or proton diffusion limitations to the live layer, but rather electron-mediator diffusion.


Asunto(s)
Biopelículas , Espectroscopía Dieléctrica , Geobacter/fisiología , Acetatos/metabolismo , Biopelículas/crecimiento & desarrollo , Electrodos , Electrones , Geobacter/química , Geobacter/metabolismo , Análisis Espacio-Temporal
18.
Mol Biol Rep ; 40(8): 5073-83, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23653008

RESUMEN

The MRC1 gene, encoding the human mannose receptor (MR), is a member of the C-type lectin receptors family. MR can recognize and bind to Mycobacterium tuberculosis by the extracellular structure, and play a role in antigen-presenting and maintaining a stable internal environment. This study aimed to investigate potential associations of SNPs in exon 7 of the MRC1 gene with pulmonary tuberculosis (TB). G1186A, G1195A, T1212C, C1221G, C1303T and C1323T were genotyped using PCR and DNA sequencing in 595 Chinese Uygur and 513 Kazak subjects. In the Uygur, the frequency of allele G (P=0.031, OR=1.29, 95% CI=1.02-1.62) and AA genotype (P=0.033, OR=1.64, 95% CI=1.04-2.60) for G1186A was lower in the pulmonary TB than healthy control and were significantly correlated with pulmonary TB. After adjustment for age and gender, G1186A was found to be additive models in association with pulmonary TB (P=0.04, OR=1.27, 95% CI=1.01-1.60). By calculating linkage disequilibrium, the frequency of haplotype GGTCCT (P=0.032, OR=0.75, 95% CI=0.57-0.97) and GGTCCC (P=0.044, OR=0.57, 95% CI=0.33-0.99) was significantly associated with pulmonary TB. No association was found between other SNPs and pulmonary TB. In the Kazak, all SNPs were not associated with pulmonary TB. Our results suggest that genetic factors play an important role in susceptibility to pulmonary TB at the individual level, and provide an experimental basis to clarify the pathogenesis of pulmonary TB.


Asunto(s)
Etnicidad/genética , Predisposición Genética a la Enfermedad/genética , Receptores Inmunológicos/genética , Tuberculosis Pulmonar/genética , Adulto , Factores de Edad , Anciano , China , Exones/genética , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Genotipo , Haplotipos/genética , Humanos , Desequilibrio de Ligamiento , Masculino , Glicoproteínas de Membrana , Persona de Mediana Edad , Modelos Genéticos , Polimorfismo de Nucleótido Simple/genética , Factores Sexuales
19.
Plant Physiol Biochem ; 195: 47-57, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36599275

RESUMEN

Nitrogen (N) is an essential nutrient element required for plant growth, and the development of wheat varieties with high nitrogen use efficiency (NUE) is an urgent need for sustainable crop production. However, the molecular mechanism of NUE between diverse wheat varieties in response to N application remains unclear. To reveal the possible molecular mechanisms underlying this complex phenomenon, we investigated the transcriptional and metabolic changes of flag leaves of two wheat near-isogenic lines (NILs) differing in NUE under two N fertilizer treatments. Comparative transcriptome analysis indicated that the expression levels of the genes responsible for carbon and nitrogen metabolism were significantly higher in high-NUE wheat. The metabolome comparison revealed that the activity of the tricarboxylic acid (TCA) cycle was enhanced in high-NUE wheat, while reduced in low-NUE wheat after the N fertilizer application. Additionally, amino acid metabolism increased in both wheat NILs but more increased in high-NUE wheat. In summary, more upregulated transcripts and metabolites were identified in high-NUE wheat, and this study provides valuable new insights for improving NUE in wheat.


Asunto(s)
Transcriptoma , Triticum , Triticum/metabolismo , Nitrógeno/metabolismo , Fertilizantes , Perfilación de la Expresión Génica
20.
BMC Infect Dis ; 12: 91, 2012 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-22502597

RESUMEN

BACKGROUND: The present study aimed to investigate the genetic polymorphisms in exon 4 of the NOD2 gene in tuberculosis patients and healthy controls, in order to clarify whether polymorphisms in the NOD2 gene is associated with tuberculosis. METHODS: A case-control study was performed on the Chinese Han, Uygur and Kazak populations. Exon 4 of the NOD2 gene was sequenced in 425 TB patients and 380 healthy controls to identify SNPs. RESULTS: The frequency of T/G genotypes for the Arg587Arg (CGT → CGG) single nucleotide polymorphism (SNP) in NOD2 was found to be significantly higher in the Uygur (34.9%) and Kazak (37.1%) populations than the Han population (18.6%). Also, the frequency of G/G genotypes for the Arg587Arg SNP was significantly higher in the Uyghur (8.3%) and Kazak (5.4%) populations than the Han population (0.9%). Meanwhile, no significant difference was found in the Arg587Arg polymorphism between the tuberculosis patients and healthy controls in the Uyghur and Kazak populations (P > 0.05) whereas, a significant difference was observed in the Arg587Arg polymorphism between the tuberculosis patients and healthy controls in the Han population (P < 0.01). The odd ratio of 2.16 (95% CI = 1.31-3.58; P < 0.01) indicated that the Arg587Arg SNP in NOD2 may be associated with susceptibility to tuberculosis in the Chinese Han population. CONCLUSIONS: Our study is the first to demonstrate that the Arg587Arg SNP in NOD2 is a new possible risk factor for tuberculosis in the Chinese Han population, but not in the Uyghur and Kazak populations. Our results may reflect racial differences in genetic susceptibility to tuberculosis.


Asunto(s)
Predisposición Genética a la Enfermedad , Proteína Adaptadora de Señalización NOD2/genética , Polimorfismo de Nucleótido Simple , Tuberculosis Pulmonar/genética , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , China , Etnicidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ADN , Tuberculosis Pulmonar/etnología , Adulto Joven
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