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1.
Opt Express ; 32(7): 11801-11817, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571019

RESUMEN

A full-quantum approach is used to study the quantum nonlinear properties of a compound Michelson-Sagnac interferometer optomechanical system. By deriving the effective Hamiltonian, we find that the reduced system exhibits a Kerr nonlinear term with a complex coefficient, entirely induced by the dissipative and dispersive couplings. Unexpectedly, the nonlinearities resulting from the dissipative coupling possess non-Hermitian Hamiltonian-like properties preserving the quantum nature of the dispersive coupling beyond the traditional system dissipation. This protective mechanism allows the system to exhibit strong quantum nonlinear effects when the detuning (the compound cavity detuning Δc and the auxiliary cavity detuning Δe) and the tunneling coupling strength (J) of two cavities satisfy the relation J2 = ΔcΔe. Moreover, the additive effects of dispersive and dissipative couplings can produce strong anti-bunching effects, which exist in both strong and weak coupling conditions. Our work may provide a new way to study and produce strong quantum nonlinear effects in dissipatively coupled optomechanical systems.

2.
Phys Rev E ; 107(2-1): 024220, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36932531

RESUMEN

The dynamics of chaos in quantum systems has attracted much interest in connection with the fundamental aspects of quantum mechanics. We study the chaotic dynamics of both the excitonic mode and the cavity mode in a microcavity containing a quantum well driven by an external field. We investigate how the chaotic dynamics is influenced by the frequencies of the exciton and the cavity, the coupling constant between the exciton and cavity, the Coulomb interaction between excitons, and the response of the exciton to the cavity and the external field. We show that chaos can be generated synchronously in both the cavity and the excitonic mode by choosing appropriate parameters. Moreover, this kind of chaos can be controlled by the coupling constant, the strength of the interaction between excitons, the external field, the response of the excitons to the cavity, and the detuning between the cavity field and the excitonic field. The present study may have applications in chaos-based neural networks and extreme event statistics.

3.
Plant Dis ; 2022 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-36190303

RESUMEN

Camptotheca acuminata (C. acuminata), is belongs to a monotypic genus endemic to southwestern China and listed as the first class national protected plant in China in 1999 (Wen, et al. 2020). Camptothecin, isolated from the wood and bark of C. acuminata Decne, which exhibits clinical effects in various cancer treatments (Pommier, et al. 2006; Kang, et al. 2021). In October 2021, we investigated leaf spot disease occurrence on C. acuminata (FigS1.A) with 80% incidence in Beichuan County, Sichuan Province of China. Leaf symptoms were randomly distributed on the adaxial surfaces and consisted of punctate spots of alternating light gray and dark brown in the early stage of onset (FigS1. B, C). As the disease progressed, these spots expanded irregularly shaped regions of necrotic tissue, and gray-white mildew layers can be seen on the front and back of the lesions in a humid environment. Infected tissues from symptomatic leaves disinfected in 75% ethanol for 45 s, and with 0.1% HgCl2 for 1 min, rinsed then plated on potato dextrose agar (PDA) medium supplemented with ampicillin and carbenicillin (50 µg/ml each). Plates were incubated for 3 days at 25°C. Then prepared by transferring hyphal tips from the edges of these colonies onto fresh PDA medium for subculture. Aerial hyphae had a cotton-like appearance with white to pale gray color (FigS1.D). Conidia were present in long chains, with conidiophores being present in clusters or in isolation (FigS1E), with 1-6 transverse septa, 0-3 oblique and longitudinal septa and an ellipsoidal to obpyriform structure, measuring 10.0-50.9 µm in length and 5.6-11.8 µm in width (n = 20) (FigS1E, G). On the basis of conidial and cultural characteristics, the fungus was consistent with those of members of the Alternaria genus (Simmons, 2008). To confirm this tentative identification, DNA was extracted from isolate XS9, the internal transcribed spacer rDNA regions (ITS), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), translation elongation factor 1-alpha (TEF1), partial RNA polymerase II largest subunit (RPB2) genes were amplified with primers pairs ITS1/ITS4 (White et al.1990), GDF/GDR (Templeton et al.), TEF-728F/TEF-986R (Carbone & Kohn 1999) and RPB2-5F2/RPB2-7cR (Sung et al. 1990; Liu et al. 1999), Bt-2a/Bt-2b (Glass and Donaldson 1995) respectively. The resulting sequences were deposited in GenBank (ITS, OP113690; GAPDH, OP120953; TEF, OP120952; RPB2, OP120954). Further phylogenetic analyses of isolate XS9 revealed it to cluster in the A. brassicae clade with 97% bootstrap support. Pathogenicity identification of isolate XS9 was carried out on the detached leaves. The pure agar plugs (as control) or spraying water on the leaf surface were inoculated on detached leaves, the controls remained healthy after 8 days (FigS1.H-J). but the leaves inoculated with other the mycelium plugs (Fig S1K, L) or the conidia suspension (2×105 conidia/mL) of isolate XS9 was sprayed on the detached leaves (Fig S1M, N), both showed brown necrotic lesions that are similar to the symptoms observed in the field. The pathogen was reisolated and confirmed to be A. brassicae. To our knowledge, this is the first report of leaf spot disease caused by A. brassicae on C. acuminata in China. Leaf spot disease causes the branches and leaves of camptotheca acuminata to wither and even the whole plant to die. To ensure the protection of the irreplaceable species, effective measures should be taken to prevent the spread of the leaf spot disease.

4.
Zhonghua Nan Ke Xue ; 24(2): 133-137, 2018 Feb.
Artículo en Chino | MEDLINE | ID: mdl-30156072

RESUMEN

OBJECTIVE: To compare the safety and effectiveness of shovel-shaped electrode transurethral plasmakinetic enucleation of the prostate (PKEP) with those of plasmakinetic resection of the prostate (PKRP) in the treatment of benign prostatic hyperplasia (BPH). METHODS: We retrospectively analyzed the clinical data about 78 BPH patients received in Shanghai Ninth People's Hospital from June 2016 to January 2017, 39 treated by shovel-shaped electrode PKEP and the other 39 by PKRP. We observed the patients for 6 months postoperatively and compared the effects and safety of the two surgical strategies. RESULTS: No statistically significant difference was observed between the PKEP and PKRP groups in the operation time (ï¼»69.3 ± 8.8ï¼½ vs ï¼»72.2 ± 7.9ï¼½ min, P = 0.126), but the former, as compared with the latter, showed a markedly less postoperative loss of hemoglobin (ï¼»3.9 ± 2.8ï¼½ vs ï¼»13.9 ± 5.2ï¼½ g/L, P <0.001) and shorter bladder irrigation time (ï¼»12.5 ± 1.2ï¼½ vs ï¼»43.4 ± 2.8ï¼½ h, P <0.001), catheterization time (ï¼»64.0 ± 4.5ï¼½ vs ï¼»84.8 ± 3.0ï¼½ h, P <0.001) and hospital stay (ï¼»3.1 ± 0.3ï¼½ vs ï¼»5.5 ± 0.4ï¼½ d, P <0.001). There were no statistically significant differences between the PKEP and PKRP groups in the postoperative maximum urinary flow rate (Qmax) (ï¼»21.62 ± 1.07ï¼½ vs ï¼»21.03 ± 0.96ï¼½ ml/s, P = 0.12), International Prostate Symptoms Score (IPSS) (5.85 ± 0.90 vs 6.03 ± 0.81, P = 0.279), quality of life score (QoL) (2.0 ± 0.73 vs 2.28 ± 0.72, P = 0.09), postvoid residual urine volume (PVR) (ï¼»19.59 ± 6.01ï¼½ vs ï¼»20.21 ± 5.16ï¼½ ml, P = 0.629), or the incidence rates of urinary incontinence (2.56% ï¼»1/39ï¼½ vs 7.69% ï¼»3/39ï¼½, P >0.05) and other postoperative complications. CONCLUSIONS: Both PKEP and PKRP are effective methods for the treatment of BPH, but PKEP is worthier of clinical recommendation for a better safety profile, more thorough removal of the prostate tissue, less blood loss, shorter hospital stay, and better improved quality of life of the patient.


Asunto(s)
Electrodos , Hiperplasia Prostática/cirugía , Resección Transuretral de la Próstata/métodos , China , Electrodos/efectos adversos , Diseño de Equipo , Humanos , Masculino , Calidad de Vida , Estudios Retrospectivos , Resección Transuretral de la Próstata/instrumentación , Resultado del Tratamiento
5.
Postgrad Med J ; 93(1106): 743-751, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28689171

RESUMEN

OBJECTIVE: Meta-analysis was used to assess the clinical efficacy of acupuncture treatment for simple obesity and to provide evidence-based medical data for treating obesity with acupuncture. METHODS: A comprehensive search of studies on MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials and Chinese databases (Wan Fang,CNKI and VIP) from 1 January 1915 through 30 November 2015 (MEDLINE search updated through 31 December 2015) was performed. We included only randomised controlled trials (RCTs) that used acupuncture and sham acupuncture to treat simple obesity. The effect of acupuncture on simple obesity was measured using body mass index (BMI), body fat mass (BFM), waist circumference (WC), hip circumference (HC), and body weight (BW). The Jadad scale was used to assess methodological quality. The random effects model was used in the pooled analysis to adjust for the heterogeneity of the included studies, and funnel plots were used to examine publication bias. The differences between treatment groups were reported as mean differences (MD). RESULTS: Eleven RCTs were selected after all relevant literature from the electronic databases had been screened. There were 338 and 305 participants in the acupuncture and sham acupuncture groups, respectively. Auricular and electro acupuncture were both able to reduce BMI in obese patients (MD 0.47 kg/m2, 95% CI 0.35 to 0.58, p<0.001; MD 0.50 kg/m2, 95% CI 0.38 to 0.62, p<0.001). BFM change after acupuncture treatment compared with sham treatment was statistically significant (MD 0.66 kg, 95% CI 0.51 to 0.80, p<0.001). There were also significant differences in WC and HC between the acupuncture and sham acupuncture groups (MDwc2.02 cm, 95% CI 0.21 to 3.83, p=0.03; MDHC2.74 cm, 95% CI 1.21 to 4.27, p=0.0004). BW was not statistically significantly different between the acupuncture and sham acupuncture groups (MD 0.60 kg, 95% CI -0.20 to 1.39, p=0.14). Begg's test and funnel plots showed that the potential publication bias of the included studies was very slight (p>0.05). CONCLUSION: Acupuncture for simple obesity appeared to be an effective treatment, but more studies on the safety of acupuncture used to treat simple obesity are required.


Asunto(s)
Terapia por Acupuntura , Obesidad/terapia , Adulto , Medicina Basada en la Evidencia , Humanos
6.
Huan Jing Ke Xue ; 37(1): 132-40, 2016 Jan 15.
Artículo en Chino | MEDLINE | ID: mdl-27078950

RESUMEN

In order to understand the aquatic community structure in the Laoyingyan section of the Dadu River, we collected samples from 9 aquatic sampling points along that section, and studied the phycophyta, zooplankton, benthic invertebrate and fish in them; we also used expert scoring method based on the actual situation of the river to weigh different biome. The water quality was evaluated using comprehensive evaluation of water quality index ( CEWI). The results showed that: (1) there were a total of 105 phycophyta species, belonging to 6 phyla,31 families, and 56 genera in the Laoyingyan section of the Dadu River, among which, diatom species had a higher richness than the others. The mean cell density of the phycophyta was 17.997 8 x 10(4) ind x L(-1), the mean biomass was 0.4463 mg x L(-1), and the highest population density sites were LTS, LYH and XSH. (2) there were a total of 26 zooplankton species, belonging to 3 phyla, 11 families, and 12 genera, among which, Protozoa had a higher richness than the others, accounting for 80.77% of all the zooplankton species; The mean density of the phycophyta was 40.89 ind x L(-1), and the mean biomass was 13.26 x 10(-3) mg x L(-1). The whole community composition was simple, characterized by few species and small population size. (3) there were a total of 14 benthic invertebrate species, belonging to 6 phyla,14 families, and 14 genera, among which, insecta had a higher richness than the others, accounting for 57.16% of the benthic invertebrate species. Benthic invertebrate had higher population densities in LYH and XSH. (4) The mean CEWI of the whole river water was 2. 698 28, characterized by slightly polluted water quality. The CEWI value between every collection point and the individual water quality evaluation index showed a significant positive correlation, manifesting a high consistency. In addition, the water quality of SLH and NYH was mesosaprobic (1 < CEWI < or = 2), and the water quality of LYH and LYY1 was clean (CEWI > 3), among which the worst was SLH with a lowest CEWI of 1.6207, and the best was LYH with a highest CEWI of 3.9545, all the other samples were subjected to different degrees of light pollution.


Asunto(s)
Biota , Ríos , Calidad del Agua , Animales , Biomasa , China , Diatomeas , Peces , Agua Dulce , Insectos , Invertebrados , Densidad de Población , Contaminación del Agua , Zooplancton
7.
J Med Virol ; 81(8): 1471-6, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19551830

RESUMEN

Influenza epidemic is an important cause of severe illness in the elderly. Age-dependent morbidity of influenza in the elderly is associated with weakened immunity. The baseline age-related memory T cell activity in Chinese persons who are exposed to influenza virus through natural infection, are associated with the protective response to the virus after vaccination, thus providing important pre-vaccination information. A cohort from the general population was established at the end of an influenza season in an area where influenza occurs regularly, and followed for 24 weeks. The subjects had no vaccination history for 5 years. Memory T cell responses were evaluated using a set of peptides spanning the influenza A (H3N2) entire proteome in a gamma interferon (IFN-gamma)-enzyme-linked immunospot (ELISPOT) assay, prior to the next influenza season. Changes of hemagglutination inhibition (HI) antibody titers were also evaluated. IFN-gamma(+) T cell responses against influenza peptides were significantly lower in subjects of 60 years and older. Although the age-related decline of cellular immune response was clear, no significant association of antibody titers with age was found. The pre-vaccination baseline of memory IFN-gamma(+) T cell immunity state in elderly Chinese was significantly lower than in people younger than 60 years. Measurement of the ex vivo cellular immune responses to influenza should be incorporated into the evaluation of protective immunity in elderly persons.


Asunto(s)
Memoria Inmunológica , Subtipo H3N2 del Virus de la Influenza A/inmunología , Gripe Humana/inmunología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/sangre , China , Estudios de Cohortes , Femenino , Pruebas de Inhibición de Hemaglutinación , Humanos , Interferón gamma/metabolismo , Masculino , Persona de Mediana Edad , Subgrupos de Linfocitos T/inmunología , Adulto Joven
8.
J Clin Virol ; 44(3): 225-9, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19186101

RESUMEN

BACKGROUND: H7 and H9 subtype avian influenza viruses pose a similar threat to humans as H5 virus. OBJECTIVES: This study aims to identify the potential existence of H7 and H9 avian influenza infections in farmers and in poultry workers in northern China regions with highly pathogenic avian influenza (HPAI) H5N1 outbreaks. STUDY DESIGN: Sera were collected from farmers in Xinjiang Uygur autonomous region and Liaoning province and poultry workers in Shandong province. Sera from healthy residents in Shanxi province were used as the controls. H7 and H9 virus infections were examined by hemagglutination inhibition (HI) assay using horse erythrocytes. The titer equal to or greater than 1:160 was considered positive. RESULTS: A total of 583 sera collected from farmers in Xinjiang were tested, and 10 (1.7%) were positive for H9 virus infection. Out of 200 sera collected from Liaoning, two (1.0%) were infected by H9 virus. No H7 virus infection was detected in the above serum samples. Neither H7 nor H9 virus infection was identified in 277 poultry workers of Shandong and in 407 residents of Shanxi. CONCLUSIONS: Although H9 virus infection was limited in farmers from Xinjiang and Liaoning, a public health alert is needed as novel pandemic influenza strains may develop unnoticed given the presence of subclinical infections, and the possibility of re-assortment with prevailing H5N1 virus in these regions.


Asunto(s)
Agricultura , Anticuerpos Antivirales/sangre , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Virus de la Influenza A/clasificación , Virus de la Influenza A/inmunología , Gripe Humana/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , Preescolar , China/epidemiología , Femenino , Pruebas de Inhibición de Hemaglutinación , Humanos , Subtipo H5N1 del Virus de la Influenza A/genética , Gripe Humana/diagnóstico , Masculino , Persona de Mediana Edad , Población Rural , Adulto Joven
9.
J Clin Microbiol ; 47(3): 814-6, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19109461

RESUMEN

Hepatitis E has been hypothesized as a zoonosis. However, there is no definite conclusion about which animal species contribute to hepatitis E virus (HEV) infection in humans. In this study, HEV RNA was detected only in swine bile specimens and not in bile specimens collected from cattle, goats, or dogs. We postulate that swine are the main animal reservoir for HEV.


Asunto(s)
Bilis/virología , Virus de la Hepatitis E/aislamiento & purificación , Hepatitis E/veterinaria , Enfermedades de los Porcinos/virología , Animales , Animales Domésticos , Bovinos , Enfermedades de los Bovinos/virología , China , Reservorios de Enfermedades/virología , Enfermedades de los Perros/virología , Perros , Enfermedades de las Cabras/virología , Cabras , Humanos , Datos de Secuencia Molecular , Porcinos
10.
J Virol Methods ; 153(1): 43-8, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18634828

RESUMEN

The hemagglutination inhibition (HI) assay is a widely used serological method to measure the levels of protective antibody responses against influenza viruses. However, the traditional HI assay which uses chicken erythrocytes is not sufficiently sensitive for detecting HI antibodies specific to avian influenza viruses. Previously, it was demonstrated that employing an assay using horse erythrocytes was able to increase the sensitivity of HI assay. The current report describes further optimization of this modified HI assay. It was shown that this method was able to increase detection of HI activities in rabbit sera immunized with H5 HA antigens, and proved that this increased sensitivity is useful in dissecting the strain specificity of HI antibody responses. In addition, the modified HI assay using horse erythrocytes increased the sensitivity of detecting HI antibodies specific for three major serotypes of avian influenza viruses, H5, H7 and H9, in people who may have asymptomatic infection with avian influenza viruses. Based on these results, the optimized use of horse erythrocytes should be standard practice for detecting HI activities against avian influenza viruses.


Asunto(s)
Anticuerpos Antivirales/sangre , Gripe Aviar/inmunología , Gripe Humana/inmunología , Animales , Pollos , Eritrocitos/virología , Pruebas de Inhibición de Hemaglutinación/métodos , Caballos , Humanos , Conejos , Sensibilidad y Especificidad
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