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In this study, the aerodynamic characteristics of a vertical-axis wind turbine blade coupled with a high-lift device, such as the Gurney flap at the trailing edge, are investigated. For numerical analysis, the force element theory is used to understand how the Gurney flap influences the force evolution of the lift-type vertical-axis wind turbine. This study shows that the lift and drag can be respectively approximated into four elements, which are induced by volume vorticity, rotational velocity, angular acceleration and surface friction of the flow around the blades. Based on the perspective of the force element theory, the present simulation provides a clear picture of how the Gurney flap influences the formation of the aerodynamic force elements during a rotational cycle for a vertical-axis wind turbine. Simulation results show that the contributions mainly result from the surface vorticities, the rotational acceleration of the airfoil, and the acceleration of the surface.
Porphyromonas gingivalis has been linked to the development and progression of oesophageal squamous cell carcinoma (ESCC), and is considered to be a high-risk factor for ESCC. Currently, the commonly used methods for P. gingivalis detection are culture or DNA extraction-based, which are either time and labour intensive especially for high-throughput applications. We aimed to establish and evaluate a rapid and sensitive direct quantitative polymerase chain reaction (qPCR) protocol for the detection of P. gingivalis without DNA extraction which is suitable for large-scale epidemiological studies. Paired gingival swab samples from 192 subjects undergoing general medical examinations were analysed using two direct and one extraction-based qPCR assays for P. gingivalis. Tris-EDTA buffer-based direct qPCR (TE-direct qPCR), lysis-based direct qPCR (lysis-direct qPCR) and DNA extraction-based qPCR (kit-qPCR) were used, respectively, in 192, 132 and 60 of these samples for quantification of P. gingivalis. The sensitivity and specificity of TE-direct qPCR was 95.24% and 100% compared with lysis-direct qPCR, which was 100% and 97.30% when compared with kit-qPCR; TE-direct qPCR had an almost perfect agreement with lysis-direct qPCR (κ = 0.954) and kit-qPCR (κ = 0.965). Moreover, the assay time used for TE-direct qPCR was 1.5 h. In conclusion, the TE-direct qPCR assay is a simple and efficient method for the quantification of oral P. gingivalis and showed high sensitivity and specificity compared with routine qPCR.
Antipsychotic drugs (APDs) are the first-line pharmacological treatments for schizophrenia. Recent human studies have found that myelin integrity could be improved by APD treatment in schizophrenia patients. Previous studies indicated that regulation of oligodendrocyte development and function may be a novel target for APDs.
The aim of this current study was to examine the possible effects of the antipsychotic drugs (APDs) haloperidol (HAL), olanzapine (OLA), and quetiapine (QUE) on the development of oligodendroglial lineage cells.
CG4 cells, an oligodendrocyte progenitor cell line, were treated with various concentrations of HAL, OLA, or QUE for specific periods. The proliferation and differentiation of the CG4 cells were measured. The regulation of CG4 cell differentiation by oligodendrocyte lineage transcription factors 1 and 2 (Olig1 and Olig2) was examined.
The APDs used in this study had no effect on the proliferation of CG4 cells. The APDs elevated the expression of 2’,3’-cyclic nucleotide 3’-phosphodiesterase (CNP), a specific marker of oligodendrocytes, and promoted the CG4 cells to differentiate into CNP positive oligodendrocytes. QUE and OLA increased the expression of Olig1 and Olig2 whereas HAL only increased the expression of Olig2.
Our findings suggest that oligodendrocyte development is a target of HAL, OLA, and QUE and provide further evidence of the important role of oligodendrocytes in the pathophysiology and treatment of schizophrenia. They also indicate that the expression level of oligodendrocyte/myelinrelated genes could be profoundly affected by APDs.
We present the results from the abundance analysis of 21 primary stars in Sirius-like systems with various masses of white dwarf companions and orbital separation to understand the origin and nature of Ba stars. Three new Ba dwarfs are found for which masses are relatively low compared to Ba giants. Large fraction of the sample are found to be non-Ba stars, however, some of them have required WD mass and/or close orbital separation. Observed s-process abundances in Ba dwarfs are in good agreement with AGB models of respective WD companion mass, however, it required different pollution factors.
Hand-foot-mouth disease (HFMD) is an acute infectious disease caused by serotypes of the enterovirus (EV) family. HFMD reinfection occurs commonly in lack of cross-protection between different EV serotypes. In this study, we investigated the hazards of HFMD reinfection using Cox-proportional hazard model. Retrospective data of 95 209 HFMD cases in Wuhan during 2008–2015 was used. Kaplan–Meier survival methods and Cox-proportional hazard model were used to estimate the hazard probabilities. Of the all HFMD cases, about 2% experienced reinfection (1842/95 209). Kaplan–Meier curves revealed the reinfection risk sharply increased before 40 months from first infection. Higher hazards of reinfection were detected among those who were males, aged 3 years and below, scattered children, belonging to urban areas and first infected with coxsackievirus (CV)-A16 compared with their respective counterparts. Cox-proportional hazard model suggested that gender, age, group, living area and serotypes of first infection had significant effect on reinfection even after adjusting for potential confounding effects of other selected factors considered in the study. These results indicate that boys aged 3 years and below, especially those living in urban areas and first infected with CV-A16 are more prone to reinfection. Interventions should be imposed on these high-risk populations.
Simulation models are used widely in pharmacology, epidemiology and health economics (HEs). However, there have been no attempts to incorporate models from these disciplines into a single integrated model. Accordingly, we explored this linkage to evaluate the epidemiological and economic impact of oseltamivir dose optimisation in supporting pandemic influenza planning in the USA. An HE decision analytic model was linked to a pharmacokinetic/pharmacodynamics (PK/PD) – dynamic transmission model simulating the impact of pandemic influenza with low virulence and low transmissibility and, high virulence and high transmissibility. The cost-utility analysis was from the payer and societal perspectives, comparing oseltamivir 75 and 150 mg twice daily (BID) to no treatment over a 1-year time horizon. Model parameters were derived from published studies. Outcomes were measured as cost per quality-adjusted life year (QALY) gained. Sensitivity analyses were performed to examine the integrated model's robustness. Under both pandemic scenarios, compared to no treatment, the use of oseltamivir 75 or 150 mg BID led to a significant reduction of influenza episodes and influenza-related deaths, translating to substantial savings of QALYs. Overall drug costs were offset by the reduction of both direct and indirect costs, making these two interventions cost-saving from both perspectives. The results were sensitive to the proportion of inpatient presentation at the emergency visit and patients’ quality of life. Integrating PK/PD–EPI/HE models is achievable. Whilst further refinement of this novel linkage model to more closely mimic the reality is needed, the current study has generated useful insights to support influenza pandemic planning.
We investigated the first presence of qnrA among Shigella sonnei clinical isolates in Jiangsu Province, China. The qnrA-positive isolates coexisted with the mutation in gyrA at codon 83, these isolates were resistant to nalidixic acid and 22·2% (2 of 9) of them were resistant to norfloxacin.
Chronic rhinosinusitis is a common nasal disorder in children that is prone to recurrence. This study investigated the prevention of chronic rhinosinusitis recurrence with bacteria lysate in children.
Bacteria lysate was administered 10 days per month for 3 months to children with chronic rhinosinusitis, who had just entered a remission phase. Visual analogue score, nasal symptoms scores, rhinitis attack frequency and antibiotic use were assessed at three months and one year.
At one year of follow up, the visual analogue score, nasal discharge and obstruction scores, number of days with rhinitis attacks per month and number of days with antibiotic use per month were significantly decreased in the prevention group versus the control group (p < 0.05).
Bacterial lysate used in the remission period of rhinosinusitis in children was shown to provide long-term prophylaxis. Bacterial lysate can effectively reduce the frequency of rhinosinusitis attacks and ameliorate attack symptoms.
Repeat rectal chlamydia infection is common in men who have sex with men (MSM) following treatment with 1 g azithromycin. This study describes the association between organism load and repeat rectal chlamydia infection, genovar distribution, and efficacy of azithromycin in asymptomatic MSM. Stored rectal chlamydia-positive samples from MSM were analysed for organism load and genotyped to assist differentiation between reinfection and treatment failure. Included men had follow-up tests within 100 days of index infection. Lymphogranuloma venereum and proctitis diagnosed symptomatically were excluded. Factors associated with repeat infection, treatment failure and reinfection were investigated. In total, 227 MSM were included – 64 with repeat infections [28·2%, 95% confidence interval (CI) 22·4–34·5]. Repeat positivity was associated with increased pre-treatment organism load [odds ratio (OR) 1·7, 95% CI 1·4–2·2]. Of 64 repeat infections, 29 (12·8%, 95% CI 8·7–17·8) were treatment failures and 35 (15·4%, 95% CI 11·0–20·8) were reinfections, 11 (17·2%, 95% CI 8·9–28·7) of which were definite reinfections. Treatment failure and reinfection were both associated with increased load (OR 2·0, 95% CI 1·4–2·7 and 1·6, 95% CI 1·2–2·2, respectively). The most prevalent genovars were G, D and J. Treatment efficacy for 1 g azithromycin was 83·6% (95% CI 77·2–88·8). Repeat positivity was associated with high pre-treatment organism load. Randomized controlled trials are urgently needed to evaluate azithromycin's efficacy and whether extended doses can overcome rectal infections with high organism load.
We derive zphot for sources in the entire (~0.4 deg2) H-HDF-N field with the EAzY code, based on PSF-matched broad-band (U band to IRAC 4.5 μm) photometry. Our catalog consists of a total of 131,678 sources. We find σNMAD = 0.029 for non-X-ray sources. We also classify each object as a star or galaxy through SED fitting. Furthermore, we match our catalog with the 2 Ms CDF-N main X-ray catalog. For the 462 matched non-stellar X-ray sources, we improve their zphot quality (σNMAD = 0.035) by adding three additional AGN templates. We make our photometry and zphot catalog publicly available.
The paper studied the effect of an array of hemispherical substance-units (HSUs) immersed in inviscid and incompressible liquid on resonance frequency of a quartz crystal resonator (QCR) under the thickness-shear mode (TSM) vibrations. A dynamic model of the compound QCR system, consisting of a QCR and HSUs, was established in advance. The frequency equation of the compound QCR system including the liquid-solid coupling was derived subsequently. Numerical results showed the frequency-shift characteristics of the compound system. The obtained results are useful in resonator design and applications.
Trematode tyrosinases (TYRs) play a major role in the tanning process during eggshell formation. We investigated the molecular and biochemical features of Paragonimus westermani TYR (PwTYR). The PwTYR cDNA was composed of 1568-bp encompassing a 1422-bp-long open reading frame (474-amino acid polypeptide). A strong phylogenetic relationship with Platyhelminthes and Deuterostomian orthologues was evident. The recombinant PwTYR expressed in prokaryotic cells promptly oxidized diphenol substrates, with a preferential affinity toward ortho-positioned hydroxyl groups. It demonstrated fairly weak activity for monophenol compounds. Diphenol oxidase activity was augmented with an increase of pH from 5·0 to 8·0, while monophenol oxidase activity was highest at an acidic pH and gradually decreased as pH increased. Transcription profile of PwTYR was temporally upregulated along with worm development. PwTYR was specifically localized in vitellocytes and eggs. The results suggested that conversion of tyrosine to L-dihydroxyphenylalanine by PwTYR monophenol oxidase activity might be rate-limiting step during the sclerotization process of P. westermani eggs. The pH-dependent pattern of monophenol and diphenol oxidase activity further proposes that the initial hydroxylation might slowly but steadily progress in acidic secreted vesicles of vitellocytes and the second oxidation process might be rapidly accelerated by neural or weak alkaline pH environments within the ootype.
The impact of vanB vancomycin-resistant enterococci (VRE) bacteraemia on length of stay (LOS) in hospital, after adjusting for the time-varying nature of enterococcal bacteraemia (variable onset of bacteraemia post-admission), is unknown. Survival analyses (time-varying Cox and competing risks regression) were performed on vanB VRE bacteraemia patients, matched 1:1 with vancomycin-susceptible enterococci bacteraemia patients to determine the factors associated with LOS in these patients. In Cox regression analysis, vanB VRE bacteraemia, intensive-care-unit admission, Charlson co-morbidity index score ⩾4, and an increase in the time to receive appropriate antibiotics were associated with prolonged LOS. Competing risks regression which accounts for the influence of in-patient mortality on the ability to observe the event discharge alive from hospital suggests that, vanB VRE bacteraemia was not significantly associated with prolonged LOS. For the first time, the rate of discharge from hospital in patients with vanB VRE bacteraemia has been quantified.
Biological cells are major building blocks of tissues and organs of living organisms. These cells are also being used as biomarkers for diagnosis and sources for regenerative medicine. To better understand and even regulate diverse activities of cells, materials capable of interacting with cells have been designed by integrating various material chemistry, characterization, and processing techniques. These materials are often integrated with various nano- and microscale engineering devices. In this article, we provide an overview of materials for biological modulation, sensing, and imaging and also discuss opportunities for the future development of multifunctional materials for sensing and therapies.
The calcium-dependent protein kinases (CDPKs) are unique enzymes found only in plants, green algae, ciliates and apicomplexan parasites. In this study, a novel CDPK gene of Eimeria tenella, designed EtCDPK3, was cloned using rapid amplification of cDNA ends (RACE) based on the expressed sequence tag (EST). The entire cDNA of EtCDPK3 contained 1637 nucleotides encoding 433 amino acids and the deduced EtCDPK3 protein had canonical characteristic domains identified in other CDPKs, including a well-conserved amino-terminal kinase domain and a carboxy-terminal calmodulin-like structure with 4 EF-hand motifs for calcium binding. The expression profiles of the EtCDPK3 gene in different development stages were investigated by real-time quantitative PCR. Messenger RNA levels from the EtCDPK3 gene were higher in sporozoites than in other stages (unsporulated oocysts, sporulated oocysts and merozoites). Western blot analysis showed that rabbit antiserum against recombinant EtCDPK3 could recognize a native 49 kDa protein band of parasite. Indirect immunofluorescent antibody labelling revealed dispersed localization of EtCDPK3 during the first schizogony and intense specific staining. EtCDPK3 was located at the apical end of the sporozoites after early infection of DF-1 cells and the protein was highly expressed. Inhibition of EtCDPK3 function using specific antibodies reduced the ability of E. tenella to invade host cells. These results suggested that EtCDPK3 may be involved in invasion and survival of the parasite intracellular stages of E. tenella. Because this kinase family is absent from hosts, it represents a valid target that could be exploited for chemotherapy against Eimeria spp.
We report γ-ray afterglow observations of GRB 110625A using Fermi’s
Large Area Telescope (LAT) above 100 MeV. Gamma-ray emission was clearly detected using
data taken between 180 s and 580 s after the burst. The GeV light curve differs from a
power-law decay, and probably consists of two emission periods. Simultaneous Swift/XRT
observations did not show flaring behaviors, distinguishing its origin of the extended GeV
emission from the case of GRB 100728A.
Convergent studies provide support for abnormalities in the structure and functioning of the prefrontal cortex (PFC) and the amygdala, the key components of the neural system that subserves emotional processing in major depressive disorder (MDD). We used resting-state functional magnetic resonance imaging (fMRI) to examine potential amygdala–PFC functional connectivity abnormalities in treatment-naive subjects with MDD.
Resting-state fMRI data were acquired from 28 individuals with MDD and 30 healthy control (HC) subjects. Amygdala–PFC functional connectivity was compared between the MDD and HC groups.
Decreased functional connectivity to the left ventral PFC (VPFC) from the left and right amygdala was observed in the MDD group, compared with the HC group (p < 0.05, corrected).
The treatment-naive subjects with MDD showed decreased functional connectivity from the amygdala to the VPFC, especially to the left VPFC. This suggests that these connections may play an important role in the neuropathophysiology of MDD at its onset.
This study aimed to confirm that vertical transmission of hepatitis B virus (HBV) can occur via the infected ovum. Specimens studied were obtained from discarded test-tube embryos from mothers with chronic HBV infection who had received in vitro fertilization treatment. Single-cell reverse transcriptase–polymerase chain reaction was used to detect HBV mRNA in the embryos. HBV mRNA was detected in the cleavage embryos of patients with chronic HBV infection, with a detection rate of 13·2% (5/38). The level of serum HBV DNA was not related to the HBV mRNA positivity rates in embryos. In this study, HBV mRNA was detected in test-tube embryos from HBV-infected mothers who had received in vitro fertilization treatment. This confirms the theory of vertical transmission of HBV via the ovum, thereby providing an important theoretical basis for further study on the mechanism of HBV vertical transmission, influencing factors and blocking measures.
Anomalous X-ray pulsars (AXPs) are thought to be magnetars which are young isolated neutron stars with extremely strong magnetic fields of >1014 Gauss. Their tremendous magnetic fields inferred from the spin parameters provide a huge energy reservoir to power the observed X-ray emission. High-energy emission above 0.3 MeV has never been detected despite intensive search. Here, we present the possible Fermi Large Area Telescope (LAT) detection of γ-ray pulsations above 200 MeV from the AXP, 1E 2259+586, which puts the current theoretical models of γ-ray emission mechanisms of magnetars into challenge. We speculate that the high-energy γ-rays originate from the outer magnetosphere of the magnetar.