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An experimental investigation was carried out in a low-turbulence wind tunnel to study the early development of artificially initiated turbulent spots in a laminar boundary layer over a flat plate. The reproducibility of the experiments allowed us to observe fine structural details that have not been observed previously. Initial velocity disturbances quickly developed into hairpin-like structures that multiplied downstream, which increased the width, length and height of the incipient turbulent spots. Only those disturbances that were greater than a threshold value developed into turbulent spots while the others decayed. The rate of development was also affected by the duration of the initial disturbances. We found that the behaviour of turbulence generation within a turbulent spot is similar to the burst events in the turbulent boundary layer, where ejection events are followed by sweep events.
Major depressive disorder (MDD) is a common, debilitating, phenotypically heterogeneous disorder with heritability ranges from 30% to 50%. Compared to other psychiatric disorders, its high prevalence, moderate heritability, and strong polygenicity have posed major challenges for gene-mapping in MDD. Studies of common genetic variation in MDD, driven by large international collaborations such as the Psychiatric Genomics Consortium, have confirmed the highly polygenic nature of the disorder and implicated over 100 genetic risk loci to date. Rare copy number variants associated with MDD risk were also recently identified. The goal of this review is to present a broad picture of our current understanding of the epidemiology, genetic epidemiology, molecular genetics, and gene–environment interplay in MDD. Insights into the impact of genetic factors on the aetiology of this complex disorder hold great promise for improving clinical care.
Patulous Eustachian tube appears to be caused by a concave defect in the anterolateral wall of the tubal valve of the Eustachian tube. This study aimed to compare the clinical features of patulous Eustachian tube patients with or without a defect in the anterolateral wall of the tubal valve.
Sixty-six patients with a patulous Eustachian tube completed a questionnaire, which was evaluated alongside endoscopic findings of the tympanic membrane, nasal cavity and Eustachian tube orifice.
Females were more frequently diagnosed with a patulous Eustachian tube, but the valve defect was more common in males (p = 0.007). The ratio of patulous Eustachian tube patients with or without defects in the anterolateral wall of the tubal valve was 1.6:1. Weight loss in the previous six months and being refractory to conservative management were significantly associated with the defect (p = 0.035 and 0.037, respectively). Symptom severity was significantly higher in patients with the defect.
Patulous Eustachian tube patients without a defect in the anterolateral wall of the tubal valve can be non-surgically treated more often than those with the defect. Identification of the defect could assist in making treatment decisions for patulous Eustachian tube patients.
OBJECTIVES/GOALS: Lung transplant (LTx) candidates benefit from use of non-ideal donor organs. Each organ procurement organization (OPO) defines “acceptable” donor organs introducing unmeasured variation in donor pursuit. We characterized non-ideal donor pursuit among OPOs to identify drivers of risk aversion in LTx. METHODS/STUDY POPULATION: We queried the UNOS registry for adult donors who donated ≥1 organ for transplantation from 12/2007-12/2018. Non-ideal donors were those with any of age>50, smoking history ≥20 pack-years, PaO2/FiO2 (P/F) ratio<350, donation after cardiac death (DCD) status, or CDC increased risk (IRD) status. Non-ideal donor pursuit rate was defined as the proportion of non-ideal donors at each OPO from whom consent for lung donation was requested with lower numbers indicating increased risk aversion. We estimated the correlation between non-ideal and overall donor pursuit using a Spearman correlation coefficient. Adjusted non-ideal donor pursuit rates were estimated using multivariable logistic regression. RESULTS/ANTICIPATED RESULTS: Overall, 18,333 deceased donors were included and classified as ideal or non-ideal. Among 58 OPOs, rates of non-ideal donor pursuit ranged from 0.24-1.00 Figure). Of 5 non-ideal characteristics, DCD and IRD status were associated with the most and least risk aversion, respectively. Non-ideal donor pursuit was strongly correlated with overall donor pursuit (r = 0.99). On adjusted analysis, older age (OR 0.15, 95% CI 0.13-0.16), smoking history (OR 0.38, 95% CI 0.34-0.44), low P/F ratio (OR 0.12, 95% CI 0.11-0.14), and DCD status (OR 0.04, 95% CI 0.03-0.04) were all independently associated with significant risk aversion, corresponding to decreased rates of donor pursuit. DISCUSSION/SIGNIFICANCE OF IMPACT: OPOs differ in their levels of risk aversion in LTx and risk aversion is not uniform across selected categories of non-ideal lung donor. Consideration of new OPO performance metrics that encourage the pursuit of non-ideal lung donors is warranted.
To assess the Framingham risk score as a prognostic tool for idiopathic sudden sensorineural hearing loss patients.
Medical records were reviewed for unilateral idiopathic sudden sensorineural hearing loss patients between January 2010 and October 2017. The 10-year risk of developing cardiovascular disease was calculated. Patients were subdivided into groups: group 1 – Framingham risk score of less than 10 per cent (n = 28); group 2 – score of 10 to less than 20 per cent (n = 6); and group 3 – score of 20 per cent or higher (n = 5).
Initial pure tone average and Framingham risk score were not significantly associated (p = 0.32). Thirteen patients in group 1 recovered completely (46.4 per cent), but none in groups 2 and 3 showed complete recovery. Initial pure tone average and Framingham risk score were significantly associated in multivariable linear regression analysis (R2 = 0.36). The regression coefficient was 0.33 (p = 0.003) for initial pure tone average and −0.67 (p = 0.005) for Framingham risk score.
Framingham risk score may be useful in predicting outcomes for idiopathic sudden sensorineural hearing loss patients, as those with a higher score showed poorer hearing recovery.
Suicide is a serious phenomenon associated with psychiatric disorders.
In the present study, we investigated factors that can predict follow-up at the psychiatric clinic after medical care at the emergency room (ER).
Medical records of the 145 patients treated at the ER following suicide attempt from Jan 1, 2009 to July 31, 2009 were reviewed. Age, sex, past psychiatric history, impulsiveness and medical severity of suicide attempt, risk-rescue rating scores, reasons for suicide attempt and methods of suicide were examined. Psychiatric diagnoses were made by psychiatrists at the initial interview with patients at ER.
The mean age of the patients was 42.9 ± 15.7 years, and 68.3 % were women and 31.7% were men. Among the suicide methods, psychotropics were the most common (69%), and ingestion of pesticides was the second (19.3%). Interpersonal problems were the most common precipitating event (57.9%), and depression was the most common (89%). About a half had previous psychiatric disorders and about one third had previous suicide attempt. Fifteen patients (10.3%) attempted planned suicide and 124 patients (85.5%) attempted impulsively. Mean risk and rescue rating scores was 8.6 ±1.6 and 12.3 ± 2.2. About one third had a follow-up psychiatric visit. The most important predictor of psychiatric follow-up was risk rating scores.
This study suggests that women with interpersonal problems and depression should be carefully monitored to reduce suicide attempt. Patients commit less risky suicide attempts tend to more loss to psychiatric follow-up, thus, need more attention to prevent suicide re-attempts.
The prevalence of internet game use among children and adolescents has been increased in the recent years.
Internet addiction has been found to cause various psychiatric symptoms and psychological problems. Internet addiction has been found to cause various psychiatric symptoms and psychological problems.
The aim of this study was to examine the association between problematic internet game use and psychiatric symptoms in a sample of the Child and Adolescent Psychiatric Clinic, Ulsan University Hospital.
We analyzed data from 447 subjects who first visit the Child and Adolescent Psychiatric Clinic of the Ulsan University Hospital. The level of Internet addiction was categorized as either high-risk (≥108; group 3), potential risk (95 to 107; group 2), or no risk (≤94, group 1) based on the total score. Data were analyzed using SPSS version 17.0 and one-way ANOVA and multiple logistic regression method were used.
Thirteen adolescents met the criteria for high risk group of internet game addiction. in the high risk group, 10 were male and 3 were female adolescents. There was an mean difference among group 3 (high risk)< 1 (no risk),2 (potential risk) in AHI ; whereas group 3 (high risk)>1 (no risk), 2 (potential risk) in BDI, BAI, inattention, hyperactivity/impulsivity and K-ARS score. with multiple logistic regression analysis, K-scale was significantly related with male sex, BDI, ARShyperactivity/ impulsivity score.
We conclude that having male sex, happiness and depressive symptoms is associated with the risk of developing internet use disorders.
The binary metal oxides are increasingly used as supercapacitor electrode materials in energy storing devices. Particularly NiCo2O4 has shown promising electrocapacitive performance with high specific capacitance and energy density. The electrocapacitive performance of these oxides largely depends on their morphology and electrical properties governed by their energy band-gaps and defects. The morphological structure of NiCo2O4 can be altered via the synthesis route, while the energy band-gap could be altered by doping. Also, doping can enhance crystal stability and bring in grain refinement, which can further improve the much-needed surface area for high specific capacitance. Given the above, this study evaluates the electrochemical performance of Ca-doped Ni1-xCaxCo2O4 (0 ≤ x ≤ 0.8) compounds. This stipulates promising applications for electrodes in future supercapacitors.
To analyse how the auditory brainstem response changes in patients with sudden sensorineural hearing loss.
Data were collected via retrospective medical chart review.
Forty-three patients were included in this study. The mean latency of auditory brainstem response wave 1 was significantly longer for the affected side than for the unaffected side (p = 0.003). The mean latency of auditory brainstem response wave 1 was significantly shorter, and the mean amplitude of auditory brainstem response wave 1 was significantly larger, in the good response group compared to the poor response group. In forward conditional logistic regression analysis, auditory brainstem response wave 1 latency was an independent predictor of a good response (odds ratio = 34.37, 95 per cent confidence interval = 1.56–757.15, p = 0.025).
In patients with sudden sensorineural hearing loss, the latency of wave 1 of the auditory brainstem response was significantly increased and was related to prognosis.
The introduction of agriculture is known to have profoundly affected the ecological complexion of landscapes. In this study, a rapid transition from C3 to C4 vegetation is inferred from a shift to higher stable carbon (13C/12C) isotope ratios of soils and sediments in the Benoué River Valley and upland Fali Mountains in northern Cameroon. Landscape change is viewed from the perspective of two settlement mounds and adjacent floodplains, as well as a rock terrace agricultural field dating from 1100 cal yr BP to the recent past (<400 cal yr BP). Nitrogen (15N/14N) isotope ratios and soil micromorphology demonstrate variable uses of land adjacent to the mound sites. These results indicate that Early Iron Age settlement practices involved exploitation of C3 plants on soils with low δ15N values, indicating wetter soils. Conversely, from the Late Iron Age (>700 cal yr BP) until recent times, high soil and sediment δ13C and δ15N values reflect more C4 biomass and anthropogenic organic matter in open, dry environments. The results suggest that Iron Age settlement practices profoundly changed landscapes in this part of West Africa through land clearance and/or utilization of C4 plants.
To determine the factors related to multiple ventilation tube insertions in children with otitis media with effusion.
A retrospective review was performed of 126 ears of 81 children aged less than 12 years who had undergone insertion of a Paparella type 1 ventilation tube for the first time between August 2012 and March 2018.
Mean age at the first operation was 4.0 ± 2.2 years, and the mean duration of otitis media with effusion before the first ventilation tube insertion was 5.4 ± 4.5 months. Among 126 ears, 80 (63.5 per cent) had a single ventilation tube insertion and 46 (36.5 per cent) had multiple insertions. On multivariate logistic regression, tympanic membrane retraction, serous middle-ear discharge, and early recurrence of otitis media with effusion were independent predictive factors of multiple ventilation tube insertions.
Tympanic membrane retraction, serous middle-ear discharge, and early recurrence of otitis media with effusion after the first tube extrusion are associated with multiple ventilation tube insertions.
This project compares the degree of tracheal collapse determined by rigid and flexible bronchoscopy in paediatric patients with tracheomalacia.
A total of nine patients with tracheomalacia underwent both rigid and flexible video bronchoscopy. All patients were breathing spontaneously. Cross-sectional images of the airway were processed using the ImageJ program and analysed via colour histogram mode technique in order to delineate the luminal area. Paired t-tests (conducted using Stata software version 13.0) quantified differences between rigid and flexible bronchoscopes regarding the ratios of luminal pixels at maximum airway collapse to expansion. Correlation between both techniques in terms of airway collapse to expansion ratios was determined by calculating the Pearson correlation coefficient (R).
The difference in ratios of maximum collapse to expansion between rigid and flexible bronchoscopy was not statistically significant (p = 0.4656) and was positively correlated (R = 0.523).
The ratios suggest that rigid and flexible bronchoscopy are equally efficacious in assessing tracheomalacia severity, and may be used interchangeably in a clinical setting.
In this paper, we presented design specifications and operational test results of large-sized high temperature superconducting (HTS) magnets for Superconducting Induction Heater (SIH). HTS magnets were designed and fabricated with the metal insulation method. Critical currents of the HTS magnets were estimated by considering the angular dependency on the magnetic flux density of HTS tape. The characteristic resistance, the charging and discharging time were calculated and measured in the liquid nitrogen and the conduction cooling condition achieved with the 2nd stage GM cryo-cooler. The saturated temperature of the HTS magnet reached at 5.6 K. The performances of the large-sized HTS magnet including cooling and magnetic field characteristics were tested under the conduction cooling. These results were evaluated with those of finite element method analysis results. The characteristic analysis results of the large-sized HTS magnets will be applied for development of the commercial 300 kW SIH.
Whitehouse's theory on fusion can explain why suicide terrorists are willing to make the ultimate sacrifice for their groups, but the following questions on violent extremism remain: (a) Why are victims of suicide terrorism often innocent bystanders? (b) Why do terrorists seem motivated by ancient conflicts? We incorporate findings from the entitativity literature to provide insights into how perceptions of in-groups and out-groups are key processes influencing violent extremism.
It has not been well established whether dietary folate intake reduces the risk of diabetes development. We aimed to clarify the prospective association between dietary folate intake and type 2 diabetes (T2D) risk among 7333 Korean adults aged 40 years or older who were included in the Multi-Rural Communities Cohort. Dietary folate intake was estimated from all 106 food items listed on a FFQ, not including folate intake from supplements. Two different measurements of dietary folate intake were used: the baseline consumption and the average consumption from baseline until just before the end of follow-up. The association between folate intake and T2D risk was determined through a modified Poisson regression model with a robust error estimator controlling for potential confounders. For 29 745 person years, 319 cases of diabetes were ascertained. In multivariable analyses, dietary folate intake was inversely associated with risk of T2D for women, not for men. For women, the incidence rate ratio of diabetes in the third tertile compared with the first tertile was 0·57 (95 % CI 0·38–0·87, Pfor trend=0·0085) in the baseline consumption model and 0·64 (95 % CI 0·43–0·95, Pfor trend=0·0244) in the average consumption model. These inverse associations was found in both normal fasting blood glucose group and impaired fasting glucose group among women. Among non-users of multinutrients and vitamin supplements, the significant inverse association remained. Thus, higher dietary intake of folate is prospectively associated with lower risk of diabetes for women.
The purpose of this study was to investigate whether significant difference exists on radiation dose delivered to organs at risks in megavoltage computed tomography (MVCT) verification using three predefined scanning modes, namely fine (2 mm), normal (4 mm) and coarse (6 mm). This will provide information for the imaging protocol of tomotherapy for the left breast.
Materials and methods
Organ doses were measured using thermoluminescent dosimeters (TLD-100) placed within a female Rando phantom for MVCT imaging. Kruskal–Wallis test was conducted with p<0·05 to evaluate the significant difference between the three MVCT scanning modes.
Statistically significant difference existed in organ absorbed dose between different scan mode selections (p<0·001). Relative to the normal scan selection (4 mm), the absorbed dose to the organs of interests can be scaled down by 0·7 and scaled up by 2·1 for coarse (6 mm) and fine scans (2 mm) respectively.
Optimisation of imaging protocols is of paramount importance to keep the radiation exposure ‘as low as reasonably achievable’. The recommendation of undergoing daily coarse mode for MVCT verification in breast tomotherapy not only mitigates the radiation exposure to normal tissues, but also trims the scan-acquisition time.
We report on the astrometric registration of VLBI images of the SiO and H2O masers in OH 231.8+4.2, the iconic Proto-Planetary Nebula also known as the Calabash nebula, using the KVN and Source/Frequency Phase Referencing. This, for the first time, robustly confirms the alignment of the SiO masers, close to the AGB star, which drives the bi-lobe structure with the water masers in the out-flow.
A two-phase flow parametric study on an air induction nozzle with water and air as the working fluids is presented. Liquid was supplied at the pre-orifice with various inlet pressures ranging from 3 to 6 bar. The interaction between air and water at the molecular level at the orifice exit leads to formation of a strong shear layer that is intensified with the increase in inlet pressure. Thus, it is vital to regulate the ratio of the intake air to the supplied liquid so that the generated micro bubbles fit the design criteria. CFD analysis was conducted using the commercial software STAR CCM+ from Siemens and validated against experimental data to investigate the design parameters and their effect on the ALR. A volume of fluid (VOF) method of the RANS models was used to undertake the air-water interaction. Parameters such as the throat, air orifice, and air inlet diameter, along with the diffuser angle, were investigated. It was found that certain parameters such as the throat diameter have a more significant effect on the air/liquid entrainment ratio than other parameters.
A new approach is proposed to analyze Bremsstrahlung X-rays that are emitted from laser-produced plasmas (LPP) and are measured by a stack type spectrometer. This new method is based on a spectral tomographic reconstruction concept with the variational principle for optimization, without referring to the electron energy distribution of a plasma. This approach is applied to the analysis of some experimental data obtained at a few major laser facilities to demonstrate the applicability of the method. Slope temperatures of X-rays from LPP are determined with a two-temperature model, showing different spectral characteristics of X-rays depending on laser properties used in the experiments.