The psychometric characteristics of the revised depression attitude questionnaire (R-DAQ) in Pakistani medical practitioners: a cross-sectional study of doctors in Lahore

BACKGROUND: Depression is common mental health problem and leading contributor to the global burden of disease. The attitudes and beliefs of the public and of health professionals influence social acceptance and affect the esteem and help-seeking of people experiencing mental health problems. The attitudes of clinicians are particularly relevant to their role in accurately recognising and providing appropriate support and management of depression. This study examines the characteristics of the revised depression attitude questionnaire (R-DAQ) with doctors working in healthcare settings in Lahore, Pakistan. METHODS: A cross-sectional survey was conducted in 2015 using the revised depression attitude questionnaire (R-DAQ). A convenience sample of 700 medical practitioners based in six hospitals in Lahore was approached to participate in the survey. The R-DAQ structure was examined using Parallel Analysis from polychoric correlations. Unweighted least squares analysis (ULSA) was used for factor extraction. Model fit was estimated using goodness-of-fit indices and the root mean square of standardized residuals (RMSR), and internal consistency reliability for the overall scale and subscales was assessed using reliability estimates based on Mislevy and Bock (BILOG 3 Item analysis and test scoring with binary logistic models. Mooresville: Scientific Software, 55) and the McDonald's Omega statistic. Findings using this approach were compared with principal axis factor analysis based on Pearson correlation matrix. RESULTS: 601 (86%) of the doctors approached consented to participate in the study. Exploratory factor analysis of R-DAQ scale responses demonstrated the same 3-factor structure as in the UK development study, though analyses indicated removal of 7 of the 22 items because of weak loading or poor model fit. The 3 factor solution accounted for 49.8% of the common variance. Scale reliability and internal consistency were adequate: total scale standardised alpha was 0.694; subscale reliability for professional confidence was 0.732, therapeutic optimism/pessimism was 0.638, and generalist perspective was 0.769. CONCLUSIONS: The R-DAQ was developed with a predominantly UK-based sample of health professionals. This study indicates that this scale functions adequately and provides a valid measure of depression attitudes for medical practitioners in Pakistan, with the same factor structure as in the scale development sample. However, optimal scale function necessitated removal of several items, with a 15-item scale enabling the most parsimonious factor solution for this population

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

Intelligent Identification of Cavitation State of Centrifugal Pump Based on Support Vector Machine

In order to perform intelligent identification of the various stages of cavitation development, a micro high-speed centrifugal pump was used as a research object for vibration signal analysis and feature extraction for normal, incipient cavitation, cavitation and severely cavitated operating states of the pump at different temperatures (25 °C, 50 °C and 70 °C), based on support vector machines to classify and identify the eigenvalues in different cavitation states. The results of the study showed that the highest recognition rate of the individual eigenvalues of the time domain signals, followed by time frequency domain signals and finally frequency domain signals, was achieved in the binary classification of whether cavitation occurred or not. In the multi-classification recognition of the cavitation state, the eigenvalues of the time domain signals of the four monitoring points, the time frequency domain signals of the monitoring points in the X-direction of the inlet pipe and the Y-direction of the inlet pipe are combined, and the combined eigenvalues can achieve a multi-classification recognition rate of more than 94% for the cavitation state at different temperatures, which is highly accurate for the recognition of the cavitation state of centrifugal pumps

Investigation on the Handling Ability of Centrifugal Pumps under Air–Water Two-Phase Inflow: Model and Experimental Validation

The paper presents experimental and numerical investigations performed on a single stage, single-suction, horizontal-orientated centrifugal pump in air–water two-phase non-condensable flow conditions. Experimental measurements are performed in a centrifugal pump using pressure sensor devices in order to measure the wall static pressures at the inlet and outlet pump sections for different flow rates and rotational speeds combined with several air void fraction (a) values. Two different approaches are used in order to predict the pump performance degradations and perform comparisons with experiments for two-phase flow conditions: a one-dimensional two-phase bubbly flow model, and a full “Three-Dimensional Unsteady Reynolds Average Navier–Stokes” (3D-URANS) simulation using a modified k-epsilon turbulence model combined with the Euler–Euler inhomogeneous two-phase flow description. The overall and local flow features are presented and analyzed. Limitations concerning both approaches are pointed out according to some flow physical assumptions and measurement accuracies. Some additional suggestions are proposed in order to improve two-phase flow pump suction capabilities

Study on flow-induced noise propagation mechanism of cylinder–airfoil interference model by using large eddy simulation combined with vortex–acoustic equation

An innovative numerical prediction method of flow-induced noise is implemented to overcome the defect that the traditional acoustic analogy method cannot reflect the interaction between turbulence vortex and sound. The classical cylindrical–airfoil interference model is used to perform the simulation and compared with the experimental results. To start with the derivation of Powell’s vortex sound equation, an implicit three-dimensional model of the fluid–acoustic coupling field is established to process the unsteady iterative calculation. The large eddy simulation method is adopted to solve the unsteady flow, and the acoustic information is then calculated using the vortex acoustic equation at each iteration step. The vortex structures around the cylinder airfoil are identified and captured by the Q-criterion for further analysis of vortex–noise correlation mechanism. The flow-induced noise prediction results are finally compared with Ffowcs Williams–Hawkings (FW–H) acoustic analogy approach. The results show that the vortex shedding from the cylinder and the interaction between vortex shedding and airfoil have the greatest influence on the acoustic, and the far-field noise of the cylinder airfoil shows a partial “eight” dipole distribution. The calculated results of the vortex sound theory are closer to the experimental ones than the FW–H method. The research helps understand the vortex acoustic coupling mechanism of the cylinder–airfoil model and provides a more accurate numerical prediction of flow-induced noise

Determination of histamine in human plasma: the European external quality control study 1988

There is an increasing interest in measuring human plasma histamine levels in various clinical conditions. A variety of 'old' and newly developed techniques are applied to meet this demand. However, the discrepancy between reported reference values for histamine in human plasma measured using this variety of techniques, suggests the existence of a certain degree of inaccuracy and imprecision. We therefore organized an external quality control study on the reliability of current histamine determinations in European laboratories. Three lyophilized plasma quality control samples, in duplicate, covering the normal and pathological range of histamine concentrations (0-45 nmol/l), two different aqueous histamine standard samples and one solvent sample were sent to 10 laboratories for the analysis of their histamine content. The following methods were used: gas chromatography-mass spectrometry (n = 2), enzymatic single isotopic assay (n = 1), fluorometric-fluoroenzymatic assay (n = 3), radioimmunoassay (n = 3) and high performance liquid chromatography (n = 2). The study was performed and evaluated according to the approved recommendations (1983) of the International Federation of Clinical Chemistry (IFCC). The target values +/- s.d. of the three plasma samples were: 39.5 +/- 4.6 nmol/l (CV = 11.6%), 2.3 +/- 2.2 nmol/l (CV = 96%) and 8.9 +/- 1.5 nmol/l (CV = 17%), respectively.(ABSTRACT TRUNCATED AT 250 WORDS

Effects of the Herbicide Imazethapyr on Photosynthesis in PGR5- and NDH-Deficient <i>Arabidopsis thaliana</i> at the Biochemical, Transcriptomic, and Proteomic Levels

Photosynthesis is a very important metabolic pathway for plant growth and crop yield. This report investigated the effect of the herbicide imazethapyr on photosynthesis in the <i>Arabidopsis thaliana pns</i>B3 mutant (a defect in the NDH pathway) and <i>pgr</i>5 mutant (a defect in the PGR5 pathway) to determine which cyclic electron transport chain (CET) of the NDH and PGR5 pathways is more important for protecting the photosynthetic system under herbicide stress. The results showed that 20 μg/L imazethapyr markedly inhibited the growth of the three ecotypes of <i>A. thaliana</i> and produced more anthocyanins and reactive oxygen species (ROS), particularly in the <i>pgr</i>5 mutant. The chlorophyll fluorescence results showed that PSII was severely damaged in the <i>pgr</i>5 mutant. Additionally, the CET was significantly stimulated to protect the photosynthetic system from light damage in Wt and the <i>pns</i>B3 mutant but not the <i>pgr</i>5 mutant. The real-time PCR analysis indicated that imazethapyr treatment considerably decreased the transcript levels of most photosynthesis-related genes in the three treated groups. Several genes in the PGR5 pathway were significantly induced in the <i>pns</i>B3 mutant, but no genes in the NDH pathway were induced in the <i>pgr</i>5 mutant. The gene transcription analysis showed that the <i>pgr</i>5 mutant cannot compensate for the deficit in the PGR5 pathway by stimulating the NDH pathway, whereas the <i>pns</i>B3 mutant can compensate for the deficit in the CET cycle by regulating the PGR5 pathway. The iTRAQ analyses also showed that the photosynthesis system, glycolysis, and TCA cycle suffered the most severe damage in the <i>pgr</i>5 mutant. All of these results showed that the PGR5 pathway is more critical for electron transfer around PSI than the NDH pathway to resist herbicide stress

Small hydropower generation using pump as turbine; a smart solution for the development of Pakistan's energy

Energy supply that is sustainable, effective, and economical has a strong association with socio-economic growth, particularly in developing countries such as Pakistan. Due to the ever-increasing gap between supply and demand, Pakistan has become an energy-deficient nation, with most people having no-to-limited access to power. Pakistan has been suffering from power shortages and an energy crisis because of its strong reliance on fossil-fuels to provide expensive electricity. Therefore, this paper offers a novel concept for developing Pakistan's energy by producing small-hydropower using Pump-As-Turbine (PAT), which is a form of Renewable-energy with lower environmental-impact and has not been used in Pakistan previously. PATs have shown several advantages over traditional hydro-turbines, such as minimum expenses, low-complexity, short delivery time, ease of spare parts, easy installation, availability in a large number of standard sizes, and massive production for broad-range of heads and flow rates. According to technical standards, any sort of pump could be used as PAT, including radial, mixed, single-stage, multi-stage etc. for power generation, which are capable of producing 5kW–1000kW of power, depending on their usage. However, Pakistan has shown little to no interest in exploring small/micro hydropower generation (PATs technology). Thus, this study offers public awareness and forward thinking regarding the use of advanced SHPs and draws the interests of legislators and different investors via solid recommendations about the cost-effective and environmental-friendly technology (PAT)