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This study investigated the impact of spiritual intelligence and demographic factors in the prediction of occupational stress, quality of life and coronavirus anxiety among nurses.A cross-sectional study was planned.The study was conducted among full-time nurses who were employed in two teaching hospitals of Babol city which were referral centres for caring patients infected with COVID-19 from February-May 2021. One hundred and twenty-nine nurses completed five questionnaires including the demographic questions, Quality of life (WHOQOL-BRIF), Occupational Role Questionnaire (ORQ), Spiritual Intelligence and Coronavirus Anxiety Scale.The findings revealed that 69% of the nurses experienced moderate occupational stress, moderate quality of life and low coronavirus anxiety. Spiritual intelligence was the only significant negative predictor of occupational stress (β = -0.517, p = 0.001). The only positive predictor of quality of life was perceived income adequacy. Predicting factors of coronavirus anxiety were the perceived income adequacy as protective (β = -0.221, p = 0.022) and the number of children as predisposing (β = 0.401, p = 0.004) factors. These findings should be considered when planning nursing interventions for improvement of occupational stress, quality of life and anxiety especially during crises like the COVID-19 pandemic.

The determination of suitable testing and qualification procedures for fiber-reinforced polymer matrix composite structures is an active area of research due to the increased demand, especially in the field of aerospace. This research illustrates the development of a generic qualification framework for a composite-based main landing gear strut of a lightweight aircraft. For this purpose, a landing gear strut composed of T700 carbon fiber/epoxy material was designed and analyzed for a given lightweight aircraft having mass of 1600 kg. Computational analysis was performed on ABAQUS CAE® to evaluate the maximum stresses and critical failure modes encountered during one-point landing condition as defined in the UAV Systems Airworthiness Requirements (USAR) and Air Worthiness Standards FAA FAR Part 23. A three-step qualification framework including material, process and product-based qualification was then proposed against these maximum stresses and failure modes. The proposed framework revolves around the destructive testing of specimens initially as per ASTM standards D 7264 and D 2344, followed by defining the autoclave process parameters and customized testing of thick specimens to evaluate material strength against the maximum stresses in specific failure modes of the main landing gear strut. Once the desired strength of the specimens was achieved based on material and process qualifications, qualification criteria for the main landing gear strut were proposed which would not only serve as an alternative to drop test the landing gear struts as defined in air worthiness standards during mass production, but would also give confidence to manufacturers to undertake the manufacturing of main landing gear struts using qualified material and process parameters.

A longitudinal flight dynamic study of a low mass moment of inertia vehicle is presented. Aerodynamic and stability derivatives of a flying-wing microaerial vehicle (FWMAV) were obtained through detailed subsonic wind tunnel tests at a Reynolds Number of 1.87 × 105. Rate and acceleration derivatives were obtained using the potential flow solver, Tornado®. A novel methodology for the estimation of dimensional derivatives is proposed, and results are compared with the conventional linear time-invariant systems (LTI) approach. Free response for natural frequency, damping coefficient, and time constant as well as forced response upon a unit step and a unit impulse elevon input has been calculated and analyzed. The proposed methodology predicted two pairs of complex conjugates for the longitudinal flight up to a pitch angle of 89° whereas the conventional methodology predicted the same up to 57°. Longitudinal modes sensitivity in terms of stability with the variation of mass, velocity, and pitch angle has also been analyzed. The flying-wing microaerial vehicle was able to sustain straight and level flight during flight trials; however, higher frequencies of phugoid and short period modes were observed. These high frequencies were the consequence of large magnitude of [Formula: see text] (ratio of Z-force derivative with the angle of attack and cruise velocity) and [Formula: see text] (ratio of Z-force derivative with the axial velocity and cruise velocity). It is concluded that the proposed methodology presented a more realistic representation of longitudinal flight modes since classical flight modes are captured till 89° which conventional LTI methodology failed to do so.

Longitudinal damping derivatives, [Formula: see text], of an aerial vehicle is important from an aerodynamic stability point of view. Experimental calculation of longitudinal damping derivatives using wind tunnel is not a cost-effective method; therefore, researchers have developed numerical solutions as an alternative. In this research, the longitudinal damping derivatives of a flying wing micro aerial vehicle (FWMAV) were calculated using numerical simulations by adopting pull-up maneuver and forced harmonic motion in pitch axis. Pull-up maneuver with four steady rotational rates was simulated to obtain pitch rate derivative, C mq. Combined derivative, [Formula: see text], was obtained by simulating forced harmonic motion of FWMAV around a mean angle of attack of 0° with amplitude of oscillation of ± 3° using four reduced frequencies (0.02, 0.03, 0.04, and 0.05). Unstructured surface and volume mesh was used in a spherical domain engulfed inside a large cuboid domain for moving reference frame strategy. Reynolds number taking mean aerodynamic chord as a reference length was 2.33 × 105. Spalart–Allmaras turbulence model was used. Pitch rate derivative, combined derivative, and acceleration derivative were found as − 0.03/rad, − 7.39/rad, and − 7.36/rad, respectively, by the use of a phase method at a reduced frequency of 0.03. During flight dynamic analysis, it was found that [Formula: see text] has a significant contribution on damping in short period mode with no effect on Phugoid mode. The research concluded that for tailless configurations, acceleration derivative [Formula: see text] can exist and can provide necessary damping in the longitudinal flight mode.

Purpose The purpose of this study is evaluate the optical properties of polyacrylonitrile (PAN) nanofibers containing fluorescent agents such as fluorescent dye and carbon quantum dots (CQDs) by using image-processing technique of Fluorescence microscope image. Design/methodology/approach The fluorescence microscope image of the pure PAN, PAN/CQDs and PAN/fluorescent dye nanofibers composite was analyzed using several image-processing techniques such as color histogram, lookup table (LUT), Fourier transform, RGB profile and surface plot analysis. Findings The fluorescence microscope image indicates that the fluorescence emission of nanocomposites depends on the type of fluorescent agent. The fluorescence intensity of nanofiber containing CQDs is more than nanofiber containing fluorescent dye. Various image-processing methods provide similar results for optical property of nanocomposites. Analyzing the LUT, the blue value of CQDs/PAN nanocomposite image was significantly higher than other nanocomposites. This was confirmed by other methods such as Fourier transform, color histogram and 3D topography of the electrospun nanofibers. According to analysis of colorimetric parameters, higher negative value of b* indicates bluer color for CQDs/PAN nanofibers than other nanocomposites. The obtained results indicate that the image-processing technique can be used to evaluate the optical property of fluorescent nanocomposite. Originality/value This study evaluates the optical properties of fluorescent nanocomposites by using image-processing techniques such as Fourier transform, color histogram, RGB profiles, LUT, surface plot and histogram analysis.

Purpose This work aims to study the effect of mordanting method as pre-mordanting (on-chrome), meta-mordanting (meta-chrome) and post-mordanting (after-chrome) on wool dyeing with madder natural dye without tannin and pomegranates peel, as a natural dye contains tannin. Design/methodology/approach The woolen yarn was dyed with madder and pomegranate peel natural dyes by three methods as pre-mordant, meta-mordant and pos-mordant. The color parameters and reflectance spectra of dyed samples were analyzed by using derivative spectroscopy and the principal component analysis (PCA) techniques. Findings The obtained results indicate that the color difference between the samples dyed with madder by pre-mordanting, and the samples dyed by other methods is more than the color difference between the samples dyed by meta-mordanting and post-mordanting. However, the color difference between samples dyed with pomegranate peel by pre-mordanting and meta-mordanting methods is less compared to other pairs. Also, analysis of reflectance spectra and color depth (K/S) values indicate that the color depth of dyed sample with madder by pre-mordanting method is more than other dyeing methods. But, the color depth of sample dyed with pomegranate peel by post-mordanting method is less compared to other methods. The analysis of first-, second-, third- and fourth-order derivatives of reflectance spectra and the study of the first, second, third and fourth PCs of reflectance spectra indicate that the reflectance of dyed samples with madder and pomegranates peel depends on the mordanting method. Originality/value Evaluation of the effect of mordanting method on color and reflectance of wool dyed with madder and pomegranates peel natural dyes using derivative spectroscopy and the PCA techniques

Purpose This paper aims to investigate using scanner-based adaptive neuro-fuzzy inference system (ANFIS), artificial neural networks (ANNs) and polynomial regression methods for prediction of silver nanoparticles (AgNPs) and dye concentrations on AgNP-treated silk fabrics. Design/methodology/approach For estimation of the dye and AgNPs concentration using image processing, the silk fabrics were scanned under the condition of 200 pixels per inch. The red green blue (RGB) values of scanned images were obtained after applying the median filter. Then, the relationship between scanner RGB values and dye and AgNPs concentrations were obtained by using artificial intelligence methods such as ANFIS and ANNs. Findings The best result was achieved by the ANFIS system for calculation concentration of dye with 0.07% error and concentration of AgNPs with 0.008 (gr/l) error. The obtained results indicate that the performance of the ANFIS system method is better than the other methods. Originality/value Using a scanner-based artificial intelligence technique for prediction of nanosilver and dye content on silk fabric.

The research focuses on the design space optimisation of National Advisory Committee for Aeronautics (NACA) submerged inlets through the formulation of a hybrid data fusion methodology. Submerged inlets have drawn considerable attention owing to their potential for good on-design performance, for example during cruise flight conditions. However, complexities due to the geometrical topology and interactions among various design variables remain a challenge. This research enhances the current design knowledge of submerged inlets through the utilisation of data mining and Computational Fluid Dynamics (CFD) methodologies, focusing on design space optimisation. A two-pronged approach is employed where the first step encompasses a low-fidelity model through data mining and surrogate modelling to predict and optimise the design parameters, while the second step uses the Design of Experiments (DOE) approach based on the CFD results for the candidate design geometry to construct a surrogate model with high fidelity for design refinement. The feasibility of the proposed methodology is demonstrated for the optimisation of the total pressure recovery of a NACA submerged inlet for the subsonic flight regime. The proposed methodology is found to provide good agreement between the surrogate and CFD-based model and reduce the optimisation processing time by half in comparison with conventional (global-based) CFD optimisation approaches.

The design and development of high-strength and low-weight composite landing gear struts is still a challenge in today’s world. In this study, a selection methodology for fiber-reinforced composite material for retractable main landing gear struts for specified lightweight aircraft up to 1600 kg mass is proposed. Four different fiber-reinforced composite materials, two each from the glass-fiber and carbon-fiber families, including E-glass fiber/epoxy, S-glass fiber/epoxy, T300 carbon fiber/epoxy, and AS carbon fiber/epoxy, were considered for analysis. For the design and analysis of a main landing gear strut, maximum landing loads for one point and two point landing conditions were calculated using FAA FAR 23 airworthiness requirements. Materials were categorized based on their strength-to-weight ratio and the Tsai-Wu failure criterion. Landing gear struts meeting the Tsai-Wu failure criterion, and having a maximum strength-to-weight ratio, were then modeled for performance under a collision detection test. This research concludes that T300 carbon fibre/epoxy is a recommended material for the manufacture of landing gear struts for specified lightweight aircraft.

Introduction : Despite the applications and advantages of ionizing radiation; there are many radiation risks to biological systems that are necessary to be reduced as much as possible. The present study aimed to assess the radioprotective effect of nanoniosomes loaded by Mentha Pulegium essential oil (MPEO-N) as a natural antioxidant on human peripheral blood mononuclear cells (PBMCs). Materials and methods MPEO-N nanoparticles were prepared by the lipid thin-film hydration method, and its physicochemical characteristics were analyzed. PBMCs were then irradiated with X-ray using a 6 MV linear accelerator at radiation doses of 25 and 200 cGy in the presence of non-toxic concentrations of MPEO-N nanoparticles (IC10). After 48 and 72 h of incubation, the radioprotective effect was investigated by measuring survival, apoptosis, and necrosis of PBMCs, using MTT assay and flow cytometry analysis. Results The hydrodynamic diameter and zeta potential of nanoniosomes were 106.0 nm and − 15.2 mV, respectively. The mean survival percentage of PBMCs showed a significant increase only at a radiation dose of 200 cGy compared with the control group. The percentages of apoptosis and necrosis of cells in the presence of MPEO-N nanoparticles at both radiation doses and incubation periods (48 and 72 hours) demonstrated a significant reduction compared with the control. Conclusion MPEO-N nanoparticles as a natural antioxidant, exhibited a favorable radioprotective effect by a significant reduction in the percentage of apoptosis and necrosis of irradiated PBMCs.

Human leukocyte antigen (HLA-G) participates in immunosuppression and is useful for prenatal diagnostics. Isolation of fetal cells positive for HLA-G by HLA-G antibody conjugated nanoparticles from the cervix of pregnant women is the basis for non-invasive prenatal testing. Endocervical specimens are fixed in transport medium before isolation using antibody conjugated nanoparticles. Staining of HLA-G using MEM-G/9 antibody, however, is restricted to unfixed cells. We investigated the effect of several fixatives on the interaction of HLA-G with MEM-G/9 in the HLA-G-positive cell line, JEG-3. We investigated absolute methanol, 1:1 acetate buffer:methanol, Pap solution and paraformaldehyde. The effects of these fixatives were evaluated using immunofluorescence. We found no MEM-G/9 surface staining of methanol fixed cells. Approximately 40% of JEG-3 cells fixed with paraformaldehyde failed to stain. Nearly all cells were stained with MEM-G/9 following fixation with acetate buffer:methanol or Pap solution. Our findings indicate the importance of using an appropriate fixative for preserving HLA-G cell surface antigen for studies using the MEM-G/9 antibody.

Objective: The study objects at assessing and comparing the intensity of the effect of valproate (VPA) and levetiracetam (LV) on the bone mass in young adult epileptic patients while distinguishing their methylene tetra-hydro folate reductase (MTHFR) genotypes and correlating MTHFR polymorphism and antiepileptic drugs (AEDs) usage with the risk of development of osteoporosis. Methods: The study design was a comparative, prospective, and observational study. It was conducted at Princess Esra Hospital (PEH), Hyderabad and genotype testing was carried out at Salar-e-Millat Research lab (PEH). The consent was obtained from total 70 subjects, divided into three groups: Group 1: 18 patients receiving sodium VPA monotherapy Group 2: 17 patients receiving LV monotherapy Group 3: 35 healthy control subjects from general population. Patients of either gender within age group of 15–40 years, experiencing generalized tonic-clonic seizures or focal seizures, receiving the AED for duration of time ≥2 years were included in the study. Results: Our study showed significant correlation between the AEDs treatment and MTHFR polymorphism in predisposing osteoporosis. Conclusion: The variants of MTHFR gene (C677T) are prone to develop increased levels of homocysteine as a result of decreased activity of the enzyme in their bodies which are further increased in patients receiving AEDs. Monitoring of homocysteine levels in epileptic patients especially in the mutants of MTHFR gene along with their periodic testing of bone mineral density levels is recommended. Treatment for low folate and calcium levels is recommended in these patients to correct their deficiencies.

Tumor suppressor miRNAs, miR-15a and miR-16–1, with high-specificity and oncogenic targeting of Bcl-2, can target tumor tissues. Disadvantages of the clinical application of free miRNAs include poor cellular uptake and instability in plasma, which can be partially improved by using nanocarriers to deliver anti-cancer agents to the tumor cell. In this study, cationic niosomes were designed and optimized with the specific formulation. Then, the physical characteristics, the cytotoxicity, the impact of transfected miRNAs on the expression of the Bcl-2 gene, and the apoptosis rate of the different formulation into prostate cancer cell were determined. The optimum formulation containing tween-60: cholesterol: DOTAP: DSPE-PEG2000 at 70:30:25:5 demonstrated that the vesicle size and zeta potentials were 69.7 nm and + 14.83 mV, respectively. Additionally, noisome-loaded miRNAs had higher toxicity against cancer cells comparing with free forms. The transfection of PC3 cells with the combination therapy of nanocarriers loaded of two miRNAs led to a significant decrease in the expression of the Bcl-2 gene and increased the degree of cell death in PC3 cells compared with other treatment groups, and the synergistic effects of co-delivery of miR-15a and miR-16–1 on prostate cancer cells were shown. According to the results, it seems the designed niosomes containing miR-15a and miR-16–1 can target the Bcl-2 gene and provide a cheap, applicable, cost-effective, and safe drug delivery system against prostate cancer.

The development of an effective and noninvasive early method for obtaining fetal cells is crucial to prenatal screening. Despite proving the presence of fetal cells in the reproductive tract, their use is limited due to their inability to properly isolate them from maternal cells. Magnetic-activated cell sorting (MACS) is a simple technique to separate cells. The present study aimed to develop a MACS-based platform for the isolation of the HLA-G expressing trophoblast cells. For this purpose, first, the triazine functionalized MNPs were synthesized and characterized. Then, MNPs were directly and indirectly conjugated by the MEM-G/9 antibodies targeting HLA-G+ cells. The antibody amount on the surface of the nanoparticles was determined with the Bradford assay. The cell capture efficiency was also investigated. Various characterization methods confirmed the successful nanoparticle synthesis and antibody conjugation. The optimal initial antibody amount for the immobilization was about 20 μg and the optimal time was 3 h. The antibody-nanoparticles by the indirect method had better targeting and capture efficiency than the direct method. The MNPs indirectly conjugated with antibodies are an efficient tool for cell isolation and present considerable potential to be applied in biomedical fields.

A comprehensive design cycle of a nose landing gear strut having an oleo-pneumatic shock absorber for a lightweight aircraft is proposed. Design and analysis of a retractable nose landing gear according to Airworthiness Standards FAA FAR Part 23 have been carried out. This research is focused on mathematical modeling of an oleo-pneumatic strut with an analytical solution of design variables at static and dynamic loading conditions. The variation of spring and damping characteristics of an oleo-pneumatic shock absorber with the stroke length is also presented. Feasibility of equivalent mechanical spring and damper along with comparison of pneumatic as air spring and oleo as hydraulic damper is studied. Numerical integration technique was used to solve the dynamic model of an oleo-pneumatic strut with forcing function of an impact force during touch down scenario. Energy conservation principle was used to determine height required for drop tests. Parametric study of anteversion angle within the constraints of ground clearance and volume in the fuselage determined an optimized angle of nose landing gear strut. Based on the maximum pressure and impact force encountered during landing, the hydraulic cylinder and piston design was finalized. In order to validate the proposed design cycle for preliminary phase, a structural integrity of cylinder and piston assembly was carried out using finite element analysis. Deformation, maximum stresses and factor of safety validated the proposed design cycle of a nose landing gear strut specific to a general aviation aircraft having all up mass of 1600 Kg.

BACKGROUND: The present study aimed to investigate the one-year prevalence of SARS-CoV-2, common comorbidities and demographic information among negative- and positive rRT-PCR in health care workers (HCW), hospitalized and outpatients. Also, the association between SARS-CoV-2 cycle threshold (Ct) and the outcomes of patients were analyzed in Babol, northern Iran. METHODS: This large retrospective cross-sectional study was performed between March 2020 and March 2021. The records of 19232 hospitalized, outpatients and HCW suspected to COVID-19 were collected from teaching hospitals in the North of Iran. RESULTS: Out of the 19232 suspected to COVID-19 patients, 7251 (37.7%) had a positive rRT-PCR result; 652 (9%), 4599 (63.4%) and 2000 (27.6%) of those were categorized as HCW, hospitalized and outpatients, respectively. Moreover, between the hospitalized and the outpatient group, 10.2 and 0.8% cases died, whereas no death cases were reported in the HCW. Furthermore, it seems that death rate was significantly different between the three groups of Ct value, the highest mortality in those with Ct between 21 and 30 (group B=7.6%) and the lowest in the group with the highest Ct (between 31 and 40 = 5.5%) (p

Workplace stressors and stress play a pivotal role in shaping an individual's consumption behavior, but its implication, particularly in consumer psychology, remains nascent. This study, grounding on the theory of social conformity and compliance and the theory of reasoned action, addresses the impact of chronic workplace stressors on impulsive buying behavior through the mechanism of stress in the presence of emotional intelligence. For this purpose, a total of 230 respondents were engaged using a questionnaire. Based on a Structural equation modeling study found that Emotional intelligence plays a major part in shaping consumers' buying behavior and develops theoretical linkages of a previously neglected area. Both WB and WD have a positive impact on the stress and are significant at 0.001. To reduce stress, workplace stressors control the emotions of people and compel them for impulsive buying disorders. From discussed practical implications, managers can better use the results by designing their products to make them more appealing to customers' impulses.