Comparison of characteristics and ventilatory course between coronavirus disease 2019 and Middle East respiratory syndrome patients with acute respiratory distress syndrome

Imran Khalid,Romaysaa M Yamani,Maryam Imran,Muhammad Ali Akhtar,Manahil Imran,Rumaan Gul,Tabindeh Jabeen Khalid,Ghassan Y Wali 대한중환자의학회 2021 Acute and Critical Care Vol.36 No.3

Background: Both coronavirus disease 2019 (COVID-19) and Middle East respiratory syndrome (MERS) can cause acute respiratory distress syndrome (ARDS); however, their ARDS course and characteristics have not been compared, which we evaluate in our study. Methods: MERS patients with ARDS seen during the 2014 outbreak and COVID-19 patients with ARDS admitted between March and December 2020 in our hospital were included, and their clinical characteristics, ventilatory course, and outcomes were compared. Results: Forty-nine and 14 patients met the inclusion criteria for ARDS in the COVID-19 and MERS groups, respectively. Both groups had a median of four comorbidities with high Charlson comorbidity index value of 5 points (P>0.22). COVID-19 patients were older, obese, had significantly higher initial C-reactive protein (CRP), more likely to get trial of high-flow oxygen, and had delayed intubation (P≤0.04). The postintubation course was similar between the groups. Patients in both groups experienced a prolonged duration of mechanical ventilation, and majority received paralytics, dialysis, and vasopressor agents (P>0.28). The respiratory and ventilatory parameters after intubation (including tidal volume, fraction of inspired oxygen, peak and plateau pressures) and their progression over 3 weeks were similar (P>0.05). Rates of mortality in the ICU (53% vs. 64%) and hospital (59% vs. 64%) among COVID-19 and MERS patients (P≥0.54) were very high. Conclusions: Despite some distinctive differences between COVID-19 and MERS patients prior to intubation, the respiratory and ventilatory parameters postintubation were not different. The higher initial CRP level in COVID-19 patients may explain the steroid responsiveness in this population.

Biologically Inspired Dynamic Soaring Maneuvers for an Unmanned Air Vehicle Capable of Sweep Morphing

Imran Mir,Adnan Maqsood,Suhail Akhtar 한국항공우주학회 2018 International Journal of Aeronautical and Space Sc Vol.19 No.4

Dynamic soaring is a versatile maneuver executed to acquire energy available in the atmospheric wind shears. In this paper, an innovative concept of integrating wing sweep morphing during dynamic soaring maneuver is proposed. An unmanned air vehicle (UAV) with standard wing–tail configuration is considered. The aerodynamic modeling is based on the empirical estimation procedure duly validated with numerical vortex lattice method (VLM). The dynamics of the UAV is modeled as a three-dimensional point-mass model with nonlinear wind shear. The trajectory optimization problem is formulated as an optimal control problem using Guass pseudospectral method. The comparison of wing sweep morphing ability during flight is compared with its fixed-wing counterpart. Typical performance parameters used for comparison between both configurations include minimum wind shear and aerodynamic efficiency. Results indicate significant reduction in the minimum wind shear requirement (24%) and considerable improvement in the aerodynamic efficiency (24% drag reduction, 10% less lift coefficient requirement, 34% higher normalized energy and 25% improved loitering performance). A great potential of further exploring and coupling different wing-morphing mechanisms to further extract potential benefits of dynamic soaring maneuvers is proposed. This investigation will serve as a baseline for the proof of concept that dynamic soaring can be extended to a morphing platform in achieving optimal performance.

Effects of peripartal glucose precursor supplementation on lactation performance and metabolic health of primiparous and multiparous dairy cows

Akhtar Muhammad Uzair,Hifzulrahman,Pasha Talat Naseer,Avais Muhammad,Khan Nauman,Chishti Ghazanfar Ali,Ali Mubashar,Imran Muhammad,Tahir Muhammad Naeem,Naveed-ul-Haque Muhammad 아세아·태평양축산학회 2023 Animal Bioscience Vol.36 No.6

Objective: Hyperketonemia remains a major metabolic issue of serious milk production and a major health concern in early lactation cows. Oral supplementation of glucose precursors (GP) can be used to prevent hyperketonemia in dairy cows. The objective of this study was to compare the beneficial effects of orally supplementing a mixture of GP on metabolic health indicators and milk production status of primiparous (PP) and multiparous (MP) dairy cows. Methods: Twenty-eight Holstein cows were blocked by expected date of parturition, previous lactation yield, and parity. The cows were randomly allocated to one of the four treatment groups (n = 7 cows/group) based on their parity and GP supplementation: i) PP cows fed basal diet only (PP-CON), ii) PP cows with oral supplementation of GP (PP-GP), iii) MP cows fed basal diet only (MP-CON), and iv) MP cows with oral supplementation of GP (MP-GP). Glucose precursor (glycoline liquid) was orally drenched (300 mL/d) in GP cows from 7 days prepartum through 7 days postpartum. Other than GP supplementation, all cows were fed similar pre- and postpartum basal diets. Results: In both pre- and postpartum periods, serum glucose concentration was increased, whereas β-hydroxybutyrate and free fatty acids were decreased in GP cows compared with the CON cows. Milk yield and milk components were statistically not different between GP and CON cows over the first 9 week of lactation. The yield of actual milk, energycorrected milk, 63-days cumulative milk, colostrum yield, and calf birth weight remained higher in MP cows compared with PP cows. Conclusion: Oral drenching of GP around calving can be recommended to successfully improve the metabolic health and reduce the negative effects of hyperketonemia not only in MP but also in PP dairy cows.

Application of modified cloud point extraction method for the chromium speciation in artificial saliva extracts of different snuff products

Asma Akhtar,Tasneem Gul Kazi,Hassan Imran Afridi,Mustafa Khan,Muhammad Bilal,Noman Khan 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.59 No.-

A modified cloud point extraction method (m-CPE) was developed for the speciation of chromium species (Cr3+ and Cr6+) in artificial saliva extracts (ASE) of snuff products. In this method, Cr3+ was complexed with 8-hydroxyquinoline, which was trapped in nonionic surfactant (Triton X-114), prior to analyzed by electrothermal atomic absorption spectrometer (ETAAS). Whereas, the total extractable Cr was determined by reducing Cr6+ to Cr3+ using Na2SO3 as a reducing reagent. Several parameters were optimized for the developed m-CPE. Under the most favorable conditions, enrichment factor, enhancement factor and limit of detection for the proposed method were 60, 134 and 0.04 μg L−1, respectively having relative standard deviation <5%. Health risks associated with the intake of total Cr in snuff products was also assessed. Estimated daily intake of Cr via sniffing 10 g/day of dry and moist snuff products was found below the maximum tolerable daily intake whereas the calculated risk for cancer due to Cr was observed in the acceptable range of 10 E−6–E−4.

Effect of Peritectic Banded Structure on Magnetic Properties of SmCo<SUB>5</SUB> Sintered Magnets

Saleem Akhtar,A. Nusair Khan,Mushtaq Khan,Syed Husain Imran Jaffery,Arslan Saleem 한국자기학회 2020 Journal of Magnetics Vol.25 No.4

SmCo5 is well known for its high coercivity. However, still room is available to increase the coercive power of SmCo5, since the theoretical values of the compound is far higher than the achieved values. Different attempts, in this regard, have been made either by controlling the microstructure or the chemical composition. However, it is noted that no or very few literature is available regarding the control of microstructure through solidification. Three types of SmCo5 compound were prepared through induction melting technique so that final solidification be manipulated by controlling the mold temperature. Fractrographic analysis revealed a unique peritectic structure in SmCo5 compound. It was observed that the peritectic plates, having nano-size thickness, remain present even after high temperature sintering operation. The nano-scale peritectic plates may affect the final magnetic properties, especially the coercivity of the subject compound.

Veiled courage: Inside the women’s resistance against violence through their writings

Muhammad Imran,Yuee Chen,Xiaofei Matthew Wei,Samina Akhtar 이화여자대학교 아시아여성학센터 2020 Asian Journal of Women's Studies(AJWS) Vol.26 No.1

This article focuses on Afghan women’s courage in resisting physical and other violence and victimization through their writings. It argues that the absence of a strong Afghan female voice has led numerous female writers to highlight women’s issues in Afghanistan. It demonstrates the courage and gradual awakening of women in Afghanistan to fight against violence and victimization in a culturally complex and patriarchal society. Thus, this is an appraisal of their struggle and highlights women’s issues in order to spread awareness about gaining a voice by women being vital for survival.

H∞ Control Problem of Discrete 2-D Switched Mixed Delayed Systems Using the Improved Lyapunov-Krasovskii Functional

Zhaoxia Duan,Imran Ghous,Yuanqing Xia,Jahanzeb Akhtar 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.8

This paper deals with the problem of exponential stability and H∞ control of two-dimensional (2-D) switched discrete systems with mixed time-varying delays. Firstly, this work suggests some improvements to Lyapunov-Krasovskii functional (LKF) discussed in the previous literature. Such improvements have been achieved by introducing some new terms containing the summations of state vector in single and double forms in an effort to capture the extra information related to time delays. Secondly, delay-dependent conditions based on the improved LKF are derived for the exponential stability and H∞ performance of 2-D switched systems in the form of linear matrix inequalities (LMIs) by virtue of the average dwell time approach. Thirdly, a state-feedback controller is designed to ensure the exponential stability of the overall closed-loop system under consideration with a desirable H∞ disturbance attenuation level γ. Finally, a suitable example is provided which highlights the benefits of the proposed results by comparing them with the results available in literature both in terms of conservativeness and computational burden.

Pressure mode decomposition analysis of the flow past a cross-flow oscillating circular cylinder

Muhammad Sufyan,Hamayun Farooq,Imran Akhtar,Zafar Bangash 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.1

Proper orthogonal decomposition (POD) is often employed in developing reduced-order models (ROM) in fluid flows for design, control, and optimization. Contrary to the usual practice where velocity field is the focus, we apply the POD analysis on the pressure field data obtained from numerical simulations of the flow past stationary and oscillating cylinders. Since pressure mainly contributes to the hydrodynamic forces acting on the structure, we compute the pressure POD modes on the cylinder surface oscillating in lock-in and lock-out regions. These modes are then dissected into sine and cosine magnitudes to estimate their contribution in the development of pressure lift and drag decomposition coefficients, respectively. The key finding of this study is that more POD modes are required to capture the flow physics in nonsynchronous regimes as compared to synchronization case. Engineering application of this study is the development of reduced-order models for effective control techniques.

Diversity in Betasatellites Associated with Cotton Leaf Curl Disease During Source-To-Sink Movement Through a Resistant Host

Khan, Iftikhar Ali,Akhtar, Khalid Pervaiz,Akbar, Fazal,Hassan, Ishtiaq,Amin, Imran,Saeed, Muhammad,Mansoor, Shahid The Korean Society of Plant Pathology 2016 Plant Pathology Journal Vol.32 No.1

Cotton leaf curl is devastating disease of cotton characterized by leaf curling, vein darkening and enations. The disease symptoms are induced by DNA satellite known as Cotton leaf curl Multan betasatellite (CLCuMuB), dominant betasatellite in cotton but another betasatellite known as Chili leaf curl betasatellite (ChLCB) is also found associated with the disease. Grafting experiment was performed to determine if host plant resistance is determinant of dominant population of betasatellite in cotton (several distinct strains of CLCuMuB are associated with the disease). Infected scion of Gossypium hirsutum collected from field (the source) was grafted on G. arboreum, a diploid cotton species, resistant to the disease. A healthy scion of G. hirsutum (sink) was grafted at the top of G. arboreum to determine the movement of virus/betasatellite to upper susceptible scion of G. hirsutum. Symptoms of disease appeared in the upper scion and presence of virus/betasatellite in the upper scion was confirmed via molecular techniques, showing that virus/betasatellite was able to move to upper scion through resistant G. arboreum. However, no symptoms appeared on G. arboreum. Betasatelites were cloned and sequenced from lower scion, upper scion and G. arboreum which show that the lower scion contained both CLCuMuB and ChLCB, however only ChLCB was found in G. arboreum. The upper scion contained CLCuMuB with a deletion of 78 nucleotides (nt) in the non-coding region between Arich sequence and ${\beta}C1$ gene and insertion of 27 nt in the middle of ${\beta}C1$ ORF. This study may help in investigating molecular basis of resistance in G. arboreum.

Modeling and simulation of planar SOFC to study the electrochemical properties

Jawad Hussain,Rashid Ali,Majid Niaz Akhtar,Mujtaba Hussain Jaffery,Imran Shakir,Rizwan Raza 한국물리학회 2020 Current Applied Physics Vol.20 No.5

In this paper, modeling and simulations are carried out using COMSOL Multiphysics. A three-dimensional model is developed for a planar intermediate temperature (IT) solid oxide fuel cell (SOFC). A parametric study has been carried out to analyze the performance of SOFC. Simulations reveal some promising features and enhanced performance of SOFC. It is shown that the maximum value of power (4–3.3) kW/m2 still remains higher with significant rise of temperature (600 °C–1000 °C), nearly 0.15 kW/m2 is the very small loss of power per 100 °C rise of temperature. Results have shown that the electrolytic current density is (6700–5500) A/m2 for peak value of power (4–3.3) kW/m2 with increase of temperature (600 °C–1000 °C). For model validation we have plotted a comparison of average current density.