In this article, Smooth Super-twisting Sliding Mode Control (SSTWSMC) is investigated for the class of underactuated system. In underactuated systems, the control design is not directly applicable as ...for other systems (known as fully actuated systems). Therefore, at initial step, a nonlinear uncertain model of systems is transformed into the controllable canonical form, and then Smooth Super Twisting (SSTW) based Sliding Mode Control (SMC) is devised for the control design purpose for the considered class. In addition, closed loop stability of the proposed technique is presented in a fascinating way. The effectiveness and supremacy of the proposed control technique is proven by extensive analysis between conventional Sliding Mode Control (SMC), Super twisting (STW) sliding mode control and Smooth Super-twisting Sliding Mode Control (SSTWSMC). The comprehensive analysis evaluates the attributes like robustness enhancement, settling time, control effort, chattering reduction, overshoot, sliding mode convergence, etc. and is supported by simulations as well as practical implementation on ball and beam balancer (which is considered as application example).
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract
Background
Inadvertent delays in access to appropriate therapeutic interventions in high-risk group coronavirus disease 2019 (COVID-19) patients contribute to mortality in patients with ...severe/critical disease presentation.
Objectives
The aim of this study was to determine the effect of timely admission to the hospital on mortality of patients with severe/critical COVID-19. Another secondary aspect of this study was to observe the efficacy of time-dependent use of corticosteroids on mortality of critical/severe COVID-19 patients.
Methods
Clinical data of 659 patients with severe/critical COVID-19, admitted to four major tertiary care hospitals from the Islamabad-Rawalpindi region of Pakistan was retrospectively collected from a period February–August 2020. Multivariate logistic regression analysis was carried out to determine the predictors of mortality in severe/critical COVID-19 patients.
Results
Out of a total of 659 patients, 469 (71.2%) patients died. Age > 60 years, presence of hypertension, heart disease and kidney disease along with late admission (>5 days) were significant predictors of mortality in patients with severe/critical COVID-19.
Conclusions
The study highlights the importance of well-timed provision of appropriate medical interventions control COVID-19-associated mortality.
Background: The treatment of infected root canals is one of the most essential areas in dentistry. The endodontic therapy comprises of a sequence of steps that includes the purging of disease and ...infectious tissues from the root canal system. The objective of the study is to compare the effect of an experimental herbal root canal irrigant (Sapindus mukorossi) and Ethylenediaminetetraacetic acid, on the micro hardness of human dentin. Methods: Ninety single rooted teeth were collected displayed intact external morphology the selected teeth were than divided randomly into 3 groups (n=30); 1 control and 2 experimental groups: Group A consisted of specimen treated with Ethanolic extract of Sapindus mukorossi. Group B consisted of specimen treated with 17% Ethylenediaminetetraacetic acid and Group C (control group) consisted of specimen of roots were sectioned immersed in distilled water. After the removal of crowns, the roots were sectioned embedded in the polymer resin leaving the root dentine exposed, the micro hardness was determined. Then, the samples from each group were treated with respective irrigant solution for 15 minutes and then observation regarding the micro hardness were noted again by using Vickers micro hardness tester. Analysis of data were obtained by application of Wilcoxon signed rank test. Results: The study revealed that there was no significant difference noted in dentin microhardness of group “A” sample after dipping in experimental irrigant solution (Sapindus mukorossi). However, the study found significant difference in context of decrease in dentin microhardness after dipping a sample in a group “B” irrigant solution (17% Ethylenediaminetetraacetic acid). Conclusion: In order to preserve the strength of dentin that will ultimately be beneficial for increase in survival of teeth in function, probably the herbal extract of Sapindus mukorossi would be better candidate for future endeavour and presented as an economic and effective alternative amongst root canal irrigants.
Bovine serum albumin (BSA) is usually employed as a model protein because of being homologous with human serum albumin. Cysteine-34 of BSA has been oxidised with Ellman's reagent to produce BSA ...labelled with an Ellman's moiety (BSA-SE). The BSA-SE was then reacted with glutathione, N-acetylcysteine and D-penicillamine (D-pen). The two were able to release the Ellman's moiety bound at cysteine-34 while D-pen did not. Albumin labeled using Ellman's reagent was used to demonstrate the cleavage of a protein mixed disulphide. The kinetics of thiol disulfide interchange reactions involving formation of a chromophoric thiolate were determined by UV-visible spectroscopy. The reaction of thiolates with excess Ellman's reagent is used for quantitative estimation of thiol by measuring the absorption at λ, 412 nm. The disulfide exchange reactions occurring at Cys-34 of BSA was determined and the reduction of oxidized Cys-34 was studied in order to understand the reverse reaction. Spectroscopic evidence suggested that glutathione and N-acetylcysteine remove the label and produce BSA in a disulfide form. In contrast, D-pen reaction returned BSA to its thiolate form via mediation. It was observed that thio-disulfide exchange occurred at cysteine-34 labelled with Ellman's moiety. The implications to the redox status of plasma are discussed.
Objective: To compare mean hematocrit levels in patients with uncomplicated and complicated Dengue Fever and evaluate the role of hematocrit in differentiating uncomplicated and complicated Dengue ...Fever.
Study Designs: Prospective longitudinal study.
Place and Duration of Study: Department of Infectious Diseases, Holy Family Hospital, Rawalpindi Pakistan, from Oct 2019 to Sep 2020.
Methodology: Around 240 dengue patients were enrolled. Hematocrit level at presentation was measured using an automated haematology analyzer. The patients were then followed for the development of complications (Dengue hemorrhagic fever and Dengue shock syndrome).
Results: Of 240 patients, 183(76.2%) were male, and 57(23.8%) were female. Dengue Fever was present in 96(40%) patients, whereas 144(60%) patients developed complications (Dengue Hemorrhagic Fever and Dengue Shock Syndrome). The mean hematocrit level at presentation significantly differed among the groups (p=0.012). Following the ROC curve analysis, for the cut-off value of 42.6% of hematocrit Group II had a sensitivity of 56.25% and a specificity of 62.5% at an Area under the curve of 0.589.
Conclusion: The mean hematocrit levels were significantly higher in patients with complicated versus uncomplicated Dengue Fever. Hematocrit could not be projected as a predictor of Dengue Fever severity.
Background and objective Blood gas analysis plays a pivotal role in the management of various respiratory and metabolic disorders. Both arterial and venous samples can be used for blood gas analysis. ...Arterial blood sampling is technically difficult and is associated with more complications as compared to venous sampling. Many studies have shown the correlation of arterial and venous pH and bicarbonate levels in sepsis, diabetic ketoacidosis (DKA), chronic obstructive pulmonary disease (COPD), and circulatory failure. But, there is a paucity of data, pertaining specifically to the correlation of arterial blood gas (ABG) analysis and venous blood gas (VBG) analysis in patients with renal failure. The objective of this study was to look for any possible correlation between arterial and venous pH and bicarbonate values in patients with renal failure. Methods This cross-sectional study was carried out at a large tertiary care hospital in Rawalpindi, Pakistan. Over a period of eight months, 101 patients with renal failure were enrolled after obtaining informed consent. Arterial and venous samples from the patients were obtained, analyzed, and compared. Results Out of the total 101 patients, 53 (52.5%) were male while 48 (47.5%) were female. The mean age of the patients was 46.23 ±15.54 years. Mean arterial pH and venous pH were 7.35 and 7.28 respectively. The Pearson correlation coefficient between arterial and venous pH was found to be 0.857 (p<0.001). The mean arterial and venous bicarbonate values were 14.47 mEq/L and 15.51 mEq/L respectively. And the Pearson correlation coefficient between arterial and venous bicarbonate was found to be 0.842 (p<0.001). Conclusion Venous pH and bicarbonate levels correlate strongly with arterial pH and bicarbonate levels, respectively, in patients with renal failure.
Background Because of the anatomical properties of the inferior calyx, lower pole stones are difficult to remove through the ureter, even if the stones are fragmented. Retrograde intra-renal surgery ...(RIRS) is typically employed to treat the smaller lower pole stones (1.0-2.0 cm) while percutaneous nephrolithotomy (PCNL) is primarily used to treat the larger diameter stones or when RIRS has failed to clear the stones. This study was conducted to compare mini-PCNL and RIRS for the management of lower pole kidney stones in terms of stone clearance. Material and methods This randomized control trial was conducted in the Department of Urology, Shaikh Zayed Hospital, Lahore from October 2020 to December 2022. A total of 150 patients between the ages of 18 and 80 years with a kidney stone size of 10-20 mm at the lower pole were included. Patients with positive urine culture, anatomical abnormalities, uncontrolled diabetes (hemoglobin{Hb}A1c >9%), and undergone previous renal surgery were excluded. Group A patients were treated with mini-PCNL, while group B patients were managed with RIRS. Follow-up visits were planned four weeks postoperatively with CT KUB (computed tomography of kidneys, ureters, and bladder) plain to assess stone clearance. Results The mean age in group A was 43.27 ± 13.86 years, while in group B was 45.32 ± 14.14 years. Out of 150 patients, 102 (68.0%) were males and 48 (32.0%) were females. Mean size of the stone was 15.30 ± 2.21 mm. Stone clearance after mini-PCNL was found in 69 (92.0%) patients and after RIRS in 59 (78.67%) patients (p-value = 0.021). Mean hospital stay after RIRS was 1.1 ± 0.09 days, while it was 2.3 ± 0.64 days after mini-PCNL (p-value < 0.001). Two (2.67%) patients in the mini-PCNL group developed bleeding postoperatively. The stone clearance rate in older patients (51 to 80 years) was significantly higher in the mini-PCNL group than RIRS group. Similarly, the stone clearance rate in female patients and in patients with larger stones (16 to 20 mm) was found to be higher in mini-PCNL group as compared to the RIRS group. Conclusion This study concluded that both mini-PCNL and RIRS are safe and efficient techniques for treating lower pole kidney stones with a size of 11-15 mm. However, mini-PCNL has a higher stone clearance rate compared to RIRS in the treatment of stones larger than 15 mm in size. This study further suggested that patients treated with mini-PCNL had a longer hospital stay compared to patients treated with RIRS.
COVID-19 became a pandemic rapidly after its emergence in December 2019. It belongs to the coronavirus family of viruses, which have struck a few times before in history. Data based on previous ...research regarding etiology and epidemiology of other viruses from this family helped played a vital role in formulating prevention and precaution strategies during the initial stages of this pandemic. Data related to COVID-19 in Pakistan were not initially documented on a large scale. In addition, due to a weak health care system and low economic conditions, Pakistan's population, in general, already suffers from many comorbidities, which can severely affect the outcome of patients infected with COVID-19.
COVID-19 infections are coupled with a manifestation of various notable outcomes that can be documented and characterized clinically. The aim of this study was to examine these clinical manifestations, which can serve as indicators for early detection as well as severity prognosis for COVID-19 infections, especially in high-risk groups.
A retrospective observational study involving abstraction of demographic features, presenting symptoms, and adverse clinical outcomes for 1812 patients with COVID-19 was conducted. Patients were admitted to the four major hospitals in the Rawalpindi-Islamabad region of Pakistan, and the study was conducted from February to August 2020. Multivariate regression analysis was carried out to identify significant indicators of COVID-19 severity, intensive care unit (ICU) admission, ventilator aid, and mortality. The study not only relates COVID-19 infection with comorbidities, but also examines other related factors, such as age and gender.
This study identified fever (1592/1812, 87.9%), cough (1433/1812, 79.1%), and shortness of breath (998/1812, 55.1%) at the time of hospital admission as the most prevalent symptoms for patients with COVID-19. These symptoms were common but not conclusive of the outcome of infection. Out of 1812 patients, 24.4% (n=443) required ICU admission and 21.5% (n=390) required ventilator aid at some point of disease progression during their stay at the hospital; 25.9% (n=469) of the patients died. Further analysis revealed the relationship of the presented symptoms and comorbidities with the progression of disease severity in these patients. Older adult patients with comorbidities, such as hypertension, diabetes, chronic kidney disease, and asthma, were significantly affected in higher proportions, resulting in requirement of ICU admission and ventilator aid in some cases and, in many cases, even mortality.
Older adult patients with comorbidities, such as hypertension, diabetes, asthma, chronic obstructive pulmonary disorder, and chronic kidney disease, are at increased risk of developing severe COVID-19 infections, with an increased likelihood of adverse clinical outcomes.
Objective: To evaluate the severity of depression and anxiety among caregivers of children having cerebral palsy and correlate severity with the type of cerebral palsy and functional capability of ...the child.
Study Design: A cross-sectional study.
Place and Duration of Study: Department of Psychiatry and Rehabilitation Medicine, Combined Military Hospital, Gujranwala, from Oct 2015 to Aug 2018.
Methodology: Through consecutive sampling, 186 caregivers diagnosed with anxiety and/or depression based on the diagnostic criteria of International Classification of Diseases version 10, and their cerebral palsy children were recruited. Symptom severity was assessed using Beck Depressive Inventory for depression and Beck Anxiety Inventory for anxiety. The functional capabilities of the children were assessed through gross motor function classification system (GMFCS). For correlation, Pearson’s chi square test was used using SPSS version 20.
Results: The mean age was 30 ± 3.3 years. Fourteen (7.5%) were fathers of cerebral palsy children and 172 (92.5%) were mothers of cerebral palsy children. Majority of the cerebral palsy children 74 (39.8%) had spastic diplegia and the functional level I of gross motor function classification system 53 (28.5%). Most of the caregivers had mild anxiety and minimal depression (33.9% and 38.7% respectively). Significant correlation existed among the gross motor functional capability and the level of anxiety but not with depression (p<0.01 and p=0.155 respectively). No statistical association was found between the type of cerebral palsy and the level of anxiety or depression (p=0.240 and p=0.102 respectively).
Conclusion: Most caregivers in our study had mild anxiety and minimal depression...
Objective: To identify depression and cognitive impairment after stroke and analyze association with age, gender, stroke location, and social support.
Study Design: A cross-sectional analytical ...study.
Place and Duration of Study: Psychiatry and Rehabilitation Medicine, Combined Military Hospital Gujranwala, from Oct 2015 to Aug 2018.
Methodology: Patients (age: 20-80 years) with stroke ≥3 months were included. Those with aphasia, unstable medical history, and coexisting other neurological disorder were excluded. Cognition was assessed by Montreal Cognitive Assessment (MoCA) and post-stroke depression (PSD) was assessed by Beck Depressive Inventory 2nd Edition (BDI-II).
Results: Out of 76 patients (meanage: 59 ± 7 years), 53 (69.7%) were male and 23 (30.3%) were females. Fifty-five (72.4%) were of age >55 years and 58 (76.3%) patients had social support. On MoCA evaluation, 41 (53.9%) patients had cognitive impairment. BDI-II assessment showed that 43 (56.6%) individuals had depression. A significantly higher percentage of males, patients without social support, and patients >55 years developed PSD with p<0.05. The cognitive deficit, was statistically significant in the age group of >55 years (p=0.026) and no correlation with gender or presence/absence of social support was observed (p=0.088 and p=0.485 respectively). Similarly, no significant correlation was found between stroke location and development of cognitive deficit or PSD (p=0.361 and p=0.390 respectively).
Conclusion: Cognitive impairment and PSD were frequently present after stroke. PSD was more common in males, patients without social support, and patients of older age while cognitive deficit was more common in older age.
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