University of Sindh
  • Jamshoro, Sindh, Pakistan
Recent publications
bold xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Background: The usability of university websites is important to ascertain that they serve their intended purpose. Their usability can be evaluated either by testing methods that rely on actual users or by inspection methods that rely on experts for evaluation. Heuristic evaluation and guideline reviews are two inspection methods of usability evaluation. A heuristic evaluation consists of a few general heuristics (rules), which are limited to checking general flaws in the design. A guideline review uses a much larger set of guidelines/suggestions that fit a specific business domain. Literature review: Most of the literature has equated usability studies with testing methods and has given less focus to inspection methods. Moreover, those studies have examined usability in a general sense and not in domain- and culture-specific contexts. Research questions: 1. Do domain- and culture-specific heuristic evaluation and guideline reviews work similarly in evaluating the usability of applications? 2. Which of these methods is better in terms of the nature of evaluation, time needed for evaluation, evaluation procedure, templates adopted, and evaluation results? 3. Which method is better in terms of thoroughness and reliability? Research methodology : This study uses a comparative methodology. The two inspection methods—guideline reviews and heuristic evaluation—are compared in a domain- and the culture-specific context in terms of the nature, time required, approach, templates, and results. Results: The results reflect that both methods identify similar usability issues; however, they differ in terms of the nature, time duration, evaluation procedure, templates, and results of the evaluation. Conclusion: This study contributes by providing insights for practitioners and researchers about the choice of an evaluation method for domain- and culture-specific evaluation of university websites.
The two-dimensional laminar boundary layer flow and heat characteristics of silver (Ag) water based nanofluid with buoyancy effect over porous shrinking/stretching sheet has been considered. The shooting technique is used for numerical solutions to address the considered physical flow parameters. The numerical investigation shows that the triple solutions exists at the distinct ranges of parameters. Therefore, the analysis of stability is carried out to explore the reliability of solutions. The important results related to the stable solutions indicate that the skin friction declines for λ>0 and enhances for λ<0 when suction, and nanoparticles volume fractions are enhanced. An increase in rate of suction decreases velocity and the temperature profiles. Besides, an increase in silver nanoparticles volume fraction increases velocity and the temperature profiles, respectively. An augmentation in thermal slip factor reduced the temperature. The decrement in heat sink/source constraint resulted the lower temperature.
To study the effects of sex ratio differences on the growth and ovarian development of Exopalaemon carinicauda, and their mechanism, we cultured female shrimps with different numbers of males for five weeks, and measured the growth and ovarian development index of relevant individuals. The results show that: 1) the existence of males reduced the growth rate of females, but significantly improved the ovarian development rate of female individuals. The growth rate of females living with the same sex was significantly accelerated, but their ovarian development rates were relatively slow. 2) Four kinds of communication modes between females and males were tested; i.e., free contact, chemical signals, visual signals, and coexisting chemical and visual signals. Of these four types, free contact improved the ovarian development of females. Under the condition of free contact, the period of the ovarian development cycle was shortened, more nutrients accumulated in the ovary, the amount of sex hormones and Vitellogenin (Vg) increased, and the expression of the gonad-inhibitory hormone (gih) gene tended to decrease. We speculated that testosterone released by males may play an important role in these phenomena. 3) Although the different sex ratios had no significant effect on the growth of females, the speed of ovarian development significantly increased when the female: male ratio was 1:2.
This thermal case pronounced the stability framework for stagnation point flow of magnetized alumina and copper nanoparticles with due exponentially shrinking permeable surface. The thermal stability and enhancement of water base liquid had been taken into account with uniform impulsion of hybrid nanomaterials. The induced flow results via exponentially shrinking permeable surface. The similarity transformation simplifies the mathematical model where governing formulated system for hybrid nanofluid is altered into the nondimensional form. A numerical solver called bvp4c is employed in MATLAB software to aid in the problem-solving process, and dual branches have been found. The significance of pertaining parameters associated to the flow model is inspected in view of thermal properties. The findings show that there are two branches for suction strength [Formula: see text] and magnetic strength [Formula: see text]. The bifurcation values [Formula: see text] and [Formula: see text] reduce for the occurrence of dual branches as the solid volume percentages of copper increase. Furthermore, for the upper branch solutions, the skin friction and heat transfer rate rise as [Formula: see text] increases. The temporal stability analysis determines the stability of the dual branches, and it is discovered that only one of them is stable and physically applicable. The presence of suction parameter effectively controls the thermal transportation phenomenon.
In this study, a novel nanocomposite of magnesium oxide doped graphene oxide (MgO@GO) visible-light driven photocatalyst was successfully synthesized for model Rhodamine 6G (Rh6G) degradation. This photocatalyst was comprehensively investigated to justify the morphology, structure, functional groups and chemical composition by Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and SEM-Energy-Dispersive X-ray Spectroscopy (SEM-EDS mapping). Four different methods were initially studied i.e. sun light, tungsten light (50 W), stirring and aeration separately for degradation of Rh6G (30 mL of 1 ppm) and obtained results as 33%, 61%, 25% and 7% within 6 h respectively. The new method was developed for combination of different techniques to achieve high efficiency of photocatalyst. The combination of three methods i.e. tungsten light (50 W), stirring (450 rpm) and aeration (4 L/min) delivered 98% degradation of Rh6G (30 mL of 1 ppm) within 15 min without any aid of scavenger. This is due to excellent enhancement of favorable photo-generated holes, hydroxyl radicals and higher photocurrent response intensity of MgO@GO compared to MgO and GO. It also reflects the synergistic effect of GO to enhance the charge separation efficiency. Additionally, a comparative evaluation of the photodegradation performance of MgO@GO, MgO and GO nanomaterials was also carried out. This work reveals that, a rational combination of GO and MgO can lead the efficient photocatalytic degradation of recalcitrant organic pollutants such as Rh6G.
The biosynthesis of the iron oxide nanoparticles was done using Ixoro coccinea leaf extract, followed by the fabrication of iron oxide nanobiocomposites (I-Fe3O4-NBC) using chitosan biopolymer. Furthermore, the synthesized I-Fe3O4-NPs and I-Fe3O4-NBC were characterized, and I-Fe3O4-NBC was applied to remove toxic metals (TMs: Cd, Ni, and Pb) from water. The characterization study confirmed that the nanostructure, porous, rough, crystalline structure, and different functional groups of chitosan and I-Fe3O4-NPs in I-Fe3O4-NBCs showed their feasibility for the application as excellent adsorbents for quantitative removal of TMs. The batch mode strategy as feasibility testing was done to optimize different adsorption parameters (pH, concentrations of TMs, dose of I-Fe3O4-NBC, contact time, and temperature) for maximum removal of TMs from water by Fe3O4-NBC. The maximum adsorption capacities using nanocomposites for Cd, Ni, and Pb were 66.0, 60.0, and 66.4 mg g−1, respectively. The adsorption process follows the Freundlich isotherm model by I-Fe3O4-NBC to remove Cd and Ni, while the Pb may be adsorption followed by multilayer surface coverage. The proposed adsorption process was best fitted to follow pseudo-second-order kinetics and showed an exothermic, favorable, and spontaneous nature. In addition, the I-Fe3O4-NBC was applied to adsorption TMs from surface water (%recovery > 95%). Thus, it can be concluded that the proposed nanocomposite is most efficient in removing TMs from drinking water up to recommended permissible limit.
Present study aimed to explore alterations of serum metal contents in patients of chronic kidney disease before and after haemodialysis (HD) compared to controls. For the levels of heavy metals in serum samples of kidney patients before and after HD belonging to different areas of Hyderabad and adjoining areas admitted at different hospitals of Hyderabad. In this study, the level of copper (Cu), zinc (Zn), chromium (Cr), iron (Fe) and manganese (Mn) in serum sample of kidney patients and controls have been investigated using Atomic Absorption Spectrophotometer (AAS). An increase in serum urea and serum creatinine levels in patients with chronic kidney disease (CKD) when compared to controls was observed and it was due to the decreased glomerular filtration in patients with CKD. The average of serum Cu and Cr were significantly high in pre-HD patients as compared to controls, reverse was found just in case of Mn and Fe. Serum Cu and Mn were significantly increased in post-HD patients when put next to the controls, whereas, serum Cr concentration was significantly decreased after HD in comparison to the controls. Concentration of serum Cu, Fe and Mn were significantly increased in post-HD patients as compared to the pre-HD patients. In conclusion, hemodialysis alters the serum metal contents in CKD patients. After the study, it is suggested that, serum metal contents before the dialysis session must be investigated more extensively to elucidate the alterations throughout the dialysis session and may be medicated accordingly.
Environmental contamination has been a major source of concern for the world in recent decades. Pollutants in the environment are harmful entities that can cause severe diseases and pose a serious threat to the ecosystem. As a result, it becomes compulsion for modern researchers to develop such remarkable sensors that are capable of detecting contaminants in aqueous environment. In order to develop a sensitive and selective sensor for the targeted determination of Bisphenol-A (BPA), an endocrine-disrupting compound, a very efficient Cd/rGO composite was synthesized through a green microwave-assisted route. The prepared Cd/rGO composite was characterized by different analytical tools, e.g. XRD, EDX, FTIR and SEM, to study phase structure, elemental composition, functionalities, and sheets morphology, respectively. To evaluate the sensing properties of fabricated sensing material glassy carbon electrode was modified and resulting Cd/rGO/GCE was initially electrochemically characterized using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (ESI). At optimized conditions such as scan rate of 70 mV/s, PBS electrolyte of pH 7, potential window in the range of 0.0–0.9 V vs Ag/AgCl; the fabricated Cd/rGO/GCE-based sensor showed the outstanding response for BPA. Under the linear concentration range from 5 to 110 µM, the LOD and LOQ were calculated as 0.041 and 0.13 µM, respectively. Moreover, the analytical applicability of the proposed sensor was tested in different water samples, which revealed acceptable recovery values from 91.1 to 101.1%. The comprehensive experimental studies witness the reliability of the proposed method and confirm that it could be a promising electrochemical sensor to be used at the commercial level. Graphical abstract
In the low voltage applications, the high gain multilevel inverters has seen more visibility due to the improved harmonic profile with multilevel voltage as well as boosting feature. A boost active neutral point clamped (ANPC) multilevel inverter (MLI) configuration with reduced resource count has been proposed in this paper. The proposed MLI produces 11 levels (11L) voltage with the help of 12 switches of blocking voltage ratings lesser than the peak value of output voltages. For attaining the boosting of 2.5 in output voltage, 4 capacitors are used in the proposed MLI which are inherently self-balanced. The capacitors charging as well as discharging are done by implementing the simple logic of parallel/series connection with the active power DC source. The proposed MLI is implemented and tested in the laboratory at various operating conditions, and the corresponding results and discussion are presented.
The quality and thermo-oxidative stability of soybean oil (SO), palm olein oil (POO), canola oil (CO) and their blends were evaluated. The binary blends of SO:POO and CO:POO were formulated in a ratio of (75:25) and ternary blend were prepared by blending CO:POO:SO in a ratio of (35:30:35). To monitor the thermal stability of pure oils and their blends, they were subjected to temperature (180°C) at different time intervals. The results revealed that at elevated temperature the quality of pure and blended oils deteriorate significantly. Heating process led to a substantial increase in free fatty acid (FFA), peroxide value (PV), p-anisidine value (p-AV), and saponification value (SV), while iodine value (IV) and oxidative stability index (OSI) decreased. However, blends comparatively showed better nutritional status and stability than the pure ones. The Principal component analysis (PCA) of all parameters was also performed. The data provide three significant principal components (PCs with eigenvalue ˃1), which collectively report 98.8% of the total variance. PC1 contributed mainly with total (50.1%) followed by PC2 (36.2%) and PC3 (12.5%) in the data. This work suggests that blending POO with other oils that contain more unsaturatation could be an effective and eco-friendly procedure which enhances the chemical sustainability and nutritional content of the oil.
Present study reports the hydrothermal synthesis procedure to prepare the facile and sustainable orthorhombic Molybdenum trioxide (α-MoO3) nanoparticles (NPs) for the degradation of thymol blue dye. Synthesized α-MoO3NPs was characterized by FTIR, XRD, Zeta-potential, SEM, and TEM to investigate the functionalities, texture, size, and morphology of α-MoO3 NPs. The average size was calculated up to 68 ± 5 nm. The α-MoO3NPs was successfully applied to degrade toxic organic dye (thymol blue) in aqueous media. To achieve maximum percentage degredation of dye different parameters were optimized, including a catalyst dose, reaction time, effect of microwave irradiation at low power, reproducibility of catalyst. At optimum conditions, the fabricated α-MoO3NPs-based heterogeneous nano-catalyst was highly efficient for degrading thymol blue dye in aqueous media; the percentage degradation was obtained up to 99% within 60 s just using 120 µg of α-MoO3NPs was used under the microwave radiations. The heterogeneous nano-catalyst shows excellent performance and is highly efficient as compared to previously reported work. Graphical Abstract The schematic diagram for the degradation of thymol blue dye using prepared MoO3 nano-catalyst
The new objective of sustainable analytical chemistry is to develop validated robust, swift, simple and highly sensitive analytical methods that are based on cost effective sensing technology. Therefore, in this study the electro-chemical detection of coenzyme Q10 (CoQ10) was achieved using a fluorene intercalated graphene oxide based CoQ10 imprinted polymer composite modified glassy carbon electrode (CoQ10-IGOPC/GCE). The synthesized sensing material was characterized using SEM, XRD and FT-IR to determine the morphology and functional properties. The CoQ10-IGOPC/GCE was characterized by EIS for its electrochemical properties. CoQ10 was detected selectively using Differential Pulse Voltammetry (DPV). Under ideal circumstances, a linear calibration curve with a correlation coefficient (R 2) of 0.991 was produced in the concentration range of 0.0967 to 28.7 μM. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.029 and 0.0967 μM, respectively. Furthermore, the proposed electrochemical sensor was extremely selective, accurate and thoroughly validated with RSD values less than 5%. The developed CoQ10-IGOPC/GCE based electrochemical sensor was successfully used for the detection of CoQ10 in samples of fruits, vegetables, nuts, human blood serum and pharmaceuticals. The CoQ10-IGOPC/GCE based electrochemical method showed good percent recoveries ranging from 94 to 103 percent.
In the present study, carboxymethyl cellulose (CMC) is dispersed in polystyrene block polyisoprene block polystyrene polymer (PSIS) to make a composite film (CMC-PSIS) through a simple casting technique followed by adsorption of Cu and Ni ions from their respective salt solution. After that, it was converted to their respective Cu⁰ and Ni⁰ nanoparticles (NPs) in aqueous medium in the presence of NaBH4 on the surface of CMC-PSIS and was named as CMC-PSIS/Cu and CMC-PSIS/Ni respectively. The prepared catalysts were extensively characterized through different techniques. The morphology of catalysts was studied using FESEM while the EDS and XPS techniques were used for determining the elemental composition and binding energy of both the catalyst. Similarly, FTIR and XRD were used for functional groups and crystalline nature determination of the catalysts. Both catalysts were applied as dip-catalyst in the presence of NaBH4 as reducing agent against the reduction/degradation of four model pollutants such as 4-nitrophenol, methylene blue, rhodamine B (RB), and methyl orange dyes (MO). The highest rate constant value (3.75 ×\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\times$$\end{document} 10–1 min⁻¹) was observed for the MO degradation using CMC-PSIS/Cu. Similarly, the shortest reaction time i.e., (3 min) was observed for MO degradation by using Cu NPs. The RB degraded up to maximum extent (97.7%) among all dyes by using CMC-PSIS/Ni. The experimental data was well-fitted in the zeroth order of kinetics.
A multifaceted, holistic approach to identifying potential predictors is needed to eradicate workplace bullying. The current study investigated the impact of an unfavourable organisational climate that plays a role in breeding workplace bullying (social stressors). The present study also postulated that individual personality differences (Type A and Type B personality) mediate between a caring climate and workplace bullying. Similarly, the interaction between workplace bullying and personality impacts PTSD. We also checked the role of workplace bullying as a mediator between a caring climate and PTSD. This research tested all the proposed hypotheses ( N = 298), and the study was conducted in Pakistan. The data is analysed using the two-step partial least square structural equation modelling (PLS-SEM) procedure. The first part assesses the measurement model, while in the second step, the structural model is evaluated. The results supported all the proposed hypotheses of this study. Type A behaviour moderated the caring climate—person-related bullying relationship, whereas it did not moderate the caring climate—work-related bullying in the suggested direction. Type A behaviour is moderated for both types of bullying and PTSD. Results also show significant indirect effects of a caring climate on PTSD through workplace bullying. This study will contribute theoretically to filling the literature gap on studies of climate-bullying and bullying-stress using contingency factors.
Despite massive research in deep learning, the human activity recognition (HAR) domain still suffers from key challenges in terms of accurate classification and detection. The core idea behind recognizing activities accurately is to assist Internet-of-things (IoT) enabled smart surveillance systems. Thereby, this work is based on the joint use of discrete wavelet transform (DWT) and recurrent neural network (RNN) to classify and detect human activities accurately. Recent approaches on HAR exploit the three-dimensional (3-D) convolutional neural networks (CNNs) to extract spatial information, which adds a computational burden. In our case, features are extracted using 3D-DWT instead of 3-D CNNs, performed in three steps of 1D-DWT to reflect the spatio-temporal features of human action. Given the features, the RNN produces an output label for each video clip taking care of the long-term temporal consistency among close predictions in the output sequence. It is noticed that feature extraction through 3D-DWT essentially recovers the multiple angles of an activity. Many HAR techniques distinguish an activity based on the posture of an image frame rather than learning the transitional relationship between postures in the temporal sequence, resulting in degraded accuracy. To address this problem, in this article, we designed a novel rank-based fuzzy approach that segregates activities precisely by ranking the probabilities of activities based on confidence scores. FuzzyAct achieved an average mean average precision (mAP) of 0.8012 mAP on the ActivityNet dataset, and outperformed the baseline counterparts and other state-of-the-art approaches on benchmark datasets. Finally, we present a mechanism to compress the proposed RNN for edge-enabled IoT applications.
Quetta Valley is part of the Pishin Sub-basin is in the northern section of the Kirthar Belt and has Lower Jurassic to Holocene strata. It is an arid mountainous region with low mean annual precipitation of 150-200 mm between 1999 and 2019. The population of Quetta City has increased from 0.26 million in 1975 to 3.0 million in 2016, causing an increased burden on groundwater now it is depleting at an alarming rate of 1.5-5.0 m/year in certain parts of the city. The Quetta Valley comprises of two types of aquifers: the alluvial aquifer and the limestone aquifer. The issue of unmanaged groundwater depletion is present in many areas of Quetta City. The alluvial and limestone aquifers in the Quetta Valley were depleted after two decades of heavy use from hundreds of illegal tube wells and agricultural wells. With the increasing population and low precipitation of the Quetta Valley, this review paper examines many variables that contribute groundwater depletion. According to earlier research, uncontrolled pumping of groundwater resources has deteriorated water quality and reduced its quantity in the Quetta Valley. The current study predicted an overall reduction in the static water table in the limestone aquifer between 1.0 to 2.5 m/year over the water years 1987 to 2020. In contrast, it was estimated to be 1.5 to 5.0 m/year in the alluvial aquifer.
In current the study, simple, rapid, sensitive and selective alkanol-based supramolecular solvent-assisted dispersive liquid-liquid microextraction (SSA-DLLME) method was first time developed for the extraction and determination of acrylamide (AA) in coffee, chocolate, roasted nuts, French fries, cereals, biscuits, chips, bread and caramelized fruit using UV-visible spectrophotometer. Different study parameters were investigated and optimized to know their effects on the extraction of AA. Studies have shown that effective extraction of AA was achieved at short vortex time (2 min) and acidic pHs. Extraction of AA was inversely proportional to sample volume. The linear range (LR) of the SSA-DLLME method was 0.6-350 ng mL⁻¹. The limit of detection (LOD), and limit of quantification (LOQ) were found to be 0.2 ng mL⁻¹ and 0.6 ng mL⁻¹, respectively. In addition, enhancement factor and preconcentration factor was 114 and 200, respectively. Factorial design was utilized to better understand dual effluents of factors on extraction recovery of the AA. Optimized SSA-DLLME method was successfully applied to processed food samples for the determination of AA.
Twenty-six groundwater samples from the dug well aquifer were collected during April 2021 from the Chachro sub-district, Sindh, Pakistan to know the hydrogeochemical characteristics and groundwater quality for domestic and agricultural purpose. Multivariate statistical, Chloro alkaline indices result and scatter plots confirm the ion-exchange process in the study region. The Gibbs diagram indicated that rock weathering and evaporation were significant processes that control groundwater chemistry. Piper and Chada's diagram suggested that groundwater was Na⁺, K⁺, Cl⁻, SO4⁻² type and suggested that alkali exceeds alkaline earth metals and strong acidic exceeds weak acidic anions. PCA and correlation coefficient reveal that TDS, EC, Mg⁺², Na⁺, Cl⁻, SO4⁻² were positively correlated and similar is confirmed through HCA. The statistical results reveal the dominant decreasing order amongst the cations Na⁺>Ca⁺²>Mg⁺²>K⁺ and in anions, Cl− > HCO3>SO4. Based on the DWQI, 50% were unsuitable for drinking. Wilcox and USSLH diagram reveal that most samples clustered in very high salinity and very high sodium water type were not suitable for agriculture use. Sodium absorption ratio (SAR), Kelly's ratio (KR) and Sodium percentage Na% reveal that most groundwater samples were unfit for agriculture use. However, Residual sodium carbonate (RSC) and Results of permeability index (PI) were suitable for irrigation purposes.
Rice (Oryza sativa L.) is a major cereal and staple food crop worldwide, and its growth and production are affected by several fungal and bacterial phytopathogens. Bacterial blight (BB) is one of the world’s most devastating rice diseases, caused by Xanthomonas oryzae pv. oryzae (Xoo). In the current study, Bacillus atrophaeus FA12 and B. cabrialesii FA26 were isolated from the rice rhizosphere and characterized as having broad-range antifungal and antibacterial activities against various phytopathogens, including Xoo. In addition, the selected strains were further evaluated for their potent rice growth promotion and suppression efficacy against BB under greenhouse conditions. The result shows that FA12 and FA26, applied as seed inoculants, significantly enhanced the vigor index of rice seedlings by 78.89% and 108.70%, respectively. Suppression efficacy against BB disease by FA12 and FA26 reached up to 59.74% and 54.70%, respectively, in pot experiments. Furthermore, MALDI-TOF MS analysis of selected strains revealed the masses ranged from m/z 1040 to 1540, representing that iturins and fengycin are the major antimicrobial compounds in the crude extracts, which might have beneficial roles in rice defence responses against BB. In conclusion, FA12 and FA26 possess broad-range antagonistic activity and have the capability to promote plant growth traits. More importantly, applying these strains has a high potential for implementing eco-friendly, cost-effective, and sustainable management practices for BB disease.
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1,193 members
Aamna Balouch
  • National Centre of Excellence in Analytical Chemistry
Muhammad Aqeel Bhutto
  • Institute of Biotechnology and Genetic Engineering
Naseem Aslam Channa
  • Institute of Biochemistry
Jameel Ahmed Baig
  • National Centre of Excellence in Analytical Chemistry
Muhammed Umar Dahot
  • Institute of Biotechnology and Genetic Engineering
Information
Address
76080, Jamshoro, Sindh, Pakistan
Website
www.usindh.edu.pk
Phone
+92-22-9213-181-90