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Abstract This study empirically investigates the linkage between boardroom independence and the financial performance of non-financial firms in an emerging market featured by family-controlled businesses and concentrated ownership. The relationship is tested in a sample of 152 non-financial firms listed on the Pakistan Stock Exchange over a period from 2003 to 2018. Firms’ financial performance is measured through return on assets (ROA), return on equity (ROE), market-to-book ratio (MBR), and Tobin’s Q (TQ), while boardroom independence is measured through the proportion of non-executive directors on the corporate board. Using the dynamic GMM approach to address the possibility of endogeneity, it was found that boardroom independence is significantly negatively related to the financial performance of the sample firms. This negative impact is due to the reason of close ties of outside independent directors (non-executive directors) with dominant shareholders and management in personal, financial, and social terms. A significant negative influence of the board size and CEO duality on firms’ financial performance was also observed. The present study will add to the existing literature on corporate governance and firm financial performance using firm-level manually collected data. Further, our findings will also help the policymakers by providing empirical insights for strengthening corporate governance mechanisms in emerging market economies, specifically in the context of Pakistan.

Long-term live cell imaging requires sophisticated and fully automated commercial-stage incubators equipped with specified inverted microscopes to regulate temperature, CO2 content, and humidity. In this study, we present a CO2-free on-stage incubator specifically designed for use across various cell culture platforms, enabling live cell imaging applications. A simple and transparent incubator was fabricated from acrylic sheets to be easily placed on the stages of most inverted microscopes. We successfully performed live-cell imaging of cholangiocarcinoma (CCA) cells and HeLa cell dynamics in both 2D and 3D microenvironments over three days. We also analyzed directed cell migration under high serum induction within a microfluidic device. Interesting phenomena such as “whole-colony migration”, “novel type of collective cell migration” and “colony formation during cell and colony migration” are reported here for the first time, to the best of our knowledge. These phenomena may improve our understanding of the nature of cell migration and cancer metastasis.

This study aims to formulate experimental vinylpolysiloxane (VPS) impression materials and compare their elastic recovery and strain-in-compressions with three commercial VPS materials (Aquasil, Elite, and Extrude). Five experimental materials (Exp), two hydrophobic (Exp-I and II) and three hydrophilic (Exp-III, IV and V) were developed. Exp 1 contained vinyl-terminated poly-dimethyl siloxane and a conventional cross-linking agent (poly methylhydrosiloxane), while Exp- II contained a novel cross-linking agent that is tetra-functional dimethyl-silyl-ortho-silicate (TFDMSOS). Exp III–V (hydrophilic materials) were formulated by incorporating different concentrations of non-ionic surfactant (Rhodasurf CET-2) into Exp II formulation. Measurement of elastic recovery and strain-in-compression for commercial and experimental materials were performed according to ISO4823 standard using the calibrated mechanical testing machine (Tinius Olsen). One-way analysis of variance (one-way ANOVA) and Tukey’s post-hoc (HSD) test were used for statistical analysis and a p-value of ≤ 0.05 was considered significant. Exp-I has statistically similar values to commercial VPS. The Exp-II showed the highest elastic recovery, while % elastic recovery was reduced with the addition of the non-ionic surfactant (Rhodasurf CET-2). The % reduction was directly related to the concentration of Rhodasurf CET-2. In addition, Exp II had significantly higher strain-in-compression values compared to Exp-I and commercial materials. These values were further increased with the addition of a non-ionic surfactant (Rhodasurf CET-2) was added (Exp-III, IV and V).

This is a case report of a previously healthy female patient with complement-mediated thrombotic microangiopathy (TMA) caused by a systemic cytomegalovirus infection that was successfully treated with plasmapheresis, steroids, and parenteral valganciclovir. Complement-mediated TMA is the result of various genetic mutations leading to complement abnormalities with overactivation of alternate complement pathway in response to a triggering infection. She also had splenic rupture without splenomegaly and was managed successfully without splenectomy.

Abstract The invasion of drilling fluids during well drilling through gas hydrate‐bearing sediments may seriously damage gas hydrate stability and distort well‐logging identification and evaluation in exploration and production of gas hydrate reservoirs. Adding nanoparticles into drilling fluids can be an efficient method to reduce fluid invasion. However, nanoparticles may induce hydrate formation in wells, which will block annulus and lead to safety accidents. Therefore, suitable nanoparticles used for hydrate drilling should be clarified first. This study addressed this issue by experimentally investigating the influence of hydrophilic and hydrophobic nano‐CaCO3 on CH4 hydrate formation in a dynamic system. We performed a series of experiments by using nano‐CaCO3 (1.0–6.0 wt%) with different particle sizes (20, 70, and 700 nm) at 3.0 °C and 6.0 MPa. The macroscopic kinetic parameters of hydrate formation were obtained. The results show that hydrophobic nano‐CaCO3 particles promote hydrate formation, while hydrophilic ones can inhibit hydrate formation at certain particle sizes and concentrations. This is mainly due to the different surface wettability, resulting in the different distribution of water and gas molecules in fluids. The hydrophilic nano‐CaCO3 with the particle size of 20 nm and addition of 3.0 wt% has the strongest inhibition effect under the given experimental conditions. In comparison with ultrapure water, the induction time is increased by about 38%, while the formation amount and rate are decreased by about 13% and 18%, respectively. This work will provide valuable ideas and references for the design of deepwater drilling fluid using nanoparticles, and also provide insight into revealing the formation and evolution mechanism of hydrate deposits at the micropore or even nanopore scale.

With growing urbanization and increasing world population, energy demand also increases. A significant portion of the world’s energy comes from fossil fuels, and these sources of energy are declining rapidly at the current consumption rate. There are also growing environmental concerns on the use of fossil fuels increasing greenhouse gas emissions. In this regard, renewable energy (RE) shows promising solutions which are both sustainable and environmentally friendly. Developed countries and leading organizations are investing heavily in the RE sector. However, the developing world has anxieties over social acceptability and people’s willingness to pay for renewable energy. This study is conducted in Pakistan to understand the public perception and willingness to pay. The Theory of Planned Behavior (TPB) was utilized with background factors such as awareness, perceived advantages, perceived challenges, and moral obligations to examine its influence on people’s willingness to pay. In addition to this, the study also assessed the indirect effects of background factors (awareness, perceived advantages, and perceived challenges) on willingness to pay through public attitude. Furthermore, the indirect relationship between background factors (awareness and moral obligation) and willingness to pay through subjective norms was also examined. A total of 512 samples were gathered from participants and were analyzed through partial least square–structural equation modeling (PLS-SEM) and SPSS. The study findings are very interesting and back up our hypotheses that the background factors (awareness, perceived advantages, and perceived challenges) are positively associated with public attitude and have an indirect effect on willingness to pay through public attitude. Similarly, variables such as awareness and moral obligation are negatively and positively associated with subjective norms, respectively. However, the variables, awareness and moral obligation, have no indirect relationship with willingness to pay through subjective norms. Additionally, the study reveals that the components (attitude and perceived behavior control) of TPB have a significantly positive effect on willingness to pay. The study also concludes that the participants having formal education and knowledge about climate change and renewable energy are inclined toward green energy and are willing to pay, and they are hardly influenced by others' opinions. Furthermore, the study also provides insights for policymakers, suggestions, and recommendations for the future.

The ready-mixed concrete delivery (RMC) problem is a scheduling problem, where multiple trucks deliver concrete to order sites abiding by hard constraints in a dynamic environment. It is an NP-hard problem, impractical to solve using exhaustive methods. Thus, it requires heuristic-based approaches for generating sub-optimal schedules. Due to its distributed nature, we address this problem using a decentralised, scalable, cooperative MAS (multiagent system) that dynamically generates schedules. We explore the impact of teamwork by trucks on schedule optimisation. This work illustrates two novel approaches that address the dynamic RMC problem; a Delegate MAS approach and a team-extended approach. We present an empirical study, comparing our novel approaches with existing ones. The evaluation is performed by classifying the RMC case study scenarios into unique stress, scale, and dynamism characteristics. With 40% to 70% improvement over different metrics, the results show that both approaches generate better schedules, and using agent teams augments the performance. Thus, such decentralized MAS with the appropriate coordination approach and teamwork can be used for solving constrained dynamic scheduling problems.

Coronavirus disease 2019 (COVID-19) has infected millions of people worldwide. Vaccines are urgently needed to mitigate COVID-19 pandemic and return to the pre-pandemic era. The aims of the current literature review were to discuss the administered vaccines and\or those under trials, and to summarize the effectiveness of the available COVID-19 vaccines. Scientists worldwide have made extensive efforts for vaccine development in record time. Several vaccine candidates have been developed; where many of them have passed stage III clinical trials and have recorded positive results. Scientists throughout the world are exerting enormous efforts for the development of COVID-19 vaccine. About 18 vaccines candidates are currently in phase III clinical trial. Almost all the developing vaccine candidates have T cell response and detectable numbers of neutralizing antibodies. The most common vaccine side effects include; fever, chills, fatigue, headache, muscle and joint pains. The post stage III successful vaccines have been administered to individuals worldwide.

Nanoparticles (NPs) are commonly used in healthcare and nanotherapy, but their toxicity at high concentrations is well-known. Recent research has shown that NPs can also cause toxicity at low concentrations, disrupting various cellular functions and leading to altered mechanobiological behavior. While researchers have used different methods to investigate the effects of NPs on cells, including gene expression and cell adhesion assays, the use of mechanobiological tools in this context has been underutilized. This review emphasizes the importance of further exploring the mechanobiological effects of NPs, which could reveal valuable insights into the mechanisms behind NP toxicity. To investigate these effects, different methods, including the use of polydimethylsiloxane (PDMS) pillars to study cell motility, traction force production, and rigidity sensing contractions, have been employed. Understanding how NPs affect cell cytoskeletal functions through mechanobiology could have significant implications, such as developing innovative drug delivery systems and tissue engineering techniques, and could improve the safety of NPs for biomedical applications. In summary, this review highlights the significance of incorporating mechanobiology into the study of NP toxicity and demonstrates the potential of this interdisciplinary field to advance our knowledge and practical use of NPs.

Objectives This study aims to describe the perception of dental professionals in Pakistan and Saudi Arabia (SA) towards the practice of teledentistry, its usefulness and challenges. Methods A cross-sectional study was carried out among 190 dentists from January 2021 to April 2021. The participants were included in the study using snowball sampling method. A 26-item adopted questionnaire was distributed using different social media channels. Chi-square test was used for analysis. Results Out of 190 participants, 46.3% were from Pakistan and 53.7% were from SA. The majority of participants in both countries agreed that teledentistry would enhance guidelines and advice (74.2%), improve peer-to-peer interaction (79.5%) and make patient's referrals more efficient (75.8%). For the usefulness, most participants agree that it is economical for the patients (61.1%), improves communication (74.7%), helps in educating the patients (86.3%), avoid unnecessary travel (76.8%), helps monitoring (71.6%), and benefits patients in remote areas (74.7%); however, more Pakistani participants perceived that time spent with the patient would increase compared to SA participants ( p

Background Dental impressions are used to record anatomy of teeth and surrounding oral structures. Impression materials become contaminated with saliva and blood requiring disinfection, which may have negative impact on dimensional stability of materials. Objective Comparatively evaluate linear dimensional changes of synthesized Tetra-functional (dimethylsilyl) orthosilicate (TFDMOS) containing Polyvinylsiloxane (PVS) impressions following sodium hypochlorite disinfection. Methods Percentage dimensional changes of three commercial PVS (Elite HD Monophase, Extrude and Aquasil Ultra Monophase) and five experimental PVS impression materials were measured. Experimental material contained novel cross-linking agent (TFDMOS) and a non-ionic surfactant (Rhodasurf CET-2) that is Exp-A (without TFDMOS), Exp-B (with TFDMOS), Exp-C (TFDMOS+ 2% Rhodasurf CET-2), Exp-D (TFDMOS+ 2.5% Rhodasurf CET-2) Exp-E (TFDMOS+ 3% Rhodasurf CET-2). Samples were made using rectangular stainless-steel molds (40 × 10 × 3 mm3) and linear dimensional changes were measured using a calibrated travelling microscope at 10× magnification after immersion in distilled water (D.W) and 1% Sodium Hypochlorite solution at two different time intervals i.e., 30 min and 24 h. Results Samples immersed in 1% NaOCl showed significant (p < 0.05) dimensional changes after 30 min of immersion. Exp-E showed significantly greater dimensional changes than their control (Exp-A and Exp-B). In distilled water, there were no significant difference among the tested materials. Aquasil exhibited highest expansion (0.06%) in both solutions. At 24 h, among the commercial materials, Extrude had the greatest expansion followed by Aquasil and Elite in DW while Aquasil showed the greatest expansion followed by Extrude and Elite in NaOCl. Conclusion Experimental PVS had linear dimensional changes within the ISO 4823; 2015 recommended range. However, extended immersion can negatively affect the linear dimensions.

This paper evaluated the oil and gas potential of the Cretaceous Yageliemu clastic reservoir within the Yakela condensed gas field lying in the Kuqa Depression, Tarim Basin, China. The petrophysical properties of the interest zones in the Kuqa area were characterized using geophysical logs from five wells. The results reveal that the gas-bearing zones are characterized by high resistivity, good permeability (K) and effective porosity (Φeff), low water saturation (Sw), and low shale concentration (Vsh), reflecting clean sand. The shale distribution model showed that these shales have no major influence on porosity and fluid saturation. The average shale volume, average effective porosity, and hydrocarbon saturation indicate that the Cretaceous Yageliemu Formation in the studied area contains prospective reservoir properties. The spatial distribution of petrophysical parameters, reservoir rock typing (RRT), and lithofacies were analyzed using the cross plots of litho saturation (volumetric analysis), iso-parametric representations of the petrophysical characteristics, cluster analysis, and self-organizing feature maps, respectively. The southeastern and northeastern regions of the research area should be ignored because of their high water and shale concentrations. The sediments in the southwest and northwest include the most potential reservoir intervals that should be considered for the future exploration and development of oil and gas fields in the study area.

Artificial intelligence (AI)-based multispectral remote sensing has been the best supporting tool using limited resources to enhance the lithological mapping abilities with accuracy, supported by ground truthing through traditional mapping techniques. The availability of the dataset, choice of algorithm, cost, accuracy, computational time, data labeling, and terrain features are some crucial considerations that researchers continue to explore. In this research, support vector machine (SVM) and artificial neural network (ANN) were applied to the Sentinel-2 MSI dataset for classifying lithologies having subtle compositional differences in the Kohat Basin’s remote, inaccessible regions within Pakistan. First, we used principal component analysis (PCA), minimum noise fraction (MNF), and available maps for reliable data annotation for training SVM and (ANN) models for mapping ten classes (nine lithological units + water). The ANN and SVM results were compared with the previously conducted studies in the area and ground truth survey to evaluate their accuracy. SVM mapped ten classes with an overall accuracy (OA) of 95.78% and kappa coefficient of 0.95, compared to 95.73% and 0.95 by ANN classification. The SVM algorithm was more efficient concerning computational efficiency, accuracy, and ease due to available features within Google Earth Engine (GEE). Contrarily, ANN required time-consuming data transformation from GEE to Google Cloud before application in Google Colab.

This paper aims to investigate the phenomenon of online political participation in a cross cultural context by applying the concept of cognitive engagement theory. The relationship of access to political stuff on social media, political interest, and policy satisfaction with online political participation is studied in the context of Pakistan and Malaysia. The variable of political knowledge is used as a moderator in the study in order to reveal deeper insights. Data were collected from a sample of 504 students from COMSATS University Islamabad and University Utara Malaysia. In Pakistani context, political interest, policy satisfaction, and political knowledge show a positively significant result, whereas online incivility shows a negatively significant outcome. In the context of Malaysia, availability of political stuff online, political interest, policy satisfaction, and political knowledge shows a positively significant impact on online political participation. Political knowledge holds as a moderator in Malaysia but not in Pakistan. This paper has theoretical as well as the practical contribution in developing an understanding about political participation through social media in both Pakistan and Malaysia. Furthermore, cognitive engagement theory is also used on a rare basis, and hence, this paper adds to the generalization of the theory.

Background: This study aimed to develop an Urdu version of Child-Oral Impact on Daily Performance (C-OIDP) and assess its reliability and validity for children’s oral health-related quality of life (OHRQoL) assessment in Pakistan. Methods: A total of 200 school-going children aged 11–14 were recruited from two public schools. For the adaptation process, the original English version of C-OIDP was translated into Urdu, reviewed by an expert committee, back-translated into Urdu, and then reviewed again by the same expert committee and pilot tested on 10 children. A clinical examination was carried out to record dental and gingival status followed by a face-to-face interview to measure oral health-related quality of life in children using C-OIDP-U. Reliability, internal consistency, construct and discriminant validity were assessed. Results: The Cronbach’s alpha for C-OIDP-U was 0.69, the mean C-OIDP-U score was 10.2 ± 8.1 and 77.3% of the children reported at least one oral impact. Eating (40.3%) and difficulty in cleaning mouth (38.7%) were the two most impacted daily performances. For construct validity, the associations were significant between the C-OIDP-U score and all subjective oral health measures (p < 0.001). For discriminant validity, a significant association was observed between the C-OIDP-U score and clinical oral variables, children with DMFT + dmft ≥ 1, Gingival index > 1 and having malocclusion reported a higher C-OIDP-U score when compared to their counterparts. Conclusion: This study showed that C-OIDP is a valid, reliable and efficient instrument of OHRQoL for use in Pakistani children.

Despite low spatial resolutions, thermal infrared bands (TIRs) are generally more suitable for mineral mapping due to fundamental tones and high penetration in vegetated areas compared to shortwave infrared (SWIR) bands. However, the weak overtone combinations of SWIR bands for minerals can be compensated by fusing SWIR-bearing data (Sentinel-2 and Landsat-8) with other multispectral data containing fundamental tones from TIR bands. In this paper, marble in a granitic complex in Mardan District (Khyber Pakhtunkhwa) in Pakistan is discriminated by fusing feature-oriented principal component selection (FPCS) obtained from the ASTER, Landsat-8 Operational Land Imager (OLI), Thermal Infrared Sensor (TIRS) and Sentinel-2 MSI data. Cloud computing from Google Earth Engine (GEE) was used to apply FPCS before and after the decorrelation stretching of Landsat-8, ASTER, and Sentinel-2 MSI data containing five (5) bands in the Landsat-8 OLI and TIRS and six (6) bands each in the ASTER and Sentinel-2 MSI datasets, resulting in 34 components (i.e., 2 × 17 components). A weighted linear combination of selected three components was used to map granite and marble. The samples collected during field visits and petrographic analysis confirmed the remote sensing results by revealing the region’s precise contact and extent of marble and granite rock types. The experimental results reflected the theoretical advantages of the proposed approach compared with the conventional stacking of band data for PCA-based fusion. The proposed methodology was also applied to delineate granite deposits in Karoonjhar Mountains, Nagarparker (Sindh province) and the Kotah Dome, Malakand (Khyber Pakhtunkhwa Province) in Pakistan. The paper presents a cost-effective methodology by the fusion of FPCS components for granite/marble mapping during mineral resource estimation. The importance of SWIR-bearing components in fusion represents minor minerals present in granite that could be used to model the engineering properties of the rock mass.

Low-resolution Geological Survey of Pakistan (GSP) maps surrounding the region of interest show oolitic and fossiliferous limestone occurrences correspondingly in Samanasuk, Lockhart, and Margalla hill formations in the Hazara division, Pakistan. Machine-learning algorithms (MLAs) have been rarely applied to multispectral remote sensing data for differentiating between limestone formations formed due to different depositional environments, such as oolitic or fossiliferous. Unlike the previous studies that mostly report lithological classification of rock types having different chemical compositions by the MLAs, this paper aimed to investigate MLAs’ potential for mapping subclasses within the same lithology, i.e., limestone. Additionally, selecting appropriate data labels, training algorithms, hyperparameters, and remote sensing data sources were also investigated while applying these MLAs. In this paper, first, oolitic (Samanasuk), fossiliferous (Lockhart and Margalla) limestone-bearing formations along with the adjoining Hazara formation were mapped using random forest (RF), support vector machine (SVM), classification and regression tree (CART), and naïve Bayes (NB) MLAs. The RF algorithm reported the best accuracy of 83.28% and a Kappa coefficient of 0.78. To further improve the targeted allochemical limestone formation map, annotation labels were generated by the fusion of maps obtained from principal component analysis (PCA), decorrelation stretching (DS), X-means clustering applied to ASTER-L1T, Landsat-8, and Sentinel-2 datasets. These labels were used to train and validate SVM, CART, NB, and RF MLAs to obtain a binary classification map of limestone occurrences in the Hazara division, Pakistan using the Google Earth Engine (GEE) platform. The classification of Landsat-8 data by CART reported 99.63% accuracy, with a Kappa coefficient of 0.99, and was in good agreement with the field validation. This binary limestone map was further classified into oolitic (Samanasuk) and fossiliferous (Lockhart and Margalla) formations by all the four MLAs; in this case, RF surpassed all the other algorithms with an improved accuracy of 96.36%. This improvement can be attributed to better annotation, resulting in a binary limestone classification map, which formed a mask for improved classification of oolitic and fossiliferous limestone in the area.

Lower respiratory tract infections are a common problem in our society. In recurrent lower respiratory tract infections the cause may be either general impairment of immune mechanism, abnormalities of mucus or abnormalities of cilia. We report a case where the patient was having recurrent lower and upper respiratory tract infections and had situs inversus totalis. The present case i.e. Kartagener’s syndrome is an inherited disorder transmitted in autosomal recessive manner with variable penetrance. Although there is no specific treatment for this condition, failure to recognize the condition may subject the patient to unnecessary repeated admissions and investigations and inappropriate treatment.

Laboratory and field performances (WHO Prequalified Vector Control products) of temephos 1 G, temephos 50 EC as larvicide, Alphacypermethrin 10 SC and Lambdacyhalothrin 2.5% EC as adulticides were evaluated on different life stages of Aedes aegypti. Percent mortalities at different time intervals on recommended doses have revealed marked differences under laboratory and field conditions after the 5th day of application. In laboratory conditions maximum mortality percentage started from 98.29% after 48 hours of application, showed a dip on 4th and 8th day while for rest of the period till the 10th day fluctuated between 87.72 to 95%. The field mortality together with residual life was relatively lower as compared to laboratory test results. Under field conditions, maximum mortality started from 96.67% on day one and thereafter declined continuously to 38.33% in Lahore. A similar trend of decline was reported in Rawalpindi and Faisalabad i.e., 98.33 to 38.33% and 96.67 to 18.33% (P<0.001) respectively. Similarly, Temephos 50 EC gave field mortality between 100-83.33 till 5th day in three districts while in laboratory experiments it gave 100 to 98.33% mortality up to 10th day with few dips on 5th to 6th day of application. The field mortality rate declined rapidly from 10th day to 22nd days of application under field conditions. IRS with Alphacypermethrin 10 SC water based painted walls showed maximum mortality between 33.33-53.33% while on cemented walls the mortality remained very low i.e., 20-26.67% after 45 minutes of exposure. Lambdacyhalothrin 2.5% EC yielded maximum mortality of 90 % after 1hour of fogging in trials in places with high Aedes mosquito adults. We also checked the effect of distance of fogging on caged population and found that Aedes aegypti population fogged at 6 feet distance gave 88.75% mortality. We have concluded that according to WHO prescribed criteria on residual efficacy, insecticides, doses have different residual effect under laboratory and field conditions. The study therefore provides a strong basis for testing these chemicals against Aedes aegypti mosquitoes and redefining the application schedule for reducing the vector population. [ABSTRACT FROM AUTHOR]