Stability and bifurcation analysis of a discrete predator-prey system of Ricker type with refuge effect.

The refuge effect is critical in ecosystems for stabilizing predator-prey interactions. The purpose of this research was to investigate the complexities of a discrete-time predator-prey system with a refuge effect. The analysis investigated the presence and stability of fixed points, as well as period-doubling and Neimark-Sacker (NS) bifurcations. The bifurcating and fluctuating behavior of the system was controlled via feedback and hybrid control methods. In addition, numerical simulations were performed as evidence to back up our theoretical findings. According to our findings, maintaining an optimal level of refuge availability was critical for predator and prey population cohabitation and stability.

An analysis of the stability and bifurcation of a discrete-time predator-prey model with the slow-fast effect on the predator.

In many environments, predators have significantly longer lives and meet several generations of prey, or the prey population reproduces rapidly. The slow-fast effect can best describe such predator-prey interactions. The slow-fast effect ε can be considered as the ratio between the predator's linear death rate and the prey's linear growth rate. This paper examines a slow-fast, discrete predator-prey interaction with prey refuge and herd behavior to reveal its complex dynamics. Our methodology employs the eigenvalues of the Jacobian matrix to examine the existence and local stability of fixed points in the model. Through the utilization of bifurcation theory and center manifold theory, it is demonstrated that the system undergoes period-doubling bifurcation and Neimark-Sacker bifurcation at the positive fixed point. The hybrid control method is utilized as a means of controlling the chaotic behavior that arises from these bifurcations. Moreover, numerical simulations are performed to demonstrate that they are consistent with analytical conclusions and to display the complexity of the model. At the interior fixed point, it is shown that the model undergoes a Neimark-Sacker bifurcation for larger values of the slow-fast effect parameter by using the slow-fast effect parameter ε as the bifurcation parameter. This is reasonable since a large ε implies an approximate equality in the predator's death rate and the prey's growth rate, automatically leading to the instability of the positive fixed point due to the slow-fast impact on the predator and the presence of prey refuge.

Passively Q-Switched Er-Doped Fiber Laser Based on Bentonite Clay (Al2H2O6Si) Saturable Absorber.

This paper presents the investigations toward the direct use of bentonite clay (Al2H2O6Si) nanoparticles to act like a saturable absorber (SA) for the Q-switched pulse operation of an erbium-doped fiber laser (EDFL). The measured results reveal that with the incorporation of bentonite clay nanopowder as a SA, an EDFL is realized with a Q-switching mechanism starting at a pump power of 30.8 mW, and a Q-switched emission wavelength was noticed at 1562.94 nm at 142 mW pump power. With an increased pump from 30.8 mW to 278.96 mW, the temporal pulse parameters including minimum pulse duration and maximum pulse repetition rates were reported as 2.6 µs and 103.6 kHz, respectively. The highest peak power, signal-to-noise ratio, output power and pulse energy were noticed to be 16.56 mW, 51 dB, 4.6 mW, and 47 nJ, respectively, at a highest pump power of 278.96 mW. This study highlights the significance of bentonite clay (Al2H2O6Si) nanoparticles as a potential candidate for a saturable absorber for achieving nonlinear photonics applications.

Perspectives on development and advancement of new tuberculosis vaccines.

Tuberculosis (TB) remains a leading cause of death worldwide and is estimated to have caused 1.3 million deaths worldwide in 2022. Approximately one quarter of the world's population are infected with Mycobacterium tuberculosis, of whom up to 10% will progress to developing active TB disease. Achieving the World Health Organization End TB Strategy targets of a 95% reduction in TB mortality and a 90% reduction in TB incidence worldwide by 2035 remains a daunting task. The continuing spread of multidrug-resistant TB adds another obstacle to achieving global TB control. Larger funding pledges coupled with technological advances have recently enabled the enhancement of TB vaccine development efforts. These are yielding a pipeline of over 17 products currently in different stages of clinical trials. Emerging promising phase I and II trial results and advancement to phase III trials have necessitated "vaccine preparedness" in parallel so that a smooth transition from any positive clinical trial result to phase IV evaluation and implementation into policy and practice can follow. Promotion of a human rights-based approach, which recognizes and upholds the fundamental rights of all affected by the disease, is essential to ensure universal access to quality TB vaccines, regardless of their background or personal circumstances.

Suturing Versus Adhesion for Mesh Fixation in Ventral Hernia Repair and Abdominal Wall Reconstruction: A Systematic Review and Network Meta-Analysis.

Abdominal wall reconstruction (AWR) is a surgical procedure performed to address various conditions such as hernias, incisional hernias, and complex abdominal wall defects. Mesh fixation plays a crucial role in providing mechanical reinforcement to the weakened abdominal wall during AWR. Traditionally, suturing has been the preferred method for mesh fixation; however, adhesion techniques using tissue adhesives or glues have gained attention as an alternative approach. This systematic review aims to compare suturing and adhesion techniques for mesh fixation in AWR and assess their effectiveness in preventing hernia recurrence. A comprehensive literature search was conducted across relevant databases, including PubMed, MEDLINE, Embase, and the Cochrane Library. Studies that fulfilled the predetermined eligibility criteria were included. The primary outcome measure of interest was hernia recurrence rates. Secondary outcomes included mesh-related complications, surgical site infections, patient-reported outcomes, and functional outcomes. A risk of bias assessment was performed for the included studies, and data were synthesized qualitatively. Overall, the results of the included studies suggest that atraumatic mesh fixation with glue may have the potential to reduce chronic groin pain (CGP). However, there were significant variations in patient selection criteria, glue administration techniques, and hernia repair methods among the trials, which limited the ability to draw definitive conclusions. Additionally, the definitions of CGP and measurement scales for postoperative pain varied across studies, making it challenging to compare outcomes. The limitations of the review include the small sample sizes in some trials, relatively short follow-up durations, and the lack of standardized criteria for assessing variables such as foreign body sensation and groin compliance. Furthermore, the economic implications of using glue fixation compared to traditional suture fixation need to be considered.

Q-switched pulse operation in erbium-doped fiber laser subject to zirconia (ZrO2) nanoparticles-based saturable absorber.

In this paper, the zirconia (ZrO2) nanoparticles-based saturable-absorber (SA) have been incorporated in an erbium-doped fiber laser (EDFL) cavity for achieving a Q-switched pulse operation. The implementation of the zirconia nanoparticles-based powder on the fiber facet was accomplished using the index-matching gel's adhesion effect. The incorporation of SA in the laser cavity yielded a stable and self-starting Q-switched operation under 19.36 mW pump power that corresponded to the emission wavelength of 1557.29 nm. Additionally, it was observed that the EDFL's emission wavelength tuned from 1557.29 nm to 1562.3 nm , and the repetition rates and pulse width ranged from 61.2 to 130 kHz and 7.9 to 3.6 µs, respectively, as the pump power was increased from 19.36 to 380.16 mW. Measured experimental results reveal that at a maximum pump power of 380.16 mW, the maximum average output power, peak power, and pulse energy were noticed to be 1.17 mW, 2.5 mW, and 9 nJ, respectively. A 52 dB suppression in side bands was found at a pump power of 380.16 mW. Moreover, the stability and threshold tolerance of the EDFL has also been discussed in detail. These findings suggest that nanoparticle-based saturable absorbers have potential applications in a pulsed source, making it easier to implement in fiber cavity-based systems.

CF-LIBS based elemental analysis of Saussurea simpsoniana medicinal plant: a study on roots, seeds, and leaves.

The plant Saussurea Simpsoniana, which has been used in traditional medicine for its biocompatibility and abundant nutrients, offers a wide range of remedies. Local communities effectively utilize medicines derived from the plant's roots to treat various ailments such as bronchitis, rheumatic pain, and abdominal and nervous disorders. In this study, we present an elemental analysis of the chemical composition (wt%) of this medicinal plant using the laser-induced breakdown spectroscopy (LIBS) technique. In the air atmosphere, an Nd:YAG (Q-switched) laser operating at a wavelength of 532 nm is utilized to create plasma on the sample's surface. This laser has a maximum pulse energy of approximately 400 mJ and a pulse duration of 5 ns. A set of six miniature spectrometers, covering the wavelength range of 220-970 nm, was utilized to capture and record the optical emissions emitted by the plasma. The qualitative analysis of LIBS revealed the presence of 13 major and minor elements, including Al, Ba, C, Ca, Fe, H, K, Li, Mg, Na, Si, Sr, and Ti. Quantitative analysis was performed using calibration-free laser-induced breakdown spectroscopy (CF-LIBS), ensuring local thermodynamical equilibrium (LTE) and optically thin plasma condition by considering plasma excitation temperature and electron number density. In addition, a comparison was made between the results obtained from CF-LIBS and those acquired through energy-dispersive X-ray spectroscopy (EDX) analysis.

Financial sanctions and environmental, social, and governance (ESG) performance: A comparative study of ownership responses in the Chinese context.

This study conducts a comprehensive examination of the relationships between strategic investors, financial sanctions, and ESG performance in non-financial Chinese firms from 2011 to 2022. Using data from ASSET4 and the Global Sanction Database (GSDB), the study reveals that government and foreign investors significantly promote ESG performance, while family investors have a negative impact. Moreover, the findings show distinct responses among government, foreign, and family investors when confronted with financial sanctions. Specifically, both foreign and family investors demonstrate an increased engagement in CSR activities during these periods. Conversely, government investors are linked to a decrease in ESG performance amidst financial sanctions. The results make significant contributions to the fields of ownership literature, agency theory, and sanctions literature. Additionally, they provide practical implications for diverse stakeholders, including investors, managers, and policymakers.

Exploring the economic impact of institutional entrepreneurship, social Innovation, and poverty reduction on carbon footprint in BRICS countries: what is the role of social enterprise?

The world is facing challenges to reduce carbon emissions, the complex interplay between socioeconomic dynamics and environmental sustainability is of utmost importance. In the context of the BRICS nations-Brazil, Russia, India, China, and South Africa-this study explores the intricate interactions between institutional entrepreneurship, institutional innovation, poverty reduction, social globalization, urbanization, and social entrepreneurship as well as their combined effects on the carbon footprint over the period of 1990 to 2021. This work examines the multi-dimensional interactions inside this nexus using a thorough analytical strategy that includes the Generalized Method of Moments (GMM), Three-Stage Least Squares (3SLS), and Robust regression approaches. Institutional entrepreneurship and innovation are the main forces behind institutional change and may have an impact on how people behave in terms of the environment. Strategies for reducing poverty frequently involve greater resource usage, which has an impact on carbon footprint. Examining social globalization's impact on carbon footprints is necessary given how it affects consumer habits and economic activity. Rapid urbanization is a dual problem because it spurs both increased energy demand and novel sustainability measures. With its emphasis on community-driven solutions, social entrepreneurship can provide regional solutions to reduce poverty and carbon emissions. The study's findings provide policymakers, practitioners, and researchers with insights into the complex web of socio-economic factors that underlies carbon footprint fluctuations. This research paves the way for informed policy decisions, sustainable business practices, and the pursuit of harmonious development that addresses both economic aspirations and environmental imperatives within the BRICS countries by illuminating the connections between institutional entrepreneurship, innovation, poverty reduction, social globalization, urbanization, social entrepreneurship, and carbon emissions.

Consumers' purchase decision in the context of western imported food products: Empirical evidence from Pakistan.

It is essential to identify consumer purchase behavior to establish and implement effective marketing strategies by Western food chains in Pakistan. By identifying motives, firms can offer extra-value products to their current and potential clients. Thus, this study seeks to understand what drives Pakistani consumers to buy imported Western food. This quantitative study uses A standardized structured questionnaire to collect data from 375 Karachi residents. The researchers use a convenient sampling strategy and analyze the data using PLS-SEM modeling through Smart-PLS 4.0. The findings of this research demonstrate that subjective norms, religiosity, product attributes, brand trust, customer satisfaction, and lifestyle significantly and positively influence consumer purchase intention. The findings also show that consumer purchase intention, lifestyle, and subjective norms significantly and positively correlate with purchase behavior. Finally, the study concludes that purchase intention significantly and positively mediates between exogenous and endogenous variables (purchase behavior). This research has significant theoretical and managerial implications. Local and international marketing professionals who wish to investigate the expanding consumer market in Pakistan can find the study's findings extremely useful. In addition, the outcomes of this research enrich the existing body of consumer behavior literature, which is helpful for future researchers.

Risk modelling of ESG (environmental, social, and governance), healthcare, and financial sectors.

Climate change poses enormous ecological, socio-economic, health, and financial challenges. A novel extreme value theory is employed in this study to model the risk to environmental, social, and governance (ESG), healthcare, and financial sectors and assess their downside risk, extreme systemic risk, and extreme spillover risk. We use a rich set of global daily data of exchange-traded funds (ETFs) from 1 July 1999 to 30 June 2022 in the case of healthcare and financial sectors and from 1 July 2007 to 30 June 2022 in the case of ESG sector. We find that the financial sector is the riskiest when we consider the tail index, tail quantile, and tail expected shortfall. However, the ESG sector exhibits the highest tail risk in the extreme environment when we consider a shock in the form of an ETF drop of 25% or 50%. The ESG sector poses the highest extreme systemic risk when a shock comes from China. Finally, we find that ESG and healthcare sectors have lower extreme spillover risk (contagion risk) compared to the financial sector. Our study seeks to provide valuable insights for developing sustainable economic, business, and financial strategies. To achieve this, we conduct a comprehensive risk assessment of the ESG, healthcare, and financial sectors, employing an innovative approach to risk modelling in response to ecological challenges.

Beyond physical health: the role of psychosocial challenges and stigma in tackling the COVID-19 pandemic-A scoping review.

Background: The socio-cultural response to the Coronavirus Disease 2019 (COVID-19) and the level of adherence to evidence-based guidelines played a crucial role in determining the morbidity and mortality outcomes during the pandemic. This review aims to evaluate the impact of stigma and psycho-socio-cultural challenges on efforts to control the COVID-19 pandemic and to identify ways to mitigate such challenges in future pandemics. Methods: Using keywords including COVID-19, coronavirus, stigma, psychosocial challenges, and others, the authors searched seven major databases with a time limitation of July 2021, which yielded 2,038 results. Out of these, 15 papers were included in this review. Results: The findings of the review indicated that several psychosocial, socio-economic, and ethno-cultural factors are linked to the transmission and control of COVID-19. The research revealed that stigma and related psychosocial challenges and others, such as anxiety, fear, and stigma-driven social isolation, have resulted in significant mental health problems. Discussion: The review underscores the negative impact of stigma on COVID-19 patients, survivors, and the general population. Addressing stigma and psychosocial challenges is crucial to effectively manage the current pandemic and to prevent similar challenges during future public health crises.

Assessing the environmental impacts of renewable energy sources: A case study on air pollution and carbon emissions in China.

This study investigates the impact of renewable and non-renewable energy sources on carbon emissions in the context of China's 14th Five-Year Plan (2021-2025). The plan emphasises a "Dual-control" strategy of simultaneously setting energy consumption limits and reducing energy intensity for GDP (gross domestic product) in order to meet the targets of the five-year plan. Using a comprehensive dataset of Chinese energy and macroeconomic information spanning from 1990 to 2022, we conduct a Granger causality analysis to explore the relationship between energy sources and the level of air pollution. Our findings reveal a unidirectional link, wherein renewable energy contributes to a reduction in air pollution, while non-renewable energy sources lead to an increase. Despite the government's investment in renewable energy, our results show that China's economy remains heavily reliant on traditional energy sources (e.g., fossil fuels). This research is the first systematic examination of the interplay between energy usage and carbon emissions in the Chinese context. Our findings provide valuable insights for policy and market strategies aimed at promoting carbon neutrality and driving technological advancements in both government and industries.

Radiological risk assessment from the Gamma spectrometry of soil samples in the vicinity of a research centre in Nilore, Pakistan.

Measurements of radionuclides' activities in air, water, and soil give clues about the anthropogenic activities in the region, and imperative to assess the overall radiological risk for individuals. Such an investigation was carried out to characterize the soil activities in the region hosting a research center, and to calculate the associated elements of radiological risk in terms of radiation doses and hazard indices. The soil samples were collected within the radius of 10 km in local area, Nilore, and analysed for activity using a high-purity germanium (HPGe) gamma spectrometric system. In all samples, only the basic nuclides, contributing to terrestrial activity, i.e., 40 K, 232Th, 226Ra, and 137Cs, were observed within the detectable limits of activity. The distribution of the data set and the correlation between the measured activities were studied with the use of the principal component analysis (PCA). The measured average specific activities of 226Ra, 232Th, 40 K, and 137Cs were 40.65 ± 9.84 Bq/kg, 59.31 ± 16.53 Bq/kg, 528.24 ± 131.18 Bq/kg, and 5.16 ± 4.56 Bq/kg respectively. The corresponding dose rate in air was found to be 76.63 ± 18.39 nGy/h, which is slightly higher than the world median value of 51 nGy/h calculated from concentration of terrestrial radionuclides in soil but falls within the world average value range of outdoor external exposure of 18-93 nGy/h obtained through direct measurement, and therefore not harmful for the living species. The standard hazard indices for all soil samples such as radium equivalent activity ([Formula: see text]), external hazard index (Hex), and internal hazard index (Hin) were also found within safe limits for the soil to be used as construction of building material. This investigation led to conclusion that the soil activities are consistent with the usual background level of terrestrial activities, and their associated dose rates are well within the safe limits for public.

Virulence and transgenerational effects of Metarhizium anisopliae on Oxycarenus hyalinipennis.

BACKGROUND: Insect pests cause major yield losses to Gossypium hirsutum, often requiring the use of chemical insecticides. To avoid human health, environmental and resistance problems, entomopathogenic fungi (EPF) can be used to control insect pests. In our study, the pathogenicity of Metarhizium anisopliae to Oxycarenus hyalinipennis was determined by the immersion method. Furthermore, the sublethal and lethal effects of M. anisopliae on the biological parameters of O. hyalinipennis were investigated by age-stage, two-sex life table software. RESULTS: M. anisopliae infection was lethal to the fourth instar of O. hyalinipennis with LC50 values of 8.84 × 104 spores mL-1 . The sublethal and lethal concentrations of M. anisopliae not only affected the parental generation (F0 ) but also the demographic parameters of the offspring of the filial generation (F1 ). Transgenerational results of F1 infected with M. anisopliae showed decreased net reproductive rate (R0 ), intrinsic rate of increase (r) and mean generation time (T) compared to those of the control group. The larval developmental duration significantly decreased to 15.52 and 19.02 days in the LC50 and LC20 groups, respectively, compared to 21.08 days in the control group. There was a noteworthy decline in mean fecundity in the LC50 and LC20 groups, i.e., 16.0 and 20.96 eggs, compared to 33.26 eggs in the control group. Adult longevity was likewise considerably reduced in the LC50 and LC20 treated groups. CONCLUSION: The study showed that M. anisopliae can have an enduring impact on the biological parameters of O. hyalinipennis, which may enhance its use in eco-friendly management programs. © 2023 Society of Chemical Industry.

A mutagenesis study of autoantigen optimization for potential T1D vaccine design.

A previously reported autoreactive antigen, termed the X-idiotype, isolated from a unique cell population in Type 1 diabetes (T1D) patients, was found to stimulate their CD4+ T cells. This antigen was previously determined to bind more favorably than insulin and its mimic (insulin superagonist) to HLA-DQ8, supporting its strong role in CD4+ T cell activation. In this work, we probed HLA-X-idiotype-TCR binding and designed enhanced-reactive pHLA-TCR antigens using an in silico mutagenesis approach which we functionally validated by cell proliferation assays and flow cytometry. From a combination of single, double, and swap mutations, we identified antigen-binding sites p4 and p6 as potential mutation sites for HLA binding affinity enhancement. Site p6 is revealed to favor smaller but more hydrophobic residues than the native tyrosine, such as valine (Y6V) and isoleucine (Y6I), indicating a steric mechanism in binding affinity improvement. Meanwhile, site p4 methionine mutation to hydrophobic residues isoleucine (M4I) or leucine (M4L) modestly increases HLA binding affinity. Select p6 mutations to cysteine (Y6C) or isoleucine (Y6I) exhibit favorable TCR binding affinities, while a swap p5-p6 tyrosine-valine double mutant (V5Y_Y6V) and a p6-p7 glutamine-glutamine double mutant (Y6Q_Y7Q) exhibit enhanced HLA binding affinity but weakened TCR affinity. This work holds relevance to potential T1D antigen-based vaccine design and optimization.

Lost in transition: a case report of very late palliation of a double outlet right ventricle.

Background: Children with congenital heart disease remain at risk of being lost to follow-up. They may present at a later stage with complications related to underlying condition that usually require in-depth phenotyping for optimal management. We describe an unusual case of a double outlet right ventricle (DORV) who presented three decades after initial intervention. Case summary: A 32-year-old female sought attention for worsening breathlessness. Available data suggested that she had double outlet right ventricle (DORV) and underwent pulmonary artery (PA) banding in infancy. On examination, she was frail, clubbed and cyanosed with oxygen saturation reduced to 75% at rest. Blood tests demonstrated elevated haemoglobin (208 g/L) and thrombocytopenia (70 *109/L). Echocardiography was limited but demonstrated DORV with increased gradient across both outflow tracts. Cardiac magnetic resonance (CMR) imaging clearly demonstrated DORV with doubly committed interventricular communication, subvalvular aortic valve stenosis and supravalvular pulmonary stenosis due to a previous PA band. CMR was also remarkable for demonstrating severely impaired left ventricle and difficulty achieving optimal contrast between myocardium and blood pool on late enhancement images. She underwent relief of subaortic stenosis with immediate improvement in left ventricular (LV) function and PA plasty with application of a new PA band. Conclusion: Lost to follow-up congenital patients present a particular challenge due to complications of chronic unusual physiology. This requires careful assessment by a multidisciplinary team to define optimal management strategy.

The role of green innovation on environmental and organizational performance: Moderation of human resource practices and management commitment.

Green innovation is an essential and burning topic for environmental and organizational performance. Therefore, this research aims to examine the effect of green innovation on environmental performance, which leads to organizational performance. Another objective is to measure the impact of two dimensions of green innovation, such as green process & green product measures, on green innovation. The second prime aim of this research is to evaluate the moderation of management commitment & human resource practices in an association between green innovation and organizational & environmental performance. A total of 320 employees provided their perspectives on a self-administrated questionnaire from the textile industry of Pakistan. We have employed SEM-based multivariate modeling to examine the data. This research has measured the reflective indicators measurement model through confirmatory factor analysis, an obvious choice of structural equation modeling to examine observed and unobserved variables and indicators using PLS-SEM (partial least square-structural equation modeling). The research findings reveal a positive & significant effect of product & process innovation on green innovation. Further, green innovation significantly impacts environmental and organizational performance. A two-way interaction (moderation) of human resource practices & green innovation does not have a cogent moderating effect on organizational & environmental performance. However, management commitment has a significant moderation between green innovation & organizational performance. A three-way interaction (moderated moderation) model finds a substantial effect on organizational attainment but an insignificant impact on environmental performance. The research outcomes significantly contribute and suggest that practitioners and policymakers must institutionalize green innovation practices in their organizations to enhance their organizational and environmental performance. HR practitioners play a vibrant role in creating green norms and organizational culture. The study findings also suggest that management commitment to green innovation advocates organization-level transformations toward adopting green practices.

Genotypic distribution of human papillomavirus and phylogenetic analysis of E6 and E7 gene of HR-HPV variants isolated from Pakistani population.

High-risk-human papillomavirus (HR-HPV)-induced cervical cancer is the second most common cause of death among females worldwide. HPV16 is the most prevalent HR-HPV infection worldwide. This study found the genotypic distribution of HR-HPV in the local population and investigated the sequence variations among the E6 and E7 oncogenes of the local HPV16 genotype to the E6 and E7 oncogenes of the foreign HPV16 genotypes and constructed a phylogenetic relationship based on nucleotide sequence comparison among the variants identified in our study along with previously reported isolates that were obtained from different regions of the world. The samples were collected from patients with cervical cancer. Genomic DNA was extracted, and HR-HPV genotypes were determined using real-time PCR. The HPV16 E6 and E7 genes were amplified and sequenced. A HPV16 phylogenetic tree was constructed using the maximum likelihood method with MEGA 7. HPV16 was the most prevalent human papillomavirus (HPV) type identified in the present study. HPV16 isolates belonged to the A1 sublineage of the European branch. Twenty-one nucleotide sequences were included in this analysis. The first, second, and third codon positions are also included. The final dataset included 776 positions.