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Aims: To evaluate the safety profile of robotic cholecystectomy performed within the United Kingdom (UK) Robotic Hepatopancreatobiliary (HPB) training programme. Methods: A retrospective evaluation of prospectively collected data from eleven centres participating in the UK Robotic HPB training programme was conducted. All adult patients undergoing robotic cholecystectomy for symptomatic gallstone disease or gallbladder polyp were considered. Bile duct injury, conversion to open procedure, conversion to subtotal cholecystectomy, length of hospital stay, 30-day re-admission, and post-operative complications were the evaluated outcome parameters. Results: A total of 600 patients were included. The median age was 53 (IQR 65–41) years and the majority (72.7%; 436/600) were female. The main indications for robotic cholecystectomy were biliary colic (55.5%, 333/600), cholecystitis (18.8%, 113/600), gallbladder polyps (7.7%, 46/600), and pancreatitis (6.2%, 37/600). The median length of stay was 0 (IQR 0–1) days. Of the included patients, 88.5% (531/600) were discharged on the day of procedure with 30-day re-admission rate of 5.5% (33/600). There were no bile duct injuries and the rate of conversion to open was 0.8% (5/600) with subtotal cholecystectomy rate of 0.8% (5/600). Conclusion: The current study confirms that robotic cholecystectomy can be safely implemented to routine practice with a low risk of bile duct injury, low bile leak rate, low conversion to open surgery, and low need for subtotal cholecystectomy. [ABSTRACT FROM AUTHOR]

The corrosion protection of aluminum alloys is severely compromised by marine environments, demanding the formulation of efficient protective coatings. Epoxy resin, diglycidyl ether of bisphenol A (DGEBA), and curing agent diethylenetriamine (DETA) were used with the mixing ratio of 100:12 to synthesize functionalized SiO2/GO-based composite coatings and investigate the corrosion protection efficacy for aluminum alloy AA6061 in marine environments. To boost the coatings' barrier and anticorrosive attributes, functionalized silica (FSiO2, with 0, 3, 6, 9, 12, and 15 wt%) and graphene oxide (GO) were jointly incorporated into the DGEBA/DETA epoxy-hardener system for producing composite coatings. The functionalization of silica particles using 3-aminopropyl-triethoxysilane and synthesis of GO was successfully carried out, according to the Fourier transform infrared spectroscopy evidence. The structural properties were investigated by X-ray diffraction. The hydrophobicity tests were conducted for the measurement of the contact angles. The highest static contact angle (126° ± 2) and the lowest contact angle (74° ± 1.5) were recorded for the sample EHS9GO2 and AA6061, respectively, which showed that EHS9GO2 coating had the most hydrophobic behavior. An adhesion test (method B, tape test) was performed on prepared coatings to check the quality of adhesion with the substrate aluminum alloy AA6061. The neat epoxy coating (EHS0GO0) displayed a fair adhesion rating of 3B, while EHS9GO2 coating exhibited excellent adhesion (5B) with substrate AA6061. Furthermore, electrochemical impedance spectroscopy and potentiodynamic polarization tests were employed for assessing the electrochemical behavior and anticorrosion performance of the prepared coatings. It was observed from the Bode plot, that the impedance magnitude/modulus for EHS9GO2 at lower frequencies was the highest as compared to other samples during immersion in the artificial seawater. The bare aluminum alloy substrate AA6061 had the highest corrosion rate of value 0.10483 ± 0.00198 mm/year, due to the direct contact with the electrolyte. Moreover, the highest value of Ecorr (356 ± 0.42 mV) and lowest values of Icorr (0.18 ± 0.03µA), βa (48.7 ± 2 mV/decade), and βc (28.8 ± 1 mV/decade) were witnessed for EHS9GO2 coating, showing significant anticorrosion efficiency against the corrosive electrolyte. [ABSTRACT FROM AUTHOR]

In this study effect of Ni single-layer coating and Ni/Cr bilayer coating on room temperature corrosion of Sm2Co17 substrate in 3.5wt% NaCl solution was extensively performed. However, severe pitting corrosion occurred to the bare Sm2Co17 substrate and resulted in formation of cracks. Ni coating had good adhesion to the Sm2Co17 substrate but could not effectively improve the corrosion resistance of the substrate due to its porous nature. The Ni/Cr bilayer-coated magnet exhibited excellent corrosion resistance due to the prevention of Cl− ions penetration by the Cr coating. Additionally, no prominent negative effect on magnetic properties was evidenced after Ni or Ni/Cr coating. Hence, based on above-mentioned outcome Ni/Cr coating above Sm2Co17 magnet is potentially recommended to mitigate the corrosion problem of permanent magnets operating in marine conditions. [ABSTRACT FROM AUTHOR]

Understanding of climate change's effects on high-altitude regions is crucial for devising effective mitigation and adaptation strategies. Through a mixed research approach, we investigated the impact of climate change on remote mountain communities in Pakistan, focusing on nine villages in Gilgit-Baltistan. Our findings highlight the vulnerability of these communities to severe climate events such as landslides, flash floods, and glacial lake outburst floods, which have significantly disrupted agricultural activities and other livelihood options, leading to a decline in household food security. The study revealed that livestock rearing and traditional agricultural practices constitute the primary sources of income for these households. However, these practices have been experiencing declining productivity, necessitating the increasing reliance on external markets to meet food demands. In response to these pressing issues, our research strongly advocates for the revival of traditional irrigation systems within these villages. Reviving these systems holds the potential to rejuvenate local food production and reduce reliance on external markets. To achieve this vision, a collaborative effort involving both private enterprises and government bodies is essential, incorporating innovative and climate-resilient irrigation techniques. Additionally, our research emphasizes the promising opportunities presented by Yak husbandry and Sea buckthorn cultivation. These alternative income sources could provide sustainable livelihoods for households in these regions, diversifying their economic base and reducing their dependence on traditional agricultural practices. [ABSTRACT FROM AUTHOR]

The multi-objective grasshopper optimization algorithm (MOGOA) is a relatively new algorithm inspired by the collective behavior of grasshoppers, which aims to solve multi-objective optimization problems in IoT applications. In order to enhance its performance and improve global convergence speed, the algorithm integrates simulated annealing (SA). Simulated annealing is a metaheuristic algorithm that is commonly used to improve the search capability of optimization algorithms. In the case of MOGOA, simulated annealing is integrated by employing symmetric perturbation to control the movement of grasshoppers. This helps in effectively balancing exploration and exploitation, leading to better convergence and improved performance. The paper proposes two hybrid algorithms based on MOGOA, which utilize simulated annealing for solving multi-objective optimization problems. One of these hybrid algorithms combines chaotic maps with simulated annealing and MOGOA. The purpose of incorporating simulated annealing and chaotic maps is to address the issue of slow convergence and enhance exploitation by searching high-quality regions identified by MOGOA. Experimental evaluations were conducted on thirteen different benchmark functions to assess the performance of the proposed algorithms. The results demonstrated that the introduction of simulated annealing significantly improved the convergence of MOGOA. Specifically, the IDG (Inverse Distance Generational distance) values for benchmark functions ZDT1, ZDT2, and ZDT3 were smaller than the IDG values obtained by using MOGOA alone, indicating better performance in terms of convergence. Overall, the proposed algorithms exhibit promise in solving multi-objective optimization problems. [ABSTRACT FROM AUTHOR]

In every society, there exist disadvantaged groups who have failed constantly to take part in the development of the economy and reap the benefits of economic growth as well. Along with economic and social factors, environmental factors are also accountable in making inclusion a challenge for the marginalized group. Contaminated drinking water, inappropriate sanitation systems, and pollution are the factors that affect health and wellbeing of the poor class by affecting their productivity. Thus, the lack of a clean environment leads the poor section towards further poverty and income inequality. Since the 2030 Agenda for Sustainable Development emphasizes three components to achieve sustainable development, namely economic, social, and environmental, this study inspects the role of macroeconomic policies in ensuring an inclusive clean environment in developing countries. Moreover, it considers the composite effect of fiscal policy and monetary policy on environmental inclusion by including interactive terms. This investigation uses FE-2SLS on a panel of 51 developing countries for the period of 1995–2019 to analyse the impact of macroeconomic policies on environmental inclusion. The study provides empirical evidence that fiscal and monetary policy has the potential to ensure an inclusive clean environment in developing countries. The findings imply that the macroeconomic policy actions depend on each other. Furthermore, governments in developing regions are required to cut nondeveloping expenditures and use expansionary monetary policy to promote green growth. [ABSTRACT FROM AUTHOR]

The land use land cover (LULC) change due to the rapidly growing population is a common feature of the urban area. The rapidly growing population in Malakand Division is a greater threat to the LULC of the area due to its negative impact on environment and ecology. This research aims to detect the variations in LULC from 1991 to 2017 in the Malakand Division, Khyber Pakhtunkhwa (KP) province of Pakistan. The study relies on secondary dataset downloaded from the US Geological Survey (1991, 2001, 2011, and 2017 imageries) and the United Nations Office for the Coordination of Humanitarian Affairs (UN OCHA) website. Maximum likelihood technique under supervised image classification was opted to analyze the LULC changes in between 1991 and 2017. The results were based on six major land use classes including agriculture built-up area, vegetation cover, water bodies, snow cover, and barren land. The results from 1991 to 2017 show a substantial reduction in snow cover and barren land which is consequence of climate change. A known change has been recorded in built-up area which shows an increase from 1.02 to 6.2% with a change of 5.18% of the total land. The vegetation cover water bodies were also showing increase in area. The vegetation cover increased from 28.89 to 44.67% while barren land decreased from 45.68 to 40.29% of the total area. Furthermore, the built-up area increased from 1.02 to 6.2%, whereas water covers increased from 0.63% (1991) to 0.86% (2017) of the total area. The study concludes that there is an immense need for planning to preserve the natural habitat for sustainable development in the area. [ABSTRACT FROM AUTHOR]

Cultural ecosystem services are the non-material benefits that people obtain from ecosystems and these services are subject to tremendous anthropogenic and climatic pressures. This study evaluates the spatiotemporal economic valuation of selected cultural and natural landscapes in Pakistan using net present value method. The results indicate that both cultural landscapes and mountain ecosystems are the most significant contributors to Pakistan's cultural ecosystem services. The net present value of our study area was USD 96/ha, while this value is ranged from USD 0.000242/ha to USD 138,997/ha in the 42 previous studies selected for comparison. Service flow, population, and visitor numbers were the most significant indicators of cultural ecosystem services. The promotion of cultural ecosystem services as an inclusive service and the application of discounted rates are identified as key approaches for ensuring sustainable resource use and enhanced intergenerational benefits by incorporating cultural ecosystem services into the national policy framework. [ABSTRACT FROM AUTHOR]

Throughout the world, livestock predation by mammalian carnivores causes significant economic losses to poor farmers, and leads to human–wildlife conflicts. These conflicts result in a negative attitude towards carnivore conservation and often trigger retaliatory killing. In northern Pakistan, we investigated livestock depredation by large carnivores between 2014 and 2019, and subsequent Human–wildlife conflict, through questionnaire-based surveys (n = 100 households). We used a semi-structured questionnaire to collect data on livestock population, depredation patterns, predation count, and conservation approaches. We found a statistically significant increasing pattern of predation with influential factors such as age, gender, occupation, education of respondents, population of predators, threats index for predators and conservation efforts. Some 310 livestock heads with an average of 51 animals per year out of the total 9273 heads were killed by predators, and among them 168 (54%) were attributed to the wolf and 142 (45.8%) to snow leopard. Major threats to carnivores in the area included retaliatory killing, habitat destruction and climate change. Incentivization against depredation losses, guarded grazing and construction of predator-proof corral may reduce Human–wildlife conflict and both livelihood and predator can be safeguarded in the study area. [ABSTRACT FROM AUTHOR]

This study presents part-II of the work-in-progress for the development of a high-speed wind tunnel under the EU Commission (ERDF) project. This study was carried out after the inlet section of the supersonic wind tunnel prototype had been designed in part-I [1] by introducing a simplified design approach of "table of inclination". The design optimization of the exhaust section, i.e., diffuser of the wind tunnel is the main objective of the current study. Diffuser design optimization was carried out in three steps; at first, the selection of the diffuser type was carried out and the initial estimated design was created. In the next step, 2D optimization of the wind tunnel design was carried out, and finally, 3D optimization of the complete wind tunnel model was performed. The main geometric parameters of diffuser design were optimized using CFD analysis. Due to the proposed design optimization strategy, the conventionally long diffuser length was successfully reduced. Additionally, 3D optimization further improved the design and helped to resolve the problem of higher operating power. This compact wind tunnel duct will have relatively lower manufacturing costs as well as the overall testing facility will occupy a smaller space. The optimized design of the diffuser and its integration with the inlet section of the wind tunnel marked the completion of the design of the full wind tunnel duct. [ABSTRACT FROM AUTHOR]

This study aims to develop a simplified approach for the design of high-speed wind tunnels, operating within the range of Mach 1-4. The study is conducted in two stages; design stage-I consists of the basic parts of a high-speed wind tunnel, i.e. test section and nozzle throat sizes along with the calculations of the minimum pressure ratios necessary for the starting and running of the wind tunnel. Design stage-II is the aerodynamic design of the inlet nozzle contour with the focus on the divergent nozzle section only. In this stage, the fundamental method of characteristics (MOC) is employed by using region-to-region solution approach. Due to the long and complicated procedure of classical MOC, a simpler approach of "table of inclination" is proposed. This inclination table approach is simple in use, highly precise, and efficient which reduces more than 75 % of the calculation time of the MOC. Validation of the nozzle contour design is performed with the Area-Mach ratio relation followed by the results verification obtained from the MATLAB programming. The contour design results of the study are highly accurate (less than 1 % error) which manifests the future possible significance of the inclination table approach for supersonic wind tunnel designs. [ABSTRACT FROM AUTHOR]

Novel robustness and performance parameters are established for Smooth Super Twisting Algorithm (SSTA). The stability of SSTA is well established for arbitrary gains using homogeneity approach. The design and tuning of the controller parameters is a major issue and no analytic design method is available so far. A novel Lyapunov function is proposed and by the virtue of stability analysis, the stability bounds for a certain class of uncertainties are determined. In addition, the issue of finite time convergence is also explored, resulting in determination of the settling time as a function of the controller parameters. The proposed settling time formulation suggests a methodical approach to SSTA design in contrast to the available rules of thumb. Unlike the literature available for Higher Order Sliding Mode (HOSM) controllers, the proposed design framework is validated against a challenging problem of the Underground Coal Gasification (UCG) process control. Like the other process control problems the chosen problem is nonlinear and contains significant uncertainties. [ABSTRACT FROM AUTHOR]

Azoarcus sp. strain BH72, a mutualistic endophyte of rice and other grasses, is of agrobiotechnological interest because it supplies biologically fixed nitrogen to its host and colonizes plants in remarkably high numbers without eliciting disease symptoms. The complete genome sequence is 4,376,040-bp long and contains 3,992 predicted protein-coding sequences. Genome comparison with the Azoarcus-related soil bacterium strain EbN1 revealed a surprisingly low degree of synteny. Coding sequences involved in the synthesis of surface components potentially important for plant-microbe interactions were more closely related to those of plant-associated bacteria. Strain BH72 appears to be 'disarmed' compared to plant pathogens, having only a few enzymes that degrade plant cell walls; it lacks type III and IV secretion systems, related toxins and an N-acyl homoserine lactones–based communication system. The genome contains remarkably few mobile elements, indicating a low rate of recent gene transfer that is presumably due to adaptation to a stable, low-stress microenvironment. [ABSTRACT FROM AUTHOR]

Background: Left ventricular (LV) ejection fraction (EF) is a powerful prognostic predictor in patients with heart disease. However, LVEF calculated by 2-dimensional (2D) modalities such as echocardiography by use of the "modified" Simpson's rule may be incorrect in patients with regional dyssynchrony, presumably because regions of dyssynchrony are excluded from analysis.Methods and Results: To elucidate the difference between 2D and 3-dimensional (3D) methods with regard to LVEF calculation in patients with regional dyssynchrony, we compared LVEF derived from 8-frame gated technetium 99m sestamibi stress perfusion tomograms using commercially available 2D single photon emission computed tomography (SPECTEF) software that uses the modified Simpson's rule, 3D QGS, and investigational 3D p-FAST software in 136 left bundle branch block patients. Twenty-four patients had normal wall motion, whereas one hundred twelve showed septal dyssynchrony. Bland-Altman plots demonstrated that compared with QGS and p-FAST, SPECTEF overestimated LVEF in patients with septal dyssynchrony systemically by 8.6% and 11.3%, respectively.Conclusions: We conclude that compared with 3D modalities, 2D modalities that use the modified Simpson's rule, such as SPECT EF, overestimate LVEF in patients with dyssynchronous septal wall motion. Therefore 3D modalities are preferred to evaluate patients with regional dyssynchrony. [ABSTRACT FROM AUTHOR]

Objectives: Septal wall motion abnormalities are frequently observed in patients with left bundle branch block (LBBB). However, septal wall thickening in LBBB patients has not been thoroughly evaluated.Methods and Results: To investigate the relationship between septal wall motion and wall thickening, we studied 31 normal control subjects, 24 LBBB patients with normal wall motion (LBBB-NWM), and 24 LBBB patients with septal dyssynchrony (LBBB-SDS), all with a low likelihood (<15%) of coronary artery disease. The septal and lateral quadrants of the left ventricle were analyzed in stress 8-frame gated technetium 99m sestamibi tomograms. The percent wall thickening was calculated by use of a 25-segment polar map with the p-FAST software program by two independent methods: the regional count density increase from end diastole to end systole (CD method) and the geometric increase in the distance between the 50% thresholded endocardial and epicardial borders from end diastole to end systole (GD method). In addition, the ratio of septal/lateral percent wall thickening was calculated. The relative septal wall thickening in the entire LBBB population was decreased as compared with the normal control subjects (0.35 +/- 0.37 vs 0.81 +/- 0.17, P <.001). Decreased wall thickening was observed in not only LBBB-SDS patients but also to a lesser degree in LBBB-NWM patients (0.12 +/- 0.35, P <.001; 0.57 +/- 0.24, P =.005, respectively). This abnormality was most apparent when the CD method was used.Conclusions: Septal wall thickening is decreased in patients with LBBB even with normal wall motion. LBBB per se may compromise septal wall thickening, and dyssynchronous wall motion results in further deterioration of wall thickening. [ABSTRACT FROM AUTHOR]

Studies the concentration of lead in particulate deposits and in leaves of roadside plants in Karachi, Pakistan. Correlation between the number of passing petrol-driven vehicles and lead concentration in particulate deposits; Relationship between concentration of lead in the particulate deposits and lead accumulated by the leaves; Maximum lead accumulated by leaves of the roadside plants.

This study constructs and examines the dynamics of theoretical and atheoretical measures of global liquidity, using monthly data on the components of broad money over the period 2001 M12-2017 M12 for 39 high income countries. We group the countries into five regional blocks as categorized by the World Bank: East Asia and the Pacific, Europe and Central Asia, Latin America and the Caribbean, Middle East and North Africa, and North America. The atheoretical measures exploited by this study comprise of the simple-sum, GDP-weighted growth rates and PCA based aggregation methods; whereas theoretical measures include the currency equivalent and Divisia index techniques of monetary aggregation. We employ a graphical approach to investigate the trends and dynamics of the aggregates overtime, and a cross-correlation between cyclical components of global real economic activity and the lag of cyclical components of the measures of global liquidity to gauge the strength of their associations. The findings of this study reveal that theoretical measures outperform atheoretical ones in effective delineation of financial and liquidity conditions, and policy stance. Their cyclical components are also strongly associated with those of global real business activity. The currency equivalent measure, besides being a leading indicator of the shift in policy stance, has a sturdy association with global real business activity. Moreover, the theoretical measures, as noted by some empirical studies, contain some information content that the atheoretical lack. [ABSTRACT FROM AUTHOR]

Verapamil is a calcium channel blocker and highly effective in the treatment of hypertension, angina pectoris, and other diseases. However, the drug has a low bioavailability of 20 to 35% due to the first pass effect. The main objective of this study was to develop hybrid verapamil-dextran nanostructured lipid carriers (HVD-NLCs) in an attempt to increase verapamil cellular uptake. The formulations were successfully prepared by a high-shear homogenization method and statistically optimized using 24 full factorial design. The HVD-NLCs formulations were freeze-dried using trehalose as a cryoprotectant. The results showed that the optimized formula (VER-9) possessed a particle size (PS), polydispersity index (PDI), and the percentage of entrapment efficiency (%EE) of 192.29 ± 2.98, 0.553 ± 0.075, and 93.26 ± 2.66%, respectively. The incorporation of dextran sulfate in the formulation had prolonged the release of verapamil (~ 85% in 48 h) in the simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 6.8). The differential scanning calorimetry analysis showed no chemical interaction between verapamil and the excipients in the formulation. While wide-angle X-ray scattering studies demonstrated the drug in the amorphous form after the incorporation in the NLCs. The transmission electron microscopy and scanning electron microscopy images revealed that the nanoparticles had spherical shape. The cellular uptake study using Caco-2 cell line showed a higher verapamil uptake from HVD-NLCs as compared to verapamil solution and verapamil-dextran complex. The optimized formulation (VER-9) stored in the refrigerated condition (5 °C ± 3 °C) was stable for 6 months. In conclusion, the HVD-NLCs were potential carriers for verapamil as they significantly enhanced the cellular uptake of the drug. [ABSTRACT FROM AUTHOR]

A correction to the article "Complete Genome of the Mutualistic, N2-Fixing Grass Endophyte Azoarcus sp. Strain BH72" that was published in the 2006 issue is presented.