2D MXene Ti3C2Tx Enhanced Plasmonic Absorption in Metasurface for Terahertz Shielding

With the advancement of technology, shielding for terahertz (THz) electronic and communication equipment is increasingly important. The metamaterial absorption technique is mostly used to shield electromagnetic interference (EMI) in THz sensing technologies. The most widely used THz metamaterial absorbers suffer from their narrowband properties and the involvement of complex fabrication techniques. Materials with multifunctional properties, such as adjustable conductivity, broad bandwidth, high flexibility, and robustness, are driving future development to meet THz shielding applications. In this article, a theoretical simulation approach based on finite difference time domain (FDTD) is utilized to study the absorption and shielding characteristics of a two-dimensional (2D) MXene Ti3C2Tx metasurface absorber in the THz band. The proposed metamaterial structure is made up of a square-shaped array of MXene that is 50 nm thick and is placed on top of a silicon substrate. The bottom surface of the silicon is metalized with gold to reduce the transmission and ultimately enhance the absorption at 1–3 THz. The symmetric adjacent space between the MXene array results in a widening of bandwidth. The proposed metasurface achieves 96% absorption under normal illumination of the incident source and acquires an average of 25 dB shielding at 1 THz bandwidth, with the peak shielding reaching 65 dB. The results show that 2D MXene-based stacked metasurfaces can be proven in the realization of low-cost devices for THz shielding and sensing applications

An Application of Artificial Intelligence for the Joint Estimation of Amplitude and Two-Dimensional Direction of Arrival of Far Field Sources Using 2-L-Shape Array

An easy and efficient approach, based on artificial intelligence technique, is proposed to jointly estimate the amplitude, elevation, and azimuth angles of far field sources impinging on 2-L-shape array. In these proposed artificial intelligence techniques, the metaheuristics based on genetic algorithm and simulated annealing are used as global optimizers assisted with rapid local version of pattern search for optimization of the adaptive parameters. The performance metric is employed on a fitness evaluation function depending on mean square error which is optimum and requires single snapshot to converge. The proposed approaches are easy to understand, and simple to implement; the genetic algorithm specifically hybridized with pattern search generates fairly good results. The comparison of the given schemes is carried out with 1-L-shape array, as well as, with parallel-shape array and is found to be in good agreement in terms of accuracy, convergence rate, computational complexity, and mean square error. The effectiveness and efficiency of the given schemes are examined through Monte Carlo simulations and their inclusive statistical analysis

A new color image encryption technique using DNA computing and Chaos-based substitution box

In many cases, images contain sensitive information and patterns that require secure processing to avoid risk. It can be accessed by unauthorized users who can illegally exploit them to threaten the safety of people’s life and property. Protecting the privacies of the images has quickly become one of the biggest obstacles that prevent further exploration of image data. In this paper, we propose a novel privacy-preserving scheme to protect sensitive information within images. The proposed approach combines deoxyribonucleic acid (DNA) sequencing code, Arnold transformation (AT), and a chaotic dynamical system to construct an initial S-box. Various tests have been conducted to validate the randomness of this newly constructed S-box. These tests include National Institute of Standards and Technology (NIST) analysis, histogram analysis (HA), nonlinearity analysis (NL), strict avalanche criterion (SAC), bit independence criterion (BIC), bit independence criterion strict avalanche criterion (BIC-SAC), bit independence criterion nonlinearity (BIC-NL), equiprobable input/output XOR distribution, and linear approximation probability (LP). The proposed scheme possesses higher security wit NL = 103.75, SAC ≈ 0.5 and LP = 0.1560. Other tests such as BIC-SAC and BIC-NL calculated values are 0.4960 and 112.35, respectively. The results show that the proposed scheme has a strong ability to resist many attacks. Furthermore, the achieved results are compared to existing state-of-the-art methods. The comparison results further demonstrate the effectiveness of the proposed algorithm

Deep eutectic solvent coated cerium oxide nanoparticles based polysulfone membrane to mitigate environmental toxicology

In this study, ceria nanoparticles (NPs) and deep eutectic solvent (DES) were synthesized, and the ceria-NP’s surfaces were modified by DES to form DES-ceria NP filler to develop mixed matrix membranes (MMMs). For the sake of interface engineering, MMMs of 2%, 4%, 6% and 8% filler loadings were fabricated using solution casting technique. The characterizations of SEM, FTIR and TGA of synthesized membranes were performed. SEM represented the surface and cross-sectional morphology of membranes, which indicated that the filler is uniformly dispersed in the polysulfone. FTIR was used to analyze the interaction between the filler and support, which showed there was no reaction between the polymer and DES-ceria NPs as all the peaks were consistent, and TGA provided the variation in the membrane materials with respect to temperature, which categorized all of the membranes as very stable and showed that the trend of stability increases with respect to DES-ceria NPs filler loading. For the evaluation of efficiency of the MMMs, the gas permeation was tested. The permeability of CO2 was improved in comparison with the pristine Polysulfone (PSF) membrane and enhanced selectivities of 35.43 (αCO2/CH4) and 39.3 (αCO2/N2) were found. Hence, the DES-ceria NP-based MMMs proved useful in mitigating CO2 from a gaseous mixture

Acute urinary retention as a result of a bladder diverticulum

An 11-month-old infant presented with acute urinary retention. He had presented 3 months earlier with complaints of an enlarging abdominal mass that was initially diagnosed as a mesenteric cyst on ultrasonography. Voiding cystourethrogram revealed a large bladder diverticulum. Bladder diverticulum should be a differential diagnosis in children, especially male, presenting with urinary retention, fever and an abdominal mass

Common Radiological Findings in Children with Suspected Foreign Body Inhalation

Background: Aspirated foreign bodies, an emergency situation, affecting children mostly in the first decade of life, either go undetected, are misdiagnosed or discovered unexpectedly. The purpose of this study was to determine the common radiological findings among children with suspected foreign body inhalation at Khyber Teaching Hospital, Peshawar Pakistan.Material and Methods: This cross-sectional descriptive study was conducted at the Department of ENT, Khyber Teaching Hospital, Peshawar, from April 2017 to October 2017. All patients (n=141) were subjected to detailed history and clinical examination. X ray chest (AP and lateral views) was performed to detect common radiological findings i.e., radiopaque foreign body (FB), pneumonia, emphysema, atelectasis and air trapping. The age and gender-stratified radiological findings were analyzed using Chi square test to see effect modifications, with P-value < .05 as statistically significant.Results: In this study, mean age was 8±3.563 years, with most of the children with suspected FB inhalation presenting in the 1-6 years age group (n=82; 58%). Sixty percent children were male while 40% were female, with emphysema (28%) and air trapping (25%) as the most common radiological findings. Radiopaque FB was detected in 16% of children on X-ray chest.Conclusions: Children with suspected foreign bodies should be thoroughly evaluated by both clinical and radiological examination

EFFECT OF LATERAL SEISMIC LOAD ON THE SIZE OF SHALLOW FOOTINGS

The aim of this paper is to study the effect of lateral and seismic loading on the width of shallow foundation. This is achieved by conducting an extensive parametric study over a range of governing parameters involving static and dynamic bearing capacity equations. The parameters include a range of cohesion and frictional angle values for cohesive and frictional soils respectively, and different peak horizontal ground acceleration values corresponding to different seismic zones of Pakistan. The bearing capacity equations used for analysis are Meyerhof's, and seismic bearing capacity equation o) Euro Code 8. Cohesion is varied from 50 kPa to 200 kPa, and frictional angle is varied from 25° to 45°. The results indicate significant effect of static lateral and seismic loading on the width of footing. It is therefore recommended that where significant earthquake hazards or lateral loads exist, they should be estimated and width of footing determined accordingly. If no lateral effect is considered, it is recommended to use a factor of safety of 7 for purely cohesive soils, and 10 for purely frictional soils

Effects of 6cm versus 2cm Resection Margin from Pylorus on Excess Weight Loss & Complication Rate for Laparo- Scopic Sleeve Gastrectomy: A Nine-Year Experience

Introduction: LSG is the gold standard sole bariatric procedure for morbid obesity. Small (2cm) and large (6cm) distance of resection margin from pylorus are both being used for neogastric sleeve formation however what is optimal distance remains controversial. Aims & Objectives: To assess excess weight loss results and complication rate with 6cm and 2cm distance of staple line from pylorus during a prolonged surveillance period. Place and Duration of Study: This retrospective cohort study was conducted at Fatima Memorial Hospital from Dec 2013 to Dec 2022 spanning 9 years. Material & Methods: Medical records of 50 morbidly obese patients aged 41- 50 yrs were segregated into two groups of 25 each based on the LSG procedure conducted. Group 1 had LSG with 6cm resection margin from pylorus while group 2 had a staple line distance of 2cm from pylorus for neogastric sleeve formation. The patients were subsequently followed up for excess weight loss (EXL) and BMI at 6 months, 1 year, 2 years, 3 years & 4-year interval. Data was entered and analyzed using SPSS version 21.P value ? 0.05 was considered significant. Results: EWL in Group 1 & 2 was 39.2± 6.77kg & 41.9± 4.35kg at 6 months,73.64± 6.49kg & 71.06± 7.77kg at 1 year, 65.52± 5.53kg & 63.92± 7.07kg at 2 years,58.16± 4.97kg & 57.28± 5.75kg at 3 years and 55.48± 3.39kg & 55.36± 3.72kg for 4 years were, not significant statistically. BMI in group 1 & 2 were 39.47± 5.11 & 35.88± 4.40 at 6 months, 29.22± 2.68 & 29.12± 2.00 at 1 year, 25.44± 1.96 & 24.73± 2.86 at 2 years, 22.84± 1.79 & 22.40±2.20 at 3 years and 21.66± 1.32, 21.67± 1.62 at 4 years were found to be statistically insignificant. Conclusion: With regards to extra weight loss, distance of resection margin from pylorus of 2cm or 6cm have identical effects but the latter has lowest complication incidence after 4 yrs of surveillance. Hence, a distance of 6cm is favoured to ensure safety of LSG for morbidly obese patients. And the findings of this study will help bariatric surgeons to improve technique of LSG in a safe and successful way for effective weight loss in morbidly obese patients

Hospital preparedness for disaster and mass casualty management in Pakistan: A cross-sectional evaluation study

Background: World Health Organization has advocated preemptive readiness of health systems to manage disastrous events. Pakistan is known to be highly susceptible to disasters on the one hand and significantly lacking in coping ability on the other. Preparedness of health facilities in such locales is especially important, despite which there is little published evidence regarding hospitals’ response capacity in Pakistan.Methods: From 12 most disaster prone districts of the country, a purposive sample of 20 hospitals was assessed using 51 indicators, scored as fully (2), partially (1), or not prepared (0). Two domains, disaster preparedness and mass casualty management, and five subdomains, networking, planning, staff-readiness, materials, and safety, were evaluated. Proportions of maximum possible scores achieved by an entity were categorized as acceptable (≥66 percent), partial (35-65 percent), or inadequate (<35 percent).Results: Out of the 20 hospitals, 14 (70 percent) were secondary and 3 tertiary level facilities (30 percent). Overall, hospitals were partially prepared with a score of 54.0 percent, 95 percent confidence interval [52.3 percent, 54.7 percent]. Disaster preparedness, 55.2 percent [54.0, 57.0], was significantly better prepared than mass casualty management, 49.2 percent [46.8, 51.6], p < 0.001. Overall, facility safety was the least prepared among the subdomains, 38.3 percent [31.8, 44.8], while materials were the best, 75.9 percent [72.6, 79.3]. The least prepared subdomains were staff-readiness in Punjab, 52.1 percent [47.5, 56.8], and facility safety in KP, 29.2 percent [22.1, 36.4].Conclusions: Hospitals’ preparedness for disaster and mass casualty management is deficient in these most vulnerable districts of Pakistan. Improvement initiatives commensurate with locale vulnerabilities should be instituted