Pre-exponential Factor Research Articles

Stroboscopic sampling moiré microscope (SSMM) for investigating full field in-plane vibration of MEMS mechanical transducers

Precise analysis of the full-field in-plane vibration of microelectromechanical system (MEMS) transducers is crucial for assessing their device functionality and performance. As an example, in the context of frequency/amplitude modulation of Quartz Tuning Fork (QTF)-based atomic force microscopy (AFM) systems, understanding QTF’s in-plane vibration can significantly enhance accurate evaluation of tip-sample forces. Current methods, such as analytical and numerical approaches, have limitations when it comes to providing accurate measurements. To address these limitations, we proposed an experimental approach that combines stroboscopic and sampling moiré (SM) techniques. This method focuses on investigating the in-plane vibration of a QTF and utilizes the obtained results to measure the sensor’s dynamic properties such as vibration mode shape, resonance frequency (f0), and quality factor (Q). Nanometer-scale light pulses, generated using a custom-designed stroboscope, are synchronized with the QTF’s excitation voltage to freeze the vibration effectively, enabling imaging using a standard CCD camera. Subsequently, SM analysis is employed to extract the surface vibration profile, facilitating the measurement of vibration mode shape, f0, and Q. This technique shows promise for analyzing the dynamic behavior of various micro-devices compatible with the sample preparation process.

Chorioamnionitis and Earlier Gestational Age Are Associated with Neonatal Hypercalcemia After Maternal Magnesium Sulfate Therapy: A Case-Control Study

BackgroundMagnesium sulfate (MgSO4) is a tocolytic agent used to treat gestational hypertension and to prevent preterm labor. Neonatal hypocalcemia is a well-known side effect of maternal MgSO4 use. Cases of neonatal hypercalcemia after maternal MgSO4 have been reported. Little is known about neonatal hypercalcemia following maternal MgSO4 therapy. We investigated the frequency and risk factors of neonatal hypercalcemia in this setting. MethodsThis case-control study investigated serum calcium in neonates born within 24 h after maternal MgSO4 administration. We reviewed the electronic medical records of Saitama City Hospital for pregnant women who were treated with MgSO4 between January 2016 and December 2021. There were 504 pregnant women that were treated with MgSO4. We enrolled 257 neonates. Hypercalcemia was defined as serum albumin-corrected calcium greater than 2.74 mmol/L (11 mg/dL). We collected the perinatal information from the mothers and neonates. ResultsTwenty-one neonates (8%) had hypercalcemia at birth (H group). Umbilical arterial ionized calcium, neonatal plasma ionized calcium, and total serum calcium were significantly higher in H group than in N group. Neonatal serum albumin, on the other hand, was lower in H group than in N group. Neonates in H group were born earlier (28.4 ± 3.1 vs. 32.4 ± 3.1 wk, p <0.001) and more likely to be born to mothers with pathological chorioamnionitis (91.0% vs. 12.7%, p <0.001) than neonates who were normocalcemic (N group). Serum alkaline phosphatase was lower in hypercalcemia group (661 ± 276 vs. 816 ± 265 U/L, p = 0.01). Multivariate analysis showed that earlier gestational age and chorioamnionitis were significant risk factors. ConclusionHypercalcemia after maternal MgSO4 was seen in 8% of neonates. Maternal chorioamnionitis and earlier gestational age were associated with this condition.

Robust Collaborative Visual-Inertial SLAM for Mobile Augmented Reality.

Achieving precise real-time localization and ensuring robustness are critical challenges in multi-user mobile AR applications. Leveraging collaborative information to augment tracking accuracy on lightweight devices and fortify overall system robustness emerges as a crucial necessity. In this paper, we propose a robust centralized collaborative rnulti-agent VI-SLAM system for mobile AR interaction and server-side efficient consistent mapping. The system deploys a lightweight VIO frontend on mobile devices for real-time tracking, and a backend running on a remote server to update multiple submaps. When overlapping areas between submaps across agents are detected, the system performs submap fusion to establish a globally consistent map. Additionally, we propose a map registration and fusion strategy based on covisibility areas for online registration and fusion in multi-agent scenarios. To improve the tracking accuracy of the frontend on agent, we introduce a strategy for updating the global map to the local map at a moderate frequency between the camera-rate pose estimation of the frontend VIO and the low-frequency global map optimization, using a tightly coupled strategy to achieve consistency of the multi-agent frontend poses estimation in the global map. The effectiveness of the proposed method is further confirmed by executing backend mapping on the server and deploying VIO frontends on multiple mobile devices for AR demostration. Additionally, we discuss the scalability of the proposed system by analyzing network traffic, synchronization frequency, and other factors at both the agent and server ends.

Analysis of painful situations during unsedated esophagogastroduodenoscopy.

Background and study aims Although esophagogastroduodenoscopy (EGD) is a widely used technique, the procedure is often associated with discomfort. This study aimed to analyze painful situations, their frequency, and factors associated with patient discomfort during EGD. Patients and methods This prospective observational study included patients scheduled to undergo EGD. Seven endoscopists recruited patients scheduled for EGD screening or surveillance. Each endoscopist enrolled 20 patients, performing 10 EGD procedures using ultraslim endoscopes and 10 with standard-sized endoscopes. Data regarding painful situations and frequency were collected using specialized buttons pressed by the patients during EGD. A survey about overall discomfort was conducted after the procedure. Results We analyzed data from 140 patients. Esophageal insertion and duodenal observation were associated with the highest incidence of pressing the pain button, accounting for 59.3% and 40.7% of the cases, respectively. The factor associated with pressing the pain button during esophageal insertion was endoscopist experience (< 10 years). In contrast, younger age and female sex were the factors associated with pressing the pain button during duodenal observation. In the post-procedure survey, 63.6% of patients reported discomfort. Factors associated with patient discomfort included pressing the pain button during esophageal insertion (odds ratio [OR]: 2.84, P = 0.01) and previous painful EGD experience (OR: 2.41, P = 0.03). Concusions This study provides objective data on painful situations, their frequency, and related factors during EGD. Further research and interventions focusing on pain reduction during endoscopic procedures are warranted. The results of this study will help endoscopists manage painful situations and potentially improve skills.

Measuring the Quality of Life and Psychological Distress of Dormitory Students at a University in Sharjah.

Living in university dormitories can have a negative impact on students' psychological health and quality of life. This cross-sectional study aimed to investigate the frequency and risk factors of psychological distress and quality of life among university students living in dormitories at a university in Sharjah. A total of 336 participants between the ages of 18 and 24 years were recruited. The World Health Organization Quality of Life Brief Version (WHOQOL-BREF) scale and Kessler's Psychological Distress Scale (K10) were used to assess the quality of life (QoL) and psychological distress (PD), respectively. Data were analyzed via SPSS 25 (Chicago, IL: IBM Corp.) and p≤5% were reported as statistically significant. A total of 43.45% (n=145) of participants lived in dormitories, while 56.55% (n=186) lived elsewhere. The mean QoL was higher (94.55) for non-dormitory students compared to dormitory students (88.97) (p<0.000, 95% CI= -8.591 to -2.577). Our results also show that the QoL is inversely proportional to PD(p<0.001). The findings of this study indicate that students living in dormitories are at higher risk of experiencing lower QoL compared to those living elsewhere, on top of the high rates of PD that they have to endure.

Large eddy simulation of soot formation in a turbulent lifted flame with a discretized population balance and a reduced kinetic mechanism

This article presents simulations of a turbulent lifted flame using the large eddy simulation-transport probability density function-discretized population balance equation approach. This approach takes into account the interaction between turbulent reacting flow and soot particle formation. A reduced chemical kinetics mechanism including a series of polycyclic aromatic hydrocarbons (PAHs) species linked to soot formation is generated employing the approach of the directed relation graph error propagation and is tested on a perfectly stirred reactor under varying equivalent ratio conditions and premixed flames. The soot kinetics model includes the PAH-based nucleation and surface condensation, the hydrogen abstraction acetylene addition surface growth and oxidation mechanism, and the size-dependent aggregation. The soot morphology considers the surface area and other geometrical properties for both spherical primary particles and fractal aggregates. The simulation results show, in general, reasonably good agreement with experimental measurements in terms of lifted height, flame shape, flow-field velocity, the hydroxyl radical, and soot volume fraction. A discussion of micromixing and its modeling in the context of the Interaction by Exchange with the Mean model is also presented. To investigate the effect of the soot micromixing frequency factor on soot particles, an additional simulation is conducted where this factor is reduced by a factor of 10 for the soot particles. The maximum soot volume fraction is observed to increase slightly. However, compared with the impact of kinetics on soot modeling, this effect is a minor one.

Frequency and Risk Factors Associated with Retinopathy of Prematurity: A Single Centre Study

Retinopathy of prematurity is the irregular development of blood vessels in the growing retina of premature infants, which can primarily lead to blindness. Objective: To identify frequency and risk factors associated with retinopathy of prematurity. Methods: A cross-sectional study was conducted on 140 premature infants (gestational age ≤34 weeks) investigated in the Neonatal Intensive Care Unit of Central Park Teaching Hospital, Lahore. Preterm neonates’ weight ≤1.8 Kg and gestational age ≤34 weeks were enrolled. The neonate’s demographic details, risk factors for retinopathy, eye examinations, and follow-up were recorded. Their maternal history included maternal age, gestational age, and maternal risk factors. During their hospital stay, clinical progress, morbidity, and mortality were assessed and monitored. Descriptive statistics were done using SPSS version 26.0. Results: From these 140 premature infants, 74 (52.9%) were male and 66 (47.1%) were female. The average gestational age was 30.4 ± 2.36 weeks, with a mean birth weight of 1.3 ± 0.28 kg. Of total premature infants, 14 (10%) developed Retinopathy of premature whereas 6 (4.3%) infants expired and 21 (15%) lost to follow-up. Grade-I and Grade-II retinopathy of prematurity were developed in 8 (57.1%) and 6 (42.9%), respectively and based on regression analysis, low gestational age, respiratory distress syndrome, and sepsis independently predicted the onset of prematurity. Conclusions: It was concluded that the prevalence of retinopathy of prematurity was 10%. Lower gestational age, blood transfusion, lower birth weight, anemia, bronchopulmonary dysplasia, sepsis, and O2 therapy were primary factors of risk in retinopathy of prematurity development.

Studies of Kinetics and Non-Isothermal Decomposition of Synthesized Novel Organic Terpolymer Resin

Abstract: The terpolymer resin 2,4-DHP-4-PAF-III was prepared by condensation of 2,4-dihydroxypropiophenone, 4- pyridylamine and formaldehyde in the presence of 2M hydrochloric acid as a catalyst in the temperature range 125 ± 2 0C for 5 hrs in 3:1:5 molar ratios of reactants. Elemental analysis, FT-IR, and 1H-NMR spectral studies have been carried out to confirm the structure of the resin. The thermal degradation behavior of terpolymer was studied using thermogravimetric analysis (TGA) in air atmosphere at a heating rate of 10 0C/min. Sharp-Wentworth and Freeman-Carroll methods were used to calculate thermal activation energy (Ea), entropy change (∆S), free energy change (∆F), apparent entropy change (S*), frequency factor (Z) and order of reaction (n). Thermal activation energy (Ea) calculated by Sharp-Wentworth (28.81 KJ/mole) method and Freeman-Carroll (29.47 KJ/mole) method are in good agreement.

A microsystem for in vivo wireless monitoring of plastic biliary stents using magnetoelastic sensors.

With an interest in monitoring the patency of stents that are used to treat strictures in the bile duct, this paper reports the investigation of a wireless sensing system to interrogate a microsensor integrated into the stent. The microsensor is comprised of a 28-μm-thick magnetoelastic foil with 8.25-mm length and 1-mm width. Magnetic biasing is provided by permanent magnets attached to the foil. These elements are incorporated into a customized 3D polymeric package. The system electromagnetically excites the magnetoelastic resonant sensor and measures the resulting signal. Through shifts in resonant frequency and quality factor, the sensor is intended to provide an early indication of sludge accumulation in the stent. This work focuses on challenges associated with sensor miniaturization and placement, wireless range, drive signal feedthrough, and clinical use. A swine specimen in vivo experiment is described. Following endoscopic implantation of the sensor enabled plastic stent into the bile duct, at a range of approximately 17 cm, the signal-to-noise ratio of ~106 was observed with an interrogation time of 336 s. These are the first reported signals from a passive wireless magnetoelastic sensor implanted in a live animal.

베이커리카페에 대한 경험가치가 브랜드연상과 충성도에 미치는 영향

Objective : The purpose of this study is to provide a theoretical basis for improving management performance in the future by providing useful data for securing loyal customers for sustainable management and providing basic data for establishing differentiated marketing strategies. Methods : This study conducted an online survey in August 2024 to collect data, adopted a total of 301 questionnaires, and analyzed them as effective samples Then, this study used SPSS Statistics 23.0 to conduct frequency analysis, factor analysis, trust analysis, and multiple regression analysis. Results : According to hypothesis test results, it was found that the experience value had a positive and significant influence on brand association and loyalty. In addition, brand association had a positive and significant influence on loyalty. Implications : The brand association and experience value for bakery cafes significantly affected the attitude and behaviorial loyalty, and it suggests that building a strong brand association is important to secure loyal customers for sustainable management and provide various experience values to customers.

The Impact of ESG Facilitation Factors Perceived by Franchise Hair Salon Workers on Adoption Intentions

The purpose of this study is to analyze the differences in ESG promotion factors and adoption intentions among franchise hair salon employees based on their general characteristics, and to identify the impact of ESG promotion factors on adoption intentions. This study aims to provide the necessary foundational data for establishing effective policies and implementation strategies. A survey was conducted among franchise hair salon employees from Generation Z to older generations, resulting in 492 valid responses used for the final analysis. The data were analyzed using SPSS 22.0, employing frequency analysis, factor analysis, reliability analysis, and multiple regression analysis. The study results revealed differences in ESG promotion factors based on generation, education level, position, and work experience. Adoption intentions varied by generation, education level, and position. ESG promotion factors, including management willingness, government policy, and consumer demand, significantly influenced adoption intentions, with management willingness being the most crucial factor. This study provides essential insights for establishing ESG adoption and implementation strategies in the franchise hair salon industry and contributes to understanding generational differences in ESG perceptions. Future research should focus on collecting more diverse data and conducting detailed studies on the characteristics and perceptions of franchise hair salon managers.

The Hidden Mechanism: Excited-State Proton-Electron Pair Transfer in Metal Nanocluster Emission.

Comprehending the underlying factors that govern photoluminescence (PL) in metal nanoclusters (NCs) under physiological conditions remains a highly intriguing and unresolved challenge, particularly for their biomedical applications. In this study, we evaluate the critical role of excited-state proton-coupled electron transfer in the emission of metal NCs. Our findings demonstrate that hydronium ion (H3O+) binding can trigger a nonlinear, pH-dependent excited-state concerted electron proton transfer (CEPT) reaction. This involves simultaneous electron transfer from the Au(0) core to the Au(I)-ATT (ATT denotes 6-aza-2-thiothymidine) surface and proton transfer from H3O+ to the ATT ligand in a single step, greatly promoting vibrations and rotations of the Au(I)-ATT surface, resulting in substantial PL quenching of Au10(ATT)6 NCs. Further analyses show that the unique CEPT dynamics are strongly influenced by the opposing effects of increased reorganization energy and a larger pre-exponential factor on the electron transfer rate. Moreover, the proposed excited-state CEPT process is found to be prevalent in core-shell relaxation metal NCs, such as Au25(SR)18 (SR denotes thiolate) NCs, and serves as an important factor in limiting their PL emission. By simply controlling the pKa of the ligands, the emission performance of Au25(SR)18 can be easily regulated in physiological environments.

The effectiveness and factors influencing frequency of endoscopic bougie dilatation in treating postoperative anastomotic stenosis of congenital esophageal atresia.

This study is to evaluate the effectiveness and frequency factors of endoscopic bougie dilatation in treating postoperative anastomotic stenosis of congenital esophageal atresia (CEA). The clinical data of patients of anastomotic stenosis with endoscopic bougie were retrospectively analyzed. According to the number of dilation times (ND), patients were divided into two groups (Group 0: ND < 3; Grooup1: ND ≥ 3), and the differences in multiple clinical data were compared. Lasso regression and Ridge regression were used to screen important variables. Classification models were built utilizing various machine learning algorithms and their performance were evaluated. Finally, Kaplan-Meier model was used to estimate the probable-time distribution of children achieving normal feeding. Seventy-five patients underwent a total of 210 times of dilation, with a median of 3 times of dilation. The overall effectiveness was 98.67% (74/75), with perforation in 2 case (0.95%), and obvious bleeding in 3 cases (1.43%). Initial diameter of bougie, final diameter of bougie, treatment pattern (Regular: dilation each 4weeks; Wait-and-see: dilation until symptoms present), age at final dilation, esophageal obstruction by food were the factors related to ND. Random Forest (RF) and Logistic regression (LR) model were excellent models for predicting ND. The median age for achieving normal eating in Group0 was 120 days (95% CI: 90-160), while it was 270 days (95% CI: 240-460) in Group1 with a statistically significant difference (P < 0.0001). Endoscopic bougie dilatation is a safe and effective treatment for anastomotic stenosis. Selecting the appropriate bougie, using symptoms as the criterion for dilation, and minimizing the dilations under 3 times constitute a rational strategy.

Thermal engineering and chemical kinetics of wood pellets torrefication

Relevance. The widespread distribution and availability of biomass in the regions of Russian Federation make it possible to consider it as a renewable energy source with a lower negative impact on the environment compared to fossil fuels, since biomass is recognized as a carbon-neutral fuel. The use of biomass as a fuel in the form of pellets is increasing, which provides increased density and heat value. At the same time, pellets as a fuel or as a technological raw material have a significant disadvantage – low hydrophobicity. This problem is solved by torrefaction – low-temperature pyrolysis at a temperature of 200–300°C to produce bio-carbon. The study of the wood pellets torrefaction in order to improve it is an urgent task. Aim. To identify the impact of the parameters of the torrefaction of wood pellets on the thermal characteristics of the product (the highest heat value of bio-coal) and the regime parameters of the process (mass and energy yields), as well as to determine the parameters of the chemical kinetics of low-temperature pyrolysis as the basis for mathematical modeling and development of efficient torrefaction reactors. Object. Torrefied coniferous wood pellets of domestic production (Moscow region). Methods. Experimental study of the low-temperature pyrolysis thermal characteristics; synchronous thermal analysis in an inert atmosphere. Results. It was found that during the torrefaction of wood pellets in an inert atmosphere, a change in the holding time in the range of 30–60 minutes does not significantly affect the higher heat value, mass and energy yield of bio-coal, while an increase in temperature from 250 to 300°C reduces mass and energy yield, and the higher heat value increases by 26%. The dynamics of mass loss and thermal effects when heated to 600°C at a rate of 10 K/min are determined by means of the synchronous thermal analysis. It is established that the chemical kinetics of the process is described by a generalized reaction of the order n=1.507, in the Arrhenius equation the activation energy E=71.25 kJ/mol, the pre-exponential factor A=4772 s–1.

Advancements in renewable energy: Achieving milder reaction conditions in biodiesel synthesis from green seed canola oil with pristine ZIF-8

This study explores the enhancement of reaction conditions for biodiesel production from green seed canola oil through the methanolysis reaction using pristine ZIF-8 as a catalyst. The research focused on the effects of varying the methanol-to-oil molar ratio, temperature, and reaction time as well as their combined effects on biodiesel yield. To analyze these factors, Response Surface Methodology (RSM) paired with Central Composite Design (CCD) was employed. The quadratic model was identified as the best fit for the experimental data, evidenced by a high determination coefficient (R²) of 0.99, with all model parameters proving significant. A comprehensive characterization of the catalyst was conducted using various techniques. The surface and pore properties were examined using N2 adsorption-desorption measurements. X-ray diffractometry (XRD) was employed for structural analysis, while X-ray photoelectron spectroscopy (XPS) presented the binding information of the sample. Fourier transform infrared spectroscopy (FT-IR) provided insights into the functional groups present. Thermal gravimetric analysis (TGA) assessed the thermal stability of the catalyst. Results revealed that ZIF-8 significantly improved biodiesel production, with optimal conditions identified at a reaction temperature of 160 °C, a duration of 2.5 h, and methanol to oil (M/O) molar ratio of 26, resulting in a biodiesel yield of 85 %. This yield is close to the predicted value, demonstrating the reliability of the developed model. The kinetic analysis was performed under optimal reaction conditions. From this, the activation energy (Ea) and the pre-exponential factor (A) were obtained to be 14.5 kJ/mol and 3.4×10−7 min−1, respectively. The use of pristine ZIF-8 in biodiesel production from a low-quality and cheap oil offers a more efficient and milder reaction conditions, with potential for significant reductions in production costs and environmental impact.

Syntheses, Structures, and Thermal Decomposition Kinetics of Two Silver/Copper‐Based Coordination Compounds with 1,2,4‐Triazole‐Containing Ligand

AbstractIn this work, two silver/copper‐based coordination compounds {[Ag(tty)]⋅NO3}n (1) and {[Cu2Cl2(tty)2(H2O)2]⋅Cl⋅NO3 ⋅ (H2O)2}n (2) (tty=1,2,4,5‐tetra(1H‐1,2,4‐triazol‐1‐yl))benzen), were synthesized using the different metal salts under the hydrothermal condition. Structural analyses show that compound 1 features tilted L‐shaped 1D Ag chains structure and compound 2 presents a 2D layer with free Cl−, NO3− and water molecules. The experimental results reveal that 1 displays considerably high thermal stability with the thermal decomposition temperature above 337 °C compared to compound 2, which further exemplifies that the framework structures may have a crucial effect on the resultant thermal stability. Additionally, the non‐isothermal kinetics parameters were evaluated at different heating rates by Kissinger's and Ozawa‐Doyle's methods. Importantly, the kinetic triplets (the apparent activation energy (Ea), the preexponential factor (logA) and the mechanism function (ƒ(α)) and the related thermodynamic parameters (the Gibbs energy of activation, ▵G≠, the enthalpy of activation, ▵H≠, and the entropy of activation, ▵S≠) of the thermal decomposition processes are discussed and calculated in detail.

A geometrically scalable method for manufacturing high quality factor mechanical resonators.

We present what we believe to be a novel, geometrically scalable manufacturing method for creating compact, low-resonance frequency, and high quality factor fused silica resonators. These resonators are intended to be used in inertial sensors for measuring external disturbances of sensitive physics experiments. The novel method uses direct bonding and chemical-mechanical polishing (CMP) in order to overcome the limitations of current subtractive manufacturing methods, which face prohibitive cost and complexity as material removal increases, inherently restricting the design flexibility of the resonator. We demonstrate a prototype with a test mass of only 3 g that reaches a quality factor of Q = 118 000 ± 400 at a resonance frequency of below 20 Hz. This advancement is particularly significant for future gravitational wave observatories, such as the Einstein Telescope.

Design and analysis of flexible antenna sensor for non-invasive detection of pregnancy in bovine

This research article presents a monopole antenna-based sensor for detecting cow pregnancy through urine analysis. The proposed flexible antenna sensor is printed on denim fabric with a permittivity of 1.7 and a loss tangent of 0.002. The flexible antenna resonates at 2.4 GHz and the gain of the proposed antenna sensor is 2.016 dBi, with a corresponding efficiency of 96.8%. The antenna's dimensions are 30 × 44 × 1 mm3. The substrate region behind the inner area of the radiator ring acts as a sensing area. This substrate can absorb liquids through the sensing area, causing the dielectric properties of the substrate to change according to the dielectric constant of the fluid under test. Urea concentration in pregnant cow urine is 11.06 mg/dL and 1.39 mg/dL in non-pregnant cow urine. The proposed antenna sensor uses microwave signals to detect pregnancy in cows. The deviation in resonance frequency and quality factor are used as key parameters for detecting cow pregnancy.

Prevalence and Risk Factors of Surgical Site Infection Following Cesarean Section

Background: Surgical site infection (SSI) following Cesarean section (C-section) is a common cause of morbidity and imposes a significant load on the healthcare system. Therefore, the prevalence of factors that make individuals more susceptible to SSI after a C-section should be accurately assessed. Objectives: This study aimed to determine the frequency and risk factors for infection following C-section in women referred to the maternity ward of Ali ibn Abi Talib Hospital in Zahedan, Iran, from 2020 to 2022. Methods: This descriptive cross-sectional study was performed on all women admitted to the maternity ward of Ali ibn Abi Talib Hospital in Zahedan, whether undergoing elective or emergency C-sections. The patients were entered into the study with informed consent and were followed up to one month after surgery. Results: This study showed that approximately 5300 cases of C-sections were performed in Ali ibn Abi Talib Hospital during the mentioned period, of which 120 patients were referred to this hospital again because of surgical site infections. The occurrence of SSI in the present study was 2.26%, and obesity and anemia were identified as the predominant risk factors. The findings showed that the incidence of patients with SSI following a C-section with obesity, anemia, skin scar of previous C-section, rupture of membranes before C-section (&gt; 6 hours), and diabetes mellitus were 80, 76.8, 36.7, 33.3, and 24.2 %, respectively. Conclusions: The recorded incidence of SSI following C-section was comparatively lower than findings from prior studies conducted in developing countries. Although the frequency of these complications is desirable, there are the same number of irreparable complications to mothers and infants and high costs for families and society.

Semiclassical Scattering by Edge Imperfections in Topological Insulators in a Magnetic Field

We study the scattering of edge states of 2D topological insulator in the uniform external magnetic field due to edge imperfections, common in realistic 2D topological insulator samples. The external magnetic field breaks time-reversal symmetry, opening the possibility of the scattering of otherwise topologically protected fermionic edge states. The scattering happens to be always an over-barrier event, irrespective of the shape of the edge deformation and magnitude of the magnetic field. We use the advanced Pokrovsky–Khalatnikov semiclassical approach, which allows us to obtain analytically both the main exponential and pre-exponential factors of the scattering amplitude for wide classes of analytic deformation profiles.