Envelope Technique Research Articles

The impact of closed suction wound drainage on chronic pain and health-related quality of life after posterior spinal fusion in patients with adolescent idiopathic scoliosis.

Closed suction subfascial drainage is widely used after instrumented posterior spinal fusion in patients with a spinal deformity. The aim of this study was to determine the effect of this wound drainage on the outcomes in patients with adolescent idiopathic scoliosis (AIS). This was a further analysis of a randomized, multicentre clinical trial reporting on patients after posterior spinal fusion using segmental pedicle screw instrumentation. In this study the incidence of deep surgical site infection (SSI) and chronic postoperative pain at two years' follow-up are reported. We conducted a randomized, multicentre clinical trial on adolescents undergoing posterior spinal fusion for AIS using segmental pedicle screw instrumentation. A total of 90 consecutive patients were randomized into a 'drain' or 'no drain' group at the time of wound closure, using the sealed envelope technique (1:1). The primary outcomes in the initial study were the change in the level of haemoglobin in the blood postoperatively and total blood loss. A secondary outcome was the opioid consumption immediately after surgery. The aim of this further study was to report the rate of deep SSI and persistent postoperative pain, at two years' follow-up. As previously reported, the mean 48-hour opioid consumption was significantly higher in the no drain group (2.0 mg/kg (SD 0.8) vs 1.4 mg/kg (SD 0.7); p = 0.005). There were no delayed deep SSIs. At two years' follow-up, the mean Scoliosis Research Society 24-item questionnaire (SRS-24) total score did not differ between the groups (4.11 (SD 0.47) vs 4.16 (SD 0.33); p = 0.910). The mean SRS-24 pain score was 4.28 (SD 0.48) in the no drain group compared with 4.33 (SD 0.66) in the drain group (p = 0.245). Seven patients (19%) in the no drain group and six in the drain group (14%) reported moderate to severe pain (numerical rating scale ≥ 4) at two years' follow-up (p = 0.484). The general self-image domain score was significantly higher in the no drain group compared with the drain group (4.02 (SD 0.74) vs 4.59 (SD 0.54); p < 0.001). The main finding in this study was that more severe pain immediately after surgery did not result in a higher incidence of chronic pain in the no drain group compared with the drain group. Back pain and health-related quality of life at two years' follow-up did not differ between the groups. The patient-reported self-image domain was significantly better in the no drain group compared with the drain group.

Scaled envelope models for multivariate time series

Vector autoregressive (VAR) models have become a popular choice for modeling multivariate time series data due to their simplicity and ease of use. Efficient estimation of VAR coefficients is an important problem. The envelope technique for VAR models is demonstrated to have the potential to yield significant gains in efficiency and accuracy by incorporating linear combinations of the response vector that are essentially immaterial to the estimation of the VAR coefficients. However, inferences based on envelope VAR (EVAR) models are not invariant or equivariant upon the rescaling of the VAR responses, limiting their application to time series data that are measured in the same or similar units. In scenarios where VAR responses are measured on different scales, the efficiency improvements promised by envelopes are not always guaranteed. To address this limitation, we introduce the scaled envelope VAR (SEVAR) model, which preserves the efficiency-boosting capabilities of standard envelope techniques while remaining invariant to scale changes. The asymptotic characteristics of the proposed estimators are established based on different error assumptions. Simulation studies and real-data analysis are conducted to demonstrate the efficiency and effectiveness of the proposed model. The numerical results corroborate our theoretical findings.

Effects of board games on balance in association with cognition in community-dwelling older adults

Objectives: Falls among the elderly are a prevalent concern. Maintaining balance and preventing falls necessitate cognitive processes, such as information processing speed and executive functions. The objective was to determine the impacts of board games on cognition, balance, and risk of falls among community-dwelling elders. Methods: Sixty-four elders aged 65 years and above, with mini–mental state examination (MMSE), scores above 26 and Berg balance scale (BBS) scores between 41 and 52, were recruited with a sample size of 64 divided into two groups, 32 in each group. Participants were randomized through the sealed envelope technique into experimental (engaging in board games) and control groups (not involved in board game activity). The BBS, MMSE, timed upand-go test (TUGT), and dynamic gait index (DGI) were assessed at baseline, four weeks, and eight weeks. Results: Participants engaging in board games (mean age 69.93 ± 4.77) demonstrated significant improvements in cognition, with MMSE scores increasing from 26.8 ± 0.83 at baseline to 28.6 ± 0.74 after eight weeks (P &lt; 0.001). BBS scores enhanced from 47.2 ± 1.84 to 49.8 ± 5.15 (P &lt; 0.001), DGI scores improved from 19.65 ± 1.49 to 21.37 ± 1.47 (P &lt; 0.001), and TUGT scores decreased from 10.40 ± 0.69 to 10.22 ± 0.67 (P &lt; 0.001). Mixed analysis of variance revealed significant differences between experimental and control groups for MMSE (P &lt; 0.001), BBS (P &lt; 0.001), DGI (P &lt; 0.001), and TUGT (P &lt; 0.001). Conclusion: The eight-week interactive physical-cognitive training program involving board games was found to enhance cognitive performance, mobility, and balance and decrease fall risk among the elderly.

Modified Roll Envelope Technique Combined With Apically Repositioned Flap (MRARF) for Peri-Implant Soft Tissue Augmentation-A Case Series.

In the present case series, we performed implant surgery using a modified roll envelope technique and an apically repositioned flap (MRARF). To improve patients' peri-implant soft tissue phenotypes, they underwent dental implantation following the buccal contour concavities, inadequate keratinized tissue width, and soft tissue thickness simultaneously. This case series includes 4 patients treated between July 2021 and February 2022 who received dental implants and guided bone regeneration treatment 6 months earlier and were to be taken up for second-stage surgery. They were eligible for the MRARF technique if each implant site showed a labial and buccal deficiency and a reduced keratinized mucosa width than the adjacent teeth. Sutures were removed 2 weeks after surgery, and a provisional restoration was delivered. A final impression was taken at 6 weeks to produce the definitive implant-supported restoration. All surgery sites healed uneventfully, and no postoperative pain or excessive swelling was reported. The modified flap design allowed for increasing the width and thickness of keratinized mucosa with a minimally invasive technique. A harmonious color, texture, and mucogingival junction position that matched the surrounding tissue and adjacent teeth was achieved, and all patients were satisfied with the final results. MRARF at second-stage implant surgery could obtain satisfactory results regarding vertical and horizontal aesthetic gingival contours and an adequate width and thickness of keratinized mucosa around the implants.

Approximations and inference for envelopment estimators of production frontiers

Nonparametric methods have been commonly used to assess the performance of both private and public organizations. Among them, the most popular ones are envelopment estimators such as Free Disposal Hull (FDH) or Data Envelopment Analysis (DEA), which estimate the attainable sets and their efficient boundaries by enveloping the cloud of observed units in the appropriate input-output space. However, these nonparametric envelopment techniques do not provide estimates of marginal products and other coefficients of economic interest. This paper presents a new approach that provides local estimates of all the desired partial derivatives and economic coefficients, which complement and complete the analysis based on nonparametric envelopment estimators. We improve nonparametric estimators by estimating nonparametrically smoothed efficient boundaries and providing derivatives and other coefficients without having to assume any parametric structure for the frontier and the inefficiency distribution. Our approach offers several advantages, such as a flexible nonparametric adjustment of the efficient frontier based on local linear models; a general multivariate efficiency model based on directional distances where one can choose the desired benchmark direction; the possibility of assessing the impact of external-environmental variables; a bootstrap-based statistical inference for deriving confidence intervals on the estimated coefficients for nonparametric and robust frontier approximations; the possibility of including factors aggregating inputs or outputs and recovering the estimated coefficients in the original units. To demonstrate the usefulness of the proposed approach, we provide an illustration in the field of education, where economic coefficients are important but the parametric assumptions have been questioned.

Superior versus anterior plating of midshaft clavicle fractures: 6 months follow up (union rates, risks, and complications: hardware irritation and need for removal)

Background Operative management of midshaft clavicle fractures is gaining popularity. The clavicle is a tubular bone with a flat lateral end. Open reduction and internal fixation could be achieved by the application of plates and screws either to the superior or anterior surface of the clavicle. However, there is no consensus in the literature to support one technique over the other. This study aims to compare the early functional and radiographic outcomes of anterior versus superior plating for the treatment of midshaft clavicle fractures. Patients and methods From March 2021 to November 2022, a prospective randomized clinical trial was conducted at our institute. We included all patients with isolated midshaft clavicle fractures. Thirty-six patients were randomized by the closed envelope technique, 18 were managed with superior plating (superior group), and the other 18 patients were managed using anterior plating (anterior group). All patients were followed up for 6 months. All patients were assessed clinically for union, range of motion, and functional scores. The secondary outcome measures included operative time, complications, hardware irritation, and the need for hardware removal or secondary procedure. Results The mean time to full union was 11.28 weeks in the anterior group and 11.72 weeks in the superior group. Mean constant shoulder score for the anterior group was 84.11 while for the superior group it was 82.67. No patients had skin and wound complications in the anterior group versus one patient in the superior group that got superficial infection successfully managed by repeated dressing and antibiotics. There was no statistically significant difference between superior and anterior plating regarding union, functional scores, return to ADLs, hardware problems, or complications. Conclusion Both superior and anterior plating of the clavicle fractures are safe treatment options for displaced midshaft clavicle fractures, and they lead to similar functional outcomes, functional scores, and complication rates. Moreover, the selection of the technique of plating depends on surgeon preferences.

A Comparative Study of Intrathecal 0.5% Hyperbaric Bupivacaine and Intrathecal 0.75% Hyperbaric Ropivacaine in Elective Lower Segment Cesarean Section

Aim: To evaluate and compare the efficacy and safety of intrathecal 0.5% hyperbaric bupivacaine and intrathecal 0.75% hyperbaric ropivacaine in patients posted for elective lower segment cesarean section (LSCS) under spinal anesthesia. Objective: The objective of this study was to compare intrathecal 0.5% hyperbaric bupivacaine and intrathecal 0.75% hyperbaric ropivacaine in patients posted for elective LSCS under spinal anesthesia with respect to the onset and duration of sensory block, onset and duration of motor block, hemodynamic parameters, and adverse effects. Material and Methods: Patients with ASA physical status II of age ranging from 18 to 35 years were included in the study. Patients were randomized into two groups using a sealed envelope technique. A) Group B (n = 30); 10 mg 0.5% (2 mL) bupivacaine + Inj. buprenorphine (60 µg). B) Group R (n = 30); 15 mg 0.75% (2 mL) ropivacaine + Inj. buprenorphine (60 µg). Hemodynamic parameters, onset and duration of sensory, and motor blockade, level achieved, and side effects were compared between the two groups. Qualitative data were analyzed by Chi-square test and quantitative data were analyzed by independent sample t-test. Results: None of the patients in either group dropped out of the study. At the beginning of the study, patients’ demographic characteristics, hemodynamic parameters, time of onset of sensory and motor blockade, postoperative pain relief, and side effect profile were comparable between the two groups. However, 0.75% hyperbaric ropivacaine can serve as an efficacious alternative to the conventional 0.5% hyperbaric bupivacaine for patients undergoing elective cesarean section, as it produces a similar quality of block with faster attainment of desired sensory levels and early recovery from the motor blockade, thereby allowing early ambulation. Conclusion: Considering its comparable duration of sensory blockade, stable hemodynamics, and postoperative analgesia, along with a shorter duration of motor blockade, the use of 0.75% hyperbaric ropivacaine can be considered a safe and effective alternative to bupivacaine in elective LSCS.

Cross-correlation technique for phase error correction in reflection mode terahertz time-domain spectroscopy

Terahertz time-domain spectroscopy in reflection mode geometry provides valuable surface and subsurface information, making it suitable for a layer analysis, coating, and non-destructive testing applications. The exchanging of the sample and reference’s position introduces a phase error when the position or alignment of the sample is not precisely maintained during measurements. This micrometer order of pitch error (Δx) between the reference and the sample could lead to an inherent error in the phase spectrum of the sample. In the present work, a novel approach, to the best of our knowledge, based on the cross-correlation with an envelope technique, has been demonstrated to reduce the uncertainty in the phase and reveal the hidden characteristic features of the given sample in THz TDS spectroscopy. In conjunction with experimental verification, we have employed a finite element analysis in COMSOL Multiphysics to simulate a misplacement error between a lossy dielectric medium (n=1.2 to 3.0 and k=0 to 0.9) and a reference. We have investigated the impact of varying properties of the lossy dielectric medium on delay measurements using a cross-correlation with an envelope analysis. We illustrated and demonstrated the advantage of our approach by measuring the optical properties of Teflon, quartz, and RDX by correcting the misalignment of the 15.75, 17.55, and 20.70 µm ranges, respectively.

The use of an innovative technique for perforations of the mucous membrane of the maxillary sinus during the sinus lift operation

Introduction. To date, according to WHO, the number of people with a complete absence of teeth is greater than 8% of all the people worldwide. Loss of teeth due to complications of caries treatment, chronic periodontitis and trauma leads to atrophy of the alveolar ridge and that of soft tissues in this area, which in turn complicates the rehabilitation of the patients. According to the literature, in the first year after tooth extraction, the volume of the bone tissue of the alveolar ridge decreases by 40–60%, which greatly complicates the subsequent orthopedic rehabilitation of the patients. Currently, the «gold standard» for increasing the volume of the bone tissue of the alveolar ridge of the upper jaw in the distal section is the sinus lift operation. However, according to the literature, when sinus lift operation is performed, Schneider’s membrane perforation occurs in 7–23% of cases, which in terms, leads to the inability to complete the operation and complications in cases with total perforations of membrane.Purpose of the study. To evaluate the complex rehabilitation of patients with partial secondary absence of teeth and severe atrophy in the lateral sections of upper jaw using the «envelope technique» during open sinus lifting.Materials and methods. In 2020–2022, during a clinical study at the clinic of the Department of maxillofacial and plastic surgery of the Moscow State Medical University named after A.I. Evdokimov, 54 patients who had a history of PPI interventions in the ENT department were treated. All patients underwent bilateral open sinus lifting using enamel matrix proteins or the «envelope technique» for perforation of the Schneider membrane. After 9–12 months, a comprehensive rehabilitation of patients based on dental implants was carried out.Results. The number of extensive (total) perforations of the Schneider membrane in the study group of patients was 50%. As a result of the use of the patented «envelope technique» with the use of enamel matrix proteins, no postoperative complications were observed in patients with total perforation of the Schneider membrane. Taking into account the planned orthopedic design, 292 dental implants were installed in all patients.Conclusion. The method is effective and safe, allowing to rehabilitate patients with missing teeth and severe atrophy in the lateral part of the upper jaw, in case of intraoperative total perforation of the Schneiderian membrane.

Energy loss analyses of amorphous magnetic ribbons by multi-frequency single sheet tester

Due to low values of both thickness and conductivity, Fe-based amorphous soft magnetic ribbon (AR) is an attractive alternative to crystalline silicon steel (CS) for elevated frequencies f up to several kHz. On the other hand, for corresponding tests of losses P, the only standardized method is restricted to just 400 Hz. Recently, we reported “Physically Consistent Loss Testing” (CLT) for loss tests of CS for f up to 10 kHz. Here, we describe an adaptation of a corresponding multi-frequency single sheet tester for AR-applications. The CS single sheet is replaced by six 50 cm long and 17 cm wide ARs, loosely inserted into a paper envelope. This “envelope technique” provides (i) simple sample arrangement in an absolutely flat state, (ii) high repeatability, (iii) robust sensor signals, (iv) avoidance of loss increases due to magneto-mechanical effects, and (v) averaging over thickness variations of ARs through as much as 100 g of sample mass. Here, we report the results of frequency analyses for sinusoidal magnetization in the longitudinal direction for induction up to 1.5 T for f &amp;lt; 1 kHz and 0.4 T for 10 kHz, with P up to 50 W/kg. Anisotropy tests confirm a very weak dominance of the transverse direction. In conclusion, CLT proves to be an effective tool for loss tests on both CS and AR as a physically consistent principle. Therefore, for the ongoing standardization of SST with H-coil, we recommend considering the integration of the “envelope technique” in order to establish rapid and universal multi-frequency loss testing.

Quantifying Morphostructural Evolution of the Eastern Algerian Saharan Atlas (NE, Algeria) Using GIS-based Surface Envelope Technique, Drainage Network Analysis, and Geological Features

This research work focuses on the morphostructural evolution of the eastern end of the Algerian Saharan atlas. The study employs a comprehensive methodology involving the utilization of the surface envelope technique, combined with an analysis of the hydrographic network and geological context. These techniques are integrated within a GIS framework to decipher the current relief characteristics. To interpret the current relief features, two ASTGTM v2 tiles were processed to extract morphometric data. The reconstruction of the original relief requires the generation of the summit level surface, the base level surface and the relief amount maps for 3 different grid sizes (4000m, 1000m and 250m). The respective different grid size maps has allowed determining the initial surface of the reliefs; first before any major vertical erosion, then after a phase of dismantling and finally the recent and sub current morphological aspect. The extraction of the hydrographic network and the elimination of lower than order 5 streams revealed the harmony of the latter with a raised shaped form (mega-horst) which represents the main morphostructural unit. This morphostructure is particularly characterized by outcrops from the Lower Cretaceous outcrops. The ramification of the hydrographic network along the main tectonic accidents has allowed the digging of wide valleys, often described as graben.

Classical TAP vs. I TAP Using the Same Dose of Local Anesthetic in Elective Cesarean Section: A Randomized Controlled Trial.

The effectiveness of postoperative pain control following a Cesarean section influences mother-child attachment, improves early healing, and undoubtedly hastens discharge. Transverse abdominis plane (TAP) and ilioinguinal iliohypogastric (ILIH) blocks have been used to minimize postoperative opioid intake, although their relative effectiveness is unknown. The study aims to determine which procedure was more effective at reducing the need for postoperative rescue analgesics after lower segment Cesarean section (LSCS). TAP block or I TAP (TAP block plus ilioinguinal iliohypogastric nerve block). Both procedures used the same amount of local anesthetic. A sealed envelope technique was used to randomly assign 210 patients who received LSCS into two equal groups to receive either ultrasound (US)-guided TAP block or US-guided ILIH nerve block with US-guided TAP block at the conclusion of the procedure. As per the study protocol, the charge nurse in the postoperative ward gave rescue analgesics to patients who complained of discomfort. At hours 0, 2, 4, 6, 8, 10, and 24 following surgeries, a blinded observer checked on the patient and noted the effectiveness of pain management, the quantity of rescue analgesics used, and patient satisfaction. While there was a substantial decrease in pain score while resting at 2, 3, 4, 8, 12, 16, 20, and 24 postoperative hours in the ITAP group, there was not a significant change in visual analogue scale (VAS) score at the first postoperative hour. However, there was a large delay in the first request for analgesia in the ITAP group (13.15 ± 1.85) as opposed to the TAP group (10.06 ± 1.61) and there was a significant decline in nalbuphine use as well as a higher satisfaction score in the ITAP group. Following LSCS, ITAP block offered better postoperative analgesia than TAP block in terms of quality.

Outcome of Early Active and Late Mobilization following Flexor Tendon Repair in Zone ΙΙ of Hand

The functional outcome of flexor tendon injury after repair depends on multiple factors. Postoperative rehabilitation protocol plays an important role after a good repair for better functional outcomes. The aim of this study is to compare the outcome between early active mobilizations versus late mobilizations after flexor tendon repair in zone-II of hand. This Quasi-experimental (Nonrandomized control trial) was conducted from July 2018 to June 2021. Total 30 patients of flexor tendon injury in Zone-II of hand presented within 3 weeks were divided into two equal groups according to envelope technique, late mobilization (No intervention group) group- A and early active mobilization (Intervention group) group-B. All the flexor tendons were repaired with polypropylene 4/0 double strand score sutures and 6/0 epitendinous continuous sutures. In group-A mobilization started after 3 weeks and in group–B, intervention was given by active mobilization which was started at the day of operation. Buck Gramcko functional criteria and Louisville system were used for assessment of final result after 6 months of surgery. Male was predominant, M: F ratio was 3.3:1. Mean age of the respondent was 32.53±9.86 years. Dominant (Right) hand involvement was 70%. Student and service holder were the common involved group. Nearly three fourth (73%) of them had sharp cutting injury. More than half (53.10%) of the injuries were found in ring and little fingers followed by index (20.30%), middle (20.30%) and thumb (6.30%). Mean time interval between injury and operation was 11 days. Adhesion formation was the commonest complication that was 40% in group A and 20% in group B. More satisfactory outcome (87.50%) was found in group- B (Intervention group), that is patients who received early active mobilization; where the level of satisfactory outcome was less (62.50%) in group-A (Non-intervention group), that is patients who received late mobilization (p-value was significant &lt;0.05). Early active mobilization following repair of flexor tendon in zone II of hand ensures better functional outcome with minimum complication compared to late mobilization. Bangladesh Med J. 2022 Sept; 51(3): 28-36

Methods of periodically non-stationary random processes for vibrations monitoring of rolling bearing with damaged outer race

The vibrations of a rolling bearing with a damaged outer race are analyzed using a method based on periodically non-stationary random processes (PNRPs). PNRPs can be considered as a particular case of poly-periodically non-stationary random processes (PPNRs), which describe the interactions of vibration stochastic rhythms with different periods that are determined based on the characteristic bearing frequencies. A PNRP model for these vibrations is verified using methods for discovering the first- and second-order periodicities. By applying the least squares technique, it is shown that the mean function and variance are time periodic functions, and their basic frequencies are determined. This enables us to calculate the amplitude spectra for the deterministic oscillations and the time changes in the power for the stochastic part. It is shown that the dependencies of the Fourier coefficients for the covariance function on lag have the forms of slowly damped groups. Vibration covariance structures are compared for different fault widths; it is found that high-frequency modulations of the PNRP carrier modulations are narrow-band, and Rice representations are used to model them. The PRNP model of vibrations is then represented in the form of a superposition of the stationary high-frequency components that are jointly periodically non-stationary. The mutual periodical non-stationarity of these components results in variance time changes. Band-pass filtering of the vibration signal is conducted, and the influence of the filter bandwidth on the number and values of the amplitude of the variance harmonics is analyzed. It is shown that PNRP methods for time series processing enable fault detection in cases where the squared envelope and other familiar techniques are ineffective.

Monitoring of ball bearings via vibration analysis and envelope technique for predictive maintenance purposes

Bearings are one of the primary and most crucial machine components in the industry and transportation systems, since they are critical components in these systems, their failure can lead to various losses and significant damages. Despite the advanced stages of development and manufacturing processes, approximately 90% of unplanned machine shutdowns are attributed to bearing failures. These failures can occur in various ways, making it essential to monitor the bearing's deterioration to replace it before it reaches a critical condition for the industry, machine or vehicle's operation. To monitor ball bearing failures, a range of vibration monitoring techniques are employed, encompassing envelope analysis, kurtosis, bi-spectrum, and wavelet analysis. In this case, frequency graphs based in the signals of the bearings inner race will be generated, through a new signal acquisition system, using of envelope analysis by frequency filters, Hilbert Transform and Fast Fourier Transform (FFT). However, detecting and analyzing these signals can be challenging due to weak signals and noise masking vibration patterns. Although current techniques are effective, they have limitations, such as requiring expert analysis, difficulty in detecting early-stage faults, and inability to differentiate between different fault types. Current techniques, such as envelope and wavelet analysis, are effective but have limitations. New technologies and methods, are being explored to improve fault detection and classification, providing early detection of faults and differentiation between different fault types, ultimately reducing the impact of ball bearing failures on machines and industries. This paper proposed to present a study of the ball bearing failure through vibration analysis from early-stage to advanced-stage of damage for predictive maintenance purposes, applying the envelope and FFT together with programming, to enable the identification of defects in the bearing, especially in the inner race, through a signal acquisition system that can explain the presence of the defect through frequency graphs. Thus, obtaining results that show the presence of defects in three different bearings, with gradual defect magnitudes, differentiating these data from an ideal bearing. The next step we will intend to explore the new technologies like machine learning and artificial intelligence, to also analyze all variants of defects in a bearing.

Analysis of the Shoreline Changes using Geoinformatics in Ghoramara Island of Hugli Estuary, West Bengal in India

Conceptual FrameworkCoastal decrepitude is the loss of topographical resources along the coast as a result of silt, temperature fluctuations, tidal shifts, and wave breaking. Hydraulic activity, scraping, abrasion, and erosion are the major causes of erosion; other factors that affect it include the condition of the shore, rocks, joints, fissures, marine chemical reactions, and wave force. ObjectivesThe primary objectives of this study are to analyze the coastline changes between 1972 and 2022 utilizing remote sensing and GIS data and forecast the changes in the shoreline in 2032. MethodsThe study examined coastal areas from 1972 to 2022 using multi-temporal satellite data from Landsat TM and Landsat OLI/TIRS. Shoreline change and the calculations related to it were examined using the Digital Shoreline Analysis System using near-infrared bands and tasseled cap transformation, to determine the rate of change in the shoreline, the study also employed Shoreline Change Envelope and End Point Rate techniques. ResultsCoastal erosion caused substantial damage to the island between 1972 and 2022. The northern, southeastern, and western regions of the coast are seeing the highest levels of coastal erosion. The south coast experiences considerable erosion, whereas the west and southeast coasts experience the least. The EPR of Ghoramara Island has mean, minimum, and maximum changes of -10.59, -4.13, and -35.93, respectively. A notable inshore shift has occurred in the northern portion of Ghoramara, extending from 676 meters to 855 meters. The study also uses tidal gauge records and Revised Local Reference data from the Haldia Gauge Station to track long-term sea level variations. According to the study, Ghoramara Island's shoreline will change by 2032, with the greatest negative changes expected to occur around the island's western and southern borders. ConclusionThe study shows a significant decrease in Ghoramara's shoreline regions between 1972 and 2022, with a 3,000-population shifted from the place in 2016 due to Lohachara's submergence. Changes in the island's morphology and human activities have reduced cultivation. The study suggests increasing mangrove vegetation to combat coastal erosion and prevent further displacement of people to neighboring islands.

Six-Month Soft Tissues Healing after Lower Third Molar Extraction: Comparison of Two Different Access Flaps.

As specific flap designs performed for lower third molar extractions usually influence periodontal healing of the adjacent first and second molars, this study aimed to evaluate the periodontal conditions of these sites after 6 months post-surgery. Forty patients, aged 14-30 years, were included. Surgical extraction of the lower third molar was performed through a flap with papilla detachment (a modified envelope technique with detachment of gingival papilla between the first and second molars) or a trapezoidal flap (characterized by mesial- and distal-releasing incisions). Periodontal parameters at the first and second molar sites were assessed for visible plaque index, bleeding on probing, recession, probing pocket depth, and clinical attachment loss before surgery (T0), one month (T1), and six months after extraction (T2). No statistical differences were found for the plaque and bleeding indexes between the two flaps at each observation time and considering both time intervals. For recession, no statistical differences were found between the two flaps considering the final time interval. For probing pocket depth at the second molar site, both techniques registered a significant increase between T0 and T1, followed by a decrease up to T2. For clinical attachment loss, mean values assessed for the first and second molar sites demonstrated evidently increased values between T0 and T1, followed by moderate decreases up to T2. Considering short (T1) and mid-term (T2) follow-ups, a specific flap design does not seem to particularly influence periodontal healing six months after surgery.

Utilizing Ground-Penetrating Radar for Water Leak Detection and Pipe Material Characterization in Environmental Studies: A Case Study

Detecting and mapping subsurface utilities in urban areas is crucial for identifying defects or damages in drinking and sewage pipes that can cause leaks. These leaks make it difficult to accurately characterize the pipes due to changes in their reflective properties. This study focused on detecting leaks originating from underground pipes and distinguishing between these various types of pipes. It also aimed to create a visual fingerprint model that displays the reflection characteristics of these pipes during different leak conditions, enabling efficient maintenance and handling procedures on the pipes. To achieve this, a finite-difference time-domain (FDTD) method was used to simulate two types of pipe materials with and without leak areas to construct different scenarios. Additionally, a ground-penetrating radar (GPR) field survey was conducted using a 600 MHz antenna in a part of the El Hammam area on Egypt’s northwest coast. The simulated images produced with numerical modeling were compared with the radar profiles obtained using GPR at particular locations. The numerical simulations and radar profiles demonstrated the noticeable influence of water leaks from the different pipes, wherein the reflection of saturated soil waves was interrupted due to the presence of saturated soil. Envelope and migration techniques were employed in a new application to accurately distinguish between different pipe types, specifically focusing on leak areas. The strong correlation between the real radar profile and the specific signal of a water pipe leak in the simulated models suggests that GPR is a reliable non-destructive geophysical method for detecting water pipe leaks and distinguishing between the different pipe materials in various field conditions. The simulated models, which serve as image-matching fingerprints to identify and map water pipe leaks, help us to comprehend reality better.

Comparison of success rate of abducted and neutral arm position for right infraclavicular subclavian vein cannulation under real-time ultrasound guidance in patients undergoing elective neurosurgery under general anesthesia.

Classically subclavian vein catheterization is done in neutral arm position; recently, it has been done in different arm positions to compare success rate and catheter misplacement. There is a paucity of literature for comparing abducted and neutral arm position for right infraclavicular subclavian vein cannulation. Comparison of success rate of abducted and neutral arm position for right infraclavicular subclavian vein cannulation under real-time ultrasound guidance in patients undergoing elective neurosurgery under general anesthesia. Randomized comparative study. After approval from Institutional Review Board and Ethical Committee, 100 patients of 18-70 years of age, of either sex, posted for elective neurosurgery under general anesthesia, requiring right subclavian vein cannulation were included in our study. They were randomly divided into two groups: abducted arm position (group 1-AG) and neutral arm position (group 2-NG) using sealed envelope technique. First attempt success rate was higher in AG group compared to NG group (P value- 0.741). Times taken (seconds) for cannulation in NG and AG group, catheter misplacement and hematoma (P value- 0.37, P value- 0.37, P value- 1, respectively) were lesser in AG Group. For USG-guided infraclavicular subclavian vein cannulation, abducted arm position, and neutral arm position in terms of first attempt success rate, number of attempts and associated complications has comparable results; however, further studies with larger group of patients are required to assess the overall advantage of abducted arm position over neutral arm position.

Short-Term Reliability Assessment of Integrated Power-Gas Systems With Hydrogen Injections Using Universal Generating Function

Injecting alternative gas (e.g., green hydrogen from wind generation) into the gas system is a promising way to decarbonize the energy sector. However, the fluctuating renewable generation could lead to time-varying alternative gas injections. Then, the gas composition in the gas system may become uncertain, increasing the short-term risk of the integrated power-gas systems during the operation. This paper proposes a short-term reliability assessment approach for IPGS with alternative gas injections. First, the multi-performance and multi-state universal generating functions (UGF) are constructed to efficiently model the short-term reliability of the power-to-gas facility and the wind farm, respectively. Then, a reliability management UGF operator is proposed to minimize both load shedding and gas security violation. A set of novel reliability indices is proposed to comprehensively assess the gas security violations under uncertain gas compositions. Moreover, an analytical short-term reliability assessment approach is proposed, where the state-based sequential approximation and state-based McCormick envelope techniques are tailored and embedded. By optimizing the solution order by the system states, the nonconvexities in the reliability management optimization problem can be handled tractably without increasing the computation burden. Finally, the IEEE 24 bus Reliability Test System and the Belgium gas system are used to validate the proposed approach.