Minimization Technique Research Articles

One‐Dimensional Variational Ionospheric Retrieval Using Radio Occultation Bending Angles: 1. Theory

AbstractA new one‐dimensional variational (1D‐Var) retrieval method for ionospheric GNSS radio occultation (GNSS‐RO) measurements is described. The forward model implicit in the retrieval calculates the bending angles produced by a one‐dimensional ionospheric electron density profile, modeled with multiple “Vary‐Chap” layers. It is demonstrated that gradient based minimization techniques can be applied to this retrieval problem. The use of ionospheric bending angles is discussed. This approach circumvents the need for Differential Code Bias (DCB) estimates when using the measurements. This new, general retrieval method is applicable to both standard GNSS‐RO retrieval problems, and the truncated geometry of EUMETSAT's Metop Second Generation (Metop‐SG), which will provide GNSS‐RO measurements up to about 600 km above the surface. The climatological a priori information used in the 1D‐Var is effectively a starting point for the 1D‐Var minimization, rather than a strong constraint on the final solution. In this paper the approach has been tested with 143 COSMIC‐1 measurements. We find that the method converges in 135 of the cases, but around 25 of those have high “cost at convergence” values. In the companion paper (Elvidge et al., 2023), a full statistical analysis of the method, using over 10,000 COSMIC‐2 measurements, has been made.

Impact of Different Methods of Wheat Cultivation on the Occurrence of Carabidae Family Representatives (Carabidae, Coleoptera)

The aim of this study was to evaluate the impact of different methods of wheat cultivation on the occurrence of Carabidae (Coleoptera, Carabidae). The collection was carried out during a three-year period from 2016 to 2018, on research areas in Borovce, which belong to the Research Institute of Plant Production (VÚRV) in Piešťany. The collection of epigeic material was done in five variants: V1: mulching technique; V2: conventional technique; V3: minimization technique; V4: no-till technique; and ECO: ecological technique. During the three-year period, we obtained 11,362 specimens from eight epigeic groups. Out of all the epigeic groups, the dominant order was Coleoptera with the number of individuals 7593. We addressed the Coleoptera order in more detail. It was represented by six families, of which the Carabidae family was dominant. We recorded 6656 specimens from the mentioned family, of which we determined 20 species. The eudominant species were Pterostichus melanarius (Illiger, 1798) and Pseudoophonus rufipes (DeGeer, 1774) throughout the whole period on all types of variants. Based on the specimens obtained, we calculated the values of dominance, frequency, species similarity of communities, diversity of communities and statistically evaluated the correlation of the impact of meteorological factors and the occurrence of Carabidae.

Sun-Cross Running Suture Combined with Transverse to Longitudinal Skin Closure to Correct Severe Inverted Nipple.

Inverted nipple deformity presents an unsatisfactory appearance that may induce an unpleasant sex life, but can also be associated with psychological discomfort and increased the functional problems, such as local irritation and inflammation. Multiple techniques have been used to correct inverted nipples, but they mostly lead to different problems such as deficiency of the nerve or duct, recurrence of the inverted nipple, and hypopigmented scars in the areola. To minimize complications and maintain the stability of the reconstructed nipple, we presented a minimal incision technique that designed four 3-mm-sized horizontal microincisions, which ran a sun-cross through the periphery and the core of the nipple to push the nipple together, then a vertical suture ran longitudinal to close the transverse incision to stabilize the projection. This technique was performed in 71 patients classified as grade II or III of the inverted nipples, comprising 53 congenital cases and 18 patients with acquired deformity. Thirty-four patients had bilateral inverted nipples, and 37 patients had unilateral inverted nipple. During a mean follow-up period of 15months, 70 corrected nipples remained raised without recurrence, and one nipple was found retracted at the outpatient clinic after 3months. There were no serious complications associated with surgery regarding nipple necrosis, seven patients got temporary swelling, two patients got infected after touching water, three patients got extravasated blood, eight patients indicated that they touched scar under the nipple, and two patients reflected nipple dysesthesia. In the 15months follow-up, the patients with Grade II nipple inversion maintained a nipple average height of 9.54 ± 0.95, and the patients with Grade III nipple inversion maintained a nipple average height of 9.19 ± 1.09, and 86.63% of patients were satisfied with their results. This is a simple, safe, effective and reliable technique that should be considered, providing sustained results over the long-term follow-up period with a high rate of stable eversion and low incidence of ischemia, necrosis, scarring and dysesthesia. The vertical scar of the transverse incision closure leads to an esthetic appearance without apparent scarring and minimizes the risk of an altered nipple sensation. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Radiofrequency electromagnetic radiation exposure assessment, analysis, computation, and minimization technique in 5G networks: A perspective on QoS trade-offs

Radiofrequency electromagnetic radiation exposure assessment, analysis, computation, and minimization technique in 5G networks: A perspective on QoS trade-offs

AI and semantic ontology for personalized activity eCoaching in healthy lifestyle recommendations: a meta-heuristic approach

BackgroundAutomated coaches (eCoach) can help people lead a healthy lifestyle (e.g., reduction of sedentary bouts) with continuous health status monitoring and personalized recommendation generation with artificial intelligence (AI). Semantic ontology can play a crucial role in knowledge representation, data integration, and information retrieval.MethodsThis study proposes a semantic ontology model to annotate the AI predictions, forecasting outcomes, and personal preferences to conceptualize a personalized recommendation generation model with a hybrid approach. This study considers a mixed activity projection method that takes individual activity insights from the univariate time-series prediction and ensemble multi-class classification approaches. We have introduced a way to improve the prediction result with a residual error minimization (REM) technique and make it meaningful in recommendation presentation with a Naïve-based interval prediction approach. We have integrated the activity prediction results in an ontology for semantic interpretation. A SPARQL query protocol and RDF Query Language (SPARQL) have generated personalized recommendations in an understandable format. Moreover, we have evaluated the performance of the time-series prediction and classification models against standard metrics on both imbalanced and balanced public PMData and private MOX2-5 activity datasets. We have used Adaptive Synthetic (ADASYN) to generate synthetic data from the minority classes to avoid bias. The activity datasets were collected from healthy adults (n = 16 for public datasets; n = 15 for private datasets). The standard ensemble algorithms have been used to investigate the possibility of classifying daily physical activity levels into the following activity classes: sedentary (0), low active (1), active (2), highly active (3), and rigorous active (4). The daily step count, low physical activity (LPA), medium physical activity (MPA), and vigorous physical activity (VPA) serve as input for the classification models. Subsequently, we re-verify the classifiers on the private MOX2-5 dataset. The performance of the ontology has been assessed with reasoning and SPARQL query execution time. Additionally, we have verified our ontology for effective recommendation generation.ResultsWe have tested several standard AI algorithms and selected the best-performing model with optimized configuration for our use case by empirical testing. We have found that the autoregression model with the REM method outperforms the autoregression model without the REM method for both datasets. Gradient Boost (GB) classifier outperforms other classifiers with a mean accuracy score of 98.00%, and 99.00% for imbalanced PMData and MOX2-5 datasets, respectively, and 98.30%, and 99.80% for balanced PMData and MOX2-5 datasets, respectively. Hermit reasoner performs better than other ontology reasoners under defined settings. Our proposed algorithm shows a direction to combine the AI prediction forecasting results in an ontology to generate personalized activity recommendations in eCoaching.ConclusionThe proposed method combining step-prediction, activity-level classification techniques, and personal preference information with semantic rules is an asset for generating personalized recommendations.

Two-way adjustable double-knots intrascleral fixation and single sclerotomy looping technique: a novel minimal invasive adjustable intraocular lens fixation technique

BackgroundIOL fixation without capsular support presents challenges for surgeons. Although innovative techniques were developed to address subluxated IOLs, adjustable IOL fixation methods are seldom reported. We introduce a novel two-way adjustable double-knots intrascleral fixation combined with single sclerotomy looping technique for fixing intraocular lenses (IOL) or IOL-capsular bags.MethodsA bent 30-gauge needle threaded with 8 − 0 polypropylene was introduced into the eye. A gripping forceps assisted the haptic looping. Two overhand knots were made with 8 − 0 polypropylene thread. The knots were incarcerated into a scleral tunnel made by a 30-gauge needle, with two ends of the thread left at each side of the tunnel. The IOL was adjusted to the premium position with adequate tension by pulling either end of the threads. The study included 19 eyes with aphakia, subluxated IOL-capsular bags, or subluxated crystalline lenses. The mean followed up period was 18.9 ± 7.1 months with evaluations of uncorrected visual acuity (UCVA), intraocular pressure, slit-lamp examination, and swept-source optical coherence tomography of the anterior segment.ResultsUCVA increased from 1.28 ± 0.74 at baseline to 0.44 ± 0.51 (logMAR) at final visit (P < 0.001). All IOLs were fixed well-centered. The mean IOL tilt was 3.5°±1.1°. Postoperative complications included transient IOP elevation (15.8%), hypotony (10.5%), and cystoid edema (5.3%) which resolved within 4 weeks.ConclusionsWe presented a novel adjustable technique for IOL fixation, which stabilize IOLs by using an intrascleral double-knots structure. This technique minimized surgical manipulations by using a single sclerotomy looping technique without large conjunctival dissection and scleral flap creation. The technique offers a reliable and optimal IOL positioning and improved visual outcomes in patients undergoing scleral fixed IOL implantation.

Boosting Lightweight Sentence Embeddings with Knowledge Transfer from Advanced Models: A Model-Agnostic Approach

In this study, we investigate knowledge transfer between two distinct sentence embedding models: a computationally demanding, highly performant model and a lightweight model derived from word vector averaging. Our objective is to augment the representational power of the lightweight model by exploiting the sophisticated features of the robust model. Diverging from traditional knowledge distillation methods that align logits or hidden states of teacher and student models, our approach uses only the output sentence vectors of the teacher model for the alignment with the student models’s word vector representations. We implement two minimization techniques for this purpose: distance minimization and distance and perplexity minimization Our methodology uses WMT datasets for training, and the enhanced embeddings are validated via Google’s Analogy tasks and Meta’s SentEval datasets. We found that our proposed models intriguingly retained and conveyed information in a model-specific fashion.

Fast Kötter–Nielsen–Høholdt interpolation over skew polynomial rings and its application in coding theory

Skew polynomials are a class of non-commutative polynomials that have several applications in computer science, coding theory and cryptography. In particular, skew polynomials can be used to construct and decode evaluation codes in several metrics, like e.g. the Hamming, rank, sum-rank and skew metric. We propose a fast divide-and-conquer variant of Kötter–Nielsen–Høholdt (KNH) interpolation algorithm: it inputs a list of linear functionals on skew polynomial vectors, and outputs a reduced Gröbner basis of their kernel intersection. We show, that the proposed KNH interpolation can be used to solve the interpolation step of interpolation-based decoding of interleaved Gabidulin codes in the rank-metric, linearized Reed–Solomon codes in the sum-rank metric and skew Reed–Solomon codes in the skew metric requiring at most O~sωM(n)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\widetilde{O}}\\left( s^\\omega {\\mathfrak {M}}(n)\\right) $$\\end{document} operations in Fqm\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\mathbb {F}}_{q^m}$$\\end{document}, where n is the length of the code, s\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$s$$\\end{document} the interleaving order, M(n)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\mathfrak {M}}(n)$$\\end{document} the complexity for multiplying two skew polynomials of degree at most n, ω\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\omega $$\\end{document} the matrix multiplication exponent and O~·\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\widetilde{O}}\\left( \\cdot \\right) $$\\end{document} the soft-O notation which neglects log factors. This matches the previous best speeds for these tasks, which were obtained by top–down minimal approximant bases techniques, and complements the theory of efficient interpolation over free skew polynomial modules by the bottom-up KNH approach. In contrast to the top–down approach the bottom-up KNH algorithm has no requirements on the interpolation points and thus does not require any pre-processing.

Novel technique of vibration minimization during hard machining

AbstractThis research paper explores the performance of electrorheological fluids, widely known as smart fluids, which are popular because they experience immediate changes in their characteristics when applied to exterior magnetic or electric field. On application of high voltage, the ER fluid alters its form to semisolid from viscous liquid within a few milliseconds, which is reversible. The reversible nature of ER fluid was employed to absorb vibrations during hard machining. In this research, the consequence of the application of electric field to the ER characteristics of numerous non‐Newtonian fluids with an accumulation of TiO2 and Al2O3 nano elements are investigated. The purpose of this research is to discover the ER sample, which has the highest viscosity, highest breakdown voltage, but less sedimentation. So the selected sample can be used in ER dampers for the purpose of shock absorption. The ER fluid behaves as a mainspring with nonlinear vibration features that are managed by an arrangement of ER fluid, the structure of plunger, and the constraints of applied electric field. In this research, we have employed steel metallic specimens made from EN24T of 302BHN and the machining experiments are conducted to attain the shape parameters that can reduce the tool vibration and help improve the process of cutting at the time of machining with minimum application of fluid utilizing hard metal inserts. In this work, cutting tool parameters were analyzed like cutting force, tool wear, tool vibration amplitude, and surface roughness. It was observed that ER damper has shown its better performance at 5KV. At 5KV, cutting force was the least, tool wear was the least, tool vibration amplitude was the least, and surface roughness was the least. The use of an ER fluid damper decreases tool vibrations and successfully enhances machining performance. The machining industry will be benefited with commercialization of this technique.

Minimally Invasive Approach to Access Vessels for Microvascular Anastomosis in Head and Neck Reconstruction.

To describe our technique, review indications, and evaluate the outcomes of the minimal access approach for recipient vessel identification in microvascular tissue transfer. Retrospective chart review of all patients who underwent microvascular reconstruction using the minimal access technique between 2015 and 2021. We report 236 cases, comprising 214 patients with a mean age of 60.2 years (3-88). The most common primary defect sites were the mandible (22.6%), cranium (14%), maxilla (13.2%), skull base (12.8%), and nose/nasal cavity (10.6%). Indications for free flap reconstruction included head and neck cancer extirpation (32.2%), osteoradionecrosis (29.7%), acquired deformity (14.0%), chronic wound (11.9%) and oral motor dysfunction (7.2%). Free flap donor sites used were the anterolateral thigh (84.3%), fibula (7.2%), and radial forearm (6.4%). Vessels utilized include superficial temporal (49.8%), facial (38.3%), angular (11.1%), and transverse cervical (0.4%). The overall complication rate was 14% (n = 33), with surgical complications at the recipient site accounting for 67.6% (n = 25). Flap failure occurred in 3.4% of procedures. Prior head and neck surgery and free flaps were associated with an increased risk of major recipient site complications (n = 20, p = 0.0257 and n = 14, p = 0.0117, respectively). Minimal access techniques allow consistent recipient vessel identification for microvascular-free tissue transfer. These approaches may be utilized in reconstructing a broad range of head and neck defects, are low morbidity, and contribute to an overall shorter length of stay. 2 Laryngoscope, 134:2177-2181, 2024.

General weighted cumulative residual (past) extropy of minimum (maximum) ranked set sampling with unequal samples

The general weighted cumulative residual extropy (GWCRJ) and general weighted cumulative past extropy (GWCPJ) are introduced in this article. There are some results in relation to GWCPJ and GWCRJ. We take into account GWCRJ-based uncertainty measures for the minimal ranked set sampling technique with unequal samples (minRSSU). Additionally, we take into account GWCPJ-based uncertainty measures for the maximum ranked set sampling technique with unequal samples (maxRSSU). Stochastic comparison for simple random sampling (SRS) is discussed. We looked at the monotone properties of minRSSU and maxRSSU as well as stochastic comparison. The empirical estimators of GWCPJ and GWCRJ are obtained and a simulation study for comparing the proposed estimator will be given involving the proposed ranked set sampling schemes under perfect ranking.

Multiple Mini Incision Technique for Sural Nerve Harvest: When to Add a Fibular Incision Based on a New Surgical Classification

Sural nerve is the most common nerve used as a source for nerve grafting. Open harvest with longitudinal incisions produces unsightly scars, and this have led to development of less invasive techniques using endoscopes, nerve stripper, and mini-incisions. Several anatomical classifications have also been proposed due to the variations in the anatomy of the sural nerve. A simple and practical surgicoanatomical classification of the sural nerve based on which we have refined our minimal access technique, the multiple mini-incision technique for sural nerve harvest is proposed. In this technique, the incisions required for harvest of the sural nerve are standardized and predictable. A fibular incision is required when the sural nerve has major contribution from the common peroneal nerve. We have found this a simpler and reliable technique of harvest of sural nerve in nerve reconstructive surgery.

Tracheal tubes intracuff pressure difference between neutral head-neck position and lateral rotation in patients with tracheal intubation

BackgroundTracheal tubes (TT) cuffs seal the airway to facilitate positive pressure ventilation and prevent aspiration due to subglottic secretions. Changes in head-neck position can affect TT intracuff pressure. An increase or decrease in TT intracuff pressure can cause many morbidities. The purpose of this study was to determine the effect of lateral head-neck rotation on TT intracuff pressure. MethodsForty (40) patients aged 18–64 years undergoing elective surgery under general anesthesia were selected in this study. After tracheal intubation, the TT cuff was inflated with a minimal occlusive volume technique. The TT was placed on the right side of the mouth. Changes in TT intracuff pressure were assessed before and after the position change. TT intracuff pressure was measured with a cuff inflator in the neutral head position. After lateral head-neck rotation (60°), the intracuff pressure was remeasured. ResultsThe mean intracuff pressure increased from 25.5 + 1.64 to 29.4 + 1.71 cmH2O after lateral head-neck rotation (p = 0.000). There was a significant difference between neutral position and lateral head rotation (p < 0.05). The use of a minimal occlusive volume technique with a volume of 4–7 cc was able to produce TT intracuff pressure between 22 and 28 cmH2O (normal range 20–30 cmH2O). The difference in TT intracuff pressure after lateral head-neck rotation was 3.9 ± 1.31 cmHO2. ConclusionTracheal tube intracuff pressure is significantly higher after the head-neck position change from neutral to lateral rotation. Measurement of intracuff pressure after lateral head rotation is beneficial to avoid possible adverse effects of position-related pressure changes.

Comparison of a minimal invasive technique micro-marsupialization versus surgical excision for mucocele of lower lip.

Objective: To compare the efficacy of micro-marsupialization with surgical excision for the treatment of mucoceles originating from the minor salivary glands of the lower lip. Our primary endpoints were the mean procedural time and the duration of post-operative healing. Study Design: Randomized Controlled Trial (RCT). Setting: Department of Oral and Maxillofacial Surgery, Faisalabad Medical University, Faisalabad. Period: 1st July 2022 to 31th Dec 2022. Material &amp; Methods: We enrolled a total of 60 patients, with 30 in each group (Group X: micro-marsupialization, Group Y: surgical excision). Random allocation was performed using a lottery method. Procedural time (in minutes) and post-operative healing duration (in days) were recorded for both groups, with follow-up assessments conducted over a 3-month period. Results: The study comprised 60 patients (40 males and 20 females) with a mean age of 34.60±10.15 years in Group X and 36.03±9.25 years in Group Y. In Group X, the mean surgical time was 6.23±0.935 minutes, while in Group Y, it was 34.70±2.493 minutes. A statistically significant difference in surgical time was observed between the two groups (p 0.0001). Regarding post-operative healing, Group X had a mean duration of 4.67±0.844 days, while Group Y had a mean duration of 6.57±0.504 days. A statistically significant difference was also noted in post-operative healing duration between the two groups (p 0.008). Conclusion: This study underscores the superiority of micro-marsupialization over surgical excision as a treatment option for mucoceles originating from the minor salivary glands of the lower lip. Micro-marsupialization offers several advantages, including significantly shorter procedural times and faster post-operative healing periods.

Hysteroscopy as a Therapeutic Tool: A Vision to Spare the Uterus in Premenopausal Abnormal Uterine Bleeding (AUB)/Heavy Menstrual Bleeding (HMB), an Update.

Heavy menstrual bleeding (HMB) or abnormal uterine bleeding (AUB) is a common cause of gynecological complaints in perimenopausal women. The treatment chosen by most of the women having HMB/AUB in the perimenopausal age group when medical therapy fails is hysterectomy, which unfortunately has significant issues related to safety and long-term quality of life apart from being a burden on the health care system and cost to patients. Minimal access surgical techniques like hysteroscopic targeted therapies are available which are conservative and spare the uterus and major surgery and its complications and sequelae. Hysteroscopic management of HMB is a minimally invasive and targeted approach in diagnosing and treating the pathological lesions causing the symptoms and not radical like hysterectomy which has more chances of occurrence of adverse events both intra and postoperatively. In terms of health-related quality of life, women suffering from HMB who underwent a hysteroscopic conservative approachhad better scores when compared to those with hysterectomy. The present review aims to review the evidence generated to compare the two surgical modalities, hysteroscopic targeted therapyand hysterectomy, in terms of their effectiveness, safety, and effect on the quality of life of these perimenopausal women having HMB/AUB.

Endoscopic Chemocauterization with Trichloroacetic Acid for Congenital or Recurrent Tracheoesophageal Fistula in Children with Esophageal Atresia: Experience from a Tertiary Center

BackgroundRecurrent tracheoesophageal fistula (rTEF) is a well-known complication after surgery of EA, occurring in roughly 3–10% of the patients. Recent studies have highlighted safety and efficacy of endoscopic management of recurrent TEF. The aim of this study was to evaluate the efficacy of chemocauterization with trichloroacetic acid (TCA) in rTEF and congenital tracheoesophageal fistula (cTEF). MethodsRetrospective chart review of consecutive patients with recurrent or congenital TEF who underwent endoscopic chemo-cauterization between 2018 and 2022 at a tertiary center. Children diagnosed with TEF who underwent primary or secondary endoscopic treatment were included. Median follow up time was 19 months for rTEF and 33 months for cTEF. ResultsDuring the study period, 18 patients were treated endoscopically by chemocatuerization with TCA at our institution. Treatment of recurrent TEF was successful in 13 of 14 patients (93%) Treatment of congenital TEF was successful in 2 of 4 patients (50%). In 14 patients, closure was seen after 1–2 treatments. There were no serious adverse reactions or complications to the endoscopic treatment of TEF. ConclusionEndoscopic chemocauterization is a minimal invasive technique with low morbidity and high success rate and may be considered as primary treatment for recurrent TEF. Level of evidenceIII.

Review of Sonic Boom Prediction and Reduction Methods for Next Generation of Supersonic Aircraft

The reduction of sonic boom levels is the main challenge but also the key factor to start a new era of supersonic commercial flights. Since 1970, a FAA regulation has banned supersonic flights overland for unacceptable sonic booms at the ground, and many research studies have been carried out from that date to understand sonic boom generation, propagation and effects, both on the environment and communities. Minimization techniques have also been developed with the attempt to reduce sonic boom annoyance to acceptable levels. In the last 20 years, the advances in both knowledge and technologies, and companies and institutions’ significant investments have again raised the interest in the development of new methods and tools for the design of low boom supersonic aircraft. The exploration of unconventional configurations and exotic solutions and systems seems to be needed to effectively reduce sonic boom and allow supersonic flight everywhere. This review provides a description of all aspects of the sonic boom phenomenon related to the design of the next generation of supersonic aircraft. In particular, a critical review of the prediction and minimization methods found in the literature, aimed at identifying their strengths, limitations and gaps, is made, along with a complete overview of disruptive unconventional aircraft configurations and exotic active/passive solutions to boom level reduction. The aim of the work is to give a clear statement of state-of-the-art sonic boom prediction methods and possible reduction solutions to be explored for the design of next low-boom supersonic aircraft.

Laparoscopic Completion Total Gastrectomy for Remnant Gastric Cancer Compared to Laparoscopic Total Gastrectomy in Short- and Medium-Term Results.

Introduction: The incidence of remnant gastric cancer is increasing in recent years. The advantages of minimally invasive surgery for gastric cancer are well established. However, laparoscopic completion total gastrectomy for remnant gastric cancer harbors difficulties due to adhesions, changed configuration of the anatomical organs, and changes on the lymphatic flow. We aim to investigate the feasibility, safety, and the short-term outcomes of laparoscopic completion total gastrectomy compared to laparoscopic total gastrectomy. Materials and Methods: All patients who underwent total gastrectomy from January 2018 to December 2021 at Shamir Medical Center were included in the study. Patients were divided into two groups-completion gastrectomy and total gastrectomy. The groups were compared for demographics, operative, and clinical outcomes. Results: Overall, 22 patients were included in the study. Eight were completion gastrectomy following subtotal gastrectomy for malignancy and 14 were primary total gastrectomy. All operations were performed by minimal invasive surgery technique. Average age was 64 years, with no differences in gender. Two major intraoperative complications were noted in completion group (25% versus 0%, P = .12). Both length of surgery (3:03 versus 3:40, P = .049) and length of stay (7 days versus 9 days, P = .5) were shorter in completion group. There were fewer postoperative complications (12.5% versus 28.5%, P = .61). Average number of harvested lymph nodes was significantly lower in completion group (10 versus 33, P = .002). Conclusion: Laparoscopic completion total gastrectomy for remnant gastric cancer is safe and feasible having comparable oncological surrogate's parameters and recurrence profile. Clinical Registration Number: 0015-22-ASF.

Probable low-frequency quasi-periodic oscillations in blazars from the ZTF survey

ABSTRACT We investigate the possible presence of quasi-periodic oscillation (QPO) signals in 2103 blazars from the Zwicky Transient Facility (ZTF) time-domain survey. We detect a low-frequency QPO signal in five blazars observed over these 3.8-yr-long optical r-band ZTF light curves. These periods range from 144 to 196 d detected at ≳4σ significance levels in both the Lomb–Scargle periodogram and weighted wavelet Z-transform analyses. We find consistent results using the phase dispersion minimization technique. A similar peak is detected in the g-band light curves at a slightly lower significance of 3σ. Such nearly periodic signals on these time-scales in optical wavebands most likely originate from a precessing jet with high Lorentz factor, closely aligned to the observer’s line of sight or the movement of plasma blobs along a helical structure in the jet.

Thermal damage analysis of sub-surface soft tissue sarcoma for indocyanine green mediated photothermal cancer therapy

Photothermal therapy is a minimal invasive technique to treat tumors situated near the skin or other light accessible organs. Here, a photothermal agent is delivered to tumor either intratumorally or intravenously and the tumor is irradiated with near infrared (NIR) radiation to generate heat for thermal damage of tumor. In this paper, thermal damage of soft tissue sarcoma, a type of sub-surface forearm tumor, is evaluated for photothermal therapy using numerical simulations. Indocyanine green (ICG) is used as photothermal agent and the effect of various spatial distributions and doses of ICG for sub surface tumors located at various depths (3–6 mm) were investigated. Further, numerical simulation is validated experimentally through tumor-tissue mimicking phantoms. Computations were performed in MATLAB software using Lattice Boltzmann method and validated through experiments using tumor-tissue mimicking phantoms. Results show that the thermal damage region (damage parameter (Ω) of magnitude 4.6) was enlarged on increasing the concentration of ICG while it got shrunk for the deeper tumors. Computations reveal that ICG concentration of 50 μg/mL is optimum, for intravenous distribution, for photothermal therapy with minimal damage to surrounding tissue. It is found that irradiation duration of more than 900 s is required to achieve the complete damage of tumor. For the case of deeper tumors, about 1200 s of exposure is required, at irradiation intensity of 0.25 W/cm2. This study provides a numerical approach to determine therapeutic parameters and demonstrates the thermal damage for subsurface tumors through ICG mediated photothermal therapy by proper selection of therapeutic parameters.