Original Procedure Research Articles

A novel Lax–Wendroff type procedure of two-derivative time-stepping schemes for Euler and Navier–Stokes equations

In this paper, we developed a novel Lax–Wendroff (LW) type procedure of two-derivative time-stepping schemes for the Euler and Navier–Stokes equations. The explicit two-derivative time-stepping schemes, including the two-derivative Runge–Kutta schemes and variable step size two-derivative multistep schemes, are proposed and the optimized time-stepping schemes are determined by the strong stability preserving theory. The novel LW procedure greatly simplifies the intricate symbolic calculations of the original LW procedure, particularly for the Navier–Stokes equations. The novel LW procedure also ensures both the order accuracy and numerical stability compared to the original LW procedure. Moreover, we presented a simplified positivity-preserving limiter for LW procedure, enabling the temporal schemes to handle demanding computations. When employing high-order spatial methods, numerical tests highlighted that two-derivative time-stepping schemes utilizing the novel LW procedure effectively improve the stability and computational efficiency compared to the Runge–Kutta schemes.

Latarjet procedure: open with screws or arthroscopic with cortical-buttons? A retrospective cohort comparison of outcomes and complications

The original Latarjet-Patte procedure is a reliable procedure to treat traumatic anterior shoulder instability. However, attempts to reduce possible complications have led to the emergence of modified techniques. More prominently are the arthroscopic approach and the use of cortical-buttons for coracoid fixation. To date, limited research is available directly comparing the simultaneous use of these two modifications to the original Latarjet-Patte technique. The purpose of this paper is to compare clinical and radiologic outcomes and complications between open Latarjet with screws and arthroscopic Latarjet with cortical-buttons for traumatic anterior shoulder instability. A multicenter retrospective cohort study of medical records and imaging studies of two groups of patients, with two years of follow-up, who underwent either one of two variations of the Latarjet procedure: open approach with screws (open-screw group) or arthroscopic approach with cortical buttons (scope-button group). Group homogenization was assured by statistical comparison of 14 baseline independent variables as well as multiple regression analysis to assess confounding factors. The primary outcome was the Rowe scale at 24 months after surgery, for which the MCID value of 9.7 was used. Secondary outcomes were recurrence of instability; graft positioning; the Rowe scale at other points in time; and complications. Thirty-eight patients were evaluated in the open-screw group and 44 in the scope-button group, with a 24-month follow-up. All but one patient in each group achieved the MCID from pre- to postoperative Rowe score. The Rowe score did not differ between groups during any of the assessment times. There was no difference regarding graft vertical (p = 0.620) or horizontal (p = 0.280) positioning. There was one recurrence in each group: a dislocation in the open-screw group (p = 0.463) and a subluxation in the scope-button group (p > 0.999). Other complications happened exclusively in the scope-button group: neuropraxis (n = 1; p > 0.999), infection (n = 2; p > 0.999), graft fracture (n = 1; p > 0.999) and graft migration (n = 2; p > 0.999). Multiple regression analysis did not observe influence from any of the potential confounding factors on the final results. At early follow-up, arthroscopic Latarjet with cortical-buttons yielded similarly good clinical and radiologic results as the conventional open Latarjet with screws.

Glycemic Laboratory Values Are Associated With Increased Length of Stay and 90-Day Revision Risk Following Surgical Management of Adult Spinal Deformity

Diabetes mellitus (DM) is a common comorbidity among patients undergoing spinal fusion for adult spinal deformity (ASD) surgery. An elevated Hemoglobin A1c (HbA1c) and elevated postoperative glucose have been shown to increase the risk of complications following spine and other orthopaedic surgeries; however, data is limited for ASD. To investigate glycemic control and ASD surgery to inform surgical decision making, medical optimization, and patient education. Retrospective cohort. Total of 106 adult patients undergoing surgical correction for ASD with an HbA1c drawn within six months preoperatively or two weeks postoperatively and valid plasma glucose levels throughout postoperative hospital stay. Length of stay, 90-day wound complication, 90-day readmission, 90-day revision. All patients undergoing spinal fusion of seven or more levels between 2021 and 2023 at two large academic medical centers were identified using institutional data acquisition software. Medical charts were then manually reviewed to obtain and confirm demographic, laboratory, and surgical characteristics and outcomes. Laboratory characteristics included preoperative HbA1c, mean postoperative glucose (PG), and maximum PG. Surgical characteristics and outcomes included procedure time, estimated blood loss (EBL), length of inpatient stay (LOS), transfusion requirement, 90-day complications, 90-day revision, and 90-day readmission. Bivariate analysis was performed followed by simple and multiple regression analysis. Odds ratios were established relative to the laboratory threshold values informed by receiver operating characteristics. Of 872 original procedures identified, 106 patients (12.2%) were adults with preoperative HbA1c and postoperative plasma glucose measurements who underwent surgery for a diagnosis of ASD. Median patient age was 67 years (IQR 59-72 years), 59 (55.7%) were female, and 96 (90.6%) were of Caucasian race. Median LOS was 7 days (IQR 5-10 years) and median HbA1c was 5.9% (IQR 5.3%-6.5%). Higher preoperative HbA1c was correlated with increased LOS (R=0.22, P=0.023). The odds ratio for patients requiring extended LOS was 2.49 (95% CI 1.06-5.86, P=0.034) for those with HbA1c ≥6.3%. Multiple regression analysis of LOS identified HbA1c [B= 1.51 (95% CI 0.32-2.70), P=0.013] as a positive predictor of LOS and mean PG [B= -0.05 (95% CI -0.10-(-0.01), P=0.019] as a weakly negative predictor of LOS. Upon simple logistic regression, the odds ratio for 90-day revision was 1.81 (95% CI 1.02-3.19, P=0.042) for every unit increase in HbA1c. Patients with mean PG ≥165 mg/dL [OR=5.76 (95% CI 1.28-26.01), P=0.024] were at increased risk for 90-day revision. Glycemic laboratory values do not seem to predict 90-day wound complications or 90-day readmission following surgery for ASD. Elevated preoperative HbA1c is associated with increased LOS and risk for revision within 90 days of ASD surgery. Postoperative hyperglycemia is also associated with increased 90-day revision risk. To our knowledge, this study is the first to evaluate HbA1c and outcomes following ASD surgery. These findings can be leveraged to inform preoperative medical optimization and highlight the importance of glycemic control in ASD patients undergoing corrective surgical intervention.

The transient dynamic wave process in unidirectional composites

The propagation of nonstationary waves in unidirectional composite material is simulated by finite-element analysis. The composite material is explicitly formulated, i.e., discrete, stiff, elastic inclusions uniformly distributed in a viscoelastic matrix are modeled. An original procedure rooted in the linear Boltzmann–Volterra equations accounts for the viscoelastic effects in the matrix behavior. The chosen approach involves finite-element simulations of the transient wave process in two indicative configurations to study the effects attributed to wave scattering by the inclusions. The transient wave propagation in the unidirectional composite material and a viscoelastic specimen without inclusions are compared. Peculiarities in the numerical results due to the finite-element algorithm employed are decoupled from the output that reveals purely mechanical phenomena. For this purpose, the transient wave propagation in a one-dimensional elastic continuum, for which the exact analytical solution is well known, is effectively obtained by finite-element analysis. Furthermore, based on the unidirectional composite a homogenized model is defined by applying the mixture rule. An additional comparison between the composite containing discrete inclusions and the analogous homogenized material provides a basis to assess the output of models obtained by implementing a self-consistent scheme in a broader context.

An Integrated Artificial Intelligence Approach for Building Energy Demand Forecasting

Buildings are complex assets, characterized by environments and uses that change over time, variable occupancies, and long life cycles. They have high operational costs, mostly due to their energy requirements, and account for 30% to 40% of global greenhouse gas emissions. Consequently, substantial effort has been made to forecast their energy needs, with the scope of optimizing their economic and environmental impact. In this regard, the available literature focuses mainly on short-term modeling through the implementation of sets of physics-based equations (i.e., white-box), functional relationships between input and output variables (i.e., black-box), or a combination of both (i.e., grey-box). On the other hand, more research is required on long-term forecast models with the aim of reducing the energy needs. Within this context, this article presents an original automatic procedure for forecasting the energy needs of buildings in short- and long-term time horizons. This is accomplished by scaling an unknown facility from a similar facility that is already known and by executing a black-box approach based on machine learning algorithms. The proposed method is implemented in real case studies in Italy, predicting the energy needs (i.e., heating, cooling, and electricity) of Sant’Anna Hospital in Ferrara using the historical data of Ca’ Foncello Hospital in Treviso. The results show an adjusted coefficient of determination above 0.7 and an average error below 10% for all the energy vectors, demonstrating a feasible forecast performance with a low training set-to-test set ratio.

High-throughput LC-PDA method for determination of Δ9-THC and related cannabinoids in Cannabis sativa

Before the passage of the Agriculture Improvement Act of 2018, more commonly referred to as the 2018 Farm Bill, forensic laboratories were only required to perform qualitative measurements to confirm the identity of seized plant samples as Cannabis sativa (hemp or marijuana). The new law defines hemp at a federal level as Cannabis sativa containing 0.3 % or less Δ9-THC. Because forensic laboratories were not adequately equipped with the proper methods or training to meet these requirements, significant backlogs in casework resulted. The National Institute of Standards and Technology (NIST) responded by providing analytical tools to the forensic community. An accurate and precise method was previously developed to determine Δ9-THC, Δ9-THCA, and total Δ9-THC in botanical samples based on liquid chromatography with photodiode array detection (LC-PDA). Cannabis plant samples were ground and extracted with methanol using routine laboratory equipment. The original sample preparation procedure was time-consuming, taking over 70 min. The method described here has been optimized with the time required for sample preparation and LC-PDA analysis has been reduced to less than 30 min.

Scheduling as a Constraint Satisfaction Problem (Using the Example of Open-Pit Minе Production Scheduling Problem)

The research described in the work is aimed at developing methods for Scheduling. The fundamental disadvantage of the existing methods of Mixed-Integer Linear Programming in application to the problems under consideration is the fact that they are too demanding on the amount of RAM. The difficulty of applying local search procedures to such high-dimensional problems is to develop an effective way to find an acceptable initial approximation and determine the neighboring state transition function, which would allow achieving the optimum fast enough. In the Operations Research Theory, adding additional conditions to a problem can lead to a fundamental change in the problem-solving scheme. The methods proposed in the study are implemented within the framework of the Constraint Programming Paradigm which makes it possible to represent the subject domain dependencies saving RAM, as well as to provide the ability to step-by-step take into account heterogeneous problem conditions without essentially changing the scheme of finding solutions. A significant part of the research deals with methods of logical inference on constraints to reduce the search space and speed up the computational process. The approach to scheduling is illustrated by the Open-Pit Mine Production Scheduling Problem, which was first proposed to be solved as a Constraint Satisfaction Problem. In order to find the first feasible solution, a «greedy» search method is proposed, the result of which can be improved using the developed hybrid method. Both methods rely on original procedures of inference on constraints. The proposed approach has proven its efficiency for block models with sizes of tens and hundreds of thousands of blocks.

Application of the 5th WHO Guidelines for the Diagnosis of Lung Carcinoma in Small Lung Biopsies in a Tertiary Care Center: Is Insecurity of Pathologists for the Accurate Diagnosis Justified?

The diagnosis of lung carcinoma (LC) is currently performed in small biopsies and according to the WHO classification by using limited stains to spare tissue for molecular testing. This procedure, however, often causes diagnostic uncertainty among pathologists. In this retrospective analysis, we compared the diagnosis made by these guidelines in 288 lung biopsies with that using more stains, as retrieved from our archive. We also compared the results of p63 and p40 immunoexpression and investigated the diagnostic role of p53/Rb1. In our investigation, we reached a definite diagnosis with a mean number of one stain compared with six stains in the original diagnostic procedure, with a 97.3% concordance rate. Only in the case of metastases, a clear advantage is proven in the use of more stains, especially in the absence of clinical information. We also found a comparable utility of p40 and p63 for the diagnosis of squamous cell carcinoma, despite the higher p63 expression in other histological types. Moreover, normal p53/Rb1 expression could be utilized for the exclusion of small-cell LC. Our study confirms the diagnostic certainty achieved by the suggestions of the WHO classification and justifies the potential insecurity in the absence of adequate communication with the treating clinician.

Determination of ammonium and nitrate in soils by digital colorimetry.

A method of digital colorimetric determination of ammonium and nitrate in soils is proposed. The method is based on corresponding photometric procedures of ammonium and nitrate determination after potassium chloride extraction from soil samples. Ammonium is determined as an indophenol dye, and nitrate is determined as an azo dye. The original procedures were modified to overcome the lower sensitivity of the digital colorimetric method. For ammonium determination, the time required for the reaction to proceed completely was studied. Along with the use of a 96-well microplate protected from ambient light by a special frame, mathematical correction of scattered radiation using black ink and taking the images by a scanner in transmission mode without any post-processing, the resulting colorimetric methods proved to provide accuracy and sensitivity close to those of the spectrophotometric method, and the overall analysis speed for tens of samples was even higher. Limits of detection and quantitation for NO3- were 0.42 and 1.4mg/kg, and for NH4+, they were 1.1 and 3.7mg/kg, which is lower than for standard methods. The methods' validity was proven by the analysis of standard samples and by the analysis of soil samples collected in several districts of the Moscow region.

Milestones in Surgical Complication Reporting: Clavien-Dindo Classification 20 Years and Comprehensive Complication Index 10 Years.

To provide improved guidance for the consistent application of the Clavien-Dindo classification (CDC) and Comprehensive Complication Index (CCI ® ) in challenging clinical scenarios. Standardized outcome reporting is key for the proper assessment of surgical procedures. A recent consensus conference recommended the CDC and the CCI ® for assessing postoperative morbidity. Several challenging scenarios for grading complications still require evidence-based guidance, and the use of the 2 metrics in randomized controlled trials (RCTs) remains unexplored. We assessed the use of the CDC and CCI ® as an outcome measure in a systematic literature search. In addition, we asked 163 international surgeons to critically evaluate and independently grade complications in 20 complex clinical scenarios. Finally, a Core Group of 5 experts used this information to develop consistent recommendations. Until July 2023, 1327 RCTs selected the CDC and/or CCI ® to assess morbidity. Annual use was steadily increasing with now over 200 new RCTs per year. However, only a third (n = 335) of published RCTs provided the complete range of CDC grades, including all subgrades. Eighty-nine out of 163 surgeons (response rate: 55%) completed the questionnaire that served as a basis for the recommendations: repetitive interventions that are required to treat one complication, complications followed by further complications, complications occurring before referral, and expected and unrelated complications to the original procedure should all be counted separately and included in the CCI ® . Invasive blank diagnostic interventions should not be considered a complication. The increasing use of the CDC and CCI ® in RCTs highlights the importance of their standardized application. The current consensus on various difficult scenarios may offer novel guidance for the consistent use of the CDC and CCI ® , aiming to improve complication reporting and better quality control, ultimately benefiting all health care stakeholders and, first and foremost, all patients.

Fe3O4@ZnO Core-Shell Nanoparticles—a novel facile fabricated magnetically separable photocatalyst

The current study proposes a simple and inexpensive technique to synthesise core–shell Fe3O4@ZnO as a promising photocatalyst. An easily scalable original procedure was developed based on sequential and simultaneous addition of Zn2+ and OH– ions to Fe3O4 cores, and preheating and subsequent heating of the reaction medium. The structure of Fe3O4@ZnO core–shell nanoparticles was found to be a sequence of layers including magnetite (Fe3O4), maghemite (γ-Fe2O3), goethite (α-FeOOH), and zinc oxide (ZnO) in (0001) orientation. This layer sequence ensures a smooth transition from the Fe3O4 of the core to the ZnO shell. The synthesis conditions affect layer density and thickness, which can be easily used in adjusting Fe3O4@ZnO properties.Photocatalytic degradation of a model persistent dye (naphthol green B) in the presence of Fe3O4@ZnO nanoparticles reached promising 77 % in 60 min under UV radiation, while Fe3O4 cores showed only 20 %. The wide-gap ZnO layer on the surface of the narrow-gap Fe3O4 provides charge separation and suppresses electron-hole recombination, which drastically increases photocatalytic activity of the material. Separation of the photocatalyst with a magnet showed the same result as that with a centrifuge. All of these findings lead to inexpensive fabrication, effective performance, low toxicity and simple separation of Fe3O4@ZnO.

Assessing Intra-Bundle Impregnation in Partially Impregnated Glass Fiber-Reinforced Polypropylene Composites Using a 2D Extended-Field and Multimodal Imaging Approach.

This study evaluates multimodal imaging for characterizing microstructures in partially impregnated thermoplastic matrix composites made of woven glass fiber and polypropylene. The research quantifies the impregnation degree of fiber bundles within composite plates manufactured through a simplified compression resin transfer molding process. For comparison, a reference plate was produced using compression molding of film stacks. An original surface polishing procedure was introduced to minimize surface defects while polishing partially impregnated samples. Extended-field 2D imaging techniques, including polarized light, fluorescence, and scanning electron microscopies, were used to generate images of the same microstructure at fiber-scale resolutions throughout the plate. Post-processing workflows at the macro-scale involved stitching, rigid registration, and pixel classification of FM and SEM images. Meso-scale workflows focused on 0°-oriented fiber bundles extracted from extended-field images to conduct quantitative analyses of glass fiber and porosity area fractions. A one-way ANOVA analysis confirmed the reliability of the statistical data within the 95% confidence interval. Porosity quantification based on the conducted multimodal approach indicated the sensitivity of the impregnation degree according to the layer distance from the pool of melted polypropylene in the context of simplified-CRTM. The findings underscore the potential of multimodal imaging for quantitative analysis in composite material production.

Computational assessment of Amazon forest plots regrowth capacity under strong spatial variability for simulating logging scenarios

In this paper, we assess the regrowth capacity of tropical forest plots by developing an original computational procedure based on statistical model checking methods. We calibrate a new mathematical model of forest dynamics with respect to post-logging data, produced in the Amazon basin. Our mathematical model is determined by a mechanistic system of ordinary differential equations and integrates a new nonlinear aging term, which is necessary to reproduce the complex post-logging dynamics of the tropical forest plots. Our method is based on an efficient algorithmic procedure that explores the parameter space of the model and computes a score for each parameter value, depending on the distance between the trajectory of the model and the data. We distinguish a group of four reference plots, for which the logging was the most intense, from another group of five non-reference plots, which are fitted a posteriori. Our results provide a set trajectories of the new model, which successfully fit the non-monotone post-logging data on each forest plot, in spite of the high level of biological variability identified in the study site. Rather than a unique set of parameters, we return a small cell of parameters, extracted from the parameter space, which contains in its close vicinity several relevant sets of parameters that are equally able to reproduce the regrowth dynamics of distinct tropical forest plots. The size of the cells that should be extracted from the parameter space increases with the level of biological variability. Finally, we show how to use the calibrated mathematical model for simulating logging scenarios, so as to better understand the temporal dynamics of forest regrowth.

Intraoperative Pathology Consultation in Patients With p16-Positive Unknown Primary Squamous Cell Carcinoma

Current guidelines recommend intraoperative frozen section(s) during diagnostic surgery for squamous cell carcinoma for unknown primary tumors (SCCUP). To determine the utility of intraoperative pathology consultation during transoral robotic surgery (TORS) in localizing primary tumors and influencing need for adjuvant therapy. A retrospective case series including 47 adult patients with human papillomavirus (HPV)-associated SCCUP who underwent TORS/oropharyngectomy between January 2016 and February 2023 was carried out at a single tertiary care hospital. The analysis took place on May 13, 2024. Nodal stage, tonsillectomy history, extranodal extension (ENE). Intraoperative pathology consultation and final pathology results were compared with surgical outcomes, including margin revision, need for second procedure and/or radiation with or without chemotherapy. This study included 47 adult patients. Mean (range) age was 61 (41-79) years; patients were mostly men (37 [79%]). Overall, primary tumors were identified in 37 patients (79%), including all cases with positive nodes involving more than 1 neck level. Patients whose primary tumor was not found tended to have tobacco use history (8/10 vs 13/37 [35%]; difference, 45%; 95% CI, 16%-74%) and absence of ENE (8/10 vs 15/37 [41%]; difference, 39%; 95% CI, 10%-68%). Primary tumor was identified intraoperatively in 18 of 37 patients (49%). SCCs identified intraoperatively were significantly larger than SCCs found on permanent sections only: mean (SE), 1.2 (0.13) cm vs 0.5 (0.1) cm (difference, 0.7 cm; 95% CI, 0.53-1.94). The sensitivity, specificity, positive predictive value, and negative predictive value of intraoperative consultation was 49% (95% CI, 33%-64%), 100% (95% CI, 100%-100%), 100%, and 34% (95% CI, 19%-53%), respectively. Margins were revised in 11 of 18 patients (61%) whose primary tumor was identified intraoperatively (during original procedure) and in 3 of 19 patients (16%) whose primary tumor was identified on permanent pathologic findings only (during a second procedure) (11/18 [61%] vs 3/19 [16%]; difference, 45%; 95% CI, 17%-73%). However, there was no significant difference in the use of adjuvant radiotherapy with or without chemotherapy or need for a second procedure based on intraoperative primary tumor localization. In this case series study, the sensitivity and negative predictive value of intraoperative pathology consultation among 47 patients was less than 50%. Given the lack of influence on the need for radiotherapy with or without chemotherapy or second procedure, the practical utility of routine intraoperative frozen section requires further scrutiny.

Location Is Everything: Influence of His-Tag Fusion Site on Properties of Adenylosuccinate Synthetase from Helicobacter pylori.

The requirement for fast and dependable protein purification methods is constant, either for functional studies of natural proteins or for the production of biotechnological protein products. The original procedure has to be formulated for each individual protein, and this demanding task was significantly simplified by the introduction of affinity tags. Helicobacter pylori adenylosuccinate synthetase (AdSS) is present in solution in a dynamic equilibrium of monomers and biologically active homodimers. The addition of the His6-tag on the C-terminus (C-His-AdSS) was proven to have a negligible effect on the characteristics of this enzyme. This paper shows that the same enzyme with the His6-tag fused on its N-terminus (N-His-AdSS) has a high tendency to precipitate. Circular dichroism and X-ray diffraction studies do not detect any structural change that could explain this propensity. However, the dynamic light scattering, differential scanning fluorimetry, and analytical ultracentrifugation measurements indicate that the monomer of this construct is prone to aggregation, which shifts the equilibrium towards the insoluble precipitant. In agreement, enzyme kinetics measurements showed reduced enzyme activity, but preserved affinity for the substrates, in comparison with the wild-type and C-His-AdSS. The presented results reinforce the notion that testing the influence of the tag on protein properties should not be overlooked.

Temperature rising and anti-freezing performance of gravel-clay mixed with PCM applying infrared radiation during winter construction

Freeze–thaw cycles could easily cause the structural damage and mechanic performance deterioration of clay. In order to prevent the freeze–thaw cycles problem in the core-wall zone of the high core-wall rock-fill dam in cold regions, gravel-clay mixed with phase change material (GC-PCM) can be used as damming material and present a certain level of anti-freezing performance during winter construction. However, GC-PCM construction work area is still likely to run a risk of freezing under the severe cold and strong wind weather. In order to solve the freezing problem of GC-PCM, this study developed an infrared radiant heating device without interfering with the original construction procedure and conducted an indoor test to investigate the temperature rising performance of GC-PCM after receiving infrared radiation. Also, a numerical simulation method was proposed for the temperature rising and anti-freezing performance of the GC-PCM construction work area and the effects of different factors (including radiant pass, moving speed of infrared device and wind speed) on the anti-freezing performance were analysed subsequently. Main results show that: (1) the effectiveness of proposed numerical simulation method is validated by the indoor test; (2) after receiving 8-pass infrared radiation, the GC-PCM construction work area at 4 % PCM content remains unfrozen in 24 hours under the typical weather in December; and (3) instead of increasing radiant passes, reducing the moving speed of infrared device can better improve the anti-freezing performance of GC-PCM. This study validates the feasibility of applying infrared radiant heating method on GC-PCM, providing a potential technical means for gravel-clay anti-freezing during winter construction.

Improvement in Quality of Life after Laparoscopic or Robotic-assisted Sacrocolpopexy with a Single Anterior Mesh in Patients with Pelvic Organ Prolapse: A Retrospective Analysis from a Single Institution.

Pelvic organ prolapse (POP) is a significant health-care problem for older women. We have treated POP surgically using laparoscopic sacrocolpopexy (LSC) or robotic-assisted sacrocolpopexy (RSC). The original LSC and RSC procedures were done with anterior and posterior meshes; however, the use of the single mesh procedure is increasing because of its simplicity and safety. There have been few reports about the change in quality of life (QOL) using the single mesh procedure. Therefore, the present study aimed to retrospectively evaluate the change in QOL by LSC and RSC using a single anterior mesh for women without posterior compartment prolapse. We performed LSC or RSC using a single anterior mesh in 52 patients who had POP without posterior vaginal wall prolapse between August 2018 and October 2022. We assessed the QOL before and after surgery using prolapse-QOL (P-QOL) questionnaires. All patients who received LSC or RSC with a single anterior mesh left the hospital as scheduled without severe perioperative complications. There were no instances of wound infection or vaginal mesh extrusion. The recovery rate of questionnaires was 63.5% (33/52). All QOL score domains improved significantly, and there were no questionnaire parameters that worsened. LSC or RSC using only a single anterior mesh improves P-QOL with a low incidence of surgical complications for POP patients who did not have posterior vaginal wall prolapse. LSC or RSC with a single anterior mesh may be a prospective new procedure for POP.

Automated analysis for glaucoma screening of retinal videos acquired with smartphone-based ophthalmoscope

Widespread screening is crucial for the early diagnosis and treatment of glaucoma, the leading cause of visual impairment and blindness. The development of portable technologies, such as smartphone-based ophthalmoscopes, able to image the optical nerve head, represents a resource for large-scale glaucoma screening. Indeed, they consist of an optical device attached to a common smartphone, making the overall device cheap and easy to use. Automated analyses able to assist clinicians are crucial for fast, reproducible, and accurate screening, and can promote its diffusion making it possible even for non-expert ophthalmologists. Images acquired with smartphone ophthalmoscopes differ from that acquired with a fundus camera for the field of view, noise, colour, and the presence of pupil, iris and eyelid. Consequently, algorithms specifically designed for this type of image need to be developed.We propose a completely automated analysis of retinal video acquired with smartphone ophthalmoscopy. The proposed algorithm, based on convolutional neural networks, selects the most relevant frames in the video, segments both optic disc and cup, and computes the cup-to-disc ratio. The developed networks were partially trained on images from a publicly available fundus camera datasets, modified through an original procedure to be statistically equal to the ones acquired with a smartphone ophthalmoscope. The proposed algorithm achieves good results in images acquired from healthy and pathological subjects. Indeed, an accuracy ≥95 % was obtained for both disc and cup segmentation and the computed cup-to-disc ratios denote good agreement with manual analysis (mean difference 9 %), allowing a substantial differentiation between healthy and pathological subjects.

Safety assessment of masonry undamaged and damaged arches subjected to gravitational loads and horizontal forces. A numeric procedure to identify the optimal thrust line

In 2019 the authors formulated a numerical procedure for assessing the safety of masonry arches based on their geometry and the shape of the thrust line. The thrust line is calculated to be nearest to the geometric axis of the arch, because it is that corresponding to the optimal inner stress state. The original procedure, which focused on the safety analysis of undamaged fixed arches subject to gravitational loads, is reformulated here to also consider arches on pinned supports as well as damaged arches, i.e. one- and two-hinged arches. The procedure is further extended to also assess safety against horizontal actions, such as those resulting from an earthquake. Finally, safety is evaluated by identifying the domain of admissible thrust lines within the thickness of the arch and by computing the degree of safety in terms of the capacity of the thrust line to be moved vertically within the domain. The reformulation and extension of the procedure exploits the technique of partitioned matrices to enable automation and easy implementation in structural calculation software.

An Institutional Analysis of Early Postoperative Free Tissue Transfer Takeback Procedures.

Postoperative free tissue transfer reexploration procedures are relatively infrequent but associated with increased overall failure rates. This study examines the differences between flaps requiring takeback versus no takeback, as well as trends in reexploration techniques that may increase the odds of successful salvage. A retrospective review was conducted on all free tissue transfers performed at our institution from 2011 to 2022. Patients who underwent flap reexploration within 30 days of the original procedure were compared with a randomly selected control group who underwent free flap procedures without reexploration (1:2 cases to controls). Univariate and multivariate logistic regression analyses were performed. From 1,213 free tissue transfers performed in the study period, 187 patients were included in the analysis. Of the total flaps performed, 62 (0.05%) required takeback, and 125 were randomly selected as a control group. Free flap indication, flap type, reconstruction location, and number of venous anastomoses differed significantly between the two groups. Among the reexplored flaps, 8 (4.3% of the total) had a subsequent failure while 54 (87.10%) were salvaged, with significant differences in cause of initial flap failure, affected vessel type, and salvage technique. Free tissue transfers least prone to reexploration involved breast reconstruction in patients without predisposition to hypercoagulability or reconstruction history. When takeback operations were required, salvage was more likely in those without microvascular compromise or with an isolated venous injury who required a single exploratory operation.