bluuebunny/crossref_metadata_2025 huggingface dataset:
Shape restricted additive hazards models: Monotone, unimodal, and U‐shape hazard functions
Authors: Chung Yunro , Ivanova Anastasia , Fine Jason P.
Published: February 2024

We consider estimation of the semiparametric additive hazards model with an unspecified baseline hazard function where the effect of a continuous covariate has a specific shape but otherwise unspecified. Such estimation is particularly useful for a unimodal hazard function, where the hazard is monotone increasing and monotone decreasing with an unknown mode. A popular approach of the proportional hazards model is limited in such setting due to the complicated structure of the partial likelihood. Our model defines a quadratic loss function, and its simple structure allows a global Hessian matrix that does not involve parameters. Thus, once the global Hessian matrix is computed, a standard quadratic programming method can be applicable by profiling all possible locations of the mode. However, the quadratic programming method may be inefficient to handle a large global Hessian matrix in the profiling algorithm due to a large dimensionality, where the dimension of the global Hessian matrix and number of hypothetical modes are the same order as the sample size. We propose the quadratic pool adjacent violators algorithm to reduce computational costs. The proposed algorithm is extended to the model with a time‐dependent covariate with monotone or U‐shape hazard function. In simulation studies, our proposed method improves computational speed compared to the quadratic programming method, with bias and mean square error reductions. We analyze data from a recent cardiovascular study.
Designing of target‐specific N‐substituted tetrahydroquinoline derivatives as potent mTOR inhibitors via integrated structure‐guided computational approaches
Authors: Shaw Suman , Dey Rajdeep , Bhatt Hardik , Patel Bhumika , Patel Saumya , Dixit Nandan , Chaube Udit
Published: February 2024

There is a need to develop innovative, safe, and more effective treatment methods for lung cancer due to obstacles including resistance, side effects, and low bioavailability, among others related to present medicines. Our previous research findings gave some promising results of tetrahydroquinoline (THQ) derivatives as mTOR inhibitors for the treatment of lung cancer. The current research has employed certain integrated computational techniques to enhance the effectiveness of THQ derivatives. Various computational methods, like the generation of the pharmacophore model, virtual screening, and QSAR modeling were employed to achieve the goal, and their results were connected to develop novel THQ analogues. This study revealed that among 48 newly designed THQ derivatives, the compound UC_1 indicated the XP Gscore of −9.378 kcal/mol and also showed the key amino acid interactions with the mTOR protein viz. Gln2167, Val2240. Interestingly, compound UC_1 showed a better binding affinity with the mTOR protein compared to the clinical trial molecules viz. AZD‐8055 and AZD‐2014. The molecular dynamics simulations (100 ns) along with each output give a shred of strong evidence that the designed THQ derivative (UC_1) has all the required features in terms of inhibiting mTOR protein for the treatment of lung cancer.
iSKIN: Integrated application of machine learning and Mondrian conformal prediction to detect skin sensitizers in cosmetic raw materials
Authors: Kong Weikaixin , Zhu Jie , Shan Peipei , Ying Huiyan , Chen Tongyu , Zhang Bowen , Peng Chao , Wang Zihan , Wang Yifan , Huang Liting , Bi Suzhen , Ma Weining , Huang Zhuo , Zhu Sujie , Liu Xueyan , Li Chun
Published: February 2024

Animal experiments traditionally identify sensitizers in cosmetic materials. However, with growing concerns over animal ethics and bans on such experiments globally, alternative methods like machine learning are gaining prominence for their efficiency and cost‐effectiveness. In this study, to develop a robust sensitizer detector model, we first constructed benchmark data sets using data from previous studies and a public database, then 589 sensitizers and 831 nonsensitizers were collected. In addition, a graph‐based autoencoder and Mondrian conformal prediction (MCP) were combined to build a robust sensitizer detector, iSKIN. In the independent test set, the Matthews correlation coefficient (MCC) and the area under the receiver operating characteristic curve (ROCAUC) values of the iSKIN model without MCP were 0.472 and 0.804, respectively, which are higher than those of the three baseline models. When setting the significance level in MCP at 0.7, the MCC and ROCAUC values of iSKIN could achieve 0.753 and 0.927, respectively. Regrouping experiments proved that the MCP method is robust in the improvement of model performance. Through key structure analysis, seven key substructures in sensitizers were identified to guide cosmetic material design. Notably, long chains with halogen atoms and phenyl groups with two chlorine atoms at ortho‐positions were potential sensitizers. Finally, a user‐friendly web tool (http://www.iskin.work/) of the iSKIN model was deployed to be used by other researchers. In summary, the proposed iSKIN model has achieved state‐of‐the‐art performance so far, which can contribute to the safety evaluation of cosmetic raw materials and provide a reference for the chemical structure design of these materials.
Tarsis: An effective automata‐based abstract domain for string analysis
Authors: Negrini Luca , Arceri Vincenzo , Cortesi Agostino , Ferrara Pietro
Published: February 2024

In this paper, we introduce Tarsis, a new abstract domain based on the abstract interpretation theory that approximates string values through finite state automata. The main novelty of Tarsis is that it works over an alphabet of strings instead of single characters. On the one hand, such an approach requires a more complex and refined definition of the lattice operators and of the abstract semantics of string operators. On the other hand, it is in position to obtain strictly more precise results than state‐of‐the‐art approaches. We compare Tarsis both with simpler domains and with the standard automata model, targeting case studies containing standard yet challenging string manipulations. The performance gain w.r.t. the standard automata model is also assessed, measuring the speed‐up gained by Tarsis. Experiments confirm that Tarsis can obtain precise results without incurring in excessive computational costs.
Van der Waals Heterostructures for Photoelectric, Memory, and Neural Network Applications
Authors: Xu Hang , Xue Yue , Liu Zhenqi , Tang Qing , Wang Tianyi , Gao Xichan , Qi Yaping , Chen Yong P. , Ma Chunlan , Jiang Yucheng
Published: February 2024

A van der Waals (vdW) heterostructure is formed by combining multiple materials through vdW bonds. It can combine the advantages of electronic, optical, thermal, and magnetic properties of different 2D materials and has the potential to develop into the next generation of high‐performance functional devices. Herein, the current research advances of vdW heterostructures are reviewed. First, current fabrication methods and physical structures of vdW heterostructures are summarized. The 2D/nD (n = 0,1,2,3) mixed‐dimensional heterostructures are discussed in detail. Second, a new type of vdW heterostructure is introduced based on two‐dimensional electron gas with a nanoscale junction interface. Finally, the application prospects of vdW heterostructures in photoelectric and memory devices are further outlined by combing new applications in the neural networks. This review shows that vdW heterostructures have great advantages in high integration, energy harvesting, and logical operations, and it provides directions and suggestions for the future research and application of environmentally friendly, high‐performance, and smart functional devices.
Enhancing Natural Rubber Composites with Spent Coffee Ground: Physical Properties, Odor Absorption, and Processing
Authors: Somdee Patcharapon , Prasoetsopha Natkrita , Detsunhnoen Saksan , Matnok Suchat , Ansari Manauwar Ali
Published: February 2024

This research aims to enhance natural rubber (NR) properties by incorporating spent coffee grounds (SCGs). Scanning electron microscope (SEM) reveals well‐dispersed SCG particles in the NR matrix without interaction. Shore A hardness notably increases by up to 49.90 (19% higher than unmodified), but tensile and tear strength decline with higher SCG levels. Optimal tear strength occurs at 10 phr of SCG due to uniform dispersion. The 300% modulus remains unchanged. The odor of composites (CO2 absorption) sees a 69.2% increase at 25 phr, while odor absorption efficiency peaks at 2%. Additionally, unmodified SCG affects scorch time (2.12%–23.40% increase from 1 to 20 phr) and cure time (3.12% to 76.82% improvement from 1 to 20 phr). These findings showcase improved hardness, enhanced CO2 absorption capacity, and effective odor control. Additionally, this study sheds light on the influence of SCG on processing times, contributing valuable insights for eco‐friendly applications.
RETRACTED: Development of the ARDS‐derived gene panel for lung adenocarcinoma prognosis stratification and experiment validation of CCL20 expression
Authors: Fang Jingjing , Shi Chaolu , Huang Qin , Huang Lei , Wang Xinnian , Yan Biqing
Published: February 2024

Acute respiratory distress syndrome (ARDS) is a life‐threatening condition characterized by lung inflammation and high mortality rates. Lung cancer, specifically lung adenocarcinoma (LUAD), is a major cause of cancer‐related deaths worldwide. Patients with LUAD, particularly those undergoing chemotherapy, are more likely to develop ARDS. ARDS inflicts major malfunctioning in the immune system. We suspected a certain shared pathogenic mechanism between these diseases. This study analyzed 503 LUAD patients from the TCGA‐LUAD cohort as the training set, 85 LUAD cases from the GSE30219 cohort as the validation set, and 24 RNA‐seq samples from ARDS mice model and control groups in the GSE2411 cohort. The differentially expressed genes (DEGs) of ARDS were analyzed using the limma package and screened by Cox and Lasso analysis. ssGSEA and xCell algorithms were utilized for immune landscaping. RT‐qPCR analysis was used to determine the mRNA levels of key genes in both the LPS‐induced ARDS model and human LUAD cell lines. We identified DEGs between ARDS and control groups, which were highly associated with cytokine production and leukocyte migration. A prognosis model for LUAD patients was developed based on the expressions of the key genes in the ARDS‐derived DEGs, including FMO3, IL1R2, CCL20, CFTR, and GADD45G. A satisfactory efficacy was observed in both the training and validation cohorts. The model demonstrated increased effectiveness in predicting the intratumor immune profile and mutation status of LUAD. Moreover, we utilized LPS to induce the ARDS model, which resulted in elevated expressions of IL1R2 and CCL20. Additionally, CCL20 was upregulated in cancerous LUAD cell lines. We developed an ARDS‐based model for stratifying LUAD prognosis. CCL20 was found to be elevated in both the ARDS model and LUAD, suggesting a shared underlying mechanism of these two diseases.
Three Strategies for Supporting Elementary Writers through the Practice of Sharing
Authors: Lewis Bethany P.
Published: February 2024

Although orally sharing and discussing written compositions has been shown to benefit elementary students, it can be challenging to entwine this additional pedagogy with an already full literacy instructional period. This article acknowledges these challenges and outlines three evidence‐based instructional modifications to encourage active sharing in literacy classrooms to support developing writers. The three strategies are (1) The “Single Share,” (2) “The Sticky and the Sticker,” and (3) “The Borrow.” The benefits of each strategy are discussed within the elementary literacy context, and insight into the successful implementation of each pedagogical approach is provided for educators.
Metagenomic analysis unravels novel taxonomic differences in the uterine microbiome between healthy mares and mares with endometritis
Authors: Virendra Aeknath , Gulavane Sarita U. , Ahmed Zulfikar A. , Reddy Ravi , Chaudhari Ravindra J. , Gaikwad Sandeep M. , Shelar Raju R. , Ingole Shailesh D. , Thorat Varsha D. , Khanam Afroza , Khan Firdous A.
Published: February 2024

Background

The application of high throughput technologies has enabled unravelling of unique differences between healthy mares and mares with endometritis at transcriptomic and proteomic levels. However, differences in the uterine microbiome are yet to be investigated.

Objectives

The present study was aimed at evaluating the differences in uterine microbiome between healthy mares and mares with endometritis.

Methods

Low‐volume lavage (LVL) samples were collected from the uterus of 30 mares classified into healthy (n = 15) and endometritis (n = 15) based on their reproductive history, intrauterine fluid accumulation, gross appearance of LVL samples, endometrial cytology and bacterial culture. The samples were subjected to 16S rRNA sequencing.

Results

Notable differences in the uterine microbiome were observed between healthy mares and mares with endometritis at various taxonomic levels. In healthy mares, the most abundant phylum, class, order and family were Firmicutes, Bacilli, Bacillales and Paenibacillaceae, respectively. In contrast, the most abundant corresponding taxonomic levels in mares with endometritis were Proteobacteria, Gammaproteobacteria, Enterobacterales and Enterobacteriaceae, respectively. At the genus level, Brevibacillus and Paenibacillus were more abundant in healthy mares, whereas Escherichia, Salmonella and Klebsiella were more abundant in mares with endometritis. In healthy mares, Brevibacillus brevis was the most abundant species, followed by Brevibacillus choshinensis and Paenibacillus sp JDR‐2. However, in mares with endometritis, Escherichia coli was the most abundant species, followed by Salmonella enterica and Klebsiella pneumoniae.

Conclusions

These results confirmed the previously reported presence of a uterine microbiome in healthy mares and helped unravel some alterations that occur in mares with endometritis. The findings can potentially help formulate new approaches to prevent or treat equine endometritis.
Antibiotic resistance and virulence profiles of Proteus mirabilis isolated from broiler chickens at abattoir in South Africa
Authors: Ramatla Tsepo , Ramaili Taole , Lekota Kgaugelo , Mileng Kealeboga , Ndou Rendani , Mphuthi Malekoba , Khasapane Ntelekwane , Syakalima Michelo , Thekisoe Oriel
Published: February 2024

Background

Proteus mirabilis has been identified as an important zoonotic pathogen, causing several illnesses such as diarrhoea, keratitis and urinary tract infections.

Objective

This study assessed the prevalence of P. mirabilis in broiler chickens, its antibiotic resistance (AR) patterns, ESBL‐producing P. mirabilis and the presence of virulence genes.

Methods

A total of 26 isolates were confirmed as P. mirabilis from 480 pooled broiler chicken faecal samples by polymerase chain reaction (PCR). The disk diffusion method was used to evaluate the antibacterial susceptibility test, while nine virulence genes and 26 AR genes were also screened by PCR.

Results

All 26 P. mirabilis isolates harboured the ireA (siderophore receptors), ptA, and zapA (proteases), ucaA, pmfA, atfA, and mrpA (fimbriae), hlyA and hpmA (haemolysins) virulence genes. The P. mirabilis isolates were resistant to ciprofloxacin (62%) and levofloxacin (54%), while 8 (30.7%) of the isolates were classified as multidrug resistant (MDR). PCR analysis identified the blaCTX‐M gene (62%), blaTEM (58%) and blaCTX‐M‐2 (38%). Further screening for AMR genes identified mcr‐1, cat1, cat2, qnrA, qnrD and mecA, 12%, 19%, 12%, 54%, 27% and 8%, respectively for P. mirabilis isolates. The prevalence of the integron integrase intI1 and intI2 genes was 43% and 4%, respectively.

Conclusions

The rise of ciprofloxacin and levofloxacin resistance, as well as MDR strains, is a public health threat that points to a challenge in the treatment of infections caused by these zoonotic bacteria. Furthermore, because ESBL‐producing P. mirabilis has the potential to spread to humans, the presence of blaCTX‐M‐producing P. mirabilis in broilers should be kept under control. This is the first study undertaken to isolate P. mirabilis from chicken faecal samples and investigate its antibiotic resistance status as well as virulence profiles in South Africa.
The prevalence of adhesion and biofilm genes in Staphylococcus aureus isolates from bovine mastitis: A comprehensive meta‐analysis
Authors: Sharifi Aram , Mahmoudi Peyman , Sobhani Keyvan
Published: February 2024

Background

Mastitis poses significant challenges to the dairy industry, resulting in economic losses and increased veterinary expenses. Staphylococcus aureus is a common cause of bovine mastitis, relying on efficient adhesion and biofilm formation for infection.

Objectives

This study aimed to employ meta‐analysis to investigate the occurrence of adhesion and biofilm genes in S. aureus associated with bovine mastitis, as documented in previous studies.

Methods

This meta‐analysis was done according to Preferred Reporting Items for Systematic Reviews and Meta‐Analyses, examined 22 eligible articles and revealed varying prevalence rates of adhesion and biofilm genes in S. aureus isolates from bovine mastitis.

Results

Among the genes, clfB showed the highest prevalence (p‐estimate = 0.905), followed by fnbA (p‐estimate = 0.689) and fnbB (p‐estimate = 0.502). The icaA and icaD genes also showed a relatively high prevalence (p‐estimate = 0.694 and 0.814, respectively). Conversely, the biofilm‐associated proteins gene had the lowest prevalence (p‐estimate = 0.043). Subgroup analyses based on mastitis types and publication years revealed no significant differences in gene prevalence. Insufficient data hindered the analysis of fib, sasG , eno and bbp genes.

Conclusion

This study provides valuable insights for managing S. aureus‐induced bovine mastitis. Additionally, larger‐scale research, particularly on less‐studied genes, is necessary to comprehend the molecular roles of adhesion and biofilm genes in S. aureus‐induced bovine mastitis.
Exploring the artistic dimensions of soils in the vadose zone
Authors: Wessolek Gerd , Toland Alexandra
Published: February 2024

The rise of industrialized agriculture, coupled with a global demographic shift toward urbanization, has marginalized every‐day connections between individuals and soils. This societal shift has led to a decline in the appreciation of and cultural identity with soils. Amid a broader movement aimed at fostering soil awareness and environmental action, many artists and designers have been instrumental in bringing soils to the cultural mainstream, figuring their esthetic, social, political, and ecological dimensions. Contemporary artists place great importance on the underlying idea of animating soils through artistic practice, often transcending the physical artifact itself to assign agency to soils and the myriad beings that occupy them. Artists harness a multitude of media to articulate human‐soil relationships. From the early environmental art movements of the 1960s and 1970s to contemporary works centered on urban and industrial brownfields, soils’ multifaceted roles in CO2 transformation, water and nutrient cycling, agriculture, and as living bodies buffering against pollution have become ground for public discourse. What could this mean for the vadose zone in terms of reflecting on material flows in porous media beyond understandings of soil physics? In this paper, we draw on over 20 years of experience in studying the portrayal of soil in various arts genres to deliberate the potential of creative thinking about and thinking with the vadose zone.
A review of battery state of charge estimation and management systems: Models and future prospective
Authors: Hussein Hossam M. , Aghmadi Ahmed , Abdelrahman Mahmoud S. , Rafin S M Sajjad Hossain , Mohammed Osama
Published: February 2024

Batteries are considered critical elements in most applications nowadays due to their power and energy density features. However, uncontrolled charging and discharging will negatively affect their functions and might result in a catastrophic failure of their applications. Hence, a battery management system (BMS) is mandated for their proper operation. One of the critical elements of any BMS is the state of charge (SoC) estimation process, which highly determines the needed action to maintain the battery's health and efficiency. Several methods were used to estimate the Lithium‐ion batteries (LIBs) SoC, depending on the LIBs model or any other suitable technique. This article provides a critical review of the existing SoC estimation approaches and the main LIB models with their pros and cons, their possibility to integrate with each other's for precise estimation results, and the applicability of these techniques in electric vehicles and utility applications with the commonly used standards and codes in these sectors. Moreover, this study will also explore a future framework for integrating digital twins (DTs) with BMSs for improved and advanced management. Based on this comprehensive review, it can be concluded that merging the model‐based estimation techniques with the data‐driven approaches with their promising development to determine the dynamic patterns inside the battery can efficiently achieve precise estimation results while reducing the complexity of these models. This integration will align also with the integration of digital twin technology to provide complete and accurate supervision for the BMSs.

This article is categorized under:

Emerging Technologies > Energy Storage

Emerging Technologies > Digitalization

Energy and Power Systems > Distributed Generation
From RNA sequencing measurements to the final results: A practical guide to navigating the choices and uncertainties of gene set analysis
Authors: Wünsch Milena , Sauer Christina , Callahan Patrick , Hinske Ludwig Christian , Boulesteix Anne‐Laure
Published: February 2024

Gene set analysis (GSA), a popular approach for analyzing high‐throughput gene expression data, aims to identify sets of related genes that show significantly enriched or depleted expression patterns between different conditions. In the last years, a multitude of methods have been developed for this task. However, clear guidance is lacking: choosing the right method is the first hurdle a researcher is confronted with. No less challenging than overcoming this so‐called method uncertainty is the procedure of preprocessing, from knowing which steps are required to selecting a corresponding approach from the plethora of valid options to create the accepted input object (data preprocessing uncertainty), with clear guidance again being scarce. Here, we provide a practical guide through all steps required to conduct GSA, beginning with a concise overview of a selection of established methods, including Gene Set Enrichment Analysis and Database for Annotation, Visualization, and Integrated Discovery (DAVID). We thereby lay a special focus on reviewing and explaining the necessary preprocessing steps for each method under consideration (e.g., the necessity of a transformation of the RNA sequencing data)—an essential aspect that is typically paid only limited attention to in both existing reviews and applications. To raise awareness of the spectrum of uncertainties, our review is accompanied by an extensive overview of the literature on valid approaches for each step and illustrative R code demonstrating the complex analysis pipelines. It ends with a discussion and recommendations to both users and developers to ensure that the results of GSA are, despite the above‐mentioned uncertainties, replicable and transparent.

This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Analysis of High Dimensional Data

Data: Types and Structure > Data Preparation and Processing

Applications of Computational Statistics > Genomics/Proteomics/Genetics
A trans‐Canadian positive deviance seminar for paraesophageal hernia surgery: Reporting national postoperative outcomes and consensus recommendations
Authors: Tankel James , Safieddine Najib , Malthaner Rick , French Danny , Johnston Brian , Finley Christian , Darling Gail , Ferri Lorenzo , Seely Andrew , Gowing Stephen
Published: February 2024

Background

The incidence of adverse events (AEs) and length of stay (LOS) varies significantly following paraesophageal hernia surgery. We performed a Canadian multicenter positive deviance (PD) seminar to review individual center and national level data and establish holistic perioperative practice recommendations.

Methods

A national virtual PD seminar was performed in October 2021. Recent best evidence focusing on AEs and LOS was presented. Subsequently, anonymized center‐level AE and LOS data collected between 01/2017 and 01/2021 from a prospective, web‐based database that tracks postoperative outcomes was presented. The top two performing centers with regards to these metrics were chosen and surgeons from these hospitals discussed elements of their treatment pathways that contributed to these outcomes. Consensus recommendations were then identified with participants independently rating their level of agreement.

Results

Twenty‐eight surgeons form 8 centers took part in the seminar across 5 Canadian provinces. Of the 680 included patients included, Clavien‐Dindo grade I and II/III/IV/V complications occurred in 121/39/12/2 patients (17.8%/5.7%/1.8%/0.3%). Respiratory complications were the most common (effusion 12/680, 1.7% and pneumonia 9/680, 1.3%). Esophageal and gastric perforation occurred in 7 and 4/680, (1.0% and 0.6% respectively). Median LOS varied significantly between institutions (1 day, range 1‐3 vs. 7 days, 3‐8, p < 0.001). A strong level of agreement was achieved for 10/12 of the consensus statements generated.

Conclusion

PD seminars provide a supportive forum for centers to review best evidence and experience and generate recommendations based on expert opinion. Further research is ongoing to determine if this approach effectively accomplishes this objective.
Conformal quantum mechanics, holomorphic factorisation, and ultra-spinning black holes
Authors: Dorey Nick , Mouland Rishi
Published: February 2024

Abstract

We study a limit in which a relativistic CFT reduces to conformal quantum mechanics, and relate the partition functions of the two theories. When the initial CFT is holographic, our limit coincides with an ultra-spinning limit in the gravity dual. We therefore propose that ultra-spinning black holes are dual to an appropriate ensemble in finite-dimensional conformal quantum mechanics. The limit is studied in detail for SCFTs in four and six dimensions. These theories have a superconformal index which can be computed by gluing together two or more blocks. Applying our limit to the index effectively isolates a single such block. Our results therefore suggest that ultra-spinning black holes play the role of blocks in the gravitational dual of holomorphic factorisation.
Optimization and improving of the production capacity of a flexible tyre painting cell
Authors: Santos Adriano A. , Pereira Filipe , Felgueiras Carlos
Published: February 2024

Optimization of industrial processes is a constant concern and a main task for many companies in several industry sectors. Based on optimized solutions, the company can decrease manufacturing costs, lead times or, more generally, increase benefit. However, when developing a new process, you must be sure that the new solution will add more value to the initial solution. This, among many others, is one of the main reasons why companies opt, in addition to experimentation, for the use of tools that allow for the virtual prototyping, simulation, and integration of complex and sophisticated processes. Experimentation requires approximation testing, searching for the ideal values of quantity, temperature, etc.; simulation provides industrial processes with test support ranging from flows to robotic systems such as the intelligent software. This simulation software allows to develop programs, add Computer Aided Design (CAD) layouts, and simulate the cycle times of the different tasks to be performed. In this paper, an experimental approach is presented with atomization and fan spray pressure as the study basis and a simulation of the robot-based handling solution used in a tyre production line. The result is an improvement of the painting process, optimisation of the amount of fluid deposited on the tyre, of the processed product, as well as of the running times of the robot.
A modified pull-through approach with a pedicled bone flap for oral and oropharyngeal cancer resection: a feasibility study
Authors: Neckel Norbert , Neckel Peter H. , Hirt Bernhard , Doll Christian , Hofmann Elena , Nahles Susanne , Heiland Max , Kreutzer Kilian , Koerdt Steffen
Published: February 2024

Purpose

Compromised swallowing, speaking, and local complications are the major disadvantages of established approaches to the posterior tongue and oropharynx. The mandibular split involves an esthetically unpleasant bipartition of the lower lip and is prone to bony non-union or sequestration. The conventional pull-through technique on the other hand lacks the secure reattachment of the lingually released soft tissues.

Methods

The feasibility of a new modified pull-through approach was tested on three anatomical specimens. CAD/CAM cutting guides were used to design a retentive bone flap to properly refixate the genioglossus and geniohyoid muscles after the procedure. The radiographic assessment and treatment planning was performed on 12 cadavers. The entire procedure was tested surgically via dissection in three of those cases. This procedure was then applied in a clinical case.

Results

Precise repositioning and dynamic compression of bony segments was possible reproducibly and without injury to adjacent structures. In all dissected cases, a median lingual foramen was found and in two cases vessels entering it could be dissected Radiologic anatomical landmarks were sufficient in all 12 cases to perform the clinical planning procedure. Clinically, the osteotomized segment demonstrated good blood supply and plateless repositioning was verified postoperatively via cone beam scan.

Conclusion

The method presented is safe and easy to perform. Individual cutting guides improve the safety and accuracy of the procedure, potentially eliminating the need for osteosynthesis. We provide the anatomical and radiologic basis for clinical evaluation of this pedicled bone flap procedure and present the clinical application of this modified pull-through approach.
Umfrage zur blutverdünnenden Therapie bei Patienten mit altersabhängiger Makuladegeneration
Authors: Weber Constance , Tedt Jezabel , Husser Oliver , Holz Frank G. , Liegl Raffael
Published: February 2024

Hintergrund

Patienten mit altersabhängiger Makuladegeneration (AMD) erhalten häufig zeitgleich systemische blutverdünnende Medikamente. Diese erhöhen bekanntermaßen das Risiko für schwere Blutungen, unter anderem auch im Rahmen der AMD, sodass es zu extensiven subretinalen Blutungen kommen kann.

Ziel der Arbeit

In dieser Studie soll untersucht werden, wie hoch der Anteil an Patienten mit AMD und blutverdünnender Therapie ist und welche blutverdünnenden Medikamente eingenommen werden.

Methoden

Diese Umfrage wurde prospektiv an der Universitäts-Augenklinik Bonn durchgeführt. Freiwillige wurden in der Netzhaut-Sprechstunde sowie der Sprechstunde für intravitreale Injektionen (IVOM) rekrutiert.

Ergebnisse

Insgesamt konnten 178 Fragebögen von 178 Patienten ausgewertet werden, bei denen der Fragebogen vollständig ausgefüllt wurde. Das Durchschnittsalter betrug 81,7 Jahre (58 bis 100); 101 Patienten (57,7 %) nahmen eine blutverdünnende Therapie ein. Die Mehrheit der Patienten nahm Thrombozytenaggregationshemmer (n = 59; 58,4 %), insbesondere ASS (n = 55; 54,5 %) ein. Direkte orale Antikoagulanzien (DOAK) wurden von 33 Patienten (32,7 %) eingenommen, darunter am häufigsten Apixaban (17,8 %). Vitamin-K-Antagonisten (VKA) wurde von 4 Patienten (4 %) eingenommen. Als häufigster Grund für eine blutverdünnende Therapie wurde ein VHF benannt (n = 32, 31,7 %), gefolgt von einer Stentimplantation (n = 20, 19,8 %) und einem Schlaganfallgeschehen (n = 12, 11,9 %); 13 Patienten (12,9 %) wussten nicht, warum sie eine blutverdünnende Therapie einnahmen. Bei 31 Patienten (30,7 %) lag eine nicht eindeutig nachvollziehbare Indikation vor.

Diskussion

In unserer Kohorte nahm ein Großteil der Patienten mit AMD eine blutverdünnende Therapie ein. Nicht bei jedem Patienten liegt jedoch eine eindeutige Indikation zur Einnahme vor. Hier sollte die Einnahme aufgrund des erhöhten Blutungsrisikos in enger Zusammenarbeit mit Hausärzten und Kardiologen kritisch hinterfragt werden.
Clinical and serological characterization of acute pleuropericarditis suggests an autoinflammatory pathogenesis and highlights risk factors for recurrent attacks
Authors: Kaudewitz Dorothee , John Lukas , Meis Jan , Frey Norbert , Lorenz Hanns-Martin , Leuschner Florian , Blank Norbert
Published: February 2024

Purpose

We describe the manifestations and course of patients with pleuropericarditis (PP). Serum parameters were analyzed to evaluate the contribution of autoimmune and autoinflammatory mechanisms to PP pathogenesis. Finally, we outline risk factors for recurrent PP attacks.

Methods

Electronic medical records of the University Hospital Heidelberg were screened for PP diagnosis between the years 2009 and 2021. A total of 164 patients were detected and compared to patients suffering from systemic lupus erythematosus (SLE)-associated PP. Follow-up data were collected until January 2023.

Results

In 57.3% of a total of 164 PP cases, no trigger was identified (idiopathic PP). The clinical manifestations were similar in subgroups with different triggers (idiopathic, post-cardiac injury and post-infectious). None of the patients in the idiopathic-PP (i-PP) group fulfilled the diagnostic criteria of an autoimmune disease and the i-PP group could be clearly discriminated by clinical, epidemiological and serological means from the control cohort of SLE-associated PP. After a median follow-up of 1048 days, the majority of PP patients (72.7%) had at least one PP relapse. Univariate analyses showed that CRP, SAA (serum amyloid A), troponin T, NT-BNP and post-cardiac injury were negatively correlated, while the presence of fever and an idiopathic trigger were positively correlated with recurrence of PP. Multivariate analyses showed that fever, an idiopathic trigger and low SAA values were risk factors for PP recurrence.

Conclusion

This study highlights that most cases of PP are idiopathic and PP cases with various triggers have an identical clinical phenotype. Our data suggest that the clinical, epidemiological and serological characteristics of idiopathic PP considerably differ from patients with PP caused by autoimmune disease like SLE. We further demonstrate that PP has a high risk of recurrence and identify factors associated with this risk, allowing for a targeted secondary prophylaxis.

Graphical Abstract
Frailty, periinterventional complications and outcome in patients undergoing percutaneous mitral and tricuspid valve repair
Authors: Schäfer Matthieu , Nöth Hannah , Metze Clemens , Iliadis Christos , Körber Maria Isabel , Halbach Marcel , Baldus Stephan , Pfister Roman
Published: February 2024

Background

Frailty is common in elderly and multimorbid patients and associated with increased vulnerability to stressors.

Methods

In a single centre study frailty according to Fried criteria was assessed in consecutive patients before transcatheter mitral and tricuspid valve repair. Postprocedural infections, blood transfusion and bleeding and renal failure were retrospectively assessed from records. Median follow-up time for survival was 560 days (IQR: 363 to 730 days).

Results

90% of 626 patients underwent mitral valve repair, 5% tricuspid valve repair, and 5% simultaneous mitral and tricuspid valve repair. 47% were classified as frail. Frailty was associated with a significantly increased frequency of bleeding (16 vs 10%; p = 0.016), blood transfusions (9 vs 3%; p =  < 0.001) and infections (18 vs 10%; p = 0.006), but not with acute kidney injury (20 vs 20%; p = 1.00). Bleeding and infections were associated with longer hospital stays, with a more pronounced effect in frail patients (interaction test p < 0.05, additional 3.2 and 4.1 days in frail patients, respectively). Adjustment for the occurrence of complications did not attenuate the increased risk of mortality associated with frailty (HR 2.24 [95% CI 1.62–3.10]; p < 0.001).

Conclusions

Bleeding complications and infections were more frequent in frail patients undergoing transcatheter mitral and tricuspid valve repair and partly explained the longer hospital stay. Albeit some of the complications were associated with higher long-term mortality, this did not explain the strong association between frailty and mortality. Further research is warranted to explore interventions targeting periprocedural complications to improve outcomes in this vulnerable population.

Graphical abstract
Comparison of Arctic Front Advance Pro and POLARx cryoballoons for ablation therapy of atrial fibrillation: an intraprocedural analysis
Authors: Knappe Vincent , Lahrmann Caroline , Funken Maximilian , Zietzer Andreas , Gestrich Christopher , Nickenig Georg , Schrickel Jan W. , Beiert Thomas
Published: February 2024

Introduction

Cryoballoon (CB) ablation has become a popular method for pulmonary vein isolation (PVI) in atrial fibrillation (AF) treatment. This study aimed to compare the intraprocedural ablation characteristics of two cryoballoons, Arctic Front Advance Pro™ (AFA-Pro, Medtronic) and POLARx™ (Boston Scientific).

Methods and results

In this retrospective single-center study, 230 symptomatic paroxysmal or persistent AF patients underwent CB ablation with either AFA-Pro or POLARx. Propensity-score matching resulted in two cohorts of 114 patients each. Baseline and procedural characteristics were comparable between both CBs. POLARx achieved lower minimal temperatures (e.g., left superior pulmonary vein, LSPV: AFA-Pro − 49.0 °C vs. POLARx − 59.5 °C) and lower temperatures at time-to-isolation (TTI). Additionally, POLARx reached lower temperatures faster, as evidenced by lower temperatures after 40 and 60 s, and a larger mean temperature change between 20 and 40 s. POLARx also had a greater area under the curve below 0 °C and a longer thawing phase. Both CBs achieved comparable high rates of final PV-isolation.

TTI, minimal esophagus temperature, and first-pass isolation rates were similar between groups. Periprocedural complications, including phrenic nerve injuries, were comparable. Troponin levels in the left atrium were elevated with both systems. Values and change in troponin were numerically higher in the POLARx group (delta troponin: AFA-Pro 36.3 (26.4, 125.4) ng/L vs. POLARx 104.9 (49.5, 122.2) ng/L), p = 0.077).

Conclusion

AFA-Pro and POLARx are both highly effective and safe CB systems for PVI. POLARx exhibited significant faster and lower freezing characteristics, and numerically higher troponin levels might indicate greater myocardial injury. However, these differences did not translate into improved performance, procedural efficiency, or safety.

Graphical abstract
Developmental characteristics of the permanent upper lateral incisor in unilateral cleft lip and palate
Authors: Knüppe Tim B. A. , Haj Mona , Strabbing Elske M. , Wolvius Eppo B. , Carvajal Monroy Paola L.
Published: February 2024

Objectives

This study aims to provide insights into the developmental characteristics of the upper lateral incisor in individuals with unilateral clefts.

Materials and methods

Panoramic radiographs of a consistent group of Caucasian children taken over time (ages 6, 9, and 12) were extensively reviewed. The study assessed the distribution pattern, eruption path, tooth development, and crown size of the upper lateral incisor within the cleft region.

Results

The most commonly observed distribution pattern was the lateral incisor located distal to the cleft, accounting for 49.2% of cases. Furthermore, a significant delay in tooth development of the upper lateral incisor on the cleft side was noted at ages 6 and 9 (p > 0.001). Compared with the non-cleft side, these incisors often erupted along the alveolar cleft and exhibited microdontia (88.3%, p < 0.041).

Conclusion

Lateral incisors on the cleft side display unique distribution patterns, microdontia, and delayed tooth development. Careful monitoring of the cuspid eruption is essential, as it can influence the eruption of the lateral incisor.

Clinical relevance

A comprehensive understanding of the development of the upper lateral incisor relative to the cleft is vital for determining its prognosis over time. The position of the upper lateral incisor can also influence the timing and prognosis of secondary alveolar bone grafting. Preserving the upper lateral incisor favors arch length, perimeter, and symmetry in individuals with unilateral clefts.
A comparison of brain retraction mechanisms using finite element analysis and the effects of regionally heterogeneous material properties
Authors: Griffiths Emma , Jayamohan Jayaratnam , Budday Silvia
Published: February 2024

Finite element (FE) simulations of the brain undergoing neurosurgical procedures present us with the great opportunity to better investigate, understand, and optimize surgical techniques and equipment. FE models provide access to data such as the stress levels within the brain that would otherwise be inaccessible with the current medical technology. Brain retraction is often a dangerous but necessary part of neurosurgery, and current research focuses on minimizing trauma during the procedure. In this work, we present a simulation-based comparison of different types of retraction mechanisms. We focus on traditional spatulas and tubular retractors. Our results show that tubular retractors result in lower average predicted stresses, especially in the subcortical structures and corpus callosum. Additionally, we show that changing the location of retraction can greatly affect the predicted stress results. As the model predictions highly depend on the material model and parameters used for simulations, we also investigate the importance of using region-specific hyperelastic and viscoelastic material parameters when modelling a three-dimensional human brain during retraction. Our investigations demonstrate how FE simulations in neurosurgical techniques can provide insight to surgeons and medical device manufacturers. They emphasize how further work into this direction could greatly improve the management and prevention of injury during surgery. Additionally, we show the importance of modelling the human brain with region-dependent parameters in order to provide useful predictions for neurosurgical procedures.
Improved honey badger algorithm based on elementary function density factors and mathematical spirals in polar coordinate systema
Authors: Zhang Si-Wen , Wang Jie-Sheng , Li Yi-Xuan , Zhang Shi-Hui , Wang Yu-Cai , Wang Xiao-Tian
Published: February 2024

The Honey Badger Algorithm (HBA) is a new swarm intelligence optimization algorithm by simulating the foraging behavior of honey badgers in nature. To further improve its convergence speed and convergence accuracy, an improved HBA based on the density factors with the elementary functions and the mathematical spirals in the polar coordinate system was proposed. The algorithm proposes six density factors for attenuation states based on elementary functions, and introduces mathematical expressions of the polar diameters and angles of seven mathematical spirals (Fibonacci spiral, Butterfly curve, Rose spiral, Cycloid, Archimedean spiral, Hypotrochoid and Cardioid) in the polar coordinate system based on the density factors with the best synthesized effect to replace the foraging strategy of honey badger digging pattern in HBA. By using 23 benchmark test functions, the above improvements are sequentially compared with the original HBA, and the optimization algorithm with the best improvement, α4CycρHBA, is selected to be compared with SOA, MVO, DOA, CDO, MFO, SCA, BA, GWO and FFA. Finally, four engineering design problems (pressure vessel design, three-bar truss design, cantilever beam design and slotted bulkhead design) were solved. The simulation experiments results show that the proposed improved HBA based on the density factors with the elementary functions and the mathematical spirals of the polar coordinate system has the characteristics of balanced exploration and expiration, fast convergence and high accuracy, and is able to solve the function optimization and engineering optimization problems in a better way.
Photon-counting CT-angiography in pre-TAVR aortic annulus assessment: effects of retrospective vs. prospective ECG-synchronization on prosthesis valve selection
Authors: Hagar Muhammad Taha , Kluemper Theresa , Hein Manuel , von Zur Muhlen Constantin , Faby Sebastian , Capilli Fabio , Schuppert Christopher , Schmitt Ramona , Ruile Philipp , Westermann Dirk , Schlett Christopher L. , Bamberg Fabian , Krauss Tobias , Soschynski Martin
Published: February 2024

To compare the diagnostic value of ultrahigh-resolution CT-angiography (UHR-CTA) compared with high-pitch spiral CTA (HPS-CTA) using a first-generation, dual-source photon-counting CT (PCD-CT) scanner for preprocedural planning of transcatheter aortic valve replacement (TAVR). Clinically referred patients with severe aortic valve stenosis underwent both, retrospective ECG-gated cardiac UHR-CTA (collimation: 120 × 0.2 mm) and prospective ECG-triggered aortoiliac HPS-CTA (collimation: 144 × 0.4 mm, full spectral capabilities) for TAVR planning from August 2022 to March 2023. Radiation dose was extracted from the CT reports, and the effective dose was calculated. Two radiologists analyzed UHR-CTA and HPS-CTA datasets, assessing the image quality of the aortic annulus, with regard to the lumen visibility and margin delineation using a 4-point visual-grading scale (ranges: 4 = ”excellent” to 1 = ”poor”). Aortic annulus area (AAA) measurements were taken for valve prosthesis sizing, with retrospective UHR-CTA serving as reference standard. A total of 64 patients were included (mean age, 81 years ± 7 SD; 28 women) in this retrospective study. HPS-CTA showed a lower radiation dose, 4.1 mSv vs. 12.6 mSv (p < 0.001). UHR-CTA demonstrated higher image quality to HPS-CTA (median score, 4 [IQR, 3–4] vs. 3 [IQR, 2–3]; p < 0.001). Quantitative assessments of AAA from both CTA datasets were strongly positively correlated (mean 477.4 ± 91.1 mm2 on UHR-CTA and mean 476.5 ± 90.4 mm2 on HPS-CTA, Pearson r2 = 0.857, p < 0.001) with a mean error of 22.3 ± 24.6 mm2 and resulted in identical valve prosthesis sizing in the majority of patients (91%). Patients with lower image quality on HPS-CTA (score value 1 or 2, n = 28) were more likely to receive different sizing recommendations (82%). Both UHR-CTA and HPS-CTA acquisitions using photon-counting CT technology provided reliable aortic annular assessments for TAVR planning. While UHR-CTA offers superior image quality, HPS-CTA is associated with lower radiation exposure. However, severely impaired image quality on HPS-CTA may impact on prosthesis sizing, suggesting that immediate post-scan image evaluations may require complementary UHR-CTA scanning.
Unique continuation problem on RCD Spaces. I
Authors: Deng Qin , Zhao Xinrui
Published: February 2024

In this note we establish the weak unique continuation theorem for caloric functions on compact RCD(K, 2) spaces and show that there exists an RCD(K, 4) space on which there exist non-trivial eigenfunctions of the Laplacian and non-stationary solutions of the heat equation which vanish up to infinite order at one point . We also establish frequency estimates for eigenfunctions and caloric functions on the metric horn. In particular, this gives a strong unique continuation type result on the metric horn for harmonic functions with a high rate of decay at the horn tip, where it is known that the standard strong unique continuation property fails.