bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrical stimulation induced structural 3D human engineered neural tissue with well-developed neuronal network and functional connectivity
Authors: Meng Xiaoting , Yu Xiyao , Lu Yingli , Pei Zhe , Wang Guoqiang , Qi Mingran , Liu Rongrong , Zhou Jiaying , Guo Xiaopin , Zhou Zhengjie , Wang Fang
Published: July 2023

Objective. Three-dimensional (3D) neural tissue engineering is expected to provide new stride in developing neural disease models and functional substitutes to aid in the treatment of central nervous system injury. We have previously detailed an electrical stimulation (ES) system to generate 3D mouse engineered neural tissue (mENT) in vitro. However, ES-induced human ENT (hENT) has not previously been either investigated or identified in structural and functional manner. Here, we applied ES as a stimulator to regulate human neural stem cells in 3D Matrigel, explored the components and functional properties of hENTs. Approach. By immunofluorescence chemical staining and electron microscope imaging, we evaluated the effects of ES on (1) neuronal differentiation and maturation, (2) neurites outgrowth and alignment in hENT, (3) formation of synapses and myelin sheaths in hENT. We further investigated the formation of synaptic connections between ex-vivo-fused mouse and human tissue. We used calcium imaging to detect activities of neurons in hENT culture. Results. ES could induce neuronal differentiation, the orderly growth of neurites and the maturation of neuron subtypes to construct a well-developed neuronal network with synapses and myelin sheaths. Most importantly, we discovered that raising extracellular K+ concentration resulted the increasing neuronal excitability in the hENT, indicating electrical activities in neuronal cells. Significance. We applied ES to generate the organised 3D hENTs and identified them in both structural and functional manner.
Flexible gear modeling and stress spectrum compilation of an artillery steering machine
Authors: Si Dongya , Fang Wenmin , Zhang Yang
Published: July 2023

To solve the load data lack problems when researching the fatigue life prediction of artillery steering machines, the flexible body model of an artillery steering gear was established using the recurdyn/fflex, based on the finite element flexible body theory. The complete artillery adjustment process of the steering gear was simulated and calculated, and the dynamic stress change of the gear under variable load conditions was obtained. Eight-level stress spectrum was compiled based on the rain flow counting method, which provides the load data basis for the subsequent reliability design and fatigue life research.
An Image Stitching Scheme Based on Cameras Coordinate Transformation and Template Matching
Authors: Wang Hua , Han Yifei , Zhang Shuang , Zhu Guokai
Published: July 2023

In the detection of a large-size longitudinal beam workpiece, it is impossible to obtain the complete picture of the workpiece only by relying on a single camera, so it is necessary to realize the position movement of the camera with the help of a motor to obtain image data one by one, in which image stitching is the key to realize this technology. Based on this, this paper proposes an image stitching scheme based on the camera’s coordinate transformation and template matching. The scheme first uses a motor to drive three cameras to the image acquisition and then uses the coordinate transformation between cameras to obtain the stitched image of the area. After cameras are moved to the next image acquisition area, the image stitching algorithm based on template matching is used to complete the image stitching of the two areas. The above steps are repeated until the cameras complete the image acquisition task of all areas and the image stitching of the final workpiece is completed. Through the experimental verification, the proposed template matching scheme for the approximate overlapping areas between images can effectively improve the efficiency of image stitching, and the specific improvement effect in this experiment can reach 46.2%, and the overall image stitching scheme meets the requirements of detection efficiency.
Analysis and Test of Indentation Rolling Resistance of Belt Conveyors
Authors: Hou Hongwei , Lan Chunsen , Feng Baozhong
Published: July 2023

The rotating resistance of conveying belt accounts for the largest proportion of the running resistance of the belt conveyor. To analyze the key factors affecting its size, a simulation analysis of the relationship between belt conveyor load, idler diameter, belt speed, and indentation rolling resistance was conducted based on the finite element method. According to the simulation content, experimental verification was carried out, and the test method of indentation rolling resistance was formed. The simulation analysis and test conclusions can provide certain technical support for the optimal design of belt conveyors.
Structural analysis of multi-way block for large-diameter pipeline connector based on ANSYS
Authors: Han Yingjie , Wu Renzhi
Published: July 2023

This paper introduces a multi-way block for large-diameter pipeline connectors designed based on Hubbed slip-on-welding steel pipe flanges, which solves the problems of complicated processing technology, poor mechanical properties, and short service life of existing welded multi-way pipe joints. The structural analysis and comparison of multi-way blocks and multi-way pipe joints under different working conditions are carried out. This paper adopts certain assumptions to simplify the model, analyzes the multi-way block and multi-way pipe joint in theory, and takes the PN16-150 multi-way block as an example to refine and verify the theoretical analysis results. In this paper, Pro-E is used to establish a three-dimensional model, and ANSYS workbench is used for structural static simulation. The simulation results show that the multi-way block has better mechanical properties than the multi-way pipe joint under the same working conditions, and the multi-way block after reducing the diameter has better mechanical properties than the equal-diameter multi-way block.
Finite element simulation of automobile crankshaft processing based on ductile iron
Authors: Zhang Chundong
Published: July 2023

Crankshaft plays a very important role as the key parts in the automobile engine. The processing of shaft parts mainly adopts the machining method of turning. The service life of the machining tool directly affects the production cost. In the machining process of shaft parts, due to its poor rigidity, it is easy to cause machining deformation, so it is of great significance to control the machining deformation of parts. In this paper, the Advantedge simulation software is used to establish the finite element model of tool wear and cutting process with nodular cast iron crankshaft parts as the research object, and the tool wear and machining deformation of shaft parts are studied respectively.
Simulation of dynamic characteristics of suspension hydraulic bushing
Authors: Zha Wenjing , Lu Chihua , Liu Zhi’en , Li Guohong , Luo Jinliang
Published: July 2023

The hydraulic bushing is a common vibration isolator, and its dynamic characteristics influence the ride comfort of the vehicle. Aiming at a suspension hydraulic bushing with inertia components, a one-dimensional model of the hydraulic bushing is established based on Amesim. Secondly, a parameter identification method is proposed, and the equivalent piston area of the hydraulic bushing and the diaphragm strain stiffness are identified by this method. Finally, the identified parameters are input into the Amesim model, and the data results are compared with the experimental results after processing with MatLab. The results show that the dynamic characteristic curve of the hydraulic bushing calculated by this method is consistent with the test curve and can well predict the dynamic characteristics of the hydraulic bushing with inertia elements.
Time-domain Reliability Estimation of Gear Train considering Failure-dependence
Authors: Bai Enjun , Yang Chaojie , Zheng Kaiming , Zhang Dongxu
Published: July 2023

A gear tooth or a gear is usually considered as an independent component in the traditional reliability research. However, gear trains are significantly different from the traditional series systems. Time-dependent configuration of the traditional series systems is fixed. But the meshing tooth-pairs of gear trains are changing all the time during operation. The failures of meshing tooth-pairs are dependent statistically under the common load action. In the paper, the reliability analysis considering time-domain meshing relation of tooth-pairs is studied and meshing relation equations are presented. Then, reliability analysis method of gear trains is developed based on the Monte Carlo simulation with dependent failure and time domain meshing relation. The differences of reliability results between time domain reliability analysis method and traditional series system reliability methods are illustrated by several examples.
Quantitative detection of crack depth in V-groove weld using laser-generated surface acoustic waves
Authors: Li Ziming
Published: July 2023

Thick-walled structures are widely used in kinds of high-end equipment. As the most conventional method adopted to manufacture large-scale structures, multi-pass butt-welds are one of the most critical areas prone to defects. In this paper, we focus on the quantitative detection of crack depth in a V-groove weld using laser-generated surface acoustic waves. A two-dimensional finite-element method with Q345 steel is adopted to reveal the complicated propagation characteristics of laser-generated surface acoustic waves with surface cracks. The displacement fields are discussed to show the wave transmission, reflection, and mode-conversion phenomena. The main propagating wave modes—P, R, R′, R′r, and R′t waved—are distinguished with the help of the out-of-plane displacement under different crack depths in the time domain. It is found that R′r can be used to locate the cracks and R′t can be used to quantify the depth of the cracks.
Study on Erosion of Small-Size At-bit Azimuthal Gamma Geosteering Tool
Authors: Sun Dongxin
Published: July 2023

Small-size at-bit azimuthal gamma geosteering tool is an important tool used in the process of old well sidetracking. It is significant to carry out numerical simulation analysis of erosion and life prediction to reduce development costs and excavate the remaining reservoir in old wells. By using the finite element software, we calculate and analyze the erosion characteristic of the drilling fluid flow and the sand content ratio of the geosteering tool. These results demonstrate that the water hole erosion rate is positively correlated to the flow rate and sand ratio respectively, and the maximal erosion rate all happens at the root of the female thread. When the drilling fluid flow rate is 14 L/s and the sand content ratio is 4%, its erosion life is about 743.2 h which satisfies the service life of downhole tools. The research results can provide theoretical guidance for configuring drilling fluid on-site, adjusting pump pressure, and prolonging the service life of tools.
Application of VMD and dynamic wavelet noise reduction techniques in rolling bearing fault diagnosis
Authors: Ma Jinghua , Li Honglei , Chen Yingchun , Wang Jingshu , Zou Zheng
Published: July 2023

This study proposes a denoising technique based on VMD and dynamic wavelet to address the difficulty of extracting rolling bearing fault vibration signal features in a noisy background. Firstly, the vibration signal is decomposed using the VMD method and the extracted IMFs are filtered. Then, dynamic wavelet are used to denoise the confused IMFs, and the IMFs are reconstructed to achieve joint denoising. Finally, a deep learning method is applied to adaptively extract the features of the noise-reduced signals for fault diagnosis. The effectiveness of the method is confirmed through experimental verification, demonstrating its ability to remove noise information from the signal and improve the presentation of fault characteristics, leading to improved accuracy in fault diagnosis.
Research on the evolutionary direction of drip irrigation irrigators based on the evolution of technological systems
Authors: Lv Bing , Ren Zekun , Shi Changyu , Wang Yuanfa
Published: July 2023

This paper introduces the theory of technical system evolution into the design of infiltration irrigation irrigators, uses patent analysis to predict the technical system of irrigators, adopts the law of dynamics suitable for the evolution of drip and infiltration irrigation irrigators, and the law of uneven evolution of subsystems to optimize the design of irrigators. It identifies the technical system evolution stage of irrigators as the growth period, forms the evolution process applicable to the growth period of irrigators, and obtains a new type of flexible integral compensated DC channel-wide flow irrigator.
The Effect of Different Degrees-of-freedom on the Vehicle Stability Control
Authors: Jiang Chengyou
Published: July 2023

As the number of vehicles in the world skyrocket over the last few decades, there have been many injuries or deaths from accidents due to all kinds of reasons. In this way, the safety, and especially stability, of vehicles now become an increasingly important research topic. At this moment, different researchers deploy different degrees of freedom (DOF) as they do the simulation studies for Vehicle Stability Control (VSC). Each has its advantages and disadvantages and affects the research in its own ways. In this paper, MATLAB and Simulink are both used to model the vehicles in different DOFs. By comparing the performance of each model, the effects of different DOFs on the VSC are analyzed, proving important ideas for the future of related research. The research concludes that VSC’s effectiveness is directly proportional to the number of DOFs. Therefore, future research needs to focus on higher DOFs to improve vehicle safety.
Upgrading Of Two Position Anti-skid Valve For Braking System Of Urban Rail Transit Vehicles
Authors: Chen Fan , Pan Yongjun
Published: July 2023

Based on the structural principle of the existing two-position anti-skid valve for urban rail vehicles, the valve has been modified to increase the pressure maintaining position based on the original only brake position and release position, so as to upgrade to the three-position anti-skid valve. As the pressure-maintaining position is added, the maximum braking force shall be kept as far as possible under the premise of anti-skid control of the train, so as to shorten the braking distance and ensure driving safety.
Virtual reference setting and its application in thermal power unit control
Authors: Zhou Hui
Published: July 2023

In thermal power units, superheater outlet temperature is a very important parameter, but because of its long delay time and large inertia, it is difficult to obtain good control effect by traditional control algorithm. In this paper, taking a supercritical once-through boiler as the research object, combined with the established superheated steam temperature object model, a two-degree-of-freedom superheater outlet temperature control system based on VRFT is designed, and compared with the conventional tuning method, it is proved that the virtual reference feedback tuning (VRFT) method has many advantages, such as simple design, less computation, no need to select initial parameters and good convergence, is an application-oriented direct control system design method.
Testing spontaneous wavefunction collapse with quantum electromechanics
Authors: Tobar Germain , Forstner Stefan , Fedorov Arkady , Bowen Warwick P
Published: July 2023

Theories of spontaneous wavefunction collapse offer an explanation of the possible breakdown of quantum mechanics for macroscopic systems. However, the challenge of resolving predicted collapse signatures above background noise has precluded conclusive tests. Here, we propose to overcome this challenge using quantum control and measurement of a superconducting qubit coupled to a macroscopic mechanical resonator. We show that this can amplify the weak signals from collapse-induced heating and simultaneously suppress qubit noise, initializing the qubit close to its ground state. Combined, this could enable a conclusive test of collapse models. The ability to quantum control macroscopic mechanical resonators and resolve extremely small signals from them could further other fundamental research beyond collapse models, such as laboratory-based dark matter searches and the reconciliation of quantum mechanics with gravity.
Techniques for combining fast local decoders with global decoders under circuit-level noise
Authors: Chamberland Christopher , Goncalves Luis , Sivarajah Prasahnt , Peterson Eric , Grimberg Sebastian
Published: July 2023

Implementing algorithms on a fault-tolerant quantum computer will require fast decoding throughput and latency times to prevent an exponential increase in buffer times between the applications of gates. In this work we begin by quantifying these requirements. We then introduce the construction of local neural network (NN) decoders using three-dimensional convolutions. These local decoders are adapted to circuit-level noise and can be applied to surface code volumes of arbitrary size. Their application removes errors arising from a certain number of faults, which serves to substantially reduce the syndrome density. Remaining errors can then be corrected by a global decoder, such as Blossom or union find, with their implementation significantly accelerated due to the reduced syndrome density. However, in the circuit-level setting, the corrections applied by the local decoder introduce many vertical pairs of highlighted vertices. To obtain a low syndrome density in the presence of vertical pairs, we consider a strategy of performing a syndrome collapse which removes many vertical pairs and reduces the size of the decoding graph used by the global decoder. We also consider a strategy of performing a vertical cleanup, which consists of removing all local vertical pairs prior to implementing the global decoder. By applying our local NN decoder and the vertical cleanup strategy to a d = 17 surface code volume, we show a

10
6

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speedup of the minimum-weight perfect matching decoder. Lastly, we estimate the cost of implementing our local decoders on field programmable gate arrays.
Tribotronics: an emerging field by coupling triboelectricity and semiconductors
Authors: Zhang Chi , Zhao Junqing , Zhang Zhi , Bu Tianzhao , Liu Guoxu , Fu Xianpeng
Published: July 2023

Highlights

The tribovoltaic effect is introduced as a phenomenon of direct current power generation by mechanical friction on the semiconductor interface.

The triboelectric modulation is elaborated by using the triboelectric potential on field effect transistors, which has demonstrated the active mechanosensation and nano-scale tactile perception.

The triboelectric management is presented for improving the energy supply efficiency, which can provide an effective microenergy solution for sensors and microsystems.

The research of tribotronics has exhibited the electronics of interfacial friction systems, and the triboelectric technology by electronics.
Observational and Genetic Evidence for Bidirectional Effects Between Red Blood Cell Traits and Diastolic Blood Pressure
Authors: He Zhen , Chen Zekai , de Borst Martin H , Zhang Qingying ,   International Consortium of Blood Pressure, Snieder Harold , Thio Chris H L
Published: July 2023

BACKGROUND

Previous studies have found associations of red blood cell (RBC) traits (hemoglobin and RBC count) with blood pressure; whether these associations are causal is unknown.

METHODS

We performed cross-sectional analyses in the Lifelines Cohort Study (n = 167,785). Additionally, we performed bidirectional 2 sample Mendelian randomization (MR) analyses to explore the causal effect of the 2 traits on systolic (SBP) and diastolic blood pressure (DBP), using genetic instrumental variables regarding hemoglobin and RBC identified in UK Biobank (n = 350,475) and International Consortium of Blood Pressure studies for SBP and DBP (n = 757,601).

RESULTS

In cross-sectional analyses, we observed positive associations with hypertension and blood pressure for both hemoglobin (odds ratio [OR] = 1.18, 95% confidence interval [CI]: 1.16–1.20 for hypertension; B = 0.11, 95% CI: 0.11–0.12 for SBP; B = 0.11, 95% CI: 0.10–0.11 for DBP, all per SD) and RBC (OR = 1.14, 95% CI: 1.12–1.16 for hypertension; B = 0.11, 95% CI: 0.10–0.12 for SBP; B = 0.08, 95% CI: 0.08–0.09 for DBP, all per SD). MR analyses suggested that higher hemoglobin and RBC cause higher DBP (inverse-variance weighted B = 0.11, 95% CI: 0.07–0.16 for hemoglobin; B = 0.07, 95% CI: 0.04–0.10 for RBC, all per SD). Reverse MR analyses (all per SD) suggested causal effects of DBP on both hemoglobin (B = 0.06, 95% CI: 0.03–0.09) and RBC (B = 0.08, 95% CI: 0.04–0.11). No significant effects on SBP were found.

CONCLUSIONS

Our results suggest bidirectional causal relationships of hemoglobin and RBC with DBP, but not with SBP.
Hypotensive Effects of Aquatic Exercise Training in Older Adults
Authors: Dunlap Emily , Alhalimi Taha , McLaurin Natalie , Tanaka Hirofumi
Published: July 2023

BACKGROUND

Although regular exercise can help reduce blood pressure (BP), older adults often struggle with adhering to land-based exercise due to barriers such as arthritis pain, functional limitations, and fear of falling. Aquatic exercise is a good alternative mode of exercise that may reduce barriers and improve adherence. However, limited evidence is available on the effectiveness of aquatic exercise in reducing BP in older adults with isolated systolic hypertension. This study aimed to determine the effects of an 8-week aquatic exercise program on arterial BP in older adults.

METHODS

Twenty-five participants were randomized to a control (n = 12, 81 ± 8 years) or aquatic exercise group (n = 13, 83 ± 7 years). The exercise group received aquatic cognitive-motor training at a moderate-intensity for 45 minutes per session three times per week for 8 weeks. The non-exercising control group received a 1-hour fall prevention seminar and was asked to maintain their normal physical activity level.

RESULTS

Baseline characteristics were not different between the groups. After 8 weeks, the exercise group had reductions in systolic BP (135 ± 11 vs. 126 ± 13 mm Hg, P < 0.01) and pulse pressure (PP) (68 ± 8 vs. 60 ± 8 mm Hg, P < 0.01) without significant change in diastolic BP. There were no significant changes in the control group.

CONCLUSION

Aquatic cognitive-motor training performed at a moderate-intensity was effective in inducing clinically meaningful reductions in systolic BP and PP in older adults.
Preference for Averaging in East Asian Faces: A Source of Potential Guidance in Aesthetic Plastic Surgery
Authors: Steppe Cyrus , Cinclair Richard , Wen Edward Yuan , Aly Al
Published: July 2023

Background

Relatively little research has been done on the application of objective tools in guiding Ethnic Plastic Surgery in Asian patients. The evolutionary psychology theory of koinophilia, or love of average features, presents the basis for a solution to build a foundation for crowd-sourced East Asian aesthetic standards.

Objectives

The authors hypothesize that the averaged composite face in a cohort will be viewed as significantly more attractive than their respective cohort.

Methods

Cohorts were created based on the gender of the individual in the photograph (40 females and 40 males of East Asian descent). Two surveys were created, 1 for the female cohort and the other for the male. The surveys assessed the aesthetic preference of each photograph using a Likert scale ranging from 1 to 7. Surveys were distributed using the popular crowdsourcing program Amazon Mechanical Turk (Amazon, Seattle, WA).

Results

The authors received 875 respondents for the male cohort survey and 876 respondents for the female cohort survey. For both the female and male cohorts, the composite images had a statistically significantly higher rating (P < .001) than the mean of the other images. Among other significant demographic findings, when considering both ethnicity and location of residence, Asian raters living in Asia preferred the composite significantly more than Asian raters living in North America (P < .001).

Conclusions

Raters’ preference for the composite average face is in concordance with the evolutionary psychology literature. Thus, this study affirms the utility of using facial composites to guide surgeons in identifying aesthetic standards for patients of East Asian descent.
Feature weighted models to address lineage dependency in drug-resistance prediction from Mycobacterium tuberculosis genome sequences
Authors: Billows Nina , Phelan Jody E , Xia Dong , Peng Yonghong , Clark Taane G , Chang Yu-Mei
Published: July 2023

Motivation

Tuberculosis (TB) is caused by members of the Mycobacterium tuberculosis complex (MTBC), which has a strain- or lineage-based clonal population structure. The evolution of drug-resistance in the MTBC poses a threat to successful treatment and eradication of TB. Machine learning approaches are being increasingly adopted to predict drug-resistance and characterize underlying mutations from whole genome sequences. However, such approaches may not generalize well in clinical practice due to confounding from the population structure of the MTBC.

Results

To investigate how population structure affects machine learning prediction, we compared three different approaches to reduce lineage dependency in random forest (RF) models, including stratification, feature selection, and feature weighted models. All RF models achieved moderate-high performance (area under the ROC curve range: 0.60–0.98). First-line drugs had higher performance than second-line drugs, but it varied depending on the lineages in the training dataset. Lineage-specific models generally had higher sensitivity than global models which may be underpinned by strain-specific drug-resistance mutations or sampling effects. The application of feature weights and feature selection approaches reduced lineage dependency in the model and had comparable performance to unweighted RF models.

Availability and implementation

https://github.com/NinaMercedes/RF_lineages.
MOViDA: multiomics visible drug activity prediction with a biologically informed neural network model
Authors: Ferraro Luigi , Scala Giovanni , Cerulo Luigi , Carosati Emanuele , Ceccarelli Michele
Published: July 2023

Motivation

The process of drug development is inherently complex, marked by extended intervals from the inception of a pharmaceutical agent to its eventual launch in the market. Additionally, each phase in this process is associated with a significant failure rate, amplifying the inherent challenges of this task. Computational virtual screening powered by machine learning algorithms has emerged as a promising approach for predicting therapeutic efficacy. However, the complex relationships between the features learned by these algorithms can be challenging to decipher.

Results

We have engineered an artificial neural network model designed specifically for predicting drug sensitivity. This model utilizes a biologically informed visible neural network, thereby enhancing its interpretability. The trained model allows for an in-depth exploration of the biological pathways integral to prediction and the chemical attributes of drugs that impact sensitivity. Our model harnesses multiomics data derived from a different tumor tissue sources, as well as molecular descriptors that encapsulate the properties of drugs. We extended the model to predict drug synergy, resulting in favorable outcomes while retaining interpretability. Given the imbalanced nature of publicly available drug screening datasets, our model demonstrated superior performance to state-of-the-art visible machine learning algorithms.

Availability and implementation

MOViDA is implemented in Python using PyTorch library and freely available for download at https://github.com/Luigi-Ferraro/MOViDA. Training data, RIS score and drug features are archived on Zenodo https://doi.org/10.5281/zenodo.8180380.
A qualitative exploration of patient experiences in pyoderma gangrenosum
Authors: Herbert Samantha , Haughton Reneé , Liakos William  , Wang Jenny , Ji-Xu Antonio , Le Stephanie T , Maverakis Emanual
Published: July 2023

Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis that is associated with a decreased quality-of-life (QoL). There are no PG-specific patient-reported outcome measures. In this exploratory study, we use patient interviews to define QoL domains in PG that will inform future outcomes measures.
Effect of obesity on perioperative outcomes following gastrointestinal surgery: meta-analysis
Authors: Cullinane Carolyn , Fullard Anna , Croghan Stefanie M , Elliott Jessie A , Fleming Christina A
Published: July 2023

Background

Obesity can pose perioperative challenges related to obesity-associated co-morbidities and technical factors. However, the true impact of obesity on postoperative outcomes is not well established and reports are conflicting. The aim was to perform a systematic review and meta-analysis to explore the effect of obesity on perioperative outcomes for general surgery procedures in distinct obesity subtypes.

Methods

A systematic review was performed for studies reporting postoperative outcomes in relation to BMI in upper gastrointestinal, hepatobiliary and colorectal based on an electronic search using the Cochrane Library, Science Direct, PubMed and Embase up to January 2022. The primary outcome was the incidence of 30-day postoperative mortality among patients with obesity undergoing general surgical procedures in comparison to patients with normal range BMI.

Results

Sixty-two studies, including 1 886 326 patients, were eligible for inclusion. Overall, patients with obesity (including class I/II/II) had lower 30-day mortality rates in comparison to patients with a normal BMI (odds ratio (OR) 0.75, 95 per cent c.i. 0.66 to 0.86, P < 0.0001, I2 = 71 per cent); this was also observed specifically in emergency general surgery (OR 0.83, 95 per cent c.i. 0.79 to 0.87, P < 0.0000001, I2 = 7 per cent). Compared with normal BMI, obesity was positively associated with an increased risk of 30-day postoperative morbidity (OR 1.11, 95 per cent c.i. 1.04 to 1.19, P = 0.002, I2 = 85 per cent). However, there was no significant difference in postoperative morbidity rates between the cohorts of patients with a normal BMI and class I/II obesity (OR 0.98, 95 per cent c.i. 0.92 to 1.04, P = 0.542, I2 = 92 per cent). Overall, the cohort with obesity had a higher rate of postoperative wound infections compared with the non-obese group (OR 1.40, 95 per cent c.i. 1.24 to 1.59, P < 0.0001, I2 = 82 per cent).

Conclusion

These data suggest a possible ‘obesity paradox’ and challenge the assumption that patients with obesity have higher postoperative mortality compared with patients with normal range BMI. Increased BMI alone is not associated with increased perioperative mortality in general surgery, highlighting the importance of more accurate body composition assessment, such as computed tomography anthropometrics, to support perioperative risk stratification and decision-making.

Registration number

CRD42022337442 (PROSPERO https://www.crd.york.ac.uk/prospero/).
Oncological outcomes after pancreatoduodenectomy for pancreatic ductal adenocarcinoma in octogenarians: case-control study
Authors: Pande Rupaly , Attard Joseph A , Al-Sarireh Bilal , Bhogal Ricky Harminder , Farrugia Alexia , Fusai Giuseppe , Harper Simon , Hidalgo-Salinas Camila , Jah Asif , Marangoni Gabriele , Mortimer Matthew , Pizanias Michail , Prachialias Andreas , Roberts Keith J , Hee Chloe Sew , Soggiu Fiammetta , Srinivasan Parthi , Chatzizacharias Nikolaos A
Published: July 2023

Background

By the end of this decade, 70 per cent of all diagnosed pancreatic ductal adenocarcinomas will be in the elderly. Surgical resection is the only curative option. In the elderly perioperative mortality is higher, while controversy still exists as to whether aggressive treatment offers any survival benefit. This study aimed to assess the oncological benefit of pancreatoduodenectomy in octogenarians with pancreatic ductal adenocarcinoma.

Method

Retrospective multicentre case-control study of octogenarians and younger controls who underwent pancreatoduodenectomy for pancreatic ductal adenocarcinoma between 2008 and 2017. The primary endpoint was overall survival and the secondary endpoint was disease-free survival.

Results

Overall, 220 patients were included. Although the Charlson co-morbidity index was higher in octogenerians, Eastern Cooperative Oncology Group performance status, ASA and pathological parameters were comparable. Adjuvant therapy was more frequently delivered in the younger group (n = 80, 73 per cent versus n = 58, 53 per cent, P = 0.006). There was no significant difference between octogenarians and controls in overall survival (20 versus 29 months, P = 0.095) or disease-free survival (19 versus 22 months, P = 0.742). On multivariable analysis, age was not an independent predictor of either oncological outcome measured.

Conclusion

Octogenarians with pancreatic ductal adenocarcinoma of the head and uncinate process may benefit from comparable oncological outcomes to younger patients with surgical treatment. Due to the age- and disease-related frailty and co-morbidities, careful preoperative assessment and patient selection is of paramount importance.
Expectations versus Reality: Achieving Impact from Social Work Practitioner Research in Challenging Circumstances
Authors: Power Lorne , Dean Laurel
Published: July 2023

This reflective article examines the claim that social work practitioner research is more likely to lead to impact. We reflect on the impact that we achieved as part of a social work practitioner research within an acute hospital in the South-East of England. First, we explore the literature on social work practitioner research and impact. Second, we outline our original research project. Third, we examine the individual, organisational and cultural impact we believe we achieved before reflecting on how our views and motivation towards impact changed throughout the research journey. Fourth, we discuss the barriers to achieve our original impact aspirations and reflect on the factors influencing our energy and motivation to achieve impact. Finally, we reflect on the factors that enabled us to achieve impact.
Impact of race/ethnicity and socioeconomic status on incident and prevalent esophageal cancer in patients with Barrett’s esophagus
Authors: Zhou Margaret J , Ladabaum Uri , Triadafilopoulos George , Clarke John O
Published: July 2023

The impact of race/ethnicity (RE) or socioeconomic status (SES) on progression from Barrett’s esophagus (BE) to esophageal cancer (EC) is not well established. We aimed to evaluate the association between demographic factors and SES on EC diagnosis in an ethnically diverse BE cohort. Patients aged 18–63 with incident BE diagnosed in October 2015–March 2020 were identified in the Optum Clinformatics DataMart Database. Patients were followed until the diagnosis of prevalent EC <1 year or incident EC ≥1 year from BE diagnosis, or until the end of their continuous enrollment period. Cox proportional hazards analysis was used to determine associations between demographics, SES factors, BE risk factors, and EC. Demographics of the 12,693 patients included mean age of BE diagnosis 53.0 (SD 8.5) years, 56.4% male, 78.3% White/10.0% Hispanic/6.4% Black/3.0% Asian. The median follow-up was 26.8 (IQR 19.0–42.0) months. In total, 75 patients (0.59%) were diagnosed with EC (46 [0.36%] prevalent EC; 29 [0.23%] incident EC), and 74 patients (0.58%) developed high-grade dysplasia (HGD) (46 [0.36%] prevalent HGD; 28 [0.22%] incident HGD). Adjusted HR (95% CI) for prevalent EC comparing household net worth ≥$150,000 vs. <$150,000 was 0.57 (0.33–0.98). Adjusted HRs (95% CI) for prevalent and incident EC comparing non-White vs. White patients were 0.93 (0.47–1.85) and 0.97 (0.21–3.47), respectively. In summary, a lower SES, captured by the household net worth, was associated with prevalent EC. There was no significant difference in prevalent or incident EC among White vs. non-White patients. EC progression in BE may be similar among racial/ethnic groups, but SES disparities may impact BE outcomes.
Catheter-directed mechanical thrombectomy in a patient with high-risk pulmonary embolism complicated by out-of-hospital cardiac arrest: a case report
Authors: Thangavel Shifan , Korsholm Kasper , Veien Karsten Tange , Larsen Kim M , Andersen Asger
Published: July 2023

Background

Pulmonary embolism (PE) is common, and it is the third leading cause of cardiovascular death. The management of patients with high-risk PE generally consists of systemic thrombolysis; however, surgical or catheter-directed treatment (CDT) can be considered in selected cases.

Case summary

A 78-year-old female patient presenting with acute severe dyspnoea develops out-of-hospital cardiac arrest (OHCA). She was admitted with return of spontaneous circulation and a critical haemodynamic state upon arrival to the catheterization laboratory with an estimated no-flow time of 1 min and low-flow time of 52 min. An acute pulmonary angiogram reveals massive PE. After a PE response team conference, the patient was not found eligible for extracorporeal membrane oxygenation, surgery, or thrombolysis. The patient was treated with catheter-directed mechanical thrombectomy 129 min after first medical contact. The patient recovered and was discharged without any neurological deficits.

Discussion

Catheter-directed mechanical thrombectomy was a successful treatment in a patient with OHCA secondary to high-risk PE, where thrombolysis and surgical interventions were considered contraindicated. This case underlines the future perspectives of CDT and also that a multidisciplinary team approach may benefit patients with high-risk PE.
Pitfalls for the non-invasive diagnosis of wild-type transthyretin amyloid cardiomyopathy in a young adult: a case report
Authors: Chang Hao-Chih , Kuo Ling , Chung Fa-Po , Yu Wen-Chung
Published: July 2023

Background

Using technetium (Tc)-labelled pyrophosphate (PYP) cardiac scintigraphy, a non-invasive diagnosis of transthyretin amyloid (ATTR) cardiomyopathy can be made without histopathological confirmation. In patients suspected of ATTR cardiomyopathy, however, atypical presentations may necessitate further investigation.

Case summary

A 30-year-old man with hypertension and end-stage renal disease on peritoneal dialysis presented with progressive exertional dyspnoea. Left ventricular hypertrophy (LVH) with a maximal end-diastolic wall thickness up to 16 mm was detected on echocardiography. Speckle-tracking analysis revealed a reduced longitudinal strain of left ventricle with a relative apical sparing pattern. Although the absence of monoclonal gammopathy, a grade 3 myocardial uptake in 99mTc-PYP cardiac scintigraphy, and negative TTR gene mutation inferred the diagnosis of wild-type ATTR, the relative youth of the patient still raised concerns regarding the diagnosis. Under clinical doubt, he underwent further testing. In non-contrast cardiac magnetic resonance (CMR) with native T1 mapping, the native T1 myocardial value was within the normal range. In endomyocardial biopsy (EMB), there was no evidence of amyloid deposition, negative Congo red staining, and no immunohistochemical evidence of transthyretin expression. These results excluded the diagnosis of ATTR cardiomyopathy and prevented subsequent unnecessary treatments.

Discussion

When patients with unexplained LVH meet the non-invasive diagnostic criteria for ATTR cardiomyopathy, an EMB should be considered in selected cases. Patients presenting at an atypical age for wild-type ATTR cardiomyopathy, absence of extracardiac symptoms/signs or classic electrocardiogram features for cardiac amyloidosis should be suspected of another diagnosis and require further CMR or EMB to confirm.
Body surface potential mapping detects early disease onset in plakophilin-2-pathogenic variant carriers
Authors: Kloosterman Manon , Boonstra Machteld J , Roudijk Rob W , Bourfiss Mimount , van der Schaaf Iris , Velthuis Birgitta K , Eijsvogels Thijs M H , Kirkels Feddo P , van Dam Peter M , Loh Peter
Published: July 2023

Aims

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a progressive inherited cardiac disease. Early detection of disease and risk stratification remain challenging due to heterogeneous phenotypic expression. The standard configuration of the 12 lead electrocardiogram (ECG) might be insensitive to identify subtle ECG abnormalities. We hypothesized that body surface potential mapping (BSPM) may be more sensitive to detect subtle ECG abnormalities.

Methods and results

We obtained 67 electrode BSPM in plakophilin-2 (PKP2)-pathogenic variant carriers and control subjects. Subject-specific computed tomography/magnetic resonance imaging based models of the heart/torso and electrode positions were created. Cardiac activation and recovery patterns were visualized with QRS- and STT-isopotential map series on subject-specific geometries to relate QRS-/STT-patterns to cardiac anatomy and electrode positions. To detect early signs of functional/structural heart disease, we also obtained right ventricular (RV) echocardiographic deformation imaging. Body surface potential mapping was obtained in 25 controls and 42 PKP2-pathogenic variant carriers. We identified five distinct abnormal QRS-patterns and four distinct abnormal STT-patterns in the isopotential map series of 31/42 variant carriers. Of these 31 variant carriers, 17 showed no depolarization or repolarization abnormalities in the 12 lead ECG. Of the 19 pre-clinical variant carriers, 12 had normal RV-deformation patterns, while 7/12 showed abnormal QRS- and/or STT-patterns.

Conclusion

Assessing depolarization and repolarization by BSPM may help in the quest for early detection of disease in variant carriers since abnormal QRS- and/or STT-patterns were found in variant carriers with a normal 12 lead ECG. Because electrical abnormalities were observed in subjects with normal RV-deformation patterns, we hypothesize that electrical abnormalities develop prior to functional/structural abnormalities in ARVC.
Effect of fibrosis regionality on atrial fibrillation recurrence: insights from DECAAF II
Authors: Assaf Ala , Mekhael Mario , Noujaim Charbel , Chouman Nour , Younes Hadi , Feng Han , ElHajjar Abdelhadi , Shan Botao , Kistler Peter , Kreidieh Omar , Marrouche Nassir , Donnellan Eoin
Published: July 2023

Aims

The amount of fibrosis in the left atrium (LA) predicts atrial fibrillation (AF) recurrence after catheter ablation (CA). We aim to identify whether regional variations in LA fibrosis affect AF recurrence.

Methods and results

This post hoc analysis of the DECAAF II trial includes 734 patients with persistent AF undergoing first-time CA who underwent late gadolinium enhancement magnetic resonance imaging (LGE-MRI) within 1 month prior to ablation and were randomized to MRI-guided fibrosis ablation in addition to standard pulmonary vein isolation (PVI) or standard PVI only. The LA wall was divided into seven regions: anterior, posterior, septal, lateral, right pulmonary vein (PV) antrum, left PV antrum, and left atrial appendage (LAA) ostium. Regional fibrosis percentage was defined as a region’s fibrosis prior to ablation divided by total LA fibrosis. Regional surface area percentage was defined as an area’s surface area divided by the total LA wall surface area before ablation. Patients were followed up for a year with single-lead electrocardiogram (ECG) devices. The left PV had the highest regional fibrosis percentage (29.30 ± 14.04%), followed by the lateral wall (23.23 ± 13.56%), and the posterior wall (19.80 ± 10.85%). The regional fibrosis percentage of the LAA was a significant predictor of AF recurrence post-ablation (odds ratio = 1.017, P = 0.021), and this finding was only preserved in patients receiving MRI-guided fibrosis ablation. Regional surface area percentages did not significantly affect the primary outcome.

Conclusion

We have confirmed that atrial cardiomyopathy and remodelling are not a homogenous process, with variations in different regions of the LA. Atrial fibrosis does not uniformly affect the LA, and the left PV antral region has more fibrosis than the rest of the wall. Furthermore, we identified regional fibrosis of the LAA as a significant predictor of AF recurrence post-ablation in patients receiving MRI-guided fibrosis ablation in addition to standard PVI.
The opioid tramadol blocks the cardiac sodium channel Nav1.5 in HEK293 cells
Authors: Jia Lixia , Veldkamp Marieke W , Verkerk Arie O , Tan Hanno L
Published: July 2023

Aims

Opioids are associated with increased risk of sudden cardiac death. This may be due to their effects on the cardiac sodium channel (Nav1.5) current. In the present study, we aim to establish whether tramadol, fentanyl, or codeine affects Nav1.5 current.

Methods and results

Using whole-cell patch-clamp methodology, we studied the effects of tramadol, fentanyl, and codeine on currents of human Nav1.5 channels stably expressed in HEK293 cells and on action potential (AP) properties of freshly isolated rabbit ventricular cardiomyocytes. In fully available Nav1.5 channels (holding potential −120 mV), tramadol exhibited inhibitory effects on Nav1.5 current in a concentration-dependent manner with an IC50 of 378.5 ± 33.2 µm. In addition, tramadol caused a hyperpolarizing shift of voltage-gated (in)activation and a delay in recovery from inactivation. These blocking effects occurred at lower concentrations in partially inactivated Nav1.5 channels: during partial fast inactivation (close-to-physiological holding potential −90 mV), IC50 of Nav1.5 block was 4.5 ± 1.1 μm, while it was 16 ± 4.8 μm during partial slow inactivation. The tramadol-induced changes on Nav1.5 properties were reflected by a reduction in AP upstroke velocity in a frequency-dependent manner. Fentanyl and codeine had no effect on Nav1.5 current, even when tested at lethal concentrations.

Conclusion

Tramadol reduces Nav1.5 currents, in particular, at close-to-physiological membrane potentials. Fentanyl and codeine have no effects on Nav1.5 current.
An approach for prioritizing candidate genes from RNA-seq using preclinical cocaine self-administration datasets as a test case
Authors: Vannan Annika , Dell’Orco Michela , Perrone-Bizzozero Nora I , Neisewander Janet L , Wilson Melissa A
Published: July 2023

RNA-sequencing (RNA-seq) technology has led to a surge of neuroscience research using animal models to probe the complex molecular mechanisms underlying brain function and behavior, including substance use disorders. However, findings from rodent studies often fail to be translated into clinical treatments. Here, we developed a novel pipeline for narrowing candidate genes from preclinical studies by translational potential and demonstrated its utility in 2 RNA-seq studies of rodent self-administration. This pipeline uses evolutionary conservation and preferential expression of genes across brain tissues to prioritize candidate genes, increasing the translational utility of RNA-seq in model organisms. Initially, we demonstrate the utility of our prioritization pipeline using an uncorrected P-value. However, we found no differentially expressed genes in either dataset after correcting for multiple testing with false discovery rate (FDR < 0.05 or <0.1). This is likely due to low statistical power that is common across rodent behavioral studies, and, therefore, we additionally illustrate the use of our pipeline on a third dataset with differentially expressed genes corrected for multiple testing (FDR < 0.05). We also advocate for improved RNA-seq data collection, statistical testing, and metadata reporting that will bolster the field's ability to identify reliable candidate genes and improve the translational value of bioinformatics in rodent research.