bluuebunny/crossref_metadata_2025 huggingface dataset:
A Comparison of Graph-Theoretic Approaches for Resilient System of Systems Design
Authors: Chatterjee Abheek , Helbig Cade , Malak Richard , Layton Astrid
Published: November 2022

System of Systems (SoS) are networked integration of constituent systems that together achieve new capabilities not possible through the operation of any single system. SoS can be found across all aspects of modern life such as power grids, supply chains, and aerospace operations. Their resilience (being able to withstand and recover from disruptions) is a critical attribute whose evaluation is nontrivial and requires detailed disruption models. Engineers rely on heuristics (such as redundancy and localized capacity) for achieving resilience that often result in unacceptable operation costs, erosion of profits, over-consumption of natural resources, or unacceptable levels of waste or emissions. Graph-theoretic approaches provide a potential solution to this challenge as they can evaluate architectural characteristics without needing detailed performance simulations, supporting their use in early-stage SoS architecture selection. However, no consensus exists as to which graph-theoretic metrics are most valuable for SoS design and how they should be included in the design process. In this work, multiple graph-theoretic approaches are analyzed and compared, on a common platform, for their use as design tools for resilient SoS. The metrics Density, Total Degree Heterogeneity, Modularity, Specialized Predator Ratio, Generalization, Vulnerability, and Ecological Fitness are found to be viable options for the development of early stage resilient SoS design tools and operation-specific applications.
Human Hand Motion Prediction in Disassembly Operations
Authors: Liao Hao-yu , Zheng Minghui , Hu Boyi , Behdad Sara
Published: November 2022

The remanufacturing workforce can benefit from the capabilities of robotic technology, where robots can alleviate the labor-intensive nature of disassembly operations and help with handling toxic and hazardous materials. However, operators’ safety is an important aspect of human-robot collaboration in disassembly operations. This study focuses on predicting human hand motion to provide advanced information to disassembly robots when collaborating with humans. A prediction framework is proposed, which consists of two deep learning models, including convolutional long short-term memory (ConvLSTM) and You Only Look Once (YOLO). ConvLSTM forecasts the next-frame image using images from the disassembly process, and then the YOLO model identifies the human hand object on the predicted image resulting from ConvLSTM. The disassembly images collected from four desktop computers are used to train the ConvLSTM and YOLO. The results reveal that the combined framework of ConvLSTM and YOLO performs well in predicting human hand motion and locating the hand object. The outcomes highlight the need for developing deep learning models capable of recognizing human motion when working with different designs as often remanufacturing workforce have to deal with a wide range of products from different brands, models, and conditions.
Application Oriented Modelling and Simulation of an Innovative Parallel Robot for Single Incision Laparoscopic Surgery
Authors: Pisla Doina , Gherman Bogdan , Tucan Paul , Birlescu Iosif , Pusca Alexandru , Rus Gabriela , Pisla Adrian , Vaida Calin
Published: November 2022

Single-incision laparoscopic surgery (SILS) is on the path of becoming a standard procedure in minimally invasive surgery due to the outstanding results obtained both during and after the medical act, these being defined by the reduced hospitalization time, the reduced recovery time, and the reduced visibility of the incision. The paper presents the modeling and simulation of a new parallel robot concept with 6 Degrees of Freedom (DOF), called PARA-SILSROB used for the single incision laparoscopic surgery. The paper focuses on the inverse kinematics, the preliminary design, and the robot control system architecture of PARA-SILSROB. A CAD motion simulation validates the mathematical model using Siemens NX.
Identifying the Effects of Immersion on Design for Additive Manufacturing Evaluation of Designs of Varying Manufacturability
Authors: Mathur Jayant , Miller Scarlett R. , Simpson Timothy W. , Meisel Nicholas A.
Published: November 2022

The demand for additive manufacturing (AM) continues to grow as more industries look to integrate the technology into their product development. However, there is a deficit of designers skilled to innovate with this technology due to challenges in supporting designers with tools and education for their development in design for AM (DfAM). There is a need to introduce intuitive tools and knowledge to enable future designers to DfAM. Immersive virtual reality (VR) shows promise to serve as an intuitive tool for DfAM to aid designers during design evaluation. The goal of this research is to, therefore, identify the effects of immersion in design evaluation and study how evaluating designs for DfAM between mediums that vary in immersion, affects the results of the DfAM evaluation and the mental effort experienced from evaluating the designs. Our findings suggest that designers can use immersive and non-immersive mediums for DfAM evaluation without experiencing significant differences in the outcomes of the evaluation and the cognitive load experienced from conducting the evaluation. The findings from this work thus have implications for how industries can customize product and designer-talent development using modular design evaluation systems that leverage capabilities in immersive and non-immersive DfAM evaluation.
Finding Optimal Sequence of Mobile Manipulator Placements for Automated Coverage Planning of Large Complex Parts
Authors: Malhan Rishi , Gupta Satyandra K.
Published: November 2022

Sensors are widely used in the industry to collect information about a physical object. Operational range of the sensor is limited and therefore the sensor needs to be moved around a large complex part in order to capture complete information. Robot arm or manipulators can provide the degrees of freedom needed to maneuver the sensor through the complex geometry. However, a robotic arm has a limited workspace as well and cannot cover large parts. Mobile base can enhance the capability of the robotic arm by adding mobility to the arm and carrying the arm around the part. Mobile base will need to relocate around the part during the process. Relocating the mobile base increases execution time and also introduces uncertainty in the localization as mobile base moves inaccurately. It is important to reduce the number of mobile base repositioning and reduce execution time and uncertainty. In this paper, we develop a motion planner that finds the minimum number of mobile base placements in order to find robotic arm trajectories that can cover a large complex part using a RGB-D camera sensor. The planning problem, also known as optimal base sequencing, is challenging due to the immensity of the search space. The computation costs involved in inverse kinematics calculations also adds to the search time. A branch and bound search algorithm is developed with efficient branch guiding and pruning heuristics that quickly explores the search space. A capability map based method is developed to improve the search space construction time. Output of our method is an optimal sequence of base placements for the mobile base that will lead to minimum number of placements and execution time required for the process.
A Finite Element Model of an Electric Scooter for Simulating Traffic Accidents
Authors: Chontos Rafael , Grindle Daniel , Untaroiu Alexandrina , Doerzaph Zachary , Untaroiu Costin
Published: November 2022

In the past several years, injuries caused by electric scooter accidents have significantly increased in areas serviced by scooter ride-share companies. The majority of injuries observed are mild to moderate in severity. In this study, a FE model of an electric scooter accident was created to observe the effect that impact speed and the type of ground have on the risk of severe injury to the rider. A FE standing Hybrid III dummy was calibrated against the certification test data using optimization techniques. To model a scooter-bump accident, the calibrated HIII FE model was placed on the scooter to mimic how a rider would stand on an electric scooter. Three scooter-bump impact simulations were run where the impact speeds were either 4.48 m/s or 3.2 m/s. The ground was similarly switched between soil and concrete. The simulation where the dummy fell on a concrete surface resulted in the highest risk of severe injury to the rider. Furthermore, the results concurred with previous literature that the head/neck region presented one of the biggest risks of severe injury. It is believed that the models developed in this study could be used in future to improve the e-scooter riders’ safety by development of new safety.
Deep Learning of Cross-Modal Tasks for Conceptual Design of Engineered Products: A Review
Authors: Li Xingang , Wang Ye , Sha Zhenghui
Published: November 2022

Conceptual design is the foundational stage of a design process, translating ill-defined design problems to low-fidelity design concepts and prototypes. While deep learning approaches are widely applied in later design stages for design automation, we see fewer attempts in conceptual design for three reasons: 1) the data in this stage exhibit multiple modalities: natural language, sketches, and 3D shapes, and these modalities are challenging to represent in deep learning methods; 2) it requires knowledge from a larger source of inspiration instead of focusing on a single design task; and 3) it requires translating designers’ intent and feedback, and hence needs more interaction with designers and/or users. With recent advances in deep learning of cross-modal tasks (DLCMT) and the availability of large cross-modal datasets, we see opportunities to apply these learning methods to the conceptual design of product shapes. In this paper, we review 30 recent journal articles and conference papers across computer graphics, computer vision, and engineering design fields that involve DLCMT of three modalities: natural language, sketches, and 3D shapes. Based on the review, we identify the challenges and opportunities of utilizing DLCMT in 3D shape concepts generation, from which we propose a list of research questions pointing to future research directions.
Va

riable

R

esistance

S

uit (VARS) for Enhancing Resistance Training
Authors: Kadhim Ibrahim Falih , Aracena Alvial Alvaro Andres , Frankle Eric , Rios Carbonell Gabriel , Hosseini Saba M. , Fukuda David , Stout Jeffrey , Park Joon-Hyuk
Published: November 2022

Muscle disorders and induced muscle atrophy impose critical risks to the well-being of an individual, limiting normal activities of daily living. Several resistance training methods exist that have effectively reversed the progression of muscle atrophy. Weightlifting and hydrotherapy are the two widely practiced schemes for resistance training; however, there is the potential risk of excessive loads exerted on the muscles during weightlifting, and limited accessibility and cost are barriers to hydrotherapy. An alternative is using a resistance band. Some limitations include engaging multiple muscles/joints while only unidirectional resistance is feasible. To address these limitations, a VAriable Resistance Suit (VARS) is designed to provide speed-dependent, bi-directional, and variable resistance at a single joint. As a proof of concept, an elbow module of VARS is developed and validated experimentally. A pilot study shows the changes in flexor and extensor muscle activations in response to eight different levels of resistance modulated by VARS. The clinical implications of VARS remain as future work, but the functionalities implemented in the presented VARS prototype and preliminary results suggest that VARS could be a viable solution and complementary to existing tools and techniques utilized in resistance training.
A Synthetic Tradespace Model for Tradespace Analysis and Exploration
Authors: Turner Cameron J. , Masoudi Nafiseh , Stewart Hannah , Daniels Julia , Gorsich David , Rizzo Denise , Hartman Greg , Agusti Rachel , Skowronska Annette , Castanier Matt , Rapp Stephen H.
Published: November 2022

Tradespace analysis and exploration is used to frame a design problem. By taking stock of available technologies, predictions of the performance of a system defined from a combinatorial combination of technologies (from say a morphological matrix) can be made. Based on these assessments, tradeoffs between functional performance objectives (often termed simply Functional Objectives or FOs) can be made. The result of these performance tradeoffs or Trades, can then be used to define a target design space for a problem. That design space can then be characterized with criteria to determine the viability of the tradespace and the design problem.

However, the cost to develop the morphological matrix for the tradespace can be prohibitive. The tradespace at the US Army DEVCOM Ground Vehicle Systems Center (GVSC) took more than 2 years of effort by multiple staff and technical experts to develop and allows for the consideration of more than 1021 vehicles. To develop enhanced approaches to tradespace analysis and exploration to enhance programmatic decision-making, a simulated tradespace based on “synthetic data” is necessary. For tradespace studies within the Clemson University Virtual Prototyping of Ground Systems (VIPR-GS) it was necessary to develop a synthetic tradespace model to serve as a basis for evaluating improved approaches to tradespace analysis, exploration and decision-making methods.

Within this work, we describe the state-of-the-art for developing models of the tradespace, formulations of functional objectives and defined models to represent different synthetic variable types to produce a synthetic tradespace with far less effort. Using this approach, we demonstrate the development of an example of a synthetic tradespace for small semi-autonomous ground vehicles developed within the VIPR Center that can be used to evaluate vehicle designs for the Clemson Deep Orange Project Vehicle and at GVSC. Finally, we will explore how this tradespace model can be used to facilitate decision-making surrounding the tradespace in the future.
Personalized Product Design Through Digital Fabrication
Authors: Minnoye A. (Sander) L. M. , Tajdari Farzam , Doubrovski E. (Zjenja) L. , Wu Jun , Kwa Felix , Elkhuizen Willemijn S. , Huysmans Toon , Song Yu (Wolf)
Published: November 2022

Personalized designs bring added value to the products and the users. Meanwhile, they also pose challenges to the product design process as each product differs. In this paper, with the focus on personalized fit, we present an overview as well as details of the personalized design process based on design practice. The general workflow of personalized product design is introduced first. Then different steps in the workflow such as human data/parameters acquisition, computational design, design for digital fabrication, and product evaluation are presented. Tools and methods that are often used in different steps in the process are also outlined where in human data acquisition, 3D scanning, and digital human models are addressed. For computational design, the use of computational thinking tools such as abstraction, decomposition, pattern recognition and algorithms are discussed. In design for digital fabrication, additive manufacturing methods (e.g. FDM), and their requirements on the design are highlighted. For product evaluation, both functional evaluation and usability evaluation are considered and the evaluation results can be the starting point of the next design iteration. Finally, several case studies are presented for a better understanding of the workflow, the importance of different steps in the workflow and the deviations in the approach regarding different contexts. In conclusion, we intend to provide designers a holistic view of the design process in designing personalized products as well as help practitioners trigger innovations regarding each step of the process.
Design for Multi-Material Manufacturing Using Polyjet Printing Process: A Review
Authors: Chadha Charul , Olaivar Gabriel , Patterson Albert E. , Jasiuk Iwona M.
Published: November 2022

Additive manufacturing (AM) of thermosetting polymer materials has been a topic of interest since the early days of technology development but has not gotten the attention of the common thermoplastic processes. AM’s general capability to produce intricate geometries along with a wide range of material properties has made it one of the primary manufacturing options for multi-material manufacturing, a major niche for thermosetting resins and similar materials. These multi-material structures are formed by strategically placing materials with different mechanical properties to enhance material performance significantly. As a result, interest in multi-material additive manufacturing (MM-AM) has increased dramatically in the last decade. While on the one hand, MM-AM has introduced new opportunities for design engineers, on the other hand, it has also increased the design considerations required to manufacture the part successfully. This paper reviews the major literature on the topic from the perspective of product and material system design, focusing on the material jetting approach, most commonly known as the PolyJet process. Specific topics include design advancements, materials, and challenges while printing MM-AM components with PolyJet. Findings on four broad topics are discussed, including the effect of interface on material properties, testing standards, established material and material combinations, and design guidelines for MM-AM. Additional design criteria needed for MM-AM are summarized for design engineers to help create reliable components with predictable mechanical behavior.
Preliminary Modeling of Angle of Attack in Self-Rectifying Turbine Under High Rotational Speed
Authors: Wu Xian , Zuo Lei
Published: November 2022

Wave energy has the potential to contribute significant parts to the future energy system. Various Wave Energy Converters (WECs) have been proposed, modeled, and tested to harvest wave energy. However, to date, none of the proposed works have been used commercially. Here, we present a modelling of a cyclorotor type WEC with adjustable pitch angle. The angle of attack is optimized within the controllable range to match the total resultant force to the tangential direction. Instead of following a frequency matching between the cyclorotor and the wave, results show that higher rotational speed of the cyclorotor can significantly increase the output power.
Moisture barrier coating of AlN and Al2O3 multilayer film prepared by low-temperature atomic layer deposition
Authors: Saito K. , Yoshida K. , Miura M. , Kanomata K. , Ahmmad B. , Kubota S. , Hirose F.
Published: November 2022

AlN and Al2O3 multilayer films intended as moisture barriers were deposited on polyethylene naphthalate films by remote-type plasma-enhanced atomic layer deposition. The deposition temperatures for AlN and Al2O3 were 160 and 20 °C, respectively. It was assumed that the AlN and Al2O3 interface would suppress the formation of dislocations and pinholes that lead to moisture diffusion. The AlN top layer was expected to act as a water-resistant layer. The surface morphology and the crystallinity of the deposited film were investigated by atomic force microscopy (AFM) and x-ray diffraction, respectively. The gas barrier property of the multilayer film was determined by the water vapor transmission rate, which was measured as 1.3 × 10−3 g/m2/day at a temperature of 40 °C and a relative humidity (RH) of 90%. The AFM image showed that the AlN top layer remained unchanged during water vapor contact for 120 h at 40 °C and 90% RH. The applicability of the multilayer film as a moisture barrier coating for compound semiconductor devices is discussed.
Canonical correlation analysis as a feature extraction method to classify active sonar targets with shallow neural networks
Authors: Kubicek Bernice , Sen Gupta Ananya , Kirsteins Ivars
Published: November 2022

Sonar target recognition remains an active area of research due to the complex entanglement of features from various acoustic scatterers, background clutter, and distortion by waveguide propagation effects. An equally challenging issue is due to different acoustic echoes returned from the target (including different target elements) itself. This work investigates the sonar target classification problem from a statistical perspective and aims to extract salient target feature vectors. Specifically, a multivariate statistical method is employed, canonical correlation analysis (CCA), as a feature extraction technique prior to multi-class classification of active sonar field data. The intuition behind using CCA is that persistent features slowly morph over time due to the changing aspect angles and platform positions and can be represented by maximally correlated projections of consecutive pings. CCA is applied using a sliding window, and the projections are used as feature vectors to train a neural network classifier. The smallest increase in classification accuracy when comparing the projection feature vectors to unprocessed feature vectors was 10%. The largest increase was 34%. The results are further examined through the use of confusion matrices and layer-wise relevance propagation, which distributes the trained networks output score to the input layer.
The Operationalizing Intersectionality Framework
Authors: Kriger Debra , Keyser-Verreault Amélie , Joseph Janelle , Peers Danielle
Published: November 2022

Intersectional approaches are needed in sport research and administration to create significant changes in access, participation, and leadership. The operationalizing intersectionality framework—graphically represented as a wheel with spokes and points of traction—offers a nonexhaustive, evolving structure that can facilitate contextual, deliberate actions to disrupt overlapping systems of oppression. The framework was assembled to guide E-Alliance, the gender equity in sport in Canada research hub, in embodying its commitment to intersectional approaches and designed for broader application to sport. Current gender equity efforts mostly continue to prioritize the knowledge and needs of White, middle–upper-class, nondisabled, not fat, heteronormative, binary, cisgender women and have yet to achieve parity. Acting meaningfully on commitments to intersectional approaches means focusing on how axes work together and influence each other. The framework can help advance cultural sport psychology and ultimately improve athletic well-being.
AMPK-dependent phosphorylation of MTFR1L regulates mitochondrial morphology
Authors: Tilokani Lisa , Russell Fiona M. , Hamilton Stevie , Virga Daniel M. , Segawa Mayuko , Paupe Vincent , Gruszczyk Anja V. , Protasoni Margherita , Tabara Luis-Carlos , Johnson Mark , Anand Hanish , Murphy Michael P. , Hardie D. Grahame , Polleux Franck , Prudent Julien
Published: November 2022

Mitochondria are dynamic organelles that undergo membrane remodeling events in response to metabolic alterations to generate an adequate mitochondrial network. Here, we investigated the function of mitochondrial fission regulator 1-like protein (MTFR1L), an uncharacterized protein that has been identified in phosphoproteomic screens as a potential AMP-activated protein kinase (AMPK) substrate. We showed that MTFR1L is an outer mitochondrial membrane–localized protein modulating mitochondrial morphology. Loss of MTFR1L led to mitochondrial elongation associated with increased mitochondrial fusion events and levels of the mitochondrial fusion protein, optic atrophy 1. Mechanistically, we show that MTFR1L is phosphorylated by AMPK, which thereby controls the function of MTFR1L in regulating mitochondrial morphology both in mammalian cell lines and in murine cortical neurons in vivo. Furthermore, we demonstrate that MTFR1L is required for stress-induced AMPK-dependent mitochondrial fragmentation. Together, these findings identify MTFR1L as a critical mitochondrial protein transducing AMPK-dependent metabolic changes through regulation of mitochondrial dynamics.
Printable assemblies of perovskite nanocubes on meter-scale panel
Authors: Li Xiao , Xue Zhenjie , Chen Xiangyu , Qiao Xuezhi , Mo Guang , Bu Wensheng , Guan Bo , Wang Tie
Published: November 2022

Hierarchical assemblies of functional nanoparticles can have applications exceeding those of individual constituents. Arranging components in a certain order, even at the atomic scale, can result in emergent effects. We demonstrate that printed atomic ordering is achieved in multiscale hierarchical structures, including nanoparticles, superlattices, and macroarrays. The CsPbBr
3
perovskite nanocubes self-assemble into superlattices in ordered arrays controlled across 10 scales. These structures behave as single nanoparticles, with diffraction patterns similar to those of single crystals. The assemblies repeat as two-dimensional planar unit cells, forming crystalline superlattice arrays. The fluorescence intensity of these arrays is 5.2 times higher than those of random aggregate arrays. The multiscale coherent states can be printed on a meter-scale panel as a micropixel light-producing layer of primary-color photon emitters. These hierarchical assemblies can boost the performance of optoelectronic devices and enable the development of high-efficiency, directional quantum light sources.
Strain-induced van der Waals gaps in GeTe revealed by in situ nanobeam diffraction
Authors: Yu Yong , Xie Lin , Pennycook Stephen J. , Bosman Michel , He Jiaqing
Published: November 2022

Ordered germanium vacancies in germanium telluride thermoelectric material are called van der Waals (vdW) gaps, and they are beneficial for the thermoelectric performance of the material. The vdW gaps have been observed by atomic resolution scanning transmission electron microscopy, but their origin remains unclear, which prevents their extensive application in other materials systems. Here, we report that the occurrence of vdW gaps in germanium telluride is mainly driven by strain from the cubic-to-rhombohedral martensitic transition. Direct strain and structural evidence are given here by in situ nanobeam diffraction and in situ transmission electron microscopy observation. Dislocation theory is used to discuss the origin of vdW gaps. Our work here paves the way for self-assembling two-dimensional ordered vacancies, which establishes a previously unidentified degree of freedom to adjust their electronic and thermal properties.
Single-cell immune profiling reveals thymus-seeding populations, T cell commitment, and multilineage development in the human thymus
Authors: Cordes Martijn , Canté-Barrett Kirsten , van den Akker Erik B. , Moretti Federico A. , Kiełbasa Szymon M. , Vloemans Sandra A. , Garcia-Perez Laura , Teodosio Cristina , van Dongen Jacques J. M. , Pike-Overzet Karin , Reinders Marcel J. T. , Staal Frank J. T.
Published: November 2022

T cell development in the mouse thymus has been studied extensively, but less is known regarding T cell development in the human thymus. We used a combination of single-cell techniques and functional assays to perform deep immune profiling of human T cell development, focusing on the initial stages of prelineage commitment. We identified three thymus-seeding progenitor populations that also have counterparts in the bone marrow. In addition, we found that the human thymus physiologically supports the development of monocytes, dendritic cells, and NK cells, as well as limited development of B cells. These results are an important step toward monitoring and guiding regenerative therapies in patients after hematopoietic stem cell transplantation.
Lithospheric extension of the accretionary wedge: An example from the Lanling high-pressure metamorphic terrane in Central Qiangtang, Tibet
Authors: Liang Xiao , Wang Genhou , Cao Wentao , Forster Marnie A. , Lister Gordon S. , Gao Xi , Du Jinxue , Li Jiabin , Li Jinsheng , Wang Yaxi
Published: November 2022

Deciphering the exhumation mechanism of high-pressure−low-temperature (HP-LT) metamorphic rocks can provide important insights into the tectonic evolution of oceanic subduction zones at active continental margins. Here, we present a multidisciplinary study examining the exhumation tectonics of the Permo−Triassic eclogite-bearing HP-LT terranes of the Central Qiangtang metamorphic belt (CQMB) in the central Tibetan Plateau. Field geological relations and microscopic observations show that the HP-LT rocks in the Lanling area are separated from the epimetamorphic late Paleozoic ophiolite mélange of the hanging wall by low-angle detachment faults and primarily exhibit five stages of deformation. The HP-LT terranes were exhumed as a metamorphic core complex and show pervasive synexhumation top-to-the-SW and -S shear structures. The results of the petrological and mineralogical analysis and pseudosection modeling of retrograde eclogites indicate that these rocks are characterized by synexhumation mineral growth pulses with hairpin-type decompressional pressure-temperature trajectories. A compilation of previous geochronological data and our 40Ar/39Ar dating results of synexhumation minerals and shear bands in HP-LT rocks indicate continuous exhumation at ca. 244−215 Ma prior to the continental collision between the North Qiangtang Block (NQB) and South Qiangtang Block. Moreover, the CQMB is likely an autochthonous accretionary wedge resulting from northward subduction of the Paleo-Tethys Ocean beneath the NQB. Combined with ca. 243−230 Ma mantle upwelling to the north of Lanling, we infer that the CQMB, namely, the accretionary wedge of the Paleo-Tethys Ocean, experienced Middle−Late Triassic lithospheric extension in the NW-SE direction.
In Situ FTIR Spectroscopic Imaging of Asphaltene Deposition from Crude Oil under n-Heptane and Acetone Flows
Authors: Shalygin A. S. , Milovanov E. S. , Kovalev E. P. , Yakushkin S. S. , Kazarian S. G. , Martyanov O. N.
Published: November 2022

Asphaltene deposition from crude oil, induced by n-heptane and acetone flows in a microfluidic device, was studied by optical and FTIR spectroscopic imaging techniques in situ. It was found that n-heptane and acetone penetrate crude oil in completely different ways, which is responsible for the formation of deposits with different structures and chemical compositions. The contact of the n-heptane flow with crude oil leads to fast aggregation of asphaltenes at the interface, resulting in the formation of a compact deposit fixed to the surface. Subsequent slow diffusion of n-heptane into crude oil causes asphaltene aggregation and precipitation of loose deposits. In the case of acetone, the flocculant diffuses (faster than n-heptane) into crude oil, which results in removal of its soluble components and in the formation of deposits appearing as strips as well. The distribution of the functional groups (–OH(NH), CH2–CH3, C=O, C–O, S=O) in the deposits is spatially heterogeneous. The asphaltenes deposits formed at the flocculant-crude oil interface are richer in the functional groups than those formed during diffusion. No carbonyl groups were revealed in the deposits formed in the acetone flow, while oxygen-containing groups such as –OH(NH) and S=O were present, which was an unusual result.
Primary retroperitoneal PEComa: an incidental finding
Authors: Marinho Bárbara Monteiro , Canha António Gâmboa , Silva Donzília Sousa , Silva José Davide Pinto
Published: November 2022

Perivascular epithelioid cell neoplasm (PEComa) is a rare type of tumour, and primary retroperitoneal PEComa is rarer still. Although pulmonary lymphangioleiomyomatosis (LAM), angiomyolipomas and clear cell ‘sugar’ tumours of the lung are well described, relatively little is known about other members of the PEComa family. We describe a case of an asymptomatic retroperitoneal PEComa, lymphangioleiomyoma type, which appeared in a previously healthy middle-aged woman as an incidental finding, in a CT scan performed in the context of spontaneous pneumothorax. The patient underwent surgical excision of the tumour and the histopathological and immunohistochemical analysis of the surgical specimen made the definitive diagnosis. Although rare, reports of isolated retroperitoneal lymphangioleiomyoma and primary retroperitoneal PEComas NOS (not otherwise specified) are described in the literature, normally associated with pulmonary LAM. The patient’s pulmonary imaging was normal. Short-term re-examination did not detect any recurrence. We also provide a literature review of this rare group of tumours.
Klebsiella invasive syndrome: a challenging diagnosis
Authors: Bhide Poorva Prashant , Ketkar Apurva Avadhut , Almeligy Abdalrahman , Ricca Anthony
Published: November 2022

Klebsiella invasive syndrome is a rare condition that typically presents as a liver abscess with metastatic infection, with mortality rates as high as 14% potentially due to diagnostic delay by clinicians. Here, we present a case of a woman in her 60s, who presented with symptoms and signs consistent with meningitis, imaging findings suggestive of possible leptomeningeal carcinomatosis a long with areas of lung consolidation and abdominal nodules and lymphadenopathy, presumably metastatic malignancy. We diagnosed Klebsiella invasive syndrome and treated it conservatively with medical management, including a long course of intravenous antibiotic therapy and supportive care. This is an infrequently encountered clinical entity with potentially fatal consequences, and we hope to add to the existing literature on the subject and drive home the point that it should be considered in the differential diagnoses in the appropriate clinical scenario.
Mental health among the sugarcane industry farmers and non-farmers in Peru: a cross-sectional study on occupational health
Authors: Bazo-Alvarez Juan Carlos , Bazalar-Palacios Janina , Bazalar Jahaira , Flores Elaine C
Published: November 2022

Objective

Describe the occupational characteristics of farmer and non-farmer workers and investigate critical occupational risk factors for mental disorders in sugarcane farmers in Peru.

Method

We conducted a cross-sectional study with occupational health and safety focus among farmers and non-farmers. Mental disorder symptoms were evaluated through the local validated version of the 12-Item General Health Questionnaire (GHQ-12). We explored the association between mental disorder symptoms, work conditions and known occupational risk factors (weekly working hours, pesticide exposures, heat stress and heavy workload). Negative binomial regression models were fitted, and 95% CIs were calculated.

Results

We assessed 281 workers between December 2019 and February 2020. One hundred and six (37.7%) respondents identified themselves as farmworkers. The mean GHQ-12 scores for farmers and non-farmers were 3.1 and 1.3, respectively. In the fully adjusted multivariable model, mental disorder symptom counts among farmers were more than twice as high as those of non-farmers (β: 2.11; 95% CI: 1.48 to 3.01). The heavy workload increased the mean number of mental disorder symptoms by 68% (95% CI: 21% to 133%), and each additional working hour per day increased the mean number of mental disorder symptoms by 13% (95% CI: 1% to 25%).

Conclusion

Farmers have higher mental disorder symptoms than non-farmers. A heavy workload and more working hours per day are independently associated with more mental disorder symptoms. Our findings highlight the importance of including mental health within occupational programmes and early interventions tailored to sugarcane industrial mill workers in the Latin American context.
Optimisation of treatments for oralNeisseria gonorrhoeaeinfection: Pharmacokinetics Study (STI-PK project) – study protocol for non-randomised clinical trial
Authors: Kong Fabian Y S , Unemo Magnus , Lim Shueh H , Latch Ngaire , Williamson Deborah A , Roberts Jason A , Wallis Steven C , Parker Suzanne L , Landersdorfer Cornelia B , Yap Tami , Fairley Christopher K , Chow Eric P F , Lewis David A , Hammoud Mohamed A , Hocking Jane S
Published: November 2022

Introduction

Neisseria gonorrhoeaeinfections are common and incidence increasing. Oropharyngeal infections are associated with greater treatment failure compared with other sites and drive transmission to anogenital sites through saliva. Gonococcal resistance is increasing and new treatments are scarce, therefore, clinicians must optimise currently available and emerging treatments in order to have efficacious therapeutic options. This requires pharmacokinetic data from the oral cavity/oropharynx, however, availability of such information is currently limited.

Methods and analysis

Healthy male volunteers (participants) recruited into the study will receive single doses of either ceftriaxone 1 g, cefixime 400 mg or ceftriaxone 500 mg plus 2 g azithromycin. Participants will provide samples at 6-8 time points (treatment regimen dependent) from four oral sites, two oral fluids, one anorectal swab and blood. Participants will complete online questionnaires about their medical history, sexual practices and any side effects experienced up to days 5–7. Saliva/oral mucosal pH and oral microbiome analysis will be undertaken. Bioanalysis will be conducted by liquid chromatography-mass spectrometry. Drug concentrations over time will be used to develop mathematical models for optimisation of drug dosing regimens and to estimate pharmacodynamic targets of efficacy.

Ethics and dissemination

This study was approved by Royal Melbourne Hospital Human Research Ethics Committee (60370/MH-2021). The study results will be submitted for publication in peer-reviewed journals and reported at conferences. Summary results will be sent to participants requesting them. All data relevant to the study will be included in the article or uploaded as supplementary information.

Trial registration number

ACTRN12621000339853.
Sequencing of medical therapy in heart failure with a reduced ejection fraction
Authors: Savage Henry Oluwasefunmi , Dimarco Anthony David , Li Brian , Langley Samantha , Hardy-Wallace Amy , Barbagallo Rossella , Dungu Jason N
Published: November 2022

The management of heart failure with a reduced ejection fraction is a true success story of modern medicine. Evidence from randomised clinical trials provides the basis for an extensive catalogue of disease-modifying drug treatments that improve both symptoms and survival. These treatments have undergone rigorous scrutiny by licensing and guideline development bodies to make them eligible for clinical use. With an increasing number of drug therapies however, it has become a complex management challenge to ensure patients receive these treatments in a timely fashion and at recommended doses. The tragedy is that, for a condition with many life-prolonging drug therapies, there remains a potentially avoidable mortality risk associated with delayed treatment. Heart failure therapeutic agents have conventionally been administered to patients in the chronological order they were tested in clinical trials, in line with the aggregate benefit observed when added to existing background treatment. We review the evidence for simultaneous expedited initiation of these disease-modifying drug therapies and how these strategies may focus the heart failure clinician on a time-defined smart goal of drug titration, while catering for patient individuality. We highlight the need for adequate staffing levels, especially heart failure nurse specialists and pharmacists, in a structure to provide the capacity to deliver this care. Finally, we propose a heart failure clinic titration schedule and novel practical treatment score which, if applied at each heart failure patient contact, could tackle treatment inertia by a constant assessment of attainment of optimal medical therapy.
Examining injury-related mortality disparities for American Indians/Alaskan Natives in rural Wisconsin
Authors: Anibas Jakob
Published: November 2022

This study aims to identify potential injury-related mortality disparities for American Indians/Alaskan Natives (AI/ANs) within the rural counties of one US state, Wisconsin. The Wisconsin Interactive Statistics on Health database was used to compare injury-related mortality for AI/ANs and whites in rural counties from 2016 to 2020. Both unintentional and intentional injuries were examined. This study found that AI/ANs were 62% more likely to die of an injury compared with whites in rural counties (relative risk (RR): 1.62; 95% CI: 1.41 to 1.86). When looking at injury-related mortality across various age groups, the 18–44-year-old age group had the largest injury-related mortality gap for AI/ANs compared with whites (RR: 2.85; 95% CI: 2.36 to 3.44). This study presents evidence that AI/ANs face significant injury-related mortality disparities compared with whites in rural counties.
Morning report: how to do it
Authors: Samuels Martin A
Published: November 2022

Morning report is an important clinical learning activity in many neurological institutions. A long experience of these meetings allows identification of several components to enhance its success. Meetings are best if brief (one or two cases) and held regularly, preferably daily and early in the working day, with full in-person team engagement. A senior clinician should lead the meeting and commit to a single interpretation, without fear of being wrong. Although the environment is relaxed (refreshments typically provided), it is a working meeting and with the essential focus on the patient rather than the learners. The rich learning experience is greatly enhanced by a subsequent confidential email summary and interpretation of the case(s) sent to all participants.
Aetiology of extracranial carotid free-floating thrombus in a prospective multicentre cohort
Authors: Dowlatshahi Dar , Lum Cheemun , Menon Bijoy K , Bharatha Aditya , Dave Prasham , Puac-Polanco Paulo , Blacquiere Dylan , Stotts Grant , Shamy Michel , Momoli Franco , Thornhill Rebecca , Lun Ronda , Torres Carlos
Published: November 2022

Background

Carotid free-floating thrombi (FFT) in patients with acute transient ischaemic attack (TIA)/stroke have a high risk of early recurrent stroke. Management depends on aetiology, which can include local plaque rupture, dissection, coagulopathy, malignancy and cardioembolism. Our objectives were to classify the underlying aetiology of FFT and to estimate the proportion of patients with underlying stenosis requiring revascularisation.

Methods

We prospectively enrolled consecutive patients presenting to three comprehensive stroke centres with acute TIA/stroke and ipsilateral internal carotid artery FFT. The aetiology of FFT was classified as: carotid atherosclerotic disease, carotid dissection, cardioembolism, both carotid atherosclerosis and cardioembolism, or embolic stroke of uncertain source (ESUS). Patients with carotid atherosclerosis were further subclassified as having ≥50% or <50% stenosis.

Results

We enrolled 83 patients with confirmed FFT. Aetiological assessments revealed 66/83 (79.5%) had carotid atherosclerotic plaque, 4/83 (4.8%) had a carotid dissection, 10/83 (12%) had both atrial fibrillation and carotid atherosclerotic plaque and 3/83 (3.6%) were classified as ESUS. Of the 76 patients with atherosclerotic plaque (including those with atrial fibrillation), 40 (52.6%) had ≥50% ipsilateral stenosis.

Conclusions

The majority of symptomatic carotid artery FFT are likely caused by local plaque rupture, more than half of which are associated with moderate to severe carotid stenosis requiring revascularisation. However, a significant number of FFTs are caused by non-atherosclerotic mechanisms warranting additional investigations.
The generalized q-Wronskian solutions of the q-deformed constrained modified KP hierarchy
Authors: Yi Ge , Wang Wei , Tian Kelei , Xu Ying
Published: November 2022

In this paper, we give the form of [Formula: see text]-cmKP hierarchy generated by the gauge transformation operator [Formula: see text]. We show a necessary and sufficient condition to reduce the generalized [Formula: see text]-Wronskian solutions from the [Formula: see text]-mKP hierarchy to generalize [Formula: see text]-Wronskian solutions of [Formula: see text]-component [Formula: see text]-cmKP hierarchy.
Analytical study of the first collision time finiteness between two randomly moving particles in a fractured medium
Authors: Alzulaibani Alaa Awad , El-Hadidy Mohamed Abd Allah
Published: November 2022

This paper presents the stronger moment conditions which are sufficient to show the finiteness of the first collision time between [Formula: see text]-dimensional Gaussian jump particle and another [Formula: see text]-dimensional Brownian particle in a fractured medium. To obtain these conditions, we use the triangular arrays of the random sequence vector which gives all probable positions of the first collision at any time. This study is an extension of the analytical study which is detailed in Alzulaibani and El-Hadidy [Int. J. Mod. Phys. B 33(28) (2019) 1950334] using the uniform integrability conditions.
Some congruence of the generalized Alexander invariant for periodic virtual links
Authors: Kim Joonoh , Kim Kyoung-Tark
Published: November 2022

In this paper, we provide two new congruences of the generalized Alexander polynomial [Formula: see text] for periodic virtual links [Formula: see text]. We use the Yang–Baxter state model of [Formula: see text] introduced by Kauffman and Radford.
The Why and How of Social Media Entrepreneurs
Authors: Erpe Tina , Kotnik Patricia
Published: November 2022

Digital technologies are transforming economic activity and opening up new opportunities, such as those being exploited by digital entrepreneurs. We study influencers and bloggers as a specific type of digital self-employment and as an under-researched phenomenon of social media entrepreneurship. The aim of this study is to explore the entrepreneurial motivations of influencers and bloggers and to investigate the specifics of their entrepreneurial process. A qualitative research approach involving interviews with 10 social media entrepreneurs provides insights into additional dimensions they bring to the concepts from entrepreneurship research. Our findings reveal the accelerated dynamics of the experimentation phase of the entrepreneurial process, which presents both advantages and disadvantages for the entrepreneur. Public exposure is one of the biggest challenges for them, suggesting that legitimacy is a crucial resource for social media entrepreneurs. We also find that they did not enter entrepreneurship in a planned and purposeful manner, but became aware of the possibility of starting a business while pursuing their interests.
Early Warning Systems for Small Business: Insights from Across Europe
Authors: Gallagher Padraig , Doherty Tara , Stephens Simon
Published: November 2022

In this paper we propose that a crisis can be avoided by taking countermeasures, which are informed by an Early Warning System. An Early Warning System can help lessen the impact of crisis episodes and provide a systematic approach to the response of small business owners to challenges in their business environment. Following a review of the literature, we undertook data collection in two stages. In stage one, focus groups were conducted with small business owners in four European countries. In stage two we worked with an expert panel to refine and develop a set of indicators for an Early Warning System. It is envisaged that the set of indicators will serve as the basis for further thought and empiricism. We argue that a delay in crisis recognition curtails the scope and time for corrective action.