bluuebunny/crossref_metadata_2025 huggingface dataset:
Volar Lunate Facet Fractures of the Distal Radius: Fracture Mapping Using 3D CT Scans
Authors: Clarnette Jock , De Silva April , Eardley-Harris Nathan , MacLean Simon , Bain Gregory I.
Published: January 2022

Background Fractures of the distal radius involving the lunate facet at the volar articular surface are unstable injuries and are usually managed operatively. Management of these fractures is challenging as our understanding of the exact fracture characteristics and associated injuries to the carpus is poor.

Purpose This study aims to define the anatomy and associated injuries of lunate facet fractures using three-dimensional computed tomography (CT) scans and fracture mapping techniques.

Methods A consecutive series of CT wrists was analyzed to identify intra-articular fractures involving the lunate facet at the volar distal radius. Fractures were mapped onto standardized templates of the distal radius using previously described fracture mapping techniques. We also identified instabilities of the carpus including volar carpal translation, ulnar translocation, scapholunate diastasis, and distal radioulnar joint (DRUJ) instability.

Results We present 23 lunate facet fractures of the distal radius. The lunate facet fragment displaces in a volar and proximal direction and the lunate always articulates with the displaced fragment. The smaller fragments displace a greater amount, in a volar direction, with pronation. The fracture tends to occur between the origin of the short and long radiolunate ligaments.

Conclusion Lunate facet fractures are frequently comprised of osteoligamentous units of the distal radius involving the short and long radiolunate ligaments and the radioscaphocapitate ligament. Assessment and management of volar carpal subluxation, scapholunate instability, ulnar translocation, and DRUJ instability should be considered.

Clinical relevance Our mapping of these fractures contributes to our understanding of the anatomy and associated instabilities and will aid in surgical planning and decision making.
Efficient and controllable magnetization switching induced by intermixing-enhanced bulk spin–orbit torque in ferromagnetic multilayers
Authors: Zhang Kun , Chen Lei , Zhang Yue , Hong Bin , He Yu , Lin Kelian , Zhang Zhizhong , Zheng Zhenyi , Feng Xueqiang , Zhang Youguang , Otani Yoshichika , Zhao Weisheng
Published: January 2022

Spin–orbit torque induced ferromagnetic magnetization switching brought by injecting a charge current into strong spin–orbit-coupling materials is an energy-efficient writing method in emerging magnetic memories and spin logic devices. However, because of the short spin coherence length in ferromagnetic layers, the interfacial effective spin–orbit torque typically leads to high critical current density for switching thick ferromagnet, which goes against low-power and high-density requirements. Here, we experimentally demonstrate efficient bulk spin–orbit torque-driven perpendicular magnetization switching under relatively low critical current density in thick Pt/Co multilayers with gradient-induced symmetry breaking. Through tuning the thickness gradient of Pt, the spin–orbit torque efficiency and switching chirality can be highly controlled, which also indicates that net spin current arises from gradient. Meanwhile, x-ray absorption spectroscopy results reveal that the atomic intermixing can significantly enhance the spin–orbit torque efficiency through improving the strength of spin–orbit-coupling of Pt. We also establish a micromagnetic model by taking both gradient-induced and intermixing-enhanced spin–orbit torque into account to well describe the experimental observations. This work would blaze a promising avenue to develop novel spin–orbit torque devices for high-performance spintronic memory and computation systems.
Improved algorithms for determination of particle directions with Timepix3
Authors: Mánek P. , Bergmann B. , Burian P. , Garvey D. , Meduna L. , Pospíšil S. , Smolyanskiy P. , White E.
Published: January 2022

Timepix3 pixel detectors have demonstrated great potential for tracking applications. With 256 × 256 pixels, 55 µm pitch and improved resolution in time (1.56 ns) and energy (2 keV at 60 keV), they have become powerful instruments for characterization of unknown radiation fields. A crucial pre-processing step for such analysis is the determination of particle trajectories in 3D space from individual tracks. This study presents a comprehensive comparison of regression methods that tackle this task under the assumption of track linearity. The proposed methods were first evaluated on a simulation and assessed by their accuracy and computational time. Selected methods were then validated with a real-world dataset, which was measured in a well-known radiation field. Finally, the presented methods were applied to experimental data from the Large Hadron Collider. The best-performing methods achieved a mean absolute error of 1.99° and 3.90° in incidence angle θ and azimuth φ, respectively. The fastest presented method required a mean computational time of 0.02 ps per track. For all experimental applications, we present angular maps and stopping power spectra.
Simulations of geometric aspects for ARAPUCA designs
Authors: Adames M.R.
Published: January 2022

The photon detection system of DUNE Far Detector (FD) is based on ARAPUCA technology. The new version of ARAPUCA, named X-ARAPUCA, will be used in the first and second modules. As the second module is based on vertical drift, the design of the X-ARAPUCA needed to be changed and simulation studies are fundamental for the optimization of the device. This work presents the simulation studies of the design, size, shape, and SiPM positioning inside the reflective cavity. We designed a Python module that creates the geometry for the simulations based on given parameters such as size of the detector, numbers of SiPM and others. The physics of photons inside the X-ARAPUCA is simulated by a ray-tracer written in C++ using an uniform grid as acceleration structure. Our simulations focus on reflections and refractions using Snell’s law on the interfaces and the total internal reflections inside the wavelength shifting plate, that absorbs every incoming photon and re-emits them in a random direction. The simulation shows that the highest efficiency is reached for thin X-ARAPUCA with a square shape. Better efficiency is obtained for larger modules if one considers the number of SiPM per cm2 of the active collection area. Rectangular modules are more efficient when the SiPMs are positioned on the short side.
Preface
Authors: Bonora N , Cianetti F , Livieri P
Published: January 2022

The Italian Association for Stress Analysis (AIAS) was founded in 1971 by researchers from academia, research centers and industry. AIAS was intended as a community where to discuss, to share and to develop scientific knowledge related to all technical aspects of stress analysis. In the years, from an initial focus on experimental techniques, AIAS contributed considerably to the development of modern numerical methods and computational techniques for the mechanical engineering design. In 2015, AIAS turned in the Italian Scientific Society of Mechanical Engineering Design.

Today, AIAS is an institutional partner that supports the instances from academia in subject area of the mechanical engineering design. Every year, AIAS organizes a technical conference offering the possibility to present research updates, share new ideas and foster collaborations. The AIAS conference has become a fundamental event for all those interested in current developments in mechanical engineering design and stress analysis, where to meet researchers, testing equipment and software developers.

The 50th AIAS Conference edition was initially re-scheduled to be held in Genoa, Italy after it was switched as virtual conference in 2020 due to COVID-19 emergency. Unfortunately, due to the continuing pandemic emergency, it was decided to go virtual again to keep continuity with the tradition, confident that, despite the difficulties of the moment, united we stand.

As for the previous year, the response of researchers and students has been outstanding: over 180 oral contribution have been presented in synchronous, during the three days of the conference, with three simultaneous parallel sessions. In addition to the thematic sessions on AIAS traditional subjects, special sessions on additive manufacturing, energetic methods for structural analysis and smart materials and MEMS have been successfully organized with the contribution of the AIAS technical committees.

Among all contributions presented at the conference, 54 have been selected to be published after peer review, in this volume. This was made possible thanks to the active participation of all AIAS members, to the work of the AIAS Scientific Committee and Conference Papers Review panel (Profs Giovanni Meneghetti, AIAS Scientific Coordinator, Luciano Afferrante, Francesco Bucchi, Filippo Cianetti, Enrico Armentani, Marco Sasso). Their outstanding contribution is gratefully acknowledged.

List of Disclaimer, Editors, Scientific Committee are available in this pdf.
Effect of process parameters on the mechanical properties of a Titanium alloy fabricated by Electron Beam Melting (EBM)
Authors: Mirone G , Barbagallo R , Di Bella S
Published: January 2022

Electron Beam Melting is a layer-by-layer additive manufacturing technique which proved to be very efficient and versatile in the fabrication of medical devices and automotive or aerospace components. Due to the highly innovative character of the technology, its potential is not yet fully exploited and a comprehensive understanding of how the different processing parameters may affect the mechanical performance of the resulting materials still deserves to be achieved. Tensile tests on a Titanium alloy (Ti-6Al-4V-ELI) are ran at static rates for investigating the effects of different fabrication parameters on the material response, namely the speed function, the line offset, the focus offset, the number of contours and the horizontal-vertical growing direction of the specimens. A combination of such parameters is identified as a “process setup” and different setups are adopted for producing corresponding series of specimens, machined after fabrication according to ASTM F2924 and ASTM E8 regulations. The experimental procedure relies on enhanced true stress-true strain data based on the optical measurement of the neck cross section of the specimen, as an alternative to the traditional elongation-based approach to the true stress-true strain evaluation. This approach allows to better highlight the effects of the different process setups on the material performance, by focusing on the most stressed/strained material points within the overall specimen volume. The true curves allow to relate the material performance in terms of both strength and ductility to each process setup, allowing to outline the influence of single/combined fabrication parameters on the two above performance indicators.
Fracture mechanics of additive manufactured crack-like notches by digital image correlation
Authors: Minak Giangiacomo , Drvar Nenad
Published: January 2022

The rapid development of a variety of Additive Manufacturing (AM) techniques is witnessed by the large interest of the scientific community. Among the numerous new features offered by these techniques, very lately the possibility of including cracks of any shape, direction, and position inside AM samples to validate FEM models was explored. Therefore, the necessity arose of full-field measurement techniques that would allow the evaluation of the fracture mechanics parameters in the cases of both linear elastic and partially plastic materials, as a function of the fracture modes. Invented in the ’80 of the XX century, the Digital Image Correlation (DIC) in recent years has taken place in nearly every laboratory. It is used to measure displacements, and by numerical differentiation or coupling with Finite Element Method, to calculate strains at different spatial scales. In particular, two procedures that were successfully employed on a specific kind of specimens, based on DIC at a small scale near the crack-tip, in this paper are shown in detail.
Combined experimental methods to assess the fatigue limit
Authors: Fargione G , Giudice F , Barbagallo R , Corallo D , La Rosa G
Published: January 2022

Purpose of this paper is to perform an energetic analysis on metal specimens under fatigue testing using the simultaneous application of different non-destructive techniques: thermography (TH), acoustic emission (AE) and digital image correlation (DIC). They assure the better evaluation, being contactless methods, usable in real time and, even if TH and DIC are related to the specimen surface, representative of the inside state of the materials. In particular, the cascade of hits and the acoustic energy were recorded to assess the parameters linked to the fracture of the materials. At the same time, the surface temperature, detected by a thermocamera, and the displacements induced on the specimen, using the DIC on the free zone of the specimens, were recorded. The DIC analysis allows the evaluation of the correct displacement by a pattern realized on the opposite face respect to TH. AE data and hysteresis curves (derived by DIC) were compared with the measures acquired by TH and reveal a reliable correlation between them in terms of fatigue limit.
Analysis of fracture behaviour in active materials for lithium ion batteries
Authors: Clerici D , Mocera F , Pistorio F
Published: January 2022

Several strong points make lithium ion battery one of the most widespread energy storage system. Nevertheless, one of the biggest drawbacks is the progressive damage which affects active materials, and influences cycle life as well. The hosting process of lithium ions causes the rise of mechanical stress in active material, which ultimately leads to the propagation of micro-flaws already present in fresh material. Finally, the damage of active material and solid-electrolyte interphase growth caused by cracks propagation result in capacity drop. The distribution of Mode I stress intensity factor is calculated along the semi-elliptical crack front on the outer surface and in the core of a three-dimensional spherical active material particle. A 3D and 2D finite element method analysis is performed in ANSYS Mechanical APDL starting from the mechanical stress state in active material computed with the electrochemical-mechanical model presented in previous works. The model is built using collapsed singular elements along the crack front, the not-singular version of these elements is used to model the outlying region of the crack area. The dependence of stress intensity factor on geometry size is deepened to evaluate the most critical condition. Moreover, the influence of current rate on stress intensity factor is investigated, in order to identify a current threshold beyond stress intensity factor is greater than the toughness of active material, and cracks start to propagate.
Structural Health Monitoring of civil structures through FEM high-fidelity modelling
Authors: Mirasoli G , Brutti C , Groth C , Mancini L , Porziani S , Biancolini M E
Published: January 2022

FEM high-fidelity modeling is a useful method for evaluating the dynamic behavior of civil structures and their state of damage through the processing of real-time vibration data in the frame of the general Structural Health Monitoring. The development of reliable digital twin involves the use of high-fidelity models, which must be validated with experimental data. In this study, a prototype of a bridge, composed by a frame structure of steel beams and a slab made in concrete and asphalt, was considered. Two of the main beams have a bolted connection that have been used to simulate a local damage of the structure. FEM models have been validated with experimental data, thus they are able to evaluate both static and dynamic behavior of the bridge and its state of health, referred to benchmark structure. The bridge was degraded considering the breakage of one or more plates of the bolted connection, or an accidental overload capable of creating plastic deformations. The proposed models identify damage of the structure through two different methods: shift of natural frequencies, and evaluation of frequency response of the structure (FRF) at the sensor nodes. The second method is more suitable since the variations of observed variables is more consistent. Therefore, with these models, it is possible to carry out monitoring operations for the predictive maintenance of the structure and defining the limits that the observed variables can undergo in order to still consider the structure suitable for the operating loads.
Experimental investigation on crack propagation paths in spur gears
Authors: Curà F , Mura A , Corsaro L
Published: January 2022

Spur gears subjected to bending fatigue may nucleate cracks at the tooth root fillet. In thin rim gears these cracks may propagate in a safe way (through the tooth) or in catastrophic way (through the rim). Crack propagation direction is mainly influenced by both wheel geometry parameters and crack initiation point, as already pointed out by theoretical and numerical results available in literature. Aim of this work is to set up an experimental activity in order to verify the onset of the bending crack and its propagation path in spur gears with different geometries. In particular, a special device connected to a standard fatigue machine was realized to perform bending tests for both standard and thin rim gears. During bending tests, an IR thermocamera was utilized to monitor the surface thermal profile in the tooth root fillet zone.
Multiscale stress analysis of porosity clusters as mechanical models of degenerated graphite defects in cast iron
Authors: Rizzoni R , Livieri P , Tovo R
Published: January 2022

We extend previous results for the stress analysis of a cluster of degenerated graphite in spheroidal cast iron, modelled as a multiscale three-dimensional composite. At the microscale, precipitates of degenerated graphite are modelled as spheroidal voids in a linear elastic matrix. At the mesoscale, clusters of degenerated graphite are aggregates of spheroidal voids. These aggregates are studied by means of a numerical analysis based on finite element simulations. As a second approach, the clusters are seen as homogeneous inclusions made of an equivalent porous elastic material. The average elastic properties of the porous material are calculated using an approach proposed by Tandon and Weng and based on Eshelby’s equivalent principle and Mori-Tanaka’s estimate. Comparison of the two approaches gives encouraging results in terms of average properties.
Corrosion Resistance Behaviour of recycled AlSi10Mg alloy: Surface Morphology and Acoustic Emission Investigation
Authors: Barile C , Casavola C , Vimalathithan PK , Renna G
Published: January 2022

The corrosion resistance behaviour of recycled AlSi10Mg alloy prepared using Selective Laser Melting (SLM) process is investigated. The specimens are exposed to salt solution attack (5% NaCl) atomized in uniform droplets, inside a controlled Salt Spray Test (SST) chamber for 1000 h. The surface morphology of the specimens exposed to different predefined exposure times (0 h, 6 h, 48 h, 168 h, 480 h and 1000 h) are investigated under Scanning Electron Microscope (SEM). The SEM micrographs shows the salient features of the corrosion attack such as the formation both of pits and corrosion products on samples surface in different exposure times in the SST chamber. Similarly, the Acoustic Emission (AE) signals generated during the corrosion process are recorded for the different exposure times. The AE waveforms are studied using advanced waveform processing techniques. The waveforms, in their time-frequency domain, provide detailed information on the characteristic features of the acoustic source. The different AE sources have been characterized from the time-frequency analysis of the waveforms.
Simulation of freight trains with up to three traction units in radio communication
Authors: Cantone L
Published: January 2022

Paper reports the main results of a systematic study on longitudinal train dynamics (LTD) of long freight trains, equipped with radio communication. The simulation results have been used to prepare an experimental test campaign to test the Distributed Power System (DPS) technology. The simulations refer to up/down and level track and they compare the LTD of trains with and without DPS, for different train operations and radio link conditions. The DPS technology is proved (by simulations and test) to be a very effective way to increase the efficiency of future freight trains.
Development of a 2D finite element model for the investigation of the tread braked railway wheels thermo-mechanical behaviour
Authors: Magelli M
Published: January 2022

The main drawback of tread braking is the rail wheel heating due to friction sliding. Thermal stresses and strains can lead to wheel surface damages while at the same time fast cooling from high temperature can cause microstructural changes, with possible local formation of brittle martensite. Nowadays, the investigation of the wheel and shoe thermomechanical interaction is typically performed using finite element (FE) codes. The paper shows the development, implementation and preliminary validation of a 2D plane FE model for the calculation of the thermal field produced in a tread braked wheel due to drag and stop braking operations. The model includes a structural contact module for the static calculation of the normal and tangential contact pressure at the wheel-shoe interface and a thermal transient module, which computes the wheel temperature considering the friction heat flux and the cooling due to air convection and rail chill.
Vehicle stability controller HiL validation on static simulator
Authors: Alfatti F , Annicchiarico C , Capitani R
Published: January 2022

In the automotive world, Hardware in the Loop (HiL) methodologies are used to speed up the design and calibration process of the various mechatronics components installed on the vehicle. Installing production parts on advanced driving simulator enables the performance assessment in realistic scenarios, including a test driver earlier in the design process. The scope of this work is to evaluate the effect of ABS and ESC system, replicating their influence on the steering wheel. A brake by wire production system has been installed on a static simulator, equipped with a EPSiL steering bench, capable of accurately replicate tie-rod forces on a production steering unit. Full brake, sine steer maneuvers have been carried out both on real vehicle and on virtual environment. The system showed its capabilities of replicating the same functionalities of the real vehicle, extending the static simulator potentialities to support the activities on calibration and test of vehicle systems.
Energy harvester duty cycle evaluation for railway vehicle health monitoring
Authors: Russo C , Monaco M Lo , Somà A
Published: January 2022

The recent growth of the IoT (Internet of Things) technologies makes these connected devices suitable for monitoring and diagnostic in different applications. Through these devices, a wireless sensor network has become a smart solution for monitoring structures, vehicles, and other devices. Each node in the network can be placed in an inaccessible or unsafe location for human intervention and provide a real-time data stream, useful for the diagnostic and maintenance of the structure. In this context, the power node becomes a fundamental problem since the replacement of batteries is a disadvantage both for environmental disposal and for the related costs. Thus, the interest in the so-called AIOT (Autonomous Internet of Things) is growing, and the energy harvester generators can be a possible solution to this problem. In this scenario, an inductive linear generator having a non-symmetrical gravitational suspension is presented. The main characteristics of the generator and the magnetic suspension are introduced with the description of the Matlab/Simulink model that simulates the same behavior. In this work, a first study of the duty cycle of the generator to power a wireless sensor node for industrial application is presented as well. This study is carried out with a particular focus on the acceleration frequency evaluation of railway vehicles to better understand the possible effective power that can be extracted from the harvester. The relevance of this work lies in the fact that the generator sizing cannot be separated from the detailed knowledge of the energy source and of the sensing/monitoring system that must be powered.
Numerical investigations on a photonic nanojet coupled plasmonic system for photonic applications
Authors: Agrawal Tulika , Dey Soumyodeep , Bhattacharya Shubhayan , Singh Gurvinder , Bisht Prem B
Published: January 2022

A photonic nanojet (PNJ) from a microcavity is a narrow and intense beam of light used to enhance the emerging electric field. Metal nanoparticles (NPs), on the other hand, confine a strong field in their vicinity due to the resonance of the free electrons with the incident field. A hybrid combination of a microcavity with a NP can drastically enhance the output field. In this work, a systematic numerical study of the microcavity-NP system has been carried out to investigate the effect of the shape of the metal NPs on the output field strength. The single and their dimer NPs with different dimer nanogaps with PNJ producing microcavity have been investigated. Splitting of the broad dipole mode of the NP has also been observed. As an application of this study, the surface enhanced Raman spectroscopy factor of the order of 107 has been estimated for nano-cube dimer NP-microcavity hybrid system.
Analysis on the localized corrosion of hydraulic support after short-term service in coal mine
Authors: Chen Jie , Liu Yanjia , Yuan Juntao , Zan Chaofei , Huang Lezheng , Zhang Huihui
Published: January 2022

The corrosion of hydraulic support has brought huge economic losses to coal enterprises. Using laser cladding stainless steel coating on the surface can improve its wear resistance and corrosion resistance. However, dense corrosion pits appeared on the hydraulic support coated 304 stainless steel after 25 d use in a coal mine. At present, there are few studies on the corrosion effect of this laser cladding layer under the actual mine. In this work, the oxide scales are characterized by 3D Optical Microscope (OM), Scanning Electron Microscopy (SEM) equipped with x-ray Energy Spectrometer (EDS), x-ray Photoelectron Spectrometer (XPS) and x-ray Diffraction (XRD) techniques. Based on the results, the localized corrosion mechanism is discussed. It was found that the corrosion products were mainly a mixture of (Fe,Cr)2O3 and CaCO3. The maximum pitting rate calculated from the depth data of pits. which were collected by ultra-depth of field optical microscopy, was 2.32 mm a−1. The mechanism of corrosion of hydraulic support was discussed form perspectives of the under-deposit corrosion and corrosive ions (i.e. Cl− and S2)− in the environment.
Physical characterization and biological tests of bioactive titanium surfaces prepared by short-time micro-arc oxidation in green electrolyte
Authors: Zaniolo Karina M , Biaggio Sonia R , Cirelli Joni A , Cominotte Mariana A , Bocchi Nerilso , Rocha-Filho Romeu C
Published: January 2022

Titanium (Ti) and its alloys are the most used biomaterials in dental and orthopedic implant applications. However, despite the good performance of these materials, implants may fail; therefore, several surface modification methodologies have been developed to increase the bioactivity of the metal surface, accelerating the osseointegration process while promoting improved corrosion performance. In this work, the production of a TiO2 coating on titanium through a short-time micro-arc oxidation (MAO) in a green electrolyte (obtained by a mixed solution of K3PO4 and Ca(CH3COO)2.H2O) is proposed, aiming at obtaining a porous oxide layer with Ca and P incorporation through an environmentally friendly experimental condition. The morphology, chemical composition, crystalline structure, wettability, hardness and bioactivity of the modified Ti surfaces were characterized. The MAO process at 250 V for 1 min in the green electrolyte solution allowed the production of a highly porous oxide surface in the anatase crystalline phase, with effective Ca and P incorporation. Pre-osteoblastic cells were used in in-vitro assays to analyze viability, adhesion, proliferation and ability to perform extracellular matrix mineralization on the Ti surfaces (polished and MAO-treated Ti). The MAO-treated Ti surface exhibited better results in the bioactivity tests, presenting more calcium phosphate precipitates. This surface also presented higher hardness, lower hydrophilicity and better performance in biological tests than the polished surface. The here-reported MAO-treated Ti surface is promising for dental implants, especially in patients having poor bone quality that requires greater stimulation for osteogenesis.
B-dot probe measurements on plasma plume expansion across the magnetic field
Authors: Behera Narayan , Singh R K , Prakash G Veda , Patel Kiran , Joshi H C , Kumar Ajai
Published: January 2022

Time-varying diamagnetism in laser-produced plasma moving across a transverse magnetic field for different field strengths has been studied using fast imaging and magnetic probe. The emphasis of the present work is on the development of suitable B-dot probe, quantitative analysis of induced diamagnetic field in an expanding plasma plume and its effect on the applied magnetic field profiles. A Helmholtz coil with pulsed power system is used to produce uniform magnetic field varying from 0.13 T to 0.57 T. Helmholtz coil allows the plume imaging along the magnetic field lines, which gives the direct structural information of the induced diamagnetic cavity. A high frequency three-axis B-dot probe has been developed to measure the transient magnetic field. Different experimental approaches have been used to test the response, sensitivity and calibration of the developed probe. It has been observed that induced magnetic field displaced the external magnetic field that is plasma plume shows the diamagnetic behaviour for considered magnetic field range. The probe signals in directions orthogonal to the applied/induced magnetic lines are correlated with the distortion in applied magnetic field in three dimensional space, which is consistent with recently simulated topology of external magnetic field in similar experimental conditions [Patel et al, 2021 Plasma Phys. Control. Fusion
63 115020 ].
Clinical validation of an artificial intelligence-assisted algorithm for automated quantification of left ventricular ejection fraction in real time by a novel handheld ultrasound device
Authors: Papadopoulou Stella-Lida , Sachpekidis Vasileios , Kantartzi Vasiliki , Styliadis Ioannis , Nihoyannopoulos Petros
Published: January 2022

Aims

We sought to evaluate the reliability and diagnostic accuracy of a novel handheld ultrasound device (HUD) with artificial intelligence (AI) assisted algorithm to automatically calculate ejection fraction (autoEF) in a real-world patient population.

Methods and results

We studied 100 consecutive patients (57 ± 15 years old, 61% male), including 38 with abnormal left ventricular (LV) function [LV ejection fraction (LVEF) < 50%]. The autoEF results acquired using the HUD were independently compared with manually traced biplane Simpson’s rule measurements on cart-based systems to assess method agreement using intra-class correlation coefficient (ICC), linear regression analysis, and Bland–Altman analysis. The diagnostic accuracy for the detection of LVEF <50% was also calculated. Test–retest reliability of measured EF by the HUD was assessed by calculating the ICC and the minimal detectable change (MDC). The ICC, linear regression analysis, and Bland–Altman analysis revealed good agreement between autoEF and reference manual EF (ICC = 0.85; r = 0.87, P < 0.001; mean bias −1.42% with limits of agreement 14.5%, respectively). Detection of abnormal LV function (EF < 50%) by autoEF algorithm was feasible with sensitivity 90% (95% CI 75–97%), specificity 87% (95% CI 76–94%), PPV 81% (95% CI 66–91%), NPV 93% (95% CI 83–98%), and a total diagnostic accuracy of 88%. Test–retest reliability was excellent (ICC = 0.91, P < 0.001; r = 0.91, P < 0.001; mean difference ± SD: 0.54% ± 5.27%, P = 0.308) and MDC for LVEF measurement by autoEF was calculated at 4.38%.

Conclusion

Use of a novel HUD with AI-enabled capabilities provided similar LVEF results with those derived by manual biplane Simpson’s method on cart-based systems and shows clinical potential.
An efficient root transformation system for CRISPR/Cas9-based analyses of shoot–root communication in cucurbit crops
Authors: Geng Shouyu , Sohail Hamza , Cao Haishun , Sun Jingyu , Chen Zhi , Zhou Lijian , Wang Wenbo , Ye Runwen , Yang Li , Bie Zhilong
Published: January 2022

Cucurbit crops are suitable models for studying long-distance signaling in horticultural plants. Although thousands of substances are graft transmissible in cucurbits, functional studies have been hampered by the lack of efficient genetic transformation systems. Here, we report a convenient and efficient root transformation method for several cucurbit crops that will facilitate studies of functional genes and shoot–root crosstalk. We obtained healthy plants with completely transformed roots and non-transgenic shoots within 6 weeks. Furthermore, we combined this root transformation method with grafting, which allowed for gene manipulation in the rootstock. We validated our system by exploring salt tolerance mechanisms using a cucumber (Cucumis sativus)/pumpkin (Cucurbita moschata Duch.) (scion/rootstock) graft in which the sodium transporter gene High-affinity K+ transporter1 (CmoHKT1;1) was edited in the pumpkin rootstock and by overexpressing the pumpkin tonoplast Na+/H+ antiporter gene Sodium hydrogen exchanger4 (CmoNHX4) in cucumber roots.
BigMouth: development and maintenance of a successful dental data repository
Authors: Walji Muhammad F , Spallek Heiko , Kookal Krishna Kumar , Barrow Jane , Magnuson Britta , Tiwari Tamanna , Oyoyo Udochukwu , Brandt Michael , Howe Brian J , Anderson Gary C , White Joel M , Kalenderian Elsbeth
Published: January 2022

Few clinical datasets exist in dentistry to conduct secondary research. Hence, a novel dental data repository called BigMouth was developed, which has grown to include 11 academic institutions contributing Electronic Health Record data on over 4.5 million patients. The primary purpose for BigMouth is to serve as a high-quality resource for rapidly conducting oral health-related research. BigMouth allows for assessing the oral health status of a diverse US patient population; provides rationale and evidence for new oral health care delivery modes; and embraces the specific oral health research education mission. A data governance framework that encouraged data sharing while controlling contributed data was initially developed. This transformed over time into a mature framework, including a fee schedule for data requests and allowing access to researchers from noncontributing institutions. Adoption of BigMouth helps to foster new collaborations between clinical, epidemiological, statistical, and informatics experts and provides an additional venue for professional development.
The Effect of Soil Type and Moisture Level on the Development of Lucilia sericata (Diptera: Calliphoridae)
Authors: Kökdener Meltem , Şahin Yurtgan Müjgan
Published: January 2022

The present study aimed to determine the effects of the soil type and the moisture contents on the some life-history parameters of Lucilia sericata (Meigen, 1826) (Diptera: Calliphoridae). The larval and pupal survival, duration of development periods, and the weight of pupae and adult of L. sericata were examined at three different types of soil (clay, loamy, and sandy) with five moisture contents (0, 25, 50, 75, 100%). The post feeding L. sericata larvae were transferred to a plastic cup filled with soils with different moisture content, and all cups were kept at 27°C, 65% RH, and a photoperiod of 12:12 (L:D) h. In this article, the effects on some life-history parameters were compared with a two-way analysis of variance (ANOVA). Accordingly, the findings of this article indicate that moisture contents of soils and soil type have a significant effect on the development time of L. sericata. Furthermore, it has been found that larvae can survive on extremely wet substrates (75–100% humidity), although their development time is longer than other moisture content. Pupal and adult weight was significantly different among soil type and soil moisture. Our results provide a reference information for sufficient estimation of the effects of changes in moisture-related to soil type or climate on studies of forensic and biological control of L. sericata.
Expression Profiles of Immune Cells after Propofol or Sevoflurane Anesthesia for Colorectal Cancer Surgery: A Prospective Double-blind Randomized Trial
Authors: Oh Chung-Sik , Park Hyun-Jun , Piao Liyun , Sohn Kyo-Min , Koh Seong-Eun , Hwang Dae-Yong , Kim Seong-Hyop
Published: January 2022

Background

The antitumor effects of natural killer cells, helper T cells, and cytotoxic T cells after cancer surgery were reported previously. This study hypothesized that propofol-based anesthesia would have fewer harmful effects on immune cells than volatile anesthetics–based anesthesia during colorectal cancer surgery.

Methods

In total, 153 patients undergoing colorectal cancer surgery were randomized and included in the analysis. The primary outcome was the fraction of circulating natural killer cells over time in the propofol and sevoflurane groups. The fractions of circulating natural killer, type 1, type 17 helper T cells, and cytotoxic T cells were investigated. The fractions of CD39 and CD73 expressions on circulating regulatory T cells were investigated, along with the proportions of circulating neutrophils, lymphocytes, and monocytes.

Results

The fraction of circulating natural killer cells was not significantly different between the propofol and sevoflurane groups until 24 h postoperatively (20.4 ± 13.4% vs. 20.8 ± 11.3%, 17.9 ± 12.7% vs. 20.7 ± 11.9%, and 18.6 ± 11.6% vs. 21.3 ± 10.8% before anesthesia and after 1 and 24 h after anesthesia, respectively; difference [95% CI], –0.3 [–4.3 to 3.6], –2.8 [–6.8 to 1.1], and –2.6 [–6.2 to 1.0]; P = 0.863, P = 0.136, and P = 0.151 before anesthesia and after 1 and 24 h, respectively). The fractions of circulating type 1 and type 17 helper T cells, cytotoxic T cells, and CD39+ and CD73+ circulating regulatory T cells were not significantly different between the two groups. The neutrophil to lymphocyte ratio in both groups remained within the normal range and was not different between the groups.

Conclusions

Propofol-based anesthesia was not superior to sevoflurane-based anesthesia in terms of alleviating suppression of immune cells including natural killer cells and T lymphocytes during colorectal cancer surgery.

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The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) following acute myocardial infarction with cardiogenic shock (AMI-CS) is increasing, but the ability to predict favorable outcomes with support remains limited. We retrospectively reviewed all patients with AMI-CS supported with VA-ECMO between December 2008 and June 2018. One hundred twenty-six patients received VA-ECMO for AMI-CS during the study period; of these, 39 (31.0%) experienced ventricular recovery and were discharged while 87 (69.0%) did not recover, with 71 (56.3%) dying in the hospital and 16 (12.7%) surviving to discharge with either left ventricular assist device or heart transplant. TIMI 3 flow in culprit artery (OR, 4.01; 95% CI, 1.25–12.77; p = 0.02), serum lactate (OR, 0.89; 95% CI, 0.80–0.99; p = 0.04), and prompt revascularization (OR, 3.39; 95% CI, 1.18–9.81; p = 0.02) were independent predictors of ventricular recovery. Four variables emerged as independent predictors of in-hospital mortality and were used to create the AMI-ECMO Risk Score: age >70 years, creatinine >1.5 mg/dL, serum lactate > 4.0 mmol/L, and lack of TIMI 3 flow in culprit artery. In patients supported with VA-ECMO for AMI-CS, prompt, successful revascularization, and lower serum lactate were associated with ventricular recovery while younger age, lower serum lactate, and creatinine, and successful revascularization were associated with survival to discharge. The AMI-ECMO risk score is a simple tool that can help risk stratify patients with AMI-CS being considered for VA-ECMO support.
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Authors: Kamiura Rikuto , Mizuuchi Ryo , Ichihashi Norikazu
Published: January 2022

How the complexity of primitive self-replication molecules develops through Darwinian evolution remains a mystery with regards to the origin of life. Theoretical studies have proposed that coevolution with parasitic replicators increases network complexity by inducing inter-dependent replication. However, the feasibility of such complexification with biologically relevant molecules is still unknown owing to the lack of an experimental model. Here, we investigated the plausible complexification pathway of host–parasite replicators using both an experimental host–parasite RNA replication system and a theoretical model based on the experimental system. We first analyzed the parameter space that allows for sustainable replication in various replication networks ranging from a single molecule to three-member networks using computer simulation. The analysis shows that the most plausible complexification pathway from a single host replicator is the addition of a parasitic replicator, followed by the addition of a new host replicator that is resistant to the parasite. We also provide evidence that the pathway actually occurred in our previous evolutionary experiment. These results provide both a theoretical basis and experimental evidence that a single replicator spontaneously develops into multi-replicator networks through coevolution with parasitic replicators, which might be the first complexification step toward to the emergence of life.
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Authors: Capo Eric , Monchamp Marie‐Eve , Coolen Marco J. L. , Domaizon Isabelle , Armbrecht Linda , Bertilsson Stefan
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In‐depth knowledge about spatial and temporal variation in microbial diversity and function is needed for a better understanding of ecological and evolutionary responses to global change. In particular, the study of microbial ancient DNA preserved in sediment archives from lakes and oceans can help us to evaluate the responses of aquatic microbes in the past and make predictions about future biodiversity change in those ecosystems. Recent advances in molecular genetic methods applied to the analysis of historically deposited DNA in sediments have not only allowed the taxonomic identification of past aquatic microbial communities but also enabled tracing their evolution and adaptation to episodic disturbances and gradual environmental change. Nevertheless, some challenges remain for scientists to take full advantage of the rapidly developing field of paleo‐genetics, including the limited ability to detect rare taxa and reconstruct complete genomes for evolutionary studies. Here, we provide a brief review of some of the recent advances in the field of environmental paleomicrobiology and discuss remaining challenges related to the application of molecular genetic methods to study microbial diversity, ecology, and evolution in sediment archives. We anticipate that, in the near future, environmental paleomicrobiology will shed new light on the processes of microbial genome evolution and microbial ecosystem responses to quaternary environmental changes at an unprecedented level of detail. This information can, for example, aid geological reconstructions of biogeochemical cycles and predict ecosystem responses to environmental perturbations, including in the context of human‐induced global changes.
Time budgets and activity patterns of the southern gelada (Theropithecus gelada obscurus) in a human‐modified landscape, Wollo, Ethiopia
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Authors: Pan Yijun , Nicolazzo Joseph A.
Published: January 2022

The access of drugs into the central nervous system (CNS) is regulated by the blood–brain barrier (BBB) and blood–spinal cord barrier (BSCB). A large body of evidence supports perturbation of these barriers in neurodegenerative diseases, including Alzheimer's disease and Parkinson's disease. Modifications to the BBB and BSCB are also reported in amyotrophic lateral sclerosis (ALS), albeit these modifications have received less attention relative to those in other neurodegenerative diseases. Such alterations to the BBB and BSCB have the potential to impact on CNS exposure of drugs in ALS, modulating the effectiveness of drugs intended to reach the brain and the toxicity of drugs that are not intended to reach the brain. Given the clinical importance of these phenomena, this review will summarise reported modifications to the BBB and BSCB in ALS, discuss their impact on CNS drug exposure, and suggest further research directions so as to optimise medicine use in people with ALS.