bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel approach for detecting undercuts within surface textures generated by Electrochemical Jet Machining (ECJM)
Authors: Lazzini Gianmarco , Romoli Luca , Kunieda Masanori 
Published: March 2021

Abstract
The present study proposes a novel method for detecting micrometric undercuts (UCs) generated by electrochemical machining for the production of surfaces with tailored functionality. Two different algorithms for the detection of UCs based on two-dimensional topographic maps are tested. The first is a traditional approach based on definition of UCs in terms of surface orientation with respect to a reference direction. The second is an innovative alternative approach designed to reduce sensitivity to numerical effects that potentially lead to overestimation of the number of detected UCs. Electrochemical Jet Machining (ECJM) is used to texture SUS 316L specimens with the aim of producing a measurable surface with a representative number of micrometric UCs. Generated surface textures, comprising craters with diameters ranging from a few microns to tens of microns, are cross-sectioned and inspected with Scanning Electron Microscopy. The extracted profiles allow the novel method for detection of UCs to be efficiently tested and compared with the traditional approach. The number of UCs is found to decrease with increasing electrolyte jet scanning speed, while remarkable differences are revealed between the two calculation approaches at scanning speeds below 2 mm s−1.
Analyzing the mechanical and wear behavior of age hardening processed AZ31 magnesium composites
Authors: P Seenuvasaperumal , Elayaperumal A , Kumar Paskalis Sahaya Murphin , Arulvel S 
Published: March 2021

Abstract
The usage of AZ31 magnesium alloy has been limited in tribology applications, due to low hardness and poor wear resistance. In this connection, the age-hardening process is a promising heat treatment process for enhancing mechanical strength and wear resistance. Hence, the present work aims to analyze the effect of the age-hardening process on the microstructure, mechanical and wear behavior of AZ31 Magnesium-Calcium hexaboride composites (Mg composite). Here, dry sliding wear behavior was analyzed with different loads (10, 20, and 30 N) and sliding velocity (0.4, 0.6, and 0.8 m. s−1) for a constant sliding distance of 2000m. Age hardened composites exhibited a higher hardness and compressive strength which was due to the increased volume of the secondary precipitates (Mg17Al12 and Al8Mn5). The morphology study revealed that there is an exhibition of shear bands and brittle fracture for Age hardened composites. The remarkable wear rate reduction was achieved for age hardening processed composites due to the increased load-bearing capacity induced by the presence of a high volume of secondary precipitates. Delamination wear is the dominant wear mechanism for the composites and the delaminated craters increases with increasing the load condition. Further, the elemental mapping on the collected wear debris was also used to confirm the wear mechanism.
Nonlinear flexure mechanics of beams: stress gradient and nonlocal integral theory
Authors: Fazlali Mahdad , Moghtaderi Saeed H , Faghidian S Ali 
Published: March 2021

Abstract
In order to study the intrinsic size-effects, the stress gradient theory is implemented to a nano-scale beam model in nonlinear flexure. The nonlocal integral elasticity model is considered as a suitable counterpart to examine the softening behavior of nano-beams. Reissner variational principle is extended consistent with the stress gradient theory and applied to establish the differential, constitutive and boundary conditions of a nano-sized beam in nonlinear flexure. The nonlinear integro-differential and boundary conditions of inflected beams in the framework of the nonlocal integral elasticity are determined utilizing the total elastic strain energy formulation. A practical series solution approach in terms of Chebyshev polynomials is introduced to appropriately estimate the kinematic and kinetic field variables. A softening structural behavior is observed in the flexure of the stress gradient and the nonlocal beam in terms of the characteristic parameter and the smaller-is-softer phenomenon is, therefore, confirmed. The flexural response associated with the stress gradient theory is demonstrated to be in excellent agreement with the counterpart results of the nonlocal elasticity model equipped with the Helmholtz kernel function. The nonlocal elasticity theory endowed with the Error kernel function is illustrated to underestimate the flexural results of the stress gradient beam model. Detected numerical benchmark can be efficiently exploited for structural design and optimization of pioneering nano-engineering devices broadly utilized in advanced nano-electro-mechanical systems.
Research on the dynamic mechanical properties and constitutive model of metal rubber under impact loading
Authors: Zou Youchun , Xiong Chao , Yin Junhui , Cui Kaibo , Zhu Xiujie , Deng Huiyong , Song Shijun 
Published: March 2021

Abstract
The development of lightweight, impact-resistant and high energy dissipation materials is of great significance to reduce the hazards of explosions and impacts. Metal rubber (MR) has the characteristics of low density, high damping performance and high elasticity, which shows great potential in the field of protection. However, there are few studies on the dynamic mechanical response of MR under high-speed impact. A series of experiments were carried out to study the mechanical properties of MR. It is found that the deformation mechanism of the metal wire inside the MR determines the mechanical properties. Under quasi-static conditions, the stress-strain of MR includes an elastic stage, a softening stage and a hardening stage, and the stress-strain under high-speed impact includes an elastic stage, a softening stage and a failure stage. In addition, the smaller the wire diameter, the higher the load-bearing capacity of the MR. The damage characteristics of MR under high-speed impact are divided into expansion failure and compaction failure, which will affect mechanical performance in the failure stage. The calculated energy absorption and ideal energy absorption efficiency show that MR is a material with excellent energy absorption properties. The dynamic elastic modulus and dynamic peak stress of MR have strain rate effect and density effect. A constitutive model based on Sherwood-frost equation was established, which can precisely forecast the dynamic mechanical properties.
The impact of Fe/Mn loads on the surface property of rare earth mineral
Authors: Bai Yuze , Zhu JinHao , Luo HuiJuan , Wang ZhenFeng , Wu Wenfei , Zhang Kai 
Published: March 2021

AbstractAfter using the mixed acid system to modify the surface of rare earth minerals, two transition metals (Fe and Mn) are loaded on the surface of the rare earth minerals by hydrothermal method to improve the NH3-SCR (Selective catalytic reduction) activity. In this paper, a variety of characterization means like SEM, XRD, BET, XPS, H2-TPR (Temperature-programmed reduction), NH3-TPD (Temperature-programmed desorption) and NO-TPD are used to study and analyze the surface properties of rare earth minerals before and after loading transition metals. Its catalytic performance was further measured in a simulated flue gas installation. The results show that the active elements on the surface of rare earth minerals after loading transition metals are mainly oxides. The specific surface area of rare earth minerals is effectively improved, the crystallinity of the active material is reduced, and the element distribution is more uniform. In addition, a composite structure of Fe-Ce and Mn-Ce is formed on the surface of rare earth minerals, and the oxygen vacancies and adsorption sites on the surface of the minerals are significantly improved. The NOXconversion rate for Fe-loaded mineral catalysts reached 89.1% at 300 ℃. The NOXconversion rate for Mn-loaded mineral catalysts reached 92.3% at 250 ℃. Generally speaking, the NH3-SCR activity of rare earth mineral can be improved by loading transition metals (Fe and Mn).
Sustainable paths to a circular economy: reusing aged Li-ion FePO4 cathodes within Na-ion cells
Authors: Gucciardi Emanuele , Galceran Montserrat , Bustinza Ainhoa , Bekaert Emilie , Casas-Cabanas Montse 
Published: March 2021

Abstract
Responsible disposal and recycling are essential for the sustainability of the battery market, which has been exponentially growing in the past few years. Under such a scenario, the recycling of materials of less economic value, but environmentally much more sustainable like LiFePO4, represents an economic challenge. In this paper an approach to recover used FePO4 electrodes from calendar aged Lithium-ion (Li-ion) batteries and their reuse in Sodium-ion (Na-ion) cells is proposed. The electrochemical performances of the Na-ion cell are shown to be comparable with previously reported values and, since the electrode can retain the original microstructure and distribution, electrode processing can be avoided. A proof of concept of a NaFePO4//hard carbon full cell using a very high positive electrode loading optimized for Li-ion batteries (≈14 mg cm−2) is shown.
Rhinoplasty in the Older Adult
Authors: Khetpal Sumun , Gowda Arvind U , Parsaei Yassmin , Mozaffari Mohammad Ali , Dinis Jacob , Lopez Joseph , Steinbacher Derek 
Published: March 2021

Abstract

Background
Rhinoplasty in older adults requires unique consideration of the aging nose.

Objectives
The purpose of this study was to systematically review the literature pertaining to rhinoplasty in the aging population, review the senior author’s experience, and describe techniques aimed at addressing age-related features. It was hypothesized that consistent age-related nasal dysmorphology is described in the literature and standard rhinoplasty techniques may effectively address these changes. Furthermore, it was hypothesized that rhinoplasty is more commonly performed for posttraumatic and functional indications than for aesthetic reasons.

Methods
A literature review including publications describing rhinoplasty in patients over 55 years old was conducted. Additionally, a retrospective review of the senior author’s cases was performed. Pre- and postoperative photographs were used to compare anthropometric changes. Demographic factors, surgical indications, and operative details were collected.

Results
Nine articles met the study criteria. Manifestations of the aging nose included soft tissue atrophy, bony fragility and resorption, tip ptosis, internal and external valve collapse, and worsening dorsal hump. Twenty-seven patients were included in this institutional review. Primary indication for rhinoplasty was posttraumatic deformity in 17 (63%) patients and nasal obstructive symptoms in 10 (37%) patients. Tip refinement and ptosis were addressed through tip grafts (70%), columellar struts (26%), and caudal septal extension grafts (67%). Nasal obstruction was relieved through septoplasty (96%), turbinate ablation (85%), and spreader grafts (70%).

Conclusions
This study presents a systematic review of rhinoplasty in the older adult as well as a retrospective review of the senior author’s patients. Unique considerations specific to this population should be integrated into treatment planning.

Level of Evidence: 4
Impact of COVID-19 on surgical emergencies: nationwide analysis
Authors: Lazzati A , Raphael Rousseau M , Bartier S , Dabi Y , Challine A , Haddad B , Herta N , Souied E , Ortala M , Epaud S , Masson M , Salaün-Penquer N , Coste A , Jung C 
Published: March 2021

Abstract

Background
The COVID-19 pandemic has had a major impact on healthcare in many countries. This study assessed the effect of a nationwide lockdown in France on admissions for acute surgical conditions and the subsequent impact on postoperative mortality.

Methods
This was an observational analytical study, evaluating data from a national discharge database that collected all discharge reports from any hospital in France. All adult patients admitted through the emergency department and requiring a surgical treatment between 17 March and 11 May 2020, and the equivalent period in 2019 were included. The primary outcome was the change in number of hospital admissions for acute surgical conditions. Mortality was assessed in the matched population, and stratified by region.

Results
During the lockdown period, 57 589 consecutive patients were admitted for acute surgical conditions, representing a decrease of 20.9 per cent compared with the 2019 cohort. Significant differences between regions were observed: the decrease was 15.6, 17.2, and 26.8 per cent for low-, intermediate- and high-prevalence regions respectively. The mortality rate was 1.92 per cent during the lockdown period and 1.81 per cent in 2019. In high-prevalence zones, mortality was significantly increased (odds ratio 1.22, 95 per cent c.i. 1.06 to 1.40).

Conclusion
A marked decrease in hospital admissions for surgical emergencies was observed during the lockdown period, with increased mortality in regions with a higher prevalence of COVID-19 infection. Health authorities should use these findings to preserve quality of care and deliver appropriate messages to the population.
Acute Page kidney after angioplasty in kidney transplant allografts
Authors: Canllavi Elizabeth , Teigell Julio , Trujillo Hernando , Gutiérrez Eduardo , Sánchez Angel , Miranda-Utrera Natalia , Morales Enrique 
Published: March 2021

Abstract
Acute Page kidney (APK) in kidney transplantation is a rare entity often related to interventional techniques. Percutaneous angioplasty remains an exceptional cause of APK. Herein we describe the clinical course and outcome of APK following percutaneous angioplasty for transplant renal artery stenosis in four kidney transplant recipients, where external compression of the graft was caused by subcapsular haematomas. All patients were treated with surgical drainage, after which two cases recovered baseline kidney function, one developed advanced chronic kidney disease and one remained dialysis-dependent. To our knowledge, the present series is the largest to describe APK in kidney allografts after percutaneous angioplasty.
Learning Saliency-Aware Correlation Filters for Visual Tracking
Authors: Wang Yanbo , Wang Fasheng , Wang Chang , Sun Fuming , He Jianjun 
Published: March 2021

Abstract
Recently, visual object tracking has become a hot topic in computer vision community owing to its extensive applications and fundamental research significance. Many researchers have paid attention to the discriminative correlation filter (DCF) due to its excellent tracking performance. The background-aware CF (BACF) is developed to handle the inevitable boundary effects of DCFs that shows superior performance compared with other CF-based trackers. However, BACF has a poor occlusion handling ability. To overcome this defect, we propose a saliency-aware CF tracking (SACF) model. In SACF, a saliency map of the target is introduced on CFs to strengthen the ability to extract the target from a complex background. Meanwhile, to adjust to the rapid variation of the target appearance, we adaptively modify the learning rate of the filter template using adaptive learning rate. By incorporating the saliency map into the BACF objective function and adaptive learning rate adjustment, the robustness and accuracy of the tracker are boosted significantly. Extensive experiments validate that our method can efficaciously solve the occlusion problem and achieves state-of-the-art performance in terms of accuracy and speed on standard benchmarks, i.e. OTB-2013, OTB-2015 and LaSOT. Compared with other state-of-the-art CF tracking methods, the proposed method is competitive considering accuracy and success rate.
The Surplus Approach, Institutions, And Economic Formations
Authors: Cesaratto Sergio , Di Bucchianico Stefano 
Published: March 2021

AbstractThe paper develops Pierangelo Garegnani’s notion of the ‘core’ of the classical theory of distribution to propose a wider integration of the concept of social surplus and institutions into economic thinking. Its main tenet is that the social surplus does not exist independently of the institutions (or social order) that oversee its production and distribution, starting from those that prevail in the sphere of production. In this sense, we supplement the surplus approach with important insights not only from the Polanyian approach, from economic archaeology and anthropology, but also from Sraffian authors and Sraffa’s manuscripts. Taking inspiration from Garegnani, this work is offered as a prelude to the design of different economic ‘cores’ for different stylized economic formations.
Exponential discounting in security games of timing
Authors: Merlevede Jonathan , Johnson Benjamin , Grossklags Jens , Holvoet Tom 
Published: March 2021

Abstract
Strategic game models of defense against stealthy, targeted attacks that cannot be prevented but only mitigated are the subject of a significant body of recent research, often in the context of advanced persistent threats (APTs). In these game models, the timing of attack and defense moves plays a central role. A common assumption, in this literature, is that players are indifferent between costs and gains now and those in the distant future, which conflicts with the widely accepted treatment of intertemporal choice across economic contexts. This article investigates the significance of this assumption by studying changes in optimal player behavior when introducing time discounting. Specifically, we adapt a popular model in the games of timing literature, the FlipIt model, by allowing for exponential discounting of gains and costs over time. We investigate changes of best responses and the location of Nash equilibria through analysis of two well-known classes of player strategies: those where the time between players’ moves is constant, and a second class where the time between players’ moves is stochastic and exponentially distributed. By introducing time discounting in the framework of games of timing, we increase its level of realism as well as applicability to organizational security management, which is in dire need of sound theoretic work to respond to sophisticated, stealthy attack vectors.
Association between age and neurological outcomes in out-of-hospital cardiac arrest patients resuscitated with extracorporeal cardiopulmonary resuscitation: a nationwide multicentre observational study
Authors: Miyamoto Yuki , Matsuyama Tasuku , Goto Tadahiro , Ohbe Hiroyuki , Kitamura Tetsuhisa , Yasunaga Hideo , Ohta Bon 
Published: March 2021

AbstractAimsLittle is known about the difference in outcomes between young and old patients who received extracorporeal cardiopulmonary resuscitation (ECPR) for out-of-hospital cardiac arrest (OHCA). Therefore, we aimed to investigate the differences in outcomes between those aged ≥75 years and &lt;75 years who experienced OHCA and were resuscitated with ECPR.Methods and resultsWe performed a secondary analysis of a nationwide prospective cohort study using the Japanese Association for Acute Medicine OHCA registry. We identified patients aged ≥18 years with OHCA who received ECPR. The patients were classified into three age groups (18–59 years, 60–74 years, and ≥75 years). The primary outcome was a 1-month neurological outcome. To examine the association between age and 1-month neurological outcome, we performed logistic regression analyses fitted with generalized estimating equations. From 2014 to 2017, we identified 875 OHCA patients aged ≥18 years who received ECPR. The proportion of patients who survived with favourable neurological outcome in the patients aged 18–59 years, 60–74 years, and ≥75 years were 15% (64/434), 8.9% (29/326), and 1.7% (2/115), respectively. In the multivariable analysis, compared with the age of 18–59 years, the proportions of favourable neurological outcomes were significantly lower in patients aged 60–74 years [adjusted odds ratio (OR), 0.44; 95% confidence interval (CI), 0.32–0.61] and those aged ≥75 years (adjusted OR, 0.26; 95% CI, 0.11–0.59).ConclusionAdvanced age (age ≥75 years in particular) was significantly associated with poor neurological outcomes in patients with OHCA who received ECPR.
An overview ofSalmonella entericametal homeostasis pathways during infection
Authors: Cunrath Olivier , Palmer Jacob D 
Published: March 2021

ABSTRACTNutritional immunity is a powerful strategy at the core of the battlefield between host survival and pathogen proliferation. A host can prevent pathogens from accessing biological metals such as Mg, Fe, Zn, Mn, Cu, Co or Ni, or actively intoxicate them with metal overload. While the importance of metal homeostasis for the enteric pathogen Salmonella enterica Typhimurium was demonstrated many decades ago, inconsistent results across various mouse models, diverse Salmonella genotypes, and differing infection routes challenge aspects of our understanding of this phenomenon. With expanding access to CRISPR-Cas9 for host genome manipulation, it is now pertinent to re-visit past results in the context of specific mouse models, identify gaps and incongruities in current knowledge landscape of Salmonella homeostasis, and recommend a straight path forward towards a more universal understanding of this historic host–microbe relationship.
Metabarcoding analysis suggests that flexible food web interactions in the eukaryotic plankton community are more common than specific predator–prey relationships at Helgoland Roads, North Sea
Authors: Käse Laura , Metfies Katja , Kraberg Alexandra C , Neuhaus Stefan , Meunier Cédric L , Wiltshire Karen H , Boersma Maarten 
Published: March 2021

Abstract
Various field studies on plankton dynamics have broadened our understanding of seasonal succession patterns. Additionally, laboratory experiments have described consumers ranging from generalists to selective grazers. While both approaches can give us a good understanding of the ecosystem and its dynamics, drawbacks in identification and a limited coverage of the ecosystem have left open questions on the generality of previous results. Using an integrative approach, we investigated water samples taken at Helgoland Roads by metabarcoding to describe seasonal succession patterns of the whole plankton community. By use of network analysis, we also tried to identify predator–prey dynamics. Our data set depicted the strong seasonality typically found for temperate waters. Despite a stable background community surviving strong fluctuations, small and abrupt changes, such as pronounced blooms and random appearance of autotrophs, cause seasons to be quite different in an inter-year comparison. Main consumers were copepods, ciliates, and dinoflagellates, of which the latter were most abundant. Furthermore, our results suggest that zooplankton predators might favour specific prey during certain time periods but seem to be quite opportunistic otherwise throughout the year. The variability and potential for many different relationships in the plankton community might be an indicator of resilience in the system.