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The performance of any meta-heuristic algorithm depends highly on the setting of dependent parameters of the algorithm. Different parameter settings for an algorithm may lead to different outcomes. An optimal parameter setting should support the algorithm to achieve a convincing level of performance or optimality in solving a range of optimization problems. This paper presents a novel enhancement method for the salp swarm algorithm (SSA), referred to as enhanced SSA (ESSA). In this ESSA, the following enhancements are proposed: First, a new position updating process was proposed. Second, a new dominant parameter different from that used in SSA was presented in ESSA. Third, a novel lifetime convergence method for tuning the dominant parameter of ESSA using ESSA itself was presented to enhance the convergence performance of ESSA. These enhancements to SSA were proposed in ESSA to augment its exploration and exploitation capabilities to achieve optimal global solutions, in which the dominant parameter of ESSA is updated iteratively through the evolutionary process of ESSA so that the positions of the search agents of ESSA are updated accordingly. These improvements on SSA through ESSA support it to avoid premature convergence and efficiently find the global optimum solution for many real-world optimization problems. The efficiency of ESSA was verified by testing it on several basic benchmark test functions. A comparative performance analysis between ESSA and other meta-heuristic algorithms was performed. Statistical test methods have evidenced the significance of the results obtained by ESSA. The efficacy of ESSA in solving real-world problems and applications is also demonstrated with five well-known engineering design problems and two real industrial problems. The comparative results show that ESSA imparts better performance and convergence than SSA and other meta-heuristic algorithms.

The Paraná Basin, Brazil and the Chaco-Paraná Basin, Uruguay both contain sedimentary records that are critical to reconstructing late Paleozoic ice centers in central Gondwana. The orientations of subglacial landforms and glaciotectonic structures suggest that late Paleozoic glacial deposits in the eastern Chaco-Paraná Basin and the southernmost Paraná Basin are genetically related, as they were likely glaciated by the same ice center. However, the location and extent of the ice center responsible for depositing these sediments are unclear. Furthermore, changes in sediment dispersal patterns between glacial, inter-glacial, and post-glacial intervals are not understood for this region of Gondwana. Therefore, this study utilized U–Pb detrital zircon geochronology to assess the provenance of glacial and post-glacial sediments from the eastern Chaco-Paraná Basin (San Gregorio, Cerro Pelado, Tres Islas Formations) and the southernmost Paraná Basin (Itararé Group). Results show dominant age peaks at 520–555 Ma, 625 Ma, 750–780 Ma, and 900–1000 Ma in all samples from the eastern Chaco-Paraná Basin. These zircons are interpreted to have been derived from sources in the Cuchilla Dionisio Terrane and Punta del Este Terrane in southeastern Uruguay, and possibly the Namaqua Belt in southern Namibia. Another important source was likely Devonian sedimentary rocks of the Durazno Group in central/eastern Uruguay. Meanwhile, a sample of the glaciogenic Itararé Group from the southernmost Paraná Basin contains a different detrital zircon signature with peaks at 580 Ma, 780 Ma, 2110 Ma, and 2500 Ma that closely resembles underlying sedimentary and meta-sedimentary rocks of the Precambrian/Cambrian Camaquã Basin. Detrital zircon ages in the glacial and post-glacial sediments indicate that local sources were dominant. In contrast, zircon ages from relatively ice-distal glaciomarine intervals in the Chaco-Paraná Basin reflect more distal sources to the east and southeast, which indicates a larger drainage catchment opened when glaciers retreated and/or the zone of maximum subglacial erosion shifted. Although most zircon ages in the Chaco-Paraná Basin can be attributed to Uruguayan sources, results support the hypothesis that glaciers emanated from southern Namibia and southeast Uruguay into the Chaco-Paraná Basin. From there, ice flowed northwest into the Paraná Basin and then receded back towards Africa as the paleoclimate warmed. The detrital zircon inventory in our study region is distinct from the eastern Paraná Basin, suggesting at least two unique African source regions for glaciers that deposited sediments in the Paraná and Chaco-Paraná Basins. © 2020 Elsevier Ltd

In this letter, measurements of the shared momentum fraction (zg) and the groomed jet radius (Rg), as defined in the SoftDrop algorithm, are reported in p+p collisions at s=200 GeV collected by the STAR experiment. These substructure observables are differentially measured for jets of varying resolution parameters from R=0.2−0.6 in the transverse momentum range 15<pT,jet<60 GeV/c. These studies show that, in the pT,jet range accessible at s=200 GeV and with increasing jet resolution parameter and jet transverse momentum, the zg distribution asymptotically converges to the DGLAP splitting kernel for a quark radiating a gluon. The groomed jet radius measurements reflect a momentum-dependent narrowing of the jet structure for jets of a given resolution parameter, i.e., the larger the pT,jet, the narrower the first splitting. For the first time, these fully corrected measurements are compared to Monte Carlo generators with leading order QCD matrix elements and leading log in the parton shower, and to state-of-the-art theoretical calculations at next-to-leading-log accuracy. We observe that PYTHIA 6 with parameters tuned to reproduce RHIC measurements is able to quantitatively describe data, whereas PYTHIA 8 and HERWIG 7, tuned to reproduce LHC data, are unable to provide a simultaneous description of both zg and Rg, resulting in opportunities for fine parameter tuning of these models for p+p collisions at RHIC energies. We also find that the theoretical calculations without non-perturbative corrections are able to qualitatively describe the trend in data for jets of large resolution parameters at high pT,jet, but fail at small jet resolution parameters and low jet transverse momenta.

Envisioning societal futures for systemic low carbon transition is key to supporting the emergence of new configurations of the energy system. Such visions or ‘imaginaries’ facilitate wider societal support for system change. Given the urgency of the decarbonisation agenda, societal understandings of transitions processes and community ideas and visions about pathways for change assume a key role. The paper addresses an important gap in knowledge of place-based visions of energy system transition by soliciting views of community residents through a survey instrument, on what their perspectives on energy transition are. A case-study of Liverpool UK is presented, conducted as part of the EU Horizon 2020 ENTRUST project. Through a cluster analysis approach of study respondent perspectives, this study identities 4 distinct energy visions: (1) Community Affordability; (2) The Centre Ground; (3) Security First; and (4) Green Affordability. Identified visions present different perspectives on how energy is framed, with each vision characterised by distinct preferences on the extent to which stakeholder groups may influence the energy system as well as different views on the role of specific energy generation methods. Further, visions differ on the role of different actors and institutions in the energy transition. Identified energy visions provide insight into the ways in which grassroots communities consider how the energy system should transition in the coming years. The study contributes to understanding of spatially-situated and socially differentiated views of energy system transition, providing insight into contrasting viewpoints on current and future energy system priorities of residents of Liverpool, UK. © 2020 Elsevier Ltd

In August 2018, Swedish teenager Greta Thunberg started to strike from school on Fridays to protest against a lack of action on the climate crisis. Her actions sparked a historically large youth movement, leading to a series of school strikes across the world. Over the course of one week in September 2019, striking school children, students and other grassroots movements, such as Extinction Rebellion, called for everyone to participate in a global Climate Strike. This paper is based on comparative research with climate protesters in six cities: Brighton and London (United Kingdom), Montreal (Canada), New Haven and New York (USA), and Stavanger (Norway). Based on original interviews with 64 protesters, the study examines their knowledge, emotions, motivations, and actions in relation to climate change, including any lifestyle changes they have undertaken before or after their protests. Our findings show that protesters have varying degrees of knowledge about climate change, and have taken a range of actions in their own lives to address climate change. They also manifest a wide spectrum of emotions about climate change, and different motivations for taking part in climate strikes. These features are under-studied and dynamically evolving at the present conjuncture. On this basis, we call for expanded academic attention to human, emotional, epistemic, and seemingly mundane aspects of climate protests, their structural tendencies and relational expressions, and the implications for our ability to address underlying drivers. © 2020 Elsevier Ltd

Flow harmonics (vn) of the Fourier expansion for the azimuthal distributions of hadrons are commonly employed to quantify the azimuthal anisotropy of particle production relative to the collision symmetry planes. While lower order Fourier coefficients (v2 and v3) are more directly related to the corresponding eccentricities of the initial state, the higher-order flow harmonics (vn>3) can be induced by a mode-coupled response to the lower-order anisotropies, in addition to a linear response to the same-order anisotropies. These higher-order flow harmonics and their linear and mode-coupled contributions can be used to more precisely constrain the initial conditions and the transport properties of the medium in theoretical models. The multiparticle azimuthal cumulant method is used to measure the linear and mode-coupled contributions in the higher-order anisotropic flow, the mode-coupled response coefficients, and the correlations of the event plane angles for charged particles as functions of centrality and transverse momentum in Au+Au collisions at nucleon-nucleon center-of-mass energy sNN= 200 GeV. The results are compared to similar LHC measurements as well as to several viscous hydrodynamic calculations with varying initial conditions.

We report results on the total and elastic cross sections in proton-proton collisions at s=200 GeV obtained with the Roman Pot setup of the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The elastic differential cross section was measured in the squared four-momentum transfer range 0.045≤−t≤0.135 GeV2. The value of the exponential slope parameter B of the elastic differential cross section dσ/dt∼e−Bt in the measured −t range was found to be B=14.32±0.09(stat.)−0.28+0.13(syst.) GeV−2. The total cross section σtot, obtained from extrapolation of the dσ/dt to the optical point at −t=0, is σtot=54.67±0.21(stat.)−1.38+1.28(syst.) mb. We also present the values of the elastic cross section σel=10.85±0.03(stat.)−0.41+0.49(syst.) mb, the elastic cross section integrated within the STAR t-range σeldet=4.05±0.01(stat.)−0.17+0.18(syst.) mb, and the inelastic cross section σinel=43.82±0.21(stat.)−1.44+1.37(syst.) mb. The results are compared with the world data.

There is substantial difficulty with effectively, and meaningfully, engaging the public with community-based sustainability projects as a method to facilitate sustainable lifestyles. Individuals engage with community projects in numerous ways: cognitively (knowledge), affectively (emotions), and behaviourally (actions). One prevalent consideration that individuals consider is other peoples’ (lack of) engagement; given that the success of community-based approaches addressing climate change is dependent upon the actions, and participation, of all local residents. Findings from focus groups in seven urban communities in the UK are presented that illustrate clear elements of ‘Othering’ as part of individual engagements with community-based sustainability projects. Primarily, there is substantial consideration towards what other people within the community know, feel, and do to engage with community-based projects. Residents distinguish themselves in opposition to those they view as engaging, and not engaging, in the same way as themselves and indicate the need for equitable participation amongst all residents. These considerations have the potential to project particular barriers on wider community engagement if left to develop, cause tension, and are not resolved. Implications for participatory strategies to meaningfully and effectively engage individuals with community-based sustainability and transformational change are outlined. Insights into how considerations of ‘Othering’ can be overcome so as not to cause negative engagements with other residents and attempts to live sustainably as part of a community approach are illustrated. © 2020

In this article, I attempt to describe how language is reified, using the call center as an extended example. I take up recent debates regarding language and economic value, attempting to disentangle a by now substantial series of arguments about language and commodification. The theoretical core of the paper is drawn from the work of Georg Lukács, who provided the account of reification that was at the root of twentieth century critical theory. Following Lukács, I argue that what is indispensable in the process of reification is both a “contemplative stance” in relation to economic laws and the presence of “special partial systems” within the production process of commodities. These are particularly important considerations for what I refer to as the one-sided rationalization of language that occurs in call centers in particular, but also on a more widespread social basis. © 2020 Elsevier Ltd

The United States is in the midst of an opioid epidemic. The numbers of opioid-related deaths have been steadily climbing, magnifying the need for innovative intervention. Stigma is a set of preconceived, negative assumptions about a patient population or group. Stigma is a known deterrent to communication and the delivery of healthcare. Nurses serve as a primary contact for many marginalized patients within the healthcare system. The purpose of this scoping review is to gather known data on the use of educational interventions with nursing students to reduce stigmatizing tendencies. Inclusion criteria constituted an educational intervention involving student nurses and an effort to reduce stigmatizing attitudes toward patients who misuse opioids. The intervention must have taken place in an institute of higher learning between the years of 2003 and 2018. Exclusion criteria included community-wide studies. A single study was identified addressing nursing student reduction of stigmatization of the individual who uses opioids, and so, the search was expanded to include any student nursing intervention developed to reduce stigma toward any marginalized population. The following electronic databases were utilized in the search process: Cumulative Index of Nursing and Allied Health Literature, Google Scholar, Journal Storage, Microsoft Academic, and ScienceDirect. Reference pages of selected or related articles were reviewed in an attempt to identify additional pertinent literature through citation mapping. Fifteen studies were identified, each of which utilized a variable methodology for stigma reduction with varying levels of success. © Lippincott Williams & Wilkins.

With the tremendous growth in online classes and programs at institutions of higher education, conflicting claims are increasingly being made on media and blog sites about the personality types that are compatible with this new learning format. The relations between the Five Factor Model of Personality (FFM) and linguistic styles with measures of academic performance in fully online asynchronous classes were examined. Consistent with findings based on research in face-to-face classes, Conscientiousness, Openness to Experience, and Analytic Thinking were associated with academic success. There was no support for the views propagated on the internet that extraversion, introversion, or anxiety hinder or foster online learning. The most robust predictor of academic performance throughout the semester, independent of the personality variables, was the number of words students contributed to the online discussions. These finding are interpreted within the Community of Inquiry framework (CoI; Garrison, 2003) and future lines of research are suggested. © 2020 Elsevier Inc.

The recent explosion of wearable technology and the associated concerns prompted the International Federation of Sports Medicine (FIMS) to create a quality assurance standard for wearable devices, which provides commissioned testing of marketing claims and endorsement of commercial wearables that test favorably. An open forum as announced in the conference advertising was held at the Annual Meeting of the New England Regional Chapter of the American College of Sports Medicine (NEACSM) November 7 to 8, 2019, in Providence, Rhode Island, USA for attending NEACSM members to voice their input on the process. Herein, we report the proceedings. The round table participants perceived the quality assurance standard to be important, but identified some practical process challenges that included the broad scope and complexity of the device universe, the need for a multiphase testing pathway, and the associated fees for product evaluation. The participants also supported the evaluation of device data analysis, behavioral influences, and user experience in the overall evaluation. Looking forward, the FIMS quality assurance standard faces the challenge of balancing these broader perspectives with practical constraints of budget, facilities, time, and human resources. © 2020 by the American College of Sports Medicine.

Vineyards in the New England region of the USA were surveyed for the occurrence of grapevine viruses. A total of ten vineyards were visited and 62 composite samples of leaves with the petioles were collected from symptomatic grapevines (Vitis spp.). All of the samples were assayed by double-antibody sandwich enzyme-linked immunosorbent assays (DAS-ELISA) using antibodies specific for four major grapevine leafroll-associated viruses (GLRaV-1, GLRaV-2, GLRaV-3, and GLRaV-4), grapevine fanleaf virus (GFLV), tobacco ringspot virus (TRSV), and tomato ringspot virus (ToRSV). Positive ELISA samples were further tested by reverse transcription polymerase chain reaction (RT-PCR) with primers specific for each of the viruses to confirm the ELISA results. Twenty-two samples were infected with at least one of the viruses tested. GLRaV-3 (24.19%) was the most prevalent virus detected followed by GLRaV-1 (12.90%), ToRSV (3.23%), and GLRaV-2 and TRSV (1.61%). This is the first study reporting on the presence of grapevine viruses in New England. Extensive surveys need to be conducted to evaluate the prevalence and economic impact of these viruses on New England vineyards. © 2020 Elsevier Ltd

Economists have long been intrigued by an influential literature in psychology positing that monetary pay lowers performance on enjoyable tasks by crowding out agents’ intrinsic interest in them. But typical experiments in this literature do not report a full set of performance metrics, which might reveal conflicting evidence on crowding out. Further, they may suffer from confounds. To evaluate these issues, we review over 100 prior tests and run a field experiment building on the canonical two-session test for crowding out wherein agents receive pay for an interesting activity in session 1 that is withdrawn unexpectedly in session 2. We test whether pay harms performance using a comprehensive set of performance measures, and if so, whether unmet pay expectations might also contribute to this decline. Our results on output, productivity and quits are most consistent with a standard economics model than with a crowding-out one. Additional, though more speculative, evidence suggests that unmet pay expectations may harm output quality. © 2020 The President and Fellows of Harvard College and the Massachusetts Institute of Technology.

Social workers have always worked with and within uncertainties in practice, but the COVID-19 pandemic is amplifying the frequency and degree of uncertainty across ecological levels. Social workers need enhanced capacity to work with these uncertainties and the impact on individual and collective wellbeing. The RE/UN/DIScover heuristic guides social workers’ responses to the wide range of practice uncertainties experienced in the moment and over time. Drawing on understandings of embodied wellbeing from interpersonal neurobiology and the power relations manifest in intersectional positionality, RE/UN/DIScover offers embodied, iterative practices to access the wealth of capabilities within self and others. IMPLICATIONS Disruptions and uncertainties connected with pandemics, economic recessions, continued systemic injustices and other human-made problems can challenge social workers and impact the wellbeing of individuals and communities. Heuristics are guides that sort, order, and inform decisions and actions. The RE/UN/DIScover heuristic uses knowledge about embodied wellbeing and various forms of power to guide social workers. RE/UN/DIScover offers social workers practices to use with uncertainties both in the moment and over time. © 2020 Australian Association of Social Workers.

Meta-heuristic search algorithms were successfully used to solve a variety of problems in engineering, science, business, and finance. Meta-heuristic algorithms share common features since they are population-based approaches that use a set of tuning parameters to evolve new solutions based on the natural behavior of creatures. In this paper, we present a novel nature-inspired search optimization algorithm called the capuchin search algorithm (CapSA) for solving constrained and global optimization problems. The key inspiration of CapSA is the dynamic behavior of capuchin monkeys.The basic optimization characteristics of this new algorithm are designed by modeling the social actions of capuchins during wandering and foraging over trees and riverbanks in forests while searching for food sources. Some of the common behaviors of capuchins during foraging that are implemented in this algorithm are leaping, swinging, and climbing. Jumping is an effective mechanism used by capuchins to jump from tree to tree. The other foraging mechanisms exercised by capuchins, known as swinging and climbing, allow the capuchins to move small distances over trees, tree branches, and the extremities of the tree branches. These locomotion mechanisms eventually lead to feasible solutions of global optimization problems. The proposed algorithm is benchmarked on 23 well-known benchmark functions, as well as solving several challenging and computationally costly engineering problems. A broad comparative study is conducted to demonstrate the efficacy of CapSA over several prominent meta-heuristic algorithms in terms of optimization precision and statistical test analysis. Overall results show that CapSA renders more precise solutions with a high convergence rate compared to competitive meta-heuristic methods. © 2020, Springer-Verlag London Ltd., part of Springer Nature.

This paper presents a study on 80 countries that evaluates the socioeconomic factors in containing the spread and mortality of COVID-19. Our results show that the long-term social factors such as lower personal freedom, better education in science, and past coronavirus outbreak experience are more effective than the economic factors such as higher healthcare-associated factors per 1000 population and larger GDP. However, using GDP per capita as the instrumental variable, we also find that the richer countries with a high degree of personal freedom have a higher number of infection or death cases per million population because they would be less likely to adhere to and implement the policy of the movement restrictions to restrict their access to goods and services. © 2020 Informa UK Limited, trading as Taylor & Francis Group.