bluuebunny/crossref_metadata_2025 huggingface dataset:
Advanced separation technologies for pre-concentration of metal ores and the additional process control
Authors: Kolacz Jacek
Published: August 2021

A new sensor based sorting system has been developed at Comex, based on complex image analysis. The sorting system employs different images generated by visible light and X-ray to provide maximal information about processed particles. Application of X-ray makes it possible to analyse the internal structure of the particles, which provides a 2D image with the valuable information. The advanced system for the texture and the pattern recognition is applied to analyse these images simultaneously, to provide the required identification of the particles for efficient separation. The paper describes a number of tests during sorting of Cu-Zn-Sn ores with high separation efficiency. As an example, the Cu content is enriched from 0.4% to 1.25% and the Zn content is increased from 0.83% to 2.24%. In addition, the performance of the X-ray sorting system is described for enrichment of Zn-Pb ore and compared with the heavy media separation technology. Simplifying the pre- concentration through the use of the sorting technology can significantly reduce the cost of these operations. Finally, the operating data from the sorting system have been analysed regarding a potential use for controlling the plant operation. This can bring the new tools for control strategies for the complex processing plants.
The influence of lead on concentrates quality produced in KGHM Polska Miedz concentrator plants
Authors: Pawlos Witold , Krzemińska Małgorzata
Published: August 2021

The behaviour of lead compounds present in feed of beneficiation process has been discussed. Changeability of copper and lead content in feed during last decades has been described. Galena was pointed as a major source of lead and the beneficiation kinetic of this mineral was presented comparing with other sulphides, including copper sulphides. Significant amount of galena together with its very good concentrating properties crucially effect on quality of concentrates produced in Lubin concentrator plant.
Research on the Possibility of Sorting Application for Separation of Shale and/or Gangue from the Feed of Rudna Concentrator
Authors: Grotowski Andrzej , Witecki Kajetan
Published: August 2021

Shale, which occurs in the copper ore deposits belonging to KGHM Polska Miedź S.A., is the reason for a number of difficulties, at the stage of not only processing but also smelting. Gangue, in turn, getting in a feed during mining is a useless load of a concentrator and also contributes to lowering concentrating indexes. Its content in a feed is being evaluated at 15-30%. The multiple attempts to solve those issues by the methods of conventional mineral processing or even selective mining failed. In the range of work, research on the lithological composition and Cu content in 300 individual particles (selected from Rudna feed) have been carried out. Using those results, the simulation of gangue separation with an application of sorting have been done. The positive results have been received: introduction of a sorting operation causes, theoretically, removing of approximately 20-30% sorting feed mass as final tailings with Cu losses not bigger than 5-10%. It means that the capacity of Rudna concentrator can be increased proportionally. To confirm those results, industrial sorting trials are necessary, when appropriate sorters will become available. Additionally, one should take also into account that the finest classes of feed (-12.5 mm) could not be concentrated in a sorter. In the range of work, the preliminary tests of the industrial sorter (PRO Secondary Color NIR) for separation of the shale concentrate from Rudna concentrator feed have been carried out. The shale concentrates were received both from 12.5-20 mm class and +20 mm class. The concentrates produced from the coarse classes, for both technological sides had shale content at the level of 48-49%, with recovery of 52.9-60%. In the case of the finer class, shale content in the concentrates for both technological sides amounts to 30.9-35%, at the slightly lower recoveries than for coarse classes. Cu and Corg behavior in the sorting process were checked also, however, the results turned out to be not very interesting. Because the results of shale concentrate production by sorting have a significant potential for improvement, the further researches in this direction have been recommended, however, making them start off from elaboration of a technology for shale concentrate processing and calculation of a total balance of a concentrating process involving flotation and separation.
Effect of some operating variables on the performance of a 150 mm Heavy Medium Cyclone treating high ash Indian Coking Coal
Authors: Charan Thonangi Gouri , Jha G.S. , Sinha K.M.K. , Chattopadhyay U.S. , Sen Kalyan
Published: August 2021

Tests were carried out on a 150 mm heavy medium cyclone test rig treating coal in the size range - 13 +0.5 mm. A total of twenty seven experiments were carried out by varying the parameters like vortex finder diameter, spigot diameter and inlet feed pressure. The effect of these variables on the performance of the 150 mm Heavy Medium Cyclone was investigated. The results indicate that it is possible to achieve about 30.1% clean coal at an ash content of 18.5% at a feed pressure of 10 lb/in2, vortex diameter of 63.75 mm and spigot diameter of 31.5 mm. The tromp curves obtained from operating the cyclone gave a probable error of 0.04, indicating good separation efficiency.
Reuse of Cement Kiln Dust for backfilling and CO2 carbonation
Authors: Lutyński Marcin , Pierzyna Piotr
Published: August 2021

The study aims to investigate possible alternative paths of reusing Cement Kiln Dust in mining technologies or as mineral sorbent for CO2 capture. Properties of CKD and bottom slag slurry were assessed and these were ia.: chemical composition, compressive strength and excess water content. Results show that CKD/bottom slag slurry mixed in the proportion of 25%/75% can be used as a backfill material if concentration of contaminants in the leaching tests is at the acceptable level. Second part of the study was devoted to the assessment of CKD as a sorbent in Calcium looping technologies or for mineral carbonation. TGA and DSC study shows that the rate of CO2 capture (carbonation) is determined by the free CaO content. The highest carbonation rate was within the temperature range of 600-800°C.
Considerations about recovery of critical metals using bio-metallurgy
Authors: Gherghe Săndica Liliana
Published: August 2021

The increased requirement of critical metals due to green technologies needs, together with the geopolitical environment to ensure these metals, has entailed decisive measures to avoid current supply insecurities in each country. These metals are essential to the products and services made and used daily, and contribute to sustaining and growing the economy. Thus, sustainable approaches from technological, environmental, economic and social point of view are needed to recover these metals from different resources. By using resources more efficiently, innovating in the concept of circular economy, it can be assure re-using, re-manufacturing or recycling of valuable materials. In this paper are presented some considerations related to using the waste dumps as potential resources to obtain critical metals by bio-metallurgical processes.
Evaluation of the results of coal jigging process
Authors: Surowiak Agnieszka
Published: August 2021

Quality of applied hard coal fuel to combustion processes influence significantly on process efficiency and effects of its influence on surrounding environment. It is particularly important issue in time of Clean Coal Technologies (CTW). The paper presents the analysis of hard coal beneficiation in a jig for getting an optimal recovery of useful fraction in concentrate (combustible matter) and not useful fraction (ash and sulfur). On the basis of industrial sampling of coal dust jig the density analysis of collected samples of concentrate and tailings was performed in laboratory conditions. In separated fractions of separation products the yields of products were calculated and the contents of ash and total sulfur were marked in them. On the basis of the results of density and chemical analyzes, separation products balance and appropriate calculations the Fuerstenau beneficiation curves were plotted which allowed to evaluate process and compare results of beneficiation of material containing various components. This is a different approach to evaluation of coal beneficiation effects, so far being used mainly for multi-component metals ores. Furthermore, the evaluation of separation preciseness on the basis of separation curves and factors was done and the statistical analysis of mutual correlations of analyzed parameters was done.
Testing the possibility of leaching salt debris obtained from underground excavations
Authors: Pierzyna Piotr , Popczyk Marcin , Suponik Tomasz
Published: August 2021

For many years, the Salt Mine in Bochnia has conducted the extraction and restructuring of underground working to obtain new touristic routes. The works generate a large amount of rock salt material, colloquially called “salt debris”, containing a large part of silty minerals. Due to the large concentration of NaCl which constitutes a threat to the environment, the salt debris may only be stored at hazardous material dumps. This is why the mine works towards the industrial use of the material. Currently, the debris is used to produce a stabilizing backfill mixture that is used for filling the liquidated “Moszczenica” shaft. The liquidation shall be completed in the beginning of 2018 and to continue the management of the salt debris, the mine plans to leach it in a newly constructed system and the saturated brine obtained in the process shall be introduced to underground workings. The paper presents the results of semi-industrial tests of leaching intensity of salt debris, depending on the graining and the time taken by the process. The tests were conducted for three grain classes of the salt debris (0-6, 0-10 and 0-20 mm), at a temperature of 15 °C. The kinetic models of the process has been presented for the obtained results. The obtained results shall be used for the optimization of the operation of the future industrial system and shall be treated as input data for the automation control system.
The influence of ultrasounds on the process of uranium desorption
Authors: Panturu Eugenia , Filcenco-Olteanu Antoneta , Radu Aura Daniela , Zlagnean Marius
Published: August 2021

In the present paper, we have studied the intensification of the desorption process of the complex anions of uranium U(VI), from ion exchange resins under the action of the ultrasonic field. The dynamics of uranium desorption from the anionic resins Purolite A600U/3472 and PM 611 was analyzed, both in standard conditions and with ultrasounds. The use of ultrasounds leads to the substantial growth of desorption kinetics and of the uranium recovery degree. The tests for stability of the resin grains size, mechanical resistance and the capacity of loading with uranium, after the repeated action of the ultrasounds field, emphasized the physical-chemical stability of resins used in the experiment (loading capacity of untreated resin 30.36 mgU/g resin and treated in continuous ultrasonic field 30.85 mgU/g resin).
Development of gear dynamic performance testing machine
Authors: Li Ke , Yu Bo , Shi Zhaoyao , Shu Zanhui , Li Rui
Published: August 2021

With the development of gears towards high temperature, high pressure, high speed and high stress, gear measurement, in which only the static geometric accuracy is considered, is unable to meet the current application requirements. While, the low precision and single function gear tester constrains the measurement of gear dynamic performance. For the resolution of this problem, based on the principle of gear system dynamics and several precision mechanical design techniques, a gear dynamic testing machine has been developed, providing new instruments for gear testing. On the basis of research of the principle of dynamic performance test, the primary measurement items of the testing machine have been determined. The measuring principles of each item and the driving and loading form of the testing machine have been examined. The measurement and control system of the testing machine and its corresponding software have been developed. The instrument can not only obtain the static precision index of the gear, but also obtain the dynamic performance index of the gear in variable working conditions. According to the actual test, the uncertainty of instrument is 3.8 μm and the external disturbance caused by the shaft vibration is less than 0.6 μm, which can meet the 5–6 grade precision gear testing requirement.
Évaluation d’un web-programme d’éducation thérapeutique pour des patients atteints de polypathologie chronique pendant le premier confinement lié à la Covid-19
Authors: Langlumé Lisa , Dauriat Nathalie , Pellecchia Alessandra , Puech Samson Isabelle , Huet Sylvie , de la Tribonnière Xavier
Published: August 2021

Introduction : L’épidémie à Covid-19 a bouleversé la prise en charge des maladies chroniques et a perturbé la majorité des programmes d’éducation thérapeutique (ETP) en France. Des adaptations via le numérique se sont mises en place. Objectifs : Étude exploratoire évaluant la faisabilité et la pertinence d’un web-programme d’ETP pendant le premier confinement lié à la Covid-19 ; réflexions sur l’intérêt des web-ateliers par rapport au présentiel. Méthode : Adaptation d’un programme sur la polypathologie chronique porté par une unité transversale d’éducation du patient (UTEP), pour un web-programme hebdomadaire avec 5 web-ateliers, auto-formation et organisation de l’équipe à la pratique des web-ateliers, réflexions collectives sur l’intérêt et les limites des web-ateliers. Résultats : Du 1er avril à fin mai 2020, 51 patients ont été inclus, et 32 ont terminé un cycle éducatif (minimum 3 web-ateliers). Sur en moyenne 6,1 objectifs pédagogiques convenus au départ, 92,2 % ont été totalement ou partiellement acquis. La satisfaction moyenne à l’issue de chacun des web-ateliers se situait entre 8,42 et 9,53 sur 10. Les patients ont ressenti un soutien psychologique et une possibilité de sortir de l’isolement social. Parmi les avantages et limites des web-ateliers : meilleure accessibilité (géographique, disponibilité), maintien de la dynamique de groupe à distance, limites techniques à prendre en compte. Discussion et conclusion : Le web-programme polypathologie avec 5 web-ateliers a été jugé faisable, acceptable et pertinent par les patients et intervenants. Les ateliers en distanciel paraissent répondre aux besoins des patients en période de pandémie et au-delà.
Hufrehe – Korrektur der Grundkonstitution durch Homöopathie
Authors: Milleder Beatrice
Published: August 2021

Ursachen und Symptome der Hufrehe variieren individuell in weiten Grenzen. Für dauerhafte Abhilfe kann daher nur eine Korrektur der Grundkonstitution des jeweiligen Tieres sorgen. Hierbei ist die klassische Homöopathie von großem Nutzen. Anhand zweier Fallbeispiele wird aufgezeigt, wie durch das richtige konstitutionelle Mittel das erneute Auftreten von Rehe verhindert und die Lebensqualität betroffener Tiere verbessert werden kann.
Einsamkeit und Lebenszufriedenheit auf hoher See
Authors: Oldenburg Marcus , Reck Chiara
Published: August 2021

Durch die lange Trennung von Familie und Freunden fühlen sich viele Seeleute während ihres monatelangen Einsatzes einsam. Wichtig sind daher zwischenmenschliche Kontakte an Bord und Kommunikationsmöglichkeiten nach Hause 1. Beides stellt sich auf See u. U. erschwert dar: Erstens ist die Besatzung zumeist multinational zusammengestellt, was nicht selten zu Verständigungsproblemen führt. Zweitens besteht keine permanente Internetverbindung und jede Einwahl verursacht z. T. erhebliche Kosten, sodass Seeleute den Kontakt oft auf das Nötigste begrenzen.
Validation of the Repetitions in Reserve Rating Scale in Paralympic Powerlifting Athletes
Authors: Neto Frederico Ribeiro , Dorneles Jefferson Rodrigues , Aidar Felipe José , Gonçalves Carlos Wellington , Veloso João , Costa Rodrigo Rodrigues Gomes
Published: August 2021

The present study aimed to validate the perceived exertion scale based on the repetitions in reserve (RIR) of Paralympic Powerlifting (PP) athletes. Twenty-one PP athletes were assessed in the one-maximum repetition test (1RM) of the bench press exercise, maximum repetition strength tests with loads corresponding to 90, 85, 80, and 75% of 1RM, and 4-repetitions strength tests (4-repST) with 100, 90, 85, 80, and 75% of the 1RM. The RIR scale was assessed after each set of the 4-repST and compared to the 1RM and maximum strength tests. For criterion validity, the total estimated repetition was significantly lower compared to the maximum strength test repetitions in the lower scores of the RIR scale (median=7.0 vs. 9.0 for 75% of 1RM). The total estimated repetition correlation with maximum strength was very high and significant (ICC=0.91). Using the Bland and Altman method, the difference between means was 0.9 reps, and the interval around differences was 6.4 reps. For construct validity, and the RIR scale presented high correlation with 1RM intensities (rho=0.86, p≤0.05). The RIR scale was validated and coaches and sports trainers can use this monitoring tool to ensure submaximal loads when improving lift technique, which is extremely rigorous in PP.
Alterações hematológicas após implante de matriz óssea desmineralizada caprina em modelo de defeito ulnar crítico em coelhos
Authors: Alimi Olawale Alimi , Abubakar Adamu Abdul , Yakubu Abubakar Sadiq , Shehu Sani Abdullahi , Abdulkadir Salman Zubairu , Oviawe Ekaete Ime
Published: August 2021

Objetivo Diversos modelos animais têm sido usados em estudos sobre enxertos ósseos e o tratamento de fraturas, mas as respostas hematológicas são raramente relatadas. Este estudo descreveu as alterações hematológicas observadas em coelhos submetidos a xenoenxertos de matriz óssea desmineralizada caprina (MODC).

Métodos Vinte e quatro (24) coelhos machos (2,5 ± 0,5 kg) foram adquiridos para este estudo e divididos aleatoriamente em três grupos: enxerto ósseo autólogo (EOA); controle negativo sem preenchimento (SP) e matriz óssea desmineralizada caprina (MODC). Amostras de sangue foram coletadas por punção cardíaca sob anestesia com xilazina-quetamina no dia 0 (para estabelecimento dos valores basais) e aos dias 28 e 56 após a cirurgia; essas amostras foram submetidas à análise manual em até 2 horas após a coleta. A análise estatística foi composta por análise de variância (ANOVA) de dois fatores com medidas repetidas, e o valor de p < 0,05 foi considerado significativo.

Resultados Houve uma diferença geral significativa nos números de leucócitos totais (p = 0,0043), neutrófilos (p < 0,0001), monócitos (p = 0,0184) e hemácias (p = 0,003), na concentração de hemoglobina (p < 0,0001) e no hematócrito (p < 0,0001) ao longo dos dias e entre os grupos de tratamento. No entanto, não houve diferença global significativa no número de linfócitos (p = 0,4923), basófilos (p = 0,4183) e eosinófilos (p = 0,4806) entre os dias.

Conclusão A resposta ao enxerto de MODC em coelhos é, portanto, caracterizada por leucocitose intensa com neutrofilia, linfocitose e monocitose no 28° dia após o procedimento. Esses dados podem basear a utilização da hematologia no monitoramento da resposta corporal em modelos animais de enxerto ósseo.
Tratamento de fraturas acetabulares de duas colunas por dupla via extrapélvica: Três casos clínicos
Authors: Boavida João , Ribeiro Paulo Gil , Costa Paulo , Quintas Catarina , Moura Diogo Lino , Figueiredo António
Published: August 2021

As fraturas de duas colunas do acetábulo segundo a classificação de Letournel são das mais comuns em frequência, indicação e complexidade cirúrgica. Estas resultam essencialmente de mecanismos de compressão lateral e caracterizam-se por originarem um acetábulo desconectado do esqueleto axial. O seu tratamento cirúrgico pode incluir: abordagem anterior ou posterior isolada; combinadas, no mesmo tempo cirúrgico ou não; ou abordagens alargadas. Os autores apresentam outra opção cirúrgica com associação de via de Kocher-Langenbeck e abordagem da crista ilíaca simultânea e no mesmo posicionamento (decúbito lateral) com base nos três primeiros casos clínicos realizados e seus resultados clínicos e imagiológicos. Para além da apresentação dos casos, é feita uma descrição dos três fragmentos característicos deste tipo de fraturas acetabulares, da via de abordagem e da sequência de redução realizada. Pelos resultados obtidos e vantagens associadas, os autores acreditam que a adição da abordagem da crista ilíaca à via de Kocher-Langenbeck pode ser uma opção muito atrativa a ter em conta no tratamento cirúrgico de fraturas de duas colunas do acetábulo devidamente selecionadas.
Workplace Violence in Emergency Departments in Turkey
Authors: Sabak Mustafa , Al-Hadidi Ameer , Oktay Mehmet Murat , Al Behcet , Kazaz Tanyeli , Kowalenko Terry , Hakmeh Wael
Published: August 2021

Background Studies on workplace violence against physicians in emergency departments (EDs) in Turkey are lacking.

Methods To describe the frequency and types of workplace violence, a 34-question online survey of the past 12 months was sent to physicians working in EDs in Turkey. Types of violence were categorized as verbal threats, physical assaults, confrontation, stalking, and sexual harassment.

Results A total of 366 physicians completed the survey; 4 were excluded (minimum 20 hours/week). Sixty-two percent of respondents were men. Ninety-nine percent reported verbal abuse and 54% reported physical violence. Family members, not patients, were the most common perpetrators of every form of workplace violence. Hospitals limiting the number of visitors and loitering had 14% reduction in physical threats. Only 23% of respondents indicated that their hospital offered information about preventing and managing workplace violence even though 86% noted interest. Only 1% never had fear, even though 89% indicated they had security staff. Over 89% felt that hospital security was lacking in number and ability to protect. For 82%, workplace violence affected their ability to provide patient care. Ninety percent indicated that current laws do not adequately protect them. There was also no statistically significant difference in any type of workplace violence based on the timing or length of shifts, type of hospital, or number of hours worked. Of all types of violence reported, only stalking demonstrated a statistically significant difference between men and women.

Conclusion Workplace violence is a real danger for physicians working in EDs in Turkey, similar to other countries, demonstrating that this problem transcends borders. Further studies should assess root causes of violent behaviors of patients and their visitors, as well as possible (administrative, social, and legal) mechanisms to minimize such violence. Hospitals that limited the number of visitors and empowered security officers were associated with decreased violence.
Turning Problems into Opportunities: How to Resume Urological Elective Surgery Using a Scoring System during COVID-19 Outbreak
Authors: Chavarriaga Julian , Lopez-Ramos Hugo , Prada Juan , Fernandez Nicolas
Published: August 2021

Objective Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), which is the largest pandemic in the last century and has created a health care crisis worldwide. Contingency plans have led to put on hold all urological elective surgeries. The aim of the present article is to report the adaptation of the Medically Necessary Time-Sensitive (MeNTS) scoring system to triage patients who were awaiting urological elective surgery during the COVID-19 pandemic.

Methods The present study was conducted as a part of a necessary transition of care delivery at a tertiary care institution in order to re-establish urological elective surgery. We triaged all urological elective surgeries with the MeNTS instrument and proposed a cutoff value of 45 points to avoid complications in the COVID-19 crisis while resuming elective procedures.

Results A total of 91 patients awaiting elective urological surgery pending to be rescheduled were identified. Their median age was 60.5 years old (interquartile range [IQR]: 46–93). Twenty-five patients were American Society of Anesthesiologists (ASA) class I, 51 (56%) were class II, and 12 (13%) were class III. The median MeNTS score was 42 points (IQR: 36–59). Twenty-nine patients had a MeNTS score > 45 and were advised to postpone their surgery. Sixty-two had a score ≤ 45 and were gradually rescheduled.

Conclusions The present study may have practical implications regarding the selection of urological elective surgeries in the challenging health care situation caused by the COVID-19 pandemic. Our real-life data showed us that 32% of our procedures must be postponed, and 68% could be carefully considered and gradually rescheduled for surgery.
Platelet Surface Protein Expression and Reactivity upon TRAP Stimulation after BNT162b2 Vaccination
Authors: Klug Melissa , Lazareva Olga , Kirmes Kilian , Rosenbaum Marc , Lukas Marina , Weidlich Simon , Spinner Christoph D. , von Scheidt Moritz , Gosetti Rosanna , Baumbach Jan , Ruland Jürgen , Condorelli Gianluigi , Laugwitz Karl-Ludwig , List Markus , Bernlochner Isabell , Bongiovanni Dario
Published: August 2021

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection induces a coagulopathy characterized by platelet activation and a hypercoagulable state with an increased incidence of cardiovascular events. The viral spike protein S has been reported to enhance thrombosis formation, stimulate platelets to release procoagulant factors, and promote the formation of platelet–leukocyte aggregates even in absence of the virus. Although SARS-CoV-2 vaccines induce spike protein overexpression to trigger SARS-CoV-2-specific immune protection, thrombocyte activity has not been investigated in this context. Here, we provide the first phenotypic platelet characterization of healthy human subjects undergoing BNT162b2 vaccination. Using mass cytometry, we analyzed the expression of constitutive transmembrane receptors, adhesion proteins, and platelet activation markers in 12 healthy donors before and at five different time points within 4 weeks after the first BNT162b2 administration. We measured platelet reactivity by stimulating thrombocyte activation with thrombin receptor-activating peptide. Activation marker expression (P-selectin, LAMP-3, LAMP-1, CD40L, and PAC-1) did not change after vaccination. All investigated constitutive transmembrane proteins showed similar expressions over time. Platelet reactivity was not altered after BNT162b2 administration. Activation marker expression was significantly lower compared with an independent cohort of mild symptomatic COVID-19 patients analyzed with the same platform. This study reveals that BNT162b2 administration does not alter platelet protein expression and reactivity.
Reflections on integrated research from community engagement in peatland restoration
Authors: Fleming A. , Agrawal S. , Dinomika  , Fransisca Y. , Graham L. , Lestari S. , Mendham D. , O’Connell D. , Paul B. , Po M. , Rawluk A. , Sakuntaladewi N. , Winarno B. , Yuwati T. W.
Published: August 2021

Community engagement and integrated research are key approaches to solving complex socio-ecological challenges. This paper describes the experience of bringing together a team of natural and social scientists from Australia and Indonesia in the ‘Gambut Kita’ (translated as ‘Our Peat’) project. Gambut Kita aims to produce new knowledge and support efforts to successfully, and equitably, restore Indonesia’s tropical peatlands and ensure that livelihoods can be maintained on restored (rewetted) landscapes. The paper focuses on experiences of using community engagement for integrated research. It discusses three community engagement approaches used in the project—resilience, adaptation pathways and transformation approach (RAPTA), participatory rural appraisal (PRA), and community-led analysis and planning (CLAP). It also describes the qualitative analysis of 14 interviews with the project team of lessons learned in community engagement for integrated research. ‘Criteria for success’ from the literature on international development projects is used to assess progress. The findings highlight the specific complexities of working across countries and cultures. Successful community engagement is not so much about the ‘tool’ but about the trust, agency, and support to change. The tools do, however, have different strengths. PRA and CLAP can build deep community understanding and relationships. RAPTA has strengths in framing visions and pathways to the future, systems thinking, anticipatory learning, and taking a cross-scale systems view which is required to solve many of the problems manifesting at local or community scales. Similarly, success in integrated research is not just about individuals, but structures (e.g. explicit process) and infrastructure (e.g. access to technology). These findings suggest that integrated research needs special considerations in terms of design, and these relate across scales to individual researchers as well as teams, leaders and organisations. Integrated research projects need careful, inclusive, iterative management with a lot of interaction to learn from each other, build a common vision, achieve clarity of roles, and share emerging findings.
Phase-locking intermittency induced by dynamical heterogeneity in networks of thermosensitive neurons
Authors: Rossi K. L. , Budzinski R. C. , Boaretto B. R. R. , Prado T. L. , Feudel U. , Lopes S. R.
Published: August 2021

In this work, we study the phase synchronization of a neural network and explore how the heterogeneity in the neurons’ dynamics can lead their phases to intermittently phase-lock and unlock. The neurons are connected through chemical excitatory connections in a sparse random topology, feel no noise or external inputs, and have identical parameters except for different in-degrees. They follow a modification of the Hodgkin–Huxley model, which adds details like temperature dependence, and can burst either periodically or chaotically when uncoupled. Coupling makes them chaotic in all cases but each individual mode leads to different transitions to phase synchronization in the networks due to increasing synaptic strength. In almost all cases, neurons’ inter-burst intervals differ among themselves, which indicates their dynamical heterogeneity and leads to their intermittent phase-locking. We argue then that this behavior occurs here because of their chaotic dynamics and their differing initial conditions. We also investigate how this intermittency affects the formation of clusters of neurons in the network and show that the clusters’ compositions change at a rate following the degree of intermittency. Finally, we discuss how these results relate to studies in the neuroscience literature, especially regarding metastability.
A comprehensive calibration method for non-orthogonal error and scale factor error of triaxial Helmholtz coil
Authors: Yue Liangguang , Cheng Defu , Wang Yi , Wang Mingchao , Zhao Jing
Published: August 2021

In order to calibrate the non-orthogonal error and scale factor error of triaxial Helmholtz coil, a comprehensive error calibration method is proposed in this paper. The comprehensive error model is established first, and then the method to generate a frequency-controllable spatial rotating magnetic field whose magnetic field intensity is constant based on triaxial Helmholtz coil is introduced. Based on the fact that the magnetic field intensity generated by the current through the coil is constant, the objective function is constructed and the error parameters are solved using the least-squares fitting method. Simulation experiments and field tests prove the effectiveness and feasibility of this method. The most obvious finding to emerge from this study is that the proposed method is not only suitable for the electromagnetic shielding room environment but also suitable for the field tests in the presence of a background geomagnetic field far away from urban electricity interference. The root mean square error value is reduced to 0.7 nT from 298.2 nT in the electromagnetic shielding room, and it is reduced to 0.8 nT from 299.0 nT in the wild. Compared to the two-step calibration method, the proposed method reduces the sampling time by controlling the frequency of the rotating magnetic field and reduces the influence of the changes of the background geomagnetic field on the experimental results. This method has better anti-interference ability. Because the modulus of the background geomagnetic field has no effect on this method, it gets rid of the dependence on large current or background geomagnetic field shielding devices. Comparative experiments and repetitive experiments verify the practicability and stability of this method.
Ground states for a linearly coupled indefinite Schrödinger system with steep potential well
Authors: Lin Ying-Chieh , Wang Kuan-Hsiang , Wu Tsung-fang
Published: August 2021

In this paper, we study a class of linearly coupled Schrödinger systems with steep potential wells, which arises from Bose–Einstein condensates. The existence of positive ground states is investigated by exploiting the relation between the Nehari manifold and fiberring maps. Some interesting phenomena are that we do not need the weight functions in the nonlinear terms to be integrable or bounded and we can relax the upper control condition of the coupling function. Moreover, the decay rate and concentration phenomenon of positive ground states are also studied.
Self-interaction-corrected Kohn–Sham effective potentials using the density-consistent effective potential method
Authors: Diaz Carlos M. , Basurto Luis , Adhikari Santosh , Yamamoto Yoh , Ruzsinszky Adrienn , Baruah Tunna , Zope Rajendra R.
Published: August 2021

Density functional theory (DFT) and beyond-DFT methods are often used in combination with photoelectron spectroscopy to obtain physical insights into the electronic structure of molecules and solids. The Kohn–Sham eigenvalues are not electron removal energies except for the highest occupied orbital. The eigenvalues of the highest occupied molecular orbitals often underestimate the electron removal or ionization energies due to the self-interaction (SI) errors in approximate density functionals. In this work, we adapt and implement the density-consistent effective potential method of Kohut, Ryabinkin, and Staroverov [J. Chem. Phys. 140, 18A535 (2014)] to obtain SI-corrected local effective potentials from the SI-corrected Fermi–Löwdin orbitals and density in the Fermi–Löwdin orbital self-interaction correction scheme. The implementation is used to obtain the density of states (photoelectron spectra) and HOMO–LUMO gaps for a set of molecules and polyacenes. Good agreement with experimental values is obtained compared to a range of SI uncorrected density functional approximations.
Electronic structure of 2D quaternary materials and of their van der Waals heterostructures
Authors: Lazaar Koussai , Gueddida Saber , Abboud Ali , Said Moncef , Rocca Dario , Lebègue Sébastien
Published: August 2021

The properties of the two dimensional quaternary compounds AgScP2Se6, AgBiP2Se6, CuBiP2Se6, and CuInP2S6 and the corresponding van der Waals heterostructures are studied using density functional theory. These compounds are dynamically stable, their electronic bandgaps range from 2.13 to 2.68 eV, and the positions of their band edges are suitable for their use for water splitting. Among the different heterostructures made from these monolayers, it is demonstrated that AgBiP2Se6/AgScP2Se6 and AgBiP2Se6/CuBiP2Se6 are type II heterostructures, which allow an efficient electron–hole separation. Then, we studied the electronic properties of the graphene/quaternary-2D-compound heterostructures: a shift of the graphene Dirac-point above the Fermi level is observed, which corresponds to a p-type heterostructure. Overall, this family of materials appears to be very promising for optical and electronic applications.
Controlling thermal conductance using three-dimensional phononic crystals
Authors: Heiskanen Samuli , Puurtinen Tuomas A. , Maasilta Ilari J.
Published: August 2021

Controlling thermal transport at the nanoscale is vital for many applications. Previously, it has been shown that this control can be achieved with periodically nanostructured two-dimensional phononic crystals for the case of suspended devices. Here, we show that thermal conductance can also be controlled with three-dimensional phononic crystals, allowing the engineering of the thermal contact of more varied devices without the need for suspension in the future. We show the experimental results obtained at sub-Kelvin temperatures for two different period three-dimensional crystals and for a bulk control structure. The results show that the conductance can be enhanced with the phononic crystal structures in our geometry. This result cannot be fully explained by the simplest theory taking into account the coherent modification of the phonon band structure, calculated by finite element method simulations.
Molecular dynamic study of alcohol-based deep eutectic solvents
Authors: Ferreira Elisabete S. C. , Voroshylova Iuliia V. , Figueiredo Nádia M. , Cordeiro M. Natália D. S.
Published: August 2021

The applicability of deep eutectic solvents is determined by their physicochemical properties. In turn, the properties of eutectic mixtures are the result of the components’ molar ratio and chemical composition. Owing to the relatively low viscosities displayed by alcohol-based deep eutectic solvents (DESs), their application in industry is more appealing. Modeling the composition–property relationships established in polyalcohol-based mixtures is crucial for both understanding and predicting their behavior. In this work, a physicochemical property–structure comparison study is made between four choline chloride polyalcohol-based DESs, namely, ethaline, propeline, propaneline, and glyceline. Physicochemical properties obtained from molecular dynamic simulations are compared to experimental data, whenever possible. The simulations cover the temperature range from 298.15 to 348.15 K. The simulated and literature experimental data are generally in good agreement for all the studied DESs. Structural properties, such as radial and spatial distribution functions, coordination numbers, hydrogen bond donor (HBD)–HBD aggregate formation, and hydrogen bonding are analyzed in detail. The higher prevalence of HBD:HBD and HBD:anion hydrogen bonds is likely to be the major reason for the relatively high density and viscosity of glyceline as well as for lower DES self-diffusions.
Principles and properties of phononic crystal waveguides
Authors: Laude V.
Published: August 2021

Strongly confined waveguiding is one of the main applications of phononic crystals that can be achieved at any frequency and scale. Phononic crystal waveguides replace the cladding of classical homogeneous waveguides by a crystal possessing a complete phononic bandgap. We review the different material systems used to implement phononic crystal waveguides and how waveguiding is obtained by confining waves in a core or by coupling defects along a given direction. Finally, we introduce topological principles to design defect-less waveguides by exploiting the symmetry of crystals.
Transition of wake flows past two circular or square cylinders in tandem
Authors: Rastan M. R. , Alam Md. Mahbub
Published: August 2021

This paper presents the dependence of flow transitions and flow regimes on Reynolds number Re (≤ 105) and scaled cylinder center-to-center spacing S* (≤ 10) for two tandem cylinders. Both circular and square cross-sectional geometries are considered, and a comparison of results is made between the two geometries. To do so, data available from the literature are collected, and supplementary numerical simulations are done to complement the literature data so as to provide clear-cut flow maps in the Re–S* domain. We identified the borders of Re- and S*-dependent flows, including steady, unsteady, transition, slender/extended body, alternating reattachment, bistable, and co-shedding flows. The flow interference between two tandem cylinders with S* < S*cr is susceptible to stabilize the flow that requires a higher Re for the onset of vortex shedding than the isolated cylinder counterpart, where S*cr is the critical spacing for the onset of co-shedding flow. Besides, the flow interference generally postpones and advances the onset of secondary vortex shedding associated with the transition from two- to three-dimensional vortex shedding for S* < S*cr and S* > S*cr, respectively. Two flow maps are made for the two geometries, both yielding fundamental contributions toward a better understanding of the flow interference effect on various flow transitions. The flow maps determine the regions of a dearth of knowledge, which future studies may pay attention to. Finally, the drag inversion, hysteresis, and flow patterns in the proximity of the onset of vortex shedding for tandem square cylinders (1.5 ≤ S* ≤ 7) are discussed.
The influence of the Southern Oscillation Index on the timing of breeding of a forest-bird community in south-eastern Australia
Authors: Marchant R. , Guppy M. , Guppy S.
Published: August 2021

Context Long-term changes in the breeding phenology of bird communities have been widely studied. For many species, breeding appears to be starting earlier as temperatures increase. For south-eastern Australia, such a trend has not so far been demonstrated. Aims The aim was to determine how the date of laying of the first egg (FE; for sedentary species) or arrival times (for migratory species) responded to climatic factors such as rainfall, air temperature and the Southern Oscillation Index (SOI), and whether FE or arrival time showed a trend through time. Methods The date of laying of the first egg (FE) for 13 sedentary species of birds was recorded over 18 (1975–1984 and 2007–2014) breeding seasons (August to January) at a single site in a coastal forest in south-eastern Australia. The arrival times for seven migratory species were also recorded for these seasons. Key results Linear mixed models showed that FE was negatively correlated with the mean monthly SOI for April to July (A-J SOI), the period directly before the breeding season. Eggs were laid earlier when A-J SOI was positive and later when it was negative. SOIs calculated over different combinations of months showed that those for the January to March period had no influence on FE. FE was not related to minimum or maximum temperatures during April to July, despite increases in temperature between 1975 and 2014, nor was it related to rainfall between April and July. Mixed linear models showed that arrival date for migratory species became earlier between 1975 and 2014, but was uninfluenced by A-J SOI or rainfall. Conclusions Migratory species arrived earlier by 0.27 days per year. However, this was at least an order of magnitude smaller than annual temporal changes in FE for sedentary species (6–7 days) associated with cyclical SOI fluctuations. Changes in SOI dominated the annual breeding phenology of the community. Implications The mechanisms by which A-J SOI influences the timing of nesting may be related to the primary productivity of forests and the influence of this on insect abundance. There are few data on these factors.
Phenotypic plasticity in plant defense across life stages: Inducibility, transgenerational induction, and transgenerational priming in wild radish
Authors: Sobral Mar , Sampedro Luis , Neylan Isabelle , Siemens David , Dirzo Rodolfo
Published: August 2021

As they develop, many plants deploy shifts in antiherbivore defense allocation due to changing costs and benefits of their defensive traits. Plant defenses are known to be primed or directly induced by herbivore damage within generations and across generations by long-lasting epigenetic mechanisms. However, little is known about the differences between life stages of epigenetically inducible defensive traits across generations. To help fill this knowledge gap, we conducted a multigenerational experiment to determine whether defense induction in wild radish plants was reflected in chromatin modifications (DNA methylation); we then examined differences between seedlings and reproductive plants in current and transgenerational plasticity in chemical (glucosinolates) and physical (trichomes) defenses in this species. Herbivory triggered genome methylation both in targeted plants and their offspring. Within one generation, both defenses were highly inducible at the seedling stage, but only chemical defenses were inducible in reproductive plants. Across generations, herbivory experienced by mother plants caused strong direct induction of physical defenses in their progeny, with effects lasting from seedling to reproductive stages. For chemical defenses, however, this transgenerational induction was evident only in adults. Transgenerational priming was observed in physical and chemical defenses, particularly in adult plants. Our results show that transgenerational plasticity in plant defenses in response to herbivore offense differs for physical and chemical defense and changes across plant life stages.
Trade-offs among transport, support, and storage in xylem from shrubs in a semiarid chaparral environment tested with structural equation modeling
Authors: Pratt R. B. , Jacobsen A. L. , Percolla M. I. , De Guzman M. E. , Traugh C. A. , Tobin M. F.
Published: August 2021

Significance

Plant vascular systems play a central role in global water and carbon cycles and drought resistance. These vascular systems perform multiple functions that affect the fitness of plants, and trade-offs are present among these functions. Some trade-offs are well established, but studies have not examined the full suite of functions of these complex systems. Here, we used a powerful multivariate method, structural equation modeling, to test hypotheses about the trade-offs that govern this vital and globally important tissue. We show that xylem traits are broadly governed by trade-offs related to transport, mechanical support, and storage, which are rooted in cellular structure, and that the level of dehydration experienced by plants in the field exerts a strong influence over these relationships.
An image-computable model of how endogenous and exogenous attention differentially alter visual perception
Authors: Jigo Michael , Heeger David J. , Carrasco Marisa
Published: August 2021

Significance

Visual attention alters perception. Endogenous (voluntary) and exogenous (involuntary) spatial attention shape perception by prioritizing some visual information and ignoring others. Each attention type induces different perceptual consequences. Endogenous attention flexibly optimizes the visibility of fine-grain or coarse-scale visual features, whereas exogenous attention inflexibly enhances fine details, even when detrimental to perception. The computations that govern these differences are unknown. We developed a computational model that predicts human behavior and these distinct attentional effects directly from visual displays used in previous experiments. At the model’s core, each attention type adjusts sensory processing with different selectivity across visual detail. The model explains several phenomena, including uniform improvements induced by endogenous attention and visual improvements and impairments induced by exogenous attention.