bluuebunny/crossref_metadata_2025 huggingface dataset:
Semisimplification for subgroups of reductive algebraic groups
Authors: Bate Michael , Martin Benjamin , Röhrle Gerhard
Published: November 2020

LetGbe a reductive algebraic group—possibly non-connected—over a fieldk, and letHbe a subgroup ofG. If$G= {GL }_n$, then there is a degeneration process for obtaining fromHa completely reducible subgroup$H'$ofG; one takes a limit ofHalong a cocharacter ofGin an appropriate sense. We generalise this idea to arbitrary reductiveGusing the notion ofG-complete reducibility and results from geometric invariant theory over non-algebraically closed fields due to the authors and Herpel. Our construction produces aG-completely reducible subgroup$H'$ofG, unique up to$G(k)$-conjugacy, which we call ak-semisimplificationofH. This gives a single unifying construction that extends various special cases in the literature (in particular, it agrees with the usual notion for$G= GL _n$and with Serre’s ‘G-analogue’ of semisimplification for subgroups of$G(k)$from [19]). We also show that under some extra hypotheses, one can pick$H'$in a more canonical way using the Tits Centre Conjecture for spherical buildings and/or the theory of optimal destabilising cocharacters introduced by Hesselink, Kempf, and Rousseau.
FIXED POINT THEOREM FOR AN INFINITE TOEPLITZ MATRIX
Authors: ABRAMOV VYACHESLAV M.
Published: November 2020

For an infinite Toeplitz matrix T with nonnegative real entries we find the conditions under which the equation
$\boldsymbol {x}=T\boldsymbol {x}$
, where
$\boldsymbol {x}$
is an infinite vector column, has a nontrivial bounded positive solution. The problem studied in this paper is associated with the asymptotic behaviour of convolution-type recurrence relations and can be applied to problems arising in the theory of stochastic processes and other areas.
Old age as a new class or an outdated social category? Objective and symbolic representations of later life
Authors: Gilleard Chris
Published: November 2020

Age has become an increasingly contested form of division within contemporary society, with some writers suggesting age has become ‘the new class’ while others point to increasing ‘ageism’ in society. In exploring such competing claims, this paper examines the basis for considering age as a social class, category or group. Drawing upon Bourdieu's writings on classification and the criteria for what constitutes a social class or category and the ‘objective’ and ‘symbolic’ criteria defining it, the paper argues that the material criteria for distinguishing between ‘retired’ and ‘working-age’ households have almost disappeared. At the same time, the symbolic representation of age is no longer confined to the parameters of poverty. Shorn of its objective distinction, the symbolic representation of old age seems to have bifurcated, between a generational identity where older people are represented as an advantaged group and an aged identity still essentialised as old and weak. The dissolution of an objective material basis for framing age has taken away much of the underlying basis for a coherent symbolic categorisation of age. Later life might better be seen as a contested symbolic space, framed by the dual axes of socio-historical generation and corporeal, chronological agedness.
Global Englishes and language teaching: A review of pedagogical research
Authors: Rose Heath , McKinley Jim , Galloway Nicola
Published: November 2020

The rise of English as a global language has led scholars to call for a paradigm shift in the field of English language teaching (ELT) to match the new sociolinguistic landscape of the twenty-first century. In recent years a considerable amount of classroom-based research and language teacher education (LTE) research has emerged to investigate these proposals in practice. This paper outlines key proposals for change in language teaching from the related fields of World Englishes (WE), English as a lingua franca (ELF), English as an international language (EIL), and Global Englishes, and critically reviews the growing body of pedagogical research conducted within these domains. Adopting the methodology of a systematic review, 58 empirical articles published between 2010 and 2020 were shortlisted, of which 38 were given an in-depth critical review and contextualized within a wider body of literature. Synthesis of classroom research suggests a current lack of longitudinal designs, an underuse of direct measures to explore the effects of classroom interventions, and under-representation of contexts outside of university language classrooms. Synthesis of teacher education research suggests future studies need to adopt more robust methodological designs which measure the effects of Global Englishes content on teacher beliefs and pedagogical practices both before and throughout the programme, and after teachers return to the classroom.
Prescribing French: A corpus-linguistic approach to official terminology in French newspapers
Authors: Zsombok Gyula
Published: November 2020

In France, English is often perceived as a negative influence on the language in the eyes of purist institutions like the French Academy. Terminological commissions have been established to replace foreign expressions with French terminology that is regularly published in the Journal officiel de la République française. Although the Toubon Law of 1994 prescribes the use of this terminology in government publications, speakers are merely encouraged to do so. This article investigates the variation between English lexical borrowings and their prescribed equivalents in a large newspaper corpus containing articles from 2000 to 2017 in order to see whether formal written language complies with the purist recommendations. Time is treated with a new dynamic approach: the probability of using a prescribed term is estimated three years before and three years after official prescription. Fifty-four target terms are selected from the lexical fields of computer science, entertainment industry and telecommunication, including emblematic prescribed words such as courriel and mot-dièse. The analysis reveals that prescription is only effective when it follows already attested use. Furthermore, conservative newspapers show higher proportions of recommended terminology, especially as compared to newspapers specializing in technology.
Dosimetric characteristics of VMAT plans with respect to a different increment of gantry angle size for Ca cervix
Authors: Natraj Munirathinam , Pawaskar P. N. , Chairmadurai Arun
Published: November 2020

Aim:

We have investigated the influence in volumetric-modulated arc therapy (VMAT) plans by a sequence of increment of gantry angle (IGA) in definitive radiotherapy treatment for cervical cancer. The plans are quantitatively analysed in terms of conformity index (CI), heterogeneity index (HI), dose–gradient index (DGI), target coverage (TC) by prescription dose, monitor unit (MU) usage, control points (CPs) and dose to organs.

Materials and Methods:

In this retrospective study, we selected 27 patients with cervical cancer having aged between 54 and 69. All the patients enrolled in this study were at T3N1M0 stage of cervical cancer. The prescription dose to planning target volume (PTV) was 50 Gy and was administered in 2 Gy/fraction through VMAT technique. VMAT plans were optimised by varying the parameter ‘IGA’ as 10, 20, 30 and 40°.

Results:

Homogenous dose distribution within PTV and TC by prescription dose was significantly enhanced (p < 0·05) with larger IGA. The difference between volume receiving 15 Gy (V15Gy) in bowel was up to 10% with larger IGA (30 and 40°) and V25Gy in femoral head was up to 3% with smaller IGA (10 and 20°). CPs were enhanced and MU usage was reduced with larger IGA (30 and 40°). IGA 40° had reduced the MU usage than IGA 30° but the CI and DGI were compromised due to large MLC field segments.

Conclusion:

This study recommends that the larger IGA could yield better results when the number of sectors is even, for a cervical cancer patient. However, more data from more patients need to be obtained and analysed to make this an evidence-based hypothesis.
MEANINGS AND IMPACTS OF CONFEDERATE MONUMENTS IN THE U.S. SOUTH
Authors: Britt Lucy , Wager Emily , Steelman Tyler
Published: November 2020

How do citizens interpret contentious symbols that pervade their community? And what downstream effects does state protection of these symbols have on how citizens of different backgrounds feel they belong in their community? We approach these questions through the lens of race and Confederate monuments in the American South. We rely on two original surveys to illustrate 1) the symbolic meanings Americans attach to these monuments and 2) how state protection of them impacts residents’ feelings of belonging. We find that perceptions of Confederate monuments vary by race: White U.S. residents are drastically less likely to perceive them as symbolic of racial injustice than are Black U.S. residents. Further, state protection of Confederate monuments leads to a diminished sense of belonging among Blacks, while leaving Whites unaffected. This research moves beyond scholarship examining simple support for or opposition toward contentious symbols, developing a deeper understanding of what meaning those symbols can hold for individuals and what their impacts are on individuals’ feelings of belonging and engagement in their communities.
Effects of low-dose applications of 2,4-D and dicamba on cucumber and cantaloupe
Authors: Hand Lavesta C. , Vance Jenna C. , Randell Taylor M. , Shugart John , Gray Thomas , Luo Xuelin , Culpepper A. Stanley
Published: November 2020

Agronomic crops engineered with resistance to 2,4-D or dicamba have been commercialized and widely adopted throughout the United States. Because of this, increased use of these herbicides in time and space has increased damage to sensitive crops. From 2014 to 2016, cucumber and cantaloupe studies were conducted in Tifton, GA, to demonstrate how auxinic herbicides (namely, 2,4-D or dicamba), herbicide rate (1/75 or 1/250 field use), and application timing (26, 16, and 7 d before harvest [DBH] of cucumber; 54, 31, and 18 DBH of cantaloupe) influenced crop injury, growth, yield, and herbicide residue accumulation in marketable fruit. Greater visual injury, reductions in vine growth, and yield loss were observed at higher rates when herbicides were applied during early-season vegetative growth compared with late-season with fruit development. Dicamba was more injurious in cucumber, whereas cantaloupe responded similarly to both herbicides. For cucumber, total fruit number and relative weights were reduced (16% to 19%) when either herbicide was applied at the 1/75 rate 26 DBH. Cantaloupe fruit weight was also reduced 21% and 10% when either herbicide was applied at the 1/75 rate 54 or 31 DBH, respectively. Residue analysis noted applications made closer to harvest were more likely to be detectable in fruit than earlier applications. In cucumber, dicamba was detected at both rates when applied 7 DBH, whereas in cantaloupe, it was detected at both rates when applied 18 or 31 DBH in 2016 and at the 1/75 rate applied 18 or 31 DBH in 2014. Detectable amounts of 2,4-D were not observed in cucumber but were detected in cantaloupe when applied at either rate 18 or 31 DBH. Although early-season injury will more likely reduce cucumber or cantaloupe yields, the quantity of herbicide residue detected will be most influenced by the time interval between the off-target incident and sampling.
Making a Place for the Next Generation of Geoscientists
Authors: Li Miling , Sutfin Nicholas , Christie Margaret , Neelam Maheshwari , Bradley James
Published: November 2020

Early-career scientists from the AGU Mentoring Network discuss how the global pandemic has exacerbated long-standing issues with the availability of positions in and the diversity of the geosciences.
Author Correction: The Impact of Bt Corn on Aflatoxin-Related Insurance Claims in the United States
Authors: Yu Jina , Hennessy David A. , Wu Felicia
Published: November 2020

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Imaging findings of pulmonary manifestations of chronic granulomatous disease in a large single center from Shanghai, China (1999–2018)
Authors: Yao Qiong , Zhou Qin-hua , Shen Quan-li , Qiao Zhong-wei , Wang Xiao-chuan , Hu Xi-hong
Published: November 2020

Chronic granulomatous disease (CGD) is characterized by recurrent infections and granuloma formation in multiple organs, especially the lung. We aimed to investigate pulmonary manifestations by computed tomography (CT). In total, 100 patients with 117 episodes of pulmonary infection were included. Chest CT scans of every episode were analyzed. Random nodules were the most common findings (79.49%), followed by ground-grass opacities (74.36%), focal consolidations (62.39%), and masses (59.83%). Cavities (12.82%) and multiple small abscesses (17.09%) could be found in the consolidations and masses. CT revealed interstitial pneumonia with tree-in-bud opacities (17.09%), interlobular septal thickening (23.08%) and emphysema (35.04%), which were more severe in the bilateral upper lobes. Mediastinal and hilar lymphadenopathy (78.63%) and axillary lymphadenopathy (65.81%) were common. Fungal infection (n = 27) was the most common and presented with multiple nodules and masses. Approximately 1/4 of fungal infections had interstitial pneumonia. In Staphylococcus aureus (n = 6) and Klebsiella pneumoniae (n = 3) infections, large areas of consolidation were common. In tuberculosis infection, the pulmonary infections were more severe and complex. For Bacillus Calmette-Guérin disease, left-sided axillary lymphadenopathy was a characteristic manifestation. CT images of CGD demonstrated variable pulmonary abnormalities. The main infectious organisms have unique imaging features.
Pelvic bone morphometric analysis in the dugong (Dugong dugon)
Authors: Nganvongpanit Korakot , Cherdsukjai Phaothep , Boonsri Burin , Buddhachat Kittisak , Kaewmong Patcharaporn , Kittiwattanawong Kongkiat
Published: November 2020

The dugong (Dugong dugon Müller) is recognized as an endangered marine mammal. There is limited available anatomical data on the dugong’s skeletal system, while what is available has not been well established due to the limited number of archived samples and limited access to them. Importantly, there are certain key questions that should be answered when examining the bones and/or remains of animals such as; what kind of bone is it?; what species does it belong to?; what sex was the animal?; how old was the animal? or how big was it?, etc. In this study, we have focused on the pelvic bone of the dugong by asserting the hypothesis that pelvic bone morphology is related to age, sex, and body size. Here, we have established certain morphometric data encompassing 8 parameters and 5 indexes to analyze the morphology of the pelvic bones obtained from 88 specimens (45 dugongs). We will present three main findings: (1) the pelvic bone in mature male subjects is larger than it is in female subjects, (2) a high rate of accuracy can be established for sex identification using morphometric data obtained from the pelvic bone, and (3) the pelvic bone has the highest degree of correlation with body length, followed by body weight and age. Notably, the important data on the pelvic bone of the dugong acquired in this study can be reliable and extremely useful in sex identification and body size estimation.
Plasma-enhanced direct conversion of CO2 to CO over oxygen-deficient Mo-doped CeO2
Authors: Wang Li , Du Xiaomin , Yi Yanhui , Wang Hongyang , Gul Masaud , Zhu Yimin , Tu Xin
Published: November 2020

Oxygen-deficient Mo-doped CeO2 showed significantly higher CO2 conversion compared to pure CeO2 in the plasma splitting of CO2.
A polyoxometalate-encapsulated nanocage cluster organic framework built from {Cu4P2} units and its efficient bifunctional electrochemical performance
Authors: Li Shaobin , Tan Xiaoguo , Yue Ming , Zhang Li , Chai Dongfeng , Wang Wendi , Pan Hong , Fan Linlin , Zhao Chunyan
Published: November 2020

The first polyoxometalate-encapsulated twenty-four-nucleus organophosphorus-copper nanocage cluster organic framework has been constructed and it is shown to exhibit highly efficient bifunctional electrochemical performance.
Supramolecular linear coordination polymers of human serum albumin and haemoglobin
Authors: Adachi Ryo , Suzuki Shun , Mitsuda Tatsuya , Morita Yoshitsugu , Komatsu Teruyuki
Published: November 2020

Human serum albumin and human haemoglobin having two-terpyridyl arms were readily polymerized via a bis(terpyridyl)–Fe2+ complex to generate watersoluble, uniform, and linear nanofibres.
Anomalous inclusion of chloride ions in ethylenediammonium lead iodide turns 1D non-perovskite into a 2D perovskite structure
Authors: Fazayeli Monireh , Khatamian Maasoumeh , Cruciani Giuseppe
Published: November 2020

A 2D ethylenediammonium lead iodide perovskite structure can form just by adding some chloride ions into the solution.
Structural and chemical interplay between nano-active and encapsulation materials in a core–shell SnO2@MXene lithium ion anode system
Authors: Wang Peiran , Yan Yuantao , Cheng Chi , Zhang Weimin , Zhou Dengke , Li Linsen , Yang Xiaowei , Liao Xiao-Zhen , Ma Zi-Feng , He Yu-Shi
Published: November 2020

Structural and chemical interplay between nano-active and encapsulation materials in a core–shell SnO2@MXene lithium ion anode system was investigated in detail.
Relationship between structural and dielectric properties of Zn-substituted Ba5CaTi2−xZnxNb8O30 tetragonal tungsten bronze
Authors: Bendahhou Amine , Marchet Pascal , El-Houssaine Ablouh , El Barkany Soufian , Abou-Salama Mohamed
Published: November 2020

Ba5CaTi2−xZnxNb8O30 ceramics (x = 0, 0.04, and 0.08) were synthesized by a conventional solid-state reaction method at 1300 °C for 6 hours.
Mechanistic insights into the optical limiting performance of carbonaceous nanomaterials embedded with core–shell type graphite encapsulated Co nanoparticles
Authors: Kumar Rajeev , Kumar Ajay , Verma Nancy , Philip Reji , Sahoo Balaram
Published: November 2020

Globular amorphous carbonaceous materials embedded with graphite encapsulated metallic Co-nanoparticles with a high degree of crystallinity are synthesized by pyrolysis and demonstrated as excellent candidates for optical limiters.
Anchoring a bow-shaped boron single chain in binary Be6B7− cluster: hybrid octagonal ring, multifold π/σ aromaticity, and dual electronic transmutation
Authors: Feng Lin-Yan , Wang Kang , Zhai Hua-Jin
Published: November 2020

A bow-shaped B7 single chain motif is stabilized in binary Be6B7− cluster, which undergoes dual electronic transmutation, being governed by multifold 1σ/10π/6σ/1σ aromaticity.
Investigating the influence of relativistic effects on absorption spectra for platinum complexes with light-activated activity against cancer cells
Authors: Creutzberg Joel , Hedegård Erik Donovan
Published: November 2020

We report the first systematic investigation of relativistic effects on the UV-vis spectra of two prototype complexes for so-called photo-activated chemotherapy (PACT), trans–trans–trans-[Pt(N3)2(OH)2(NH3)2] and cis–trans–cis-[Pt(N3)2(OH)2(NH3)2].
A 3-dimensional microfluidic platform for modeling human extravillous trophoblast invasion and toxicological screening
Authors: Pu Yong , Gingrich Jeremy , Veiga-Lopez Almudena
Published: November 2020

A novel 3D microfluidic system for placenta trophoblast cell invasion and cell-to-cell interaction studies under dynamic environment conditions.
Decoupled ion mobility in nano-confined ionic plastic crystal
Authors: Zhu Haijin , Grzelak Aleksandra , Yunis Ruhamah , Martín Jaime , Forsyth Maria
Published: November 2020

Nano-confinement can selectively change the rotational and translational motion of diethylmethylisobutylphosphonium cation, whereas leaving the hexafluorophosphate anion less affected.
Binding motif of ebselen in solution: chalcogen and hydrogen bonds team up
Authors: Daolio Andrea , Scilabra Patrick , Di Pietro Maria Enrica , Resnati Chiara , Rissanen Kari , Resnati Giuseppe
Published: November 2020

Ebselen, a compound active against SARS-CoV-2, forms a bifurcated supramolecular synthon thanks to chalcogen bond and hydrogen bond cooperation.
Broadband yellow light emitting performance based on zero-dimensional hybrid lead bromide trimers
Authors: Sun Xing-Yu , Zhang Wei-Feng , Pan Hong-Mei , Ma Yue-Yu , Jing Zhi-Hong
Published: November 2020

Two new zero-dimensional organic–inorganic hybrid lead halides based on linear [Pb3Br12]6− trimers display broadband yellow light emissions with high photoluminescence quantum yields, exhibiting potential in the fabrications of white-light emitting diodes.
A new salamo-based colorimetric and fluorescent turn-on sensor with aggregation-induced emission for the rapid and highly sensitive detection of cyanide in real samples
Authors: Chen Zhuang-Zhuang , Li Ruo-Yu , Zhang Wen-Ze , Zhang Yang , Dong Wen-Kui
Published: November 2020

A new, simple, and easy-to-manufacture highly selective and sensitive dual-mode sensorA1with the aggregation-induced emission properties is used for CN−colorimetric and fluorescence detection.
Mitochondrial translation inhibition triggers ATF4 activation, leading to integrated stress response but not to mitochondrial unfolded protein response
Authors: Sasaki Katsuhiko , Uchiumi Takeshi , Toshima Takahiro , Yagi Mikako , Do Yura , Hirai Haruka , Igami Ko , Gotoh Kazuhito , Kang Dongchon
Published: November 2020

Mitochondrial–nuclear communication, known as retrograde signaling, is important for regulating nuclear gene expression in response to mitochondrial dysfunction. Previously, we have found that p32/C1qbp-deficient mice, which have a mitochondrial translation defect, show endoplasmic reticulum (ER) stress response and integrated stress response (ISR) gene expression in the heart and brain. However, the mechanism by which mitochondrial translation inhibition elicits these responses is not clear. Among the transcription factors that respond to mitochondrial stress, activating transcription factor 4 (ATF4) is a key transcription factor in the ISR. Herein, chloramphenicol (CAP), which inhibits mitochondrial DNA (mtDNA)-encoded protein expression, induced eukaryotic initiation factor 2 α subunit (eIF2α) phosphorylation and ATF4 induction, leading to ISR gene expression. However, the expression of the mitochondrial unfolded protein response (mtUPR) genes, which has been shown in Caenorhabditis elegans, was not induced. Short hairpin RNA-based knockdown of ATF4 markedly inhibited the CAP-induced ISR gene expression. We also observed by ChIP analysis that induced ATF4 bound to the promoter region of several ISR genes, suggesting that mitochondrial translation inhibition induces ISR gene expression through ATF4 activation. In the present study, we showed that mitochondrial translation inhibition induced the ISR through ATF4 activation rather than the mtUPR.
Increasing Pluralistic Education Through Cross-Cultural Interprogram Collaboration
Authors: Franca Maria Claudia , Boyer Valerie , Pegoraro-Krook Maria Inês
Published: November 2020

Purpose

Achieving professional competence requires a wide-ranging approach of preparation through education. Instructional approaches to advance proper training of future clinicians should contain an array of academic and field experiences that translate into clinical competency; this includes immersion in varied sceneries and exposure to different contexts. For that end, it is crucial to embrace the most current societal paradigms.

Conclusions

This tutorial describes activities devised to promote higher education pursuits through intercontinental partnership, using recent and ongoing cooperation between two universities in different countries as a backdrop for reflections. The ultimate goal of this tutorial is to summarize collaborative efforts in order to promote similar pursuits. Activities devised to foster international scholastic partnerships aimed at increased professional competence are described.
Value-Based Health Care: Adjusting Speech-Language Pathology Practice to Fit the Model
Authors: Swigert Nancy B. , Wright Ashley
Published: November 2020

Purpose

The climate of health care is changing, and reimbursement is evolving into a value-based system. Facilities are pressed to be more fiscally responsible with their resources. The notion of “doing more with less” is becoming a predominant theme across settings, and speech-language pathologists (SLPs) must adjust practice models to prove their value to both payers and customers. The Centers for Medicare & Medicaid Services is moving away from a fee-for-service model, and reimbursement is being based on the quality and safety of services, not the quantity. This article will examine key components of value-based care, including how SLPs can provide their services effectively and efficiently and analyze the value-based reimbursement model in their setting to identify ways to demonstrate their value beyond direct service provision.

Conclusions

Effectiveness and efficiency are the key components of a value-based system. SLPs must stay abreast of evidence-based practice and use appropriate measures to determine the effectiveness of their interventions. They must provide the right service to the right patient with the right frequency and intensity. They must also ensure they are practicing at the top of the license to reduce/eliminate any activities that are not a skilled service, which decrease efficiency. A pivotal component is patient self-management, which places responsibility on patients and caregivers to work toward goals between sessions. SLPs can help promote the value of their services by working collaboratively with other disciplines to improve patient outcomes as well as the fiscal well-being of the facilities in which they serve.
Interprofessional Collaboration to Promote Culturally Engaged and Strengths-Based Practice
Authors: Ellis Erica , Kubalanza Mary , Simon-Cereijido Gabriela , Munger Ashley , Fuligni Allison Sidle
Published: November 2020

Purpose

To effectively prepare students to engage in interprofessional practice, a number of Communication Disorders (COMD) programs are designing new courses and creating additional opportunities to develop the interprofessional competencies that will support future student success in health and education-related fields. The ECHO (Educational Community Health Outreach) program is one example of how the Rongxiang Xu College of Health and Human Services at California State University, Los Angeles, has begun to create these opportunities. The ultimate goal of the ECHO project is to increase both access to and continuity of oral health care across communities in the greater Los Angeles area.

Method

We describe this innovative interdisciplinary training program within the context of current interprofessional education models. First, we describe the program and its development. Second, we describe how COMD students benefit from the training program. Third, we examine how students from other disciplines experience benefits related to interprofessional education and COMD. Fourth, we provide reflections and insights from COMD faculty who participated in the project.

Conclusions

The ECHO program has great potential for continuing to build innovative clinical training opportunities for students with the inclusion of Child and Family Studies, Public Health, Nursing, and Nutrition departments. These partnerships push beyond the norm of disciplines often used in collaborative efforts in Communication Sciences and Disorders. Additionally, the training students received with ECHO incorporates not only interprofessional education but also relevant and important aspects of diversity and inclusion, as well as strengths-based practices.
Enhancement of microstructure uniformity and grain refining efficiency of Al-5Ti-1B alloy via powder extrusion
Authors: Wang Shuncheng , Huang Huilan , Zhang Zhibo , Zheng Kaihong
Published: November 2020

Microstructure uniformity and grain refining efficiency of Al-5Ti-1B alloy rod prepared by powder extruded process and continuous casting and rolling process are investigated in detail by X ray diffractometer, scanning electron microscope and electron probe. It is found that TiB2 and TiAl3 particles are uniformly distributed in the powder extruded Al-5Ti-1B alloy via gas atomization and hot extrusion process. The samples with 0.2% powder extruded Al-5Ti-1B alloy rod holding for 2 min consist of equiaxed grains with an average diameter of 183 µm. Even the holding time extended to 180 min, the average diameter is still stable (229 µm). Al-5Ti-1B alloy rod prepared by the powder extruded process presents better grain refinement and stronger resistance to grain coarsening.
Interopérabilité et automatisme dans les etudes du Bâtiment
Authors: Billon Roland , Fasse Isabelle , Parinaud Thierry
Published: November 2020

Les professionnels constatent des difficultés dans l’exploitation de la norme ISO dite « IFC » d’échange de données du Bâtiment, ainsi que dans la maquette numérique des projets (BIM)telle qu’elle existe aujourd’hui. Deux disciplines qui selon les auteurs sont devenues inséparables dans la conception des ouvrages. Ajouter de l’information numérique dans cette maquette ne résout pas l’essentiel attendu : son partage et sa synthèse2 entre les métiers. Pour relever le défi d’une veritable interopérabilité dans les échanges de données entre métiers, qui supposent des procédures automatisées, les auteurs imaginent un outil logiciel.
De quelle nature sera l'esquisse ?
Authors: Mortamais Elizabeth
Published: November 2020

Nous revenons sur le sujet de l'Esquisse comme moment particulier de la conception, tel que questionné dans notre communication de SCAN'05, en 2005. Il s'agit ici d'entrevoir quelles mutations sont en train de se produire, ou vont se produire dans le processus de génération du projet au stade de l'esquisse dès l'instant où des outils numériques très performants en terme de calculs et d'intégration des données, de generation de forme et de présentation immédiate (de type Réalité Virtuelle) se diffusent de plus en plus largement ou vont devenir accessibles à brève échéance. L'aisance à terme, de l'usage de telles outils va-t-elle modifier l'interaction entre le ou les concepteurs et leurs productions qu'ils pourront éprouver en situation d'énaction ? Le panel d'acteurs du projet va-t-il muter notamment avec l'avènement d'outils de ce type, disponibles pour le grand public ? Le processus de conception en sera-t-il modifié ? La nature de l'esquisse comme stade initial fondamental en sera-t-elle changée ?
GéoÉdu-JEU : l’éducation du Design comme un « jeu GÉO-spatial de l’inconnu » ou « the game of the unknown »
Authors: Wacta Christine
Published: November 2020

GéoÉdu-JEU explore l’enseignement de d’architecture à travers la gamification et GeoDesign2 , il intègre dans l’apprentissage une composante ludique et l’approche constructiviste cognitive individuelle-collective où les développements des systèmes de pensée et compréhension sont alimentés par l’environnement ; ainsi, les efforts de l’individu pour se comprendre ainsi que son environnement entraînent un développement cognitif. GéoÉdu-JEU répond aux besoins de l’étudiant(e) contemporain(e) dans l’utilisation des appareils mobiles-personnels qui sont ses principales formes de communication et de gestion de contenu en dehors du campus. Le « jeu de l’inconnu» est une stratégie de ce travail qui consiste à partir de zéro pour développer un argument contextuel et une formulation de problèmes informés et géolocalisés. Alors que la méthode classique d’enseignement se base sur le connu (projet-client-site), GéoÉdu-JEU définit la compétition physique, mentale menée dans un contexte psycho-géographique selon les mécanismes du jeu. Car, le processus heuristique de pratique architecturale ressemble au jeu dans sa résolution de problèmes spatiaux, elle opère dans des structures flexibles orientées par le concepteur, gère l'intuition, les incertitudes et s'appuie sur des règles. Si l'architecture ne saurait se faire sans analyse géospatiale, elle a pourtant du mal à se saisir des outils du contemporain, qui ont fait émerger dans le champ des sciences de la complexité une discipline nouvelle : la Géo-Spatialisation.
Fachübergreifende Etablierung eines Kindernotfallblatts
Authors: Morgenthal Uwe , Lembcke Thomas , Soukup Jens
Published: November 2020

„Wir bekommen einen Zugang aus der Notaufnahme – ein Kind, zwei Jahre alt, nach einem Verkehrsunfall …“ So oder ähnlich lauten die Worte, die Stress auslösen. Die meisten Kollegen hoffen, dass der Kelch an ihnen vorübergeht und sie nicht mit der Betreuung dieses Kindes beauftragt werden. In solchen Situationen erweisen sich digitale kognitive Hilfsmittel als wahre Retter in der Not.
Zwischen den Faktoren Zeit und Sicherheit – Reanimation bei COVID-19
Authors: Schweitzer Carina , Kleindieck Kristin
Published: November 2020

Die Studienlage zur intensivmedizinischen Betreuung von COVID-19-Patienten ist nicht eindeutig geklärt. Wie kann es gelingen, trotzdem Handlungssicherheit im intensivmedizinischen Setting zu gewährleisten und gleichzeitig zu verhindern, dass das medizinische Personal sich infiziert?
Intrahospitaler Transport kritisch kranker Patienten
Authors: Lanfermann Christian
Published: November 2020

Patiententransporte zur Diagnostik oder in den OP sind Alltag auf einer Intensivstation. Jedoch ist der Transport kritisch kranker, beatmeter Patienten eine hochkomplexe und zeitaufwendige Aufgabe für das betreuende Team. Die Herausforderung besteht in der Wahrung der Patientensicherheit unter der kontinuierlichen Weiterführung bestehender Überwachungs- und Therapiemaßnahmen. Der folgende Beitrag gibt einen Überblick über Transporttraumata und die Möglichkeiten, diese zu reduzieren.
Recent Advances in One-Pot Enyne Metathesis Processes for the Preparation of Biologically and Medicinally Relevant Compounds
Authors: Serra Massimo , Bernardi Eric , Colombo Lino
Published: November 2020

Enyne metathesis reactions are powerful tools for the preparation of a wide range of synthetic and natural chemical substances with increasing efficiency and environmental sustainability. The driving force of the reaction is the formation of a stable conjugated system, i.e., a diene, which through further functionalization steps can be used for the construction of skeletally complex molecular architectures. These concepts are exploited to design cascade reaction sequences, where multiple rings can be formed in a one-pot fashion by combining metathetic protocols with various chemical transformations. The strong correlation between synthetic organic chemistry and medicinal chemistry prompted us to review the most notable approaches for the synthesis of biologically relevant compounds via enyne metathesis-based one-pot processes. With the aim to provide a modern and practical overview, by taking into consideration the scientific literature on this topic, we have focused the majority of our attention on the research performed in the last decade. This review covers the literature from 2003 to 2020.

1 Introduction

2 Ethylene-Mediated Processes

3 RCEYM/CM and CEYM/RCM Processes

4 Enyne Metathesis/Diels–Alder-Based Processes

5 RCM of Dienynes

6 RCM of Tethered Dienynes

7 Relay Metathesis

8 Ring-Rearrangement Metathesis

9 RCEYM/Transition-Metal-Catalyzed C–C Bond-Forming Processes

10 Conclusions

11 List of Acronyms
Magnetic cusp confinement in low-β plasmas revisited
Authors: Jiang Y. , Fubiani G. , Garrigues L. , Boeuf J. P.
Published: November 2020

Magnetic cusps have been used for more than 50 years to limit charged particle losses to the walls and confine the plasma in a large variety of plasma sources or ion sources. Quantification of the effective loss area has been the subject of many experimental as well as theoretical investigations in the 1970s–1990s. In spite of this effort, there is no fully reliable expression of the effective wall loss as a function of cusp magnetic field, electron temperature, ion mass, gas pressure, etc. We describe in this paper a first attempt at obtaining scaling laws for the effective loss width of magnetic cusps based on two-dimensional particle-in-cell Monte Carlo collision simulations. The results show that the calculated leak width follows a 1/B scaling in the collisionless low B limit, is approximately proportional to the hybrid gyroradius with an ion velocity equal to the Bohm velocity, and is proportional to the square root of gas pressure in the collisional limit.
Rail-gap switch with a multistep high-voltage triggering system
Authors: Chang Po-Yu , Hsieh Chih-Jui , Huang Mei-Feng , Jheng Ming-Cheng , Lin Yen-Cheng , Liu Jia-Kai , Yang Sheng-Hua
Published: November 2020

A rail-gap switch with a multistep triggering system was developed. The rail-gap switch consisted of two rail-like electrodes and a knife-edge electrode parallel to each other. It was assembled from many pieces and filled with unpressurized-flowing dry air. Good alignments between all electrodes were achieved by using a special jig and the knife-edge electrode as the spatial reference. Furthermore, to trigger the rail-gap switch, a multistep triggering system was used. The triggering system consisted of three components: an optical trigger-pulse generator, a slow high-voltage trigger-pulse generator using an ignition coil for a car, and finally, a fast high-voltage trigger-pulse generator using a three-stage Marx generator. The triggering system generated a negative high-voltage trigger pulse of less than −40 kV with a falling speed of −6.6 ± 0.4 kV/ns. The falling speed was fast enough to initiate multichannel discharges in the rail-gap switch. Finally, the rail-gap switch was tested using a test bench consisting of a 0.5-μF capacitor bank charged to 20 kV. The rail-gap switch was triggered by the multistep triggering system robustly with a delay of 180 ns. The delay between the time, when the peak current of the test bench occurred, and the trigger pulse was 890 ns with a jitter of 20 ns, i.e., ∼2% uncertainty in time. The inductance of the rail-gap switch was ∼80 nH obtained from the discharge tests. The rail-gap switch with the multistep high-voltage triggering system is suitable for any pulsed-power systems with current rise times in the order of 1 µs.
Effect of different superimposed structures on the transparent electromagnetic interference shielding performance of graphene
Authors: Shi Kai , Su Junhong , Liang Haifeng , Hu Kai
Published: November 2020

The effect of different superimposed structures on the transparent electromagnetic interference (EMI) shielding performance of graphene is reported. The average optical transmittance of a graphene/quartz sample with different superimposed structures in the Vis-near-infrared spectrum (400–2400 nm) is almost the same (84%). The EMI shielding efficiency (EMI SE) of the two samples after superposition is 4.85–3.96 dB, which has been greatly improved compared to the single sample. The EMI SE of the backward superposition is 0.5–0.2 dB larger than the interval superposition. The EMI SE of the interval superposition is 0.8–0.2 dB larger than the forward superposition. The backward superposition of graphene can absorb 55% of the electromagnetic waves, reflect 10%, and only 35% of the electromagnetic waves pass. We envision that graphene can obtain high EMI SE through different superimposed structures in the theoretical research and applications.
Temperature of metal wires for nanosecond and microsecond electrical explosions in vacuum
Authors: Sarkisov G. S.
Published: November 2020

Experiments show an inverse correlation between temperature and heating time for the electrical explosion of thin metal wires in vacuum. Faster heating of the wire results in higher energy release in a short time, while slow heating lasts longer but releases less energy before breakdown. Breakdown is a natural barrier to the direct release of Joule energy and an increase in the metal temperature to an abnormally high value. An increase in the current rate from 0.07 to 170 A/ns leads to a decrease in the heating time from 5 μs to 5 ns and an increase in the wire temperature from 450 K to 4000 K before the voltage breakdown. This inverse correlation between the heating time and the temperature of the wire in a vacuum can be explained by the inertia of evaporation of the hydrocarbon impurity from the surface of the hot metal.
Isotropic conduction and negative photoconduction in ultrathin PtSe2 films
Authors: Urban Francesca , Gity Farzan , Hurley Paul K. , McEvoy Niall , Di Bartolomeo Antonio
Published: November 2020

PtS e 2 ultrathin films are used as the channel of back-gated field-effect transistors that are investigated at different temperatures and under super-continuous white laser irradiation. The temperature-dependent behavior confirms the semiconducting nature of multilayer PtSe2, with p-type conduction, a hole field-effect mobility up to 40 cm2 V−1 s−1, and significant gate modulation. Electrical conduction measured along different directions shows isotropic transport. A reduction of PtSe2 channel conductance is observed under exposure to light. Such a negative photoconductivity is explained by a photogating effect caused by photo-charge accumulation in SiO2 and at the Si/SiO2 interface.
A perspective on nanoscale pattern formation at surfaces by ion-beam irradiation
Authors: Cuerno R. , Kim J.-S.
Published: November 2020

The formation of periodic patterns on the surfaces of many solid materials undergoing ion-beam irradiation has long been known. The advent of high resolution characterization techniques elucidated the nanoscopic traits of this self-organization process, enabling a wide range of applications for the nanostructures thus produced, from optoelectronic to biomedical. Meanwhile, full theoretical understanding of the technique has been challenged by its multiscale nature, whereby the external perturbation implemented by the ion beam acts at a much slower rate (typically, one ion arrives per square-nm every second) than the microscopic processes, like collision cascades and material transport, which try to relax such external perturbations (collision cascades or surface diffusion attempts usually relax after a few picoseconds). Here, we present a Perspective on the main developments that have led to the current understanding of nanoscale pattern formation at surfaces by ion-beam irradiation, from the points of view of experiments, applications, and theory, and offer an outlook on future steps that may eventually facilitate full harnessing of such a versatile avenue to materials nanostructuring.
Nonideal mixing effects in warm dense matter studied with first-principles computer simulations
Authors: Militzer Burkhard , González-Cataldo Felipe , Zhang Shuai , Whitley Heather D. , Swift Damian C. , Millot Marius
Published: November 2020

We study nonideal mixing effects in the regime of warm dense matter (WDM) by computing the shock Hugoniot curves of BN, MgO, and MgSiO3. First, we derive these curves from the equations of state (EOS) of the fully interacting systems, which were obtained using a combination of path integral Monte Carlo calculations at high temperature and density functional molecular dynamics simulations at lower temperatures. We then use the ideal mixing approximation at constant pressure and temperature to rederive these Hugoniot curves from the EOS tables of the individual elements. We find that the linear mixing approximation works remarkably well at temperatures above ∼2 × 105 K, where the shock compression ratio exceeds ∼3.2. The shape of the Hugoniot curve of each compound is well reproduced. Regions of increased shock compression, which emerge because of the ionization of L and K shell electrons, are well represented, and the maximum compression ratio of the Hugoniot curves is reproduced with high precision. Some deviations are seen near the onset of the L shell ionization regime, where ionization equilibrium in the fully interacting system cannot be well reproduced by the ideal mixing approximation. This approximation also breaks down at lower temperatures, where chemical bonds play an increasingly important role. However, the results imply that the equilibrium properties of binary and ternary mixtures in the regime of WDM can be derived from the EOS tables of the individual elements. This significantly simplifies the characterization of binary and ternary mixtures in the WDM and plasma phases, which otherwise requires large numbers of more computationally expensive first-principles computer simulations.
Accurate characterization of tip-induced potential using electron interferometry
Authors: Iordanescu A. , Toussaint S. , Bachelier G. , Fallahi S. , Gardner C. G. , Manfra M. J. , Hackens B. , Brun B.
Published: November 2020

Using the tip of a scanning probe microscope as a local electrostatic gate gives access to real-space information on electrostatics as well as charge transport at the nanoscale, provided that the tip-induced electrostatic potential is well known. Here, we focus on the accurate characterization of the tip potential, in a regime where the tip locally depletes a two-dimensional electron gas (2DEG) hosted in a semiconductor heterostructure. Scanning the tip in the vicinity of a quantum point contact defined in the 2DEG, we observe Fabry–Pérot interference fringes at low temperature in maps of the device conductance. We exploit the evolution of these fringes with the tip voltage to measure the change in the depletion radius by electron interferometry. We find that a semi-classical finite-element self-consistent model taking into account the conical shape of the tip reaches a faithful correspondence with the experimental data.
Effect of argon and oxygen gas concentration on mode transition and negative ion production in helicon discharge
Authors: Sharma N. , Chakraborty M. , Saha P. K. , Mukherjee A. , Neog N. K. , Bandyopadhyay M.
Published: November 2020

In this paper, the effect of mixing of argon and oxygen gas on the mode transition and negative ion production in the helicon discharge is investigated. In the source chamber of the experimental setup, argon–oxygen gas mixture plasma is produced by applying RF power from 100 W to 2000 W at an applied magnetic field of 0.03 T. In this experiment, the total flow rate is kept at 200 SCCM, corresponding to the working pressure of 4–5 × 10−1 Pa. The mode transition to helicon discharge is investigated by varying the concentration of these two gases. To the best of our knowledge, the literature survey indicates this to be the first study of the influence of the mixing of oxygen–argon gas on the mode transition from the inductive to the helicon mode. It is observed that an increase in the concentration of oxygen gas in the discharge shifts mode transition toward higher RF power values, indicating the influence of the nature of the working gas on the transition to the inductive as well as to the helicon mode. The variation of the electron density and temperature is explained in terms of particle and power balance equation. In the source and in the downstream expansion chamber, the effect of the concentration of argon gas on the negative ion production in oxygen discharge is also studied, and the results are explained in terms of various reactions involved in the production and loss of negative ions.