bluuebunny/crossref_metadata_2025 huggingface dataset:
Ligand‐induced transition in conformations of vicinal cysteine disulfides in proteins
Authors: Reddy K. Kasi Amarnath , Jayashree Muddagoni , Govindu Panchada Ch V. , Gowd Konkallu Hanumae
Published: December 2020

Vicinal cysteine disulfides are thought to be associated with specific conformations of cysteine disulfides due to the restricted rotation of single bonds in an eight‐membered cyclic disulfide loop. Conformations of vicinal cysteine disulfides are analyzed using χ1, χ2, χ3, χ2', χ1' torsion angles in the crystal structures of proteins retrieved from Protein Data Bank (PDB). 85% of vicinal disulfides have (+, −)LHStaple conformation with trans configuration of the peptide bond and 9% have (−, −)RHStaple conformation with cis configured peptide bond. Conformational analysis of dipeptide Cys‐Cys vicinal disulfide by density functional theory (DFT) further supported (+, −)LHStaple, (−, −)RHStaple, and (+, +)RHStaple as the preferred conformations of vicinal disulfides. Interestingly, the rare conformations of vicinal disulfides are observed in the ligand‐bound forms of proteins and have higher disulfide strain energy. Conformations of vicinal disulfides in palmitoyl protein thioesterase 1, AChBP, and α7 nicotinic receptor are changed from preferred (+, −)LHStaple to rare (+, −)AntiLHHook/(+, −)AntiRHHook/(+, +)RHStaple conformation due to binding of ligands. Surprisingly, ligands are proximal to the vicinal disulfides in protein complexes that exhibited rare conformations of vicinal disulfides. The report has identified (+, −) LHStaple/(−, −) RHStaple as the hallmark conformations of vicinal disulfides and unraveled ligand‐induced transition in conformations of vicinal cysteine disulfides in proteins.
Ca2+ as cofactor of the mitochondrial H+‐translocating F1FO‐ATP(hydrol)ase
Authors: Nesci Salvatore , Pagliarani Alessandra
Published: December 2020

The mitochondrial F1FO‐ATPase in the presence of the natural cofactor Mg2+ acts as the enzyme of life by synthesizing ATP, but it can also hydrolyze ATP to pump H+. Interestingly, Mg2+ can be replaced by Ca2+, but only to sustain ATP hydrolysis and not ATP synthesis. When Ca2+ inserts in F1, the torque generation built by the chemomechanical coupling between F1 and the rotating central stalk was reported as unable to drive the transmembrane H+ flux within FO. However, the failed H+ translocation is not consistent with the oligomycin‐sensitivity of the Ca2+‐dependent F1FO‐ATP(hydrol)ase. New enzyme roles in mitochondrial energy transduction are suggested by recent advances. Accordingly, the structural F1FO‐ATPase distortion driven by ATP hydrolysis sustained by Ca2+ is consistent with the permeability transition pore signal propagation pathway. The Ca2+‐activated F1FO‐ATPase, by forming the pore, may contribute to dissipate the transmembrane H+ gradient created by the same enzyme complex.
Benchmarking anisotropic polarizabilities for 14 (hetero)‐aromatic molecules at RPA, RPA(D), HRPA, HRPA(D), SOPPA, SOPPA(CC2), SOPPA(CCSD), CC2, CCSD and CC3 levels
Authors: Jørgensen Maria W. , Sauer Stephan P. A.
Published: December 2020

A benchmark of anisotropic polarizabilities has been carried out for 14 (hetero)‐aromatic molecules using the methods: RPA, RPA(D), HRPA, HRPA(D), SOPPA, SOPPA(CC2), SOPPA(CCSD), CC2, CCSD and CC3. While this benchmark, to a large extend, shows similar tendencies as found for isotropic polarizabilities, it also reveals some differences between isotropic and anisotropic polarizabilities. CCSD is found to be the method performing closest to CC3 as it also was for isotropic polarizabilities. For static anisotropic polarizabilities SOPPA(CCSD) performs incredibly close to CCSD, however, the less demanding HRPA(D) follows shortly after in precision. For dynamic anisotropic polarizabilities SOPPA(CCSD) is again the method least deviating from CC3, beside CCSD, but its SD is worse than for RPA, which gives results only slightly more deviating from the CC3 results than SOPPA(CCSD). While the HRPA model is seen to perform incomparably worse than any of the other methods, the simpler RPA is on the other hand thus performing notably well. The finding of this good performance of the relatively simpler and cheaper methods, RPA and HRPA(D), permits calculation of much larger systems without sacrificing the quality of the calculation.
Topological indices and QSPR/QSAR analysis of some antiviral drugs being investigated for the treatment of COVID‐19 patients
Authors: Kirmani Syed Ajaz K. , Ali Parvez , Azam Faizul
Published: December 2020

The spread of novel virus SARS‐CoV‐2, well known as COVID‐19 has become a major health issue currently which has turned up to a pandemic worldwide. The treatment recommendations are variable. Lack of appropriate medication has worsened the disease. On the basis of prior research, scientists are testing drugs based on medical therapies for SARS and MERS. Many drugs which include lopinavir, ritonavir and thalidomide are listed in the new recommendations. A topological index is a type of molecular descriptor that simply defines numerical values associated with the molecular structure of a compound that is effectively used in modeling many physicochemical properties in numerous quantitative structure–property/activity relationship (QSPR/QSAR) studies. In this study, several degree‐based and neighborhood degree sum‐based topological indices for several antiviral drugs were investigated by using a M‐polynomial and neighborhood M‐polynomial methods. In addition, a QSPR was established between the various topological indices and various physicochemical properties of these antiviral drugs along with remdesivir, chloroquine, hydroxychloroquine and theaflavin was performed in order to assess the efficacy of the calculated topological indices. The obtained results reveal that topological indices under study have strong correlation with the physicochemical characteristics of the potential antiviral drugs. A biological activity (pIC50) of these compounds were also investigated by using multiple linear regressions (MLR) analysis.
Extremal Mostar indices of tree‐like polyphenyls
Authors: Deng Kecai , Li Shuchao
Published: December 2020

Given a graph G, the Mostar index Mo(G) is the sum of absolute values of the differences between nu(e) and nv(e) over all edges e = uv of G, where nu(e) and nv(e) are, respectively, the number of vertices of G lying closer to u than to v and the number of vertices of G lying closer to v than to u. A tree‐like polyphenyl is a polycyclic aromatic hydrocarbon consisting of benzene rings, whose chemical graph will tend to a tree after contracting each hexagon into a vertex (the tree is called a contracted tree). A polyphenyl chain is a tree‐like polyphenyl whose contracted tree is a path. In this paper, those polyphenyl chains with n benzene rings having the least, the second least, the greatest and the second greatest Mostar indices are determined, respectively. Those tree‐like polyphenyls with n benzene rings having the least and the second least Mostar indices are also identified. What is more, some properties of those tree‐like polyphenyls with n benzene rings having the greatest Mostar index are obtained. At the end we state some further research problems.
Megatrends and Trends Shaping Supply Chain Innovation
Authors: Kalaitzi Dimitra , Matopoulos Aristides , Fornasiero Rosanna , Sardesai Saskia , Barros Ana Cristina , Balech Sébastien , Muerza Victoria
Published: December 2020

Companies operate in a macro-environment that is changing considerably due to large, transformative global forces namely megatrends and trends. The wave of these megatrends and trends generates new prospects as well as challenges for the future of supply chains. This chapter provides a review of 23 major megatrends and 72 trends identified in multiple dimensions along Political, Economic, Social, Technological, Legal, and Environmental (PESTLE) dimensions. The results are based on a systematic literature review and an experts’ workshop, and can be used to generate future supply chain scenarios.
Unveiling the Challenges of Future Supply Chains: An Explorative Analysis
Authors: Gürbüz Mustafa Çağrı , Muerza Victoria , Marchiori Irene , Zangiacomi Andrea
Published: December 2020

This chapter focuses on the identification of challenges that supply chains of the future will most likely face. The primary input in this process are the potential optimistic/pessimistic/intermediate future scenarios based on trends within political, economic, social, technological, legal, and environmental dimensions. Based on such input, we present a list of major challenges/opportunities in relation to the design and operations of Supply Chains (SCs) in the near future. The preliminary list is calibrated and validated based on the input from industry stakeholders (to account for the perspectives of different supply chain actors such as buyers, suppliers, policy makers, and supply chain facilitators) in order to make sure that these challenges are indeed of practical relevance and grounded in reality. The aforementioned challenges are aggregated into several clusters aiming at providing decision makers with a tool that would enable them to quickly and easily spot the relevant challenges and take proper actions to mitigate any potential risk.
Mapping Enabling Technologies for Supply Chains with Future Scenarios
Authors: Senna Pedro Pinho , Stute Markus , Balech Sebastien , Zangiacomi Andrea
Published: December 2020

Driven by the current digital transformation, European companies rely on accurate forecasting of future trends and prediction of most useful technologies in order to maintain their competitive edge. For this purpose, the mapping of enabling technologies to future scenarios becomes a valuable tool for practitioners and researchers alike, especially when considering the disruptive events that surround SCs design, implementation and management. This research sets forth to fill this gap by presenting a technology mapping of enabling technologies based on technology portfolio approach, expert elicitation and literature. The final outcome is the mapping of the enabling technologies to the characteristics of the future European SC scenarios.
Paths to Innovation in Supply Chains: The Landscape of Future Research
Authors: Fornasiero Rosanna , Marchiori Irene , Pessot Elena , Zangiacomi Andrea , Sardesai Saskia , Barros Ana Cristina , Thanous Eva , Weerdmeester Ron , Muerza Victoria
Published: December 2020

This chapter presents a Strategic Research and Innovation Agenda for supply chain and it is the result of an intensive work jointly performed involving a wide network of stakeholders from discrete manufacturing, process industry and logistics sector to put forward a vision to strengthen European Supply Chains for the next decade. The work is based on matching visions from literature and from experts with several iterations between desk research and workshops, focus groups and interviews. The result is a detailed analysis of the supply chain strategies identified as most relevant for the next years and definition of the related research and innovation topics as future developments and steps for the full implementation of the strategies, thus proposing innovative and cutting-edge actions to be implemented based on technological development and organisational change.
Welcome to the World Class University: Introduction
Authors: Rider Sharon , Peters Michael A. , Hyvönen Mats , Besley Tina
Published: December 2020

The notion of World Class Universities, and the use of rankings in general, has been an object of study for decades. Perhaps the first major critical work was Ellen Hazelkorn’s Rankings and the reshaping of higher education: The battle for world-class excellence (2011). Just as the influence of rankings shows no sign of abating, neither does the impetus to provide practical proposals for how to use them to advantage, or, alternatively, to examine the sources and effects of the practices involved. Recent interventions belonging to the first category are Downing and Ganotice’s World university rankings and the future of higher education (2017), while Stack’s Global university rankings and the mediatization of higher education (2016) and Hazelkorn’s Global rankings and the geopolitics of higher education: Understanding the influence and impact of rankingson higher education, policyand society (2016) are notable examples of the latter. The essays presented in the present volume are intended to contribute to our understanding of the phenomenon, its causes and consequences by filling three functions: (i) to provide an updated analysis of current trends in rankings and an examination of recent data regarding World Class University (WCU) initiatives relevant to the form and content of higher education; (ii) to study these especially with an eye to particular ramifications for work on the shop floor, that is to say, for university teachers and students; (iii) to investigate possible future courses and alternative trajectories.
World Class Universities, Rankings and the Global Space of International Students
Authors: Börjesson Mikael , Lillo Cea Pablo
Published: December 2020

The notion of World Class University suggests that this category of universities operates at a global and not national level. The rankings that have made this notion recognised are global in their scope, ranking universities on a worldwide scale and feed an audience from north to south, east to west. The very idea of ranking universities on such a scale, it is argued here, must be understood in relation to the increasing internationalisation and marketisation of higher education and the creation of a global market for higher education. More precisely, this contribution links the rankings of world class universities to the global space of international student flows. This space has three distinctive poles, a Pacific pole (with the US as the main country of destination and Asian countries as the most important suppliers of students), a Central European one (European countries of origin and destination) and a French/Iberian one (France and Spain as countries of destination with former colonies in Latin America and Africa as countries of origin). The three poles correspond to three different logics of recruitment: a market logic, a proximity logic and a colonial logic. It is argued that the Pacific/Market pole is the dominating pole in the space due to the high concentration of resources of different sorts, including economic, political, educational, scientific and not least, linguistic assets. This dominance is further enhanced by the international ranking. US universities dominate these to a degree that World Class Universities has become synonymous with the American research university. However, the competition has sharpened. And national actors such as China and India are investing heavily to challenge the American dominance. Also France and Germany, who are the dominant players at the dominated poles in the space, have launched initiative to ameliorate their position. In addition, we also witness a growing critique of the global rankings. One of the stakes is the value of national systems of higher education and the very definition of higher education.
The Marketingisation of Higher Education
Authors: Gibbs Paul
Published: December 2020

This chapter does not stress the marketisation of higher education rather focuses upon the way in which this is done; the marketingisation of higher education. I do not deny that widening access to skills that can fuel growth is a logical extension of a consumerist ideology. What follows acknowledges these structural changes and then focuses on how marketing is a consequence and reinforce of such structural change. Indeed there is a substantial literature which addresses it (e.g. Molesworth et al. Having, being and higher education: The marketization of the university and the transformation of the student into consumer. Teaching in Higher Education, 14(3), 277–287, 2009; Brown R, Carasso H, Everything for sale? The marketisation of UK higher education. Routledge, London, 2013). Nor does it support that marketingation has brought no or only limited contributions to higher education. The expansion of the privileges of higher education to the many from the few, the greater governance and transparency of the process and practices of higher education institutions in their compact with society and a clearer ways to evaluate these activities have, to varying degrees, enhanced higher education. These interventions have opened the market for world class universities (WCUs) allowing them global as well as local reach. Yet it is strange that these improvements are consequences of market interventions by Governments, by publishers in terms of league tables, and by employers in terms of preferred (mythical?) skill sets and not for educative purposes. The emergent practices encouraged by these interventions increase the influence of marketing and facilitate a metamorphosis of institutions from educational entities to market responsive service providers whose intent focuses on impact and enhanced return on capital. This leads WCUs into the endless and Sisyphusan striving, often devoid of any ultimate worthy end but ends which are an inevitable consequence of managing rapidly increasing competition and shifting demands effectively rather than educative priorities. The chapter describes and discusses the consequences.
On Realizing the World-Class University: Litigation and the State
Authors: Novak Judit
Published: December 2020

This chapter examines Dickinson v. Mälardalen University as an empirical manifestation of state action for creating and maintaining world-class universities (WCUs). It advances the argument that while litigation has long been assumed to play a far more limited role in higher education (HE) than it does in other areas of public policy, this element of governing fuels a different form of state building, in which courts and judges—sometimes from even the mere existence or threat of their intervention—can play a crucial role in WCU development. At the same time, we need to ask a variety of questions about the outcomes of lawsuits and their effects on HE. Does litigation have the effect of realizing the WCU, or does it not matter at all whether policy goals are pressed in courts or through legislation and professional choices? If it does matter, how and why? This chapter argues that a turn to the courts and a reliance on more formal, less malleable rules is not merely an alternative route to the same goal; litigation matters because law is different, because judicial decision-making shapes and constrains HE politics and policy in important ways.
World Class at All Costs
Authors: Hyvönen Mats
Published: December 2020

This chapter takes up the now infamous case of the so-called Macchariani Scandal in light of the Karolinska Institute’s tactics for maintaining and enhancing its position as a WCU. It pays special attention to research funding policies in general, and, in particular, the role of the chairman of the Institute’s Board of Trustees, the Liberal politician Lars Leijonborg, as an example of how the dream of becoming a world-class country in the increasingly fierce global competition can have far-reaching negative consequences for national higher education systems as well as for individuals.
The contribution of multifocal visual evoked potentials in patients with optic neuritis and multiple sclerosis: a review
Authors: Zafeiropoulos Paraskevas , Katsanos Andreas , Kitsos George , Stefaniotou Maria , Asproudis Ioannis
Published: December 2020

Purpose

To review the evidence on the usefulness of the multifocal visual evoked potential (mfVEP) test in patients with optic neuritis (ON) and/or multiple sclerosis (MS).

Methods

We critically review key published evidence on the use of mfVEP in ON/MS patients and its association with other functional and structural tests.

Results

Multifocal VEP tests are useful in detecting abnormality in patients with ON/MS and monitor the progression of lesions (remyelination, atrophy). In addition, mfVEP has good correlation with conventional visual evoked potential (VEP), standard automated perimetry, optical coherence tomography and magnetic resonance imaging. In patients with ON, mfVEP might be useful in predicting the risk of conversion to MS.
Remaking Political Institutions: Climate Change and Beyond
Authors: Patterson James J.
Published: December 2020

Institutions are failing in many areas of contemporary politics, not least of which concerns climate change. However, remedying such problems is not straightforward. Pursuing institutional improvement is an intensely political process, playing out over extended timeframes, and intricately tied to existing setups. Such activities are open-ended, and outcomes are often provisional and indeterminate. The question of institutional improvement, therefore, centers on understanding how institutions are (re)made within complex settings. This Element develops an original analytical foundation for studying institutional remaking and its political dynamics. It explains how institutional remaking can be observed and provides a typology comprising five areas of institutional production involved in institutional remaking (Novelty, Uptake, Dismantling, Stability, Interplay). This opens up a new research agenda on the politics of responding to institutional breakdown, and brings sustainability scholarship into closer dialogue with scholarship on processes of institutional change and development. Also available as Open Access on Cambridge Core.
Intra‐Valve Elemental Distributions in Arctic Marine Ostracodes: Implications for Mg/Ca and Sr/Ca Paleothermometry
Authors: Rodriguez Maximiliano , Doherty John M. , Man Ho Lai Hilary , Wang Rujian , Xiao Wenshen , Zhou Baochun , Thibodeau Benoit , Not Christelle
Published: December 2020

Reconstructing intermediate and bottom‐water temperature in the Arctic Ocean is key for understanding paleoclimatic phenomena, such as the region's interactions with warm Atlantic waters, stratification, and sea‐ice dynamics. However, benthic proxy archives are sparse throughout the Arctic circle compared to lower latitudes. Trace‐element ratios (E/Ca) derived from ostracodes, a group of bivalved microscopic crustaceans, have shown promise in this regard. Samples for E/Ca measurements typically require rigorous cleaning prior to analysis, and signs of contamination are routinely monitored through the presence of other trace elements such as Al, Fe, and Mn, which are associated with suspected sources of overprinting. However, there has not yet been an intra‐valve investigation of all of these trace elements, which may hinder our ability to effectively identify geochemical overprinting. Here, we present several elemental concentration and E/Ca ratio measurements in two ostracode genera, Krithe and Polycope, extracted from Chukchi Sea sediment samples. We further investigate the intra‐valve distribution of elements within single shells of adult and juvenile specimens using electron probe microanalysis (EPMA). Our findings suggest that brushing and bleach treatments may not be effective for completely eliminating clays from the edges of valves, which can bias paleoclimatologically relevant trace‐element proxies such as Mg/Ca ratios, particularly in the case of incomplete or small samples with low amounts of calcite material. In addition, we report the first trace‐element data from the genus Polycope, which shows potential as a new Arctic paleotemperature archive.
Mainshock and Aftershock Sequence Simulation in Geometrically Complex Fault Zones
Authors: Ozawa So , Ando Ryosuke
Published: December 2020

Aftershocks seem to be located along the trace of the mainshock fault; however, due to the location error, we do not know their exact location relative to the mainshock fault. Here, we hypothesize that most aftershocks occur on small subsidiary faults instead of the mainshock fault, and they are triggered by the local increase of stress due to the rough geometry of the mainshock fault. To explore this scenario, we perform 2‐D earthquake sequence simulations considering a rough main fault and numerous subsidiary faults that obey the rate and state friction law. We show that many aftershocks occur at the side of the main fault, delineating the main fault trace. We also show that the roughness of the main fault decreases the concentration of aftershocks around the tip of the mainshock fault. Our numerical simulation reproduces the Omori‐Utsu law for the temporal decay of aftershocks and reveals the log‐time expansion of the aftershock zone. The variability of focal mechanisms of aftershocks strongly depends on the friction coefficient. Large aftershocks are limited in the tips of the mainshock fault. This is one of the first earthquake sequence simulations based on the continuum mechanics framework that reproduces realistic spatiotemporal aftershock activities.
Understanding adherence to the recording of ecological momentary assessments in the example of tinnitus monitoring
Authors: Schleicher Miro , Unnikrishnan Vishnu , Neff Patrick , Simoes Jorge , Probst Thomas , Pryss Rüdiger , Schlee Winfried , Spiliopoulou Myra
Published: December 2020

The recording of Ecological Momentary Assessments (EMA) can assist people with chronic diseases in monitoring their health state. However, many users quickly lose interest in their respective EMA platforms. Therefore, we studied the adherence of users of the mHealth app TrackYourTinnitus(TYT). The app is used to record EMA in people with tinnitus. 1292 users, who interacted with the app between April 2014 and February 2017, were analyzed in this work. We defined “adherence” based on the dimensions of interaction duration and interaction continuity. We propose methods that are able to predict the (dis)continuation of interaction with the app and identify user segments that are characterized by similar patterns of adherence. For the prediction task we used the data of the questionnaires MiniTF and TSCHQ, which are filled in when the users enter TYT for the first time. Additionally, time series of the eight items of the daily EMA questionnaire were used. The distribution of user activity pertaining to the adherence dimension of interaction duration revealed a very skewed distribution, with most users giving up after only 1 day of interaction. However, many users returned after interrupting for some time. Some of the MiniTF items indicated that the worries of users might have lead to an increased likelihood of returning back to the app. The MiniTF score itself was not predictive, though. The answers to the TSCHQ items, in turn, pointed to user strata (more than 65 years of age at registration), which tended towards higher interaction continuity. As the registration questionnaires predicted adherence only to a limited extent, it is promising to study the activities of the users in the very first days of interaction more deeply. It turned out in this context that the effects of interaction stimulants like personalized and non-personalized tips, pointers to information sources, and mechanisms used in online treatments for tinnitus (e.g., in iCBT) should be further investigated.
Depressive symptoms in response to COVID-19 and lockdown: a cross-sectional study on the Italian population
Authors: Delmastro Marco , Zamariola Giorgia
Published: December 2020

The COVID-19 pandemic and the lockdown orders adopted to prevent the spread of the disease had a huge impact on a personal, social, and economic level for the world population. In Europe, Italy was one of the frontrunner countries dealing with an emergency that significantly affected people’s lives. Previous research on the psychological impact of the pandemic revealed an increase in anxiety, depression, and feelings of distress; however, these studies were conducted on non-representative samples of the population reached through social media channels, a method that is likely to lead to many forms of statistical and methodological bias. For the first time to our knowledge, we assessed the psychological impact of COVID-19 on 6700 Italian individuals, representative of the Italian population in terms of age, gender, and geographical areas revealing higher scores of depressive symptoms in females, younger adults, people reporting professional uncertainty and lower socio-economic status. A positive correlation was also found for individuals living alone, those who could not leave home for going to work, and people with a case of COVID-19 in the family, whereas the region of residence was not a significant predictor of depressive symptoms. These findings underline the importance of considering the psychological effects of COVID-19 and providing support to individuals seeking mental health care.
Deposition distribution of the new coronavirus (SARS-CoV-2) in the human airways upon exposure to cough-generated droplets and aerosol particles
Authors: Madas Balázs G. , Füri Péter , Farkas Árpád , Nagy Attila , Czitrovszky Aladár , Balásházy Imre , Schay Gusztáv G. , Horváth Alpár
Published: December 2020

The new coronavirus disease 2019 (COVID-19) has been emerged as a rapidly spreading pandemic. The disease is thought to spread mainly from person-to-person through respiratory droplets produced when an infected person coughs, sneezes, or talks. The pathogen of COVID-19 is the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It infects the cells binding to the angiotensin-converting enzyme 2 receptor (ACE2) which is expressed by cells throughout the airways as targets for cellular entry. Although the majority of persons infected with SARS-CoV-2 experience symptoms of mild upper respiratory tract infection, in some people infections of the acinar airways result in severe, potentially fatal pneumonia. However, the induction of COVID-19 pneumonia requires that SARS-CoV-2 reaches the acinar airways. While huge efforts have been made to understand the spread of the disease as well as the pathogenesis following cellular entry, much less attention is paid to how SARS-CoV-2 from the environment reach the receptors of the target cells. The aim of the present study is to characterize the deposition distribution of SARS-CoV-2 in the airways upon exposure to cough-generated droplets and aerosol particles. For this purpose, the Stochastic Lung Deposition Model has been applied. Particle size distribution, breathing parameters supposing normal breathing through the nose, and viral loads were taken from the literature. We found that the probability of direct infection of the acinar airways due to inhalation of particles emitted by a bystander cough is very low. As the number of viruses deposited in the extrathoracic airways is about 7 times higher than in the acinar airways, we concluded that in most cases COVID-19 pneumonia must be preceded by SARS-CoV-2 infection of the upper airways. Our results suggest that without the enhancement of viral load in the upper airways, COVID-19 would be much less dangerous. The period between the onset of initial symptoms and the potential clinical deterioration could provide an opportunity for prevention of pneumonia by blocking or significantly reducing the transport of viruses towards the acinar airways. Therefore, even non-specific treatment forms like disinfection of the throat and nasal and oral mucosa may effectively keep the viral load of the upper airways low enough to avoid or prolong the progression of the disease. In addition, using a tissue or cloth in order to absorb droplets and aerosol particles emitted by own coughs of infected patients before re-inhalation is highly recommended even if they are alone in quarantine.
The transbasal approach to the anterior skull base: surgical outcome of a single-centre case series
Authors: Aftahy A. Kaywan , Barz Melanie , Wagner Arthur , Bermeitinger Julia S. , Delbridge Claire , Negwer Chiara , Meyer Bernhard , Gempt Jens
Published: December 2020

A variety of sinonasal tumours, meningiomas or other lesions of the anterior skull base involve the paranasal sinuses and the periorbital area. The transbasal approach (TBA) has turned out to be a feasible technique to reach those lesions. A retrospective review at a neurosurgical university department between November 2007 and January 2020 with adult patients who underwent resection of oncologic pathologies through TBA. Surgical technique, extent of resection (EOR), clinical outcome and postoperative complications were analysed. 18 TBAs between November 2007 and January 2020 were performed. Median age was 62 (range 25–83), 7 female and 11 male patients. Gross total resection rate was 85.8% throughout all entities. Four (22.2%) patients suffered from WHO°I meningiomas and 14 (77.7%) from other extra-axial lesions. Preoperative Karnofsky Performance Status Scale (KPSS) was 80% (range 40–90), postoperative KPSS 80% (range 20–100). Rate of postoperative complications requiring intervention was 16.7%. Median follow-up was 9.8 (range 1.2–71.8) months. Modifications and extensions of the classic TBA are not mandatory. Complete resection can be performed under functional and cosmetic-preserving aspects. Second-step procedures such as transnasal approaches may be performed to avoid high morbidity of more aggressive TBAs, if necessary. Surgical considerations should be kept simple and straightforward.
A tale of two metal ions: contrasting behaviors of high oxidation states of Cu and Mn in a bicarbonate–H2O2 system
Authors: Yang Zhiwei , Tan Xiaonan , Tang Daojian , Li Jing , Ma Jiahai
Published: December 2020

A tale of two metal ions: Cu-bicarbonate–H2O2 efficiently degrades Congo red dye while the corresponding Mn system does not.
Cobalt single atoms anchored on nitrogen-doped porous carbon as an efficient catalyst for oxidation of silanes
Authors: Yang Fan , Liu Zhihui , Liu Xiaodong , Feng Andong , Zhang Bing , Yang Wang , Li Yongfeng
Published: December 2020

The single atom Co–N–C-800 catalyst exhibits high catalytic activity, good recyclability, and wide applicability to diverse substrate in oxidation of organosilanes.
Rare earth oxynitrides: promising visible-light-driven photocatalysts for water splitting
Authors: Jiang Shijia , Liu Yanxin , Xu Jun
Published: December 2020

Perovskite-type rare earth oxynitrides are promising visible-light-driven photocatalysts for water splitting.
Dual function organic active materials for nonaqueous redox flow batteries
Authors: Attanayake N. Harsha , Liang Zhiming , Wang Yilin , Kaur Aman Preet , Parkin Sean R. , Mobley Justin K. , Ewoldt Randy H. , Landon James , Odom Susan A.
Published: December 2020

X-ray crystal structures of a phenothiazine posolyte and viologen negolyte and cyclic voltammograms of a solution containing both compounds.
Nickel(ii) di-aqua complex containing a water cluster: synthesis, X-ray structure and catecholase activity
Authors: Shit Madhusudan , Maity Suvendu , Bera Sachinath , Mudi Prafullya Kumar , Biswas Bhaskar , Weyhermüller Thomas , Ghosh Prasanta
Published: December 2020

A trans-diaquanickel(ii) complex with a tetradentate aryloxyacetic acid ligand that forms a six membered water cluster in crystals and exhibits catecholase activity with a good turnover number is reported.
K3B4PO10and K2MB4PO10(M = Rb/Cs): rare mixed-coordinated borophosphates with large birefringence
Authors: Hou Ying , Zhang Bingbing , Wu Hongping , Yu Hongwei , Hu Zhanggui , Wang Jiyang , Wu Yicheng
Published: December 2020

Mixed-coordinated borophosphates with a large B/P ratio, K3B4PO10and K2MB4PO10(M = Rb/Cs), exhibit deep-UV cut-off edges and a relatively large birefringence.
Ferrocene-based porous organic polymer derived N-doped porous carbon/Fe3C nanocrystal hybrids towards high-efficiency ORR for Zn–air batteries
Authors: Liu Xia , Liang Xiaoming , Lou Han , Wang Huiru , Li Hui , Zhang Shujuan , Zhu Shourong , Han Weina , Zhou Baolong
Published: December 2020

Two novel ferrocenyl POPs with tunable morphology were prepared. Pyrolysis of Fc-Car yields carbon based catalysts with embedded Fe/Fe3C sites, showing high ORR activity in both alkaline and neutral media, which are applicable to Zn–air battery.
Micromachined inertial switch for sub‐g monitoring using gravity‐based threshold compensation
Authors: You Rui , Lu Wenshuai , Ruan Yong , Hao Yilong
Published: December 2020

This letter presents the original design of a microelectromechanical systems inertial switch with ultra‐low threshold (∼0.6 g) and great potential for batch manufacturing. The gravity is utilized to narrow the gap between electrodes during operation, defined here as threshold compensation. This lightens the fabrication burden, enabling the device to be made by standard silicon‐on‐glass micromachining without excessive optimization. Finite element analysis has been conducted to demonstrate positive effects of gravity involvement (9.4 μm reduction of the gap) and compliance design of the movable electrodes (multiplied contact time and less than half coefficient of restitution). Fabricated inertial switches have been installed into a vibration system to test fundamental characteristics. Under vibration conditions with amplitude of 0.6 g and frequencies from 25 to 40 Hz, the devices achieve reliable switching with triggering time ranging from 81.2 to 119.3 μs.
Design of a wideband quasi‐Yagi antenna with filtering response
Authors: Zhu Yanyuan , Wang Min , Wang Jianpeng , Chen Jianxin
Published: December 2020

This letter presents a wideband quasi‐Yagi antenna with high selective filtering responses and good radiation performance. The proposed antenna is formed by a microstrip‐slotline‐microstrip transition structure as the filtering network, a driver dipole, and a parasitic strip element. Attributing to the integrated wideband filtering balun network, a wideband performance in the antenna with stable gain can be achieved. Moreover, two radiation nulls are introduced near both sides of the gain passband by utilizing the source‐load coupling in the filtering network to acquire a sharp skirt selectivity. To verify the design concept, a prototype is fabricated and measured. Results exhibit an impedance bandwidth of 63.5% from 3.0 to 5.79 GHz with a stable gain average of 5 dBi over the whole operation band. Besides, two radiation nulls occur at 2.6 and 6.85 GHz, respectively. The simulated results are in good agreement with the measured counterparts.
Multi‐resonator application on size reduction for retransmission‐based chipless RFID tag
Authors: Hossain A. K. M. Z. , Ibrahimy M. I. , Motakabber S. M. A. , Azam S. M. K. , Islam M. S.
Published: December 2020

Here, a ‘truncated C’‐shaped planar coupled line resonator for UWB retransmission‐based chipless RFID has been presented. The resonator is small compared to other existing resonators in the retransmission‐based chipless RFID family. Two different coded multi‐resonator prototype tags have been designed and validated with newly designed planar microstrip fingertip‐shaped antennas. A good agreement is found between simulation and measurement responses. From the system validation, different coding combinations have been extracted when all resonators are present (111111111) and when three resonators are absent (110110101). It is found that with this resonator, 9 bits can be imposed instead of the existing planar rectangular resonator that gives only 1 bit with a larger size. Hence, as much as 86.7% of the occupied area is reduced by the resonator presented in this work. This work is anticipated to motivate the researchers in developing UWB passive RFID tags with higher bit density and smaller sizes for item tagging and sensing applications.
Hough transform based ego‐velocity estimation in automotive radar system
Authors: Lim Sohee , Lee Seongwook
Published: December 2020

In general, the velocity estimated through the automotive radar is the relative velocity between the ego‐vehicle and the target. To estimate the absolute velocity of the ego‐vehicle (i.e. ego‐velocity), it is necessary to get help from other automotive sensors, such as cameras and lidars. In this letter, therefore, a method for estimating the ego‐velocity is proposed using only radar sensor data. To estimate the ego‐velocity, stationary targets in the detection result have to be identified because the velocity relative to the stationary target can be directly converted to the ego‐velocity. In the proposed method, the radar data is first processed to extract the relative distance from the ego‐vehicle to the target, relative velocity between the ego‐vehicle and the target, and angle between the ego‐vehicle and the target. Then, the detected targets are represented in the angle‐velocity domain because moving and stationary targets in this domain exhibit different characteristics. In other words, the moving targets are randomly placed, but the stationary targets exist around a specific line. Finally, the Hough transformation is applied to automatically determine the line, and the ego‐velocity is calculated from the transform result. The proposed method shows a maximum error of 2.4% in the velocity range of 30–90 km/h.
Will people like your illustration? Popularity assessment of illustrations
Authors: Yang Jiachen , Men Yao , Zhao Yang
Published: December 2020

Illustrations frequently appear in advertisements, films, books, etc. Research into the popularity of illustrations shows practicality and necessity already, which plays an important role in the improvement of illustrations and advertising decisions. In this letter, an Illustration Popularity Assessment Network （IPANet） is designed, inspired by the illustration creation process. Atrous convolutional layers are densely concatenated to extract image composition information and Gram matrix is used to measure the image style. We also introduce a scoring model based on ‘views’ and ‘likes’ to score the popularity of collected illustrations. The IPANet is proved to be effective according to experimental results on the scored illustrations. As far as we know, we are the first to explore the popularity of illustrations and practice successfully.
PotNet: Pothole detection for autonomous vehicle system using convolutional neural network
Authors: Dewangan Deepak Kumar , Sahu Satya Prakash
Published: December 2020

Advancement in vision‐based techniques has enabled the autonomous vehicle system (AVS) to understand the driving scene in depth. The capability of autonomous vehicle system to understand the scene, and detecting the specific object depends on the strong feature representation of such objects. However, pothole objects are difficult to identify due to their non‐uniform structure in challenging, and dynamic road environments. Existing approaches have shown limited performance for the precise detection of potholes. The study on the detection of potholes, and intelligent driving behaviour of autonomous vehicle system is little explored in existing articles. Hence, here, an improved prototype model, which is not only truly capable of detecting the potholes but also shows its intelligent driving behaviour when any pothole is detected, is proposed. The prototype is developed using a convolutional neural network with a vision camera to explore, and validates the potential, and autonomy of its driving behaviour in the prepared road environment. The experimental analysis of the proposed model on various performance measures have obtained accuracy, sensitivity, and F‐measure of 99.02%, 99.03%, and 98.33%, respectively, which are comparable with the available state‐of‐art techniques.
A unipolar thin‐film transistor‐based amplifier with enhanced DC offset suppression
Authors: Xu Yuming , Li Bin , Zhong Wei , Deng Sunbin , Fan Houbo , Wu Zhaohui , Yeung Fion Sze Yan , Kwok Hoi Sing , Chen Rongsheng
Published: December 2020

This letter proposes a unipolar thin‐film transistor (TFT)‐based amplifier design that can provide enhanced DC offset suppression. The amplifier consists of an input AC coupling network and a capacitor bootstrap amplifier. By making the first pole of the input AC‐coupling network coincide with that of the capacitor bootstrap amplifier, a DC offset suppression capability of 40 dB/dec, which is 2× higher than that of the prior arts, can be obtained. An implementation is also proposed and a Rensselaer Polytechnic Institute (RPI) TFT model whose parameters are turned to fit the measured data of our metal‐oxide TFT is used to simulate the circuit. Simulation results show that the implementation has 31 dB midband gain, 0.5 Hz–5 kHz bandwidth, 300 μW power consumptions, and the expected 40 dB/dec DC offset suppression. This design is suitable for applications that need to block large DC interference, such as sensor readout amplifiers.
Multi‐objective manta ray foraging algorithm for efficient operation of hybrid AC/DC power grids with emission minimisation
Authors: Shaheen Abdullah M. , El‐Sehiemy Ragab A. , Elsayed Abdallah M. , Elattar Ehab E.
Published: December 2020

The current paper presents a multi‐objective manta ray foraging algorithm (MO‐MRFA) for efficient operation of hybrid AC and multi‐terminal direct current (MTDC) power grids. The multi‐objective framework aims at achieving economical, technical and environmental benefits by minimising the total production fuel costs, minimising the transmission power losses and minimising the environmental emissions in the AC/MTDC transmission systems. The MRFA imitates three separate independent foraging organisations of the manta rays. It is updated incorporating an additional Pareto archive to preserve the non‐dominated solutions. A dynamic adaptation of the fitness feature is employed by iteratively varying the form of the employed fitness function. Furthermore, a fuzzy decision‐making technique is activated to finally pick the appropriate operating point of the AC/MTDC power grids. The proposed technique is compared with other reported algorithms in the literatures. The applications are conducted on three test systems. These systems are IEEE 30‐bus, IEEE 57‐bus test power systems in addition to real part of the Egyptian grid at West Delta region. Numerical results demonstrate that the proposed MO‐MRFA has great effectiveness and robustness indices over the others. Nevertheless, the proposed MO‐MRFA is successfully extracting several Pareto solutions that meet the techno‐economic requirements with accepted environmental concerns.
Low‐light image enhancement based on Retinex decomposition and adaptive gamma correction
Authors: Yang Jingyu , Xu Yuwei , Yue Huanjing , Jiang Zhongyu , Li Kun
Published: December 2020

Low‐light images suffer from poor visibility and noise. In this paper, a low‐light image enhancement method based on Retinex decomposition is proposed. A pyramid network is first utilized to extract multi‐scale features to improve the quality of Retinex decomposition. Then the decomposed illumination is refined via an adaptive Gamma correction network to handle non‐uniform illumination, while the decomposed reflectance is refined with a lightweight network. Finally, the enhanced image is obtained by element‐wise multiplication between the refined illumination and reflectance components. Quantitative and qualitative experiments demonstrate the superiority of our method over state‐of‐the‐art image enhancement methods.