bluuebunny/crossref_metadata_2025 huggingface dataset:
Cosmology and the massive photon frequency shift in the Standard-Model Extension
Authors: Spallicci Alessandro D. A. M. , Helayël-Neto José A. , López-Corredoira Martín , Capozziello Salvatore
Published: January 2021

The total red shift z might be recast as a combination of the expansion red shift and a static shift due to the energy–momentum tensor non-conservation of a photon propagating through Electro-Magnetic (EM) fields. If massive, the photon may be described by the de Broglie–Proca (dBP) theory which satisfies the Lorentz(-Poincaré) Symmetry (LoSy) but not gauge-invariance. The latter is regained in the Standard-Model Extension (SME), associated with LoSy Violation (LSV) that naturally dresses photons of a mass. The non-conservation stems from the vacuum expectation value of the vector and tensor LSV fields. The final colour (red or blue) and size of the static shift depend on the orientations and strength of the LSV and EM multiple fields encountered along the path of the photon. Turning to cosmology, for a zero $$\Omega _{\Lambda }$$

Ω
Λ

energy density, the discrepancy between luminosity and red shift distances of SNeIa disappears thanks to the recasting of z. Massive photons induce an effective dark energy acting ‘optically’ but not dynamically.
Three regimes of QCD
Authors: Glozman L. Ya.
Published: January 2021

While the QCD Lagrangian as the whole is only chirally symmetric, its electric part has larger chiral-spin [Formula: see text] and [Formula: see text] symmetries. This allows separation of the electric and magnetic interactions in a given reference frame. Artificial truncation of the near-zero modes of the Dirac operator results in the emergence of the [Formula: see text] and [Formula: see text] symmetries in hadron spectrum. This implies that while the confining electric interaction is distributed among all modes of the Dirac operator, the magnetic interaction is located at least predominantly in the near-zero modes. Given this observation one could anticipate that above the pseudocritical temperature, where the near-zero modes of the Dirac operator are suppressed, QCD is [Formula: see text] and [Formula: see text] symmetric, which means absence of deconfinement in this regime. Solution of the [Formula: see text] QCD on the lattice with a chirally symmetric Dirac operator reveals that indeed in the interval [Formula: see text] QCD is approximately [Formula: see text] and [Formula: see text] symmetric which implies that degrees of freedom are chirally symmetric quarks bound by the chromoelectric field into color-singlet objects without the chromomagnetic effects. This regime is referred to as a Stringy Fluid. At larger temperatures this emergent symmetry smoothly disappears and QCD approaches the Quark–Gluon Plasma regime with quasifree quarks. The Hadron Gas, the Stringy Fluid and the Quark–Gluon Plasma differ by symmetries, degrees of freedom and properties.
How Developers Talk About Personal Data and What It Means for User Privacy
Authors: Li Tianshi , Louie Elizabeth , Dabbish Laura , Hong Jason I.
Published: January 2021

While online developer forums are major resources of knowledge for application developers, their roles in promoting better privacy practices remain underexplored. In this paper, we conducted a qualitative analysis of a sample of 207 threads (4772 unique posts) mentioning different forms of personal data from the /r/androiddev forum on Reddit. We started with bottom-up open coding on the sampled posts to develop a typology of discussions about personal data use and conducted follow-up analyses to understand what types of posts elicited in-depth discussions on privacy issues or mentioned risky data practices. Our results show that Android developers rarely discussed privacy concerns when talking about a specific app design or implementation problem, but often had active discussions around privacy when stimulated by certain external events representing new privacy-enhancing restrictions from the Android operating system, app store policies, or privacy laws. Developers often felt these restrictions could cause considerable cost yet fail to generate any compelling benefit for themselves. Given these results, we present a set of suggestions for Android OS and the app store to design more effective methods to enhance privacy, and for developer forums(e.g., /r/androiddev) to encourage more in-depth privacy discussions and nudge developers to think more about privacy.
Daughters of Men
Authors: Rabaan Hawra , Young Alyson L. , Dombrowski Lynn
Published: January 2021

While domestic abuse is an all too common experience for women worldwide, how people experience the abuse and their resources to deal with the abuse differ. In this qualitative, interview-based study, we examine Saudi women's domestic safety concerns living in Saudi Arabia and the United States. Based on non-Western Islamic feminist views of agency, we identify three key practices, focused on how women resist or deal with their domestic violence. For each practice, we highlight how interwoven cultural, religious, and political contexts impact Saudi women's ability to recognize and deal with domestic abuse. We attend to technology's role in enabling or hindering women's agency. These practices include: 1) recognizing abuse, where women identify abusive situations, 2) managing abuse, where women find ways to cope with ongoing or anticipated abuse within their constraints and resources, and 3) seeking non-abusive futures, where women decide how to mitigate the abuse or leave their abuser. Given domestic violence's complicated nature, we highlight several key design recommendations based on women's values.
Pulling Back the Curtain on the Wizards of Oz
Authors: Porcheron Martin , Fischer Joel E. , Reeves Stuart
Published: January 2021

The Wizard of Oz method is an increasingly common practice in HCI and CSCW studies as part of iterative design processes for interactive systems. Instead of designing a fully-fledged system, the 'technical work' of key system components is completed by human operators yet presented to study participants as if computed by a machine. However, little is known about how Wizard of Oz studies are interactionally and collaboratively achieved in situ by researchers and participants. By adopting an ethnomethodological perspective, we analyse our use of the method in studies with a voice-controlled vacuum robot and two researchers present. We present data that reveals how such studies are organised and presented to participants and unpack the coordinated orchestration work that unfolds 'behind the scenes' to complete the study. We examine how the researchers attend to participant requests and technical breakdowns, and discuss the performative, collaborative, and methodological nature of their work. We conclude by offering insights from our application of the approach to others in the HCI and CSCW communities for using the method.
Understanding Women's Remote Collaborative Programming Experiences
Authors: Ying Kimberly Michelle , Rodríguez Fernando J. , Dibble Alexandra Lauren , Boyer Kristy Elizabeth
Published: January 2021

In recent years, remote collaboration has become increasingly common both in the workplace and in the classroom. It is imperative that we understand and support remote collaborative problem solving, particularly understanding the experiences of people from historically marginalized groups whose intellectual contributions are essential for addressing the pressing needs society faces. This paper reports on a study in which 58 introductory computer science students constructed code remotely with a partner following either predefined structured roles (driver and navigator in pair programming) or without predefined structured roles. Between the structured-role and unstructured-role conditions, participants? normalized learning gain, Intrinsic Motivation Inventory scores, and system usability scores were not significantly different. However, regardless of the collaboration condition, women reported significantly higher levels of stress, lower levels of perceived competence, and less perceived choice compared to men. Because computer science is a context in which women have been historically marginalized, we next examined the relationship between student gender and collaborative dialogues by extracting lexical and sentiment features from the textual messages partners exchanged. Results reveal that dialogue features, such as number of utterances, utterance length, and partner sentiment, significantly correlated with women's reports of stress, perceived competence, or perceived choice. These findings provide insight on women's experiences in remote programming, suggest that dialogue features can predict their collaborative experiences, and hold implications for designing systems that help provide collaborative experiences in which everyone can thrive.
CrowdMOT
Authors: Anjum Samreen , Lin Chi , Gurari Danna
Published: January 2021

Crowdsourcing is a valuable approach for tracking objects in videos in a more scalable manner than possible with domain experts. However, existing frameworks do not produce high quality results with non-expert crowdworkers, especially for scenarios where objects split. To address this shortcoming, we introduce a crowdsourcing platform called CrowdMOT, and investigate two micro-task design decisions: (1) whether to decompose the task so that each worker is in charge of annotating all objects in a sub-segment of the video versus annotating a single object across the entire video, and (2) whether to show annotations from previous workers to the next individuals working on the task. We conduct experiments on a diversity of videos which show both familiar objects (aka - people) and unfamiliar objects (aka - cells). Our results highlight strategies for efficiently collecting higher quality annotations than observed when using strategies employed by today's state-of-art crowdsourcing system.
Electrochemical Tip-Enhanced Raman Spectroscopy: An In Situ Nanospectroscopy for Electrochemistry
Authors: Huang Sheng-Chao , Bao Yi-Fan , Wu Si-Si , Huang Teng-Xiang , Sartin Matthew M. , Wang Xiang , Ren Bin
Published: January 2021

Revealing the intrinsic relationships between the structure, properties, and performance of the electrochemical interface is a long-term goal in the electrochemistry and surface science communities because it could facilitate the rational design of electrochemical devices. Achieving this goal requires in situ characterization techniques that provide rich chemical information and high spatial resolution. Electrochemical tip-enhanced Raman spectroscopy (EC-TERS), which provides molecular fingerprint information with nanometer-scale spatial resolution, is a promising technique for achieving this goal. Since the first demonstration of this technique in 2015, EC-TERS has been developed for characterizing various electrochemical processes at the nanoscale and molecular level. Here, we review the development of EC-TERS over the past 5 years. We discuss progress in addressing the technical challenges, including optimizing the EC-TERS setup and solving tip-related issues, and provide experimental guidelines. We also survey the important applications of EC-TERS for probing molecular protonation, molecular adsorption, electrochemical reactions, and photoelectrochemical reactions. Finally, we discuss the opportunities and challenges in the future development of this young technique.
Numerical Simulation and Experiment of the Effects of Blade Angle Deviation on the Hydraulic Characteristics and Pressure Pulsation of an Axial‐Flow Pump
Authors: Shi Lijian , Zhu Jun , Yuan Yao , Tang Fangping , Huang Penglan , Zhang Wenpeng , Liu Haiyu , Zhang Xiaowen
Published: January 2021

Inadequate blade angle adjustment or manufacturing errors will cause inconsistencies in the blade angle of an axial‐flow pump. In this study, the hydrodynamic characteristics of an axial‐flow pump with inconsistent blade angle are investigated by analyzing hydraulic performance and pressure pulsation. The analysis is conducted by performing a numerical simulation combined with a model test. Results show that, relative to the case without blade angle deviation, the case with blade angle deviation exhibits changes in the periodicity of the flow field in the impeller. Such changes result in uneven pressure changes in the impeller passage. The pressure pulsation induced by the blade angle deviation is mainly low‐frequency pulsation; that is, it is twice the rotation frequency. The amplitude of the main frequency pulsation is 1.5–3 times that of the blade without angle deviation. This low frequency that dominates the whole pump device easily causes the vibration and weakens the safety and stability of the pump. The blade angle deviation exerts great influence on the unsteady characteristics. Hence, blade angle deviation seriously affects the safe and stable operation of axial‐flow pumps and pump stations.
Solitons, Breathers, and Lump Solutions to the (2 + 1)‐Dimensional Generalized Calogero–Bogoyavlenskii–Schiff Equation
Authors: Ma Hongcai , Cheng Qiaoxin , Deng Aiping
Published: January 2021

In this paper, a generalized (2 + 1)‐dimensional Calogero–Bogoyavlenskii–Schiff equation is considered. Based on the Hirota bilinear method, three kinds of exact solutions, soliton solution, breather solutions, and lump solutions, are obtained. Breathers can be obtained by choosing suitable parameters on the 2‐soliton solution, and lump solutions are constructed via the long wave limit method. Figures are given out to reveal the dynamic characteristics on the presented solutions. Results obtained in this work may be conducive to understanding the propagation of localized waves.
DSCP: Depthwise Separable Convolution‐Based Passive Indoor Localization Using CSI Fingerprint
Authors: Han Chong , Xun Wenjing , Sun Lijuan , Lin Zhaoxiao , Guo Jian
Published: January 2021

Wi‐Fi‐based indoor localization has received extensive attention in wireless sensing. However, most Wi‐Fi‐based indoor localization systems have complex models and high localization delays, which limit the universality of these localization methods. To solve these problems, a depthwise separable convolution‐based passive indoor localization system (DSCP) is proposed. DSCP is a lightweight fingerprint‐based localization system that includes an offline training phase and an online localization phase. In the offline training phase, the indoor scenario is first divided into different areas to set training locations for collecting CSI. Then, the amplitude differences of these CSI subcarriers are extracted to construct location fingerprints, thereby training the convolutional neural network (CNN). In the online localization phase, CSI data are first collected at the test locations, and then, the location fingerprint is extracted and finally fed to the trained network to obtain the predicted location. The experimental results show that DSCP has a short training time and a low localization delay. DSCP achieves a high localization accuracy, above 97%, and a small median localization distance error of 0.69 m in typical indoor scenarios.
Stimulation of Sigma‐1 Receptor Protects against Cardiac Fibrosis by Alleviating IRE1 Pathway and Autophagy Impairment
Authors: Qu Jing , Li Miaoling , Li Dongxu , Xin Yanguo , Li Junli , Lei Song , Wu Wenchao , Liu Xiaojing
Published: January 2021

Sigma‐1 receptor (Sig1R), a chaperone in the endoplasmic reticulum (ER) membrane, has been implicated in cardiac hypertrophy; however, its role in cardiac fibroblast activation has not been established. This study investigated the possible association between Sig1R and this activation by subjecting mice to sham, transverse aortic constriction (TAC), and TAC plus fluvoxamine (an agonist of Sig1R) treatments. Cardiac function and fibrosis were evaluated four weeks later by echocardiography and histological staining. In an in vitro study, neonatal rat cardiac fibroblasts were treated with fluvoxamine or NE‐100 (an antagonist of Sig1R) in the presence or absence of transforming growth factor beta1 (TGF‐β1). Fibrotic markers, ER stress pathways, and autophagy were then investigated by qPCR, western blotting, immunofluorescence, confocal microscopy, and transmission electron microscopy. Fluvoxamine treatment reduced cardiac fibrosis, preserved cardiac function, and attenuated cardiac fibroblast activation. Inhibition of the IRE1/XBP1 pathway, a branch of ER stress, by a specific inhibitor of IRE1 endonuclease activity, attenuated the pathological process. Fluvoxamine stimulation of Sig1R restored autophagic flux in cardiac fibroblasts, indicating that Sig1R appears to play a protective role in the activation of cardiac fibroblasts by inhibiting the IRE1 pathway and restoring autophagic flux. Sig1R may therefore represent a therapeutic target for cardiac fibrosis.
Three Strategies for Improving Shortest Vector Enumeration Using GPUs
Authors: Esseissah Mohamed S. , Bhery Ashraf , Daoud Sameh S. , Bahig Hatem M.
Published: January 2021

Hard Lattice problems are assumed to be one of the most promising problems for generating cryptosystems that are secure in quantum computing. The shortest vector problem (SVP) is one of the most famous lattice problems. In this paper, we present three improvements on GPU-based parallel algorithms for solving SVP using the classical enumeration and pruned enumeration. There are two improvements for preprocessing: we use a combination of randomization and the Gaussian heuristic to expect a better basis that leads rapidly to a shortest vector and we expect the level on which the exchanging data between CPU and GPU is optimized. In the third improvement, we improve GPU-based implementation by generating some points in GPU rather than in CPU. We used NVIDIA GeForce GPUs of type GTX 1060 6G. We achieved a significant improvement upon Hermans’s improvement. The improvements speed up the pruned enumeration by a factor of almost 2.5 using a single GPU. Additionally, we provided an implementation for multi-GPUs by using two GPUs. The results showed that our algorithm of enumeration is scalable since the speedups achieved using two GPUs are almost faster than Hermans’s improvement by a factor of almost 5. The improvements also provided a high speedup for the classical enumeration. The speedup achieved using our improvements and two GPUs on a challenge of dimension 60 is almost faster by factor 2 than Correia’s parallel implementation using a dual-socket machine with 16 physical cores and simultaneous multithreading technology.
A New Predictive Method for CO2-Oil Minimum Miscibility Pressure
Authors: Ge Dangke , Cheng Haiying , Cai Mingjun , Zhang Yang , Dong Peng
Published: January 2021

Gas injection processes are among the effective methods for enhanced oil recovery. Miscible and/or near miscible gas injection processes are among the most widely used enhanced oil recovery techniques. The successful design and implementation of a miscible gas injection project are dependent upon the accurate determination of minimum miscibility pressure (MMP), the pressure above which the displacement process becomes multiple-contact miscible. This paper presents a method to get the characteristic curve of multiple-contact. The curve can illustrate the character in the miscible and/or near miscible gas injection processes. Based on the curve, we suggest a new model to make an accurate prediction for CO2-oil MMP. Unlike the method of characteristic (MOC) theory and the mixing-cell method, which have to find the key tie lines, our method removes the need to locate the key tie lines that in many cases is hard to find a unique set. Moreover, unlike the traditional correlation, our method considers the influence of multiple-contact. The new model combines the multiple-contact process with the main factors (reservoir temperature, oil composition) affecting CO2-oil MMP. This makes it is more practical than the MOC and mixing-cell method, and more accurate than traditional correlation. The method proposed in this paper is used to predict CO2-oil MMP of 5 samples of crude oil in China. The samples come from different oil fields, and the injected gas is pure CO2. The prediction results show that, compared with the slim-tube experiment method, the prediction error of this method for CO2-oil MMP is within 2%.
Case Reports of a New Method for Differential Diagnosis of Calcified Carotid Artery Atheroma
Authors: de Oliveira Guilherme Augusto Alves , de Sá Cleiterson Rezende , Junior Omar Ribeiro Santos , Santos Rafael Pereira da Mata , Manzi Flávio Ricardo
Published: January 2021

Introduction. Early diagnosis of calcified atheromas may decrease morbidity and mortality caused by brain and cardiovascular diseases, in which atherosclerosis is the main etiological factor of these pathologies. Dental examinations with the aim of detecting this pathology have been in progress since 1981, such as panoramic radiography, considered the most widely studied method for this diagnosis. However, some limitations of this exam have been reported with reference to inability to visualize the cervical region and difficulty of establishing a precise diagnosis because of many structures and calcifications that have similar radiographic characteristics. Case Report. The present study to describe a dental radiographic technique for establishing the differential diagnosis of calcified atheromas regarding other calcifications and reporting 3 clinical cases that demonstrate its effectiveness in different clinical situations. Discussion. Manzi Projection can promote a differential diagnosis of calcified atheromas in dental practice and consequently subsidize the clinician for referring the patient to the physician.
Unsupervised Bitext Mining and Translation via Self-Trained Contextual Embeddings
Authors: Keung Phillip , Salazar Julian , Lu Yichao , Smith Noah A.
Published: January 2021

We describe an unsupervised method to create pseudo-parallel corpora for machine translation (MT) from unaligned text. We use multilingual BERT to create source and target sentence embeddings for nearest-neighbor search and adapt the model via self-training. We validate our technique by extracting parallel sentence pairs on the BUCC 2017 bitext mining task and observe up to a 24.5 point increase (absolute) in F1 scores over previous unsupervised methods. We then improve an XLM-based unsupervised neural MT system pre-trained on Wikipedia by supplementing it with pseudo-parallel text mined from the same corpus, boosting unsupervised translation performance by up to 3.5 BLEU on the WMT’14 French-English and WMT’16 German-English tasks and outperforming the previous state-of-the-art. Finally, we enrich the IWSLT’15 English-Vietnamese corpus with pseudo-parallel Wikipedia sentence pairs, yielding a 1.2 BLEU improvement on the low-resource MT task. We demonstrate that unsupervised bitext mining is an effective way of augmenting MT datasets and complements existing techniques like initializing with pre-trained contextual embeddings.
A Primer in BERTology: What We Know About How BERT Works
Authors: Rogers Anna , Kovaleva Olga , Rumshisky Anna
Published: January 2021

Transformer-based models have pushed state of the art in many areas of NLP, but our understanding of what is behind their success is still limited. This paper is the first survey of over 150 studies of the popular BERT model. We review the current state of knowledge about how BERT works, what kind of information it learns and how it is represented, common modifications to its training objectives and architecture, the overparameterization issue, and approaches to compression. We then outline directions for future research.
From Flanders to Lisbon to the Mughal Empire: Hendrick Uwens and the Mathematical Backstage of a Jesuit Missionary’s Life
Authors: Castel-Branco Nuno
Published: January 2021

Hendrick Uwens (1618-1667) was a Flemish-educated Jesuit who became a missionary to the Mughal Empire. Prior to embarking on his missionary work, he taught mixed mathematics in Lisbon in the early 1640s. Both in Europe and India, Uwens often insisted on portraying himself as a mathematician. Mathematics allowed him to be amongst the first teachers of certain aspects of Galileo’s physics and to promote a mechanical worldview – unusual ideas in early Jesuit circles. He also used mathematics to negotiate his missionary appointments in Asia. This paper analyzes the manuscript writings produced by Uwens throughout his life: the letters he wrote in Flanders to the Superior General requesting to be made a missionary, his Portuguese textbook on mechanics, and his correspondence from India to his Jesuit Superiors in Flanders and Rome.
The Case of Albanian as an Islamic Language between Muslim Literary Tradition and National Culture
Authors: Bria Gianfranco
Published: January 2021

This paper aims to apply Bausani’s notion of “Islamic language” to the case of the Albanian language, analysing the cultural and linguistic evolution of its literature according to the various stages of the nation-building process, which concerned also the creation (re-invention) of a standard alphabet. To do so, this work firstly examines the literary production of Albanian Muslim writers during the Ottoman period and then analyses the gradual literary de-Islamisation that invested Albanian culture from the period of Rilindja (Rebirth) until the cultural revolution of the Communist atheist regime.
Suicide in Homer and the Tale of the Heike
Authors: Yamagata Naoko
Published: January 2021

Comparison of suicides and suicidal wishes in Homer and the Tale of the Heike reveals significant similarities. In both worlds, shame, loyalty, and grief are the main causes of suicidal wishes. However, Heike characters are more prone to suicide, while Homeric characters never actually commit suicide. Heike suicides can be seen to derive from the desire to be with one’s community and loved ones, enhanced by the Buddhist belief in an afterlife. Homeric characters display much stronger attachment to life, based on the belief that there is no existence or fame after death worth dying for.
A new species with pink lamellae of Amanita section Caesareae from China

Authors: MU MAN , HUANG HONG-YAN , ZHANG WEN-HAO , TANG LI-PING
Published: January 2021

Amanita fense is described and illustrated as a new species from China based on morphological and molecular evidence. This fungus is mainly distributed in the eastern, northeastern and southwestern regions of China, such as Anhui, Liaoning, and Yunnan. It is characterized by medium-sized basidiomata, a buff to cacao brown pileus with long-striate pileus margin, pinkish lamellae, and ellipsoid to elongate inamyloid spores. This is the fifth taxon with pink lamellae within Amanita section Caesareae. We provide a comparison with similar species and a key to those taxa that have pink to pinkish gills in this section.
Climate-related morphological changes in Pantocsekiella (Mediophyceae) spanning 0-1.2 Ma in the Lake El’gygytgyn, northeastern Russia including Pantocsekiella elgygytgynensis sp. nov.

Authors: LUETHJE MELINA , SNYDER JEFFREY
Published: January 2021

The distribution of diatom species and their evolutionary histories are largely a result of the complex feedback mechanisms in their environment. Arctic lakes are particularly sensitive to climate changes, and the species within these environments reflect these histories. The diatom genus Pantocsekiella is widespread and notably morphologically diverse. Valves from Pantocsekiella in the Arctic Lake El’gygytgyn spanning the last 1.2 Ma were analyzed using light and scanning electron microscopy to investigate how morphological transitions are related to known regional climate events. Quantitative and qualitative observations yielded a high degree of morphological diversity with multiple morphological shifts often associated with inferred extreme cold events. Principal components analysis (PCA) on quantitative morphological variables demonstrates a gradient in morphological variability through time, with a distinct morphology persisting uninterrupted from ~550-~230 ka warranting the establishment of a new species. Valve size within this interval responds to interglacial-glacial cycles, with the largest initial valves occurring during interglacials suggesting sensitivity to lake conditions related to climate.
Chrysophyllum lancisepalum (Sapotaceae, Chrysophylloideae): a new endemic species from the Brazilian Atlantic forest
Authors: LIMA RENATA GABRIELA VILA NOVA DE , LIMA LILIANE FERREIRA , ZICKEL CARMEN SILVIA
Published: January 2021

Chrysophyllum lancisepalum is here in described and illustrated as a new endemic species from the Atlantic forest in Brazil. Chrysophyllum lancisepalum is morphologically similar to C. januariense and C. sierpense, but distinguished by its chartaceous leaves, short petiole, attenuated leaf apex, rounded to obtuse leaf base, lanceolate sepals, fusiform fruit, and a seed with a basi-ventral seed scar. The new species is restricted to the states of Bahia and Espírito Santo, where it preferably grows in the Mussununga ecosystem, which is characterized by a coastal tableland geomorphology. Considering the vulnerability of C. lancisepalum and its very restricted occupation area, we suggest a preliminary conservation status in the Endangered (EN) category, according to the IUCN criteria.
Mechanism for the Formation of Arc-Shaped Cloud Lines over the Tropical Oceans
Authors: Stephan Claudia Christine
Published: January 2021

Satellite images frequently show mesoscale arc-shaped cloud lines with a spacing of several tens of kilometers. These clouds form in a shallow mixed boundary layer in locations where the near-surface horizontal wind speed exceeds ~7 m s−1. Unlike other mesoscale cloud line phenomena, such as horizontal convective rolls, these cloud lines do not align with the wind direction but form at large oblique angles to the near-surface wind. A particularly distinct event of this pattern developed on 31 January 2020 over the western tropical Atlantic Ocean. Radiosonde soundings are available for this time and location, allowing a detailed analysis. By comparing observations with theoretical predictions that are based on Jeffreys’s drag-instability mechanism, it is shown that drag-instability waves may contribute to the formation of this cloud pattern. The theory is formulated in only two dimensions and predicts that wavelike horizontal wind perturbations of this wavelength can grow, because they modulate the surface friction in a way that reinforces the perturbations. The theoretical horizontal wavelengths of 40–80 km agree with the observations. Streamlines from the ERA5 reanalysis show that the directional change of the near-surface wind is likely to contribute to the arc shape but that a radial propagation of an initial instability is also required to explain the strong curvature. Moreover, ERA5 winds suggest that other known explanations for the formation of cloud lines are unlikely to apply in the case studied here.
Measuring Changes in Snowpack SWE Continuously on a Landscape Scale Using Lake Water Pressure
Authors: Pritchard Hamish D. , Farinotti Daniel , Colwell Steven
Published: January 2021

The seasonal snowpack is a globally important water resource that is notoriously difficult to measure. Existing instruments make measurements of falling or accumulating snow water equivalent (SWE) that are susceptible to bias, and most represent only a point in the landscape. Furthermore, the global array of SWE sensors is too sparse and too poorly distributed adequately to constrain snow in weather and climate models. We present a new approach to monitoring snowpack SWE from time series of lake water pressure. We tested our method in the lowland Finnish Arctic and in an alpine valley and high-mountain cirque in Switzerland and found that we could measure changes in SWE and their uncertainty through snowfalls with little bias and with an uncertainty comparable to or better than that achievable by other instruments. More importantly, our method inherently senses change over the whole lake surface, an area in this study up to 10.95 km2, or 274 million times larger than the nearest pluviometer. This large scale makes our measurements directly comparable to the grid cells of weather and climate models. We find, for example, snowfall biases of up to 100% in operational forecast models AROME-Arctic and COSMO-1. Seasonally frozen lakes are widely distributed at high latitudes and are particularly common in mountain ranges, hence our new method is particularly well suited to the widespread, autonomous monitoring of snow-water resources in remote areas that are largely unmonitored today. This is potentially transformative in reducing uncertainty in regional precipitation and runoff in seasonally cold climates.
Understaffing and registered nurses’ turnover: The moderating role of regular rest breaks
Authors: Wendsche Johannes , Hacker Winfried , Wegge Jürgen
Published: January 2021

Current demographic and occupational changes call for new interventions to promote staff retention, especially in nursing where understaffing promotes turnover by increasing workload and strain. Based on previous research examining recovery at work, we investigated whether well-designed rest breaks can function as a resource that buffers adverse consequences of understaffing in nursing. We used a cross-sectional, multi-method study design and assessed understaffing of registered nurses, their regularity of rest breaks, and their annual turnover behaviour in 80 German geriatric nursing teams. As expected, understaffing positively predicted turnover only in work conditions with irregular rest breaks. Hence, implementing regularly scheduled rest breaks can be considered as an effective intervention for improving retention of nurses even in a situation of understaffing.
Analysis of the effect of percutaneous vertebroplasty in the treatment of thoracolumbar Kümmell’s disease with or without bone cement leakage
Authors: Xiao Ya-Ping , Bei Ming-Jian , Yan Cui-Qing , Chang Jian-Zhong
Published: January 2021

Background

Bone cement leakage is a major complication in the treatment of percutaneous vertebroplasty for Kümmell’s disease, and the focus of close attention during the surgery. The purpose of this article was to investigate the clinical outcomes of Kümmell’s disease treated by percutaneous vertebroplasty with or without bone cement leakage.

Methods

A total of 64 patients with Kümmell’s disease from December 2016 to February 2018 treated by percutaneous vertebroplasty were included in the study. After the treatment, 32 cases were respectively divided into two groups according to X-ray examination of bone cement leakage: leakage group and non-leakage group. Preoperative course, age, sex, bone mineral density, damaged segment, anterior vertebral height, vertebral compression rate, Cobb angle, visual analogue scale and Oswestry dysfunction index were compared between the two groups. After surgery, the amount of bone cement injected, operation time, adjacent vertebral refracture rate, visual analogue scale, Oswestry dysfunction index, the recovery value of vertebral anterior height and the improvement value of Cobb angle were compared between the two groups.

Results

The course, age and Cobb angle of the leakage group were significantly greater than those of the non-leakage group (P< 0.05, respectively). The height of anterior vertebral margin and bone mineral density in the leakage group were significantly lower than those in the non-leakage group (P< 0.05, respectively). The two groups were followed up for at least 24 months. The amount of bone cement injected was significantly greater in the leakage group than in the non-leakage group (P=0.000). Visual analogue scale and Oswestry dysfunction index of the two groups on the second day after surgery and at the last follow-up were significantly lower than these before surgery (P< 0.05, respectively), but there was no significant difference between the two groups. In the leakage group, the recovery value of the anterior edge height of the injured vertebra and the improvement value of the Cobb angle on the second day after surgery and at the last follow-up were significantly improved compared with the non-leakage group (P< 0.05, respectively).

Conclusion

Percutaneous vertebroplasty is an effective and minimally invasive treatment for Kümmell’s disease. The leakage group had longer course, older age, more serious kyphotic deformity, vertebral compression and osteoporosis, and higher amount of bone cement injected than these of the non-leakage group. However, there were not significant differences in the rate of adjacent vertebral refractures, visual analogue scale and Oswestry dysfunction index between the two groups. Therefore, the bone cement leakage does not affect the surgical effect.
Methodological flaws on “manual therapy for the pediatric population: a systematic review” by Prevost et al. (2019)
Authors: Yu Hainan , Shearer Heather , Taylor-Vaisey Anne , Mior Silvano , Verville Leslie , Connell Gaelan , Côté Pierre
Published: January 2021

Prevost et al. published a systematic review evaluating the use of manual therapy for clinical conditions in the pediatric population in 2019. However, several methodological flaws in the conduct of the review limit the internal validity of its conclusions. We caution readers about the validity of the recommendations and suggest that the review not be used to inform the clinical management of pediatric patients.
Development and psychometric testing of a questionnaire to assess Nurse’s perception of risks during enteral nutrition
Authors: Feng Ping , Yang Hui-Li , Xu Lan , Ojo Omorogieva , Lu Xiao-Yan , Zhang Hai-Ying , Wang Xiao-Hua
Published: January 2021

Background

Enteral nutrition (EN) therapy is widely used in clinical practice to provide artificial nutrition to patients, while the incidence of adverse events are relatively highly. In the clinical setting, the occurrence of adverse events is associated with the nurse’s risk perception. Thus, using tool to evaluate nurse’s risk perception of enteral nutrition is necessary.

Methods

The draft questionnaire with 37-items was formed by comprehensive literature reviews and semi-structured in-depth interviews with 11 nurses. Two iterations of expert consultations were used to evaluate the content validity, and 4 items were deleted in this phrase. A 33-items questionnaire was used to survey 352 nurses from five tertiary hospitals in China from May to July 2019 with convenience sampling. Content validity, construct validity and known-groups validity were evaluated by content validity index (CVI), exploratory factor analysis, and the comparisons of the different EN risk perception levels of nurses at different working departments and different educational backgrounds, respectively. Reliability was tested by internal consistency, test-retest reliability, and split-half reliability.

Results

After the exploratory factor analysis, four items were excluded. Finally, the newly developed questionnaire included 29 items explaining 71.356% of the total variance. It consisted of three factors: Risks of operation (15 items); Risks of EN-related adverse events (11 items), and Risks of EN solution selection (3 items). The CVI of the questionnaire was 0.95 and the CVI of items ranged from 0.875–1.0. The results of known-groups validity showed that the nurses with different educational backgrounds had a statistically significant difference of EN risk perception (z = − 3.024, p = 0.002), whereas there was not significantly different between EN risk perception of nurses working in different departments (z = − 1.644, p = 0.100). The Cronbach’s α, test-retest reliability, and split-half reliability of the questionnaire were 0.967, 0.818, and 0.815, respectively.

Conclusions

The newly developed questionnaire for assessing nurse’s EN risk perception showed good reliability and validity. It can be used as a tool for nursing managers to assess Chinese nurses’ EN risk perception ability, so as to help to reduce the occurrence of adverse events during EN implementation.
The political economy of sugar-sweetened beverage taxation in Latin America: lessons from Mexico, Chile and Colombia
Authors: Carriedo Angela , Koon Adam D. , Encarnación Luis Manuel , Lee Kelley , Smith Richard , Walls Helen
Published: January 2021

Background

In Latin America, total sales of sugar-sweetened beverages (SSBs) continue to rise at an alarming rate. Consumption of added sugar is a leading cause of diet-related non-communicable diseases (NCDs). Coalitions of stakeholders have formed in several countries in the region to address this public health challenge including participation of civil society organizations and transnational corporations. Little is currently known about these coalitions – what interests they represent, what goals they pursue and how they operate. Ensuring the primacy of public health goals is a particular governance challenge. This paper comparatively analyses governance challenges involved in the adoption of taxation of sugar-sweetened beverages in Mexico, Chile and Colombia. The three countries have similar political and economic systems, institutional arrangements and regulatory instruments but differing policy outcomes.

Methods

We analysed the political economy of SSB taxation based on a qualitative synthesis of existing empirical evidence. We identify the key stakeholders involved in the policy process, identified their interests, and assess how they influenced adoption and implementation of the tax.

Results

Coalitions for and against the SSB taxation formed the basis of policy debates in all three countries. Intergovernmental support was critical to framing the SSB tax aims, benefits and implementation; and for countries to adopt it. A major constraint to implementation was the strong influence of transnational corporations (TNCs) in the policy process. A lack of transparency during agenda setting was notably enhanced by the powerful presence of TNCs.

Conclusion

NCDs prevention policies need to be supported across government, alongside grassroots organizations, policy champions and civil society groups to enhance their success. However, governance arrangements involving coalitions between public and private sector actors need to recognize power asymmetries among different actors and mitigate their potentially negative consequences. Such arrangements should include clear mechanisms to ensure transparency and accountability of all partners, and prevent undue influence by industry interests associated with unhealthy products.
Endoscopic retrieval of an accidentally ingested bur during a dental procedure: a case report
Authors: Kunaparaju Keerthana , Shetty Karthik , Jathanna Vinod , Nath Kartik , M Roma
Published: January 2021

Background

Accidental ingestion of a dental bur during the dental procedure is a rare, but a potentially serious complication. Early recognition and foreign body retrieval is essential to prevent adverse patient outcomes.

Case presentation

A 76-year old male patient, presented to the department with a chief complaint of sensitivity in his upper right back tooth due to attrition. After assessing the pulp status, root canal therapy was planned for the tooth. During the procedure, it was noticed that the dental bur slipped out of the hand piece and the patient had accidentally ingested it. The patient was conscious and had no trouble while breathing at the time of ingestion of the bur although he had mild cough which lasted for a short duration. The dental procedure was aborted immediately and the patient was taken to the hospital for emergency care. The presence and location of the dental bur was confirmed using chest and abdominal x-rays and it was subsequently retrieved by esophagogastroduodenoscopy (EGD) procedure under general anaesthesia on the same day as a part of the emergency procedure. The analysis of this case reaffirms the importance of the use of physical barriers such as rubber dams and gauze screens as precautionary measures to prevent such incidents from occurring.

Conclusion

Ingestion of instruments are uncertain and hazardous complications to encounter during a dental procedure. The need for physical barrier like rubber dam is mandatory for all dental procedures. However, the dentist should be well trained to handle such medical emergencies and reassure the patient by taking them into confidence. Each incident encountered should be thoroughly documented to supply adequate guidance for treatment aspects. This would fulfil the professional responsibilities of the dentist/ clinician and may help avoid possible legal and ethical issues. This case report emphasizes on the need for the usage of physical barriers during dental procedures in order to avoid medical emergencies.
Prevalence of burnout among intensivists in mainland China: a nationwide cross-sectional survey
Authors: Wang Jing , Hu Bo , Peng Zhiyong , Song Huimin , Cai Shuhan , Rao Xin , Li Lu , Li Jianguo
Published: January 2021

Background

Burnout has gained increasing attention worldwide; however, there is a lack of relevant research in China. This study investigated the prevalence and factors associated with burnout in physicians of the intensive care unit (ICU) in mainland China.

Methods

This cross-sectional multicenter study included critical care physicians from all provinces in mainland China (except Tibet). A self-administered survey questionnaire was conducted. It included three parts: demographic information, lifestyle and work information, and the Maslach Burnout Inventory. The levels of burnout were calculated. The factors independently associated with burnout were analyzed by logistic regression.

Results

Finally, 1813 intensivists participated in the survey. The participation rate was 90.7%. The prevalence of burnout and severe burnout was 82.1% (1489/1813) and 38.8% (704/1813), respectively. According to the logistic regression analysis, “difficulty in making treatment decisions” was independently associated with burnout [OR = 1.365, CI (1.060, 1.757)]. “Higher number of children” [OR = 0.714, CI (0.519, 0.981)] and higher “income satisfaction” [OR = 0.771, CI (0.619, 0.959)] were independent protective factors against severe burnout.

Conclusions

The burnout rate in ICU physicians in China is high. Difficult treatment decisions, the number of children, and income satisfaction are independently associated with burnout rates among ICU physicians in China.

Trial registration: Burnout syndrome of the Chinese personnel working in intensive care units: a survey in China, ChiCTR-EOC-17013044, registered October 19, 2017. http://www.chictr.org.cn/showproj.aspx?proj=22329.
Subcutaneous ticks: a first report in a golden jackal, and their absence in non-canid carnivores
Authors: Mechouk Noureddine , Deak Georgiana , Ionică Angela Monica , Ionescu Dan Traian , Chișamera Gabriel Bogdan , Gherman Călin Mircea , Mihalca Andrei Daniel
Published: January 2021

Background

Ticks are hematophagous arthropods which normally attach to the surface of the host’s skin. Their aberrant presence in the subcutaneous tissue of a few carnivores, predominantly foxes, has been reported. However, there have been no reports of this phenomenon in other carnivores such as mustelids or golden jackals. Our aim was to investigate the host spectrum for this aberrant localization of ticks.

Methods

Between 2015 and 2020, a total of 198 carcasses of 12 species of carnivore were examined by parasitological necropsy. When a subcutaneous tick was found, the nodule was removed, carefully dissected, and stored in ethanol. The morphological identification of the subcutaneous tick was carried out to species level.

Results

A single subcutaneous tick was found in one carcass, that of a golden jackal (Canis aureus). The tick was identified as a female Ixodes ricinus. All the other carcasses were negative for the presence of subcutaneous ticks.

Conclusion

To our knowledge, this is the first report of a subcutaneous tick in a golden jackal. This finding broadens the host spectrum of subcutaneous ticks, and reinforces the idea that, among carnivores, this phenomenon only occurs in canids.

Graphical Abstract