bluuebunny/crossref_metadata_2025 huggingface dataset:
Utilizing the column imprints to accelerate no‐partitioning hash joins in large‐scale edge systems
Authors: Li Yu , Xu Wenjian
Published: August 2020

With the increasing number of edge devices in large‐scale edge systems, more and more data are collected to be processed. In such big data scenarios, there is a resurgence of interest in main‐memory analytic databases because of the large RAM capacity of modern servers and the increasing demand for real‐time analytic platforms. In such databases, join is at the heart of almost every query plan. Join also stays as a time‐consuming operation when the denormalization overhead is too large to be applicable. However, the current implementations of these operations have not fully leveraged the new features (eg, SIMD, multi‐core) provided by the modern hardware. The goal of this article is to design efficient algorithms for joins by judiciously exploiting every bit of RAM and all the available parallelisms in each processing unit. For join operations, hash joins have been studied, improved, and reexamined over decades. In this article, we propose to utilize a secondary index to improve hash joins without the physical partitioning. Specifically, in the build phase, the hash values are scattered evenly into the logical partitions of the hash table; in the probe phase, the secondary index is used as the hints to re‐order the probing sequence, such that the locality of the hash probing is increased. We benchmark the performance of the proposed techniques in our column‐store research prototype. Extensive experiments on the synthetic data and the real data show that our methods offer significant performance improvement over their counterparts.
Preliminary study on discrimination of transgenic cotton seeds using terahertz time‐domain spectroscopy
Authors: Li Bin , Shen Xiaochen
Published: August 2020

Presence of genetically modified (GM) organisms is considered to be controversial by legislation and public. It is very important to develop detection methods for early discriminations. Conventional gene detection methods, including protein detection (PCR, ELISA, and so on) and DNA detection (Southern blot, GC/MS, and so on), have the disadvantages of high costs, time‐consuming, complex operations, and destructive of the samples. Terahertz spectroscopy (THz) is a brand‐new radiation with many unique advantages. Most biological macromolecules have fingerprint characteristics in THz band from the current recognition. In this study, feasibility of identifying the transgenic cotton seeds from nontransgenic counterparts using THz spectroscopy method was investigated. The transgenic cotton seeds‐Lumianyan No.28 and nontransgenic cotton seeds‐Xinluzao No.51 were selected and the sample‐making methods were studied; then the refractive and absorption curves of samples were got and given a detailed discussion; finally, absorption index of transgenic and nontransgenic DNA was observed and discussed. The results showed there were small fluctuations in THz band, and refractive index of transgenic seeds was lower than nontransgenic ones and had obvious turning point at 1.4–2.0 THz region. There were significant peaks in 1.0–1.2 and 1.3–1.5 THz regions for the transgenic cotton seeds. Transgenic DNA had higher absorption index than nontransgenic DNA, and there were 3–4 peaks corresponding to the cotton seed samples in 1.0–1.6 THz region. These results showed cotton seeds samples can provide important bio‐information in THz band, and this study provided a basis for developing potential THz‐based gene detection technologies.
Bitcoin and sentiment
Authors: Jo Hoje , Park Haehean , Shefrin Hersh
Published: August 2020

Baker and Wurgler identify high sentiment betas with small startup firms that have great growth potential. On the surface, cryptocurrencies share important features in common with high sentiment beta stocks. This paper investigates the degree to which, during the period July 18, 2010–February 26, 2018, the return to bitcoin displayed the characteristics of a high sentiment beta stock. Using a sentiment‐dependent factor model, the analysis indicates that in large measure, bitcoin returns resembled returns to high sentiment beta stocks. Additionally, we show that bitcoin's expected returns are low when sentiment measured by Volatility Index is high while expected returns are high when sentiment is low.
Hydroschildvortrieb über dem Grundwasserspiegel in hoch durchlässigen Schottern am Eppenbergtunnel – Unerwartete Probleme und ihre Lösung
Authors: Gilgen Samuel , Weh Markus
Published: August 2020

As part of the four‐track improvement of the Zurich‐Berne line near Aarau, the 3.1 km long Eppenberg Tunnel was bored using a multi‐mode TBM. This involved driving more than 700 m in highly permeable soils, mostly above the groundwater table. The hydroshield drive was confronted with considerable problems. The static yield point of the bentonite slurry repeatedly fell below the critical limit of 10 N/m2, despite its frequent replacement. As a result, large quantities of slurry penetrated into the ground and large quantities had to be replaced. In addition, significant additional grout quantities were repeatedly observed for the filling of the annular gap. A systematic and analytical approach in cooperation with all parties involved made it possible to determine the behaviour of the system. Problems started with highly permeable open‐framework gravel layers, which permitted the slurry to penetrate far into the ground. This resulted in overbreak in the crown and local underpressure of the slurry with respect to the grout around the shield. Consequently, the annular gap grout flowed past the shield tail seal and destroyed the thixotropic properties of the slurry by adding free Ca cations. The slurry became unusable and had to be replaced. An extensive set of measures finally made it possible to solve the problems and safely bring the excavation to breakthrough.
Analysing the role of caprock morphology on history matching of Sleipner CO2 plume using an optimisation method
Authors: Ahmadinia Masoud , Shariatipour Seyed M.
Published: August 2020

Geological carbon storage is a promising solution to reduce the CO2 concentration in the atmosphere to ameliorate the effects of global warming from the greenhouse effect. Among feasible storage options, deep saline aquifers are believed to have the largest storage capacity for the gas collected from industrial processes. The first CO2 storage project at a commercial scale in a saline aquifer is in the Sleipner field of the Utsira storage formation in Norway. The long ongoing storage operation in the Sleipner field has been the subject of several past studies attempting to recreate the observed injected CO2 plume migration behaviour. History matching is a method to adjust the input parameters of the model in a way to minimise the mismatch between the simulated and the actual production data in reservoir engineering and applicable to carbon sequestration. Typical parameters adjusted in history matching are porosity, absolute and relative permeability data. In this study, we used an adjoint‐based optimisation tool and showed the importance of caprock morphology in finding an accurate plume match. Using a set of synthetic models, we initially minimised the mismatch between the observed and simulated CO2 plume outline by modifying the caprock topographical details. After testing the optimisation tool on the synthetic models, we applied the methodology to the Sleipner benchmark 2019 model and improved the plume match by locally adjusting caprock elevation within seismic detection limits. We subsequently improved the match by calibrating porosity, permeability, CO2 density and injection rate together in an experiment in which we calibrated all the parameters, including the caprock morphology, to find a better match. The results showed an improvement of around 8% (compared with the original model) in the plume match resulting from an average absolute elevation change of 3.23 m in the model while keeping the other parameters constant. Calibrating the porosity, permeability, CO2 density and injection rate resulted in a 5% improvement in the match, and once caprock morphology was included in the optimisation process, the match improvement increased by 16%. We changed the caprock elevation within a range lower than the seismic detection limit, and results showed that even a few metres variations in the elevation have significant impacts on the plume migration and trapping mechanism in the Sleipner model. The method presented in this work results in a better match than the original seismic data for the Sleipner model. © 2020 The Authors. Greenhouse Gases: Science and Technology published by Society of Chemical Industry and John Wiley & Sons, Ltd.
The role of sleep disturbances in cognitive function and depressive symptoms among community‐dwelling elderly with sleep complaints
Authors: Ji Xiaowen , Fu Yuanyuan
Published: August 2020

Objective

The relationships between sleep problems, cognitive impairments, and depression have been established in the aging population. However, less is known about the role of late‐life onset insomnia and sex involved in these dyad or tripartite relationships. This study aimed to consider onset age of insomnia and sex in the relationship between sleep parameters, cognition and depression among older adults with current insomnia complaints.

Method

A multistep sampling method was adopted to recruit participants with current insomnia complaints in China in 2018. Sleep measures include onset age of insomnia (64 years old or before vs during/after 65), three factors from insomnia severity index (ISI; nighttime, daytime, and perception), excessive daytime sleepiness, and sleep duration. Outcome measures were mini‐mental state examination (MMSE) and center for epidemiologic studies depression scale (CESD).

Results

The average age of older adults was 75 (SD = 7.1). Among them, 62% participants are female. In general, older aged, female, late‐life onset insomnia as well as interaction of sex * onset age of insomnia were significantly associated with poorer cognition. Yet, age, sex, and onset age of insomnia were not significant indicators for depression. For female participants, later onset of insomnia, nighttime symptoms of insomnia, excessive daytime sleepiness and depression were risk factors for cognitive decline. Nevertheless, only daytime sleepiness, together with depression, were found positively associated with male participants' cognitive decline.

Conclusions

There were robust associations between daytime sleepiness, depressive symptoms, and poor cognitive performance. More importantly, late‐life onset insomnia was particularly indicative for poor cognitive performance among female older adults. Future study should emphasize the specific mechanism involved in changes of sleep patterns in the development of cognitive impairment among older adults. Sex differences in the relationship between onset age of insomnia and cognition also require further attention.
Therapeutic plasma exchange for clinically amyopathic dermatomyositis (CADM) associated with rapidly progressive interstitial pneumonia
Authors: Yamagata Akira , Arita Machiko , Tanaka Ayaka , Tokioka Fumiaki , Yoshida Tomohiro , Nishimura Keisuke , Ishida Tadashi
Published: August 2020

Background

Patients with clinically amyopathic dermatomyositis (CADM) with anti‐melanoma differentiation‐associated gene 5 antibody (anti‐MDA5 Ab) frequently develop rapidly progressive interstitial pneumonia (RPIP), often with fatal outcomes. Therapeutic plasma exchange (TPE) has been reported as effective against CADM‐RPIP refractory to conventional immunosuppressive therapy. However, the detailed mechanisms by which TPE improves disease activity of CADM‐RPIP remain unclear.

Aim

To elucidate the clinical and demographic characteristics of patients with anti‐MDA5 Ab‐positive CADM‐RPIP treated with TPE and to analyze changes in laboratory findings before, during, and after TPE.

Materials & Methods

Patients hospitalized for CADM‐RPIP and treated with TPE in 2017 and 2018 were analyzed retrospectively.

Results

Three patients were successfully treated with TPE, with good tolerance. Anti‐MDA5 Ab titers decreased significantly over the course of TPE.

Conclusion

We emphasize that TPE could represent an effective treatment option for CADM‐RPIP refractory to traditional therapy. Removal of anti‐MDA5 Ab and other pathogenic factors may facilitate favorable outcomes.
MicroRNA‐146b correlates with decreased acute respiratory distress syndrome risk, reduced disease severity, and lower 28‐day mortality in sepsis patients
Authors: Chen Wenfeng , Liu Lili , Yang Junhui , Wang Yujun
Published: August 2020

Objective

This study aimed to investigate the predictive value of microRNA‐146b (miR‐146b) on acute respiratory distress syndrome (ARDS) risk, and the correlation of miR‐146b with disease severity and 28‐day mortality in sepsis patients.

Methods

A total of 104 sepsis patients and 100 healthy controls (HCs) were consecutively enrolled, and miR‐146b relative expression in their plasma samples was detected by reverse transcription‐quantitative polymerase chain reaction. In sepsis patients, disease severity was assessed using Acute Physiology and Chronic Health Evaluation II (APACHE II) score and Sequential Organ Failure Assessment (SOFA) score. ARDS occurrence and 28‐day mortality were recorded.

Results

MiR‐146b was decreased in sepsis patients compared to HCs. ARDS occurred in 30 (28.8%) sepsis patients, and miR‐146b was reduced in ARDS sepsis patients compared to non‐ARDS sepsis patients. Meanwhile, miR‐146b distinguished ARDS sepsis patients from non‐ARDS sepsis patients (area under the curve (AUC): 0.728, 95% confidence interval (CI): 0.627‐0.829). Subsequent multivariate logistic regression showed that miR‐146b, age, smoke, respiratory infection, and serum creatinine predicted ARDS risk independently, and their combination well‐discriminated ARDS sepsis patients from non‐ARDS sepsis patients (AUC: 0.863, 95% CI: 0.792‐0.934). Additionally, miR‐146b was negatively correlated with serum creatinine, white blood cell, C‐reactive protein, APACHE II score, and SOFA score, while positively correlated with albumin. Regarding prognosis, miR‐146b was decreased in 28‐day sepsis deaths compared to 28‐day sepsis survivors, and it discriminated 28‐day sepsis deaths from 28‐day sepsis survivors (AUC: 0.785, 95% CI: 0.680‐0.890).

Conclusion

MiR‐146b might serve as a potential biomarker for ARDS prevention and prognostic reflection in sepsis.
A novel prognostic index of hepatocellular carcinoma based on immunogenomic landscape analysis
Authors: Xiao Han , Wang Ben , Xiong Hai‐Xia , Guan Jia‐Fu , Wang Jian , Tan Tao , Lin Kang , Zou Shu‐Bing , Hu Zhi‐Gang , Wang Kai
Published: August 2020

Changes in immune responses to hepatocellular carcinoma (HCC) are closely related to the occurrence, development, and prognosis of this disease. Exploring the role of immune‐related genes (IRGs) in HCC would provide insights into the mechanisms regulating this disease. The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) provide a platform for such research, owing to a large number of HCC samples available for comprehensive and systematic immunogenomics analyses. We analyzed the IRGs expression profile and clinical information of patients with HCC based on the TCGA and ICGC database. Potential molecular mechanisms and properties of the screened IRGs were analyzed across multiple databases. And we analyzed the correlation between IRGs, single‐nucleotide polymorphisms, and copy number variation. A novel prognostic index, based on IRGs, was developed using the LASSO Cox regression algorithm, followed by univariate and multivariate Cox regression analyses to analyze the prognostic index. Information in the ICGC database was used to verify the reliability of the prognostic index. A total of 54 differentially expressed IRGs were found to be significantly associated with HCC prognosis, and there is a significant correlation between their expression level and copy number variation. Functional enrichment analyses indicated that the genes play active roles in tumor and immune‐related signaling pathways. In addition, five potential biomarkers namely IRG, MAPK3, HSP90AA1, HSP90AB1, HSPA4, and CDK4, were identified. Finally, a novel prognostic index, based on IRGs (PSMD14, FABP6, ISG20L2, HGF, BIRC5, IL17D, and STC2), was found useful as an independent prognostic factor, not only for prognosis but also to reflect levels of infiltration in a variety of immune cells. Our team conducted a genomics study of IRGs in HCC and screened several clinically significant IRGs, and our model provides an effective approach for stratification and characterization of patients using IRG‐based immunolabeling tools to monitor the prognosis of HCC.
Microwave assisted synthesis, biological activities, and in silico investigation of some benzimidazole derivatives
Authors: Bhavsar Zeel A. , Acharya Prachi T. , Jethava Divya J. , Patel Dhaval B. , Vasava Mahesh S. , Rajani Dhanji P. , Pithawala Edwin , Patel Hitesh D.
Published: August 2020

Some derivatives of 2‐substituted benzimidazole were prepared via coupling of N‐methyl‐o‐phenylenediamine or o‐phenylenediamine with different aromatic aldehydes catalyzed by Ni(OAc)2 in the presence of chloroform under microwave‐assisted conditions. Structural confirmation of all synthesized molecules was investigated by FT‐IR, 13C NMR, 1H NMR, ESI‐MS, and Elemental analysis. All prepared molecules were examined for in‐vitro pharmaceutical activities like antibacterial, antifungal, antimalarial, antituberculosis, and anti‐oxidant. Additionally, in silico study was also carried out. We also evaluated the steadiness and molecular interaction of docked complex, that is, complex of molecule (7s) with PDB: 5ZNI and complex of derivative (7l) with PDB: 3VLN, we have established a molecular dynamics model on the best dock molecules. All newly prepared molecules were authenticated to have excellent pharmacokinetics stuffs via calculated ADME‐Tox descriptors, which signifying that these derivatives could be utilized as hit for the expansion of the some innovative active compounds.
Design, synthesis and antibacterial activity evaluation of novel 2‐(4‐((1‐aryl‐1H‐1,2,3‐triazol‐4‐yl)methoxy)phenyl)2‐(2‐oxoazetidin‐1‐yl)acetamide derivatives
Authors: Zarei Samaneh , Komeili Golzar , Bahadorikhalili Saeed , Yahya‐Meymandi Azadeh , Karami‐Zarandi Morteza , Larijani Bagher , Biglar Mahmood , Sadat Ebrahimi Seyed Esmaeil , Mahdavi Mohammad
Published: August 2020

In this paper, a novel series of 2‐(4‐((1‐aryl‐1H‐1,2,3‐triazol‐4‐yl)methoxy)phenyl)2‐(2‐oxoazetidin‐1‐yl)acetamide derivatives are synthesized in two steps. The first step involved Ugi multicomponent reaction of β‐alanine, o‐(propargyl)benzaldehyde and isocyanide derivatives. The product of this step, underwent a click 1,3‐dipolar cycloaddition reaction with benzyl azide derivatives. The 2‐(4‐((1‐aryl‐1H‐1,2,3‐triazol‐4‐yl)methoxy)phenyl)2‐(2‐oxoazetidin‐1‐yl)acetamide product was characterized and their antibacterial activities were evaluated against various G‐positive (Staphylococcus aureus and Bacillus subtilis) and G‐negative (Pseudomonas aeruginosa and Escherichia coli) bacteria, using minimal inhibition concentration. The compounds showed very good antimicrobial activity and a number of products have been more active than ciprofloxacin.
Comparative study of sensilla and other tegumentary structures of Myrmeleontidae larvae (Insecta, Neuroptera)
Authors: Acevedo Ramos Fernando , Monserrat Víctor J. , Contreras‐Ramos Atilano , Pérez‐González Sergio
Published: August 2020

Antlion larvae have a complex tegumentary sensorial equipment. The sensilla and other kinds of larval tegumentary structures have been studied in 29 species of 18 genera within family Myrmeleontidae, all of them with certain degree of psammophilous lifestyle. The adaptations for such lifestyle are probably related to the evolutionary success of this lineage within Neuroptera. We identified eight types of sensory structures, six types of sensilla (excluding typical long bristles) and two other specialized tegumentary structures. Both sensilla and other types of structures that have been observed using scanning electron microscopy show similar patterns in terms of occurrence and density in all the studied species (with few exceptions). The sensilla identified are: coeloconica, placoidea, basiconica, trichodea type I, trichodea type II, and campaniformia. All these sensilla have mechano‐ or chemosensorial functions. Some regions of the larval body have been studied using SEM for the first time, such as the surface of the food canal, which bears sensilla coeloconica, and the abdominal segment X, that bears three types of sensilla: coeloconica, basiconica, and campaniformia. Sensilla placodea are newly reported on antlion larvae, being present on the mandibular base, pronotum, mentum, and cardum. Also, new locations of sensilla coeloconica (e.g., on rastra) and sensilla campaniformia (e.g., on odontoid processes) are noted. A novel porous texture with chemoreceptor function has been identified in the base of mandibles. A mechanism of dentate‐notched surfaces that anchor maxillae and mandible, reinforcing the food canal, is detailed. All these sensorial structures, in addition to ocular tubercles for light caption and their great muscular system, confer to these larvae an extraordinary predation capacity to success hunting and living in such harsh environments.
Do all geckos hatch in the same way? Histological and 3D studies of egg tooth morphogenesis in the geckos Eublepharis macularius Blyth 1854 and Lepidodactylus lugubris Duméril & Bibron 1836
Authors: Hermyt Mateusz , Metscher Brian , Rupik Weronika
Published: August 2020

The egg tooth of squamates evolved to facilitate hatching from mineralized eggshells. Squamate reptiles can assist their hatching with a single unpaired egg tooth (unidentates) or double egg teeth (geckos and dibamids). Egg tooth ontogeny in two gekkotan species, the leopard gecko Eublepharis macularius and the mourning gecko Lepidodactylus lugubris, was compared using microtomography, scanning electron microscopy, and light microscopy. Investigated species are characterized by different hardnesses of their eggshells. Leopard geckos eggs have a relatively soft and flexible parchment (leathery) shell, while eggshells of mourning geckos are hard and rigid. Embryos of both species, like other Gekkota, have double egg teeth, but the morphology of these structures differs between the investigated species. These differences in shape, localization, and spatial orientation were present from the earliest stages of embryonic development. In mourning gecko, anlagen of differentiating egg teeth change their position on the palate during embryonic development. Initially they are separated by condensed mesenchyme, but later in development, their enamel organs are connected. In leopard geckos, the localization of egg tooth germs does not change, but their spatial orientation does. Egg teeth of this species shift from inward to outward orientation. This is likely related to differences in structure and mechanical properties of eggshells in the studied species. In investigated species, two hatching mechanisms are possible during emergence of young individuals. We speculate that mourning geckos break the eggshell through puncturing action with egg teeth, similar to the pipping phase of chick and turtles embryos. Egg teeth of leopard geckos cut egg membranes similarly to most squamates. Our results also revealed differences in egg tooth implantation between Gekkota and Unidentata: gekkotan egg teeth are subthecodont (in shallow sockets), while those in unidentates are acrodont (attached to the top of the alveolar ridge). © 2020 Wiley Periodicals LLC
Morphologic analysis of the subtalar joint using statistical shape modeling
Authors: Krähenbühl Nicola , Lenz Amy L. , Lisonbee Rich J. , Peterson Andrew C. , Atkins Penny R. , Hintermann Beat , Saltzman Charles L. , Anderson Andrew E. , Barg Alexej
Published: August 2020

Weightbearing computed tomography (WBCT) enables visualization of the foot and ankle as patients stand under load. Clinical measurements of WBCT images are generally limited to two‐dimensions, which reduces the ability to quantify complex morphology of individual osseous structures as well as the alignment between two or more bones. The shape and orientation of the healthy/normal subtalar joint, in particular, is not well‐understood, which makes it very difficult to diagnose subtalar pathoanatomy. Herein, we employed statistical shape modeling to evaluate three‐dimensional (3D) shape variation, coverage, space, and congruency of the subtalar joint using WBCT data of 27 asymptomatic healthy individuals. The four most relevant findings were: (A) talar and calcaneal anatomical differences were found regarding the presence of (a) the talar posterior process, (b) calcaneal pitch, and (c) curvature of the calcaneal posterior facet; (B) the talar posterior facet articular surface area was significantly greater than the calcaneal posterior facet articular surface area; (C) the posterior facet varied in joint space distance, whereas the anteromedial facet was even; and (D) the posterior and anteromedial facet of the subtalar joint was consistently congruent. Despite considerable shape variation across the population, the posterior and anteromedial articular facets of the subtalar joint were consistently congruent. Results provide a detailed 3D analysis of the subtalar joint under a weightbearing condition in a healthy population which can be used for comparisons to pathological patient populations. The described SSM approach also shows promise for clinical evaluation of the subtalar joint from 3D surface reconstructions of WBCT images.
Antibiotic prophylaxis for prevention of wound infections after soft tissue sarcoma resection: A retrospective cohort study
Authors: Dadras Mehran , Koepp Pascal , Wagner Johannes M. , Wallner Christoph , Sogorski Alexander , Lehnhardt Marcus , Harati Kamran , Behr Björn
Published: August 2020

Background and Objectives

The use of antibiotic prophylaxis for soft tissue sarcoma resection varies widely while little evidence on this topic exists. The aim of this study was to determine the impact of antibiotic prophylaxis on the occurrence of wound infections.

Methods

A single institutional retrospective cohort study was performed on patients who underwent truncal or extremity soft tissue sarcoma resection. The use of antibiotic prophylaxis was assessed and univariate and multivariate analysis of predictors of wound infections was performed.

Results

Nine hundred and fifty‐eight patients could be included. Thirty‐two percent of patients had no antibiotic prophylaxis, 44% of patients received single‐shot prophylaxis, and 24% of patients received single‐shot plus continued antibiotic treatment. Wound infections occurred in 140 patients (15%). Independent risk factors for wound infections upon multivariate analysis were obesity, high American Society of Anesthesiologists (ASA) status, high tumor size and grade, operation time over 120 minutes, and other complications. Antibiotic prophylaxis could not be identified as a protective factor in univariate or multivariate analysis.

Conclusions

A favorable effect of antibiotic prophylaxis on the occurrence of wound infections could not be observed. Although more studies on this subject are needed, our data do not support the general use of antibiotic prophylaxis for soft tissue sarcoma resection.
Plasma‐Induced Polymerizations: A New Synthetic Entry in Liquid Crystal Elastomer Actuators
Authors: Ni Bin , Zhang Mengxue , Guyon Cédric , Keller Patrick , Tatoulian Michael , Li Min‐Hui
Published: August 2020

The research on soft actuators including liquid crystal elastomers (LCEs) becomes more and more appealing at a time when the expansion of artificial systems is blooming. Among the various LCE actuators, the bending deformation is often in the origin of many actuation modes. Here, a new strategy with plasma technology is developed to prepare single‐layer main‐chain LCEs with thermally actuated bending and contraction deformations. Two distinct reactions, plasma polymerization and plasma‐induced photopolymerization, are used to polymerize in one step the nematic monomer mixture aligned by magnetic field. The plasma polymerization forms cross‐linked but disoriented structures at the surface of the LCE film, while the plasma‐induced photopolymerization produces aligned LCE structure in the bulk. The actuation behaviors (bending and/or contraction) of LCE films can be adjusted by plasma power, reaction time, and sample thickness. Soft robots like crawling walker and flower mimic are built by LCE films with bending actuation.
Effects of chloride ions on electrochemical reaction of 316 stainless steel in mixtures of molten nitrate salts
Authors: Zhu M. , Zeng S. , Sharif A. , Cao B. , Zhang H. , Wang M.
Published: August 2020

Effects of chloride ion on decomposition of ternary nitrate and corrosion behaviors of 316 stainless steel (316 SS) were studied by electrochemical corrosion tests in molten salt. Chemical composition and morphology of the corrosion products were analyzed using x‐ray diffraction and scanning electron microscopy equipped with energy disperse spectroscopy. Composition analysis for molten salt combined with morphology analyses of corrosion layer showed that presence of chlorine ions slowed down decomposition of ternary nitrate and increased corrosion rate of stainless steel markedly. The polarization curve obtained indicated that the corrosion current density increased from 3.02 mA ⋅ cm−2 to 8.76 mA ⋅ cm−2 with the addition of 10 % NaCl. Electrochemical impedance spectroscopy indicated a decrease in charge‐transfer resistance of the double layer between 316 SS and ternary Nitrate containing 10 % NaCl, resulting in a decreased corrosion resistance of 316 SS.
Why did I buy this? Purchase regret and repeat purchase intentions: A model and empirical application
Authors: Sarwar Muhammad Arslan , Awang Zainudin , Habib Muhammad Danish , Nasir Jawaria , Hussain Muzzammil
Published: August 2020

This study investigates consumer repurchase behavior and purchases regret in the context of a Steadily Increasing Discount (SID) strategy. A quantitative research approach based on a full‐scaled administrative survey is adopted in the framework of the regret theory. Mall intercept technique is used to collect the cross‐sectional data from respondents. To establish the proposed relational paths, structural equation modeling is applied. The findings of the study suggest that confirmation, price consciousness, and alternative attractiveness have a substantially negative impact on repurchase intention whereas the positive impact on purchase regret is also evident. Furthermore, purchase regret harms repurchase intentions. Moreover, the findings have robust policy implications in the context of corporations offering SID after the economic crisis in developing countries.
sRAGE as severe acute bronchiolitis biomarker, prospective observational study
Authors: Sierra‐Colomina Montserrat , García‐Salido Alberto , Leoz‐Gordillo Inés , Martínez de Azagra‐Garde Amelia , Melen Gustavo , García‐Teresa María Ángeles , Iglesias‐Bouzas Mabel , Nieto‐Moro Montserrat , Ramírez‐Orellana Manuel , Serrano‐González Ana
Published: August 2020

Introduction and Objectives

Acute bronchiolitis (AB) is the leading cause of hospitalization in infants and around 5% require intensive care treatment. Early identification of children diagnosed with AB at a high risk of severe progression is of great interest. The receptor for advanced glycation end products (RAGE), highly expressed in lung tissue, regulates immune responses and inflammation, and its soluble form, sRAGE, is believed to have an anti‐inflammatory role. We hypothesized serum sRAGE might be a major determinant of AB severity and prognosis. This study was conducted to measure serum sRAGE in infants with severe AB and to assess its correlation with clinical severity, immediate complications, and outcome.

Methods

Single‐center, prospective, observational study of hospitalized children with severe bronchiolitis admitted to the Pediatric Intensive Care Unit (PICU), from September 2015 to September 2016.

Results

A total of 52 children and 27 controls were included. The cases age ranged from 11 days to 21 months, resulting in a significant age difference with controls (11.85 vs 4.84 months, P < .01). Serum levels of sRAGE were lower but not significant in severe AB patients than in controls (1350.93 vs 1450.42 pg/mL; P = .399). No correlation was found between serum sRAGE and causative viruses, clinical symptoms, Wood‐Downes score (a clinical severity score) on admission, respiratory support, or length of hospital stay. Serum sRAGE was also lower in the cases having had a previous respiratory disease (1463.84 vs 1072.43 pg/mL; P = .049). However, it was higher in patients with any lung consolidation on the chest X‐ray (1584.79 vs 1131.62 pg/mL; P = .044) and weakly positively correlated with classical biomarkers (maximum C‐reactive protein, +0.295, P = .034; maximum procalcitonin, +0.309; P = .029).

Conclusion

This single‐center study reveals that sRAGE couldn't predict AB severity or outcome in children hospitalized at PICU. Nevertheless, it significantly increased in the presence of any lung consolidation and had a positive correlation with classical biomarkers. The utility of sRAGE in this population could be probably elucidated with a better understanding of AGE‐RAGE axis.
Influence of Deformation on Pb1−xInxTe1−yIy and Pb1−x−ySnxInyTe Films
Authors: Parashchuk Taras , Chernyak Leonid , Nemov Sergey , Dashevsky Zinovi
Published: August 2020

Herein, the original technique for transport measurements at one‐axis deformation is applied for the characterization of In‐doped n‐type Pb1−xSnxTe thin films on a mica substrate. The main advantage of the developed setup is the possibility of obtaining a significantly higher pressure compared with bulk samples. A systematic study of the transport properties as a function of pressure for In‐doped PbTe and PbSnTe films is conducted. A huge deformation of up to ≈6% without sample destruction is obtained within one‐axis deformation and an applied pressure of up to ≈30 kbar for Pb1−xInxTe1−yIy and Pb1−x−ySnxInyTe thin films. This allowed us to determine the position of the In resonance level in the band spectrum of the PbSnTe compound as a function of the pressure. The In impurity level is moving up with the application of pressure. Such a conclusion is confirmed by the Hall effect and electrical conductivity measurements for Pb1−xSnxTe films doped with In and can be explained by the fact that In impurity wave functions are strongly localized and interact weakly with Bloch states of PbSnTe and with each other.
Temperature‐Dependent Local Structural Changes of Amorphous Thin Ge20Te80 Film Revealed by In Situ Resistance, X‐Ray Diffraction, and Raman Spectroscopy Studies
Authors: Sengottaiyan Rathinavelu , Manivannan Anbarasu
Published: August 2020

Although numerous chalcogenide glass systems including GeTe6 and GexSe100−x have been explored for Ovonic Threshold Switch (OTS) selectors in vertically stackable cross‐point memory applications, yet an improved thermal and structural stability at elevated temperatures remains a key challenge. Herein, a systematic temperature‐dependent experimental investigation on the thermal stability and local structural changes of as‐deposited amorphous thin Ge20Te80 film is conducted for a wide range of temperatures from 25 to 260 °C. The coherent experimental studies reveal that the amorphous phase is stable up to 180 °C, and the crystallization process is initiated above 180 °C, by simultaneous crystallization of Te and GeTe until ≈238 °C as substantiated by temperature‐dependent sheet resistance, X‐ray diffraction, and Raman spectroscopic measurements. Furthermore, the local structural changes over the crystallization process of Ge20Te80 thin film are elucidated by Raman spectroscopy. These experimental findings provide a decisive understanding of the thermal stability and structural evolution of Ge20Te80 thin films toward designing stable OTS selector materials.
Asymmetric return–volatility relation around the clock
Authors: Kao Erin H. , Lien Donald , Ho Tsung‐wu
Published: August 2020

This study examines the return‐realized volatility (RV) relation at daily and intraday frequencies. Using daily data, we find the contemporaneous return is the dominating factor for RV, which is in support of the behavioral explanation. For intraday data, we further find a significantly positive (negative) relation between contemporaneous positive (negative) return and RV, which is consistent with prospect theory. Quantile regression analysis documents a U‐shaped (inverted U‐shaped) contemporaneous return‐volatility relation for positive (negative) returns across volatility quantiles during the daytime trading period. In addition, we find the affect heuristic is more aggressive at overnight trading period.
Non‐geostationary satellite orbit communications satellite constellations history
Authors: Butash Tom , Garland Peter , Evans Barry
Published: August 2020

This special issue of the journal on ‘constellations’ comes at a critical time in their development as a second wave of such non‐geostationary satellite orbit (NGSO) systems is being planned and deployed. These mega‐constellations as they have become known are, with a few exceptions, very much larger than those in the first wave and are focused on broadband and 5G applications rather than speech and narrow band data as those deployed in the first wave during the 1990s. However, as we explain in this editorial, there are many similarities in the design and business plans to the first wave and, perhaps, many similar lessons to be learned.
A tutorial on dealing with time‐varying eligibility for treatment: Comparing the risk of major bleeding with direct‐acting oral anticoagulants vs warfarin
Authors: Schnitzer Mireille E. , Platt Robert W. , Durand Madeleine
Published: August 2020

In this tutorial, we focus on the problem of how to define and estimate treatment effects when some patients develop a contraindication and are thus ineligible to receive a treatment of interest during follow‐up. We first describe the concept of positivity, which is the requirement that all subjects in an analysis be eligible for all treatments of interest conditional on their baseline covariates, and the extension of this concept in the longitudinal treatment setting. We demonstrate using simulated datasets and regression analysis that under violations of longitudinal positivity, typical associational estimates between treatment over time and the outcome of interest may be misleading depending on the data‐generating structure. Finally, we explain how one may define “treatment strategies,” such as “treat with medication unless contraindicated,” to overcome the problems linked to time‐varying eligibility. Finally, we show how contrasts between the expected potential outcomes under these strategies may be consistently estimated with inverse probability weighting methods. We provide R code for all the analyses described.
The Heterogenized Hexazatricyclic Complexes as Solid Acid Catalyst for the Degradation of Rhodamine‐b
Authors: Reddy Gontu Ramanjaneya , Kattela Chennakesavulu , Sengottuvelan Balasubramanian
Published: August 2020

The present work describes the one‐pot template synthesis of solid acid photocatalyst, was designed by the copper(II) complex (CPEA) of 14‐membered hexaazamacrocyclic ligand (4, 11‐bis‐ (methyl)‐1, 8 α ‐ methyl benzyl −1, 3, 6, 8, 10, 13‐hexaaza cyclotetradecane) and porous zeolite‐Y. The synthesized homogeneous photocatalyst (CPEA) was impregnated in the micropores of zeolite‐Y and the solid catalyst termed as CPEAY. The CPEA and CPEAY were investigated by XPS, EPR, FTIR, DRS/UV‐visible, XRD, BET, N2 ‐ adsorption isotherms, SEM, TEM, ESI‐mass and TGA. The photocatalytic performance of these compounds evaluated in the removal of rhodamine‐B (RhB) dye under UV and visible light illumination. At optimized parameters, the CPEAY, exhibits 100 % dye removal efficiency for the degradation of RhB, when compared with CPEA complex. The CPEAY catalyst stability and reusability in the degradation of RhB were comprehensively studied for four times and shows the identical catalytic ability with fresh catalyst.
Influence of Cooling and Strain Rates on the Hot Ductility of High Manganese Steels Within the System Fe–Mn–Al–C
Authors: Borrmann Lukas , Senk Dieter , Steenken Bernhard , Rezende Joao Luiz Lopez
Published: August 2020

The ductility curves of high manganese steel grades with a stepwise increasing [Al] content of 0, 1, 3, 5, and 8 wt% for two strain rates (0.01 and 0.001 s−1) and for a varying cooling rate (–3 and −7 Ks−1) have been determined to investigate their influence on the hot ductility behavior. The tests have been conducted at the hot tensile testing unit of the Department of Ferrous Metallurgy of RWTH Aachen University. This equipment is able to perform testing of semisolid samples, e.g., during solidification. After the tensile testing, the specimens are investigated using the scanning electron microscope/energy‐dispersive X‐ray spectroscopy as well as by light optical microscopy to clarify the role of the cooling and strain rates on the hot ductility of high manganese steels and on the formations of precipitates. Furthermore, thermodynamic modeling using the commercial software ThermoCalc is performed. A shifting of the decay of the ductility maximum to lower temperatures down to ≈1273 K for both an increasing strain rate and an increasing cooling rate is determined and this effect is explained through their influences on the microstructure and fracture behavior. Micrograph analyses show that (MnS) precipitates form in contact with early (AlN) precipitates.
Numerical simulation of substandard beam‐column joints with different failure mechanisms
Authors: Yurdakul Özgür , Del Vecchio Ciro , Di Ludovico Marco , Avşar Özgür
Published: August 2020

Generating the nonlinear behavior of substandard beam‐column joints is challenging. Difficulties arise even more in reproducing the contribution of different nonlinear mechanisms (and their mutual effects) on the global cyclic response. This paper deals with the advanced numerical modeling of substandard reinforced concrete (RC) beam‐column joints designed with structural details and material properties non‐conforming to current seismic codes. Refined numerical models developed in VecTor2 and ATENA Science finite element (FE) software are investigated in detail to identify the factors affecting the global and local joint response. Two different modeling strategies are closely compared with experimental results of joint subassemblies with different failure modes in terms of hysteric response, crack pattern and its development, and local deformations at the joint panel and framing members. The advantages‐disadvantages, difficulties in implementing the numerical model and their capability to reproduce the experimental behavior are discussed in detail. The comparison against experimental results in terms of local and global response is useful to assess the accuracy of the proposed models and it provides details on their applicability.
Prediction of early compressive strength of mortars at different curing temperature and relative humidity by a modified maturity method
Authors: Sun Bochao , Noguchi Takafumi , Cai Gaochuang , Chen Qingkai
Published: August 2020

This paper presents an experimental and modeling study on the influence of curing temperature (T) and relative humidity (RH) on the development of early‐age compressive strength of cement mortars. By introducing an RH factor γRH into the age conversion factor of concrete, a modified maturity function was proposed considering both effects of T and RH on the mechanical properties of mortars. Test results proved that T and RH both had a considerable effect on the compressive strength of mortars, especially at the later stage of curing. The RH factor γRH increased as curing RH of mortars, and decreased with their curing age when the mortars were under an unsaturated state. The results also show that the factor γRH could be formulated by a modified hyperbola function. With the proposed RH modified maturity function, the prediction of compressive strength was verified having a high consistency with the experimental results.
Handling the COVID‐19 crisis: Toward an agile model‐based systems approach
Authors: de Weck Olivier , Krob Daniel , Lefei Li , Lui Pao Chuen , Rauzy Antoine , Zhang Xinguo
Published: August 2020

The COVID‐19 pandemic has caught many nations by surprise and has already caused millions of infections and hundreds of thousands of deaths worldwide. It has also exposed a deep crisis in modeling and exposed a lack of systems thinking by focusing mainly on only the short term and thinking of this event as only a health crisis. In this paper, authors from several of the key countries involved in COVID‐19 propose a holistic systems model that views the problem from a perspective of human society including the natural environment, human population, health system, and economic system. We model the crisis theoretically as a feedback control problem with delay, and partial controllability and observability. Using a quantitative model of the human population allows us to test different assumptions such as detection threshold, delay to take action, fraction of the population infected, effectiveness and length of confinement strategies, and impact of earlier lifting of social distancing restrictions. Each conceptual scenario is subject to 1000+ Monte‐Carlo simulations and yields both expected and surprising results. For example, we demonstrate through computational experiments that maintaining strict confinement policies for longer than 60 days may indeed be able to suppress lethality below 1% and yield the best health outcomes, but cause economic damages due to lost work that could turn out to be counterproductive in the long term. We conclude by proposing a hierarchical Computerized, Command, Control, and Communications (C4) information system and enterprise architecture for COVID‐19 with real‐time measurements and control actions taken at each level.
Negative emissions and the long history of carbon removal
Authors: Carton Wim , Asiyanbi Adeniyi , Beck Silke , Buck Holly J. , Lund Jens F.
Published: August 2020

Recent IPCC assessments highlight a key role for large‐scale carbon removal in meeting the objectives of the Paris Agreement. This focus on removal, also referred to as negative emissions, is suggestive of novel opportunities, risks, and challenges in addressing climate change, but tends to build on the narrow techno‐economic framings that characterize integrated assessment modeling. While the discussion on negative emissions bears important parallels to a wider and older literature on carbon sequestration and carbon sinks, this earlier scholarship—particularly from the critical social sciences—is seldom engaged with by the negative emissions research community. In this article, we survey this “long history” of carbon removal and seek to draw out lessons for ongoing research and the emerging public debate on negative emissions. We argue that research and policy on negative emissions should proceed not just from projections of the future, but also from an acknowledgement of past controversies, successes and failures. In particular, our review calls attention to the irreducibly political character of carbon removal imaginaries and accounting practices and urges acknowledgement of past experiences with the implementation of (small‐scale) carbon sequestration projects. Our review in this way highlights the importance of seeing continuity in the carbon removal discussion and calls for more engagement with existing social science scholarship on the subject. Acknowledging continuity and embracing an interdisciplinary research agenda on carbon removal are important aspects in making climate change mitigation research more responsible, and a precondition to avoid repeating past mistakes and failures.

This article is categorized under:

The Carbon Economy and Climate Mitigation > Benefits of Mitigation