bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wideband dielectric properties of silicon and glass substrates for terahertz integrated circuits and microsystems
Authors: Chudpooti Nonchanutt , Duangrit Nattapong , Burnett Andrew D , Freeman Joshua R , Gill Thomas B , Phongcharoenpanich Chuwong , Imberg Ulrik , Torrungrueng Danai , Akkaraekthalin Prayoot , Robertson Ian D , Somjit Nutapong 
Published: April 2021

Abstract
This paper presents a comprehensive study of the optical and electrical dielectric material properties of six commonly-used silicon and glass substrates at terahertz (THz) frequencies, including refractive index, absorption coefficient, dielectric constant and loss factor. The material characterization techniques used in this paper feature THz time-domain transmission and reflection spectroscopy with the measurement frequencies from 0.5 THz up to a maximum of 6.5 THz. Of the six selected dielectric and semiconductor substrates, two are silicon wafers with resistivities ranging from 0.001 to 0.02 Ω-cm. From the measurement results, loss tangents of the selected silicon wafers range from 0.680 to 5.455 and the dielectric constants are from 1.079 to 17.735. The four other wafers are all glass-based substrates: D263 glass, Borofloat 33 glass, fused silica and Sapphire. From the measurements, it is found that the THz dielectric properties vary considerably between the substrate samples e.g. dielectric constants range from 1.925 to 3.207 while loss tangents are from 0.042 × 10−3 to 0.127. Most of the selected silicon and glass-based substrates are quite useful for many THz applications, e.g., THz integrated circuits (THz ICs), THz microsystem technologies (THz MSTs) and THz system-on-a-chip (THz SoC) and system-on-substrate (SiP).
Microwave breakdown in an overmoded relativistic backward wave oscillator operating at low magnetic field
Authors: Xiao Renzhen , Gui Youyou , Zhang Guangshuai , Shi Yanchao , Wang Huida , Chen Kun 
Published: April 2021

Abstract
Microwave breakdown has always been a huge challenge to the development of high-power microwave (HPM) sources. Some unique breakdown phenomena in a novel and powerful overmoded relativistic backward wave oscillator (RBWO) operating at low magnetic field are demonstrated. Three different breakdown mechanisms are utilized to explain these phenomena through detailed electromagnetic field calculation and particle-in-cell demonstration and effective methods are applied or suggested to mitigate the breakdown. The breakdown in the slow wave structure (SWS) mainly results from bombardment by the main electron beam under the intense radial electric field. Increasing the span between the main electron beam and the SWS or applying a coaxial extraction structure operating at coaxial TM01 mode might decrease the radial electric field and lessen the bombardment. The breakdown in the internal reflector originates with the field-induced emission in the inner ring under the intense axial electric field of the TM01 and TM02 mode and the subsequent electron-triggered emission in the outer ring. Removing the central part or constructing a complex reflector surface can suppress the emission. The breakdown in the slot retained for the Rogowski coil results from low pressure gas discharge initiated by microwave leakage from the RBWO into the diode region. Pasting microwave absorbing material into the coaxial diode region helps to obtain normal beam current waveforms measured by the Rogowski coil.
How different power plant types contribute to electric grid reliability, resilience, and vulnerability: a comparative analytical framework
Authors: Ramirez-Meyers K , Neal Mann W , Deetjen T A , Johnson S C , Rhodes J D , Webber M E 
Published: April 2021

Abstract
This work explores the dependability tradeoffs provided by the most common types of central power plants in the United States. Historically, the electricity sector has lacked consensus on how reliability, resilience, and vulnerability differ and how those metrics change depending on the power plant fleet composition. We propose distinct definitions for these metrics and an analytical framework to evaluate power plant fleet dependability. Using data analysis and literature review, we identify fifteen dependability attributes across which we rank eleven power plant types relative to natural gas combined-cycle (NGCC) plants. We use NGCC as the benchmark because it is common to many locations and is of relatively recent vintage. The framework shows that each power plant type has unique dependability benefits and drawbacks. We provide examples of how researchers may use the framework to evaluate grid dependability qualitatively under different scenarios. We find that assuming all attributes that contribute to grid dependability are equally important and additive, electric grid dependability is best supported when power plant fleets include a mixture of power generation technologies. Then, we discuss scenario characteristics that could alter the prioritization and relationships of attributes. We also find that if current capacity installation trends continue to favor low- and zero-carbon power plants, US power grids may benefit from increased resilience and reduced vulnerability at the cost of decreased reliability. We conclude by recommending methods for adapting the framework and quantifying relationships between attributes in individual scenarios.
Smart concrete: an illustration through a smart concrete chess game of potential applications in construction 4.0
Authors: Amghar Bilal , Mansoutre Sandrine , Colin Johan , Florence Celine , Brito Artur De Morais 
Published: April 2021

Abstract
The global performance of a structure or a system can be improved during the process of its construction or operation or end of life, with multifunction and connected elements. Concrete presents several benefits for being used in this way, in particular with integrated electronic systems. This paper deals with smart concrete through a small size example, a chess game, i.e. board and pawns, to illustrate the potential applications on a larger scale in the field of construction. Different kind of sensors can be used in concrete construction. After comparing the advantages and disadvantages of each, magnetic sensors have been chosen to equip the concrete chessboard, handcrafted in the present work. The concrete used is UHPC (Ultra high performance concrete fiber reinforced or not), a new type of concrete with special properties, for the benefits of its mechanical strength and deformation, self-levelling workability and aesthetic surface rendering. Chess pawns and chess board have been cast with a specific protocol to embed the magnets and the sensor inside the concrete, by taking into account both its flocculation and setting times. Results of the tests show the feasibility to use magnetic sensors in concrete systems and show a good transmission of the magnetic signal through the concrete, which is very promising for further development of new concrete smart systems, that are easy and rentable to implement. The permeability of concrete to magnetic fields, robustness and sensitivity of sensor are the advantages of this application.
Fundamental gene network rewiring at the second order within and across mammalian systems
Authors: Sharma Ruby , Kumar Sajal , Song Mingzhou 
Published: April 2021

AbstractMotivationGenetic or epigenetic events can rewire molecular networks to induce extraordinary phenotypical divergences. Among the many network rewiring approaches, no model-free statistical methods can differentiate gene–gene pattern changes not attributed to marginal changes. This may obscure fundamental rewiring from superficial changes.ResultsHere we introduce a model-free Sharma–Song test to determine if patterns differ in the second order, meaning that the deviation of the joint distribution from the product of marginal distributions is unequal across conditions. We prove an asymptotic chi-squared null distribution for the test statistic. Simulation studies demonstrate its advantage over alternative methods in detecting second-order differential patterns. Applying the test on three independent mammalian developmental transcriptome datasets, we report a lower frequency of co-expression network rewiring between human and mouse for the same tissue group than the frequency of rewiring between tissue groups within the same species. We also find second-order differential patterns between microRNA promoters and genes contrasting cerebellum and liver development in mice. These patterns are enriched in the spliceosome pathway regulating tissue specificity. Complementary to previous mammalian comparative studies mostly driven by first-order effects, our findings contribute an understanding of system-wide second-order gene network rewiring within and across mammalian systems. Second-order differential patterns constitute evidence for fundamentally rewired biological circuitry due to evolution, environment or disease.Availability and implementationThe generic Sharma–Song test is available from the R package ‘DiffXTables’ at https://cran.r-project.org/package=DiffXTables. Other code and data are described in Section 2.Supplementary informationSupplementary data are available at Bioinformatics online.
Axillary evaluation in ductal cancer in situ of the breast: challenging the diagnostic accuracy of clinical practice guidelines
Authors: Karakatsanis Andreas , Charalampoudis Petros , Pistioli Lida , Di Micco Rosa , Foukakis Theodoros , Valachis Antonios ,   the SentiNot Trialists Group, Wärnberg F , Bagge Roger Olofsson , Eriksson Staffan , Nagy Guyla , Mohammed Imad , Sundqvist Marie , Kwong Ava , Stålberg Peter 
Published: April 2021

Abstract

Background
Staging of the axilla is not routine in ductal cancer in situ (DCIS) although invasive cancer is observed in 20–25 per cent of patients at final pathology. Upfront sentinel lymph node dissection (SLND) is advocated in clinical practice guidelines in certain situations. These include expected challenges in subsequent SLN detection and when the risk for invasion is high. Clinical practice guidelines are, however, inconsistent and lead to considerable practice variability.

Methods
Clinical practice guidelines for upfront SLND in DCIS were identified and applied to patients included in the prospective SentiNot study. These patients were evaluated by six independent, blinded raters. Agreement statistics were performed to assess agreement and concordance. Receiver operating characteristic curves were constructed, to assess guideline accuracy in identifying patients with underlying invasion.

Results
Eight guidelines with relevant recommendations were identified. Interobserver agreement varied greatly (kappa: 0.23–0.9) and the interpretation as to whether SLND should be performed ranged from 40–90 per cent and with varying concordance (32–88 per cent). The diagnostic accuracy was low with area under the curve ranging from 0.45 to 0.55. Fifty to 90 per cent of patients with pure DCIS would undergo unnecessary SLNB, whereas 10–50 per cent of patients with invasion were not identified as ‘high risk’. Agreement across guidelines was low (kappa = 0.24), meaning that different patients had a similar risk of being treated inaccurately.

Conclusion
Available guidelines are inaccurate in identifying patients with DCIS who would benefit from upfront SLNB. Guideline refinement with detailed preoperative work-up and novel techniques for SLND identification could address this challenge and avoid overtreatment.
Changes in Seasonal Respiratory Illnesses in the United States During the Coronavirus Disease 2019 (COVID-19) Pandemic
Authors: Rodgers Loren , Sheppard Michael , Smith Amanda , Dietz Stephanie , Jayanthi Praveena , Yuan Yan , Bull Lara , Wotiz Samantha , Schwarze Tessa , Azondekon Roseric , Hartnett Kathleen , Adjemian Jennifer , Kirking Hannah L , Kite-Powell Aaron 
Published: April 2021

Abstract

Background
Respiratory tract infections are common, often seasonal, and caused by multiple pathogens. We assessed whether seasonal respiratory illness patterns changed during the COVID-19 pandemic.

Methods
We categorized emergency department (ED) visits reported to the National Syndromic Surveillance Program according to chief complaints and diagnosis codes, excluding visits with diagnosed SARS-CoV-2 infections. For each week during 1 March 2020 through 26 December 2020 (“pandemic period”), we compared the proportion of ED visits in each respiratory category with the proportion of visits in that category during the corresponding weeks of 2017–2019 (“pre–pandemic period”). We analyzed positivity of respiratory viral tests from 2 independent clinical laboratories.

Results
During March 2020, cough, shortness of breath, and influenza-like illness accounted for twice as many ED visits compared with the pre–pandemic period. During the last 4 months of 2020, all respiratory conditions, except shortness of breath, accounted for a smaller proportion of ED visits than during the pre–pandemic period. Percent positivity for influenza virus, respiratory syncytial virus, human parainfluenza virus, adenoviruses, and human metapneumovirus was lower in 2020 than 2019. Although test volume decreased, percent positivity was higher for rhinovirus/enterovirus during the final weeks of 2020 compared with 2019, with ED visits similar to the pre–pandemic period.

Conclusions
Broad reductions in respiratory test positivity and respiratory ED visits (excluding COVID-19) occurred during 2020. Interventions for mitigating spread of SARS-CoV-2 likely also reduced transmission of other pathogens. Timely surveillance is needed to understand community health threats, particularly when current trends deviate from seasonal norms.
Multimorbidity and the risk of major adverse kidney events: findings from the UK Biobank cohort
Authors: Sullivan Michael K , Jani Bhautesh Dinesh , Lees Jennifer S , Welsh Claire E , McConnachie Alex , Stanley Bethany , Welsh Paul , Nicholl Barbara I , Lyall Donald M , Carrero Juan-Jesus , Nitsch Dorothea , Sattar Naveed , Mair Frances S , Mark Patrick B 
Published: April 2021

Abstract

Background
Multimorbidity [the presence of two or more long-term conditions (LTCs)] is associated with a heightened risk of mortality, but little is known about its relationship with the risk of kidney events.

Methods
Associations between multimorbidity and major adverse kidney events [MAKE: the need for long-term kidney replacement therapy, doubling of serum creatinine, fall of estimated glomerular filtration rate (eGFR) to &lt;15 mL/min/1.73 m2 or 30% decline in eGFR] were studied in 68 505 participants from the UK Biobank cohort. Participants were enrolled in the study between 2006 and 2010. Associations between LTC counts and MAKE were tested using survival analyses accounting for the competing risk of death.

Results
Over a median follow-up period of 12.0 years, 2963 participants had MAKE. There were associations between LTC count categories and the risk of MAKE [one LTC adjusted subhazard ratio (sHR) = 1.29, 95% confidence interval (CI) 1.15–1.45; two LTCs sHR = 1.74 (95% CI 1.55–1.96); and three or more LTCs sHR = 2.41 (95% CI 2.14–2.71)]. This finding was more pronounced when only cardiometabolic LTCs were considered [one LTC sHR = 1.58 (95% CI 1.45–1.73); two LTCs sHR = 3.17 (95% CI 2.80–3.59); and three or more LTCs sHR = 5.24 (95% CI 4.34–6.33)]. Combinations of LTCs associated with MAKE were identified. Diabetes, hypertension and coronary heart disease featured most commonly in high-risk combinations.

Conclusions
Multimorbidity, and in particular cardiometabolic multimorbidity, is a risk factor for MAKE. Future research should study groups of patients who are at high risk of progressive kidney disease based on the number and type of LTCs.
Thermoinducible expression system for producing recombinant proteins in Escherichia coli: advances and insights
Authors: Restrepo-Pineda Sara , O. Pérez Néstor , Valdez-Cruz Norma A , Trujillo-Roldán Mauricio A 
Published: April 2021

ABSTRACT
Recombinant protein (RP) production from Escherichia coli has been extensively studied to find strategies for increasing product yields. The thermoinducible expression system is commonly employed at the industrial level to produce various RPs, which avoids the addition of chemical inducers, thus minimizing contamination risks. Multiple aspects of the molecular origin and biotechnological uses of its regulatory elements (pL/pR promoters and cI857 thermolabile repressor) derived from bacteriophage λ provide knowledge to improve the bioprocesses using this system. Here, we discuss the main aspects of the potential use of the λpL/pR-cI857 thermoinducible system for RP production in E. coli, focusing on the approaches of investigations that have contributed to the advancement of this expression system. Metabolic and physiological changes that occur in the host cells caused by heat stress and RP overproduction are also described. Therefore, the current scenario and the future applications of systems that use heat to induce RP production are discussed to understand the relationship between the activation of the bacterial heat shock response, RP accumulation and its possible aggregation to form inclusion bodies.
Chlamydomonas POLQ is necessary for CRISPR/Cas9-mediated gene targeting
Authors: Sizova Irina , Kelterborn Simon , Verbenko Valeriy , Kateriya Suneel , Hegemann Peter 
Published: April 2021

Abstract
The use of CRISPR/Cas endonucleases has revolutionized gene editing techniques for research on Chlamydomonas reinhardtii. To better utilize the CRISPR/Cas system, it is essential to develop a more comprehensive understanding of the DNA repair pathways involved in genome editing. In this study, we have analyzed contributions from canonical KU80/KU70-dependent nonhomologous end-joining (cNHEJ) and DNA polymerase theta (POLQ)-mediated end joining on SpCas9-mediated untemplated mutagenesis and homology-directed repair (HDR)/gene inactivation in Chlamydomonas. Using CRISPR/SpCas9 technology, we generated DNA repair-defective mutants ku80, ku70, polQ for gene targeting experiments. Our results show that untemplated repair of SpCas9-induced double strand breaks results in mutation spectra consistent with an involvement of both KU80/KU70 and POLQ. In addition, the inactivation of POLQ was found to negatively affect HDR of the inactivated paromomycin-resistant mut-aphVIII gene when donor single-stranded oligos were used. Nevertheless, mut-aphVIII was still repaired by homologous recombination in these mutants. POLQ inactivation suppressed random integration of transgenes co-transformed with the donor ssDNA. KU80 deficiency did not affect these events but instead was surprisingly found to stimulate HDR/gene inactivation. Our data suggest that in Chlamydomonas, POLQ is the main contributor to CRISPR/Cas-induced HDR and random integration of transgenes, whereas KU80/KU70 potentially plays a secondary role. We expect our results will lead to improvement of genome editing in C. reinhardtii and can be used for future development of algal biotechnology.
Age-dependent impairment of disease tolerance is associated with a robust transcriptional response following RNA virus infection in Drosophila
Authors: Sheffield Lakbira , Sciambra Noah , Evans Alysa , Hagedorn Eli , Goltz Casey , Delfeld Megan , Kuhns Haley , Fierst Janna L , Chtarbanova Stanislava 
Published: April 2021

Abstract
Advanced age in humans is associated with greater susceptibility to and higher mortality rates from infections, including infections with some RNA viruses. The underlying innate immune mechanisms, which represent the first line of defense against pathogens, remain incompletely understood. Drosophila melanogaster is able to mount potent and evolutionarily conserved innate immune defenses against a variety of microorganisms including viruses and serves as an excellent model organism for studying host–pathogen interactions. With its relatively short lifespan, Drosophila also is an organism of choice for aging studies. Despite numerous advantages that this model offers, Drosophila has not been used to its full potential to investigate the response of the aged host to viral infection. Here, we show that, in comparison to younger flies, aged Drosophila succumb more rapidly to infection with the RNA-containing Flock House virus due to an age-dependent defect in disease tolerance. Relative to younger individuals, we find that older Drosophila mount transcriptional responses characterized by differential regulation of more genes and genes regulated to a greater extent. We show that loss of disease tolerance to Flock House virus with age associates with a stronger regulation of genes involved in apoptosis, some genes of the Drosophila immune deficiency NF-kB pathway, and genes whose products function in mitochondria and mitochondrial respiration. Our work shows that Drosophila can serve as a model to investigate host–virus interactions during aging and furthermore sets the stage for future analysis of the age-dependent mechanisms that govern survival and control of virus infections at older age.
Mapping of a major QTL controlling plant height using a high-density genetic map and QTL-seq methods based on whole-genome resequencing in Brassica napus
Authors: Dong Zhixue , Alam Muhammad Khorshed , Xie Meili , Yang Li , Liu Jie , Helal M M U , Huang Junyan , Cheng Xiaohui , Liu Yueying , Tong Chaobo , Zhao Chuanji , Liu Shengyi 
Published: April 2021

Abstract
Plant height is a crucial element related to plant architecture that influences the seed yield of oilseed rape (Brassica napus L.). In this study, we isolated a natural B. napus mutant, namely a semi-dwarf mutant (sdw-e), which exhibits a 30% reduction in plant height compared with Zhongshuang 11-HP (ZS11-HP). Quantitative trait locus sequencing (QTL-seq) was conducted using two extreme DNA bulks in F2 populations in Wuchang-2017 derived from ZS11-HP × sdw-e to identify QTLs associated with plant height. The result suggested that two QTL intervals were located on chromosome A10. The F2 population consisting of 200 individuals in Yangluo-2018 derived from ZS11-HP × sdw-e was used to construct a high-density linkage map using whole-genome resequencing. The high-density linkage map harbored 4323 bin markers and covered a total distance of 2026.52 cM with an average marker interval of 0.47 cM. The major QTL for plant height named qPHA10 was identified on linkage group A10 by interval mapping and composite interval mapping methods. The major QTL qPHA10 was highly consistent with the QTL-seq results. And then, we integrated the variation sites and expression levels of genes in the major QTL interval to predict the candidate genes. Thus, the identified QTL and candidate genes could be used in marker-assisted selection for B. napus breeding in the future.