bluuebunny/crossref_metadata_2025 huggingface dataset:
Talent recruitment analysis based on Chinese mainland public colleges and universities in perspective of occupation requirement
Authors: Huang Zhengliang , Huang Jin , Zhang Zhentong , Zhu Ming'an , Wei Yan
Published: August 2020

The open recruitment in Chinese mainland public colleges and universities mainly require master's degree or above currently. In the perspective of occupation requirement, combined with recruitment processes, this research analyzed ideological and moral quality, work ethic, ability and quality and others concerned by recruiting units (public colleges and universities), in addition, made moderate comparisons with that of Western countries represented by America. This research aimed to guide worldwide talents who were fond of Chinese culture and wanted to come to China to choose educational positions. It helped personnel administrators in higher education institutions to rethink recruitment processes, so as to improve recruitment efficiency, talent quality, optimize faculty structure and perfect personnel regulations and system. Moreover, it provided clues to an in‐depth exploration and analysis of sino‐american in education, talent management and related policies in universities.
Environmental efficiency in South Asian agriculture: A potential of reducing CO2 emissions and fertilizers usage
Authors: Sharma Sonali
Published: August 2020

South Asian governments have introduced renewable energy policies for the reduction of CO2 emissions while keeping up with the demand for food by enhancing agricultural production. Therefore, it is a need to examine the efficiency analysis of agriculture by incorporating CO2 emissions as a bad output for measuring sustainability in their agriculture practices. Also, the study calculated the potential reduction of CO2 emissions and the usage of fertilizers to make agricultural practices sustainable and environmentally efficient. This study estimated the productivity change, technical, and environmental efficiency of rice production for selected South Asian countries. Data were obtained from the FAO‐STAT website from 2002 to 2014. The change in rice productivity was measured through total factor productivity (TFP) scores by applying the Malmquist Index (MI) approach. Traditional data envelopment analysis (DEA) models and Slacks based model (SBM‐DEA) were applied for the measurement of technical and environmental efficiency, respectively. The results of the MI approach showed that Bangladesh, Bhutan, India, Pakistan, and Sri Lanka were found to have positive changes in TFP. The results of technical and environmental efficiency indicated that Bangladesh, Bhutan, and India were found efficient throughout the study period. Afghanistan and Pakistan were found environmentally most inefficient. The slack obtained from the SBM‐DEA indicated that Pakistan, Afghanistan, and Sri Lanka had a huge potential to reduce CO2 emissions and usage of fertilizers. Furthermore, this study provides an overview of the sustainable status of agriculture and also provides suggestions in selected South Asian countries.
Stereocomplex poly(lactic acid) vascular stents by 3D‐printing with long chain branching structures: Toward desirable crystallization properties and mechanical performance
Authors: Li Jiafeng , Ye Wuyou , Fan Zhongyong , Lu Zhiqian
Published: August 2020

Using pyromelliticdianhydride (PMDA) and polyfunctional epoxy ether (PFE) as branching agent, long chain branching stereocomplex poly(L‐lactide)s and poly(D‐lactide)s was prepared by reactive processing, respectably. Then stereocomplex poly(lactide)s of long chain branching PLLA and PDLA (sc‐PLA/BA) was prepared by solution blending and its fabricated the vascular stents via 3D‐printing.The effects of branching structure on melt crystallization behavior of sc‐PLA/BA investigated by DSC. The influence of the branching agent content on the crystallization ability of samples shows a bell‐shaped relationship, there is a maximum point when the branching agent content is1.5 wt%. When the branching agent content is less than 1.5 wt%, the crystallization ability of the sample increased with the increasing of branching agent content. When the branching agent content exceeded than 1.5 wt%, the crystallization ability of the samples decreased with branching agent content increasing. Such behavior is as the linear PLA branched to dendrite configuration, the enrichment of segments around branching structure within branched chains promoted its nucleation. But the high degree of branching caused inter‐ or intrachians entanglement which obstructed the segments movement and growth into the crystals. The half‐time of crystallization (t1/2) of the samples decreased from 6 minutes for initial sc‐PLA/BA‐0 to 3 minutes of sc‐PLA/BA‐1.5 wt% at 163°C. POM results indicated that nucleation density of sc‐PLA/BA significantly increased with the branching agent increasing. Moreover, mechanical testing demonstrated that forming branching structure could be an effective modification of the mechanical properties for sc‐PLA, its tensile strength and modulus increases from 57.3 MPa and 2.02 GPa to 70.4 MPa and 3.31 GPa, respectively. TGA results analyzed by FWO method and Kissinger method, indicated the apparent activation energy of sc‐PLA/BA samples increases from 96.8 to 113.3 kJ/mol, suggesting the improvement of heat resistance. The CCK‐8 assay, ALP assay and cell Live/Dead assay results indicated that sc‐PLA with branching structure presented very low cell cytotoxicity. Therefore, the long chain branching sc‐PLA matrix with branching agent could effectively improve its crystallization abilities, mechanical properties, heat resistance and biocompatibilities.
c‐Jun acts downstream of PI3K/AKT signaling to mediate the effect of leptin on methionine adenosyltransferase 2B in hepatic stellate cells in vitro and in vivo
Authors: Zhu Xiaofei , Jia Xin , Cheng Fangyun , Tian Haimeng , Zhou Yajun
Published: August 2020

Obese patients, often accompanied by hyperleptinemia, are prone to develop liver fibrosis. A large body of data including the results from human studies suggested the promotion role of leptin, an adipocyte‐derived hormone, in liver fibrosis. Hepatic stellate cell (HSC) activation, a crucial step in liver fibrogenesis, requires global reprogramming of gene expression which is regulated by multiple mechanisms including epigenetic regulation such as methylation of DNA. S‐Adenosylmethionine is a principal biological methyl donor and its biosynthesis is catalyzed by a methionine adenosyltransferase (MAT) such as MATII. MATII consists of the catalytic subunit MAT2A and regulatory subunit MAT2B which are essential for HSC activation. The present research investigated the effect of leptin on the expression of Mat2b in HSCs in vitro and in a leptin‐deficient mouse model. Results demonstrated that leptin significantly increased Mat2b expression. Leptin‐induced Mat2b expression required the PI3K/AKT signaling pathway. c‐Jun, a component of activator protein (AP1), was phosphorylated by leptin‐induced PI3K/AKT signaling and thus potentiated its binding to the element around −964 bp in the Mat2b promoter. MAT2B was involved in leptin‐induced HSC activation and liver fibrosis in a leptin‐deficient mouse model. These results might broaden understanding of the mechanisms underlying the liver fibrogenesis in obese patients with hyperleptinemia. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Fabrication and properties of rigid polyurethane nanocomposite foams with functional isocyanate modified graphene oxide
Authors: Li Ying , Tian Huafeng , Zhang Jing , Zou Wei , Wang Hong , Du Zhongjie , Zhang Chen
Published: August 2020

The modified graphene oxide (GO) with different specific functional groups were prepared and introduced into rigid polyurethane foam (PUF). It was proved that NCO groups were bonded on the surface of GO, which could participate into the polyurethane foaming reaction and dramatically improve the interactions between the filler and matrix. It was found that the cell morphology and the mechanical properties of the PUFs could be effectively improved by adding an appropriate amount of modified GO. The isocyanate‐modified GO could form a stable chemical bond with the matrix, which was more beneficial to improve the mechanical properties. The thermal conductivity slightly increased with the increase of modified GO, however the values were still low enough for thermal insulation applications. Thus, these nanocomposite foams with improved structure and properties would find wide applications in the thermal insulation areas.
Fire behavior of flame retarded sandwich structures containing PET foam cores and epoxy face sheets
Authors: Bethke Christian , Weber Lais , Goedderz Daniela , Standau Tobias , Döring Manfred , Altstädt Volker
Published: August 2020

Within this work, the investigation on interactions of a phosphorus‐containing flame retardant (FR) DEPAl in epoxy face sheets and five different FRs in the PET‐foam core of a sandwich laminate on the fire behavior is focused. Fourteen different combinations of resin face sheets and PET foam cores are produced by vacuum assisted resin infusion (VARI). The combustion behavior of the sandwich laminates is tested by cone calorimetry. The time to ignition is lowered when a FR resin is used while the subsequent burning behavior is mainly influenced by the PET foam core. In order to evaluate the interactions of the flame retardants in the core and face sheet, a total improvement value (TIV) was set up which compares the performance related to the specific FR combinations. The highest TIV value (76%) indicating positive interactions with DEPAl was observed with a 2‐PSMP‐PET core, the lowest value (−2%) with a DEPZn‐PET core.
The comparative performance of wavelet‐based outbreak detector, exponential weighted moving average, and Poisson regression‐based methods in detection of pertussis outbreaks in Iranian infants: A simulation‐based study
Authors: Alimohamadi Yousef , Zahraei Seyed Mohsen , Karami Manoochehr , Yaseri Mehdi , Lotfizad Mojtaba , Holakouie‐Naieni Kourosh
Published: August 2020

Background

Early detection of outbreaks of transmissible diseases is essential for public health. This study aimed to determine the performance of the wavelet‐based outbreak detection method (WOD) in detecting outbreaks and to compare its performance with the Poisson regression‐based model and exponentially weighted moving average (EWMA) using data of simulated pertussis outbreaks in Iran.

Method

The data on suspected cases of pertussis from 25th February 2012 to 23rd March 2018 in Iran was used. The performance of the WOD (Daubechies 10 [db10] and Haar wavelets), Poisson regression‐based method, and EWMA Compared in terms of timeliness and detection of outbreak days using the simulation of different outbreaks. In the current study, two simulations were used, one based on retrospectively collected data (literature‐based) on pertussis cases and another one on a synthetic dataset created by the researchers. The sensitivity, specificity, false alarm, and false‐negative rate, positive and negative likelihood ratios, under receiver operating characteristics areas, and median timeliness were used to assess the performance of the methods.

Results

In a literature‐based outbreak simulation, the highest and lowest sensitivity, false negative in the detection of injected outbreaks were seen in db10, with sensitivity 0.59 (0.56‐0.62), and Haar wavelets with 0.57 (0.54‐0.60). In the researcher simulated data, the EWMA (K = 0.5) with sensitivity 0.92 (0.90‐0.94) had the best performance. About timeliness, the WOD methods showed the best performance in the early warning of the outbreak in both simulation approaches.

Conclusion

Performance of the WOD in the early alarming outbreaks was appropriate. However, this method would be best used along with other methods of public health surveillance.
Area under the curve achievement of once daily tobramycin in children with cystic fibrosis during clinical care
Authors: Brockmeyer Jake M. , Wise Russell T. , Burgener Elizabeth B. , Milla Carlos , Frymoyer Adam
Published: August 2020

Background

The area under the concentration‐time curve over 24 hours (AUC24) is frequently utilized to monitor tobramycin exposure in children with cystic fibrosis (CF). An understanding of exposure target achievement during clinical implementation of an AUC24 based approach in children is limited.

Methods

A retrospective chart review was performed in children with CF treated with once daily tobramycin and drug concentration monitoring at a pediatric CF center. During clinical care AUC24 was estimated using a traditional log‐linear regression approach (LLR). AUC24 was also estimated retrospectively using a pharmacokinetic model‐based Bayesian forecasting approach (BF). AUC24 achievement after both approaches were compared.

Results

In 77 treatment courses (mean age, 12.7 ± 5.0 years), a target AUC24 100 to 125 mg h/L was achieved after starting dose in 21 (27%) and after initial dose adjustment in 35 (45%). In the first 7 days of treatment, 24 (32%) required ≥3 dose adjustments, and the mean number of drug concentrations measured was 7.1 ± 3.2. Examination of a BF approach demonstrated adequate prediction of measured tobramycin concentrations (median bias −2.1% [95% CI −3.1 to −1.4]; median precision 7.6% [95% CI, 7.1%‐8.2%]). AUC24 estimates utilizing the BF approach were higher than the LLR approach with a mean difference of 6.4 mg h/L (95% CI, 4.8 to 8.0 mg h/L).

Conclusions

Achievement of a narrow AUC24 target is challenging during clinical care, and dose individualization is needed in most children with CF. Implementing a BF approach for estimating AUC24 in children with CF is supported.
Si/Ge (111) Semicoherent Interfaces: Responses to an In‐Plane Shear and Interactions with Lattice Dislocations
Authors: Xu Shuozhi , Li Yang , Chen Youping
Published: August 2020

Concurrent atomistic–continuum simulations are employed to study Si/Ge (111) semicoherent interfaces in terms of their responses to an in‐plane shear and interactions with lattice dislocations. Three types of Si/Ge interfaces, differing in interfacial structures and energy, are considered. Type I interface coincides with the shuffle‐set slip plane and contains a hexagonal network of edge dislocations. Type II and Type III interfaces both coincide with the glide‐set slip plane, yet they contain, respectively, a triangular and a hexagonal network of Shockley partial dislocations. The simulations show that among the three types of interfaces, 1) Type I interface is the least stable subject to an in‐plane shear and 2) Type III interface impedes the gliding of lattice dislocations the most significantly.
The Electronic Properties of Chlorine in GaN: An Ab Initio Study
Authors: Fujii Yusuke , Micheletto Ruggero , Alfieri Giovanni
Published: August 2020

Chlorine‐based reactive ion etching (RIE) is a fundamental processing step for the manufacturing of GaN semiconductor devices. As impurities can be unintentionally incorporated in the crystal during processing, the electronic properties of chlorine in GaN are investigated. Density functional theory calculations of substitutional Cl and related complexes (with a vacancy or a dopant) are carried out. It is found that Cl and its complexes explain the reported effects of Cl RIE‐treated GaN on hole density and ohmic contact resistivity.
Graphitization of Gallium‐Incorporated Carbon Nanofibers and Cones: In Situ and Ex Situ Transmission Electron Microscopy Studies
Authors: Paudel Jaisi Balaram , Sharma Subash , Elnobi Sahar , Abuelwafa Amr Attia , Yaakob Yazid , Kalita Golap , Tanemura Masaki
Published: August 2020

This study demonstrates graphitization directly through the amorphous carbon under the catalysis of a low‐melting‐point metal, gallium (Ga), by heating in a vacuum heater as well as by Joule heating during in situ transmission electron microscopy (TEM) operation. For the material system of the mixture of Ga nanoparticles (NPs) and amorphous carbon matrix, the graphitization temperature is determined to be about 600 °C for the first time. With increasing the temperature, evaporation and agglomeration of small Ga NPs start to occur together with the graphitization at around the places where Ga NPs would have been located at the surface region. In situ TEM experiment reveals the accelerated increase in electrical conductivity with structural change from amorphous to graphitization. Thus, the combination of the in situ and ex situ TEM observations is believed to be a lead step to understand deeper the graphitization process and provide information in nanoscale.
Mechanical Orientation of Fine Magnetic Particles in Powders by an External Magnetic Field: Simulation‐Based Optimization
Authors: Erokhin Sergey , Berkov Dmitry
Published: August 2020

A numerical algorithm for predicting the optimal conditions for the effective alignment of magnetic particles in dense powders during the compactization process using an externally applied field is presented. This task is especially important for the development of permanent magnets due to the fact that the alignment of anisotropy axes of nanocomposite grains increases both remanence and coercivity of magnetic materials. In contrast to previously known methods where the magnetic moment of each particle is assumed to be “fixed” with respect to the particle itself, the approach considers the (field‐dependent) deviation of this moment from the particle anisotropy axis that occurs even for magnetically “hard” particles possessing a strong mechanical contact. It is shown that this deviation leads to the existence of the optimal value of the applied field for which the particle orientation (or alignment) time is minimal. The influence of the external pressure and internal mechanical friction on the details of the compactization/orientation process is also studied.
Evaluation of Shewhart time‐between‐events‐and‐amplitude control charts for correlated data
Authors: Rahali Dorra , Castagliola Philippe , Taleb Hassen , Khoo Michael Boon Chong
Published: August 2020

In recent years, several techniques based on control charts have been developed for the simultaneous monitoring of the time interval T and the amplitude X of events, known as time‐between‐events‐and‐amplitude (TBEA) charts. However, the vast majority of the existing works have some limitations. First, they usually focus on statistics based on the ratio
, and second, they only investigate a reduced number of potential distributions, that is, the exponential distribution for T and the normal distribution for X. Moreover, until now, very few research papers have considered the potential dependence between T and X. In this paper, we investigate three different statistics, denoted as Z1, Z2, and Z3, for monitoring TBEA data in the case of three potential distributions (gamma, normal, and Weibull), for both T and X, using copulas as a mechanism to model the dependence. An illustrative example considering times between machine breakdowns and associated maintenance illustrates the use of TBEA control charts.
Successive and automated stable isotope analysis of CO2, CH4 and N2O paving the way for unmanned aerial vehicle‐based sampling
Authors: Leitner Simon , Hood‐Nowotny Rebecca , Watzinger Andrea
Published: August 2020

Rationale

Measurement of greenhouse gas (GHG) concentrations and isotopic compositions in the atmosphere is a valuable tool for predicting their sources and sinks, and ultimately how they affect Earth's climate. Easy access to unmanned aerial vehicles (UAVs) has opened up new opportunities for remote gas sampling and provides logistical and economic opportunities to improve GHG measurements.

Methods

This study presents synchronized gas chromatography/isotope ratio mass spectrometry (GC/IRMS) methods for the analysis of atmospheric gas samples (20‐mL  glass vessels) to determine the stable isotope ratios and concentrations of CO2, CH4 and N2O. To our knowledge there is no comprehensive GC/IRMS setup for successive measurement of CO2, CH4 and N2O analysis meshed with a UAV‐based sampling system. The systems were built using off‐the‐shelf instruments augmented with minor modifications.

Results

The precision of working gas standards achieved for δ13C and δ18O values of CO2 was 0.2‰ and 0.3‰, respectively. The mid‐term precision for δ13C and δ15N values of CH4 and N2O working gas standards was 0.4‰ and 0.3‰, respectively. Injection quantities of working gas standards indicated a relative standard deviation of 1%, 5% and 5% for CO2, CH4 and N2O, respectively. Measurements of atmospheric air samples demonstrated a standard deviation of 0.3‰ and 0.4‰ for the δ13C and δ18O values, respectively, of CO2, 0.5‰ for the δ13C value of CH4 and 0.3‰ for the δ15N value of N2O.

Conclusions

Results from internal calibration and field sample analysis, as well as comparisons with similar measurement techniques, suggest that the method is applicable for the stable isotope analysis of these three important GHGs. In contrast to previously reported findings, the presented method enables successive analysis of all three GHGs from a single ambient atmospheric gas sample.
Sustainable regional energy planning: The case of hydro
Authors: Rabe Marcin , Streimikiene Dalia , Drożdż Wojciech , Bilan Yuriy , Kasperowicz Rafal
Published: August 2020

The study is dedicated to analysis of sustainable regional energy planning challenge's in order to reach carbon‐free economy in 2050. The case study of hydropower development in selected region of Poland provides good example how to deal practically with identified sustainable regional energy planning problems to address restrictions of environmental requirements and natural conditions on the least costs hydropower generation planning in a given region. The aim of the article is to develop a model for optimizing hydropower production and to apply this model for selected region. The West Pomeranian region was selected for this case study, and the time range for planning is from 2019 to 2030. The selected region is particularly predestined for the production of renewable energy sources. Constructed model and obtained results for optimization of hydropower development in selected region is useful for fostering usage of renewable energy sources in Poland and moving forward towards carbon‐free economy target set by European Union for 2050.
Ensuring safe and consistent coengineering of cyber‐physical production systems: A case study
Authors: Tröls Michael , Mashkoor Atif , Demuth Andreas , Egyed Alexander
Published: August 2020

In today's engineering projects, companies continuously have to adapt their systems to changing customers or dynamic market requirements. This requires a flexible, iterative development process in which different parts of the system under construction are built and updated concurrently. However, concurrent engineering becomes quite challenging in domains where different engineering artifacts from different disciplines come into play, such as safety‐critical cyber‐physical systems, where the involved engineering artifacts are quite heterogeneous in nature. In such systems, it is of utmost importance that different artifacts remain consistent in order to guarantee a correctly functioning end product. In this article, we discuss our experiences (with a leading company working in the areas of production automation and product processing) in maintaining the consistency between electrical models and the corresponding software controller, when both are subject to continuous changes. The article discusses how we let engineers describe the relationships between electrical models and the corresponding software controller code in the form of links and consistency rules. Additionally, we demonstrate that how our approach, through a process of continuous consistency checking, notifies engineers about the erroneous impact of their changes in various engineering artifacts.
Europium (II)‐Doped All‐Inorganic CsPbBr3 Perovskite Solar Cells with Carbon Electrodes
Authors: Karunakaran Santhosh Kumar , Arumugam Gowri Manohari , Yang Wentao , Ge Sijie , Khan Saqib Nawaz , Mai Yaohua , Lin Xianzhong , Yang Guowei
Published: August 2020

All‐inorganic perovskite of CsPbBr3 thin‐films solar cells has attracted increasing interest in recent years due to its potential long‐term stability over the generally used hybrid perovskites. Herein, all‐inorganic CsPbBr3 perovskites are doped with Eu2+ to enhance the efficiency of perovskite solar cells (PVSCs). The perovskite films exhibit a better crystallinity with smooth morphology after the introduction of rare‐earth elements. Hence, the hole‐transport layer‐free device with presence of Eu2+ and low‐cost carbon electrode achieves both enhanced efficiency and stability. In particular, the power conversion efficiency (PCE) enhances from 5.66% to 7.28% with high VOC of 1.45 V by optimizing the doping concentration of Eu2+. In addition, the storage stability measurements reveal excellent performances of PCE without encapsulation in air with relative humidity of 70–80%. These results can pave changes in future inorganic PVSCs.
Dual factor third‐party biometric‐based authentication scheme using quantum one time passwords†
Authors: Sharma Mohit Kumar , Nene Manisha J.
Published: August 2020

One Time Passwords (OTP) are being widely used for authentication of user to access a number of services offered online. The security vulnerabilities in classical execution of OTP schemes are addressed using Quantum OTP (QOTP) scheme with user biometrics. This scheme requires sharing of user biometric data with every service provider. The chances of leakage of user biometrics increase with increase in number of entities holding the data. Further, loss of data by any entity compromises user identity for all other services. The work carried out in this article addresses the above‐mentioned challenges by incorporating a trusted third party which holds user biometric data and carries out authentication on its behalf. The proposed model continues leveraging upon inherent security benefits provided by Quantum Entanglement and Quantum Communication and utilizing user biometrics as authentication data. It modifies the QOTP scheme by carrying out mutual authentication for user and server against a particular transaction. The proposed model brings in the advantages of Single Sign On facility in terms of hardware to reduce infrastructure cost and No Secret Sharing of user biometric data with the servers to protect against rogue servers. The security analysis demonstrates the merit of the inherent procedures of the proposed work which leverage on the no‐cloning and quantum cryptography principles.
Extended Analyses of Iron Ore Sinter by Image Processing
Authors: Bückner Birgit , Mali Heinrich
Published: August 2020

The iron ore sinter quality is described by various parameters. The mineralogical and textural characteristics are obtained by image processing from microimages of polished sections. The image processing software VisuMet is adapted to analyze the mineral abundance and porosity of iron ore sinter. New algorithms are developed to calculate microstructural characteristics, like the pore size distribution and the effective thickness of sinter grains. The validation of the method using image processing is given by the description of three test series to estimate the systematic and analytical errors. The application to five industrial sinter samples is outlined. Ninety percent of all pores are smaller than 250 μm in equivalent diameter and the mean equivalent diameter ranges from 76 to 79 μm. The effective thickness, which is defined as the maximum distance between solid and nonsolid sinter material, varies between 120 and 368 μm. The area degradation algorithm of VisuMet is used to calculate the gradient between 30% and 80% of the degraded area. Dense sinter grains have a lower gradient than porous ones.
The role of chemical exposures in reducing the effectiveness of water–sanitation–hygiene interventions in Bangladesh, Kenya, and Zimbabwe
Authors: Kearns Joshua
Published: August 2020

The sustainable success of water, sanitation, and hygiene (WASH) interventions to reduce waterborne disease and promote public health in low‐income regions is uncertain. Recent large randomized controlled trials in Bangladesh, Kenya, and Zimbabwe revealed that traditional household WASH interventions are unlikely to reduce diarrhea or improve linear growth (i.e., reduce stunting) in infants and children—two important indicators of the effectiveness of WASH interventions. A possible factor contributing to the null results is that traditional WASH interventions control microbial pathogens but do not remove chemical toxicants. Exposure to many organic and inorganic chemical toxicants is associated with diarrheal symptoms, as well as with preterm birth and stunting. Many chemical toxicants have deleterious effects on the immune system, impairing the body's response to infectious diseases, and reducing the effectiveness of vaccinations. Globalization has led to rapid and largely unregulated import, production, use, and disposal without adequate treatment of large quantities of hazardous chemicals throughout the developing world, with profound effects on the environment and human health. Literature evidence from the past 10 to 15 years on putative and demonstrated chemical exposures in Bangladesh, Kenya, and Zimbabwe and the regions within the countries where the large WASH trials took place supports potential contribution(s) from chemical toxicants in the failure of traditional WASH interventions to relieve diarrhea and stunting. Mitigating exposures to organic and inorganic chemical immunotoxins through drinking water and other routes is likely to be a necessary‐but‐insufficient criterion for the sustainable success of WASH interventions.

This article is categorized under:

Engineering Water > Water, Health, and Sanitation

Engineering Water > Sustainable Engineering of Water
An accurate and explicit approach to modeling realistic hardening‐to‐softening transition effects of metals
Authors: Xu Zi‐Han , Zhan Lin , Wang Si‐Yu , Xi Hui‐Feng , Xiao Heng
Published: August 2020

A finite strain J2‐flow model of von Mises type for elastoplastic behaviors of metals is proposed with a new characterization of the evolving yield strength. It is intended for providing solutions to a few unresolved issues concerning a simultaneous simulation of realistic hardening and softening effects for metals up to failure. Such issues are concerned with three respects, namely, how to ensure that the simulation is accurate in the sense that sufficient uniaxial experimental data for both hardening and softening effects can be matched with no errors, how to ensure that the simulation is explicit in the sense that any implicit trial‐and‐error iterative procedures in identifying numerous parameters can be bypassed, and how to ensure that the simulation is of broad applicability in the sense that any given uniaxial data for metals can be automatically matched. With the new model proposed, solutions to such issues are obtained by presenting an accurate and explicit form of the yield strength function that automatically matches any given test data. Numerical examples with realistic hardening‐to‐softening transition effects are presented for the first time for the finite strain responses of both uniaxial stretching and simple shearing up to the eventual failure.
Magnetic deformation of super-Maxwell theory in supergravity
Authors: Antoniadis Ignatios , Derendinger Jean-Pierre , Jiang Hongliang , Tartaglino-Mazzucchelli Gabriele
Published: August 2020

Abstract

A necessary condition for partial breaking of $$ \mathcal{N} $$
N
= 2 global supersymmetry is the presence of nonlinear deformations of the field transformations which cannot be generated by background values of auxiliary fields. This work studies the simplest of these deformations which already occurs in $$ \mathcal{N} $$
N
= 1 global supersymmetry, and its coupling to supergravity. It can be viewed as an imaginary constant shift of the D-auxiliary real field of an abelian gauge multiplet. We show how this deformation describes the magnetic dual of a Fayet-Iliopoulos term, a result that remains valid in supergravity, using its new-minimal formulation. Local supersymmetry and the deformation induce a positive cosmological constant. Moreover, the deformed U(1) Maxwell theory coupled to supergravity describes upon elimination of the auxiliary fields the gauging of R-symmetry, realised by the Freedman model of 1976. To this end, we construct the chiral spinor multiplet in superconformal tensor calculus by working out explicitly its transformation rules and use it for an alternative description of the new-minimal supergravity coupled to a U(1) multiplet. We also discuss the deformed Maxwell theory in curved superspace.
NLO QCD+EW predictions for tHj and tZj production at the LHC
Authors: Pagani Davide , Tsinikos Ioannis , Vryonidou Eleni
Published: August 2020

Abstract

In this work we calculate the cross sections for the hadroproduction of a single top quark or antiquark in association with a Higgs (tHj) or Z boson (tZj) at NLO QCD+EW accuracy. In the case of tZj production we consider both the case of the Z boson undecayed and the complete final state tℓ+ℓ−j, including off-shell and non-resonant effects. We perform our calculation in the five-flavour-scheme (5FS), without selecting any specific production channel (s-, t- or tW associated). Moreover, we provide a more realistic estimate of the theory uncertainty by carefully including the differences between the four-flavour-scheme (4FS) and 5FS predictions. The difficulties underlying this procedure in the presence of EW corrections are discussed in detail. We find that NLO EW corrections are in general within the NLO QCD theory uncertainties only if the flavour scheme uncertainty (4FS vs. 5FS) is taken into account. For the case of tℓ+ℓ−j production we also investigate differences between NLO QCD+EW predictions and NLO QCD predictions matched with a parton shower simulation including multiple photon emissions.
Double-soft behavior of massless closed strings interacting with any number of closed string tachyons
Authors: Marotta Raffaele , Mojaza Matin
Published: August 2020

Abstract

We calculate the simultaneous double-soft limit of two massless closed strings scattering with any number of closed string tachyons to the subleading order at the tree level. The limit factorizes the scattering amplitude into a double-soft factor multiplying the pure tachyon subamplitude, suggesting a universal double-soft theorem for the massless closed string. We confirm an existing result for the double-soft graviton in an on-shell equivalent, but different form, while also establishing the double-soft factorization behavior of the string dilaton and of the Kalb-Ramond state, as well as the mixed graviton-dilaton case. We also show that the simultaneous and consecutive double-soft theorems are consistent with each other. We furthermore provide a complete field theory diagrammatic view on our result, which enables us in particular to establish a four-point interaction vertex for two tachyons and two massless closed string states, as well as the missing in field theory of three-point interaction of two massless closed string state and one tachyon.
A robust measure of event isotropy at colliders
Authors: Cesarotti Cari , Thaler Jesse
Published: August 2020

Abstract

We introduce a new event shape observable — event isotropy — that quantifies how close the radiation pattern of a collider event is to a uniform distribution. This observable is based on a normalized version of the energy mover’s distance, which is the minimum “work” needed to rearrange one radiation pattern into another of equal energy. We investigate the utility of event isotropy both at electron-positron colliders, where events are compared to a perfectly spherical radiation pattern, as well as at proton-proton colliders, where the natural comparison is to either cylindrical or ring-like patterns. Compared to traditional event shape observables like sphericity and thrust, event isotropy exhibits a larger dynamic range for high-multiplicity events. This enables event isotropy to not only distinguish between dijet and multijet processes but also separate uniform N-body phase space configurations for different values of N. As a key application of this new observable, we study its performance to characterize strongly-coupled new physics scenarios with isotropic collider signatures.
On catalyzed vacuum decay around a radiating black hole and the crisis of the electroweak vacuum
Authors: Hayashi Takumi , Kamada Kohei , Oshita Naritaka , Yokoyama Jun’ichi
Published: August 2020

Abstract

False vacuum decay is a key feature in quantum field theories and exhibits a distinct signature in the early Universe cosmology. It has recently been suggested that the false vacuum decay is catalyzed by a black hole (BH), which might cause the catastrophe of the Standard Model Higgs vacuum if primordial BHs are formed in the early Universe. We investigate vacuum phase transition of a scalar field around a radiating BH with taking into account the effect of Hawking radiation. We find that the vacuum decay rate slightly decreases in the presence of the thermal effect since the scalar potential is stabilized near the horizon. However, the stabilization effect becomes weak at the points sufficiently far from the horizon. Consequently, we find that the decay rate is not significantly changed unless the effective coupling constant of the scalar field to the radiation is extremely large. This implies that the change of the potential from the Hawking radiation does not help prevent the Standard Model Higgs vacuum decay catalyzed by a BH.
Heavy quark expansion for heavy hadron lifetimes: completing the $$ 1/{m}_b^3 $$ corrections
Authors: Mannel Th. , Moreno D. , Pivovarov A. A.
Published: August 2020

Abstract

We complete the calculation of the contributions from the dimension six operators in the heavy quark expansion for the total lifetime of heavy hadrons. We give the leading order expressions for the Wilson coefficients of the Darwin term ρD and the spin-orbit term ρLS.
More on Schrödinger holography
Authors: Golubtsova A. , Dimov H. , Iliev I. , Radomirov M. , Rashkov R. C. , Vetsov T.
Published: August 2020

Abstract

We find explicit solutions for giant magnons and spiky strings living on the Schrödinger space Schr5 × T1,1 and compute dispersion relations. The holographic dual field theory is conjectured to be a non-local dipole-deformed CFT at strong coupling. We find that the dependence between conserved charges in the dispersion relations is transcen- dental, which is quite different from the most symmetric case of spherical internal space. Keeping the squashing parameter b general allows us to take some limits and to compare our results to known cases.
A particle model with extra dimensions from coadjoint Poincaré symmetry
Authors: Barducci Andrea , Casalbuoni Roberto , Gomis Joaquim
Published: August 2020

Abstract

Starting from the coadjoint Poincaré algebra we construct a point particle relativistic model with an interpretation in terms of extra-dimensional variables. The starting coadjoint Poincaré algebra is able to induce a mechanism of dimensional reduction between the usual coordinates of the Minkowski space and the extra-dimensional variables which turn out to form an antisymmetric tensor under the Lorentz group. Analysing the dynamics of this model, we find that, in a particular limit, it is possible to integrate out the extra variables and determine their effect on the dynamics of the material point in the usual space time. The model describes a particle in D dimensions subject to a harmonic motion when one of the parameters of the model is negative. The result can be interpreted as a modification to the flat Minkowski metric with non trivial Riemann, Ricci tensors and scalar curvature.
New de Sitter solutions in ten dimensions and orientifold singularities
Authors: Córdova Clay , De Luca G. Bruno , Tomasiello Alessandro
Published: August 2020

Abstract

In previous work, we found ten-dimensional solutions to the supergravity equations of motion with a dS4 factor and O8-planes. We generalize this analysis and obtain other solutions in the same spirit, with an O8+ and an O6−. We examine our original solutions in more detail, focusing in particular on the O8− singularities and on the issues created by their boundary conditions. We also point out some previously known super- symmetric AdS solutions with the same local behavior at their O8− singularity.
Islands and Page curves for evaporating black holes in JT gravity
Authors: Hollowood Timothy J. , Kumar S. Prem
Published: August 2020

Abstract

The effect of a CFT shockwave on the entanglement structure of an eternal black hole in Jackiw-Teitelboim gravity, that is in thermal equilibrium with a thermal bath, is considered. The shockwave carries energy and entropy into the black hole and heats the black hole up leading to evaporation and the eventual recovery of equilibrium. We find an analytical description of the entire relaxational process within the semiclassical high temperature regime. If the shockwave is inserted around the Page time then several scenarios are possible depending on the parameters. The Page time can be delayed or hastened and there can be more than one transition. The final entropy saddle has a quantum extremal surface that generically starts inside the horizon but at some later time moves outside. In general, increased shockwave energy and slow evaporation rate favour the extremal surface to be inside the horizon. The shockwave also disrupts the scrambling properties of the black hole. The same analysis is then applied to a shockwave inserted into the extremal black hole with similar conclusions.
Leptogenesis from a U(1)D resonance
Authors: Chun Eung Jin , Dasgupta Arnab , Kang Sin Kyu
Published: August 2020

Abstract

We propose a novel mechanism to realize leptogenesis through the Breit- Wigner resonance of a dark U(1)D gauge boson ZD , which mediates lepton number vi- olating annihilations of dark matter (DM) in the context of the scotogenic model with a U(1)D . The processes occur out of equilibrium and DM freezes out later giving rise to the observed abundance. The CP violation required for leptogenesis can be achieved by the interference between tree-level t-channel scattering of DM and the subsequent 1-loop mediated by ZD , which arises due to the unremovable imaginary part of either the ZD propagator coming from its self-energy correction or the 1-loop giving rise to the effective coupling of $$ {Z}_D\overline{\nu}\nu $$

Z
D

ν
¯

ν
.
Magneto-thermal transport implies an incoherent Hall conductivity
Authors: Amoretti Andrea , Brattan Daniel K. , Magnoli Nicodemo , Scanavino Marcello
Published: August 2020

Abstract

We consider magnetohydrodynamics with an external magnetic field. We find that in general one must allow for a non-zero incoherent Hall conductivity to correctly describe the DC longitudinal and Hall thermal conductivities beyond order zero in the magnetic field expansion. We apply our result to the dyonic black hole, determining the incoherent Hall conductivity in that case, and additionally prove that the existence of this transport coefficient leads to a significantly better match between the hydrodynamic and AC thermo-electric correlators.
Entropy production and entropic attractors in black hole fusion and fission
Authors: Andrade Tomás , Emparan Roberto , Jansen Aron , Licht David , Luna Raimon , Suzuki Ryotaku
Published: August 2020

Abstract

We study how black hole entropy is generated and the role it plays in several highly dynamical processes: the decay of unstable black strings and ultraspinning black holes; the fusion of two rotating black holes; and the subsequent fission of the merged system into two black holes that fly apart (which can occur in dimension D ≥ 6, with a mild violation of cosmic censorship). Our approach uses the effective theory of black holes at D → ∞, but we expect our main conclusions to hold at finite D. Black hole fusion is highly irreversible, while fission, which follows the pattern of the decay of black strings, generates comparatively less entropy. In 2 → 1 → 2 black hole collisions an intermediate, quasi-thermalized state forms that then fissions. This intermediate state erases much of the memory of the initial states and acts as an attractor funneling the evolution of the collision towards a small subset of outgoing parameters, which is narrower the closer the total angular momentum is to the critical value for fission. Entropy maximization provides a very good guide for predicting the final outgoing states. Along our study, we clarify how entropy production and irreversibility appear in the large D effective theory. We also extend the study of the stability of new black hole phases (black bars and dumbbells). Finally, we discuss entropy production through charge diffusion in collisions of charged black holes.
CT volume of enhancement of disease (VED) can predict the early response to treatment and overall survival in patients with advanced HCC treated with sorafenib
Authors: Colagrande S. , Calistri L. , Campani C. , Dragoni G. , Lorini C. , Nardi C. , Castellani A. , Marra F.
Published: August 2020

Objectives

To analyse the predictive value of the volume of enhancement of disease (VED), based on the CT arterial enhancement coefficient (ΔArt%), in the evaluation of the sorafenib response in patients with advanced hepatocellular carcinoma (HCC).

Methods

Patients with sorafenib-treated advanced HCC, who underwent a multiphase contrast-enhanced CT before (T0) and after 60–70 days of starting therapy (T1), were included. The same target lesions utilised for the response evaluation according to modified Response Evaluation Criteria in Solid Tumors criteria were retrospectively used for the ΔArt% calculation ([(HUarterial phase − HUunenhanced phase) / HUunenhanced phase] × 100). ΔArt% was weighted for the lesion volume to obtain the VED. We compared VEDT0 and VEDT1 values in patients with clinical benefit (CB) or progressive disease (PD). The impact of VED, ancillary imaging findings, and blood chemistries on survival probability was evaluated.

Results

Thirty-two patients (25 men, mean age 65.8 years) analysed between 2012 and 2016 were selected. At T1, 8 patients had CB and 24 had PD. VEDT0 was > 70% in 8/8 CB patients compared with 12/24 PD patients (p = 0.011). Patients with VEDT0 > 70% showed a significantly higher median survival than those with lower VEDT0 (451.5 days vs. 209.5 days, p = 0.032). Patients with VEDT0 > 70% and alpha-fetoproteinT0 ≤ 400 ng/ml had significantly longer survival than all other three combinations. In multivariate analysis, VEDT0 > 70% emerged as the only factor independently associated with survival (p = 0.037).

Conclusion

In patients with advanced HCC treated with sorafenib, VED is a novel radiologic parameter obtained by contrast-enhanced CT, which could be helpful in selecting patients who are more likely to respond to sorafenib, and with a longer survival.

Key Points

• To achieve the best results of treatment with sorafenib in advanced HCC, a strict selection of patients is needed.

• New radiologic parameters predictive of the response to sorafenib would be essential.

• Volume of enhancement of disease (VED) is a novel radiologic parameter obtained by contrast-enhanced CT, which could be helpful in selecting patients who are more likely to respond to therapy, and with a longer survival.