bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi-objective particle swarm optimization with random immigrants
Authors: Ünal Ali Nadi , Kayakutlu Gülgün
Published: June 2020

Complex problems of the current business world need new approaches and new computational algorithms for solution. Majority of the issues need analysis from different angles, and hence, multi-objective solutions are more widely used. One of the recently well-accepted computational algorithms is Multi-objective Particle Swarm Optimization (MOPSO). This is an easily implemented and high time performance nature-inspired approach; however, the best solutions are not found for archiving, solution updating, and fast convergence problems faced in certain cases. This study investigates the previously proposed solutions for creating diversity in using MOPSO and proposes using random immigrants approach. Application of the proposed solution is tested in four different sets using Generational Distance, Spacing, Error Ratio, and Run Time performance measures. The achieved results are statistically tested against mutation-based diversity for all four performance metrics. Advantages of this new approach will support the metaheuristic researchers.
Hyperspectral remote sensing for extraction of soil salinization in the northern region of Ningxia
Authors: Abd El-Hamid Hazem T. , Hong Guan
Published: June 2020

Soil salinization affects negatively on agricultural productivity in the semiarid region of Ningxia. In this study, the performance of inversion model to determine soil salinization was assessed using some analysis and reflectance of wavelength. About 42 vegetation samples and 42 soil samples were collected for model extraction. Hyper-spectral data processing method was used to analyze spectral characteristics of different levels of salinization area vegetation. Spectral data were transformed in 16 different approaches, including root mean squares, logarithm, inversion logarithm, and first-order differentiation. After the transformation, the obtained soil and vegetation characteristics spectra correlate well with soil salt content, built soil index, and many vegetation indices. Nonlinear regression was employed to establish soil salinization remote sensing monitoring model. By comparing various spectral transformations, the first-order differential of soil spectral was the most sensitive to soil salinization degrees. The model of the current research was based on salinity index (SI) and improved soil-adjusted vegetation index (MSAVI). The correlation between simulated values and measured values was 0.758. Therefore, remote sensing monitoring derived from MSAVI–SI can greatly improve the dynamic and periodical monitoring of soil salinity in the study area.
Streaming statistical models via Merge & Reduce
Authors: Geppert Leo N. , Ickstadt Katja , Munteanu Alexander , Sohler Christian
Published: June 2020

Merge & Reduceis a general algorithmic scheme in the theory of data structures. Its main purpose is to transform static data structures—that support only queries—into dynamic data structures—that allow insertions of new elements—with as little overhead as possible. This can be used to turn classic offline algorithms for summarizing and analyzing data into streaming algorithms. We transfer these ideas to the setting of statistical data analysis in streaming environments. Our approach is conceptually different from previous settings where Merge & Reduce has been employed. Instead of summarizing the data, we combine the Merge & Reduce framework directly with statistical models. This enables performing computationally demanding data analysis tasks on massive data sets. The computations are divided into small tractable batches whose size is independent of the total number of observationsn. The results are combined in a structured way at the cost of a bounded$$O(\log n)$$O(logn)factor in their memory requirements. It is only necessary, though nontrivial, to choose an appropriate statistical model and designmergeandreduceoperations on a casewise basis for the specific type of model. We illustrate our Merge & Reduce schemes on simulated and real-world data employing (Bayesian) linear regression models, Gaussian mixture models and generalized linear models.
Service-oriented high-performance human resource practices and employee service performance: A test of serial mediation and moderation models
Authors: Gürlek Mert , Uygur Akyay
Published: June 2020

This research aims to reveal how and under what conditions service-oriented high-performance human resource practices (HR) influence employee service performance (ESP). Data were gathered from full-time hotel employees and line managers. In total, 1,525 questionnaire forms were acquired. While respondent employees had filled in the questionnaire form containing independent, mediator, and moderator variables, line managers filled in the questionnaire form containing the dependent variable. The research results demonstrate that HR attributions, trust in the organization, and affective commitment serially mediate the relationship between service-oriented high-performance HR practices and ESP. In addition, the results point out the moderating roles of person–supervisor fit and person–vocation fit. As a result, the current research contributes to the literature by way of revealing how and under what conditions the service-oriented high-performance HR practices affect ESP.
Activity profile of two 5-nitroindazole derivatives over the moderately drug-resistant Trypanosoma cruzi Y strain (DTU TcII): in vitro and in vivo studies
Authors: Fonseca-Berzal Cristina , da Silva Cristiane França , Batista Denise da Gama Jaen , de Oliveira Gabriel Melo , Cumella José , Batista Marcos Meuser , Peres Raiza Brandão , Silva da Gama Nefertiti Aline , Escario José A. , Gómez-Barrio Alicia , Arán Vicente J. , Soeiro Maria de Nazaré Correia
Published: June 2020

In previous studies, we have identified several families of 5-nitroindazole derivatives as promising antichagasic prototypes. Among them, 1-(2-aminoethyl)-2-benzyl-5-nitro-1,2-dihydro-3H-indazol-3-one, (hydrochloride) and 1-(2-acetoxyethyl)-2-benzyl-5-nitro-1,2-dihydro-3H-indazol-3-one (compounds 16 and 24, respectively) have recently shown outstanding activity in vitro over the drug-sensitive Trypanosoma cruzi CL strain (DTU TcVI). Here, we explored the activity of these derivatives against the moderately drug-resistant Y strain (DTU TcII), in vitro and in vivo. The outcomes confirmed their activity over replicative forms, showing IC50 values of 0.49 (16) and 5.75 μm (24) towards epimastigotes, 0.41 (16) and 1.17 μm (24) against intracellular amastigotes. These results, supported by the lack of toxicity on cardiac cells, led to better selectivities than benznidazole (BZ). Otherwise, they were not as active as BZ in vitro against the non-replicative form of the parasite, i.e. bloodstream trypomastigotes. In vivo, acute toxicity assays revealed the absence of toxic events when administered to mice. Moreover, different therapeutic schemes pointed to their capability for decreasing the parasitaemia of T. cruzi Y acute infected mice, reaching up to 60% of reduction at the peak day as monotherapy (16), 79.24 and 91.11% when 16 and 24 were co-administered with BZ. These combined therapies had also a positive impact over the mortality, yielding survivals of 83.33 and 66.67%, respectively, while untreated animals reached a cumulative mortality of 100%. These findings confirm the 5-nitroindazole scaffold as a putative prototype for developing novel drugs potentially applicable to the treatment of Chagas disease and introduce their suitability to act in combination with the reference drug.
The mechanisms of sorafenib resistance in hepatocellular carcinoma: theoretical basis and therapeutic aspects
Authors: Tang Weiwei , Chen Ziyi , Zhang Wenling , Cheng Ye , Zhang Betty , Wu Fan , Wang Qian , Wang Shouju , Rong Dawei , Reiter F. P. , De Toni E. N. , Wang Xuehao
Published: June 2020

Sorafenib is a multikinase inhibitor capable of facilitating apoptosis, mitigating angiogenesis and suppressing tumor cell proliferation. In late-stage hepatocellular carcinoma (HCC), sorafenib is currently an effective first-line therapy. Unfortunately, the development of drug resistance to sorafenib is becoming increasingly common. This study aims to identify factors contributing to resistance and ways to mitigate resistance. Recent studies have shown that epigenetics, transport processes, regulated cell death, and the tumor microenvironment are involved in the development of sorafenib resistance in HCC and subsequent HCC progression. This study summarizes discoveries achieved recently in terms of the principles of sorafenib resistance and outlines approaches suitable for improving therapeutic outcomes for HCC patients.
The interactions between cGAS-STING pathway and pathogens
Authors: Cheng Zhangliang , Dai Tong , He Xuelin , Zhang Zhengkui , Xie Feng , Wang Shuai , Zhang Long , Zhou Fangfang
Published: June 2020

Cytosolic DNA is an indicator of pathogen invasion or DNA damage. The cytosolic DNA sensor cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) synthase (cGAS) detects DNA and then mediates downstream immune responses through the molecule stimulator of interferon genes (STING, also known as MITA, MPYS, ERIS and TMEM173). Recent studies focusing on the roles of the cGAS-STING pathway in evolutionary distant species have partly sketched how the mammalian cGAS-STING pathways are shaped and have revealed its evolutionarily conserved mechanism in combating pathogens. Both this pathway and pathogens have developed sophisticated strategies to counteract each other for their survival. Here, we summarise current knowledge on the interactions between the cGAS-STING pathway and pathogens from both evolutionary and mechanistic perspectives. Deeper insight into these interactions might enable us to clarify the pathogenesis of certain infectious diseases and better harness the cGAS-STING pathway for antimicrobial methods.
The zoonotic pathogen Leptospira interrogans mitigates environmental stress through cyclic-di-GMP-controlled biofilm production
Authors: Thibeaux Roman , Soupé-Gilbert Marie-Estelle , Kainiu Malia , Girault Dominique , Bierque Emilie , Fernandes Julien , Bähre Heike , Douyère Anthony , Eskenazi Nicolas , Vinh Joëlle , Picardeau Mathieu , Goarant Cyrille
Published: June 2020

The zoonotic bacterium Leptospira interrogans is the aetiological agent of leptospirosis, a re-emerging infectious disease that is a growing public health concern. Most human cases of leptospirosis result from environmental infection. Biofilm formation and its contribution to the persistence of virulent leptospires in the environment or in the host have scarcely been addressed. Here, we examined spatial and time-domain changes in biofilm production by L. interrogans. Our observations showed that biofilm formation in L. interrogans is a highly dynamic process and leads to a polarized architecture. We notably found that the biofilm matrix is composed of extracellular DNA, which enhances the biofilm’s cohesiveness. By studying L. interrogans mutants with defective diguanylate cyclase and phosphodiesterase genes, we show that biofilm production is regulated by intracellular levels of bis-(3′–5′)-cyclic dimeric guanosine monophosphate (c-di-GMP) and underpins the bacterium’s ability to withstand a wide variety of simulated environmental stresses. Our present results show how the c-di-GMP pathway regulates biofilm formation by L. interrogans, provide insights into the environmental persistence of L. interrogans and, more generally, highlight leptospirosis as an environment-borne threat to human health.
Somatic genetic aberrations in benign breast disease and the risk of subsequent breast cancer
Authors: Zeng Zexian , Vo Andy , Li Xiaoyu , Shidfar Ali , Saldana Paulette , Blanco Luis , Xuei Xiaoling , Luo Yuan , Khan Seema A. , Clare Susan E.
Published: June 2020

It is largely unknown how the development of breast cancer (BC) is transduced by somatic genetic alterations in the benign breast. Since benign breast disease is an established risk factor for BC, we established a case-control study of women with a history of benign breast biopsy (BBB). Cases developed BC at least one year after BBB and controls did not develop BC over an average of 17 years following BBB. 135 cases were matched to 69 controls by age and type of benign change: non-proliferative or proliferation without atypia (PDWA). Whole-exome sequencing (WES) was performed for the BBB. Germline DNA (available from n = 26 participants) was utilized to develop a mutation-calling pipeline, to allow differentiation of somatic from germline variants. Among the 204 subjects, two known mutational signatures were identified, along with a currently uncatalogued signature that was significantly associated with triple negative BC (TNBC) (p = 0.007). The uncatalogued mutational signature was validated in 109 TNBCs from TCGA (p = 0.001). Compared to non-proliferative samples, PDWA harbors more abundant mutations at PIK3CA pH1047R (p < 0.001). Among the 26 BBB whose somatic copy number variation could be assessed, deletion of MLH3 is significantly associated with the mismatch repair mutational signature (p < 0.001). Matched BBB-cancer pairs were available for ten cases; several mutations were shared between BBB and cancers. This initial study of WES of BBB shows its potential for the identification of genetic alterations that portend breast oncogenesis. In future larger studies, robust personalized breast cancer risk indicators leading to novel interception paradigms can be assessed.
Characterizing dysbiosis of gut microbiome in PD: evidence for overabundance of opportunistic pathogens
Authors: Wallen Zachary D. , Appah Mary , Dean Marissa N. , Sesler Cheryl L. , Factor Stewart A. , Molho Eric , Zabetian Cyrus P. , Standaert David G. , Payami Haydeh
Published: June 2020

In Parkinson’s disease (PD), gastrointestinal features are common and often precede the motor signs. Braak and colleagues proposed that PD may start in the gut, triggered by a pathogen, and spread to the brain. Numerous studies have examined the gut microbiome in PD; all found it to be altered, but found inconsistent results on associated microorganisms. Studies to date have been small (N = 20 to 306) and are difficult to compare or combine due to varied methodology. We conducted a microbiome-wide association study (MWAS) with two large datasets for internal replication (N = 333 and 507). We used uniform methodology when possible, interrogated confounders, and applied two statistical tests for concordance, followed by correlation network analysis to infer interactions. Fifteen genera were associated with PD at a microbiome-wide significance level, in both datasets, with both methods, with or without covariate adjustment. The associations were not independent, rather they represented three clusters of co-occurring microorganisms. Cluster 1 was composed of opportunistic pathogens and all were elevated in PD. Cluster 2 was short-chain fatty acid (SCFA)-producing bacteria and all were reduced in PD. Cluster 3 was carbohydrate-metabolizing probiotics and were elevated in PD. Depletion of anti-inflammatory SCFA-producing bacteria and elevated levels of probiotics are confirmatory. Overabundance of opportunistic pathogens is an original finding and their identity provides a lead to experimentally test their role in PD.
Speech-based characterization of dopamine replacement therapy in people with Parkinson’s disease
Authors: Norel R. , Agurto C. , Heisig S. , Rice J. J. , Zhang H. , Ostrand R. , Wacnik P. W. , Ho B. K. , Ramos V. L. , Cecchi G. A.
Published: June 2020

People with Parkinson’s (PWP) disease are under constant tension with respect to their dopamine replacement therapy (DRT) regimen. Waiting too long between doses results in more prominent symptoms, loss of motor function, and greater risk of falling per step. Shortened pill cycles can lead to accelerated habituation and faster development of disabling dyskinesias. The Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) is the gold standard for monitoring Parkinson’s disease progression but requires a neurologist to administer and therefore is not an ideal instrument to continuously evaluate short-term disease fluctuations. We investigated the feasibility of using speech to detect changes in medication states, based on expectations of subtle changes in voice and content related to dopaminergic levels. We calculated acoustic and prosodic features for three speech tasks (picture description, reverse counting, and diadochokinetic rate) for 25 PWP, each evaluated “ON” and “OFF” DRT. Additionally, we generated semantic features for the picture description task. Classification of ON/OFF medication states using features generated from picture description, reverse counting and diadochokinetic rate tasks resulted in cross-validated accuracy rates of 0.89, 0.84, and 0.60, respectively. The most discriminating task was picture description which provided evidence that participants are more likely to use action words in ON than in OFF state. We also found that speech tempo was modified by DRT. Our results suggest that automatic speech assessment can capture changes associated with the DRT cycle. Given the ease of acquiring speech data, this method shows promise to remotely monitor DRT effects.
Mechanical unfolding of a knotted protein unveils the kinetic and thermodynamic consequences of threading a polypeptide chain
Authors: Rivera Maira , Hao Yuxin , Maillard Rodrigo A. , Baez Mauricio
Published: June 2020

Knots are remarkable topological features in nature. The presence of knots in crystallographic structures of proteins have stimulated considerable research to determine the kinetic and thermodynamic consequences of threading a polypeptide chain. By mechanically manipulating MJ0366, a small single domain protein harboring a shallow trefoil knot, we allow the protein to refold from either the knotted or the unknotted denatured state to characterize the free energy profile associated to both folding pathways. By comparing the stability of the native state with reference to the knotted and unknotted denatured state we find that knotting the polypeptide chain of MJ0366 increase the folding energy barrier in a magnitude close to the energy cost of forming a knot randomly in the denatured state. These results support that a protein knot can be formed during a single cooperative step of folding but occurs at the expenses of a large increment on the free energy barrier.
Influence of the long-term use of oral hygiene products containing stannous ions on the salivary microbiome – a randomized controlled trial
Authors: Anderson A. C. , Al-Ahmad A. , Schlueter N. , Frese C. , Hellwig E. , Binder N.
Published: June 2020

Oral hygiene products containing tin are suitable to prevent erosive tooth wear, yet effects on the oral microbiota are not known yet. Therefore, this study determined the salivary microbiome of 16 participants using products with stannous ions for three years (TG) compared with a control group (CG) to assess their influence on the microbiota. Participants were included in a randomized controlled clinical trial (RCT) with biannual visits. Illumina Miseq sequencing revealed as most abundant genera: Streptococcus (TG 14.3%; CG 13.0%), Veillonella (TG 11.3%; CG 10.9%), Prevotella (TG 7.0%; CG 9.8%), Haemophilus (TG 6.6%; CG 7.2%), Porphyromonas (TG 5.9%, CG 5.1%), Leptotrichia (TG 5.8%; CG 4.9%), Actinomyces (TG 4.0%; CG 4.6%) and Neisseria (TG 5.4%; CG 4.2%). Beta-Diversity was not significantly different between groups at both time points, although significant differences between groups were found for certain taxa after three years. The genus Prevotella was found in higher abundance in CG whereas Neisseria and Granulicatella, health-associated taxa, were found more abundantly in TG. Salivary microbiota after three years reflected a composition associated with oral health, hence continual use as a preventive measure for dental erosion can be considered safe and benefitting oral health for patients with a high risk of erosion.
An Incremental Voltage Difference Based Technique for Online State of Health Estimation of Li-ion Batteries
Authors: Naha Arunava , Han Seongho , Agarwal Samarth , Guha Arijit , Khandelwal Ashish , Tagade Piyush , Hariharan Krishnan S. , Kolake Subramanya Mayya , Yoon Jongmoon , Oh Bookeun
Published: June 2020

Accurate state of health (SOH) estimation of rechargeable batteries is important for the safe and reliable operation of electric vehicles (EVs), smart phones, and other battery operated systems. We propose a novel method for accurate SOH estimation which does not necessarily need full charging data. Using only partial charging data during normal usage, 10 derived voltage values ($${v}_{sei}$$vsei) are collected. The initial $${v}_{sei}$$vsei point is fixed and then for every 1.5% increase in the Coulomb counting, other points are selected. The difference between the $${v}_{sei}$$vsei values ($$\Delta {v}_{sei}$$Δvsei) and the average temperature during the charging form the feature vector at different SOH levels. The training data set is prepared by extrapolating the charging voltage curves for the complete SOH range using initial 400 cycles of data. The trained artificial neural network (ANN) based on the feature vector and SOH values can be used in any battery management system (BMS) with a time complexity of only $$O({n}^{4})$$O(n4). Less than 1% mean absolute error (MAE) for the test cases has been achieved. The proposed method has a moderate training data requirement and does not need any knowledge of previous SOH, state of charge (SOC) vs. OCV relationship, and absolute SOC value.
Using human in vitro transcriptome analysis to build trustworthy machine learning models for prediction of animal drug toxicity
Authors: Gardiner Laura-Jayne , Carrieri Anna Paola , Wilshaw Jenny , Checkley Stephen , Pyzer-Knapp Edward O. , Krishna Ritesh
Published: June 2020

During the development of new drugs or compounds there is a requirement for preclinical trials, commonly involving animal tests, to ascertain the safety of the compound prior to human trials. Machine learning techniques could provide anin-silicoalternative to animal models for assessing drug toxicity, thus reducing expensive and invasive animal testing during clinical trials, for drugs that are most likely to fail safety tests. Here we present a machine learning model to predict kidney dysfunction, as a proxy for drug induced renal toxicity, in rats. To achieve this, we use inexpensive transcriptomic profiles derived from human cell lines after chemical compound treatment to train our models combined with compound chemical structure information. Genomics data due to its sparse, high-dimensional and noisy nature presents significant challenges in building trustworthy and transparent machine learning models. Here we address these issues by judiciously building feature sets from heterogenous sources and coupling them with measures of model uncertainty achieved through Gaussian Process based Bayesian models. We combine the use of insight into the feature-wise contributions to our predictions with the use of predictive uncertainties recovered from the Gaussian Process to improve the transparency and trustworthiness of the model.
Effect of lacquer decoration on VOCs and odor release from P. neurantha (Hemsl.) Gamble
Authors: Wang Qifan , Zeng Bin , Shen Jun , Wang Huiyu
Published: June 2020

The problem of odor caused by solid wood and its lacquer finish is increasingly serious. In this study, gas chromatography–mass spectrometry/olfactometry is used to analyze the volatile organic compounds and odor-active substances released from Phoebe neurantha (Hemsl.) Gamble lacquered with three types of lacquers, which is helpful in solving furniture’s odor problem. The results show that olefin emission of the three types of lacquer coating for P. neurantha (Hemsl.) Gamble decreases by more than 90% but that total volatile organic compound release increases. Among these, polyurethane (PU) lacquer could lead to a sharp increase of ester and aromatic hydrocarbons. Waterborne lacquer also releases numerous esters and alcohol compounds. Ultraviolet (UV)-curable lacquer has the greatest inhibitory effect on alcohols, aldehydes, and ketones and does not release esters or other compounds, but the release of toluene increases sharply. Benzaldehyde, toluene, and 1,3-dimethylbenzene are identified as key odor characteristic compounds of P. neurantha (Hemsl.) Gamble. Aromatic and fruity are the main odor characteristics of P. neurantha and three types of lacquer decoration studied. The overall odor intensity increases with lacquer treatment, especially PU lacquer. Among them, UV lacquer has the lowest overall odor intensity.
Automated determination ofn-cyanobiphenyl andn-cyanobiphenyl binary mixtures elastic constants in the nematic phase from molecular simulation
Authors: Shi Jiale , Sidky Hythem , Whitmer Jonathan K.
Published: June 2020

This work explores new techniques in molecular simulation which can be used to precisely determine and engineer elastic properties of liquid crystals for new applications.
Using low cost open-face passive samplers to sample PM concentration and elemental composition in childcare facilities
Authors: Wang Zhong-Min , Zhou Yixin , Gaspar Fraser W. , Bradman Asa
Published: June 2020

Effective, low noise and low-cost samplers for airborne particulate matter (PM) in indoor environments are needed.
Polyacrylic acid coated nanoparticles elicit endothelial cell apoptosis and diminish vascular relaxation inex vivoperfused iliac arteries of the cane toad (Rhinella marina)
Authors: Ortega Van A. , Cameron Melissa S. , Stafford James L. , Goss Greg G. , Donald John A. , Schultz Aaron G.
Published: June 2020

Cane toad iliac arteries were perfusedex vivowith polyacrylic acid coated nanoparticles. Nanoparticle uptake was observed in both endothelial and vascular smooth muscle cells, eliciting endothelial cell apoptosis and diminished vascular relaxation.
Mixed conductive composites for ‘Low-Temperature’ thermo-chemical CO2 splitting and syngas generation
Authors: Jiang Qiongqiong , Gao Yunfei , Haribal Vasudev Pralhad , Qi He , Liu Xingbo , Hong Hui , Jin Hongguang , Li Fanxing
Published: June 2020

An effective strategy to design platinum group metal (PGM) free redox catalysts for “low temperature” CO2 splitting followed with methane partial oxidation was proposed and validated.
Research on the optimised transceiver impedances for low‐voltage broadband PLC system
Authors: Zhang Hui
Published: June 2020

The design of transceiver impedances is very important to improve the performance of the power line communication (PLC) system. In this study, it infers an expression of signal‐to‐noise ratio (SNR) related to transceiver impedances for broadband PLCs, and the optimal transceiver impedances are obtained by solving a maximisation problem. By the comparison of the SNR of PLC system with the proposed transceiver impedances and only optimised transmitter or receiver impedance, the conclusions are derived that the PLC system performance with the proposed transceiver impedances is better and the receiver impedance has a greater influence on the performance of the PLC system. To verify the advantage of the optimal transceiver impedances proposed in this study, the authors also make the comparison with the other two kinds of transceiver impedance optimisation methods by simulating SNR and transmission rate of the PLC system. The results show that in theory, the SNR and channel capacity of PLC system ca, maximally increase by 15 dB and 50 Mbits/s, respectively, using the proposed transceiver impedances by comparing with the other two impedance optimisation methods, which proves that the proposed transceiver impedances in this study can obtain the better performance of the PLC system.
Encryption scheme against eavesdropper collusion in wireless multi‐user network
Authors: Huang Ying , Lei Jing , Li Wei
Published: June 2020

In order to resist eavesdropper collusion attack in wireless multi‐user network, the authors propose a distributed physical layer encryption (DPLE) scheme with energy‐efficient design. The encryption is embedded into rateless coding at both user nodes and relay node. Meanwhile, data frame permutation is added at the relay for increasing randomness. It is noteworthy that the secret key is used as the seed of random number generator, which controls the encoding process and permutation. At receiver, the decryption is united with decoding process without any extra cost, which makes DPLE special in the field of lightweight security. There are two cases considered in security analysis for resisting collusion attack: without error and with error. Typical results are time complexity and attack success probability, respectively. Furthermore, the evaluation for algorithm implementation is investigated. The theoretic result and simulation show that the proposed scheme can combat colluding eavesdroppers by high complexity and very low attack success probability. Moreover, lower computation cost is achieved.
Integrated receiver with high misalignment tolerance used in dynamic wireless charging
Authors: Xia Nenghong , Yuan Zhipeng , Zhu Yimin , Wang Yueyue
Published: June 2020

Misalignments between the transmitter and receiver coils would in some cases lead to a significant decline in transmission power and efficiency in the wireless power transfer system. This study presents an integrated two‐layer receiver to improve the tolerance of horizontal misalignment. On the lower layer of the integrated receiver, two coplanar spiral coils, which are decoupled and work as the auxiliary repeater, are designed to help keep a stable power transmission between transmitter coils on the track and the main receiver coil on the upper layer. Then, the optimisation model based on the Bayesian algorithm is established for the proposed receiver structure and some key parameters are optimised. A sensor‐coil‐based positioning approach is also proposed to achieve on–off control of the transmitter coils. The simulation results show that the system based on the optimised integrated receiver has a stable output power with a variation lower than 13.17%. Two 300 W dynamic charging prototypes based on the integrated receiver and conventional spiral receiver, respectively, have been developed to verify the effectiveness of the proposed design and the optimisation method. The experimental results match well with the simulation results.
Modelling of switched reluctance machines
Authors: Davarpanah Gholamreza , Mohammadi Sajjad , Kirtley James L.
Published: June 2020

Analytical models are powerful tools in the preliminary design of electric machines. In this study, a flux‐tube model is proposed for switched reluctance machines, in which all the flux paths and the corresponding elements are accurately calculated, iron saturation is intelligently taken into account and formulas are generally developed to attain a continuous model for any range of design parameters. The inductances, flux linkages, torque–angle, maximum torque–current, mean torque–current characteristics are extracted. The special structure of the developed model enables us to extract the air‐gap flux density distribution of the machine. Also, finite‐element analysis is used in the analyses and evaluation of the model. Finally, the machine has been prototyped by which torque–angle curve and open‐loop characteristics are obtained experimentally to evaluate the model. Superiorities of the proposed framework over the previous approaches are demonstrated as well.
Development and optimisation of hepatitis B recombinant antigen loaded chitosan nanoparticles as an adjuvant using the response surface methodology
Authors: Mehrabi Mohsen , Sadeghi‐Soureh Shima , Mohammadpour Dounighi Naser , Rezayat Seyed Mahdi , Doroud Delaram , Khoobi Mehdi , Amani Amir
Published: June 2020

The main purpose of this Letter was to develop and optimise recombinant hepatitis B antigen‐loaded chitosan nanoparticles (rHBsAg‐CS NPs) as a new adjuvant for hepatitis B vaccine through designing by response surface methodology (RSM). The NPs were prepared by employing ionic gelation technique. RSM was utilised by selecting the independent variablesincluding the concentration of CS, tripolyphosphate and antigen concentration as well as pH and homogenisation speed to obtain maximum encapsulation efficiency (EE) and loading capacity (LC). EE and LC of the optimised preparation were 93.2 ± 1.1 and 25.6 ± 1.38%, respectively. Optimised NPs showed spherical shape, particle size of 187 ± 14 nm and positive zeta potential (+31.3 ± 1.5 mV). In vitro release profile of optimised formulation revealed an initial burst, followed by a slow sustained antigen release. Cell viability assay indicated that the toxicity of NPs was concentration‐dependent. SDS‐PAGE analysis confirmed the structural stability and integrity of the released antigen. ELISA and Ouchterlony double immunodiffusion tests of released antigen showed that the antigenicity was preserved during the process of NP formation.
Oxidative properties and utility of fabricated MnSiO3 nanoparticles for colorimetric detection of iron (II) in water samples
Authors: Wang Tao , Jiang Haoran , Bai Qiang , Xiao Hailian , Liu Manhong , Sui Ning
Published: June 2020

MnSiO3 nanoparticles (NPs) were prepared by precipitation method, their structure and composition were characterised by transmission electron microscopy, electron diffraction spectroscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy. Due to the oxidase‐like enzyme activity of MnSiO3, it can catalyse the substrate 3,3′,5,5′‐tetramethylbenzidine (TMB) in acidic environment to form an oxidised TMB which has an absorption peak at 652 nm in the absence of hydrogen peroxide. When Fe2+ was added to the assay, the oxidase‐like activity of MnSiO3 was inhibited, and the intensity of the absorption at 652 nm was reduced. Based on the high oxidase‐like activity, a colorimetric method for Fe2+ detection was established, it showed high selectivity and sensitivity. In the optimised conditions, the limit of detection was 0.5 μM with a linear range from 3 to 63 μM. Moreover, the method was applied to determine Fe2+ in spiked water samples which gave satisfactory recoveries.
Growth characteristics of tin sulphides crystals by the vapour transport method using SnS and sulphur powders: effect of temperature and pressure
Authors: Kim Chaeeun , Park Jun‐Cheol , Ahn Ji‐Hoon
Published: June 2020

Tin sulphide compounds have two different types of 2D layered crystal structures with different electrical conduction types. Tin disulphide with n‐type semiconductor characteristics has a 2D crystal structure with hexagonal symmetry, while tin monosulphide (SnS) with p‐type semiconductor characteristics has a 2D crystal structure with orthorhombic symmetry. These layered materials have many potential applications such as electronic and optoelectronic devices. Meanwhile, it is known that the growth products of tin sulphides are very sensitive to the process parameters. In this study, the authors investigated the growth phenomena of tin sulphides by the vapour transport method using SnS and sulphur powders because vapour transport reactions are relatively simple and facilitate the understanding of the effects of growth parameters. The growth behaviour of tin sulphides as a function of process temperature and pressure was observed, and the results can be explained in terms of the sulphurisation and reduction of SnS powder during the growth process.
Electrochemical synthesis of silver nanoparticles in solutions of rhamnolipid
Authors: Kuntyi Orest , Mazur Artur , Kytsya Andriy , Karpenko Olena , Bazylyak Liliya , Mertsalo Ivanna , Pokynbroda Tetiana , Prokopalo Alla
Published: June 2020

The electrochemical method of synthesis of silver nanoparticles (AgNPs) using ‘sacrificial’ silver anode as a source of Ag+, microbial origin surfactant (rhamnolipid, RL) as a stabiliser of AgNPs and electric current as a reducer is presented. Using of cyclic voltammetry it was determined that RL concentration and temperature are the main factors influencing the rate of anodic dissolution of silver and cathodic reduction of the formed complex [AgRL]+. Increasing of RL concentration leads to increasing of the cathodic currents that indicate the increase of the rate of AgNPs formation. With increasing the temperature from 40 to 60°C the values of the anode and cathodic currents increase to 1.5 times, this indicates the predominant diffusion nature of the influence of the temperature on the synthesis of AgNPs. Obtained AgNPs were investigated using transmission electron microscopy and it was found that increasing of concentration of surfactant leads to decreasing of the size of AgNPs, whereas increasing of temperature, on the contrary, leads to increasing of mean size of AgNPs. Synthesised AgNPs showed significant antimicrobial activity against the bacterial phytopathogens Xanthomonas campestris and Agrobacterium tumefaciens. It has been shown that AgNPs stabilised by RL are characterised by low phytotoxicity.
Recurrent low-level luminosity behaviour after a giant outburst in the Be/X-ray transient 4U 0115+63
Authors: Rouco Escorial A. , Wijnands R. , van den Eijnden J. , Patruno A. , Degenaar N. , Parikh A. , Ootes L. S.
Published: June 2020

In 2017, the Be/X-ray transient 4U 0115+63 exhibited a new type II outburst that was two times fainter than its 2015 giant outburst (in the Swift/BAT count rates). Despite this difference between the two bright events, the source displayed similar X-ray behaviour after these periods. Once the outbursts ceased, the source did not transit towards quiescence directly, but was detected about a factor of 10 above its known quiescent level. It eventually decayed back to quiescence over timescales of months. In this paper, we present the results of our Swift monitoring campaign, and an XMM-Newton observation of 4U 0115+63 during the decay of the 2017 type II outburst and its subsequent low-luminosity behaviour. We discuss the possible origin of the decaying source emission at this low-level luminosity, which has now been shown as a recurrent phenomenon, in the framework of the two proposed scenarios to explain this faint state: cooling from an accretion-heated neutron star crust or continuous low-level accretion. In addition, we compare the outcome of our study with the results we obtained from the 2015/2016 monitoring campaign on this source.
Asteroseismic sensitivity to internal rotation along the red-giant branch
Authors: Ahlborn F. , Bellinger E. P. , Hekker S. , Basu S. , Angelou G. C.
Published: June 2020

Context. Transport of angular momentum in stellar interiors is currently not well understood. Asteroseismology can provide us with estimates of internal rotation of stars and thereby advances our understanding of angular momentum transport.

Aims. We can measure core-rotation rates in red-giant stars and we can place upper bounds on surface-rotation rates using measurements of dipole (l = 1) modes. Here, we aim to determine the theoretical sensitivity of modes of different spherical degree towards the surface rotation. Additionally, we aim to identify modes that can potentially add sensitivity at intermediate radii.

Methods. We used asteroseismic rotational inversions to probe the internal stellar rotation profiles in red-giant models from the base of the red-giant branch up to the luminosity bump. We used the inversion method of multiplicative optimally localised averages to assess how well internal and surface rotation rates can be recovered from different mode sets and different synthetic rotation profiles.

Results. We confirm that dipole mixed modes are sufficient to set constraints on the average core-rotation rates in red giants. However, surface-rotation rates estimated with only dipole mixed modes are contaminated by the core rotation. We show that the sensitivity to surface rotation decreases from the base of the red-giant branch until it reaches a minimum at 60–80% of the bump luminosity due to a glitch in the buoyancy frequency. Thereafter, a narrow range of increased surface sensitivity just below the bump luminosity exists. Quadrupole and octopole modes have more sensitivity in the outer parts of the star. To obtain accurate estimates of rotation rates at intermediate radii (i.e. a fractional radius of ∼0.4), acoustic oscillation modes with a spherical degree of l ≈ 10 are needed.

Conclusions. We find a minimum and subsequent maximum in the sensitivity to the surface rotation rate in red giants below the luminosity bump. Furthermore, we show that, if observed, quadrupole and octopole modes enable us to distinguish between differential and solid body rotation in the convection zone. This will be important when investigating the transport of angular momentum between the core and the envelope.
Masses of double neutron star mergers
Authors: Kruckow Matthias U.
Published: June 2020

Aims. I aim to explain the mass discrepancy between the observed double neutron-star binary population by radio pulsar observations and gravitational-wave observation.

Methods. I performed binary population synthesis calculations and compared their results with the radio and the gravitational-wave observations simultaneously.

Results. Simulations of binary evolution were used to link different observations of double neutron star binaries with each other. I investigated the progenitor of GW190425 in more detail. A distribution of masses and merger times of the possible progenitors is presented.

Conclusions. A mass discrepancy between the radio pulsars in the Milky Way with another neutron star companion and the inferred masses from gravitational-wave observations of those kind of merging systems is naturally found in binary evolution.
A unified accretion-ejection paradigm for black hole X-ray binaries
Authors: Marcel G. , Cangemi F. , Rodriguez J. , Neilsen J. , Ferreira J. , Petrucci P.-O. , Malzac J. , Barnier S. , Clavel M.
Published: June 2020

Context. We proposed in paper I that the spectral evolution of transient X-ray binaries (XrB) is due to an interplay between two flows: a standard accretion disk (SAD) in the outer parts and a jet-emitting disk (JED) in the inner parts. We showed in papers II, III, and IV that the spectral evolution in X-ray and radio during the 2010–2011 outburst of GX 339-4 can be recovered. However, the observed variability in X-ray was never addressed in this framework.

Aims. We investigate the presence of low frequency quasi-periodic oscillations (LFQPOs) during an X-ray outburst, and address the possible correlation between the frequencies of these LFQPOs and the transition radius between the two flows, rJ.

Methods. We select X-ray and radio data that correspond to 3 outbursts of GX 339-4. We use the method detailed in Paper IV to obtain the best parameters rJ(t) and ṁin(t) for each outburst. We also independently search for X-ray QPOs in each selected spectra and compare the QPO frequency to the Kepler and epicyclic frequencies of the flow in rJ.

Results. We successfully reproduce the correlated evolution of the X-ray spectra and the radio emission for 3 different activity cycles of GX 339-4. We use a unique normalisation factor for the radio emission, f∼R. We also report the detection of 7 new LFQPOs (3 Type B, and 4 Type C), to go along with the ones previously reported in the literature. We show that the frequency of Type C QPOs can be linked to the dynamical JED-SAD transition radius rJ, rather than to the optically thin-thick transition radius in the disk. The scaling factor q such that νQPO ≃ νK(rJ)/q is q ≃ 70 − 130, a factor consistent during the 4 cycles, and similar to previous studies.

Conclusions. The JED-SAD hybrid disk configuration not only provides a successful paradigm allowing us to describe XrB cycles, but also matches the evolution of QPO frequencies. Type C QPOs provide an indirect way to probe the JED-SAD transition radius, where an undetermined process produces secular variability. The demonstrated relation between the transition radius links Type C QPOs to the transition between two different flows, effectively tying it to the inner magnetized structure, i.e., the jets. This direct connection between the jets’ (accretion-ejection) structure and the process responsible for Type C QPOs, if confirmed, could naturally explain their puzzling multi-wavelength behavior.
JoXSZ: Joint X-SZ fitting code for galaxy clusters
Authors: Castagna Fabio , Andreon Stefano
Published: June 2020

The thermal Sunyaev-Zeldovich (SZ) effect and the X-ray emission offer separate and highly complementary probes of the thermodynamics of the intracluster medium. We presentJoXSZ, the first publicly available code designed to jointly fit SZ and X-ray data coming from various instruments to derive the thermodynamic profiles of galaxy clusters.JoXSZfollows a fully Bayesian forward-modelling approach, accounts for the SZ calibration uncertainty, and for the X-ray background level systematic. It improves upon most current and not publicly available analyses because it adopts the correct Poisson-Gauss expression for the joint likelihood, makes full use of the information contained in the observations, even in the case of missing values within the datasets, has a more inclusive error budget, and adopts a consistent temperature in the various parts of the code, allowing for differences between X-ray and SZ gas-mass weighted temperatures when required by the user.JoXSZaccounts for beam smearing and data analysis transfer function, accounts for the temperature and metallicity dependencies of the SZ and X-ray conversion factors, adopts flexible parametrisation for the thermodynamic profiles, and on user request, allows either adopting or relaxing the assumption of hydrostatic equilibrium (HE). When HE holds,JoXSZuses a physical (positive) prior on the radial derivative of the enclosed mass and derives the mass profile and overdensity radiirΔ. For these reasons,JoXSZgoes beyond simple SZ and electron density fits. We illustrate the use ofJoXSZby combining Chandra and NIKA data of the high-redshift cluster CL J1226.9+3332. The code is written in Python, it is fully documented, and the users are free to customise their analysis in accordance with their needs and requirements.JoXSZis publicly available on GitHub.
A wide angle view of the Sagittarius dwarf spheroidal galaxy
Authors: Sbordone L. , Hansen C. J. , Monaco L. , Cristallo S. , Bonifacio P. , Caffau E. , Villanova S. , Amigo P.
Published: June 2020

We report on the discovery and chemical abundance analysis of the first CEMP-r/s star detected in the Sagittarius dwarf spheroidal galaxy (Sgr dSph) by means of UVES high-resolution spectra. The star, found in the outskirts of Sgr dSph, along the major axis of the main body, is a moderately metal-poor giant (Teff = 4753 K, log g = 1.75, [Fe/H] = −1.55) with [C/Fe] = 1.13, placing it in the so-called “high-carbon band”, and strong s-process and r-process enrichment ([Ba/Fe] = 1.4, [Eu/Fe] = 1.01). Abundances of 29 elements from C to Dy were obtained. The chemical pattern appears to be best fitted by a scenario where an r-process pollution event pre-enriched the material out of which the star was born as secondary in a binary system whose primary evolved through the AGB phase, providing C- and s-process enrichment.