bluuebunny/crossref_metadata_2025 huggingface dataset:
Scientific Validation: A Crucial and Unavoidable Prerequisite to the Acceptability of New Tests and Testing Strategies
Authors: Balls Michael
Published: August 2020

— The use of in vitro techniques in fundamental pharmacotoxicological research is widespread, but relatively little progress has been made in applying the knowledge and experience gained to regulatory toxicity testing. This is largely because specific tests of various kinds are required by national and international laws and regulations, before chemicals and products of many types can be manufactured, transported or marketed. These requirements have led to the publication of standardised test guidelines by various regulatory authorities. Although there is an increasing willingness to accept, in principle, the incorporation of non-animal tests and testing strategies into regulatory practice, their relevance and reliability must first be established in recognised validation studies, the outcomes of which must be assessed by independent groups of experts. The formal validation of alternative methods is not progressing satisfactorily. The reasons for this are discussed and some suggestions for improvements are made.
Gap Junctional Intercellular Communication and Modulators of Kinases and Phosphatases
Authors: Husøy Trine , Mikalsen Svein-Ole , Sanner Tore
Published: August 2020

— Seven phosphatase inhibitors were used to investigate the possible importance of phosphatases in the regulation of gap junctional intercellular communication (GJIC). Only the tyrosine phosphatase inhibitor, pervanadate, was found to inhibit GJIC and to alter the band pattern of connexin43 (Cx43) in Western blots. Only the unphosphorylated band of Cx43 was seen after alkaline phosphatase treatment of pervanadate-exposed cells. Application of a tyrosine-specific phosphatase and a phosphotyrosine antibody clearly indicated that pervanadate induced tyrosine phosphorylation in Cx43.
The Reducing Agent Dithiothreitol (DTT) Increases Expression of c-myc and c-fos Proto-oncogenes in Human Cells
Authors: Skouv Jan , Kryspin-Sørensen Ilona , Frandsen Henrik , Rasmussen Eva Selzer , Forchhammer Jes
Published: August 2020

— The objective of the present study was to assess the possible tumour promoting activity of the food mutagen 2-hydroxyamino-1-methyl-6-phenylimidazo[4,5- b]pyridine ( N-OH-PhIP), by studying its influence on the expression of three genes considered to be of relevance in the tumour promotion step. The genes were two proto-oncogenes, c- fos and c- myc, and the tumour suppressor gene, p53. We observed that the expression of the c- fos and c- myc genes was induced when human bladder epithelial cells were treated with a standard solution of N-OH-PhIP and dithiothreitol (DTT), previously shown to be genotoxic. However, when cells were treated with DTT alone, the expression of c- fos and c- myc was also transiently induced. We therefore conclude that DTT, and not N-OH-PhIP, induced oncogene expression. Induction of both c- fos and c- myc expression by a reducing agent, DTT, which is frequently used in in vitro toxicology studies, is a novel observation that suggests the need for a cautious interpretation of such studies.
Defence Mechanisms Protecting Glial Cell Cultures against the Toxicity of Lead
Authors: Grundt Inger K. , Rise Marvelyn , Nyland Harald
Published: August 2020

— Several defence mechanisms against the toxicity of triethyllead (TEL) in cultures of glial cells have been studied. In contrast to cultures of glioma C6 cells, primary cultures of glial cells generated a resistance to the toxicity of TEL, which increased with the age of the cultures.

When the time of exposure of glial cells was extended from 24 hours to 6 days and the cells were exposed to increasing doses of TEL, the activities of several metabolic enzymes were stimulated by concentrations of TEL over 10-7M. Among these were glucose-6-phosphate-dehydrogenase and acid phosphatase. On the other hand, lactate dehydrogenase activity was not significantly affected under these experimental conditions.

When the cultures were exposed to 10 8M TEL, the cellular calcium content increased and the potassium content fell. This indicates that the activation of metabolic enzymes is a response to early events in the toxic process, which include disturbances in calcium metabolism. When glial cells were incubated with lead and selenium simultaneously, the uptake of lead into the cells was reduced, and the cellular calcium content was increased by selenium.
Direct Determination of Glutathione Reductase in Cells Cultured in Microtitre Plates as a Biomarker for Oxidative Stress
Authors: García-Alfonso Concepción , Sanz Pilar , Repetto Guillermo , Repetto Manuel , López-Barea Juan
Published: August 2020

— A new method was developed for the direct determination of glutathione reductase (GOR) activity in Vero cells cultured in microtitre plates, avoiding cell-free extract preparation. The cells in each well were washed twice with phosphate-buffered saline, lysed with Triton X-100, and assayed in 0.1M potassium phosphate, pH 7.0. After subtracting oxidase activity, which increased with NADPH concentration, the net GOR activity was similar at different oxidised glutathione (GSSG) and NADPH concentrations, thus confirming enzyme saturation. The optimised GOR assay used 2.5mM GSSG and 0.12mM NADPH; 5mM EDTA was also added to prevent the enzyme from redox inactivation. The GOR activity was directly proportional to the number of cells per well for a wide range of cell densities, thus supporting the assay's validity for use with cultured cells.

The effects on GOR activity of three chemicals which induce oxidative stress, namely, paraquat, iron (II) chloride and iron (III) chloride, were examined to validate the assay under experimental conditions. The specific enzymatic activity increased to 357% of untreated control activity in 5mM paraquat-treated cells, and to 407% of control activity in cells exposed to 7.5mM iron (II) chloride. By contrast, activity decreased to 56% of control activity in cells exposed to 5mM iron (III) chloride. In conclusion, the changes in GOR activity detected in Vero cells confirm that the new assay is suitable for routine in vitro screening of toxicants capable of inducing oxidative stress.
Inside out: The UK press, Brexit and strategic populist ventriloquism
Authors: Smith David , Deacon David , Downey John
Published: August 2020

This article examines how and when populist discourses were mobilised within the 2016 UK European Union (EU) Referendum campaign, by examining the specific temporal conjunctions between the changing strategy of the official ‘Vote Leave’ campaign, British national newspaper reporting of the Referendum and shifts in public opinion. Our analysis shows that Vote Leave only started to utilise anti-elitist and exclusionary populist rhetoric at the mid-point of the campaign, in response to constricting political opportunities, but by so doing transformed the dynamic of the Referendum. We term this an example of ‘strategic populist ventriloquism’, where elite politicians appropriate the language of insurgency for political advantage, and argue that current conceptual frameworks on media and populism need to be broadened to accommodate these occasions.
On infusing reachability-based safety assurance within planning frameworks for human–robot vehicle interactions
Authors: Leung Karen , Schmerling Edward , Zhang Mengxuan , Chen Mo , Talbot John , Gerdes J Christian , Pavone Marco
Published: August 2020

Action anticipation, intent prediction, and proactive behavior are all desirable characteristics for autonomous driving policies in interactive scenarios. Paramount, however, is ensuring safety on the road: a key challenge in doing so is accounting for uncertainty in human driver actions without unduly impacting planner performance. This article introduces a minimally interventional safety controller operating within an autonomous vehicle control stack with the role of ensuring collision-free interaction with an externally controlled (e.g., human-driven) counterpart while respecting static obstacles such as a road boundary wall. We leverage reachability analysis to construct a real-time (100 Hz) controller that serves the dual role of (i) tracking an input trajectory from a higher-level planning algorithm using model predictive control, and (ii) assuring safety by maintaining the availability of a collision-free escape maneuver as a persistent constraint regardless of whatever future actions the other car takes. A full-scale steer-by-wire platform is used to conduct traffic-weaving experiments wherein two cars, initially side-by-side, must swap lanes in a limited amount of time and distance, emulating cars merging onto/off of a highway. We demonstrate that, with our control stack, the autonomous vehicle is able to avoid collision even when the other car defies the planner’s expectations and takes dangerous actions, either carelessly or with the intent to collide, and otherwise deviates minimally from the planned trajectory to the extent required to maintain safety.
Giant sublingual hamartoma with medial cleft tongue: a case report and literature review
Authors: Li Juan , Mao Chi , Ma Lian , Zhou Xia
Published: August 2020

Hamartomas commonly occur in respiratory and digestive organs, such as the lungs, pancreas, and liver; they rarely occur in the oral cavity, especially in the sublingual region. This report describes a 5-month-old boy who presented with a giant sublingual hamartoma and medial cleft tongue. He underwent corrective operations at 5 months, 11 months, and 31 months of age. Histopathological analysis revealed features suggestive of hamartoma. There have been no signs of recurrence. The boy exhibited normal speech development at 3 years of age; all other oral functions were unaffected at that time. This report includes a review of relevant literature. The findings in this report and previous literature suggest that a multidisciplinary approach, carefully planned staged surgery, and rehabilitation are needed to achieve favorable outcomes in patients with hamartoma in the oral cavity.
Risk factors for surgical site infection after major oral oncological surgery: the experience of a tertiary referral hospital in China
Authors: Shi Menghan , Han Zhengxue , Qin Lizheng , Su Ming , Liu Yanbin , Li Man , Cheng Long , Huang Xin , Sun Zheng
Published: August 2020

Objective

To identify risk factors associated with surgical site infection (SSI) after major oral oncological surgery.

Methods

This retrospective study reviewed data from patients that underwent major surgery for oral cancer at a tertiary referral hospital in China between January 2005 and July 2016. SSI was diagnosed within 30 days. Demographic, cancer-related, preoperative, perioperative and postoperative data were analysed using descriptive statistics and univariate and multivariate analyses of the risk factors for SSI.

Results

A total of 786 patients were enrolled, of whom 125 had SSI (15.9%), which were all incisional. Independent risk factors for SSI, identified by multivariate analysis, were diabetes mellitus (odds ratio [OR] 2.147, 95% confidence interval [CI] 1.240, 3.642), prior radiotherapy (OR 4.595, 95% CI 1.293, 17.317) and oral–neck communication (OR 2.838, 95% CI 1.263, 7.604); and factors reflecting large extent resections were tracheostomy (OR 2.235, 95% CI 1.435, 3.525), anterolateral thigh flap (OR 1.971, 95% CI 1.103, 3.448) and latissimus dorsi flap (OR 4.178, 95% CI 1.325, 13.189).

Conclusions

Multiple risk factors were associated with SSI after major oral oncological surgery. To minimize SSI risk, surgeons managing oral cancer patients should have a better understanding of the risk factors, including diabetes mellitus, prior radiotherapy, tracheostomy, oral–neck communication and flap reconstruction.
Identification of differentially expressed genes between mucinous adenocarcinoma and other adenocarcinoma of colorectal cancer using bioinformatics analysis
Authors: Zhang Xue , Zuo Jing , Wang Long , Han Jing , Feng Li , Wang Yudong , Fan Zhisong
Published: August 2020

Objective

As a unique histological subtype of colorectal cancer (CRC), mucinous adenocarcinoma (MC) has a poor prognosis and responds poorly to treatment. Genes and markers related to MC have not been reported.

Methods

To identify biomarkers involved in development of MC compared with other common adenocarcinoma (AC) subtypes, four datasets were obtained from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were identified using GEO2R. A protein–protein interaction network was constructed. Functional annotation for DEGs was performed via DAVID, Metascape, and BiNGO. Significant modules and hub genes were identified using Cytoscape, and expression of hub genes and relationships between hub genes and MC were analyzed.

Results

The DEGs were mainly enriched in negative regulation of cell proliferation, bicarbonate transport, response to peptide hormone, cell–cell signaling, cell proliferation, and positive regulation of the canonical Wnt signaling pathway. The Venn diagram revealed eight significant hub genes: CXCL9, IDO1, MET, SNAI2, and ZEB2 were highly expressed in MC compared with AC, whereas AREG, TWIST1, and ZEB1 were expressed at a low level. AREG and MET might be significant biomarkers for MC.

Conclusion

The identified DEGs might help elucidate the pathogenesis of MC, identify potential targets, and improve treatment for CRC.
The regulatory role of exosomes in leukemia and their clinical significance
Authors: Deng Wei , Wang Li , Pan Ming , Zheng Jianping
Published: August 2020

Recurrence is a primary cause of death in patients with leukemia. The interactions of tumor cells with the microenvironment and tumor stem cells hidden in bone marrow promote the recurrence and metastasis of leukemia to lymphoid tissue. Exosomes, membrane-coated nanovesicles secreted by living cells, perform biomaterial transfer and information exchange between cells. Exosomes contain various other biological components derived from parental cells, and they remotely regulate the function of target cells through body fluid flow. Recent studies revealed that exosomes participate in the development of leukemia and play important roles in its diagnosis and treatment by influencing cell proliferation and apoptosis, regulating bone marrow microenvironment, promoting angiogenesis, and inhibiting hematopoiesis. Exosomes are potential biomarkers and therapeutic targets for leukemia, and they can influence drug resistance. Leukemia-derived exosomes present leukemia-related antigens to target cells, promote the proliferation of leukemic cells, help these cells escape immunity, protect them from the cytotoxic effects of chemotherapeutics, and promote angiogenesis and tumor migration. Therefore, exosomes are closely related to the metastasis, treatment, and prognosis of leukemia, and they can be used to detect and monitor the progression of leukemia. This paper reviews the regulatory roles of exosomes in leukemia and their clinical significance.
Perceived influence of mechanical engineering students’ work placement experiences on their occupational competency and self-efficacy
Authors: Ngonda Tiyamike , Shaw Corrinne , Kloot Bruce
Published: August 2020

This paper proposes a qualitative systems dynamics model that explains how students’ work placement experiences either enhance or hinder the growth of their occupational competency and self-efficacy. The model is developed from qualitative analysis of work placement experiences of mechanical engineering students from a South African university of technology. Findings from the analysis show that students’ occupational competency and self-efficacy could be considered emergent outcomes of interactions of the learning environment, mentor posture, mentor capacity, mentor availability, meaningfulness of work, scope of work, agency, doing work, co-participating, participation trajectory and performance trajectory. The explanation of the factors and social mechanisms that influence students’ occupational competency and self-efficacy that is offered by the qualitative systems dynamics model would enable the implementation of work placement programs in a manner that would promote rather than hinder the growth of these two indicators of student employability.
Prison-Based Interventions for Early Adults with Mental Health Needs: A Systematic Review
Authors: Givens Ashley , Moeller Kimberly , Johnson Terence L.
Published: August 2020

Rates of mental health needs of incarcerated young adults (15–35 year olds) are concerning, however, mental health interventions targeting this population are under studied. This article systematically reviews published, peer-reviewed research in nine databases pertaining to mental health interventions for incarcerated young adults. Only original studies conducted in the United States and determined to be valid though NIH assessment tools were included in this analysis. The review includes 19 original studies testing 14 intervention programs exploring mental health outcomes such as depression, PTSD, self-harm, and bipolar symptoms. Overall, findings were mixed about the impact of reviewed programs. The variety of interventions, outcomes, study settings, and implementation procedures complicates the ability to determine the impact of mental health programming in carceral settings. This review also reveals the lack of depth and replication of research in this area. Findings suggest additional efforts are needed to establish efficacy and best practices when treating mental health needs among this population.
Maximum power extraction framework using robust fractional-order feedback linearization control and GM-CPSO for PMSG-based WECS
Authors: Kahla Sami , Bechouat Mohcene , Amieur Toufik , Sedraoui Moussa , Babes Badreddine , Hamouda Noureddine
Published: August 2020

The most important issue in the use of wind energy conversion systems is to ensure maximum power extraction in terms of efficiency. Therefore, maximum power point tracking algorithms are as important as the maximum power point tracking controller. In this study, maximum power extraction frameworks operating the state-of-the-art optimization methods are presented for permanent magnet synchronous generator–based wind energy conversion system. These frameworks consist of a Gauss map–based chaotic particle swarm optimization and a hybrid maximum power point tracking approach that combines feedback linearization technique with fractional-order calculus. The feedback linearization control strategy can fully decouple and linearize the original state variables of the nonlinear system and thus provide an optimal controller crossing wide-range operating conditions. The objective is to maintain the tip speed ratio at its optimal value, which implies the use of a rotational speed loop. The method is based on the feedback linearization technique and the fractional control theory. Gauss map–based chaotic particle swarm optimization, which is a remarkable and recent optimization technique, is utilized to achieve optimum coefficients to efficiently ensure the maximum power point tracking operation in here. A simulation study is carried out on a 3-kW wind energy conversion system to show the effectiveness of the proposed control scheme.
Role of Aggregate Gradation in Balancing the Performance of Asphalt Concrete Mixtures
Authors: Vieira Denis , Garcia Victor M. , Abdallah Imad , Nazarian Soheil
Published: August 2020

Improving the durability and long-term performance of asphalt concrete (AC) has become a major concern, especially with the increase in the use of recycled materials, warm mix asphalt additives and modified binders. This paper presents an evaluation of different mix design approaches to balance the mechanical properties of AC mixtures. The current volumetric-based design method was enhanced with a performance-based analysis methodology that specifies the parameters from the overlay tester, Hamburg wheel tracking device and indirect tension tests. Two typical Superpave mixes from different plants that exhibited a poor performance, especially in cracking, were selected for this evaluation. The mixtures were first designed following the current volumetric-based design process and characterized under the proposed performance-based analysis. Two alternative approaches that consider the influence of the asphalt content and the aggregate gradation were explored to improve the engineering behavior of the mixtures. From this evaluation, two mixtures that could potentially yield optimal volumetric and balanced mechanical properties were developed. The optimization of the aggregate gradation is a promising approach to formulate a mixture with a balanced stability and durability, as judged by its rutting and cracking potentials.
Integrating Smartphone-Controlled Paper Airplane Into Gamified Science Inquiry for Junior High School Students
Authors: Cheng Mengmeng , Su Chien-Yuan , Kinshuk
Published: August 2020

Integrating science learning with game experience and physical manipulatives not only overcomes the rigidity of traditional teaching, but also makes the learning experience pleasant for students and improves their science inquiry ability. Today, with the popularization of mobile devices and technology, both the value and feasibility of gamified science learning have increased significantly. However, several studies showed that students might get lost or feel bored during science inquiry. To let students enjoy the science inquiry process and improve their science process skills, the researchers combined mobile technology, game design elements, and science inquiry and designed the gamified science inquiry activity “we are aircraft designers”. Here, students designed and manipulated a smartphone-controlled paper airplane by mobile devices connected via Bluetooth. To investigate the effects of the gamified science inquiry activity, the flow state and science process skills of 71 students of a junior high school in China were explored. The proposed gamified science inquiry activity enhanced flow and science process skills of students with high and middle level flow. No differences were found on flow and science process skills between males and females. Based on these results, the guidelines for the design of a gamified science inquiry activity are discussed.
Treatment of Postural Orthostatic Tachycardia Syndrome With Medication: A Systematic Review
Authors: Hasan Bashar , Almasri Jehad , Marwa Bilal , Klaas Kelsey M. , Fischer Philip R.
Published: August 2020

Purpose:

Postural orthostatic tachycardia syndrome has been recognized for decades, but treatment is largely based on anecdotal experience and expert opinion. Pharmacologic treatment is inconsistent and unstandardized. We did a systematic review to identify controlled studies from which informed treatment decisions can be made.

Method:

Through a standard systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we identified all English-language studies of a medication treatment for postural orthostatic tachycardia syndrome that included a comparison or control group and followed outcomes for at least 1 week of treatment.

Results:

A total of 626 studies were identified by the search criteria, and 8, involving a total of 499 patients, met the criteria. No studies were adequately similar to allow for meta-analysis. Of the identified 8 studies, 2 were randomized controlled trials and 4 had been subjected to peer review. In individual studies, there was some favorable effect with fludrocortisone, beta blockers, midodrine, and selective serotonin reuptake inhibitors.

Conclusion:

There is a paucity of high-quality data about effectiveness of medication in the treatment of postural orthostatic tachycardia syndrome. Nonetheless, 2 randomized trials and 6 other reports show some favorable effects of medication.
Investigation of the Shedding of Selected Respiratory Pathogens in Healthy Horses Presented for Routine Dental Care
Authors: Pusterla Nicola , Rice Molly , Henry Travis , Barnum Samantha , James Kaitlyn
Published: August 2020

The main objective of the study was to determine the frequency of detection of selected infectious respiratory viruses and bacteria in healthy horses presented over a 12-month period for routine dental care at 2 veterinary hospitals. Nasal secretions were collected from 579 horses and tested for equine herpesviruses (EHV-1, EHV-2, EHV-4, EHV-5), equine influenza virus (EIV), equine rhinitis A and B viruses (ERAV, ERBV), Streptococcus equi subspecies equi ( S equi), S equi subspecies zooepidemicus ( S zooepidemicus), and methicillin-resistant Staphylococcus aureus (MRSA) using routine diagnostic quantitative polymerase chain reaction assays. True respiratory pathogens (EHV-1, EHV-4, EIV, ERBV, and MRSA) were detected in 129 (22%) of the horses. Commensal respiratory pathogens (EHV-2, EHV-5, and S zooepidemicus) were detected in 515 (89%) of the study horses. ERAV and S equi were not detected in any of the study horses. The horses showed statistical differences between the 2 veterinary hospitals in regard to breed, age, presence of nasal discharge, rectal temperature, and detection of true and commensal respiratory pathogens. The data generated from the present study supports the risk for the transmission of true and commensal respiratory pathogens from subclinical shedders to susceptible horses. Equine veterinarians performing routine dental care should engage in routine biosecurity practices, with the goal to reduce disease spread.
Effects of temperature and loads on hardness and surface failure modes of cemented carbide
Authors: Wang Ben , Hao Tianxu , Yang Quanwei , Wang Minghai , Zheng Yaohui
Published: August 2020

Cemented carbide is a common cutting material with a hardness that significantly affects its usability. A Vickers indentation test was performed to analyse changes in the hardness of cemented carbide cutters with temperature and loads to understand its variation law. Moreover, indentation-induced surface damage was observed, and its elements were analysed. Crack distributions on the indentation surface were detected and analysed through an etching method. The results demonstrate that the hardness of cemented carbide decreases with greater temperatures and loads. At room temperature, the hardness of cemented carbide decreased from 1321 to 996 MPa when the loads increased from 300 to 800 N. When the external load was fixed at 500 N, the hardness of the cemented carbide decreased from 1113 to 939 MPa as the temperature increased from 25 to 350 °C. Moreover, the density of the indentation-induced surface damages increased with a reduction of the Vickers hardness. In addition, the mean free path of the binding phase for the cemented carbide with large grain sizes was relatively high. Therefore, it is difficult to generate diagonal cracks under large loads and high temperatures, which are beneficial to prevent cutter flaking.
Comparative study of two types of control loops aiming at trajectory tracking of a steer-by-wire system with Coulomb friction
Authors: Huang Chao , Li Liang , Wang Xiangyu
Published: August 2020

In an era of automated driving, steer-by-wire system seems to be an indispensable component for an autonomous vehicle. Among the many problems concerned, steering control of the system may be arguably the most indispensable part that lay the foundation for the system and is essentially a position servo control problem. Traditionally, the most commonly used control loop structures of the position servo system can be classified into two categories, both considering the current control loop as an essential part. However, this is not necessarily true in practical applications. In view of this, control systems with two different types of control loops based on proportional–integral–derivative controllers have been designed and compared in this paper for trajectory tracking of the steer-by-wire system with Coulomb friction. The aim is to explore the essential differences between the two types of control loops and study the effect of current loop on performance of the system. When properly designed, it can be seen that the asymptotic stability of the control system can be guaranteed. However, the system with type I control loop has a faster response speed, whereas the system with type II control loop has a smoother response. Theoretical as well as simulation and experimental results have been provided in detail, which can contribute to the understanding of the two types of control loops and can be used as guidance not only for researchers but also for engineering practice.
Optimization method of switch jumper setting based on strategies for reducing conductive interference in railway
Authors: Liu Chang , Yang Shiwu , Cui Yong , Lv Jiaqi , Chen Bingjun
Published: August 2020

Traction current can to impose conductive interference on the railway signalling system, which is also known as unbalanced traction current interference. In the station turnout section, the traction current may cause obvious interference on both receiving apparatus of track circuit and cab signalling apparatus due to the installation of multi-jumpers, wing rails, and insulated joints inside the turnout. This paper analyzes the above structural characteristics of turnouts in depth. By establishing a comprehensive simulation model of one-transmitter and two-receiver track circuit in turnout section and simulating the complete return current path along with traction network–locomotive–rails, the mechanism of traction current conductive interference in the turnout section is then illustrated, using Multisim and MATLAB/Simulink simulation platform. Finally, based on the Analytic Hierarchy Process (AHP), an optimization method of switch jumper setting is studied. The simulation results show that the conductive interference in the turnout section mainly involves two factors: The inherent turnout structure definitely results in different impedance of two rails, and the inductive cab signal is partly bypassed in the turnout center (nose rail). Especially, conductive interference magnitude depends on the jumper location. Therefore, in engineering practice, it is feasible to reduce the interference to a certain degree by reasonable settings of the switch jumper.
Investigation on the flow-control strategy for an aggressive turbine transition ducts
Authors: Liu Jun , Liu Hongrui , Liu Guang , Du Qiang , Wang Pei , Chang Sheng
Published: August 2020

After being studied for years, aggressive intermediate turbine duct is being attempted to be applied in turbine design to further improve the engine-performance. With such design, the shaft could be shortened effectively. However, under the influence of the more distorted coming-flow and stronger pressure-gradient in a real engine, the flow field would be more complicated definitely. Besides that, the upstream-rotor tip-leakage flow is a key loss-source by inducing separation. Flow-control strategies are necessary in this situation. In this paper, the flow field in an aggressive duct has been analyzed to declare the source of separation primarily. Then wide-chord blade design concept has been adopted as a control strategy firstly to realize the purpose of improving the areo-performance. After being verified, numerical method has been used in this study. Under the same aero-condition, the prototype and the modified turbine are analyzed. With this novel flow-control strategy, separation has been improved, even diminished. However, the flow structures within the blade passage are altered correspondingly. An instrumental conclusion is that the pressure loss could be decreased successfully by designing the wide-chord blade specially.
Real-time fault diagnosis using deep fusion of features extracted by parallel long short-term memory with peephole and convolutional neural network
Authors: Zhou Funa , Zhang Zhiqiang , Chen Danmin
Published: August 2020

Analysis of one-dimensional vibration signals is the most common method used for safety analysis and health monitoring of rotary machines. How to effectively extract features involved in one-dimensional sequence data is crucial for the accuracy of real-time fault diagnosis. This article aims to develop more effective means of extracting useful features potentially involved in one-dimensional vibration signals. First, an improved parallel long short-term memory called parallel long short-term memory with peephole is designed by adding a peephole connection before each forget gate to prevent useless information transferring in the cell. It can not only solve the memory bottleneck problem of traditional long short-term memory for long sequence but also can make full use of all possible information helpful for feature extraction. Second, a fusion network with new training mechanism is designed to fuse features extracted from parallel long short-term memory with peephole and convolutional neural network, respectively. The fusion network can incorporate two-dimensional screenshot image into comprehensive feature extraction. It can provide more accurate fault diagnosis result since two-dimensional screenshot image is another form of expression for one-dimensional vibration sequence involving additional trend and locality information. Finally, real-time two-dimensional screenshot image is fed into convolutional neural network to secure a real-time online diagnosis which is the primary requirement of the engineers in health monitoring. Validity of the proposed method is verified by fault diagnosis for rolling bearing and gearbox.
Guaranteed cost consensus for second-order multi-agent networks with time-varying delays and cost constraints
Authors: Yin Xinli , Wang Zhong , Yang Bailong , Yang Kunyu
Published: August 2020

This article investigates the current guaranteed cost consensus control for multi-agent networks with time-varying delays and cost constraints. First, a guaranteed cost consensus control protocol with a linear quadratic function is proposed to make a tradeoff decision between the consensus regulation performance and control cost consumption. Then, for the case without a cost constraint, the main theorem provides sufficient conditions to reach the leader-following guaranteed cost consensus with switching transmission topologies, where the time-varying delay term is handled using the derivative form. The upper bound for the linear quadratic function is calculated; it is related to the time-varying delays and the initial conditions. Moreover, guaranteed cost consensus analysis criteria are developed for the case including a cost constraint. The correlation between the cost constraint condition and an explicit guaranteed cost upper bound is constructed, and the matrix dimension is independent of the number of agents. Finally, the obtained theoretical results are verified through numerical simulations.
Synthesis of N,N′-bis(1,5-dimethyl-2-phenyl-1,2-dihydro-3-oxopyrazol-4-yl) sebacamide that ameliorate osteoarthritis symptoms and improve bone marrow matrix structure and cartilage alterations induced by monoiodoacetate in the rat model: “Suggested potent anti-inflammatory agent against COVID-19”
Authors: Refat MS , Hamza RZ , Adam AMA , Saad HA , Gobouri AA , Al-Salmi FA , Altalhi T , El-Megharbel SM
Published: August 2020

To assess the chondroprotective effect and influence of N, N′-bis(1,5-dimethyl-2-phenyl-1,2-dihydro-3-oxopyrazol-4-yl) sebacamide (dpdo) that was synthesized through the reaction of phenazone with sebacoyl chloride and screened for its biological activity especially as anti-arthritic and anti-inflammatory agent in a monoiodoacetate (MA)-induced experimental osteoarthritis (OA) model. Thirty male albino rats weighing “190–200 g” were divided randomly into three groups (10 each): control, MA-induced OA, and MA-induced OA + dpdo. In MA-induced OA rat, the tumor necrosis factor alpha, interleukin 6, C-reactive protein, rheumatoid factors, reactive oxygen species, as well as all the mitochondrial markers such as mitochondria membrane potential, swelling mitochondria, cytochrome c oxidase (complex IV), and serum oxidative/antioxidant status (malondialdehyde level and activities of myeloperoxidase and xanthine oxidase) are elevated. Also, the activity of succinate dehydrogenase (complex II), levels of ATP, the level of glutathione (GSH), and thiol were markedly diminished in the MA-induced OA group compared to the normal control rats. These findings showed that mitochondrial function is associated with OA pathophysiological alterations and high gene expressions of (IL-6, TNF-a, and IL-1b) and suggests a promising use of dpdo as potential ameliorative agents in the animal model of OA and could act as anti-inflammatory agent in case of severe infection with COVID-19. It is clearly appeared in improving the bone cortex and bone marrow in the treated group with the novel compound in histological and transmission electron microscopic sections which is a very important issue today in fighting severe infections that have significant effects on the blood indices and declining of blood corpuscles like COVID-19, in addition to declining the genotoxicity and inflammation induced by MA in male rats. The novel synthesized compound was highly effective in improving all the above mentioned parameters.
Vinpocetine attenuates thioacetamide-induced liver fibrosis in rats
Authors: Elnfarawy Ahmed A , Nashy Asmaa E , Abozaid Alaa M , Komber Ibrahim F , Elweshahy Rawan H , Abdelrahman Rehab S
Published: August 2020

Liver fibrosis is associated with increased mortality and morbidity. However, there is not effective treatment so far. Vinpocetine (Vinpo) is a synthetic derivative of vinca alkaloid vincamine. Limited previous reports have shown some beneficial effects of Vinpo in different organ fibrosis, but the ability of Vinpo to inhibit liver fibrosis induced by thioacetamide (TAA) has not been reported, that is why we investigate the potential ability of this vinca alkaloid derivative to attenuate liver fibrosis. Hepatic fibrosis was induced in male Sprague Dawley rats by TAA (200 mg/kg; ip; 3 times/week) for 6 weeks. Daily treatments with Vinpo (10–20 mg/kg/day; orally) ameliorated TAA-induced hepatic oxidative stress and histopathological damage as indicated by a decrease in liver injury markers, LDH, hepatic MDA, and NOx levels, as well as increase anti-oxidative parameters. Besides, the anti-fibrotic efficacy of Vinpo was confirmed by decreasing hydroxyproline, and α-SMA. Also, the anti-inflammatory effect of Vinpo was explored by decreasing IL-6 and TNF-α levels. Our novel findings were that Vinpo decreased VEGF/Ki-67 expression in the liver confirming its effect on angiogenesis and proliferation. These findings reveal the anti-fibrotic effect of Vinpo against TAA-induced liver fibrosis in rats, and suggest the modulation of oxidative stress, inflammation, angiogenesis and proliferation as mechanistic cassette underlines this effect.
Laboratory-confirmed bloodstream infection in systemic lupus erythematosus: Risk profiling and short-term mortality
Authors: Wang Man , Zhang Huijuan , Yang Xiaopei , Li Wei , Li Tianfang , Liu Shengyun
Published: August 2020

Objectives

To delineate laboratory-confirmed bloodstream infection (LCBI), analyze risk factors for its occurrence and predictors for its short-term mortality in systemic lupus erythematosus (SLE) patients. Methods A single center, retrospective, case-controlled study was performed in 159 SLE patients (2013–2019) to identify risk factors of LCBI by comparing patients with LCBI (n = 39) to those without infection (n = 120). The predictors associated with 30-day mortality in LCBI patients were also analyzed.

Results

Altogether 40 bacteria strains were isolated in 39 LCBI patients with a predominance of the gram-negative bacilli (24 strains, 60.0%). Escherichia coli and Staphylococcus aureus were the leading Gram-negative and Gram-positive microorganisms, respectively. Occurrence of LCBI was independently predicted by: SLE disease duration >4 years, SLEDAI score >4 points, glucocorticoids dose >7.5 mg/d and the previous or concomitant occurrence of autoimmune hemolytic anemia (AIHA) or thrombotic microangiopathy (TMA). Based on the identified risk factors, we developed a matrix model for the risk of future LCBI. The 30-day mortality (39 cases) was 23.1% and healthcare-associated LCBI was a predictor for 30-day mortality in SLE patients compared with community-acquired LCBI.

Conclusion

Longer duration, higher disease activity and glucocorticoids dose, and occurrence of AIHA or TMA were risk factors of LCBI in SLE and its poor short-term prognosis may attribute to healthcare-associated LCBI.
The risk of hospitalized infection in patients with systemic lupus erythematosus treated with hydroxychloroquine
Authors: Sakai Ryoko , Honda Suguru , Tanaka Eiichi , Majima Masako , Konda Naoko , Takada Hideto , Harigai Masayoshi
Published: August 2020

Objective

To compare the risk of hospitalized infection (HI) between users and non-users of hydroxychloroquine (HCQ) in systemic lupus erythematosus (SLE).

Methods

Using claims data, patients were defined as SLE cases by the following criteria: 1) they had at least one SLE diagnostic code; 2) they had a prescription for specific drugs, including corticosteroids, steroid pulse therapy, and immunosuppressive drugs; and 3) they were at least 16 years old between September 2015 and July 2017 (n = 17,483). The SLE cases with at least one prescription for HCQ were defined as the HCQ group (n = 1,431), while the others were defined as the non-HCQ group. Among the SLE cases, propensity score-matched cases were observed for 1 year (n = 1,095 in each group).

Results

The median age and proportion of female patients in both groups were about 42 years and 88%, respectively. The proportions of cases with HIs were similar (HCQ group, 4.5%; non-HCQ group, 5.6%; p = 0.240, McNemar test). The hazard ratio of the HCQ group for HIs after adjusting for patients’ characteristics was not significant at 0.9 (0.6–1.3).

Conclusion

The use of HCQ was not associated with a risk of HIs in patients with SLE.
Trends in mortality from lupus in Spain from 1980 to 2018
Authors: Hernández-Rodríguez Juan Carlos , Durán-Romero Antonio Jose , Muñoz-Jiménez Alejandro , Conejo-Mir Julian , Pereyra-Rodríguez Jose Juan
Published: August 2020

Background

Recent studies suggest that Systemic lupus erythematosus (SLE) mortality rates in Spain are decreasing. However, SLE mortality in Spain has been poorly studied. The purpose of study is to assess the temporal trends of mortality rates in the Spanish population with SLE from 1980 to 2018.

Methods

Death records and mid-year population data were collected from the National Statistics Institute. Age-standardized mortality rates were calculated for overall population and for each sex and age group. Significant changes in mortality trends were identified by Joinpoint regressions. Also, an Age-period-cohort (APC) and Potential Years of Life Lost (PYLL) analysis was carried out to know the burden of SLE disease.

Results

The overall SLE mortality rates in Spain has experimented an increased through the last 39 years. Mortality rates from the period 1980–1984 was 0.83 per 1.000.000 inhabitants, reaching the value to 1.77 cases per 1.000.000 from the period 2014–2018. A decreasing trend has been observed since 1999.

Conclusions

SLE mortality rate has increased in Spain between 1980 and 1999, with a sustained decrease up to our days.
Human Amniotic Membrane Enriched with Urinary Bladder Fibroblasts Promote the Re-Epithelization of Urothelial Injury
Authors: Jerman Urška Dragin , Veranič Peter , Cirman Tina , Kreft Mateja Erdani
Published: August 2020

Culturing cells in three-dimensional systems that include extracellular matrix components and different cell types mimic the native tissue and as such provide much more representative results than conventional two-dimensional cell cultures. In order to develop biomimetic bladder tissue in vitro, we used human amniotic membrane (AM) extracellular matrix as a scaffold for bladder fibroblasts (BFs) and urothelial cells. Our aims were to evaluate the integration of BFs into the AM stroma, to assess the differentiation of the urothelium on BFs-enriched AM scaffolds, and to evaluate the AM as a urothelial wound dressing. First, to achieve the optimal integration of BFs into AM stroma, different intact and de- epithelialized AM (dAM) scaffolds were tested. BFs secreted matrix metalloproteinase (MMP)-1 and MMP-2 and integrated into the stroma of all types of AM scaffolds. Second, to establish urothelial tissue equivalent, urothelial cells were seeded on dAM scaffolds enriched with BFs. The BFs in the stroma of the AM scaffolds promoted (1) the proliferation of urothelial cells, (2) the attachment of urothelial cells on AM basal lamina with hemidesmosomes, and (3) development of multilayered urothelium with expressed uroplakins and well-developed cell junctions. Third, we established an ex vivo model of the injured bladder to evaluate the dAM as a wound dressing for urothelial full-thickness injury. dAM acted as a promising wound dressing since it enabled rapid re-epithelization of urothelial injury and integrated into the bladder tissue. Herein, the developed urothelial tissue equivalents enable further mechanistic studies of bladder epithelial–mesenchymal interactions, and they could be applied as biomimetic models for preclinical testing of newly developed drugs. Moreover, we could hypothesize that AM may be suitable as a dressing of the wound that occurs during transurethral resection of bladder tumor, since it could diminish the possibility of tumor recurrence, by promoting the rapid re-epithelization of the urothelium.
Neonatal Pig Sertoli Cells Survive Xenotransplantation by Creating an Immune Modulatory Environment Involving CD4 and CD8 Regulatory T Cells
Authors: Kaur Gurvinder , Wright Kandis , Mital Payal , Hibler Taylor , Miranda Jonathan M. , Thompson Lea Ann , Halley Katelyn , Dufour Jannette M.
Published: August 2020

The acute cell-mediated immune response presents a significant barrier to xenotransplantation. Immune-privileged Sertoli cells (SC) can prolong the survival of co-transplanted cells including xenogeneic islets, hepatocytes, and neurons by protecting them from immune rejection. Additionally, SC survive as allo- and xenografts without the use of any immunosuppressive drugs suggesting elucidating the survival mechanism(s) of SC could be used to improve survival of xenografts. In this study, the survival and immune response generated toward neonatal pig SC (NPSC) or neonatal pig islets (NPI), nonimmune-privileged controls, was compared after xenotransplantation into naïve Lewis rats without immune suppression. The NPSC survived throughout the study, while NPI were rejected within 9 days. Analysis of the grafts revealed that macrophages and T cells were the main immune cells infiltrating the NPSC and NPI grafts. Further characterization of the T cells within the grafts indicated that the NPSC grafts contained significantly more cluster of differentiation 4 (CD4) and cluster of differentiation 8 (CD8) regulatory T cells (Tregs) at early time points than the NPI grafts. Additionally, the presence of increased amounts of interleukin 10 (IL-10) and transforming growth factor (TGF) β and decreased levels of tumor necrosis factor (TNF) α and apoptosis in the NPSC grafts compared to NPI grafts suggests the presence of regulatory immune cells in the NPSC grafts. The NPSC expressed several immunoregulatory factors such as TGFβ, thrombospondin-1 (THBS1), indoleamine-pyrrole 2,3-dioxygenase, and galectin-1, which could promote the recruitment of these regulatory immune cells to the NPSC grafts. In contrast, NPI grafts had fewer Tregs and increased apoptosis and inflammation (increased TNFα, decreased IL-10 and TGFβ) suggestive of cytotoxic immune cells that contribute to their early rejection. Collectively, our data suggest that a regulatory graft environment with regulatory immune cells including CD4 and CD8 Tregs in NPSC grafts could be attributed to the prolonged survival of the NPSC xenografts.