bluuebunny/crossref_metadata_2025 huggingface dataset:
A CT‐Based Radiomics Approach for the Differential Diagnosis of Sarcomatoid and Clear Cell Renal Cell Carcinoma
Authors: Meng Xiaoli , Shu Jun , Xia Yuwei , Yang Ruwu
Published: July 2020

This study was aimed at building a computed tomography‐ (CT‐) based radiomics approach for the differentiation of sarcomatoid renal cell carcinoma (SRCC) and clear cell renal cell carcinoma (CCRCC). It involved 29 SRCC and 99 CCRCC patient cases, and to each case, 1029 features were collected from each of the corticomedullary phase (CMP) and nephrographic phase (NP) image. Then, features were selected by using the least absolute shrinkage and selection operator regression method and the selected features of the two phases were explored to build three radiomics approaches for SRCC and CCRCC classification. Meanwhile, subjective CT findings were filtered by univariate analysis to construct a radiomics model and further selected by Akaike information criterion for integrating with the selected image features to build the fifth model. Finally, the radiomics models utilized the multivariate logistic regression method for classification and the performance was assessed with receiver operating characteristic curve (ROC) and DeLong test. The radiomics models based on the CMP, the NP, the CMP and NP, the subjective findings, and the combined features achieved the AUC (area under the curve) value of 0.772, 0.938, 0.966, 0.792, and 0.974, respectively. Significant difference was found in AUC values between each of the CMP radiomics model (0.0001 ≤ p ≤ 0.0051) and the subjective findings model (0.0006 ≤ p ≤ 0.0079) and each of the NP radiomics model, the CMP and NP radiomics model, and the combined model. Sarcomatoid change is a common pathway of dedifferentiation likely occurring in all subtypes of renal cell carcinoma, and the CT‐based radiomics approaches in this study show the potential for SRCC from CCRCC differentiation.
Associated Targets of the Antioxidant Cardioprotection of Ganoderma lucidum in Diabetic Cardiomyopathy by Using Open Targets Platform: A Systematic Review
Authors: Shaher Fahmi , Qiu Hongbin , Wang Shuqiu , Hu Yu , Wang Weiqun , Zhang Yu , Wei Yao , AL-ward Hisham , Abdulghani Mahfoudh A. M. , Alenezi Sattam Khulaif , Baldi Salem , Zhou Shaobo
Published: July 2020

Even with substantial advances in cardiovascular therapy, the morbidity and mortality rates of diabetic cardiomyopathy (DCM) continually increase. Hence, a feasible therapeutic approach is urgently needed. Objectives. This work is aimed at systemically reviewing literature and addressing cell targets in DCM through the possible cardioprotection of G. lucidum through its antioxidant effects by using the Open Targets Platform (OTP) website. Methods. The OTP website version of 19.11 was accessed in December 2019 to identify the studies in DCM involving G. lucidum. Results. Among the 157 cell targets associated with DCM, the mammalian target of rapamycin (mTOR) was shared by all evidence, drug, and text mining data with 0.08 score association. mTOR also had the highest score association 0.1 with autophagy in DCM. Among the 1731 studies of indexed PubMed articles on G. lucidum published between 1985 and 2019, 33 addressed the antioxidant effects of G. lucidum and its molecular signal pathways involving oxidative stress and therefore were included in the current work. Conclusion. mTOR is one of the targets by DCM and can be inhibited by the antioxidative properties of G. lucidum directly via scavenging radicals and indirectly via modulating mTOR signal pathways such as Wnt signaling pathway, Erk1/2 signaling, and NF‐κB pathways.
Convergence of Antiperiodic Boundary Value Problems for First-Order Integro-Differential Equations
Authors: Wang Yameng , Zhang Juan , Sun Yufeng
Published: July 2020

In this paper, we investigate the convergence of approximate solutions for a class of first-order integro-differential equations with antiperiodic boundary value conditions. By introducing the definitions of the coupled lower and upper solutions which are different from the former ones and establishing some new comparison principles, the results of the existence and uniqueness of solutions of the problem are given. Finally, we obtain the uniform and rapid convergence of the iterative sequences of approximate solutions via the coupled lower and upper solutions and quasilinearization method. In addition, an example is given to illustrate the feasibility of the method.
The Effect of Coffee on Pharmacokinetic Properties of Drugs : A Review
Authors: Belayneh Anteneh , Molla Fantahun
Published: July 2020

Background. Coffee has been the most commercialized food product and most widely consumed stimulant beverage in the world. It is a major source of caffeine which is the most bioactive component of coffee. Although both the United States Department of Agriculture and European Food Safety Authority consider daily intake of coffee which contains 400 mg of caffeine as safe for health, it causes different clinically significant pharmacokinetic interactions with many drugs. The aim of this work was to review the effect of coffee on the pharmacokinetic properties of drugs.Method. This review was done by investigating the in vitro and in vivo research findings, clinical case reports, and expert panels from credible sources including Scopus, PubMed, Hindawi, OVID, Google Scholar, Embase, Cochrane Library, and Web of Science. Result. Several studies and medical case reports evidently showed that concomitant consumption of coffee significantly affects the absorption, distribution, metabolism, and excretion of many drugs. These effects of coffee on the pharmacokinetics of drugs could lead to enhanced therapeutic response, therapeutic failure, or toxic reactions. Conclusion and Recommendation. Concomitant use of coffee should be avoided with medications which have a significant interaction with coffee. There should be an appropriate time gap between intake of drugs and coffee based on drug properties. Pharmacists and clinicians should be aware of the potential risks of drug‐coffee interaction and advice patients appropriately. Further in vitro and in vivo studies should be done for frequently prescribed drugs to get a strong evidence on the pharmacokinetic interaction with coffee.
Influence of Bioadditives Made from Sugarcane Bagasse on Interpenetrating Polymer Networks
Authors: Liu Kuan-Liang , Kuo Pei-Yu , Han Jin-Lin , Hsieh Kuo-Huang
Published: July 2020

To achieve a sustainable bioeconomy, various bioderived additives have been developed to produce biocomposites, but only a handful of research on biocomposites focuses on the effect of bioderived additives on interpenetrating polymer networks (IPNs). This study is aimed at understanding the interaction between bioadditives and interpenetrating polymer networks and is the first study to build the relationship between bioadditive ratio and damping factor based on dynamic mechanical analysis. The IPNs were prepolymerized in bulk by isocyanate and poly(oxypropylene) polyol (PPG) with two different molecular weights (PPG 700 and PPG 1000), and then, they were grafted with bisphenol A diglycidyl ether epoxy. The bioadditives were prepared from agricultural waste, sugarcane bagasse, and the effect of the coupling agent 3-glycidoxypropyltrimethoxysilane on a bioadditive surface was also discussed in this study. The results show that modified bioadditives have significant enhancement on tensile strength and tensile modulus of polyurethane-grafted epoxy resin interpenetrating polymer networks (PU(PPG)-EP graft-IPNs). However, the enhancement is not from a strong covalent bond between matrix and additives, that is, due to the well-dispersed bioadditives which provide stiff segments. The static and dynamic mechanical performance, water absorption ratio, and morphology of the (PU(PPG)-EP graft-IPNs) elastomers were also thoroughly discussed in this study.
Sitagliptin Mitigates Total Body Irradiation-Induced Hematopoietic Injury in Mice
Authors: Wang Meifang , Dong Yinping , Wu Jing , Li Hongyan , Zhang Junling , Lu Lu , Zhang Yuanyang , Zhou Zewei , Fan Saijun , Li Deguan , Meng Aimin
Published: July 2020

Sitagliptin, an inhibitor of the dipeptidyl peptidase IV (DPP4), has been implicated in the regulation of type 2 diabetes. However, the role and mechanism of sitagliptin administration in total body irradiation (TBI)- induced hematopoietic cells injury are unclear. In this study, we demonstrated that sitagliptin had therapeutic effects on hematopoietic damage, which protected mice from 7.5 Gy TBI-induced death, increased the numbers and colony formation ability of hematopoietic cells. These therapeutic effects might be attributed to the inhibition of NOX4-mediated oxidative stress in hematopoietic cells, and the alleviation of inflammation was also helpful. Therefore, sitagliptin has potential as an effective radiotherapeutic agent for ameliorating TBI-induced hematopoietic injury.
Shenmayizhi Formula Combined with Ginkgo Extract Tablets for the Treatment of Vascular Dementia: A Randomized, Double‐Blind, Controlled Trial
Authors: Zhang Huiqin , Cao Yu , Pei Hui , Wang Huichan , Ma Lina , Wang Zhiyong , Diao Xuemei , Yang Yang , Liu Nanyang , Wei Yun , Li Hao
Published: July 2020

Shenmayizhi formula (SMYZF) has been shown to have an effect on vascular dementia (VaD) in previous studies. The aim of this study was to evaluate whether a combination of SMYZF with Ginkgo extract tablets improves mild‐to‐moderate VaD. In this 12‐week, randomized, double‐blind, controlled study, we randomly assigned 196 patients with VaD (aged 50–85 years) to either the SMYZF group (n = 98) or the Ginkgo group (n = 98). All patients received Ginkgo extract tablets as a basic treatment, while the SMYZF group also received SMYZF treatment. We evaluated the participants at baseline and after 12 weeks of the intervention for the following: the Mini‐Mental State Examination (MMSE), National Institutes of Health Stroke Scale (NIHSS), activities of daily living (ADL), Chinese Medicine Symptom Scale (CM‐SS) scores, serum endothelin‐1 (ET‐1), nitric oxide (NO), vascular endothelial growth factor (VEGF), von Willebrand factor (vWF), neuron‐specific enolase (NSE), brain‐derived neurotrophic factor (BDNF), and homocysteine (Hcy) serum levels. Both interventions significantly increased MMSE scores and decreased NIHSS, ADL, and CM‐SS scores. The SMYZF group showed greater improvement in MMSE, NIHSS, and CM‐SS scores. Both groups showed a significant decrease in serum ET‐1 and an increase in serum VEGF. Furthermore, serum NO increased, and vWF decreased significantly in the SMYZF group. Changes in serum ET‐1 and NO were greater in the SMYZF group. Both groups showed a significant increase in serum BDNF and a decrease in serum NSE and Hcy. Improvement in serum NSE and BDNF was greater in the SMYZF group. SMYZF combined with Ginkgo extract tablets improved vascular endothelial and cognitive functions, as well as the syndromes diagnosed based on the traditional Chinese medicine in patients with VaD.
Crack Detection of Reinforced Concrete Member Using Rayleigh‐Based Distributed Optic Fiber Strain Sensing System
Authors: Liu Tingjin , Huang Honghao , Yang Yubing
Published: July 2020

Early detection of crack is critical for the maintenance of reinforced concrete (RC) structures. In this study, a distributed optical fiber (DOF) sensing system with Rayleigh Optical Frequency Domain Reflectometry (OFDR) technique was deployed to a member of RC structure in a full‐scale laboratory experiment, which was subjected to a monotonic lateral load. With the aid of a high space resolution (up to 1 mm) and measurement accuracy (±1 micro strain) interrogator (OSI‐S by Semicon), continuous strain measurements inside of the RC member are elaborately implemented. The result of crack detection by the analysis of the measured tensile strain profiles is in excellent agreement with the visually observable cracks mapped during the test. This confirms the ability of the optical fiber inside of RC members to capture cracks on concrete surface. Moreover, the recognition of crack orientation and depth is accomplished by comparing strain measurements of optical fibers installed at multiple locations.
The Effect of Lithium on Inflammation-Associated Genes in Lipopolysaccharide-Activated Raw 264.7 Macrophages
Authors: Makola Raymond T. , Mbazima Vusi G. , Mokgotho Matlou P. , Gallicchio Vincent S. , Matsebatlela Thabe M.
Published: July 2020

Lithium remains the preferred Food and Drug Administration- (FDA-) approved psychiatric drug for treatment of bipolar disorders since its medical establishment more than half a century ago. Recent studies revealed a promising role for lithium in the regulation of inflammation, oxidative stress, and neurodegeneration albeit unclear about its exact mode of action. Thus, the intention of this study is to delineate the regulatory mechanisms of lithium on oxidative stress in lipopolysaccharide- (LPS-) activated macrophages by evaluating its effects on nuclear factor-κB (NF-κB) activity and mRNA expression of multiple oxidative stress-related NF-κB genes. Raw 264.7 macrophages were treated with up to 10 mM lithium, and no change in cell proliferation, viability, growth, and cell adhesion was observed in real time. Pretreatment with low doses of lithium was shown to reduce nitric oxide (NO) production in LPS-activated macrophages. A reduced internal H2DCFDA fluorescence intensity, indicative of reduced reactive oxygen species (ROS) production, was observed in LPS-activated Raw 264.7 macrophages treated with lithium. Lithium has been shown to lower the production of the chemokine RANTES; furthermore, this inhibitory action of lithium has been suggested to be independent of glycogen synthase kinase-3 β (GSK3β) activity. It is shown here that lithium modulates the expression of several inflammatory genes including IκB-α, TRAF3, Tollip, and NF-κB1/p50 which are regulators of the NF-κB pathway. Moreover, lithium inhibits NF-κB activity by lowering nuclear translocation of NF-κB in LPS-activated macrophages. This is the first study to associate Tollip, Traf-3, and IκB-α mRNA expression with lithium effect on NF-κB activity in LPS-activated Raw 264.7 macrophages. Although these effects were obtained using extratherapeutic concentrations of lithium, results of this study provide useful information towards understanding the mode of action of lithium. This study associates lithium with reduced oxidative stress in LPS-activated Raw 264.7 macrophages and further suggests candidate molecular targets for the regulation of oxidative stress-related diseases using lithium beyond bipolar disorders.
Designing High-Freedom Responsive Feeder Transit System with Multitype Vehicles
Authors: Wang Zhengwu , Yu Jie , Hao Wei , Chen Tao , Wang Yi
Published: July 2020

The last mile travelling problem is the most challenging part when using public transit. This study designs a high-freedom responsive feeder transit (HFRFT) system to serve at the transfer station, given vehicle routes, departure time, and service area based on demand. The proposed feeder transit system employs a travelling mode with multitype vehicles. In order to improve the operation of the HFRFT system, the optimization design methods are suggested for vehicle routes, scheduling, and service area. A mixed integer programming model and its hybrid of a metaheuristic algorithm are proposed to efficiently and integrally solve the vehicle routes and scheduling parameters according to the reservation requirements. A heuristic method is proposed to optimize the service area based on the equilibrium of system supply and demand. Case studies show that the mixed running mode of multiple models can significantly improve the seat utilization, which can also significantly reduce the number of departures and the average travel distance per passenger. The proposed service area optimization method is proved to be feasible to improve the last mile travel.
A Three-Step Iterative Method for Solving Absolute Value Equations
Authors: Feng Jing-Mei , Liu San-Yang
Published: July 2020

In this paper, we transform the problem of solving the absolute value equations (AVEs)Ax−x=bwith singular values ofAgreater than 1 into the problem of finding the root of the system of nonlinear equation and propose a three-step algorithm for solving the system of nonlinear equation. The proposed method has the global linear convergence and the local quadratic convergence. Numerical examples show that this algorithm has high accuracy and fast convergence speed for solving the system of nonlinear equations.
Mechanical Characteristics and Failure Characteristics of Jointed Rock under Axial Unloading and Radial Unloading
Authors: Han Tielin , Shi Junping , Chen Yunsheng
Published: July 2020

In this research, we used precracked rock‐like materials (simulating jointed rock masses) to assess the triaxial compression of cracked specimens under axial unloading and radial unloading paths. The research goal was to comparatively analyze and research the mechanical characteristics of cracked specimens to ascertain how deformation properties, strength properties, and failure features influence the overall mechanisms in context. The test results showed that the failure of specimens did not appear at peak stress under axial unloading and radial unloading. The elastic stage, yield stage, and failure stage of the stress‐strain curves were not clearly defined in the testing process. However, the stress drop and the strain of resilience of the lateral strain‐axial strain curve happened under this path because the lateral strain was significantly greater than the axial strain. This in turn led the volumetric strain to remain in a state of expansion throughout the testing process. The mechanical properties under this path are mainly influenced by the crack inclination angle, the unloading speed of radial pressure, and the initial confining pressure. However, there is a difference in the influence of these three factors on their mechanical parameters; that is, the influence of the crack inclination angle is the greatest, followed by that of the initial confining pressure, while that of the unloading speed of radial pressure is relatively small. Finally, the failure characteristics of specimens often present mixed tension‐shear failure under axial unloading and radial unloading.
Semantic Integration of Sensor Knowledge on Artificial Internet of Things
Authors: Huang Yikun , Xue Xingsi , Jiang Chao
Published: July 2020

Artificial Internet of Things (AIoT) integrates Artificial Intelligence (AI) with the Internet of Things (IoT) to create the sensor network that can communicate and process data. To implement the communications and co-operations among intelligent systems on AIoT, it is necessary to annotate sensor data with the semantic meanings to overcome heterogeneity problem among different sensors, which requires the utilization of sensor ontology. Sensor ontology formally models the knowledge on AIoT by defining the concepts, the properties describing a concept, and the relationships between two concepts. Due to human’s subjectivity, a concept in different sensor ontologies could be defined with different terminologies and contexts, yielding the ontology heterogeneity problem. Thus, before using these ontologies, it is necessary to integrate their knowledge by finding the correspondences between their concepts, i.e., the so-called ontology matching. In this work, a novel sensor ontology matching framework is proposed, which aggregates three kinds of Concept Similarity Measures (CSMs) and an alignment extraction approach to determine the sensor ontology alignment. To ensure the quality of the alignments, we further propose a compact Particle Swarm Optimization algorithm (cPSO) to optimize the aggregating weights for the CSMs and a threshold for filtering the alignment. The experiment utilizes the Ontology Alignment Evaluation Initiative (OAEI)’s conference track and two pairs of real sensor ontologies to test cPSO’s performance. The experimental results show that the quality of the alignments obtained by cPSO statistically outperforms other state-of-the-art sensor ontology matching techniques.
Association of the Expression Level of miR-16 with Prognosis of Solid Cancer Patients: A Meta-Analysis and Bioinformatic Analysis
Authors: Zhang Wanting , Zhou Feixiang , Jiang Danjie , Mao Yingying , Ye Ding
Published: July 2020

Objective. To assess the association between the expression level of miR-16 and prognosis of solid cancer patients by meta-analysis and bioinformatic analysis. Methods. PubMed, Web of Science, and Embase databases were searched until October 31, 2019, to identify eligible studies reporting the association of the miR-16 status with the prognosis of solid cancer patients. Hazard ratios (HRs) with 95% confidence intervals (CIs) were pooled, and a heterogeneity test was conducted. Sensitivity analysis and a publication bias test were also carried out. Furthermore, the miRpower database was used to validate the association. Results. Thirteen articles with 2303 solid cancer patients were included in the meta-analysis. Solid cancer patients with low expression level of miR-16 had shorter survival time (I2=84.0%, HR=1.47, 95% CI: 1.13-1.91, P=0.004). In the subgroup analyses of cancer sites, low miR-16 expression level was associated with poor prognosis in the reproductive system cancers (I2=33.3%, HR=1.24, 95% CI: 1.06-1.45, P=0.008). Sensitivity analysis suggested that the pooled HR was stable and omitting a single study did not change the significance of the pooled HR. Begg’s test and Egger’s test revealed no publication bias in the meta-analysis. In bioinformatic analysis, the significant association between miR-16 level and prognosis of patients with reproductive system cancers was further confirmed (HR=1.21, 95% CI: 1.03-1.42, P=0.017). Conclusion. Low expression level of miR-16 is an indicator for poor prognosis of solid cancer patients, particularly in reproductive system cancers.
Condition Monitoring of Chain Sprocket Drive System Based on IoT Device and Convolutional Neural Network
Authors: Lee Sang Kwon , Back Jiseon , An Kanghyun , Kim Sunwon , Lee Changho , Kim Pungil
Published: July 2020

This paper proposes a condition monitoring method for the early defect detection in a chain sprocket drive (CSD) system and classification of fault types before a catastrophic failure occurs. In the operation of a CSD system, early defect detection is very useful in preventing system failure. In this work, eight fault types associated with the CSD system components, such as the gear tooth, bearings, and drive motor shaft, were arbitrarily damaged and incorporated into the CSD system. To detect the fault signals during the CSD system operation, the vibration was measured using an Internet of Things (IoT) device, which features a wireless MEMS accelerometer, Bluetooth function, Wi-Fi function, and battery. The IoT device was mounted on the gearbox housing. The measured one-dimensional vibration time-series was transformed into time-scale images using continuous wavelet transform (CWT). A convolution neural network (CNN) was employed to extract deep features embedded in the images, which are closely related to fault types. To update the learning parameters of the CNN, the RMSprop learning algorithm was applied, and the CNN was trained using 500 image samples. Multiple-classification performance of the trained network was tested using 100 image samples. Feature maps for different fault types were obtained from the final CNN convolution layer. For the visualization of fault types, t-stochastic neighbor embedding was employed and applied to the feature maps to convert high-dimensional data into two-dimensional data. Two-dimensional features enabled excellent classification of the eight fault types and one normal type.
Noninteractive Lightweight Privacy-Preserving Auditing on Images in Mobile Crowdsourcing Networks
Authors: Zhang Juan , Wan Changsheng , Zhang Chunyu , Guo Xiaojun , Chen Yongyong
Published: July 2020

To determine whether images on the crowdsourcing server meet the mobile user’s requirement, an auditing protocol is desired to check these images. However, before paying for images, the mobile user typically cannot download them for checking. Moreover, since mobiles are usually low-power devices and the crowdsourcing server has to handle a large number of mobile users, the auditing protocol should be lightweight. To address the above security and efficiency issues, we propose a novel noninteractive lightweight privacy-preserving auditing protocol on images in mobile crowdsourcing networks, called NLPAS. Since NLPAS allows the mobile user to check images on the crowdsourcing server without downloading them, the newly designed protocol can provide privacy protection for these images. At the same time, NLPAS uses the binary convolutional neural network for extracting features from images and designs a novel privacy-preserving Hamming distance computation algorithm for determining whether these images on the crowdsourcing server meet the mobile user’s requirement. Since these two techniques are both lightweight, NLPAS can audit images on the crowdsourcing server in a privacy-preserving manner while still enjoying high efficiency. Experimental results show that NLPAS is feasible for real-world applications.
Exploring the Occurrence of Clogging in Highly Permeable Coarse Soils of Dam Foundations
Authors: Ma Jianquan , Peng Hao , Li Shibo , Duan Zhao , Zhang Xinshe , Ma Donghe
Published: July 2020

Leakage through the permeable coarse soils of dam foundations in Tibet, China, lessened over time without any additional antiseepage measures. In fact, clogging generated during the infiltration process is recognized as the major factor in reducing leakage. A laboratory study was conducted to understand clogging in highly permeable coarse soil of a dam foundation with the primary aim of determining the clogging patterns and optimum clogging particle size (PS). Seven replicate experiments were constructed using soil media with PS ranges of 32–64 mm, 16–32 mm, 8–16 mm, 4–8 mm, 2–4 mm, 1‐2 mm, and 0.5–1 mm to observe clogging after feeding the soil media with sediments of different PSs. The experimental results showed that four clogging patterns were formed in different PSs of the coarse foundation soil. The ratio of the effective aperture of the soil Dea and the equivalent clogging particle size de(de/Dea) had a dominant effect on the four clogging patterns (surface clogging, (de/Dea) > 1; surface‐internal clogging, 0.5 < (de/Dea) ≤ 1; internal partial pore blockage, 0.25 < (de/Dea) ≤ 0.5; and unclogging, (de/Dea) ≤ 0.25). The assessment criterion of the optimum clogging pattern was determined by 0.5 < (de/Dea) ≤ 1, and from that, the optimum clogging PS do was calculated.
Evaluating the Tourist Climate Comfortable Period of China in a Changing Climate
Authors: Yu Dan-Dan , Li Shan , Guo Zhong-Yang
Published: July 2020

The evaluation of climate comfort for tourism can provide information for tourists selecting destinations and tourism operators. Understanding how climate conditions for tourism evolve is increasingly important for strategic tourism planning, particularly in rapidly developing tourism markets like China in a changing climate. Multidimensional climate indices are needed to evaluate climate for tourism, and previous studies in China have used the much criticized “climate index” with low resolution climate data. This study uses the Holiday Climate Index (HCI) and daily data from 775 weather stations to examine interregional differences in the tourist climate comfortable period (TCCP) across China and summarizes the spatiotemporal evolution of TCCP from 1981 to 2010 in a changing climate. Overall, most areas in China have an “excellent” climate for tourism, such that tourists may visit anytime with many choices available. The TCCP in most regions shows an increasing trend, and China benefits more from positive effects of climate change in climatic conditions for tourism, especially in spring and autumn. These results can provide some scientific evidence for understanding human settlement environmental constructions and further contribute in improving local or regional resilience responding to global climate change.
Noise Reduction for Modal Parameter Identification of the Measured FRFs Using the Modal Peak-Based Hankel-SVD Method
Authors: Zhu Tianxu , Zang Chaoping , Zhang Gengbei
Published: July 2020

The measured frequency response functions (FRFs) in the modal test are usually contaminated with noise that significantly affects the modal parameter identification. In this paper, a modal peak-based Hankel-SVD (MPHSVD) method is proposed to eliminate the noise contaminated in the measured FRFs in order to improve the accuracy of the identification of modal parameters. This method is divided into four steps. Firstly, the measured FRF signal is transferred to the impulse response function (IRF), and the Hankel-SVD method that works better in the time domain rather than in the frequency domain is further applied for the decomposition of component signals. Secondly, the iteration of the component signal accumulation is conducted to select the component signals that cover the concerned modal features, but some component signals of the residue noise may also be selected. Thirdly, another iteration considering the narrow frequency bands near the modal peak frequencies is conducted to further eliminate the residue noise and get the noise-reduced FRF signal. Finally, the modal identification method is conducted on the noise-reduced FRF to extract the modal parameters. A simulation of the FRF of a flat plate artificially contaminated with the random Gaussian noise and the random harmonic noise is implemented to verify the proposed method. Afterwards, a modal test of a flat plate under the high-temperature condition was undertaken using scanning laser Doppler vibrometry (SLDV). The noise reduction and modal parameter identification were exploited to the measured FRFs. Results show that the reconstructed FRFs retained all of the modal features we concerned about after the noise elimination, and the modal parameters are precisely identified. It demonstrates the superiority and effectiveness of the approach.
Experimental Study of Pressure Pulsation in a Mixed-Flow Pump with Different Tip Clearances Based on Wavelet Analysis
Authors: Ji Leilei , Li Wei , Shi Weidong , Zhou Ling , Agarwal Ramesh
Published: July 2020

In order to investigate the effect of various impeller tip clearances on the pressure pulsation in a mixed-flow pump, the energy performance test and pressure pulsation experiment of a mixed-flow pump with different tip clearances are studied simultaneously. The pressure pulsation signals at impeller inlet, middle, and oulet are processed and analyzed by the wavelet transform. The results show that the change of tip clearance can affect the head and efficiency of mixed-flow pump. Under designed flow rate, when the tip clearance increases from 0.2 mm to 1.1 mm, the head and efficiency decrease by 18.1% and 11.6%, respectively. Due to the strong influence of blade passing frequency (BPF) at impeller middle, the period of pressure pulsation curve is about 1/4 of impeller rotation period. At impeller inlet, the low-frequency pulsation with energy concentration is the main disturbance frequency, and, with the increase of tip clearance, not only does the high-value region of wavelet spectrum expand to low-frequency direction but also it is easy to form second-order peaks in the time-averaged wavelet curve. At impeller outlet, affected by BPF and rotor-stator interaction (RSI), the high-frequency disturbance in RSI area decreases first and then increases. The wavelet coherence demonstrates the stable low-frequency disturbances in comparison to others and it will affect the flow field at impeller middle.
Affective and Psychotic Disorders in War-Torn Eastern Part of the Democratic Republic of the Congo: A Cross-Sectional Study
Authors: Vivalya Bives Mutume , Bin Kitoko Germain Manzekele , Nzanzu Adelard Kalima , Vagheni Martial Mumbere , Masuka Rock Kasereka , Mugizi Wilson , Ashaba Scholastic
Published: July 2020

Background. There is lack of information about prevalence of affective and psychotic disorders triggered by traumatic events among people living in war-affected regions. This study is aimed at determining the prevalence rate of affective and psychotic disorders and the associated factors in a war-torn eastern part of Democratic Republic of the Congo. Methods. This epidemiological cross-sectional descriptive study was carried out from 1st January 2019 to 31st December 2019 at Cepima and Muyisa health centers. This study enrolled 344 patients that had experienced traumatic events in Eastern Democratic Republic of the Congo from the 1119 participants, of whom 229 had positive bipolar affective disorder and 115 patients had psychotic disorders. Results. The results revealed that bipolar affective disorders were two times more than psychotic disorders. Sexual abuse, sudden death of a relative, kidnapping, the physical torture, and childhood trauma were the psychological factors correlated to the occurrence of bipolar affective and psychotic disorders. Conclusions. It was concluded that the traumatic experiences were precursors for the occurrence of bipolar affective and psychotic spectrum disorders.
Structured H∞ Control of an Electric Power Steering System
Authors: Zhou Hongbo , Pang Aiping , Yang Jing , He Zhen
Published: July 2020

Electric power steering (EPS) systems are prone to oscillations because of a very small phase angle margin, so a stable controller is required to increase the stability margin. In addition, the EPS system has parameter disturbances in the gain of the torque map under different conditions, which requires a certain degree of robustness in the control design. This paper synthesizes the multidimensional performance requirements considering the stability margin, robustness, and bandwidth of the system to form an H∞ optimization matrix with multidimensional performance output in using the structured H∞ control design. The structured H∞ controller not only retains the characteristics of traditional H∞ controllers with excellent robust performance and high stability margin but also has a lower order, which can be better applied in practice. Based on the performance requirements of the system and practical implementation, the structured H∞ controllers with different orders were designed, and the feasibility of the structured controller was confirmed through comparison and theoretical analysis.
Targeted Tumor Therapy with Radiolabeled DNA Intercalator: A Possibility? Preclinical Investigations with 177Lu‐Acridine
Authors: Ghosh Subhajit , Das Tapas , Suman Shishu K. , Kumar Chandan , Sarma Haladhar D. , Dash Ashutosh
Published: July 2020

Objective. A DNA intercalating agent reversibly stacks between the adjacent base pairs of DNA and thus is expected to exhibit preferential localization in the tumorous lesions as tumors are associated with enhanced DNA replication. Therefore, radiolabeled DNA intercalators are supposed to have potential to be used in targeted tumor therapy. Working in this direction, an attempt was made to radiolabel 9‐aminoacridine, a DNA intercalator, with 177Lu, one of the most useful therapeutic radionuclides, and study the potential of 177Lu‐acridine in targeted tumor therapy. Experiments. 9‐Aminoacridine was coupled with p‐NCS‐benzyl‐DOTA to facilitate radiolabeling, and the conjugate was radiolabeled with 177Lu. Different reaction parameters were optimized in order to obtain 177Lu‐acridine complex with maximum radiochemical purity. In vitro stability of the radiolabeled complex was studied in normal saline and human blood serum. Biological behavior of the radiolabeled agent was studied both in vitro and in vivo using the Raji cell line and fibrosarcoma tumor‐bearing Swiss mice, respectively. Results. 177Lu‐acridine complex was obtained with ~100% radiochemical purity under the optimized reaction conditions involving incubation of 1.5 mg/mL of ligand with 177Lu (1 mCi, 37 MBq) at 100°C at pH ~5 for 45 minutes. The complex maintained a radiochemical purity of >85% in saline at 6 d and >70% in human serum at 2 d postpreparation. In vitro cellular study showed uptake of the radiotracer (5.3 ± 0.13%) in the Raji cells along with significant cytotoxicity (78.06 ± 2.31% after 6 d). Biodistribution study revealed considerable accumulation of the radiotracer in tumor 9.98 ± 0.13 %ID/g within 1 h postadministration and retention therein till 6 d postadministration 4.00 ± 0.16 %ID/g with encouraging tumor to nontarget organ uptake ratios. Conclusions. The present study, although preliminary, indicates the potential of 177Lu‐acridine and thus radiolabeled DNA intercalators in targeted tumor therapy. However, further detailed evaluation is required to explore the actual potential of such agents in targeted tumor therapy.
Optimality Conditions for a Nonsmooth Uncertain Multiobjective Programming Problem
Authors: Han Wenyan , Yu Guolin , Gong Tiantian
Published: July 2020

This note is devoted to the investigation of optimality conditions for robust approximate quasi weak efficient solutions to a nonsmooth uncertain multiobjective programming problem (NUMP). Firstly, under the extended nonsmooth Mangasarian–Fromovitz constrained qualification assumption, the optimality necessary conditions of robust approximate quasi weak efficient solutions are given by using an alternative theorem. Secondly, a class of generalized convex functions is introduced to the problem (NUMP), which is called the pseudoquasi-type-I function, and its existence is illustrated by a concrete example. Finally, under the pseudopseudo-type-I generalized convexity hypothesis, the optimality sufficient conditions for robust approximate quasi weak efficient solutions to the problem (NUMP) are established.
The right man in the right place
Authors: Torrejais Ana
Published: July 2020

O desenvolvimento da indústria ferroviária brasileira na primeira metade do século XX deveu-se a uma conjunção de fatores, que seriam determinantes para a progressiva modernização tecnológica deste setor. Entre esses fatores, pretende-se analisar o impacto das estratégias de capacitação da força de trabalho, adotadas pelas companhias ferroviárias paulistas a partir de 1920 e em articulação com as normativas internacionais de gerência cientifica. Conforme se procurará demonstrar, a consolidação do ensino profissional no setor industrial ferroviário deveu-se, sobretudo, à atuação do engenheiro Roberto Mange, idealizador da Escola Profissional Mecânica do Liceu de Artes e Ofícios de São Paulo, posteriormente substituída pelo Centro Ferroviário de Ensino e Formação Profissional e finalmente continuado pelo Serviço Nacional de Aprendizagem Profissional, prevalecendo os fundamentos da organização racional do trabalho na metodologia de ensino veiculada por estas instituições.
As medicinas das Minas Gerais a partir de três manuais setecentistas
Authors: Viotti Ana Carolina De Carvalho
Published: July 2020

Este breve estudo trata de três manuais médicos escritos por cirurgiões licenciados nas Minas Gerais – o Erário Mineral (1736), a Relação cirúrgica e médica (1747) e o Governo de Mineiros [...] (1770). A partir deles, discutirei brevemente os limites da atuação desse tipo de profissional na colônia portuguesa nas Américas e a escritura de obras de cunho prescritivo por não-médicos, interrogando quais as doenças recorrentemente identificadas por eles, quais os tratamentos indicados, quais os referenciais médicos anunciados, que tipo de medicamento era comumente indicado e para quem esses remédios eram receitados. Percorrendo esse caminho, o objetivo é dar os principais contornos do que fora uma importante faceta da prática oficial de curar nas Minas Setecentistas
Estevão Cabral (1734-1811) contra Newton
Authors: Moura Breno Arsioli
Published: July 2020

Neste artigo, é analisado em detalhes o manuscrito “Reflexões breves sobre a natureza e propriedades da luz, ou sobre os dous sistemas da vibração, e da emanação Carteziano e Neutoniano”, escrito por Estevão Cabral (1734-1811), não publicado, e hoje guardado nos arquivos da biblioteca da Academia de Ciências de Lisboa, em Portugal. O manuscrito, sem data, traz uma forte crítica à concepção corpuscular para a luz – ou seja, a óptica newtoniana –, ao mesmo tempo em que destaca a superioridade da concepção vibracional. Uma vez que a literatura especializada geralmente aborda a recepção favorável a Newton em terras portuguesas, o manuscrito de Cabral parece ser uma notável exceção.
As possibilidades e tensões entre imaginação, ciência e tecnologia nas histórias da Futurian Society of New York
Authors: Seiffert Andreya Susane
Published: July 2020

Neste artigo, eu abordo a relação da ciência com as histórias de ficção científica produzidas por um grupo de escritores denominados The Futurians, que existiu de 1938 a 1945. Para tanto, eu discuto a noção de ciência presente nos Estados Unidos e como ela foi utilizada pela ficção científica. Relacionado a isso, abordo os “heróis” das histórias. Na terceira seção, eu falo sobre um personagem pouco discutido mas de grande influência, Charles Fort, e de como suas ideias espalharam-se pela ficção científica. Por fim, analiso como a ideia de ciência em crise de Thomas Kuhn pode ser usada para pensar a ciência das histórias de ficção científica, em especial aquelas que envolvem a mente e seus “poderes”, como a telepatia.
Indígenas brasileiros e o uso das plantas
Authors: Gaudêncio Jéssica Da Silva , Rodrigues Sérgio Paulo Jorge , Martins Décio Ruivo
Published: July 2020

Esse artigo sintetiza alguns exemplos de conhecimentos tradicionais apresentado pelos indígenas brasileiros ao longo da história em relação ao uso e manejo das plantas. O objetivo é destacar a relevância da etnociência indígena, levando em consideração que os indígenas foram grandes contribuidores da história da ciência no Brasil, em que indicam as diferentes formas de se considerar a natureza em que vivem, suas técnicas em variados contextos culturais, a inter-relação com diferentes formas do saber e suas transformações ao longo da história. Assim, este trabalho reúne informações sobre o uso das plantas presente na cultura indígena brasileira, numa abordagem sobre seus costumes, conhecimentos sobre ervas medicinais, corantes, o uso de venenos, desenvenenamento, dentre outras atividades, sob o ponto de vista etnocientífico, apoiados em registros de documentos históricos.
Carta de Berkeley sobre as erupções do monte Vesúvio
Authors: Conte Jaimir
Published: July 2020

Tradução de uma carta do filósofo George Berkeley, publicada originalmente no Philosophical Transactions, boletim oficial da Royal Society, de Londres, em outubro de 1717. No extrato da carta aqui traduzida sobre as erupções do Vesúvio Berkeley revela­-se um observador curioso e preciso. É notável, acima de tudo, a qualidade literária do seu texto, uma característica que seus trabalhos anteriores, especialmente os Três diálogos entre Hylas e Philonous, de 1713, já haviam revelado. Essa talvez seja uma das principais razões que fazem da carta um documento histórico-científico de permanente interesse.
A história da epistemologia no cinema
Authors: Temporão Anna Carolina Velozo Nader
Published: July 2020

O filme Contato, baseado no livro homônimo de Carl Sagan de 1995, expõe um interessante processo de mudança das crenças de sua protagonista ao longo da narrativa, cuja passagem do racionalismo dogmático ao ceticismo mitigado nos permite fazer uma ponte com a história da filosofia cética, sobretudo da idade moderna. O filme também nos mostra que ceticismo pode ser vivido, sendo um caminho que permite uma abertura maior para aceitação da multiplicidade de crenças e do pluralismo teórico existente no mundo.
Por uma ficção científica ou uma ciência ficcional
Authors: Albuquerque Alana Soares
Published: July 2020

Exploramos, neste artigo, a singularidade da prática científica em sua relação com a ficção, afirmando a existência de um aspecto ficcional que não só dá possibilidade à invenção das ciências, como está presente em qualquer gesto de produção de saber. Entendemos que a ficção científica, por sua vez, funciona investindo em tal aspecto especulativo que move a produção de teorias, porém voltando o método da especulação à própria ciência, já que se dedica a imaginar os possíveis desdobramentos do desenvolvimento tecnocientífico. Uma vez que tais especulações sobre o futuro têm predominado no imaginário ocidental, afirmamos que nesse gesto de criação de mundos possíveis está presente o que podemos chamar de uma cronopolítica, ou seja, um tipo de política que incide sobre o tempo.
15 anos da paleontologia molecular
Authors: Alves Everton Fernando
Published: July 2020

Comunicação sobre a descoberta de tecidos moles em fósseis, que permitem a controversa extração do DNA, e inauguraram o recente campo da paleontologia molecular.
Feasibility and Safety of Laparoscopic‐Guided Epicardial Access for Ventricular Tachycardia Ablation
Authors: Carmo Andre A. L. , Zenobio Silvia , Santos Bruno C. , Rocha Manoel O. C. , Ribeiro Antonio L. P.
Published: July 2020

Background

The usual approach to epicardial access in patients with Chagas cardiomyopathy and megacolon is surgical access to avoid bowel injury. However, there are concerns regarding its safety in cases of Chagas cardiomyopathy with reports of prolonged mechanical ventilation and high mortality in this clinical setting. The aim of this study was to examine feasibility and complication rates for ventricular tachycardia ablation performed with laparoscopic‐guided epicardial access.

Methods and Results

This single center study examined complication rates of the first 11 cases of ventricular tachycardia ablation in patients with Chagas cardiomyopathy, using laparoscopic guidance to access epicardial space. All 11 patients underwent epicardial VT ablation using laparoscopic‐guided epicardial access, and the complication rates were compared with historical medical reports. The main demographic features of our population were age, 63±13 years; men, 82%; and median ejection fraction, 31% (Q1=30% and Q3=46%). All patients were sent for ventricular tachycardia ablation because of medical therapy failure. The reason for laparoscopy was megacolon in 10 patients and massive liver enlargement in 1 patient. Epicardial access was achieved in all patients. Complications included 1 severe cardiogenic shock and 1 phrenic nerve paralysis. No intra‐abdominal organ injury occurred; only 1 death, which was caused by progressive heart failure, was reported more than 1 month after the procedure.

Conclusions

Laparoscopic‐guided epicardial access in the setting of ventricular tachycardia ablation and enlarged intra‐abdominal organ is a simple alternative to more complex surgical access and can be performed with low complication rates.