bluuebunny/crossref_metadata_2025 huggingface dataset:
ANALYSIS OF STUDENTS’ STEM LITERACY BASED ON GENDER DIFFERENCES IN SCIENCE LEARNING
Authors: Nurramadhani Annisa
Published: April 2020

STEM literacy can be defined as an ability to identify, apply, and to integrate the concept of science, technology, engineering, and mathematics to innovate and solve the complex problem. Especially in science learning that approached by the strategies like STEM. Because this revolution industry 4.0 era, students are demand to workface in integrate to their living life. So, they are asked can solved the problem properly, giving the solution for global problem wisely. In the process of learning science with project, somehow students show their own performance. The results of project-based learning pointing the different result of performing based on gender differences. The method that is used is descriptive. The subject in this research is the student’s preservice teacher of science and biology education study program for about 21 students with 4 boys and 17 girls in the second semester of the freshmen. The research is conducted in basic physic laboratory. The laboratory activity is using STEM approach with project. The students are divided into 4 groups and each group consist of boy’s students. The research instrument to take the data that is used are observation sheet for student’s performance in laboratory activity and questionnaire of students for their laboratory activity per-aspect that describes their competences in science, technology, engineering, and mathematics. The technique to take the data that is used in this research are video recording, observation, and informal interview. The results are student’s STEM literacy has different score based on the gender differences. In the first project, sailor boat, boys reach the higher percentages in aspect science, engineering, and technology, while girls reach the higher percentages in science and technology. The second project, let’s fun with music, boys reach the higher percentages in aspect science, engineering, and technology, while girls reach the higher percentages in science and engineering. In both of project, boys and girls reach the lowest percentages in mathematics aspect. But, in whole score boys has reached higher than girls.  It can be concluded that boys are outperformed than girls in STEM literacy in science learning especially in basic physics laboratory activity.
ANALISIS KETERAMPILAN DASAR MENGAJAR MAHASISWA PGSD
Authors: Sundari Fitri Siti , Muliyawati Yuli
Published: April 2020

Penelitian ini menggunakan metode kualitatif dengan desain deskriptif. Penelitian ini bertujuan untuk memperoleh gambaran apa adanya tentang bagaimana keterampilan mahasiswa PGSD yang sedang melaksanakan Program Pengalaman Lapangan di 5 (lima) sekolah dasar di Bogor. Data yang diperoleh dari penelitian ini merupakan hasil analisis dokumen, observasi, dan wawancara dengan guru, siswa, dan mahasiswa PGSD. Penelitian ini dilaksanakan di SDN Semeru I, SDN Polisi 4, SDN Semplak I, SDN Lawanggintung I, dan SDN Lawanggintung II Bogor. Jenis data yang digunakan dalam penelitian ini berbentuk narasi, uraian, penjelasan, dan penilaian dari informan baik lisan maupun tulisan yang dideskripsikan dalam bentuk catatan lapangan, angket, dan dokumentasi. Sumber data penelitian ini adalah mahasiswa PGSD yang sedang melaksanakan PPL di SDN Semeru I, SDN Polisi 4, SDN Semplak I, SDN Lawanggintung I, dan SDN Lawanggintung II Bogor. Informan dalam penelitian ini adalah dosen pembimbing PPL dan guru pamong di SDN Semeru I, SDN Polisi 4, SDN Semplak I, SDN Lawanggintung I, dan SDN Lawanggintung II Bogor. Hasil penelitian ini menunjukkan bahwa keterampilan menjelaskan sudah dikuasai dengan sangat baik. Sedangkan keterampilan bertanya, keterampilan membuka dan menutup pelajaran, keterampilan membimbing diskusi kelompok kecil, keterampilan mengajar kelompok kecil dan perseorangan, keterampilan mengelola kelas, dan keterampilan memberikan penguatan sudah memperoleh hasil yang baik. Keterampilan mengadakan variasi memperoleh hasil yang cukup baik.Kata Kunci : keterampilan bertanya, keterampilan menjelaskan, keterampilan membuka dan menutup pelajaran, keterampilan memberikan penguatan, keterampilan mengelola kelas, keterampilan membimbing diskusi kelompok kecil, keterampilan mengajar kelas kecil dan perorangan, keterampilan mengadakan variasi, mahasiswa PGSD.
EVALUASI PROGRAM PENDIDIKAN INKLUSI PADA SEKOLAH DASAR NEGERI BATU TULIS 2 KOTA BOGOR
Authors: Rianty Rianty , Jalal Fasli , Deniyanti Pinta , Elizabeth Patras Yuyun
Published: April 2020

ABSTRACTThis study evaluate the implementation of inclusive education program. The method use the qualitative analysis by explain and interpret data from each component evaluated and using model evaluation of CIPP (Context, Input, Process, Product). Sources of data in this study include inclusive education experts, officer of Education Department, school principal, teachers, normal students, and students with special needs. The data were collected by documentation, observation, and interview. The research on contextual component show that the legal process of inclusive education has been shown clearly according to regulation of Education System in Indonesia. The purpose of inclusive education is already in accordance with that has been formulated. Input component indicate that the number of students with special needs enrolled in schools is large enough with various types of disorders. Teachers, curriculum, and infrastructure facilities still have to be improved. The components of process indicate that the plan, process and evaluation activities for each aspect are considered good and good enough. The product shows that the academic aspect of students with special needs based on School Examinations value is considered good and the social aspect is good.This research gives recommendation for government and inclusive school to improve their program preparation more optimal.Keywords: Evaluation Program, Inclusive EducationABSTRAKPenelitian ini bertujuan untuk mengevaluasi implementasi program pendidikan inklusi. Metode yang digunakan adalah analisis kualitatif yaitu mendeskripsikan dan memaknai data dari masing-masing komponen yang dievaluasi dengan menggunakan model evaluasi CIPP (Context, Input, Process, Product). Sumber data dalam penelitian ini meliputi pakar pendidikan inklusi, Dinas Pendidikan, kepala sekolah, guru, siswa normal, dan siswa berkebutuhan khusus. Pengumpulan data dilakukan dengan dokumentasi, observasi, dan wawancara. Hasil temuan komponen konteks menunjukkan bahwa landasan hukum penyelenggaraan pendidikan inklusi secara jelas sudah tertuang dan ditemukan dalam UU Sistem Pendidikan Negara kita. Tujuan pendidikan inklusi pun sudah sesuai dengan yang telah dirumuskan. Hasil temuan komponen input menunjukkan input ABK yang bersekolah jumlahnya cukup banyak dengan berbagai jenis kebutuhan khususnya. Namun dalam komponen guru, kurikulum, dan sarana prasarana masih harus ditingkatkan lagi. Hasil temuan komponen proses menunjukkan kegiatan perencanaan, proses dan evaluasi pembelajaran untuk setiap aspek dinilai masuk dalam katagori baik dan cukup baik. Hasil temuan komponen produk menunjukkan produk perkembangan aspek akademik ABK berdasarkan nilai UAS dinilai cukup baik dan aspek sosialnya pun sudah baik. Penelitian ini memberikan rekomendasi untuk pemerintah dan pihak sekolah penyelenggara inklusi agar lebih meningkatkan kesiapannya dalam menjalankan program pendidikan inklusi yang lebih optimal.Kata Kunci: Evaluasi Program, Pendidikan Inklusi
PENGARUH KONSEP DIRI DAN POLA ASUH ORANG TUA TERHADAP KEMANDIRIAN BELAJAR MAHASISWA PGSD
Authors: Mirawati Mira , Yunita Nita
Published: April 2020

ABSTRAKTujuan penelitian ini untuk mengetahui pengaruh konsep diri serta pola asuh orang tua terhadap kemandirian belajar mahasiswa. Penelitian ini dilaksanakan pada mahasiswa PGSD kelas IVE dan IVF dengan jumlah sampel sebanyak 56 orang dengan teknik sampling jenuh. Metode yang digunakan yaitu survei dengan pendekatan kausalitas. Teknik analisis data menggunakan uji statistik korelasi, regresi linier sederhana dan regresi linier berganda. Pengujian hipotesis dilakukan dengan taraf signifikansi 0,05.Hasil penelitian menghasilkan tiga kesimpulan yaitu Pertama, terdapat pengaruh positif dan signifikan antara konsep diri terhadap kemandirian belajar mahasiswa ditunjukkan dengan nilai koefisien korelasi ry1 = 0,596 dan persamaan regresi . Kedua, terdapat pengaruh positif dan signifikan antara pola asuh orang tua terhadap kemandirian belajar mahasiswa ditunjukkan dengan koefisien korelasi ry2= 0,482 dan persamaan regresi . Ketiga, terdapat pengaruh positif dan signifikan secara bersama-sama antara konsep diri dan pola asuh orang tua terhadap kemandirian belajar mahasiswa ditunjukkan dengan nilai koefisien korelasi ry.12= 0,510 dan persamaan regresi . Hasil penelitian menunjukkan bahwa kemandirian belajar mahasiswa dapat ditingkatkan melalui konsep diri dan pola asuh orang tua.Kata Kunci: Konsep Diri, Pola Asuh Orang Tua, Kemandirian Belajar Mahasiswa, PGSDABSTRACTThis research to study the influence self-concept and parenting pattern toward student learning independence. The research applied to PGSD students at IVE and IVF classes with 56 total samples, take with the saturation sampling technique. The conducted survey was using the causality approach. The technique data analysis used is the correlation statistical test, simple regression and double liniear regression. The hypothesis testing managed at the 0,05 significant rate. The research dispatched three conclusions: First, there is a possitive and significant influence between self-concept toward student learning independence with the correlation coefficient rxy = 59,6 and the regression equation . Second, there is a positive and significant influence between parenting pattern toward student learning independence with the correlation coefficient of rxy = 48,2 and the regression equation of . Third, there is a positive and significant influence together between self-concept and parenting pattern toward student learning independence with the correlation coefficient of rxy = 51,0 and the regression equation of . The result of this research is the student learning independence can be improved by the self-concept and the parenting pattern.Keywords: Self-Concept, Parenting Pattern, Student Learning Independence, PGSD
SPEED READING: UNIVERSITY EFL STUDENTS� STRATEGIES AND PERCEPTIONS
Authors: Hidayati Poppy Sofia
Published: April 2020

EFL reading classes are often teacher-centered and only focus on direct knowledge transmission, the emphasis is often put on the production of comprehension rather than the processing skills. This research attempts to maximize the students participation in evaluating the process of reading by using speed reading program, to find out the strategies they use in the reading process, and to know the students perceptions on speed reading in order to enhance their reading comprehension skill in English. The participants of the study are twenty one students of English Education Study Program of Faculty of Teachers Training and Educational Sciences, in the fifth semester of 2017/2018 academic year. The data were collected from the students reading graphs, reflection journals, and interview. The major findings of this research are: (1) the average of students reading rate is below the ideal speed 300 wpm, but the average result of comprehension score is excellent. Both reading rate and reading comprehension show a progress. (2) Most of the students had used cognitive strategies and unconsciously used metacognitive strategies also. (3) Most of the students showed positive perceptions toward the speed reading program, they were also motivated and able to evaluate themselves to develop their reading skill. It can be concluded that at this level, they have acquired some reading skills and strategies, and by evaluating and recognizing their own weaknesses, they have tried to improve themselves to get better.Keywords: EFL, Case Study, Speed Reading, Strategy, Perception
MODEL MULTILITERASI SOSIAL DALAM MEMAKNAI NILAI-NILAI MORALITAS SISWA DI SDN 1 CIKALAHANG
Authors: Sugiarti Iis Yeni , Hayati Auliya Aenul
Published: April 2020

THE SOCIAL MULTILITERATION MODEL IN UNDERSTANDING THE VALUES OF STUDENT MORALITIES IN SDN 1 CIKALAHANGLearning that has been done so far only emphasizes the cognitive aspects without introducing the moral values. The social multiliteration learning model in understanding the moral values of students is considered very important because students are required to master an understanding of social phenomena and global demands. Therefore, life skills and careers can be built in students; responsibilities in learning; working and creating; students' ability in civilization; and understand the moral knowledge contained in the learning process. This study aims to describe the needs of learning model and design social multiliteration learning model in understanding the values of morality of students at SDN 1 Cikalahang. The writer uses a case study research with a qualitative approach. Observation and interview used to collect the data. Questionnaire needs and unstructured interviews used as the instruments. Indicators of needs analysis include models, media, competencies and evaluation of learning. Analysis of the needs for learning model obtained a total score of 94 which is very good category, while the design of social multiliteration learning model in interpreting moral responsibility is very necessary because the current morality of students is decreasing. The implementation of social multiliteration learning models can help students in interpreting the moral knowing of responsibility character through the activities of raising rabbits, as well as seen from the effectiveness and attractiveness of student learning interests.
Stochastic Models to Qualify Stem Tapers
Authors: Petrauskas Edmundas , Rupšys Petras , Narmontas Martynas , Aleinikovas Marius , Beniušienė Lina , Šilinskas Benas
Published: April 2020

This study examines the performance of 11 tree taper models to predict the diameter of bark at any given height and the total stem volume of eight dominant tree species in the boreal forests of Lithuania. Here, we develop eight new models using stochastic differential equations (SDEs). The symmetrical Vasicek model and asymmetrical Gompertz model are used to describe tree taper evolution, as well as geometric-type diffusion processes. These models are compared with those traditionally used for four tree taper models by using performance statistics and residual analysis. The observed dataset consists of longitudinal measurements of 3703 trees, representing the eight dominant tree species in Lithuania (pine, spruce, oak, ash, birch, black alder, white alder, and aspen). Overall, the best goodness of fit statistics of diameter predictions produced the SDE taper models. All results have been implemented in the Maple computer algebra system using the “Statistics” and “VectorCalculus” packages.
Aeroelastic Wing Planform Design Optimization of a Flutter UAV Demonstrator
Authors: Hermanutz Andreas , Hornung Mirko
Published: April 2020

In this work, a study to design a highly flexible flutter demonstrator for the development and testing of active flutter suppression is presented. Based on the UAV mission, a bi-objective design optimization problem can be formulated. The aeroelastic UAV characteristic and imposed constraints, defined by operational aspects and the structural integrity are described by surrogate modeling. Within the framework of the multi-criteria optimization, an approach to construct the equally spaced Pareto frontier with a new approach for non-convex problems is presented. An efficient Pareto configuration to meet a natural low speed and low frequency is identified and its main influencing design features are analyzed.
Experimental and Numerical Icing Penalties of an S826 Airfoil at Low Reynolds Numbers
Authors: Hann Richard , Hearst R. Jason , Sætran Lars Roar , Bracchi Tania
Published: April 2020

Most icing research focuses on the high Reynolds number regime and manned aviation. Information on icing at low Reynolds numbers, as it is encountered by wind turbines and unmanned aerial vehicles, is less available, and few experimental datasets exist that can be used for validation of numerical tools. This study investigated the aerodynamic performance degradation on an S826 airfoil with 3D-printed ice shapes at Reynolds numbers Re = 2 × 105, 4 × 105, and 6 × 105. Three ice geometries were obtained from icing wind tunnel experiments, and an additional three geometries were generated with LEWICE. Experimental measurements of lift, drag, and pressure on the clean and iced airfoils have been conducted in the low-speed wind tunnel at the Norwegian University of Science and Technology. The results showed that the icing performance penalty correlated to the complexity of the ice geometry. The experimental data were compared to computational fluid dynamics (CFD) simulations with the RANS solver FENSAP. Simulations were performed with two turbulence models (Spalart Allmaras and Menter’s k-ω SST). The simulation data showed good fidelity for the clean and streamlined icing cases but had limitations for complex ice shapes and stall.
Physiological and Biochemical Responses to Salt Stress of Alfalfa Populations Selected for Salinity Tolerance and Grown in Symbiosis with Salt-Tolerant Rhizobium
Authors: Bertrand Annick , Gatzke Craig , Bipfubusa Marie , Lévesque Vicky , Chalifour Francois P. , Claessens Annie , Rocher Solen , Tremblay Gaëtan F. , Beauchamp Chantal J.
Published: April 2020

Alfalfa and its rhizobial symbiont are sensitive to salinity. We compared the physiological responses of alfalfa populations inoculated with a salt-tolerant rhizobium strain, exposed to five NaCl concentrations (0, 20, 40, 80, or 160 mM NaCl). Two initial cultivars, Halo (H-TS0) and Bridgeview (B-TS0), and two populations obtained after three cycles of recurrent selection for salt tolerance (H-TS3 and B-TS3) were compared. Biomass, relative water content, carbohydrates, and amino acids concentrations in leaves and nodules were measured. The higher yield of TS3-populations than initial cultivars under salt stress showed the effectiveness of our selection method to improve salinity tolerance. Higher relative root water content in TS3 populations suggests that root osmotic adjustment is one of the mechanisms of salt tolerance. Higher concentrations of sucrose, pinitol, and amino acid in leaves and nodules under salt stress contributed to the osmotic adjustment in alfalfa. Cultivars differed in their response to recurrent selection: under a 160 mM NaCl-stress, aromatic amino acids and branched-chain amino acids (BCAAs) increased in nodules of B-ST3 as compared with B-TS0, while these accumulations were not observed in H-TS3. BCAAs are known to control bacteroid development and their accumulation under severe stress could have contributed to the high nodulation of B-TS3.
Synergy between Florfenicol and Aminoglycosides against Multidrug-Resistant Escherichia coli Isolates from Livestock
Authors: Kim Shukho , Woo Jung Hwa , Jun So Hyun , Moon Dong Chan , Lim Suk-Kyung , Lee Je Chul
Published: April 2020

The increasing prevalence of antimicrobial resistance and the laborious development of novel antimicrobial agents have limited the options for effective antimicrobial therapy. The combination of previously used antimicrobial agents represents an alternative therapy for multidrug-resistant (MDR) pathogens. The objective of this study was to investigate the synergistic effect of a florfenicol (FFL)-based combination with other antimicrobial agents against MDR Escherichia coli isolates from livestock using checkerboard assays and murine infection models. The FFL/amikacin (AMK) and FFL/gentamicin (GEN) combinations showed synergy against 10/11 and 6/11 MDR E. coli isolates in vitro, respectively. The combination of FFL with aminoglycosides (AMK or GEN) exhibited a better synergistic effect against MDR E. coli isolates than the cephalothin (CEF)/GEN or FFL/CEF combinations. The combination of FFL with AMK or GEN could reduce the emergence of resistant mutants in vitro. The FFL/AMK combination showed a higher survival rate of mice infected with MDR E. coli isolates than FFL or AMK alone. In summary, the combination of FFL with aminoglycosides (AMK or GEN) is highly effective against MDR E. coli isolates both in vitro and in vivo. Our findings may contribute to the discovery of an effective combination regimen against MDR E. coli infections in veterinary medicine.
Gas Plasma-Treated Prostate Cancer Cells Augment Myeloid Cell Activity and Cytotoxicity
Authors: Bekeschus Sander , Ressel Verena , Freund Eric , Gelbrich Nadine , Mustea Alexander , B. Stope Matthias
Published: April 2020

Despite recent improvements in cancer treatment, with many of them being related to foster antitumor immunity, tumor-related deaths continue to be high. Novel avenues are needed to complement existing therapeutic strategies in oncology. Medical gas plasma technology recently gained attention due to its antitumor activity. Gas plasmas act via the local deposition of a plethora of reactive oxygen species (ROS) that promote the oxidative cancer cell death. The immunological consequences of plasma-mediated tumor cell death are only poorly understood, however. To this end, we exposed two prostate cancer cell lines (LNCaP, PC3) to gas plasma in vitro, and investigated the immunomodulatory effects of the supernatants in as well as of direct co-culturing with two human myeloid cell lines (THP-1, HL-60). After identifying the cytotoxic action of the kINPen plasma jet, the supernatants of plasma-treated prostate cancer cells modulated myeloid cell-related mitochondrial ROS production and their metabolic activity, proliferation, surface marker expression, and cytokine release. Direct co-culture amplified differentiation-like surface marker expression in myeloid cells and promoted their antitumor-toxicity in the gas plasma over the untreated control conditions. The results suggest that gas plasma-derived ROS not only promote prostate cancer cell death but also augment myeloid cell activity and cytotoxicity.
Opportunities for Two-Color Experiments in the Soft X-ray Regime at the European XFEL
Authors: Serkez Svitozar , Decking Winfried , Froehlich Lars , Gerasimova Natalia , Grünert Jan , Guetg Marc , Huttula Marko , Karabekyan Suren , Koch Andreas , Kocharyan Vitali , Kot Yauhen , Kukk Edwin , Laksman Joakim , Lytaev Pavel , Maltezopoulos Theophilos , Mazza Tommaso , Meyer Michael , Saldin Evgeni , Schneidmiller Evgeny , Scholz Matthias , Tomin Sergey , Vannoni Maurizio , Wohlenberg Torsten , Yurkov Mikhail , Zagorodnov Igor , Geloni Gianluca
Published: April 2020

X-ray pump/X-ray probe applications are made possible at X-ray Free Electron Laser (XFEL) facilities by generating two X-ray pulses with different wavelengths and controllable temporal delay. In order to enable this capability at the European XFEL, an upgrade project to equip the soft X-ray SASE3 beamline with a magnetic chicane is underway. In the present paper we describe the status of the project, its scientific focus and expected performance, including start-to-end simulations of the photon beam transport up to the sample, as well as recent experimental results demonstrating two-color lasing at photon energies of 805 eV + 835 eV and 910 eV + 950 eV. Additionally, we discuss methods to analyze the spectral properties and the intensity of the generated radiation to provide on-line diagnostics for future user experiments.
Study on Penetration Sensing Method Based on Pool Oscillation and Arc Voltage during Pulsed GMAW
Authors: Chen Tao , Xue Songbai , Zhai Peizhuo , Wang Bo , Long Weimin
Published: April 2020

The internal relations among the oscillation characteristics of the weld pool, the voltage signal curve and the penetration status of the weld joint in pulsed gas metal arc welding were investigated by using high-speed camera and image analysis system to extract characteristics of weld pool oscillation. The results show that the amplitude of weld pool oscillation decreased with decreasing weld penetration. An abrupt change occurred in the frequency components and amplitude of weld pool oscillation, accompanying the transition from partial to full penetration. The voltage signal curve lost the oscillation frequency characteristic of the pool, due to the curvature of the weld pool surface. While similar to the oscillation amplitude, the fluctuation of the voltage signal caused by the weld pool oscillation reflected the penetration of the weld pool. The abrupt transition in the fluctuation amplitude of the voltage signal in the base duration from partial penetration to full penetration may be used to sense the penetration of the weld pool in real time.
Application of USCCD on Girth Weld Defect Detection of Oil Pipelines
Authors: Dai L. S. , Feng Q. S. , Xiang X. Q. , Sutherland J. , Wang T. , Wang D. P. , Wang Z. J.
Published: April 2020

Globally, more and more attention has been paid to the integrity of Girth Welds (GW) of oil and gas pipelines due to their failures with high consequences. A primary concern is that defects originate during field construction but over time may be subject to external loads due to earth movement. GW defects in newly built pipelines are also assumed to exist but would be much smaller in size, and more difficult to detect, which motivated the investigation into minimum defect detection capabilities of the inspection technologies. This study presents the evaluation results of UltraScan™ Circumferential Crack-Like Detection (USCCD) technology for oil pipeline GW inspection, based upon the pull test and in field data from Inline Inspection (ILI) of pipeline by PetroChina Pipeline Company (PPC) using GE PII (General Electric Company, Pipeline Integrity Inspection) 32” UltraScan™ CCD Tool. The performance of USCCD is given according to the ILI data, pull test results and dig NDE (Non-Destructive Examination). It can be concluded that crack-like defects with clear edges can be detected during ultrasonic propagation; however, the irregular shape of weld makes the inspection more difficult. It is still a challenge to identify the type of defects, and depth sizing can only be classified not quantified, which would require more excavations. However, this technology is feasible for the alternative technology of GW defect inspection.
A Survey on Theories and Applications for Self-Driving Cars Based on Deep Learning Methods
Authors: Ni Jianjun , Chen Yinan , Chen Yan , Zhu Jinxiu , Ali Deena , Cao Weidong
Published: April 2020

Self-driving cars are a hot research topic in science and technology, which has a great influence on social and economic development. Deep learning is one of the current key areas in the field of artificial intelligence research. It has been widely applied in image processing, natural language understanding, and so on. In recent years, more and more deep learning-based solutions have been presented in the field of self-driving cars and have achieved outstanding results. This paper presents a review of recent research on theories and applications of deep learning for self-driving cars. This survey provides a detailed explanation of the developments of self-driving cars and summarizes the applications of deep learning methods in the field of self-driving cars. Then the main problems in self-driving cars and their solutions based on deep learning methods are analyzed, such as obstacle detection, scene recognition, lane detection, navigation and path planning. In addition, the details of some representative approaches for self-driving cars using deep learning methods are summarized. Finally, the future challenges in the applications of deep learning for self-driving cars are given out.
Fatigue Life Analysis of Ball Bearings and a Shaft System Considering the Combined Bearing Preload and Angular Misalignment
Authors: Zhang Yu , Zhang Mengqi , Wang Yawen , Xie Liyang
Published: April 2020

Bearing preload significantly affects the running performance of a shaft-bearing system including the fatigue life, wear, and stiffness. Due to the mounting error, the bearing rings are often angularly misaligned. The effects of the combined bearing preload and angular misalignment on the fatigue life of ball bearings and a shaft-bearing system are analyzed in this paper. The contact force distribution of angular contact ball bearings in the shaft-bearing system is investigated based on the system model. The system model includes the bearing model, and the shaft model is verified by comparing with the manufacturer’s manual and the results from other theoretical models, with the difference between the results from the present bearing model and manufacturer manual within 3%. The global optimization method is used to replace the Newton–Raphson algorithm to solve the ball elements’ displacements and friction coefficients, which improves the computation efficiency of the system model. The fatigue life of each bearing is evaluated with the consideration of the two preload methods and two angular misalignment cases. The fatigue life results show that the system life at the optimal angular misalignment is more than 1.5 times that without angular misalignment at the low preload value, and this ratio decreases as the preload value increases. The optimal angular misalignment of both the shaft-bearing system and the misaligned bearing is not always consistent, which depends on the preload value and bearing life. Both the constant-displacement preload and constant-force preload do not cause a significant difference in the highest system life. The different misaligned bearings can lead to different highest system lives as the preload value is low.
Reduction of Coupling Interface Degrees of Freedom in Mixed-Interface Component Mode Synthesis
Authors: Tang Yu , Qin Hui
Published: April 2020

A new coupling interface degrees of freedom (DOFs) reduction technique for the mixed-interface component mode synthesis (MCMS) method is proposed, which referred to as the MCMS-rid method. This approach employs a set of shape functions via the linear interpolation (LI) in finite element method (FEM) to realize interface nodal coordinate transformations for each substructure, and then only a small number of interpolation basic nodes (IBNs) will be involved in mode synthesis and the following dynamic analysis. Unlike the majority of available CMS methods that retain a full dimension of the coupling interface DOFs, the MCMS-rid method allows to reduce the coupling interface DOFs significantly and enhance the computational efficiency. Three numerical models, including a rectangular beam with two ends fixed, a non-rectangular beam with the button fixed and a simplified dam-foundation system with different material properties, are presented to demonstrate the computational accuracy and efficiency of the proposed method. The results indicate that favourable accuracy with a least number of retained DOFs involved in mode synthesis can be obtained for solving eigenvalue problems when compared with other MCMS methods. The optimal number and distribution of the IBNs are discussed on structural dynamic analysis as well. It is shown that the more the IBNs are involved in mode synthesis, the better the precision that will be received. Furthermore, when the sub-regions are nearly square, the precision is best.
Effects of di-(2-ethylhexyl) phthalate on Transcriptional Expression of Cellular Protection-Related HSP60 and HSP67B2 Genes in the Mud Crab Macrophthalmus japonicus
Authors: Park Kiyun , Kim Won-Seok , Kwak Ihn-Sil
Published: April 2020

Di-2-ethylhexyl phthalate (DEHP) has attracted attention as an emerging dominant phthalate contaminant in marine sediments. Macrophthalmus japonicus, an intertidal mud crab, is capable of tolerating variations in water temperature and sudden exposure to toxic substances. To evaluate the potential effects of DEHP toxicity on cellular protection, we characterized the partial open reading frames of the stress-related heat shock protein 60 (HSP60) and small heat shock protein 67B2 (HSP67B2) genes of M. japonicus and further investigated the molecular effects on their expression levels after exposure to DEHP. Putative HSP60 and small HSP67B2 proteins had conserved HSP-family protein sequences with different C-terminus motifs. Phylogenetic analysis indicated that M. japonicus HSP60 (Mj-HSP60) and M. Japonicus HSP67B2 (Mj-HSP67B2) clustered closely with Eriocheir sinensis HSP60 and Penaeus vannamei HSP67B2, respectively. The tissue distribution of Heat shock proteins (HSPs) was the highest in the gonad for Mj-HSP60 and in the hepatopancreas for Mj-HSP67B2. The expression of Mj-HSP60 Messenger Ribonucleic Acid (mRNA) increased significantly at day 1 after exposure to all doses of DEHP, and then decreased in a dose-dependent and exposure time-dependent manner in the gills and hepatopancreas. Mj-HSP67B2 transcripts were significantly upregulated in both tissues at all doses of DEHP and at all exposure times. These results suggest that cellular immune protection could be disrupted by DEHP toxicity through transcriptional changes to HSPs in crustaceans. Small and large HSPs might be differentially involved in responses against environmental stressors and in detoxification in M. japonicus crabs.
DDTree: A Hybrid Deep Learning Model for Real-Time Waterway Depth Prediction and Smart Navigation
Authors: Yang Fan , Qiao Yanan , Wei Wei , Wang Xiao , Wan Difang , Damaševičius Robertas , Woźniak Marcin
Published: April 2020

Timely and accurate depth estimation of a shallow waterway can improve shipping efficiency and reduce the danger of waterway transport accidents. However, waterway depth data measured during actual maritime navigation is limited, and the depth values can have large variability. Big data collected in real time by automatic identification systems (AIS) might provide a way to estimate accurate waterway depths, although these data include no direct channel depth information. We suggest a deep neural network (DNN) based model, called DDTree, for using the real-time AIS data and the data from Global Mapper to predict waterway depth for ships in an accurate and timely way. The model combines a decision tree and DNN, which is trained and tested on the AIS and Global Mapper data from the Nantong and Fangcheng ports on the southeastern and southwestern coast of China. The actual waterway depth data were used together with the AIS data as the input to DDTree. The latest data on waterway depths from the Chinese maritime agency were used to verify the results. The experiments show that the DDTree model has a prediction accuracy of 91.15%. Therefore, the DDTree model can provide an accurate prediction of waterway depth and compensate for the shortage of waterway depth monitoring means. The proposed hybrid DDTree model could improve marine situational awareness, navigation safety, and shipping efficiency, and contribute to smart navigation.
Structural Features Guiding the Design of Liquid-Crystalline Elastomeric Fluorescent Force Sensors
Authors: Garcia-Amorós Jaume , Velasco Dolores
Published: April 2020

Liquid single crystal elastomers (LSCEs) containing carbazole fluorogenic components alter their luminescence when they are stretched along the director direction. The differential luminescent behavior arises from the distinct interaction between the carbazole fluorophores and their local environment before and after the application of the mechanical input. Indeed, the uniaxial deformation of the material, along its anisotropic direction, forces a closer mesogen–fluorophore interaction, which leads to the quenching of the carbazole luminescence. Importantly, this intermolecular interaction is intimately related to the intrinsic order present in the LSCE. As a result, the amount of light emitted by the material in the form of fluorescence diminishes upon deformation. Thus, the application of mechanical stimuli to liquid-crystalline elastomers furnishes to two interconvertible states for the system with distinct optical properties (with either different emission color or fluorescence intensity). The initial state of the material is completely restored once the applied force is removed. In this way, this kind of macromolecular system can transduce mechanical events into detectable and processable optical signals, thus, having great potential as optical force sensors. In this context, the realization of the distinct structural factors that govern the interactions established between the mesogenic and fluorogenic units at the supramolecular level upon deformation is essential for the development of efficient LSCE-based force sensors. In fact, not only the density of carbazole units and their connection to the main polymer backbone, but also the presence of long range molecular order in the system and the type of mesophase exhibited by the LSCE are key factors for the conception of efficient force sensors based on these self-organized polymer networks. In this review, we present a comprehensive and systematic description of the different features that control the mechanoluminescent behavior of fluorescent liquid-crystalline elastomers and will guide the future design of LSCE-based force sensors with improved performances.
Significant Contribution of Primary Sources to Water-Soluble Organic Carbon During Spring in Beijing, China
Authors: Jin Yali , Yan Caiqing , Sullivan Amy P. , Liu Yue , Wang Xinming , Dong Huabin , Chen Shiyi , Zeng Limin , Collett, Jr. Jeffrey L. , Zheng Mei
Published: April 2020

Despite the significant role water-soluble organic carbon (WSOC) plays in climate and human health, sources and formation mechanisms of atmospheric WSOC are still unclear; especially in some heavily polluted areas. In this study, near real-time WSOC measurement was conducted in Beijing for the first time with a particle-into-liquid-sampler coupled to a total organic carbon analyzer during the springtime, together with collocated online measurements of other chemical components in fine particulate matter with a 1 h time resolution, including elemental carbon (EC), organic carbon (OC), multiple metals, and water-soluble ions. Good correlations of WSOC with primary OC, as well as carbon monoxide, indicated that major sources of WSOC were primary instead of secondary during the study period. The positive matrix factorization model-based source apportionment results quantified that 68 ± 19% of WSOC could be attributed to primary sources, with predominant contributions by biomass burning during the study period. This finding was further confirmed by the estimate with the modified EC-tracer method, suggesting significant contribution of primary sources to WSOC. However, the relative contribution of secondary source to WSOC increased during haze episodes. The WSOC/OC ratio exhibited similar diurnal distributions with O3 and correlated well with secondary WSOC, suggesting that the WSOC/OC ratio might act as an indicator of secondary formation when WSOC was dominated by primary sources. This study provided evidence that primary sources could be major sources of WSOC in some polluted megacities, such as Beijing. From this study, it can be seen that WSOC cannot be simply used as a surrogate of secondary organic aerosol, and its major sources could vary by season and location.
Bioaerosol in Composting Facilities: A Survey on Full-Scale Plants in Italy
Authors: Anedda Elisa , Traversi Deborah
Published: April 2020

Bioaerosols lead to human health diseases and composting plants are one of the main sources among human activities. In this study, a survey was conducted on such plants to evaluate bioaerosol risk management. A questionnaire was used to collect information on plant location, process types, collective and personal protective equipment, bioaerosol and particulate matter monitoring data, and occupational surveillance. We examined the data produced by 11 plants located in Italy. Self-control bioaerosol monitoring showed a global contamination index mean of 9908 CFU/m3 underlining a higher concentration (a) in plants with only aerobic process (CPs) with respect to plants that also combined anaerobic treatment of the waste (ADCPs) (p < 0.05) and (b) in facilities with biocells with respect to windrows (p < 0.01). Workers are generally more exposed when working without vehicles. Some areas such as pre-treatment and screening are more prone to higher bioaerosol concentrations, requiring more efficient collective protective equipment. Particulate matter monitoring showed concentration in line with occupational exposure limits for inhalable dust (1862 ± 1729 µg/m3) and breathable dust (276 ± 126 µg/m3), however, organic particle exposure risk assessment has to be carefully reviewed. Improvements in the training program, process design, and health surveillance are desirable as major preventive tools.
Human vtRNA1-1 Levels Modulate Signaling Pathways and Regulate Apoptosis in Human Cancer Cells
Authors: Bracher Lisamaria , Ferro Iolanda , Pulido-Quetglas Carlos , Ruepp Marc-David , Johnson Rory , Polacek Norbert
Published: April 2020

Regulatory non-protein coding RNAs perform a remarkable variety of complex biological functions. Previously, we demonstrated a role of the human non-coding vault RNA1-1 (vtRNA1-1) in inhibiting intrinsic and extrinsic apoptosis in several cancer cell lines. Yet on the molecular level, the function of the vtRNA1-1 is still not fully clear. Here, we created HeLa knock-out cell lines revealing that prolonged starvation triggers elevated levels of apoptosis in the absence of vtRNA1-1 but not in vtRNA1-3 knock-out cells. Next-generation deep sequencing of the mRNome identified the PI3K/Akt pathway and the ERK1/2 MAPK cascade, two prominent signaling axes, to be misregulated in the absence of vtRNA1-1 during starvation-mediated cell death conditions. Expression of vtRNA1-1 mutants identified a short stretch of 24 nucleotides of the vtRNA1-1 central domain as being essential for successful maintenance of apoptosis resistance. This study describes a cell signaling-dependent contribution of the human vtRNA1-1 to starvation-induced programmed cell death.
Green Tea Catechin (-)-Epigallocatechin-3-Gallate (EGCG) Facilitates Fracture Healing
Authors: Lin Sung-Yen , Kan Jung Yu , Lu Cheng-Chang , Huang Han Hsiang , Cheng Tsung-Lin , Huang Hsuan-Ti , Ho Cheng-Jung , Lee Tien-Ching , Chuang Shu-Chun , Lin Yi-Shan , Kang Lin , Chen Chung-Hwan
Published: April 2020

Green tea drinking can ameliorate postmenopausal osteoporosis by increasing the bone mineral density. (-)-Epigallocatechin-3-gallate (EGCG), the abundant and active compound of tea catechin, was proven to be able to reduce bone loss and ameliorate microarchitecture in female ovariectomized rats. EGCG can also enhance the osteogenic differentiation of murine bone marrow mesenchymal stem cells and inhibit the osteoclastogenesis in RAW264.7 cells by modulation of the receptor activator of nuclear factor-kB (RANK)/RANK ligand (RANKL)/osteoprotegrin (OPG) (RANK/RANKL/OPG) pathway. Our previous study also found that EGCG can promote bone defect healing in the distal femur partially via bone morphogenetic protein-2 (BMP-2). Considering the osteoinduction property of BMP-2, we hypothesized that EGCG could accelerate the bone healing process with an increased expression of BMP-2. In this manuscript, we studied whether the local use of EGCG can facilitate tibial fracture healing. Fifty-six 4-month-old rats were randomly assigned to two groups after being weight-matched: a control group with vehicle treatment (Ctrl) and a study group with 10 µmol/L, 40 µL, EGCG treatment (EGCG). Two days after the operation, the rats were treated daily with EGCG or vehicle by percutaneous local injection for 2 weeks. The application of EGCG enhanced callus formation by increasing the bone volume and subsequently improved the mechanical properties of the tibial bone, including the maximal load, break load, stiffness, and Young’s modulus. The results of the histology and BMP-2 immunohistochemistry staining showed that EGCG treatment accelerated the bone matrix formation and produced a stronger expression of BMP-2. Taken together, this study for the first time demonstrated that local treatment of EGCG can accelerate the fracture healing process at least partly via BMP-2.
Cancer Classification at the Crossroads
Authors: Carbone Antonino
Published: April 2020

Internationally accepted classifications of malignant tumors, developed by the World Health Organization (WHO) and the Union for International Cancer Control (UICC), are based on the histotype, site of origin, morphologic grade, and spread of cancer throughout the body. The WHO classifications are the foundation of cancer diagnosis and the starting point for cancer management. Starting in 2000, the WHO classifications began to include biologic and molecular–genetic features. These developments are having a strong impact on cancer diagnosis and treatment, and this impact is amplifying, given the advances in cancer genomics. Molecular–genetic profiling can be used to refine existing classifications of tumors and, for a small but increasing number of cancers, even determine the treatment irrespective of histotype. Here I discuss how cancer classifications may change in the era of cancer genomics.
Comparison of Minimally Invasive versus Open Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma: A Propensity Score Matching Analysis
Authors: Kwon Jaewoo , Song Ki Byung , Park Seo Young , Shin Dakyum , Hong Sarang , Park Yejong , Lee Woohyung , Lee Jae Hoon , Hwang Dae Wook , Kim Song Cheol
Published: April 2020

Background: Few studies have compared perioperative and oncological outcomes between minimally invasive pancreatoduodenectomy (MIPD) and open pancreatoduodenectomy (OPD) for pancreatic ductal adenocarcinoma (PDAC). Methods: A retrospective review of patients undergoing MIPD and OPD for PDAC from January 2011 to December 2017 was performed. Perioperative, oncological, and survival outcomes were analyzed before and after propensity score matching (PSM). Results: Data from 1048 patients were evaluated (76 MIPD, 972 OPD). After PSM, 73 patients undergoing MIPD were matched with 219 patients undergoing OPD. Operation times were longer for MIPD than OPD (392 vs. 327 min, p < 0.001). Postoperative hospital stays were shorter for MIPD patients than OPD patients (12.4 vs. 14.2 days, p = 0.040). The rate of overall complications and postoperative pancreatic fistula did not differ between the two groups. Adjuvant treatment rates were higher following MIPD (80.8% vs. 59.8%, p = 0.002). With the exception of perineural invasion, no differences were seen between the two groups in pathological outcomes. The median overall survival and disease-free survival rates did not differ between the groups. Conclusions: MIPD showed shorter postoperative hospital stays and comparable perioperative and oncological outcomes to OPD for selected PDAC patients. Future randomized studies will be required to validate these findings.