bluuebunny/crossref_metadata_2025_split huggingface dataset:
The analysis of students’ ability in solving physics problems using multiple representations
Authors: Sutriani  , Mansyur J. 
Published: January 2021

AbstractThe ability and skills of students in using multiple representations determine the level of students’ physics problem solving abilities. Students’ thinking ability in solving physics problems tends to vary. Therefore, this study was conducted to analyze the students’ ability to solve physics problems by using multiple representations. The type of research was a qualitative research which utilized qualitative descriptive approach. The subjects in this study were 19 students of class XI Science An-Nahl MA Negeri Insan Cendikia Palu City in the 2019/2020 academic year. Respondents in this study were 6 students selected based on the high, medium, and low categories obtained from the results of the respondent selection test. The instruments used in this study were multiple choice tests, problem-solving tests, and interview guides. Based on the results of this study, the students’ physics problem solving ability was categorized in the poor category with the acquisition of an average score in percentage of 37.89%, while for the highest average multi-representation ability of each representation, namely pictures, graphics, mathematics, and verbal, students tended to be able to use image representations with a percentage of 38.75%. However, this percentage was still categorized as low.
The students’ approach patterns in thermodynamic problem-solving at SMA lab school UNTAD Palu
Authors: Susanti  , Supriyatman  
Published: January 2021

Abstract
The process of problem-solving carried out by students in solving physics exercises consists of different approaches. It is reviewed based on the diversity of students’ ability levels in solving problems in physics subject. This study aims to describe the approach patterns used by students in the process of solving physics problems on the thermodynamic material at Senior High School Lab school UNTAD Palu. This type of research is qualitative research with a qualitative descriptive approach. The subjects in this study were 20 students of Grade XI Science 3 at Senior High Scool Labchool UNTAD Palu. Respondents in this study consisted of up to 6 students. The respondents were selected using the calculation of standard deviation and the average score of the results of the respondent selection test. The instruments used in this study were respondent selection tests, problem-solving tests, and interview guides. From the results of the research for the test of students’ physics, the problem-solving ability was in the poor category with the acquisition of an average value percentage of 37.3%. Meanwhile, the approach patterns used by the students in the physics problem-solving process was interesting as it tended to use two approaches, namely structured Plug and Chug, as well as unstructured Plug and Chug.
An online project-based learning model to improve students’ thinking ability in the new normal era
Authors: Bhakti C P , Noor K W , Ghiffari M A N , Nurpitasari E , Oktradiksa A , Ani  
Published: January 2021

Abstract
The purpose of this paper is to provide insight into project-based learning conducted online to improve students’ thinking skills in the new normal era. In the new normal situation, students must carry out learning at home online. The method used in this study is a literature review. Benefits and competency development of online learning need to be considered. One of the competencies that need to be developed in the new normal is the ability to think. Unlike before the COVID 19 pandemic outbreak, students’ thinking skills can be developed through face-to-face learning with teachers and peers. However, in this new normal era, there is a need to modify online learning strategies to improve thinking skills. Project-based learning is a learning strategy in which learning orientation is carried out by doing long-term assignments. Project-based learning can be done online and adapted to the current new normal situation. This research using a literature review method which used several stages started from collection data until summarized the data. It can be concluded that this research will give a reference to produce a website for improving students’ thinking ability.
The effectiveness of distance learning through Edmodo and Video Conferencing Jitsi Meet
Authors: Asfar A M I T , Asfar A M I A 
Published: January 2021

Abstract
Distance learning is intensively used since the outbreak of the Covid-19 requires the lecture to be done from home. A variety of applications to support distance learning, including e-learning Edmodo as a learning management system with video conference jits meet to optimize lectures online. The purpose of this study is to see the course’s effectiveness by using e-learning Edmodo with or without a video conference Jitsi Meet in reducing students’ mistakes in answering the questions given. Research design using experimental type posttest, only group control design. The object of research consists of two classes, namely class control and class comparison. The analysis results indicate the use of an e-learning Edmodo integrated video conference Jitsi Meet provides advantages compared to only using e-learning Edmodo because it can reduce the level of error in answering questions by 50%.
Students mathematical literacy in solving wetlands contextual problems
Authors: Zulkarnain I , Hidayanto T , Kamaliyah  
Published: January 2021

AbstractThe research describes the students’ mathematical literacy in solving wetlands contextual problems. This study employed a descriptive qualitative method. The subjects were 87 students in Mathematical Learning for Junior High School course of Mathematics Education Study Program at Universitas Lambung Mangkurat in the 2019/2020 academic year. The students were tested with ten items of wetlands contextual problems. The analysis of those data used descriptive statistics including mean, standard deviation, maximum and minimum score, and total score. The research finding reveals that the mean score of students’ mathematical literacy was 18.55 (medium category). Individually, there were five students in very high, 14 students in high, 31 students in medium, 35 students in low, and two students in the very low category. In addition, the students are weak in the formulating process. Based on the result, students’ habituation in solving contextual wetland problems needs to be continuously pursued to improve students’ mathematical literacy ability.
The validity of lesson plan with scientific approach: Building curiosity and responsibility character
Authors: Pasani C F , Yulinda R , Putri R F , Amelia R 
Published: January 2021

AbstractThe instilling of national character value may be achieved through learning. Therefore, this study aims to create a Lesson Plan, which integrates the characters of curiosity and responsibility with a scientific approach and to determine product validity. Research and Development (R&D) was used as a model for conducting this study. The Research and Development used Borg and Gall model. Furthermore, the characteristics of the developed lesson Plan were evident in the syntax/learning steps, which were organized according to curiosity indicators and responsibility characters. This study involved 2 expert validators and 1 school practitioner. The instrument used was a learning plan validation sheet. The results showed that the Lesson Plan with a scientific approach may be used to develop the character of curiosity and responsibility for students in junior high school. This can be seen from the validity of three aspects which is the format (100%), language (98,33%) and content (97,47%) which are very good qualification. It can be concluded that the lesson plan developed is valid and able to building curiosity and responsibility character student.
The development of electrical energy conversion tools as learning media for the concept of energy sources
Authors: Rohman Abdul , Komang Werdhiana I , Saehana Sahrul 
Published: January 2021

Abstract
The purpose of this research is to produce electrical energy conversion tool as a learning medium. This research process is a research and development research which is commonly referred to as R&D. Sugiyono modified this research model. The instrument used was a questionnaire with a Likert scale which were assessed by media experts, material experts, physics teachers and students of Grade XI IPA Senior High School Lab school, Untad, Palu. The product quality data obtained were analyzed using descriptive analysis. The product quality based on the results of the analysis of the media expert’s assessment obtained a percentage value of 84% with the interpretation of “Very Good”. The product quality, based on the results of the assessment analysis by material experts, obtained a percentage value of 85% with the interpretation “Very Good”. For the results of the physics teacher responses on the perspective of the learning media developed, it obtained a percentage value of 92.2% with the interpretation “Strongly Agree”. For the results of the students’ responses in Grade XI Science Senior High School Lab school, Untad, Palu, on the limited test, the percentage value obtained was 85.95% which had the interpretation of, “Strongly Agree” regarding the use of the learning media. The results of the tests and questionnaire analysis indicated that the electric energy conversion tool as a learning medium developed is suitable for use in the learning process.
The effect of TiO2 addition on thermal resistance of geopolymer mortar based low alumina fly ash
Authors: Saukani M , Febrianty R , Ariska N , Husein S , Astutiningsih S 
Published: January 2021

Abstract
The utilization of fly ash with low alumina has been carried out. The addition of TiO2 to the base material of fly ash and fly ash added with 20% metakaolin mixed with an alkaline solution has been characterized by heat resistance, compressive strength and porosity. These results indicate that the addition of TiO2 to both fly ash and fly ash with an additional 20% metakaolin shows a reduction in porosity reduction, an increase in the compressive strength value, and an increase in the thermal resistance of the sample. Despite an increase in the compressive strength value, however, the minimum requirement for a fire brick has not been achieved.
The effect of physics learning with the use of gasing and boat toys media on student learning outcomes
Authors: Widyaparamita  , Darmadi I W , Saehana S 
Published: January 2021

Abstract
This study aimed to determine whether or not there was an effect of learning physics with the media of top games and boat games on student learning outcomes in Junior High School 2 Sigi. To see the success of this study, a pretest was held to determine the students’ abilities. After that, the experimental class was given treatment using the top game media and boat games and the control class did not use games. After learning was complete, both classes were again given a posttest to test the results. Based on the results of the two classes, the mean scores of the experimental class and control class were 9.93 and 11.06 for the pretest respectively, while for the posttest the average scores were 22.5 and 19.10. This study used a quasi-experimental research type. The population of this study were all students of class VIII Junior High School 2 Sigi and the sample in this study were class VIII A and VIII B which were divided into experimental class and control class. The research sample was selected using purposive sampling technique which determined the sample with certain considerations. The instrument used was an essay Test.
Nitrogen accumulation, rather than carbon: nitrogen stoichiometric variation, underlies carbon storage during forest succession
Authors: Zou Junliang , Wu Juying , Osborne Bruce , Tobin Brian , Luo Yiqi 
Published: January 2021

Abstract
Forest ecosystems play an important role in regulating global temperatures through their capability to take up and store CO2 from the atmosphere, but the magnitude and sustainability of this carbon (C) sink is critically dependent on the availability of nutrients, particularly nitrogen (N). However, the extent to which the absolute amount of N or modifications in plant and soil C:N ratios controls long-term forest carbon sequestration (Cseq) remains uncertain. To assess this, we analyzed the results of 135 global field studies that investigated the dynamics of C and N availability during forest succession. The results showed that the accumulation of C and N in plant (including above- and below-ground vegetation) and litter pools decreased with forest age and approached an equilibrium value in the latter stages of stand development. Plant and litter C:N ratios increased during the first 10–20 years and remained relatively stable thereafter. The analysis further showed that the relative importance of a change in the total amount of N or modifications in the C:N ratio, to increases in Cseq, varied with forest age. Whilst the relative importance of a change in the total amount of N increased with forest age, the relative importance of a varied C:N stoichiometry decreased with forest age. Overall, a change in the total amount of N was the more important factor contributing to C storage during forest stand development and the C stored in vegetation dominated the total ecosystem C pool. These results show that ecosystem N availability is a key factor supporting long-term forest Cseq during forest succession. As most of the C is found in above-ground vegetation, this pool is particularly susceptible to abiotic or biotic factors and anthropogenically-related disturbances.
Formation mechanism and function of tribo-layers in dry sliding wear of TC11 alloy
Authors: Li Xinxing , Wang Hongxia , Shi Jianfeng , Han Boqun , Ren Naifei 
Published: January 2021

Abstract
Dry sliding wear tests were performed for TC11 alloy through a pin-on-disc tribometer at a load of 50 N under different sliding velocities. Tribo-layers always formed on wear surfaces of titanium alloy at different sliding speeds. The formation of tribo-layers depended on the generation, movement, aggregation, transfer of wear debris and tribo-chemistry. Small wear debris and relatively high contact surface temperature were favorable conditions for formation of tribo-oxide layers. Tribo-oxide layers protected the titanium alloy matrix effectively and reduced the wear. The more oxides the tribo-oxide layer contained, the better it protected the matrix.
Thermal and mechanical performances of bamboo strip
Authors: Richmond Tutea , Lods Louise , Dandurand Jany , Dantras Eric , Lacabanne Colette , Durand Jean-Michel , Sherwood Edouard , Ponteins Philippe 
Published: January 2021

AbstractBamboo strips extracted from Phyllostachys viridiglaucescens, grown in Europe, were analysed to assess their thermal and mechanical properties for composites application. Thermal stability of the European bamboo was studied by Thermogravimetric Analysis (TGA) and compared to the one of species grown in Oceania. An evolution of the chemical composition along the radial direction of the Phyllostachys bamboo was identified by TGA. The inner part of culms shows a higher proportion of hemicelluloses, while the percentage of crystalline cellulose is higher in the outer portion. This evolution of the composition was used to interpret the original data recorded by Dynamic Mechanical Analysis (DMA) of the strips. Glassy tensile modulus founded by DMA increases from the inner part of the culm (6.8 GPa) to the outer part (9.9 GPa). The variation of the cellulose content along the radius of the bamboo culm is related to this increase and shows a good correlation with thermal behaviour. The dynamic relaxations in the shear mode reveal the existence of two secondary relaxation modes sensitive to water. In the order of increasing temperatures, they have been assigned to the mobility of methylol groups and to heterogeneities of the polymeric matrix. By combining Differential Scanning Calorimetry (DSC) and DMA, the response of the viscoelastic transition of bamboo strips, at 210 °C, was evidenced for the first time. Bamboo strips behave as a unidirectional composite reinforced by technical fibres; its particularly high shear glassy modulus (2.3 GPa) deserves to be emphasised.
Broadband vibration energy harvesting from a non-deterministic system: Performance of different piezoelectric patch shapes
Authors: Ali Abdelrahman , Muthalif Asan G A , Renno Jamil 
Published: January 2021

Abstract
Harvesting energy from ambient structural vibration using piezoelectric materials gained massive interest in the past decade. Piezoelectric harvesters can be incorporated in many applications; however, one of the main challenges to become widely adopted is to optimize their design for maximum energy harvesting. In this paper, we investigated energy harvesting from a piezoelectric patch that is attached to a non-deterministic thin plate vibrating in bending. Energy harvesting from six patch shapes (differing in the number of edges) was examined through a coupled-field finite element model. The thin plate was simply supported with nominal geometry and material properties. The plate’s dynamics were randomized by randomly distributing point masses on its bottom surface; this made the plate a non-deterministic subsystem. The design optimization was performed by changing the shape of the piezoelectric patch and analyzing the ensemble response of the electrical potential across the piezoelectric patch. The results show that piezoelectric patches with an even number of edges exhibit higher performance in terms of energy harvesting.
Photocatalytic study of Ni-N-codoped TiO2 nanoparticles under visible light irradiation
Authors: Rani Anju , Dhiman R L , Singh Virender , Kumar Suresh , Kumar Suresh 
Published: January 2021

Abstract
In present paper pure and Ni-N-codoped TiO2 nanoparticles have been synthesized via sol gel technique. Crystal phase formation of as synthesized nanoparticles was determined from x-ray diffraction which confirms the existence of anatase phase of TiO2. The average crystalline size was determined from x-ray diffraction and estimated from Transmission Electron Micrographs found to vary from 24.8 nm to 10.2 nm. The morphology was studied by Field Emission Scanning Electron Microscopy and reveals that the synthesized nanoparticles are highly crystalline, spherical and small agglomerated. It is observed that on doping the agglomeration decreases and is due to relative rates of growth process. The band gap energy was calculated from UV–visible absorption spectroscopy and found to be 3.12, 1.81, 1.69 and 1.53 eV respectively. The appearance of emission bands at 453, 470, 483 and 494 nm in Photoluminescence spectra could be arising from defect energy states caused by oxygen vacancies within the forbidden region of TiO2.The structural formation of the synthesized nanoparticles is investigated from Fourier-transform-infrared and Energy dispersive x-ray spectroscopy measurements. Photocatalytic degradation efficiency of as synthesized nanoparticles against two different dyes (Congo red and Methyl orange) was investigated under visible light source of wavelength 420–520 nm and is found to increase with dopant concentration (x). It is observed that the increase in Photocatalytic degradation efficiency of synthesized nanoparticles is attributed to decrease in carrier recombination rate arises from the decrease in band gap energy. On the basis of these observations it is concluded that the increase in Photocatalytic activity is due to increase in surface area arises from the decrease in average crystalline size of the synthesized nanoparticles.
Adverse Histopathologic Characteristics in Small Papillary Renal Cell Carcinomas Have Minimal Impact on Prognosis
Authors: Yang Chen , Shuch Brian , Kluger Harriet M , Serrano Maria , Kibel Adam S , Humphrey Peter A , Adeniran Adebowale J 
Published: January 2021

Abstract

Objectives
Tumor size has long been used in the management decision-making of patients with renal masses. Active surveillance had recently gained traction in selected patients with tumor size of 4 cm or less. Adverse histopathologic characteristics in papillary renal cell carcinoma (PRCC) have been shown to correlate with worse prognosis. We aimed to study whether such features in small PRCCs provide additional prognostic information.

Methods
Nephrectomies from our institution were collected and reviewed to evaluate for adverse histopathologic features. Clinical follow-up information was collected for all cases. Relationships between the variables were examined by Wilcoxon test and logistic regression.

Results
We identified 291 consecutive cases of PRCC. Adverse tumor histopathologic characteristics were significantly related to size. In PRCCs with size greater than 4 cm, there were more cases with high World Health Organization/International Society of Urological Pathology grade and necrosis. Adverse histologic features are less commonly seen in small PRCC and are not associated with lower disease-free survival or disease-specific survival.

Conclusions
Identification of these features in small PRCCs (≤4 cm) through needle core biopsy examination would not provide additional prognostic information in patients for whom active surveillance is considered. Clinical and radiologic follow-up in patients with small renal masses that have a known histologic diagnosis of PRCC should be sufficient.
M2R: a Python add-on to cobrapy for modifying human genome-scale metabolic reconstruction using the gut microbiota models
Authors: Weglarz-Tomczak Ewelina , Tomczak Jakub M. , Brul Stanley 
Published: January 2021

Abstract

Motivation
The gut microbiota is the human body’s largest population of microorganisms that interact with human intestinal cells. They use ingested nutrients for fundamental biological processes and have important impacts on human physiology, immunity and metabolome in the gastrointestinal tract.

Results
Here, we present M2R, a Python add-on to cobrapy that allows incorporating information about the gut microbiota metabolism models to human genome-scale metabolic models (GEMs) like RECON3D. The idea behind the software is to modify the lower bounds of the exchange reactions in the model using aggregated in- and out-fluxes from selected microbes. M2R enables users to quickly and easily modify the pool of the metabolites that enter and leave the GEM, which is particularly important for those looking into an analysis of the metabolic interaction between the gut microbiota and human cells and its dysregulation.

Availability and implementation
M2R is freely available under an MIT License at https://github.com/e-weglarz-tomczak/m2r.

Supplementary information
Supplementary data are available at Bioinformatics online.