bluuebunny/crossref_metadata_2025_split huggingface dataset:
Extraction of biodiesel from pomelo peel and investigation of its efficiency as a lubricant in water-based drilling fluid
Authors: Sheikh Firoza , Gogoi Bhairab Jyoti 
Published: December 2023

Abstract
Reducing friction between drill string and wellbore wall is one of the key functions of drilling fluid which may result from tight holes, key seats, differential sticking, or cutting build up along the drill string. However due to growing environmental concerns, biodegradable lubricants which are also cost-efficient are appreciated and mandated in many countries. This study discusses the performance analysis of biodegradable biodiesel produced from pomelo peels and Petroleum-based lube oil as drilling fluid lubricants. The test samples comprise 700 mL of water + 10 % bentonite + 3 % barite + 0.25 % CaCO3 + 0.25 % KOH + 1 % CMC + lubricant. Two sets of lubricants were utilized to prepare 10 samples of drilling fluid, one set with petroleum-based lubricant and other with biodiesel. Essential oil was extracted from pomelo peel with the help of the Clevenger apparatus. The oil was then converted to biodiesel through the process of transesterification. Biodiesel properties were tested for the ASTM standards. Both sets of drilling fluid samples were tested for their rheological, filtration and lubricating properties and from the results obtained it can be concluded that both type of lubricating agents have almost negligible impact on rheological and filtration loss properties. However, the lubricity coefficient values drastically decreased as we increased the lubricant content, which is an indication that biodiesel extracted from pomelo peel acts as a better lubricant. The values of the lubricity coefficient for biodiesel based drilling fluid also fell well within the advised range (<0.30). We can therefore draw the conclusion that biodiesel made from pomelo peel can replace petroleum-based lubricants while also lowering the environmental concerns related to lubricants.
Design and control of utility grid-tied bipolar DC microgrid
Authors: Dodda Satish Reddy , Sandepudi Srinivasa Rao 
Published: December 2023

Abstract
This paper explains in detail the design and control of a utility grid-connected bipolar DC microgrid, which consists of a solar photovoltaic system (SPV), a wind energy conversion system (WECS), a battery energy storage system (BESS) at the DC bus, and a three-level neutral point clamped (NPC) converter to connect the DC microgrid to the utility grid. A three-level bidirectional DC–DC converter at the battery energy storage system (BESS) is controlled with model predictive current control (MPCC), and a three-level NPC converter is controlled with a voltage-oriented control based proportional resonant (VOC-PR) controller. The proposed MPCC scheme for the three-level bidirectional DC–DC converter and the VOC-PR control scheme for the three-level NPC converter coordinate with each other to balance and regulate the voltage at the bipolar DC microgrid, control the power flow to the loads at the DC microgrid and the load at the point of common connection (PCC), and also inject or draw power from the utility grid and BESS based on the availability of Renewable Energy Sources (RES). Simulation and experimental results are presented to demonstrate the effectiveness of the proposed MPCC control scheme.
Differential indexing in Kamang: a viewpoint alternation
Authors: Walker Katherine 
Published: December 2023

Abstract
In Kamang (Alor-Pantar, Indonesia), some verbs alternate between indexing the S or P argument with a prefix (from several different series) and occurring unprefixed; that is, Kamang has differential argument indexing. Through a qualitative study of a spoken-language corpus, this paper investigates the alternation between one of the prefix series and zero-marking. Previously described as indicating increased patientivity on intransitive motion and posture verbs, the alternation is here analysed in terms of a shift in event view: unprefixed verbs express events holistically, while prefixed verbs shift the viewpoint towards the “elaboration phase”, the temporal and causal middle and end of an event. Elaboration constructions are associated with resultative and completive semantics and, relatedly, greater affectedness of the undergoer argument. Cross-linguistically, such constructions (e.g., resultatives and middles) are frequently subject to lexical restrictions, and the same applies to the Kamang alternation.
Using photo by-catch data to reliably estimate spotted hyaena densities over time
Authors: Roberts Peter J. , Druce Dave J. , Mgqatsa Nokubonga , Parker Daniel M. 
Published: December 2023

Abstract
Protected areas are becoming increasingly isolated refugia for large carnivores but remain critical for their survival. Spotted hyaenas (Crocuta crocuta) are important members of the African large carnivore guild but, like other members of the guild, routinely come into conflict with people because of their large home ranges that are not always confined to protected areas. To effectively conserve spotted hyaena populations, it is paramount to monitor their abundance through reliable and cost-effective techniques. We estimated the density of spotted hyaenas in Hluhluwe–iMfolozi Park (HiP), South Africa using camera trap images and a spatially explicit capture-recapture (SECR) framework between 2013 and 2018. We estimated an average of 18.29 ± 3.27 spotted hyaenas per 100 km2 between 2013 and 2018, with an annual estimated high of 20.83/100 km2 in 2014 and a low of 11.98/100 km2 in 2015. Our results demonstrate that camera trap by-catch data can be used for estimating spotted hyaena densities over time. We believe that given the widespread use and deployment of camera traps across Africa, collaborative efforts to use existing data to improve regional and continental estimates and population trends for spotted hyaenas should be a priority.
Performance of wrestlers at the Olympic Games: gender aspect
Authors: Curby David , Dokmanac Milorad , Kerimov Fikrat , Tropin Yrui , Latyshev Mykola , Bezkorovainyi Dmytro , Korobeynikov Georgiy 
Published: December 2023

Background and Study Aim. With the increasing popularity of freestyle wrestling, the scientific community is paying more attention to gender factors that may influence the performance and success of competitive activities.
The aim of study to determine differences in performance indicators between male and female wrestlers in the Olympic Games 2021.
Material and Methods. The study included 192 athletes, consisting of 96 male wrestlers and 96 female wrestlers. An analysis of match records and video footage was conducted for women's (n=113) and freestyle (n=114) wrestling at the 2021 Tokyo Olympic Games. The assessment of performance indicators utilized an expert evaluation method. Statistical analysis of the obtained data was carried out using licensed Excel spreadsheet software. For categorical data, results were expressed in absolute numbers and percentages.
Results. Based on the analysis of competitive activities at the 2021 Olympic Games, 12 primary technical-tactical actions were identified. The most frequently employed actions were in the standing position: leg attacks, with male wrestlers performing it 35.8% of the time and female wrestlers 30.3%; in the ground position, male wrestlers employed gut wrench (7.6%), while female wrestlers used ankle lace (9.4%). It was found that male wrestlers and female wrestlers accumulated approximately the same number of points for their actions: male wrestlers (926 points) and female wrestlers (912 points). The effectiveness in the standing position was higher for male wrestlers (720 points) than for female wrestlers (621 points). In the ground positions, female wrestlers demonstrated better effectiveness (291 points) than male wrestlers (206 points). The number of points deducted for rule violations was significantly lower for female wrestlers (8 times) compared to male wrestlers (27 times). Time stoppages during challenge reviews were fewer for female wrestlers (7 times) compared to male wrestlers (18 times).
Conclusions. The conducted research indicates differences in the performance indicators of freestyle wrestling between men and women. Male wrestlers employ more actions in the standing position (81.7%) than female wrestlers (70.7%). Correspondingly, female wrestlers execute more actions in the ground positions (29.3%) compared to male wrestlers (18.3%). The total number of actions performed is higher for male wrestlers (579) than for female wrestlers (518). Female wrestlers achieve more premature victories (32.7% of all matches) compared to male wrestlers (24.6%). The obtained results will assist coaches in better adapting to gender differences and developing specific training programs for athletes.
Improving Students' Mathematical Reasoning Ability and Self-Efficacy Based on DNR-Based Instruction
Authors: Maryono Iyon , Kusumah Yaya Sukjaya , Dahlan Jarnawi A. , Sunandar Sunandar , Jihad Asep 
Published: December 2023

Kemampuan Penalaran Matematis (KPM) dan efikasi-diri sangat penting bagi mahasiswa calon guru matematika. Namun, fakta menjunjukkan bahwa dua hal tersebut belum sesuai dengan harapan. Tujuan penelitian ini adalah untuk menganalisis dampak dari model DNR-based Instructions terhadap KPM dan efikasi-diri mahasiswa. Metode eksperimen semu digunakan pada penelitian ini dengan nonequivalent control group design. Sampel penelitian ini terdiri dari 39 mahasiswa kelompok model DNR-based Instructions dan 39 mahasiswa kelompok model konvensional. Penelitian ini menggunakan instrumen tes-KPM dengan validitas tinggi dan angket efikasi-diri. Hasil penelitian menunjukkan bahwa: KPM mahasiswa kelompok model DNR-based Instructions lebih baik dari pada KPM mahasiswa kelompok model konvensional, ditinjau secara keseluruhan maupun berdasarkan Pengetahuan Awal Matematis (PAM); Efikasi-diri mahasiswa kelompok model DNR-based Instructions berada pada kategori baik. Implikasi dari hasil penelitian ini adalah KPM dan efikasi-diri dapat ditingkatkan melalui aktivitas pembelajaran yang didasarkan pada cara memahami dan cara berpikir, kebutuhan intelektual dan penalaran berulang. Mathematical Reasoning Ability (MRA) and self-efficacy are very important for prospective mathematics teacher students. However, the facts show that these two things have not met expectations. The aim of this research is to analyze the impact of the DNR-based Instructions model on MRA and student self-efficacy. The quasi-experimental method was used in this research with a nonequivalent control group design. The sample for this study consisted of 39 students from the DNR-based Instructions model group and 39 students from the conventional model group. This research has used MRA-test instruments with high validity and self-efficacy questionnaires. The research results show that: MRA for students in the DNR-based Instructions model group is better than MRA for students in the conventional model group, both overall and based on Prior Mathematics Knowledge (PMK); The self-efficacy of students in the DNR-based Instructions model group is in the good category. The implication of the results of this research is that MRA and self-efficacy can be improved through learning activities that are based on ways of understanding and ways of thinking, intellectual needs and repetitive reasoning.
Cognitive Flexibility in Developing Higher-Order Thinking Skills in the Course of Ring Theory
Authors: Nuraida Ida , Sugilar Hamdan 
Published: December 2023

Mata kuliah Teori Ring merupakan salah satu mata kuliah bidang matematika yang cukup ketat dalam memberlakukan sistem deduktif-aksiomatik, namun mahasiswa kesulitan memecahkan masalah karena kurang bisa berpikir secara fleksibel saat menerima informasi baru. Tujuan penelitian ini adalah untuk mengetahui hubungan antara cognitive flexibility dengan keterampilan berpikir tingkat tinggi atau Higher-Order Thinking Skills (HOTS). Metode penelitian yang digunakan adalah korelasional Ex Pose Facto. Penelitian dilakukan di Prodi Pendidikan Matematika UIN Sunan Gunung Djati Bandung dengan jumlah mahasiswa yang diteliti sebanyak 120 orang sebesar 1,2%. Teknik analisis data yang digunakan adalah uji regresi linier sederhana. Berdasarkan hasil penelitian dapat disimpulkan bahwa Cognitive Flexibility memiliki pengaruh positif terhadap kemampuan berpikir tingkat tinggi sebesar . Pengaruh positif ini bermakna semakin meningkatnya Cognitive Flexibility mahasiswa maka akan berpengaruh terhadap peningkatan Kemampuan Berpikir Tingkat Tinggi mahasiswa, sehingga akan memberikan impact pada kemampuan yang dihasilkan dari keterampilan mengerjakan soal HOTS terhadap kemampuan fleksibilitas kognitif yang pada akhirnya terwujud sebuah produk manusia yang siap menghadapi tantangan kompleksitas masalah. The Ring Theory course is one of the mathematics courses that are quite strict in applying deductive-axiomatic systems, but students have difficulty solving problems because they are less able to think flexibly when receiving new information. This study aimed to determine the relationship between cognitive flexibility and Higher-Order Thinking Skills (HOTS). The research method used is correlational Ex Pose Facto. The research was conducted at the Mathematics Education UIN Sunan Gunung Djati Bandung with the number of students studying as many as 120 people amounting to 1.2%. The data analysis technique used is a simple linear regression test. Based on the study results, it can be concluded that Cognitive Flexibility positively influences higher-order thinking skills. This positive influence means that the increasing Cognitive Flexibility of students will affect the improvement of students' higher-order thinking skills, it will have an impact on the abilities resulting from the skills of doing HOTS questions on the ability of cognitive flexibility which ultimately materializes a human product that is ready to face the challenges of problem complexity.
The Development of Problem Solving-Based Interactive Learning Media to Improve Mathematical Communication and Self-Regulated Skill
Authors: Sitanggang Mariani , Mulyono Mulyono , Saragih Sahat 
Published: December 2023

Penelitian ini bertujuan untuk menghasilkan media pembelajaran interaktif valid, praktis, dan efektif yang dikembangkan melalui model Problem Based Learning, menganalisis peningkatan kemampuan komunikasi matematis dan self-regulated learning siswa dengan menggunakan media pembelajaran interakitf model Problem Based Learning, serta menganalisis proses jawaban siswa dalam menyelesaikan tes kemampuan komunikasi matematis. Penelitian ini merupakan penelitian pengembangan dengan menggunakan model 4D (Define, Design, Develop, Disseminate). Subjek penelitian ini adalah siswa kelas 8 SMP. Penelitian ini menghasilkan media pembelajaran interaktif yang berupa RPP, lembar kerja peserta didik, tes kemampuan komunikasi matematis siswa, dan angket self-regulated learning. Hasil penelitian ini menunjukkan bahwa media pembelajaran interaktif yang dikembangkan melalui model Problem Based Learning valid, praktis, dan interaktif, adanya peningkatan kemampuan komunikasi matematis dan self-regulated learning siswa menggunakan media pembelajaran interakitf melalui model Problem Based Learning, serta pada proses jawaban, jenis kesalahan yang sering dilakukan siswa dalam menyelesaikan tes kemampuan komunikasi matematika adalah konsep, operasi perhitungan, dan prinsip. Berdasarkan hasil penelitian ini, peneliti menyarankan agar guru dapat menggunakan perangkat pembelajaran ini guna menumbuhkembangkan kemampuan komunikasi matematis matematis siswa. This research aims to produce valid, practical, and effective interactive learning media developed through the Problem Based Learning model, analyzing the increase in students' mathematical communication skills and self-regulated learning using interactive learning media using the Problem Based Learning model, also analyzing the process of students' answers in solving mathematical communication ability test. This research is development research using the 4D model (Define, Design, Develop, Disseminate). The subjects of this research were class VIII students of junior high school. This research produces interactive learning media in the form of lesson plans, student worksheets, tests of students' mathematical communication skills, and self-regulated learning questionnaires. The results of this research show that the interactive learning media developed through the Problem Based Learning model was valid, practically, and effectively, increased students' mathematical communication skills and self-regulated learning using interactive learning media through the Problem Based Learning model, also in the answer process, the types of errors that students often make in completing mathematical communication ability tests are concepts, calculation operations, and principles. Based on the results of this research, the researcher suggests that teachers can use this learning tool to develop students' mathematical communication skills.
EFICÁCIA DE 24 SEMANAS DE CAMINHADA COM RESTRIÇÃO DO FLUXO SANGUÍNEO NA ATIVAÇÃO E FORÇA MUSCULAR EM IDOSAS COM SOBREPESO E OSTEOPOROSE
Authors: Teixeira Bittar Dra. Simoni , Honorato dos Santos Heleodório , dos Santos Oliveira Leonardo , da Silva Leandro Leonardo , Miranda Machado Ruri , Candido Laurentino Gilberto , Cirilo-Sousa Maria Socorro 
Published: December 2023

O presente estudo objetivou analisar o efeito de 24 semanas de TA com RFS na ativação e força muscular de idosas com excesso de peso e osteopenia/osteoporose. Trinta mulheres idosas [66 (5) anos] foram aleatoriamente designadas para uma das três intervenções: CAM (caminhada de intensidade moderada), CAM+RFS (caminhada de baixa intensidade com RFS) ou RFS (RFS sozinho). A ativação muscular (EMGS) e a força dos flexores e extensores do joelho foram mensuradas, respectivamente, por eletromiografia de superfície e dinamometria, pré-intervenção e após 12 e 24 semanas. O EMGs dos extensores do joelho e a força dos flexores do joelho aumentaram de forma semelhante em todas as intervenções em 24 semanas (p<0,05). Um tamanho de efeito moderado (ES, Cohen’s d) foi observado na EMGs dos extensores do joelho (ES= 0,65) para o CAM+RFS em comparação com o CAM. Os ESs para a força dos flexores do joelho foram −0,86 e −0,69, respectivamente para RFS e CAM+RFS em comparação com CAM. Portanto, as intervenções baseadas no método de RFS apresentaram ganhos de força semelhantes, no entanto, mulheres idosas podem alcançar ganhos neuromusculares de longo prazo ao longo de 24 semanas.
Assessing long-term symptoms in patients with post-pulmonary embolism syndrome using patientreported outcome measures
Authors: Diaconu N. , Sorici G. , Civirjic I. , Grosu A. 
Published: December 2023

People who survive an episode of pulmonary embolism have an increased risk of developing chronic complications despite curative anticoagulant treatment. The association of dyspnoea, low functional capacity, right heart failure, chronic thromboembolic pulmonary hypertension, or chronic thromboembolic pulmonary disease is part of the notion of post-pulmonary embolic syndrome (PPES). The symptoms can be limiting, substantially affecting the quality of life. To improve the overall health outcomes of patients with acute pulmonary embolism, adequate measures to diagnose it and strategies to prevent long-term outcomes of pulmonary embolism are essential.The objective of this study is to provide a definition of PPES and review the most recommended patient-reported outcome measures (PROMs) for assessing the functionality of these patients.We searched PubMed for papers from the last 5 years that contain the terms: postpulmonary embolism syndrome; symptoms; PROMs; score; quality of life; dyspnea. Repetitive publications were excluded. The data from the publications have been summarized in this descriptive overview.
Analysis of outcomes in patients with ST-segment elevation myocardial infarction aged 90 years and older: a single center experience
Authors: Duplyakova P. D. , Pavlova T. V. , Duplyakov D. V. 
Published: December 2023

Aim. To evaluate the effectiveness and safety of an invasive approach in patients with ST-segment elevation myocardial infarction (STEMI) aged 90 years and older.Material and methods. This retrospective single-center study was conducted at the V. P. Polyakov Samara Regional Clinical Cardiology Dispensary. In 20132020, 104 patients aged 90 years and older were hospitalized with a diagnosis of STEMI. The mean age of patients was 91,7 years (90-100), while the proportion of women was 67,3%. Patients included in the analysis were divided into groups of conservative treatment (n=81, mean age, 91,9 (90-100) years, women 70,4%) and invasive management (coronary angiography + percutaneous coronary intervention (PCI)) (n=23, mean age, 91,0 (90-94) years, women, 56,5%).Results. The groups were comparable in basic characteristics. In-hospital mortality in the conservative strategy group was 48,1% vs 17,4% in the invasive management group (p=0,009; odds ratio (OR) 3,35; 95% confidence interval (CI) 1,23-9,15). During the first year after discharge, 25,9% (n=21) died in the conservative strategy group and 30,4% (n=7) in the invasive strategy group (p=0,79; OR 0,85; 95% CI 0,42-1,75). In total (during the hospitalization period and within 1 year after discharge), 60 people (74,1%) died in the conservative strategy group, while in the invasive treatment group — 11 (47,8%) (p=0,02; OR 3,11; 95% CI 1,19-8,11). Life expectancy in patients with STEMI aged 90 years and older after discharge from hospital was 83,95 days for the conservative strategy group and 103,85 days for the invasive strategy group (p=0,67).Conclusion. The data obtained in our study support primary PCI as a treatment strategy for patients with STEMI aged 90 years and older.
Comparative Analysis of Conventional, Sonic and Laser Activated Irrigation Methods on Fracture Resistance of Endodontically Treated Roots: An in vitro Study
Authors: Abdulrahman Shelan , Faraj Bestoon 
Published: December 2023

Objective: To compare the effect of different irrigation activation methods on the fracture strength of endodontically treated roots.
Methods: Sixty extracted single-rooted mandibular premolars with single canals were used. The specimens were instrumented with ProTaper Next rotary instruments up to size X3 and were randomly split into four groups (n=15) according to final irrigation procedures: Group I: Conventional syringe irrigation with distilled water, Group II: Conventional syringe irrigation with NaOCl and EDTA, Group III: Sonic-activated irrigation with EndoActivator and Group IV: Laser-activated irrigation with Er-Cr: YSGG. Using a single-cone technique, root canals were obturated with gutta-percha and AH Plus root canal sealer. All samples were embedded in self-curing acrylic resin and subjected to axial forces by mechanical compression testing in a universal testing machine at 1 mm/min until fracture occurred. The data were evaluated statistically by using analysis of variance (one-way ANOVA) (P < 0.05).
Results: Conventional syringe irrigation with distilled water showed the highest mean value of fracture resistance and Laser-activated irrigation with Er, Cr: YSGG showed the lowest mean value of fracture resistance. In general, statistical analyses showed a non-significant difference between all tested groups (P > 0.05).
Conclusions: The fracture resistance of roots treated endodontically was found to be unaffected by different activation methods. However, Laser-activated irrigation with Er-Cr: YSGG resulted in the greatest reduction of fracture resistance in comparison to the other groups.