bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sobre dificuldades de ingressantes no ensino médio na compreensão de números racionais
Authors: Carvalho Alexia Bezerra de , Guimarães Rita de Cássia da Costa , Vieira William , Pereira Emanoel Fabiano Menezes , Imafuku Roberto Seidi 
Published: March 2021

Apresenta-se, neste artigo, uma análise da resolução de uma questão sobre números racionais, exposta por estudantes ingressantes no Ensino Médio. O objetivo foi identificar as principais dificuldades e erros apresentados pelos participantes sobre o conceito e operações de números racionais. Para isso, realizou-se uma análise de erros das resoluções apresentadas pelos participantes. A interação de aspectos algorítmicos, intuitivos e formais é o referencial teórico adotado nas análises. Verificou-se que os estudantes não possuem clareza sobre o conceito de número racional e apresentam, em decorrência, dificuldades no uso dos procedimentos algorítmicos necessários para a resolução da questão proposta.
Palavras-chave: Números racionais. Análise de erros. Dificuldades. Interpretação.

Difficulties of high school entrants in understanding rational numbers
Abstract
This paper presents an analysis of the resolution of a question about rational numbers, posed by students entering high school. The goal was to identify the main difficulties and errors presented by the participants about the concept and operations of rational numbers. To do so, an error analysis of the resolutions presented by the participants was performed. The interaction of algorithmic, intuitive and formal aspects is the theoretical framework adopted in the analysis. It was found that students do not have clarity about the concept of rational numbers and present, as a result, difficulties in the use of algorithmic procedures necessary to solve the proposed question.
Keywords: Rational numbers. Error analysis. Difficulties. Interpretation.
Penerapan Model Pembelajaran Project Based Learning (PjBL) Untuk Meningkatkan Hasil Belajar Fisika Siswa Kelas XI SMA Negeri 5 Samarinda
Authors: Rante Datu Herlin , Qadar Riskan , M. Junus  
Published: March 2021

Project based Learning (PjBL) adalah model pembelajaran yang melibatkan siswa dalam kegiatan pembelajaran baik dalam merancang ataupun membuat proyek yang berguna untuk memecahkan permasalahan dalam kehidupan sehari-hari. Tujuan dari penelitian ini adalah untuk mengetahui peningkatan hasil belajar siswa setelah diterapkan model PjBL. Jenis penelitian ini menggunakan penelitian kuantitatif dengan motode One Grup-Pretest-posttest. Teknik pengambilan sampel menggunakan purposive sampling dengan sampel yang digunakan adalah siswa kelas XI IPA 6 SMA Negeri 5 Samarinda sebanyak 36 siswa.Teknik pengumpulan data hasil belajar siswa menggunakan teknis tes dengan soal berbentuk essay berjumlah 10 soal. Data hasil belajar siswa sebelum diterapkan model PjBL nilai rata-rata siswa sebesar 20,67 dan setelah diterapkan model PjBL mendapat nilai rata-rata 69,47, dengan demikian terdapat peningkatan hasil belajar yang dilihat dari perolehan nilai N-Gain sebesar 0,51 yang termasuk dalam kategori sedang.
Pengaruh Motivasi, Lingkungan Belajar, Dan Sikap Siswa Terhadap Hasil Belajar Matematika Siswa Kelas VII SMP Negeri 22 Samarinda
Authors: Ningsih Sri , Haryaka Usfandi , Watulingas J. R. 
Published: March 2021

Penelitian ex post facto ini bertujuan untuk mengetahui pengaruh motivasi, lingkungan belajar, dan sikap siswa terhadap hasil belajar matematika siswa kelas VII SMP Negeri 22 Samarinda tahun ajaran 2018/2019. Teknik pengambilan sample adalah simple random sampling. Populasi dalam penelitian ini adalah siswa kelas VII SMP Negeri 22 samarinda yang terdiri dari 9 kelas dengan jumlah 326 siswa, dengan sampel penelitian terdiri dari 5 kelas dengan jumlah 183 siswa. Pengujian hipotesis menggunakan analisis jalur (Path Analysi) dengan taraf signifikansi 5%. Hasil analisis inferensial dengan menggunakan analisis jalur untuk sub-struktur 1 dipeoleh persamaan dengan probabilitas sebesar 0,000, maka sub-struktur 1 signifikan sehingga terdapat pengaruh lingkungan belajar siswa terhadap motivasi siswa dengan kontribusi sebesar 11,42%. Untuk analisis sub-struktur 2 diperoleh persamaan dengan p = 0,000, maka sub-struktur 2 signifikan sehingga terdapat pengaruh motivasi dan lingkungan belajar siswa terhadap sikap siswa dengan kontribusi motivasi sebesar 11,02% dan lingkungan belajar sebesar 5,90%. Untuk analisis sub-struktur 3 diperoleh persamaan dengan p = 0,000, maka substruktur 3 signifikan sehingga terdapat pengaruh motivasi, lingkungan belajar, dan sikap siswa terhadap hasil belajar matematika dengan kontribusi motivasi siswa sebesar 3,61%, lingkungan belajar sebesar 13,54%, dan sikap siswa sebear 2,16%. Dengan demikian terdapat pengaruh motivasi, lingkungan belajar, dan sikap siswa terhadap hasil belajar matematika siswa kelas VII SMP Negeri 22 Samarinda tahun ajaran 2018/2019.
Adaptive system for visualization of the electromagnetic scattering field of aircraft
Authors: Kurbanismailov Z. M. , Tarlanov A. T. , Matyash E. D. , Karbova E. S. 
Published: March 2021

The space industry has always set ambitious tasks to create unique equipment, including control equipment. Ensuring electromagnetic compatibility (EMC) of such systems is carried out at all stages of the life cycle of an aircraft (AC), starting from its development, including testing and stages of operation. Digital technology is characterized by high noise immunity. However, any modern technical system in the aggregate contains sensors, communication lines and receiving antennas sensitive to the effects of external interfering signals that propagate both through wires and over the air. Hence, the relevance of ensuring the EMC of integrated technical systems that perform the functions of measurement, data processing and the formation of control actions, both digital and analog, is obvious. The electromagnetic compatibility of a sophisticated aircraft or spaceship technical system with other systems is a prerequisite for their sustainable operation. Aerospace technology, where both highly sensitive measurements and energetic control effects are closely combined in the dense layout of an aircraft, requires a solution to the EMC problem. This paper shows the need for effective technology to control the electromagnetic radiation created in the surrounding space, both by subsystems of aircraft and by the whole object. A method for visualizing 3D electromagnetic field both in space and in time is considered.
Isolation and identification of different compounds from Citrus assamensis leaf
Authors: Shahriar Mohammad Shahriar , Bhuiyan Mohiuddin Ahmed , Rana Md Sohel 
Published: March 2021

Six coumarins, one benzene, one flavone, one acridone, one limonoid, one triterpene and two phytosterol derivatives were isolated from the methanol, ethanol and chloroform leaf extracts of Citrus assamensis. Extensive spectroscopic studies, including high field 1H NMR and 13C NMR analyses, allowed the identification of thirteen known compounds as bergapten (1), umckalin (2), citropten (3), 4-hydroxybenzaldehyde (4), bergamottin (5), β-amyrin (6), umbeliferone (7), scopoletin (8), citrusinol (9), citracridone-III (10), limonin (11), stigmasterol (12), and β-sitosterol (13). The identity of these compounds was confirmed by comparison with published data as well as co-TLC with authentic samples.
Journal of Bangladesh Academy of Sciences, Vol. 44, No. 2, 85-93, 2020
Versatility of Latissimus Dorsi Free Flap-a Prospective Study
Authors: Islam Abu Faisal Md Ariful , Khan Mohammad Rabiul Karim , Sumi Sharmin Akter , Khan Mohammad Hedayet Ali , Kalam Md Abul 
Published: March 2021

Introduction: Free flaps offer a great variable of available tissues to cover larger, multifocal or multistructural defects. The choice among different free flap is dependent upon their recipient site requirement. Reconstruction with latissimus dorsi flap is now versatile tool in coverage. It can resurface large wound with reliable vascularity, consistent anatomy ,long pedicle length, opportunity for tailoring of flap. It has less donor site morbidity and has very little post-operative complications.
Objective: To evaluate the versatility of free Latissimus dorsi flap for soft tissue reconstruction.
Materials and methods: A prospective, observational study design was used in Department of Plastic Surgery of Dhaka Medical College and Hospital. Here 20 patients with soft tissue defect of variable sizes over lower limb, head neck and trunk underwent coverage with microvascular surgery. The study was carried out from July 2017 to June 2018.
Result: Regarding the age distribution, the mean age was 35.65with an SD of + 10.81. The lowest age was 20years and the highest age was 56 years, Male female ratio was 3:2.The major cause (65.0%) of soft tissue defect of the samples was RTA. The flap was used to reconstruct the soft tissue defect over lower leg in 13 (65%)cases, on scalp 05 (25%) cases and over anterior trunk in two cases. The mean flap dimension was 229.25cm2 and its range was between 120 – 384 cm2. The standard myocutaneous flap was harvested in 80% cases, chimeric (10%) and partial Latissimus muscle flap in two cases. The donor site in all the 20 (100%) cases was closed primarily. The outcome of reconstruction was excellent in 16(80%), good in 02 (10%) cases and poor in 02 (10%) cases. There was no significant complication during the three months postoperative period.
Conclusion: The Latissimus dorsi flap is a versatile option for resurfacing the soft tissue defect in different areas of the body with variable flap components and with minimal donor site morbidity.
J Dhaka Medical College, Vol. 28, No.2, October, 2019, Page 142-152
Efeitos fotobiomoduladores das luzes vermelha, azul e verde sobre o colágeno durante o processo de cicatrização de queimaduras cutâneas: uma revisão integrativa
Authors: Souza Alana Olivia Nascimento de , Catão Maria Helena Chaves de Vasconcelos 
Published: March 2021

Introdução: A cicatrização de feridas é um mecanismo que envolve uma sequência de eventos moleculares com o objetivo de reparo tecidual. Neste sentido, destaca-se o uso fototerapia LED e laser devido as suas características bioestimulantes para a célula durante o processo de reparo. Objetivo: realizar uma revisão de literatura com o intuito de observar o efeito fotobiomodulador das luzes vermelha, azul e verde sobre o colágeno durante o processo de cicatrização de queimaduras. Metodologia: trata-se de uma revisão de literatura do tipo integrativa, realizada nas bases de dados Pubmed, Web of Science e Lilacs. Resultados: entre os 1721 estudos encontrados, somente 18 artigos, publicados entre os anos de 2011 a 2020, foram utilizados dos resultados. Conclusão: A fotobiomodulação das luzes vermelha, azul e verde no processo de reparo de queimaduras cutâneas mostrou resultados satisfatórios principalmente em relação a produção de colágeno, angiogênese, redução da inflamação, redução do tamanho da lesão e estímulo de fibroblastos.
Ectodysplasin A Is Increased in Non-Alcoholic Fatty Liver Disease, But Is Not Associated With Type 2 Diabetes
Authors: Bayliss Jacqueline , Ooi Geraldine J. , De Nardo William , Shah Yazmin Johari Halim , Montgomery Magdalene K. , McLean Catriona , Kemp William , Roberts Stuart K. , Brown Wendy A. , Burton Paul R. , Watt Matthew J. 
Published: March 2021

Ectodysplasin A (EDA) was recently identified as a liver-secreted protein that is increased in the liver and plasma of obese mice and causes skeletal muscle insulin resistance. We assessed if liver and plasma EDA is associated with worsening non-alcoholic fatty liver disease (NAFLD) in obese patients and evaluated plasma EDA as a biomarker for NAFLD. Using a cross-sectional study in a public hospital, patients with a body mass index &gt;30 kg/m2 (n=152) underwent liver biopsy for histopathology assessment and fasting liver EDA mRNA. Fasting plasma EDA levels were also assessed. Non-alcoholic fatty liver (NAFL) was defined as &gt;5% hepatic steatosis and nonalcoholic steatohepatitis (NASH) as NAFLD activity score ≥3. Patients were divided into three groups: No NAFLD (n=45); NAFL (n=65); and NASH (n=42). Liver EDA mRNA was increased in patients with NASH compared with No NAFLD (P=0.05), but not NAFL. Plasma EDA levels were increased in NAFL and NASH compared with No NAFLD (P=0.03). Plasma EDA was related to worsening steatosis (P=0.02) and fibrosis (P=0.04), but not inflammation or hepatocellular ballooning. ROC analysis indicates that plasma EDA is not a reliable biomarker for NAFL or NASH. Plasma EDA was not increased in patients with type 2 diabetes and did not correlate with insulin resistance. Together, we show that plasma EDA is increased in NAFL and NASH, is related to worsening steatosis and fibrosis but is not a reliable biomarker for NASH. Circulating EDA is not associated with insulin resistance in human obesity.Clinical Trial Registrationhttps://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12615000875505, identifier ACTRN12615000875505.
Systematic Assessment of Safety Threshold for Donor Age in Cadaveric Liver Transplantation
Authors: Wang Wenchao , Liu Zhengtao , Qian Junjie , Xu Jun , Que Shuping , Zhuang Li , Geng Lei , Zhou Lin , Zheng Shusen 
Published: March 2021

Background: Donor age affects allograft quality and the prognosis of recipients after liver transplantation (LT). Clinicians have assessed the quality of grafts from older donors based on their appearance and texture, with no reliable quantitative evidence. Our study aimed to assess the quantitative impact of donor age on post-transplant outcomes and its safety threshold for LT, based on the published literature.Methods: Relevant studies were retrieved from the Embase, PubMed, and ISI Web of Science databases. Pooled dichotomous relative risks (RRs) were calculated using metan. Continuous RRs were calculated using a two-stage random-effects model.Results: Eleven studies including 30,691 LT cases were included for further analysis. For categorical comparison, the RR of death within the first post-transplant year was significantly higher among patients who received grafts from older donors. Similarly, the RR of graft failure (GF) was increased within the 3 years after transplantation. For continuous comparison, advanced donor age affected transplant outcomes in a linear manner (P &gt; 0.05). A 10-year increment in donor age was associated with RRs 1.10, 1.12, 1.15, 1.10, and 1.08 for 90-day, 180-day, 1-year, 3-year, and 5-year patient mortality and 1.08, 1.06, 1.10, 1.11, and 1.12, for 90-day, 180-day, 1-year, 2-year, and 3-year GF, respectively (all P &lt; 0.05). A spline model showed that transplants using grafts from donors &lt;43 years old were not associated with age-related risks (P &gt; 0.05). The risk of GF was increased in subgroups with fewer LT cases, longer cold ischemic time, fewer male donors, and recipients with viral hepatitis (P &lt; 0.05).Conclusion: Donor age might affect post-LT outcomes in a dose-dependent manner. The safety threshold for donor age in terms of GF should be lowered to 43 years as an early warning for the guarantee of satisfactory outcomes. Clinicians should weigh the benefits against the risks carefully for patients receiving grafts from older donors. Further studies are warranted to investigate the mechanisms responsible for the relationship between donor age and graft quality.
Effect of Levodopa Initiation on the Gut Microbiota in Parkinson's Disease
Authors: Palacios Natalia , Hannoun Anas , Flahive Julie , Ward Doyle , Goostrey Kelsey , Deb Anindita , Smith Kara M. 
Published: March 2021

Background: The impact of Levodopa on the gut microbiota of Parkinson's disease (PD) patients has not been sufficiently addressed.Methods: We conducted a longitudinal study to examine the impact of Levodopa initiation on the gut microbiota composition of 19 PD patients who had not previously been exposed to Levodopa. Patients provided two stool samples prior to and two samples 90 days after starting Levodopa. Motor impairment (MDS-UPDRS Part III), diet, and other patient characteristics were assessed. 16S rRNA gene amplicon sequencing was used to characterize the microbiota. We examined, cross-sectionally and longitudinally, the associations between Levodopa use and alpha and beta diversity and performed feature-wise, multivariate modeling to identify taxa associated longitudinally with Levodopa use and with improvement in motor function after Levodopa administration.Results: We did not observe significant differences in alpha or beta diversity before vs. after initiation of Levodopa. In longitudinal feature-wise analyses, at the genus level, no taxa were significantly associated with Levodopa use after false discovery rate (FDR) correction (q &lt; 0.05). We observed a marginally lower relative abundance of bacteria belonging to Clostridium group IV in PD patients who experienced a medium or large improvement in motor impairment in response to Levodopa compared to those with a small response [β = −0.64 (SE: 0.18), p-trend: 0.00015 p-FDR: 0.019].Conclusions: In this study, Levodopa was not associated with changes in microbiota composition in this longitudinal analysis. The association between abundance of Clostridium group IV and short-term motor symptom response to Levodopa is preliminary and should be investigated in larger, longer-term studies, that include a control group.
Association Between Circular RNAs and Intracranial Aneurysm Rupture Under the Synergistic Effect of Individual Environmental Factors
Authors: Huang Qing , Sun Yi , Huang Qiuyu , Zeng Yile , Lin Shaowei , Huang Shuna , Cai Yingying , Xu Xingyan , Kang Dezhi , Li Huangyuan , Wu Siying 
Published: March 2021

Introduction: To study the association between specific circular RNAs and rupture of intracranial aneurysm. To explore its clinical diagnostic significance and synergistic effects with individual environmental influencing factors.Methods: Three hundred and forty seven cases and controls were included in this study. Multivariate analysis was used to explore the main individual environmental factors. Intracranial aneurysm rupture related circular RNAs screened based on sequencing was verified in peripheral blood by PCR. ROC curve, logistic regression model and fork analysis were used to study the association, diagnostic values, and synergistic effects of circular RNA with intracranial aneurysms and individual environmental factors.Results: Smoking, hair dyeing, sitting time ≥6 h/day, single animal oil intake and hypertension are the main risk factors for intracranial aneurysm rupture; People with higher education, sleeping time ≥7 h/day, tea drinking, diabetes, higher levels of (hemoglobin, low density lipoprotein, serum calcium, and apolipoprotein-A1) have a low risk of intracranial aneurysm rupture. Hsa_circ_0008433 and hsa_circ_0001946 are closely related to intracranial aneurysm rupture and have certain clinical diagnostic significance (AUC = 0.726; 95% CI: 0.668~0.784). Hsa_circ_0008433 (OR = 0.497, 95% CI: 0.338~0.731), hsa_circ_0001946 (OR = 0.682, 95% CI: 0.509~0.914) were independent epigenetic factors affecting intracranial aneurysm rupture, and have a multiplicative interaction with age (OR = 3.052, 95% CI: 1.006~9.258).Conclusions: Low expressions of hsa_circ_0008433 and hsa_circ_0001946 are risk factors for intracranial aneurysms rupture and have good clinical diagnostic value. There was a multiplicative interaction between epigenetic score and age. The older and the higher the epigenetic score was, the more likely to have intracranial aneurysm rupture.
The Impact of Lockdown During the COVID-19 Outbreak on Dietary Habits in Various Population Groups: A Scoping Review
Authors: Bennett Grace , Young Elysia , Butler Isabel , Coe Shelly 
Published: March 2021

Background: Since the beginning of the COVID-19 pandemic, access to fresh food has been restricted, and people are spending more time inside and have limited their physical activity. However, more time at home may have resulted in some positive habits including an increase in cooking. The aim of this review was to assess dietary changes during the first lockdown. Themes and patterns were considered and associations with other lifestyle factors were assessed.Methods: Between June and July 2020, the PubMed, Google Scholar, and Science Direct databases were searched, and results were screened for eligibility based on title, abstract, and full text. The inclusion criteria of this search included: papers published (or in pre-print) in the year 2020; studies that investigated the impact of COVID-19 lockdown on diet; papers published in English. Exclusion criteria were as follows: papers examining dietary changes in those following a structured diet based on diagnosed conditions or dietetic advice; literature, systematic, or narrative studies reviewing previous research. Researchers agreed on the study characteristics for extraction from final papers.Results: Four thousand three hundred and twenty-two studies were originally considered with 23 final full-text papers included. Four themes were identified: dietary patterns, dietary habits (favorable), dietary habits (unfavorable), and other (includes physical activity levels, weight gain). A total of 10 studies reported an increase in the number of snacks consumed, while six studies found that participants increased their meal number and frequency during quarantine. Eleven studies reported favorable changes in dietary habits with an increase in fresh produce and home cooking and reductions in comfort food and alcohol consumption. However, nine studies found a reduction in fresh produce, with a further six reporting an increase in comfort foods including sweets, fried food, snack foods, and processed foods. Two studies reported an increase in alcohol consumption. In eight studies participants reported weight gain with seven studies reporting a reduction in physical exercise.Conclusion: The effect of COVID-19 lockdown both negatively and positively impacted dietary practices throughout Europe and globally, and negative diet habits were associated with other poor lifestyle outcomes including weight gain, mental health issues, and limited physical activity. Both in the short term and if sustained in the long term, these changes may have significant impacts on the health of the population.