bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prolonged Extreme Cold Water Diving and the Acute Stress Response During Military Dive Training
Authors: Kelly Karen R. , Arrington Laura J. , Bernards Jake R. , Jensen Andrew E. 
Published: July 2022

Introduction: Cold water exposure poses a unique physiological challenge to the human body. Normally, water submersion increases activation of parasympathetic tone to induce bradycardia in order to compensate for hemodynamic shifts and reduce oxygen consumption by peripheral tissues. However, elevated stress, such as that which may occur due to prolonged cold exposure, may shift the sympatho-vagal balance towards sympathetic activation which may potentially negate the dive reflex and impact thermoregulation.Objective: To quantify the acute stress response during prolonged extreme cold water diving and to determine the influence of acute stress on thermoregulation.Materials and Methods: Twenty-one (n = 21) subjects tasked with cold water dive training participated. Divers donned standard diving equipment and fully submerged to a depth of ≈20 feet, in a pool chilled to 4°C, for a 9-h training exercise. Pre- and post-training measures included: core and skin temperature; salivary alpha amylase (AA), cortisol (CORT), osteocalcin (OCN), testosterone (TEST) and dehydroepiandosterone (DHEA); body weight; blood glucose, lactate, and ketones.Results: Core, skin, and extremity temperature decreased (p &lt; 0.001) over the 9-h dive; however, core temperature was maintained above the clinical threshold for hypothermia and was not correlated to body size (p = 0.595). There was a significant increase in AA (p &lt; 0.001) and OCN (p = 0.021) and a significant decrease in TEST (p = 0.003) over the duration of the dive. An indirect correlation between changes in cortisol concentrations and changes in foot temperature (ρ = -0.5,p = 0.042) were observed. There was a significant positive correlation between baseline OCN and change in hand temperature (ρ = 0.66, p = 0.044) and significant indirect correlation between changes in OCN concentrations and changes in hand temperature (ρ = -0.59, p = 0.043).Conclusion: These data suggest that long-duration, cold water diving initiates a stress response—as measurable by salivary stress biomarkers—and that peripheral skin temperature decreases over the course of these dives. Cumulatively, these data suggest that there is a relationship between the acute stress response and peripheral thermoregulation.
Potential Role of Pain Catastrophic Thinking in Comorbidity Patients of Depression and Chronic Pain
Authors: Chen Yuanyuan , Ju Peijun , Xia Qingrong , Cheng Peng , Gao Jianliang , Zhang Loufeng , Gao Hua , Cheng Xialong , Yu Tao , Yan Junwei , Wang Qiru , Zhu Cuizhen , Zhang Xulai 
Published: July 2022

BackgroundAlthough comorbidity of major depressive disorder (MDD) and chronic pain (CP) has been well-studied, their association with pain catastrophizing is largely elusive. This study aimed to investigate the potential effects of pain catastrophizing in patients with a comorbidity.MethodsIn total, 140 participants were included in this study and divided into three groups according to the Diagnostic and Statistical Manual of Mental Disorders and the International Association for the study of pain (i.e., the comorbidity group: patients with depression with chronic pain, n = 45; depression group: patients with depression without chronic pain, n = 47; and healthy controls: n = 48). The Hamilton Depression Rating Scale (HAMD)-24 and Hamilton Anxiety Rating Scale (HAMA)-14 were used by professional psychiatrists to evaluate the severity of depression and anxiety. Beck Depression Inventory-II (BDI-II) and Beck Anxiety Inventory (BAI) were conducted by patients' self-report to assess the symptom severity. The pain intensity numerical rating scale (PI-NRS) was used to assess the pain intensity. Pain Catastrophizing Scale (PCS) and Pain Anxiety Symptoms Scale (PASS) were used to estimate pain-related negative thinking.ResultsThe results showed that PASS and PCS scores were significantly different among the three groups. Particularly, the scores in the comorbidity group were the highest. The Pearson correlation analysis revealed a positive correlation between PCS (including the patients' helplessness, magnification, rumination, and total scores) and the severity of depression symptoms, anxiety symptoms, and pain intensity (P &lt; 0.05). A stepwise regression analysis further demonstrated that the total PCS score, high monthly income level, and BDI score had positive impacts on PASS (P &lt; 0.05). We also found that the total BDI score, disease course ≥1 year, and pain intensity had positive effects on PCS (P &lt; 0.05), whereas years of education (≤ 12 years) had a negative effect on PCS (P = 0.012). In all, we have clearly demonstrated that PCS and PASS could serve as potentially predictive factors in patients suffering from comorbidity of MDD and CP.ConclusionOur results suggested that the pain-related catastrophic thinking and anxiety were more severe in the comorbidity group than in MDD-only group and healthy group. Pain-related catastrophizing thoughts and anxiety may have potentially effects on the comorbidity of depression and chronic pain.
Emotional Reactivity in Adolescents With Non-suicidal Self-injury and Its Predictors: A Longitudinal Study
Authors: Kandsperger Stephanie , Schleicher Daniel , Ecker Angelika , Keck Florentina , Bentheimer Sebastian , Brunner Romuald , Jarvers Irina 
Published: July 2022

BackgroundThe management of emergency presentations at child and adolescent psychiatric outpatient clinics, by children and adolescents with self-injurious thoughts and behaviors, represents very responsible tasks but also offers the opportunity for immediate interventions. The stability and degree of emotional reactivity (ER) is a significant psychopathological symptom for development and maintenance of self-injurious behavior, differentiating between those who have continued to injure themselves and those who have not. In general, the relationship between ER and self-injurious behavior has been shown to be bidirectional. However, the stability of ER over time, as well as important predictors for ER itself have not been investigated so far. Therefore, this present study aimed at investigating the stability of ER over time and the relationship between non-suicidal self-injury (NSSI) and ER. Reinforcement functions and several variables of psychological functioning were considered as possible influencing factors.MethodsAs part of a longitudinal study, 97 adolescents aged 11–18 years who presented due to self-injurious thoughts or behaviors underwent standardized emergency management. This included a specified detailed psychiatric assessment at baseline (including the Emotion Reactivity Scale, ERS, and the Self-Injurious Thoughts and Behaviors Interview, SITBI) and treatment recommendations. These were followed by a catamnestic examination with two follow-up appointments. Changes over time in ER, NSSI, reinforcement functions of NSSI and general indicators of psychological functioning (General Severity Index, GSI) were examined and significant correlations were followed up by a linear-mixed effect model predicting the ERS score over time.ResultsData analysis revealed a statistically significant decrease in ERS scores and GSI over time. However, reinforcement functions for and the symptomatology of NSSI did not change. Furthermore, no predictive relationship from ER to NSSI could be identified. A linear-mixed effect model predicting the ERS identified the GSI, automatic positive reinforcement (as a reinforcement function for NSSI) and age as the only significant predictors.ConclusionResults demonstrate the importance of NSSI reinforcement functions for heightened emotional reactivity and emphasize their role as a point for therapeutic intervention by providing alternatives to NSSI and thereby possibly reducing emotional reactivity.
The Longitudinal Relationship Between eHealth Literacy, Health-Promoting Lifestyles, and Health-Related Quality of Life Among College Students: A Cross-Lagged Analysis
Authors: Li Shaojie , Cui Guanghui , Zhou Feixiang , Liu Siyue , Guo Yicong , Yin Yongtian , Xu Huilan 
Published: July 2022

ObjectivesThis study aimed to explore the longitudinal associations between eHealth literacy, health-promoting lifestyles, and health-related quality of life (HRQoL) among college students.MethodsFrom December 2019 (T1) to December 2020 (T2), we administered the eHealth literacy scale, Short-Form Health Survey (SF-12), and Short-Form Health-Promoting Lifestyle Profile Scale to 1,181 college students in Jinan, China. Participants were recruited for 12 months for the two-stage survey.ResultsStable positive correlations were shown between eHealth literacy, health-promoting lifestyles, and HRQoL across time. The cross-lagged analysis showed that eHealth literacy at T1 predicted health-promoting lifestyles at T2 (β = 0.080, P = 0.006); however, health-promoting lifestyles at T1 did not predict eHealth literacy at T2 (β = −0.026, P = 0.499). HRQoL at T1 predicted health-promoting lifestyles at T2 (β = 0.147, P &lt; 0.001); however, similar to the eHealth literacy finding, health-promoting lifestyles at T1 did not predict HRQoL at T2 (β = 0.045, P = 0.142). eHealth literacy was also bi-directionally associated with HRQoL, and the prediction effect of eHealth literacy at T1 to HRQoL at T2 (β = 0.078, P = 0.008) was slightly higher than the prediction effect of HRQoL at T1 to eHealth literacy at T2 (β = 0.074, P = 0.023).ConclusioneHealth literacy and HRQoL may be antecedents for college students' health-promoting lifestyles. There may be significant bi-directional relationships between eHealth literacy and HRQoL.
Pengaruh Lama Fermentasi terhadap Kadar Etanol dari Limbah Serabut Kelapa Sawit Hasil Pretreatment Alkali dan Hidrolisis Asam
Authors: Hasanah Nurul , Side Sumiati , Sudding Sudding 
Published: July 2022

ABSTRAKSerabut kelapa sawit merupakan sumber lignoselulosa yang belum termanfaatkan secara optimal dan dapat dijadikan sebagai bahan baku pembuatan etanol. Penelitian ini bertujuan untuk mengetahui pengaruh lama fermentasi terhadap kadar etanol yang dapat dihasilkan dari fermentasi serabut kelapa sawit. Penelitian ini diawali dengan pembersihan dan pengecilan ukuran serabut kelapa sawit. Kemudian pretreatment menggunakan NaOH 4%, hidrolisis dengan H2SO4 2% dan penentuan kadar gula reduksi menggunakan metode Luff Schoorl. Hasil hidrolisis kemudian difermentasi menggunakan ragi tape dengan variasi waktu fermentasi 1, 2, 3, 4, 5, 6, dan 7 hari. Pengukuran kadar etanol dilakukan dengan menghitung densitas etanol dari hasil fermentasi yang telah didestilasi. Hasil penelitian menunjukkan bahwa serabut kelapa sawit dengan kadar gula reduksi sebesar 1,95% memiliki kadar etanol tertinggi pada fermentasi 5 hari dengan kadar etanol sebesar 5,96% dan densitas 0,98513 g/mL.Kata kunci: Serabut kelapa sawit, Lignoselulosa, Ragi Tape, Fermentasi, Etanol ABSTRACTPalm-press fibers is a source of lignocellulose that has not been utilize optimally and can be used as raw material for produce ethanol. This research aims to determine the effect of fermentation periode to ethanol concentration that can be produced from palm-press fibers fermentation. This research begins with the preparation that includes cleaning and size reduction of palm-press fibers. Then pretreatment using NaOH 4%, hydrolysis using H 2SO 4 2%, and determination of reducing sugar id done by Luff Schoorl method. Then fermented using tape yeast with fermentation time variation of 1, 2, 3, 4, 5, 6, and 7 days. Ethanol content measurement is performed by calculating the density of ethanol from the fermentation that has been distilled. The results showed that palm-press fibers with 1,95% reducing sugar has the highest ethanol content obtained in the fermentation of 5 days with the resulting ethanol content was 5.96% and the density of 0.98513 g/mL.Keywords: Palm-press Fibers, Lignocellulose, Tape Yeast, Fermentation, Ethanol
Isolasi dan Identifikasi Senyawa Metabolit Sekunder Ekstrak n-heksana Tumbuhan Meniran (Phyllanthus niruri Linn.)
Authors: Risnawati Risnawati , Muharram Muharram , Jusniar Jusniar 
Published: July 2022

ABSTRAKPenelitian ini adalah penelitian eksplorasi yang bertujuan untuk mengisolasi dan mengidentifikasi senyawa metabolit sekunder ekstrak n-heksana dari tumbuhan Meniran. Penelitian ini dilakukan melalui beberapa tahap, diantaranya preparasi, ektraksi dengan metode maserasi, partisi, fraksinasi, pemurnian, dan identifikasi. Hasil penelitian berupa dua senyawa kristal putih berbentuk jarum. Senyawa A positif terhadap pereaksi FeCl3 dan senyawa B positif terhadap pereakasi Lieburmann-Buchard. Berdasarkan hasil uji pereaksi dan data FTIR dan UV-Vis, menunjukkan bahwa senyawa A adalah Flavonoid dan senyawa B adalah terpenoid. Kata kunci: Isolasi, P. niruri Linn., Flavonoid dan Terpenoid ABSTRACTThis study is exploratory research that aim to isolate and identify the secondary metabolite compound of n-hexane extract of Meniran plant. This research was carried out in several steps; they were preparation, extraction of sample with maceration, partition, fractionation, purification and identification. The result were two needle white crystal. Compound A positive to FeCl3 reagent, while compound B positive to Liebermann-Burchard reagent. Base on the reagent test and FTIR and UV-Vis data, showed that the compound A is flavonoid and compound B is terpenoid. Keyword: Isolation, P. niruri Linn., Flavonoid and Terpenoid
Kandungan Fenolik Total Ekstrak Etanol Dan Etil Asetat Buah Mengkudu (Morinda citrifolia, L.) Serta Uji Bioaktivitas Terhadap Bakteri Escherichia coli
Authors: Sari Trianita , Maryono Maryono , Hasri Hasri , Abbas Gusma Harfiana 
Published: July 2022

ABSTRAK Penelitian ini bertujuan untuk mengetahui kandungan fenolik total dari ekstrak etanol dan etil asetat buah mengkudu (Morinda Citrifolia, L) dan aktivitas antibakteri tehadap bakteri Escherichia coli. Ekstrak Buah mengkudu yang telah di evaporasi dilakukan analisa senyawa dengan menggunakanspektrofotometer UV untuk mengetahui kandungan total senyawa fenol. Dan ekstrak buah mengkudu di uji bioaktivitas terhadap bakteri Escherichia coli. Dari hasil penelitian didapat kadar fenol ekstrak etanol sebesar 171,91 mg/L dan pada ekstrak etil asetat 23,27 mg/L. Dan Aktivitas antibakteri ekstrak etanol buah mengkudu dan ekstrak etil asetat buah mengkudu dapat mengahambat bakteri Escherichia coli. Kata Kunci: Antibakteri, Buah mengkudu, fenolik total ABSTRACT This research aims to determine the ability of ZnO-Zeolite to degrade Acid Orange 7. The first, synthesized zinc acetate precursors from Zn waste batteries. Next, synthesized ZnO from the precursor of zinc acetate and impregnated with zeolite to form a ZnO-Zeolite composite used the sol-gel method. Photodegradation test for Acid Orange 7 dye used a concentration of 50 ppm with variations in pH 3, 5, 7, 9 and 11. Measurement of concentration of Acid Orange 7 dye degradation results used a UV-Vis Spectrophotometer at a wavelength of 484.45 nm. The results showed that ZnO-Zeolite composites were able to degrade Acid Orange 7 dyes at pH 7 with a degradation percentage of 94.15%. Keywords: ZnO-Zeolite composite, acid orange 7, degradation
Penentuan pH Optimum Gel Metasilikat Sekam Padi sebagai Media Tumbuh Kristal Tunggal Kalsium Tartrat Tetrahidrat (CaC4H4O6.4H2O)
Authors: Putri Suriati Eka , Hasri Hasri , Ramdani Ramdani , Yunanda Yunanda 
Published: July 2022

ABSTRAKPenelitian ini bertujuan untuk mengetahui pH optimum sintesis gel metasilikat sekam padi sebagai media tumbuh kristal tunggal kalsium tartrat tetrahidrat (CaTT). Tahapan penelitian ini meliputi preparasi sampel, pembentukan gel metasilikat, sintesis kristal CaTT dan karakterisasi gel metasilikat. Abu sekam padi yang digunakan mengandung SiO2 sebesar 98,45% berpotensi untuk membentuk filtrat natrium silikat (Na2SiO3). Filtrat natrium silikat direaksikan dengan asam tartrat (C4H6O6) menghasilkan gel metasilikat pada pH 5,00; 5,25; 5,50; 5,75 dan 6,00. Supernatan kalsium klorida (CaCl­2) berdifusi ke dalam gel membentuk kristal CaTT berwarna putih jernih sebanyak 0,2649 g pada pH optimum 5,25. Analisis gugus fungsi gel metasilikat menggunakan spektroskopi FTIR memberikan serapan yang khas untuk gugus fungsi –OH pada 3400,05 cm-1 dan 920,05 cm-1, gugus fungsi C=O pada 1622,13 cm-1 dan C-O pada 1346,31 cm-1, serta gugus Si-O-Si pada 1064,71 cm-1. Karakterisasi gel metasilikat menggunakan XRD mengindikasikan bahwa struktur gel metasilikat hasil sintesis tersusun atas garam Na2C4H4O6.2H2O, senyawa SiO2 dan C-grafit. Berdasarkan analisis gugus fungsi menggunakan FTIR dan karakterisasi menggunakan XRD, dapat disimpulkan bahwa sekam padi berpotensi untuk dijadikan gel metasilikat sebagai media tumbuh kristal tunggal CaTT.Kata kunci: Sekam padi, Natrium Silikat, Gel metasilikat, Kalsium tartrat tetrahidrat
Pengaruh Konsentrasi Natrium Hidroksida (NaOH) Dalam Sintesis Nanosilika Dari Tongkol Jagung dengan Metode Kopresipitasi
Authors: Renika Desi , Wijaya Mohammad , Pratiwi Diana Eka 
Published: July 2022

ABSTRAKPenelitian ini bertujuan untuk mengetahui pengaruh konsentrasi NaOH terhadap ukuran nanosilika dan untuk mengetahui konsentrasi NaOH optimum yang digunakan dalam sintesis nanosilika dengan metode kopresipitasi. Sintesis nanosilika menggunakan variasi konsentrasi NaOH 1 M, 2 M, 3 M, 4 M, 5 M. Selanjutnya setelah memperoleh nanosilika, melakukan analisis kandungan silika menggunakan XRF, menentukan ukuran partikelnya menggunakan XRD, dan karakterisasi morfologi menggunakan SEM. Hasil sintesis nanosilika mengandung unsur silika (SiO2) berturut turut 98,01 %, 97,04 %, 95,60 %, 96,70% dan 96,66 % dan ukuran partikel berturut turut adalah 23,13 nm, 20,96 nm, 15,43 nm 14,74 nm, dan 19,80 nm. Morfologi nanosilika memiliki rongga dan bentuk partikel tidak homogen.Kata kunci : Tongkol Jagung, Konsentrasi, Kopresipitasi, dan Nanosilika.ABSTRACTThis study aims to discover the effect of NaOH concentration on the size of nanosilica and to discover the optimum NaOH concentration was used in synthesis of nanosilica with coprecipitation method. Synthesis of nanosilica used variations of NaOH concentration 1 M, 2 M, 3 M, 4 M and 5 M. Furthermore, after obtained nanosilica, analyzed its silica content by XRF, determined its particle sized by XRD and characterizes its morphology by SEM. The results of synthesis of nanosilica contained silica element (SiO2) in a row are 98.01%, 97.04%, 95.60%, 96.70% and 96.66% and the particle sized in a row are 23.13 nm, 20.96 nm, 15.43 nm, 14.74 nm and 19.80 nm.The nanosilica morphology had cavities and its particle shape is not homogeneous.Keywords: Corn Cob, Concentration, Coprecipitation, and Nanosilica
Pengaruh Model Problem Based Learning terhadap Hasil Belajar Peserta Didik Kelas XI MIA SMAN 2 Makassar (Studi Pada Materi Pokok Laju Reaksi)
Authors: Sandabunga’ Selni , Anwar Muhammad , Alimin Alimin 
Published: July 2022

ABSTRAKPenelitian ini adalah penelitian eksperimen semu yang bertujuan untuk mengetahui pengaruh model problem based learning terhadap hasil belajar peserta didik kelas XI MIA SMAN 2 Makassar pada materi pokok laju reaksi. Variabel bebas dalam penelitian ini adalah model problem based learning dan model pembelajaran langsung. Variabel terikatnya hasil belajar peserta didik pada materi pokok laju reaksi. Populasi penelitian ini adalah peserta didik kelas XI MIA SMAN 2 Makassar yang terdiri dari delapan kelas. Teknik pengambilan sampel yaitu simple random sampling. Sampel penelitian terdiri dari dua kelas yaitu kelas XI MIA 7 sebagai kelompok eksperimen dan kelas XI MIA 8 sebagai kelompok kontrol dengan jumlah peserta didik masing-masing sebanyak 34 orang. Hasil analisis deskriptif menunjukkan nilai rata-rata hasil belajar kelas eksperimen sebesar 83,21 dan kelas kontrol sebesar 78,28 dengan standar deviasi berturut-turut adalah 8,09 dan 7,42 dengan ketuntasan hasil belajar peserta didik sebesar 85,29% untuk kelas eksperimen dan 50,00% untuk kelas kontrol. Hasil pengujian hipotesis dengan uji-t pada taraf signifikan, α = 0,05 diperoleh nilai thitung (2,65) > ttabel (1,67) menunjukkan hipotesis diterima. Model problem based learning berpengaruh terhadap hasil belajar peserta didik kelas XI MIA SMAN 2 Makassar pada materi pokok laju reaksi.Kata Kunci: model problem based learning, hasil belajar, laju reaksi ABSTRACTThis research was a quasi-experimental that aimed to know the effect of problem based learning model toward student learning outcome in XI MIA class of SMAN 2 Makassar on subject matter of reaction rate. The independent variables are the problem based learning and direct learning model while the dependent variable was the student’s learning outcome on reaction rate subject matter. The population was XI MIA class of SMAN 2 Makassar consisted of two classes, namely XI MIA 7 class as an experiment group and XI MIA 8 class as a control group with 34 students in each classes. Sampling technique was a simple random sampling, that the results of descriptive analyzed showed that the average of experimental class is 83,21 and control class is 78,28 with standard deviation are 8,09 and 7,42 while completeness is 85,29% for experimental class and 50,00% for control class. The results of hypothesis testing using t-test at significance level of α = 0,05 obtained that tcalculated = 2,65 > ttable = 1,67, there is an effect of Problem Based Learning Model Toward Student Learning Outcomes in class XI MIA SMAN 2 Makassar with subject matter of reaction rate.Keyword: problem based learning model, student learning outcome, reaction rate.
Review: Penggunaan Katalis Heterogen pada Produksi Biodiesel
Authors: Abbas Gusma Harfiana , Ilyas Nita Magfirah 
Published: July 2022

ABSTRAKBiodiesel merupakan bahan bakar alternatif yang telah menjadi bahan penelitian yang menarik saat ini karena bersifat ramah lingkungan dan dianggap sebagai bahan bakar alternatif yang tepat untuk masa depan dimana biodiesel terbuat dari sumber biologis terbarukan seperti minyak nabati dan lemak hewani. Biodiesel dapat diproduksi melalui reaksi transesterifikasi ataupun esterifikasi dimana minyak atau lemak direaksikan dengan alkohol monohidrat dengan bantuan katalis. Proses transesterifikasi dipengaruhi oleh cara reaksi, rasio molar alkohol terhadap minyak, jenis alkohol, sifat dan jumlah katalis, waktu reaksi, dan suhu. Berbagai penelitian telah dilakukan dengan menggunakan minyak yang berbeda sebagai bahan baku dan alkohol yang berbeda (metanol, etanol, butanol), serta katalis yang berbeda. Penelitian terbaru saat ini berfokus pada aplikasi katalis heterogen untuk menghasilkan biodiesel, karena bersifat ramah lingkungan dan lebih ekonomis. Jurnal ini membahas literatur mengenai produksi biodiesel baik katalitik maupun nonkatalitik serta keuntungan dan kerugian dari berbagai metode dan katalis yang digunakan. Kata Kunci: Biodiesel, Katalis, Katalis Heterogen