bluuebunny/crossref_metadata_2025 huggingface dataset:
Двухканальный электронный транспорт в подвешенных квантовых точечных контактах с боковыми затворами
Authors: Похабов Д.А. , Погосов А.Г. , Жданов Е.Ю. , Бакаров А.К. , Шкляев А.А.
Published: September 2020

The conductance of a suspended quantum point contact fabricated from GaAs/AlGaAs heterostructures with a two-dimensional electron gas, equipped with the in-plane side gates separated from the constriction using lithographical trenches, is studied. The conductance as a function of the gate voltages demonstrates unusual double-channel regime with independent channel’s conductance quantization: two side gates can drive the conductance of the separate channels independently. A possible electrostatic mechanism of the double-channel structure formation inside a single constriction is connected with the lateral redistribution of the low-mobility X-valley electrons contained in superlattice layers, resulting in the emergence of the potential barrier in the middle of quantum point contact, separating the conducting electrons into two channels, symmetrically shifted towards the lithographical trenches, defining the nanostructure geometry.
Структурные, электрические и оптические свойства 4H-SiC для ультрафиолетовых фотоприемников
Authors: Калинина Е.В. , Каташев А.А. , Виолина Г.Н. , Стрельчук А.М. , Никитина И.П. , Иванова Е.В. , Забродский В.В.
Published: September 2020

Представлены результаты исследования различными методиками исходных структур n-4H-SiC, представляющих высоколегированную n+-подложку с выращенным химическим осаждением из газовой фазы эпитаксиальным слоем толщиной 5 мкм. Концентрация носителей заряда в эпитаксиальном слое в диапазоне Nd-Na=(1-50)·1014 см-3. Привлекая результаты рентгеноструктурного анализа, было установлено, что для получения эффективных 4H-SiC ультрафиолетовых фотоприемников желательно иметь структуры эпитаксиальных слоев, в которых наблюдается эффект геттерирования точечных дефектов, что приводит к росту времени жизни носителей заряда и увеличению значений квантовой эффективности. Фоточувствительность исследованных образцов значительно зависит от степени дефектности в CVD эпитаксиальном слое, приводящей к изменению времени жизни носителей заряда и, как следствие, к изменению квантовой эффективности 4H-SiC ультрафиолетовых фотоприемников. Ключевые слова: карбид кремния, рентгеноструктурный анализ, эффект геттерирования, квантовая эффективность.
Структура, соcтав и свойства кремния, имплантированного ионами цинка и кислорода при повышенной температуре
Authors: Привезенцев В.В. , Сергеев А.П. , Куликаускас В.С. , Киселев Д.А. , Трифонов А.Ю. , Терещенко А.Н.
Published: September 2020

The Czochralski growth Si (100) substrates were implantation by 64Zn+ ions with dose of 5×10^16 cm−2 and energy of 50 keV and then by the 16O+ ions with dose of 2×10^17 cm−2 and energy of 20 keV. During implantation the substrate temperature was about 350◦C. Then, the substrates were cut into 10×10mm samples, and were subjected to isochronous (for 20min) photonic annealing in vacuum. At each stage of photon annealing, the effective temperature was varied from 500 up to 900◦C with a step of 100◦C. After implantation the radiation-induced point defects and their clusters are formed in the subsurface layer, twin grains, dislocations, as well as Zn-containing clusters (mainly of Zn and ZnO composition) with an average size of 10−20nm and an average size of 20−50 nm on Si substrate surface. As the annealing proceeds, the radiation defects gradually disappear, and after annealing at an effective temperature of 700◦C
the Zn-containing clusters (presumably consisted of ZnO phase
and particularly of Zn2SiO4 phase) with a size of about 100 nm
are revealed in the surface layer and on the Si substrate surface.
Метод трансляционного переноса для оценки стабильности нестационарного квантового стандарта частоты
Authors: Божокин С.В. , Баранцев К.А. , Литвинов А.Н.
Published: September 2020

Continuous wavelet transform is used to analyze the operation of a non-stationary signal of a quantum frequency standard. The method of translational transfer is proposed, with the help of which the boundary phenomena in this transformation are eliminated. The spectral integrals of the quantum frequency standard signal in various frequency ranges are calculated. A wavelet dispersion is introduced, which makes it possible to determine the moments of time when the signal fluctuations are the strongest. The comparison of the wavelet variance with the usual variance and with the Allen variance is carried out.
О распределении по размерам дисперсных частиц фрактальной формы
Authors: Федосеев В.Б. , Шишулин А.В.
Published: September 2020

In this paper, a dispersed system formed by an ensemble of particles of different volume has been modeled in the framework of a thermodynamical approach. Particle shape has been determined by its fractal dimension which correlates its volume and surface area. Using the methods of number theory and Hardy-Ramanujan-Rademacher formula, we have calculated the equilibrium size distributions for nanoparticles of different shape in an ensemble. Estimates of the average volume and fractal dimension of dispersed particles have been obtained based on distribution functions. The correlation between average geometrical characteristics of particles in the ensemble, thermodynamical conditions of the dispersed system and properties of its substance have also been revealed.
Механические свойства поверхностных Ti-Ni-Ta- и Ti-Ni-Ta-Si-сплавов, синтезированных на подложках из никелида титана
Authors: Дьяченко Ф.А. , Мейснер Л.Л. , Шугуров А.Р. , Нейман А.А. , Семин В.О. , Атовуллаева А.А.
Published: September 2020

The physical-mechanical properties of Ti-Ni-Ta and Ti-Ni-Ta-Si-based surface alloys of ~1 μm thickness synthesized on the NiTi substrates by the additive thin-film electron beam method were investigated. The effect of these surface alloys on the functional properties of the composite systems [Ti-Ni-Ta surface alloy/TiNi substrate] and [Ti-Ni-Ta-Si surface alloy/TiNi substrate] was explored. It was established that Ti-Ni-Ta-Si based surface alloy with an amorphous structure is characterized by higher gradients of hardness and Young’s modulus in comparison with Ti-Ni-Ta based surface alloy, and has an increased by ~10% and ~2 times greater plasticity compared to the initial NiTi substrate and the Ti-Ni-Ta based surface alloy, respectively. Evaluation of the shape memory effect and superelasticity of the composite systems [Ti-Ni-Ta surface alloy/TiNi substrate] and [Ti-Ni-Ta-Si surface alloy/TiNi substrate] has shown that synthesis of the surface alloy with an amorphous structure results in an almost 2-fold increase in the martensitic shear stress and a significant decrease in the stress hysteresis width compared with the untreated TiNi samples.
Двухфазность кристаллической структуры твердых растворов (1-x)PbFe-=SUB=-2/3-=/SUB=-W-=SUB=-1/3-=/SUB=-O-=SUB=-3-=/SUB=--xPbTiO-=SUB=-3-=/SUB=- (x=0.25,0.3,0.35) при комнатной температуре
Authors: Зайцева Н.В. , Набережнов А.А. , Смирнова Е.П.
Published: September 2020

The evolution of the crystal structure of (1-x) PbFe2 / 3W1 / 3O3 - хPbTiO3 solid solutions depending on the PbTiO3concentrations (at x = 0.25, 0.3, 0.35) in the region of the morphotropic phase boundary was studied using x-ray diffraction at room temperature. It was established that all three compositions are a mixture of cubic and tetragonal phases, and an increase in the concentration of PbTiO3 above 30 mol. % leads to an increase of the tetragonal phase contribution. The parameters of the crystal structure and the content of both phases in these solid solutions are determined. It was shown that at room temperature there are static displacements of lead ions from the principle crystallographic positions.
Квазистационарное приближение в задаче возбуждения низкочастотных электромагнитных полей в литосфере
Authors: Терещенко Е.Д. , Терещенко П.Е.
Published: September 2020

The paper considers the excitation of a horizontal grounded antenna of the ELF-ELF electromagnetic field and a lower frequency range in a two-layer environment. Approximate analytical formulas are obtained that describe quite completely behavior of fields in the low-frequency range. The accuracy of using the quasi-stationary approximation is analyzed. The possibility of replacing the actual surface impedance with a plane wave impedance, normally falling on the interface. For a number of experiments carried out on the Kola Peninsula in the framework of the international cooperation (FENICS-2014, FENICS-2019), the frequency boundaries of the applicability of the approximate approach in assessing conductivity of the Earth.
Влияние допирования атомами N, Вr и F на электродинамические характеристики и физические свойства изатин-beta-анила
Authors: Гусев А.Н. , Мазинов А.С. , Тютюник А.С. , Фитаев И.Ш. , Гурченко В.С. , Брага Е.В
Published: September 2020

Рассмотрено взаимодействие электромагнитного излучения 250--850 nm, 2.5-15.3 μm и 11.5-17.1 mm с пленками на основе изатин-beta-анил C14H10N2O, осажденными методом полива из раствора. Показано, что модификация исходной структуры атомами N, Br и F приводит к девиации частоты и изменению амплитуды люминесценции, а также к изменению частотных зависимостей коэффициентов поглощения относительно исходного изатин-beta-анила. Ключевые слова: органические тонкие пленки, электромагнитное излучение, изатин, СВЧ, оптический спектр, люминесценция, рентгенофазовый анализ.
Исследование влияния пространственного заряда на транспортировку 2 MeV пучка протонов в ускорительном источнике эпитепловых нейтронов
Authors: Быков Т.А. , Касатов Д.А. , Колесников Я.А. , Кошкарев А.М. , Макаров А.Н. , Остреинов Г.М. , Соколова Е.О. , Таскаев С.Ю. , Щудло И.М.
Published: September 2020

A neutron source comprised of a vacuum insulated tandem accelerator and a solid lithium target is in operation for development of boron neutron capture therapy and other applications. The size of the proton beam on the target surface depending on the proton beam current was measured using an infrared camera and thermocouples inserted inside the target. The absence of a noticeable influence of the space charge on the transportation of the proton beam from the accelerator to the target at a distance of 5 m has been established, which simplifies the operation of the neutron source.
Траекторный анализ в коллекторе с многоступенчатой рекуперацией энергии для прототипа гиротрона DEMO. Часть I. Идеализированное распределение магнитного поля
Authors: Лукша О.И. , Трофимов П.А. , Мануилов В.Н. , Глявин М.Ю.
Published: September 2020

The results of modeling of collector for the gyrotron prototype being developed for the DEMO project are presented. A trajectory analysis in a collector with a 4-stage recovery of the residual beam energy based on the method of spatial separation of electrons in crossed azimuthal magnetic and axial electric fields was performed. In this part of the study, the formation of the azimuthal magnetic field was carried out using a conductor located on the axis of the device. The study was performed for a spent electron beam with a velocity and coordinate distribution of particles close to those obtained in experiments with powerful gyrotrons. Due to a thorough choice of the geometry of the collector sections, a total gyrotron efficiency of more than 80% was achieved, which is close to maximum efficiency with perfect separation of fractions of an electron beam with different energies. The data obtained will be used for development of a toroidal solenoid designed to create an azimuthal magnetic field.
Синтез и исследование нанопорошков и керамики магний-алюминиевой шпинели, активированной медью
Authors: Осипов В.В. , Соломонов В.И. , Подкин А.В. , Шитов В.А. , Тихонов Е.В. , Корсаков А.С.
Published: September 2020

Методом лазерного испарения твердой мишени, представляющей собой механическую смесь простых оксидов (MgO, Al2O3, CuO), получены нанопорошки, представленные двумя кристаллическими фазами: магний-алюминиевая шпинель (98 wt.%) и куприт (2 wt.%). Из этих нанопорошков изготовлены пробные образцы прозрачной керамики Cu:MgAl2O4, в ИК спектрах пропускания которых обнаружены две новые сильные полосы поглощения при λ1~1.55 (1.45) и λ2~3.45 (3.03) μm, соответствующие переходам между штарковскими уровнями 2E(t62e3) и 2T2(t52e4) ионов Cu2+ в октаэдрической и тетраэдрической позициях соответственно. Ключевые слова: магний-алюминиевая шинель, ион меди, нанопорошок, керамика, ИК спектр пропускания, полосы поглощения иона меди.
Artificial Intelligence and Its Effect on Dermatologists’ Accuracy in Dermoscopic Melanoma Image Classification: Web-Based Survey Study (Preprint)
Authors: Maron Roman C , Utikal Jochen S , Hekler Achim , Hauschild Axel , Sattler Elke , Sondermann Wiebke , Haferkamp Sebastian , Schilling Bastian , Heppt Markus V , Jansen Philipp , Reinholz Markus , Franklin Cindy , Schmitt Laurenz , Hartmann Daniela , Krieghoff-Henning Eva , Schmitt Max , Weichenthal Michael , von Kalle Christof , Fröhling Stefan , Brinker Titus J
Published: September 2020

BACKGROUND

Early detection of melanoma can be lifesaving but this remains a challenge. Recent diagnostic studies have revealed the superiority of artificial intelligence (AI) in classifying dermoscopic images of melanoma and nevi, concluding that these algorithms should assist a dermatologist’s diagnoses.

OBJECTIVE

The aim of this study was to investigate whether AI support improves the accuracy and overall diagnostic performance of dermatologists in the dichotomous image–based discrimination between melanoma and nevus.

METHODS

Twelve board-certified dermatologists were presented disjoint sets of 100 unique dermoscopic images of melanomas and nevi (total of 1200 unique images), and they had to classify the images based on personal experience alone (part I) and with the support of a trained convolutional neural network (CNN, part II). Additionally, dermatologists were asked to rate their confidence in their final decision for each image.

RESULTS

While the mean specificity of the dermatologists based on personal experience alone remained almost unchanged (70.6% vs 72.4%; P=.54) with AI support, the mean sensitivity and mean accuracy increased significantly (59.4% vs 74.6%; P=.003 and 65.0% vs 73.6%; P=.002, respectively) with AI support. Out of the 10% (10/94; 95% CI 8.4%-11.8%) of cases where dermatologists were correct and AI was incorrect, dermatologists on average changed to the incorrect answer for 39% (4/10; 95% CI 23.2%-55.6%) of cases. When dermatologists were incorrect and AI was correct (25/94, 27%; 95% CI 24.0%-30.1%), dermatologists changed their answers to the correct answer for 46% (11/25; 95% CI 33.1%-58.4%) of cases. Additionally, the dermatologists’ average confidence in their decisions increased when the CNN confirmed their decision and decreased when the CNN disagreed, even when the dermatologists were correct. Reported values are based on the mean of all participants. Whenever absolute values are shown, the denominator and numerator are approximations as every dermatologist ended up rating a varying number of images due to a quality control step.

CONCLUSIONS

The findings of our study show that AI support can improve the overall accuracy of the dermatologists in the dichotomous image–based discrimination between melanoma and nevus. This supports the argument for AI-based tools to aid clinicians in skin lesion classification and provides a rationale for studies of such classifiers in real-life settings, wherein clinicians can integrate additional information such as patient age and medical history into their decisions.
Identification of Patient Perceptions That Can Affect the Uptake of Interventions Using Biometric Monitoring Devices: Systematic Review of Randomized Controlled Trials (Preprint)
Authors: Perlmutter Alexander , Benchoufi Mehdi , Ravaud Philippe , Tran Viet-Thi
Published: September 2020

BACKGROUND

Biometric monitoring devices (BMDs) are wearable or environmental trackers and devices with embedded sensors that
can remotely collect high-frequency objective data on patients’ physiological, biological, behavioral, and environmental
contexts (for example, fitness trackers with accelerometer). The real-world effectiveness of interventions using biometric monitoring devices depends on patients’ perceptions of these interventions.

OBJECTIVE

We aimed to systematically review whether and how recent randomized controlled trials (RCTs) evaluating interventions using BMDs assessed patients’ perceptions toward the intervention.

METHODS

We systematically searched PubMed (MEDLINE) from January 1, 2017, to December 31, 2018, for RCTs evaluating interventions using BMDs. Two independent investigators extracted the following information: (1) whether the RCT collected information on patient perceptions toward the intervention using BMDs and (2) if so, what precisely was collected, based on items from questionnaires used and/or themes and subthemes identified from qualitative assessments. The two investigators then synthesized their findings in a schema of patient perceptions of interventions using BMDs.

RESULTS

A total of 58 RCTs including 10,071 participants were included in the review (the median number of randomized participants was 60, IQR 37-133). BMDs used in interventions were accelerometers/pedometers (n=35, 60%), electrochemical biosensors (eg, continuous glucose monitoring; n=18, 31%), or ecological momentary assessment devices (eg, carbon monoxide monitors for smoking cessation; n=5, 9%). Overall, 26 (45%) trials collected information on patient perceptions toward the intervention using BMDs and allowed the identification of 76 unique aspects of patient perceptions that could affect the uptake of these interventions (eg, relevance of the information provided, alarm burden, privacy and data handling, impact on health outcomes, independence, interference with daily life). Patient perceptions were unevenly collected in trials. For example, only 5% (n=3) of trials assessed how patients felt about privacy and data handling aspects of the intervention using BMDs.

CONCLUSIONS

Our review showed that less than half of RCTs evaluating interventions using BMDs assessed patients’ perceptions toward interventions using BMDs. Trials that did assess perceptions often only assessed a fraction of them. This limits the extrapolation of the results of these RCTs to the real world. We thus provide a comprehensive schema of aspects of patient perceptions that may affect the uptake of interventions using BMDs and which should be considered in future trials.

CLINICALTRIAL

PROSPERO CRD42018115522; https://tinyurl.com/y5h8fjgx
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Authors: M J
Published: September 2020

BACKGROUND

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OBJECTIVE

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METHODS

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RESULTS

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CONCLUSIONS

telemonitoring
Nitric Oxide inhibits NF-κB-mediated survival signaling: possible role in overcoming TRAIL resistance (Preprint)
Authors: Bauer Joseph Alan , Lupica Joseph A. , DiDonato Joseph A. , Lindner Daniel J.
Published: September 2020

BACKGROUND

Chemoresistance is a major consequence of multicycle chemotherapy and can be attributed to constitutive activation of pro-survival signaling pathways. Nitric oxide is a ubiquitous signaling molecule which has been shown to inhibit several pathways involved with survival signaling in cancer cells. We have previously demonstrated the anti-tumor activity of a nitric oxide-donor, nitrosylcobalamin (NO-Cbl), mediated by increased expression of tumor necrosis factor-related apoptosis-inducing ligand (Apo2L/TRAIL) and its receptors in human tumors. We have also demonstrated that a functional Apo2L/TRAIL receptor is necessary for the induction of cell death by NO-Cbl and the Apo2L/TRAIL death receptor DR4 (TRAIL R1) is S-nitrosylated.

OBJECTIVE

The specific aim of this study was to examine the effects of nitric oxide (NO) on nuclear factor kappa B (NF-κB) and determine whether nitric oxide could sensitize drug-resistant melanomas to Apo2L/TRAIL via inhibition of NF-κB or Inhibitor kappa B kinase (IKK).

METHODS

Antiproliferative effects of NO-Cbl and Apo2L/TRAIL were assessed in malignant melanomas and non-tumorigenic melanocyte and fibroblast cell lines. Athymic nude mice bearing human melanoma A375 xenografts were treated with NO-Cbl and Apo2L/TRAIL. Apoptosis was measured by TUNEL. The activation status of NF-κB was established by assaying luciferase reporter activity, the phosphorylation status of IκBα, and in vitro IKK activity.

RESULTS

NO-Cbl sensitized Apo2L/TRAIL-resistant melanoma cell lines to growth inhibition by Apo2L/TRAIL but had minimal effect on normal cell lines. NO-Cbl and Apo2L/TRAIL exerted synergistic anti-tumor activity against A375 xenografts. NO-Cbl suppressed Apo2L/TRAIL- and TNF-α-mediated activation of a transfected NF-κB-driven luciferase reporter. NO-Cbl inhibited IKK activation, characterized by decreased phosphorylation of IκBα.

CONCLUSIONS

NO-Cbl treatment rendered Apo2L/TRAIL-resistant malignancies sensitive to the anti-tumor effects of Apo2L/TRAIL in vitro and in vivo. The use of nitric oxide to inhibit NF-κB and potentiate the effects of chemotherapeutic agents, such as Apo2L/TRAIL, represents a promising anti-cancer combination based on recent clinical investigations of anti-TRAIL antibodies for cancer treatment strategies.

CLINICALTRIAL

NA
The Future Alert of Inter-Arm Blood Pressure Difference in Young Healthy Population. (Preprint)
Authors: Essa Rawand , Ahmad Sr Sirwan Khalid , Hassan Sanaa Abdul-Sahib , Mohammed Rozhgar Qadir , Mire Zhalla Khdir
Published: September 2020

BACKGROUND

More than 100 years ago, the difference in blood pressure (BP) between arms was first reported. Recent studies have shown that different blood pressure between the right and left arm leads to cardiovascular events in the future.

OBJECTIVE

To establish the prevalence of an inter-arm blood pressure difference (IAD) and the dominant hands effect on the elevation blood pressure in young healthy population.

METHODS

This was a mixed research design, using a cross-sectional design; 3030 young, healthy participants, aged 15-40 years. BP was measured twice by both mercury sphygmomanometer and electronic simultaneously on both arms. has been carried out at Sulaimaniyah governorate/Kurdistan Region, Iraq, during the period 13th May 2019 to 22nd February 2020

RESULTS

Three thousand and thirty volunteers participated in our study {1377 (45.4%) male, 1653 (54.6%) female, mean age 19.56 ± 5.14 years old, mean BMI 22.37 ± 3.83} all were young and healthy. The sIABP was equal in 163 persons (5.37%), dIABP was equal in 222 (7.32%),The sIAD > 10 mmHg (26.13 %),and dIAD > or =10 mmHg was found in 927 (33.53%) in the right arm, and 32.4% in the left arm. 288 (9.50%) were current smokers, 290 (9.6%) were smoking hookah Most had IAD above 30% of their IAD was above 10 mmHg (P-value = 0.000). In 2692 volunteers, BP, initially recorded in the dominant hand (right arm), showed sIAD> or = 10 mmHg in 943 (37.12%) volunteers, and when first measurement was done in 338 left-handed volunteers it showed sIAD> or = 10 mmHg in 112 (34.14%), P < 0.001.

CONCLUSIONS

We conclude that significant inter-arm systolic and diastolic BP differences above (10 mm Hg) is common in the young, healthy population. Hand dominance is a significant consideration while measuring blood pressure. It is mandatory to measure blood pressure in both arms in a sitting position with a stable condition.
An Easy-to-Use Machine Learning Model to Predict the Prognosis of Patients With COVID-19: Retrospective Cohort Study (Preprint)
Authors: Kim Hyung-Jun , Han Deokjae , Kim Jeong-Han , Kim Daehyun , Ha Beomman , Seog Woong , Lee Yeon-Kyeng , Lim Dosang , Hong Sung Ok , Park Mi-Jin , Heo JoonNyung
Published: September 2020

BACKGROUND

Prioritizing patients in need of intensive care is necessary to reduce the mortality rate during the COVID-19 pandemic. Although several scoring methods have been introduced, many require laboratory or radiographic findings that are not always easily available.

OBJECTIVE

The purpose of this study was to develop a machine learning model that predicts the need for intensive care for patients with COVID-19 using easily obtainable characteristics—baseline demographics, comorbidities, and symptoms.

METHODS

A retrospective study was performed using a nationwide cohort in South Korea. Patients admitted to 100 hospitals from January 25, 2020, to June 3, 2020, were included. Patient information was collected retrospectively by the attending physicians in each hospital and uploaded to an online case report form. Variables that could be easily provided were extracted. The variables were age, sex, smoking history, body temperature, comorbidities, activities of daily living, and symptoms. The primary outcome was the need for intensive care, defined as admission to the intensive care unit, use of extracorporeal life support, mechanical ventilation, vasopressors, or death within 30 days of hospitalization. Patients admitted until March 20, 2020, were included in the derivation group to develop prediction models using an automated machine learning technique. The models were externally validated in patients admitted after March 21, 2020. The machine learning model with the best discrimination performance was selected and compared against the CURB-65 (confusion, urea, respiratory rate, blood pressure, and 65 years of age or older) score using the area under the receiver operating characteristic curve (AUC).

RESULTS

A total of 4787 patients were included in the analysis, of which 3294 were assigned to the derivation group and 1493 to the validation group. Among the 4787 patients, 460 (9.6%) patients needed intensive care. Of the 55 machine learning models developed, the XGBoost model revealed the highest discrimination performance. The AUC of the XGBoost model was 0.897 (95% CI 0.877-0.917) for the derivation group and 0.885 (95% CI 0.855-0.915) for the validation group. Both the AUCs were superior to those of CURB-65, which were 0.836 (95% CI 0.825-0.847) and 0.843 (95% CI 0.829-0.857), respectively.

CONCLUSIONS

We developed a machine learning model comprising simple patient-provided characteristics, which can efficiently predict the need for intensive care among patients with COVID-19.
Radical Scavenging Activity and Quercetin Content of Muntingia calabura L. Leaves Extracted by Various Ethanol Concentration
Authors: Pertiwi Ratih Dyah , Suwaldi  , Martien Ronny , Setyowati Erna Prawita
Published: September 2020

Muntingia calabura is broadly cultivated and has become a common roadside tree in Indonesia that is known as "Kersen," or cherry. The current study aimed to determine the activities of the phytochemical constituent (i.e., phenolic and flavonoid total contents) with various concentrations of ethanolic extract of M. calabura leaves (EEMC) to determine the best one and the in vitro antioxidant activities and quercetin content using TLC Densitometry. The extraction was carried out by maceration with various concentrations of ethanol (96% v/v; 70% v/v and 50% v/v) to obtain the ethanolic extract of Muntingia calabura, L leaves. The determination of Quercetin was conducted by Thin Layer Chromatography (TLC) densitometry, and the total phenolic was analyzed with reagent Folin-Ciocalteu while the flavonoid content we identified by applying the colorimetric method. The antioxidant capacity was measured using the radical scavenging assay of 1,2-diphenyl-2-picrylhydrazyl (DPPH). The phytochemical study showed that phenolics, saponins, tannins, and flavonoids were present in all EEMC. The extract obtained by 96% ethanol showed the highest total antioxidant activity, reducing power and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity. The same extract also exhibited the highest flavonoid content. However, the extract obtained by 70% ethanol showed the phenolic content, and the highest quercetin content was obtained by using 50% ethanol. The result from the EEMC analysis indicated that Muntingia calabura leaf extract contains essential bioactive compounds and shows potential as a source of antioxidants in M. calabura which uses 96% ethanol solvent and has the highest quercetin content in M calabura using 50% ethanol solvent.
The Profile of Anticancer Activities of Sambiloto Extract (Andrographis paniculata Nees) from Several Locations in East Java
Authors: Mutiah Roihatul , Luthfiana Fina , Suryadinata Arief , Anggraini Wirda , Listiyana Anik
Published: September 2020

Sambiloto (Andrographis paniculata Nees) contains andrographolid compound which has potentialas an anticancer. The difference of growth location has affected the distinction of metabolite content. Thisstudy aims to determine the profile of anticancer activities of A. paniculata extract from several locations inEast Java. The extracts from several locations were tested for activity on T47D cancer cell using MTT assaymethod. Thus, the result of this study describes that A. paniculata extract from several different locations doesnot provide significantly different anticancer activities with the amount of (p>0.05). The extracts which havemoderate anticancer activity were A. paniculata extracts from Selopuro Subdistrict Blitar Regency, SingosariSubdistrict Malang Regency, Lowokwaru Subdistrict Malang City, Klojen Subdistrict Malang City,Purwodadi Subdistrict Pasuruan Regency, Purwosari Subdistrict Pasuruan Regency, and PandaanSubdistrict Pasuruan Regency
Chemometrics Application for Grouping and Determinating Volatile Compound which related to Antioxidant Activity of Turmeric Essential Oil (Curcuma longa L)
Authors: Islamadina Rosy , Can Adelin , Rohman Abdul
Published: September 2020

Turmeric essential oil is known to have antioxidant activity. Various in vitro antioxidantactivity assays has been carried out. Related to this research, it tries to examine the antioxidantpotential of turmeric essential oil and see the composition that is responsible for antioxidant activitycombine with chemometrics. The research method used was a narrative review of 60 articlesobtained from several databases. The review conducted on profiling essential oil compounds thatidentified using GC-MS and evaluation of the antioxidant activity of turmeric essential oil with themost commonly used method including scavenging radical 2,2 diphenyl-1-picrylhydrazyl (DPPH)and 2,2-azinobis (3-ethylbenzothiazoline-6 sulfonic acid (ABTS). Analysis methods used forgrouping various multivariate data subjects and determaining the relationship between thevariables were Principal Component Analysis (PCA) and Cluster Analysis (CA). According to thereview, turmeric essential oils are proven to have potential antioxidant activity and have variationsin chemical contents. PCA was success for grouping subjects with various correlated variables,determining variables wich the most influential and correlation between variables. CA method canbe used to group samples without requiring mutually correlated variables.
The Effect of Metanolic Extract and Ethyl Acetate Fraction of Kepel Fruits to Lipid Peroxide Concentration in Liver of CCl4-induced Rat
Authors: Arifah Mitsalina Fildzah , Martono Sudibyo , Riyanto Sugeng , Airin Claude Mona
Published: September 2020

Accumulation lipid peroxidation can lead to the formation of malondialdehyde to generatefree radicals. Antioxidant will minimize free radical related health problems, such as naturalantioxidant from meat of kepel (Stelechocarpus burahol) (Blume) Hook. F. & Thompson) fruits.Antioxidant activities of methanol extracts and acetate ethyl fractions meat of kepel fruits calculatedprofile of malondialdehyde concentration (ng/mL) in CCl4 induced acute liver toxicity in femaleSprague Dawley rats using ELISA competitively method. All of groups induced CCl4 i.p. at 0 h, exceptuntreated and solvent control group, then vitamin C , methanol extracts and acetate ethyl fractionsp.o. once daily for 72 h. Identification of secondary metabolite was using phytochemical screeningand Thin Layer Chromatography (TLC). Liver weighed and calculated relative organ weight (ROW)of liver, then all of data analyzed using statistic tests, One Way ANOVA and Kruskall Wallis. Thisstudy showed methanol extracts can decrease MDA concentration, ALT and AST were more potent(significantly p<0.05) than acetate ethyl fractions and vitamin C. The TLC analysis identified methanolextracts have same polarity with quercetin (Rf = 0,26) and acetate ethyl fractions showed otherflavonoid class, except rutin and quercetin. ROW of acute liver toxicity in rats increased significantlyin CCl4 and vitamin C groups.
Comparison of Anti-oxidant Activity of Five Elected Wild Commercial Mushrooms in Four Different Solvents as an Alternative Oxidative Stress Reliever
Authors: Salamat Shahnaz , Shahid Muhammad
Published: September 2020

Mushroom also known as a lit source of nutritional and therapeutical component so in order toevaluate the usefulness of the Pakistani wild mushroom strains as the possible nutracueticals, adetailedstudy entailing several tests for the determination of anti-oxidant potential was carried out on the electedmushrooms in four different solvents. Strains of Lentinus edodes, Pleurotus ostreatus, Volvariella volvacea,Pleurotus eryngii and Ganoderma lucidum were extracted for this particular purpose in the water, n- butanol,n-hexane and choloroform solvents. Test models including Total Phenolic Content assay, Total FlavonoidContent assay, 2,2-diphenyl-1,1-picrylhydrazyl (DPPH) Scavenging Activity assay and Reducing Powerassay were utilized for carrying out the comparative analysis among the selected mushrooms. The acquiredresults indicated that the extract of Volvariella volvacea and Pleurotus eryngii possess copacetic anti-oxidantpotential and can be utilized as oxidative stress reliever in humans. Furthermore, extraction studies alsoindicated that water is the most suitable solvent for anti-oxidants extraction for these mushrooms. Finding ofthe anti-oxidant potential for elected wild mushrooms contra indicate that these mushrooms can be safelyexploited as a amended natural anti-oxidant in comparison to its synthetic counterpart.
The Role of Subjects in Kuntowijoyo's Transformative Thought and It's Relevance to the Prophetical Social Transformation
Authors: Khasri M. Rodinal Khair , Mustansyir Rizal
Published: September 2020

Paper ini membahas tentang analisis filsafati atas peran subjek di dalam pemikiran transformatif Kuntowijoyo, sebagai langkah paradigmatik untuk mewujudkan transformasi sosial profetik. Penelitian ini menggunakan model pendekatan historis-faktual mengenai tokoh. Adapun data pustaka primer dan sekunder dianalisis dengan langkah interpretasi dengan menggunakan pendekatan hermeneutika Gadamer, kemudian menemukan kesinambungan historisnya, yang selanjutnya direfleksikan sebagai suatu rangkaian pemahaman atas sejarah yang diakronis.Adapun hasil penelitian ini yaitu terdapat peran subjek yang sangat signifikan di dalam proses pembentukan kesadaran sejarah yang menjadi prasyarat transformasi sosial profetik. Bertitik-tolak pada tiga komponen penting dalam hermeneutika dialektis Gadamer, maka subjek di dalam membangun epistemologi profetik yang menggerakkannya di dalam transformasi sosial selalu terikat dengan kebudayaannya. Di samping itu ia juga menyejarah, dan melakukan peleburan horizon (fusi horizon), yaitu horizonnya pada setiap babak sejarah dan horizon subjek yang lain. Oleh sebab itu, dengan bertitiktolak dari epistemologi profetik—yang mendialektikakan wahyu (Al-Qur’an dan Hadis) dengan akal manusia—transformasi sosial profetik dapat dicapai.
Perspektif Jaringan Pertukaran Maritim terhadap Sumber-sumber Pangan di Pulau-pulau Kecil Kabupaten Wakatobi Sulawesi Tenggara
Authors: Rabani La Ode , Bani Adhi Rahman
Published: September 2020

This article analyzes the sources of foods in small islands from the maritime exchange network perspective. The location of the research was a group of small islands in Southeast Sulawesi. This research found that resources of food in the small islands came from the other region as part of the process of exchanges maritime networks, especially from the Wallacean line connection and other main islands of Indonesia. Process and its form become local culinary, were other a part of the creative process, and the expression of its citizens. Some supporting tools for processing resources of food also identified as an invention from the local society have been fully health standards. To support that argument, the authors identifying the origins of food resources, processing, and preserving strategies. Knowledge about the food resources on the small islands contributes to the understanding of the globalization connections in small Islands, a wider world at the local level.
JAMALOKE: Bingkai Kecintaan pada Tanah Air dan Kesia-siaan
Authors: Husain Sarkawi B.
Published: September 2020

Novel Jamaloke, adalah sebuah novel yang ditulis oleh anak dari pelaku sejarah Revolusi Indonesia di Surabaya. Novel ini didasarkan pada buku harian ayahnya. Isi novel tidak seluruhnya tentang realitas sesungguhnya dari peristiwa saat revolusi yang terjadi di Surabaya. Dalam konteks ini, pembaca dihadapkan pada persoalan hubungan antara historiografi dan karya sastra (dalam bentuk novel). Historiografi dan karya sastra keduanya merupakan simbol verbal, tapi memiliki perbedaan yang tegas antara keduanya.
Developing teachers’ creative writing skills to support the school literacy program
Authors: Iswatiningsih Daroe , Pangesti Fida , Sudiran S.
Published: September 2020

The problem faced by SDN Girimoyo 02 in implementing the school literacy movement was the lack of the number and type of reading material. This problem was overcome through the empowerment of teaching writing skills. Therefore, the aim of this community service was to provide creative writing assistance for SDN Girimoyo 2 teachers so that teachers can contribute reading material to fill the existing gaps. The service method was carried out through workshops and collective and personal mentoring, face-to-face and online. The results of the activity show that the teacher's main problem was exploring ideas or topics to be written about and starting to write. There were doubts and distrust of the teacher when writing, afraid that the idea is not good, not quite right, and not good. Likewise, when starting to write, the first sentence of the writing is felt to be insufficient. For this reason, the handling was carried out on the teacher by strengthening self-confidence, practicing simple writing that starts from experience to develop in writing accompanied by arguments or rationality, and writing assistance. Through this activity, teachers feel very helpful and motivated to optimize the implementation of GLS in schools. Teachers have been able to access various information related to cultural literacy and produce a joint workbook.
Introduction and early measurement of carbon footprint concepts to respond the challenge of SDGs-Goal 13
Authors: Santhyami S. , Al Mubarok Moh. Isna , Nurzahra Vakha Yulia
Published: September 2020

One of the efforts to prevent the effects of climate change was the introduction of the concept of carbon footprints from an early age to students. Science subjects in this school have included elements of environmental knowledge in their subject matter. However, mitigation and adaptation efforts to climate change were still lacking recognition. The purpose of this study was to introduce and measure the extent to which elementary students are able to recognize the concept of carbon footprints and can use a simple carbon footprint calculator application in climate change mitigation and adaptation efforts. The study was conducted at MIM Kupang Karangdowo Klaten, Central Java. The activity was carried out on February 19, 2020 with the method of lectures, interviews, and simulations, followed by 11 teachers and 21 grade VI students. The flow of activities was divided into 3, namely: (1) counseling/explanation of the carbon cycle, global warming, carbon footprint and carbon footprint calculator, (2) interviews about the student's daily and weekly lifestyle or carbon footprint pattern, (3) socialization of the footprint calculator application carbon and usability observations. The activity ended with a simulation of a carbon footprint calculator for several students. From the study conducted, it can be seen that students are interested in this carbon footprint concept and were technically assessed as being able to use a carbon calculator without significant obstacles.
Psychological change on inclusive educators through emotional regulation
Authors: Winarsunu Tulus , Saraswati Putri
Published: September 2020

Inclusive education requires special educators who have good abilities in regulating their emotion. This is because these educators not only educate normal and average intellectual abilities of students, but varies. Differences in the characteristics of students in inclusive classes not only lie on their intellectual abilities, but also it is very possible for these students to have a special condition on communication, social skills, autonomy (living skills), and emotional control. Therefore, in teaching and learning activities, educators’ focus is not solely on academics, but special educators have to share their attention on the non academic behavior of students. Not surprisingly, the feelings or emotions felt by these special educators become varied and tend to be negative, such as annoyance, pity, confusion, sadness and etc. The method implemented was psychoeducation which focus is on lecturing and discussing. Psychoeducation exists to help educators regulate the emotions they feel. The psychoeducation that was carried out gave 52.9% of special educators an increase in emotional regulation, 17.6% decreased, and the rest had no change.
Awareness and response to Coronavirus Disease (Covid-19) epidemic among the Arab population in the Eastern Mediterranean Region and Arab Peninsula
Authors: Saleh Mhammad , Saleh Marwan , Zahid Mohammed Nabil
Published: September 2020

Objectives: This online survey planned to analyze the knowledge and apprehension about coronavirus among the Arab populations. 

Methods: a cross-sectional questionnaire-based survey was conducted from 15th May 2020 to 27th May 2020. The survey included a total of 443 Arab participants. Divided into four groups according to the age; under 20 years old (28 participants), 20- 40 (359), 40- 60 (49), and 7 participants were over 60. According to gender; male (318 participants) and female (125). Based on education level, participants were categorized as a secondary school (5 participants), high school (28), university graduated (327), and postgraduate (83). 

Results: Most of the participants showed a good adaptation for the precautions concerning isolation and quarantine. 299 participants stayed at home during the COVID-19 outbreak by taking a break from jobs or performing their jobs from home. 144 participants performed partial or full-time jobs from 20-60 groups of age. Most of the population were dependent on social media to receive the update about the virus. 141 participants said that they are not up to date enough about the COVID-19 related to the language barrier.

Conclusion: The majority of the participants had heard about COVID-19 and were aware of the infection control measures. Most of the participants strictly adapted to quarantine during the outbreak. Further steps need to be taken to enhance the social media accounts and internet websites in the Arabic language which concern medical and educational content.
Infection Prevention and Control Measures for COVID-19 among Medical Staff in Nineveh Governorate, Iraq
Authors: Kassim Zakaria A , Al-Mulaabed Sharef , Younis Saif W , Abutiheen Ali A
Published: September 2020

Objectives: To assess the adherence to IPC measures among medical staff working in Nineveh governorate during COVID-19 pandemic.

Methods: A cross sectional study, using an online survey sent to different medical staff in Nineveh. The questionnaire was composed of two parts, the first included demographic information, and the second covered IPC measures. Survey was completed by medical staff witnessed COVID-19 pandemic in Nineveh governorate.

Results: The total sample was 412, of whom, 316 (77%) were males and 142 (35%) were physicians. Overall, the percentage of staff following different IPC measures was ranging from 31 % in wearing head cover, to 97% in keeping clean hands constantly. Main missed points were found in respiratory hygiene, physical distancing and self-isolation. Females were more likely to apply bandages to wounds and wearing gloves before examining patients. Compared to other medical staff, physicians were less compliant to washing hands, putting waste in designated places and wearing protective cloths. Those who work in hospitals were better compliant with sterilizing hands before entering home.

Conclusion: The adherence to IPC measures was ranging from less than one-half in wearing sterile head cover, to nearly all respondents in keeping clean hands. There is a great need to provide support as well as training in regards to IPC in Nineveh governorate city.
A Problem-based Learning Approach and Its Effects on the Writing Performance of Nigerian Undergraduates
Authors: Aliyu Muhammad Mukhtar , Fung Yong Mei , Rashid Sabariah Md. , Nimehchisalem Vahid
Published: September 2020

Writing is considered as an important but a difficult language skill for undergraduates. To develop writing skills, undergraduates need to be given the opportunity to interact with and help one another in the writing process. They also need to be supported by teachers in the process. However, most of the traditional teaching methods adopted by writing instructors in Nigeria do not allow students to interact in the learning process. In this light, this study investigates the effects of a problem-based learning approach (PBL) on the writing performance of Nigerian undergraduates. The study employed a pre- and- post-treatment quasi-experimental research design. The participants (n=18) involved in the study were an intact class of second-year students taking English composition course and two tutors in a college in North-eastern Nigeria. The study was conducted over a period of 12 weeks. To determine the effects of PBL on the participants’ writing performance, a rating scale was used to rate the content, organisation, vocabulary, grammar and mechanical accuracy of the pre- and post-treatment writing scripts. A paired-sample t-test analysis was run to compare the mean scores of the undergraduates’ pre- and post-treatment writing. The results showed significant improvements in all the components (content, organisation, vocabulary, language use and mechanics) of the participants’ writing in the post-treatment. The paper concludes with a discussion on the pedagogical and theoretical contributions of the findings. It provides writing instructors with a student-centred approach that would help to develop their students’ writing skills.
EMI in Vietnam: What High School Teachers Think and Do
Authors: Nguyen Thi Phuong Doan , Nguyen Van Loi
Published: September 2020

The current case study was driven by a recent policy on using English as a medium of instruction (EMI) in the mainstream school system in Vietnam. It aimed to explore what science teachers believed and reported doing about EMI in teaching science subjects in the high school context. Nine EMI teachers of different science subjects at a specialized high school in the Mekong Delta of Vietnam participated in a semi-structured interview. Thematic analysis revealed the perceived positive impacts on teachers’ and students’ English proficiency, and negative influences on science content coverage. In practice, the teachers reported a focus on simple contents, explaining specialized terminologies and key concepts as the input. They mainly employed a lecture style and teacher initiation-student response interaction, switching between English and Vietnamese during their lessons. These results imply that EMI across the curriculum has the potential to improve English proficiency of students, but the EMI policy needs to consider its transparency in goals and communication to stakeholders especially teachers and school managers.