bluuebunny/crossref_metadata_2025 huggingface dataset:
Straightforward synthesis and mechanism insight of TiO2/α′-AgVO3 heterostructure with enhanced photocatalytic activity
Authors: Liu Yangbin , Liu Nian , Lin Minghua , Zhou Yun , Ouyang Xiaoping
Published: November 2022

With the deterioration of our environment, it is imperative to develop high-performance photocatalysts for ‘green’ environmental protection. In this work, a novel TiO2/α′-AgVO3 heterostructure has been successfully synthesized by a straightforward hydrothermal method for the photodegradation of Rhodamine B (RhB). Specifically, TiO2/α′-AgVO3 with a molar ratio of 4:1 displays excellent stability and outstanding photodegradation efficiency, which can remove 94% RhB within 120 min visible light irradiation. The free radical capture experiments demonstrate that h+ and ·OH act as pivotal parts in the photodegradation of RhB. Additionally, the enhanced photocatalytic performance of TiO2/α′-AgVO3 heterostructure is mainly attributed to the appropriate surface areas, broadened range of light adsorption, more photocarrier generation, and effective charge separation. This research reveals that TiO2/α′-AgVO3 heterostructure is an efficient visible light photocatalyst and is expected to be applied in organic sewage degradation.
Study of vortex dynamics in an a-MoGe thin film using low-frequency two-coil mutual inductance measurements
Authors: Mandal Soumyajit , Basistha Somak , Jesudasan John , Bagwe Vivas , Raychaudhuri Pratap
Published: November 2022

We extract the vortex lattice (VL) parameters using low-frequency two-coil mutual inductance measurements in a 20-nm-thick superconducting amorphous Molybdenum-Germanium (a-MoGe) thin film. We fit the temperature dependence of ac penetration depth in the mixed state using a model developed by Coffey and Clem and demonstrate a procedure for extracting VL parameters such as the restoring pinning force constant (Labusch parameter) VL drag coefficient, and pinning potential barrier. We show that the extracted parameters follow the magnetic field variation expected for a weakly pinned two-dimensional vortex lattice.
Single and double electron excitation transition rates and oscillator strengths calculations in the study of the x-ray absorption spectrum of Neon
Authors: Suleiman Jamal
Published: November 2022

We report a new study of the x-ray absorption spectrum of Neon near the K-edge and near the KL-edge. The study is performed by calculating the transition probabilities and oscillator strengths for excitations from the ground state to singly and doubly excited states, the calculations were performed using multi-configurational Dirac-Fock (MCDF) method. Breit interaction between electrons and finite nuclear size effects were taken into account during the calculations, the transition probabilities were convoluted into Lorentzian line shape profiles. The results of the calculations were then compared to previous measurements of the x-ray absorption spectrum of Neon, good agreement was observed and many features in the spectrum were explained.
High-power diode lasers with in-situ-structured lateral current blocking for improved threshold, efficiency and brightness
Authors: Elattar M , Brox O , Della Casa P , Mogilatenko A , Maaßdorf A , Martin D , Wenzel H , Knigge A , Weyers M , Crump P
Published: November 2022

We present high-power GaAs-based broad-area diode lasers with a novel variant of the enhanced self-aligned lateral structure ‘eSAS’, having a strongly reduced lasing threshold and improved peak conversion efficiency and beam quality in comparison to their standard gain-guided counterparts. To realize this new variant (eSAS-V2), a two-step epitaxial growth process involving in situ etching is used to integrate current-blocking layers, optimized for tunnel current suppression, within the p-Al0.8GaAs cladding layer of an extreme-triple-asymmetric epitaxial structure with a thin p-side waveguide. The blocking layers are thus in close proximity to the active zone, resulting in strong suppression of current spreading and lateral carrier accumulation. eSAS-V2 devices with 4 mm resonator length and varying stripe widths are characterized and compared to previous eSAS variant (eSAS-V1) as well as gain-guided reference devices, all having the same dimensions and epitaxial structure. Measurement results show that the new eSAS-V2 variant eliminates an estimated 89% of lateral current spreading, resulting in a strong threshold current reduction of 29% at 90 μm stripe width, while slope and series resistance are broadly unchanged. The novel eSAS-V2 devices also maintain high conversion efficiency up to high continuous-wave optical power, with an exemplary 90 μm device having 51.5% at 20 W. Near-field width is significantly narrowed in both eSAS variants, but eSAS-V2 exhibits a wider far-field angle, consistent with the presence of index guiding. Nonetheless, eSAS-V2 achieves higher beam quality and lateral brightness than gain-guided reference devices, but the index guiding in this realization prevents it from surpassing eSAS-V1. Overall, the different performance benefits of the eSAS approach are clearly demonstrated.
Influence and Correction of Wavefront Primary Aberrations for Radio Telescopes using Aberration Theory
Authors: Xiang Bin-bin , Wang Wei , Ban You , Lin Shang-min , Wen Zhi-gang , He Da-lin , Cai Ming-hui
Published: November 2022

Dual-reflector antennas are widely used in astronomical observations and satellite communication. Structural deformations of the reflectors for radio telescopes are inevitable in outside working conditions due to exterior environment loads, which will cause distortion in the surface of the primary reflector and displacement of the subreflector, then lead to gain degradation and misalignment. In this paper, the influence and correction of misalignment in a dual-reflector antenna have been studied. From the perspective of wavefront aberration, a method is proposed to correct the wavefront primary aberration by adjusting the subreflector position. The characteristics of wavefront errors caused by structural deformation of the reflector have been analyzed, and relationships between the position motions of the subreflector and the Seidel wavefront aberrations are derived. The adjustment quantities of the subreflector are also derived. The results show the appropriate positional change of the subreflector in the lateral and axial directions can effectively correct the effects of the tilt and defocus in the primary aberrations caused by antenna structural deformations.
Improved absolute frequency measurement of the strontium ion clock using a GPS link to the SI second
Authors: Jian Bin , Bernard John , Gertsvolf Marina , Dubé Pierre
Published: November 2022

We report on an improved absolute frequency measurement of the

5

s

2

S

1

/

2

–

4

d

2

D

5

/

2

optical transition of a single trapped strontium ion using a Global Positioning System (GPS) link to the SI second. Compared to our previous measurement, the systematic uncertainty of the optical clock has been reduced from

1.5
×

10

−
17

to

1.2
×

10

−
17

. The measurement campaign was performed over a two-week period in June 2017, with a total measurement time of 92 h. The traceability to the SI second through International Atomic Time was achieved through a GPS link using the Precise Point Positioning method. The dead time uncertainty of the link between the optical clock and the maser was evaluated using standard methods based on a model of the maser noise and on the optical frequency measurement uptimes. The measured frequency of the 88Sr+ ion

5

s

2

S

1

/

2

–

4

d

2

D

5

/

2

transition is

444
779
044
095
485.49
(
19
)

Hz. This result is in excellent agreement with our previous measurements and the uncertainty has been reduced by almost a factor of four, from a fractional frequency uncertainty of

1.7
×

10

−
15

to

4.3
×

10

−
16

.
Bottom drag measurements in experimental wind tunnel tests
Authors: Krzysiak A
Published: November 2022

The paper presents the results of wind tunnel tests aimed at determining the model bottom drag in the case of rocket model tests. The balance measurement technique of the rocket model fixed in the wind tunnel test section by the rear sting was discussed. The model was equipped with the two parallel boosters. Based on the wind tunnel test of the rocket twin model the values of the bottom pressure was determined for tested Mach numbers. An algorithm of wind tunnel corrections was shown, which allowed the total drag determination in a case of the rocket active or passive rocket flight. The test results showed the necessity of the bottom drag measurements in wind tunnel tests.
Numerical analysis of influence of various bluff-body shapes on diffusion flame dynamics
Authors: Kantoch Robert , Wawrzak Agnieszka , Tyliszczak Artur
Published: November 2022

In this paper, various bluff-body shapes (cylindrical, square, star) and two different surface topologies (smooth, wavy) are applied as passive tools for controlling a non-premixed hydrogen flame in a combustion chamber. We focus on the dynamics of the flame and its time-averaged characteristics in the close vicinity of an injection system within formed recirculation zones and also in a far-field. The research is performed with the help of large-eddy simulations (LES) method using the ANSYS Fluent software and a high-order academic code SAILOR. Flame behaviour is found to be strongly dependent on the geometry of the bluff-body whereas its wall topology affects the flame characteristics only slightly. In the cases with the square and star bluff-body, small vortical structures originating at the corners deform large vortical structures created by the Kelvin-Helmholtz instability mechanism. This intensifies the mixing and combustion process and, in the configuration with the square shape bluff-body, translates to the shortening of the recirculation zone by 15% of the equivalent bluff-body diameter and the flame, which in the axis develops closer to the bluff-body. The star shape leads to the most uniform flame at the radial border or the recirculation zone.
Strouhal number and vortices in far wake of cylinder
Authors: Duda D , Yanovych V , Horáček V , Uruba V
Published: November 2022

The wake past a smooth cylinder perpendicular to the flow is studied 15D (cylinder diameters) downstream by using particle image velocimetry (PIV). Spatial shedding period is used to estimate the spatial Strouhal number (Sh) and to compare with time-resolved hot-wire anemometer (HWA). The vortices are detected within the spatial fluctuation field. The statistical vortex properties do not change within the explored range of Reynolds numbers (from 5 000 to 60 000), similarly the spectra and Sh.
The Effect of Layer Thickness on Impact Strength Characteristics of ABS and PLA Materials
Authors: Kholil A , Syaefuddin E A , Supardi F , Wulandari D A
Published: November 2022

This study aims to determine the impact strength of the Fused Deposition Material (FDM) additive manufacturing with the parameters in different layer thicknesses between 0.10 – 0.30 mm. The specimen manufacturing process refers to ASTM D256 Standards with ABS (acrylonitrile butadiene styrene) and PLA (polylactic acid) materials. Based on the test results, ABS specimens with a layer thickness of 0.10 mm had the largest impact strength with 0.078 J/mm2, while the smallest impact strength was found in PLA specimens with a layer thickness of 0.20 mm and 0.30 mm with an impact strength of 0.047 J/mm2. The value of impact strength on ABS and PLA materials varies with each layer thickness change.
Electrodeposition of CU2O Films at Room Temperature for Methylene Blue Photodegradation
Authors: Budi S , Syafei D I , Yusmaniar  , Khasanah Q F , Laxmianti D
Published: November 2022

The Cu2O films were synthesized using the electrodeposition technique at room temperature. To investigate the phase, electrochemical properties, and photocatalytic activity of the Cu2O films, the duration of electrodeposition was varied. The catalytic activity of methylene blue (MB) photodegradation was studied. The X-ray diffraction measurement showed that single-phase Cu2O was successfully formed from the prepared films. Electrochemical properties analysis under visible light irradiation showed that a high photocurrent recorded by the linear sweep voltammetry technique was obtained from Cu2O synthesized with deposition time of 60 minutes. This result could be associated with the lowest resistance charge transfer of the sample compared to other deposition times measured using the electrochemical impedance spectroscopy method. The catalytic activity showed that this Cu2O is the most effective photocatalyst, as it provides a 51.5% degradation of MB dye.
Microwave Absorption Properties of Ba0,9 Ca0,1 Fe12O19/Fe2O3 Nanocomposite Prepared using Planetary Ball Milling
Authors: Handoko E , Marpaung M A , Sugihartono I , Fahdiran R , Saputra A , Imaniar F , Aulia T B , Taufiq A , Irianti Y , Umaisaroh U , Alaydrus M
Published: November 2022

In this paper, the nanocomposite magnetic material (NCMM) of substituted BaFe12O19 and Fe2O3 was synthesized by using solid state reaction (SSR) method. Ba0.9Ca0.1Fe12O19 with different absorption frequencies were chosen to fabricate the nanocomposite with Fe2O3. The crystalline structure and microwave properties were investigated with X-ray diffraction (XRD) and a vector network analyzer (VNA) in the frequency range of 7-13 GHz, respectively. The results show that crystallographic analysis resulted the phases as BaFe12O19 and Fe2O3. The NCMM is an optimum microwave attenuation material with a broad frequency range. Its minimum reflection loss (RL) is about –38.42 dB. The results indicated that MCMM have a good RL and broadband absorption in the microwave frequency range.
Optimization of the Mechanical Properties of Coconut Shell Briquettes with a Tapioca Flour Adhesive
Authors: Nasbey H , Yahya L A , Budi AS
Published: November 2022

The manufacture and characterization of coconut shell briquettes using tapioca as adhesive were conducted. The sample is created using different tapioca flour concentrations: 1%, 3%, 5%, 7%, and 9%. All coconut briquette samples were dried for 30, 60, and 90 minutes. Coconut briquette samples were characterized using scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), Fourier transforms infrared spectroscopy (FTIR), compression tests, and burn rate tests to analyze the effect of variations in tapioca flour concentration on the mechanical properties and burn rate of coconut briquettes. It can be confirmed from SEM-EDX results that the content of coconut shell briquettes is dominated by carbon (C), oxygen (O), and potassium (K) elements. FTIR results show absorption of O-H and C=C groups. The tapioca flour concentration affects coconut shell briquettes’ mechanical properties and burning rate based on the compression test and burning rate. The highest compressive strength value belonged to coconut shell briquettes with a concentration of 9% tapioca flour with a drying time of 30 minutes or 1.63 MPa.
Circuit Simulation of the DC-DC Converter with Variation of PWM Load in Solar Panel Electrical Energy Storage
Authors: Indrasari W , Rama G , Setiadi R N
Published: November 2022

In storing solar energy as an alternative energy source, we need a control system called a DC-DC converter. This system can optimize the transmission of energy from solar panels to be stored in the battery. This research aims to develop a high-efficiency control system for transmitting electrical power from solar panels to batteries. The circuit simulation of a DC-DC converter, with a buck topology, was carried out using the LT Spice software to determine the noise value at the system output voltage. The DC-DC buck converter circuit simulation is carried out by optimizing nine load resistor values (R) variations. The resistor variations used are 10 Ω, 50 Ω, 100 Ω, 150 Ω, 200 Ω, 250 Ω, 300 Ω, 350 Ω, and 400 Ω. The input voltage is set at 20 Volts. Meanwhile, the duty cycle is selected at 60%. The simulation results show that the smallest noise is 2.83 mV, derived from a circuit with a load of 400 at the filter design of L is 33.8 mH and C is 750 nF. The system output voltage obtained is 12.17 V.
Heart Sound Signal Analysis for Digital Auscultation
Authors: Busono P , Karim S , Kamaruddin A , Yogiswara I P A
Published: November 2022

Cardiac auscultation is the examination of the heart by listening to the sound produced by the heart through a stethoscope. Heart sounds can provide information about the functioning of the heart valve condition as well as information about the structural abnormalities of the heart. However, it needs intensive training for mastering. The objective of the work was to develop an algorithm for heart sound signal classification applied to computer-assisted digital auscultation in order to identify pathological events. The method can be described as follow: data collection, pre-processing, segmentation, feature extraction, and classification. The data were collected from volunteers using an electronic stethoscope and from a database available in the internet. The heart sound data were then extracted and split into training, validation, and testing datasets. In the training process the dataset was labeled as normal and abnormal (aortic stenosis, mitral stenosis, aortic regurgitation, pulmonic regurgitation, tricuspid stenosis, flow murmur, and patent ductus arteriosus). The convolution neural network is used as a classifier in the learning process to obtain the learning model. The model was validated and tested using the available datasets. The experimental results show that the algorithm has the capability to classify the heart sound into normal and abnormal with a high detection rate.
A preliminary report on seismicity declustering methods and completeness magnitude in eastern Sunda Arc
Authors: Risanti H , Realita A , Fahmi M Nurul , Prastowo T , Madlazim
Published: November 2022

Data declustering separates mainshocks from both foreshocks and aftershocks while a reliable estimate of completeness magnitude is a key point in seismic parameter determination. These play a role in seismicity-related work. In this preliminary study, we reported seismicity in two Indonesian provinces, namely NTB and NTT, as part of eastern Sunda Arc using the USGS catalogue during 1970-2021 based on performance of three declustering methods (Gardner and Knopoff, Reasenberg, Uhrhammer). These methods were tested along with three techniques of M
c determination (MAXC, EMR, BC) provided by ZMAP to estimate minimum magnitude cut-offs, leading to an accurate completeness magnitude. After careful examination, the Reasenberg and BC techniques were proved to be suitable for characterising seismicity in the regions of interest, where M
c was calculated under a linear assumption of the cumulative frequency-magnitude distribution (FMD), widely known as the Gutenberg-Richter law. The results revealed that b and a parameters are influenced by the choice of a specific declustering algorithm and calculation of M
c. NTT was found to have a higher level of seismicity than NTB and seismicity rates in the southern part of both provinces were higher than those in the northern part. However, the number of strong ground motion with M
w ≥ 6.5 in the northern area was larger than that in the southern, indicating the potency of Flores Back-arc Thrust for generating large earthquakes hence possible tsunamis.
Analysis of Flare Occurring Based on Sunspot Changing Patterns Using Zurich Method in February – April 2022 at the Astronomy Laboratory of Physics FMIPA State University of Malang
Authors: Yogihati C I , Shofi I A , Heriyanto H
Published: November 2022

The star closest to our Earth is the sun with an average distance of 149,680,000 km. The sun is plasma with a very high temperature. The most easily observed solar activity from Earth are sunspots and flares, where flares on the sun can affect the Earth’s atmosphere. Therefore with this, research was carried out in February - April 2022 at the Laboratory of Astronomy Physics, State University of Malang with a geographical location of 07° 57’ 39” South Latitude, 112° 37’ 9.2” East Longitude, and 7.9607° North Latitude at an altitude of 465 meters with using the Celestron telescope. This study aims to determine the pattern of changes in sunspots until the occurrence of flare, and to find out how to determine the occurrence of flare. This study used a descriptive approach based on the daily data that had been observed. In classifying sunspots, the Zurich method is used. The development of sunspots obtained in daily data shows changes in sunspot development patterns and data on the influence of flares that occur on the surface of the Earth such as satellite damage and auroras reported by NASA show that flare occur on the surface of the sun. Based on the analysis of sunspot classification, it shows that flares occur in classes C, D, E, and F. The occurrence of these flares can be seen in the news released by NOAA. It can be concluded that flares do not always occur in large class sunspot classifications. However, the small class was able to produce a flare.
Comparative Study between Fabricated Plastic Scintillator and Existing Product for Gamma Detection
Authors: Pancoko M , Nuri H L , Manaf A , Dimyati A , Jami A , Subhiyah H
Published: November 2022

A plastic scintillator with an injection method has been developed for a gamma radiation detector. The scintillator was made from the main matrix of polystyrene (PS) pellets with the addition of primary dopant PTP (para-terphenyl) 1.5% wt and secondary dopant as wavelength shifter (WLS) POPOP (1,4-bis [2- (phenyloxazolyl) )] - benzene) 0.01 - 0.05% wt. The mixture of pellets and dopants was fed to the extruder machine to obtain scintillating pellets and then referred to the machine to obtain a 3 mm thin plate plastic scintillator. The evaluation of absorption using a spectrophotometer UV-Vis showed that PS absorbs photons at a wavelength of 310 – 340 nm and PS containing POPOP produces a maximum emission at a wavelength of 421 nm. The evaluation of cesium 137 (137Cs) and cobalt 60 (60Co) gamma spectrum using the photomultiplier tube (PMT) Hamamatsu R878 showed the results of Compton spectrum characters with a gross counting maximum of 0.78 and 0.89, respectively, compared to the commercial plastic scintillator. The results of this study are expected to be usefully utilized in the development of a large-volume plastic scintillator for the radiation portal monitor (RPM).
Vertical Structure of PM2.5 and CO2 Concentrations in The Greater Bandung Air Basin
Authors: Mustofa A H , Chandra I , Salam R A , Rachmawati L M
Published: November 2022

The Greater Bandung air basin, surrounded by mountains and hills, has a unique topography that could block the horizontal displacement of pollutants. Consequently, air pollution in these areas is affected by the vertical-spread pattern of pollutants. Previous studies identified that PM2.5 and CO2 concentrations in Telkom University Bandung have a similar trend data vertically up to 30 m above the ground. Therefore, this study was conducted to observe and analyze the distribution of pollutants in the vertical direction and broaden the measurement points using drones. A drone was chosen considering the available high building is limited, also to minimalize the spatial differences. The measuring parameters are PM2.5 and CO2 concentrations and meteorological conditions (temperature/T, relative humidity/RH, and pressure/P). Two different times are chosen that are at day time (August 31, 2019) and nighttime (September 30, 2019), at altitudes up to ~80m. During measurements, it was indicated that the change of the rotor or the drone’s propeller speed affected the airflow. Results show that there are indications of PM2.5 deposition in the morning, which decreases to ~20 μg/m3 after the height of >40 m. The PM2.5 concentrations have been lifting and mixing evenly from the afternoon to the evening, increasing at night to ~15 μg/m3. As for CO2, concentrations level up to ~80 m altitude do not have a significant or relatively stable change.
Development of Diagnostic Test of Learning Difficulties for High School on Newton’s Law Material using Moodle Learning Platform
Authors: Permana A H , Sekartaji A , Ambarwulan D
Published: November 2022

This study aims to develop a product as a formative test instrument that functions as a diagnostic test. This product aims to monitor student learning and provide ongoing feedback that instructors can use to improve their teaching and students’ learning. At the same time, it can be used as a tool that teachers can use to find out where students’ learning difficulties are so that the results can be used as a basis for follow-up. The research method used is Research and Development, which refers to the 4D development model. Tests were developed using the Moodle platform with three user groups: administrator, teacher, and students. The test developed was in the form of closed multiple choice with 20 questions and five answer choices. The questions were made using the cognitive level of Bloom’s taxonomy, starting from the remember level to evaluate. This formative test, which functions as a diagnostic test, has undergone a validation test involving media and material experts. Based on the validation, this development product is declared feasible to be used as an evaluation tool in Physics learning in measuring students’ learning outcomes and learning difficulties. After being tested on ten graders, especially the material on Newton’s Law, it is known that the factors that cause learning difficulties include low interest and motivation in learning physics and lack of mathematical ability. However, this research is still limited to knowing what causes learning difficulties. In this study, further research has not been carried out to find solutions to what teachers can do in dealing with these learning difficulties.
Development of Electronic Module Using TAI to Improve HOTS of High School Students in Fluid Dynamic Materials
Authors: Astra I M , Nurjanah I , Raihanati R , Fitri L H A
Published: November 2022

This research aims to produce independent learning materials in the form of an electronic module using a cooperative model the Assisted Individualization Team (TAI) type equipped with HOTS questions in a dynamic fluid material. The method used in this study is the development research with developmental stages of ADDIE (Analyze, Design, Development, Implementation, and Evaluation). The cooperative model type Assisted Individualization Team (TAI) has five learning stages: team formation, initial test, group learning, final test, and scoring. This electronic module is equipped with HOTS questions, where HOTS is a high-level thinking skill that includes three indicators, including analyzing skills (C4), evaluating (C5), and creating (C6). The results of the validation of the due diligence of the electronic module by media experts gained a score of 82.60%, the validation in the material aspect by the material experts gained score of 79.92%, the learning experts obtained 87.92%, and the calculation of n-gain test was 0.48 which means moderate category. These scores mean that the electronic physics module using cooperative model Team Assisted Individualization (TAI) type is equipped with HOTS questions in dynamic fluid materials as independent teaching material.
Determination of Planck’s Constant Using the Photoelectric Effect Experiment
Authors: Fitri U R , Ziveria M , Muhara I
Published: November 2022

Planck’s constant experiment has been carried out to determine the value of Planck’s constant using the regression analysis method. The steps are carried out using the scientific process outlined in the practical work steps. The specification of the experimental equipment uses the Planck constant experimental set with 12v/35w tungsten halogen light, 15v output, +-0.2% accuracy, 220V power requirement, 0.5A fuse rating and red, yellow 1, yellow 2, and red color filters, green and blue. Experiments using the concept of the photoelectric effect phenomenon began by irradiating metallic materials with light using a filter. The wavelength (635, 570, 540, 500, 460) nm is the light filter variation. The wavelength that hits the metal material is selected by placing a light filter on the light propagation path toward the metal material. So the light that passes through the filter is only light with a certain wavelength. After the metal material is irradiated by light with a certain wavelength, then the stopping potential voltage measurement is carried out on the metal material irradiated by light. From the variation of the light filter used, it is possible to calculate Planck’s constant using the regression method with the value obtained 6.26x1034. This value is very close to the actual Planck’s constant value which is 6.62x1034 so an error value is obtained 4.23%. With 95.77% accuracy, Planck’s constant value obtained from the calculation using the linear regression method can be said to be very close to the actual Planck’s constant value.
The Implementation of PBL Based on Blended Learning to Improve Students’ Creative Thinking in Physics Learning
Authors: Syukri M , Herliana F , Amalia R , Wahyuni S
Published: November 2022

This study aims to determine the improvement of students’ creative thinking skills after applying PBL based on blended learning in physics learning. This research is a quasi-experimental study with a non-equivalent control group design. The population of this study was all students of class XI SMAN 4 Wira Bangsa. The sampling technique used the purposive sampling method and obtained a research sample of 48 students who were divided into 2 groups, namely the experiment class and the control class. The data collection technique used in this research is a pretest-posttest using a creative thinking ability test instrument that measures 4 (four) indicators, namely fluency, flexibility, originality, and elaboration. The pretest-posttest data were analyzed using a t-test using an independent sample t-test assisted by SPSS. Based on the data from the t-test analysis, it was found that H0 was rejected, meaning that there was an increase in the creative thinking ability of students who applied PBL based on blended learning. The results of this study can be used as a reference for teachers, lecturers, and education practitioners to make Blended Learning-based PBL an effective learning model used to improve students’ creative thinking skills in learning physics.
Augmented Reality Video to Support Online Tutorial of Fundamental Physics Learning
Authors: Widiasih W , Johan H , Sipriyadi S , Johan S , Purwanto A.
Published: November 2022

This study aims to implement augmented reality videos in fundamental physics online tutorial activities to help students’ cognitive abilities on basic physics concepts. This study used a quasi-experimental method consisting of one experimental class and one control class. The research results show that the use of augmented reality technology in online tutorial activities can support students’ understanding of concepts. This can be seen from the average test results in the experimental class with a score of 8.6 being in the high category, and the average test results in the control class with a value of 7.1 being in the medium category. These results are also supported by student response data which states that using augmented reality videos can facilitate understanding concepts when studying independently. Thus, it can be concluded that implementing augmented reality videos in fundamental physics online tutorial activities can help students understand basic physics concepts
Profile of Students’ Critical Thinking Skills in Physics Learning: A Preliminary Study of Games Application Integrated Augmented Reality
Authors: Saphira H V , Rizki I A , Alfarizy Y , Saputri A D , Ramadani R , Suprapto N
Published: November 2022

The ability to think critically is included in one of the 21st-century skills students need to have. However, sometimes students have difficulty applying their critical thinking skills while facing a physics problem. Therefore, this research aims to determine students’ critical thinking skills in physics learning, especially in magnetic field subjects. This research method is a preliminary study with a sample of 58 high school students in Sidoarjo, East Java. Data collection techniques by sharing critical thinking skills tests and student response surveys. Then the data is analyzed using qualitative description to represent the research results. The research findings are that students have an average critical thinking ability score of 1.023 or are on low criteria. In more detail, six students have a moderate level of critical thinking ability, while 52 students have a low level. Therefore, the low ability to think critically becomes an urgent problem and needs to be solved immediately. Furthermore, there needs to be innovation to overcome these problems, one of which is to use the AR-integrated game application “Adventuring Physics.” These games are necessary to improve students’ critical thinking skills in physics, especially magnetic field subjects.
On the use of household expenditure surveys to monitor mismanaged plastic waste from food packaging in low- and middle-income countries
Authors: Wright Jim Allan , Damkjaer Simon , Vaisanen Heini , Adama-Tettey Quaranchie , Dzodzomenyo Mawuli , Hill Allan G , Okotto Lorna Grace , Okotto-Okotto Joseph , Shaw Peter
Published: November 2022

Background: substantial increases in plastic production have resulted in plastics proliferating of in the environment, with subsequent seabed plastic deposition and ingestion by marine fauna. There is an urgent need to monitor mismanaged plastic waste from household consumption. Household expenditure survey analysis has quantified mismanaged plastic waste generated from household packaged (bottled or bagged) water consumption, but not from consumption of other products. Methods: to evaluate whether household expenditure surveys can quantify mismanaged waste from other widely consumed commodities, we quantify mismanaged plastic waste from the domestic consumption of cooking oil alongside packaged water in urban Greater Accra, Ghana, and all cities nationally in Kenya using two household expenditure surveys. Results: household survey-derived estimates indicate packaged water consumption generates considerably more plastic waste than oil packaging in Greater Accra, whereas oil packaging generates more plastic waste than packaged water in urban Kenya. Conclusion: by successfully transferring a survey analysis protocol from packaged water to cooking oil, we conclude that there is ample potential for expenditure surveys to be used internationally to quantify mismanaged plastic waste from households. However, uncertainties affecting mismanaged waste estimates need to be accounted for.
Gas breakdown in radio-frequency field within MHz range: a review of the state of the art
Authors: JIANG Wei , WU Hao , WANG Zhijiang , YI Lin , ZHANG Ya
Published: November 2022

Low-temperature plasmas (LTPs) driven by 1–100 MHz radio-frequency (MRF) are essential for many industrial applications, and their breakdown characteristics are different to that of direct current (DC) breakdown. This review seeks to understand the state of the art of electric breakdown in the MRF field and provide references for related basic and applied research. We have given a brief history of research into MRF-driven breakdown, including Paschen curves, the corresponding discharge modes and parameter spaces, and the evolution of the parameters during the breakdown process. It is shown that the focus has been transferred from the breakdown voltage and V-I characteristics to the evolution of plasma parameters during the breakdown, both in experiments and simulations. It is shown that many fundamental and applied problems still need to be investigated, especially with the new global model and the incorporation of the external circuit model.
Relationship between surgical volume and outcomes in elective and acute cholecystectomy: nationwide, observational study
Authors: Blohm My , Sandblom Gabriel , Enochsson Lars , Hedberg Mats , Andersson Mikael Franko , Österberg Johanna
Published: November 2022

Background

High surgical volumes are attributed to improved quality of care, especially for extensive procedures. However, it remains unknown whether high-volume surgeons and hospitals have better results in gallstone surgery. The aim of this study was to investigate whether operative volume affects outcomes in cholecystectomies.

Methods

A registry-based cohort study was performed, based on the Swedish Registry of Gallstone Surgery. Cholecystectomies from 2006 to 2019 were included. Annual volumes for the surgeon and hospital were retrieved. All procedures were categorized into volume-based quartiles, with the highest group as reference. Low volume was defined as fewer than 20 operations per surgeon per year and fewer than 211 cholecystectomies per hospital per year. Differences in outcomes were analysed separately for elective and acute procedures.

Results

The analysis included 154 934 cholecystectomies. Of these, 101 221 (65.3 per cent) were elective and 53 713 (34.7 per cent) were acute procedures. Surgeons with low volumes had longer operating times (P < 0.001) and higher conversion rates in elective (OR 1.35; P = 0.023) and acute (OR 2.41; P < 0.001) operations. Low-volume surgeons also caused more bile duct injuries (OR 1.41; P = 0.033) and surgical complications (OR 1.15; P = 0.033) in elective surgery, but the results were not statistically significant for acute procedures. Low-volume hospitals had more bile duct injuries in both elective (OR 1.75; P = 0.002) and acute (OR 1.96; P = 0.003) operations, and a higher mortality rate after acute surgery (OR 2.53; P = 0.007).

Conclusion

This study has demonstrated that operative volumes influence outcomes in cholecystectomy. The results indicate that gallstone surgery should be performed by procedure-dedicated surgeons at hospitals with high volumes of this type of benign surgery.
Dysregulation of HNF1B/Clusterin axis enhances disease progression in a highly aggressive subset of pancreatic cancer patients
Authors: Yang Shouhui , Tang Wei , Azizian Azadeh , Gaedcke Jochen , Ströbel Philipp , Wang Limin , Cawley Helen , Ohara Yuuki , Valenzuela Paloma , Zhang Lin , Lal Trisha , Sinha Sanju , Rupin Eythan , Hanna Nader , Ghadimi B Michael , Hussain S Perwez
Published: November 2022

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy and is largely refractory to available treatments. Identifying key pathways associated with disease aggressiveness and therapeutic resistance may characterize candidate targets to improve patient outcomes. We used a strategy of examining the tumors from a subset of PDAC patient cohorts with the worst survival to understand the underlying mechanisms of aggressive disease progression and to identify candidate molecular targets with potential therapeutic significance. Non-negative matrix factorization (NMF) clustering, using gene expression profile, revealed three patient subsets. A 142-gene signature specific to the subset with the worst patient survival, predicted prognosis and stratified patients with significantly different survival in the test and validation cohorts. Gene-network and pathway analysis of the 142-gene signature revealed dysregulation of Clusterin (CLU) in the most aggressive patient subset in our patient cohort. Hepatocyte nuclear factor 1 b (HNF1B) positively regulated CLU, and a lower expression of HNF1B and CLU was associated with poor patient survival. Mechanistic and functional analyses revealed that CLU inhibits proliferation, 3D spheroid growth, invasiveness and epithelial-to-mesenchymal transition (EMT) in pancreatic cancer cell lines. Mechanistically, CLU enhanced proteasomal degradation of EMT-regulator, ZEB1. In addition, orthotopic transplant of CLU-expressing pancreatic cancer cells reduced tumor growth in mice. Furthermore, CLU enhanced sensitivity of pancreatic cancer cells representing aggressive patient subset, to the chemotherapeutic drug gemcitabine. Taken together, HNF1B/CLU axis negatively regulates pancreatic cancer progression and may potentially be useful in designing novel strategies to attenuate disease progression in PDAC patients.
Clinical features, diagnosis, and management of pembrolizumab-induced myasthenia gravis
Authors: Zhao Shaoli , Zhou Yulu , Sun Wei , Li Zuojun , Wang Chunjiang
Published: November 2022

Myasthenia gravis (MG) is a rare but life-threatening adverse event with pembrolizumab. What is known about pembrolizumab-induced MG is largely based on case reports. This analysis collected pembrolizumab-induced MG cases from Chinese and English databases published from September 1, 2014, to June 30, 2022. Demographic and clinical information of the patients, management, and outcome data were collected and analyzed. Sixty-five patients with a median age of 73 years (range 30–86), including 43 male patients (66.2%), were included. Eight patients (12.3%) with prior MG experienced worsening symptoms after receiving pembrolizumab. The median time to the onset of MG was four weeks (range 0.7–27). The most common symptoms were ptosis (81.5%, 53 patients), diplopia (50.8%, 33 patients), dyspnea (44.6%, 29 patients), trunk or peripheral weakness (43.1%, 28 patients), and dysphagia (30.8%, 20 patients). Concurrent myositis and myocarditis occurred in 13 (20.0%) and 17 patients (26.2%). Pembrolizumab was discontinued in 63 patients (96.9%). Forty-four patients (67.7%) received combination therapies based on steroids (intravenous immune globulin, plasmapheresis, or immunosuppressants). Twenty-seven patients (41.5%) had symptoms completely recovered. Fourteen patients (21.5%) died from immunotoxicity or primary cancers. Clinicians should consider the possibility of pembrolizumab-induced MG, especially during the first eight weeks of therapy. Patients should be treated as early as possible, regardless of the severity of the initial symptoms.
Assemblage of Ceutorhynchinae Weevils Associated With Brassicaceae in Quebec (Canada) Agroecosystems
Authors: Desroches Claudine , Bouchard Patrice , Labrie Geneviève , Lucas Eric
Published: November 2022

Ceutorhynchinae Gistel (Coleoptera: Curculionidae) are a highly diverse phytophagous group of weevils in which the most species rich genus, Ceutorhynchus Germar (Coleoptera: Curculionidae), is mainly associated with Brassicaceae. Some Ceutorhynchinae, such as the invasive cabbage seedpod weevil (CSW), Ceutorhynchus obstrictus (Marsham), are important pests of cultivated Brassicaceae, and others are natural enemies of weeds and potential biological control agents. This study aims to characterize Ceutorhynchinae assemblages in canola growing regions of Quebec. Ceutorhynchinae were sampled in areas adjacent to canola fields or other crops in six administrative regions of Quebec during the summers of 2019 and 2020. A total of 25 Ceutorhynchinae species were collected and identified. Canonical analysis and multivariate regression tree analysis revealed that the assemblage of Ceutorhynchinae varied regionally and was either dominated by the invasive canola pest CSW or by the native weevil Ceutorhynchus neglectus Blatchley. Our results also highlighted new biological associations between weevils and Brassicaceae like the CSW with the yellow rocket, Barbarea vulgaris R. Br., native Ceutorhynchus pauxillus Dietz with common pepper grass, Lepidium densiflorum, and native Ceutorhynchus semirufus LeConte with Pennsylvania bittercress, Cardamine pensylvanica Muhl. This study also provides a useful tool to find new biological control agents against Brassicaceae weeds and to monitor the abundance and diversity of this taxon and provide baseline data to assess future impacts of exotic parasitoids of CSW on native weevils.
Digital multimodal composing in English language teaching
Authors: Kessler Matt , Marino Francesca
Published: November 2022

In this series, we explore technology-related themes and topics. The series aims to discuss and demystify what may be new areas for some readers and to consider their relevance for English language teachers.
Mitochondrial genome maintenance—the kinetoplast story
Authors: Amodeo Simona , Bregy Irina , Ochsenreiter Torsten
Published: November 2022

Mitochondrial DNA replication is an essential process in most eukaryotes. Similar to the diversity in mitochondrial genome size and organization in the different eukaryotic supergroups, there is considerable diversity in the replication process of the mitochondrial DNA. In this review, we summarize the current knowledge of mitochondrial DNA replication and the associated factors in trypanosomes with a focus on Trypanosoma brucei, and provide a new model of minicircle replication for this protozoan parasite. The model assumes the mitochondrial DNA (kinetoplast DNA, kDNA) of T. brucei to be loosely diploid in nature and the replication of the genome to occur at two replication centers at the opposing ends of the kDNA disc (also known as antipodal sites, APS). The new model is consistent with the localization of most replication factors and in contrast to the current model, it does not require the assumption of an unknown sorting and transport complex moving freshly replicated DNA to the APS. In combination with the previously proposed sexual stages of the parasite in the insect vector, the new model provides a mechanism for maintenance of the mitochondrial genetic diversity.
Full-waveform inversion method for tunnel seismic forward prospecting
Authors: Liu Bin , Gong Zhifei , Zhang Fengkai , Xu Xinji , Zhao Yang , Chen Lei
Published: November 2022

During tunnel construction, accurately ascertaining the adverse geological condition in front of the tunnel face is essential to ensure construction safety and decrease economic loss. As an accurate wave velocity modelling method, seismic full-waveform inversion (FWI) still faces many difficulties when applied in a tunnel observation environment because of fewer observation data and smaller offset than ground seismic detection. This paper analysed the FWI for tunnel active seismic forward prospecting with a single shot. We adopted the N-order time integral wavefield and normalized integration objective function method to improve the stability and reduce the dependence of FWI on the initial model. Based on two assumptions on the wave velocity distribution in the tunnel, we proposed a 1-D velocity structure correction method to reduce the multiplicity of inversion. Then the improved tunnel FWI method based on these two inversion strategies was applied to a synthetic model with a rectangular anomaly and a lithology interface, verifying the method's effectiveness. Based on typical adverse geological bodies during tunnelling, three additional adverse geological models were built and verified the reliability of the methods in tunnel detection environments. There are still some false anomalies interference in the inversion results of the synthetic models from the inversion results. However, these problems are acceptable in limited tunnel observation space. Then the method was applied in a field example in the Yinsong water supply project in Jilin Province, China, and verified the effect on field data. Finally, the influence of the shot number on the inversion effect and the method's robustness are discussed.