bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical simulations of solid cerium ejecta transporting in vacuum and in non-reactive and reactive gases
Authors: Lyu Sijia , Shi Xiaofeng , Han Dongyan , Ma Zongqiang , Ma Dongjun , Sun Zhiyuan , Sun Haiquan , Wang Pei
Published: May 2023

When a shock wave impacts a roughened metal/gas interface, metal ejecta particles emit and transport in the gas. The exchanges of momentum and energy between ejecta particles and the gas occur. If active metal particles transport in the reactive gas, the heat released by a chemical reaction could change these exchanges. In this paper, we use numerical simulations to study solid cerium ejecta transporting in a vacuum, and in non-reactive and reactive gases. In vacuum, the emitted ejecta could self-similarly expand neglecting the particle interaction. In the non-reactive gas (He), ejecta particles slow down by the gas resistance and have the exchanges of momentum and energy with the gas. In the reactive gas (D2), the ejecta particles also slow down. The exothermic reaction could induce the temperature rise of the ejecta and the gas, which could induce changes in physical property values of the gas after the shock wave and the velocity of the shock wave. The numerical result shows that the maximum temperature of the ejecta may appear in the middle of the mixture zone, which may result from the ejecta temperature being controlled by two competitive effects. Furthermore, the maximum ejecta temperature increases rapidly in the beginning and then becomes steady. Finally, the ejecta with a different initial size distribution is investigated. The ejecta with a smaller maximum size has a larger maximum particle temperature, a larger gas temperature after the shock wave, and a larger chemical reaction function of the ejecta at the same moment.
Corrugation geometry effect on jet mixing
Authors: Rathakrishnan Ethirajan
Published: May 2023

An experimental investigation was carried out to assess the mixing promoting efficiency of rectangular, semicircular, and triangular corrugations at the edges of rectangular tabs. Mixing promoting capability of two rectangular tabs with aspect ratio of 1.0, 1.5, and 2.0, with rectangular, semicircular, and triangular corrugations over their edges, located diametrically opposite at the exit of a convergent–divergent Mach 1.73 nozzle was studied. Pressure measurements and optical flow visualization were carried out. The nozzle pressure ratios (NPRs) studied were 4, 5, 6, 7 and 8, in order to cover different levels of expansion at the nozzle exit. At NPR 4, Mach 1.73 nozzle is overexpanded, with about 23% adverse pressure gradient. At NPR 5, the adverse pressure gradient is just 3%. At NPR 6, 7, and 8, the jet is underexpanded with favorable pressure gradients of 16%, 36%, and 55%, respectively. The corrugated tabs were found to be efficient mixing promoters, leading to shorter core and weaker shocks in the core than the uncontrolled jet. The mixing effectiveness of the corrugated tab is found to increase with increase in NPR. The core length reduction associated with all the corrugations is found to increase with increase in tab aspect ratio. At the almost correctly expanded state, for aspect ratio 1, rectangular corrugation is found to be the most efficient mixing promoter, causing a core length reduction of almost 100%, followed by the triangular and semicircular corrugations, leading to a 77% and 73% reduction, respectively. For aspect ratios 1.5 and 2.0, triangular corrugation is found to be the most efficient mixing promoter, causing a core length reduction of almost 100%, followed by the rectangular and semicircular corrugations. The shadowgraph images of the controlled and uncontrolled jets demonstrate the effectiveness of the corrugated tabs in weakening the waves in the jet core.
Three-dimensional simulation of a gas-centered swirl coaxial injector spray under pulsation conditions
Authors: Gao Yuchao , Chu Wei , Kang Jinxin , Jiang Chuanjin , Su Lingyu , Tong Yiheng , Lin Wei
Published: May 2023

Based on steady-state experiments, a three-dimensional (3D) simulation study under pulsation conditions was carried out. This was performed to study the effect of pulsation of the supply system on the atomization characteristics of a gas-centered swirl coaxial injector. The results indicated that the spray shape resembled a pagoda when the Klystron effect occurred. When the low-frequency pulsation (200 Hz) was applied to the liquid inlet, the peak of the exit pressure was close to the trough of the inlet mass flow rate. Meanwhile, the exit mass flow rate and pressure were approximately sinusoidal. There was no significant lag effect in the response of the exit mass flow rate to the inlet mass flow rate but with a small sawtooth-like oscillation. Increasing the amplitude of the liquid inlet disturbance amplified the exit mass flow rate fluctuation, which was greater than the set amplitude of the inlet pulsation. The dominant frequency of the injector exit mass flow rate and pressure variation was significantly less than the inlet pulsation frequency when the frequency of the liquid inlet pulsation was increased to 1000 Hz. This was due to the low-pass filtering effect of the annular slit. There was no significant change in the overall spray morphology for the gas inlet pulsation. By applying the same amplitude and frequency of pulsation to the gas and liquid inlets of the injector, the pulsation of the liquid inlet had a stronger effect on the injector exit spray than that of the gas inlet.
Ion migration induced bipolar diode effect and ferroelectricity modulation in CuInP2S6
Authors: Rong Dongke , Tian Cheng , Xing Jie , Jin Qiao , Ma Fangyuan , Liu Guozhen , Qiu Jie , Zhao Changchun , Hao Huiying , Dong Jingjing , Liu Hao , Shi Youguo , Guo Er-Jia
Published: May 2023

The coupling between ferroelectricity and ion conductivity always presents unique physical and chemical properties, making it crucial to understand their correlation for the development of advanced functional devices. CuInP2S6 (CIPS), a van der Waals “ferroionic” material, serves as an excellent platform to investigate their intercoupling. In this study, we observe a bipolar diode-like rectification behavior in a vertical Pt/CIPS/In capacitor by controlling the migration of Cu ions. The non-uniform distribution of mobile Cu ions is coupled with ferroelectricity, resulting in a switchable imprint field and an enhanced saturation polarization about 12 μC/cm2 in CIPS. Additionally, CIPS exhibits a significant photovoltaic response due to its robust built-in electric field caused by the unbalanced distribution of Cu ions. This work demonstrates a controllable Cu ions migration and its manipulation on the electrical transport and ferroelectricity in CIPS. The dynamically tunable bipolar diode effect, closely coupled with ferroelectricity in CIPS, has promising prospects in self-powered photodetectors, memristors, and neuromorphic computing.
Optimal predictive guidance law based on guidance law identification using variable structure interactive multiple guidance law model
Authors: Chen Weiyi , He Fan , Dong Haidi
Published: May 2023

For a defender protecting a target from an incoming high-maneuvering homing missile, an Optimal Predictive Guidance Law (OPGL) is proposed based on a guidance law identification algorithm. First, a guidance law identification algorithm based on the Interactive Multiple Guidance law Model (IMGM) is designed. IMGM uses multiple sub-filters for parallel processing, and there is interaction between the inputs and outputs of the sub-filters. Second, the VSIMGM algorithm is further designed based on the IMGM algorithm. In this algorithm, a new guidance law model subset is constructed based on the original guidance law model set. By reducing the number of models, the model error is reduced, and the identification probability of the guidance law model is improved. Then, based on the identification result of the identification algorithm, the OPGL is given by using the variational method through the steps of linearizing the kinematic model and reducing the order of state equation. The OPGL reduces the overload requirement of the defender and improves interception accuracy without assuming the maneuver mode of a homing missile. Finally, the effectiveness of the proposed OPGL and guidance law identification algorithm based on VSIMGM is demonstrated using numerical simulation. Compared with the guidance law identification algorithm based on MMAE and IMGM, the guidance law identification algorithm based on VSIMGM can quickly, stably, and accurately identify the guidance law. In addition, based on the guidance law identification results of the homing missile, compared with proportional navigation, augmented proportional navigation, differential game guidance (DGG), and sliding mode guidance (SMG), OPGL can reduce the required overload of the missile and achieve accurate interception.
A delta barrier in a well and the exact time evolution of its eigenstates
Authors: Jensen Kevin L. , Riga Jeanne , Shabaev Andrew , Osofsky Michael , Prestigiacomo Joseph C.
Published: May 2023

The analytic nature of the transmission coefficient for a δ-function barrier makes it a useful tool to examine a variety of technologically important applications, such as photoemission from semiconductors with an alkali coating, the examination of tunneling times for wave packets incident on a barrier, and for parameterizing tunneling through the narrow barrier of a normal-superconducting point contact. The analytic model of a δ-function barrier inside a confining well is extended to the finite height and width rectangular barrier (a delta-function sequence). Methods to exactly evaluate the eigenstates are given and their dependencies are examined. The time evolution of a superposition of the lowest eigenstates is considered for barriers having comparable Gamow tunneling factors so as to quantify the impact of barrier height and shape on time evolution in a simple and exact system and, therefore, serve as a proxy for tunneling time. Last, density profiles and associated quantum potentials are examined for coupled wells to show changes induced by weaker and wider barriers.
Generalized magnetostatic target field method for shielded magnetic field coils in a separable coordinate system
Authors: Lee Seung-Kyun , Schenck John
Published: May 2023

A theoretical method is described to analytically calculate a pair of surface current densities, which produce a desired static magnetic field in one region of the space and zero magnetic field in another. The analysis is based on the known relationship between a surface current density and a stream function, the equivalence of stream functions and surface magnetic dipole density, and the scalar potential representation of the associated magnetic field in free space. From these relations, we formulate the magnetostatic problem, which is often treated as a vector field problem, as a scalar field problem in which a two-dimensional scalar field (stream function) is related to a three-dimensional one (magnetic scalar potential) via the differentiation of the electrostatic Green's function 1/|r–rs|. It is shown that, in a coordinate system in which a separated form of the Green's function exists (separable coordinate system), there exists a simple relationship between a harmonic component of a stream function and a harmonic component of the magnetic scalar potential. The method is applied to calculate idealized surface current patterns for actively shielded, linear gradient field coils in the Cartesian, cylindrical, and spherical coordinates.
Decomposition of methanol-d4 on a thin film of Al2O3/NiAl(100) under near-ambient-pressure conditions
Authors: Liao Guan-Jr , Hsueh Wen-Hao , Yen Yu-Hsiang , Shih Yi-Chan , Wang Chia-Hsin , Wang Jeng-Han , Luo Meng-Fan
Published: May 2023

We have studied the decomposition of methanol-d4 on thin film Al2O3/NiAl(100) under near-ambient-pressure conditions, with varied surface-probe techniques and calculations based on density-functional theory. Methanol-d4 neither adsorbed nor reacted on Al2O3/NiAl(100) at 400 K under ultrahigh vacuum conditions, whereas they dehydrogenated, largely to methoxy-d3 (CD3O*, * denoting adsorbates) and formaldehyde-d2 (CD2O*), on the surface when the methanol-d4 partial pressure was increased to 10−3 mbar and above. The dehydrogenation was facilitated by hydroxyl (OH* or OD*) from the dissociation of little co-adsorbed water; a small fraction of CD2O* interacted further with OH* (OD*) to form, via intermediate CD2OOH* (CD2OOD*), formic acid (DCOOH* or DCOOD*). A few surface carbonates were also yielded, likely on the defect sites of Al2O3/NiAl(100). The results suggest that alumina not only supports metal clusters but also participates in reactions under realistic catalytic conditions. One may consider accordingly the multiple functions of alumina while designing ideal catalysts.
First-principles study on the conventional superconductivity of N-doped fcc-LuH3
Authors: Huo Zihao , Duan Defang , Ma Tiancheng , Zhang Zihan , Jiang Qiwen , An Decheng , Song Hao , Tian Fubo , Cui Tian
Published: May 2023

Recently, room-temperature superconductivity has been reported in a nitrogen-doped lutetium hydride at near-ambient pressure [Dasenbrock-Gammon et al., Nature 615, 244 (2023)]. The superconducting properties might arise from Fm3̄m-LuH3−δNε. Here, we systematically study the phase diagram of Lu–N–H at 1 GPa using first-principles calculations, and we do not find any thermodynamically stable ternary compounds. In addition, we calculate the dynamic stability and superconducting properties of N-doped Fm3̄m-LuH3 using the virtual crystal approximation (VCA) and the supercell method. The R3m-Lu2H5N predicted using the supercell method could be dynamically stable at 50 GPa, with a Tc of 27 K. According to the VCA method, the highest Tc is 22 K, obtained with 1% N-doping at 30 GPa. Moreover, the doping of nitrogen atoms into Fm3̄m-LuH3 slightly enhances Tc, but raises the dynamically stable pressure. Our theoretical results show that the Tc values of N-doped LuH3 estimated using the Allen–Dynes-modified McMillan equation are much lower than room temperature.
The hypothermic nature of fungi
Authors: Cordero Radames J. B. , Mattoon Ellie Rose , Ramos Zulymar , Casadevall Arturo
Published: May 2023

Fungi play essential roles in global health, ecology, and economy, but their thermal biology is relatively unexplored. Mushrooms, the fruiting body of mycelium, were previously noticed to be colder than surrounding air through evaporative cooling. Here, we confirm those observations using infrared thermography and report that this hypothermic state is also observed in mold and yeast colonies. The relatively colder temperature of yeasts and molds is also mediated via evaporative cooling and associated with the accumulation of condensed water droplets on plate lids above colonies. The colonies appear coldest at their center and the surrounding agar appears warmest near the colony edges. The analysis of cultivatedPleurotus ostreatusmushrooms revealed that the hypothermic feature of mushrooms can be observed throughout the whole fruiting process and at the level of mycelium. The mushroom’s hymenium was coldest, and different areas of the mushroom appear to dissipate heat differently. We also constructed a mushroom-based air-cooling prototype system capable of passively reducing the temperature of a semiclosed compartment by approximately 10 °C in 25 min. These findings suggest that the fungal kingdom is characteristically cold. Since fungi make up approximately 2% of Earth’s biomass, their evapotranspiration may contribute to cooler temperatures in local environments.
Models and potentials in hadron spectroscopy
Authors: M Sreelakshmi , Ranjan Akhilesh
Published: May 2023

In the past twenty years, hadron spectroscopy has made immense progress. Experimental facilities have observed different multiquark states during these years. There are different models and phenomenological potentials to study the nature of interquark interaction. In this work, we have reviewed different quark potentials and models used in hadron spectroscopy.
Asevolution: a relativistic N-body implementation of the (a)symmetron
Authors: Christiansen Øyvind , Hassani Farbod , Jalilvand Mona , Mota David F.
Published: May 2023

We present asevolution, a cosmological N-body code developed based on gevolution, which consistently solves for the (a)symmetron scalar field and metric potentials within the weak-field approximation. In asevolution, the scalar field is dynamic and can form non-linear structures.
A cubic term is added in the symmetron potential to make the symmetry-broken vacuum expectation values different, which is motivated by observational tensions in the late-time universe. To study the effects of the scalar field dynamics, we also implement a constraint solver making use of the quasi-static approximation, and provide options for evaluating the background evolution, including using the full energy density averaged over the simulation box within the Friedmann equation. The asevolution code is validated by comparison with the Newtonian N-body code ISIS that makes use of the quasi-static approximation. There is found a very small effect of including relativistic and weak-field corrections in our small test simulations; it is seen that for small masses, the field is dynamic
and can not be accurately solved for using
the quasi-static approximation;
and we observe
the formation of unstable domain walls and demonstrate a useful way to identify them within the code. A first consideration indicates that the domain walls are more unstable in the asymmetron scenario.
Deep Multimodal Networks for M-type Star Classification with Paired Spectrum and Photometric Image
Authors: Gao Jialin , Chen Jianyu , Wei Jiaqi , Jiang Bin , Luo A-Li
Published: May 2023

Traditional stellar classification methods include spectral and photometric classification separately. Although satisfactory results can be achieved, the accuracy could be improved. In this paper, we pioneer a novel approach to deeply fuse the spectra and photometric images of the sources in an advanced multimodal network to enhance the model’s discriminatory ability. We use Transformer as the fusion module and apply a spectrum–image contrastive loss function to enhance the consistency of the spectrum and photometric image of the same source in two different feature spaces. We perform M-type stellar subtype classification on two data sets with high and low signal-to-noise ratio (S/N) spectra and corresponding photometric images, and the F1-score achieves 95.65% and 90.84%, respectively. In our experiments, we prove that our model effectively utilizes the information from photometric images and is more accurate than advanced spectrum and photometric image classifiers. Our contributions can be summarized as follows: (1) We propose an innovative idea for stellar classification that allows the model to simultaneously consider information from spectra and photometric images. (2) We discover the challenge of fusing low-S/N spectra and photometric images in the Transformer and provide a solution. (3) The effectiveness of Transformer for spectral classification is discussed for the first time and will inspire more Transformer-based spectral classification models.
Ammonia production in a dual crossed atom beam experiment
Authors: Zaplotnik R. , Drenik A. , Vesel A. , Mozetič M.
Published: May 2023

Production of ammonia by surface reactions of H and N atoms on surfaces not wetted by partially ionized plasma may represent an important technological issue in fusion reactors where puffing nitrogen is employed to cool plasma in the divertor region. The H and N atoms are likely to interact on such surfaces forming NH3 molecules. The interaction efficiency was studied in a laboratory setup consisting of two separate sources of either N or H atoms. Both sources enabled experiments with atoms at room temperature in the range of H-atom density of the order of 1021 m−3 and N-atom density of the order of 1020 m−3. The production of ammonia was measured with a calibrated residual gas analyser. The production depended on the fluxes of both atoms onto the surface of selected materials. As a general rule, the higher H-atom flux at a constant N-atom flux caused an increase in ammonia production. The highest efficiency of up to 50% was found for nickel. It was up to 30% for tungsten, whereas for P92 alloy, it was up to about 20%. The accuracy of these results is within about ±20% of the measured values. Methods for suppressing ammonia formation in fusion reactors will have to be invented in order to enable appropriate long-term operation.
Analysis and evaluation study of retaining wall structures in a building project in South Jakarta
Authors: Jatnika Raihan Alifandika , Gede Mahardika Susila I
Published: May 2023

Retaining wall type contiguous pile is a structure that serves to hold and stabilize the soil in certain soil conditions. Retaining walls can be deformed by various factors. This research on retaining walls compares the deformation results between the actual data, the finite element method with the Mohr - Coulomb, Soft Soil and Hardening Soil parameters, and find the safety factor based on SNI Geotechnical 8460:2017. The result of this research is that the deformation value of Mohr - Coulomb modelling is closer than the actual value in the field, followed by the modelling of Soft Soil & Hardening Soil, Soft Soil & Mohr-Coulomb, and Hardening Soil. This difference occurs because there are differences in the correlation approach and the type of undrained type used. It was found that the Mohr - Coulomb parameter is better than the other parameters with a deformation result of 24.5 mm with a safety factor of 1.675 which is close to the actual data.
Sustainable traffic management solution for unsignalized Kelapa Gading Roundabout
Authors: Shahkaflie Muhammad , Prahara Eduardi , Rahardhani Audry Farrel S.
Published: May 2023

Jalan Boulevard Raya, Kelapa Gading. The flow of heavy traffic on every arm, causes congestion and a high degree of saturation at every rush hour in the morning and afternoon at this unsignalized roundabout. The calculation of the roundabout capacity is regulated in the Indonesia Road Capacity Manual (IHCM) 1997. Observation data in the form of geometric conditions, traffic volume and environmental conditions in the calculation. The performance of the Kelapa Gading roundabout can be categorized as not good the degree of saturation (DS) can come up more than 0.75. Simulation was carried out on Vissim to sustainable traffic management solution and decrease the DS for driver convenience.
Application of direct analysis method on the long span steel structures
Authors: Erizal Muhamad Iqbal , Suwondo Riza , Suangga Made
Published: May 2023

Along with development of the method for calculating the stability of steel structures, the direct analysis method is one of the recommended methods. This method is adopted by many design codes including AISC 360 and SNI 1729:2020. The direct analysis method has been considered as the primary method since it can overcome the limitations of the previous method, known as the effective length method. The main objective of this study is to understand the application of the direct analysis method on the long span steel structures. This research considers the effect of building height, earthquake loads, and gravity loads on the steel structure stability. The results show that the direct analysis method is a simpler and more efficient method since it has taken into account the second-order effect and has a smaller stress ratio value compared to the Effective Length Method. Therefore, the direct analysis method can be used as a recommendation method for calculating the stability of steel structures.
Analysis of Sustainable Online Fish Auction Services Using Process Chain Network Diagram
Authors: Abdallah B N , Redi A A N P , Oktaviani A N , Ulfa E S , Muqimuddin  , Sartika W , Triajie H , Aslan L O M
Published: May 2023

Information technology rapidly increases by time and things are becoming more challenging nowadays, one of which is by using an e-commerce platform that makes perishable products, including fishery products become one of the commodities that attract market attention. However, due to the long and complex supply chain of fishery products, there are many problems faced by suppliers and customers of this perishable product. The discussion using the process-chain network method in this study aims to reduce supply chain complexity through digital platforms. An online digital auction system can give customers direct access to the upstream of the supply chain and can expand the market. The method used business process modelling using the PCN (Process Chain Network) concept through literature study to obtain a business model that is easily understood by all parties and data collection through interviews. The data that has been obtained is analysed by procedures and is described in the form of a diagram. The result is obtained an online fish auction system model in the form of a business process. Thus, this analysis is important for further research in designing Standard Operating Procedures (SOP) of online fish auctions to help establish a sustainable online fish auction.
Sustainable design strategy through upcycling waste wood material and creating a digital marketplace for micro crafters community
Authors: Fajarwati Ade Ariyani Sari , Wulandari Anak Agung Ayu , Caroline Octaviana Sylvia , Ruki Ulli Aulia , Fanthi Reno , Fathoni Ahmad Faisal Choiril Anam
Published: May 2023

Design should not only improve human life, but also should have a share sustainable movement through circular economy concept that are restorative and regenerative by design to keep products, components, and materials at their highest utility and value. Not only designing environmentally sustainable interior products, but a marketing tool is also proposed to bridge the gap between these micro crafters and a wider market. The study aims to create integrated concepts that encourage circular economy through designing environmentally sustainable interior products and providing a digital marketplace as means for micro crafters to market their products in order to bridge the gap between micro crafters. Not only to give sustainable and economic impact, but this study will also have social impact especially for the micro crafters in Jepara with their generations of crafters. The result of this study is prototypes of three sustainable interior products made of waste wood and a digital marketplace concept to help market the products.
The Usage of Dried Breadfruit Leaves as Particle Board Material
Authors: Kamara Laura Valencia , Gandawijaya R.Asep Ahadiat
Published: May 2023

Breadfruit plant also known as Artocarpus altilis, is a plant that lives in tropical climate. This plant has various advantages neither for consumption nor health. This makes some people interested in growing breadfruit plants. However, most people still do not know breadfruit leaves can be beneficial, so it often ends up as organic waste or compost. From the problem that has been mentioned, dried breadfruit leaves have the potential to be used for other things such as particle board material. Particle board is made from wood chips and adhesive such as resin that are processed at high temperature also pressed until it become a board. The theory and method that are used in these experiments is quantitative to know whether dried breadfruit leaves have a good quality as particle board material or not. The experiments use different variables and will be compared to determine which experiments have the best quality. With this experiments method, the expected result is that dried breadfruit leaves can be used as particle board material with a good strength and density.
Development of ready-to-eat (RTE) liwet rice with corn analog rice substitution as an alternative food in emergency conditions
Authors: Rubby M , Oktarina R , Amrinola W
Published: May 2023

This research aims to develop ready-to-eat (RTE) rice based on local food, namely liwet rice which is substituted with corn analog rice. This RTE rice is intended for food supplies in disaster emergencies and still contributes to the food diversification program. The RTE liwet rice production carried out in this study was by using the retort process. The retort process was carried out using an autoclave at 121 0C for 15 minutes and used retort pouch packaging. The RTE liwet rice in this study made used five formulations of corn analog rice substitution, namely 0%, 20%, 30%, 40%, and 50%. The resulting liwet rice was then analyzed for its physicochemical and organoleptic characteristics. The results showed that the substitution of corn analog rice had a significant effect on the proximate content and physical properties (texture and color) of the liwet rice produced but did not significantly affect the pH and organoleptic characteristics. The best formula in this study was obtained in the 30% substitution of corn analog rice.
Field emission properties of nano-tendril bundles formed via helium plasma exposure with various additional impurity gases
Authors: Zhang Rongshi , Kajita Shin , Hwangbo Dogyun , Tanaka Hirohiko , Feng Shuangyuan , Ohno Noriyasu
Published: May 2023

Nano-tendril bundles (NTBs) were formed on tungsten via helium (He) plasma exposure with various additional impurity gases, such as neon (Ne), nitrogen (N2), and argon (Ar). The sizes of the NTBs showed different distributions with different additional impurity gases. The field emission property of the NTBs formed with various additional impurity gases was measured. The field-emission property was significantly affected by the morphology of the NTBs, especially the tips of the fibers. In the Ne- and Ar-seeded cases, the NTBs were formed with sharp tips, and the onset electric field for field emission was ∼1 kV mm−1 for all the NTB samples. The Ne-seeded samples showed the most rapid increase in the emission current. In the N2-seeded case, two types of NTBs were formed. The NTBs were formed with sharp tips when the ratio of N2 impurity gas was 2.1%. With an increase in the ratio to 3.0% or higher, the fibers of the NTBs became thicker and the tips became rounder. In the Fowler–Nordheim (F-N) plot analysis, the field enhancement factors were approximately 6000–7000 without significant differences, for all NTBs with sharp tips. NTBs with round tips showed totally different field emission property, as the emission current was only several μA, which is one-tenth of that for the other samples. This suggests that the local morphology of NTBs, especially the geometrical shape of the tips, and not the general size of NTBs, is the main factor in determining the field emission property of NTBs.
Macroscopic tensile properties of AlxCoCrCuFeNi (x = 0.3 and 1) before and after heat treatment
Authors: Kiyomiya Kai , Arai Yutaro , Inoue Ryo
Published: May 2023

The relationship between morphology (grain-size order) and mechanical properties of AlxCoCrCuFeNi (x = 0.3 and 1) was evaluated. Both alloys were prepared using the arc-melting method. Crystal structures with x = 0.3, face-centered cubic (FCC), and body-centered cubic (BCC) structures were observed for x = 1, the typical crystal structures of AlxCoCrCuFeNi. The alloys prepared via arc melting exhibited two different microstructures: a Cu-rich region (area I) and an equiatomic region (area II). Microstructures of the as-fabricated specimen were homogenized through heat treatment at 600 and 1000 °C for 5 h. Although the homogenization of the microstructure proceeded, areas I and II remained after the heat treatment. In particular, the area I composition was inconsistent with the predicted phase diagram. Tensile tests for these alloys revealed that the tensile strength of x = 1 (∼310–1100 MPa) is higher than that of x = 0.3 (∼320–660 MPa), whereas the fracture strain of x = 1 (∼0.03–0.09) is lower than that of x = 0.3 (∼0.06–0.26). These results indicate that the increase in Al content caused an increase in strength and brittle fracture because it also caused an increase in the formation of the BCC and B2 phases, which required higher stresses for the movement of dislocations than the FCC phase. Because the tensile properties of AlxCoCrCuFeNi are comparable to those of conventional alloys, such as Ti alloys and steels, a design with a moderate composition for stronger and tougher AlxCoCrCuFeNi is required to apply high entropy alloys to structural materials.
Stability of standing waves for a generalized Benney-Roskes system
Authors: Quintero José
Published: May 2023

We analyze the orbital stability of standing waves for a generalized Benney-Roskes system in spatial dimensions

N
=
2

N=2

,

3
3

. We establish stability of standing waves under certain conditions by reducing the system to a single nonlinear (nonlocal) Schrödinger equation, using the variational characterization of standing waves and a convexity argument.
Push-Through Filtration of Emulsified Adipose Tissue Over a 500-µm Mesh Significantly Reduces the Amount of Stromal Vascular Fraction and Mesenchymal Stem Cells
Authors: Ramaut Lisa , Moonen Linde , Laeremans Thessa , Aerts Joeri L , Geeroms Maxim , Hamdi Moustapha
Published: May 2023

Background

Mechanical isolation of the stromal vascular fraction (SVF) separates the stromal component from the parenchymal cells. Emulsification is currently the most commonly used disaggregation method and is effective in disrupting adipocytes and fragmenting the extracellular matrix (ECM). Subsequent push-through filtration of emulsified adipose tissue removes parts of the ECM that are not sufficiently micronized, thereby further liquifying the tissue.

Objectives

The aim of this study was to investigate whether filtration over a 500-µm mesh filter might affect the SVF and adipose-derived mesenchymal stem cell (MSC) quantity in emulsified lipoaspirate samples by removing ECM fragments.

Methods

Eleven lipoaspirate samples from healthy nonobese women were harvested and emulsified in 30 passes. One-half of the sample was filtered through a 500-µm mesh filter and the other half was left unfiltered. Paired samples were processed and analyzed by flow cytometry to identify cellular viability, and SVF and MSC yield.

Results

Push-through filtration reduced the number of SVF cells by a mean [standard deviation] of 39.65% [5.67%] (P < .01). It also significantly reduced MSC counts by 48.28% [6.72%] (P < .01). Filtration did not significantly affect viability (P = .118).

Conclusions

Retention of fibrous remnants by push-through filters removed ECM containing the SVF and MSCs from emulsified lipoaspirates. Processing methods should aim either to further micronize the lipoaspirate before filtering or not to filter the samples at all, to preserve both the cellular component carried within the ECM and the inductive properties of the ECM itself.
Performance of ChatGPT on the Plastic Surgery Inservice Training Examination
Authors: Gupta Rohun , Herzog Isabel , Park John B , Weisberger Joseph , Firouzbakht Peter , Ocon Vanessa , Chao John , Lee Edward S , Mailey Brian A
Published: May 2023

Background

Developed originally as a tool for resident self-evaluation, the Plastic Surgery Inservice Training Examination (PSITE) has become a standardized tool adopted by Plastic Surgery residency programs. The introduction of large language models (LLMs), such as ChatGPT (OpenAI, San Francisco, CA), has demonstrated the potential to help propel the field of Plastic Surgery.

Objectives

The authors of this study wanted to assess whether or not ChatGPT could be utilized as a tool in resident education by assessing its accuracy on the PSITE.

Methods

Questions were obtained from the 2022 PSITE, which was present on the American Council of Academic Plastic Surgeons (ACAPS) website. Questions containing images or tables were carefully inspected and flagged before being inputted into ChatGPT. All responses by ChatGPT were qualified utilizing the properties of natural coherence. Responses that were found to be incorrect were divided into the following categories: logical, informational, or explicit fallacy.

Results

ChatGPT answered a total of 242 questions with an accuracy of 54.96%. The software incorporated logical reasoning in 88.8% of questions, internal information in 95.5% of questions, and external information in 92.1% of questions. When stratified by correct and incorrect responses, we determined that there was a statistically significant difference in ChatGPT's use of external information (P < .05).

Conclusions

ChatGPT is a versatile tool that has the potential to impact resident education by providing general knowledge, clarifying information, providing case-based learning, and promoting evidence-based medicine. With advancements in LLM and artificial intelligence (AI), it is possible that ChatGPT may be an impactful tool for resident education within Plastic Surgery.
VirPipe: an easy-to-use and customizable pipeline for detecting viral genomes from Nanopore sequencing
Authors: Kim Kijin , Park Kyungmin , Lee Seonghyeon , Baek Seung-Hwan , Lim Tae-Hun , Kim Jongwoo , Manavalan Balachandran , Song Jin-Won , Kim Won-Keun
Published: May 2023

Detection and analysis of viral genomes with Nanopore sequencing has shown great promise in the surveillance of pathogen outbreaks. However, the number of virus detection pipelines supporting Nanopore sequencing is very limited. Here, we present VirPipe, a new pipeline for the detection of viral genomes from Nanopore or Illumina sequencing input featuring streamlined installation and customization.

Availability and implementation

VirPipe source code and documentation are freely available for download at https://github.com/KijinKims/VirPipe, implemented in Python and Nextflow.
Sex-dependent effects of acute stress on amyloid-β in male and female mice
Authors: Edwards Hannah M , Wallace Clare E , Gardiner Woodrow D , Doherty Brookelyn M , Harrigan Ryan T , Yuede Kayla M , Yuede Carla M , Cirrito John R
Published: May 2023

The risk of developing Alzheimer’s disease is mediated by a combination of genetics and environmental factors, such as stress, sleep abnormalities and traumatic brain injury. Women are at a higher risk of developing Alzheimer’s disease than men, even when controlling for differences in lifespan. Women are also more likely to report high levels of stress than men. Sex differences in response to stress may play a role in the increased risk of Alzheimer’s disease in women.

In this study, we use in vivo microdialysis to measure levels of Aβ in response to acute stress in male and female mice. We show that Aβ levels are altered differently between female and male mice (APP/PS1 and wild-type) in response to stress, with females showing significantly increased levels of Aβ while most males do not show a significant change. This response is mediated through β-arrestin involvement in Corticotrophin Releasing Factor receptor signalling pathway differences in male and female mice as male mice lacking β-arrestin show increase in Aβ in response to stress similar to females.
Synergetic process between wind power and sewage sludge pyrolysis in a novel renewable-energy microgrid system
Authors: Liu Chang , Zhuo Jiankun , He Yanfeng , Li Shuiqing , Yao Qiang
Published: May 2023

To relieve the stress of sewage sludge (SS) disposal and effectively increase the use of renewable energy, a novel renewable-energy microgrid system (REMS) was developed, specifically designed to integrate a wind power plant (WPP) with energy storage and the SS pyrolysis process for heat and power generation. Based on a lab-scale pyrolysis experiment and 7-day numerical analysis, we studied the energy-recycling potential of SS and simulated the operational behaviours of REMS. According to the results, the calorific values of the pyrolytic gaseous and liquid products were better than those of the raw material, at 16.19 and 33.53 MJ/kg, respectively. The proposed REMS performed well in power supply and energy utilization with a design performance index of 99.23 when the WPP capacity was 200 MWe and the initial wind-energy curtailment rate was 30%. It indicates that by converting SS into flammable gas, condensable liquid and carbon-rich solid residue, curtailed wind energy could be saved and the synergy between wind power and the SS pyrolysis process enabled the proposed microgrid system to effectively utilize renewable energy and provide reliable on-demand power service. The REMS installed with a 155-MWe WPP achieved the optimal design in system performance, environmental benefit and construction cost under the initial wind-curtailment rate of 34.12%. The design scheme makes REMS capable of satisfying the 15.10-GWh power demand of end users and the 1700-t/day SS disposal need, and the curtailed wind energy could be reduced to zero.
Do temperature changes cause eczema flares? An English cohort study
Authors: Chan Jonathan , MacNeill Stephanie J , Stuart Beth , Lo Y T Eunice , Roberts Amanda  , Mitchell Dann , Ridd Matthew J
Published: May 2023

Background

It is unclear if ambient temperature changes affect eczema. It is also unclear if people with worse disease are more susceptible to weather-related flares, or specific types of emollient offer protection.

Objectives

To investigate the effect of short-term temperature variations on eczema symptoms in children.

Methods

Data from a UK cohort of 519 children with eczema were combined with data from the Hadley Centre’s Integrated Surface Database. Hot and cold weeks were defined by average regional temperature > 75th or < 25th percentile, January 2018 to February 2020. Eczema flares were defined as ≥ 3-point change in Patient-Oriented Eczema Measure (POEM). Random-effects logistic regression models were used to estimate the odds ratios of flares in hot and cold weeks (reference group: temperate weeks).

Results

The baseline mean age was 4.9 years (SD 3.2) and the POEM score was 9.2 (SD 5.5). From the 519 participants, there were 6796 consecutively paired POEMs and 1082 flares. Seasonal variation in POEM scores was observed, suggesting symptoms worsening in winter and improving in summer. Odds ratios of flares were: 1.15 [95% confidence interval (CI) 0.96–1.39, P = 0.14] in cold weeks and 0.85 (95% CI 0.72–1.00, P = 0.05) in hot weeks. The likelihood ratio test showed no evidence of this differing by disease severity (P = 0.53) or emollient type used (P = 0.55).

Conclusions

Our findings are consistent with previous studies demonstrating either improvements in eczema symptoms or reduced flares in hot weather. Worse disease and different emollient types did not increase susceptibility or provide protection against temperature changes. Further work should investigate the role of sunlight, humidity, pollution and other environmental factors.
Capability of Children with Hearing Devices: A Mixed Methods Study
Authors: Rijke Wouter J , Vermeulen Anneke M , Willeboer Christina , Knoors Harry E T , Langereis Margreet C , van der Wilt Gert Jan
Published: May 2023

We investigated 34 deaf and hard-of-hearing children with hearing devices aged 8–12 years and 30 typical hearing peers. We used the capability approach to assess well-being in both groups through interviews. Capability is “the real freedom people have to do and to be what they have reason to value.” Speech perception, phonology, and receptive vocabulary data of the deaf and hard-of-hearing children, that were used retrospectively, showed a large variability. The analysis of the relation between clinical quantitative outcome measures and qualitative capability interview outcomes suggests that at this age, differences in clinical performance do not appear to translate into considerable differences in capability, including capability did offer insight into the factors that appeared to ensure this equivalence of capability. We argue that capability outcomes should be used to determine the focus of (auditory) rehabilitation and support, in line with the United Nations Convention on the Rights of the Child.
Ostial stenosis of reimplanted left main coronary artery and supravalvular pulmonary stenosis: a case report of two complications of surgery for anomalous left coronary artery from the pulmonary artery
Authors: Alghamdi Fatima Abdullah , Shah Muhammad Azam , Alshalash Saleh , Alkhodair Abdullah Mohammed
Published: May 2023

Background

Anomalous origin of the coronary artery from the pulmonary artery (ALCAPA) is a rare congenital disease. Surgical re-implantation of the left main coronary artery (LMCA) to the aorta is a definitive treatment with a good prognosis.

Case summary

A 9-year-old boy was admitted with a complaint of exertional chest pain and dyspnoea. At 13 months of age, he was diagnosed to have ALCAPA as a workup of severe left ventricular systolic dysfunction and underwent coronary re-implantation of ALCAPA. Coronary angiogram displayed the high takeoff of re-implanted LMCA with significant ostial stenosis, and echocardiogram showed significant supravalvular pulmonary stenosis (SVPS) with a peak gradient of 74 mmHg. After a multidisciplinary team discussion, he underwent percutaneous coronary intervention with stenting to ostial LMCA. On follow-up, he was asymptomatic and a cardiac computed tomography scan showed a patent stent in LMCA with an under-expanded area in the mid-segment. The proximal part of the LMCA stent was located very close to the stenotic segment of the main pulmonary artery making it a high risk for balloon angioplasty. The surgical intervention of SVPS is delayed to allow the somatic growth of the patient.

Discussion

Percutaneous coronary intervention in re-implanted LMCA is a feasible option. If stenosis of re-implanted LMCA is accompanied by SVPS, the latter can be best treated surgically and staged to decrease the operative risk. Our case also demonstrates the importance of long-term follow-up of post-operative complications of patients with ALCAPA.
Police Response Time and Injury Outcomes
Authors: DeAngelo Gregory , Toger Marina , Weisburd Sarit
Published: May 2023

The delayed response of law enforcement to calls for service has become a hot button issue when evaluating police department performance. While it is often assumed that faster response times could play an important role in quelling potentially violent incidents, there is no empirical evidence to support this claim. In this paper, we measure the effect of police response time on the likelihood that an incident will result in an injury. To overcome the endogeneity of more severe calls being assigned higher priority, which requires a faster response, we take several steps. First, we focus on the subset of calls for service categorised as ‘Major Disturbance—Violence’ that all receive the same priority level. Second, we instrument for police response time with the number of vehicles within a 2.5-mile radius of the incident at the time it is received by the call centre. When controlling for beat, month and time-of-day fixed effects, this instrumenting strategy allows us to take advantage of the geographical constraints faced by a dispatcher when assigning officers to an incident. In contrast to the ordinary least squares estimates, our two-stage least squares analysis establishes a strong causal relationship whereby increasing response time increases the likelihood that an incident results in an injury. The effect is concentrated among female victims, suggesting that faster response time could potentially play an important role in reducing injuries related to domestic violence.