bluuebunny/crossref_metadata_2025 huggingface dataset:
Energy performance and flow characteristics of a slanted axial-flow pump under cavitation conditions
Authors: Fei Zhaodan , Zhang Rui , Xu Hui , Feng Jiangang , Mu Tong , Chen Yaohui
Published: March 2022

Cavitation is a complex flow phenomenon that hinders the efficient, safe, and stable operation of hydraulic machinery. To investigate the effect of cavitation on energy performance and flow characteristics of hydraulic machinery, cavitating flow in a slanted axial-flow pump based on entropy production theory and vortex dynamics is studied. The results show that the impeller chamber is a primary region of cavitation and energy loss generation under different cavitation conditions, including the incipient, growing, and wedge-shaped cavitation stages. In the incipient cavitation stage, as degree of cavitation strengthens, the flow at the impeller blade is smooth with little cavitation, and the variation in entropy production is constant, resulting in a stable energy performance. As it evolves into the wedge-shaped stage, the cavitation grows from the tip region near the impeller blade to the hub. At this time, the entropy production increases in the impeller chamber, resulting in a drop in energy performance. Meanwhile, flow separation appears at the impeller blade, and a secondary tip leakage vortex is promoted. The region with high vorticity basically matches the region with the high local entropy production rate. According to the relative vorticity transport equation, compressibility of cavitation strongly affects the relative vorticity in the impeller chamber, indicating that cavitation indirectly increases entropy production and energy loss by affecting the vorticity distribution, resulting in the drop in energy performance.
An investigation into the scaling law of converging length for compressible round twin-jet
Authors: Perumal Arun Kumar
Published: March 2022

An experimental investigation has been conducted to develop the scaling law for the converging length of compressible round twin-jets. A twin-jet system with nozzle exit diameter D and normalized inter-nozzle spacing S/D of 3, 4, and 5 was investigated at ideally expanded jet Mach numbers Mj of 0.3, 0.5, 0.7, 1.0, 1.35, and 1.56. Scaling analysis performed for the converging length xcp revealed that the relationship xcp/D=g1(Mj,S/D) could be reduced to xcp/(S1.8/D0.8)=g2(Mj), where g1 and g2 are different functions. This scaling law extended to include both perfectly and imperfectly expanded sonic and supersonic twin-jets, leading to the relation xcp/(S1.8/D0.8), is proportional to (γMj2pepa)1/(jc+1), where pe/pa, γ, and jc are the nozzle expansion ratio, gas specific heat ratio, and index number, respectively. It has been documented that S1.8/D0.8 is the length scale to normalize xcp, which is valid for subsonic, sonic, and supersonic twin-jets. As such, for a given pe/pa and Mj, the dependence of xcp/D on S/D can be predicted using the scaling law xcp/(S1.8/D0.8). Further, the scaling law is discussed, leading to an interpretation of the physical meaning of the dimensionless parameter (γMj2pepa)1/(jc+1).
Corrigendum to: Model for integrated care for chronic disease in the Australian context: Western Sydney Integrated Care Program
Authors: Cheung N. Wah , Crampton Michael , Nesire Victoria , Hng Tien-Ming , Chow Clara K. ,   on behalf of the Western Sydney Integrated Care Program Investigators
Published: March 2022

ObjectiveTo describe the implementation of a model of integrated care for chronic disease in Western Sydney. This model was established on the basis of a partnership between the Local Health District and the Primary Health Network. MethodsThe Western Sydney Integrated Care Program (WSICP) focuses on people with type 2 diabetes, chronic obstructive pulmonary disease and coronary artery disease or congestive cardiac failure. We describe the design of the program, the processes involved and some of the challenges and barriers to integration. ResultsEarly data indicate a high uptake of services, with some evidence of a reduction in hospital admissions and presentations to the emergency department. ConclusionA model of integrated care has been successfully implemented and embedded into local practices. Preliminary data suggest that this is having an impact on the utilisation of hospital services. What is known about the topic?There is evidence that integrated models can improve cost-effectiveness and the quality of clinical care for people with chronic disease. However, most integrated models are small scale, focus on very specific populations and generally do not engage both primary care and acute hospitals. What does this paper add?This paper describes an effective partnership between state-funded hospital services in the WSLHD and the federally funded local Primary Health Network (PHN) of general practitioners. The paper outlines the design of the program and the structural, governance and clinical steps taken to embed integrated care into everyday clinical practice. In addition, preliminary results indicate a reduction in the use of hospital services by people who have received integrated care services. What are the implications for practitioners?Involvement of both primary care and the public hospital system is important for a successful and sustainable integrated care program. This is a long and challenging process, but it can lead to positive effects not just for individuals, but also for the health system as a whole.
Corrigendum to: Cancer patients’ use of and attitudes towards medicinal cannabis
Authors: Drosdowsky Allison , Blaschke Sarah , Koproski Trista , Fullerton Sonia , Thakerar Arti , Ellen Steve , Phipps-Nelson Jo , de Neef Corry
Published: March 2022

ObjectivesAccess to medicinal cannabis is a timely and important issue in cancer care. Recent legislative changes in Australia have increased access to medicinal cannabis, but the views of people with cancer on this topic are poorly understood. The aim of this study was to explore the prevalence of the use of and attitudes towards medicinal cannabis among people with cancer. MethodsA cross-sectional study was performed using an anonymous, 15-item study-specific paper-based survey. The survey was administered over a 2-week period in August 2017 in the waiting rooms of a specialist cancer hospital. ResultsIn all, 339 patients completed the survey (mean (±s.d.) age 59±15 years; 52% male). Fourteen respondents (4%) were currently using cannabis medicinally. Only one of these respondents had a prescription for their cannabis product. Most respondents would consider using a medicinal cannabis product if recommended by their doctor (n=271; 80%). ConclusionThis study is the first of its kind to survey the use of and attitudes towards medicinal cannabis in a broad sample of Australian people with cancer. Few respondents were currently using cannabis for medicinal purposes, but an overwhelming majority were in favour of increasing access and would consider using a prescribed product. What is known about the topic?Cannabis may have a wide variety of medicinal uses, particularly in the cancer setting. Currently, people with cancer in Victoria have limited access to medicinal cannabis despite recent legislative changes. What does this paper add?In a general sample of people with cancer, few were using cannabis for medicinal purposes, but most were in favour of widening access and would consider using a product their doctor prescribed. What are the implications for practitioners?Despite supporting access, patients indicated that the recommendations of doctors and increasing the evidence base are necessary requirements to their use of medicinal cannabis.
A review of environmental contamination and potential health impacts on aquatic life from the active chemicals in sunscreen formulations
Authors: Wheate Nial J.
Published: March 2022

The active chemicals in sunscreen formulations are released into the environment from human skin, and found in recreational-use waters like seawater, but can also be washed into fresh water from bathing and showering. The level of sunscreen chemicals found in samples varies considerably between regions, time of year (higher in summer months), and time of day. Average typical concentrations are only in the nanograms per litre (ng L−1) range in marine and fresh water systems, and typically, the highest levels are in waste-water sludge because of a concentrating effect during the treatment process. From numerous studies, it is known that the active chemicals in sunscreens can have potential hormonal/oestrogenic activity and non-hormonal effects, including: acting as teratogens, altering gene regulation, inducing changes in antioxidant and free radical production, and inducing coral bleaching. However, the effects of sunscreens on aquatic life under laboratory conditions typically occur only at concentrations (µg or mg L−1) that far exceed (10–10 000-fold) levels found in the environment. As such, when damage does occur to reefs and animal life, there are often other causes that are more likely impacting the aquatic life including changes in water temperature, water turbidity, elevated nutrient levels, and the presence of pesticides and medicines used for human and animal health.
Ameliorative effect of Halopteris filicina extracts on growth parameters and genomic DNA template stability of tomato (Solanum lycopersicum) under lead chloride stress
Authors: Unal Dilek , Sevim Gulcin , Varis Gokay , Tuney-Kizilkaya Inci , Turkyilmaz Unal Bengu , Ozturk Munir
Published: March 2022

Lead is a toxic element that accumulates in agricultural soils through various anthropogenic sources. It inhibits the growth and development of plants and causes mutations in DNA. Macroalgae such as Halopteris filicina contain multifunctional components that may improve plant tolerance to lead stress. In this study, seeds of tomato (Solanum lycopersicum) were subjected to six treatments comprising two levels of lead exposure (60 or 120 μM PbCl2) with or without H. filicina extract (0.5% in distilled water), a distilled water control, and a positive control (H. filicina extract) for 7 days. Physiological responses were investigated. Seedlings that had been treated with 60 and 120 μM PbCl2 without H. filicina extract showed root growth reduction of 55% and 68.6%, respectively, relative to the control, whereas for 60 and 120 μM PbCl2-treated seedlings with H. filicina extract applied, the reductions in root growth were lower, at 27.44% and 50.51%. The seedling viability index was decreased by 68.14% at 120 μM PbCl2 application without H. filicina extract, whereas a 42.48% reduction was recorded for 120 μM PbCl2-treated seedlings with H. filicina extract applied. Moreover, PbCl2 accumulation resulted in a decrease in leaf pigment content. Leaf pigment content was high in plants receiving the H. filicina extract. The rate of lipid peroxidation caused by PbCl2 was reduced with application of H. filicina extract. Genomic template stability was determined by using the inter simple sequence repeat-PCR technique, which revealed a decrease in DNA stabilisation with an increase in lead accumulation. However, this was alleviated by application of H. filicina extract. Our findings indicate that H. filicina extract both stimulates plant growth and protects from toxic effects by reducing accumulation of metals in the cell.
Self-reported anal symptoms and their association with anal pathology among gay and bisexual men: a cross-sectional observational analysis
Authors: Goddard Sian L. , Poynten I. Mary , Petoumenos Kathy , Jin Fengyi , Hillman Richard J. , Law Carmella , Roberts Jennifer M. , Fairley Christopher K. , Garland Suzanne M. , Grulich Andrew E. , Templeton David J. ,   on behalf of the Study of the Prevention of Anal Cancer (SPANC) Research Team
Published: March 2022

Background Anal symptoms may indicate serious pathology. Receptive anal intercourse (RAI) and sexually transmissible infections (STIs) may contribute to a higher prevalence of symptoms among gay and bisexual men (GBM). This study investigated associations with anal symptoms among GBM. Methods: The Study of the Prevention of Anal Cancer was a longitudinal study of anal human papillomavirus and related lesions in Sydney, Australia. GBM aged ≥35 years were recruited from community settings between September 2010 and August 2015. Information about anal symptoms (discharge, itch, pain defecating, lump, bleeding, ‘sores’, tearing, tenesmus), STIs and sexual behaviours was collected. High-resolution anoscopy (HRA) and STI testing were performed. Logistic regression analyses on baseline data were performed to assess associations with each symptom. Results: Among 616 participants (median age 49 years, 35.9% HIV positive), 35.3% reported at least one anal symptom within the past week and 65.3% were diagnosed with fistula, fissure, ulcer, warts, haemorrhoids and/or perianal dermatoses at HRA. Anal symptoms were not associated with anal chlamydia, gonorrhoea, warts or syphilis. Self-reported ‘sores’ were associated with previous anal herpes simplex virus (HSV; P < 0.001). ‘Sores’ (P < 0.001), itch (P = 0.019), discharge (P = 0.032) and lump (P = 0.028) were independently associated with ulceration. Among participants diagnosed with fissure, fistulae, haemorrhoids and perianal dermatoses, 61.9%, 100%, 62.0% and 63.9% respectively were asymptomatic. Only self-reported anal tear was independently associated with recent RAI. Conclusions: Previous anal HSV was the only STI associated with any symptom. Anal pathology was highly prevalent, but often asymptomatic. Anal symptoms do not appear to be useful markers of most anal pathology in GBM.
Peripheral Aβ acts as a negative modulator of insulin secretion
Authors: Shigemori Keiko , Nomura Sachiko , Umeda Tomohiro , Takeda Shuko , Tomiyama Takami
Published: March 2022

Significance

The cerebral accumulation of amyloid β (Aβ) is a hallmark of Alzheimer’s disease (AD). While type 2 diabetes mellitus is known to be a risk factor for AD, the underlying mechanisms remain unclear. In the present study, we demonstrate that plasma Aβ is produced from glucose- and insulin-susceptible peripheral tissues, such as the pancreas, adipose tissues, skeletal muscles, and liver, to inhibit insulin secretion from islet β-cells. Our findings suggest a physiological role of peripheral Aβ in glucose and insulin metabolism and a possible mechanism linking diabetes to AD. In addition, although plasma Aβ levels are currently used as a diagnostic biomarker of AD, our data suggest they should be used with caution.
High Energy Inner Shell Photoelectron Diffraction in CO2
Authors: Li Xiaohong , Ding Bocheng , Feng Yunfei , Wu Ruichang , Tian Lifang , Huang Jianye , Liu Xiaojing
Published: March 2022

Photoelectron diffraction is an effective tool to probe the structures of molecules. The higher the photoelectron kinetic energy is, the higher order the diffraction pattern is disclosed in. Up to date, either the multi-atomic molecule with the photoelectron kinetic energy below 150 eV or the diatomic molecule with 735 eV photoelectron has been experimentally reported. In this study, we measured the diffraction pattern of C 1s and O 1s photoelectrons in CO2 with 319.7 and 433.5 eV kinetic energies, respectively. The extracted C–O bond lengths are longer than the C–O bond length at the ground state, which is attributed to the asymmetric fragmentation that preferentially occurs at the longer chemical bond side during the zero-energy asymmetric vibration.
Vector Spatiotemporal Solitons and Their Memory Features in Cold Rydberg Gases
Authors: Zhao Yuan , Lei Yun-Bin , Xu Yu-Xi , Xu Si-Liu , Triki Houria , Biswas Anjan , Zhou Qin
Published: March 2022

We propose a scheme to generate stable vector spatiotemporal solitons through a Rydberg electromagnetically induced transparency (Rydberg-EIT) system. Three-dimensional vector monopole and vortex solitons have been found under three nonlocal degrees. The numerical calculation and analytical solutions indicate that these solitons are generated with low energy and can stably propagate along the axes. The behavior of vector spatiotemporal solitons can be manipulated by the local and nonlocal nonlinearities. The results show a memory feature as these solitons can be stored and retrieved effectively by tuning the control field.
Structure and Wettability Engineering of Polycrystalline Diamond Films Treated by Thermally Oxidation, Second Growth and Surface Termination
Authors: Wan Linfeng , Mu Caoyuan , Liu Yaofeng , Cheng Shaoheng , Wang Qiliang , Li Liuan , Li Hongdong , Zou Guangtian
Published: March 2022

High-quality polycrystalline diamond films with dominated (100)-oriented grains are realized by combining the thermally oxidation and the homogeneous second growth processes. Moreover, we investigate the wettability property of the polycrystalline diamonds in various stages. Different surface structures (with various grain sizes, voids, and orientations, etc.) and terminations (hydrogen or oxygen) have significant effects on the wettability of polycrystalline diamond films. The wettability is further closely related to the polarity of solutions. By measuring the contact angle and calculating the dispersion and polarity components, we estimate the surface energy of polycrystalline diamond films, and explore the factors affecting the surface energy. The modulations in growth quality and wettability property of polycrystalline diamond films provide valuable data for development of diamond-based multiple devices in practical applications.
Dynamic Cantilever Magnetometry of Paramagnetism with Slow Relaxation
Authors: Ma Zhiyu , Fan Kun , Li Qi , Xu Feng , Zou Lvkuan , Wang Ning , Zheng Li-Min , Xue Fei
Published: March 2022

Dynamic cantilever magnetometry is a sensitive method that has been widely used in studying magnetic anisotropy in ferromagnetic materials and Fermi surface in quantum materials. We study a cobalt-iridium metal-metalloligand coordination polymer using dynamic cantilever magnetometry. The experimental data of dynamic cantilever magnetometry are well explained using the proposed model for Langevin paramagnetism with slow relaxation. Based on the proposed model, we calculate the magnetization and magnetic susceptibility of paramagnetic materials from frequency shifts of a cantilever. The extracted magnetization and magnetic susceptibility are consistent with those obtained from conventional DC and AC magnetometry. The proposed slow relaxation picture is probably a general model for explaining dynamic cantilever magnetometry data of paramagnetic materials, including previously observed dynamic cantilever magnetometry data of paramagnetic metals [Gysin et al. 2011 Nanotechnology
22 285715].
Nanoscale Impact Ionization and Electroluminescence in a Biased Scanning-Tunneling-Microscope Junction
Authors: Gu Lehua , Wu Shuang , Zhang Shuai , Wu Shiwei
Published: March 2022

Electroluminescence from a p-type GaAs(110) surface was induced by tunneling electrons in a scanning tunneling microscope under both polarities of bias voltage. The optical spectra exhibit a polarity-independent luminescence peak at 1.47 eV resulting from the exciton recombination. However, the quantum yield of photon emission at negative bias voltage is two orders of magnitude weaker than that at positive bias voltage. Moreover, the luminescence at negative bias voltage shows the linear dependence of bias voltage, distinct from the rapid rise due to resonant electron injection at positive bias. Furthermore, the threshold bias voltage for electroluminescence at negative bias is nearly twice the bandgap of GaAs, not simply satisfying the energy conservation for the creation of an electron-hole pair. Through theoretical calculation, we propose an impact ionization model to nicely explain the newly observed electroluminescence at negative bias voltage. We believe that this mechanism of impact ionization could be readily applied to other nanoscale optoelectronics including 2D semiconductors and 1D nanostructures.
Sub-optical-cycle electron pulse trains from metal nanotips
Authors: Eldar Maor , Abo-Toame Salma , Krüger Michael
Published: March 2022

The coherent modulation of swift electron beams with strong laser fields has enabled the generation of attosecond electron pulses, opening up new research avenues in ultrafast science. Here we study a comparatively simple alternative, the production of electron pulse trains directly at the source. In our theory work, we show that sub-optical-cycle electron bursts induced by tunneling photoemission from a metal nanotip can retain the temporal fingerprint of their emission dynamics in a typical low-energy point-projection microscope setup. We find that strong acceleration by a static field, a short propagation distance and a sufficiently large optical cycle duration mitigate temporal smearing due to matter-wave dispersion. Our approach enables studies of coherent interactions of slow electrons with matter on sub-femtosecond and nanometer scales, a regime which has hitherto remained inaccessible.
Mini band gap generation in magnetic beta-borophene: effects of optical phonon interaction
Authors: Akay Defne , Maiti Santanu K
Published: March 2022

In this work we report for the first time, to the best of our knowledge, the tunable electronic properties of beta-borophene (BB) on the polar substrate (

Zr

O

2

). We provide an analytical prescription for the calculation of ground state energy in the presence of the electron–phonon (e-ph) interaction, within the framework of the Lee-Low-Pines theory. In the theoretical investigation of the polaron formation in BB, we describe its effective masses, polaronic band-gap, mobility, and Fermi velocities, which are different in each coordinate due to the out-of-plane buckling structure. We also analyze how the average effective mass and Fermi velocities of the charge carriers in the buckling structure are affected by the external magnetic field. It is shown that the polaronic energy becomes more effective in presence of a magnetic field, which we confirm through an analytical prescription. The characteristics of the evolution of average effective mass and average effective Fermi velocity in the presence of a magnetic field are critically discussed. We find that the average effective Fermi velocity is less sensitive, while the mass is greatly influenced by the magnetic field.
Coalescence, the thermal model and multi-fragmentation: the energy and volume dependence of light nuclei production in heavy ion collisions
Authors: Hillmann Paula , Käfer Katharina , Steinheimer Jan , Vovchenko Volodymyr , Bleicher Marcus
Published: March 2022

We present results of a phase space coalescence approach within the UrQMD transport and -hybrid model for a very wide range of beam energies from SIS to LHC. The coalescence model is able to qualitatively describe the whole range of experimental data with a fixed set of parameters. Some systematic deviations are observed for very low beam energies where the role of feed down from heavier nuclei and multi-fragmentation becomes relevant. The coalescence results are mostly very close to the thermal model fits. However, both the coalescence approach as well as thermal fits are struggling to simultaneously describe the triton multiplicities measured with the STAR and ALICE experiment. The double ratio of tp/d
2, in the coalescence approach, is found to be essentially energy and centrality independent for collisions of heavy nuclei at beam energies of E
lab > 10A GeV. On the other hand the clear scaling of the d/p
2 and t/p
3 ratios with the systems volume is broken for peripheral collisions, where a canonical treatment and finite size effects become more important.
Research on the deformed halo in 29F with a complex momentum representation method
Authors: Zhai Shu-Yuan , Cao Xue-Neng , Guo Jian-You
Published: March 2022

The weakly bound nucleus 29F locates near the neutron drip line. Experiments have confirmed that it is the heaviest two-neutron halo nucleus discovered up to now. To understand the halo structure in 29F, we explore the weakly bound and resonant levels close to the Fermi surface with the complex momentum representation method. Not only the narrow resonances and the broad resonances. Since the broad resonance 2p
3/2 is disclosed, the p − f inversion and N = 20 shell gap quenching are found. The last valence neutron can occupy the weakly bound level 1/2[310], composed mainly of p
3/2–component, or the 1/2[211], composed mainly of s
1/2–component. Since the wavefunctions of p and s–components extend to a large range in the coordinate space, which results in the density distributions of the levels 1/2[310] and 1/2[211] being considerably diffuse. This is the most likely cause of halo formation in 29F and the halo may be formed by the p–component, s–component, or their mixtures by pairing correlations.
Comparison of heavy ion transport simulations: Ag + Ag collisions at E
lab = 1.58A GeV
Authors: Reichert Tom , Elz Alexander , Song Taesoo , Coci Gabriele , Winn Michael , Bratkovskaya Elena , Aichelin Jörg , Steinheimer Jan , Bleicher Marcus
Published: March 2022

We compare the microscopic transport models UrQMD, PHSD, PHQMD, and SMASH to make predictions for the upcoming Ag + Ag data at E
lab = 1.58A GeV (

s

NN

=
2.55

GeV) by the HADES collaboration. We study multiplicities, spectra and effective source temperatures of protons, π
±,0, K
±, the η, Λ + Σ0 and the Ξ− within these models. Despite variations in the detailed implementation of the dynamics in the different models, the employed transport approaches all show consistent multiplicities of the bulk of investigated hadrons. The main differences are in the Ξ− production, which is treated differently between UrQMD/SMASH on one side employing high mass resonance states with explicit decays to Resonance → Ξ + K + K in contrast to PHSD/PHQMD which account only non-resonant Ξ production channels. A comparison of the spectra, summarized by effective source temperatures, shows that all models provide similar source temperatures around T
source = 80–95 MeV, and show substantial radial flow on the order of ⟨v

T
⟩ = 0.18c − 0.24c even for such a small system.
The effect of metal–insulator interface interactions on electrical transport in granular metals
Authors: Gilbert Simeon J , Rosenberg Samantha G , Kotula Paul G , Kmieciak Thomas G , Biedermann Laura B , Siegal Michael P
Published: March 2022

We present an in-depth study of metal–insulator interfaces within granular metal (GM) films and correlate their interfacial interactions with structural and electrical transport properties. Nominally 100 nm thick GM films of Co and Mo dispersed within yttria-stabilized zirconia (YSZ), with volumetric metal fractions (φ) from 0.2–0.8, were grown by radio frequency co-sputtering from individual metal and YSZ targets. Scanning transmission electron microscopy and DC transport measurements find that the resulting metal islands are well-defined with 1.7–2.6 nm average diameters and percolation thresholds between φ = 0.4–0.5. The room temperature conductivities for the φ = 0.2 samples are several orders of magnitude larger than previously-reported for GMs. X-ray photoemission spectroscopy indicates both oxygen vacancy formation within the YSZ and band-bending at metal–insulator interfaces. The higher-than-predicted conductivity is largely attributed to these interface interactions. In agreement with recent theory, interactions that reduce the change in conductivity across the metal–insulator interface are seen to prevent sharp conductivity drops when the metal concentration decreases below the percolation threshold. These interface interactions help interpret the broad range of conductivities reported throughout the literature and can be used to tune the conductivities of future GMs.
Thickness dependent band structure of α-bismuthene grown on epitaxial graphene
Authors: Takahashi Kazutoshi , Imamura Masaki , Yamamoto Isamu , Azuma Junpei
Published: March 2022

Along with the great interest in two-dimensional elemental materials that has emerged in recent years, atomically thin layers of bismuth have attracted attention due to physical properties on account of a strong spin–orbit coupling. Thickness dependent electronic band structure must be explored over the whole Brillouin zone in order to further explore their topological electronic properties. The anisotropic band structures along zig-zag and armchair directions of α-bismuthene (α-Bi) were resolved using the two-dimensional mapping of angle-resolved photoemission spectra. An increase in the number of layers from 1- to 2-bilayers (BLs) shifts the top of a hole band on

Γ

¯

–

X

¯

1

line to high wavenumber regions. Subsequently, an electron pocket on

Γ

¯

–

X

¯

1

line and a hole pocket centred at

Γ

¯

point appears in the 3 BL α-Bi. Gapless Dirac-cone features with a large anisotropy were clearly resolved on

X

¯

2

point in the 1-BL and 2-BL α-Bi, which can be attributed to the strong spin–orbit coupling and protection by the nonsymmorphic symmetry of the α-Bi lattice.
An underwater moving dipole tracking method of artificial lateral line based on intelligent optimization and recursive filter
Authors: Liu Yu , Hu Qiao , Yang Qian , Li Yixin , Fu Tongqiang
Published: March 2022

Inspired by the lateral line system of fish, an artificial lateral line system is proposed for underwater target detection. The dipole is treated as a standard and simplified target. In previous studies, most researchers focused on the dipole at a fixed position and the trajectory tracking of a moving dipole was barely considered. In this paper, a new trajectory tracking method for a moving dipole is proposed. First, based on the instant pressure amplitude and loss function, the dipole trajectory is tracked by particle swarm optimization (PSO). Then, the PSO-tracked trajectory is optimized by using recursive filters such as a Kalman filter (KF) and a particle filter (PF) to reduce the tracking error. The experiment result showed that when the trajectory of the dipole was rectangular, the target tracking accuracy of PSO was competitive compared with the Gauss–Newton method. The mean error distance (MED) of PSO was 12.51 mm. The PF showed better optimization performance than the KF in this study, and the corresponding MED of the PF was 7.064 mm. The main factor that caused tracking errors was pressure mismatch. In the simulation, when pressure mismatch was not considered, the performance of the proposed dipole tracking method was highly improved.
A neural network with nuisance attribute projection: a novel method for bearing fault diagnosis under variable speed
Authors: Ma Huijie , Li Shunming , Lu Jiantao , Gong Siqi , Yu Tianyi
Published: March 2022

Rolling bearings are a widely used component in rotating machinery, and deterioration of their performance may lead to machine breakdown and accidents. However, because rolling bearings often work under time-varying working conditions it is a great challenge to accurately separate fault features from working condition features. This paper presents a new neural network framework for variable speed fault diagnosis. The proposed neural network can eliminate the influence of condition information during training. Firstly, samples of the same category under different working conditions are distinguished. Secondly, a projection matrix is designed at the last layer of the neural network to project the features extracted through forward propagation to a hyperplane of the same latitude, so that the fault features are more obvious. Finally, a network model that can distinguish fault features from working conditions is obtained through back propagation training. In addition, we propose a multi-loss function, which can reduce the within-class distance and enlarge the between-class distance. The method is validated using bearing datasets under time-varying rotation speeds. The results show that our method has higher accuracy with a simple structure, and is a great improvement on the traditional method of bearing fault diagnosis.
Statistics of internal stress fluctuations in dislocated crystals and relevance to density-based dislocation dynamics models
Authors: Vivekanandan Vignesh , Anderson Joseph Pierre , Pachaury Yash , Mohamed Mamdouh S , El-Azab Anter
Published: March 2022

A statistical analysis of internal stress fluctuations, defined as the difference between the local mean stress and stress on dislocations, is presented for deforming crystals with 3D discrete dislocation systems. Dislocation realizations are generated using dislocation dynamics simulations and the associated stress field is computed as a superposition of a regularized stress field of dislocation lines within the domain of the solution and a complementary stress field computed via a finite-element boundary value problem. The internal stress fluctuations of interest are defined by an ensemble of the difference between the stress on dislocation lines and the local mean field stress in the crystal. The latter is established in a piecewise fashion over small voxels in the crystal thus allowing the difference between the local average stress and stress on segments to be easily estimated. The results show that the Schmid stress (resolved shear stress) and Escaig stress fluctuations on various slip systems sampled over a random set of points follow a Cauchy (Lorentz) distribution at all strain levels, with the amplitude and width of the distribution being dependent on the strain. The implications of the Schmid and Escaig internal stress fluctuations are discussed from the points of view of dislocation cross-slip and the dislocation motion in continuum dislocation dynamics.
Electrospun PAN-HNTs composite nanofiber membranes for efficient electrostatic capture of particulate matters
Authors: Hu Shiqian , Chen Ruowang , Lu Peng , Zheng Zida , Gu Gangwei , Wang Mingyuan , Zhang Xiaowei
Published: March 2022

The fine particulate matter (PM) pollution has become a serious concern to public health. As the core part of PM air filters, high-performance electrostatic nanofiber membranes are urgently needed. However, the existing air filters remain challenging to further decrease the pressure drop to improve the wearer comfort. On the other hand, the rapidly disappearing static electricity of the existing electrostatic nanofiber inevitably gives rise to a relatively short service life. Here, we demonstrate a novel and enhanced electrostatic nanofiber membrane by introducing the halloysite nanotubes (HNTs) to the traditional electrospun PAN nanofiber membrane. The optimal PAN-HNTs nanofiber membrane shows a high removal efficiency of 99.54%, a low pressure drop of 39 Pa, and a high quality factor of 0.89 Pa−1. This greatly improved filtration performance can be attributed to the increased surface area and diameter of nanofiber after introducing the HNTs as additives with suitable doping concentrations. More importantly, compared with the pure PAN nanofiber membrane, the electrostatic capacity of the PAN-HNTs nanofiber membrane is significantly enhanced, which is confirmed by the leaf electroscope. After introducing the HNTs as additives, the surface of the PAN-HNTs nanofiber membrane becomes hydrophilic, which benefits for preventing foulants from attaching to the surface. We anticipate that the PAN-HNTs nanofibers as high-performance membrane air filters will bring great benefits to public health.
Self-powered topological insulator Bi2Te3/Ge heterojunction photodetector driven by long-lived excitons transfer
Authors: Yin Qin , Si Guoxiang , Li Jiao , Wali Sartaj , Ren Junfeng , Guo Jiatian , Zhang Hongbin
Published: March 2022

Due to the wide spectral absorption and ultrafast electron dynamical response under optical excitation, topological insulator (TI) was proposed to have appealing application in next-generation photonic and optoelectronic devices. Whereas, the bandgap-free speciality of Dirac surface states usually leads to a quick relaxation of photoexcited carriers, making the transient excitons difficult to manipulate in isolated TIs. Growth of TI Bi2Te3/Ge heterostructures can promote the specific lifetime and quantity of long-lived excitons, offering the possibility of designing original near-infrared optoelectronic devices, however, the construction of TI Bi2Te3/Ge heterostructures has yet to be investigated. Herein, the high-quality Bi2Te3/Ge heterojunction with clear interface was prepared by physical vapor deposition strategy. A significant photoluminescence quenching behaviour was observed by experiments, which was attributed to the spontaneous excitation transfer of electrons at heterointerface via theoretical analysis. Then, a self-powered heterostructure photodetector was fabricated, which demonstrated a maximal detectivity of 1.3 × 1011 Jones, an optical responsivity of 0.97 A W−1, and ultrafast photoresponse speed (12.1 μs) under 1064 nm light illumination. This study offers a fundamental understanding of the spontaneous interfacial exciton transfer of TI-based heterostructures, and the as-fabricated photodetectors with excellent performance provided an important step to meet the increasing demand for novel optoelectronic applications in the future.
Validation of the smooth step model by particle-in-cell/Monte Carlo collisions simulations
Authors: Klich Maximilian , Löwer Jan , Wilczek Sebastian , Mussenbrock Thomas , Brinkmann Ralf Peter
Published: March 2022

Bounded plasmas are characterized by a rapid but smooth transition from quasi-neutrality in the volume to electron depletion close to the electrodes and chamber walls. The thin non-neutral region, the boundary sheath, comprises only a small fraction of the discharge domain but controls much of its macroscopic behavior. Insights into the properties of the sheath and its relation to the plasma are of high practical and theoretical interest. The recently proposed smooth step model (SSM) provides a closed analytical expression for the electric field in a planar, radio-frequency modulated sheath. It represents (i) the space charge field in the depletion zone, (ii) the generalized Ohmic and ambipolar field in the quasi-neutral zone, and (iii) a smooth interpolation for the transition in between. This investigation compares the SSM with the predictions of a more fundamental particle-in-cell/Monte Carlo collisions simulation and finds good quantitative agreement when the assumed length and time scale requirements are met. A second simulation case illustrates that the model remains applicable even when the assumptions are only marginally fulfilled.
Electrical transport properties of highly doped N-type GaN materials
Authors: Konczewicz L , Litwin-Staszewska E , Zajac M , Turski H , Bockowski M , Schiavon D , Chlipała M , Iwinska M , Nita P , Juillaguet S , Contreras S
Published: March 2022

This paper presents a comparative study of electron transport phenomena in n-type gallium nitride strongly doped, above the Mott transition, with silicon and germanium. The samples under study were grown by molecular beam epitaxy, metal-organic vapor phase epitaxy and halide vapor phase epitaxy. The temperature dependence of resistivity and Hall Effect was investigated at temperatures ranging from 10 K up to 650 K. The measurements at sub-room temperatures allow the study of scattering mechanisms related to extrinsic material properties. The observed temperature dependences of the electrical transport properties were analyzed in the frame of the model taking into account a typical scattering mechanism and degree of degeneracy of free carrier electron gas. The limitations of the applied models will be presented.
Tests of gluino-driven radiative breaking of the electroweak symmetry at the LHC
Authors: Aboubrahim Amin , Klasen Michael , Nath Pran , Syed Raza M
Published: March 2022

The recent muon g − 2 result from Fermilab combined with the Brookhaven result, strongly points to new physics beyond the Standard Model which can be well described by the electroweak sector of supersymmetry if the masses of the sleptons and some of the electroweak gauginos are in the few hundred GeV range. However, the Higgs boson mass measurement at 125 GeV indicates a mass scale for squarks which lies in the few TeV region indicating a split mass spectrum between squarks and sleptons. This apparent puzzle is resolved in a natural way in gluino-driven radiative breaking of the electroweak symmetry where radiative breaking is driven by a large gluino mass and the gluino color interactions lead to a large splitting between the squarks and the sleptons. We show that an analysis without prejudice using an artificial neural network also leads to the gluino-driven radiative breaking. We use a set of benchmarks and a deep neural network analysis to test the model for the discovery of light sleptons and sneutrinos at HL-LHC and HE-LHC.
Variance reducing and noise correction in protein quantification by measuring fluctuations in fluorescence due to photobleaching
Authors: Gelber Itay
Published: March 2022

Quantifying the absolute protein number using the ratio between the variance and the mean of the protein Fluorescence intensity is a straightforward method for microscopy imaging. Recently, this method has been expanded to fluorescence decaying processes due to photobleaching with binomial distribution. The article examines the method proposed and shows how it can be adapted to the case of variance in the initial number of proteins between the cells. The article shows that the method can be improved by the implementation of the information processing of each frame independently from other frames. By doing so, the variance in determining the protein number can be reduced. In addition, the article examines the management of unwanted noises in the measurement, offers a solution for the shot noise and background noise, examines the expected error caused by the decay constant inaccuracy, and analyzes the expected difficulties in conducting a practical experiment, which includes a non-exponential decay and variance in the photobleaching rate of the cells. The method can be applied to any superposition of n
0 discrete decaying processes. However, the evaluation of expected errors in quantification is essential for early planning of the experimental conditions and evaluation of the error.
Nonextensive effects on QCD chiral phase transition with a chiral chemical potential*
Authors: Zhao Ya-Peng , Zuo Shu-Yu , Li Cheng-Ming
Published: March 2022

In this study, we investigate the QCD chiral phase diagram in the presence of a chiral chemical potentialbased on nonextensive statistical mechanics. A feature of this new statistic is a dimensionless nonextensivity parameterq, which summarizes all possible effects violating the assumptions of Boltzmann-Gibbs (BG) statistics (when, it returns to the BG case). Within the nonextensive Polyakov-Nambu-Jona-Lasinio model, we find that asincreases, the critical end point (CEP) in theplane continues toin theplane, and nonextensive effects have a significant impact on the evolution from the CEP to. Generally, with an increase inq, both the CEP andmove in the direction of a lower temperatureTand larger chemical potentialμ(). In addition, we find that chiral charge densitygenerally increases withT,μ,, andq. Our study may provide useful hints about lattice QCD and relativistic heavy-ion collision experiments.
Fibre-coupled tunable source based on a supercontinuum laser for the spectral characterisation of fibre optics components and systems
Authors: Castagna Natascia , Morel Jacques
Published: March 2022

We present a measurement system, traceable to the International System of Units, for the calibration of the spectral responsivity (SR) of fibre-coupled photodetectors and power meters, as well as for the measurement of the spectral properties of fibre optics components. The system, based on a supercontinuum laser combined with a two-stage tunable filter, is continuously tunable in a spectral range spanning from 700 nm to 1800 nm. The typical full width half maximum (FWHM) spectral width is of about 1.3 nm, with an in-fibre power level of up to 1 mW. In a single mode geometry, the expanded uncertainty is as low as 0.7% for the SR calibration and 0.6% for the spectral properties calibration. Uncertainties of about 1% were estimated for both types of measurements in a multi mode geometry. Application fields of this versatile system range from telecommunication to sensors and to rapidly growing domains like quantum communication and cryptography.
Development of an automated Moon observation system using the ALTS-07 Robotic Telescope: 2. Progress report on standard contrast enhancement of Moon crescent image with OpenCV
Authors: Muztaba Robiatul , Malasan Hakim L. , Djamal Mitra
Published: March 2022

Vision is a continuous two-dimensional (2-D) image that can be perceived by human visual system. Mathematically, image is a 2-D function that expresses the intensity of light. This research introduces the fundamental ideas of computer vision. We used OpenCV (Open-Source Computer Vision) to solve automatic image processing techniques, especially enhancement of contrast crescent visibility. We described an image using feature vectors to characterize and numerically to quantify the contents of an image. Then, we compared several techniques for increasing image quality, such as Basic contrast, Binary thresholding, Otsu thresholding, Histogram equalization, and Adaptive Histogram equalization. Finally, we calculated the statistical features of the image before and after enhancement process, and also decided to choose the best enhancement technique that will be implemented on a self-constructed cascade classifier in the future.
Space debris flux on LAPAN satellites during Solar Cycle 25
Authors: Rachman Abdul
Published: March 2022

Solar activity has been known to have impacts on the altitude of low Earth orbit satellites and space debris as well. Consequently, this will affect the flux of debris population around a satellite’s orbit. LAPAN currently has three satellites in low Earth orbit which will still be in operation during Solar Cycle 25 which began in December 2019 and is expected to reach the peak in 2025. It is widely known that even a very small debris can give detrimental effects to those satellites due to their hypervelocity speed. In the present study we report the space debris flux on LAPAN-TUBSAT, LAPAN A2, and LAPAN A3 satellites during the solar cycle. The flux is generated using ORDEM 3.1 released by NASA.