bluuebunny/crossref_metadata_2025 huggingface dataset:
Alanine response to low energy synchrotron x-ray radiation
Authors: van den Elzen P , Sander T , Palmans H , McManus M , Woodall N , Lee N , Fox O J L , Jones R M , Angal-Kalinin D , Subiel A
Published: February 2023

Objective. The radiation response of alanine is very well characterized in the MV photon energy range where it can be used to determine the dose delivered with an accuracy better than 1%, making it suitable as a secondary standard detector in cancer radiation therapy. This is not the case in the very low energy keV x-ray range where the alanine response is affected by large uncertainties and is strongly dependent on the x-ray beam energy. This motivated the study undertaken here. Approach. Alanine pellets with a nominal thickness of 0.5 mm and diameter of 5 mm were irradiated with monoenergetic x-rays at the Diamond Light Source synchrotron, to quantify their response in the 8–20 keV range relative to 60Co radiation. The absorbed dose to graphite was measured with a small portable graphite calorimeter, and the DOSRZnrc code in the EGSnrc Monte Carlo package was used to calculate conversion factors between the measured dose to graphite and the absorbed dose to water delivered to the alanine pellets. GafChromic EBT3 films were used to measure the beam profile for modelling in the MC simulations. Main results. The relative responses measured in this energy range were found to range from 0.616 to 0.643, with a combined relative expanded uncertainty of 3.4%–3.5% (k = 2), where the majority of the uncertainty originated from the uncertainty in the alanine readout, due to the small size of the pellets used. Significance. The measured values were in good agreement with previously published data in the overlapping region of x-ray energies, while this work extended the dataset to lower energies. By measuring the response to monoenergetic x-rays, the response to a more complex broad-spectrum x-ray source can be inferred if the spectrum is known, meaning that this work supports the establishment of alanine as a secondary standard dosimeter for low-energy x-ray sources.
Alfvén eigenmode stability in a JET afterglow deuterium plasma and projections to deuterium–tritium plasmas
Authors: Teplukhina A A , Podestà M , Poli F M , Gorelenkova M , Bonofiglo P J , Collins C S , Dumont R J , Hawkes N C , Keeling D L , Sertoli M , Szepesi G , Thorman A , Contributors JET
Published: February 2023

The performance of fusion devices relies strongly on the good confinement of energetic particles (EPs). Therefore, the investigation of EP transport by magnetohydrodynamic instabilities is one of the key aspects in the development of plasma scenarios. Alfvénic instabilities in particular can lead to significant losses of alpha particles that are essential for plasma self-heating. A so-called afterglow scheme has been developed to study the destabilization of Alfvén eigenmodes (AEs) by alpha particles and associated EP transport in the JET tokamak. In this work, the linear stability of AEs is discussed for the partial afterglow phase in a JET deuterium plasma discharge and for the full afterglow phase in a projected deuterium–tritium (DT) plasma. Thanks to recent upgrades in the tokamak transport code TRANSP, one can account for the contributions of different EP species to mode stability. Analysis of deuterium plasmas shows that AE growth rates are extremely sensitive to the energy and distribution of fast ions. An increase in fast ion energy can lead to more unstable AEs. In the afterglow phase of projected DT plasmas, it is EPs that mostly drive the AEs. However, the drive by alpha particles is comparable to that by beam ions and their contribution to the net growth rate might be hard to separate. According to the discussed projections, the destabilization of AEs might be ineffective because the background plasma damping significantly exceeds the EP drive. In this case, the development of an alternative plasma scenario that allows us to overcome such damping would be required in future experiments.
Rotating spokes and self-organization in an inductive pulsed plasma thruster
Authors: Sharma Arvindh R , Promislow Curtis L , Little Justin M
Published: February 2023

An experimental study of azimuthally rotating spokes in the plasma sheet of an inductive pulsed plasma thruster is presented. High-speed imaging reveals the formation of spokes with mode number ≈ 18 for a range of background pressure and coil discharge conditions. The spoke widths increase and the corresponding spoke orders decrease through an inverse cascade of energy flowing from higher-order to lower-order spokes, resulting in a more uniform plasma sheet. Secondary plasma sheets form in the half-cycle of the current discharge following primary sheet formation. It is observed that the plasma sheet forms earlier in the discharge as the pre-ionizer discharge energy increases, and increasing the background pressure results in higher uniformity when the other conditions are held constant. Spokes rotate predominantly in the

E
⃗

×

B
⃗

drift direction at speeds on the order of critical ionization velocity, and orders of magnitude smaller than the

E
⃗

×

B
⃗

drift speed. Simultaneously counter-rotating spokes are observed under various operating conditions.
Measurements for static shape control optimization of silicon mirror using nonlinear piezoceramic actuators
Authors: Sumit  , Kane S R , Ganguli Tapas , Shukla Rahul
Published: February 2023

In this paper, experimental study for shape control of silicon mirror is done by nonlinear piezoceramic actuator. A piezoelectric unimorph-based silicon mirror (PUSiM) is fabricated using APC 850 piezoceramic for shape control analysis. The piezo response function of all the actuators and profile of PUSiM are measured by confocal sensor at various applied electric fields to verify the nonlinearity of piezoceramic actuator. For comparison, electromechanical coupled finite element model of PUSiM is developed. Recently proposed iterative piezo response function-based optimization is used to calculate the electric field of piezoceramic actuators to achieve the target elliptical profile of PUSiM. At optimum voltage the achieved profile of PUSiM is quite close to the target elliptical profile with 193 nm root-mean-square error. Knowing the nonlinearity inherent in the piezoceramic actuators at high voltages the proposed measurement technique is a way forward for the shape control of structures and deformable mirrors.
Preparation and processing performance of high steady-state magnetorheological finishing fluid
Authors: Shen Zhuoshan , Pan Jisheng , Zhang Jianwen , Yan Qiusheng
Published: February 2023

Magnetorheological finishing fluid (MRFF), as the transfer medium of magnetorheological finishing, is mainly composed of magnetic particles, base carrier fluid, abrasives and additives, etc. The MRFF with stable performance and good polishing effect is an important factor to achieve magnetorheological deterministic finishing. The magnetic particles with low bulk density are stably suspended in the MRFF, while the micro-structure on the outer surface of the magnetic particles can enhance the holding strength of the magnetic chain bundles on the abrasives in magnetorheological finishing. Highly stable MRFF was prepared by combining solvothermal and calcination reactions to produce flower-like Fe3O4 as magnetic particles, and its settling stability and polishing performance were tested. The stability test results showed that the settling ratio of 64.2% for the flower-like-Fe3O4 MRFF was better than that of 14.2% for the spherical Fe3O4. Compared with the spherical-Fe3O4 magnetic chain bundles, the COMSOL Multiphysics finite element simulation results showed that the magnetic chain bundles composed of flower-like Fe3O4 had a stronger holding force under the magnetic field and a 10.37% increase in shear force during the polishing process. The processing results showed that the polishing depth of flower-like Fe3O4 polishing increased with the gradual reduction of polishing gap, and the polishing with flower-like-Fe3O4 MRFF could obtain deeper material removal depth compared with spherical-Fe3O4 MRFF, and the maximum removal depth increased by 41.5% under the same conditions.
Study on new magnetorheological chemical polishing process for GaN crystals: polishing solution composition, process parameters, and roughness prediction model
Authors: Wu Jinzhong , Afzal Burhan , Huang Zhilong , Yang Maoju , Sun Shuaishuai
Published: February 2023

High-quality and high-efficiency processing of gallium nitride (GaN) crystals is urgently required for optoelectronic communications and other major industries. This study proposes a novel high-efficiency non-damage magnetorheological chemical polishing (MCP) process to overcome the existing problems of low efficiency and lattice distortion during processing. The effects of the MCP fluid composition and key processing parameters on the surface roughness and material removal rate (MRR) of GaN crystals were studied experimentally. The results showed that a compounded abrasive containing silica fluid exhibited better polishing effects than a single abrasive. The polishing efficiency could be improved by adding NaOH solid particles, and the MRR reached 13.19 nm min−1 when the pH of the MCP fluid was 10. The MRR increased gradually with an increase in the pole rotation speed and worktable speed and a decrease in the polishing gap. The surface roughness of the GaN crystals was improved from Ra 115 nm to Ra 0.375 nm after polishing for 4 h. The surface and sub-surface damage of the polished GaN crystals was analyzed using scanning electron microscope and transmission electron microscope. The results confirmed that the MCP process can realize the non-damage polishing of GaN crystals. Moreover, a prediction model for the surface roughness of GaN crystals in the MCP process was constructed. The overall difference between the actual and predicted surface roughness values for the model was 11.6%.
On the characterization of the compressive response of shape memory alloys using bending
Authors: Mohammad Hashemi Yadollah , Kadkhodaei Mahmoud , Sgambitterra Emanuele , Maletta Carmine
Published: February 2023

Determination of material parameters of metals/polymers under compressive loadings has been sometimes an onerous issue especially for thin sheets and wires. In the present paper, an approach is presented to determine the compressive material constants of the shape memory alloy (SMA) sheets by employing four-point bending tests. A three-dimensional (3D) asymmetric model is presented and implemented in COMSOL software. An SMA strip showing pseudoelasticity at the ambient temperature is trained under tensile loading, and the experimental results are used together with the model to determine the tensile material parameters of the specimen. On the other hand, a sample is subjected to four-point bending, and, after training, the strain distribution at the lateral surface of the sample is captured by using digital image correlation method. The empirical results for bending are utilized along with 3D simulations to determine the compressive material parameters of the specimens. The approach is finally validated by experimental data, and it appears to provide a reliable procedure for the compressive characterization of SMAs. The present research enables users to avoid performing susceptible compression tests and also empowers them to study the compressive mechanical response of a material during training cycles under quasi-static/adiabatic conditions.
Analysis of inhomogeneities in Nb3Sn wires by combined SEM and SHPM and their impact on J
c and T
c
Authors: Pfeiffer S , Baumgartner T , Löffler S , Stöger-Pollach M , Hopkins S C , Ballarino A , Eisterer M , Bernardi J
Published: February 2023

We demonstrate the combined use of scanning electron microscopy (SEM) and scanning Hall probe microscopy (SHPM) to analyse inhomogeneities in Nb3Sn wires. Inhomogeneities of the A15 phase in Nb3Sn sub-elements of a Ti-alloyed Restacked Rod Process wire and a Ta-alloyed Powder-In-Tube wire are investigated. Microstructural features are examined by SEM, elemental concentration gradients by energy dispersive x-ray spectroscopy (EDX) and the superconducting properties by SHPM. Correlations between the results are analysed to gain information about the impact of inhomogeneities in the microstructure on the superconducting properties. We find considerable differences in geometry and performance between sub-elements, as well as compositional and geometric inhomogeneities of the A15 phase inside single sub-elements. Additionally, simulations of the influence of Sn concentration gradients on the critical current density J
c are performed. We also demonstrate the viability of SHPM and EDX for determining the dependence of the critical temperature T
c on the Sn concentration and discuss possible performance gains by a reduction of inhomogeneities in Nb3Sn wires.
How to build a magnetometer with thermal atomic vapor: a tutorial
Authors: Fabricant Anne , Novikova Irina , Bison Georg
Published: February 2023

This article is designed as a step-by-step guide to optically pumped magnetometers based on alkali atomic vapor cells. We begin with a general introduction to atomic magneto-optical response, as well as expected magnetometer performance merits and how they are affected by main sources of noise. This is followed by a brief comparison of different magnetometer realizations and an overview of current research, with the aim of helping readers to identify the most suitable magnetometer type for specific applications. Next, we discuss some practical considerations for experimental implementations, using the case of an M

z
magnetometer as an example of the design process. Finally, an interactive workbook with real magnetometer data is provided to illustrate magnetometer-performance analysis.
Nonlocal couple stress-based quasi-3D nonlinear dynamics of agglomerated CNT-reinforced micro/nano-plates before and after bifurcation phenomenon
Authors: Yue Xiao-Guang , Sahmani Saeid , Safaei Babak
Published: February 2023

In present research exploration, the nonlinear dynamic stability characteristics of axially compressed nanocomposite plates at micro/nano-scale reinforced with randomly oriented carbon nanotubes (CNTs) are investigated within the both prebuckling and postbuckling regimes. To accomplish this examination, the nonlocal couple stress (NCS) continuum elasticity is incorporated to a quasi-3D plate theory which separates the plate deformation to the bending and shear parts considering simultaneously the transverse shear and normal displacements. In addition, a two-parameter homogenization scheme is utilized to obtain the effective characters of the randomly oriented CNT-reinforced nanocomposites. The NCS-based nonlinear differential equations of motion are discretized using the Kronecker tensor product together with the shifted Chebyshev-Gauss-Lobatto gridding pattern. Thereafter, the Galerkin technique together with the pseudo arc-length continuation method are employed to achieve the NCS-based fRequency-load and nonlinear frequency ratio-deflection curves before and after of the bifurcation point. It is deduced that for a randomly oriented CNT-reinforced heterogeneous micro/nano-plate in which the most CNTs are located inside clusters, increasing the value of cluster volume fraction leads to increase a bit the significance of the softening and stiffing characters related to the nonlocal and couple stress tensors before the bifurcation phenomenon, but it causes to decrease them after the critical bifurcation point. Opposite patterns before and after the bifurcation phenomenon are predicted for the agglomeration in which the most CNTs are located outside clusters.
Plasmon resonances of graphene-assisted core-bishell nanoparticles
Authors: Fares Hesham , Ahmed Moustafa , Moustafa Samar
Published: February 2023

We study the Localized Surface Plasmon Resonance (LSPR) in graphene-assisted core-bishell nanoparticles which consist of a graphene layer (outer shell) wrapped around a metal shell and either a dielectric or a metal core. Small nanoparticles with a size much smaller than the wavelength of incident light are assumed, and the quasi-static approximation is applied to develop analytic equations to describe the absorption, scattering, and extinction efficiencies . The proposed nanostructures exhibit two LSPRs; one is in the visible range and corresponds to a plasmon mode of the core-inner shell composite, while the second lies in the near infrared (NIR) and is induced by the graphene plasmons excited at the outer shell. Interestingly, the LSPR of graphene has an ultra-narrow bandwidth and can be tuned in the NIR by altering the physical parameters of graphene, such as the Fermi energy and the number of graphene layers. Therefore, the LSPR peak of graphene is promising for medical applications. In addition, the LSPR of graphene can be tuned to the visible range near the position of the first LSPR, resulting in two narrow linewidth peaks. These resonance peaks could be beneficial for highly sensitive LSPR-based sensors.
Synthesis of CuO thin films by a direct current reactive sputtering process for CO gas sensing application
Authors: Mahana Debashrita , Mauraya Amit Kumar , Kumaragurubaran Somu , Singh Preetam , Muthusamy Senthil Kumar
Published: February 2023

A direct current magnetron reactive sputtering, one of the well-known physical vapour deposition (PVD) techniques, was employed for the preparation of CuO thin films at room temperature for CO gas sensing application. The effect of the O2 gas flow ratio on the phase formation of copper oxide was studied by varying the O2 flow rate in the total flow of Ar/O2 gas mixture. Cu2O phase was found to form at a low O2 flow ratio of 10% and gradually converted into stable CuO phase with an increase in O2 flow ratio through the intermediate phase of Cu4O3. The films exhibited a granular morphology, and the average grain size increased with an increase in the O2 partial flow. Single-phase CuO thin film has been obtained with 40% of O2 gas flow ratio. The evolution of the copper oxide phases with increasing O2 partial flow was also confirmed using the Cu 2p and O 1s core-levels of X-ray photoelectron spectroscopy. The CO gas sensing characteristics of the CuO thin film were examined by varying the operating temperature in the range of 200 °C–400 °C. An optimized CO sensing response of 127% has been obtained at 375 °C towards 91 ppm concentration with a response/recovery time of 161 s/99 s.
Soliton rains with isolated solitons induced by acoustic waves in a nonlinear multimodal interference-based fiber laser
Authors: Chen G W , Jia K L , Ji S K , Zhu J , Li H Y
Published: February 2023

We experimentally and theoretically demonstrate soliton rains with isolated solitons and soliton bunches in a passively mode-locked fiber laser, using a mode-locker based on a nonlinear multimodal interference technique. The isolated solitons are captured at the moments of integer multiples of 21 ns and 33 ns, which correspond to the acoustic modes in TR2m and R0m branches. The theory of nonlinear fiber optics is used to characterize the mechanism of capturing isolated solitons. The modal delay induced by the multimode fiber gives a revealing insight into the loss of capacity to capture and transition from soliton rains to bunches. Our study introduces a new way to precisely control the behaviors of multi-solitons and provides a potential tool for understanding complex nonlinear dynamics.
Elemental study of Devarda’s alloy using calibration free-laser induced breakdown spectroscopy (CF‒LIBS)
Authors: Iqbal Javed , Alrebdi Tahani A , Fayyaz Amir , Asghar Haroon , Shah Syed Kifayat H , Naeem M
Published: February 2023

In the present study, we present the compositional analysis of a Devarda’s alloy using the calibration–free laser-induced breakdown spectroscopy (CF-LIBS) technique. A nanosecond pulsed Q-switched Nd:YAG laser was focused on the target-sample under investigation to ablate its surface and the measured emission spectrum was registered by using a spectrometer (LIBS2000+) having the optical spectral within a range from 200–720 nm. The analysis of the measured optical spectra confirms the presence of three major elements Aluminum (Al), Copper (Cu), and Zinc (Zn) in the target sample. The emission intensity line profiles of Zn, Cu, and Al were utilized to estimate the plasma-parameters consisting of excitation temperature, and the plasma number density. The plasma excitation temperature was investigated using the Boltzmann-plot technique, which yields the temperature for Cu and Zn as 8547 ± 5% K and 8100 ± 5%, respectively, while the electron plasma density was calculated from the Stark-broadening of individual neutral emission lines of Al, Cu, and Zn. For the quantitative analysis of the elements that exist in the target sample, a CF-LIBS technique was employed by assuming the condition of optically thin plasma as well as local thermodynamics equilibrium. Using the CF-LIBS technique, the relative composition in the form of weight percentage was estimated to be Zn: 57%, Al: 39%, and Cu: 4%, whereas, the certified concentration of Devarda’s alloy was 50% for Zn, 45% for Al, and 5% for Cu. These measured results reveal that the elemental concentration utilizing CF-LIBS shows a reasonable agreement with standard estimates illustrated by the manufacturer. This study further suggests that the CF-LIBS technique opens up an opportunity for engineering and industrial usage of LIBS where a quantifiable study of the substance is exceedingly advantageous.
Exact magnetic properties of two-dimensional spin-1 Cooper pairs
Authors: Cheng Ze
Published: February 2023

Exact magnetic properties of two-dimensional (2D) spin-1 Cooper pairs are investigated within the framework of quantum statistical mechanics. We derive an exact analytical expression of the magnetization of 2D spin-1 Cooper pairs, which involves a q-digamma function and a q-Pochhammer symbol in mathematics. The magnetization density m(T) is a function of temperature T, Landé factor g, number density σ, and magnetic field B. Firstly, we examine the evolution of the magnetization density m(T) with the Landé factor g. m(T) is negative when g < 1, and changes gradually to positive after g

c
. Here,

g
c

=
1

is the critical value of the Landé factor g, at which

m
(
T
)
=
0

. Secondly, we examine the evolution of the magnetization density m(T) with the temperature T. When g < 1, there are the two asymptotic lines for the magnetization density m(T). The low-temperature asymptotic line is

m
(
T
)
=
−
387.5

 nC s−1 and the high-temperature asymptotic line is

m
(
T
)
=
0

. Finally, we examine the evolution of the magnetization density m(T) with the number density σ. No matter how large the Landé factor g is, there is a lower cutoff σ

c
of the number density σ. The lower cutoff number density is about

σ
c

=

10

12

 cm−2. If

σ
<

σ
c

, the Cooper pair system does not support a solution of the reduced chemical potential x. As the number density σ is increased, the Bose–Einstein condensation of 2D Cooper pairs is strengthened.
Data-driven design of the Belle II track segment finder
Authors: Unger K.L. , Neu M. , Becker J. , Schmidt E. , Kiesling C. , Meggendorfer F. , Skambraks S.
Published: February 2023

The Belle II experiment relies on a level-1 trigger system to reduce noise background and preselect events of interest for particle physics. The Central Drift Chamber is the main track detector which makes its trigger system important for online track reconstruction. To improve its hit efficiency, an extension of the track segment finder for low angle tracks is proposed. By combining hardware and software development flows, an automated data-driven pipeline is created and three different-sized hardware concepts are implemented. The operation point is adjustable to balance hit efficiency against hit purity in the trigger system.
Evidence map of the benefits of enhanced-efficiency fertilisers for the environment, nutrient use efficiency, soil fertility, and crop production
Authors: Chen Mathilde , Schievano Andrea , Bosco Simona , Montero-Castaño Ana , Tamburini Giovanni , Pérez-Soba Marta , Makowski David
Published: February 2023

The identification of sustainable fertilisation practices is essential to reduce agriculture’s impact on the environment while insuring sufficient crop production. The use of enhanced efficiency fertilisers (EEFs) is thought to improve nitrogen (N)-fertiliser uptake by crops while reducing nutrient losses to the environment. EEFs’ performance has been assessed in several meta-analyses and systematic reviews, which are heterogeneous in content and quality of reporting. This provides fragmented information and makes it difficult to conclude about their ability to provide more sustainable fertilisation. Here we synthetise evidence from 26 meta-analyses and reviews selected by a systematic literature search to describe the separate effects of four commonly used EEFs—nitrification inhibitors, urease inhibitors, double inhibitors, or controlled-release fertilisers—on the environment, nutrient use efficiency, soil fertility, and crop production. A unique contribution of this review is the assessment of the quality of the selected papers and the synthesis of their results through a systematic framework. Results showed that compared to conventional fertilisers, EEFs generally increased soil nutrients, crop yield, and N use efficiency, and reduced N leaching, emissions of greenhouse gases and air pollutants. Some differences were found between the different EEFs; while urease inhibitors, double inhibitors, and controlled-released fertilisers decreased ammonia emission compared to conventional fertilisers, nitrification inhibitors increased these emissions or did not affect them. The results were consistent when excluding low-quality studies from the analyses. Overall, this global synthesis indicates that EEFs could maintain crop yields while reducing some of the negative environmental impacts of conventional N-fertilisers. Attention should be paid to the potential increase of ammonia emissions by nitrification inhibitors and additional evidence is needed on the potential side effects on soil health, biodiversity, and water quality.
Seismic Site Response Analysis of MMMUT Gorakhpur of Uttar Pradesh, India
Authors: Yadav Shubhamjeet , Maurya Madan Chandra , Sharma Keshav Kumar
Published: February 2023

An endeavour has been made to assess the spatial fluctuation of the profundity of endured and designing bedrock in Gorakhpur Uttar Pradesh, North India utilizing Multichannel Analysis of Surface Wave (MASW) study. One-layered MASW study has been done at Madan Mohan Malaviya University of Technology, Gorakhpur campus and Shear-wave VelocityVS30are estimated. MASW overview at 3 location and a Standard Penetration Test SPT-N from the profound geotechnical boreholes data used for comparison of site classification. The deduction of this work might be utilized as contributions for seismic tremor risk the board by lessening the seriousness of earthquake shaking through plan of tremor Earthquake risk resilient structure strong designs. The data that collected from the MASW experimental setup is feed using the software ParkSEIS (v.3.0), we obtain Shear Wave Velocity (VS30). The obtainedVS30is used to plot Response Spectra for MMMUT Gorakhpur. The Time History data used in this thesis is Nepal Earthquake 2015 data which is collected from Indian Metrological Department (IMD) Delhi, India. SPT-N value data is collected from Awas Vikas Parishad for the New Administration Building build at MMMUT campus Gorakhpur. The Time History data of Nepal Earthquake 2015 is analysed using DEEPSOIL v7 Software and a systematic layer wise study of MMMUT Campus soil is carried out, results such as Ground Motion Parameters, Response Spectra, Spectral acceleration vs Frequency plot, Tripartite Spectrum and Response spectra corresponding to 5% damping are obtained.
Experimental Study on the Crack Repair Techniques of Concrete Structures: A Case Study
Authors: Bano Samreen , Jaiswal Ganesh , Kumar Rikshit , Tiwari Avneesh , Karthikeyan M
Published: February 2023

A crack is a whole or partial split of either concrete or masonry into two or more portions caused by breaking or fracturing in concrete constructions. The bulk of fractures is caused by external forces higher than what the structure or its components can sustain acting on it. The most typical sign of degradation in concrete buildings is cracking. Once the fractured system has been assessed, an appropriate repair method that considers these reasons may be chosen. Selecting the best crack repair method may produce results that endure for a very long time while saving you a lot of time, money, and effort. The causes of cracks and several strategies for healing them are covered in this paper.
Creation of optical chains with prescribed characteristics
Authors: Zeng Yongxi , Yu Yanzhong , Zhan Qiwen
Published: February 2023

We report a non-iterative method to create an arbitrarily spatially-orientated optical chain with prescribed characteristics through the use of antenna radiation theory and time reversal methodology. A pair of antennas consisting of an electric current line source (ELS) and a magnetic current line source (MLS) are employed to yield the required incident field pattern for

4
π

focusing system. Numerical results demonstrate that the direction of the generated optical chain is consistent with the orientation of the combined antennas, and the length of the optical chain is approximately equal to the length of the combined antennas, and the amount, position and spacing of the dark hollow spots are determined by the length of the combined antenna and the amplitude periodic coefficient of the ELS. The generated optical chains may find potential applications in multi-points optical capture and particle delivery along prescribed directions.
Image-plane coherent diffractive imaging using variable-ratio lateral-shearing interferometry
Authors: Zhou Mengyu , Zhang Xiuping , Zhang Junyong , Zhu Jianqiang
Published: February 2023

Coherent diffractive imaging (CDI) is an imaging technique that directly recovers the amplitude and phase information of the test object from the recorded diffraction patterns with an iterative algorithm. Different from the traditional CDI, here an image-plane CDI is proposed based on the variable-ratio lateral-shearing interferometry. Variable-ratio operation can realize three optical functions, the first is the array imaging, the second is the image relay, and the third is variable-ratio shear. In experiment, a frame of

2
×
2

array diffraction patterns is recorded in one single exposure. Then, each sub-diffraction pattern is extracted through the image features and is sequentially used to recover the test object by phase retrieval. The experimental results of phase-only and amplitude-only object verify the effectiveness and robustness of our proposed method. This method not only circumvents the calibration problem of gratings but also strengthens the convergence conditions required for phase retrieval, which has broad applications in fields such as optical imaging and wavefront sensing.
Recent advances in hole-spin qubits
Authors: Fang Yinan , Philippopoulos Pericles , Culcer Dimitrie , Coish W A , Chesi Stefano
Published: February 2023

In recent years, hole-spin qubits based on semiconductor quantum dots have advanced at a rapid pace. We first review the main potential advantages of these hole-spin qubits with respect to their electron-spin counterparts and give a general theoretical framework describing them. The basic features of spin–orbit coupling and hyperfine interaction in the valence band are discussed, together with consequences on coherence and spin manipulation. In the second part of the article, we provide a survey of experimental realizations, which spans a relatively broad spectrum of devices based on GaAs, Si and Si/Ge heterostructures. We conclude with a brief outlook.
The Management of Lumps, Bumps, and Contour Irregularities of the Lower Eyelid and Cheek After Poor Outcome Fat Transfer
Authors: Ugradar Shoaib , Wang Yao , Patel Amy , Holds John B , Douglas Raymond , Massry Guy
Published: February 2023

Background

The increasing popularity of fat transfer (FT) to the lower eyelids has led to an increase in unwanted lumps, bumps, and contour irregularities (LBCs). Few studies have addressed the management of LBCs.

Objectives

The aim of this study was to address the management of LBCs.

Methods

In this retrospective review, charts of all patients presenting for evaluation of LBCs following FT procedures to the lower eyelid were reviewed. Clinical characteristics on presentation and surgical findings were evaluated. Patient postoperative clinical course and complications were also documented.

Results

Forty-eight patients were included (45 women and 3 men), with an average follow-up of 14 months (range, 5-24 months). In 65%, LBCs manifested above the lower orbital rim (AR) and in 35% they were noted AR and below the rim (AR/BR). The type of contour deficits noted were a solitary nodule (SN) in 54%, a mixed picture (MP) in 23%, diffuse enlargement (DE) in 17%, and multiple nodules (MNs) in 6%. Combining lesion location and type of contour deficit, the most common presentation was an SN-AR in 22 patients (46%), followed by an MP-AR/BR in 8 patients (17%), and a DE-AR/BR in 5 patients (10%). Surgical findings revealed that grafted fat is consistently found separate from native eyelid/orbital fat, and within the orbicularis muscle when AR, and within the orbicularis muscle or the deep suborbicularis oculi fat when BR.

Conclusions

LBCs tend to manifest in characteristic patterns with a predilection for an AR location. Recommendations on the diagnosis and management of these lesions are provided.
An experimental field test of female defense in territorial male collared lizards
Authors: Baird Troy A , Leibold Dalton C
Published: February 2023

A widely held principle in behavioral ecological research is that polygynous social systems evolve either by direct male defense of females or male defense of resources, although which of these mechanisms applies in particular species is rarely examined experimentally. We tested the relative importance of female versus resource defense in polygynous territorial male collared lizards (Crotaphytus collaris). Using a novel experimental design, we temporarily removed some of the resident females from male territories to create a female-free removal zone, whereas resident females were left intact within a non-removal zone. We then compared activity of males within each zone during three experimental phases; before we removed females, for two days when females were absent, and the day after return of females. If males defend females directly, we expected them to adjust the location of their patrol and display within removal and non-removal zones depending on the presence/absence of females, whereas we expected no such change if males defend resources. Male activity in the removal zone generally decreased when females were removed but then increased when females were replaced, whereas we observed the opposite pattern in the non-removal zone. The observed shifts in the location of patrol and display in response to the presence/absence of females, while resources remained constant, indicate that polygynous male collared lizards defend females directly. Our results suggest that male collared lizards take advantage of strong female philopatry to relatively small areas by focusing their patrol and display activities where potential mates reside.
Improving classification of correct and incorrect protein–protein docking models by augmenting the training set
Authors: Barradas-Bautista Didier , Almajed Ali , Oliva Romina , Kalnis Panos , Cavallo Luigi
Published: February 2023

Motivation

Protein–protein interactions drive many relevant biological events, such as infection, replication and recognition. To control or engineer such events, we need to access the molecular details of the interaction provided by experimental 3D structures. However, such experiments take time and are expensive; moreover, the current technology cannot keep up with the high discovery rate of new interactions. Computational modeling, like protein–protein docking, can help to fill this gap by generating docking poses. Protein–protein docking generally consists of two parts, sampling and scoring. The sampling is an exhaustive search of the tridimensional space. The caveat of the sampling is that it generates a large number of incorrect poses, producing a highly unbalanced dataset. This limits the utility of the data to train machine learning classifiers.

Results

Using weak supervision, we developed a data augmentation method that we named hAIkal. Using hAIkal, we increased the labeled training data to train several algorithms. We trained and obtained different classifiers; the best classifier has 81% accuracy and 0.51 Matthews’ correlation coefficient on the test set, surpassing the state-of-the-art scoring functions.

Availability and implementation

Docking models from Benchmark 5 are available at https://doi.org/10.5281/zenodo.4012018. Processed tabular data are available at https://repository.kaust.edu.sa/handle/10754/666961. Google colab is available at https://colab.research.google.com/drive/1vbVrJcQSf6\_C3jOAmZzgQbTpuJ5zC1RP?usp=sharing

Supplementary information

Supplementary data are available at Bioinformatics Advances online.
WMDS.net: a network control framework for identifying key players in transcriptome programs
Authors: Cheng Xiang , Amanullah Md , Liu Weigang , Liu Yi , Pan Xiaoqing , Zhang Honghe , Xu Haiming , Liu Pengyuan , Lu Yan
Published: February 2023

Motivation

Mammalian cells can be transcriptionally reprogramed to other cellular phenotypes. Controllability of such complex transitions in transcriptional networks underlying cellular phenotypes is an inherent biological characteristic. This network controllability can be interpreted by operating a few key regulators to guide the transcriptional program from one state to another. Finding the key regulators in the transcriptional program can provide key insights into the network state transition underlying cellular phenotypes.

Results

To address this challenge, here, we proposed to identify the key regulators in the transcriptional co-expression network as a minimum dominating set (MDS) of driver nodes that can fully control the network state transition. Based on the theory of structural controllability, we developed a weighted MDS network model (WMDS.net) to find the driver nodes of differential gene co-expression networks. The weight of WMDS.net integrates the degree of nodes in the network and the significance of gene co-expression difference between two physiological states into the measurement of node controllability of the transcriptional network. To confirm its validity, we applied WMDS.net to the discovery of cancer driver genes in RNA-seq datasets from The Cancer Genome Atlas. WMDS.net is powerful among various cancer datasets and outperformed the other top-tier tools with a better balance between precision and recall.

Availability and implementation

https://github.com/chaofen123/WMDS.net.

Supplementary information

Supplementary data are available at Bioinformatics online.
Dimethyl-α-cyclodextrin induces capacitation by removing phospholipids from the plasma membrane of mouse sperm
Authors: Nakao Satohiro , Ito Kotono , Sakoh Kazuhito , Takemoto Kenji , Watanabe Hitomi , Kondoh Gen , Irie Tetsumi , Nakagata Naomi , Takeo Toru
Published: February 2023

Capacitation is an important event in the completion of fertilization by mammalian sperm. Cholesterol efflux is a trigger of capacitation. In general, cholesterol acceptors of albumin and β-cyclodextrins are used to induce capacitation during in vitro fertilization. Previously, we reported that methyl-β-cyclodextrin (MBCD), which is composed of seven glucoses, had a higher ability to induce capacitation than bovine serum albumin (BSA) in frozen–thawed mouse sperm. Comparison of albumin and cyclodextrins is helpful for understanding the mechanism of capacitation. In this study, we examined the effects of albumin, MBCD, and a different type of cyclodextrin, dimethyl-α-cyclodextrin (DMACD), which is composed of six glucoses, on several events of sperm capacitation. We showed that DMACD induced sperm capacitation and promoted fertilization ability. The time required to increase the fertilization rate differed among BSA, MBCD, and DMACD. BSA and MBCD enhanced cholesterol and phospholipid efflux, whereas DMACD enhanced only phospholipid efflux. BSA, MBCD, and DMACD increased sperm membrane fluidity, rearrangement of the lipid raft, and the acrosome reaction. These findings suggest that phospholipid efflux is a novel trigger of capacitation. Increasing the choice of sperm capacitation inducers may be useful for improving in vitro fertilization (IVF) techniques not only in mice, but also in various species in which it has been difficult to produce embryos by IVF.
Standard follow-up after curative surgery for advanced gastric cancer: secondary analysis of a multicentre randomized clinical trial (KLASS-02)
Authors: Park Sin Hye , Hyung Woo Jin , Yang Han-Kwang , Park Young-Kyu , Lee Hyuk-Joon , An Ji Yeong , Kim Wook , Kim Hyoung-Il , Kim Hyung-Ho , Ryu Seung Wan , Hur Hoon , Kim Min-Chan , Kong Seong-Ho , Cho Gyu Seok , Kim Jin-Jo , Park Do Joong , Kim Young-Woo , Kim Jong Won , Lee Joo-Ho , Han Sang-Uk , Ryu Keun Won
Published: February 2023

Background

The benefit of regular follow-up after curative resection for gastric cancer is controversial as there is no evidence that it will improve survival. This study assessed whether regular follow-up leads to improved survival in patients after surgery for gastric cancer.

Methods

A secondary analysis was undertaken of patients who participated in an RCT of laparoscopic versus open distal gastrectomy for advanced gastric cancer between November 2011 and April 2015. Depending on whether patients were compliant with the initial trial follow-up protocol or not, they were analysed as having had either regular or irregular follow-up. Clinicopathological characteristics, recurrence patterns, detection, treatments, and survival were compared between the groups.

Results

The regular and irregular follow-up groups comprised 712 and 263 patients respectively. Disease recurrence within 36 months was more common in the regular group than in the irregular group (17.0 versus 11.4 per cent; P = 0.041). Recurrence patterns did not differ between the groups. The 3-year recurrence-free survival rate was worse in the regular than in the irregular group (81.2 versus 86.5 per cent; P = 0.031). However, the 5-year overall survival rate was comparable (84.5 versus 87.5 per cent respectively; P = 0.160). Multivariable analysis revealed that type of follow-up was not an independent factor affecting 5-year overall survival.

Conclusion

Regular follow-up after radical gastrectomy was not associated with improved overall survival.
Comment on: Complete mesocolic excision for right colonic cancer: prospective multicentre study
Authors: Akyol Cihangir , Kuzu Mehmet A
Published: February 2023

This is a correspondence letter to the editor about the article entitled “Complete mesocolic excision for right colonic cancer: prospective multicentre study” published in BJS.
Children and bioethics: clarifying consent and assent in medical and research settings
Authors: Spriggs Merle
Published: February 2023

Introduction

The concept of consent in the pediatric setting is complex and confusing. Clinicians and researchers want to know whose consent they should obtain, when a child can provide independent consent and how that is determined. The aim of this article is to establish what produces the justification to proceed with medical or research interventions involving children and the role of consent in that. I clarify concepts such as consent, assent, capacity and competence.

Source of data

Literature review.

Areas of agreement

Engaging with children and involving them in decisions about matters that affect them is a good thing.

Areas of controversy

The role of competence or capacity and the question of when a child can provide sole consent.

Growing points

Flawed assumptions around competence/capacity.

Areas for developing research

An account of children’s well-being that accommodates children’s interests during the transition to adulthood.
Untangling the Hymenaea stigonocarpa complex (Fabaceae) using population genetics and morphology
Authors: Pinto Rafael Barbosa , Braga Ferreira Ramilla Dos Santos , Rosa Gonçalves Ariany , Telles Mariana Pires De Campos , José Chaves Lázaro , Alves Rezende Andréia , Diniz-Filho José Alexandre Felizola , Mansano Vidal De Freitas
Published: February 2023

Hymenaea is a genus of Fabaceae easily recognized by vegetative characteristics. However, the circumscription of some species has been historically challenging. The tangled circumscription of H. stigonocarpa has been addressed in several molecular and morphological studies, but some of the morphological confusion has yet to be resolved. Thus, in this study we used population genetics coupled with detailed morphological analyses to improve taxonomic definition in this complex, currently comprising two varieties (H. stigonocarpa vars. stigonocarpa and brevipetiolata). Bayesian and population genetic structure analyses were conducted using nine nuclear microsatellite loci for 1034 individuals from 35 populations. The morphometric analyses were performed using leaflet characters. Our results support the existence of five genetically structured clusters, and morphometric analyses support the recognition of two clusters, emphasizing H. stigonocarpa var. brevipetiolata as an exclusive genetic and morphological group, encouraging us to make changes in its taxonomic ranking. Thus, we propose the adoption of specific status for H. stigonocarpa var. brevipetiolata on the basis of its population genetics and morphology. In addition to the population genetics data and morphological analyses, a taxonomic treatment with illustrations is provided.