bluuebunny/crossref_metadata_2025 huggingface dataset:
Neonatal Ampicillin/Gentamicin Exposure and the Risk of Childhood Obesity in South Bronx Pediatric Population
Authors: Awujoola Adeola , Torga Ana Patricia , Abdul Ghayum Mohamed Aashiq , Mousa Nadeem , Olorunsogo Tolulope , DeSilva Samantha , Avades Meriam , Prince Olaseni , Ankola Pratibha
Published: September 2023

Objective This study aimed to assess the association between neonatal antibiotic exposure and the risk of childhood obesity.

Study Design This retrospective cohort study enrolled neonates born between 2011 and 2015 and followed up until 5 years. The incidence of obesity at 5 years old, and other characteristics were compared between the antibiotic-exposed and unexposed groups. Chi-square test was conducted on categorical variables and Student's t-test for normally distributed continuous variable. Significant variables (p < 0.05) in bivariate analysis were modelled in a stepwise multivariate logistic regression analysis to ascertain independent predictors of obesity at 5 years.

Results Of the 1,447 subjects, 749 (51.8%) received ampicillin and gentamicin, and 333 (23%) were obese. Neonates exposed to antibiotics were more likely to be obese compared with those unexposed (26 vs. 20%, p = 0.01). In the adjusted model, this association persisted (adjusted odds ratio: 1.37, p = 0.02).

Conclusion Neonatal antibiotic exposure is associated with early childhood obesity and may play a significant role in the weight trajectories of these children. Hence, antibiotic stewardship in this period cannot be overemphasized.

Key Points
Three-Dimensional Morphometric Analysis of Anterior Cerebral Circulation Aneurysms
Authors: Saal-Zapata Giancarlo , Walker Melanie , Cervantes-Medina Rosa , Rodríguez-Varela Rodolfo
Published: September 2023

This article assesses the association between anterior circulation morphometry and the presence of intracranial aneurysm using three-dimensional rotational angiography (3DRA). A retrospective analysis at a Peruvian academic medical center between December 2018 and February 2020 identified 206 patients with unruptured intracranial aneurysms and matched controls who underwent 3DRA. Angiographic images were obtained per standard of care, and measurements of the vasculature were performed using 3DRA vascular automated software. A total of 163 aneurysms and 43 control angiograms were evaluated. Women represented 82.5% of the cases and the mean age was 55.9 years (standard deviation ± 14.2). In multivariate analysis, five specific features were found to be statistically significant predictors for presence of an anterior circulation aneurysm: female sex (odds ratio [OR] = 2.71; p = 0.048), C-shape of the middle cerebral artery (MCA) (OR = 2.73; p = 0.018), distal internal carotid artery (ICA) diameter (OR = 3.42; p = 0.012), ICA bifurcation angle (OR = 1.02; p = 0.036), and length of the carotid siphon (OR = 1.08; p = 0.047). Features detected on 3DRA suggest morphological characteristics of the ICA and MCA may be predictive for intracranial aneurysm. Our findings build from prior reports by demonstrating five specific patient and imaging features associated with anterior circulation aneurysms. While 3DRA is the standard of care in many settings, medical centers with resource limitations may not have access to this technique. The demographic and morphological features identified in our study may have correlates that if detected on contrast computed tomography or magnetic resonance imaging studies, may be used to help screen for a higher level of care in select patients.
Caudal Duplication Of Hind Gut And Lower Genitourinary Tract In A Female Child
Authors: Yadava Dr. V.N.S. , Prasad Dr. Jina Raghwendra , Prasad Dr. Kushwaha Komal
Published: September 2023

Two year old, with congenital anomaly of duplication of hind gut upto sigmoid flexor with one open end and other closed, as well as double bladder and double urethra opening below two clitoris and two vaginal vaults is presented.
Immunoglobulines And Protein Profiles in Burn Patients
Authors: Arora Dr. Anupama , Mehta Dr. Satish K. , Singh Dr. Kartar
Published: September 2023

The Serum immunoglobulins IgG, IgA, and IgM following burns remain subnormal for 7 days and return to normalcy by 14th to 21st day. Infection, infusion of ammino acids or antimicrobial agents used, have little effect.
Serum Protein Levels Following Amniotic Membrane Application in Burns
Authors: Barier Dr. L.M. , Bhat Dr. F.A.
Published: September 2023

Fifty patients in 18 months were subjected to this study. On second and on fifteenth day serum protein levels were studied. Both groups under study gave raised levels. Control group where burn surfaces were treated by antimicrobial cream showed 3% rise and those treated with amniotic membrane gave 11% rise in serum protein levels.
Chlorpromazine And Graft Survival An Experimental Study
Authors: Keswani Dr. N.K. , Misra Dr. Tatsat , Srivastava Dr. D.C. , Bansal Dr. Ajai
Published: September 2023

Large number of drugs have been used to make the longer length of the flap to survive in experimental animals. In present study, chlorpromazine has been used in experimental rats. In all, thirty albino rats were experimented. Longer length treated flap survival rate was observed in chlorpromazine group.
Congenital Midline Nasal Sinus/cyst
Authors: Khan Prof. Masood H. , Bhat Dr. F.A. , Khan Dr. A.H. , Yaseen Dr. M.
Published: September 2023

An unusual presentation of midline nasal sinus associated with dermoid cyst is presented. Two theories of causation are reviewed.
Problem And Principles Of Surgical Treatment Of Haemangiomas
Authors: Prasanna Dr. Mita
Published: September 2023

Surgical excision of haemangiomas in selected cases is the quickest and surest method of cure. However, this treatment modality has never been very popular because of problems of bleedings, recurrence and need for reconstruction later. A study of 25 cases of various types of haemangiomas treated surgically is presented.
Composite Conchal Graft In Failed Rhinoplasty
Authors: Bhiwapurkar Dr. Rajan
Published: September 2023

Rhinoplasty to improve aesthetic appeal is now being carried out in ever larger numbers. Failure rate has also in recent times shown a rise. In best of experienced hands too, Augumentation Rhinoplasty some times fails to achieve desired results due to various reasons. One of them is when alar spring does not maintain its natural shape, producing a pinched nose look. How to correct this by a skin cartalage composite conchal graft is discussed here in this article.
Nonequilibrium warm dense matter investigated with laser–plasma-based XANES down to the femtosecond
Authors: Dorchies F. , Ta Phuoc K. , Lecherbourg L.
Published: September 2023

The use of laser–plasma-based x-ray sources is discussed, with a view to carrying out time-resolved x-ray absorption spectroscopy measurements, down to the femtosecond timescale. A review of recent experiments performed by our team is presented. They concern the study of the nonequilibrium transition of metals from solid to the warm dense regime, which imposes specific constraints (the sample being destroyed after each shot). Particular attention is paid to the description of experimental devices and methodologies. Two main types of x-ray sources are compared, respectively, based on the emission of a hot plasma, and on the betatron radiation from relativistic electrons accelerated by laser.
A solenoid injector based drop-on-demand system for generating large droplets
Authors: Coşar Veli Can , Şen Onur , Ertunç Özgür , Qureshi Sarmad , Bebek Özkan
Published: September 2023

This paper proposes a drop-on-demand (DOD) system that can produce single droplets of highly repeatable size in the order of 2 mm. This system utilizes an on-the-shelf solenoid injector used in automotive applications. The design methodology is explained along with the necessary measurements and numerical simulations of droplet generation. The invention consists of a solenoid injector that produces monodisperse single or in-series droplets with the help of a developed pulse width modulated signal generator. Mass per injection is measured over a range of supply pressures and injection durations to find the operation window to generate 2 mm droplets. Later, various nozzle geometries are designed and tested by flow simulations. The contracting nozzle is found suitable for generating single droplets, so the design is implemented at the tip of the solenoid injector. The effects of different opening times, pressures, and nozzle’s orifice diameters were tested to observe the operating window of the newly designed DOD system and the repeatability of generated droplets by utilizing a coherent circular Hough transform image processing algorithm to measure droplet sizes. The standard deviation of measured diameters is less than 5% of the mean droplet diameter, which is in the range of 1.68–2.07 mm. Next, the voltage and current signals are measured per injection, and exact instants for the initiation and ending for both opening and closing are determined to construct transient mass flow rate functions for flow simulations in which the dependence of droplet formation on the speed of closing is revealed. The numerical and experimental results indicate the repeatability and consistency of the invention.
Synergy of semiempirical models and machine learning in computational chemistry
Authors: Fedik Nikita , Nebgen Benjamin , Lubbers Nicholas , Barros Kipton , Kulichenko Maksim , Li Ying Wai , Zubatyuk Roman , Messerly Richard , Isayev Olexandr , Tretiak Sergei
Published: September 2023

Catalyzed by enormous success in the industrial sector, many research programs have been exploring data-driven, machine learning approaches. Performance can be poor when the model is extrapolated to new regions of chemical space, e.g., new bonding types, new many-body interactions. Another important limitation is the spatial locality assumption in model architecture, and this limitation cannot be overcome with larger or more diverse datasets. The outlined challenges are primarily associated with the lack of electronic structure information in surrogate models such as interatomic potentials. Given the fast development of machine learning and computational chemistry methods, we expect some limitations of surrogate models to be addressed in the near future; nevertheless spatial locality assumption will likely remain a limiting factor for their transferability. Here, we suggest focusing on an equally important effort—design of physics-informed models that leverage the domain knowledge and employ machine learning only as a corrective tool. In the context of material science, we will focus on semi-empirical quantum mechanics, using machine learning to predict corrections to the reduced-order Hamiltonian model parameters. The resulting models are broadly applicable, retain the speed of semiempirical chemistry, and frequently achieve accuracy on par with much more expensive ab initio calculations. These early results indicate that future work, in which machine learning and quantum chemistry methods are developed jointly, may provide the best of all worlds for chemistry applications that demand both high accuracy and high numerical efficiency.
Visibility graph-based segmentation of multivariate time series data and its application
Authors: Hu Jun , Chu Chengbin , Zhu Peican , Yuan Manman
Published: September 2023

In this paper, we propose an efficient segmentation approach in order to divide a multivariate time series through integrating principal component analysis (PCA), visibility graph theory, and community detection algorithm. Based on structural characteristics, we can automatically divide the high-dimensional time series into several stages. First, we adopt the PCA to reduce the dimensions; thus, a low dimensional time series can be obtained. Hence, we can overcome the curse of dimensionality conduct, which is incurred by multidimensional time sequences. Later, the visibility graph theory is applied to handle these multivariate time series, and corresponding networks can be derived accordingly. Then, we propose a community detection algorithm (the obtained communities correspond to the desired segmentation), while modularity Q is adopted as an objective function to find the optimal. As indicated, the segmentation determined by our method is of high accuracy. Compared with the state-of-art models, we find that our proposed model is of a lower time complexity (O(n3)), while the performance of segmentation is much better. At last, we not only applied this model to generated data with known multiple phases but also applied it to a real dataset of oil futures. In both cases, we obtained excellent segmentation results.
Unveiling the magnetic structure and phase transition of Cr2CoAl using neutron diffraction
Authors: Dutt Gupt Guru , Kareri Yousef , Hester James , Ulrich Clemens , Dhaka R. S.
Published: September 2023

We report the detailed analysis of temperature dependent neutron diffraction pattern of the Cr2CoAl inverse Heusler alloy and unveil the magnetic structure up to the phase transition as well as its fully compensated ferrimagnetic nature. The Rietveld refinement of the diffraction pattern using the space group I4¯m2 confirms the inverse tetragonal structure over the large temperature range from 100 to 900 K. The refinement of the magnetic phase considering the wave vector k= (0, 0, 0) reveals the ferrimagnetic nature of the sample below 730±5 K. This transition temperature is obtained from empirical power law fitting of the variation in the ordered net magnetic moment variation in intensity of (110) peak as a function of temperature. The spin configuration of the microscopic magnetic structure suggests the nearly fully compensated ferrimagnetic behavior where the magnetic moments of Cr2 are antiparallel with respect to the Cr1 and Co moments. Moreover, the observed anomaly in the thermal expansion and lattice parameters at 730±5 K suggests that the distortion in the crystal structure may play an important role in the magnetic phase transition.
Order parameter dynamics in Mn3Sn driven by DC and pulsed spin–orbit torques
Authors: Shukla Ankit , Qian Siyuan , Rakheja Shaloo
Published: September 2023

We numerically investigate and develop analytic models for both the DC and pulsed spin–orbit-torque (SOT)-driven response of order parameter in single-domain Mn3Sn, which is a metallic antiferromagnet with an anti-chiral 120° spin structure. We show that DC currents above a critical threshold can excite oscillatory dynamics of the order parameter in the gigahertz to terahertz frequency spectrum. Detailed models of the oscillation frequency vs input current are developed and found to be in excellent agreement with the numerical simulations of the dynamics. In the case of pulsed excitation, the magnetization can be switched from one stable state to any of the other five stable states in the Kagome plane by tuning the duration or the amplitude of the current pulse. Precise functional forms of the final switched state vs the input current are derived, offering crucial insights into the switching dynamics of Mn3Sn. The readout of the magnetic state can be carried out via either the anomalous Hall effect or the recently demonstrated tunneling magnetoresistance in an all-Mn3Sn junction. We also discuss possible disturbance of the magnetic order due to heating that may occur if the sample is subject to large currents. Operating the device in a pulsed mode or using low DC currents reduces the peak temperature rise in the sample due to Joule heating. Our predictive modeling and simulation results can be used by both theorists and experimentalists to explore the interplay of SOT and the order dynamics in Mn3Sn and to further benchmark the device performance.
Laser-based remote detection of leaf wetness
Authors: Gaetani R. , Feugier F. G. , Masenelli B.
Published: September 2023

Pesticide-free agricultural strategies need new tools for disease prevention. Better than early detection of disease, detection of conditions favorable to their appearance can be a progress. In the case of fungal diseases, the presence of water on the plant surface is necessary. In order to detect remotely this presence early and at the scale of a crop field, we propose a low-cost solution based on laser reflection. Here, experimental results in a controlled environment are presented on both hydrophobic and hydrophilic leaves (rapeseed Brassica Napus and grapevine Vitis Vinifera, respectively). We first assess the water detection on a leaf surface by recreating the dew formation process. We next evaluate the influence of the scanning measurement and leaf inclination on the detection to get closer to in-field conditions. Results show that this method is very sensitive on both types of leaves. Water detection is possible from a low surface coverage with a high temporal precision at 1 m. In the hydrophobic case, water on a leaf surface leads to an increase of the detected signal up to three times compared to a dry leaf. The corresponding minimum surface coverage detectable at 1 m is evaluated at 1.6% thanks to 2D ray-tracing numerical simulations. In the hydrophilic case, on the contrary, water on a leaf surface leads to a decrease of the detected signal by almost half. For both types, the dew detection delay is contained under 5 min and can be improved. Finally, the presented results pave the way to a field application.
Sub-quarter micrometer periodically poled Al0.68Sc0.32N for ultra-wideband photonics and acoustic devices
Authors: Tang Zichen , Esteves Giovanni , Olsson Roy H.
Published: September 2023

In this study, we demonstrate the ability of polarity inversion of sputtered aluminum scandium nitride thin films through post-fabrication processes with domain widths as small as 220 nm at a periodicity of 440 nm. An approach using photo- and electron-beam lithography to generate sub-quarter micrometer feature size with adjustable duty cycle through a lift-off process is presented. The film with a coercive field Ec+ of 5.35 MV/cm was exercised first with a 1 kHz triangular double bipolar wave and ultimately poled with a 0.5 kHz double monopolar wave using a Radiant Precision Premier II tester. The metal polar (M-polar) and nitrogen polar (N-polar) domains were identified and characterized through potassium hydroxide wet etching as well as piezoresponse force microscopy (PFM). Well-distinguished boundaries between the oppositely polarized domain regions were confirmed through the phase diagram of the PFM results. The relationship between the electrode width, poling voltage, and domain growth was experimentally studied and statistically analyzed, where 7.96 nm/V domain width broadening vs escalating poling voltage was observed. This method produces extremely high domain spatial resolution in III-nitride materials via poling and is transferable to a CMOS-compatible photolithography process. The spatial resolution of the periodically poled Al0.68Sc0.32N is suitable for second-harmonic generation of deep ultraviolet through quasi-phase-matching and RF MEMS operating in the X-Band spectrum.
Critical behavior in a chiral molecular model
Authors: Piaggi Pablo M. , Car Roberto , Stillinger Frank H. , Debenedetti Pablo G.
Published: September 2023

Understanding the condensed-phase behavior of chiral molecules is important in biology as well as in a range of technological applications, such as the manufacture of pharmaceuticals. Here, we use molecular dynamics simulations to study a chiral four-site molecular model that exhibits a second-order symmetry-breaking phase transition from a supercritical racemic liquid into subcritical D-rich and L-rich liquids. We determine the infinite-size critical temperature using the fourth-order Binder cumulant, and we show that the finite-size scaling behavior of the order parameter is compatible with the 3D Ising universality class. We also study the spontaneous D-rich to L-rich transition at a slightly subcritical temperature of T = 0.985Tc, and our findings indicate that the free energy barrier for this transformation increases with system size as N2/3, where N is the number of molecules, consistent with a surface-dominated phenomenon. The critical behavior observed herein suggests a mechanism for chirality selection in which a liquid of chiral molecules spontaneously forms a phase enriched in one of the two enantiomers as the temperature is lowered below the critical point. Furthermore, the increasing free energy barrier with system size indicates that fluctuations between the L-rich and D-rich phases are suppressed as the size of the system increases, trapping it in one of the two enantiomerically enriched phases. Such a process could provide the basis for an alternative explanation for the origin of biological homochirality. We also conjecture the possibility of observing nucleation at subcritical temperatures under the action of a suitable chiral external field.
MoSe2 nanosheet as a lung cancer biosensor: A DFT study
Authors: Mosahebfard Ali , Moaddeli Mohammad
Published: September 2023

Early cancer diagnosis strongly relies on finding appropriate materials for the detection of respected biomarkers. For the first time, we have theoretically investigated the capability of the MoSe2 monolayer to detect three lung cancer biomarkers, including hexanal, nonanal, and p-cresol. To this end, adsorption performance, bandgap alteration, and charge transfer of the MoSe2 monolayer upon exposure to the three biomarkers were studied using density functional theory. The results, in all cases, indicate that the charge transfer is from the monolayer to the adsorbed biomarkers, and the adsorption of biomarkers decreases the bandgap of the monolayer, approving the p-type sensing character of the MoSe2 monolayer. This is in complete agreement with the band structure analysis of the material and the previous reports in the literature. Our findings demonstrated the appropriate performance of the MoSe2 monolayer in terms of the physisorption of the lung cancer biomarkers and desirable recovery times in the desorption process. Further performance enhancement of MoSe2 as a lung cancer biosensor can be the subject of future studies.
High-resolution reconstruction of spectrum-overlapped off-axis holography by deflecting reference beam of Gaussian symmetry
Authors: Chen Benyong , Zhang Jifan , Huang Liu , Yan Liping
Published: September 2023

In digital holography, extracting the +1-order spectrum accurately and making full utilization of the spatial bandwidth of the CCD sensor are essential for high-resolution and artifacts-free quantitative phase imaging. In this paper, using the light intensity symmetry of the Gaussian laser beam, we delicately eliminate the zero-order spectrum by means of subtraction of two off-axis hologram spectra acquired by symmetrically deflecting the reference beam. Therefore, the +1-order spectrum can be extracted accurately even if it is completely overlapped with the zero-order spectrum. Compared with phase-shifting methods, such as pi-phase and random phase, which require accurate control or calculation of the phase-shifting amount, this proposed method does not need to precisely control the deflection angle of reference beam. Being achievable the maximum utilization of half-space bandwidth of the CCD sensor, the proposed method has realized high-resolution imaging demonstrated by the experimental results of three specimens. This method has general applications in digital holography, such as eliminating the zero-order spectrum and extracting the +1-order spectrum.
Toward a structural identification of metastable molecular conformations
Authors: Lemcke Simon , Appeldorn Jörn H. , Wand Michael , Speck Thomas
Published: September 2023

Interpreting high-dimensional data from molecular dynamics simulations is a persistent challenge. In this paper, we show that for a small peptide, deca-alanine, metastable states can be identified through a neural net based on structural information alone. While processing molecular dynamics data, dimensionality reduction is a necessary step that projects high-dimensional data onto a low-dimensional representation that, ideally, captures the conformational changes in the underlying data. Conventional methods make use of the temporal information contained in trajectories generated through integrating the equations of motion, which forgoes more efficient sampling schemes. We demonstrate that EncoderMap, an autoencoder architecture with an additional distance metric, can find a suitable low-dimensional representation to identify long-lived molecular conformations using exclusively structural information. For deca-alanine, which exhibits several helix-forming pathways, we show that this approach allows us to combine simulations with different biasing forces and yields representations comparable in quality to other established methods. Our results contribute to computational strategies for the rapid automatic exploration of the configuration space of peptides and proteins.
Dynamic transformation of bio-inspired single-chain nanoparticles at interfaces
Authors: Hilburg Shayna L. , Jin Tianyi , Alexander-Katz Alfredo
Published: September 2023

The interfacial behavior of macromolecules dictates their intermolecular interactions, which can impact the processing and application of polymers for pharmaceutical and synthetic use. Using molecular dynamics simulations, we observe the evolution of a random heteropolymer in the presence of liquid–liquid interfaces. The system of interest forms single-chain nanoparticles through hydrophobic collapse in water, lacking permanent crosslinks and making their morphology mutable in new environments. Complex amphiphilic polymers are shown to be capable of stabilizing high interfacial tension water–hexane interfaces, often unfolding to maximize surface coverage. Despite drastic changes to polymer conformation, monomer presence in the water phase is generally maintained and most changes are due to increased hydrophobic solvent exposure toward the oil phase. These results are then compared to the behavior at the water–graphene interface, where the macromolecules adsorb but do not remodel. The polymer’s behavior is shown to depend significantly on both its own amphiphilic character and the deformability of the interface.
Experimental investigation into the thermal performance of a solar steam generator based on spray cooling heat transfer and porous silicon carbide ceramic
Authors: Wang Hongjun , Zhang Qiangqiang , Li Xin , Zhang Xia , Ma Tianzeng
Published: September 2023

A solid oxide electrolysis cell require high-temperature steam. However, using electricity to generate steam is highly energy intensive, and concentrated solar power is a good substitute for it. The authors of this study propose a solar steam generator with an enhanced capacity for heat transfer by installing a porous ceramic material inside it and using spray cooling technology. Currently used steam generators produce steam at a temperature that rarely reaches 700–1000 °C. The steam generator developed here can produce steam at a temperature of up to 800 °C by using concentrated solar power. Moreover, we tested two porous silicon carbide ceramic materials for use in the generator under various experimental conditions and investigated the effects of the irradiation power, rate of flow at the inlet, and porosity of the ceramic material (ranging from 70% to 85%) on its thermal performance. The results showed that the temperature at the outlets of steam generators equipped with the two kinds of ceramic materials increased as the irradiation power was increased from 2.3 to 4.6 kW, and their thermal efficiency increased from 17% to 65.5% as the rate of flow of water at the inlet was raised from 0.92 to 4.68 L/h. The thermal efficiency of the generator equipped with the ceramic with a low porosity (70%) was approximately 26% greater than that of the generator equipped with the ceramic with a high porosity (85%) at an irradiation power of 4.2 kW. When the solar simulator was suddenly turned off, the generator with the lower porosity was more resistant to interference. The results here provide an important reference for optimizing the steam generator.
Negative Hall coefficient in band conduction region in heavily Al-doped 4H-SiC
Authors: Matsuura Hideharu , Hidaka Atsuki , Ji Shiyang , Eto Kazuma , Ishida Yuuki , Yoshida Sadafumi
Published: September 2023

At low temperatures, the Hall coefficients in heavily Al-doped 4H-SiC are reported to be negative in the band conduction region as well as in the hopping conduction regions (i.e., nearest-neighbor hopping conduction region and variable-range hopping conduction region). A physical model was proposed to explain the negative sign of RH(T) in the hopping conduction regions. However, the negative value of RH(T) in the conduction band region remains unexplained. This study proposed a physical model to explain the negative value of RH(T) in the conduction band region. In addition to the valence band, doping copious amounts of Al acceptors in 4H-SiC causes a strong overlap of the wave functions of the excited states of Al acceptors, which results in the formation of allowed bands, referred to as allowed minibands. Although the holes can flow freely through the valence band as well as the allowed minibands, the energy–momentum relationship in the valence band and the allowed minibands determines the sign of RH(T). As elucidated here, if the holes flow primarily in the lower parts of the allowed minibands, the RH(T) in the band conduction region becomes negative, whereas if the holes flow primarily in the upper parts of the allowed minibands and the valence band, the RH(T) becomes positive.
A model for multiphase flow velocity calculation in pipelines based on ultrasonic sensors
Authors: Liang Haibo , Song Chuanhao , Wang Ren , Yang Hai
Published: September 2023

In the petroleum and natural gas industry, a wide variety of multiphase fluids are prevalent, and precise measurement of their flow velocity in pipelines holds significant importance for different stages of well drilling and construction. However, due to the presence of large solid particles and the corrosive nature of the liquid phase in multiphase fluids within the petroleum industry, invasive measurement methods struggle to maintain long-term acceptable detection accuracy. Therefore, the non-contact fluid flow velocity measurement method based on ultrasonic sensors exhibits substantial research value. Nonetheless, when employing this approach for pipeline multiphase fluid flow velocity measurement, the abundance of background interference noise at the site poses challenges in Doppler echo signal reconstruction and results in lower precision for frequency shift extraction, leading to considerable errors in flow velocity calculation results. To address this issue, the present study utilizes a transmit-receive separated continuous wave ultrasonic sensor. First, a mathematical model is developed for the superimposed signal of ultrasonic Doppler echoes within the pipeline. Next, a novel signal reconstruction method is proposed by employing Chebyshev polynomials for interpolation computation of the sampled discrete signals. Subsequently, a Doppler shift model is introduced, leading to the formulation of a new model for multiphase flow velocity calculation in pipelines based on ultrasonic sensors. Finally, a comparison experiment for full-pipe multiphase flow velocity detection is conducted to validate the computational performance of the new model. The experimental results show that, compared with the FFT model and the conventional cross correlation model, the comprehensive meter factor of the ultrasonic flow measurement system with the new model is reduced by 0.024 445, the accuracy is reduced by 2.98%, the nonlinear error is reduced by 2.4405%, the average relative error is reduced by 0.646%, the standard deviation is reduced by 0.045 175, and the root mean squared error is reduced by 0.029 615.
A numerical-tensorial “hybrid” nuclear motion Hamiltonian and dipole moment operator for spectra calculation of polyatomic nonrigid molecules
Authors: Rey Michaël , Viglaska Dominika , Egorov Oleg , Nikitin Andrei V.
Published: September 2023

The analysis and modeling of high-resolution spectra of nonrigid molecules require a specific Hamiltonian and group-theoretical formulation that differs significantly from that of more familiar rigid systems. Within the framework of Hougen–Bunker–Johns (HBJ) theory, this paper is devoted to the construction of a nonrigid Hamiltonian based on a suitable combination of numerical calculations for the nonrigid part in conjunction with the irreducible tensor operator method for the rigid part. For the first time, a variational calculation from ab initio potential energy surfaces is performed using the HBJ kinetic energy operator built from vibrational, large-amplitude motion, and rotational tensor operators expressed in terms of curvilinear and normal coordinates. Group theory for nonrigid molecules plays a central role in the characterization of the overall tunneling splittings and is discussed in the present approach. The construction of the dipole moment operator is also examined. Validation tests consisting of a careful convergence study of the energy levels as well as a comparison of results obtained from independent computer codes are given for the nonrigid molecules CH2, CH3, NH3, and H2O2. This work paves the way for the modeling of high-resolution spectra of larger nonrigid systems.
Optoelectronic bio-synaptic plasticity on neotype kesterite memristor with switching ratio >104
Authors: Yang Fengxia , Wei Wenbin , Dong Xiaofei , Zhao Yun , Chen Jiangtao , Chen Jianbiao , Zhang Xuqiang , Li Yan
Published: September 2023

Optoelectronic memristors hold the most potential for realizing next-generation neuromorphic computation; however, memristive devices that can integrate excellent resistive switching and both electrical-/light-induced bio-synaptic behaviors are still challenging to develop. In this study, an artificial optoelectronic synapse is proposed and realized using a kesterite-based memristor with Cu2ZnSn(S,Se)4 (CZTSSe) as the switching material and Mo/Ag as the back/top electrode. Benefiting from unique electrical features and a bi-layered structure of CZTSSe, the memristor exhibits highly stable nonvolatile resistive switching with excellent spatial uniformity, concentrated Set/Reset voltage distribution (variation <0.08/0.02 V), high On/Off ratio (>104), and long retention time (>104 s). A possible mechanism of the switching behavior in such a device is proposed. Furthermore, these memristors successfully achieve essential bio-synaptic functions under both electrical and various visible light (470–655 nm) stimulations, including electrical-induced excitatory postsynaptic current, paired pulse facilitation, long-term potentiation, long-term depression, spike-timing-dependent plasticity, as well as light-stimulated short-/long-term plasticity and learning-forgetting-relearning process. As such, the proposed neotype kesterite-based memristor demonstrates significant potential in facilitating artificial optoelectronic synapses and enabling neuromorphic computation.
Thermodynamics of imbibition in capillaries of double conical structures—hourglass, diamond, and sawtooth shaped capillaries
Authors: Iwamatsu Masao
Published: September 2023

Thermodynamics of imbibition (intrusion and extrusion) in capillaries of double conical structures is theoretically studied using the classical capillary model. By extending the knowledge of the thermodynamics of a single conical capillary, not only the nature of spontaneous imbibition but that of forced imbibition under applied external pressure are clarified. Spontaneous imbibition in capillaries of double conical structure can be predicted from the Laplace pressure in a single conical capillary. To understand the forced imbibition process, the free energy landscape along the imbibition pathway is calculated. This landscape shows either a maximum or a minimum. The former acts as the energy barrier, and the latter acts as the trap for the liquid–vapor meniscus so that the imbibition process can be either abrupt with a pressure hysteresis or gradual and continuous. The landscape also predicts a completely filled, a half-filled, and a completely empty state as the thermodynamically stable state. Furthermore, it also predicts a completely filled and a half-filled state of metastable liquid, which can be prepared by the combination of the intrusion and the extrusion process. Our study could be useful for understanding various natural fluidic systems and for designing functional fluidic devices such as a diode and a switch.
Protein array processing software for automated semiquantitative analysis of serum antibody repertoires
Authors: Yadav Ajeet Singh , Ooi Chin Hong , An Hongjie , Nguyen Nam-Trung , Kijanka Gregor S.
Published: September 2023

Effective immunotherapies activate natural antitumor immune responses in patients undergoing treatment. The ability to monitor immune activation in response to immunotherapy is critical in measuring treatment efficacy over time and across patient cohorts. Protein arrays are systematically arranged, large collections of annotated proteins on planar surfaces, which can be used for the characterization of disease-specific and treatment-induced antibody repertoires in individuals undergoing immunotherapy. However, the absence of appropriate image analysis and data processing software presents a substantial hurdle, limiting the uptake of this approach in immunotherapy research. We developed a first, automated semiquantitative open-source software package for the analysis of widely used protein macroarrays. The software allows accurate single array and inter-array comparative studies through the tackling of intra-array inconsistencies arising from experimental disparities. The innovative and automated image analysis process includes adaptive positioning, background identification and subtraction, removal of null signals, robust statistical analysis, and protein pair validation. The normalized values allow a convenient semiquantitative data analysis of different samples or timepoints. Enabling accurate characterization of sample series to identify disease-specific immune profiles or their relative changes in response to treatment may serve as a diagnostic or predictive tool of disease.
Wide-field quantitative magnetic imaging of superconducting vortices using perfectly aligned quantum sensors
Authors: Nishimura Shunsuke , Kobayashi Taku , Sasaki Daichi , Tsuji Takeyuki , Iwasaki Takayuki , Hatano Mutsuko , Sasaki Kento , Kobayashi Kensuke
Published: September 2023

Various techniques have been applied to visualize superconducting vortices, providing clues to their electromagnetic response. Here, we present a wide-field, quantitative imaging of the stray field of the vortices in a superconducting thin film using perfectly aligned diamond quantum sensors. Our analysis, which mitigates the influence of the sensor inhomogeneities, visualizes the magnetic flux of single vortices in YBa2Cu3O7−δ with an accuracy of ±10%. The obtained vortex shape is consistent with the theoretical model, and penetration depth and its temperature dependence agree with previous studies, proving our technique's accuracy and broad applicability. This wide-field imaging, which in principle works even under extreme conditions, allows the characterization of various superconductors.
Probing exciton dynamics with spectral selectivity through the use of quantum entangled photons
Authors: Fujihashi Yuta , Miwa Kuniyuki , Higashi Masahiro , Ishizaki Akihito
Published: September 2023

Quantum light is increasingly recognized as a promising resource for developing optical measurement techniques. Particular attention has been paid to enhancing the precision of the measurements beyond classical techniques by using nonclassical correlations between quantum entangled photons. Recent advances in the quantum optics technology have made it possible to manipulate spectral and temporal properties of entangled photons, and photon correlations can facilitate the extraction of matter information with relatively simple optical systems compared to conventional schemes. In these respects, the applications of entangled photons to time-resolved spectroscopy can open new avenues for unambiguously extracting information on dynamical processes in complex molecular and materials systems. Here, we propose time-resolved spectroscopy in which specific signal contributions are selectively enhanced by harnessing nonclassical correlations of entangled photons. The entanglement time characterizes the mutual delay between an entangled twin and determines the spectral distribution of photon correlations. The entanglement time plays a dual role as the knob for controlling the accessible time region of dynamical processes and the degrees of spectral selectivity. In this sense, the role of the entanglement time is substantially equivalent to the temporal width of the classical laser pulse. The results demonstrate that the application of quantum entangled photons to time-resolved spectroscopy leads to monitoring dynamical processes in complex molecular and materials systems by selectively extracting desired signal contributions from congested spectra. We anticipate that more elaborately engineered photon states would broaden the availability of quantum light spectroscopy.
Interaction of methanol with molecular hydrogen: Ab initio potential energy surface and scattering calculations
Authors: Dagdigian Paul J.
Published: September 2023

The potential energy surface (PES) describing the interaction of the methanol molecule with molecular hydrogen has been calculated by the use of the explicitly correlated coupled cluster method, including single, double, and (perturbative) triple excitations [CCSD(T)-F12a] and a correlation-consistent aug-cc-pVTZ basis, with the assumption of fixed molecular geometries. The computed points were fit to a functional form appropriate for time-independent quantum scattering calculations of rotationally inelastic cross sections and rate coefficients. Stationary points on the PES were located, and the global minimum was found to have an energy equal to −254.7 cm−1 relative to the energy of the separated molecules. This PES was used in time-independent close coupling quantum scattering calculations to determine state-to-state cross sections and rate coefficients for rotational transitions within the A- and E-type nuclear spin torsional ground states.
Communicating medical information with Aboriginal patients: lessons learned from GPs and GP registrars in Aboriginal primary health care
Authors: Ghamrawi Wissam , Benson Jill , Kennedy Emma
Published: September 2023

Background Aboriginal culture stands as the oldest continuous culture in the world. It gives paramount importance to a harmonious balance between personal connections to the body, spirit, and mind, as well as collective relationships with family, land, and community, integral to the wellbeing of Aboriginal people. However, obstacles can emerge for patients due to language barriers, cultural differences, or a historical lack of trust in the healthcare system. The establishment of Aboriginal Community Controlled Health Organisations (ACCHOs) has undoubtedly improved the healthcare experience for Aboriginal patients, yet there is limited research on the specific approaches utilised by general practitioners (GPs) working in these clinics. Methods Twelve semi-structured interviews were conducted with two groups of GPs working in Aboriginal health. Each GP was presented with three scenarios and asked questions related to each scenario. Braun and Clarke’s method of thematic analysis was applied to transcribed interviews. Results Patient-doctor relationship, health literacy, and engagement with the health system emerged as key factors influencing communication with Aboriginal patients. Experienced GPs, despite differing clinical backgrounds, shared concise yet similar ideas to their less experienced counterparts. Notably, experienced GPs prioritised non-medical conversations and mindful body language, emphasising the importance of building strong patient relationships over other consultation aspects. Conclusions This research provides initial insights for GPs in Aboriginal health, comparing experienced GPs with more than 10 years experience to novices. However, further research involving Aboriginal patients is needed to validate GP strategies and understand their significance from the patients’ perspective.
The physics of time
Authors: Wang Renqiang , Li Heng , Yang Bo
Published: September 2023

According to the Temporal Focus Hypothesis, people’s orientations of sagittal spatiotemporal mappings are conditioned by their characteristic patterns of attention to the past and/or future. While a growing body of research has investigated how a variety of psychological, social, and environmental factors associated with temporal focus shape implicit space-time mappings, little is known about whether the degree of entropy in the visual context influences spatial conceptions of time. Based on the findings that high-entropy images invoke a past-focused mindset and low-entropy images invoke a future-focused mindset, the current work explores how entropy impacts people’s temporal focus and mental representations of time. In Study 1 involving a self-report measure of temporal focus, we found that while high-entropy images increased Chinese students’ attention to the past and led to more past-in-front responses, low-entropy images increased Chinese students’ attention to the future and led to more future-in-front responses. Using both self-reported measures and other-report ratings of temporal focus, Study 2 conceptually replicated the findings of Study 1 in a more diverse population. Considered together, these results bolster support for the Temporal Focus Hypothesis that entropy triggers corresponding changes in temporal focus and in mental sagittal space-time mappings.
Search for postmerger gravitational waves from binary neutron star mergers using a matched-filtering statistic
Authors: Królak Andrzej , Jaranowski Piotr , Bejger Michał , Ciecieląg Paweł , Dorosh Orest , Pisarski Andrzej
Published: September 2023

In this paper, we present a new method to search for a short, a few tens of millis long, postmerger gravitational-wave (GW) signal following the merger of two neutron stars. Such a signal could follow the event GW170817 observed by Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo detectors. Our method is based on a matched filtering statistic and an approximate template of the postmerger signal in the form of a damped sinusoid. We test and validate our method using postmerger numerical simulations from the CoRe database. We find no evidence of the short postmerger signal in the LIGO data following the GW170817 event and we obtain upper limits. For short postmerger signals investigated, our best upper limit on the root sum square of the GW strain emitted from 1.15 kHz to 4 kHz is

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at 50% detection efficiency. The distance corresponding to this best upper limit is 4.64 Mpc.