bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stable accretion and episodic outflows in the young transition disk system GM Aurigae
Authors: Bouvier J. , Sousa A. , Pouilly K. , Almenara J. M. , Donati J.-F. , Alencar S. H. P. , Frasca A. , Grankin K. , Carmona A. , Pantolmos G. , Zaire B. , Bonfils X. , Bayo A. , Rebull L. M. , Alonso-Santiago J. , Gameiro J. F. , Cook N. J. , Artigau E. 
Published: January 2023

Context. Young stellar systems actively accrete from their circumstellar disk and simultaneously launch outflows. The physical link between accretion and ejection processes remains to be fully understood.
Aims. We investigate the structure and dynamics of magnetospheric accretion and associated outflows on a scale smaller than 0.1 au around the young transitional disk system GM Aur.
Methods. We devised a coordinated observing campaign to monitor the variability of the system on timescales ranging from days to months, including partly simultaneous high-resolution optical and near-infrared spectroscopy, multiwavelength photometry, and low-resolution near-infrared spectroscopy, over a total duration of six months, covering 30 rotational cycles. We analyzed the photometric and line profile variability to characterize the accretion and ejection processes.
Results. The optical and near-infrared light curves indicate that the luminosity of the system is modulated by surface spots at the stellar rotation period of 6.04 ± 0.15 days. Part of the Balmer, Paschen, and Brackett hydrogen line profiles as well as the HeI 5876 Å and HeI 10830 Å line profiles are modulated on the same period. The Paβ line flux correlates with the photometric excess in the u′ band, which suggests that most of the line emission originates from the accretion process. High-velocity redshifted absorptions reaching below the continuum periodically appear in the near-infrared line profiles at the rotational phase in which the veiling and line fluxes are the largest. These are signatures of a stable accretion funnel flow and associated accretion shock at the stellar surface. This large-scale magnetospheric accretion structure appears fairly stable over at least 15 and possibly up to 30 rotational periods. In contrast, outflow signatures randomly appear as blueshifted absorption components in the Balmer and HeI 10830 Å line profiles. They are not rotationally modulated and disappear on a timescale of a few days. The coexistence of a stable, large-scale accretion pattern and episodic outflows supports magnetospheric ejections as the main process occurring at the star-disk interface.
Conclusions. Long-term monitoring of the variability of the GM Aur transitional disk system provides clues to the accretion and ejection structure and dynamics close to the star. Stable magnetospheric accretion and episodic outflows appear to be physically linked on a scale of a few stellar radii in this system.
Laboratory modeling in laser-induced plasma to estimate the pressure in bolide wake
Authors: Zakuskin A. S. , Beglaryan B. G. , Labutin T. A. 
Published: January 2023

Aims. We study Fe and FeO emission in laser-induced plasma under reduced pressure to develop an approach for finding the conditions under which the laboratory plasma state matches the state of bolide wake plasma.
Methods. To acquire spectra of laser-induced plasma, we ablated a target of Fe3O4 in a vacuum chamber using a Q-switched laser. The Boltzmann plot method and Stark broadening of the emission lines were used to estimate the plasma temperature and electron number density. The intensity ratios of two Fe I lines (544.61 nm and 558.69 nm) to the intensity of FeO orange band at 587.1 nm were calculated to compare the conditions in laser-induced plasma and bolide wake plasma.
Results. Several combinations of pressure (75–150 Torr) and delay (12–15 μs) lead to the highest degree of similarity between laser-induced plasma and the Beneov bolide spectra at an altitude of 39 km. Importantly, the plasma parameters and pressure are consistent at these points. A detailed comparison of the spectra shows that the best-match conditions are 100 Torr and 15 μs. This pressure is ≈25 times higher than the ambient pressure at this altitude.
Conclusions. We assume that the pressure in the bolide wake is higher than the ambient pressure by a factor of 20–30. This can be considered to be the upper bound estimate of the pressure in the bolide wake, and the developed approach would be beneficial to support the modeling of a meteoroid entry.
Coagulase-Negative Staphylococci in Neonatal Blood: How Concerning?
Authors: Ansari Farheen , Banerjee Tuhina , Kumar Ashok , Anupurba Shampa 
Published: January 2023

Abstract
Objective Coagulase-negative staphylococci (CoNS) are being implicated as one of the leading causes of bloodstream infection (BSI). To study the spectrum, prevalence, and antimicrobial susceptibility of CoNS causing BSI in neonates.
Materials and Methods A cross-sectional study was done in level III neonatal intensive care unit (NICU). Blood samples in automated culture bottles were processed as per the standard technique. Previously validated methods were followed for the characterization of CoNS and for AST of standard antibiotics by Kirby Bauer disk diffusion and vancomycin by agar dilution. The prevalence of causative organisms and susceptibility of CoNS were statistically analyzed. Categorical variables were compared by chi-square or Fisher's exact probability tests.
Result In total, 1,365 blood samples (1,365 neonates) were studied, of which 383 (28.05%) were positive and 982 (71.94%) were negative. Gram-positive organisms (GPC) predominated (n = 238; 62.14%) (p < 0.001) with 41.77% (160/383) S. aureus and 13.83% (53/383) CoNS. CoNS included S. epidermidis (19, 38%), S. haemolyticus (7, 14%), S. hominis (6, 12%), S. simulans (6,12%), S. capitis (5,10%), S. cohnii (4, 8%), S. warneri (1, 2%), and S. xylosus (1, 2%). The susceptibility to netilmicin, linezolid, and vancomycin was 100% (p ≤ 0.001), and 54% (n = 27) had vancomycin MIC of 0.125 μg/mL but methicillin-resistant CoNS (MRCoNS) was 70%. Methicillin-susceptible (MS) CoNS had lower MIC of vancomycin (p < 0.05) than MRCoNS.
Conclusion The spectrum of pathogens causing BSI in neonates is changing with predominance of GPC and among CoNS, S. epidermidis. Considerable proportion of MRCoNS with the emergence of MIC creep for vancomycin requires immediate attention.
Salivary IgA as a Surrogate Biomarker for Microbial Infections in Postoperative Patients Receiving Chemo-Radio-Therapy for Head and Neck Cancer
Authors: Chavan Preeti , Bhat Vivek , Joshi Amit , Gupta Tejpal , Murthy Vedang , Noronha Vanita , Rathish Divya , Prabhash Kumar 
Published: January 2023

Abstract
Objective Radiotherapy (RT) and chemotherapy (CT) are important treatment options in patients with head and neck cancers. A common complication of this is microbial colonization or infection of mucosal surfaces. These infections may commonly be due to bacteria or yeasts. Salivary proteins with their buffering activity and immunoglobulin, especially immunoglobulin A (IgA), protect oral tissue, mucosal surfaces, and teeth from various microorganisms. This study characterizes the common microorganisms encountered and evaluates the role of salivary IgA in predicting microbial infections in this group of patients with mucositis.
Methods A total of 150 adult head and neck cancer patients on CTRT were evaluated at baseline and at the end of 3 and 6 weeks, respectively. Oral swabs collected from buccal mucosa were processed in the microbiology laboratory for the presence of microorganisms. Saliva was processed for IgA level estimation on Siemens Dimension Automated biochemistry analyzer.
Results Pseudomonas aeruginosa and Klebsiella pneumoniae were the most common organisms found in our patients, followed by Escherichia coli and group A beta-hemolytic Streptococci. A significant increase (p = 0.0203) in the incidence of bacterial infection was observed in post-CTRT patients (61%) compared to pre-CTRT patients (49.33%). There was significant increase in levels of salivary IgA (p = 0.003) in patients with bacterial and fungal infection (n = 135/267) when compared to those in samples showing no growth (n = 66/183).
Conclusion A significant increase in the incidence of bacterial infection in post-CTRT patients was observed in this study. This study also indicated that postoperative head and neck cancer patients with oral mucositis that developed an infection were associated with high salivary IgA levels, and it may serve as a surrogate biomarker of infection in these patients.
Performance Evaluation of Different RT-PCR Kits for the Direct Detection of SARS-CoV-2 in Preheated Specimens
Authors: Jain Rajeev Kumar , Perumal Nagaraj , Chaurasia Deepti , Shrivastava Rakesh , Ahirwar Kamlesh Kumar , Sharma Archa , Kapoor Garima , Lalwani Jaya 
Published: January 2023

Abstract
Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has created high demand for molecular kits and consumables for mass screening of suspected individuals. Direct real-time polymerase chain reaction (RT-PCR) assay without nucleic acid extraction has several advantages in saving testing time and cost and helps in the rapid reporting of SARS-CoV-2. The present study evaluated the analytical performance of four SARS-CoV-2 RT-PCR for direct RT-PCR testing using preheated specimens.
Methods A total of 100 clinical specimens were selected and divided into three different groups: (1) group I: 20 SARS-CoV-2 positive specimens with high viral load, viz., low Ct values (< 30 Ct), (2) group II: 50 SARS-CoV-2 positive specimens with low viral load, viz., high Ct values (> 30 Ct), and (3) group III: 30 SARS-CoV-2 negative specimens. Specimens were heat-inactivated at 70°C for 10 minutes and cooled down at 4°C and were evaluated for standard and direct RT-PCR method by using ViralDtect-II Multiplex Real-Time PCR kit, TaqPath COVID-19 Combo kit, COVIDsure Pro Multiplex RT-PCR kit, and Hi-PCR Coronavirus (COVID-19) Multiplex Probe PCR kit.
Results Results showed that except ViralDtect-II kit, the other three TaqPath COVID-19 Combo kit, COVIDsure Pro kit, and Hi-PCR Coronavirus (COVID-19) RT-PCR kit were able to amplify all the SARS-CoV-2 genes in the direct RT-PCR method using preheated specimens. In group I specimens, 100% sensitivity was observed in all three RT-PCR kits. In group II specimens, COVIDsure Pro kit was found to be superior among other kits.
Conclusion Direct RT-PCR method during pandemic situation is valuable and cost effective for the detection of SARS-CoV-2. All three TaqPath COVID-19 Combo kit, COVIDsure Pro kit, and Hi-PCR Coronavirus (COVID-19) RT-PCR kit can be used for direct RT-PCR method and COVIDsure Pro kit performance was found to be superior among all.
Local, yet global: Implications of caste for MNEs and international business
Authors: Bapuji Hari , Chrispal Snehanjali , Vissa Balagopal , Ertug Gokhan 
Published: January 2023

AbstractCaste is an informal institution that influences socioeconomic action in many contexts. It is becoming increasingly evident that international business research, practice, and policy need to programmatically address caste. To facilitate this endeavor, we review the limited research in IB that has addressed caste, and theorize caste as a distinct informal institution by distinguishing it from other systems of stratification like race, class, and gender. In addition, we propose a parsimonious framework to highlight the implications of caste for Indian and non-Indian MNEs in their Indian and global operations. In doing this, we focus on implications with respect to the internal organization and inter-organizational relationships of MNEs, and consider how these implications might differ as based on the MNEs’ organizational forms. We then build on these implications to discuss how MNEs and other stakeholders of international business can address caste inequalities via policies related to human rights, anti-racism, and affirmative action. By bridging theory, practice, and policy, we pave the way for MNEs to address global inequalities that relate to caste.
Gain measurements on VCSEL material using segmented contact technique
Authors: Hentschel C , Allford C P , Gillgrass S-J , Travers-Nabialek J , Forrest R , Baker J , Meiklejohn J , Powell D , Meredith W , Haji M , Davies J I , Shutts S , Smowton P M 
Published: January 2023

Abstract
We report direct measurements of the optical gain on vertical-cavity surface-emitting laser (VCSEL) material using a stripe-length method featuring segmented contacts. We utilise the similarity of the in-plane transverse electric (TE) polarised matrix element and that of the VCSEL lasing mode and a simple method to reduce round trip effects. The confinement factor is determined from cold-cavity simulations of the in-plane TE polarised slab waveguide mode and used to convert the measured in-plane modal gain into the vertical-cavity modal gain, as required for the VCSEL structure. This gives a threshold material gain of 1440 ± 140 cm−1 at 30 °C for this structure. A comparison with the threshold material gain values determined from the lasing condition, where internal optical losses due to doping induced absorption is included using parameters taken from the literature, indicates the presence of an additional source of optical loss in the experiment which increases the threshold material gain by ∼450 cm−1. A best fit is obtained by increasing the optical loss in the n-DBR (distributed Bragg reflectors) layers to 40 cm−1, which is consistent with previous work on additional scattering losses due to interface roughening in the n-DBR layers. To further demonstrate the utility of this method for rapid optimisation, the gain-peak wavelength is measured directly, and its temperature dependence is compared to the lasing wavelength.
High-responsivity dual-frequency hot-electron photodetectors with magnetic polaritons beneath metal grating strips
Authors: Hu Xiao-long , Wu Hai-lin , Tang Ling-yun , Zhang Jiang , Liu Wen-jie 
Published: January 2023

Abstract
In this work, near-infrared Au-grating/MoS2/Au hot-electron photodetectors (HEPDs) with magnetic polaritons (MPs) beneath the top Au grating strips are designed and proposed. The MPs are formed by the near-field coupling between the grating and the bottom Au film, which achieves a light absorption greater than 99.5% at 1550 nm for the HEPDs. The simulations show that the absorption wavelength can be tuned independently and widely to cover the whole short wavelength infrared band by adjusting width of the grating strips, and the near-perfect absorption characteristics can be maintained. Then, dual-frequency HEPDs with two different grating strip widths in one cycle of the Au-grating are designed. Without external bias, the theoretical responsivities as high as 11.2 mA W−1 at 1200 nm and 6.2 mA W−1 at 1550 nm are achieved for the HEPDs by a three-step electrical model. In addition, a modulation distance between the two absorption peak positions of the HEPDs could be larger than 1100 nm. This provides a new idea for the realization of high-responsivity near-infrared HEPDs for arbitrary dual-band detection, which has great potential in modern optical communication systems.
Dyakonov surface polaritons in antiferromagnet film
Authors: Hao Shaopeng , Song Haoyuan , Fu Shufang , Wang Xuan-Zhang 
Published: January 2023

Abstract
Dyakonov surface polaritons (DSPs) in a single antiferromagnetic (AF) film are investigated in the parallel geometry where the AF anisotropic axis is parallel to the film and no external magnetic field is applied. The analytical dispersion relation is obtained and four surface modes are found, among which one symmetric mode and an anti-symmetric mode are exist in the AF reststrahlen frequency band, and another symmetric and anti-symmetric modes are situated out the reststrahlen band. The existence of symmetric and anti-symmetric modes is caused by the mirror symmetry and finite thickness of the AF film. A pair of modes in the band have magnetostatic limits but the other pair out the band do not. The dispersion properties, field and energy-flux density distributions of each DSP are numerically calculated based on the FeF2 film for various propagating directions and film thicknesses. It is very interesting that the energy flux of each DSP can seriously deviates from its propagation direction, and the largest walk-off angle can reach 200°. In addition, we briefly discuss dispersion properties of Dyakonov odd and even guided modes, they also are symmetric and antisymmetric and have multiple solutions.
Bias dependent NDR in TiO2/NiO heterojunction diodes
Authors: Athira M , Angappane S 
Published: January 2023

Abstract
TiO2/NiO thin film heterojunction diodes are fabricated using electron beam evaporation and DC sputtering techniques. Three different thicknesses of NiO (58, 82, and 160 nm) are combined with a TiO2 film of about 80 nm thick. The common device configuration is FTO/TiO2/NiO/Au with a 4 mm sq. device area. The thickness dependent diode I-V characteristics were analyzed; with the increase in thickness, the diode knee voltage, series resistance, and ideality factor have reduced. All the devices exhibit a high diode ideality factor, which means the diode currents are not limited by drift, diffusion, or recombination at the space charge region. The high ideality factor points to the presence of interface states, spatial inhomogeneities, or tunneling in the devices. Further, the bias dependent negative differential resistance (NDR) in I-V characteristics and the presence of an anomalous peak in C-V characteristics were analyzed, which claimed the presence of interfacial trap states, defects, or tunneling in the diodes. The Fowler-Nordheim tunnel model was applied to the devices and the field enhancement factors were calculated as −14.3, −9.3, and −9.2 for the diodes in the increasing order of thickness. The tunneling phenomenon was confirmed as trap-assisted indirect tunneling. Also, the temperature dependence of NDR was studied.
On the image method of separable variable problems
Authors: Zhang Yiming , Zhao Zhibin , Jiao Chongqing , Cui Xiang 
Published: January 2023

Abstract
The image method is a classical analysis method for mathematical physics problems but restricted by domain geometry and boundary conditions. In this paper, the scope of the image method is investigated and extended to separable variable problems. The general description of the image method is established and the image source distribution is determined for separable variable problems. The image source distribution function is proved to be the out of domain part of the eigenfunction series of the source distribution function. This continuation from the source distribution function to the image source distribution function is also given as the inner product with the eigenfunction series of the Dirac delta function. Three numerical examples with complex boundary conditions or geometry domains are prepared to verify the generality and effectiveness of the conclusion.
Dynamical analysis of higher-order localized waves for a three-component coupled nonlinear Schrödinger equation
Authors: Song N , Zhang Y F , Shang H J , Ma W X 
Published: January 2023

Abstract
This paper examines the three-component coupled nonlinear Schrödinger equation, which has various applications in deep ocean, nonlinear optics, Bose–Einstein (BE) condensates, and more. On the basis of seed solutions and a Lax pair, the Nth-order iterative expressions for the solutions are derived by using the generalized Darboux transformation. The evolution plots of dark-bright-rogue wave or breather-rogue wave are then obtained via numerical simulation. Particularly, a novel rogue wave propagation trajectory is found in the second and third order localized wave solutions. Moreover, by increasing the value of the free parameter α and β, the nonlinear waves merge with each other distinctly. The results further reveal the abundant dynamical patterns of localized waves in the three-component coupled system.
Kerr black holes with synchronised Proca hair: lensing, shadows and EHT constraints
Authors: Sengo Ivo , Cunha Pedro V.P. , Herdeiro Carlos A.R. , Radu Eugen 
Published: January 2023

Abstract
We investigate the gravitational lensing by spinning Proca stars and the shadows and lensing by Kerr black holes (BHs) with synchronised Proca hair, discussing both theoretical aspects and observational constraints from the Event Horizon Telescope (EHT) M87* and Sgr A* data. On the theoretical side, this family of BHs interpolates between Kerr-like solutions — exhibiting a similar optical appearance to that of Kerr BHs — to very non-Kerr like solutions, exhibiting exotic features such as cuspy shadows, egg-like shadows and ghost shadows. We interpret these features in terms of the structure of the fundamental photon orbits, for which different branches exist, containing both stable and unstable orbits, with some of the latter not being shadow related. On the observational side, we show that current EHT constraints are compatible with all such BHs that could form from the growth of the superradiant instability of Kerr BHs. Unexpectedly, given the (roughly) 10% error bars in the EHT data — and in contrast to their scalar cousin model —, some of the BHs with up to 40% of their energy in their Proca hair are compatible with the current data. We estimate the necessary resolution of future observations to better constrain this model.
Interface engineering in two-dimensional heterostructures towards novel emitters
Authors: Li Hua , Ling Jinyang , Lin Jiamin , Lu Xin , Xu Weigao 
Published: January 2023

Abstract
Two-dimensional (2D) semiconductors have captured broad interest as light emitters, due to their unique excitonic effects. These layer-blocks can be integrated through van der Waals assembly, i.e., fabricating homo- or heterojunctions, which show novel emission properties caused by interface engineering. In this review, we will first give an overview of the basic strategies that have been employed in interface engineering, including changing components, adjusting interlayer gap, and tuning twist angle. By modifying the interfacial factors, novel emission properties of emerging excitons are unveiled and discussed. Generally, well-tailored interfacial energy transfer and charge transfer within a 2D heterostructure cause static modulation of the brightness of intralayer excitons. As a special case, dynamically correlated dual-color emission in weakly-coupled bilayers will be introduced, which originates from intermittent interlayer charge transfer. For homobilayers and type Ⅱ heterobilayers, interlayer excitons with electrons and holes residing in neighboring layers are another important topic in this review. Moreover, the overlap of two crystal lattices forms moiré patterns with a relatively large period, taking effect on intralayer and interlayer excitons. Particularly, theoretical and experimental progresses on spatially modulated moiré excitons with ultra-sharp linewidth and quantum emission properties will be highlighted. Moiré quantum emitter provides uniform and integratable arrays of single photon emitters that are previously inaccessible, which is essential in quantum many-body simulation and quantum information processing. Benefiting from the optically addressable spin and valley indices, 2D heterostructures have become an indispensable platform for investigating exciton physics, designing and integrating novel concept emitters.