bluuebunny/crossref_metadata_2025 huggingface dataset:
Infectious bursal disease virus: predicting viral pathotype using machine learning models focused on early changes in total blood cell counts
Authors: Molinet Annonciade , Courtillon Céline , Bougeard Stéphanie , Keita Alassane , Grasland Béatrice , Eterradossi Nicolas , Soubies Sébastien
Published: October 2023

Infectious bursal disease (IBD) is an avian viral disease caused in chickens by infectious bursal disease virus (IBDV). IBDV strains (Avibirnavirus genus, Birnaviridae family) exhibit different pathotypes, for which no molecular marker is available yet. The different pathotypes, ranging from sub-clinical to inducing immunosuppression and high mortality, are currently determined through a 10-day-long animal experiment designed to compare mortality and clinical score of the uncharacterized strain with references strains. Limits of this protocol lie within standardization and the extensive use of animal experimentation. The aim of this study was to establish a predictive model of viral pathotype based on a minimum number of early parameters measured during infection, allowing faster pathotyping of IBDV strains with improved ethics. We thus measured, at 2 and 4 days post-infection (dpi), the blood concentrations of various immune and coagulation related cells, the uricemia and the infectious viral load in the bursa of Fabricius of chicken infected under standardized conditions with a panel of viruses encompassing the different pathotypes of IBDV. Machine learning algorithms allowed establishing a predictive model of the pathotype based on early changes of the blood cell formula, whose accuracy reached 84.1%. Its accuracy to predict the attenuated and strictly immunosuppressive pathotypes was above 90%. The key parameters for this model were the blood concentrations of B cells, T cells, monocytes, granulocytes, thrombocytes and erythrocytes of infected chickens at 4 dpi. This predictive model could be a second option to traditional IBDV pathotyping that is faster, and more ethical.
Female unemployment, mobile money innovations and doing business by females
Authors: Asongu Simplice A. , Odhiambo Nicholas M.
Published: October 2023

The purpose of this study is to complement extant literature by examining how mobile money innovations can moderate the unfavorable incidence of female unemployment on female doing of business in 44 countries from sub-Saharan Africa for the period 2004 to 2018. The empirical evidence is based on interactive quantile regressions. The employed doing business constraints are the procedures a woman has to go through to start a business and the time for women to set up a business, while the engaged mobile money innovations are: (i) registered mobile money agents (registered mobile money agents per 1000 km2 and registered mobile money agents per 100,000 adults) and (ii) active mobile money agents (active mobile money agents per 1000 km2 and active mobile money agents per 100,000 adults). The hypothesis that mobile money innovation moderates the unfavorable incidence of female unemployment on business constraints is overwhelmingly invalid. The invalidity of the tested hypothesis is clarified, and the policy implications are discussed.
Imaging glymphatic response to glioblastoma
Authors: Kaur Jasleen , Ding Guangliang , Zhang Li , Lu Yong , Luo Hao , Li Lian , Boyd Edward , Li Qingjiang , Wei Min , Zhang Zhenggang , Chopp Michael , Jiang Quan
Published: October 2023

Background

The glymphatic system actively exchanges cerebrospinal fluid (CSF) and interstitial fluid (ISF) to eliminate toxic interstitial waste solutes from the brain parenchyma. Impairment of the glymphatic system has been linked to several neurological conditions. Glioblastoma, also known as Glioblastoma multiforme (GBM) is a highly aggressive form of malignant brain cancer within the glioma category. However, the impact of GBM on the functioning of the glymphatic system has not been investigated. Using dynamic contrast-enhanced magnetic resonance imaging (CE-MRI) and advanced kinetic modeling, we examined the changes in the glymphatic system in rats with GBM.

Methods

Dynamic 3D contrast-enhanced T1-weighted imaging (T1WI) with intra-cisterna magna (ICM) infusion of paramagnetic Gd-DTPA contrast agent was used for MRI glymphatic measurements in both GBM-induced and control rats. Glymphatic flow in the whole brain and the olfactory bulb was analyzed using model-derived parameters of arrival time, infusion rate, clearance rate, and residual that describe the dynamics of CSF tracer over time.

Results

3D dynamic T1WI data identified reduced glymphatic influx and clearance, indicating an impaired glymphatic system due to GBM. Kinetic modeling and quantitative analyses consistently indicated significantly reduced infusion rate, clearance rate, and increased residual of CSF tracer in GBM rats compared to control rats, suggesting restricted glymphatic flow in the brain with GBM. In addition, our results identified compromised perineural pathway along the optic nerves in GBM rats.

Conclusions

Our study demonstrates the presence of GBM-impaired glymphatic response in the rat brain and impaired perineural pathway along the optic nerves. Reduced glymphatic waste clearance may lead to the accumulation of toxic waste solutes and pro-inflammatory signaling molecules which may affect the progression of the GBM.
Inflammasomes in rheumatoid arthritis: a pilot study
Authors: Jiang Qi , Wang Xin , Xu Xiuping , Hu Liangfeng , Zhou Guozhong , Liu Rui , Yang Guocan , Cui Dawei
Published: October 2023

Background

The inflammasome plays an important role in rheumatoid arthritis (RA), which has rarely been systematically reported. The aim of this study was to understand whether the levels of inflammasomes were related to the severity of RA disease, which might provide a stronger theoretical basis for RA treatment.

Methods

The mRNA expression levels of some inflammasomes and associated molecules, including IL-1beta and IL-18, in peripheral blood mononuclear cells (PBMCs) from 30 RA patients (n = 30) and 16 healthy control (HC) individuals were determined by quantitative real-time polymerase chain reaction (qRT‒PCR), and the levels of plasma IL-1beta and IL-18 were also measured by enzyme-linked immunosorbent assay (ELISA). Moreover, the clinical characteristics and laboratory results of the patients were collected and analyzed in this study.

Results

The relative mRNA expression levels of NLRP3, NLRC4, AIM2, caspase-1, and IL-1beta were significantly higher and those of NLRP1, NLRP2 and NLRC5 were notably lower in the HC group than in the RA group. Moreover, the plasma IL-1beta and IL-18 levels were markedly increased in the RA group. Additionally, the mRNA level of AIM2 was negatively correlated with disease activity score 28 (DAS28) by stepwise linear regression analysis. erythrocyte sedimentation rate (ESR) was positively correlated with DAS28 by multiple linear regression analysis in the RA group.

Conclusions

These findings imply the critical role of NLRP3, NLRC4, AIM2, caspase-1 and plasma IL-1beta and IL-18 in the pathogenesis of RA patients, which provides potential targets for the treatment of RA.
Traffic light alarming signs are indispensable prerequisites for fruitful endoscopic third ventriculostomy
Authors: Nagm Alhusain
Published: October 2023

Background

Endoscopic third ventriculostomy (ETV) is a satisfying neuro-endoscopic journey in candidates with preoperatively predicted higher success rates. Alarming cases require extra care to avoid serious complications, predict/identify failure and offer reasonable intra-/postoperative decisions.

Purpose

To create easily interpretable traffic light alarming signs to increase the awareness level for neurosurgeons regarding ETV difficulty/failure.

Methods

A 3-year-retrospective study of postoperative ETV infants of both sexes with obstructive hydrocephalus and preoperative ETV success score ≤ 70, age ≤ 12 months, and follow-up for ≥ 6 months with a postoperative radiological evaluation of the ETV patency and cerebrospinal fluid dynamics. The ETV difficulty scale (ETV-DS) was designed as an intraoperative monitor for surgical/anatomical difficulties. And the ETV failure threshold (ETV-FT) was offered for postoperative evaluation to identify cases that are mistakenly interpreted as failure.

Results

Among our 159 case series, 54 infants were involved. Patients’ demographics, age: ≤ 28 days, > 28 days to 6 months, and >6 to 12 months, were 5.5%, 70.3%, and 24.2%, respectively. Postoperatively, the outcome based on ETV-FT color scale was dark green (ETV-FT=0), light green (ETV-FT=1), yellow (ETV-FT=2), orange (ETV-FT=3), red (ETV-FT=4) in 29%, 14%, 20%, 10.3%, and 26.7%, respectively. Actual failure is identified as ETV-FT=4 based on clinical/radiological data. The failure rate was significantly attributed to inadequate communication with the basal cistern due to difficult/unsafe perforation of the thick/dense Liliequist membrane (87%) (P = 0.001).

Conclusion

The traffic light alarming signs (ETV-DS and ETV-FT) can warn neurosurgeons to recognize critical cases that necessitate ultra-precautions to navigate safely through landmines for worthy outcomes.
Does cadmium cause cascading effects on the development and reproduction of the striped stem borer, Chilo suppressalis (Walker)?
Authors: Huang Hexi , Di Ning , Wang Jie , Wang Yuxing , Zhu Zhengyang , Lu Caige , Wang Su , Zang Liansheng
Published: October 2023

The heavy metal, cadmium (Cd), causing growth retardation and yield reduction on rice and impacting the fitness of organisms inhabiting on rice through bottom-up effects, has become a great challenge to rice production. However, the effect of Cd-exposure on the development of an economically important and destructive rice pest, Chilo suppressalis remains unexplored. By exposing the larvae of C. suppressalis to different Cd-exposed artificial diets (0, 0.2, 1.0, 2.5, 5.0, and 10.0 mg/kg), we found that Cd exposure did not affect the larval duration or pupation rate of C. suppressalis, but caused negative effects on pupal weight at high Cd levels (5.0 and 10.0 mg/kg) and on adult deformity rate from 2.5 and 5.0 mg/kg treatments. Although Cd significantly increased the female pupae ratio, C. suppressalis did not oviposit when Cd treatment was more than 2.5 mg/kg. Meanwhile, Cd transferred to pupae, females, exuviae of pupa and eggs of C. suppressalis from Cd treated larvae, and exhibited a dose-dependent response on Cd accumulation. Our results indicated that Cd had a negative effect on rice stem borer and can be transferred to eggs of C. suppressalis, but more work is needed to further assess the bottom-up effect on third tropic levels in Cd-polluted fields.
Quantitative prediction of the fracture scale based on frequency-dependent S-wave splitting
Authors: Yu Peilin , Yang Yuyong , Qi Qiaomu , Zhou Huailai , Wang Yuanjun
Published: October 2023

The development of natural fractures has a significant impact on underground reservoirs and leads to seismic anisotropy. Furthermore, the scale of natural fractures directly affects oil and gas preservation, hydraulic fracture construction, and the production development of shale reservoirs. The S-wave anisotropy is a frequency-dependent parameter and the change in S-wave anisotropy with frequency is a function of the fracture scale. We develop an innovative method for predicting the fracture scale quantitatively using frequency-dependent S-wave anisotropy. The quantitative relationship between different fracture scales and the frequency-dependent response of the S-wave splitting (SWS) anisotropy can be obtained using a dynamic rock-physics model. The frequency-dependent S-wave anisotropy is calculated via SWS analysis in the frequency domain, after which this quantitative relationship and the calculated frequency-dependent response are used to establish an objective function for the inversion of the fracture scale at different depths using the least-squares algorithm. We synthesize data under ideal conditions, test our method, apply our method to field data, and find that the quantitative prediction method of the fracture scale yielded reasonable prediction results. The S-wave anisotropy is calculated based on the SWS analysis from the horizontal components of the upgoing wavefields of the field vertical seismic profile. We compare the fracture scale calculated from logging data using our method, and the results obtained indicate that this method can successfully predict the fracture scale quantitatively.
Embryonic organizer specification in the mud snail Ilyanassa obsoleta depends on intercellular signaling
Authors: Wandelt Jessica E. , Nakamoto Ayaki , Goulding Morgan Q. , Nagy Lisa M.
Published: October 2023

In early embryos of the caenogastropod snail Ilyanassa obsoleta, cytoplasmic segregation of a polar lobe is required for establishment of the D quadrant founder cell, empowering its great-granddaughter macromere 3D to act as a single-celled organizer that induces ectodermal pattern along the secondary body axis of the embryo. We present evidence that polar lobe inheritance is not sufficient to specify 3D potential, but rather makes the D macromere lineage responsive to some intercellular signal(s) required for normal expression of 3D-specific phenotypes. Experimental removal of multiple micromeres resulted in loss of organizer-linked MAPK activation, complete and specific defects of organizer-dependent larval organs, and progressive cell cycle retardation, leading to equalization of the normally accelerated division schedule of 3D (relative to the third-order macromeres of the A, B and C quadrants). Ablation of the second-quartet micromere 2d greatly potentiated the effects of first micromere quartet ablation. Our findings link organizer activation in I. obsoleta to the putative ancestral spiralian mechanism in which a signal from micromeres leads to specification of 3D among four initially equivalent macromeres.
Episodic live imaging of cone photoreceptor maturation in GNAT2-EGFP retinal organoids
Authors: Bai Jinlun , Koos David S. , Stepanian Kayla , Fouladian Zachary , Shayler Dominic W. H. , Aparicio Jennifer G. , Fraser Scott E. , Moats Rex A. , Cobrinik David
Published: October 2023

Fluorescent reporter pluripotent stem cell-derived retinal organoids are powerful tools to investigate cell type-specific development and disease phenotypes. When combined with live imaging, they enable direct and repeated observation of cell behaviors within a developing retinal tissue. Here, we generated a human cone photoreceptor reporter line by CRISPR/Cas9 genome editing of WTC11-mTagRFPT-LMNB1 human induced pluripotent stem cells (iPSCs) by inserting enhanced green fluorescent protein (EGFP) coding sequences and a 2A self-cleaving peptide at the N-terminus of guanine nucleotide-binding protein subunit alpha transducin 2 (GNAT2). In retinal organoids generated from these iPSCs, the GNAT2-EGFP alleles robustly and exclusively labeled immature and mature cones. Episodic confocal live imaging of hydrogel immobilized retinal organoids allowed tracking of the morphological maturation of individual cones for >18 weeks and revealed inner segment accumulation of mitochondria and growth at 12.2 μm3 per day from day 126 to day 153. Immobilized GNAT2-EGFP cone reporter organoids provide a valuable tool for investigating human cone development and disease.
Human sperm rotate with a conserved direction during free swimming in four dimensions
Authors: Corkidi Gabriel , Montoya Fernando , González-Cota Ana L. , Hernández-Herrera Paul , Bruce Neil C. , Bloomfield-Gadêlha Hermes , Darszon Alberto
Published: October 2023

Head rotation in human spermatozoa is essential for different swimming modes and fertilisation, as it links the molecular workings of the flagellar beat with sperm motion in three-dimensional (3D) space over time. Determining the direction of head rotation has been hindered by the symmetry and translucent nature of the sperm head, and by the fast 3D motion driven by the helical flagellar beat. Analysis has been mostly restricted to two-dimensional (2D) single focal plane image analysis, which enables tracking of head centre position but not tracking of head rotation. Despite the conserved helical beating of the human sperm flagellum, human sperm head rotation has been reported to be uni- or bi-directional, and even to intermittently change direction in a given cell. Here, we directly measure the head rotation of freely swimming human sperm using multi-plane 4D (3D+t) microscopy and show that: (1) 2D microscopy is unable to distinguish head rotation direction in human spermatozoa; (2) head rotation direction in non-capacitating and capacitating solutions, for both aqueous and viscous media, is counterclockwise (CCW), as seen from head to tail, in all rotating spermatozoa, regardless of the experimental conditions; and (3) head rotation is suppressed in 36% of spermatozoa swimming in non-capacitating viscous medium, although CCW rotation is recovered after incubation in capacitating conditions within the same viscous medium, possibly unveiling an unexplored aspect of the essential need of capacitation for fertilisation. Our observations show that the CCW head rotation in human sperm is conserved. It constitutes a robust and persistent helical driving mechanism that influences sperm navigation in 3D space over time, and thus is of critical importance in cell motility, propulsion of flagellated microorganisms, sperm motility assessments, human reproduction research, and self-organisation of flagellar beating patterns and swimming in 3D space.
Scoring thermal limits in small insects using open-source, computer-assisted motion detection
Authors: Perez-Galvez Fernan R. , Zhou Sophia , Wilson Annabelle C. , Cornwell Catherine L. , Awde David N. , Teets Nicholas M.
Published: October 2023

Scoring thermal tolerance traits live or with recorded video can be time consuming and susceptible to observer bias, and as with many physiological measurements, there can be trade-offs between accuracy and throughput. Recent studies show that automated particle tracking is a viable alternative to manually scoring videos, although some of the software options are proprietary and costly. In this study, we present a novel strategy for automated scoring of thermal tolerance videos by inferring motor activity with motion detection using an open-source Python command line application called DIME (detector of insect motion endpoint). We apply our strategy to both dynamic and static thermal tolerance assays, and our results indicate that DIME can accurately measure thermal acclimation responses, generally agrees with visual estimates of thermal limits, and can significantly increase throughput over manual methods.
A Sufficient Statistics Approach for Macro Policy
Authors: Barnichon Régis , Mesters Geert
Published: October 2023

The evaluation of macroeconomic policy decisions has traditionally relied on the formulation of a specific economic model. In this work, we show that two statistics are sufficient to detect, often even correct, nonoptimal policies, i.e., policies that do not minimize the loss function. The two sufficient statistics are (i) forecasts for the policy objectives conditional on the policy choice and (ii) the impulse responses of the policy objectives to policy shocks. Both statistics can be estimated without relying on a specific structural economic model. We illustrate the method by studying US monetary policy decisions. (JEL E24, E31, E32, E43, E52, E58)
Descuento sexual y conductas sexuales arriesgadas en una muestra de adultos jóvenes de Colombia
Authors: Soares-Filho Paulo Sergio Dillon
Published: October 2023

El objetivo del presente trabajo fue describir la tasa de descuento sexual y evaluar la relación entre el autorreporte de Conductas Sexuales Arriesgadas (CSA) y el descuento sexual en una muestra de adultos jóvenes en Colombia. Para esto, se realizó una investigación no experimental de corte transversal y correlacional. 139 participantes fueron sometidos a un cuestionario de Autorreporte de Conductas de Riesgo Sexual, la Tarea de Descuento Sexual (SDDT) y el Cuestionario de Elección Monetaria (MCQ). Los análisis de la curva de descuento sexual demuestran que el valor de la opción de tener sexo seguro disminuye con el incremento en la demora en la obtención de un condón (i.e. descuento sexual). Adicionalmente, se observa que el grado de descuento sexual está asociado con CSA, como el número de parejas sexuales y el número de relaciones sexuales en los últimos 3 meses y que hay una diferencia en el patrón de descuento sexual entre hombres y mujeres.
Thrombocytopenia induced by clopidogrel: a rare adverse effect
Authors: Távora Catarina , Rodrigues dos Santos Joana , Cruz Diogo
Published: October 2023

Introduction: Immune thrombocytopenic purpura (ITP) can be induced by several drugs but there are few case reports of ITP induced by clopidogrel. Second-line treatment with thrombopoietin receptor agonists (TPO-RA) presents solid evidence and should be considered in patients in need of elective surgery who are poor responders to steroids. Case description: We report the case of a 79-year-old male who developed severe immune thrombocytopenic purpura after initiating treatment with clopidogrel. Because he needed elective orthopaedic surgery and he did not respond to corticotherapy and immunoglobulin, second-line treatment with romiplostim was initiated with a significant increase in platelet count. Discussion and conclusion: Clopidogrel can induce ITP and this diagnosis should be considered in patients who present with isolated thrombocytopenia. First-line therapy of ITP is not always successful; second-line treatment with TPO-RA has a high response rate and should be considered in patients in need of elective surgery who have failed to respond to first-line therapy.
NSAIDs linked to IgA-mediated hypersensitivity vasculitis and purpura fulminans-like eruption
Authors: Levenberg Guy , Bleier Jonathan , Leibowitz Avshalom , Salomon Ophira , Misgav Mudi , Agmon-Levin Nancy , Shavit Ronen
Published: October 2023

Background: IgA vasculitis and hypersensitivity reactions following exposure to non-steroidal anti-inflammatory drugs (NSAIDs) are very rarely associated with purpura fulminans (PF). The latter is a coagulation event characterised by decreased levels of protein C and a rapidly progressive purpuric rash, often leading to ischaemia, amputations and death. Case summary: A previously healthy 66-year-old man presented with a vasculitic rash and abdominal pain following exposure to naproxen (NSAID), which quickly deteriorated to purpura fulminans-like eruption and skin necrosis, mainly involving the face and hands. The presence of IgA sediments on skin biopsy and decreased levels of complement as well as protein C pointed to an immune-mediated inflammatory process. Dramatic clinical escalation with immediate risk to organs and life required an aggressive and broad-spectrum therapeutic approach in an intensive care setting. Clinical improvement and complete reconstitution of protein C were achieved following plasma exchange with fresh frozen plasma (FFP) and immunosuppression with glucocorticoids with no persistent organ damage. Conclusions: This rare case illustrates the catastrophic cross links between NSAIDs, IgA-mediated hypersensitivity vasculitis and purpura fulminans-like syndrome. A high index of suspicion is required for the evaluation of environmental exposures such as drugs and infections in patients with vasculitis and/or purpura. A rapid and comprehensive therapeutic approach should be implemented to avoid multi-organ damage, amputations and death. Complete avoidance of the offending agent is key for future prevention of recurrence.
Lutembacher’s syndrome accompanied by partial anomalies of pulmonary veins in a 70-year-old male: a case of congenital heart disease in the elderly
Authors: Khattab Mohammad Nasser , Alhalabi Mohammad , Alkounsol Karam , Othman Majed , Hujair Nizar
Published: October 2023

Lutembacher’s syndrome is a rare disease defined as the combination of atrial septal defect and mitral stenosis, which relieves the progression of symptoms resulting from mitral stenosis. We present a case of a previously asymptomatic 70-year-old man having Lutembacher’s syndrome with sinus venosus type of interatrial defect associated with partial anomalous pulmonary venous drainage. Our patient’s only complaint was of mild exertional dyspnea, which started six months prior to referral. Clinical suspicion of the combination of defects arose during transthoracic echocardiography. The patient underwent transesophageal echocardiography and multi-slice computed tomography for defect confirmation. The combination of Lutembacher’s syndrome with this complex deformity of pulmonary venous drainage has rarely been described. Such complex congenital defects with multifaceted physiological repercussions can go largely undiagnosed for the patients affected for most of their lifetimes.
MEDIATING BRAND TRUST, BRAND ATTITUDE, BRAND PSYCHOLOGICAL OWNERSHIP ON CELEBRITY ENDORSERS TO BEHAVIOURAL INTENTION
Authors: Safira Elsi , Fatmawati Indah , Nuryakin Nuryakin
Published: October 2023

The marketing type that is found on social media today is celebrity endorsement. To encourage consumer behavioural intention, luxury brand companies take several strategies, including using celebrity endorsers to introduce their brand and to build brand trust, brand attitude, and brand psychological ownership. This study aims to examine the influence of celebrity endorsers on behavioural intention through the mediation of brand trust, attitude, and psychological ownership. A total of 250 samples were determined by purposive sampling. This research used a quantitative approach and structural equation modelling (SEM) AMOS as a data analysis technique. The result showed a mediating effect of brand trust, attitude, and psychological ownership on the relationship between celebrity endorsers and behavioural intention.
Poverty reduction through vocational and technical education among graduates in Oyo State, Nigeria
Authors: Salami Sarafadeen Segun , Afolabi Oluwatunmise
Published: October 2023

Poverty and unemployment especially among the graduates has remained major challenges threating the economic growth and development of Nigeria. Towards poverty reduction Vocational and technical education is imperative. Therefore, this study examined poverty reduction through vocational and technical education among graduates in Oyo State, Nigeria. Four (4) research questions guided the study. The study adopted descriptive survey design. A total of 390 vocational and technical education students formed the sample size of the study out of 3,900 graduates. A structured questionnaire developed by the researchers tagged: Poverty Reduction through Vocational and Technical Education Questionnaire (PRVTEQ) validated by three (3) experts was used for the study. Split half method was used to established reliability coefficient and the overall reliability coefficient was also established at 0.87 using Cronbach Alpha. The data generated for the study were analysed using mean and standard deviation. The findings showed among others that vocational and technical education increase pace for technological innovations, improve citizens standard of living, facilitate social Economy growth and development and promote political stability. Based on the findings the researcher recommended among others, government through its agencies should map out strategies of reaching out and providing funds for individuals who are willing to set up businesses and that school management should provide more vocational centers for skills acquisition towards poverty reduction.
Semiclassical calculation of the power saturation of the Kerr effect in Rb vapor
Authors: Levine Zachary H. , Du Ziran
Published: October 2023

The Kerr effect in atomic vapor may be regarded as the power saturation of the susceptibility. Hence the saturable Kerr effect is intimately tied to the standard Kerr effect. Here, we calculate the saturable Kerr effect without free parameters using a two-level system and find good agreement with experimental results. Our approach permits a direct comparison of theory to experiment without an extrapolation to low power as required by previous approaches. An experimentally observed asymmetry between red and blue detuning led us to consider a model with one ground state and three excited states. Such an asymmetry cannot be described by a two-state model. The model predicts about 25% of the observed asymmetry.
Evaluation of beam shape coefficients in T-matrix methods using a finite series technique: on blow-ups using hypergeometric functions and generalized Bessel polynomials
Authors: Gouesbet Gérard , Votto Luiz F. M. , Ambrosio Leonardo A.
Published: October 2023

In T-matrix methods (generalized Lorenz–Mie theories or extended boundary condition method), beam shape coefficients encoding the shape of the illuminating structured beam have to be evaluated. This may be carried out by using the finite series technique, which, however, generates blow-ups when the partial wave order of the beam shape coefficients increases. Using hypergeometric functions and generalized Bessel polynomials, we demonstrate in the case of on-axis Gaussian beams that these blow-ups are genuine phenomena, not due to a lack of numerical precision, and we establish criteria to evaluate the critical partial wave order that implies blow-ups.
Measurement device hacking-free mutual quantum identity authentication over a deployed optical fiber
Authors: Choi Ji-Woong , Park Chang Hoon , Lim Na-Hee , Woo Min Ki , Kang Min-Sung , Han Sang-Wook
Published: October 2023

Quantum identity authentication serves as a crucial technology for secure quantum communication, but its security often faces challenges due to quantum hacking of measurement devices. This study introduces a measurement-device-independent mutual quantum identity authentication (MDI MQIA) scheme capable of ensuring secure user authentication, despite the use of measurement devices vulnerable to quantum hacking. To realize the MDI MQIA scheme, we proposed and applied a modified Bell state measurement based on linear optics, enabling the probabilistic measurement of all Bell states. Furthermore, the proposed experimental setup adopted a plug-and-play architecture, thus efficiently establishing the indistinguishability of two photons prepared by the communication members. Finally, we successfully performed a proof-of-principle experimental demonstration of the proposed scheme using a field-deployed fiber, achieving quantum bit error rates of less than 3%.
Super-resolution non-line-of-sight imaging based on temporal encoding
Authors: Miao Jinye , Guo Enlai , Shi Yingjie , Cai Fuyao , Bai Lianfa , Han Jing
Published: October 2023

Non-line-of-sight (NLOS) imaging techniques have the ability to reconstruct objects beyond line-of-sight view, which would be useful in a variety of applications. In transient NLOS techniques, a fundamental problem is that the time resolution of imaging depends on the single-photon timing resolution (SPTR) of a detector. In this paper, a temporal super-resolution method named temporal encoding non-line-of-sight (TE-NLOS) is proposed. Specifically, by exploiting the spatial-temporal correlation among transient images, high-resolution transient images can be reconstructed through modulator encoding. We have demonstrated that the proposed method is capable of reconstructing transient images with a time resolution of 20 picoseconds from a detector with a limited SPTR of approximately nanoseconds. In systems with low time jitter, this method exhibits superior accuracy in reconstructing objects compared to direct detection, and it also demonstrates robustness against miscoding. Utilizing high-frequency modulation, our framework can reconstruct accurate objects with coarse-SPTR detectors, which provides an enlightening reference for solving the problem of hardware defects.
Monolithic 2-µm single-frequency linearly-polarized gain-switched distributed feedback fiber laser by femtosecond laser direct-writing
Authors: Shi Jindan , Wei Ling , Li Yifei , Feng Xian
Published: October 2023

We report a single-frequency, linearly polarized gain-switched, distributed feedback (DFB), 2-µm thulium doped silica fiber laser (TDFL), with an effective cavity length of 2.5 mm. The cavity is based on a heavily thulium doped non-polarization-maintaining silica fiber and composed of a π-phase-shifted fiber Bragg grating (FBG) with a total FBG length of 35 mm. The DFB FBG was written by femtosecond-laser point-by-point (PbP) method. In-band pumping scheme is chosen with a 1550 nm nanosecond pulsed erbium-doped silica fiber laser pump. Single-longitudinal, linearly polarized, gain-switched TDFL at 2002 nm, with a recorded shortest pulse duration of 4.7 ns, a repetition rate of 20 kHz, a maximum peak power of 170 W, and single pulse energy of 0.8 µJ, has been obtained, benefitting from the ultrashort DFB cavity made by the femtosecond laser direct-writing method.
Influence of growth interruption on the morphology and luminescence properties of AlGaN/GaN ultraviolet multi-quantum wells
Authors: Hou Yufei , Wang Baibin , Yang Jing , Zhang Yuheng , Zhang Zhen zhuo , Liang Feng , Liu Zongshun , Zhao Degang
Published: October 2023

The influence of growth interruption on the surface and luminescence properties of AlGaN/GaN ultraviolet multi-quantum wells (UV MQWs) is investigated. It is found that when the well and barrier layers of MQW samples are continuously grown at the same temperature, they have lower edge dislocation density and flatter surface of MQWs compared to samples with interrupted well and barrier growth. Moreover, continuous growth of well and barrier layers is more conducive to improving the luminescence efficiency of MQWs. This phenomenon is attributed to more impurity incorporation induced by the growth interruption, while a continuous growth of well and barrier can reduce surface diffusion and migration processes of atoms, reducing the defects and surface roughness of MQWs. In addition, the continuous growth of well and barrier can better control the reaction between Al and N atoms, avoiding the formation of excessively high Al content AlGaN at the well/barrier interface, thus improving the luminescence of UV MQWs.
Real-time 3D shape measurement of dynamic scenes using fringe projection profilometry: lightweight NAS-optimized dual frequency deep learning approach
Authors: Li Yueyang , Wu Zhouejie , Shen Junfei , Zhang Qican
Published: October 2023

Achieving real-time and high-accuracy 3D reconstruction of dynamic scenes is a fundamental challenge in many fields, including online monitoring, augmented reality, and so on. On one hand, traditional methods, such as Fourier transform profilometry (FTP) and phase-shifting profilometry (PSP), are struggling to balance measuring efficiency and accuracy. On the other hand, deep learning-based approaches, which offer the potential for improved accuracy, are hindered by large parameter amounts and complex structures less amenable to real-time requirements. To solve this problem, we proposed a network architecture search (NAS)-based method for real-time processing and 3D measurement of dynamic scenes with rate equivalent to single-shot. A NAS-optimized lightweight neural network was designed for efficient phase demodulation, while an improved dual-frequency strategy was employed coordinately for flexible absolute phase unwrapping. The experiment results demonstrate that our method can effectively perform 3D reconstruction with a reconstruction speed of 58fps, and realize high-accuracy measurement of dynamic scenes based on deep learning for what we believe to be the first time with the average RMS error of about 0.08 mm.
Enhanced light extraction efficiency of GaN-based green micro-LED modulating by a thickness-tunable SiO2 passivation structure
Authors: Yan Xing , Hu Xun , Zhou Rui , Gao Na , Yao Yuchao , Gao Yujie , Kang Junyong
Published: October 2023

Green micro-light emitting diodes (micro-LEDs) is one of the three primary color light sources as full-color display, which serves as a key research object in the field of micro-LED display. As the micro-LED size decreases, the surface-area-to-volume ratio of the device increases, leading to more serious damage on the sidewall by inductively coupled plasma (ICP) etching. The passivation process of SiO2 provides an effective method to reduce sidewall damage caused by ICP etching. In this work, green rectangular micro-LEDs with passivation layer thickness of 0∼600 nm was designed using the finite-difference time-domain (FDTD) simulation. In order to verify the simulation results, the micro-LED array was fabricated by parallel laser micro-lens array (MLA) lithography in high speed and large area. The effect of the SiO2 passivation layer thickness on the performance of the green micro-LED was analyzed, which shows that the passivation layer thickness-light extraction efficiency curve fluctuates periodically. For the sample with 90 nm thickness of SiO2 passivation layer, there exists a small leakage current and higher operating current density, and the maximum external quantum efficiency (EQE) is 2.8 times higher than micro-LED without SiO2 passivation layer.
Wide-field time-of-flight measurements of highly scattering media
Authors: Stefanov André , Tijkorte Pascal , Hannink Gijs , Roth Lynn , Frenz Martin
Published: October 2023

We present a setup that makes use of a time-resolved single-photon camera to determine the scattering parameters of media. The measurement is realized in a non-contact way, both for the illumination laser and the detection. By fitting the time-of-flight acquired distributions at different spatial positions with the diffusion equation, we retrieve the reduced scattering coefficients of a highly diffusive isotropic reference media for wavelengths in the range from 540 to 840 nm.
Polar optical flow network: extracting overlapped holograms of dynamic particles
Authors: Chen Zhenxi , Xu Jie , Zhong Liyun , Lu Xiaoxu , Tian Jindong
Published: October 2023

Digital holography with lensless in-line setup has been extensively used in particle field measurements. As particle concentration increases, the holograms of dynamic particles locating at different depths tend to superpose with each other with incoherent overlap, hampering effective measurement of individual particles with incomplete information. Drawing inspiration from suborbicular nature of the in-line holographic fringes, in this study, we propose an optical flow method in polar coordinates to mitigate the overlap issue. The approach employs a radial transformer-enhanced network that leverages both the radial and angular characteristics of the polar hologram. Through ablation tests and experimental results, we have demonstrated the effectiveness and superiority of our proposed method.
Inverse design of a light nanorouter for a spatially multiplexed optical filter
Authors: Peng Yu Qi , Lu Hai Peng , Zhang Da Sen , Wang Li Cheng , Ma Zhan Ying , Xiao Jun Jun
Published: October 2023

It is attractive to use an optical nanorouter by artificial nanostructures to substitute the traditional Bayer filter for an image array sensor, which, however, poses great challenges in balancing the design strategy and the ease of fabrication. Here, we implement and compare two inverse design schemes for rapid optimization of RGGB Bayer-type optical nanorouter. One is based on the multiple Mie scattering theory and the adjoint gradient that is applicable to arrays of nanospheres with varying sizes, and the other is based on the rigorous coupled wave analysis and the genetic algorithm. In both cases, we study layered nanostructures that can be efficiently modeled respectively which greatly accelerates the inverse design. It is shown that the color-dependent peak collection efficiencies of nanorouters designed in the two methods for red, green, and blue wavelengths reach 37%, 44%, and 45% and 52%, 50%, and 66%, respectively. We further demonstrate color nanorouters that provide light focusing to four quadrants working in both the visible and infrared bands, which promises multispectral imaging applications.
AI-algorithm-assisted 895-nm praseodymium laser emitting sub-100-fs pulses
Authors: Luo Saiyu , Wang Hanyu , Jiang XingChen , Chen Gezhi , Qiu Chen , Tian Yu , Wang Tianyue , Pan Shiyi , Xue Junhao , Li Li , Cai Zhiping
Published: October 2023

Praseodymium (Pr) lasers have achieved outstanding pico- and sub-picosecond pulsations covering the near-infrared (NIR) and visible spectral range in recent years. However, it has been a stagnant task for more than two decades to leapfrog into the sub-100 femtosecond (fs) regime as the Pr gain bandwidths are too narrow for their major transition lines. Although the wide tunability at the NIR bands in the Pr:YLF crystals has been explored, the spectral tails in these transitions suffer severely from weak gains for mode locking, combined with the intricate dispersion control to achieve transform-limit formation. In this work, we target the Pr:YLF’s 895-nm line with a specially designed edge-pass filter to balance the gain bandwidth and transitional strength. By deploying a symmetric dispersion scheme and tuning with the soft actor-critic artificial intelligence (AI) algorithm, we have achieved the pulse duration down to sub-100-fs in a Pr laser for the first time. This work also enriches the AI-assisted methodology for ultrafast solid-state laser realizations.
Vertically stacked quantum well diodes for multifunctional applications
Authors: Fu Jianwei , Fu Kang , Wang Binju , Ye Ziqi , Gao Xumin , Yan Jiabin , Wang Yongjin
Published: October 2023

Dual-functioning multiple quantum well (MQW) diodes can simultaneously transmit and receive information through visible light. Here, we report vertically stacked red, green, and blue (RGB) MQW diodes for light detection and display applications. Both blue and green MQW diodes are monolithically integrated with distributed Bragg reflector (DBR) filters to realize the separation of light. The versatile RGB MQW transmitter/receiver system not only creates full-color display but also effectively separates RGB light into various colors. These results open feasible routes to generate multifunctional device for the development of full-color display and light receiver.
High-repetition-rate pulse generation via self-sustaining cross-gain modulation in a semiconductor-based laser
Authors: Smirnov Sergey , Nyushkov Boris , Ivanenko Aleksey , Bednyakova Anastasia
Published: October 2023

We present a simple and efficient method for generating regular pulse trains with GHz pulse repetition rates in lasers based on semiconductor optical amplifiers (SOAs). This method enables pulse formation without active modulation or saturable absorption of the generated radiation. The method relies upon the self-sustaining cross-gain modulation which is achieved by adding the negative optical feedback (NOF) to a ring laser configuration. The resulting modulation of laser gain is shown to be restricted to the frequencies which match both the spacing of longitudinal laser modes and the highest peaks in the NOF-induced instability gain spectrum. This enables the reproducible stationary pulse generation at the strictly defined repetition rates. The feasibility of the method was confirmed by the stable generation of sub-nanosecond pulses at repetition rates up to 1.79 GHz in a SOA-based laser with a simple fiber cavity.
Prevalence of carbapenem-resistant and extended-spectrum beta-lactamase-producing Enterobacteriaceae in a teaching hospital in Ghana
Authors: Sampah James , Owusu-Frimpong Isaac , Aboagye Frank Twum , Owusu-Ofori Alex
Published: October 2023

Background

Carbapenem-resistant Enterobacteriaceae (CRE) and Extended-spectrum beta-lactamase (ESBL) production among Gram-negative Enterobacteriaceae is an increasing global challenge due to the high morbidity and mortality associated with their infections, especially in developing countries where there are little antibiotic treatment options. Despite these challenges, few studies in Ghana have described the burden of CRE. Therefore, this study aimed to determine the prevalence of carbapenem-resistant Enterobacteriaceae isolated from patients at the Cape Coast Teaching Hospital (CCTH) in the Central region of Ghana.

Methodology/Principal findings

Enterobacteriaceae isolates were collected from April to July 2019 at the bacteriology unit of CCTH using a consecutive sampling method. Isolates were identified by standard microbiological techniques and confirmed using API 20E. Kirby Bauer disc diffusion method was used to determine the antibiogram of isolates. Isolates were also subjected to ESBL testing using the single-disc combination method. Carbapenem-resistant isolates were identified by the Kirby Bauer disc diffusion method and then examined genotypically for the presence of blaKPC-1, blaIMP-1, blaVIM-1, blaNDM-1, and blaOXA-48 genes via polymerase chain reaction (PCR). Of the 230 isolates comprising E. coli (40.9%), Citrobacter spp. (32.6%), K. pneumoniae (9.1%), P. mirabilis (6.1%), P. vulgaris (5.2%), Enterobacter spp (3.5%)., K. oxytoca (2.2%), and Serratia marcenses (0.4%). Most isolates were from urine 162(70.4%) and wound samples. The isolates showed high resistance to ampicillin 171 (74.3%) and cefuroxime 134(58.3%). The prevalence of MDR was 35.2% (81), with E. coli 40(42.6%) being the majority that exhibited MDR. Of the 230 isolates, 113(49.1%) were ESBL producers, with E. coli 54(57.5%) accounting for the majority, while Serratia marcenses was the least. Of the 13 (5.7%) CRE isolates that showed resistance towards carbapenem in the disc diffusion method, 11 showed the presence of the blaNDM-1 gene, while all isolates showed the presence of the blaOXA-48 gene.

Conclusion

The prevalence of carbapenem resistance and ESBL-producing Enterobacteriaceae pathogens among patients at the Cape Coast Teaching Hospital is high and alarming. Therefore, it is imperative to consider effective infection prevention and control measures should be implemented at the hospital to prevent the rapid spread of these dangerous organisms.