bluuebunny/crossref_metadata_2025 huggingface dataset:
Sales Effort Management Under All-or-Nothing Constraint
Authors: Du Longyuan , Hu Ming , Wu Jiahua
Published: October 2021

We consider a sales effort management problem under an all-or-nothing constraint. The seller will receive no bonus/revenue if the sales volume fails to reach a predetermined target at the end of the sales horizon. Throughout the sales horizon, the sales process can be moderated by the seller through costly effort. We show that the optimal sales rate is nonmonotonic with respect to the remaining time or the outstanding sales volume required to reach the target. Generally, it has a watershed structure, such that for any needed sales volume, there exists a cutoff point on the remaining time above which the optimal sales rate decreases in the remaining time and below which it increases in the remaining time. We then study easy-to-compute heuristics that can be implemented efficiently. We start with a static heuristic derived from the deterministic analog of the stochastic problem. With an all-or-nothing constraint, we show that the performance of the static heuristic hinges on how the profit-maximizing rate fares against the target rate, which is defined as the sales target divided by the length of the sales horizon. When the profit-maximizing rate is higher than the target rate, the static heuristic adopting the optimal deterministic rate is asymptotically optimal with negligible loss. On the other hand, when the profit-maximizing rate is lower than the target rate, the performance loss of any asymptotically optimal static heuristic is of an order greater than the square root of the scale parameter. To address the poor performance of the static heuristic in the latter case, we propose a modified resolving heuristic and show that it is asymptotically optimal and achieves a logarithmic performance loss.

This paper was accepted by Gabriel Weintraub, revenue management and market analytics.
Channel Structures of Online Retail Platforms
Authors: Ha Albert Y. , Tong Shilu , Wang Yunjie
Published: October 2021

Problem definition: This paper investigates the channel choice problem of an online platform that exerts service effort to enhance the demand in its sales channels. Academic/practical relevance: In the existing literature on the channel structure of an online retail platform, it is usually assumed that a manufacturer sells through either the platform’s agency or reselling channel but not both. In practice, many manufacturers sell the same products through both channels of the same online retail platform, a phenomenon that cannot be explained by the existing theory. Moreover, online retail platforms routinely invest in retail services that enhance the demand in their sales channels. Methodology: We develop a game-theoretic model to investigate the equilibrium channel choice, wholesale price, and retail quantity decisions. We also conduct sensitivity analysis to evaluate the impact of some parameters on the equilibrium. Results: We derive conditions under which each of the three channel structures (agency channel, reselling channel, and dual channel) emerges in equilibrium. We show that the wholesale price in the reselling channel is reduced because of the addition of the agency channel even when both channels are equally efficient, which extends the wholesale price effect because of the addition of a less efficient direct channel in the supplier encroachment literature. Our analysis highlights the flexibility of a dual channel for firms to shift sales between the two channels, which could increase the retail platform’s incentive to exert service effort. Managerial implications: Our study provides useful insights to managers to understand and make channel choice decisions in supply chains with manufacturers selling through online retail platforms.
Where Do Born Globals Come from? A Neoconfigurational Institutional Theory
Authors: Fainshmidt Stav , Smith Adam W. , Aguilera Ruth V.
Published: October 2021

Born globals, recently established firms that obtain a substantial share of their revenue from foreign markets, can help strengthen countries’ economic vitality and increase innovation levels. The extent of born global formation varies considerably across countries, yet it is unclear why this is the case. Drawing on the neoconfigurational institutional perspective, we develop a typology of institutional contexts associated with high born global formation rates. We posit that high rates of born global formation occur where institutional features favorable to border-spanning activities complement institutional features conducive to entrepreneurial activity, thus forming an institutional configuration that enables, equips, and motivates more societal members to launch born globals. Accordingly, we hypothesize a primary institutional configuration where international transaction facilitators, entrepreneurial educational capital, and entrepreneurial norms combine to propel born global formation. Further, we draw on the internationalization literature to propose two alternative types of institutional configurations conducive to born global formation. These two types provide functional substitutes for the primary type and are distinctly propelled by (1) escapism from low-quality public governance institutions or (2) immigrant entrepreneurship. Fuzzy-set qualitative comparative analysis on data from 66 countries supports our typology and illustrates why born global activity may thrive even in contexts with institutional weaknesses. Our study develops a neoconfigurational model to advance a holistic understanding of the born global phenomenon’s theoretical drivers, contributing to research on comparative capitalism and international entrepreneurship.
Service Ecosystem Health: A Transformative Approach to Elevating Service Science
Authors: Fisk Raymond P. , Alkire Linda
Published: October 2021

Events in the year 2020 threw human service systems into chaotic states, threatening peoples’ lives and livelihoods. Before 2020, there were many profound challenges to human life that had been well documented by efforts such as the United Nations Sustainable Development Goals. The COVID-19 pandemic seems to be a “last straw” crisis that has destabilized modern human civilization. This article diagnoses various crises of human service systems (e.g., COVID-19, inequality, and climate change) and proposes the metaphor of service ecosystem health for reimagining service science in a postpandemic world. Service ecosystem health is defined as the interdependent state of private, public, and planetary well-being necessary for sustaining life. This article reimagines service science, broadens transformative service research, builds the service ecosystem health metaphor, outlines the Goldilocks Civilization thought experiment, and explores designing for a Goldilocks civilization. Because service is for humans, the ultimate objective is to elevate service science to uplift human well-being.
Prescribing considerations in the use of oral medication in Parkinson's disease
Authors: Price Jane , Martin Hannah , Ebenezer Louise
Published: October 2021

The aim of this article is to consider and support the rationale for prescribing decisions throughout the Parkinson's disease trajectory. The authors will discuss the challenges of managing both motor and non-motor features of Parkinson's disease mindful of potential complications attributable to both progression and medications used. This will include motor fluctuations and impulse control behaviours, which can adversely affect quality of life. The Parkinson's specialist will need to consider a treatment regimen that optimises symptom control while limiting the potential adverse effects of medications. This article will provide an overview of oral medications used throughout the recognised stages of Parkinson's disease.
Angular distribution of photon density waves radiance in media with different scattering anisotropy
Authors: Luchinin Alexander G. , Kirillin Mikhail Yu.
Published: October 2021

Statistical modeling of pulsed frequency responses of the light field radiance by an isotropic point source was performed by Monte Carlo technique. Scattering properties of the medium were simulated by the Henyey–Greenstein phase function with different anisotropy factor values. Angular distributions of the pulsed field and amplitudes of the photon density waves in a certain range of parameters were shown to have a qualitatively different character for media with quasi-isotropic and strongly anisotropic scattering. A comparison of the impulse and frequency characteristics was performed for media with strongly anisotropic scattering with different scattering phase functions yet the same anisotropy factor. The main difference in the angular distributions of the fields is observed in the rear hemisphere.
Electric-field-assisted resonance scanning spectroscopy based on a graphene-on-silicon dual-mode microring
Authors: Han Senmiao , Chen Weicehng , Hu Haofeng , Cheng Zhenzhou , Liu Tiegen
Published: October 2021

Mid-infrared (mid-IR) microring resonators (MRRs) have been extensively studied for biochemical sensing. However, the temperature fluctuation is an undesirable cross-sensitive effect for refractive index (RI) sensing. Here, we study an electric-field-assisted resonance scanning (EARS) spectroscopic technique based on a graphene-on-silicon dual-mode MRR to overcome this limitation. Specifically, based on the proposed method, we theoretically achieved a RI measuring error of only 2% under a temperature fluctuation of 1 K, which is improved by a factor of ten compared with a single-mode MRR. Moreover, a single-wavelength mid-IR laser is utilized in the technique, significantly simplifying the characterization setup. Also, we discuss the limit of detection and range of measurement of the EARS technique. Our study paves a promising way of developing monolithically chip-integrated mid-IR sensing devices.
Sub-Rayleigh characterization of a binary source by spatially demultiplexed coherent detection
Authors: Datta Chandan , Len Yink Loong , Łukanowski Karol , Banaszek Konrad , Jarzyna Marcin
Published: October 2021

We investigate theoretically coherent detection implemented simultaneously on a set of mutually orthogonal spatial modes in the image plane as a method to characterize properties of a composite thermal source below the Rayleigh limit. A general relation between the intensity distribution in the source plane and the covariance matrix for the complex field amplitudes measured in the image plane is derived. An algorithm to estimate parameters of a two-dimensional symmetric binary source is devised and verified using Monte Carlo simulations to provide super-resolving capability for a high ratio of signal to detection noise (SNR). Specifically, the separation between two point sources can be meaningfully determined down to SNR−1/2 in the length unit determined by the spatial spread of the transfer function of the imaging system. The presented algorithm is shown to make a nearly optimal use of the measured data in the sub-Rayleigh region.
Time-accuracy imaging quality prediction method for an infrared detection system under hypersonic conditions
Authors: Ju Lin , Liu Yinglun , Ming Yue , Shi Xiaotian , Li Xueshen , Fan Zhigang
Published: October 2021

The imaging quality of infrared detection systems over time directly affects their ability to track targets accurately. In this study, a prediction scheme for the image quality of infrared detection system under hypersonic conditions based on time accuracy has been developed. Further, based on the time discretization, a calculation model has been established for the prediction scheme to perform numerical simulation. In particular, for verifying the reliability of this prediction method and the associated numerical calculation model, a comparison has been made between the numerical simulation results and the wind tunnel test results. The maximum error of the comparison result is less than 4.5%, and the reliability of the method proposed in this paper has been proved.
Multipole-phase division multiplexing
Authors: Ruffato Gianluca , Grillo Vincenzo , Romanato Filippo
Published: October 2021

The control of structured waves has recently opened innovative scenarios in the perspective of radiation propagation, advanced imaging, and light-matter interaction. In information and communication technology, the spatial degrees of freedom offer a wider state space to carry many channels on the same frequency or increase the dimensionality of quantum protocols. However, spatial decomposition is much more arduous than polarization or frequency multiplexing, and very few practical examples exist. Among all, beams carrying orbital angular momentum gained a preeminent role, igniting a variety of methods and techniques to generate, tailor, and measure that property. In a more general insight into structured-phase beams, we introduce here a new family of wave fields having a multipole phase. These beams are devoid of phase singularities and described by two continuous spatial parameters which can be controlled in a practical and compact way via conformal optics. The outlined framework encompasses multiplexing, propagation, and demultiplexing as a whole for the first time, describing the evolution and transformation of wave fields in terms of conformal mappings. With its potentialities, versatility, and ease of implementation, this new paradigm introduces a novel playground for space division multiplexing, suggesting unconventional solutions for light processing and free-space communications.
Model for estimating the astronomical seeing at Dome A, Antarctica
Authors: Yang Qike , Wu Xiaoqing , Han Yajuan , Qing Chun , Wu Su , Su Changdong , Wu Pengfei , Zhang Shitai
Published: October 2021

A model for estimating astronomical seeing at Kunlun Station (Dome A, Antarctica) is proposed. This model is based on the Tatarskii equation, using the wind shear and temperature gradient as inputs, and a seeing model depending directly on the weather data is provided. The seeing and near-ground weather data to build and validate the proposed seeing model were measured at Dome A during the summer of 2019. Two calculation methods were tested from the measured weather data relating the wind shear and temperature gradient to a combination of the two levels for the boundary layer. Both methods performed well, with correlation coefficients higher than 0.77. The model can capture the main seeing trends in which the seeing becomes small when weak wind speed and strong temperature inversion occur inside the boundary layer.
Optical signal detection in turbid water using multidimensional integral imaging with deep learning
Authors: Krishnan Gokul , Joshi Rakesh , O’Connor Timothy , Javidi Bahram
Published: October 2021

Optical signal detection in turbid and occluded environments is a challenging task due to the light scattering and beam attenuation inside the medium. Three-dimensional (3D) integral imaging is an imaging approach which integrates two-dimensional images from multiple perspectives and has proved to be useful for challenging conditions such as occlusion and turbidity. In this manuscript, we present an approach for the detection of optical signals in turbid water and occluded environments using multidimensional integral imaging employing temporal encoding with deep learning. In our experiments, an optical signal is temporally encoded with gold code and transmitted through turbid water via a light-emitting diode (LED). A camera array captures videos of the optical signals from multiple perspectives and performs the 3D signal reconstruction of temporal signal. The convolutional neural network-based bidirectional Long Short-Term Network (CNN-BiLSTM) network is trained with clear water video sequences to perform classification on the binary transmitted signal. The testing data was collected in turbid water scenes with partial signal occlusion, and a sliding window with CNN-BiLSTM-based classification was performed on the reconstructed 3D video data to detect the encoded binary data sequence. The proposed approach is compared to previously presented correlation-based detection models. Furthermore, we compare 3D integral imaging to conventional two-dimensional (2D) imaging for signal detection using the proposed deep learning strategy. The experimental results using the proposed approach show that the multidimensional integral imaging-based methodology significantly outperforms the previously reported approaches and conventional 2D sensing-based methods. To the best of our knowledge, this is the first report on underwater signal detection using multidimensional integral imaging with deep neural networks.
Improving few-photon optomechanical effects with coherent feedback
Authors: Wei Yue , Wang Xiaojuan , Xiong Biao , Zhao Chengsong , Liu Jibing , Shan Chuanjia
Published: October 2021

Few-photon effects such as photon blockade and tunneling have potential applications in modern quantum technology. To enhance the few-photon effects in an optomechanical system, we introduce a coherent feedback loop to cavity mode theoretically. By studying the second-order correlation function, we show that the photon blockade effect can be improved with feedback. Under appropriate parameters, the photon blockade effect exists even when cavity decay rate is larger than the single-photon optomechanical coupling coefficient, which may reduce the difficulty of realizing single-photon source in experiments. Through further study of the third-order correlation function, we show that the tunneling effect can also be enhanced by feedback. In addition, we discuss the application of feedback on Schrödinger-cat state generation in an optomechanical system. The result shows that the fidelity of cat state generation can be improved in the presence of feedback loop.
Tomographic absorption spectroscopy based on dictionary learning
Authors: Shui Chongyuan , Huang Jianqing , Liu Hecong , Cai Weiwei , Sanders Scott T.
Published: October 2021

Tomographic absorption spectroscopy (TAS) has an advantage over other optical imaging methods for practical combustor diagnostics: optical access is needed in a single plane only, and the access can be limited. However, practical TAS often suffers from limited projection data. In these cases, priors such as smoothness and sparseness can be incorporated to mitigate the ill-posedness of the inversion problem. This work investigates use of dictionary learning (DL) to effectively extract useful a priori information from the existing dataset and incorporate it in the reconstruction process to improve accuracy. We developed two DL algorithms; our numerical results suggest that they can outperform classical Tikhonov reconstruction under moderate noise conditions. Further testing with experimental data indicates that they can effectively suppress reconstruction artifacts and obtain more physically plausible solutions compared with the inverse Radon transform.
Picosecond ultrasonics with a free-running dual-comb laser
Authors: Pupeikis Justinas , Willenberg Benjamin , Bruno Francois , Hettich Mike , Nussbaum-Lapping Alexander , Golling Matthias , Bauer Carolin P. , Camenzind Sandro L. , Benayad Abdelmjid , Camy Patrice , Audoin Bertrand , Phillips Christopher R. , Keller Ursula
Published: October 2021

We present a free-running 80-MHz dual-comb polarization-multiplexed solid-state laser which delivers 1.8 W of average power with 110-fs pulse duration per comb. With a high-sensitivity pump-probe setup, we apply this free-running dual-comb laser to picosecond ultrasonic measurements. The ultrasonic signatures in a semiconductor multi-quantum-well structure originating from the quantum wells and superlattice regions are revealed and discussed. We further demonstrate ultrasonic measurements on a thin-film metalized sample and compare these measurements to ones obtained with a pair of locked femtosecond lasers. Our data show that a free-running dual-comb laser is well-suited for picosecond ultrasonic measurements and thus it offers a significant reduction in complexity and cost for this widely adopted non-destructive testing technique.
Tunable frequency matching for efficient four-wave-mixing Bragg scattering in microrings
Authors: Liu JiaCheng , Zheng Qilin , Xia GongYu , Wu Chao , Zhu ZhiHong , Xu Ping
Published: October 2021

We propose and theoretically study a tunable frequency matching method for four-wave-mixing Bragg-scattering frequency conversion in microring resonators. A tunable coupling between the clockwise and counterclockwise propagating modes in the resonators was designed to introduce adjustable mode splitting, thus compensating for the frequency mismatching under different wavelengths. Using a silicon nitride ring resonator as an example, we showed that the tuning bandwidth approaches 35 number of FSRs. Numerical simulations further revealed that the phase-matching strategy is valid under different wavelength combinations and is robust to variations in waveguide geometry and fabrication. These results suggest promising applications in high-efficiency frequency conversion, integrated nonlinear photonics, and quantum optics.
Asymmetrical bidirectional VLC based on beam homogenizer OAM generation technology
Authors: Chou Hsi-Hsir , Liu Kang-Yun
Published: October 2021

An asymmetric bidirectional visible light communication (B-VLC) system is presented in this Letter. It combines beam homogenizers with a spatial light modulator (SLM) to implement the orbital angular momentum (OAM) generation technology at a terminal user for uplink data transmission. The major advantage of the proposed approach is that multiple OAM modes can be arbitrarily generated simultaneously by a single SLM. The uplink transmission capacity can also be significantly improved by multiplexing more generated OAM channels. For the proof of concept, an asymmetric B-VLC based on the OAM generation technology for uplink transmission at a distance of nearly 2 m has been implemented. The baseband modulation schemes, including on-off keying (OOK) and quadrature phase-shift keying, were also implemented to validate the transmission performance. The experimental results show that the downlink transmission capacity of up to 2.2 Gbit/s can be achieved using an

S

-polarization beam. In comparison, the uplink transmission capacity can also be significantly enhanced by using

P

-polarization through multiplexing four OAM channels, each with a maximum transmission rate of up to 800 Mbit/s. The bit error rates (BERs) of both uplink and downlink transmissions were all under the forward error correction limit (

B
E
R

=

3

×

10

−
3

).
Power-over-fiber in a 10  km long multicore fiber link within a 5G fronthaul scenario
Authors: López-Cardona J. D. , Rommel S. , Grivas E. , S. Montero D. , Dubov M. , Kritharidis D. , Tafur-Monroy I. , Vázquez C.
Published: October 2021

We evaluate the impact of Power-over-Fiber (PoF) technology on the
fronthaul of a 5G-NR network with an Analog-Radio-over-Fiber at
25.5 GHz on a 10 km long multicore fiber. The study in this Letter
analyzes the bit error rate (BER) performance for different levels of
energy transmitted by the PoF system. 133 mW of maximum optical power
at reception is demonstrated showing negligible BER impact or data
transmission BER improvement in a dedicated and shared scenario.
Signal estimation and coherence
Authors: Ares Laura , Luis Alfredo
Published: October 2021

We address the relation between quantum metrological resolution and quantum coherence. We develop a quantum version of the Wiener–Khintchine theorem for a suitable model of a quantum ruler, putting the contributions of the probe and measurement on equal footing. We illustrate this approach with several examples of linear metrology.
Polymer/silica hybrid waveguide amplifier at 532  nm based on NaYF4:Er3+, Yb3+ nanocrystals
Authors: Sun Tonghe , Fu Yuewu , Cao Zhigeng , Tao Siliang , Yan Jinming , Zhao Dan , Zhang Dan , Wang Fei , Zhang Daming
Published: October 2021

An optical waveguide amplifier, which can solve the problem of optical attenuation in optical network transmission, is the key technology to solve optical chip integration and optical interconnection. Here, to the best of our knowledge, we propose a novel polymer/silica hybrid waveguide amplifier at 532 nm for the first time. The research is of great significance to the improvement of short distance communication and visible light communication system. The waveguide amplifier was designed as an embedded structure based on

N
a
Y
F

4

:

E
r

3
+

Y
b

3
+

nanocrystals, which were synthesized by high-temperature thermal decomposition. When the input signal power was 0.1 mW, and the pump power was 300 mW, a relative gain of 4.3 dB was obtained on an 8 mm waveguide. This result is of great research significance to break the distance limit and make all-optical transmission a reality.
Invisible Mie scatterer
Authors: Zheng Kanpei , Zhang Zhanyuan , Qin Feifei , Xu Yi
Published: October 2021

Dielectric Mie scatterers possessing simultaneously magnetic and electric resonances can be used to tailor scattering utilizing the interference among electromagnetic multipole moments. Cloaking for this type of Mie scatterer is important for various applications. However, the existing cloaking mechanisms mainly focus on the elimination of net electric dipole moments, which have not been generalized to a Mie scatterer with both magnetic and electric responses yet. Herein, we propose and experimentally demonstrate an invisible Mie scatterer utilizing a hybrid skin cloak. The hybrid mechanism relies on the realization of a magnetic analog of a plasmonic cloak and the electric anapole condition to eliminate the net magnetic and electric dipole moments simultaneously. Microwave experiments are provided to validate the proposal. Our results not only introduce a new concept of skin cloaking for electromagnetic scatterers, but also provide new insight for the invisibility and illusion of Mie scatterers.
Twist and strain tuning of third harmonic generation in glass nanostrand with two sub-wavelength hollow channels
Authors: Chen Y. , Hammer J. , Joly N. Y. , Russell P. St.J.
Published: October 2021

A major challenge in third harmonic generation and its converse, parametric down-conversion, is how to arrange phase matching between signals at

ω

and

3

ω

while maintaining a high nonlinear overlap. In this Letter, we present a design consisting of a nanostrand of glass with two hollow channels. The fundamental and third harmonic modal fields, enhanced in the region between the channels, have high nonlinear overlap, while the phase-matching wavelength can be coarse-tuned by gas pressure and fine-tuned by axial strain and mechanical twist, which, remarkably, have opposite effects. The ability to adjust the phase-matching condition may facilitate efficient generation of entangled photon triplets.
The invasive pathogen Yersinia pestis disrupts host blood vasculature to spread and provoke hemorrhages
Authors: Mikaty Guillain , Coullon Héloïse , Fiette Laurence , Pizarro-Cerdá Javier , Carniel Elisabeth
Published: October 2021

Yersinia pestis is a powerful pathogen with a rare invasive capacity. After a flea bite, the plague bacillus can reach the bloodstream in a matter of days giving way to invade the whole organism reaching all organs and provoking disseminated hemorrhages. However, the mechanisms used by this bacterium to cross and disrupt the endothelial vascular barrier remain poorly understood. In this study, an innovative model of in vivo infection was used to focus on the interaction between Y. pestis and its host vascular system. In the draining lymph nodes and in secondary organs, bacteria provoked the porosity and disruption of blood vessels. An in vitro model of endothelial barrier showed a role in this phenotype for the pYV/pCD1 plasmid that carries a Type Three Secretion System. This work supports that the pYV/pCD1 plasmid is responsible for the powerful tissue invasiveness capacity of the plague bacillus and the hemorrhagic features of plague.
Prevalence of bacteriologically confirmed pulmonary tuberculosis and associated risk factors: A community survey in Thirvallur District, south India
Authors: Dolla Chandra Kumar , Dhanaraj Bhaskaran , Chandrasekaran Padmapriyadarsini , Selvaraj Sriram , Menon Pradeep Aravindan , Thiruvengadam Kannan , Krishnan Rajendran , Mondal Rajesh , Malaisamy Muniyandi , Marinaik Srinivasa B. , Murali Lakshmi , Tripathy Srikanth Prasad
Published: October 2021

Background

Tuberculosis (TB) prevalence surveys add to the active case detection in the community level burden of TB both national and regional levels. The aim of this study was to assess the prevalence of bacteriologically confirmed pulmonary tuberculosis (PTB) in the community.

Methods

Household community-based tuberculosis disease survey was conducted targeting 69054 population from 43 villages of 5 blocks in Tiruvallure district adopting cluster sampling methodology of ≥15 years old adult rural population of South India during 2015–2018. All eligible individuals with suspected symptoms of PTB were screened with chest X-ray. Two sputum specimens (one spot and the other early morning sample) were collected for M.tb smear and culture examination. Conversely demographical, smoking and alcohol drinking habits information were also collected to explore the risk factor. Stepwise logistic regression was employed to associate risk factors for PTB.

Results

A total of 62494 were screened among 69054 eligible population, of whom 6340 were eligible for sputum specimen collection. Sputum for M.tb smear and culture examination were collected in 93% of participants. The derived prevalence of PTB was 307/100000 population (smear-positive 130; culture positive 277). As expected that PTB has decreased substantially compared to preceding surveys and it showed that older age, male, low BMI, diabetes, earlier history of TB and alcohol users were significantly associated (p < .0001) with an increased risk of developing PTB.

Conclusion

Upshot of the active survey has established a reduction in the prevalence of PTB in the rural area which can be accredited to better programmatic implementation and success of the National TB Control Programme in this district. It also has highlighted the need for risk reduction interventions accelerate faster elimination of TB.
Polo-like kinase 2 inhibition reduces serine-129 phosphorylation of physiological nuclear alpha-synuclein but not of the aggregated alpha-synuclein
Authors: Elfarrash Sara , Jensen Nanna Møller , Ferreira Nelson , Schmidt Sissel Ida , Gregersen Emil , Vestergaard Marie Vibeke , Nabavi Sadegh , Meyer Morten , Jensen Poul Henning
Published: October 2021

Accumulation of aggregated alpha-synuclein (α-syn) is believed to play a pivotal role in the pathophysiology of Parkinson’s disease (PD) and other synucleinopathies. As a key constituent of Lewy pathology, more than 90% of α-syn in Lewy bodies is phosphorylated at serine-129 (pS129) and hence, it is used extensively as a marker for α-syn pathology. However, the exact role of pS129 remains controversial and the kinase(s) responsible for the phosphorylation have yet to be determined. In this study, we investigated the effect of Polo-like kinase 2 (PLK2) inhibition on formation of pS129 using an ex vivo organotypic brain slice model of synucleinopathy. Our data demonstrated that PLK2 inhibition has no effect on α-syn aggregation, pS129 or inter-neuronal spreading of the aggregated α-syn seen in the organotypic slices. Instead, PLK2 inhibition reduced the soluble pS129 level in the nuclei. The same finding was replicated in an in vivo mouse model of templated α-syn aggregation and in human dopaminergic neurons, suggesting that PLK2 is more likely to be involved in S129-phosphorylation of the soluble physiological fraction of α-syn. We also demonstrated that reduction of nuclear pS129 following PLK2 inhibition for a short time before sample collection improves the signal-to-noise ratio when quantifying pS129 aggregate pathology.
Assessment of knowledge, attitude and practice toward COVID-19 and associated factors among health care workers in Silte Zone, Southern Ethiopia
Authors: Yesse Mubarek , Muze Mohammed , Kedir Shemsu , Argaw Bedru , Dengo Mohammed , Nesre Tajudin , Hamdalla Faris , Saliha Awol , Mussa Tofik , Kasim India , Kedir Abdulfeta , Delebo Tofik , Sunkemo Awol , Badeg Yesuf , Ensarmu Dureti , Abebe Dereje , Dessalegn Amara , Ayelign Henok
Published: October 2021

Introduction

COVID-19 is a pandemic respiratory disease caused by the highly contagious novel coronavirus (SARS-CoV 2). The disease is now quickly spreading around the world, resulting in ongoing coronavirus pandemic. Healthcare workers are more susceptible to COVID-19 infection than the general population due to frequent contact with infected individuals.

Objective

This study was aimed to assess knowledge, attitude and practice towards COVID-19 and associated factors among health care workers.

Methods

Facility-based cross-sectional study design was conducted among health care workers in Silte Zone. A total of 379 health professionals were selected using multistage stratified sampling technique. Self-administered questionnaire was used to collect data. Binary logistic regression model was used to see association between outcome and independent variables.

Results

This study found 74.9%, 84.2% and 68.9% prevalence of adequate knowledge, positive attitude and good practice respectively. Working in comprehensive specialized hospital (AOR = 4.46, 95% CI = 1.46–13.62).having MSC degree (AOR = 10.26, 95% CI = 2.27–46.44), and training on COVID-19 (AOR = 6.59, 95% CI = 2.97–14.65) were strongly associated with knowledge of health care workers. On the other hand, older age (AOR = 3.35, 95% CI = 1.07–10.50), training on COVID-19 (AOR = 3.73, 95% CI = 1.82–7.63), Work experience (AOR = 3.78, 95% CI = 1.46–9.80) and Knowledge (AOR = 5.45, 95% CI = 2.60–11.43) were significantly associated with attitude, whereas source of information from friends or colleagues (AOR = 3.13, 95% CI = 1.28–7.66), working in primary hospital (AOR = 0.36, 95% CI = 0.21–0.620) and having good knowledge (AOR = 1.80, 95% CI = 1.03–3.14) were strongly associated with good practice of health care workers.

Conclusion

This study found majority of health care workers had good level of knowledge and positive attitude toward COVID-19, but lower proportion of health care workers practices sufficiently in the study area. Type of health facilities, level of education, training on COVID-19, work experience, type of source of information were significantly associated with knowledge, attitude and practice of health care workers. Stakeholders need to focus on interventions that increase preventive practices of health care workers.
A comparison of self-report, systematic observation and third-party judgments of church attendance in a rural Fijian Village
Authors: Shaver John H. , White Thomas A. J. , Vakaoti Patrick , Lang Martin
Published: October 2021

Social desirability reporting leads to over estimations of church attendance. To date, researchers have treated over-reporting of church attendance as a general phenomenon, and have been unable to determine the demographic correlates of inaccuracy in these self-reports. By comparing over eight months of observational data on church attendance (n = 48 services) to self-report in a rural Fijian village, we find that 1) self-report does not reliably predict observed attendance, 2) women with two or more children (≥ 2) are more likely to over-report their attendance than women with fewer children (≤ 1), and 3) self-report of religiosity more reliably predicts observed church attendance than does self-report of church attendance. Further, we find that third-party judgements of church attendance by fellow villagers are more reliably associated with observed church attendance than self-report. Our findings suggest that researchers interested in estimating behavioral variation, particularly in domains susceptible to social desirability effects, should consider developing and employing third-party methods to mitigate biases inherent to self-report.
Phyto-ecological studies and distribution pattern of plant species and communities of Dhirkot, Azad Jammu and Kashmir, Pakistan
Authors: Mumshad Mevish , Ahmad Israr , Khan Shujaul Mulk , Abdullah  , Rehman Khadija , Islam Mohammad , Sakhi Shazia , Khan Sami Ullah , Afridi Sahib Gul , Shams Sulaiman , Azam Samana , Ahmad Ishtiaq , Afza Rabia , Ahmad Zeeshan
Published: October 2021

Plant species represent the hierarchical expression of vegetation as it is affected by various environmental gradients. We explored the plant species composition, distribution pattern, communities formation and their respective indicators under the influence of various environmental factors in the Dhirkot region, Azad Jammu and Kashmir. It was hypothesized that different environmental factors were responsible for the formation of various plant communities each with a distinct indicator. Quantitative ecological techniques were used for the sampling of vegetation. A total of 114 quadrats were established in 13 selected sampling sites. Phytosociological attributes were calculated for each plant species at each quadrat. Soil samples were collected and analyzed using different standard protocols. All the collected data were analyzed using Cluster Analysis, Indicator Species Analysis and Canonical Correspondence Analysis of PCORD and CANOCO software, respectively. A total of 145 plant species were recorded belong to 62 different families. Asteraceae and Lamiaceae were the dominant families, represented by 12 species each (8.27%). Cluster Analysis classify all the stations and plants into four major plant communities as 1) Olea-Desmodium-Prunilla community. 2) Abies-Zanthoxylum-Pteracanthus community 3) Cedrus-Elaeagnus-Hypericum community 4) Alnus-Myrsine–Ranunculus community. Soil pH, electrical conductivity, soil saturation, organic matter and altitude were the significant environmental factors that play its essential role in the plant species distribution, composition, formation of major plant communities and their respective indicators in the region. It is recommended that the identified indicator and rare plant species of the investigated area can further be grown for conservation and management purposes in in-situ environment.
Divergence of bacterial communities in the lower airways of CF patients in early childhood
Authors: O’Connor John B. , Mottlowitz Madison M. , Wagner Brandie D. , Boyne Kathleen L. , Stevens Mark J. , Robertson Charles E. , Harris Jonathan K. , Laguna Theresa A.
Published: October 2021

Rationale

Chronic airway infection and inflammation resulting in progressive, obstructive lung disease is the leading cause of morbidity and mortality in cystic fibrosis. Understanding the lower airway microbiota across the ages can provide valuable insight and potential therapeutic targets.

Objectives

To characterize and compare the lower airway microbiota in cystic fibrosis and disease control subjects across the pediatric age spectrum.

Methods

Bronchoalveolar lavage fluid samples from 191 subjects (63 with cystic fibrosis) aged 0 to 21 years were collected along with relevant clinical data. We measured total bacterial load using quantitative polymerase chain reaction and performed 16S rRNA gene sequencing to characterize bacterial communities with species-level sensitivity for select genera. Clinical comparisons were investigated.

Measurements and main results

Cystic fibrosis samples had higher total bacterial load and lower microbial diversity, with a divergence from disease controls around 2–5 years of age, as well as higher neutrophilic inflammation relative to bacterial burden. Cystic fibrosis samples had increased abundance of traditional cystic fibrosis pathogens and decreased abundance of the Streptococcus mitis species group in older subjects. Interestingly, increased diversity in the heterogeneous disease controls was independent of diagnosis and indication. Sequencing was more sensitive than culture, and antibiotic exposure was more common in disease controls, which showed a negative relationship with load and neutrophilic inflammation.

Conclusions

Analysis of lower airway samples from people with cystic fibrosis and disease controls across the ages revealed key differences in airway microbiota and inflammation. The divergence in subjects during early childhood may represent a window of opportunity for intervention and additional study.
Condensed trajectory of the temporal correlation of diseases and mortality extracted from over 300,000 patients in hospitals
Authors: Paik Hyojung , Kim Jimin
Published: October 2021

Understanding mortality, derived from debilitations consisting of multiple diseases, is crucial for patient stratification. Here, in systematic fashion, we report comprehensive mortality data that map the temporal correlation of diseases that tend toward deaths in hospitals. We used a mortality trajectory model that represents the temporal ordering of disease appearance, with strong correlations, that terminated in fatal outcomes from one initial diagnosis in a set of patients throughout multiple admissions. Based on longitudinal healthcare records of 10.4 million patients from over 350 hospitals, we profiled 300 mortality trajectories, starting from 118 diseases, in 311,309 patients. Three-quarters (75%) of 59,794 end-stage patients and their deaths accrued throughout 160,360 multiple disease appearances in a short-term period (<4 years, 3.5 diseases per patient). This overlooked and substantial heterogeneity of disease patients and outcomes in the real world is unraveled in our trajectory map at the disease-wide level. For example, the converged dead-end in our trajectory map presents an extreme diversity of sepsis patients based on 43 prior diseases, including lymphoma and cardiac diseases. The trajectories involving the largest number of deaths for each age group highlight the essential predisposing diseases, such as acute myocardial infarction and liver cirrhosis, which lead to over 14,000 deaths. In conclusion, the deciphering of the debilitation processes of patients, consisting of the temporal correlations of diseases that tend towards hospital death at a population-wide level is feasible.
Effects of prebiotic oligofructose-enriched inulin on gut-derived uremic toxins and disease progression in rats with adenine-induced chronic kidney disease
Authors: Melekoglu Ebru , Cetinkaya M. Alper , Kepekci-Tekkeli S. Evrim , Kul Oguz , Samur Gulhan
Published: October 2021

Recent studies suggest that dysbiosis in chronic kidney disease (CKD) increases gut-derived uremic toxins (GDUT) generation, leads to systemic inflammation, reactive oxygen species generation, and poor prognosis. This study aimed to investigate the effect of oligofructose-enriched inulin supplementation on GDUT levels, inflammatory and antioxidant parameters, renal damage, and intestinal barrier function in adenine-induced CKD rats. Male Sprague-Dawley rats were divided into control group (CTL, n = 12) fed with standard diet; and CKD group (n = 16) given adenine (200 mg/kg/day) by oral gavage for 3-weeks to induce CKD. At the 4th week, CKD rats were subdivided into prebiotic supplementation (5g/kg/day) for four consecutive weeks (CKD-Pre, n = 8). Also, the control group was subdivided into two subgroups; prebiotic supplemented (CTL-Pre, n = 6) and non-supplemented group (CTL, n = 6). Results showed that prebiotic oligofructose-enriched inulin supplementation did not significantly reduce serum indoxyl sulfate (IS) but did significantly reduce serum p-Cresyl sulfate (PCS) (p = 0.002) in CKD rats. Prebiotic supplementation also reduced serum urea (p = 0.008) and interleukin (IL)-6 levels (p = 0.001), ameliorated renal injury, and enhanced antioxidant enzyme activity of glutathione peroxidase (GPx) (p = 0.002) and superoxide dismutase (SOD) (p = 0.001) in renal tissues of CKD rats. No significant changes were observed in colonic epithelial tight junction proteins claudin-1 and occludin in the CKD-Pre group. In adenine-induced CKD rats, oligofructose-enriched inulin supplementation resulted in a reduction in serum urea and PCS levels, enhancement of the antioxidant activity in the renal tissues, and retardation of the disease progression.
Behavioral alterations in long-term Toxoplasma gondii infection of C57BL/6 mice are associated with neuroinflammation and disruption of the blood brain barrier
Authors: Castaño Barrios Leda , Da Silva Pinheiro Ana Paula , Gibaldi Daniel , Silva Andrea Alice , Machado Rodrigues e Silva Patrícia , Roffê Ester , da Costa Santiago Helton , Tostes Gazzinelli Ricardo , Mineo José Roberto , Silva Neide Maria , Lannes-Vieira Joseli
Published: October 2021

The Apicomplexa protozoanToxoplasma gondiiis a mandatory intracellular parasite and the causative agent of toxoplasmosis. This illness is of medical importance due to its high prevalence worldwide and may cause neurological alterations in immunocompromised persons. In chronically infected immunocompetent individuals, this parasite forms tissue cysts mainly in the brain. In addition,T.gondiiinfection has been related to mental illnesses such as schizophrenia, bipolar disorder, depression, obsessive-compulsive disorder, as well as mood, personality, and other behavioral changes. In the present study, we evaluated the kinetics of behavioral alterations in a model of chronic infection, assessing anxiety, depression and exploratory behavior, and their relationship with neuroinflammation and parasite cysts in brain tissue areas, blood-brain-barrier (BBB) integrity, and cytokine status in the brain and serum. Adult female C57BL/6 mice were infected by gavage with 5 cysts of the ME-49 type IIT.gondiistrain, and analyzed as independent groups at 30, 60 and 90 days postinfection (dpi). Anxiety, depressive-like behavior, and hyperactivity were detected in the early (30 dpi) and long-term (60 and 90 dpi) chronicT.gondiiinfection, in a direct association with the presence of parasite cysts and neuroinflammation, independently of the brain tissue areas, and linked to BBB disruption. These behavioral alterations paralleled the upregulation of expression of tumor necrosis factor (TNF) and CC-chemokines (CCL2/MCP-1, CCL3/MIP-1α, CCL4/MIP-1β and CCL5/RANTES) in the brain tissue. In addition, increased levels of interferon-gamma (IFNγ), TNF and CCL2/MCP-1 were detected in the peripheral blood, at 30 and 60 dpi. Our data suggest that the persistence of parasite cysts induces sustained neuroinflammation, and BBB disruption, thus allowing leakage of cytokines of circulating plasma into the brain tissue. Therefore, all these factors may contribute to behavioral changes (anxiety, depressive-like behavior, and hyperactivity) in chronicT.gondiiinfection.