bluuebunny/crossref_metadata_2025 huggingface dataset:
M × N electrically controlled optofluidic matrix switch
Authors: Guo Mingrui , Wan Jing , Yuan Wenzhi , Zhu Xu , Chen Yijing , Wei Shuo
Published: October 2021

A completely non-blocking

M

×

N

electrically controlled optofluidic
matrix switch that uses a

1

×

3

optical switch with a V-shaped
microchannel as the switching unit is proposed. Its light paths and
output ports are selected by a micro-actuator matrix and a control
circuit. There are few reports of optofluidic matrix switches. Here
the given electrostatic micro-actuator and the basic switch structure
provide an effective feasible manner for the matrix switch due to the
simple and compact structure as well as the operation style. The
impacts of microchannels and intersecting waveguides on the switch
performance are discussed, and multiple optimization schemes are
proposed to reduce the insertion loss efficiently and significantly.
The research results indicate that the

M

×

N

matrix switch has the advantages of
good matrix controllability, simple structure, wide waveband
(400–1700 nm), negligible polarization-dependent loss, small insertion
loss, and low cross talk. For 1550 nm wavelength, the insertion loss
of a

2

×

6

matrix switch is about 0.17–0.55 dB,
and the maximum cross talk is less than

−

26.8

d
B

. In addition, the performance
parameters of a

4

×

8

matrix switch are given and compared
with other reported matrix switches. The proposed

M

×

N

matrix switch solves the problem of
large insertion loss of general optical matrix switches and can be
expanded to a large-scale matrix switch. Moreover, the design of
multiple output ports has more flexible applications in systems with
multiple branch optical paths and network nodes.
Photonic generation of a dual-chirp waveform with an optoelectronic oscillator based on stimulated Brillouin scattering
Authors: Zhou Weinan , Wang Di , Du Cong , Ding Yujiao , Dong Wei
Published: October 2021

A photonic method to generate a dual-chirp microwave waveform (DCMW) is proposed and demonstrated by utilizing a stimulated Brillouin scattering based optoelectronic oscillator and a frequency scanning laser source (FSLS). There are no radio frequency sources or Mach–Zehnder modulators in the proposed structure, which makes the system simple and stable. In the experiment, an alternative scheme is utilized to replace the FSLS, and the DCMW signal with a central frequency of 4.69 GHz is generated; the bandwidth of the generated DCMW signal is up to 7 GHz and the chirp rate up to

±

5.3

G
H
z

/

µ

s

. The autocorrelation and ambiguity function of the generated signal are also investigated and show good performance of pulse compression and reduction of range-Doppler coupling.
Lunar laser ranging based on a 100  Hz repetition frequency
Authors: Gao Tianquan , Zhou Lixiang , Zhang Caishi , Zhao Hongchao , Wu Xianlin , Li Ming
Published: October 2021

High-repetition-rate lunar laser ranging (LLR) has great prospects and significance. We
have successfully obtained the effective echo signals of all five
corner-cube reflectors (CCRs) on the lunar surface by using a 100 Hz
repetition rate. This method can effectively improve the detection
ability but has some defects: for example, the main wave and echo
signals overlap. In this paper, the frequency selection and signal
overlap are theoretically analyzed. The results show that the existing
target prediction accuracy can meet the requirement of a 100 Hz
repetition rate LLR. In the experiment, the use of a
high-repetition-rate pulse laser allowed us to obtain detailed CCR
information, such as the column number of CCRs, which will prove that
the effective echo signals of LLR are reflected by the CCRs. Finally,
we propose to use the resolved data to calculate the precision of
inner coincidence and believe the accuracy can be within a
millimeter.
Some displays of lens structural performance
Authors: Sasián José
Published: October 2021

Some useful displays that provide information about the performance of lens systems are presented and discussed in this paper. They are useful for comparing lenses, identifying problematic lens elements, and lens desensitizing and optimizing. An imaging simulation of a square wave is also presented to complement the modulation transfer function plots.
Efficient dynamic control method of light polarization using single phase-only liquid crystal on silicon spatial light modulators for optical data storage
Authors: Hong Jintao , Li Jin , Chu Daping
Published: October 2021

The technology of five-dimensional (5D) optical data storage in
transparent materials paves a promising way to unlimited lifetime data
storage for future cloud use. Phase-only liquid-crystal-on-silicon
spatial light modulators (LCOS SLMs) have already exhibited its
potential for this application in tailoring ultrafast laser writing
beams for 5D optical data storage. A phase-only LCOS SLM can generate
arbitrary data patterns by using diffractive holographic imaging for
data writing light beam generation. However, the polarization control
of the output holographic image is still achieved by using an external
polarization modulator, which leads to complications, bulkiness, and
large delays in current methods. In this paper, we presented an
efficient phase and polarization modulation method through a compact
system based on a single phase-only LCOS SLM to simultaneously control
both the holographic image and its polarization state. The proposed
method utilizes two-polarization-component coding in conjunction with
a polarization component rotation technique in a compact system. Using
this polarization rotation technique, two light components can be
independently coded by separately using two holograms on two halves of
the LCOS SLM. We experimentally construct a proof-of-concept prototype
of the compact system, and the effectiveness of the system has been
experimentally verified.
First demonstration of a C + L band CDC-ROADM with a simple node configuration using multiband switching devices
Authors: Yamamoto Shuto , Taniguchi Hiroki , Kisaka Yoshiaki , Camatel Stefano , Ma Yiran , Ogawa Daisuke , Hadama Koichi , Fukutoku Mitsunori , Goh Takashi , Suzuki Kenya
Published: October 2021

While ultrahigh-baud-rate optical signals are effective for extending the transmission distance of large capacity signals, they also reduce the number of wavelengths that can be arranged in a band because of their wider bandwidth. This reduces the flexibility of optical path configuration in reconfigurable optical add/drop multiplexing (ROADM) networks. Particularly in colorless, directionless and contentionless (CDC)-ROADM, the effect reduces the add/drop ratio at a node. Multiband ROADM systems are an effective countermeasure for overcoming this issue, but they make the node configuration more complicated and its operation more difficult. In this paper, we analyze the challenges of C + L band CDC-ROADM and show that optical switch devices that operate over multiple bands are effective in meeting them. For this purpose, we built a C + L band CDC-ROADM node based on C + L band wavelength-selective switches and multicast switches and confirmed its effectiveness experimentally. In particular, to simplify the node configuration, we propose a reduction in the number of optical amplifiers used for node loss compensation and experimentally verify its feasibility.
Shaping the topology of light with a moving Rabi-oscillating vortex
Authors: Dominici Lorenzo , Voronova Nina , Colas David , Gianfrate Antonio , Rahmani Amir , Ardizzone Vincenzo , Ballarini Dario , De Giorgi Milena , Gigli Giuseppe , Laussy Fabrice P. , Sanvitto Daniele
Published: October 2021

Quantum vortices are the analogue of classical vortices in optics, Bose-Einstein condensates, superfluids and superconductors, where they provide the elementary mode of rotation and orbital angular momentum. While they mediate important pair interactions and phase transitions in nonlinear fluids, their linear dynamics is useful for the shaping of complex light, as well as for topological entities in multi-component systems, such as full Bloch beams. Here, setting a quantum vortex into directional motion in an open-dissipative fluid of microcavity polaritons, we observe the self-splitting of the packet, leading to the trembling movement of its center of mass, whereas the vortex core undergoes ultrafast spiraling along diverging and converging circles, in a sub-picosecond precessing fashion. This singular dynamics is accompanied by vortex-antivortex pair creation and annihilation and a periodically changing topological charge. The spiraling and branching mechanics represent a direct manifestation of the underlying Bloch pseudospin space, whose mapping is shown to be rotating and splitting itself. Its reshaping is due to three simultaneous drives along the distinct directions of momentum and complex frequency, by means of the differential group velocities, Rabi frequency and dissipation rates, which are natural assets in coupled fields such as polaritons. This state, displaying linear momentum dressed with oscillating angular momentum, confirms the richness of multi-component and open quantum fluids and their innate potentiality to implement sophisticated and dynamical topological textures of light.
Accurate measurement of the photonic crystal slab period using diffraction in the Littrow configuration
Authors: Lawall John , Bao Yiliang , Gorman Jason J.
Published: October 2021

Photonic crystal slab devices with subwavelength periods can be tailored to provide remarkable functionality, such as ultrahigh reflectivity in a structure only 200 nm in thickness. Accurate measurement of the characteristics of these structures is essential to compare their performance to theoretical expectations and to better understand the origin of unexpected behavior. In this work, we present a simple non-invasive method employing diffraction of a visible wavelength reference in the Littrow configuration for measuring the period of a photonic crystal slab. We have measured periods of our devices with uncertainty below 0.5 nm and expect that the uncertainty could easily be improved by an order of magnitude. In addition to facilitating development, our approach can be used to explore possible variations in the period of the photonic crystal due to its operating environment and aging.
Azimuthal and radial modulation of double-four-wave mixing in a coherently driven graphene ensemble
Authors: Ding Chunling , Li Jiahua , Dai Xiao , Jin Rui-Bo , Hao Xiangying
Published: October 2021

We investigate in detail the azimuthal and radial modulation (i.e., the azimuthal order l
j
and radial order p
j
with j = 1, 2) of double-four-wave mixing (double-FWM) by use of two higher-order Laguerre-Gaussian (LG) beams in a Landau quantized graphene ensemble. A pair of weak probe pulses in the graphene ensemble interacts with two LG beams and thus two vortex FWM fields with the opposite vorticity are subsequently generated. In combination with numerical simulations, we reveal that (i) there appear l1 + l2 periods of phase jumps in the phase profiles under any conditions; (ii) p + 1 concentric rings emerge in the intensity profile and the strength is mainly concentrated on the inner ring when the two LG beams have the same radial orders (i.e., p1 = p2 = p); (iii) there are p raised narrow rings occurring in the phase profile in the case of p1 = p2 = p and l1 ≠ l2, and the raised narrow rings would disappear when p1 = p2 and l1 = l2; (iv) p
max
 + 1 concentric rings appear in the intensity profile, meanwhile, |p1 − p2| convex discs and p
min
raised narrow rings emerge in the phase diagram in the case of p1 ≠ p2, here p
max
 = max(p1, p2) and p
min
 = min(p1, p2). Moreover, the two generated FWM fields have the same results, and the difference is that the phase jumps are completely opposite. These findings may have potential application in graphene-based nonlinear optical device by using LG beams with adjustable mode orders.
Optical diffractive deep neural network-based orbital angular momentum mode add–drop multiplexer
Authors: Xiong Wenjie , Huang Zebin , Wang Peipei , Wang Xinrou , He Yanliang , Wang Chaofeng , Liu Junmin , Ye Huapeng , Fan Dianyuan , Chen Shuqing
Published: October 2021

Vortex beams have application potential in multiplexing communication because of their orthogonal orbital angular momentum (OAM) modes. OAM add–drop multiplexing remains a challenge owing to the lack of mode selective coupling and separation technologies. We proposed an OAM add–drop multiplexer (OADM) using an optical diffractive deep neural network (ODNN). By exploiting the effective data-fitting capability of deep neural networks and the complex light-field manipulation ability of multilayer diffraction screens, we constructed a five-layer ODNN to manipulate the spatial location of vortex beams, which can selectively couple and separate OAM modes. Both the diffraction efficiency and mode purity exceeded 95% in simulations and four OAM channels carrying 16-quadrature-amplitude-modulation signals were successfully downloaded and uploaded with optical signal-to-noise ratio penalties of ∼1 dB at a bit error rate of 3.8 × 10−3. This method can break through the constraints of conventional OADM, such as single function and poor flexibility, which may create new opportunities for OAM multiplexing and all-optical interconnection.
New strategy for high-dimensional single-pixel imaging
Authors: Li Xianye , Yin Yongkai , He Wenqi , Liu Xiaoli , Tang Qijian , Peng Xiang
Published: October 2021

Single-pixel imaging (SPI) technique has been studied intensively due to its minimum requirement for the detector resolution and the equipment costs. In this work, we proposed a new strategy of the SPI to explore its capability in high-dimensional imaging, which is the first comprehensive scheme as we know to achieve calibration, color texture and viewpoint expansion of single-pixel three-dimensional imaging. We realized a low-cost single-pixel three-dimensional imaging scheme which employ a raster scanner to provide the structured illumination and a grating to encode the height information. In order to reduce the blocking area, we introduce two single-pixel detectors (SPDs) to detect from two detection angles, a modified total variation based criterion is proposed to fuse the height information from two SPDs and reduce the error of shape fusion. To acquire the information of higher dimension, we introduce the third SPD aims to gain the color texture, three bandpass filter is placed in front of three SPDs, respectively, to collect different color information. Meanwhile a viewpoint switching method inspired by the shape from shading theory is presented to improve the color fidelity. Our study is expected to provide a demonstration for SPI in acquisition, reconstruction, and fusion of high-dimensional image data.
Diode-side-pumped watt-level high-energy Q-switched mid-IR Er:YLF laser
Authors: Pushkin A. V. , Slovinsky I. A. , Shakirov A. A. , Shavelev A. A. , Potemkin F. V.
Published: October 2021

We report on a powerful mid-IR diode-side-pumped tunable

E
r

:

L
i
Y
F

4

(Er:YLF) laser electro-optically

Q

-switched with the help of a

K
T
i
O
P
O

4

crystal. At a 20 Hz repetition rate, the laser pulses with output energy of 82 mJ and 13 ns duration at the wavelength of 2.67 µm are obtained. At higher repetition rates (up to 50 Hz), one can extract up to 20 mJ from the laser cavity. The developed mid-IR laser source demonstrates high peak (up to 6.3 MW) and average (up to 1.7 W) power. Realized wavelength tuning provides access for megawatt-peak power-level nanosecond laser pulses over the 2667–2851 nm wavelength region, which are highly demanded for mid-IR laser systems development and light–matter interaction study in the view of extreme-state creation in liquids and solids, paving the way to novel microprocessing techniques.
Broadband complementary vibrational spectroscopy with cascaded intra-pulse difference frequency generation
Authors: Hashimoto Kazuki , Ramaiah Badarla Venkata , Imamura Takayuki , Ideguchi Takuro
Published: October 2021

One of the essential goals of molecular spectroscopy is to measure all fundamental molecular vibrations simultaneously. To this end, one needs to measure broadband infrared (IR) absorption and Raman scattering spectra, which provide complementary vibrational information. A recently demonstrated technique called complementary vibrational spectroscopy (CVS) enables simultaneous measurements of IR and Raman spectra with a single device based on a single laser source. However, the spectral coverage was limited to

∼

1000

c

m

−
1

, which partially covers the spectral regions of the fundamental vibrations. In this work, we demonstrate a simple method to expand the spectral bandwidth of the CVS with a cascaded intra-pulse difference-frequency generation (IDFG). Using the system, we measure broadband CVS spectra of organic liquids spanning over

2000

c

m

−
1

, more than double the previous study.
Near-far IR photoconductivity damping in hyperdoped Si at low temperatures
Authors: Kudryashov Sergey , Boldyrev Kirill , Nastulyavichus Alena , Prikhod’ko Dmitry , Tarelkin Sergey , Kirilenko Demid , Brunkov Pavel , Shakhmin Alexander , Khamidullin Kamil , Krasin George , Kovalev Michael
Published: October 2021

Silicon p-n junction photoelement fabricated on a p-doped wafer by sulfur-based n-doping of its sub-micron thick surface layer, exhibits at liquid-helium temperatures impurity-based near-far IR (2–21

μ

m) photoconductivity spectra in the form of well-resolved separate bands of neutral and ionized atomic-like and cluster-like sulfur centers. Temperature variation in the range of 5–105 K demonstrates first at lower temperatures < 35 K strong damping of IR photoconductivity related to cluster-like sulfur centers with ultralow activation energy ≈ 4 meV, corresponding to excitation of the lowest energy of Raman-active phonon in orthorhombic crystalline sulfur lattice. Further increase in temperature results in the next damping step above 85 K for all spectral bands above 1800 cm-1 with higher activation energy ≈ 20 meV, representing the lowest energy of Raman-active vibration of octagon molecules in the crystalline sulfur. Broad near-far IR photosensitivity of the hyperdoped material, provided by the concentration-driven sulfur aggregation and quantum-level temperature control of its photoconductivity, paves the way for silicon photonics in far-IR and, possibly in the future, even THz spectral regions.
Wavelength-dependent multifunctional metalens devices via genetic optimization
Authors: Ren Jianzheng , Li Tianyue , Fu Boyan , Wang Shuming , Wang Zhenlin , Zhu Shining
Published: October 2021

Metalenses with non-trivial performance, abundant applications, and tremendous potential, have emerged as a flat optical element or configuration in recent years. The increasing concerns about how to integrate more functions into a single metalens have become a hot topic. Here, based on a genetic algorithm, we demonstrate several metalenses with more than two optical functions depending on the wavelength of light. We first design three arbitrary chromatic dispersive metalenses, whose focal planes can be determined at will at different wavelengths. Then, a metalens-based color router is presented, which is able to guide and focus the light with four wavelengths to different positions. Furthermore, we exhibit a tri-functional structured light generator to produce focused beam, focused orbital angular momentum beam, and the Bessel beam at three wavelengths, respectively. Our results may have potential applications in dispersion manipulation, optical micro-manipulation, and subwavelength resolution spectral imaging.
Thrombotic microangiopathy associated with arboviral infection: Report of 3 cases
Authors: Coelho Júnior José Luiz , Israel Karla Cristina Petruccelli , Machado Carlos Eduardo Everton , Muniz Monique Pereira Rêgo , Gatto Giuseppe Cesare , Barros Flávio Henrique Soares , Cunha Kaile de Araújo , de Lacerda Marcus Vinícius Guimarães , Neves Precil Diego Miranda de Menezes , Silva Gyl Eanes Barros
Published: October 2021

Dengue fever and chikungunya are viral diseases that have spread rapidly throughout the world in recent decades. The occurrence of complications is well known, including prerenal acute kidney injury (AKI), which is usually thought to be caused by dehydration and fluid loss. Thrombotic microangiopathy (TMA) is an uncommon aggravation of dengue fever and chikungunya, with only a few cases described in the medical literature. The aim of this study is to present 3 cases of TMA associated with arboviral infection. Three patients with clinical history, laboratory test, and kidney biopsy results compatible with TMA were selected for the study, 2 of whom had a serological diagnosis of dengue fever and 1 of chikungunya. The 3 patients were followed up at the Federal University of Maranhão Hospital’s Nephrology Service in 2018. A targeted gene panel sequencing (TGPS) plus multiple to atypical hemolytic uremic syndrome (aHUS) multiplex ligation–dependent probe amplification (MLPA) was performed in 2 of the patients and revealed in the patient 1 a heterozygous pathogenic variant in the geneTHBD, as well as heterozygous deletions inCFH,CFHR1, andCFHR3. In the patient 2, there were heterozygous pathogenic variant in the genesCFIandCFB, in addition to heterozygous deletions in the genesCFHR1andCFHR3. Both received treatment with eculizumab and undergone recovery of renal function. The third patient had TMA not classified as either aHUS or thrombotic thrombocytopenic purpura (TTP); he abandoned the treatment and returned to the service after 2 years for a dialysis emergency. Patients with arboviral infectious disease and changes that suggest TMA should have appropriate support to establish early diagnosis and useful treatment.
Intracluster correlation coefficients in a large cluster randomized vaccine trial in schools: Transmission and impact of shared characteristics
Authors: Whelan Jane , Marshall Helen , Sullivan Thomas R.
Published: October 2021

Cluster randomized trials (cRCT) to assess vaccine effectiveness incorporate indirect effects of vaccination, helping to inform vaccination policy. To calculate the sample size for a cRCT, an estimate of the intracluster correlation coefficient (ICC) is required. For infectious diseases, shared characteristics and social mixing behaviours may increase susceptibility and exposure, promote transmission and be a source of clustering. We present ICCs from a school-based cRCT assessing the effectiveness of a meningococcal B vaccine (Bexsero, GlaxoSmithKline) on reducing oropharyngeal carriage of Neisseria meningitidis (Nm) in 34,489 adolescents from 237 schools in South Australia in 2017/2018. We also explore the contribution of shared behaviours and characteristics to these ICCs. The ICC for carriage of disease-causing Nm genogroups (primary outcome) pre-vaccination was 0.004 (95% CI: 0.002, 0.007) and for all Nm was 0.007 (95%CI: 0.004, 0.011). Adjustment for social behaviours and personal characteristics reduced the ICC for carriage of disease-causing and all Nm genogroups by 25% (to 0.003) and 43% (to 0.004), respectively. ICCs are also reported for risk factors here, which may be outcomes in future research. Higher ICCs were observed for susceptibility and/or exposure variables related to Nm carriage (having a cold, spending ≥1 night out socializing or kissing ≥1 person in the previous week). In metropolitan areas, nights out socializing was a highly correlated behaviour. By contrast, smoking was a highly correlated behaviour in rural areas. A practical example to inform future cRCT sample size estimates is provided.
Stakeholder theory and management: Understanding longitudinal collaboration networks
Authors: Fares Julian , Chung Kon Shing Kenneth , Abbasi Alireza
Published: October 2021

This paper explores the evolution of research collaboration networks in the ‘stakeholder theory and management’ (STM) discipline and identifies the longitudinal effect of co-authorship networks on research performance, i.e., research productivity and citation counts. Research articles totaling 6,127 records from 1989 to 2020 were harvested from the Web of Science Database and transformed into bibliometric data using Bibexcel, followed by applying social network analysis to compare and analyze scientific collaboration networks at the author, institution and country levels. This work maps the structure of these networks across three consecutive sub-periods (t1: 1989–1999;t2: 2000–2010;t3: 2011–2020) and explores the association between authors’ social network properties and their research performance. The results show that authors collaboration network was fragmented all through the periods, however, with an increase in the number and size of cliques. Similar results were observed in the institutional collaboration network but with less fragmentation between institutions reflected by the increase in network density as time passed. The international collaboration had evolved from an uncondensed, fragmented and highly centralized network, to a highly dense and less fragmented network int3. Moreover, a positive association was reported between authors’ research performance and centrality and structural hole measures int3as opposed to ego-density, constraint and tie strength int1. The findings can be used by policy makers to improve collaboration and develop research programs that can enhance several scientific fields. Central authors identified in the networks are better positioned to receive government funding, maximize research outputs and improve research community reputation. Viewed from a network’s perspective, scientists can understand how collaborative relationships influence research performance and consider where to invest their decision and choices.
The impact of the COVID-19 response on the provision of other public health services in the U.S.: A cross sectional study
Authors: Kintziger Kristina W. , Stone Kahler W. , Jagger Meredith A. , Horney Jennifer A.
Published: October 2021

Introduction

Funding and staff formerly dedicated to routine public health tasks (e.g., responding to communicable and non-communicable diseases, investigating foodborne outbreaks, conducting routine surveillance) and services (e.g., environmental health, substance abuse, maternal-child health) may no longer be available in many public health departments due to the COVID-19 response. The objective of this study was to assess the extent to which staffing for essential public health services has been redirected to the COVID-19 response.

Materials and methods

This is a cross-sectional study using a survey distributed through the Qualtrics platform. Individuals (N = 298) working in public health across governmental and academic public health departments in the U.S. during the ongoing COVID-19 pandemic response were surveyed. Survey items measured multiple domains including professional experience (i.e., training, years of experience, content expertise, job functions, hours worked), mental and physical health status (i.e., generalized anxiety, depression, burnout), and career plans (i.e., pre-pandemic vs. current career plans).

Results

The total number of content expertise areas and programmatic functions covered by individual public health workers increased between January and September of 2020, with 26% (73 of 282) of respondents reporting an increase in both. The total number of respondents working in infectious disease and preparedness remained constant, while declines were reported in program evaluation (-36%) and health education (-27%) and increases were reported in disease investigation (+35%).

Conclusions

The provision of many essential public health functions and tasks have been limited or eliminated while the U.S. public health workforce responds to the COVID-19 pandemic. These findings highlight opportunities for funding and professional development of public health systems, both during and after the COVID-19 response, to help ensure the continuity of essential public health services, staffing sustainability, and preparedness for future public health emergencies in the U.S.
Knowledge and practice of cattle handlers on antibiotic residues in meat and milk in Kwara State, Northcentral Nigeria
Authors: Olasoju Mary Idowu , Olasoju Taiwo Israel , Adebowale Oluwawemimo Oluseun , Adetunji Victoria Olusola
Published: October 2021

Objectives

Antibiotics are important for improving animal health and production. However, the deposition of its residues in food of animal origin intended for human consumption at non-permissible levels has generated global health concern and the need to tackle this using the “One Health Approach”. This study assessed the knowledge and practice of 286 cattle handlers in Kwara State, Nigeria.

Methods

A web-based cross sectional online survey using a semi-structured questionnaire was conducted from November to December, 2019. Univariate, bivariate and multivariate analyses were performed at 95% confidence interval to determine predictors of good knowledge and practices towards Antibiotic Residues in Meat and Milk among cattle handlers.

Results

This study revealed that majority (52.7% n = 165/286) of the cattle handlers were not aware of antibiotic residues. Knowledge and practices regarding antibiotic residues were generally poor among the study population; 36.7% and 35.5% had satisfactory knowledge and practice respectively. The age (p = 0.026), gender (p = 0.006) and business duration (p = 0.001) of participants were significantly associated with their knowledge of antimicrobial residues. The effect of education on knowledge was modified by age. The odds of having poor knowledge on antibiotic residues increased 4 times among participants who were ≤40 years old than those above 40 years (Stratum Specific OR = 3.65; CI = 1.2, 11.1; p = 0.026). Knowledge levels of participants were statistically associated with their practice levels p<0.05 (OR = 2.43; CI = 1.45. 4.06; p = 0.0006).

Conclusion

This implies that poor knowledge is a risk factor to having poor practice among cattle handlers. Deliberate efforts towards educating cattle farmers on best farm practices in antibiotic use would prevent antibiotic residues in meat and milk. Also, an effective surveillance system for monitoring the use of veterinary drugs in Kwara State, Nigeria is crucial.
The effect of COVID-19 pandemic on final year dental students’ self-confidence level in performing clinical procedures
Authors: Ilić Jugoslav , Radović Katarina , Savić-Stanković Tatjana , Popovac Aleksandra , Miletić Vesna , Milić Lemić Aleksandra
Published: October 2021

Background

The outbreak of COVID-19 pandemic in 2020 has dramatically changed teaching approach in dental schools due to the switch to distance learning and the lack of practice training in direct contact with patients with possible impact on clinical skills of students. The aim of the study was to assess the level of the 2020 final year dental students’ self-confidence in performing different dental procedures through specially designed questionnaire and compare it to self-confidence of the 2019 final year students.

Materials and methods

An anonymous questionnaire consisting of 40 questions regarding self-confidence level in performing 40 different dental procedures and based on five points Likert-like scale was distributed during November 2020 to final year dental students whose studies were disrupted by the COVID-19 pandemic lockdown in one semester. The study group comprised their answers. The comparison was done with the control group that consisted of students’ answers on the same questionnaire from previous 2019 year conducted as a part of regular internal educational evaluation.

Results

Response rate was 74.2% in study group and 89.3% in control group. Mean level of self-confidence reported by 115 students in study group was significantly lower than that reported by 100 students in control group (3.28±1.08 vs. 3.58±0.88, respectively) and the distribution of self-confidence scores were different in observed groups. Graduates from study group felt less confident than those from control in 8 clinical skills.

Conclusion

Abrupt changes in teaching modalities caused by COVID-19 pandemic had significant impact on final year dental students’ self-confidence indicating additional educational needs in postgraduate period.
Regional diversification of the use of agricultural production potential in the EU candidate and the Eastern partnership countries
Authors: Jankowska Anna
Published: October 2021

Diversification of the agricultural production potential often implies the differentiation of the achieved farming productivity due to its effect on the agricultural resources and structural processes. The article aims to examine the diversity of the production potential in the agricultural sectors of the EU candidate countries (CC) and the Eastern Partnership countries (EPC) and its impact on the variety of the achieved productivity, as well as to present changes in the analyzed indicators in the years 2006–2017. A synthetic measure of agricultural development and a linear regression analysis were applied in the article. The research revealed that Belarus may be distinguished with regard to its production potential, as well as the achieved productivity. In most countries (with the exception of Montenegro and Macedonia), an increase in the value of the synthetic measure of the possessed potential has been recorded in the studied period. However, the synthetic measure of the agricultural productivity level displayed an insignificant raise only in half of the countries surveyed.
Health system responsiveness in maternity care at Hadiya zone public hospitals in Southern Ethiopia: Users’ perspectives
Authors: Abdo Ritbano Ahmed , Halil Hassen Mosa , Kebede Biruk Assefa , Anshebo Abebe Alemu , Ayalew Minychil Demelash , Nedamo Selamu Abose , Helill Shamill Eanga
Published: October 2021

Background

Health system responsiveness refers to non-financial, non-clinical qualities of care that reflect respect for human dignity and interpersonal aspects of the care process. The non-clinical aspects of the health system are therefore essential to the provision of services to patients. Therefore, the main purpose of this study was to assess the responsiveness in maternity care, domain performance and factors associated with responsiveness in maternity care in the Hadiya Zone public Hospitals in Southern Ethiopia.

Methods

A hospital-based cross-sectional study was employed on 413 participants using a systematic sampling technique from 1 July to 1 August 2020. An exit interviewer–administered questionnaire was used to collect data. EpiData (version 3.1) and SPSS (version 24) software were used for data entry and analysis, respectively. Bivariate and multivariable logistic regression were computed to identify the associated factors of health system responsiveness in maternity care at 95% CI.

Results

The findings indicated that 53.0% of users gave high ratings for responsiveness in delivery care. In the multivariable logistic regression analysis, mothers aged ≥ 35 (AOR = 0.4; 95% CI = 0.1–0.9), urban resident (AOR = 2.5; 95% CI = 1.5–4.8), obstetrics complications during the current pregnancy (AOR = 2.1; 95% CI = 1.1–3.0), and caesarean delivery (AOR = 0.4; 95% CI = 0.2–0.7) were factors associated with poor ratings for responsiveness in maternity care.

Conclusion

In the hospitals under investigation, responsiveness in maternity care was found to be good. The findings of this study suggest that the ministry of health and regional health bureau needs to pay attention to health system responsiveness as an indicator of the quality of maternity care.
An ethnobotanical study of wetland flora of Head Maralla Punjab Pakistan
Authors: Iqbal Muhammad Sajjad , Ahmad Khawaja Shafique , Ali Muhammad Azhar , Akbar Muhammad , Mehmood Ansar , Nawaz Fahim , Hussain Syed Atiq , Arshad Noshia , Munir Saba , Arshad Hamna , Shahbaz Khizra , Bussmann Rainer W.
Published: October 2021

Background

Wetlands are biologically diverse and highly productive ecosystems that support one-third of all threatened and endangered plants of the world. Wetland plants have been studied ethnobotanically much less than terrestrial plants, including in Pakistan, thus information about the uses of local wetland plants in traditional healthcare system is scare. Head Maralla is a non-recognized wetland with diversified flora that has been focused of the current study.

Methods

The ethnobotanical data were collected from four sites viz., River Tavi, Upstream Chenab, River Manawarwala Tavi, and Bhalolpur through questionnaire and interviews during field trips. Quantitative indices including informant consensus factor (ICF), cultural significant indext (CSI), relative frequency of citation (RFC), and use value (UV) were used to analyze the data.

Results

On the whole, 119 plant species were identified belonging to 54 families, of which 87 species were dicot, 12 monocots, 11 aquatic, 5 ferns, and 4 species were bryophytes. Of these, 50% of the plant species were utilized for therapeutic purposes, followed by leaves which had more than 20% usage of total consumption. Herbs were the primary source of medicine (73 spp) followed by trees (22 spp), weeds (11 spp), shrubs (9 spp), foliose (2 spp) and thaloids (2 spp) in the area. Ficranged from 0.66 to 0.93 for constipation and respiratory disorders with an average Ficof 0.87 reflecting a high consensus among the informants about the use of plants to treat particular ailment. Major ailments viz., urination (14%), cough (8.40%), cold (6.70%), stomach (5.90%), asthma (5.90%), skin infection (5%), constipation (5%), and diarrhea (4%) etc., were treated with local plant recipes. The highest CSI value was found forA.vesica(7.55) widely used in respiratory disorders and in digestive problems. RFC ranged from 0.92 to 0.15 with the maximum value obtained forR.communis(0.95). The use values ranged from 0.03 to 0.90 with the maximum use value forR.communis(0.90). A positive correlation was found between CSI and RFC (r = 0.29), and CSI and UV (r = 0.29). The JI values ranged from 7.14 to 0.14 indicating strong affinity with Samahani valley, Azad Kashmir, Pakistan. Unique speciesOsmunda regaliswas first time reported from Pakistan with novel uses for renal and blood purifier. Fifteen percent (15%) plants contribute as fodder species consumed by local community for livestock while almost 6.7% species were utilized for timber and fuel purposes.

Conclusion

The ecosystem of Head Maralla provide a complex habitat for aqauatic, terrestrial, and agriculture wetland vegetation. It is suggested that conservation efforts should be made to conserve the ethnoecological knowledge of these areas and pharmacological studies should be conducted for noval drug synthesis in future.
Meta-Analysis illustrates possible role of lipopolysaccharide (LPS)-induced tissue injury in nasopharyngeal carcinoma (NPC) pathogenesis
Authors: Allen David Z. , Aljabban Jihad , Silverman Dustin , McDermott Sean , Wanner Ross A. , Rohr Michael , Hadley Dexter , Panahiazar Maryam
Published: October 2021

Background

Nasopharyngeal carcinoma (NPC) is a cancer of epithelial origin with a high incidence in certain populations. While NPC has a high remission rate with concomitant chemoradiation, recurrences are frequent, and the downstream morbidity of treatment is significant. Thus, it is imperative to find alternative therapies.

Methods

We employed a Search Tag Analyze Resource (STARGEO) platform to conduct a meta-analysis using the National Center for Biotechnology’s (NCBI) Gene Expression Omnibus (GEO) to define NPC pathogenesis. We identified 111 tumor samples and 43 healthy nasopharyngeal epithelium samples from NPC public patient data. We analyzed associated signatures in Ingenuity Pathway Analysis (IPA), restricting genes that showed statistical significance (p<0.05) and an absolute experimental log ratio greater than 0.15 between disease and control samples.

Results

Our meta-analysis identified activation of lipopolysaccharide (LPS)-induced tissue injury in NPC tissue. Additionally, interleukin-1 (IL-1) and SB203580 were the top upstream regulators. Tumorigenesis-related genes such as homeobox A10 (HOXA10) and prostaglandin-endoperoxide synthase 2 (PTGS2 or COX-2) as well as those associated with extracellular matrix degradation, such as matrix metalloproteinases 1 and 3 (MMP-1, MMP-3) were also upregulated. Decreased expression of genes that encode proteins associated with maintaining healthy nasal respiratory epithelium structural integrity, including sentan-cilia apical structure protein (SNTN) and lactotransferrin (LTF) was documented. Importantly, we found that etanercept inhibits targets upregulated in NPC and LPS induction, such as MMP-1, PTGS2, and possibly MMP-3.

Conclusions

Our analysis illustrates that nasal epithelial barrier dysregulation and maladaptive immune responses are key components of NPC pathogenesis along with LPS-induced tissue damage.
Early bilingual immersion school program and cognitive development in French-speaking children: Effect of the second language learned (English vs. Dutch) and exposition duration (2 vs. 5 years)
Authors: Gillet Sophie , Barbu Cristina , Poncelet Martine
Published: October 2021

The results of studies targeting cognitive and academic advantages in children frequenting early bilingual immersion school programs (CLIL) have been contradictory. While the impact of the amount of CLIL experience has already been studied, the role of the second language learned has been little studied to account for differences among study findings. The link between executive skills (EF) and scholar abilities (e.g., mathematics) in the CLIL context has also been little investigated. The purpose of the present study was to determine if the impact of CLIL on EF and academic performances varies depending on the immersion language and the duration of CLIL experience. The sample included a total of 230 French-speaking children attending second (141) and fifth (89) grade classes. Within each grade, there were three matched language groups composed of children respectively immersed in English, immersed in Dutch, and non-immersed controls. The children were administered tasks assessing executive functions [alerting, cognitive flexibility, and working memory], as well as arithmetic abilities. In second grade, we detected no difference in EF between the language groups. On the other hand, in fifth grade, the two immersed groups outperformed the non-immersed group on the cognitive flexibility task but did not differ between them. Moreover, only the Dutch immersed group outperformed the control group on the working memory task. Arithmetic performances also differed depending on the language learned; in second grade, Dutch learners performed better than the monolingual group. In fifth grade, Dutch learners outperformed the two other groups. These results suggest that the impact of CLIL on executive skills and arithmetic performances might be modulated by the amount of CLIL experience and the second language learned in immersion.
Ultrastructural changes in methicillin-resistant Staphylococcus aureus (MRSA) induced by metabolites of thermophilous fungi Acrophialophora levis
Authors: Agrawal Shivankar , Nandeibam Jusna , Sarangthem Indira
Published: October 2021

Staphylococcus aureus and Methicillin-resistant S. aureus (MRSA) remains one of the major concerns of healthcare associated and community-onset infections worldwide. The number of cases of treatment failure for infections associated with resistant bacteria is on the rise, due to the decreasing efficacy of current antibiotics. Notably, Acrophialophora levis, a thermophilous fungus species, showed antibacterial activity, namely against S. aureus and clinical MRSA strains. The ethyl acetate extract of culture filtrate was found to display significant activity against S. aureus and MRSA with a minimum inhibitory concentration (MIC) of 1 μg/mL and 4 μg/mL, respectively. Scanning electron micrographs demonstrated drastic changes in the cellular architecture of metabolite treated cells of S. aureus and an MRSA clinical isolate. Cell wall disruption, membrane lysis and probable leakage of cytoplasmic are hallmarks of the antibacterial effect of fungal metabolites against MRSA. The ethyl acetate extract also showed strong antioxidant activity using two different complementary free radicals scavenging methods, DPPH and ABTS with efficiency of 55% and 47% at 1 mg/mL, respectively. The total phenolic and flavonoid content was found to be 50 mg/GAE and 20 mg/CAE, respectively. More than ten metabolites from different classes were identified: phenolic acids, phenylpropanoids, sesquiterpenes, tannins, lignans and flavonoids. In conclusion, the significant antibacterial activity renders this fungal strain as a bioresource for natural compounds an interesting alternative against resistant bacteria.
Clinical and epidemiological characteristics of patients seeking COVID-19 testing in a private centre in Malaysia: Is there a role for private healthcare in battling the outbreak?
Authors: Chow Yock Ping , Chin Brenda Huey Zien , Loo Jin Ming , Moorthy Loshini R. , Jairaman Jamuna , Tan Lian Huat , Tay Wendy Wan Ying
Published: October 2021

Objective

This cross-sectional observational study summarized the baseline characteristics of subjects who underwent COVID-19 molecular testing in a private medical centre located in the state of Selangor in Malaysia between 1 Oct 2020 and 31 Jan 2021. We compared the baseline characteristics between subjects who were tested positive and negative of SARS-CoV-2 infection, and identified risk factors which may be predictive of SARS-CoV-2 positivity.

Methods and findings

A total of 36603 subjects who were tested for COVID-19 infection via molecular assays at Sunway Medical Centre between Oct 1, 2020 and Jan 31, 2021, and consented to participate in this observation study were included for analysis. Descriptive statistics was used to summarize the study cohort, whereas logistic regression analysis was used to identify risk factors associated with SARS-CoV-2 positivity. Among the reasons listed for COVID-19 screening were those who needed clearance for travelling, clearance to return to work, or clearance prior to hospital admission. They accounted for 67.7% of tested subjects, followed by the self-referred group (27.3%). Most of the confirmed cases were asymptomatic (62.6%), had no travel history (99.6%), and had neither exposure to SARS-CoV-2 confirmed cases (61.9%) nor exposure to patients under investigation (82.7%) and disease clusters (89.2%). Those who presented with loss of smell or taste (OR: 26.91; 95% CI: 14.81–48.92, p<0.001), fever (OR:3.97; 95% CI: 2.54–6.20, p<0.001), running nose (OR: 1.75; 95% CI:1.10–2.79, p = 0.019) or other symptoms (OR: 5.63; 95% CI:1.68–18.91, p = 0.005) were significantly associated with SARS-CoV-2 positivity in the multivariate logistic regression analysis.

Conclusion

Our study showed that majority of patients seeking COVID-19 testing in a private healthcare setting were mainly asymptomatic with low epidemiological risk. Consequently, the average positivity rate was 1.2% compared to the national cumulative positivity rate of 4.65%. Consistent with other studies, we found that loss of smell or taste, fever and running nose were associated with SARS-CoV-2 positivity. We believe that strengthening the capacity of private health institutions is important in the national battle against the COVID-19 pandemic, emphasizing the importance of public-private partnership to improve the quality of clinical care.