bluuebunny/crossref_metadata_2025 huggingface dataset:
Hybrid IPSO-IAGA-BPNN algorithm-based rapid multi-objective optimization of a fully parameterized spaceborne primary mirror
Authors: Qin Tao , Guo JunLi , Jing ZiJian , Han PeiXian , Qi Bo
Published: March 2021

The surface figure precision, weight, and dynamic performance of spaceborne primary mirrors depend on mirror structure parameters, which are usually optimized to improve the overall performance. To realize rapid multi-objective design optimization of a primary mirror with multiple apertures, a fully parameterized primary mirror structure is established. A surrogate model based on a hybrid of improved particle swarm optimization (IPSO), adaptive genetic algorithm (IAGA), and optimized back propagation neural network (IPSO-IAGA-BPNN) is developed to replace optomechanical simulation with its high computational cost. In this model, a self-adaptive inertia weight and a modified genetic operator are introduced into the particle swarm optimization (PSO) and adaptive genetic algorithm (AGA), respectively. The connection parameters of BPNN are optimized by the IPSO-IAGA algorithm for global searching capability. Further, the proposed IPSO-IAGA-BPNN, based on a rapid multi-objective optimization framework for a fully parameterized primary mirror structure, is established. Moreover, in addition to the proposed IPSO-IAGA-BPNN model, the Kriging, RSM, BPNN, GA-BPNN, PSO-BPNN, and PSO-GA-BPNN models are also analyzed as contrast models. The comparison results indicate that the predicted value obtained by IPSO-IAGA-BPNN is superior to the six other surrogate models since its mean absolute percentage error is less than 3% and its

R
2

is more than 0.99. Finally, we present a Pareto-optimal primary mirror design and implement it through three optimization methods. The verification results show that the proposed method predicts mirror structural performance more accurately than existing surrogate-based methods, and promotes significantly superior computational efficiency compared to the conventional integration-based method.
Characterization of YAG:Ce phosphor dosimeter by the co-precipitation method for radiotherapy
Authors: Guo Qiang , Li Mao , Yue Kun , Yan Yuheng , Xie Feiyang , Zhang Changfeng , Mou Chengbo , Peng Gang-Ding
Published: March 2021

Yttrium aluminum garnet (YAG) doped with Ce was synthesized via the co-precipitation method with

N
H

4

H
C
O

3

as the precipitant. The spectroscopic properties and the effects of the Ce doping concentration and sintering atmosphere on the crystal phase were investigated. The dosimeter of YAG:Ce phosphor material was prepared to study the radioluminescence (RL) characteristics of a clinical linear accelerator. A satisfying linear relationship between the radiation dose and RL signal was obtained, which provided a reference for the YAG:Ce phosphor material used in radiotherapy and real-time remote radiation detection.
Physics-guided neural network for predicting chemical signatures
Authors: Murphy Cara P. , Kerekes John P.
Published: March 2021

Achieving high classification accuracy on trace chemical residues in active spectroscopic sensing is challenging due to the limited amount of training data available to the classifier. Such classifiers often rely on physics-based models for generating training data though these models are not always accurate when compared to measured data. To overcome this challenge, we developed a physics-guided neural network (PGNN) for predicting chemical reflectance for a set of parameterized inputs that is more accurate than the state-of-the-art physics-based signature model for chemical residues. After training the PGNN, we use it to generate a library of predicted spectra for training a classifier. We compare the classification accuracy when using this PGNN library versus a library generated by the physics-based model. Using the PGNN, the average classification accuracy increases from 0.623 to 0.813 on real chemical reflectance data, including data from chemicals not included in the PGNN training set.
Using an artificial neural network to predict the residual stress induced by laser shock processing
Authors: Wu Jiajun , Liu Xuejun , Qiao Hongchao , Zhao Yongjie , Hu Xianliang , Yang Yuqi , Zhao Jibin
Published: March 2021

With the purpose of using the artificial neural network (ANN) method to predict the residual stresses induced by laser shock processing (LSP), the Ni-Cr-Fe-based precipitation-hardening superalloy GH4169 was selected as the experimental material in this work, and the experimental samples were treated by LSP with laser power densities of

4.24

G
W

/

c
m

2

,

7.07

G
W

/

c
m

2

, and

9.90

G
W

/

c
m

2

and overlap rates of 10%, 30%, and 50%. The depth-wise residual stresses of experimental samples prior to and after LSP were taken according to the x-ray diffraction

sin

2

ψ

method and electrolytic-polished layer by layer. The ANN model for residual stress prediction was established, and the laser power density, overlap rate, and depth were set as input parameters, while residual stress was set as the output parameter. The residual stresses of untreated samples and those treated with laser power densities of

4.24

G
W

/

c
m

2

and

9.90

G
W

/

c
m

2

were selected as the training sets, and the data of experimental samples treated with a laser power density of

7.07

G
W

/

c
m

2

were reserved as testing sets for validating the trained network. After LSP, beneficial stable compressive residual stresses were introduced in the material’s near surface, and the overall maximum compressive residual stresses were formed on the top surface (surface residual stress). Depending on the LSP process parameters, the surface residual stresses ranged from

−

236

M
P
a

to

−

799

M
P
a

, and the compressive residual stress depths of all treated samples were over 0.50 mm. According to the results obtained by ANN, the coefficient of determination

R
2

of the training sets is 0.9948, which shows a good fitness for the training network. The

R
2

of the testing sets is 0.9931, which is less than that of the training sets but still shows high accuracy. This work proves that the ANN method can be applied to predict the residual stress of metallic materials by LSP treatment with high accuracy and provides a guiding value for the optimization of the LSP process.
Cholesteric liquid crystal mirror-based imaging Stokes polarimeter
Authors: Petriashvili Gia , Chanishvili Andro , Wardosanidze Zurab
Published: March 2021

We have developed a cholesteric liquid crystal (CLC) mirror-based innovative model for detection and visualization of images in turbid media. Due to its unique optical-polarization properties, the CLC mirror is suggested as the basic element of the imaging Stokes polarimeter. The particular design of the proposed polarimeter, coupled with its distinguished operational simplicity, reliability, and real-time operational facilities, promises to fabricate a new generation of the imaging Stokes polarimeter, which can find applications in areas such as diagnostics, biology, astronomy, and remote sensing.
Iterative reconstruction algorithm based on discriminant adaptive-weighted TV regularization for fibrous biological tissues using in-line X-ray phase-contrast imaging
Authors: Zheng Mengting , Zhao Yuqing , Han Shuo , Ji Dongjiang , Li Yimin , Lv Wenjuan , Xin Xiaohong , Zhao Xinyan , Hu Chunhong
Published: March 2021

In-line X-ray phase-contrast computed tomography (IL-PCCT) can produce high-contrast and high-resolution images of biological samples, and it has a great advantage with regard to imaging the microstructures and morphologies of fibrous biological tissues (FBTs). Filtered back projection (FBP) is widely used in ILPCCT. However, it requires long scanning times and high radiation doses to produce high-quality CT images, and this restricts its applicability in biomedical and preclinical studies on FBTs. To solve this problem, a novel IL-PCCT reconstruction algorithm is proposed to decrease the radiation dose by reducing the number of projections and reconstruct high-quality CT images of FBTs. The proposed algorithm incorporates the FBP method into the iterative reconstruction framework. Considering the area types and anisotropic edge properties of FBTs, a discriminant adaptive-weighted total variation model is introduced to optimize the intermediate reconstructed images. A fibrous phantom simulation and real experiment were performed to assess the performance of the proposed algorithm. Simulation and experimental results demonstrated that the proposed algorithm is an effective IL-PCCT reconstruction method for FBTs with incomplete projection data, and it has a great ability to suppress artifacts and preserve the edges of fibrous structures.
Goos–Hänchen shift enhancement based on an improved differential evolution algorithm
Authors: Han Lei , Xu Chaoyu , Huang Tianye , Dang Xueyan , Li Chengying
Published: March 2021

The Goos–Hänchen (GH) shift is one of the important aspects to evaluate the performance of multilayer surface plasmon resonance (SPR) sensors. However, the conventional SPR sensor design procedure based on the fixed parameter scanning (FPS) method is complex and time-consuming, and makes it difficult to gain the optimized design. In this paper, in order to design the optimal GH-shift-based SPR sensor, an improved differential evolution (IDE) algorithm based on chaos mapping, fitness elimination mechanism, nonlinear scale factor, and cross probability control strategy is proposed. By using such an IDE algorithm, the Ag‐ITO‐TMDCs‐graphene structure can be optimized. By the IDE algorithm, after 9 iterations, the maximum fitness value is obtained in the Ag‐ITO‐

M
o
S

2

-graphene structure, the maximum GH shift is

16591

λ

, and the sensitivity is

3.3

×

10

8

λ

/

R
I
U

. Compared with the FPS method, the GH shift is increased 192 times, and the sensitivity is increased 25,707.6 times. Compared with the DE algorithm, the number of iterations and the efficiency of the IDE algorithm are enormously improved as well. Such an algorithm provides a new, to the best of our knowledge, approach for designing a multilayer SPR sensor.
Can orthogonalization enhance the EPR correlation and the teleportation fidelity of a two-mode squeezed vacuum?
Authors: Liu Cun-Jin , Li Min-Xiang , Yuan Hong-Chun , Xu Xue-Xiang
Published: March 2021

For the first time, to the best of our knowledge, based on a two-mode squeezed vacuum (TMSV), we introduce photon-added orthogonal TMSVs and photon-subtracted orthogonal TMSVs via multiphoton addition

a

†
k

b

†
l

and multiphoton subtraction

a
k

b
l

(

k

,

l

are arbitrary integers). As a comparison, we also consider photon-added TMSVs and photon-subtracted TMSVs. We theoretically analyze Einstein–Podolsky–Rosen (EPR) correlation and teleportation fidelity for all these two-mode states. Our results indicate that orthogonalization cannot enhance EPR correlation and teleportation fidelity, at least so far.
Measurement-feedback control of the chiral photon emission from an atom chain into a nanofiber
Authors: Buonaiuto G. , Lesanovsky I. , Olmos B.
Published: March 2021

We theoretically investigate measurement-based feedback control of a laser-driven one-dimensional atomic chain interfaced with a nanofiber. The interfacing leads to all-to-all interactions among the atomic emitters and induces chirality (i.e., the directional emission of photons into a preferred guided mode of the nanofiber). In the setting we consider, the measurement of guided light—conducted either by photon counting or through homodyne detection of the photocurrent quadratures—is fed back into the system through modulation of the driving laser field. We investigate how this feedback scheme allows control of the statistics of the photon counting and the quadratures of the light, as well as the many-body state of the atom chain. In particular, we identify regimes where both the photon counting rate and its fluctuations are dramatically enhanced. Moreover, we find that the action of homodyne detection feedback allows the alteration of the stationary state of the chain from a pure, dimer state, to a fully mixed one. Our results provide insights on how to control and engineer dynamics in light–matter networks realizable with state-of-the-art experimental setups.
Chip-level Ce:GdYAG ceramic phosphors with excellent chromaticity parameters for high-brightness white LED device
Authors: Xi Xiaoqian , Zhang Le , Kang Jian , Li Yanbin , Wang Zhongying , Fei Bin , Cheng Xin , Huang Guocan , Li Ming , Chen Hao
Published: March 2021

Development of ceramic phosphors (CPs) featuring small volume and high efficacy is crucial for miniaturization of white LEDs and their integration in solid state lighting. In this study, the chip-level 2.5×2.5 mm Ce:GdYAG CPs with different thicknesses were packaged to the blue chips, and their luminous characteristics were analyzed under the different radiant flux. Notably, when thickness of the CPs was 1.4 mm, a luminous flux of 2000 lm, a correlated color temperature (CCT) of 6266 K and a color rendering index (CRI) of 70 were obtained under 11.0 W blue power (1.76 W/mm2) excitation. Phenomenon of colorimetric drift was explained simultaneously. These results indicate that Ce:GdYAG CPs is a promising candidate for automotive lighting and high-speed rail lighting.
High-efficiency coupling of single quantum emitters into hole-tailored nanofibers
Authors: Wang Xin , Zhang Pengfei , Li Gang , Zhang Tiancai
Published: March 2021

We propose a scheme to enhance the coupling efficiency of photons from a single quantum emitter into a hole-tailored nanofiber. The single quantum emitter is positioned inside a circular hole etched along the radial axis of the nanofiber. The coupling efficiency can be effectively enhanced and is twice as high as the case in which only an intact nanofiber without the hole is used. The effective enhancement independent of a cavity can avoid the selection of a single emitter for the specific wavelength, which means a broad operating wavelength range. Numerical simulations are performed to optimize the coupling efficiency by setting appropriate diameters of the nanofiber and the hole. The simulation results show that the coupling efficiency can reach 62.8% when the single quantum emitter with azimuthal polarization (x direction) is at a position 200 nm from the middle of the hole along the hole-axial direction. The diameters of the nanofiber and the hole are 800 nm and 400 nm, respectively, while the wavelength of the single quantum emitter is 852 nm. Hole-tailored nanofibers have a simple configuration and are easy to fabricate and integrate with other micro/nanophotonic structures; this fiber structure has wide application prospects in quantum information processing and quantum precision measurement.
Mid-infrared homodyne balanced detector for quantum light characterization
Authors: Gabbrielli Tecla , Cappelli Francesco , Bruno Natalia , Corrias Nicola , Borri Simone , De Natale Paolo , Zavatta Alessandro
Published: March 2021

We present the characterization of a novel balanced homodyne detector operating in the mid-infrared. The challenging task of revealing non-classicality in mid-infrared light, e. g. in quantum cascade lasers emission, requires a high-performance detection system. Through the intensity noise power spectral density analysis of the differential signal coming from the incident radiation, we show that our setup is shot-noise limited. We discuss the experimental results with a view to possible applications to quantum technologies, such as free-space quantum communication.
Experimental optimal generation of hybrid entangled states in photonic quantum walks
Authors: Tao Si-Jing , Wang Qin-Qin , Chen Zhe , Pan Wei-Wei , Yu Shang , Chen Geng , Xu Xiao-Ye , Han Yong-Jian , Li Chuan-Feng , Guo Guang-Can
Published: March 2021

While the existence of disorders is commonly believed to weaken the
unique properties of quantum systems, recent progress has predicted
that it can exhibit a counterintuitive enhanced effect on the behavior
of entanglement generation, which is even independent of the chosen
initial conditions and physical platforms. However, to achieve a
maximally entangled state in such disordered quantum systems, the key
limitation of this is the scarcity of an infinite coherence time,
which makes its experimental realization challenging. Here, we
experimentally investigate the entanglement entropy dynamics in a
photonic quantum walk with disorders in time. Through the
incorporation of a classic optimization algorithm, we experimentally
demonstrate that such disordered systems can relax to a
high-entanglement hybrid state at any given time step. Moreover, this
prominent entangling ability is universal for a wide variety of
initial conditions. Our results may inspire achieving a
well-controlled entanglement generator for quantum computation and
information tasks.
Towards the elimination of leprosy in Yunnan, China: A time-series analysis of surveillance data
Authors: Shui Tie-Jun , Long Heng , Xiong Li , Zhang Xiao-hong , He Jun , Chen Xiaohua
Published: March 2021

Background

This study reviews the progress of leprosy elimination in Yunnan, China, over the past 30 years and identifies the challenges for the next stage of the program.

Methodology/Principal findings

Data were collected from the Leprosy Management Information System in China (LEPMIS). The progress made in the elimination of leprosy between 1990 and 2019 was measured. We defined two time periods, time period 1 (1990–2003) and time period 2 (2004–2019), because multidrug therapy (MDT) was launched for the treatment of leprosy in 1990 and a special fund from the central government was established for leprosy in 2004. During the past 30 years, the number of newly detected leprosy patients in Yunnan has steadily declined. In total, 703 newly detected leprosy patients were reported in 1990, and 353 and 136 cases were reported at the end of 2003 and 2019, respectively. At the end of 1990, 90.7% (117/129) of counties in Yunnan Province were identified as leprosy-endemic counties (>1 case per 100,000 population). By the end of 2003 and 2019, 39.3% (46/117) and 85.5% (100/117) of the leprosy-endemic counties, respectively, had dropped below the elimination threshold. The main challenges are the remaining leprosy-endemic counties, the high rate of cases with a contact history, insufficient early detection, and leprosy cases resulting in physical disability.

Conclusions/Significance

A multifaceted strategy for leprosy elimination in Yunnan Province has been successfully implemented, and remarkable progress has been made in the elimination of leprosy in this area. The priorities for leprosy elimination in the next stage are securing sustainable support and investment from the government, establishing an effective surveillance system, ensuring prompt early detection, providing treatment with MDT, preventing transmission of M. leprae, preventing disability, providing health education, and preventing recurrence of the epidemic situation of leprosy.
Gender disparity in cases enrolled in clinical trials of visceral leishmaniasis: A systematic review and meta-analysis
Authors: Dahal Prabin , Singh-Phulgenda Sauman , Olliaro Piero L. , Guerin Philippe J.
Published: March 2021

Background

A higher caseload of visceral leishmaniasis (VL) has been observed among males in community-based surveys. We carried out this review to investigate how the observed disparity in gender distribution is reflected in clinical trials of antileishmanial therapies.

Methods

We identified relevant studies by searching a database of all published clinical trials in VL from 1980 through 2019 indexed in the Infectious Diseases Data Observatory (IDDO) VL clinical trials library. The proportion of male participants enrolled in studies eligible for inclusion in this review were extracted and combined using random effects meta-analysis of proportion. Results were expressed as percentages and presented with respective 95% confidence intervals (95% CIs). Heterogeneity was quantified using I2 statistics and sub-group meta-analyses were carried out to explore the sources of heterogeneity.

Results

We identified 135 published studies (1980–2019; 32,177 patients) with 68.0% [95% CI: 65.9%–70.0%; I2 = 92.6%] of the enrolled participants being males. The corresponding estimates were 67.6% [95% CI: 65.5%–69.7%; n = 91 trials; I2 = 90.5%; 24,218 patients] in studies conducted in the Indian sub-continent and 74.1% [95% CI: 68.4%–79.1%; n = 24 trials; I2 = 94.4%; 6,716 patients] in studies from Eastern Africa. The proportion of male participants was 57.9% [95% CI: 54.2%–61.5%] in studies enrolling children aged <15 years, 78.2% [95% CI: 66.0%–86.9%] in studies that enrolled adults (≥15 years), and 68.1% [95% CI: 65.9%–70.0%] in studies that enrolled patients of all ages. There was a trend for decreased proportions of males enrolled over time: 77.1% [95% CI: 70.2%–82.8%; 1356 patients] in studies published prior to the 1990s whereas 64.3% [95% CI: 60.3%–68.2%; 15,611 patients] in studies published on or after 2010. In studies that allowed the inclusion of patients with HIV co-infections, 76.5% [95% CI: 63.8%–85.9%; 5,123 patients] were males and the corresponding estimate was 64.0% [95% CI: 61.4%–66.5% 17,500 patients] in studies which excluded patients with HIV co-infections.

Conclusions

Two-thirds of the participants enrolled in clinical studies in VL conducted in the past 40 years were males, though the imbalance was less in children and in more recent trials. VL treatment guidelines are informed by the knowledge of treatment outcomes from a population that is heavily skewed towards adult males. Investigators planning future studies should consider this fact and ensure approaches for more gender-balanced inclusion.
Knowledge of medical professionals, their practices, and their attitudes toward traditional Chinese medicine for the prevention and treatment of coronavirus disease 2019: A survey in Sichuan, China
Authors: Pu Jing , Mei He , Lei Li , Li Daiwen , Zhao Jiekun , Li Bin , Wang Haiyan , Ma Ying , Du Xiao Bo
Published: March 2021

This study aimed to investigate the knowledge, practices, and attitudes of medical professionals toward Traditional Chinese Medicine (TCM) for the prevention and treatment of coronavirus disease 2019 (COVID-19). All 401 medical professionals were surveyed using an anonymous with an investigator using the Questionnaire star APP. The participants answered 14 questions; of the 401 participants, 55.2% agreed with the statement “TCM can be used for the prevention and treatment of COVID-19,” 40.4% remained neutral, and 4.4% disagreed. Moreover, 75.3% agreed with the statement “There is no specific drug for COVID-19,” 67% agreed with the statement “TCM can develop immunity to COVID-19” and 62.1% agreed with “TCM can alleviate the symptoms of patients with COVID-19.” Meanwhile, 69.1% were aware that TCM has been recommended for COVID-19 by the National Health Commission of the People’s Republic of China. Regarding the selection of sources of knowledge on whether “TCM can be used for the prevention and treatment of COVID-19,” There were 277, 123, 82, 369, and 17 participants selected sources from “Hospital training,” “Academic journals,” “Academic Conferences,” “Social media platforms (such as WeChat)” and “Others,” respectively. Further, 358 participants will take TCM for the prevention of COVID-19. Multiple logistic regression analysis showed that age, major and received TCM treatment within the last five years were independent factors affecting the participants’ attitudes. In the absence of specific drugs for COVID-19, more than half of the participants agreed that TCM could be used for the prevention and treatment of COVID-19 and most participants are willing to take TCM to prevent COVID-19, although unsure about its effectiveness. The main information sources on TCM for the treatment and prevention of COVID-19 were social platforms and hospital training.
Trees and their seed networks: The social dynamics of urban fruit trees and implications for genetic diversity
Authors: Rimlinger Aurore , Avana Marie-Louise , Awono Abdon , Chakocha Armel , Gakwavu Alexis , Lemoine Taïna , Marie Lison , Mboujda Franca , Vigouroux Yves , Johnson Vincent , Vinceti Barbara , Carrière Stéphanie M. , Duminil Jérôme
Published: March 2021

Trees are a traditional component of urban spaces where they provide ecosystem services critical to urban wellbeing. In the Tropics, urban trees’ seed origins have rarely been characterized. Yet, understanding the social dynamics linked to tree planting is critical given their influence on the distribution of associated genetic diversity. This study examines elements of these dynamics (seed exchange networks) in an emblematic indigenous fruit tree species from Central Africa, the African plum tree (Dacryodes edulis, Burseraceae), within the urban context of Yaoundé. We further evaluate the consequences of these social dynamics on the distribution of the genetic diversity of the species in the city. Urban trees were planted predominantly using seeds sourced from outside the city, resulting in a level of genetic diversity as high in Yaoundé as in a whole region of production of the species. Debating the different drivers that foster the genetic diversity in planted urban trees, the study argues that cities and urban dwellers can unconsciously act as effective guardians of indigenous tree genetic diversity.
Progress and challenges in potential access to oral health primary care services in Brazil: A population-based panel study with latent transition analysis
Authors: Ribeiro Ana Graziela Araujo , Martins Rafiza Félix Marão , Vissoci João Ricardo Nickenig , da Silva Núbia Cristina , Rocha Thiago Augusto Hernandes , Queiroz Rejane Christine de Sousa , Tonello Aline Sampieri , Staton Catherine A. , Facchini Luiz Augusto , Thomaz Erika Bárbara Abreu Fonseca
Published: March 2021

Objective

Compared indicators of potential access to oral health services sought in two cycles of the Program for Improvement of Access and Quality of Primary Care (PMAQ-AB), verifying whether the program generated changes in access to oral health services.

Methods

Transitional analysis of latent classes was used to analyze two cross-sections of the external evaluation of the PMAQ-AB (Cycle I: 2011–2012 and Cycle II: 2013–2014), identifying completeness classes for a structure and work process related to oral health. Consider three indicators of structure (presence of a dental surgeon, existence of a dental office and operating at minimum hours) and five of the work process (scheduling every day of the week, home visits, basic dental procedures, scheduling for spontaneous demand and continuation of treatment). Choropleth maps and hotspots were made.

Results

The proportion of elements that had one or more dentist (CD), dental office and operated at minimum hours varied from 65.56% to 67.13 between the two cycles of the PMAQ-AB. The number of teams that made appointments every day of the week increased 8.7% and those that made home visits varied from 44.51% to 52.88%. The reduction in the number of teams that reported guaranteeing the agenda for accommodating spontaneous demand, varying from 62.41% to 60.11% and in the continuity of treatment, varying from 63.41% to 61.11%. For the structure of health requirements, the predominant completeness profile was "Best completeness" in both cycles, comprising 71.0% of the sets at time 1 and 67.0% at time 2. The proportion of teams with "Best completeness" increased by 89.1%, the one with "Worst completeness" increased by 20%, while those with "Average completeness" decreased by 66.3%.

Conclusion

We identified positive changes in the indicators of potential access to oral health services, expanding the users’ ability to use them. However, some access attributes remain unsatisfactory, with organizational barriers persisting.
Gut microbiota profiles in diarrheic patients with co-occurrence of Clostridioides difficile and Blastocystis
Authors: Vega Laura , Herrera Giovanny , Muñoz Marina , Patarroyo Manuel A. , Maloney Jenny G. , Santín Monica , Ramírez Juan David
Published: March 2021

Blastocystis and Clostridioides difficile co-occurrence is considered a rare event since the colonization by Blastocystis is prevented under a decrease in beneficial bacteria in the microbiota when there is C. difficile infection (CDI). This scenario has been reported once, but no information on the gut microbiota profiling is available. The present study is motivated by knowing which members of the microbiota can be found in this rare scenario and how this co-occurrence may impact the abundance of other bacteria, eukaryotes or archaea present in the gut microbiota. This study aimed to describe the bacterial and eukaryotic communities using amplicon-based sequencing of the 16S- and 18S-rRNA regions of three patient groups: (1) Blastocystis and C. difficile infection (B+/C+, n = 31), (2) C. difficile infection only (B˗/C+, n = 44), and (3) without Blastocystis or C. difficile (B˗/C˗, n = 40). Blastocystis was subtyped using amplicon-based sequencing of the 18S-rRNA gene, revealing circulation of subtypes ST1 (43.4%), ST3 (35.85%) and ST5 (20.75%) among the study population. We found that B+/C+ patients had a higher abundance of some beneficial bacteria (such as butyrate producers or bacteria with anti-inflammatory properties) compared with non-Blastocystis-colonized patients, which may suggest a shift towards an increase in beneficial bacteria when Blastocystis colonizes patients with CDI. Regarding eukaryotic communities, statistical differences in the abundance of some eukaryotic genera between the study groups were not observed. Thus, this study provides preliminary descriptive information of a potential microbiota profiling of differential presence by Blastocystis and C. difficile.
Impact of pulmonary rehabilitation in sleep in COPD patients measured by actigraphy
Authors: Thapamagar Suman B. , Ellstrom Kathleen , Anholm James D. , Fargo Ramiz A. , Dandamudi Nagamani
Published: March 2021

Introduction

Chronic obstructive pulmonary disease (COPD) patients have poor sleep quality, longer time to sleep onset and frequent nocturnal awakenings. Poor sleep quality in COPD is associated with poor quality of life (QoL), increased exacerbations and increased mortality. Pulmonary rehabilitation (PR) improves functional status and QoL in COPD but effects on sleep are unclear. PR improves subjective sleep quality but there is paucity of objective actigraphy data. We hypothesized that actigraphy would demonstrate subjective and objective improvement in sleep following PR. Paired comparisons (t-test or Wilcoxon-signed-rank test) were performed before and after PR data on all variables.

Methods

This retrospective study of COPD patients undergoing PR utilized actigraphy watch recordings before and after 8-weeks of PR to assess changes in sleep variables including total time in bed (TBT), total sleep time (TST), sleep onset latency (SOL), sleep efficiency (SE), wakefulness after sleep onset (WASO) and total nocturnal awakenings. A change in Pittsburg Sleep Quality Index (PSQI) was a secondary outcome. PSQI was performed before and after PR.

Results

Sixty-nine patients were included in the final analysis. Most participants were male (97%), non-obese (median BMI 27.5, IQR 24.3 to 32.4 kg/m2) with an average age of 69 ± 8 years and 71% had severe COPD (GOLD stage 3 or 4). Prevalence of poor sleep quality (PSQI ≥5) was 86%. Paired comparisons did not show improvement in actigraphic sleep parameters following 8-weeks PR despite improvements in 6-min-walk distance (6MWD, mean improvement 54 m, 95% CI 34 m to 74 m, p<0.0001) and St. George’s Respiratory Questionnaire scores (SGRQ, mean improvement 7.7 points, 95% CI 5.2 to 10.2, p<0.0001). Stratified analysis of all sleep variables by severity of COPD, BMI, mood, mental status, 6-MWD and SGRQ did not show significant improvement after PR. In Veterans with poor sleep quality (PSQI ≥ 5), PR improved subjective sleep quality (PSQI, mean difference 0.79, 95% CI 0.07 to 1.40, p = 0.03).

Conclusions

Pulmonary rehabilitation improved subjective sleep quality in Veterans who had poor sleep quality at the beginning of the PR but did not improve objective sleep parameters by actigraphy. Our findings highlight the complex interactions among COPD, sleep and exercise.
19-(Benzyloxy)-19-oxojolkinolide B (19-BJB), an ent-abietane diterpene diepoxide, inhibits the growth of bladder cancer T24 cells through DNA damage
Authors: Wang Ke , Yang Juan-Cheng , Jang Yeong-Jiunn , Chen Guan-Yu , Zhang Ya-Jing , Dai Yun-Hao , Zhang Da-Yong , Wu Yang-Chang
Published: March 2021

Diterpenoids jolkinolide A and B, were first isolated from Euphorbia fischeriana. In our previous research, 19-(Benzyloxy)-19-oxojolkinolide B (19-BJB), a derivative of jolkinolides, was synthesized as a novel ent -abietane diterpene diepoxide. In this study, 19-BJB showed strong in vitro activity against bladder cancer cell lines. DNA damage which was observed through the interaction of 19-BJB with nucleotide chains and affected DNA repair resulted in the activation of checkpoint kinase 1 (Chk1) and checkpoint kinase 2 (Chk2) in bladder cancer cell lines. In vivo testing in nude mice also proved that 19-BJB revealed a potential inhibitory effect on tumor growth. Additionally, the 3D-QSAR models of jolkinolides were established. Briefly, we proved that 19-BJB could potentially be used as a drug to inhibit the growth of bladder tumor.
Determinants of birth asphyxia among newborns delivered in public hospitals of West Shoa Zone, Central Ethiopia: A case-control study
Authors: Kune Guta , Oljira Habtamu , Wakgari Negash , Zerihun Ebisa , Aboma Mecha
Published: March 2021

Birth asphyxia is one of the leading causes of death in low and middle-income countries and the prominent cause of neonatal mortality in Ethiopia. Early detection and managing its determinants would change the burden of birth asphyxia. Thus, this study identified determinants of birth asphyxia among newborns delivered in public hospitals of West Shoa Zone, central Ethiopia. A hospital-based unmatched case-control study was conducted from May to July 2020. Cases were newborns with APGAR (appearance, pulse, grimaces, activity, and respiration) score of <7 at first and fifth minute of birth and controls were newborns with APGAR score of ≥ 7 at first and fifth minute of birth. All newborns with birth asphyxia during the study period were included in the study while; two comparable controls were selected consecutively after each birth asphyxia case. A pre-tested and structured questionnaire was used to collect maternal socio-demographic and antepartum characteristics. The pre-tested checklist was used to retrieve intrapartum and fetal related factors from both cases and controls. The collected data were entered using Epi-Info and analyzed by SPSS. Bi-variable logistic regression analysis was done to identify the association between each independent variable with the outcome variable. Adjusted odds ratio (AOR) with a 95% CI and a p-value of <0.05 was used to identify determinants of birth asphyxia. In this study, prolonged labor (AOR = 4.15, 95% CI: 1.55, 11.06), breech presentation (AOR = 5.13, 95% CI: 1.99, 13.21), caesarean section delivery (AOR = 3.67, 95% CI: 1.31, 10.23), vaginal assisted delivery (AOR = 5.69, 95% CI: 2.17, 14.91), not use partograph (AOR = 3.36, 95% CI: 1.45, 7.84), and low birth weight (AOR = 3.74, 95% CI:1.49, 9.38) had higher odds of birth asphyxia. Prolonged labor, breech presentation, caesarean and vaginal assisted delivery, fails to use partograph and low birth weights were the determinants of birth asphyxia. Thus, health care providers should follow the progress of labor with partograph to early identify prolonged labor, breech presentation and determine the mode of delivery that would lower the burden of birth asphyxia.
Stroke risk in arthritis: A systematic review and meta-analysis of cohort studies
Authors: Liu Wei , Ma Wei , Liu Hua , Li Chunyan , Zhang Yangwei , Liu Jie , Liang Yu , Zhang Sijia , Wu Zhen , Zang Chenghao , Guo Jianhui , Li Liyan
Published: March 2021

Background and objective

Stroke is a major contributor to the global burden of disease. Although numerous modifiable risk factors (RF) for stroke have been identified, some remain unexplained. Increasing studies have investigated stroke risk in arthritis, but their results are inconsistent. We aimed to synthesize, quantify, and compare the risk of stroke for the major types of arthritis in cohort studies by using a systematic review and meta-analysis approach.

Methods

We searched Chinese and English databases to identify relevant studies from inception to April 30, 2020. Only studies adjusting at least for age and sex were included. We calculated pooled effect estimates for relative risk (RR) and 95% confidence interval (CI) and identified potential sources of heterogeneity and publication bias.

Results

A total of 1,348 articles were retrieved, and after an preliminary screening of titles and abstracts, 69 were reviewed for full text, and finally, 32 met the criteria for meta-analysis. Stroke risk in arthritis was significantly increased in studies adjusting for age and sex (RR = 1.36, 95% CI: 1.27–1.46) and for at least one traditional risk factor (RR = 1.40, 95% CI: 1.28–1.54). The results of studies stratified by stroke subtype were consistent with the main finding (ischemic stroke: RR = 1.53, 95% CI: 1.32–1.78; hemorrhagic stroke: RR = 1.45, 95% CI: 1.15–1.84). In subgroup analysis by arthritis type, stroke risk was significantly increased in rheumatoid arthritis (RR = 1.38, 95% CI: 1.29–1.48), ankylosing spondylitis (RR = 1.49, 95% CI: 1.25–1.77), psoriatic arthritis (RR = 1.33, 95% CI: 1.22–1.45), and gout (RR = 1.40, 95% CI: 1.13–1.73) but not osteoarthritis (RR = 1.03, 95% CI: 0.91–1.16). Age and sex subgroup analyses indicated that stroke risk was similar by sex (women: RR = 1.47, 95% CI: 1.31–1.66; men: RR = 1.44, 95% CI: 1.28–1.61); risk was higher with younger age (<45 years) (RR = 1.46, 95% CI: 1.17–1.82) than older age (≥65 years) (RR = 1.17, 95% CI: 1.08–1.26).

Conclusions

Stroke risk was increased in multiple arthritis and similar between ischemic and hemorrhagic stroke. Young patients with arthritis had the highest risk.
Improving the precision of modeling the incidence of hemorrhagic fever with renal syndrome in mainland China with an ensemble machine learning approach
Authors: Ye Guo-hua , Alim Mirxat , Guan Peng , Huang De-sheng , Zhou Bao-sen , Wu Wei
Published: March 2021

Objective

Hemorrhagic fever with renal syndrome (HFRS), one of the main public health concerns in mainland China, is a group of clinically similar diseases caused by hantaviruses. Statistical approaches have always been leveraged to forecast the future incidence rates of certain infectious diseases to effectively control their prevalence and outbreak potential. Compared to the use of one base model, model stacking can often produce better forecasting results. In this study, we fitted the monthly reported cases of HFRS in mainland China with a model stacking approach and compared its forecasting performance with those of five base models.

Method

We fitted the monthly reported cases of HFRS ranging from January 2004 to June 2019 in mainland China with an autoregressive integrated moving average (ARIMA) model; the Holt-Winter (HW) method, seasonal decomposition of the time series by LOESS (STL); a neural network autoregressive (NNAR) model; and an exponential smoothing state space model with a Box-Cox transformation; ARMA errors; and trend and seasonal components (TBATS), and we combined the forecasting results with the inverse rank approach. The forecasting performance was estimated based on several accuracy criteria for model prediction, including the mean absolute percentage error (MAPE), root-mean-squared error (RMSE) and mean absolute error (MAE).

Result

There was a slight downward trend and obvious seasonal periodicity inherent in the time series data for HFRS in mainland China. The model stacking method was selected as the best approach with the best performance in terms of both fitting (RMSE 128.19, MAE 85.63, MAPE 8.18) and prediction (RMSE 151.86, MAE 118.28, MAPE 13.16).

Conclusion

The results showed that model stacking by using the optimal mean forecasting weight of the five abovementioned models achieved the best performance in terms of predicting HFRS one year into the future. This study has corroborated the conclusion that model stacking is an easy way to enhance prediction accuracy when modeling HFRS.
Composite core set construction and diversity analysis of Iranian walnut germplasm using molecular markers and phenotypic traits
Authors: Mahmoodi Razieh , Dadpour Mohammad Reza , Hassani Darab , Zeinalabedini Mehrshad , Vendramin Elisa , Leslie Charles A.
Published: March 2021

Iran is a center of origin and diversity for walnuts (Juglans regia L.) with very good potential for breeding purposes. The rich germplasm available, creates an opportunity for study and selection of the diverse walnut genotypes. In this study, the population structure of 104 Persian walnut accessions was assessed using AFLP markers in combination with phenotypic variability of 17 and 18 qualitative and quantitative traits respetively. The primers E-TG/M-CAG, with high values of number of polymorphic bands, polymorphic information content, marker index and Shannon’s diversity index, were the most effective in detecting genetic variation within the walnut germplasm. Multivariate analysis of variance indicated 93.98% of the genetic variability was between individuals, while 6.32% of variation was among populations. A relatively new technique, an advanced maximization strategy with a heuristic approach, was deployed to develop the core collection. Initially, three independent core collections (CC1–CC3) were created using phenotypic data and molecular markers. The three core collections (CC1–CC3) were then merged to generate a composite core collection (CC4). The mean difference percentage, variance difference percentage, variable rate of coefficient of variance percentage, coincidence rate of range percentage, Shannon’s diversity index, and Nei’s gene diversity were employed for comparative analysis. The CC4 with 46 accessions represented the complete range of phenotypic and genetic variability. This study is the first report describing development of a core collection in walnut using molecular marker data in combination with phenotypic values. The construction of core collection could facilitate the work for identification of genetic determinants of trait variability and aid effective utilization of diversity caused by outcrossing, in walnut breeding programs.
Molecular dynamics study on characteristics of reflection and condensation molecules at vapor–liquid equilibrium state
Authors: Tabe Hirofumi , Kobayashi Kazumichi , Fujii Hiroyuki , Watanabe Masao
Published: March 2021

The kinetic boundary condition (KBC) represents the evaporation or condensation of molecules at the vapor–liquid interface for molecular gas dynamics (MGD). When constructing the KBC, it is necessary to classify molecular motions into evaporation, condensation, and reflection in molecular-scale simulation methods. Recently, a method that involves setting the vapor boundary and liquid boundary has been used for classifying molecules. The position of the vapor boundary is related to the position where the KBC is applied in MGD analyses, whereas that of the liquid boundary has not been uniquely determined. Therefore, in this study, we conducted molecular dynamics simulations to discuss the position of the liquid boundary for the construction of KBCs. We obtained some variables that characterize molecular motions such as the positions that the molecules reached and the time they stayed in the vicinity of the interface. Based on the characteristics of the molecules found from these variables, we investigated the valid position of the liquid boundary. We also conducted an investigation on the relationship between the condensation coefficient and the molecular incident velocity from the vapor phase to the liquid phase. The dependence of the condensation coefficient on the incident velocity of molecules was confirmed, and the value of the condensation coefficient becomes small in the low-incident-velocity range. Furthermore, we found that the condensation coefficient in the non-equilibrium state shows almost the same value as that in the equilibrium state, although the corresponding velocity distribution functions of the incident velocity significantly differ from each other.
Accurate point-of-care serology tests for COVID-19
Authors: Schuler Charles F. , Gherasim Carmen , O’Shea Kelly , Manthei David M. , Chen Jesse , Giacherio Don , Troost Jonathan P. , Baldwin James L. , Baker James R.
Published: March 2021

Background

As COVID-19 vaccines become available, screening individuals for prior COVID-19 infection and vaccine response in point-of-care (POC) settings has renewed interest. We prospectively screened at-risk individuals for SARS-CoV-2 spike and nucleocapsid protein antibodies in a POC setting to determine if it was a feasible method to identify antibody from prior infection.

Methods

Three EUA-approved lateral flow antibody assays were performed on POC finger-stick blood and compared with serum and a CLIA nucleocapsid antibody immunoassay. Variables including antibody class, time since PCR, and the assay antigen used were evaluated.

Results

512 subjects enrolled, of which 104 had a COVID-19 history and positive PCR. Only three PCR-positive subjects required hospitalization, with one requiring mechanical ventilation. The POC results correlated well with the immunoassay (93–97% sensitivity) and using serum did not improve the sensitivity or specificity.

Conclusions

Finger-stick, POC COVID-19 antibody testing was highly effective in identifying antibody resulting from prior infections in mildly symptomatic subjects. Using high-complexity serum immunoassays did not improve the screening outcome. Almost all individuals with COVID-19 infection produced detectable antibodies to the virus. POC antibody testing is useful as a screen for prior COVID-19 infection, and should be useful in assessing vaccine response.
Dynamic interplay between the co-opted Fis1 mitochondrial fission protein and membrane contact site proteins in supporting tombusvirus replication
Authors: Lin Wenwu , Feng Zhike , Prasanth K. Reddisiva , Liu Yuyan , Nagy Peter D.
Published: March 2021

Plus-stranded RNA viruses have limited coding capacity and have to co-opt numerous pro-viral host factors to support their replication. Many of the co-opted host factors support the biogenesis of the viral replication compartments and the formation of viral replicase complexes on subverted subcellular membrane surfaces. Tomato bushy stunt virus (TBSV) exploits peroxisomal membranes, whereas the closely-related carnation Italian ringspot virus (CIRV) hijacks the outer membranes of mitochondria. How these organellar membranes can be recruited into pro-viral roles is not completely understood. Here, we show that the highly conserved Fis1 mitochondrial fission protein is co-opted by both TBSV and CIRV via direct interactions with the p33/p36 replication proteins. Deletion ofFIS1in yeast or knockdown of the homologous Fis1 in plants inhibits tombusvirus replication. Instead of the canonical function in mitochondrial fission and peroxisome division, the tethering function of Fis1 is exploited by tombusviruses to facilitate the subversion of membrane contact site (MCS) proteins and peroxisomal/mitochondrial membranes for the biogenesis of the replication compartment. We propose that the dynamic interactions of Fis1 with MCS proteins, such as the ER resident VAP tethering proteins, Sac1 PI4P phosphatase and the cytosolic OSBP-like oxysterol-binding proteins, promote the formation and facilitate the stabilization of virus-induced vMCSs, which enrich sterols within the replication compartment. We show that this novel function of Fis1 is exploited by tombusviruses to build nuclease-insensitive viral replication compartment.