bluuebunny/crossref_metadata_2025 huggingface dataset:
Polarization-independent 2×2 high diffraction efficiency beam splitter based on two-dimensional grating
Authors: Zhou Bin , Jia Wei , Xiang Changcheng , Xie Yongfang , Wang Jin , Jin Ge , Wang Yihan , Zhou Changhe
Published: September 2021

Better performances of two-dimensional (2D) grating are required recently, such as polarization independence, high efficiency, wide bandwidth and so forth. In this paper, we propose a 2×2 2D silver cylindrical array grating with excellent polarization-independent high diffraction efficiency (DE) over communication band for beam splitting. The grating was calculated by rigorous coupled wave analysis (RCWA) and can achieve over 24% DE of four first diffraction orders at 1550 nm with nonuniformity of 1.43% in both transverse electric (TE) and transverse magnetic (TM) polarizations, which is a significant improvement over previous reports. The holographic exposure technology, wet chemical development process and electron beam evaporation were used to fabricate the 2D grating. The correctness and accuracy of the calculation are fully verified with the measurement result of fabricated grating. Excellent performances of the 2D splitter we proposed will have great potential for applications in optical communication, semiconductor manufacturing and displacement measurement.
Imaging performance of an ultra-precision machining-based Fresnel lens in ophthalmic devices
Authors: Vu Van Truong , Ui Hasan Syed Azkar , Youn Hongseok , Park Youngdurk , Lee Hocheol
Published: September 2021

This study aims to resolve the trade-off between the constraints and capabilities of ultra-precision machining to achieve ophthalmic Fresnel lenses. A general Fresnel lens pattern has a narrow variable pitch and curved grooves. However, we obviate the limitations of the tool nose radius constraint and the long tool path via ultra-precision machining of the modified Fresnel lens, ensuring a constant pitch of 0.1 mm and varying the height of straight grooves from 0 to 11 µm. Photorealistic raytracing visualization and MTF simulation verified the compatibility of the lens pattern with human perception sensitivity. Copper-coated mold was fabricated using a diamond tool with a tool nose radius of 5 µm. The replicated flexible Fresnel lens demonstrated a relative MTF imaging performance of 89.1% and was attached to the goggles for the qualitative assessment. The proposed Fresnel lens design and fabrication approach can be extended to applications in the visual and infrared ranges as well.
Two-photon-absorption enhanced terahertz generation from KTP optically pumped in the visible-to-UV range
Authors: Zhai Dongwei , Hérault Emilie , Garet Frédéric , Pasiskevicius Valdas , Laurell Fredrik , Coutaz Jean-Louis
Published: September 2021

By generating terahertz pulses in KTP crystals through optical rectification with a pump photon energy varying from below to above the bandgap, we observe a peak of the THz signal at the bandgap energy but also a second one around half the bandgap. This later one is attributed to a two-photon absorption enhanced nonlinearity, which is validated by the similarity of the two-photon absorption coefficient and THz peak amplitude data versus the pump photon energy. A careful analysis of the KTP sample absorption spectral dependence nearby the bandgap demonstrates that KTP is an indirect bandgap crystal, whose absorption below the bandgap involves emission of a phonon related to the symmetric Ti-O stretching vibration, i.e. the ν1 (A1g) mode.
Low spatial complexity adaptive artificial neural network post-equalization algorithms in MIMO visible light communication systems
Authors: Zhao Yiheng , Zou Peng , He Zhixue , Li Ziwei , Chi Nan
Published: September 2021

In this paper, we experimentally propose a feasible and low spatial complexity adaptive artificial neural network (AANN) post-equalization algorithm in MIMO visible light communication (VLC) systems. By introducing the power ratio and the MIMO least mean square (MIMO-LMS) post-equalization algorithm into the structure design process of the artificial neural network (ANN) post-equalization algorithm, we reduced the spatial complexity of the post-ANN equalization algorithm to less than 10%. At the same time, the bit error rate (BER) performance of AANNs did not decrease. Finally, we achieved a data rate of 2.1Gbps in the AANN equalized 16QAM superposition coding modulation (SCM) and carrier-less amplitude-phase (CAP) single-receiver MIMO (SR-MIMO) VLC system.
Ground-based high-resolution remote sensing of sulphur hexafluoride (SF6) over Hefei, China: characterization, optical misalignment, influence, and variability
Authors: Yin Hao , Sun Youwen , Wang Wei , Shan Changgong , Tian Yuan , Liu Cheng
Published: September 2021

It is a challenge to retrieve atmospheric sulphur hexafluoride (SF6) with high resolution solar spectra because it has only one single retrieval micro window and has interfered with many factors in the retrieval. Optical misalignment is one of the key factors that affect the accuracy of SF6 retrieval. In this study, we first present a long term time series of the SF6 total column over Hefei, China, between January 2017 and December 2020, retrieved by mid-infrared (MIR) solar spectra recorded by ground-based high-resolution Fourier transform infrared spectroscopy (FTIR). The sensitivities of the total column, root mean square of fitting residual (RMS), total error budgets, degrees of freedom for signal (DOFs), and vertical mixing ratio (VMR) profile with respect to different levels of optical misalignment for SF6 retrieval were assessed. The SF6 total column is sensitive to optical misalignment. In order to avoid inconsistencies in the total column due to optical misalignment, we use the true instrumental line shape (ILS) derived from regular low-pressure HBr cell measurements to retrieve the time series of SF6. The total column of SF6 over Hefei presents strong seasonal dependent features. The maximum monthly average value of (3.57 ± 0.21) × 1014 molecules*cm-2 in summer is (7.60 ± 3.50) × 1013 molecules*cm-2 (21.29 ± 9.80) % higher than the minimum monthly average value of (2.81 ± 0.14) × 1014 molecules*cm-2 in winter. The annual average SF6 total columns in 2017-2020 are (3.02 ± 0.17), (3.50 ± 0.18), (3.25 ± 0.18), and (3.08 ± 0.16) × 1014 molecules*cm-2, respectively, which are close to each other. It indicates that SF6 total column over Hefei is stable in the past four years. Our study can improve the current understanding for ground-based high-resolution remote sensing of SF6 and also contribute to generate new reliable remote sensing data in this sparsely monitored region for investigations of climate change, global warming, and air pollution.
Compressed-sensing fiber-optic white light interferometry
Authors: Liu Qiang , Li Shi-Min , Zhou Da-Peng , Jing Zhenguo , Peng Wei
Published: September 2021

In this Letter, we propose a dynamic fiber-optic white light interferometry (WLI) based on the compressed-sensing (CS) principle. The time-varying interference spectra of a Fabry–Perot cavity under vibration are considered as a two-dimensional (2D) signal with respect to both laser wavelength and time, which can be compressively sampled using a programmable semiconductor laser source during the measurement process. After CS reconstruction, the spectrum acquisition rate is equal to the random wavelength modulation rate, up to 10 MHz in this Letter, providing an attractive alternative to laser-based dynamic interferometry. Numerical simulations and nanometer-scale vibration experiments verify the effectiveness of the scheme.
Ultra-compact polarization-independent 3 dB power splitter in silicon
Authors: Zhang Aoxue , Xia Lipeng , Li Ting , Chang Chang , Zhou Peiji , Xu Xiaochuan , Zou Yi
Published: September 2021

We experimentally demonstrate an ultra-compact polarization-independent 3 dB power splitter on the silicon-on-insulator platform. Subwavelength structure engineering is employed to balance the coupling coefficients of TE and TM polarizations as well as a footprint reduction. The device possesses ultra-compact (

1.2

µ

m

×

2.62

µ

m

) and polarization-independent features with an operating bandwidth over 50 nm (from 1540 to 1590 nm).
Chromosomal neighbourhoods allow identification of organ specific changes in gene expression
Authors: Das Roy Rishi , Hallikas Outi , Christensen Mona M. , Renvoisé Elodie , Jernvall Jukka
Published: September 2021

Although most genes share their chromosomal neighbourhood with other genes, distribution of genes has not been explored in the context of individual organ development; the common focus of developmental biology studies. Because developmental processes are often associated with initially subtle changes in gene expression, here we explored whether neighbouring genes are informative in the identification of differentially expressed genes. First, we quantified the chromosomal neighbourhood patterns of genes having related functional roles in the mammalian genome. Although the majority of protein coding genes have at least five neighbours within 1 Mb window around each gene, very few of these neighbours regulate development of the same organ. Analyses of transcriptomes of developing mouse molar teeth revealed that whereas expression of genes regulating tooth development changes, their neighbouring genes show no marked changes, irrespective of their level of expression. Finally, we test whether inclusion of gene neighbourhood in the analyses of differential expression could provide additional benefits. For the analyses, we developed an algorithm, called DELocal that identifies differentially expressed genes by comparing their expression changes to changes in adjacent genes in their chromosomal regions. Our results show that DELocal removes detection bias towards large changes in expression, thereby allowing identification of even subtle changes in development. Future studies, including the detection of differential expression, may benefit from, and further characterize the significance of gene-gene neighbour relationships.
An assembly-free method of phylogeny reconstruction using short-read sequences from pooled samples without barcodes
Authors: Wong Thomas K. F. , Li Teng , Ranjard Louis , Wu Steven H. , Sukumaran Jeet , Rodrigo Allen G.
Published: September 2021

A current strategy for obtaining haplotype information from several individuals involves short-read sequencing of pooled amplicons, where fragments from each individual is identified by a unique DNA barcode. In this paper, we report a new method to recover the phylogeny of haplotypes from short-read sequences obtained using pooled amplicons from a mixture of individuals, without barcoding. The method, AFPhyloMix, accepts an alignment of the mixture of reads against a reference sequence, obtains the single-nucleotide-polymorphisms (SNP) patterns along the alignment, and constructs the phylogenetic tree according to the SNP patterns. AFPhyloMix adopts a Bayesian inference model to estimate the phylogeny of the haplotypes and their relative abundances, given that the number of haplotypes is known. In our simulations, AFPhyloMix achieved at least 80% accuracy at recovering the phylogenies and relative abundances of the constituent haplotypes, for mixtures with up to 15 haplotypes. AFPhyloMix also worked well on a real data set of kangaroo mitochondrial DNA sequences.
Stochastic model of lignocellulosic material saccharification
Authors: Behle Eric , Raguin Adélaïde
Published: September 2021

The processing of agricultural wastes towards extraction of renewable resources is recently being considered as a promising alternative to conventional biofuel production. The degradation of agricultural residues is a complex chemical process that is currently time intensive and costly. Various pre-treatment methods are being investigated to determine the subsequent modification of the material and the main obstacles in increasing the enzymatic saccharification. In this study, we present a computational model that complements the experimental approaches. We decipher how the three-dimensional structure of the substrate impacts the saccharification dynamics. We model a cell wall microfibril composed of cellulose and surrounded by hemicellulose and lignin, with various relative abundances and arrangements. This substrate is subjected to digestion by different cocktails of well characterized enzymes. The saccharification dynamics is simulated in silico using a stochastic procedure based on a Gillespie algorithm. As we additionally implement a fitting procedure that optimizes the parameters of the simulation runs, we are able to reproduce experimental saccharification time courses for corn stover. Our model highlights the synergistic action of enzymes, and confirms the linear decrease of sugar conversion when either lignin content or crystallinity of the substrate increases. Importantly, we show that considering the crystallinity of cellulose in addition to the substrate composition is essential to interpret experimental saccharification data. Finally, our findings support the hypothesis of xylan being partially crystalline.
Social Innovation For Health Research: Development of the SIFHR Checklist
Authors: Kpokiri Eneyi E. , Chen Elizabeth , Li Jingjing , Payne Sarah , Shrestha Priyanka , Afsana Kaosar , Amazigo Uche , Awor Phyllis , de Lavison Jean-Francois , Khan Saqif , Mier-Alpaño Jana , Ong Alberto , Subhedar Shivani , Wachmuth Isabelle , Cuervo Luis Gabriel , Mehta Kala M. , Halpaap Beatrice , Tucker Joseph D.
Published: September 2021

Background

Social innovations in health are inclusive solutions to address the healthcare delivery gap that meet the needs of end users through a multi-stakeholder, community-engaged process. While social innovations for health have shown promise in closing the healthcare delivery gap, more research is needed to evaluate, scale up, and sustain social innovation. Research checklists can standardize and improve reporting of research findings, promote transparency, and increase replicability of study results and findings.

Methods and findings

The research checklist was developed through a 3-step community-engaged process, including a global open call for ideas, a scoping review, and a 3-round modified Delphi process. The call for entries solicited checklists and related items and was open between November 27, 2019 and February 1, 2020. In addition to the open call submissions and scoping review findings, a 17-item Social Innovation For Health Research (SIFHR) Checklist was developed based on the Template for Intervention Description and Replication (TIDieR) Checklist. The checklist was then refined during 3 rounds of Delphi surveys conducted between May and June 2020. The resulting checklist will facilitate more complete and transparent reporting, increase end-user engagement, and help assess social innovation projects. A limitation of the open call was requiring internet access, which likely discouraged participation of some subgroups.

Conclusions

The SIFHR Checklist will strengthen the reporting of social innovation for health research studies. More research is needed on social innovation for health.
MALDI-TOF mass spectrometry for the identification of freshwater snails from Senegal, including intermediate hosts of schistosomes
Authors: Hamlili Fatima Zohra , Thiam Fatou , Laroche Maureen , Diarra Adama Zan , Doucouré Souleymane , Gaye Papa Mouhamadou , Fall Cheikh Binetou , Faye Babacar , Sokhna Cheikh , Sow Doudou , Parola Philippe
Published: September 2021

Freshwater snails of the genera Biomphalaria, Bulinus, and Oncomelania are intermediate hosts of schistosomes that cause human schistosomiasis, one of the most significant infectious neglected diseases in the world. Identification of freshwater snails is usually based on morphology and potentially DNA-based methods, but these have many drawbacks that hamper their use. MALDI-TOF MS has revolutionised clinical microbiology and has emerged in the medical entomology field. This study aims to evaluate MALDI-TOF MS profiling for the identification of both frozen and ethanol-stored snail species using protein extracts from different body parts. A total of 530 field specimens belonging to nine species (Biomphalaria pfeifferi, Bulinus forskalii, Bulinus senegalensis, Bulinus truncatus, Bulinus globosus, Bellamya unicolor, Cleopatra bulimoides, Lymnaea natalensis, Melanoides tuberculata) and 89 laboratory-reared specimens, including three species (Bi. pfeifferi, Bu. forskalii, Bu. truncatus) were used for this study. For frozen snails, the feet of 127 field and 74 laboratory-reared specimens were used to validate the optimised MALDI-TOF MS protocol. The spectral analysis yielded intra-species reproducibility and inter-species specificity which resulted in the correct identification of all the specimens in blind queries, with log-score values greater than 1.7. In a second step, we demonstrated that MALDI-TOF MS could also be used to identify ethanol-stored snails using proteins extracted from the foot using a specific database including a large number of ethanol preserved specimens. This study shows for the first time that MALDI-TOF MS is a reliable tool for the rapid identification of frozen and ethanol-stored freshwater snails without any malacological expertise.
In vitro culture of freshly isolated Trypanosoma brucei brucei bloodstream forms results in gene copy-number changes
Authors: Mulindwa Julius , Ssentamu Geofrey , Matovu Enock , Kamanyi Marucha Kevin , Aresta-Branco Francisco , Helbig Claudia , Clayton Christine
Published: September 2021

Most researchers who study unicellular eukaryotes work with an extremely limited number of laboratory-adapted isolates that were obtained from the field decades ago, but the effects of passage in laboratory rodents, and adaptation to in vitro culture, have been little studied. For example, the vast majority of studies of Trypanosoma brucei biology have concentrated on just two strains, Lister 427 and EATRO1125, which were taken from the field over half a century ago and have since have undergone innumerable passages in rodents and culture. We here describe two new Trypanosoma brucei brucei strains. MAK65 and MAK98, which have undergone only 3 rodent passages since isolation from Ugandan cattle. High-coverage sequencing revealed that adaptation of the parasites to culture was accompanied by changes in gene copy numbers. T. brucei has so far been considered to be uniformly diploid, but we also found trisomy of chromosome 5 not only in one Lister 427 culture, but also in the MAK98 field isolate. Trisomy of chromosome 6, and increased copies of other chromosome segments, were also seen in established cultured lines. The two new T. brucei strains should be useful to researchers interested in trypanosome differentiation and pathogenicity. Initial results suggested that the two strains have differing infection patterns in rodents. MAK65 is uniformly diploid and grew more reproducibly in bloodstream-form culture than MAK98.
Sensitive and semiquantitative detection of soil-transmitted helminth infection in stool using a recombinase polymerase amplification-based assay
Authors: Cantera Jason L. , White Heather N. , Forrest Matthew S. , Stringer Oliver W. , Belizario Vicente Y. , Storey Helen L. , de Hostos Eugenio L. , de los Santos Tala
Published: September 2021

Background

Soil-transmitted helminths (STHs) are parasitic nematodes that inhabit the human intestine. They affect more than 1.5 billion people worldwide, causing physical and cognitive impairment in children. The global strategy to control STH infection includes periodic mass drug administration (MDA) based on the results of diagnostic testing among populations at risk, but the current microscopy method for detecting infection has diminished sensitivity as the intensity of infection decreases. Thus, improved diagnostic tools are needed to support decision-making for STH control programs.

Methodology

We developed a nucleic acid amplification test based on recombinase polymerase amplification (RPA) technology to detect STH in stool. We designed primers and probes for each of the four STH species, optimized the assay, and then verified its performance using clinical stool samples.

Principal findings

Each RPA assay was as sensitive as a real-time polymerase chain reaction (PCR) assay in detecting copies of cloned target DNA sequences. The RPA assay amplified the target in DNA extracted from human stool samples that were positive for STH based on the Kato-Katz method, with no cross-reactivity of the non-target genomic DNA. When tested with clinical stool samples from patients with infections of light, moderate, and heavy intensity, the RPA assays demonstrated performance comparable to that of real-time PCR, with better results than Kato-Katz. This new rapid, sensitive and field-deployable method for detecting STH infections can help STH control programs achieve their goals.

Conclusions

Semi-quantitation of target by RPA assay is possible and is comparable to real-time PCR. With proper instrumentation, RPA assays can provide robust, semi-quantification of STH DNA targets as an alternative field-deployable indicator to counts of helminth eggs for assessing infection intensity.
Health belief model factors as predictors of parental misclassification of the weight of the preschool child
Authors: Woods Tanna , Nies Mary A.
Published: September 2021

Background

Parental misperception and underestimation of their child’s weight are documented in studies. Demographic factors like age and gender have been linked to misclassification. However, modifiable factors that could potentially frame future intervention and prevention strategies have not been explored. This study aimed to assess factors that could predict parental misclassification of their preschool child’s weight.

Methods

This was a cross-sectional study with 198 parents and their 2- to 5-year-old children who attended standalone preschools or childcare centers with preschools. Parents completed a questionnaire that asked about demographic features, personal and family health, and the assessment of their child’s weight using the three most frequently utilized measures. Logistic regression was conducted to assess the association between parental factors and child weight classification status. Instruments included the Parental Self-Efficacy for Promoting Healthy Physical Activity and Dietary Behaviors in Children Scale (PSEPAD), the Obesity Risk Scale (ORK-10), and the Adolescent Obesity Risk Scale (AORK). Analyses included frequencies, chi-square tests, Kappa coefficients, and logistic regressions.

Results

Parents were least accurate (35.9%) identifying child weight when selecting a picture (κ = -.028, p = .42). The pictorial and Likert method (κ = -.032, p = .37) showed parental agreement with child weight was not significantly better than chance. Statistically, a significant agreement was found in the weight-reporting method (κ = .21). Two of the three HBM-related measures were significantly related to accurate classification. Logistic regression showed child sex, PSEPAD scores, and ORK-10 scores were statistically significant predictors in the Likert method. The model had no statistical significance for the pictorial or weight-reporting method.

Conclusion

Results indicate parents support intervening if aware of child weight problems. However, parents do not accurately recognize healthy versus unhealthy weights and report that health providers are not informing them of weight deviations. Further, important relationships between the HBM variables were identified. Results show barriers (self-efficacy) mediate the impact of perceived severity (knowledge) regarding the parental ability to assess child weight accurately. These relationships and incorporation of the HBM principles of barriers and severity into prevention/intervention strategies need further exploration.
Bacterial diversity dynamics in microbial consortia selected for lignin utilization
Authors: Mendes Isis Viana , Garcia Mariana Botelho , Bitencourt Ana Carolina Araújo , Santana Renata Henrique , Lins Philippe de Castro , Silveira Rafaella , Simmons Blake A. , Gladden John M. , Kruger Ricardo Henrique , Quirino Betania Ferraz
Published: September 2021

Lignin is nature’s largest source of phenolic compounds. Its recalcitrance to enzymatic conversion is still a limiting step to increase the value of lignin. Although bacteria are able to degrade lignin in nature, most studies have focused on lignin degradation by fungi. To understand which bacteria are able to use lignin as the sole carbon source, natural selection over time was used to obtain enriched microbial consortia over a 12-week period. The source of microorganisms to establish these microbial consortia were commercial and backyard compost soils. Cultivation occurred at two different temperatures, 30°C and 37°C, in defined culture media containing either Kraft lignin or alkaline-extracted lignin as carbon source. iTag DNA sequencing of bacterial 16S rDNA gene was performed for each of the consortia at six timepoints (passages). The initial bacterial richness and diversity of backyard compost soil consortia was greater than that of commercial soil consortia, and both parameters decreased after the enrichment protocol, corroborating that selection was occurring. Bacterial consortia composition tended to stabilize from the fourth passage on. After the enrichment protocol, Firmicutes phylum bacteria were predominant when lignin extracted by alkaline method was used as a carbon source, whereas Proteobacteria were predominant when Kraft lignin was used. Bray-Curtis dissimilarity calculations at genus level, visualized using NMDS plots, showed that the type of lignin used as a carbon source contributed more to differentiate the bacterial consortia than the variable temperature. The main known bacterial genera selected to use lignin as a carbon source were Altererythrobacter, Aminobacter, Bacillus, Burkholderia, Lysinibacillus, Microvirga, Mycobacterium, Ochrobactrum, Paenibacillus, Pseudomonas, Pseudoxanthomonas, Rhizobiales and Sphingobium. These selected bacterial genera can be of particular interest for studying lignin degradation and utilization, as well as for lignin-related biotechnology applications.
Clinical impact of serum exosomal microRNA in liver fibrosis
Authors: Chang Young , Han Jae-A. , Kang Suk Min , Jeong Soung Won , Ryu Tom , Park Han Seul , Yoo Jeong-Ju , Lee Sae Hwan , Kim Sang Gyune , Kim Young Seok , Kim Hong Soo , Jin So Young , Ryu Seongho , Jang Jae Young
Published: September 2021

Background/aim

We investigated alterations in the expression of serum exosomal miRNAs with the progression of liver fibrosis and evaluated their clinical applicability as biomarkers.

Methods

This study prospectively enrolled 71 patients who underwent liver biopsy at an academic hospital in Korea. Exosomes were extracted from serum samples, followed by next-generation sequencing (NGS) of miRNAs and targeted real-time quantitative polymerase chain reaction. A model was derived to discriminate advanced fibrosis based on miRNA levels and the performance of this model was evaluated. Validation of the effect of miRNA on liver fibrosis in vitro was followed.

Results

NGS data revealed that exosomal miR-660-5p, miR-125a-5p, and miR-122 expression were changed significantly with the progression of liver fibrosis, of which miR-122 exhibited high read counts enough to be used as a biomarker. The level of exosomal miR-122 decreased as the pathologic fibrosis grade progressed and patients with biopsy-proven advanced fibrosis had significantly lower levels of exosomal miR-122 (P < 0.001) than those without advanced fibrosis. Exosomal miR-122 exhibited a fair performance in discriminating advanced fibrosis especially in combination with fibrosis-4 score and transient elastography. In a subgroup of patients with a non-viral etiology of liver disease, the performance of exosomal miR-122 as a biomarker was greatly improved. Inhibition of miR-122 expression increased the proliferation of the human hepatic stellate cell line, LX-2, and upregulated the expression of various fibrosis related proteins.

Conclusion

Exosomal miR-122 may serve as a useful non-invasive biomarker for liver fibrosis, especially in patients with non-viral etiologies of chronic liver disease.
Analysis of factors influencing levee safety using the DEMATEL method
Authors: Mirosław-Świątek Dorota , Popielski Paweł , Śliwiński Piotr , Cwalina Tomasz , Skutnik Zdzisław
Published: September 2021

River embankments are the basic and the oldest measures of protecting areas potentially subjected to flooding, and at the same time pose a serious threat to their environment in the event of damage or failure. The technical condition of the levees and its regular evaluation is a key element of their safety. A general assessment of the technical condition of a levee is the result of many interacting factors and parameters that depend on each other to a varying degree. Therefore, it is necessary to consider the cause-and-effect links between the interrelationships of numerous parameters and sensors of significant impact. In this article the decision-making trial and evaluation laboratory (DEMATEL) method was applied to develop a cause-and-effect model for factors impacting the condition and safety of levees. Effective factors impacting the technical condition of a levee were identified; relationships between these factors were determined; a cause-and-effect model was developed based on identified factors; factors were categorized based on the dependence scale and influential indicators of each factors used in the DEMATEL method. The obtained results demonstrate that three following factors: hydrological factor, type and condition of soils in levee body and condition of levee areas (inter-levee and landside) play the most important role for levee safety. The results of this study can support traditional assessments of hydrotechnical structure or assist entities managing levees.
The Kanyakla study: Randomized controlled trial of a microclinic social network intervention for promoting engagement and retention in HIV care in rural western Kenya
Authors: Hickey Matthew D. , Ouma Gor B. , Mattah Brian , Pederson Ben , DesLauriers Nicholas R. , Mohamed Pamela , Obanda Joyce , Odhiambo Abdi , Njoroge Betty , Otieno Linda , Zoughbie Daniel E. , Ding Eric L. , Fiorella Kathryn J. , Bukusi Elizabeth A. , Cohen Craig R. , Geng Elvin H. , Salmen Charles R.
Published: September 2021

Background

Existing social relationships are a potential source of “social capital” that can enhance support for sustained retention in HIV care. A previous pilot study of a social network-based ‘microclinic’ intervention, including group health education and facilitated HIV status disclosure, reduced disengagement from HIV care. We conducted a pragmatic randomized trial to evaluate microclinic effectiveness.

Methods

In nine rural health facilities in western Kenya, we randomized HIV-positive adults with a recent missed clinic visit to either participation in a microclinic or usual care (NCT02474992). We collected visit data at all clinics where participants accessed care and evaluated intervention effect on disengagement from care (≥90-day absence from care after a missed visit) and the proportion of time patients were adherent to clinic visits (‘time-in-care’). We also evaluated changes in social support, HIV status disclosure, and HIV-associated stigma.

Results

Of 350 eligible patients, 304 (87%) enrolled, with 154 randomized to intervention and 150 to control. Over one year of follow-up, disengagement from care was similar in intervention and control (18% vs 17%, hazard ratio 1.03, 95% CI 0.61–1.75), as was time-in-care (risk difference -2.8%, 95% CI -10.0% to +4.5%). The intervention improved social support for attending clinic appointments (+0.4 units on 5-point scale, 95% CI 0.08–0.63), HIV status disclosure to close social supports (+0.3 persons, 95% CI 0.2–0.5), and reduced stigma (-0.3 units on 5-point scale, 95% CI -0.40 to -0.17).

Conclusions

The data from our pragmatic randomized trial in rural western Kenya are compatible with the null hypothesis of no difference in HIV care engagement between those who participated in a microclinic intervention and those who did not, despite improvements in proposed intervention mechanisms of action. However, some benefit or harm cannot be ruled out because the confidence intervals were wide. Results differ from a prior quasi-experimental pilot study, highlighting important implementation considerations when evaluating complex social interventions for HIV care.

Trial registration

Clinical trial number: NCT02474992.
Temporal binding window and sense of agency are related processes modifiable via occipital tACS
Authors: Venskus Agnese , Ferri Francesca , Migliorati Daniele , Spadone Sara , Costantini Marcello , Hughes Gethin
Published: September 2021

The temporal binding window refers to the time frame within which temporal grouping of sensory information takes place. Sense of agency is the feeling of being in control of one’s actions, and their associated outcomes. While previous research has shown that temporal cues and multisensory integration play a role in sense of agency, no studies have directly assessed whether individual differences in the temporal binding window and sense of agency are associated. In all three experiments, to assess sense of agency, participants pressed a button triggering, after a varying delay, the appearance of the circle, and reported their sense of agency over the effect. To assess the temporal binding window a simultaneity judgment task (Experiment 1) and a double-flash illusion task (Experiment 2 and 3) was also performed. As expected, the temporal binding window correlated with the sense of agency window. In Experiment 3, these processes were modulated by applying occipital tACS at either 14Hz or 8Hz. We found 14Hz tACS stimulation was associated with narrower temporal biding window and sense of agency window. Our results suggest the temporal binding window and the time window of sense of agency are related. They also point towards a possible underlying neural mechanism (alpha peak frequency) for this association.
Relation classification via BERT with piecewise convolution and focal loss
Authors: Liu Jianyi , Duan Xi , Zhang Ru , Sun Youqiang , Guan Lei , Lin Bingjie
Published: September 2021

Recent relation extraction models’ architecture are evolved from the shallow neural networks to natural language model, such as convolutional neural networks or recurrent neural networks to Bert. However, these methods did not consider the semantic information in the sequence or the distance dependence problem, the internal semantic information may contain the useful knowledge which can help relation classification. Focus on these problems, this paper proposed a BERT-based relation classification method. Compare with the existing Bert-based architecture, the proposed model can obtain the internal semantic information between entity pair and solve the distance semantic dependence better. The pre-trained BERT model after fine tuning is used in this paper to abstract the semantic representation of sequence, then adopt the piecewise convolution to obtain semantic information which influence the extraction results. Compare with the existing methods, the proposed method can achieve a better accuracy on relational extraction task because of the internal semantic information extracted in the sequence. While, the generalization ability is still a problem that cannot be ignored, and the numbers of the relationships are difference between different categories. In this paper, the focal loss function is adopted to solve this problem by assigning a heavy weight to less number or hard classify categories. Finally, comparing with the existing methods, the F1 metric of the proposed method can reach a superior result 89.95% on the SemEval-2010 Task 8 dataset.
Defective expansion and function of memory like natural killer cells in HIV+ individuals with latent tuberculosis infection
Authors: Devalraju Kamakshi Prudhula , Neela Venkata Sanjeev Kumar , Krovvidi Siva Sai , Vankayalapati Ramakrishna , Valluri Vijaya Lakshmi
Published: September 2021

Purpose

Tuberculosis (TB) is the leading cause of infectious disease related mortality, and only 10% of the infected individuals develop active disease. The likelihood of progression of latent tuberculosis infection (LTBI) to active TB disease is high in HIV infected individuals. Identification of HIV+ individuals at risk would allow treating targeted population, facilitating completion of therapy for LTBI and prevention of TB development. NK cells have an important role in T cell independent immunity against TB, but the exact role of NK cell subsets in LTBI and HIV is not well characterized.

Methods

In this study, we compared the expansion and function of memory like NK cells from HIV-LTBI+ individuals and treatment naïve HIV+LTBI+ patients in response to Mtb antigens ESAT-6 and CFP-10.

Results

In freshly isolated PBMCs, percentages of CD3-CD56+NK cells were similar in HIV+LTBI+ patients and healthy HIV-LTBI+ individuals. However, percentages of CD3-CD56+CD16+NK cells were higher in healthy HIV-LTBI+ individuals compared to HIV+LTBI+ patients. HIV infection also inhibited the expansion of memory like NK cells, production of IL-32α, IL-15 and IFN-γ in response to Mtb antigens in LTBI+ individuals.

Conclusion

We studied phenotypic, functional subsets and activation of memory like-NK cells during HIV infection and LTBI. We observed that HIV+LTBI+ patients demonstrated suboptimal NK cell and monocyte interactions in response to Mtb, leading to reduced IL-15, IFN-γ and granzyme B and increased CCL5 production. Our study highlights the effect of HIV and LTBI on modulation of NK cell activity to understand their role in development of interventions to prevent progression to TB in high risk individuals.
Experiences of transgender and non-binary youth accessing gender-affirming care: A systematic review and meta-ethnography
Authors: Kearns Seán , Kroll Thilo , O‘Shea Donal , Neff Karl
Published: September 2021

Objective

Transgender and non-binary individuals frequently engage with healthcare services to obtain gender-affirming care. Little data exist on the experiences of young people accessing gender care. This systematic review and meta-ethnography aimed to identify and synthesise data on youths’ experiences accessing gender-affirming healthcare.

Method

A systematic review and meta-ethnography focusing on qualitative research on the experiences of transgender and non-binary youth accessing gender care was completed between April-December 2020. The following databases were used: PsychINFO, MEDLINE, EMBASE, and CINAHL. The protocol was registered on PROSPERO, international prospective register of Systematic Reviews (CRD42020139908).

Results

Ten studies were included in the final review. The sample included participants with diverse gender identities and included the perspective of parents/caregivers. Five dimensions (third-order constructs) were identified and contextualized into the following themes: 1.) Disclosure of gender identity. 2.) The pursuit of care. 3.) The cost of care. 4.) Complex family/caregiver dynamics. 5.) Patient-provider relationships. Each dimension details a complicated set of factors that can impact healthcare navigation and are explained through a new conceptual model titled “The Rainbow Brick Road”.

Conclusion

This synthesis expands understanding into the experience of transgender and non-binary youth accessing gender-affirming healthcare. Ryvicker’s behavioural-ecological model of healthcare navigation is discussed in relation to the findings and compared to the authors’ conceptual model. This detailed analysis reveals unique insights on healthcare navigation challenges and the traits, resources, and infrastructure needed to overcome these. Importantly, this paper reveals the critical need for more research with non-binary youth and research which includes the population in the design.
Comparative analysis of the ex vivo IFN-gamma responses to CD8+ T cell epitopes within allelic forms of PfAMA1 in subjects with natural exposure to malaria
Authors: Nlinwe Omarine N. , Ofori Ebenezer A. , Akyea-Mensah Kwadwo , Kyei-Baafour Eric , Ganeshan Harini , Belmonte Maria , Peters Bjoern , Villasante Eileen , Sedegah Martha , Kusi Kwadwo Asamoah
Published: September 2021

Antigen polymorphisms in essential malarial antigens are a key challenge to the design and development of broadly effective malaria vaccines. The effect of polymorphisms on antibody responses is fairly well studied while much fewer studies have assessed this for T cell responses. This study investigated the effect of allelic polymorphisms in the malarial antigen apical membrane antigen 1 (AMA1) onex vivoT cell-specific IFN-γ responses in subjects with lifelong exposure to malaria. Human leukocyte antigen (HLA) class I-restricted peptides from the 3D7 clone AMA1 were bioinformatically predicted and those with variant amino acid positions used to select corresponding allelic sequences from the 7G8, FVO, FC27 and tm284 parasite strains. A total of 91 AMA1 9-10mer peptides from the five parasite strains were identified, synthesized, grouped into 42 allele sets and used to stimulate PBMCs from seven HLA class 1-typed subjects in IFN-γ ELISpot assays. PBMCs from four of the seven subjects (57%) made positive responses to 18 peptides within 12 allele sets. Fifty percent of the 18 positive peptides were from the 3D7 parasite variant. Amino acid substitutions that were associated with IFN-γ response abrogation were more frequently found at positions 1 and 6 of the tested peptides, but substitutions did not show a clear pattern of association with response abrogation. Thus, while we show some evidence of polymorphisms affecting T cell response induction, other factors including TCR recognition of HLA-peptide complexes may also be at play.
Assessing feasibility and maternal acceptability of a biomechanically-optimized supine birth position: A pilot study
Authors: Bouille Lisa , Sichitiu Joanna , Favre Julien , Desseauve David
Published: September 2021

Background

In order to manage a protracted second stage of labor, “eminence-based” birth positions have been suggested by some healthcare professionals. Recent biomechanical studies have promoted the use of an optimized supine birthing position in this setting. However, uncertainty exists regarding the feasibility of this posture, and its acceptability by women. This pilot study primarily aimed to assess these characteristics.

Objective and methods

In this monocentric prospective study, 20 women with a protracted second stage of labor were asked to maintain a biomechanically-optimized position for at least 20 minutes at full dilatation. This posture is similar to the McRoberts’ maneuver. Maintaining the position for 20 minutes or more was considered clinically relevant and indicative of feasibility and acceptability. Satisfaction with the position was assessed using a Visual Analogue Scale (VAS). A sub-group analysis was performed to assess eventual differences between more and less satisfied patients, according to the median of patients’ satisfaction scores.

Results

Seventeen patients (85%) maintained the optimized position for at least 20 minutes. The median satisfaction score of these participants was 8 (interquartile range: 1) out of 10. No significant differences were found between the two sub-groups (satisfaction score <8 vs satisfaction score ≥8) regarding general and obstetric characteristics, as well as obstetrical and fetal outcomes.

Conclusion

The optimized position is acceptable and feasible for women experiencing a protracted second stage of labor. Further clinical studies are needed to assess the efficiency of such positions when women undergo an obstructed labor.
Size-specific dose estimates of adult, chest computed tomography examinations: Comparison of Chinese and updated 2017 American College of Radiology diagnostic reference levels based on the water-equivalent diameter
Authors: Hu Xiaoyan , Gou Jie , Lin Wei , Zou Chunhua , Li Wenbo
Published: September 2021

Rationale and objectives

This study aimed to compare the volume computed tomography dose index (CTDIvol), dose length product (DLP), and size-specific dose estimate (SSDE), with the China and updated 2017 American College of Radiology (ACR) diagnostic reference levels (DRLs) in chest CT examinations of adults based on the water-equivalent diameter (Dw).

Materials and methods

All chest CT examinations conducted without contrast administration from January 2020 to July 2020 were retrospectively included in this study. The Dw and SSDE of all examinations were calculated automatically by “teamplay”. The CTDIvol and DLP were displayed on the DICOM-structured dose report in the console based on a 32cm phantom.The differences in patient CTDIvol, DLP, and SSDE values between groups were examined by the one-way ANOVA. The differences in patient CTDIvol, DLP, and SSDE values between the updated 2017 ACR and the China DRLs were examined with one sample t-tests.

Results

In total 14666 chest examinations were conducted in our study. Patients were divided into four groups based on Dw:270 (1.84%) in 15–20 cm group, 10287 (70.14%) in the 21–25 cm group, 4097 (27.94%) in the 26–30 cm group, and 12 (0.08%) patients had sizes larger than 30 cm. CTDIvol, DLP, and SSDE increased as a function of Dw (p<0.05). CTDIvol was smaller than SSDE among groups (p<0.05). The mean CTDIvol and DLP values were lower than the 25th, 50th, and 75thpercentile of the China DRLs (p <0.05). The CTDIvol, DLP, and SSDE were lower than the 50thand 75thpercentiles of the updated 2017 ACR DRLs (p <0.05) among groups.

Conclusions

SSDE takes into account the influence of the scanning parameters, patient size, and X-ray attenuation on the radiation dose, which can give a more realistic estimate of radiation exposure dose for patients undergoing CT examinations. Establishing hospital’s own DRL according to CTDIvol and SSDE is very important even though the radiation dose is lower than the national DRLs.
Psychological distress, fear and coping among Malaysians during the COVID-19 pandemic
Authors: Bahar Moni Ahmed Suparno , Abdullah Shalimar , Bin Abdullah Mohammad Farris Iman Leong , Kabir Mohammed Shahjahan , Alif Sheikh M. , Sultana Farhana , Salehin Masudus , Islam Sheikh Mohammed Shariful , Cross Wendy , Rahman Muhammad Aziz
Published: September 2021

Introduction

The COVID-19 pandemic has enormously affected the psychological well-being, social and working life of millions of people across the world. This study aimed to investigate the psychological distress, fear and coping strategies as a result of the COVID-19 pandemic and its associated factors among Malaysian residents.

Methods

Participants were invited to an online cross-sectional survey from Aug-Sep 2020. The study assessed psychological distress using the Kessler Psychological Distress Scale, level of fear using the Fear of COVID-19 Scale, and coping strategies using the Brief Resilient Coping Scale. Univariate and multivariate logistic regression analyses were conducted to adjust for potential confounders.

Results

The mean age (±SD) of the participants (N = 720) was 31.7 (±11.5) years, and most of them were females (67.1%). Half of the participants had an income source, while 216 (30%) identified themselves as frontline health or essential service workers. People whose financial situation was impacted due to COVID-19 (AOR 2.16, 95% CIs 1.54–3.03), people who drank alcohol in the last four weeks (3.43, 1.45–8.10), people who were a patient (2.02, 1.39–2.93), and had higher levels of fear of COVID-19 (2.55, 1.70–3.80) were more likely to have higher levels of psychological distress. Participants who self-isolated due to exposure to COVID-19 (3.12, 1.04–9.32) and who had moderate to very high levels of psychological distress (2.56, 1.71–3.83) had higher levels of fear. Participants who provided care to a family member/patient with a suspected case of COVID-19 were more likely to be moderately to highly resilient compared to those who did not.

Conclusion

Vulnerable groups of individuals such as patients and those impacted financially during COVID-19 should be supported for their mental wellbeing. Behavioural interventions should be targeted to reduce the impact of alcohol drinking during such crisis period.