bluuebunny/crossref_metadata_2025 huggingface dataset:
Hybrid non-sequential modeling of an image mapping spectrometer
Authors: Liu Anqi , Yuan Yan , Su Lijuan , Meng Xiangxiang , Shao Haotian , Jiang Yi
Published: May 2022

An image mapping spectrometer (IMS) is a kind of snapshot imaging spectrometer characterized by containing several array components including the image mapper, prism array, and reimaging lens array. We propose a hybrid non-sequential modeling method of IMS and present the complete optical model of the system built in Zemax. This method utilizes the spatial periodicity of the array components and requires only a small number of input parameters. Moreover, we design a collimating lens of a large relative aperture, sufficient working distance, and low aberration to meet the requirements of an IMS with good optical performance and compact volume. The designed lens is quantitatively evaluated in the entire IMS model, and the results demonstrate that the lens has excellent optical performance. The evaluation on the collimating lens also demonstrates the capability of the proposed modeling method in the design and optimization of systems such as the IMS that contain multiple array components. The designed collimating lens is manufactured and assembled in the experimental setup of the IMS. The proposed modeling method is verified by experimental results.
Recent advances in light sources on silicon
Authors: Han Yu , Park Hyundai , Bowers John , Lau Kei May
Published: May 2022

Realizing efficient on-chip light sources has long been the
“holy-grail” for Si-photonics research. Several
important breakthroughs were made in this field in the past few years.
In this article, we review the most recent advances in light sources
integrated onto mainstream Si platforms and discuss four different
integration technologies: Group IV light sources on Si, heterogeneous
integration of III–V light sources on Si, blanket heteroepitaxy
of III–V light sources on Si, and selective heteroepitaxy of
III–V light sources on Si. We start with briefly introducing
the basic concepts of each technology and then focus on the recent
progress via presenting the most representative device demonstrations.
Finally, we discuss the research challenges and opportunities
associated with each technology.
Surface waves in a linearly graded-index and an intensity-dependent index layered structure
Authors: Savotchenko S. E.
Published: May 2022

A new type surface wave is found that propagates in a linearly graded-index and an intensity-dependent index layered structure characterized by an abrupt change in the dielectric constant. The main surface wave characteristics are calculated analytically. The optical domain, the thickness of which increases with an increasing effective refractive index and decreases with an increasing characteristic distance, is formed. It is discovered that the characteristic distance of the graded-index medium and effective refractive index can control wave energy redistribution between the semiconductor layers.
Unidirectional amplification in optomechanical system coupling with a structured bath
Authors: Peng Rui , Zhang Wen-Zhao , Chao Shilei , Zhao Chengsong , Yang Zhen , Yang Junya , Zhou Ling
Published: May 2022

Nonreciprocity plays an indispensable role in quantum information transmission. We theoretically study the unidirectional amplification in the non-Markovian regime, in which a nanosphere surrounded by a structured bath is trapped in a single (dual)-mode cavity. The global mechanical response function of the nanosphere is markedly altered by the non-Markovian structured bath through shifting the effective frequency and magnifying the response function. Consequently, when there is a small difference in the transmission rate within the regime of Markovian, the unidirectional amplification is achieved in the super-Ohmic spectral environment. In the double-optomechanical coupling system, the phase difference between two optomechanical couplings can reverse the transmission direction. Meanwhile, the non-Markovian bath still can amplify the signal because of the XX-type coupling between nanosphere and its bath.
BM3D-based denoising method for color polarization filter array
Authors: Liang Jian-An , Guo Ya-fei , Liu Bin
Published: May 2022

Color split-focal plane polarization imaging systems are composed of image sensors with a color polarization filter array (CPFA). The noise generated during image acquisition leads to incorrect estimation of the color polarization information. Therefore, it is necessary to denoise CPFA image data. In this study, we propose a CPFA block-matching and 3D filtering (CPFA-BM3D) algorithm for CPFA image data. The algorithm makes full use of the correlation between different polarization channels and different color channels, restricts the grouping of similar 2D image blocks to form 3D blocks, and attenuates Gaussian noise in the transform domain. We evaluate the denoising performance of the proposed algorithm using simulated and real CPFA images. Experimental results show that the proposed method significantly suppresses noise while preserving the image details and polarization information. Its peak signal-to-noise ratio (PSNR) and structural similarity (SSIM) indicators are superior to those of the other existing methods. The mean values of the PSNR and SSIM of the degree of linear polarization (DoLP) color images calculated through CPFA image interpolation can be increased to 200% and 400%, respectively, by denoising with the proposed method.
Non-uniformity correction of wide field of view imaging system
Authors: Ji Yiqun , Zeng Chenxin , Tan Fenli , Feng Anwei , Han Jizhou
Published: May 2022

Requirements for wide field of view (FOV) imaging system reflect the need for both uniform illumination as well as excellent image quality across the entire FOV. As the monocentric lens combined with a parallel array of relay imagers achieves a wide-FOV while maintaining a high resolution, we studied the monocentric cascade imaging system (MCIS). However, the imaging experiment of the prototype shows two issues, including vignetting and non-uniform image quality over the full FOV. They affect the image stitching which is necessary for wide-FOV image acquisition. This paper studies how the position of the aperture stop affects the vignetting and the local aberrations in MCIS. Moving laws of the aperture stop and its relationship with the local aberrations are presented. Moreover, aspheric surfaces on proper surfaces are introduced and studied to balance the local aberrations. Accordingly, an MCIS with uniform illumination and good image quality is presented. The MCIS achieves a wide-FOV of 116.4° and an instantaneous FOV of 0.0021°. It keeps a relative illumination exceeding 97% during the full FOV. The modulation transfer function (MTF) is over 0.285 at the Nyquist frequency of 270 lp/mm. This paper provides a profound theorical reference for further applications and developments of MCIS.
Dual-linear chirp microwave signal generation by using single-beam injection to a DFB semiconductor laser and optical heterodyne technique
Authors: Jin YanHong , Lin XiaoDong , Wu ZhengMao , Yue DianZou , Zhang FengLing , Zhang Li , Jiang ZaiFu , Xia GuangQiong
Published: May 2022

Based on a single-beam injection distributed feedback semiconductor laser (DFB-SL) combining with optical heterodyne, a photonic scheme for generating dual-linear chirp microwave (dual-LCM) signal with identical or complementary chirp is proposed and experimentally demonstrated. For such a scheme, a continuous-wave (CW) light with a frequency of finj is split into two parts. One part is passing through a Mach-Zehnder modulator (MZM) driven by a modified sawtooth signal, and then its intensity varies with time as a sawtooth wave. Such a light is injected to a DFB-SL for generating a single linearly chirped microwave (single-LCM) signal. The other part of the CW light with frequency of finj is sent to a phase modulator (PM) driven by a sinusoidal signal, and one of higher-order sidebands is selected by a tunable optical filter and taken as the referenced light. Through heterodyning the referenced light with the single-LCM signal, a dual-LCM signal with identical (or complementary) chirp can be obtained. The experimental results demonstrate that, by adjusting the injection parameters and the frequency of the sinusoidal signal loaded on the PM, the central frequency of the generated dual-LCM signal can be widely tuned. For the period of the sawtooth signal at 10 µs, the bandwidth for each frequency band included in the generated dual-LCM signal is 19.36 GHz under identical chirp and 16.98 GHz under complementary chirp, respectively. Correspondingly, the time bandwidth product (TBWP) for each frequency band can reach 1.936 × 105 under identical chirp and 1.698 × 105 under complementary chirp, respectively.
Using the dynamic forward scattering signal for optical coherence tomography based blood flow quantification
Authors: Nam Ahhyun Stephanie , Braaf Boy , Vakoc Benjamin J.
Published: May 2022

To our knowledge, all existing optical coherence tomography approaches for quantifying blood flow, whether Doppler-based or decorrelation-based, analyze light that is back-scattered by moving red blood cells (RBCs). This work investigates the potential advantages of basing these measurements on light that is forward-scattered by RBCs, i.e., by looking at the signals back-scattered from below the vessel. We show experimentally that flowmetry based on forward-scattering is insensitive to vessel orientation for vessels that are approximately orthogonal to the imaging beam. We further provide proof-of-principle demonstrations of dynamic forward-scattering (DFS) flowmetry in human retinal and choroidal vessels.
Observation of the Wannier–Stark ladder in plasmonic waveguide arrays
Authors: Wetter Helene , Fedorova Zlata , Linden Stefan
Published: May 2022

Evanescently coupled waveguides are a powerful platform to study and visualize the wave dynamics in tight-binding systems. Here, we investigate the propagation of surface plasmon polaritons in arrays of dielectric loaded surface plasmon polariton waveguides with a propagation constant gradient acting as an effective external potential. Using leakage radiation microscopy, we observe in real-space for single site excitation a periodic breathing of the wave packet and an oscillatory motion in the case of Gaussian excitation of multiple waveguides. The corresponding momentum­resolved spectra are composed of sets of equally spaced modes. We interpret these observations as the plasmonic analogs of Bloch oscillations and the Wannier–Stark ladder, respectively.
Sub-40 fs optical parametric oscillator beyond the gain bandwidth limit
Authors: Alabbadi Abdullah , Steinle Tobias , Giessen Harald
Published: May 2022

We report a compact and passively stable optical parametric oscillator for direct generation of sub-40 fs pulses, five times shorter than the 200 fs pump oscillator. By employing an intracavity all normal dispersion feedback fiber, we achieved low-noise and coherent broadening beyond the parametric gain bandwidth limitation. We demonstrate spectral coverage from 1.1 to 2.0 µm with excellent passive power and spectral stability below 0.1% rms and a footprint smaller than 14 × 14 cm2.
Performance-gated deliberation: A context-adapted strategy in which urgency is opportunity cost
Authors: Puelma Touzel Maximilian , Cisek Paul , Lajoie Guillaume
Published: May 2022

Finding the right amount of deliberation, between insufficient and excessive, is a hard decision making problem that depends on the value we place on our time. Average-reward, putatively encoded by tonic dopamine, serves in existing reinforcement learning theory as the opportunity cost of time, including deliberation time. Importantly, this cost can itself vary with the environmental context and is not trivial to estimate. Here, we propose how the opportunity cost of deliberation can be estimated adaptively on multiple timescales to account for non-stationary contextual factors. We use it in a simple decision-making heuristic based on average-reward reinforcement learning (AR-RL) that we call Performance-Gated Deliberation (PGD). We propose PGD as a strategy used by animals wherein deliberation cost is implemented directly as urgency, a previously characterized neural signal effectively controlling the speed of the decision-making process. We show PGD outperforms AR-RL solutions in explaining behaviour and urgency of non-human primates in a context-varying random walk prediction task and is consistent with relative performance and urgency in a context-varying random dot motion task. We make readily testable predictions for both neural activity and behaviour.
Sequence dependence of transient Hoogsteen base pairing in DNA
Authors: Pérez de Alba Ortíz Alberto , Vreede Jocelyne , Ensing Bernd
Published: May 2022

Hoogsteen (HG) base pairing is characterized by a 180° rotation of the purine base with respect to the Watson-Crick-Franklin (WCF) motif. Recently, it has been found that both conformations coexist in a dynamical equilibrium and that several biological functions require HG pairs. This relevance has motivated experimental and computational investigations of the base-pairing transition. However, a systematic simulation of sequence variations has remained out of reach. Here, we employ advanced path-based methods to perform unprecedented free-energy calculations. Our methodology enables us to study the different mechanisms of purine rotation, either remaining inside or after flipping outside of the double helix. We study seven different sequences, which are neighbor variations of a well-studied A⋅T pair in A6-DNA. We observe the known effect of A⋅T steps favoring HG stability, and find evidence of triple-hydrogen-bonded neighbors hindering the inside transition. More importantly, we identify a dominant factor: the direction of the A rotation, with the 6-ring pointing either towards the longer or shorter segment of the chain, respectively relating to a lower or higher barrier. This highlights the role of DNA’s relative flexibility as a modulator of the WCF/HG dynamic equilibrium. Additionally, we provide a robust methodology for future HG proclivity studies.
A literature review on the analysis of symptom-based clinical pathways: Time for a different approach?
Authors: Gunatilleke Nammunikankanange Janak , Fleuriot Jacques , Anand Atul
Published: May 2022

Breathlessness is a common clinical presentation, accounting for a quarter of all emergency hospital attendances. As a complex undifferentiated symptom, it may be caused by dysfunction in multiple body systems. Electronic health records are rich with activity data to inform clinical pathways from undifferentiated breathlessness to specific disease diagnoses. These data may be amenable to process mining, a computational technique that uses event logs to identify common patterns of activity. We reviewed use of process mining and related techniques to understand clinical pathways for patients with breathlessness. We searched the literature from two perspectives: studies of clinical pathways for breathlessness as a symptom, and those focussed on pathways for respiratory and cardiovascular diseases that are commonly associated with breathlessness. The primary search included PubMed, IEEE Xplore and ACM Digital Library. We included studies if breathlessness or a relevant disease was present in combination with a process mining concept. We excluded non-English publications, and those focussed on biomarkers, investigations, prognosis, or disease progression rather than symptoms. Eligible articles were screened before full-text review. Of 1,400 identified studies, 1,332 studies were excluded through screening and removal of duplicates. Following full-text review of 68 studies, 13 were included in qualitative synthesis, of which two (15%) were symptom and 11 (85%) disease focused. While studies reported highly varied methodologies, only one included true process mining, using multiple techniques to explore Emergency Department clinical pathways. Most included studies trained and internally validated within single-centre datasets, limiting evidence for wider generalisability. Our review has highlighted a lack of clinical pathway analyses for breathlessness as a symptom, compared to disease-focussed approaches. Process mining has potential application in this area, but has been under-utilised in part due to data interoperability challenges. There is an unmet research need for larger, prospective multicentre studies of patient pathways following presentation with undifferentiated breathlessness.
Prevalence and factors associated with hyperglycemia in a rural population of Tanvè and Dékanmey in Benin in 2019
Authors: Amegan Nicolas Hamondji , Amidou Ariyoh Salmane , Houehanou Corine Yessito , Robin Helene , Gbaguidi Gwladys Nadia , Fassinou Corine Agathe Lucresse , Amoussou-Guenou Kuassi Daniel , Preux Pierre-Marie , Lacroix Philippe , Houinato Stephan Dismand ,   on behalf of TAHES group
Published: May 2022

Background

Hyperglycemia leads to serious damage to the body, especially the blood vessels and nerves. This study aimed to determine the prevalence and factors associated with hyperglycemia in a rural population of Tanvè and Dékanmey in Benin in 2019.

Materials and methods

This was a cross-sectional, descriptive and analytical study, nested in the Tanvè Health Study (TAHES) cohort. It covered all residents of the villages of Tanvè and Dékanmey, aged 25 years and above, and having given their written consent. Data were collected in the households during the fourth annual monitoring visit in 2019 using the WHO STEPS Wise approach. Hyperglycemia was defined as a fasting capillary blood glucose value ≥ 110 mg/dL. Data were analyzed with R Studio software version 3.5.1.

Results

A total of 1331 subjects were included in the study with a 60% female predominance and a sex ratio (male/female) of 0.7. The median age was 40 years (Q1 = 32 years; Q3 = 53 years) with a range of 25 and 98 years. The prevalence of hyperglycemia was 4.6%. In multivariate analysis, advanced age (AOR = 1.03; 95%CI = 1.02–1.73; p = 0.004), male sex (AOR = 2.93; 95%CI = 1.49–5.84; p = 0.023), monthly income> 105,000 FCFA (AOR = 2.63; 95%CI = 1.24–5.63; p = 0.030), abdominal obesity (AOR = 2.80; 95%CI = 1.29–6.16; p = 0.007, and obesity (AOR = 1.68; 95%CI = 0.75–3.59; p = 0.004) were statistically associated with hyperglycemia.

Conclusion

The prevalence of hyperglycemia is not negligible in rural areas in Benin. Our study found that older age, male gender, high income, abdominal obesity, and obesity are determining factors in its occurrence.
Interaction of fungal lipase with potential phytotherapeutics
Authors: Naz Farheen , Khan Imran , Islam Asimul , Khan Luqman Ahmad
Published: May 2022

Interaction of thymol, carvacrol and linalool with fungal lipase and Human Serum Albumin (HSA) have been investigated employing UV-Vis spectroscopy Fluorescence and Circular dichroism spectroscopy (CD) along with docking studies. Thymol, carvacrol and linalool displayed approximately 50% inhibition at 1.5 mmol/litre concentrations using para-nitrophenyl palmitate (pNPP). UV-Vis spectroscopy give evidence of the formation of lipase-linalool, lipase-carvacrol and lipase—thymol complex at the ground state. Three molecules also showed complex formation with HSA at the ground state. Fluorescence spectroscopy shows strong binding of lipase to thymol (Ka of 2.6 x 109 M-1) as compared to carvacrol (4.66 x 107 M-1) and linalool (5.3 x 103 M-1). Number of binding sites showing stoichiometry of association process on lipase is found to be 2.52 (thymol) compared to 2.04 (carvacrol) and 1.12 (linalool). Secondary structure analysis by CD spectroscopy results, following 24 hours incubation at 25°C, with thymol, carvacrol and linalool revealed decrease in negative ellipticity for lipase indicating loss in helical structure as compared with the native protein. The lowering in negative ellipticity was in the order of thymol > carvacrol > linalool. Fluorescence spectra following binding of all three molecules with HSA caused blue shift which suggests the compaction of the HSA structure. Association constant of thymol and HSA is 9.6 x 108 M-1 which along with ‘n’ value of 2.41 suggests strong association and stable complex formation, association constant for carvacrol and linalool was in range of 107 and 103 respectively. Docking results give further insight into strong binding of thymol, carvacrol and linalool with lipase having free energy of binding as -7.1 kcal/mol, -5.0 kcal/mol and -5.2 kcal/mol respectively. To conclude, fungal lipases can be attractive target for controlling their growth and pathogenicity. Employing UV-Vis, Fluorescence and Circular dichroism spectroscopy we have shown that thymol, carvacrol and linalool strongly bind and disrupt structure of fungal lipase, these three phytochemicals also bind well with HSA. Based on disruption of lipase structure and its binding nature with HSA, we concluded thymol as a best anti-lipase molecule among three molecules tested. Results of Fluorescence and CD spectroscopy taken together suggests that thymol and carvacrol are profound disrupter of lipase structure.
Spatio-temporal prediction and reconstruction network for video anomaly detection
Authors: Liu Ting , Zhang Chengqing , Niu Xiaodong , Wang Liming
Published: May 2022

The existing anomaly detection methods can be divided into two popular models based on reconstruction or future frame prediction. Due to the strong learning capacity, reconstruction approach can hardly generate significant reconstruction errors for anomalies, whereas future frame prediction approach is sensitive to noise in complicated scenarios. Therefore, a solution has been proposed by balancing the merits and demerits of the two models. However, most methods relied on single-scale information to capture spatial features and lacked temporal continuity between the video frames, affecting anomaly detection accuracy. Thus, we propose a novel method to improve anomaly detection performance. Because of the objects of various scales in each video, we select different receptive fields to extract comprehensive spatial features by the hybrid dilated convolution (HDC) module. Meanwhile, the deeper bidirectional convolutional long short-term memory (DB-ConvLSTM) module can remember the temporal information between the consecutive frames. Experiments prove that our method can detect abnormalities in various video scenes more accurately than the state-of-the-art methods in the anomaly-detection task.
The relationship between new PCR positive cases and going out in public during the COVID-19 epidemic in Japan
Authors: Takahashi Hiromichi , Terada Iori , Higuchi Takuya , Takada Daisuke , Shin Jung-ho , Kunisawa Susumu , Imanaka Yuichi
Published: May 2022

The suppression of the first wave of COVID-19 in Japan is assumedly attributed to people’s increased risk perception after acquiring information from the government and media reports. In this study, going out in public amidst the spread of COVID-19 infections was investigated by examining new polymerase chain reaction (PCR) positive cases of COVID-19 and its relationship to four indicators of people going out in public (the people flow, the index of web searches for going outside, the number of times people browse restaurants, and the number of hotel guests, from the Regional Economic and Social Analysis System (V-RESAS). Two waves of COVID-19 infections were examined using cross-correlation analysis. In the first wave, all four indicators of going out changed to be opposite the change in new PCR positive cases, showing a lag period of –1 to +6 weeks. In the second wave, the same relationship was only observed for the index of web searches for going outside, and two indicators showed the positive lag period of +6 to +12 weeks after the change in new PCR positive cases. Moreover, each indicator in the second wave changed differently compared to the first wave. The complexity of people’s behaviors around going out increased in the second wave, when policies and campaigns were implemented and people’s attitudes were thought to have changed. In conclusion, the results suggest that policies may have influenced people’s mobility, rather than the number of new PCR positive cases.
Increased expression of SPRR1A is associated with a poor prognosis in pancreatic ductal adenocarcinoma
Authors: Yamakawa Kohei , Koyanagi-Aoi Michiyo , Uehara Keiichiro , Masuda Atsuhiro , Yanagimoto Hiroaki , Toyama Hirochika , Fukumoto Takumi , Kodama Yuzo , Aoi Takashi
Published: May 2022

Objectives

Small proline-rich protein 1A (SPRR1A) is recognized as a squamous differentiation marker but is also upregulated in some non-squamous cancers. However, its expression in pancreatic ductal adenocarcinoma (PDAC) has not been investigated. This study elucidated the expression of SPRR1A in PDAC and its effect on the prognosis and malignant behavior of PDAC.

Methods

We examined the SPRR1A expression by immunohistochemistry in 86 surgical PDAC cases and revealed the relationship between its expression and the prognosis of the PDAC patients. Furthermore, we overexpressed SPRR1A in pancreatic cancer cell lines (PK-1 and Panc-1) and assessed the phenotype and gene expression changes in vitro.

Results

Among the 84 cases, excluding 2 with squamous differentiation, 31 (36.9%) had a high SPRR1A expression. The overall survival (median 22.1 months vs. 33.6 months, p = 0.0357) and recurrence-free survival (median 10.7 months vs. 15.5 months, p = 0.0298) were significantly lower in the high-SPRR1A-expression group than in the low-SPRR1A-expression group. A multivariate analysis indicated that a high SPRR1A expression (HR 1.706, 95% CI 1.018 to 2.862, p = 0.0427) and residual tumor status (HR 2.687, 95% CI 1.487 to 4.855, p = 0.00106) were independent prognostic factors. The analysis of TCGA transcriptome data demonstrated that the high-SPRR1A-expression group had a significantly worse prognosis than the low-SPRR1A-expression group, which supported our data. SPRR1A overexpression in PK-1 and Panc-1 did not result in remarkable changes to in vitro phenotypes, such as the cell proliferation, chemo-resistance, EMT, migration or global gene expression.

Conclusion

Increased expression of SPRR1A is associated with a poor prognosis in PDAC and may serve as a novel prognostic marker. However, our in vitro study suggests that the SPRR1A expression may be a consequence, not a cause, of the aggressive behavior of PDAC.
Cardio PyMEA: A user-friendly, open-source Python application for cardiomyocyte microelectrode array analysis
Authors: Dunham Christopher S. , Mackenzie Madelynn E. , Nakano Haruko , Kim Alexis R. , Nakano Atsushi , Stieg Adam Z. , Gimzewski James K.
Published: May 2022

Open source analytical software for the analysis of electrophysiological cardiomyocyte data offers a variety of new functionalities to complement closed-source, proprietary tools. Here, we present the Cardio PyMEA application, a free, modifiable, and open source program for the analysis of microelectrode array (MEA) data obtained from cardiomyocyte cultures. Major software capabilities include: beat detection; pacemaker origin estimation; beat amplitude and interval; local activation time, upstroke velocity, and conduction velocity; analysis of cardiomyocyte property-distance relationships; and robust power law analysis of pacemaker spatiotemporal instability. Cardio PyMEA was written entirely in Python 3 to provide an accessible, integrated workflow that possesses a user-friendly graphical user interface (GUI) written in PyQt5 to allow for performant, cross-platform utilization. This application makes use of object-oriented programming (OOP) principles to facilitate the relatively straightforward incorporation of custom functionalities, e.g. power law analysis, that suit the needs of the user. Cardio PyMEA is available as an open source application under the terms of the GNU General Public License (GPL). The source code for Cardio PyMEA can be downloaded from Github at the following repository: https://github.com/csdunhamUC/cardio_pymea.
Systematic screening for advanced liver fibrosis in patients with coronary artery disease: The CORONASH study
Authors: Thévenot Thierry , Vendeville Sophie , Weil Delphine , Akkouche Linda , Calame Paul , Canivet Clémence M. , Vanlemmens Claire , Richou Carine , Cervoni Jean-Paul , Seronde Marie-France , Di Martino Vincent , Boursier Jérôme
Published: May 2022

Although coronary artery disease (CAD) and advanced liver fibrosis (AdLF) are commonly associated in patients with non-alcoholic fatty liver disease (NAFLD), the prevalence of AdLF and the diagnostic performance of non-invasive fibrosis tests (NITs) in CAD patients remains unknown. We aimed to prospectively screen for AdLF in patients with documented CAD using NITs and Fibroscan. High and intermediate zones of NITs were combined to define AdLF. AdLF was suspected whenever APRI ≥ 0.5, Forns index ≥ 4.2, NAFLD fibrosis score (NFS) ≥ -1.455/0.12 for age </≥ 65 yrs), Fib4 (≥ 1.30/2.0 for age </≥ 65 yrs) and eLIFT≥ 8. A presumed AdLF assessed by Fibroscan ≥ 8 kPa was the primary outcome measure. Results were given on the basis of intent-to-diagnose liver stiffness ≥ 8 kPa. Among 189 patients (age 60±7years), 10 (5.3%) had a Fibroscan ≥ 8 kPa, of whom 5 underwent liver biopsy (F3/F4: n = 3; no fibrosis: n = 2). AdLF was suspected in 31% of cases using eLIFT (specificity, Sp 70%), 85% with Forns (Sp 16%), 38% with NFS (Sp 63%), 25% with Fib4 (Sp 74%), and 10% with APRI (Sp 91%). In 149 patients “at-risk” of NAFLD (i.e., elevated ALT or diabetes or hypertriglyceridemia or BMI ≥25 kg/m2), AdLF ranged between 10% (APRI) to 84% (Forns). In this subgroup, the most efficient NITs to predict Fibroscan ≥ 8 kPa were eLIFT (Se 60%, Sp 70%) and NFS (Se 70%, Sp 60%). Finally, in CAD patients with risk factors for NAFLD, NFS or the more user-friendly eLIFT are the most attractive first-line biochemical NITs to discriminate good candidates for Fibroscan.
Predicting risks of low birth weight in Bangladesh with machine learning
Authors: Islam Pollob S. M. Ashikul , Abedin Md. Menhazul , Islam Md. Touhidul , Islam Md. Merajul , Maniruzzaman Md.
Published: May 2022

Background and objective

Low birth weight is one of the primary causes of child mortality and several diseases of future life in developing countries, especially in Southern Asia. The main objective of this study is to determine the risk factors of low birth weight and predict low birth weight babies based on machine learning algorithms.

Materials and methods

Low birth weight data has been taken from the Bangladesh Demographic and Health Survey, 2017–18, which had 2351 respondents. The risk factors associated with low birth weight were investigated using binary logistic regression. Two machine learning-based classifiers (logistic regression and decision tree) were adopted to characterize and predict low birth weight. The model performances were evaluated by accuracy, sensitivity, specificity, positive predictive value, negative predictive value, and area under the curve.

Results

The average percentage of low birth weight in Bangladesh was 16.2%. The respondent’s region, education, wealth index, height, twin child, and alive child were statistically significant risk factors for low birth weight babies. The logistic regression-based classifier performed 87.6% accuracy and 0.59 area under the curve for holdout (90:10) cross-validation, whereas the decision tree performed 85.4% accuracy and 0.55 area under the curve.

Conclusions

Logistic regression-based classifier provided the most accurate classification of low birth weight babies and has the highest accuracy. This study’s findings indicate the necessity for an efficient, cost-effective, and integrated complementary approach to reduce and correctly predict low birth weight babies in Bangladesh.
Large scale across-breed genome-wide association study reveals a variant in HMGA2 associated with inguinal cryptorchidism risk in dogs
Authors: Blades Matthew , Freyer Jamie , Donner Jonas , Chodroff Foran Rebecca , Forman Oliver P.
Published: May 2022

Cryptorchidism is the most common congenital sex development disorder in dogs. Despite this, little progress has been made in understanding its genetic background. Extensive genetic testing of dogs through consumer and veterinary channels using a high-density SNP genotyping microarray coupled with links to clinical records presents the opportunity for a large-scale genome-wide association study to elucidate the molecular risk factors associated with cryptorchidism in dogs. Using an inter-breed genome-wide association study approach, a significant statistical association on canine chromosome 10 was identified, with the top SNP pinpointing a variant of HMGA2 previously associated with adult weight variance. In further analysis we show that incidence of cryptorchidism is skewed towards smaller dogs in concordance with the identified variant’s previous association with adult weight. This study represents the first putative variant to be associated with cryptorchidism in dogs.
Kinin B1 receptor deficiency protects mice fed by cafeteria diet from abnormal glucose homeostasis
Authors: Correia Poliana E. , Gomes Clarissa B. , Bandeira Vinicius A. , Marten Thais , Natividade Gabriella R. , Merello Paula , Tozawa Erica , Cerski Carlos T. S. , Budu Alexandre , Araújo Ronaldo , Arbo Bruno D. , Ribeiro Maria Flávia M. , Barros Carlos C. , Gerchman Fernando
Published: May 2022

The kallikrein–kinin system has been implicated in body weight and glucose homeostasis. Their major effectors act by binding to the kinin B2 and B1 receptors. It was assessed the role of the kinin B1 receptor in weight and glucose homeostasis in B1 receptor knockout mice (B1RKO) subjected to a cafeteria diet (CAF). Wild-type (WT) and B1RKO male mice (C57BL/6 background; 8 weeks old) were fed a standard diet (SD) or CAF for 14 weeks, ad libitum, and four groups were formed: WT-SD; B1RKO-SD; WT-CAF; B1RKO-CAF. Body weight and food intake were assessed weekly. It was performed glucose tolerance (GTT) and insulin tolerance tests (ITT), and HOMA-IR, HOMA-β and HOMA-β* 1/HOMA-IR were calculated. Islets from WT and B1RKO were isolated in order to measure the insulin secretion. Western blot was used to assess the hepatic AKT phosphorylation and qPCR to assess gene expression. CAF induced a higher body mass gain in B1RKO compared to WT mice. CAF diet increased epididymal fat depot mass, hepatic fat infiltration and hepatic AKT phosphorylation in both genotypes. However, B1RKO mice presented lower glycemic response during GTT when fed with CAF, and a lower glucose decrease in the ITT. This higher resistance was overcomed with higher insulin secretion when stimulated by high glucose, resulting in higher glucose uptake in the GTT when submitted to CAF, despite lower insulin sensitivity. Islets from B1RKO delivered 4 times more insulin in 3-month-old mice than islets from WT. The higher insulin disposition index and high insulin delivery of B1RKO can explain the decreased glucose excursion during GTT. In conclusion, CAF increased the β-cell function in B1RKO mice, compensated by the diet-induced insulin resistance and resulting in a healthier glycemic response despite the higher weight gain.
Acquired chemoresistance drives spatial heterogeneity, chemoprotection and collective migration in pancreatic tumor spheroids
Authors: Thege Fredrik I. , Cardle Ian I. , Gruber Conor N. , Siemann Megan J. , Cong Sophie , Wittmann Katharina , Love Justin , Kirby Brian J.
Published: May 2022

Tumors display rich cellular heterogeneity and typically consist of multiple co-existing clones with distinct genotypic and phenotypic characteristics. The acquisition of resistance to chemotherapy has been shown to contribute to the development of aggressive cancer traits, such as increased migration, invasion and stemness. It has been hypothesized that collective cellular behavior and cooperation of cancer cell populations may directly contribute to disease progression and lack of response to treatment. Here we show that the spontaneous emergence of chemoresistance in a cancer cell population exposed to the selective pressure of a chemotherapeutic agent can result in the emergence of collective cell behavior, including cell-sorting, chemoprotection and collective migration. We derived several gemcitabine resistant subclones from the human pancreatic cancer cell line BxPC3 and determined that the observed chemoresistance was driven of a focal amplification of the chr11p15.4 genomic region, resulting in over-expression of the ribonucleotide reductase (RNR) subunit RRM1. Interestingly, these subclones display a rich cell-sorting behavior when cultured as mixed tumor spheroids. Furthermore, we show that chemoresistant cells are able to exert a chemoprotective effect on non-resistant cells in spheroid co-culture, whereas no protective effect is seen in conventional 2D culture. We also demonstrate that the co-culture of resistant and non-resistant cells leads to collective migration where resistant cells enable migration of otherwise non-migratory cells.
Outcomes of Retzius-sparing versus conventional robot-assisted radical prostatectomy: A KSER update series systematic review and meta-analysis
Authors: Chung Doo Yong , Jung Hae Do , Kim Do Kyung , Lee Min Ho , Lee Sin Woo , Paick Sunghyun , Lee Joo Yong , Jeon Seung Hyun
Published: May 2022

Background

Robotic‐assisted radical prostatectomy(RARP) is widely used to surgically treat of localized prostate cancer. Among RARP, retzius-sparing techniques(RS-RARP) are implemented through douglas pouch, not the existing conventional approach(C-RARP). We conducted an updated systematic review and meta-analysis including recent published papers.

Materials & methods

Systematic review was performed following the PRISMA guideline. PubMed, EMBASE, and Cochrane Library were searched up to August 2021. We conducted meta-analysis as follows; Participants, patients with biopsy-proven PCa; Interventions, Patients underwent C-RARP or RS-RALP; Outcomes, comparison of continence recovery rate, positive surgical margins(PSM), complication, operation time and estimated blood loss(EBL) included for analysis.

Results

Thirteen studies with a total of 2917 patients were included for meta-analysis. Among them, three were randomized controlled trials (RCT) studies and the rest were non-RCT studies. Incontinence was analyzed with zero pad and safety pad, respectively. There showed a statistically significant advantage for RS-RARP in terms of continence recovery at 1 month(0 pad; OR 0.28, (0.16–0.47), safety-pad; OR 0.12 (0.07–0.22), p<0.001), as well as at 3 months(0 pad; OR 0.31 (0.18–0.53), safety-pad; OR 0.23 (0.14–0.40) p<0.001), 6 months(0 pad; OR 0.29 (0.17–0.51), safety-pad; OR 0.13 (0.06–0.27), p<0.001). And after 12 months, RS-RARP showed better results only in the safety-pad(0 pad; OR 0.64 (0.35–1.18), p = 0.15, safety-pad; OR 0.12 (0.04–0.36), p<0.001). In PSM, there was no statistical difference between two group at overall stage, but RS-RARP was observed to be higher than C-RARP in pT3 subgroup analysis(OR 0.74 (0.55–0.99), p = 0.047) (Fig 1). Whereas, there was no significant difference between the two groups in complication, operation time, and EBL.

Conclusions

Our analysis showed that RS-RARP is superior about early continence recovery than C-RARP. However, RS-RARP showed relatively high PSM in locally advanced PCa of pT3 or above. Therefore, although RS-RARP has few advantages about functional outcomes, we think that caution should be exercised when approaching patients with high-risk local diseases.
Unveiling the egg microbiota of the loggerhead sea turtle Caretta caretta in nesting beaches of the Mediterranean Sea
Authors: Vecchioni Luca , Pace Antonino , Sucato Arianna , Berlinghieri Flavia , Cambera Irene , Visconti Giulia , Hochscheid Sandra , Arculeo Marco , Alduina Rosa
Published: May 2022

Microbes have central roles in the development and health of animals, being the introduction of specific microbial species a potential conservation strategy to protect animals from emerging diseases. Thus, insight into the microbiota of the species and their habitats is essential. In this manuscript, we report for the first time the bacterial composition of all the components (eggshells of hatched and unhatched eggs, internal content of unhatched eggs, intestinal content of hatchling and pipping sea turtles, and sand) of three nesting beaches of Caretta caretta along the Italian coasts of the Mediterranean Sea. The analysis of 26 amplicon samples was carried out using next-generation sequencing analysis, targeting V3–V4 regions of the bacterial 16S rRNA gene. Samples featured mainly Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes, whose percentages depended on the sample type. Our results showed that, although from different sampling sites, the internal content of the unhatched eggs, intestinal content of hatchling and pipping sea turtles share the microbiota, which was yet different from that of eggshells and sand of the same nesting beach. This study suggests the maternal and environmental influence alongside a protective role of eggshells in shaping the egg microbiota of Caretta caretta sea turtles.
Takotsubo cardiomyopathy in patients suffering from acute non-traumatic subarachnoid hemorrhage—A single center follow-up study
Authors: Molnár Csilla , Gál Judit , Szántó Dorottya , Fülöp László , Szegedi Andrea , Siró Péter , Nagy Endre V. , Lengyel Szabolcs , Kappelmayer János , Fülesdi Béla
Published: May 2022

Background

Takotsubo cardiomyopathy (TTC) is an important complication of subarachnoid hemorrhage (SAH), that may delay surgical or endovascular treatment and may influence patient outcome. This prospective follow-up study intended to collect data on the prevalence, severity, influencing factors and long-term outcome of TTC in patients suffering from non-traumatic SAH.

Methods

Consecutive patients admitted with the diagnosis of non-traumatic SAH were included. Intitial assessment consisted of cranial CT, Hunt-Hess, Fisher and WFNS scoring, 12-lead ECG, transthoracic echocardiography (TTE), transcranial duplex sonography and collecting laboratory parameters (CK, CK-MB, cardiac troponin T, NT-proBNP and urine metanephrine and normetanephrine). Diagnosis of TTC was based on modified Mayo criteria. TTC patients were dichotomized to mild and severe forms. Follow-up of TTE, Glasgow Outcome Scale assessment, Barthel’s and Karnofsky scoring occurred on days 30 and 180.

Results

One hundred thirty six patients were included. The incidence of TTC in the entire cohort was 28.7%; of them, 20.6% and 8.1% were mild and severe, respectively. TTC was more frequent in females (30/39; 77%) than in males (9/39; 23%) and was more severe. The occurrence of TTC was related to mFisher scores and WFNS scores. Although the severity of TTC was related to mFisher score, Hunt-Hess score, WFNS score and GCS, multivariate analysis showed the strongest relationship with mFisher scores. Ejection fraction differences between groups were present on day 30, but disappeared by day 180, whereas wall motion score index was still higher in the severe TTC group at day 180. By the end of the follow-up period (180 days), 70 (74.5%) patients survived in the non-TTC, 22 (81.5%) in the mild TTC and 3 (27%) in the severe TTC group (n = 11) (p = 0.002). At day 180, GOS, Barthel, and Karnofsky outcome scores were higher in patients in the control (non-TTC) and the mild TTC groups than in the severe TTC group.

Conclusions

Takotsubo cardiomyopathy is a frequent finding in patients with SAH, and severe TTC may be present in 8% of SAH cases. The severity of TTC may be an independent predictor of mortality and outcome at 6 months after disease onset. Therefore, a regular follow-up of ECG and TTE abnormalities is warranted in patients with subrachnoid hemorrhage for early detection of TTC.

Trial registration

The study was registered at the Clinical Trials Register under the registration number of NCT02659878 (date of registration: January 21, 2016).
Long-term impact of invasive meningococcal disease in children: SEINE study protocol
Authors: Baloche Alexiane , Jung Camille , Levy Michael , Elbez-Rubinstein Annie , Béchet Stéphane , Layouni Ines , Monguillot Geneviève , Taha Muhamed Kheir , Cohen Robert , Levy Corinne
Published: May 2022

Introduction

Invasive meningococcal disease (IMD) is still an important cause of mortality in children and survivors can have significant long-term disabling sequelae. There are few prospective studies looking at the long term neuropsychological and developmental consequences of IMD in surviving children, and the rate of sequelae may be underestimated. The SEINE study aims to have a more reliable estimate of the real rate of sequelae by assessing the long-term physical, neuropsychological, learning disorders and sensory sequelae of IMD in children and adolescents and by assessing the post-traumatic stress in parents.

Methods and analysis

The SEINE study is a multicentre, prospective, non-randomized, interventional study based on the French bacterial meningitis surveillance network. The study will include 100 children aged from birth to 15 years old, hospitalized in a Paris area paediatric ward for a meningococcal meningitis or a purpura fulminans between 2010 and 2019. The first outcome will assess long-term sequelae (physical, neurological, or sensory) measured by a general clinical and neurological examination, a neurocognitive assessment, learning development, a pure tone audiometry and an ophthalmic examination. The second outcome will assess the long-term post-traumatic stress in parents measured by the Impact of Event Scare Revised questionnaire.

Perspectives

By providing a better estimation of the rate of sequelae in children and offering an adapted follow-up of these children, we believe that the SEINE study will help to improve the management of patients surviving IMD.

Trial registration number

NCT04685850.
Accuracy Assessment of Kriging, artificial neural network, and a hybrid approach integrating spatial and terrain data in estimating and mapping of soil organic carbon
Authors: Kılıç Miraç , Gündoğan Recep , Günal Hikmet , Cemek Bilal
Published: May 2022

This study aimed to produce a soil organic carbon (SOC) content map with high accuracy and spatial resolution using the most effective factors in the model. The spatial SOC estimation success of Inverse Distance Weighting (IDW), Ordinary Kriging (OK), Empirical Bayesian Kriging (EBK), Multi-Layered Perception Network (MLP) and MLP-OK Hybrid models were compared to obtain the most reliable model in estimating the SOC content. The study area was located in Besni district in the Southeastern Anatolia Region of Turkey. Total of 132 surface (0–30 cm) soil samples were collected from the covers 1330 km2 land and analyzed for SOC, lime, clay and sand content and soil reaction included in the estimation models. Mean annual precipitation and temperature, elevation, compound topographic index, enhanced vegetation and normalized difference vegetation index, were also used as the inputs in the modelling. The spatial distribution of SOC was determined using a MLP and a two-stage ensemble model (MLP-OK) combining the estimation of OK residuals. Soil surveys and covariates were used to train and validate the MLP-OK hybrid model. The MLP-OK model provided a more accurate estimation of SOC content with minimal estimation errors (ME: -0.028, 45 MAE: 0.042, RMSE: 0.066) for validation points compared to the other models. The MLP-OK model outperformed other models by 75.09 to 77.92%. The MLP-OK model estimated the lower and upper limits of the estimated and the measured values in a consistent manner compared to the other models. The spatial distribution map of SOC content obtained by ANN-kriging approach was significantly affected by ancillary variables, and revealed more detail than other interpolation methods in the northern, central, southwestern and southeastern parts of the study area. The results revealed that the assembling of MLP with OK model can contribute to obtain more reliable regional, national and global spatial soil information.