bluuebunny/crossref_metadata_2025 huggingface dataset:
Medium-term Load Forecasting Method with Improved Deep Belief Network for Renewable Energy
Authors: Liang Yan , Zhi Li , Haiwei Yu
Published: April 2022

With the continuous transition of the traditional power system to the newpower system, the composition of the power generation side in the powersystem has gradually begun to be dominated by renewable energy (at leastmore than 50%). Among the renewable energy sources, wind power is themost susceptible to weather and environmental inﬂuences. These factorsincrease the complexity of the power generation mode, and put forwardhigher requirements for the accuracy and stability of load forecasting. Thispaper proposes a medium-term renewable energy load forecasting methodbased on an improved deep belief network (IDBN-NN). The method includesthe construction of a deep belief network, the layer-by-layer pre-trainingand ﬁne-tuning of model parameters, and the application of the model.In the process of model parameter pre-training, Gauss-Bernoulli RestrictedBoltzmann Machine (GB-RBM) is used as the ﬁrst part of the stacked deepbelief network, so that it can process multiple types of real-valued input data more effectively. In addition, IDBN-NN uses a combination of unsupervisedtraining and supervised training for pre-training. Finally, the actual load datais used to analyze the calculation example. When the number of RBM layersis 3, the number of fully connected layers is 1, and Dropout is equal to0.2, the MSE and loss values are optimal, which are 0.0037 and 0.0104,respectively. The experimental results show that the proposed method hashigher prediction accuracy when the training sample is large and the loadinﬂuencing factors are complex.
Fourier ptychography multi-parameter neural network with composite physical priori optimization
Authors: Yang Delong , Zhang Shaohui , Zheng Chuanjian , Zhou Guocheng , Cao Lei , Hu Yao , Hao Qun
Published: April 2022

Fourier ptychography microscopy(FPM) is a recently developed computational imaging approach for microscopic super-resolution imaging. By turning on each light-emitting-diode (LED) located on different position on the LED array sequentially and acquiring the corresponding images that contain different spatial frequency components, high spatial resolution and quantitative phase imaging can be achieved in the case of large field-of-view. Nevertheless, FPM has high requirements for the system construction and data acquisition processes, such as precise LEDs position, accurate focusing and appropriate exposure time, which brings many limitations to its practical applications. In this paper, inspired by artificial neural network, we propose a Fourier ptychography multi-parameter neural network (FPMN) with composite physical prior optimization. A hybrid parameter determination strategy combining physical imaging model and data-driven network training is proposed to recover the multi layers of the network corresponding to different physical parameters, including sample complex function, system pupil function, defocus distance, LED array position deviation and illumination intensity fluctuation, etc. Among these parameters, LED array position deviation is recovered based on the features of brightfield to darkfield transition low-resolution images while the others are recovered in the process of training of the neural network. The feasibility and effectiveness of FPMN are verified through simulations and actual experiments. Therefore FPMN can evidently reduce the requirement for practical applications of FPM.
Joint estimation of depth and motion from a monocular endoscopy image sequence using a multi-loss rebalancing network
Authors: Liu Shiyuan , Fan Jingfan , Song Dengpan , Fu Tianyu , Lin Yucong , Xiao Deqiang , Song Hong , Wang Yongtian , Yang Jian
Published: April 2022

Building an in vivo three-dimensional (3D) surface model from a monocular endoscopy is an effective technology to improve the intuitiveness and precision of clinical laparoscopic surgery. This paper proposes a multi-loss rebalancing-based method for joint estimation of depth and motion from a monocular endoscopy image sequence. The feature descriptors are used to provide monitoring signals for the depth estimation network and motion estimation network. The epipolar constraints of the sequence frame is considered in the neighborhood spatial information by depth estimation network to enhance the accuracy of depth estimation. The reprojection information of depth estimation is used to reconstruct the camera motion by motion estimation network with a multi-view relative pose fusion mechanism. The relative response loss, feature consistency loss, and epipolar consistency loss function are defined to improve the robustness and accuracy of the proposed unsupervised learning-based method. Evaluations are implemented on public datasets. The error of motion estimation in three scenes decreased by 42.1%,53.6%, and 50.2%, respectively. And the average error of 3D reconstruction is 6.456 ± 1.798mm. This demonstrates its capability to generate reliable depth estimation and trajectory reconstruction results for endoscopy images and meaningful applications in clinical.
Flexible chalcogenide glass large-core multimode fibers for hundred-watt-level mid-infrared 2-5 µm laser transmission
Authors: Qi Sisheng , Li Yuebing , Huang Zixuan , Ren He , Sun Wenjuan , Shi Jindan , Wang Fei , Shen Deyuan , Feng Xian , Yang Zhiyong
Published: April 2022

The rapidly-developed high-power mid-infrared 2-5 µm laser technology requires a compact, flexible low-loss glass fiber for power delivery or laser generation. With the broadest bandwidth of low-loss transmission window in mid-infrared region amongst all mid-infrared glass fibers, chalcogenide glass fiber is the best candidate covering the whole 2-5 µm range. Multi-hundred-watt high-power delivery for 5.4-µm CO laser was previously demonstrated in a multimode chalcogenide fiber with a 1-mm-diameter large core, at the cost of giving up one of the most desirable fiber advantages, the flexibility. Indeed, chalcogenide glass fibers with decent flexibility have never exhibited hundred-watt-level power transmitting capability in the 2-5 µm range. In this paper, we have experimentally demonstrated 100-watt-level power transmission in multimode As2S3 chalcogenide fibers, using a customized high-power 2-µm thulium doped silica fiber laser source. With effective forced cooling, the multimode As2S3 fiber with 200 µm core diameter can resist incident laser power of 120 W and deliver transmitted power of 63 W. Nano-sized scattering center related laser damage mechanism and the cylindrical heat transfer model have been proposed to explain the high-power damage process of chalcogenide glass fibers. The calculation is in good agreement with the experiments. It is promising to further enhance the transmitted power above 100 W in flexible chalcogenide glass large-core fibers.
Interlayer directional coupling thermo-optic waveguide switches based on functionalized epoxy-crosslinking polymers
Authors: Yue Jian , Wang Chunxue , Lin Hang , Ding Shuxiang , Shi Zuosen , Cui Zhanchen , Chen Changming , Zhang Daming
Published: April 2022

In this study, interlayer directional coupling (DC) thermo-optic (TO) waveguide switches were designed and fabricated using functionalized epoxy-crosslinking polymers. Fluorinated SU-8 (FSU-8) with a photo-initiating epoxy-crosslinking network was self-synthesized as a waveguide core material. A copolymer of methyl methacrylate and glycidyl methacrylate P(MMA-co-GMA) with a thermo-initiating epoxy crosslinking structure was self-synthesized as a waveguide cladding material. Compared with commercial pure SU-8 and PMMA, FSU-8 exhibited a lower absorption loss and P(MMA-co-GMA) exhibited a higher thermal stability. Using epoxy-crosslinking functionalized polymers, the structure of the waveguides and electrode heaters were optimized, and the performance parameters of the interlayer DC TO switches were simulated. At a signal wavelength of 1550 nm, the insertion loss, extinction ratio, and power consumption of the actual interlayer devices were measured as 6.7 dB, 15.6 dB, and 9 mW, respectively. The rising and falling response times of the TO switches were obtained as 631.6 µs and 362 µs, respectively. The self-leveling ability and solvent resistance characteristic of the epoxy-crosslinking network for FSU-8 and P(MMA-co-GMA) may guarantee the realization of interlayer DC TO waveguide switches. The proposed technique will be suitable for photonic integrated waveguide chips with multilayer stacking dynamic optical information interactions.
Chaotic physical layer encryption scheme based on phase ambiguity for a DMT system
Authors: Wang Xishuo , Li Zhipei , Zhang Qi , Pan Xiaolong , Gao Ran , Xin Xiangjun , Yao Haipeng , Tian Feng , Tian Qinghua , Wang Yongjun
Published: April 2022

Chaotic encryption is a promising scheme for physical layer security. By solving the multi-dimensional chaotic equations and transforming the obtained results, both bit-level and symbol-level encryption can be realized. One of the mainstream symbol-level encryption solutions is the constellation shifting (CS) scheme, which treats the chaotic sequence as artificial noise and adds it to the QAM signal sequence to achieve encryption. However, this scheme has several technical flaws in practical application, in terms of computational complexity and coexistence with blind equalization algorithm and the probabilistic shaping (PS) technique. In this paper, we propose a novel symbol-level encryption scheme based on phase ambiguity (PA), which converts the two sequences originally used to generate artificial noise into a set of phase rotation keys and complex conjugate keys, so that the encrypted symbols are still on the ideal constellation point coordinates. Simulation verification is carried out in a discrete multi-tone (DMT) system with 64QAM modulation. Results show that the proposed scheme can fully retain the shaping gain brought by the PS technique and avoid the error convergence of the blind equalizer. Moreover, the time required to solve the chaotic equations is only 38% of the CS scheme. Experimental verification is carried out, and the obtained results once again prove the superiority of the proposed encryption algorithm, which is a practical alternative for future physical layer secure optical communications.
Sensitivity enhancement of fiber optical polarimetric sensors using self-induced nonlinear phase modulation via the Kerr effect
Authors: Krarup Ole , Baker Chams , Chen Liang , Bao Xiaoyi
Published: April 2022

This work presents an analytical model accounting for the impact of optical polarization on the generation of frequency sidebands by the Kerr effect in a highly nonlinear fiber. Theoretical analysis shows that for a relative polarization angle, α, between two input lasers expressed on the Poincaré sphere, the optical power of the n
th
order sideband is proportional to cos 2n(α/2). This theoretical result enables a novel all-optical technique for interrogating changes in polarization with higher sensitivity than conventional measurement schemes using linear polarizers. The predicted theoretical relationship between the sideband power and the relative polarization angle is verified experimentally and sensitivity enhancement by a factor of 1.45 compared to a conventional polarimetric sensor is demonstrated for the 3rd order sideband. This novel nonlinear approach, which allows dynamic range to be traded for an enhanced ability to detect small polarization variations, has potential applications in fusion reactor monitoring, instrumentation and material characterization.
Electro-optic high-speed optical beam shifting based on a lithium niobate tapered waveguide
Authors: Shang Jumei , Chen Huajiang , Sui Zhan , Lin Qijing , Luo Kaiwen , Yu Lingyun , Qiu Wentao , Guan Heyuan , Chen Zhe , Lu Huihui
Published: April 2022

We propose an electro-optic on-chip beam shifting device based on gradient microstructured electrodes and an optical tapered waveguide fabricated using lithium niobate (LN). The distribution of refractive index variations of the optical waveguide can be electro-optically defined and tailored by the designed gradient microstructured electrodes, which directs the beam propagation and shifting. The length of the beam shifting device is 18 mm and the width of the waveguide is gradually increased from 8 μm to 80 μm. The functionality of the beam shifting device is experimentally demonstrated, and it is observed that it has an electro-optic tunability of 0.41 μm/V, and a high-speed response time of 19 ns (λ=1310 nm). This study can provide potential applications in optical switching and modulation, beam scanning and ranging, optical spatial communications, etc.
Co-phase state detection for segmented mirrors by dual-wavelength optical vortex phase-shifting interferometry
Authors: Yang Lili , Yang Dong , Yang Zhongming , Liu Zhaojun
Published: April 2022

The application of large-aperture telescopes requires the support of co-phase measurement techniques for segmented mirrors. This paper proposes a novel method to detect the co-phase state of segmented mirrors by applying a dual-wavelength phase-shifting interferometer based on optical vortex. Theory and experiments indicate that the wrapped phase map edges obtained by phase-shifting interference of the vortex beam are distributed in the form of a Fermat spiral. The piston error of the segmented mirrors corresponds to the rotation of the standard Fermat spiral center. In contrast, the tip/tilt error corresponds to the alteration of the center position of the deformed Fermat spiral. The rotation angle and the center position of the spiral are obtained by curve fitting, and the co-phase errors can be inversely solved. The experiments achieved an accuracy of approximately 4.04 nm in the piston and 0.16″ in the tip/tilt. The method avoids using complex lens arrays and devices, has an extended measurement range, high accuracy, and allows the co-phase errors between all sub-mirrors to be obtained in real-time. This study provides a novel and general method for detecting co-phase errors in a segmented primary mirror.
Giant photoinduced inverse spin Hall effect of the surface states in three dimensional topological insulators Bi2Te3 with different thickness
Authors: Wu Wenyi , Yu Jinling , Xia Lijia , Zhu Kejing , Zeng Xiaolin , Chen Yonghai , Yin Chunming , Cheng Shuying , Lai Yunfeng , He Ke
Published: April 2022

The photoinduced inverse spin Hall effect (PISHE) has been studied in three dimensional (3D) topological insulator (TI) Bi2Te3 thin films with different thicknesses (3, 5, 12 and 20 quintuple layer (QL)). The sign of the PISHE current flips only once in the 3- and 20-QL Bi2Te3 films, but it flips three times in the 5-, 7- and 12-QL samples. The three-times sign flip is due to the superposition of the PISHE current of the top and bottom surface states in Bi2Te3 films. By analyzing the x-ray photoelectron spectroscopy (XPS) of the Bi2Te3 films, we find that the top surface of the 3- and 20-QL Bi2Te3 films are severely oxidized, leading to only one sign flip in the PISHE. The PISHE contributed by the top and bottom surface states in Bi2Te3 films have been successfully separated by fitting a theoretical model to the PISHE current. The impact of the bulk states on PISHE current has been determined. The PISHE current is also measured at different light powers, and all the measurement results are in good agreement with the theoretical model. In addition, it is found that the PISHE current in Bi2Te3 films grown on Si substrate is more than two orders larger than that grown on SrTiO3 substrates, which can be attributed to the larger absorption coefficient for Bi2Te3/Si samples. It is revealed that the PISHE current in 3D TI Bi2Te3 is as large as 140 nA/W in the 3-QL Bi2Te3 film grown on Si substrate, which is more than one order larger than that reported in GaAs/AlGaAs heterojunction (about 2 nA/W) and GaN/AlGaN heterojunction (about 1.7 nA/W). The giant PISHE current demonstrates that the TIs with strong SOC may have good application prospects in spintronic devices with high spin-to-charge conversion efficiency.
Optical-feedback cavity-enhanced absorption spectroscopy for OH radical detection at 2.8 µm using a DFB diode laser
Authors: Yang Nana , Fang Bo , Zhao Weixiong , Wang Chunhui , Cheng Feihu , Hu Xiao , Chen Yang , Zhang Weijun , Ma Weiguang , Zhao Gang , Chen Weidong
Published: April 2022

We report the development of an optical-feedback cavity-enhanced absorption spectroscopy (OF-CEAS) instrument for OH detection at 2.8 μm using a DFB diode laser. Two different approaches, symmetry analysis and wavelength modulation, were performed to achieve laser frequency locking to the cavity mode. Compared with the symmetry analysis method, the wavelength modulation method continuously locked the laser frequency to the cavity mode and eliminated decoupling the laser from the cavity mode. A detection sensitivity of 1.7×10−9 cm-1 was achieved in a 25 s sampling time and was about 3 times better than that of the symmetry analysis method. The corresponding OH detection limit was ∼ 2×108 molecule/cm3. Further improvement can be achieved by using higher reflectivity mirrors and other high-sensitivity approaches, such as frequency modulation spectroscopy and Faraday rotation spectroscopy.
Broadband similariton generation in a mode-locked Yb-doped fiber laser
Authors: Zhao Zihao , Jin Lei , Set Sze Yun , Yamashita Shinji
Published: April 2022

We experimentally demonstrated a broadband similariton generated from a mode-locked Yb-doped fiber laser with dispersion compensation. The broadest spectrum was obtained by pushing the net dispersion to its limitation and fully exploiting the gain bandwidth. The spectrum was 115 nm broad in 10 dB bandwidth and 36 nm broad in 3 dB bandwidth. The output was 105 mW optical power at 545 mW pump power. Simulation combined with experiment was performed to investigate and confirm the mode-locking regime of the laser. Experimental observations agreed well with the numerical simulation. We believe our study provides a practical route for designing broadband mode-locked fiber lasers.
Integrated room temperature single-photon source for quantum key distribution: publisher’s note
Authors: Zeng Helen ZhiJie , Ngyuen Minh Anh Phan , Ai Xiaoyu , Bennet Adam , Solntsev Alexander S. , Laucht Arne , Al-Juboori Ali , Toth Milos , Mildren Richard P. , Malaney Robert , Aharonovich Igor
Published: April 2022

This publisher’s note contains a correction to Opt. Lett. 47, 1673 (2022)10.1364/OL.454450.
Satellite-assisted laser magnetometry with mesospheric sodium
Authors: Dang Tong , Klinger Emmanuel , Pedreros Bustos Felipe , Wickenbrock Arne , Holzlöhner Ronald , Budker Dmitry
Published: April 2022

Magnetic field sensing provides crucial insights into various geophysical phenomena such as atmospheric currents, crustal magnetism, and oceanic circulation. In this paper, a method for remote detection of magnetic fields using mesospheric sodium with an assisting satellite is proposed. Sodium atoms in the mesosphere are optically pumped with a ground-based laser beam. A satellite-borne detector is used to measure magneto-optical rotation of the polarization of a probe laser beam by the sodium atoms. This sensitive magnetometry method benefits from direct detection of laser photons and complements existing space- and aircraft-borne techniques by probing magnetic fields at upper-atmospheric altitudes inaccessible to those.
Generalizability challenges of mortality risk prediction models: A retrospective analysis on a multi-center database
Authors: Singh Harvineet , Mhasawade Vishwali , Chunara Rumi
Published: April 2022

Modern predictive models require large amounts of data for training and evaluation, absence of which may result in models that are specific to certain locations, populations in them and clinical practices. Yet, best practices for clinical risk prediction models have not yet considered such challenges to generalizability. Here we ask whether population- and group-level performance of mortality prediction models vary significantly when applied to hospitals or geographies different from the ones in which they are developed. Further, what characteristics of the datasets explain the performance variation? In this multi-center cross-sectional study, we analyzed electronic health records from 179 hospitals across the US with 70,126 hospitalizations from 2014 to 2015. Generalization gap, defined as difference between model performance metrics across hospitals, is computed for area under the receiver operating characteristic curve (AUC) and calibration slope. To assess model performance by the race variable, we report differences in false negative rates across groups. Data were also analyzed using a causal discovery algorithm “Fast Causal Inference” that infers paths of causal influence while identifying potential influences associated with unmeasured variables. When transferring models across hospitals, AUC at the test hospital ranged from 0.777 to 0.832 (1st-3rd quartile or IQR; median 0.801); calibration slope from 0.725 to 0.983 (IQR; median 0.853); and disparity in false negative rates from 0.046 to 0.168 (IQR; median 0.092). Distribution of all variable types (demography, vitals, and labs) differed significantly across hospitals and regions. The race variable also mediated differences in the relationship between clinical variables and mortality, by hospital/region. In conclusion, group-level performance should be assessed during generalizability checks to identify potential harms to the groups. Moreover, for developing methods to improve model performance in new environments, a better understanding and documentation of provenance of data and health processes are needed to identify and mitigate sources of variation.
Predicting the impact of environmental factors on citrus canker through multiple regression
Authors: Hameed Akhtar , Atiq Muhammad , Ahmed Zaheer , Rajput Nasir Ahmed , Younas Muhammad , Rehman Abdul , Alam Muhammad Waqar , Sarfaraz Sohaib , Liaqat Nadia , Fatima Kaneez , Tariq Komal , Jameel Sahar , Ghazali Hafiz Muhammad Zia Ullah , Vachova Pavla , Salmen Saleh H. , Ansari Mohammad Javed
Published: April 2022

Climatic conditions play a significant role in the development of citrus canker caused by Xanthomonas citri pv. citri (Xcc). Citrus canker is regarded as one of the major threats being faced by citrus industry in citrus growing countries of the world. Climatic factors exert significant impacts on growth stage, host susceptibility, succulence, vigor, survival, multiplication rate, pathogen dispersion, spore penetration rate, and spore germination. Predicting the impacts of climatic factors on these traits could aid in the development of effective management strategies against the disease. This study predicted the impacts of environmental variables, i.e., temperature, relative humidity, rainfall, and wind speed the development of citrus canker through multiple regression. These environmental variables were correlated with the development of canker on thirty (30) citrus varieties during 2017 to 2020. Significant positive correlations were noted among environment variables and disease development modeled through multiple regression model (Y = +24.02 + 0.5585 X1 + 0.2997 X2 + 0.3534 X3 + 3.590 X4 + 1.639 X5). Goodness of fit of the model was signified by coefficient determination value (97.5%). Results revealed the optimum values of environmental variables, i.e., maximum temperature (37°C), minimum temperature (27°C), relative humidity (55%), rainfall (4.7–7.1 mm) and wind speed (8 Km/h), which were conducive for the development of citrus canker. Current study would help researchers in designing better management strategies against citrus canker disease under changing climatic conditions in the future.
Reproducible disease phenotyping at scale: Example of coronary artery disease in UK Biobank
Authors: Patel Riyaz S. , Denaxas Spiros , Howe Laurence J. , Eggo Rosalind M. , Shah Anoop D. , Allen Naomi E. , Danesh John , Hingorani Aroon , Sudlow Cathie , Hemingway Harry
Published: April 2022

Importance

A lack of internationally agreed standards for combining available data sources at scale risks inconsistent disease phenotyping limiting research reproducibility.

Objective

To develop and then evaluate if a rules-based algorithm can identify coronary artery disease (CAD) sub-phenotypes using electronic health records (EHR) and questionnaire data from UK Biobank (UKB).

Design

Case-control and cohort study.

Setting

Prospective cohort study of 502K individuals aged 40–69 years recruited between 2006–2010 into the UK Biobank with linked hospitalization and mortality data and genotyping.

Participants

We included all individuals for phenotyping into 6 predefined CAD phenotypes using hospital admission and procedure codes, mortality records and baseline survey data. Of these, 408,470 unrelated individuals of European descent had a polygenic risk score (PRS) for CAD estimated.

Exposure

CAD Phenotypes.

Main outcomes and measures

Association with baseline risk factors, mortality (n = 14,419 over 7.8 years median f/u), and a PRS for CAD.

Results

The algorithm classified individuals with CAD into prevalent MI (n = 4,900); incident MI (n = 4,621), prevalent CAD without MI (n = 10,910), incident CAD without MI (n = 8,668), prevalent self-reported MI (n = 2,754); prevalent self-reported CAD without MI (n = 5,623), yielding 37,476 individuals with any type of CAD. Risk factors were similar across the six CAD phenotypes, except for fewer men in the self-reported CAD without MI group (46.7% v 70.1% for the overall group). In age- and sex- adjusted survival analyses, mortality was highest following incident MI (HR 6.66, 95% CI 6.07–7.31) and lowest for prevalent self-reported CAD without MI at baseline (HR 1.31, 95% CI 1.15–1.50) compared to disease-free controls. There were similar graded associations across the six phenotypes per SD increase in PRS, with the strongest association for prevalent MI (OR 1.50, 95% CI 1.46–1.55) and the weakest for prevalent self-reported CAD without MI (OR 1.08, 95% CI 1.05–1.12). The algorithm is available in the open phenotype HDR UK phenotype library (https://portal.caliberresearch.org/).

Conclusions

An algorithmic, EHR-based approach distinguished six phenotypes of CAD with distinct survival and PRS associations, supporting adoption of open approaches to help standardize CAD phenotyping and its wider potential value for reproducible research in other conditions.
Detection of SARS-CoV-2 infection by microRNA profiling of the upper respiratory tract
Authors: Farr Ryan J. , Rootes Christina L. , Stenos John , Foo Chwan Hong , Cowled Christopher , Stewart Cameron R.
Published: April 2022

Host biomarkers are increasingly being considered as tools for improved COVID-19 detection and prognosis. We recently profiled circulating host-encoded microRNA (miRNAs) during SARS-CoV-2 infection, revealing a signature that classified COVID-19 cases with 99.9% accuracy. Here we sought to develop a signature suited for clinical application by analyzing specimens collected using minimally invasive procedures. Eight miRNAs displayed altered expression in anterior nasal tissues from COVID-19 patients, with miR-142-3p, a negative regulator of interleukin-6 (IL-6) production, the most strongly upregulated. Supervised machine learning analysis revealed that a three-miRNA signature (miR-30c-2-3p, miR-628-3p and miR-93-5p) independently classifies COVID-19 cases with 100% accuracy. This study further defines the host miRNA response to SARS-CoV-2 infection and identifies candidate biomarkers for improved COVID-19 detection.
Vertical transmission of attaching and invasive E. coli from the dam to neonatal mice predisposes to more severe colitis following exposure to a colitic insult later in life
Authors: Wymore Brand Meghan , Proctor Alexandra L. , Hostetter Jesse M. , Zhou Naihui , Friedberg Iddo , Jergens Albert E. , Phillips Gregory J. , Wannemuehler Michael J.
Published: April 2022

The gastrointestinal microbiota begins to be acquired at birth and continually matures through early adolescence. Despite the relevance for gut health, few studies have evaluated the impact of pathobiont colonization of neonates on the severity of colitis later in life. LF82 is an adherent invasiveE.colistrain associated with ileal Crohn’s disease. The aim of this study was to evaluate the severity of dextran sodium sulfate (DSS)-induced colitis in mice followingE.coliLF82 colonization. Gnotobiotic mice harboring the altered Schaedler flora (ASF) were used as the model. WhileE.coliLF82 is neither adherent nor invasive, it was been demonstrated that adult ASF mice colonized withE.coliLF82 develop more severe DSS-induced colitis compared to control ASF mice treated with DSS. Therefore, we hypothesized thatE.coliLF82 colonization of neonatal ASF mice would reduce the severity of DSS-induced inflammation compared to adult ASF mice colonized withE.coliLF82. To test this hypothesis, adult ASF mice were colonized withE.coliLF82 and bred to produce offspring (LF82N) that were vertically colonized with LF82. LF82Nand adult-colonized (LF82A) mice were given 2.0% DSS in drinking water for seven days to trigger colitis. More severe inflammatory lesions were observed in the LF82N+ DSS mice when compared to LF82A+ DSS mice, and were characterized as transmural in most of the LF82N+ DSS mice. Colitis was accompanied by secretion of proinflammatory cytokines (IFNγ, IL-17) and specific mRNA transcripts within the colonic mucosa. Using 16S rRNA gene amplicon sequencing, LF82 colonization did not induce significant changes in the ASF community; however, minimal changes in spatial redistribution by fluorescent in situ hybridization were observed. These results suggest that the age at which mice were colonized withE.coliLF82 pathobiont differentially impacted severity of subsequent colitic events.
A Monte Carlo analysis of false inference in spatial conflict event studies
Authors: Schutte Sebastian , Kelling Claire
Published: April 2022

Spatial event data is heavily used in contemporary research on political violence. Such data are oftentimes mapped onto grid-cells or administrative regions to draw inference about the determinants of conflict intensity. This setup can identify geographic determinants of violence, but is also prone to methodological issues. Problems resulting from spatial aggregation and dependence have been raised in methodological studies, but are rarely accounted for in applied research. As a consequence, we know little about the empirical relevance of these general problems and the trustworthiness of a popular research design. We address these questions by simulating conflict events based on spatial covariates from seven high-profile conflicts. We find that standard designs fail to deliver reliable inference even under ideal conditions at alarming rates. We also test a set of statistical remedies which strongly improve the results: Controlling for the geographic area of spatial units eliminates an important source of spurious correlation. In time-series analyses, the same result can be achieved with unit-level fixed effects. Under outcome diffusion, spatial lag models with area controls produce most reliable inference. When those are computationally intractable, geographically larger aggregations lead to similar improvements. Generally, all analyses should be performed at two separate levels of geographic aggregation. To facilitate future research into geographic methods, we release the Simple Conflict Event Generator (SCEG) developed for this analysis.
Analysis of risk factors of rapid attenuation of graft endothelium in the early stage after penetrating keratoplasty
Authors: Xu Ting-ting , Cao Rui , Dong Yan-ling , Xie Li-xin , Cheng Jun
Published: April 2022

This study aimed to analyze the factors of rapid attenuation of graft endothelium in the early stage after penetrating keratoplasty (PKP), with a view to guiding patients with PKP to better long-term outcomes. This study included 226 patients who underwent PKP with follow-up time >1 year at the Qingdao Eye Hospital of Shandong First Medical University from January 2018 to June 2020. Medical records were retrospectively studied, and donor factors, patient factors, and surgical factors were comparatively analyzed to clarify those affecting the rapid decay of graft endothelium after PKP. The median time between excision and death >60 min and patient age >60 years were risk factors for endothelial cell loss (ECL) rate >30% at 1 month postoperatively. However, a higher percentage of patients with donor age ≤60 years and Optisol preservation solution had endothelial cell density (ECD) >2000 cells/mm2 in the graft at postoperative 1 year. A year after the surgery, patients with corneal endothelial decompensation and immune rejection were at risk for ECD < 1000 cells/mm2. The combined operations had a significant effect on the ECL in the early postoperative period. Patients who underwent combined extracapsular cataract extraction or intraocular lens implantation had a significantly higher rate of ECL at postoperative 1 month than other patients, and no significant effect at postoperative 1 year. However, patients without combined operations have a higher probability of maintaining a high level of graft ECD. The graft diameter also affected postoperative ECL. In patients with a larger graft diameter, attenuation of ECD was slower. The ultimate goal of PKP is to maintain graft transparency for extended periods. The use of younger donors, minimizing unnecessary operation in the anterior chamber, and minimizing immune rejection may maintain a greater donor corneal endothelium in the long term.
Characterisation of the long-term physical and mental health consequences of SARS-CoV-2 infection: A systematic review and meta-analysis protocol
Authors: Kuodi Paul , Gorelik Yanay , Edelstein Michael
Published: April 2022

Background

As of July 2021, there has been more than 185 million documented cases of the novel coronavirus (SARS-CoV-2) infections and more than 4 million deaths globally. Despite more than 90% of documented cases being classified as “recovered” from SARS-CoV-2 infection, a proportion of patients reported a wide variety of persisting symptoms after the initial onset or acute phase of the infection, often referred to as “Long Covid”. As data on the symptomatology of post-acute SARS-CoV-2 infection gradually becomes available, there is an urgent need to organise and synthesise the data in order to define what constitutes Long Covid and assist with its management in clinical and community settings.

Methods

This protocol follows the Preferred Reporting Items for Systematic Review and Meta-analysis Protocols (PRISMA-P) guidelines. A comprehensive literature search strategy will be developed in accordance with the Cochrane highly sensitive search guidelines. The following electronic databases will be searched for studies to include in the systematic review and meta-analysis: MEDLINE (via PubMed), Scopus, Google Scholar, Web of Science (Web of Knowledge), Science direct, EMBASE, Mednar, Psych INFO, and EBSCOhost. Dual screening will be applied at every screening stage. Two reviewers will independently screen titles, abstracts and full text of potentially eligible studies following the predefined inclusion and exclusion criteria in order to select studies to include in the review. As heterogeneity is anticipated between the included studies, data will be pooled in a meta-analysis using a random effects model. A clustering analytic approach will be applied to identify symptoms groupings and assign the symptoms into clusters. R statistical software will be used for the meta-analysis. Highly heterogenous data will be synthesised narratively. The studies will be assessed, for quality using quality assessment tools appropriate for each study design. Two reviewers will independently undertake the quality of studies assessments.

Dissemination plans

Findings of the systematic review will be disseminated through a peer-reviewed publication and presentation of findings at conferences, workshops and government and private sector stakeholder engagement meetings.

Clinical trial registration

PROSPERO registration number: CRD4202126589. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD4202126589.
Mass email risk communication: Lessons learned from COVID-19-triggered campus-wide evictions in Canada and the United States
Authors: Wu Haorui
Published: April 2022

From an out-of-province/state and international post-secondary student perspective, this article (a) explores mass email risk communication facilitation during the COVID-19-triggered campus-wide evictions in Canada and the United States; and (b) develops relative recommendations to improve mass email risk communication strategies for future emergency response. Investigating mass email risk communication-related impacts on students in a tertiary educational context has revealed a significant deficit in emergency response research, practice, and policymaking. Mandatory temporary university and college closures during the COVID-19 first wave provided an opportunity to address this research and practice deficit, as most Canadian and American universities/colleges administered their eviction communication via daily mass email chains. Through a phenomenological lens, this study interviewed twenty out-of-province/state and international students, ten from each country respectively, to examine student eviction experiences associated with intensive mass email risk communication. This research identified four factors linked to mass email risk communication: email chain characteristics, student interpretation, interdepartmental cooperation, and frontline voices. Synthesizing these findings, four evidence-based recommendations were developed: to efficiently convey risk information to students, to understand student perceptions and to inform their behaviors, to enhance interdepartmental cooperation, and to enable mutual dialogue in decision making. These recommendations could assist post-secondary institutions, and other organizations, in strengthening their mass email risk communication strategies and advancing organizational emergency response plans for future extreme events.
A novel network based linear model for prioritization of synergistic drug combinations
Authors: Li Jiaqi , Xu Hongyan , McIndoe Richard A.
Published: April 2022

Drug combination therapies can improve drug efficacy, reduce drug dosage, and overcome drug resistance in cancer treatments. Current research strategies to determine which drug combinations have a synergistic effect rely mainly on clinical or empirical experience and screening predefined pools of drugs. Given the number of possible drug combinations, the speed, and scope to find new drug combinations are very limited using these methods. Due to the exponential growth in the number of drug combinations, it is difficult to test all possible combinations in the lab. There are several large-scale public genomic and phenotypic resources that provide data from single drug-treated cells as well as data from small molecule treated cells. These databases provide a wealth of information regarding cellular responses to drugs and offer an opportunity to overcome the limitations of the current methods. Developing a new advanced data processing and analysis strategy is imperative and a computational prediction algorithm is highly desirable. In this paper, we developed a computational algorithm for the enrichment of synergistic drug combinations using gene regulatory network knowledge and an operational module unit (OMU) system which we generate from single drug genomic and phenotypic data. As a proof of principle, we applied the pipeline to a group of anticancer drugs and demonstrate how the algorithm could help researchers efficiently find possible synergistic drug combinations using single drug data to evaluate all possible drug pairs.
Opioid-related overdose and chronic use following an initial prescription of hydrocodone versus oxycodone
Authors: Weiner Scott G. , Hendricks Michelle A. , El Ibrahimi Sanae , Ritter Grant A. , Hallvik Sara E. , Hildebran Christi , Weiss Roger D. , Boyer Edward W. , Flores Diana P. , Nelson Lewis S. , Kreiner Peter W. , Fischer Michael A.
Published: April 2022

Background

Hydrocodone and oxycodone are prescribed commonly to treat pain. However, differences in risk of opioid-related adverse outcomes after an initial prescription are unknown.

This study aims to determine the risk of opioid-related adverse events, defined as either chronic use or opioid overdose, following a first prescription of hydrocodone or oxycodone to opioid naïve patients.

Methods

A retrospective analysis of multiple linked public health datasets in the state of Oregon. Adult patients ages 18 and older who a) received an initial prescription for oxycodone or hydrocodone between 2015–2017 and b) had no opioid prescriptions or opioid-related hospitalizations or emergency department visits in the year preceding the prescription were followed through the end of 2018. First-year chronic opioid use was defined as ≥6 opioid prescriptions (including index) and average ≤30 days uncovered between prescriptions. Fatal or non-fatal opioid overdose was indicated from insurance claims, hospital discharge data or vital records.

Results

After index prescription, 2.8% (n = 14,458) of individuals developed chronic use and 0.3% (n = 1,480) experienced overdose. After adjustment for patient and index prescription characteristics, patients receiving oxycodone had lower odds of developing chronic use relative to patients receiving hydrocodone (adjusted odds ratio = 0.95, 95% confidence interval (CI) 0.91–1.00) but a higher risk of overdose (adjusted hazard ratio (aHR) = 1.65, 95% CI 1.45–1.87). Oxycodone monotherapy appears to greatly increase the hazard of opioid overdose (aHR 2.18, 95% CI 1.86–2.57) compared with hydrocodone with acetaminophen. Oxycodone combined with acetaminophen also shows a significant increase (aHR 1.26, 95% CI 1.06–1.50), but not to the same extent.

Conclusions

Among previously opioid-naïve patients, the risk of developing chronic use was slightly higher with hydrocodone, whereas the risk of overdose was higher after oxycodone, in combination with acetaminophen or monotherapy. With a goal of reducing overdose-related deaths, hydrocodone may be the favorable agent.
A portrait of the urban female: Sebastián Lelio’s Gloria and Gloria Bell
Authors: Vilches Patricia
Published: April 2022

The COVID-19 pandemic caused us to mourn the loss of an intimate relationship with the city and with the individuals who inhabit that space. Through Gloria (2013) and the faithful English-language remake Gloria Bell (2018), Chilean director Sebastián Lelio illustrates how such urban interconnection might have been tenuous all along. In Spanish (Gloria Cumplido, interpreted by Paulina García) and in English (Gloria Bell, played by Julianne Moore), we witness a protagonist seeking purchase in Santiago and Los Angeles respectively. This article examines how Gloria copes with the alienating space of the city and her feelings of abandonment and loneliness through soundscapes (in the disco, her car, her flat, etc.), dancing and wardrobe (which she uses to perform). Among her many afflictions, the protagonist suffers the pain of distance imposed by her grown children and the fall out of a failed new love, one that has recently blossomed and into which she had placed all her hopes. Together, these shatter Gloria’s everyday routine while channelling and honouring a deeper personal passion.
The right to rights and Central American/Mexican migration films: Reading Sin nombre (Fukunaga 2009) and La jaula de oro/The Golden Dream (Quemada-Díez 2013) with political theory
Authors: Shaw Deborah
Published: April 2022

In this article, I argue in favour of using political and social theory as a framework for reading Central American and Mexican migration films, using Sin nombre (Fukunaga 2009) and La jaula de oro/The Golden Dream (Quemada-Díez 2013) as case studies. Key ideas of Hannah Arendt, Giorgio Agamben, Zygmunt Bauman and Judith Butler can yield important insights when applied to the readings of migration films. My particular interest here is their conceptualizations of the scale of value applied to human life, and the resulting right to rights, or failure to be granted rights, as this is particularly apposite to the condition of migrants and refugees and to the role of film in creating value. A central argument is that film has a specific role in challenging or endorsing the negative values placed on the lives of migrant/refugees in hegemonic political and media discourses. I claim that cinema has the ability to create Arendtian personae, particularly important as in the political and media discourses around refugees and migrants the embodied experiences of refugee–migrants themselves are frequently absent. La jaula de oro presents a textual and extra-textual call for the right to rights for its non-citizen migrant characters. Yet, film also has the potential to support prevailing fears and stereotypes, and work against Arendt’s concept of the right to rights, and I argue that Sin nombre runs the risk of endorsing this position.
Decolonizing Canadian Water Policy
Authors: McKibbin Corey
Published: April 2022

Meaningful lessons about decolonizing water infrastructure (social, economic and political) can be learned if we scrutinize existing governance principles such as the ones provided by the
Organization for Economic Cooperation and Development (OECD)
Principles on Water Governance (OECD, 2021). Instead of using
only Western frameworks to think about policy within Indigenous spheres of water, sanitation and hygiene (WaSH), the Government of Canada can look to Indigenous ways of knowing to compliment their understanding of how to govern areas of WaSH efficiently. In this paper, the term
Indigenous encompasses First Nations, Inuit and Métis populations (Hanrahan & Hudson, 2014; Blaser, 2012). I present this paper as
a step out of many toward decolonizing water governance in Canada. I hope to have shown in this paper that it is necessary to make space for other voices in water governance. By highlighting the dangers in the Case Studies, three lessons are apparent in this paper: 1. There needs to be an addition of Indigenous Two-Eyed Seeing in water governance; 2. Canada must strengthen its nation-to-nation praxis with Indigenous communities; and 3. There needs to be a creation of space in WaSH that fosters Indigenous voices. This is necessary such that there can be equal participation in policy conversations to mitigate existing problems and explore new possibilities.
Growth and productivity of ágata potato cultivar under different doses of organomineral fertilizer
Authors: Dias da Silva Renan César , Francis Cardoso Atalita , Lima Luara Cristina de , Magno de Queiroz Luz José , Maria Quintão Lana Regina , De Camargo Reginaldo
Published: April 2022

Potato is a plant that has high nutrient demand during its cycle. Given the concern with the environment, due to the large amount of synthetic mineral fertilizer used in the crops, the objective of this work was to evaluate the efficiency of organomineral fertilizers in the cultivation of potato, cultivar Ágata, under cerrado conditions. The experimental design was in subdivided plots, consisted of four doses of organomineral fertilizer, corresponding to 40, 60, 80, 100 and 120% of the mineral fertilizer dose in the organomineral source (2800 kg ha-1 of formulated 3-32-6) and the subplots consisted of four collection seasons (61, 74, 89 and 110 days after planting) and four repetitions. Organomineral fertilizer with 40% of the recommended dose for potato cultivation provides higher yield of tubers in the Especial potato class and higher accumulation of total dry mass, in addition to providing satisfactory productivity for the tubers of higher commercial value. The use of organomineral fertilizers promotes the same behavior as mineral fertilizers, not interfering with potato development.