bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rotaxane rings promote oblique packing and extended lifetimes in DNA-templated molecular dye aggregates
Authors: Barclay Matthew S. , Roy Simon K. , Huff Jonathan S. , Mass Olga A. , Turner Daniel B. , Wilson Christopher K. , Kellis Donald L. , Terpetschnig Ewald A. , Lee Jeunghoon , Davis Paul H. , Yurke Bernard , Knowlton William B. , Pensack Ryan D. 
Published: February 2021

AbstractMolecular excitons play a central role in natural and artificial light harvesting, organic electronics, and nanoscale computing. The structure and dynamics of molecular excitons, critical to each application, are sensitively governed by molecular packing. Deoxyribonucleic acid (DNA) templating is a powerful approach that enables controlled aggregation via sub-nanometer positioning of molecular dyes. However, finer sub-Angstrom control of dye packing is needed to tailor excitonic properties for specific applications. Here, we show that adding rotaxane rings to squaraine dyes templated with DNA promotes an elusive oblique packing arrangement with highly desirable optical properties. Specifically, dimers of these squaraine:rotaxanes exhibit an absorption spectrum with near-equal intensity excitonically split absorption bands. Theoretical analysis indicates that the transitions are mostly electronic in nature and only have similar intensities over a narrow range of packing angles. Compared with squaraine dimers, squaraine:rotaxane dimers also exhibit extended excited-state lifetimes and less structural heterogeneity. The approach proposed here may be generally useful for optimizing excitonic materials for a variety of applications ranging from solar energy conversion to quantum information science.
Fossilized anaerobic and possibly methanogenesis-fueling fungi identified deep within the Siljan impact structure, Sweden
Authors: Drake Henrik , Ivarsson Magnus , Heim Christine , Snoeyenbos-West Oona , Bengtson Stefan , Belivanova Veneta , Whitehouse Martin 
Published: February 2021

AbstractRecent discoveries of extant and fossilized communities indicate that eukaryotes, including fungi, inhabit energy-poor and anoxic environments deep within the fractured igneous crust. This subterranean biosphere may constitute the largest fungal habitat on our planet, but knowledge of abyssal fungi and their syntrophic interactions with prokaryotes and their concomitant metabolisms is scarce. Here we report findings of fossilized, chitin-bearing fungal hyphae at ~540 m depth in fractured bedrock of the Siljan impact structure, the largest crater in Europe. Strong 13C-enrichment of calcite precipitated with and on the fungi suggests formation following methanogenesis, and that the anaerobic fungi decomposed dispersed organic matter producing for example H2 that may have fueled autotrophic methanogens. An Eocene age determined for the calcite infers the first timing constraint of fossilized fungi in the continental igneous crust. Fungi may be widespread decomposers of organic matter and overlooked providers of H2 to autotrophs in the vast rock-hosted deep biosphere.
How accurate are citations of frequently cited papers in biomedical literature?
Authors: Pavlovic Vedrana , Weissgerber Tracey , Stanisavljevic Dejana , Pekmezovic Tatjana , Milicevic Ognjen , Lazovic Jelena Milin , Cirkovic Andja , Savic Marko , Rajovic Nina , Piperac Pavle , Djuric Nemanja , Madzarevic Petar , Dimitrijevic Ana , Randjelovic Simona , Nestorovic Emilija , Akinyombo Remi , Pavlovic Andrija , Ghamrawi Ranine , Garovic Vesna , Milic Natasa 
Published: February 2021

Abstract
Citations are an important, but often overlooked, part of every scientific paper. They allow the reader to trace the flow of evidence, serving as a gateway to relevant literature. Most scientists are aware of citations’ errors, but few appreciate the prevalence of these problems. The purpose of the present study was to examine how often frequently cited papers in biomedical scientific literature are cited inaccurately. The study included an active participation of the first authors of included papers; to first-hand verify the citations accuracy. Findings from feasibility study, where we reviewed 1540 articles containing 2526 citations of 14 most cited articles in which the authors were affiliated with the Faculty of Medicine University of Belgrade, were further evaluated for external confirmation in an independent verification set of articles. Verification set included 4912 citations identified in 2995 articles that cited 13 most cited articles published by authors affiliated with the Mayo Clinic Division of Nephrology and Hypertension. A citation was defined as being accurate if the cited article supported or was in accordance with the statement by citing authors. At least one inaccurate citation was found in 11 and 15% of articles in the feasibility study and verification set, respectively, suggesting that inaccurate citations are common in biomedical literature. The most common problem was the citation of nonexistent findings (38.4%), followed by an incorrect interpretation of findings (15.4%). One-fifth of inaccurate citations were due to chains of inaccurate citations. Based on these findings, several actions to reduce citation inaccuracies have been proposed.
Machine learning‐based scheduling: a bibliometric perspective
Authors: Li Shiyun , Yu Tianzong , Cao Xu , Pei Zhi , Yi Wenchao , Chen Yong , Lv Ruifeng 
Published: February 2021

AbstractIn recent years, the rapid development of artificial intelligence and data science has given rise to the study of data driven algorithms in highly volatile systems. The scheduling of complex shop floor resources falls into such a category, which is often non‐linear in nature, time varying, multi‐objective, and subject to interruptions. Ergo, the machine learning‐based scheduling, has become a research hotspot and attracted the attention of many scholars. In the literature, the research methods employed in solving scheduling problems are based on various perspectives, such as mathematical programming, combinatorial optimization, and heuristic rules. However, due to the inherent complexity of the problem, many issues remain to be addressed. In particular, with the availability of production data, the progress of computing power, and the breakthrough in intelligent algorithms, a novel branch of data driven algorithms present great potential, for example, the deep learning and reinforcement learning‐based algorithms. To reveal the value of machine learning‐based scheduling methods, bibliometric analysis was conducted to analyse the relevant articles and documents from the year 1980 to 2019. Finally, the future research trend in the domain of machine learning‐based scheduling is considered and tips are provided for researchers as well as practitioners to find leading scientists for collaborations.
Comparative study of stator consequent‐pole permanent magnet machines
Authors: Li Ya , Yang Hui , Lin Heyun 
Published: February 2021

AbstractA comparative investigation is made of stator consequent‐pole (SCP) machines with different permanent magnet (PM) arrangements. Compared with conventional surface‐mounted PM (SPM) configurations, SCP configurations produce more orders of air‐gap field harmonics. Due to asymmetrical PM magnetomotive force (MMF) distributions and the double‐side slotting effect, SCP machines exhibit multiple air‐gap field harmonics, especially relatively enhanced low‐order field harmonics, for torque production. As a consequence, improved torque capability can be obtained over that of conventional SPM counterparts. Machine topologies and operating principles are described. The design parameters of four SCP machines with different magnet arrangements are globally optimised. The key electromagnetic performances, including open‐circuit performance, torque quality, field‐weakening capability, and efficiency, are comprehensively investigated and compared by the finite element (FE) method. Finally, some experimental measurements on an optimally selected SCP machine prototype are carried out to validate the theoretical and FE analyses.
HU‐PageScan: a fully convolutional neural network for document page crop
Authors: das Neves Ricardo Batista , Lima Estanislau , Bezerra Byron L.D. , Zanchettin Cleber , Toselli Alejandro H. 
Published: February 2021

November The offer of online, automated, and impersonal services demand users to upload scanned copies of their documents to the organisations. As a consequence of this decentralisation, the documents present more challenges to the already complex process of image processing and information extraction. To address this problem, the authors presented an optimised fully convolutional neural network model for document segmentation that works on mobile devices to detect the region of the document in the captured image. They performed experiments in three representative datasets comparing the proposed method with the Geodesic object Proposals, U‐net, Mask R‐CNN, and OctHU‐PageScan algorithms. They also compared the proposed model with all competitors of the ICDAR2015 Competition on smartphone document capture. Furthermore, they performed a qualitative and comparative analysis with the CamScanner software, a popular app for Android and iOS smartphones used for more than 100 million users in over 200 countries. The proposed approach achieved a significant performance compared with the current state‐of‐the‐art methods, providing a powerful approach for document segmentation in photos and scanned images.
Direct synthesis and systematic design of a multi‐objective controller for grid‐connected inverters under weak grid conditions
Authors: Raja Parthiban , Bhaskaran Umamaheswari , Shanmugam Paramasivam 
Published: February 2021

A systematic approach for synthesis and tuning of the controller for grid‐connected inverters with LCL‐filter is proposed in this study. The design objectives like current tracking, harmonics rejection, resonant damping and extended stability over wide grid variations are addressed. Controller structure is synthesised by direct synthesis approach which leads to a systematic design procedure and tuning method. Low‐frequency approximation of the system under worst grid condition is used for the synthesis of the current controller and the resonance component is handled separately. Tunable parameters are identified to investigate grid variations in the process of augmenting the synthesised controller for realisability. Complete design, stability analysis and tuning are dealt with directly in the discrete domain. Detailed simulation and experimental validation are carried out on a 1 kW prototype inverter. The method proposed in this study serves as a simplified design tool for effective design of a multi‐objective controller for grid‐connected inverters.
Feature pyramid U‐Net for retinal vessel segmentation
Authors: Liu Yi‐Peng , Rui Xue , Li Zhanqing , Zeng Dongxu , Li Jing , Chen Peng , Liang Ronghua 
Published: February 2021

AbstractThe retinal vessel is the only microvascular network that can be directly and non‐invasively observed in humans. Cardiovascular and cerebrovascular diseases, such as diabetes, hypertension, can lead to structural changes of the retinal microvascular network. Therefore, it is of great significance to study effective retinal vessel segmentation methods and assist doctors in early diagnoses with quantitative results for vascular networks. In this study, we propose a novel convolutional neural network named feature pyramid U‐Net (FPU‐Net) that extracts multiscale representations by constructing two feature pyramids both on the encoder and the decoder of U‐Net. In this representation, objects features with different size like micro‐vessels and pathology will be fused for better vessel segmentation. The experimental results show that compared with state‐of‐the‐art methods, FPU‐Net is superior in terms of accuracy, sensitivity, F1‐score, and area under the curve and capable of stronger domain generalisation across different datasets.
Low‐profile millimetre‐wave wideband microstrip antenna with parasitic patch arrays
Authors: Xue Mei , Wan Weikang , Wang Qidong , Cao Liqiang 
Published: February 2021

AbstractA millimetre‐wave low‐profile wideband microstrip antenna is proposed. To widen impedance bandwidth and achieve stable large gain simultaneously, coplanar parasitic patch arrays are arranged on both sides of a microstrip patch fed by a coaxial probe. Double slots are etched on the microstrip patch to reduce H‐plane cross‐polarization levels. Zero‐phase‐reflection analysis with Floquet‐port model is proposed to predict resonant frequency of the parasitic patch arrays. Resonance modes excited is verified according to input impedance with an ideal probe. Two adjacent broadside resonances respectively dominated by the quasi‐TM10 mode of the microstrip patch and quasi‐TM30 of the parasitic patch array are excited in turn. The proposed antenna with a dimension of 1.06 × 1.06 × 0.024 λ03 (λ0 is the wavelength of 29 GHz in free space) realizes 15% (27–31.35 GHz) impedance bandwidth for |S11| ≤ −10 dB. Realized peak gain is up to 9.26 dBi and 2‐dB gain bandwidth is 15.7%. H‐plane cross‐polarization levels within 3‐dB beamwidth are less than −14 dB, and back radiation levels are less than −17.9 dB.
3D imaging of moving targets for ultra‐wideband MIMO through‐wall radar system
Authors: Pan Jun , Ye Shengbo , Shi Cheng , Yan Kun , Liu Xin , Ni Zhikang , Yang Guangyao , Fang Guangyou 
Published: February 2021

AbstractUltra‐wideband (UWB) radar is widely used in static through‐wall imaging (TWI). There are still many imaging problems of motion through‐wall targets for complex system structure and unknown wall environment. Herein, a motion compensation method based on the reference channel and a modified Kirchhoff migration imaging algorithm are proposed for Ultra‐wideband (UWB) MIMO sparse array, which is used for high‐precision 3D TWI of moving targets. The channels of the MIMO radar are time‐division multiplexing based on microwave switch. Besides, a reference channel is added for motion compensation of moving targets. Performing motion compensation on the target before 3D imaging can effectively avoid the problems of defocus and position deviation caused by target motion. In the proposed imaging method, the backward Green function is used to replace the forward Green function to solve the problem of a large field of view with small arrays. The experiment with a static through‐wall target proves that the proposed imaging algorithm can suppress sidelobes well compared with the traditional back‐projection algorithm (BPA). Through‐wall experiments are carried out for targets with different speeds, and results show that the positioning accuracy and sidelobe level of the proposed compensation method is better than previously proposed methods.
Herpes Simplex Virus Keratitis in a University Tertiary Referral Centre – Clinical Features and Surgical Approaches
Authors: Alfaro Rangel Raul , Lepper Sabine , Szentmáry Nóra , Langenbucher Achim , Seitz Berthold 
Published: February 2021

Abstract
Purpose To assess prevalence, clinical manifestations, required keratoplasties, follow-up, and outcome in patients with Herpes Simplex Virus Keratitis (HSK) attending a University Tertiary Referral Center.
Design Retrospective (12 years), descriptive, observational study.
Methods A total of 817 eyes with clinical diagnosis of HSK from 779 patients were classified by the type of presentation. We gathered data on the visual acuity, refraction, IOP, and required surgical procedures.
Results Stromal involvement including scars represented the most common diagnosis in our department and the main indication of penetrating keratoplasty (PKP). Epithelial keratitis (16%) presented with the best visual acuity at the first visit. Necrotizing keratitis represented 17% of the patients, 78% of whom required PKP; this group also had the worst visual acuity at first examination and was the main indication for emergency PKP. Among all eyes, 288 (35%) required PKP. A total of 230 (28%) PKPs were elective procedures and 58 (7%) PKPs were performed as emergency procedures. Two patients with quiet endothelial decompensations after recurrent HSV endotheliitis were treated with DMEK and had good visual outcomes without HSV recurrence at last follow-up.
Conclusions HSK is a prevalent disease with severe consequences when not treated appropriately and on time. Even when making an accurate diagnosis, the disease can be extremely aggressive, with all the implications it brings to the patients and health system. Elective PKP had better outcomes in terms of visual acuity and clear graft percentage compared to emergency PKP.
Comparative Surface Imaging Study of Multifocal Diffractive Intraocular Lenses
Authors: Son Hyeck Soo , Lee Jung Min , Khoramnia Ramin , Choi Chul Young 
Published: February 2021

Abstract
Purpose To analyse and compare the surface topography and roughness of three different types of diffractive multifocal IOLs.
Methods Using scanning electron microscope (SEM, Inspect F, 5.0 KV, maximum magnification up to 20,000) and atomic force microscope (AFM, Park Systems, XE-100, non-contact, area profile comparison, 10 × 10 µm, 40 × 40 µm), the surface quality of the following diffractive IOLs was studied: the AcrySof IQ PanOptix (Alcon, USA), the AT LARA 829MP (Carl Zeiss Meditec, Germany), and Tecnis Symfony (Johnson&Johnson Vision, USA). The measurements were made over three representative areas (central non-diffractive optic, central diffractive optic, and diffractive step) of each IOL. Roughness profile in terms of mean arithmetic roughness (Ra) and root-mean-squared roughness (Rq) values were obtained and compared statistically.
Results In SEM examination, all IOLs showed a smooth optical surface without any irregularities at low magnification. At higher magnification, Tecnis Symfony showed unique highly regular, concentric, and lineate structures in the diffractive optic area which could not be seen in the other studied diffractive IOLs. The differences in the measured Ra and Rq values of the Tecnis Symfony were statistically significant compared to the other models (p < 0.05).
Conclusion Various different topographical traits were observed in three diffractive multifocal IOLs. The Ra values of all studied IOLs were within an acceptable range. Tecnis Symfony showed statistically significant higher surface Ra values at both central diffractive optic and diffractive step areas. Furthermore, compared to its counterparts, Tecnis Symfony demonstrated highly ordered, concentric pattern in its diffractive surfaces.
Intraluminal gas escape from biopsy valves and endoscopic devices during endoscopy: caution advised during the COVID-19 era
Authors: Urakawa Shinya , Hirashita Teijiro , Momose Kota , Nishimura Makoto , Nakajima Kiyokazu , Milsom Jeffrey W. 
Published: February 2021

Abstract
Background and study aims The risk of aerosolization of body fluids during endoscopic procedures should be evaluated during the COVID-19 era, as this may contribute to serious disease transmission. Here, we aimed to investigate if use of endoscopic tools during flexible endoscopy may permit gas leakage from the scope or tools.
Material and methods Using a fresh 35-cm porcine rectal segment, a colonoscope tip, and manometer were placed intraluminally at opposite ends of the segment. The colonoscope handle, including the biopsy valve, was submerged in a water bath. Sequentially, various endoscopic devices (forceps, clips, snares, endoscopic submucosal dissection (ESD) knives) were inserted into the biopsy valve, simultaneously submerging the device handle in a water bath. The bowel was slowly inflated up to 74.7 mmHg (40 inH2O) and presence of gas leakage, leak pressure, and gas leakage volume were measured.
Results Gas leakage was observed from the biopsy valve upon insertion and removal of all endoscopic device tips with jaws, even at 0 mmHg (60/60 trials). The insertion angle of the tool affected extent of gas leakage. In addition, gas leakage was observed from the device handles (8 of 10 devices) with continuous gas leakage at low pressures, especially two snares at 0 mmHg, and an injectable ESD knife at 0.7 ± 0.8 mmHg).
Conclusions Gas leakage from the biopsy valve and device handles commonly occur during endoscopic procedures. We recommend protective measures be considered during use of any tools during endoscopy.
Impact of simple, specific, verbal instructions on the quality of bowel preparation in hospitalized patients undergoing colonoscopy: a multicenter randomized controlled trial
Authors: Triantafyllou Konstantinos , Gkolfakis Paraskevas , Skamnelos Alexandros , Diamantopoulou Georgia , Dagas Athanasios , Tziatzios Georgios , Thomopoulos Konstantinos , Potamianos Spyros , Christodoulou Dimitrios 
Published: February 2021

AbstractBackground and study aims Bowel preparation for colonoscopy is frequently inadequate in hospitalized patients. We explored the impact of specific verbal instructions on the quality of inpatients bowel preparation and factors associated with preparation failure.Patients and methods Randomized (1:1), two strata (mobilized vs. bedridden; 3:2) trial of consecutive inpatients from four tertiary centers, who received either specific, verbal instructions or the standard of care (SOC) ward instructions about bowel preparation. The rate of adequate bowel preparation (Boston Bowel Preparation Score [BBPS] ≥ 6, no segment < 2) comprised the primary endpoint. Mean BBPS score, good (BBPS score ≥ 7, no segment score < 2) and excellent (BBPS = 9) were among secondary endpoints.Results We randomized 300 inpatients (180 mobile) aged 71.7 ± 15.1 years in the intervention (49.7 %) and SOC (50.3 %) groups, respectively. Overall, more patients in the intervention group achieved adequate bowel preparation, but this difference did not reach statistical significance neither in the intention-to-treat [90/149 (60.4 %) vs. 82/151 (54.3 %); P = 0.29] nor in the per-protocol analysis [90/129 (69.8 %) vs. 82/132 (62.1 %); P = 0.19]. Overall BBPS score did not differ statistical significantly in the two groups, but the provision of specific verbal instructions was associated with significant higher rates of good (58.1 % vs. 43.2 %; P = 0.02) and excellent (31.8 % vs. 16.7 %; P = 0.004) bowel preparation compared to the SOC group. Administration of same-day bowel preparation and patient American Society of Anesthesiologists score > 2 were identified as risk factors for inadequate bowel preparation.Conclusions Provision of specific verbal instructions did not increase the rate of adequate bowel preparation in a population of mobilized and bedridden hospitalized patients.