bluuebunny/crossref_metadata_2025 huggingface dataset:
A new panchromatic classification of unclassified Burst Alert Telescope active galactic nuclei
Authors: Giuliani L. , Ghisellini G. , Sbarrato T.
Published: February 2021

We collect data at all frequencies for the new sources classified as unknown active galactic nuclei (AGNs) in the latest Burst Alert Telescope all-sky hard X-ray catalog. Focusing on the 36 sources with measured redshift, we compute their spectral energy distribution (SED) from radio to γ-rays with the aim to classify these objects. We apply emission models that attempt to reproduce the obtained SEDs, including: (i) a standard thin accretion disk together with an obscuring torus and a X-ray corona; (ii) a two temperature thick advection-dominated flow; (iii) an obscured AGN model, accounting for absorption along the line of sight at kiloelectronvolt energies and in the optical band; and (iv) a phenomenological model to describe the jet emission in blazar-like objects. We integrate the models with the SWIRE template libraries to account for the emission of the host galaxy. For every source we found a good agreement between data and our model. Considering that the sources were selected in the hard X-ray band, which is rather unaffected by absorption, we expected and found a large fraction of absorbed radio-quiet AGNs (31 out of 36) and some additional rare radio-loud sources (5 out of 36), since the jet emission in hard X-rays is important for aligned jets owing to the boost produced by the beaming effect. With our work we can confirm the hypothesis that a number of galaxies, whose optical spectra lack AGN emission features, host an obscured active nucleus. The approach we used proved to be efficient in rapidly identifying objects, which commonly used methods were not able to classify.
Rotational spectroscopic study and astronomical search for propiolamide in Sgr B2(N)
Authors: Alonso E. R. , Kolesniková L. , Belloche A. , Mata S. , Garrod R. T. , Jabri A. , León I. , Guillemin J.-C. , Müller H. S. P. , Menten K. M. , Alonso J. L.
Published: February 2021

Context. For all the amides detected in the interstellar medium (ISM), the corresponding nitriles or isonitriles have also been detected in the ISM, some of which have relatively high abundances. Among the abundant nitriles for which the corresponding amide has not yet been detected is cyanoacetylene (HCCCN), whose amide counterpart is propiolamide (HCCC(O)NH2).

Aims. With the aim of supporting searches for this amide in the ISM, we provide a complete rotational study of propiolamide from 6 to 440 GHz.

Methods. Time-domain Fourier transform microwave spectroscopy under supersonic expansion conditions between 6 and 18 GHz was used to accurately measure and analyze ground-state rotational transitions with resolved hyperfine structure arising from nuclear quadrupole coupling interactions of the 14N nucleus. We combined this technique with the frequency-domain room-temperature millimeter wave and submillimeter wave spectroscopies from 75 to 440 GHz in order to record and assign the rotational spectra in the ground state and in the low-lying excited vibrational states. We used the ReMoCA spectral line survey performed with the Atacama Large Millimeter/submillimeter Array toward the star-forming region Sgr B2(N) to search for propiolamide.

Results. We identified and measured more than 5500 distinct frequency lines of propiolamide in the laboratory. These lines were fitted using an effective semi-rigid rotor Hamiltonian with nuclear quadrupole coupling interactions taken into consideration. We obtained accurate sets of spectroscopic parameters for the ground state and the three low-lying excited vibrational states. We report the nondetection of propiolamide toward the hot cores Sgr B2(N1S) and Sgr B2(N2). We find that propiolamide is at least 50 and 13 times less abundant than acetamide in Sgr B2(N1S) and Sgr B2(N2), respectively, indicating that the abundance difference between both amides is more pronounced by at least a factor of 8 and 2, respectively, than for their corresponding nitriles.

Conclusions. Although propiolamide has yet to be included in astrochemical modeling networks, the observed upper limit to the ratio of propiolamide to acetamide seems consistent with the ratios of related species as determined from past simulations. The comprehensive spectroscopic data presented in this paper will aid future astronomical searches.
Regularizing effect of the interplay between coefficients in Dirichlet problems with convection or drift terms
Authors: Boccardo Lucio
Published: February 2021

There are very important results by Enrique Zuazua on the subject of the convection-diffusion equation

ut−div(a(x)∇u)=−d⋅∇(|u|q−1u), in (0,+∞) × ℝN.

In some sense this paper deals with a linear (i.e. q = 1) elliptic counterpart of the above equation if d is not constant.

We prove regularizing results on the solutions, under assumptions of interplay between the datum and the coefficient of the zero order term or between the modulus of the drift and the coefficient of the zero order term.
Naturalness in the production of vegetable oils and proteins
Authors: Carré Patrick
Published: February 2021

The crushing industry is called upon to modify its processing methods in response to a rising demand for vegetable proteins, while at the same time increasing transparency and naturality. Changing the processes without taking this request into account would mean risking rejection and failure. The social sciences have shown that the collective unconscious inextricably links the notion of naturalness to healthy eating, respect for the environment, and social honesty. However, this notion goes beyond what’s rational and proves difficult to pin down when it comes to evaluating products. France does not recognize the ISO data sheet that defines what a “natural” ingredient is. Yet we do need a standard, if only to make informed choices between different possible technological paths. This standard of reference could be inspired by available norms in related fields, or it could be based on the best available technologies within a framework that takes into account both societal aspirations and the technical and economic possibilities of the industrial world. To achieve this, the sector’s representative bodies, the State, and consumer advocate groups should engage in a collective approach.
Evaluation and investigation: the determinants of central banking efficiency
Authors: Dar Qaiser Farooq , Young-Hyo Ahn , Dar Gulbadin Farooq
Published: February 2021

The stochastic frontier analysis is a comprehensive and accepted approach for analysing efficiency in case of the parametric functional relationship existing between production processes’ inputs with its output. Usually, in the banking industry, the relationship between the user inputs and outputs are non-deterministic. In the present study, an SFA approach is used to estimate the efficiency of top 17 Asian central banks in combining three inputs and one output. Structural equation modelling is applied to examine the impact of the country’s international trade and economic growth on its central bank efficiency. Based on the results, we have observed significant efficiency ranks between the year 2016– 2018. The technical efficiency value estimates by SFA method range from 0.236822 to 0.821864. Our calculations also suggest a positive impact of international trade on central bank efficiency compared to the economic growth of that country.
Eine Alternative zur klassischen Testtheorie? – Eine exemplarische Anwendung der Generalisierbarkeitstheorie auf der Basis von Sekundärdaten
Authors: Sterkele Iris , Pfister Pierrette Baschung , Knols Ruud , de Bruin Eling D
Published: February 2021

Hintergrund Messungen bilden die Grundlage des wissenschaftsbasierten therapeutischen Vorgehens. Messfehler sind jedoch ein verbreitetes Problem. Um Fehlerquellen zu ermitteln, sind erweiterte statistische Modelle notwendig. Im Gegensatz zur klassischen Testtheorie ermöglicht die Generalisierbarkeitstheorie, mehrere Fehlerquellen gleichzeitig zu untersuchen.

Ziel Vergleich der klassischen Testtheorie und der Generalisierbarkeitstheorie anhand eines physiotherapeutischen Beispiels zur Reliabilitätsermittlung und deren Ergebnisse.

Methode Die Messeigenschaft „Reliabilität“ wurde anhand von Daten einer vorangegangenen Reliabilitätsstudie, in der die klassische Testtheorie zum Einsatz kam, untersucht. Dazu wurde exemplarisch eine Generalisierbarkeitsstudie durchgeführt.

Ergebnisse Die Variabilität ging hauptsächlich von den Probanden und der Probanden-Untersucher-Interaktion aus. Unabhängig von fixen oder zufälligen Facetten waren die Generalisierbarkeitskoeffizienten für alle Bedingungen (overall, inter-rater, intra-Messzeitpunkte) exzellent.

Schlussfolgerung Die Ergebnisse deuten darauf hin, dass die Generalisierbarkeitstheorie gegenüber der klassischen Testtheorie Vorteile hat. Diese ermöglicht es, einen wirkungsvollen und effizienten Einsatz von Messinstrumenten im klinischen Alltag zu ermitteln.
Clinical efficacy, timing, and outcomes of ERCP for management of bile duct leaks: a nationwide cohort study
Authors: Desai Aakash , Twohig Patrick , Trujillo Sophie , Dalal Shaman , Kochhar Gursimran S. , Sandhu Dalbir S.
Published: February 2021

Background and study aims Endoscopic retrograde cholangiopancreatography (ERCP) can safely and effectively manage postsurgical or traumatic bile duct leaks (BDLs). Standardized guidelines are lacking regarding effective management of BDLs. Our aim was to evaluate the efficacy, clinical outcomes, and complications of different ERCP techniques and intervention timing using a nationwide database.

Patients and methods We performed a retrospective analysis of the IBM Explorys database (1999–2019), a pooled, national, de-identified clinical database of over 64 million unique patients across the United States. ERCP timing after BDL was classified as emergent (< 1 day), urgent (1–3 days) or expectant (> 3 days). ERCP technique was classified into sphincterotomy, stent or combination therapy. ERCP complications were defined as pancreatitis, duodenal perforation, duodenal hemorrhage, and ascending cholangitis within 7 days of the procedure.

Results Expectant ERCP had a decreased risk of adverse events (AEs) compared to emergent and urgent ERCP (P = 0.004). Rehospitalization rates also were lower in expectant ERCP (P < 0.001). Patients with COPD were more likely to have an AE if the ERCP was performed emergently compared to expectantly (P = 0.002). Combination therapy had a lower rate of ERCP failure compared to placement of a biliary stent (P = 0.02). There was no statistically significant difference in rates of ERCP failure between biliary stent and sphincterotomy (P = 0.06) or sphincterotomy and combination therapy (P = 0.74).

Conclusion Our study suggests that ERCP does not need to be performed emergently or urgently for management of BDLs. Combination therapy is superior to stenting but not sphincterotomy; however, future prospective studies are needed to validate these findings.
EUS-guided placement of fiducial markers for stereotactic body radiation therapy in pancreatic cancer: feasibility, security and a new quality score
Authors: Van Laethem Jean-Luc , Eisendrath Pierre , Figueiredo Mariana , Bouchart Christelle , Moretti Luigi , Mans Laura , Engelholm Jean-Luc , Bali Maria-Antonietta
Published: February 2021

Background and study aims In borderline resectable/locally advanced pancreatic ductal adenocarcinoma (PDAC), stereotactic body radiation therapy (SBRT) is an emerging neoadjuvant treatment option. Endoscopic ultrasound (EUS)-guided insertion of fiducial markers being a prerequisite, our aim was to assess its feasibility and safety and also to evaluate its success, from both the endoscopist’s and radiotherapist’s perspectives.

Patients and methods We prospectively collected data concerning PDAC patients submitted to EUS-guided fiducial placement, from February 2018 to November 2019. Technical success was defined as at least one marker presumed inside the tumor. Quality success was assessed at pre-SBRT computed tomography, accordingly to the number of markers inside or < 1 cm from the tumor, number of markers at the tumor extremity, their location in different planes, the distance between them, and their distance from the biliary stent (if present). A new quality score was then proposed and high-quality success defined as at least six of 12 points.

Results Thirty-seven patients were enrolled. A total of 97 fiducials were implanted, with a median of three fiducials per patient (0–4). The technical success rate was 92 %, with failure of fiducial placement in three patients. Three patients (8 %) had adverse events (fever, mild acute pancreatitis, and biliary stent migration). At pre-SBRT evaluation, two patients’ markers had migrated. The high-quality success rate was 62.5 %.

Conclusions Our results contribute to demonstrating the feasibility and safety of EUS-guided fiducial placement for SBRT treatment in PDAC. It is hoped that the newly proposed quality score will pave the way for improving fiducial positioning and SBRT delivery.
Diagnostic ability of Japan Narrow-Band Imaging Expert Team classification for colorectal lesions by magnifying endoscopy with blue laser imaging versus narrow-band imaging
Authors: Ito Renma , Ikematsu Hiroaki , Murano Tatsuro , Shinmura Kensuke , Kojima Motohiro , Kumahara Kana , Furue Yasuaki , Sunakawa Hironori , Minamide Tatsunori , Sato Daiki , Yamamoto Yoichi , Takashima Kenji , Yoda Yusuke , Hori Keisuke , Yano Tomonori
Published: February 2021

Background and study aims The Japan Narrow-band imaging (NBI) Expert Team (JNET) classification was proposed for evaluating colorectal lesions. However, it remains unknown whether the JNET classification can be applied to magnifying endoscopy with image-enhanced endoscopies other than NBI. This study aimed to compare the diagnostic ability of JNET classification by magnifying endoscopy with blue laser imaging (ME-BLI) and with ME-NBI.

Patients and methods We retrospectively assessed consecutive patients diagnosed per the JNET classification by ME-BLI (BLI group) or ME-NBI (NBI group) between March 2014 and June 2017. We compared the diagnostic value of JNET classification between the groups with one-to-one propensity score matching.

Results Four hundred and seventy-one propensity score-matched pairs of lesions were analyzed. In the BLI and NBI groups, the overall diagnostic accuracies were 92.1 % and 91.7 %, respectively, and those for differentiating between neoplastic and non-neoplastic polyps were 96.6 % and 96.8 %, respectively. The positive predictive value by each JNET classification in BLI vs. NBI group was 90.6 % vs. 96.2 % in Type 1, 94.3 % vs. 94.6 % in Type 2A, 57.7 % vs. 42.3 % in Type 2B, and 100 % vs. 91.7 % in Type 3. The negative predictive value was 97.0 % vs. 96.9 % in Type 1, 88.1 % vs. 82.8 % in Type 2A, 98.0 % vs. 98.2 % in Type 2B, and 98.5 % vs. 98.7 % in Type 3. No statistical difference in the diagnostic results was found between the groups.

Conclusions The diagnostic ability of the JNET classification by ME-BLI and ME-NBI was comparable, with the former also applicable for diagnosis of colorectal lesions.
Amalgamation of cloud-based colonoscopy videos with patient-level metadata to facilitate large-scale machine learning
Authors: Keswani Rajesh N. , Byrd Daniel , Garcia Vicente Florencia , Heller J. Alex , Klug Matthew , Mazumder Nikhilesh R. , Wood Jordan , Yang Anthony D. , Etemadi Mozziyar
Published: February 2021

Background and study aims Storage of full-length endoscopic procedures is becoming increasingly popular. To facilitate large-scale machine learning (ML) focused on clinical outcomes, these videos must be merged with the patient-level data in the electronic health record (EHR). Our aim was to present a method of accurately linking patient-level EHR data with cloud stored colonoscopy videos.

Methods This study was conducted at a single academic medical center. Most procedure videos are automatically uploaded to the cloud server but are identified only by procedure time and procedure room. We developed and then tested an algorithm to match recorded videos with corresponding exams in the EHR based upon procedure time and room and subsequently extract frames of interest.

Results Among 28,611 total colonoscopies performed over the study period, 21,170 colonoscopy videos in 20,420 unique patients (54.2 % male, median age 58) were matched to EHR data. Of 100 randomly sampled videos, appropriate matching was manually confirmed in all. In total, these videos represented 489,721 minutes of colonoscopy performed by 50 endoscopists (median 214 colonoscopies per endoscopist). The most common procedure indications were polyp screening (47.3 %), surveillance (28.9 %) and inflammatory bowel disease (9.4 %). From these videos, we extracted procedure highlights (identified by image capture; mean 8.5 per colonoscopy) and surrounding frames.

Conclusions We report the successful merging of a large database of endoscopy videos stored with limited identifiers to rich patient-level data in a highly accurate manner. This technique facilitates the development of ML algorithms based upon relevant patient outcomes.
Robotisch assistierte Resektion eines zentralen neoadjuvant behandelten Pankreaskarzinoms mit En-bloc-Resektion des Truncus coeliacus (modifizierte Appleby-Operation)
Authors: Thomaschewski Michael , Zimmermann Markus , Honselmann Kim , Müller-Debus Charlotte Friederieke , Jacob Fabian , Wellner Ulrich Friedrich , Keck Tobias , Bausch Dirk
Published: February 2021

Das Pankreaskarzinom im Bereich des Korpus und linksseitig der mesenterikoportalen Achse wird wegen der unspezifischen oder gar fehlenden klinischen Symptome häufig erst in späten Stadien erkannt, wobei in etwa 20% der Fälle bereits eine Infiltration der umliegenden arteriellen oder venösen Gefäße vorliegt. Trotz eines lokal fortgeschrittenen Wachstums (T4, UICC-Stadium III) weisen 30% der Patienten keine Fernmetastasen auf und würden sich potenziell für eine lokale Resektion qualifizieren. Arterielle Resektionen mit Anastomosierung und Gefäßrekonstruktion sind einschränkend mit einer fast 9-fach erhöhten Mortalität des Eingriffs im Vergleich zu Resektionen ohne Gefäßrekonstruktion verbunden. Die Appleby-Operation stellt eine komplexe Operationstechnik dar, die ursprünglich für das fortgeschrittene Magenkarzinom entwickelt wurde. Die Adaptation der Technik wurde für Patienten mit fortgeschrittenen Pankreaskorpus- und Pankreasschwanztumoren mit einer Infiltration des
Truncus coeliacus weiterentwickelt. Der Vorteil der Operation besteht darin, dass technisch keine Rekonstruktion der resezierten Arterien erfolgen muss, da man sich eine natürliche interne Anastomose im Pankreaskopf zwischen der A. mesenterica superior und der A. hepatica über Äste der A. gastroduodenalis zum Erhalt der Leberperfusion und der Magendurchblutung zu Nutze macht. Das Operationsverfahren ist jedoch ebenso mit einer hohen Morbidität und Mortalität verbunden mit vergleichbar schlechten onkologischen Ergebnissen (R0-Raten ca. 60%), sodass das Verfahren bis vor einigen Jahren nicht empfohlen wurde und die Patienten als inoperabel galten. Im Zuge der Entwicklung neoadjuvanter Therapieverfahren beim Pankreaskarzinom wird die Appleby-Operation wieder häufiger durchgeführt, da der Bedarf an lokal radikal resezierenden Operationsverfahren und Techniken im Kontext der multimodalen Behandlung gestiegen ist. Im Zuge der derzeitigen Etablierung der Robotik in der
Viszeralchirurgie könnten bisherige Limitationen der minimalinvasiven Pankreaschirurgie überwunden werden und deutlich mehr Patienten die Vorteile der minimalinvasiven Chirurgie – wie eine schnellere Rekonvaleszenz – ermöglicht werden. Der Einsatz robotischer Operationsverfahren ermöglicht die Erweiterung minimalinvasiver Techniken in den Bereich der komplexen Gefäßresektion und Rekonstruktion. Im vorliegenden Videobeitrag beschreiben wir eine robotisch assistierte modifizierte Appleby-Operation mit dem Einsatz des Da Vinci Xi Surgical System bei einer Patientin mit einem fortgeschrittenen Pankreaskorpuskarzinom nach neoadjuvanter Therapie.
Neuroimaging Findings in Conjunction with Severe COVID-19
Authors: Büttner Laura , Bauknecht Hans Christian , Fleckenstein Florian Nima , Kahn Johannes , Tietze Anna , Bohner Georg , Siebert Eberhard
Published: February 2021

Purpose COVID-19 has a variable, but well-described course. However, some patients additionally present with neurological symptoms. Recent studies also show a broad range of neuroimaging features. The purpose of this study was to perform a snapshot analysis to approximate the frequency and types of neuroimaging findings on CT and MRI scans in a large cohort of SARS-CoV-2-positive patients in a level I COVID-19 center, both in general and in critically ill patients.

Materials and Methods We retrospectively analyzed brain CT and MRI scans of 34 hospitalized COVID-19 patients at our level I COVID-19 center between March 15 and April 24 with regard to pathological neuroimaging findings. In addition, clinical parameters such as neurological symptoms, comorbidities, and type of ventilation therapy were also documented. A descriptive statistical analysis was performed.

Results Pathological findings were detected in 38.2 % of patients in the study cohort. Based on the weekly institutional SARS-CoV-2 report of all positively tested patients in our clinic at the time of data collection, neuroimaging findings could be found in 6 % of all patients (34/565). The most common findings were microbleeds (20.6 %) and signs of hypoxic brain injury (11.8 %). Furthermore, cortical subarachnoid hemorrhage, typical and atypical cerebral hematomas, ischemic strokes, and generalized brain edema were documented. All neuroimaging findings occurred in patients who were either intubated or treated by ECMO.

Conclusion Based on the analysis of this large cohort of SARS-CoV-2-positive patients, pathological neuroimaging findings seem to be relatively rare in general but do occur in a substantial proportion of patients with severe COVID-19 disease needing intubation or ECMO.

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Images Are Data: A Breast Imaging Perspective on a Contemporary Paradigm
Authors: Dietzel Matthias , Clauser Paola , Kapetas Panagiotis , Schulz-Wendtland Rüdiger , Baltzer Pascal Andreas Thomas
Published: February 2021

Background Considering radiological examinations not as mere images, but as a source of data, has become the key paradigm in the diagnostic imaging field. This change of perspective is particularly popular in breast imaging. It allows breast radiologists to apply algorithms derived from computer science, to realize innovative clinical applications, and to refine already established methods. In this context, the terminology “imaging biomarker”, “radiomics”, and “artificial intelligence” are of pivotal importance. These methods promise noninvasive, low-cost (e. g., in comparison to multigene arrays), and workflow-friendly (automated, only one examination, instantaneous results, etc.) delivery of clinically relevant information.

Methods and Results This paper is designed as a narrative review on the previously mentioned paradigm. The focus is on key concepts in breast imaging and important buzzwords are explained. For all areas of breast imaging, exemplary studies and potential clinical use cases are discussed.

Conclusion Considering radiological examination as a source of data may optimize patient management by guiding individualized breast cancer diagnosis and oncologic treatment in the age of precision medicine.

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Isolated Spontaneous Mesenteric Artery Dissection: A Rare Entity
Authors: Pradhan Akshyaya , Bhandari Monika , Vishwakarma Pravesh , Kumar Shailendra , Rai Anurag
Published: February 2021

Isolated spontaneous dissection of the mesenteric artery in the absence of involvement of the aorta or its branches is an uncommon vascular entity. It is generally seen in males and presents with gastrointestinal symptoms due to mesenteric ischemia. However, asymptomatic cases are increasingly being diagnosed due to increased use of computed tomography (CT) angiography. The course is usually self-limiting, and conservative management with bowel rest, strict blood pressure control, anticoagulants, sedatives for pain, and close observation usually suffices. Surgery or endovascular stenting is usually reserved for those exhibiting bowel ischemia or impending rupture. We report a case of a young female with isolated spontaneous mesenteric artery dissection with thrombus, which did not improve with medical therapy and was managed promptly by surgery due to the presence of bowel ischemia.
Clinical Performance of Two Types of Primary Molar Indirect Crowns Fabricated by 3D Printer and CAD/CAM for Rehabilitation of Large Carious Primary Molars
Authors: Al-Halabi Mohammed Nour , Bshara Nada , Nassar Jihad Abou , Comisi John C. , Rizk Charline K.
Published: February 2021

Objectives This randomized clinical trial aimed to evaluate clinical outcomes of two types of esthetic crowns fabricated using a three-dimensional (3D) dental printer and computer-aided design and manufacturing (CAD/CAM) system as an alternative full-coronal restoration for extensively carious pulp-treated primary molars.

Materials and Methods Randomization was done for 50 lower primary molars in 50 child patients, split into two groups based on the fabrication method used: Group A: CAD/CAM crowns using polymethyl methacrylate (PMMA) blocks and Group B: 3D dental printed crowns using GC photopolymer resin. All crowns were evaluated at baseline and at 3rd, 6th, and 12th months using the U.S. Public Health Service criteria for gingival health, retention, and marginal integrity for both groups.

Statistical Analysis The survival rate of 3D-printable crowns was 84% compared with 80% survival rate using CAD/CAM fabricated crowns at the end of the 12th-month follow-up. No statistically significant differences were noted in restoration failure. In the evaluation of gingival health between the two groups’ follow-up times, no statistically significant differences were noted at the 3rd- and 6th-month follow-ups, yet at the 12th month, statistically significant differences were noted (p = 0.022) when comparing gingival health. No statistically significant differences were noted between the two groups when comparing marginal integrity scores in all the follow-up periods.

Conclusion Resin crowns fabricated via 3D dental printer and PMMA crowns fabricated using CAD/CAM are acceptable esthetic choices in restoring pulp-treated primary molars with great marginal integrity and crowns retention. 3D-printed resin crowns showed less cementing failure and performed better regarding gingival response compared with PMMA crowns.
Factors Associated with Noncarious Cervical Lesions in Different Age Ranges: A Cross-sectional Study
Authors: Penoni Daniela Cia , Gomes Miranda Maria Elisa da Silva Nunes , Sader Flávia , Vettore Mario Vianna , Leão Anna Thereza Thomé
Published: February 2021

Objectives Understanding the possible risk factors of noncarious cervical lesion (NCCL) is important for prevention and clinical management of the condition. The aim of this study was to investigate the factors associated with the prevalence of NCCL among adolescents, adults, and elderly people.

Materials and Methods A cross-sectional study involving 501 participants aged 15 years or older was conducted. Participants were examined to assess the number of natural teeth and the prevalence and severity of NCCL by calibrated examiners. Data on age, gender, harmful toothbrushing habits, and acidogenic diet were collected through individual interviews. Multivariate Poisson’s regression models were used to evaluate the association between the independent variables and the prevalence of NCCL according to the three age groups: 15 to 39, 40 to 64, and 65 years or older.

Results The prevalence of NCCL among participants was 62.5% (95% confidence interval: 58.2–66.7). Among 15- to 39-year-old participants, the mean of NCCL was higher in males, those with lower number of teeth and acidogenic diet intake. Males aged 40 to 64 years and those with harmful brushing habits were more likely to present higher mean of NCCL. Elderly people with harmful toothbrushing habits had a greater mean of NCCL.

Conclusion Demographic (age and gender), clinical (number of teeth), and behavioral characteristics (harmful brushing habits and acidogenic diet) were meaningful factors associated with NCCL severity. The above-mentioned relationships varied between age groups.
A Retrospective Cohort Study on Mortality and Neurodevelopmental Outcomes of Preterm Very Low Birth Weight Infants Born to Mothers with Hypertensive Disorders of Pregnancy
Authors: Kono Yumi , Yonemoto Naohiro , Nakanishi Hidehiko , Hosono Shigeharu , Hirano Shinya , Kusuda Satoshi , Fujimura Masanori ,   for the Neonatal Research Network Japan
Published: February 2021

Objective We examined the effects of maternal hypertensive disorders of pregnancy (HDP) on the mortality and neurodevelopmental outcomes in preterm very low birth weight (VLBW) infants (BW ≤1,500 g) based on their intrauterine growth status and gestational age (GA).

Study Design We included singleton VLBW infants born at <32 weeks' gestation registered in the Neonatal Research Network Japan database. The composite outcomes including death, cerebral palsy (CP), and developmental delay (DD) at 3 years of age were retrospectively compared among three groups: appropriate for GA (AGA) infants of mothers with and without HDP (H-AGA and N-AGA) and small for GA (SGA) infants of mothers with HDP (H-SGA). The adjusted odds ratios (AOR) and 95% confidence intervals (CI) stratified by the groups of every two gestational weeks were calculated after adjusting for the center, year of birth, sex, maternal age, maternal diabetes, antenatal steroid use, clinical chorioamnionitis, premature rupture of membranes, non-life-threatening congenital anomalies, and GA.

Results Of 19,323 eligible infants, outcomes were evaluated in 10,192 infants: 683 were H-AGA, 1,719 were H-SGA, and 7,790 were N-AGA. Between H-AGA and N-AGA, no significant difference was observed in the risk for death, CP, or DD in any GA groups. H-AGA had a lower risk for death, CP, or DD than H-SGA in the 24 to 25 weeks group (AOR: 0.434, 95% CI: 0.202–0.930). The odds for death, CP, or DD of H-SGA against N-AGA were found to be higher in the 24 to 25 weeks (AOR: 2.558, 95% CI: 1.558–3.272) and 26 to 27 weeks (AOR: 1.898, 95% CI: 1.427–2.526) groups, but lower in the 30 to 31 weeks group (AOR: 0.518, 95% CI: 0.335–0.800).

Conclusion There was a lack of follow-up data; however, the outcomes of liveborn preterm VLBW infants of mothers with HDP depended on their intrauterine growth status and GA at birth.

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High Prevalence of Abnormal General Movements in Hospitalized Very Low Birth Weight Infants
Authors: Alonzo Corrie J. , Letzkus Lisa C. , Connaughton Elizabeth A. , Kelly Nancy L. , Michel Joseph A. , Zanelli Santina A.
Published: February 2021

Objective Abnormal general movements (GMs) are predictive of later risk of motor impairments in preterm infants. The goals of this study are to (1) describe the implementation of the GM assessment (GMA) in a neonatal intensive care unit (NICU) and (2) investigate the prevalence and evolution of abnormal GMs in very low birth weight (VLBW) infants.

Study Design Observational study of GMs in VLBW infants (gestational age [GA] <32 weeks and/or birth weight [BW] <1,500 g) following GMA implementation in a level-IV NICU. All VLBW infants admitted between November 2017 and April 2019 were eligible for the GMA. Infants were excluded if they required high-frequency ventilation or if they could not be unbundled for video acquisition. GMAs were scored weekly by at least 2 GMA-certified providers.

Results The GMA was performed in 121 VLBW infants with a mean (standard deviation [SD]) GA of 28.3 (2.6) and BW of 1,113 (400 g). Only 28% of infants had normal GMs on initial assessment (32.9 ± 2.7 weeks' GA), while 61 and 11% had poor repertoire and cramped-synchronized GMs, respectively. At NICU discharge (37.6 ± 3.4 weeks corrected GA), 45 and 21% of infants were classified as having poor repertoire and cramped-synchronized GMs, respectively. Most infants with cramped-synchronized GMs on initial assessment had persistent abnormal GMs at discharge. In contrast, only one infant with normal GMs on first assessment developed cramped-synchronized GMs.

Conclusion Abnormal GMs are common in VLBW infants, including a high prevalence of the more concerning cramped-synchronized movement pattern. The GMA can be successfully performed in VLBW infants. The GMA may be helpful in identifying infants at increased risk of later motor impairments, as well as assisting clinicians, in the stratification of infants who may benefit from additional brain imaging and/or an intensive hospital-based interventions.

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Climatizing the UN Security Council
Authors: Maertens Lucile
Published: February 2021

Since 2007, the United Nations Security Council (UNSC) has debated the security implications of climate change on several occasions. This article addresses these debates by exploring two interrelated questions: What drives the continuous efforts to place climate change on the UNSC’s agenda and to what extent do the UNSC’s debates illustrate an ongoing process of climatization? To answer these, the article draws on the concept of climatization, which captures the process through which domains of international politics are framed through a climate lens and transformed as a result of this translation. It suggests that climate change has become a dominant framing and an inescapable topic of international relations and that the UNSC debates follow a logic of expansion of climate politics by securing a steady climate agenda, attributing responsibility to the Council in the climate crisis, involving climate actors and advocating for climate-oriented policies to maintain international security.
Ground vibration characteristics induced by flood discharge of a high dam: An experimental investigation
Authors: Zhang Yan , Lian Jijian , Zhang Guoxin , Liu Yi , Song Mingming , Li Songhui
Published: February 2021

Upstream and downstream ground vibrations induced by flood discharge of high dams potentially cause damage in surrounding buildings and affect the living quality of local populations. Significant ground vibrations and some structural damages have been reported in the downstream area of Xiangjiaba Dam, a large-scale high dam located on Jinsha River, Yunnan, China. To study the characteristics of downstream vibration, a physical hydroelastic model is built to simulate discharge conditions and dynamic characteristics of the Xiangjiaba Dam. Hydroelastic models are traditionally built without special vibration isolation process; however, significant effects of ambient vibrations are observed. Therefore, a vibration isolation system has been built to reduce the effects of background vibration, including isolation trench, flexible connections, reinforced concrete foundation, and reasonable arrangement of water circulation system. High correlation coefficients are observed between hydroelastic model simulation and field measurements, which verifies the effectiveness of simulating the original discharge conditions using the hydroelastic model. Then a prediction model is created to predict downstream field measurements using model simulation data. The predictions generally agree with field observations well. Vibration energy distribution is analyzed among different structural components, which shows that orifices always have the highest energy contribution, and guide walls have significantly higher contribution when discharging through surface orifices. Furthermore, additional influential factors are studied which shows downstream vibrations generally increase with larger orifices openings, higher upstream water levels, and larger rate of flow.
Stochastic viscosity solutions for stochastic integral-partial differential equations
Authors: Wu Jinbiao
Published: February 2021

In order to study stochastic viscosity solutions for a class of semilinear stochastic integral-partial differential equations (SIPDEs), a new class of generalized backward doubly stochastic differential equations with general jumps is investigated. The definition of stochastic viscosity solutions of SIPDEs is introduced. A probabilistic representation for stochastic viscosity solutions of semilinear SIPDEs with nonlinear Neumann boundary conditions is given.
On spontaneous appearance of internal waves in an open-pool-type research reactor
Authors: Geva Meital , Bukai Moshe , Zemach Efi , Gabay Shani , Krakovich Alexander , Shemer Lev
Published: February 2021

Variation of temperature in time and space was recorded at multiple vertical locations in the course of initiation of a heated water layer in an open-pool research reactor of the Soreq Nuclear Research Center. The pool was initially filled with warm water, and heavier cooler water was then injected at the bottom of the facility. Different modes of coolant injection were employed in two different experiments. In both cases, a finite width thermocline that separated cool water at the lower part of the pool from the warm water in its upper part was observed. The thermocline gradually moved up eventually attaining a constant raise velocity. In both experiments, the thermocline characteristics were different, but wave-trains with notable temperature fluctuations were observed within the thermocline. The characteristic frequencies of oscillations were below the Brunt–Väisälä frequencies that characterize the density gradient within the thermoclines. The finite dimensions of the tank impose conditions in which standing internal waves with the length commensurate with tank size can be expected. The oscillations were thus associated with resonant internal waves excited by disturbances introduced by the coolant flow at the lower part of the pool. In both experiments, the measured wave spectra agree with the results of linear analysis of two-layer and three-layer stratification models.
Realization of high detectivity mid-infrared photodiodes based on highly mismatched AlInSb on GaAs substrates
Authors: Fujita H. , Sakurai Y. , Yasuda D. , Morohara O. , Geka H. , Suzuki M. , Shibata Y. , Kuze N.
Published: February 2021

We have systematically investigated highly mismatched AlInSb photodiodes grown on GaAs substrates operating in the mid-infrared range. A novel characterization method was introduced to analyze the recombination mechanism within an active layer of the devices, which revealed a high conductance stemming from the leaky behavior of dislocations. The introduction of a dislocation filter layer successfully reduced threading dislocations and improved resistance area product of photodiodes, leading to high detectivity at room temperature.
Topological trends in ionic transport through metal-oxide composites
Authors: Wen Yu , Hashimoto Ayako , Najib Abdillah Sani Bin Mohd , Hirata Akihiko , Abe Hideki
Published: February 2021

Although ionic conductors have been thoroughly investigated, topological features of these materials' nanotextures have been surprisingly overlooked. Here, we report fabrication of a metal-oxide nanocomposite consisting of intertwined phases of platinum (Pt) metal and oxygen-ion conductive cerium oxide (CeO2), i.e., Pt#CeO2. Sectional TEM observations coupled with topological analysis demonstrated that Pt#CeO2 composites having different nanostructures can be classified with a topological measure that corresponds to the phase connectivity of CeO2, namely, the Betti number β0, and another that corresponds to holes of the Pt phase, namely, the Betti number β1. The samples' oxygen ionic conductivity Pt#CeO2 was measured at elevated temperatures in air by alternating current impedance spectroscopy. It was found that the nanostructure changed from a striped appearance to a maze-like appearance as the value of β1/β0 decreased. Both the activation energy E and the pre-exponential factor σ0 for the oxygen ionic conductivity were found to be independent of β1 and exhibited linear, negative correlations with β0. The topological connectivity of the ion-conductive CeO2 phase, which was quantified with the Betti number β0, was suitable as a descriptor to correlate the image data of nanostructures with their ionic transport properties.
Perspective on ferroelectric, hafnium oxide based transistors for digital beyond von-Neumann computing
Authors: Breyer Evelyn T. , Mulaosmanovic Halid , Mikolajick Thomas , Slesazeck Stefan
Published: February 2021

Ferroelectric hafnium oxide (HfO2) has been extensively studied for over a decade, especially as a CMOS-compatible material in emerging memory applications. Most recently, it has gained a lot of attention for being applied in the field of beyond von-Neumann computing. The specific nature of different nonvolatile storage elements, particularly ferroelectric capacitors (FeCaps), tunnel junctions (FTJs), and field-effect transistors (FeFETs), dictates the boundary conditions of their adoption in “beyond von-Neumann” circuits and applications. While, for example, the scaling limits restrict the minimum feature size of FeCaps and FTJs, FeFETs have been proven to be highly scalable. On the other hand, HfO2-based FeFETs exhibit a lower cycling endurance than FeCaps, which has strong implications on their integration into circuits establishing beyond von-Neumann computing. This perspective points out some of the challenges that HfO2-based FeFETs encounter in reality and how they might be overcome by a suitable tuning of the device. Likewise, it is demonstrated how a suitable choice of application can partially or completely mitigate the imposed challenges.
Stability of a reverse Karman vortex street
Authors: Dynnikova G. Ya. , Dynnikov Ya. A. , Guvernyuk S. V. , Malakhova T. V.
Published: February 2021

The reverse vortex street differs from the ordinary Karman vortex street in the direction of the rotation of the vortices. Such a street is formed behind the oscillating airfoils in the flow. It is of interest in connection with studies of the aerodynamics of flapping wings. It is known that the vortex wake behind a symmetric airfoil performing symmetric oscillations in a certain range of parameters becomes asymmetric, which leads to the appearance of a nonzero average lift. Reasons of the symmetry violation are associated with the instability of the reverse vortex street, but the mechanism of this instability is currently not well understood. In this work, the analysis of the stability of the reverse vortex street is carried out on the basis of the theory developed by Karman for infinite rows of point vortices. In contrast to the Karman model, in this work, semi-infinite rows with periodically arising new vortices at their ends are considered. This is the first time this model has been used. It is shown that the periodic appearance of new vortices radically affects the characteristics of the street stability. It is found that the violation of the symmetry of the reverse vortex street is associated with its instability to bending perturbations, while the ordinary Karman vortex street behind the body is unstable to varicose perturbations. Regions of instability are determined.
Intrinsic memristive mechanisms in 2D layered materials for high-performance memory
Authors: Li Hao , Tao Li , Xu Jian-Bin
Published: February 2021

Two-dimensional layered materials such as graphene and transition metal dichalcogenides are promising candidates for developing high-density low-power next-generation memory. This Perspective reviews two major intrinsic memristive mechanisms in two-dimensional layered materials: polarization switching and resistive switching, which have high potentials for ferroelectric random access memory and in-memory computing, respectively. The potentials and challenges of these mechanisms for high-performance memory are also discussed with a futuristic insight.
Flows between orthogonally stretching parallel plates
Authors: Ayats R. , Marques F. , Meseguer A. , Weidman P. D.
Published: February 2021

Navier–Stokes equilibrium solutions of a viscous fluid confined between two infinite parallel plates that can independently stretch or shrink in orthogonal directions are studied. It is assumed that the admissible solutions satisfy spatial self-similarity in the stretching or shrinking perpendicular coordinates. The nonlinear steady boundary-value problem is discretized using a spectral Legendre method, and equilibrium solutions are found and tracked in the two-dimensional parameter space by means of pseudo-arclength continuation Newton–Krylov schemes. Different families of solutions have been identified, some of which are two-dimensional and correspond to the classical Wang and Wu self-similar flows arising in a plane channel with one stretching–shrinking wall [Wang, C.-A. and Wu, T.-C., “Similarity solutions of steady flows in a channel with accelerating walls,” Comput. Math. Appl. 30, 1–16 (1995)]. However, a large variety of three-dimensional solutions have also been found, even for low stretching or shrinking rates. When slightly increasing those rates, some of these solutions disappear at saddle-node bifurcations. By contrast, when both plates are simultaneously stretching or shrinking at higher rates, a wide variety of new families of equilibria are created and annihilated in the neighborhood of cuspidal codimension-2 bifurcation points. This behavior has similarities with the one observed in other planar and cylindrical self-similar flows.
Influence of surface sublimation on the stability of the supersonic boundary layer and the laminar–turbulent transition
Authors: Lysenko V. I. , Gaponov S. A. , Smorodsky B. V. , Kosinov A. D. , Yaroslavtsev M. I.
Published: February 2021

We report a theoretical study of the properties of a supersonic boundary layer and its linear stability under conditions of surface material sublimation. Calculations were performed for an adiabatic boundary layer for a flat plate with a naphthalene coating at a free-stream Mach number of M = 3 (for the first instability mode disturbances). In the boundary layer, surface sublimation generates a binary mixture flow (air and foreign vapors). This flow is studied using local self-similar boundary layer equations, and it is shown that the rise in the flow stagnation temperature and the corresponding evaporation of the wall material cause significant wall cooling and an increase in the near-wall density of the binary mixture. This modification of the boundary layer profiles leads to a decrease in the disturbance amplification rates. This is confirmed by calculations based on linear stability theory (LST). Boundary-layer stabilization occurs with an increase in stagnation temperature. The influence of surface sublimation on the position of the laminar–turbulent transition was estimated by means of the LST-based eN method. The possibility of increasing the transition Reynolds number by application of the sublimation coating is demonstrated. The results of pilot boundary layer transition experiments performed in a hot-shot wind tunnel are reported. For the first time, a delay in the transition due to the application of a naphthalene coating was experimentally demonstrated. It is also shown that surface sublimation leads to an increase in the growth rates of the second and third instability modes for a Mach 8 boundary layer.