bluuebunny/crossref_metadata_2025 huggingface dataset:
A Theoretical and Empirical Investigation of Feedback in Ideation Contests
Authors: Jiang Juncai , Wang Yu
Published: October 2019

Ideation contests are commonly used across public and private sectors to generate new ideas for solving problems, creating designs, and improving products or processes. In such a contest, a firm or an organization (the seeker) outsources an ideation task online to a distributed population of independent agents (solvers) in the form of an open call. Solvers compete to exert efforts and the one with the best solution wins a bounty. In evaluating solutions, the seeker typically has subjective taste that is unobservable to solvers. In practice, the seeker often provides solvers with feedback, which discloses useful information about her private taste. In this study, we develop a game‐theoretic model of feedback in unblind ideation contests, where solvers’ solutions and the seeker's feedback are publicly visible by all. We show that feedback plays an informative role in mitigating the information asymmetry between the seeker and solvers, thereby inducing solvers to exert more efforts in the contest. We also show that some key contest and solver characteristics (CSC, including contest reward, contest duration, solver expertise, and solver population) have a direct effect on solver effort. Interestingly, by endogenizing the seeker's feedback decision, we find that the optimal feedback volume increases with contest reward, contest duration, solver expertise, but decreases with solver population. Thus, CSC elements also have an indirect effect on solvers’ effort level, with feedback volume mediating this effect. Employing a dataset from Zhubajie.com , a leading online ideation platform in China, we find empirical evidence that is consistent with these theoretical predictions.
Strategic Capacity Planning Problems in Revenue‐Sharing Joint Ventures
Authors: Levi Retsef , Perakis Georgia , Shi Cong , Sun Wei
Published: October 2019

We study strategic capacity investment problems in joint ventures (JVs) with fixed‐rate revenue‐sharing contracts. We adopt a game‐theoretical approach to study two types of JVs depending on how individual resources determine the effective capacity of a JV. With complementary resources, the effective capacity of a JV is constrained by the most scarce resource. We show that multiple Nash equilibria could exist. Nevertheless, there exists a unique Strong Nash equilibrium. We show that there is an efficient and fair fixed‐rate revenue‐sharing contract which induces the system optimal outcome in the Strong Nash equilibrium. On the other hand, with substitutable a resource, the effective capacity of a JV is measured by aggregating individual contributions. We show that there does not exist a fixed‐rate revenue‐sharing contract that induces the system optimum. We quantify that the efficiency of a JV which decreases with the number of participants, the cost asymmetry and the cost margin of the JV. We propose provably‐good fixed‐rate revenue‐sharing contracts with performance guarantees. We also propose a simple modified contract to achieve the channel coordination. Finally, we fit our model with historical data to shed some insights on two JV examples in the motion picture industry.
Survival and early complications of preterm infants with birthweight less than 500 grams during a 10‐year period in Hungary
Authors: Varga Péter , Berecz Botond , Magyar Zsófia , Pete Barbara , Romicsné Görbe Éva , Dombi Zsófia Anna , Sassi Lilla , Fanczal Eszter , Ács Nándor , Kornya László , Joó József Gábor , Valek Andrea , Harmath Ágnes , Gasparics Ákos
Published: October 2019

Background

There are limited data available on the survival and early complications of preterm infants with less than 500 g birthweight. To estimate the outcomes for these infants, it is important for caregivers to be aware of perinatal factors that may affect survival.

Objectives

We assessed the mortality and certain early complications of preterm infants born with less than 500 g in Hungary between 2006 and 2015.

Methods

We reviewed data of 486 infants from the database of the Hungarian Central Statistical Office and in parallel of 407 infants from the “NICU database.” The study period was divided into two epochs: 2006‐2010 and 2011‐2015.

Results

The survival was 27.1% in the first epoch and 39.1% in the second epoch, and the incidence of early complications was slightly higher in the second epoch. In the surviving group (first and second epoch combined), gestational age (25.1 vs 23.7 weeks), birthweight (458 vs 447 g) antenatal steroid treatment (66.3% vs 52.3%), surfactant therapy (95.1% vs 84.3%), median Apgar scores (6 vs 3 and 8 vs 5 at 1 and 5 minutes, respectively) and proportion of caesarean delivery (89.3% versus 68.5%) were higher than in the non‐surviving group (first and second epoch combined). The proportion of multiple births was lower in the surviving group (15.7% vs 33.4%).

Conclusions

Survival of infants with less than 500 g improved between 2006‐2010 and 2011‐2015 in Hungary. The slightly higher occurrence of early complications might be associated with improving survival.
Expression frequency ofc‐kitisoforms and its prognostic potential in canine mammary tumours
Authors: Chen Yi‐Chen , Liao Jiunn‐Wang , Chang Shih‐Chieh , Hsu Wei‐Li
Published: October 2019

KIT is a tyrosine kinase receptor involved in carcinogenesis. Two alternatively spliced transcripts, differed from presence of four amino acids (GNSK) at exon 9 ofc‐kit, were identified in various human tumours and canine hemangiosarcoma (HSA). The biological function and clinical implications of these isoforms have not yet been elucidated in canine tumours. The current study aimed to validate the expression profile and ultimately to evaluate the correlation ofc‐kitisoform levels with clinicopathological factors of canine mammary tumours (CMTs). In total, the expression profiles ofc‐kitisoforms in 196 samples obtained from normal mammary glands (NMGs) of healthy controls and dogs with CMTs, benign and malignant CMTs, and HSAs were determined by polymerase chain reaction (PCR) and quantified via real‐time PCR. Overall, the expression levels of the two isoforms were equivalent in NMGs, whereas the GNSK−/GNSK+ratio sharply increased to 7.44‐ and 8.33‐fold, indicating abundant GNSK−isoforms in benign and malignant CMTs, respectively. However, a significant decrease in GNSK−expression was detected in dogs with high‐grade malignant CMTs (mCMTs) and with metastatic CMTs compared with expression in those with a lower grade and non‐metastatic CMTs. In addition, the median survival time was shorter in mCMT canines with a lower GNSK−/GNSK+ratio than that in mCMT canines with a higher ratio (899 days vs 1534 days). In conclusion, twoc‐kitisoforms are ubiquitously expressed with great variability in HSAs and CMTs with both benign and malignant status. The GNSK−/GNSK+ratio could serve as a prognostic indicator for dogs with mCMTs.
A card agglutination test for dog erythrocyte antigen 1 (DEA 1) blood typing in donor dogs: Determining an appropriate cutoff to detect positivity using a receiver operating characteristic curve
Authors: Proverbio Daniela , Perego Roberta , Baggiani Luciana , Spada Eva
Published: October 2019

Background

The appropriate cutoff to define a positive point‐of‐care card agglutination (CA) test for dog erythrocyte antigen 1 (DEA 1) blood typing depends on whether the test can be used in the donor or recipient.

Objectives

By screening for CA test positivity, we aimed to evaluate the best cutoff value for DEA 1 blood typing in canine blood donors using a receiver operator characteristic (ROC) curve.

Methods

Ethylenediaminetetraacetic acid (EDTA) blood samples from 100 canine blood donors were blood‐typed in parallel for DEA 1 using both immunochromatographic (IC) and CA tests. The effect of temperature, storage time, and anticoagulant solutions for both methods was evaluated. Unweighted and weighted Cohen's Kappa (K) statistic was calculated to evaluate the agreement between the two testing methods. The overall performance of the CA test was evaluated by generating a ROC curve using the IC test as the reference method.

Results

Concordant results were obtained for 86% of the samples. Unweighted and weighted K statistics demonstrated good and moderate agreement, respectively. For the CA test, the ROC curve showed an area under the curve (AUC) of 0.910, with the highest sensitivity cutoff values at ≥1+ agglutination. CA‐ and IC‐typed EDTA blood samples stored at room temperature for up to 1 week and refrigerated for up to 1 month were concordant as were the citrate phosphate dextrose adenine 1 (CPDA‐1) anticoagulated blood samples stored for up to 1 week at 4 ± 2°C.

Conclusions

The overall reliability of the CA method seemed to be lower than that of the IC method. When CA is used as a screening test for canine blood donors, the correct cut off is ≥1+ agglutination is recommended to maximize sensitivity.
The gift of life – does it apply to donation for research?
Authors: Raivola Vera
Published: October 2019

In his influential study, “The Gift Relationship” [1970], Richard Titmuss coined the idea of voluntary, non‐paid, blood donation being the gift of life for a fellow citizen. This metaphor has been powerful in mobilising donors. It conveys a direct relationship between blood donation and patients’ vitality, as well as a difference between gains and costs. As the gift of life, blood donation is seen to symbolise pure altruism and promoting solidarity between strangers. But can we apply the metaphor as successfully to donating blood for research? I interviewed a group of Finnish blood donors on what if theFRCBlood Service invited them to give a blood sample and personal information for research. The blood donors were usually willing to contribute to research for the public benefit, because they saw great potential in science to create solutions to help patients in the future. However, based on our interview data and previous research, I suggest that the analogy between the gift of life and donation for research did not work all the way. The metaphor fails to address donors’ questions on the new types of relationships, interests and risks related to the use of personal data for research. Left unanswered, these could discourage donating for research. Hence, I argue that the gift of life metaphor is not applicable to donor recruitment in the research context. I propose to look for new metaphors that resonate better with donors’ perceptions of research participation and serve the communication needs of data collectors.
La responsabilidad de validar el conocimiento científico y promover la formación en investigación en Odontología
Authors: Rivero Márquez Claudia Patricia , Delgado Troncoso Jorge Enrique , Delgado Troncoso Sandra Cecilia
Published: October 2019

Este editorial analiza algunas de las implicaciones de validar casi exclusivamente el trabajo investigativo y las revistas académicas arbitradas mediante sistemas de evaluación de revistas (índices), como Publindex en Colombia. Se reconoce la contribución que estos sistemas han hecho para mejorar la calidad de publicaciones y artículos pero enfatiza la necesidad de involucrar las comunidades académicas para determinar el valor del conocimiento y los procesos para generarlo. Se reflexiona también sobre el contexto de la investigación odontológica, las estrategias que Universitas Odontologica ha empleado para cumplir su misión y visión, y sus desafíos como revista institucional pequeña en odontología.
Vestibuloplastia con la técnica de Edlan Mejchar: descripción de cuatro casos clínicos
Authors: Díaz-Caballero Antonio José , Del Rio Rocha Daniel Gustavo , Harris Ricardo Jonathan
Published: October 2019

Antecedentes: En ocasiones, las retracciones gingivales se asocian a altas fuerzas tensionales de los músculos y a vestíbulos poco profundos. Dichas retracciones generan problemas periodontales a los pacientes por la dificultad de limpiar estas zonas. La vestibuloplastia por medio de la técnica de Edlan Mejchar permite, en una sola intervención y un solo campo quirúrgico, controlar los factores etiológicos y una inserción trepadora de la encía al eliminar las fuerzas tensionales. Objetivo: Describir la efectividad de la técnica de Edlan Mejchar empleada para solucionar retracciones gingivales producidas por fuerzas tensionales en cuatro casos clínicos. Descripción de los casos: Se presentaron cuatro pacientes con retracciones gingivales en dientes incisivos inferiores con poca encía adherida debida a fuerzas tensionales del frenillo labial inferior. Como tratamiento se usó la técnica de Edlan Mejchar que incluyó una incisión supraperióstica y relajantes internas en el tejido conjuntivo. Resultados: El porcentaje de cobertura radicular logrado después del procedimiento fue de aproximadamente el 60 % y se eliminaron inserciones anómalas del frenillo. Conclusiones: La técnica de Edlan Mejchar de vestibuloplastia mostró resultados favorables en los casos descritos en los cuales el frenillo labial ejercía fuerzas tensionales sobre el periodonto de dientes anteriores inferiores.
Frecuencia de quistes odontogénicos en pacientes de la Facultad de Odontología, Universidad Nacional de Colombia
Authors: Fajardo Ortiz Lizeth Vanessa , Peña Vega Claudia Patricia
Published: October 2019

Antecedentes: Los quistes odontogénicos se caracterizan por ser asintomáticos. Su hallazgo depende en un 80 % de imágenes radiográficas y en un 20 % de sintomatología esporádica. Colombia presenta pocos datos epidemiológicos sobre esta patología. Objetivo: Describir la frecuencia de los quistes odontogénicos, según la clasificación de la OMS del 2017, en los pacientes de la Facultad de Odontología de la Universidad Nacional de Colombia, sede Bogotá. Métodos: Se realizó un estudio descriptivo de corte transversal. Se seleccionaron historias clínicas con diagnóstico de quiste odontogénico corroborado por análisis histopatológico, y que tuvieran correctamente diligenciados los datos de edad, sexo y localización (zona afectada). Se usó la prueba de Fisher para evaluar independencia entre variables (p=0,05). Resultados: Los quistes odontogénicos más frecuentes fueron: quiste dentígero (66,6 %), quiste radicular (22,2 %) y queratoquiste odontogénico (11,2%). El 77,7 % se diagnosticó en hombres. 38.9 % de ellos se diagnosticaron entre la primera y segunda décadas de la vida (p=0,041) y la zona posterior mandibular fue la más afectada en un 44,4 % (p=0,017). Conclusiones: El quiste dentígero se presentó más durante la segunda década de la vida, en hombres y en la zona mandibular posterior. El quiste radicular no mostró predilección por un sexo, se presentó durante y después de la cuarta década de la vida y afectó la zona maxilar anterior. El queratoquiste odontogénico no tuvo predilección por sexo o zona afectada y se presentó en dos décadas de la vida diferentes.
Regulation of Tissue Engineered Devices in some Latin American Countries: Development and External Influences
Authors: Pineda Molina Catalina
Published: October 2019

Background: Emergence of new technologies and advances in tissue engineering strategies to treat diseases are shifting the conventional conception of medical devices. Tissue engineered products, manufactured as a combination of biomaterials, cells, and/or bioactive factors, are intended to temporarily restore an organ or tissue function, and induce the generation of newly site-appropriate functional tissue. Regulatory pathways for tissue engineered products require grouping policies controlling each of the components: materials, human cells, and active molecules. Purpose: To review current regulatory policies for medical devices (and within this, tissue engineered products), in a subset of Latin American countries, and to analyze the influence of international organizations and technological world power countries on policies of that subset. Methods: Top-down and horizontal diffusion models were employed to identify how regulatory policies have moved to Brazil, Colombia, Ecuador, Mexico, and Peru. Results: There are differences in technological appropriation to comprehensively define and classify medical devices. None of the countries have a definition of tissue engineered products. A top-down diffusion pattern was found to be associated with the current regulations. A horizontal diffusion is being applied as a regional effort to facilitate commercialization of medical products within Latin America. Conclusion: The concept of tissue engineered products is slowly arriving into the evaluated Latin American countries. Each country has the potential to take advantage of local institutions and regional and inter-regional coalitions to improve current guidelines and prepare the health system to the introduction of tissue engineered products.
Bio-Inspired Laminates of Different Material Systems
Authors: Liu J. L. , Lee H. P. , Lai K. S. , Tan V. B. C.
Published: October 2019

Helicoidal laminates mimicking the laminar structure of the exoskeleton of crustaceans have been reported to resist higher out-of-plane loads than the common cross-ply and quasi-isotropic fiber-reinforced laminates. Some have reported that smaller inter-ply angle improves strength of helicoidal laminates but others have reported the opposite. A few important material parameters that dictate the failure mechanism of helicoidal laminates have recently been proposed based on proof-of-concept carbon fiber-reinforced laminates, which is not the best material system to benefit from a helicoidal configuration. This study investigates the out-of-plane loading performance of helicoidal laminates with various inter-ply angles, ply thicknesses, and materials. Result shows that the failure mechanism is dictated by the competition between spiraling matrix split and delamination followed by fiber breakage regardless of the laminate material system. Spiraling matrix split resistance decreases as pitch (ratio of inter-ply angle to ply thickness) and matrix toughness decreases. This study provides guidelines for the optimization of helicoidal laminates. Coexistence of spiraling matrix split and fiber damage is often seen on the failed laminate with the highest peak load. The optimal inter-ply angle provides the optimal spiraling matrix split resistance; so, neither spiraling matrix split nor fiber/delamination damage becomes dominant. Since resistance to spiraling matrix split decreases as pitch or matrix toughness decreases, the optimal inter-ply angle will increase for laminates with weaker matrix or thicker plies and vice versa.
A Theoretical and Experimental Study on Extreme Stress Concentration-Free Designs of Circumferentially Notched Thin Cylindrical Shells
Authors: Shi Yunfeng , Wang Bo , Wu Hao , Wang Bin , Liu Changzhi , Li Rui
Published: October 2019

To ensure both adequate axial load-bearing capacity and radial vulnerability of a circumferentially notched thin cylindrical shell is one of the major challenges in designing some crucial aerospace structures such as the pyrotechnic separation devices. The most favorable design for such a shell is to optimize the notch geometry such that zero stress at the notch root is realized, which enhances the axial strength without impacting the notch failure during separation. However, few studies have focused on such extreme stress concentration-free designs of a single-side notch on a shell because the asymmetrical structure under common eccentric loading brings much difficulty for theoretical analysis, while numerical approaches can hardly meet the requirements of highly efficient rapid optimal designs. In this paper, a theoretical and experimental study toward extreme stress concentration-free designs of single-side-notched thin cylindrical shells is presented. The general stress concentration factors (SCFs) for single-side notches with arbitrary depths are obtained based on the theory of notch stresses, which are well validated by the refined finite element modeling. An important finding reveals that, for a common notched shell in aerospace vehicles, the stress at the notch root approaches zero when a specific ratio of load eccentricity to minimum section width is attained. Comprehensive experiments for specially designed notched specimens confirm the theoretical finding. The present study provides an effective approach to analyzing single-side-notched structures and yields an explicit quantitative guideline for the optimal design of circumferentially notched thin cylindrical shells.
Visualization Technology and Tool Selection Methods for Solving Adaptive Training Complex Structural-Parametric Synthesis Problems
Authors: Krasnyanskiy Mikhail N. , Dedov Denis L. , Obukhov Artem D. , Alekseev Sergey Yu
Published: October 2019

Our previous work in the field of formalization, modeling, and design of adaptive training complexes (ATCs) revealed the low accuracy of the traditional expert approach to selecting ATC components. The study addresses the practical scientific problem of classifying and selecting visualization tools and technologies for designing ATC. Currently, this is done using highly subjective expert evaluation. Therefore, we develop a methodology for the selection of visualization tools and technologies to reduce the influence of the human factor by applying a set of main criteria for visualization component evaluation. Classification is based on the facet approach. We create an original technique that allows users to formalize the main objects of a technical system needing a training complex. It allows users to correlate these aspects to the visualization components and to group, evaluate, and rank them. Integration time, use-cost and component visualization quality, training quality, and time are important variables in the methodology. The use of lexicographic optimization methods or linear convolution of criteria is proposed to obtain an optimal solution from the final Pareto-set. The proposed component selection method has several advantages, compared with the classical approach: greater objectivity of the obtained estimates, better development, and further software implementation automation. Thus, this method addressed the problem of choosing the components of ATC visualization. The significance of the study is in the development of the original algorithmic and mathematical software for the method of selecting ATC visualization components.
Data-Driven Predictive Modeling of Tensile Behavior of Parts Fabricated by Cooperative 3D Printing
Authors: Zhang Ziyang , Poudel Laxmi , Sha Zhenghui , Zhou Wenchao , Wu Dazhong
Published: October 2019

3D printing has been extensively used for rapid prototyping as well as low-volume production in aerospace, automotive, and medical industries. However, conventional manufacturing processes (i.e., injection molding and CNC machining) are more economical than 3D printing for high-volume mass production. In addition, current 3D printing techniques are not capable of fabricating large components due to the limited build size of commercially available 3D printers. To increase 3D printing throughput and build volume, a novel cooperative 3D printing technique has been recently introduced. Cooperative 3D printing is an additive manufacturing process where individual mobile 3D printers collaborate on printing a part simultaneously, thereby increasing printing speed and build volume. While cooperative 3D printing has the potential to fabricate larger components more efficiently, the mechanical properties of the components fabricated by cooperative 3D printing have not been systematically characterized. This paper aims to develop a data-driven predictive model that predicts the tensile strength of the components fabricated by cooperative 3D printing. Experimental results have shown that the predictive model is capable of predicting tensile strength as well as identifying the significant factors that affect the tensile strength.
A Coarse-Grained Regularization Method of Convolutional Kernel for Molten Pool Defect Identification
Authors: Liu Tianyuan , Bao Jinsong , Wang Junliang , Zhang Yiming
Published: October 2019

Machine vision has a wide range of applications in the field of welding. The rise of convolutional neural network (CNN) provides a new way to extract visual features of welding. Due to the limitation of the small size of our molten pool dataset, the regularization of the CNN model is necessary to prevent overfitting. We propose a coarse-grained regularization method for convolution kernels (CGRCKs), which is designed to maximize the difference between convolution kernels in the same layer. The algorithm performance was tested on our self-made dataset and other public datasets. The results show that the CGRCK method can extract multi-faceted features. Compared with L1 or L2 regularization, the proposed method works great on CNNs and introduces little overhead cost to the training.
Design, Fabrication, and Testing of a Novel 3-DOF Energy Harvester With Single Piezoelectric Stack
Authors: Wu Zehao , Xu Qingsong
Published: October 2019

This paper presents the design, fabrication, and testing of a novel single stack-based piezoelectric energy harvester (PEH) for harvesting energy from three-degree-of-freedom (3-DOF) force excitation. One uniqueness lies in that the 3-DOF energy harvesting is implemented by using one piezoelectric stack. To scavenge energy from the 3-DOF input force, the proposed PEH is constructed with several force transmission mechanisms and slider mechanisms. The direction of the input force is first changed by the force transmission mechanisms, and the redundant force components are eliminated by the slider mechanisms. The transmitted force is then amplified by a two-stage force amplifier mechanism to improve the electric power output. The key parameters were found by establishing an analytical model of the proposed PEH. The best output performance of the PEH is achieved by selecting and optimally designing the key parameters. A prototype harvester was fabricated, and several experimental studies were conducted to verify the device performance. Results show the effectiveness of the developed 3-DOF PEH under the input force applied in x-axis, y-axis or z-axis. Furthermore, the issues that affect the practical application are discussed.
Giant nonlinear damping in nanoscale ferromagnets
Authors: Barsukov I. , Lee H. K. , Jara A. A. , Chen Y.-J. , Gonçalves A. M. , Sha C. , Katine J. A. , Arias R. E. , Ivanov B. A. , Krivorotov I. N.
Published: October 2019

Nonlinear magnon scattering redefines how nanomagnets respond to spin currents.
Nanoscale mapping of chemical composition in organic-inorganic hybrid perovskite films
Authors: Szostak R. , Silva J. C. , Turren-Cruz S.-H. , Soares M. M. , Freitas R. O. , Hagfeldt A. , Tolentino H. C. N. , Nogueira A. F.
Published: October 2019

Synchrotron infrared nanospectroscopy shed light on the nanoscale chemical heterogeneities in hybrid perovskites for solar cells.
Water nanostructure formation on oxide probed in situ by optical resonances
Authors: Yin Yin , Wang Jiawei , Wang Xiaoxia , Li Shilong , Jorgensen Matthew R. , Ren Junfeng , Meng Sheng , Ma Libo , Schmidt Oliver G.
Published: October 2019

Dynamics of water nanostructure formation on oxide surface is probed in situ by optical resonances.
Drug reaction with eosinophilia and systemic symptoms syndrome in a patient taking lamotrigine
Authors: Lameiras Catarina , Ornelas Énia , Mendes Lopes Marta , Dória Maria do Céu
Published: October 2019

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a rare adverse drug reaction characterised by skin eruption and multiple organ involvement. Diagnosing this entity is challenging due to the variability of clinical manifestations, late onset and relapse even after stopping the causative drug. It is potentially life-threatening; thus, it must be promptly recognised and the causative drug withdrawn. We describe a case of a 50-year-old man with an acute diffuse rash, fever and eosinophilia 4 weeks after having started lamotrigine. The suspected eliciting drug was suspended and systemic corticoid treatment was initiated (prednisolone 0.5 mg/kg/day). Symptoms relapsed under corticoid tapering with greater severity. The patient developed an exuberant rash associated with peripheral lymphadenopathies, marked eosinophilia and hepatic cytolysis. The diagnosis of DRESS syndrome to lamotrigine was made. Prednisolone dosage was increased to 1 mg/kg/day, and the subsequent taper was performed slowly over the course of 10 weeks. Full clinical remission was observed.
Heterochromia irides and mistaken identity of retinoblastoma
Authors: Abu-Ain Moh'd Saleh , Shatnawi Raed , Yousef Yacoub A , Watts Patrick
Published: October 2019

Retinoblastoma is the most common intraocular malignancy of infancy which frequently manifests with a white pupillary reflex. We report a case of delayed presentation of a child with retinoblastoma in his left eye because parents thought the change in iris colour in this eye was due to the innocent heterochromia irides that was previously diagnosed in his elder sibling. This late presentation necessitated enucleation of the affected eye followed by chemotherapy.
Successful treatment of gastric necrosis after ingestion of hydrochloric acid: a two-stage minimally invasive surgical procedure
Authors: Rasbach Erik , Schölch Sebastian , Reissfelder Christoph , Rahbari Nuh N
Published: October 2019

Caustic ingestion may cause devastating injuries of the upper gastrointestinal tract and the respiratory system. We report here the successful treatment of a 37-year-old patient who ingested hydrochloric acid (100 mL; 24%) in suicidal intention. An oesophagogastroduodenoscopy revealed extensive necrosis of the gastric mucosa. A diagnostic laparoscopy was performed and confirmed the suspected transmural necrosis which resulted in a discontinuous laparoscopic gastrectomy. During the next days, the oesophageal stump was monitored through frequent oesophagoscopies and showed a good recovery. Thus, it was possible to restore continuity as early as by the sixth postoperative day performing a roux-en-y oesophagojejunostomy using theda VinciXi surgical robot. The patient underwent all procedures without any surgical complications and was discharged almost 1 month after initial presentation in good general condition.
Amiodarone-induced diffuse alveolar haemorrhage: a rare but potentially life-threatening complication of a commonly prescribed medication
Authors: Saeed Jamaluddin , Waqas Qazi Ahmed , Khan Uzma Ikhtiar , Abdullah Hafez Mohammad Ammar
Published: October 2019

Amiodarone is an antiarrhythmic agent that is used commonly in clinical practice. It is associated with many side effects, the most common being pulmonary manifestations. Interstitial pneumonitis is one of the most common complications, however rarely amiodarone can cause diffuse alveolar haemorrhage (DAH) too. We describe the case of a 73-year-old woman who presented with shortness of breath and haemoptysis 4 days after starting amiodarone. She was diagnosed with amiodarone-induced DAH based on imaging and bronchoalveolar lavage. She was treated with intravenous and then oral steroids, and amiodarone was discontinued. The patient made a significant clinical and radiological recovery. She was discharged 10 days after her presentation. This case highlights a rare but potentially life-threatening complication of a commonly used medication.
Prognostic accuracy of qSOFA in predicting 28-day mortality among infected patients in an emergency department: a prospective validation study
Authors: Abdullah S M Osama Bin , Sørensen Rune Husås , Dessau Ram Benny Christian , Sattar Saifullah Muhammed Rafid Us , Wiese Lothar , Nielsen Finn Erland
Published: October 2019

Background

Few prospective studies have evaluated the quick Sequential (Sepsis-Related) Organ Failure Assessment (qSOFA) criteria in emergency department (ED)settings. The aim of this study was to determine the prognostic accuracy of qSOFA compared with systemic inflammatory response syndrome (SIRS) in predicting the 28-day mortality of infected patients admitted to an ED.

Methods

A prospective observational cohort study of all adult (≥18 years) infected patients admitted to the ED of Slagelse Hospital, Denmark, was conducted from 1 October 2017 to 31 March 2018. Patients were enrolled consecutively and data related to SIRS and qSOFA criteria were obtained from electronic triage record. Information regarding mortality was obtained from the Danish Civil Registration System. The original cut-off values of ≥2 was used to determine the prognostic accuracy of SIRS and qSOFA criteria for predicting 28-day mortality and was assessed by analyses of sensitivity, specificity, positive predictive value, negative predictive value, likelihood ratios and area under the receiver operating characteristic curve (AUROC) with 95% confidence intervals (CI).

Results

A total of 2112 patients were included in this study. A total of 175 (8.3%) patients met at least two qSOFA criteria, while 1012 (47.9%) met at least two SIRS criteria on admission. A qSOFA criteria of at least two for predicting 28-day mortality had a sensitivity of 19.5% (95% CI 13.6% to 26.5%) and a specificity of 92.6% (95% CI 91.4% to 93.7%). A SIRS criteria of at least two for predicting 28-day mortality had a sensitivity of 52.8% (95% CI 44.8% to 60.8%) and a specificity of 52.5% (95% CI 50.2% to 54.7%). The AUROC values for qSOFA and SIRS were 0.63 (95% CI 0.59 to 0.67) and 0.52 (95% CI 0.48 to 0.57), respectively.

Conclusion

Both SIRS and qSOFA had poor sensitivity for 28-day mortality. qSOFA improved the specificity at the expense of the sensitivity resulting in slightly higher prognostic accuracy overall.
Non-trivial effects of sourceless forces for spinors: toward an Aharonov–Bohm gravitational effect?
Authors: Fabbri Luca , Moulin Flora , Barrau Aurélien
Published: October 2019

Spinor fields are written in polar form so as to compute their tensorial connection, an object that contains the same information of the connection but which is also proven to be a real tensor. From this, one can still compute the Riemann curvature, encoding the information about gravity. But even in absence of gravity, when the Riemann curvature vanishes, it may still be possible that the tensorial connection remains different from zero, and thih can have effects on matter. This is shown with examples in the two known integrable cases: the hydrogen atom and the harmonic oscillator. The fact that a spinor can feel effects due to sourceless actions is already known in electrodynamics as the Aharonov–Bohm phenomenon. A parallel between the electrodynamics case and the situation encountered here will be drawn. Some ideas about relativistic effects and their role for general treatments of quantum field theories are also underlined.
Gallium Oxide Field Effect Transistors — Establishing New Frontiers of Power Switching and Radiation-Hard Electronics
Authors: Wong Man Hoi , Higashiwaki Masataka
Published: October 2019

Ga2O3 has gained worldwide interests for next-generation power electronics because its large critical field strength stemming from an ultra-wide bandgap promises miniaturized circuits and systems with high conversion efficiency. Intense pursuit of Ga2O3 power devices stimulated by early demonstrations of high-voltage Ga2O3 field effect transistors (FETs) has brought about tremendous advancements in this new technology, whose strong radiation tolerance and high thermal stability also befit harsh-environment applications. In this paper, we review the various types of depletionand enhancement-mode Ga2O3 FETs — which have predominantly been lateral devices — for power switching and radiation-hard electronics. The development of vertical Ga2O3 transistors based on a low-cost, highly-manufacturable ion implantation doping process will also be discussed.
Application of Atom Probe Tomography for Advancing GaN Based Technology
Authors: Licata Olivia G. , Mazumder Baishakhi
Published: October 2019

Atom Probe Tomography (APT) has emerged as a stand-alone technique for material characterization at the sub-nanometer level, with unrivaled spatial resolution, coupled with three-dimensional atomic mapping, and equal sensitivity of all elements. Over the past decade, APT has proven to be a valuable tool in advancing the understanding and design of GaN-based semiconductor technology, by revealing correlations between atomic-level structure chemistry and device performance. The uniqueness of APT is exemplified by its ability to directly analyze nanoscale features within a commercial device. In this review, the quantitative requirements for advancement in GaN-based device metrology are defined as accurate measurement of composition, structural inhomogeneities, elemental incorporation within thin interlayers, and quantification of dopants and impurities. These are bolstered by a review of recent advances in GaN-based devices, realized through APT. The rich compositional and spatial data provided by APT is necessary for the continued advancement of III-V semiconductor technology.
Ultra-Wide Bandgap AlxGa1-xN Channel Transistors
Authors: Razzak Towhidur , Rajan Siddharth , Armstrong Andrew
Published: October 2019

High Al-composition AlxGa1-xN, an emerging class of materials, is gaining significant traction due to its high critical breakdown electric field exceeding that of GaN and high electron saturation velocity that is comparable to GaN. High Al-composition AlxGa1-xN holds promise for applications such as highly scaled next generation RF devices and power devices. However, significant strides remain to be made before AlxGa1-xN can take a share of the limelight. Encouraging progress has been made in recent years, including multiple reports of RF operation of AlxGa1-xN channel transistors with reported unity current gain cutoff frequency as high as 40 GHz, high current density devices with the maximum reported current density exceeding 600 mA/mm and reports of breakdown fields in lateral transistors that are almost 3× the reported breakdown field for GaN channel devices of similar dimensions. This paper focuses on the lateral devices demonstrated thus far and discusses breakthrough performance results achieved for AlxGa1-xN channel transistors together with the key challenges that are yet to be properly addressed. The paper starts with a discussion of contact formation to AlxGa1-xN films – the key difficulty of fabricating AlxGa1-xN transistors. This is followed by a discussion of the types of devices that are typically used. This is followed up with a discussion of the approach required to make high quality devices with AlxGa1-xN as a template together with some recent result highlights.
Multiquark states in the Thomas–Fermi quark model and on the lattice
Authors: Wilcox Walter , Baral Suman
Published: October 2019

We describe work being done at Baylor University investigating the possibility of new states of mesonic matter containing two or more quark–antiquark pairs. To put things in context, we begin by describing the lattice approach to hadronic physics. We point out there is a need for a quark model which can give an overall view of the quark interaction landscape. A new application of the Thomas–Fermi (TF) statistical quark model is described, similar to a previous application to baryons. The main usefulness of this model will be to detect systematic energy trends in the composition of the various particles. It could be a key to identifying families of bound states, rather than individual cases. Numerical results based upon a set of parameters derived from a phenomenological model of tetraquarks are given.
Tetrads in SU(N) Yang–Mills geometrodynamics
Authors: Garat Alcides
Published: October 2019

The discovery of the [Formula: see text] symmetry was fundamental as to establishing an ordering principle in particle physics. We already studied how to couple the [Formula: see text] symmetry to the gravitational field in four-dimensional curved Lorentzian space–times. The multiplets of equal quantum numbers are translated through natural elements in Riemannian geometry into local multiplets of equal gravitational field. As quark physics developed since in the 1970s, it was necessary to incorporate new symmetries to the models, that ensued in the incorporation of new quantum numbers like charm, for example, charm is an additive quantum number like isospin [Formula: see text] and hypercharge [Formula: see text] and the standard [Formula: see text] diagrams were extended onto another third axis. Then, instead of the fundamental triplet, we have a quartet [Formula: see text] as the smallest representation of the symmetry group, leading to the introduction of [Formula: see text] as the new group of symmetries. In this paper, we will not restrict ourselves exclusively to the symmetry group [Formula: see text] and we will set out to analyze the coupling of the [Formula: see text] symmetry to the gravitational field. To this end, new tetrads will be introduced as we did for the [Formula: see text] case. These tetrads have outstanding properties that enable these constructions. New theorems will be proved regarding the isomorphic nature of these local symmetry gauge groups and tensor products of groups of local tetrad transformations. This is a paper about grand field unification in four-dimensional curved Lorentzian space–times.
Design of Optimal Two-Dimensional FIR Filters with Quadrantally Symmetric Properties Using Vortex Search Algorithm
Authors: Yadav Suman , Yadav Richa , Kumar Ashwni , Kumar Manjeet
Published: October 2019

This research paper presents a new evolutionary technique named vortex search optimization (VSO) to design digital 2D finite impulse response (FIR) filter for improved performance both in pass-band and stop-band regions. Optimum filter coefficients are calculated by minimizing the deviation of actual frequency response from specified or desired response. Efficiency of the designed filter is measured by several parameters, such as maximum pass-band ripple, maximum stop-band ripple, mean attenuation in stop band and time taken, to execute the code. Analysis of the performance of designed filter is correlated with various different algorithms like real coded genetic algorithm, particle swarm optimization, genetic search algorithm and hybrid particle swarm optimization gravitational algorithm. Comparative study shows significant reduction in pass-band error, stop-band error and execution time.
Fast Detection of Degenerate Predicates in Free Space Construction
Authors: Milenkovic Victor , Sacks Elisha , Butt Nabeel
Published: October 2019

An implementation of a computational geometry algorithm is robust if the combinatorial output is correct for every input. Robustness is achieved by ensuring that the predicates in the algorithm are evaluated correctly. A predicate is the sign of an algebraic expression whose variables are input parameters. The hardest case is detecting degenerate predicates where the value of the expression equals zero. We encounter this case in constructing the free space of a polyhedron that rotates around a fixed axis and translates freely relative to a stationary polyhedron. Each predicate involved in the construction is expressible as the sign of a univariate polynomial [Formula: see text] evaluated at a zero [Formula: see text] of a univariate polynomial [Formula: see text], where the coefficients of [Formula: see text] and [Formula: see text] are polynomials in the coordinates of the polyhedron vertices. A predicate is degenerate when [Formula: see text] is a zero of a common factor of [Formula: see text] and [Formula: see text]. We present an efficient degeneracy detection algorithm based on a one-time factoring of all the univariate polynomials over the ring of multivariate polynomials in the vertex coordinates. Our algorithm is 3500 times faster than the standard algorithm based on greatest common divisor computation. It reduces the share of degeneracy detection in our free space computations from 90% to 0.5% of the running time.
Recent advances in the field of artificial hemoproteins: New efficient eco-compatible biocatalysts for nitrene-, oxene- and carbene-transfer reactions
Authors: Kariyawasam Kalani , Ricoux Rémy , Mahy Jean-Pierre
Published: October 2019

In the last few years, the field of artificial hemoproteins has been expanding through two main strategies involving either the incorporation of synthetic metalloporphyrin derivatives into the chiral cavity of a protein or the directed evolution of natural hemoproteins such as myoglobin and cytochromes P450. First, various synthetic water-soluble porphyrins including ions of transition metals such as iron and manganese have been inserted covalently or by supramolecular anchoring into non-specifically designed native proteins or into proteins modified by a minimum number of mutations. The obtained artificial hemoproteins were able to catalyze oxene transfer reactions such as epoxidation of alkenes or sulfoxidation of sulfides and cyclopropanation reactions with good activities and moderate enantioselectivities. Recently, a second approach, based on the design of the active site of already existing native hemoproteins such as myoglobin and cytochromes P450 by directed evolution, has led to new artificial hemoproteins that are able to catalyze oxene transfer reactions with improved activities as well as with abiological reactions. This approach thus provided promising tools for the catalysis of reactions such as intramolecular or intermolecular carbene and nitrene transfer reactions with high efficiencies. In addition, in all cases, after a few rounds of mutagenesis, mutants that were able to catalyze those reactions with a high enantioselectivity could be obtained. Finally, several groups showed that these new artificial metalloenzymes could also be used for the preparative scale-production of compounds with an excellent enantioselectivity, opening new pathways for the industrial synthesis of compounds of pharmaceutical interest.
Central values of GL(2) ×GL(3) Rankin–Selberg L-functions
Authors: Pi Qinghua
Published: October 2019

Let [Formula: see text] be a normalized holomorphic cusp form for [Formula: see text] of weight [Formula: see text] with [Formula: see text]. By the Kuznetsov trace formula for [Formula: see text], we obtain the twisted first moment of the central values of [Formula: see text], where [Formula: see text] varies over Hecke–Maass cusp forms for [Formula: see text]. As an application, we show that such [Formula: see text] is determined by [Formula: see text] as [Formula: see text] varies.
Treebanks in Historical Syntax
Authors: Taylor Ann
Published: October 2019

Over the last 20 years, the development of a wide range of treebanks that track the evolution of languages’ syntactic patterns through time has revolutionized the field of historical syntax. The range of treebanks now available facilitates research into the long histories of many of the major Indo-European languages. Although the field's essentially corpus-based methodology has not changed, the quantity of data now available and the ease and precision with which those data can be extracted have created new opportunities. For example, with a treebank it is possible to extract all examples of surface strings associated only with abstract structures (e.g., relative clauses, extraposition), to investigate predictions made by syntactic analyses, to search for rare constructions, and to extract enough data to support sophisticated statistical analyses. Crucially, treebanks make verification and replicability of results possible.