bluuebunny/crossref_metadata_2025 huggingface dataset:
Augmentative and Alternative Communication for Adults With Complex Communication Needs: A Review of Single-Case Research
Authors: Andzik Natalie R. , Chung Yun-Ching
Published: February 2021

The authors conducted a systematic review of the literature, including studies that used a single-case design (SCD) and taught augmentative and alternative communication (AAC) use to adults with complex communication needs. The purpose of this review was to describe (a) adults receiving AAC intervention, (b) components of the interventions used, and (c) how the literature met quality standards set by the What Works Clearinghouse (WWC). Across the 12 SCD studies included, a total of 28 adults with complex communication needs received intervention. As part of the intervention, the majority of the participants ( n = 24; 86%) were introduced to new AAC systems (e.g., picture, communication application). Ten of 12 studies showed at least moderate evidence of effectiveness. Only three of 12 studies met the WWC standards without reservation. Findings from this review call for action to ensure quality AAC access and services are available to adults with complex communication needs.
The non-operative management of bony mallet injuries
Authors: Trickett Ryan W. , Brock James , Shewring David J.
Published: February 2021

Over a 4-year period, 218 mallet fractures in 211 adult patients were treated using a custom-made thermoplastic splint. Clinical results were collected prospectively, including the visual analogue score for pain, the range of motion and extensor lag, and the Patient Evaluation Measure (PEM). The joints were congruent in 168 and subluxed in 50. There were no differences in range of movement, extensor lag or PEM associated with articular subluxation or the size of the articular fragment. Pre-existing joint degeneration did not influence outcome. Non-surgical treatment demonstrates predictably good outcomes regardless of fragment size or subluxation in most patients and should be considered when discussing treatment for patients with bony mallet fractures.

Level of evidence: III
The mechanics of a climbing fall with a belayer who can be lifted
Authors: Leuthäusser Ulrich
Published: February 2021

In sport climbing, a common method of belaying is to use a static rope brake attached to the belayer’s harness, but the belayer can move freely. This paper investigates the dynamics of a climbing fall with such a belayer. The dynamics are nontrivial because of the belayer’s constraint to be always at or above his initial position. An exact solution for a linear elastic rope is presented. Compared to a fix-point belay, one obtains a considerable force reduction on the belay-chain. However, there is a trade-off of a longer stopping distance of both climber and belayer. In order to calculate the stopping distance, friction between rope and the top carabiner has been taken into account. Closed-form formulas allow for calculating the maximum impact force, as well as the minimum mass of the belayer which is necessary to hold a fall from a certain height.
Health inequities and technological solutions during the first waves of the COVID-19 pandemic in high-income countries
Authors: Mac-Seing Muriel , Rocha de Oliveira Robson
Published: February 2021

The COVID-19 pandemic has resulted in massive disruptions to public health, healthcare, as well as political and economic systems across national borders, thus requiring an urgent need to adapt. Worldwide, governments have made a range of political decisions to enforce preventive and control measures. As junior researchers analysing the pandemic through a health equity lens, we wish to share our reflections on this evolving crisis, specifically: (a) the tenuous intersections between the responses to the pandemic and public health priorities; (b) the exacerbation of health inequities experienced by vulnerable populations following decisions made at national and global levels; and (c) the impacts of the technological solutions put forward to address the crisis. Examples drawn from high-income countries are provided to support our three points.
Impact of Initial eGlycemic Management System Dosing Strategy on Time to Target Blood Glucose Range
Authors: Emamdjomeh Amir S. , Warren Jamie N. , Harper Courtney L. , Olin Jacqueline L.
Published: February 2021

Background:

Glucommander™ (GM), an electronic glycemic management system, was implemented across a multi-hospital health system as the standard of care for glycemic control. GM provides insulin dosing recommendations based on patient-specific blood glucose (BG) trends after providers select either a custom dose or weight-based multiplier as the initial dosing strategy for the first 24 hours. This study evaluated the impact of initial subcutaneous (SC) GM insulin dosing strategies on glycemic management.

Methods:

Non-intensive care unit patients treated with SC GM using either initial custom (based on provider discretion) or weight-based multiplier settings (0.3, 0.5, or 0.7 units/kg/day) were evaluated in this retrospective chart review. The primary endpoint was time to target BG range defined as time to first two consecutive in range point of care BG. Secondary endpoints included percentage of BG values in target range, percentage of orders following institutional recommendations, length of stay (LOS), average BG, and incidence of hypoglycemia and hyperglycemia.

Results:

A review of 348 patients showed time to target BG was not significantly different between custom and multiplier groups (55 vs 64 hours, P = .07). Target BG was achieved in less than half of patients in both groups (47% vs 44%, respectively). There were no differences in hospital LOS, proportion of BG in target range, rates of hypo/hyperglycemia, and average BG.

Conclusions:

Custom initial SC GM insulin dosing settings showed a nonsignificant decrease in time to target BG range compared to pre-defined multiplier settings. Future studies evaluating the impact of compliance with institutional recommendations on BG control are warranted.
Carfilzomib-induced pulmonary hypertension with associated right ventricular dysfunction: A case report
Authors: McGregor Pei-Chun , Boosalis Valia , Aragam Jayashri
Published: February 2021

Carfilzomib, a selective proteasome inhibitor, is approved for use in relapsed and refractory multiple myeloma. Its link to left ventricular dysfunction is well established but little is known about its effects on the right ventricle. One of its rare complications is pulmonary hypertension, which at its extreme may result in right ventricular dysfunction. Here, we present a case of an elderly male veteran with multiple myeloma status post various failed therapies who developed acute dyspnea after four cycles of carfilzomib and subsequently found to have severe pulmonary hypertension with resultant acute right ventricular failure, which recovered after cessation of carfilzomib. This case highlights the need for careful cardiovascular surveillance while on carfilzomib and the importance of knowing even its rarest complications as these cardiotoxicities are reversible with discontinuation of the drug.
Invasive fungal rhinitis with adnexal involvement caused by Histoplasma capsulatum in a cat from a non-enzootic location
Authors: Grinstead Catherine R , Hanzlicek Andrew S , Largura Heather W , Wheat L Joseph
Published: February 2021

Case summary

This report describes a cat with a rare form of histoplasmosis: invasive rhinitis with adnexal involvement, mimicking disease more commonly caused by cryptococcosis or aspergillosis. This case is especially noteworthy as it was from an area where histoplasmosis is not enzootic.

Relevance and novel information

Invasive fungal rhinitis causes significant morbidity in cats. Diagnostic investigation of more common pathogens includes detection of fungal antigen ( Cryptococcus) or antifungal antibodies ( Aspergillus). This case demonstrates that histoplasmosis can present as chronic nasal disease in cats. Histoplasma antigen testing provides a non-invasive diagnostic option. Moreover, this case serves as a reminder that histoplasmosis can affect cats anywhere, even in non-enzootic areas.
Infant Stroke Associated With Left Atrial Thrombus and Supraventricular Tachycardia
Authors: Pauley Rachel , Mercier Elise L. , Kumar Ashutosh , Trescher William H. , Mainali Gayatra
Published: February 2021

We report a rare case of cardioembolic stroke in the setting of supraventricular tachycardia (SVT) in an infant. After a week of irritability, a 10-week-old male presented to the emergency department with SVT requiring treatment with adenosine. He developed right-sided hemiparesis and focal motor seizures. Imaging of the brain showed ischemic infarct in the left middle cerebral artery (MCA) territory. Echocardiogram showed a newly formed large left atrial intracardiac thrombus. A coagulopathy workup was negative. He was treated with beta-blocker and anticoagulation therapy. He had mild residual right hemiparesis. During childhood, he developed medically refractory focal epilepsy from the left hemisphere, requiring epilepsy surgery at age 10. A child presenting with sustained SVT can be at increased risk for intracardiac thrombi and stroke.
Therapy for Stage IV Non–Small-Cell Lung Cancer With Driver Alterations: ASCO and OH (CCO) Joint Guideline Update
Authors: Hanna Nasser H. , Robinson Andrew G. , Temin Sarah , Baker Sherman , Brahmer Julie R. , Ellis Peter M. , Gaspar Laurie E. , Haddad Rami Y. , Hesketh Paul J. , Jain Dharamvir , Jaiyesimi Ishmael , Johnson David H. , Leighl Natasha B. , Moffitt Pamela R. , Phillips Tanyanika , Riely Gregory J. , Rosell Rafael , Schiller Joan H. , Schneider Bryan J. , Singh Navneet , Spigel David R. , Tashbar Joan , Masters Gregory
Published: February 2021

PURPOSE

To provide evidence-based recommendations updating the 2017 ASCO guideline on systemic therapy for patients with stage IV non–small-cell lung cancer (NSCLC) with driver alterations. A guideline update for systemic therapy for patients with stage IV NSCLC without driver alterations was published separately.

METHODS

The American Society of Clinical Oncology and Ontario Health (Cancer Care Ontario) NSCLC Expert Panel updated recommendations based on a systematic review of randomized controlled trials (RCTs) from December 2015 to January 2020 and meeting abstracts from ASCO 2020.

RESULTS

This guideline update reflects changes in evidence since the previous update. Twenty-seven RCTs, 26 observational studies, and one meta-analysis provide the evidence base (total 54). Outcomes of interest included efficacy and safety. Additional literature suggested by the Expert Panel is discussed.

RECOMMENDATIONS

All patients with nonsquamous NSCLC should have the results of testing for potentially targetable mutations (alterations) before implementing therapy for advanced lung cancer, regardless of smoking status recommendations, when possible, following other existing high-quality testing guidelines. Most patients should receive targeted therapy for these alterations: Targeted therapies against ROS-1 fusions, BRAF V600e mutations, RET fusions, MET exon 14 skipping mutations, and NTRK fusions should be offered to patients, either as initial or second-line therapy when not given in the first-line setting. New or revised recommendations include the following: Osimertinib is the optimal first-line treatment for patients with activating epidermal growth factor receptor mutations (exon 19 deletion, exon 21 L858R, and exon 20 T790M); alectinib or brigatinib is the optimal first-line treatment for patients with anaplastic lymphoma kinase fusions. For the first time, to our knowledge, the guideline includes recommendations regarding RET, MET, and NTRK alterations. Chemotherapy is still an option at most stages. Additional information is available at www.asco.org/thoracic-cancer-guidelines .
Cardiac myosin super relaxation (SRX): a perspective on fundamental biology, human disease and therapeutics
Authors: Schmid Manuel , Toepfer Christopher N.
Published: February 2021

The fundamental basis of muscle contraction ‘the sliding filament model’ (Huxley and Niedergerke, 1954; Huxley and Hanson, 1954) and the ‘swinging, tilting crossbridge-sliding filament mechanism’ (Huxley, 1969; Huxley and Brown, 1967) nucleated a field of research that has unearthed the complex and fascinating role of myosin structure in the regulation of contraction. A recently discovered energy conserving state of myosin termed the super relaxed state (SRX) has been observed in filamentous myosins and is central to modulating force production and energy use within the sarcomere. Modulation of myosin function through SRX is a rapidly developing theme in therapeutic development for both cardiovascular disease and infectious disease. Some 70 years after the first discoveries concerning muscular function, modulation of myosin SRX may bring the first myosin targeted small molecule to the clinic, for treating hypertrophic cardiomyopathy (Olivotto et al., 2020). An often monogenic disease HCM afflicts 1 in 500 individuals, and can cause heart failure and sudden cardiac death. Even as we near therapeutic translation, there remain many questions about the governance of muscle function in human health and disease. With this review, we provide a broad overview of contemporary understanding of myosin SRX, and explore the complexities of targeting this myosin state in human disease.

This article has an associated Future Leaders to Watch interview with the authors of the paper.
Isolation and primary culture of Galleria mellonella hemocytes for infection studies
Authors: Senior Nicola J. , Titball Richard W.
Published: February 2021

Galleria mellonella larvae are increasingly used to study the mechanisms of virulence of microbial pathogens and to assess the efficacy of antimicrobials.  The G. mellonella model can faithfully reproduce many aspects of microbial disease which are seen in mammals, and therefore allows a reduction in the use of mammals. The model is now being widely used by researchers in universities, research institutes and industry. An attraction of the model is the interaction between pathogen and host. Hemocytes are specialised phagocytic cells which resemble neutrophils in mammals and play a major role in the response of the larvae to infection. However, the detailed interactions of hemocytes with pathogens is poorly understood, and is complicated by the presence of different sub-populations of cells. We report here a method for the isolation of hemocytes from Galleria mellonella.  A needle-stick injury of larvae, before harvesting, markedly increased the recovery of hemocytes in the hemolymph. The majority of the hemocytes recovered were granulocyte-like cells. The hemocytes survived for at least 7 days in culture at either 28°C or 37°C. Pre-treatment of larvae with antibiotics did not enhance the survival of the cultured hemocytes. Our studies highlight the importance of including sham injected, rather than un-injected, controls when the G. mellonella model is used to test antimicrobial compounds. Our method will now allow investigations of the interactions of microbial pathogens with insect hemocytes enhancing the value of G. mellonella as an alternative model to replace the use of mammals, and for studies on hemocyte biology.
Analysis of diagnostic product portfolios using the Portfolio-To-Impact modelling tool
Authors: Redard-Jacot Maël , Emperador Devy M. , Junyent Eva , Urdea Mickey , Thayer Rich , Sampath Rangarajan
Published: February 2021

Background: The Portfolio-To-Impact version 2 (P2I v.2) financial forecasting tool estimates funding requirements for development of portfolios of candidate health products (drugs, biologics, vaccines or diagnostics). The assumptions and archetypes relating to diagnostics in P2I v.2 are based on limited data and may not accurately describe research and development costs, timelines and probability of success. This study aimed to revise the P2I v.2 tool by modifying the diagnostic assumptions to improve accuracy of predictions for diagnostic portfolios.

Methods: Data from expert interviews and historical information on development of 26 existing diagnostics were used to determine approximate research and development costs, timelines and probability of success for development of diagnostics, and to revise diagnostic archetypes and development phases. To compare the revised tool with P2I v.2, data on 27 candidates from the Foundation for Innovative New Diagnostics (FIND) tuberculosis and pandemic preparedness portfolios were input into both versions.

Results: The number of diagnostic archetypes increased from two in P2I v.2 to three in the revised tool. Total estimated costs to move the 27 candidates along the pipeline to launch were US$641.62 million with P2I v.2 and US$274.00 million with the revised model. The number of expected launches was 21.65 over five years with P2I v.2 and 11.48 over eight years with the revised model. Development timelines were extended and probability of success was lower with the revised model compared with P2I v.2.

Conclusions: Outputs from the revised tool were in line with expert experience, suggesting that the proposed revisions improve the accuracy of the tool for estimating research and development costs, timelines and probability of success relating to diagnostic portfolios. Additional improvements to the tool could include further refinement of archetypes, incorporation of a measure of potential public health impact, and addition of a commercialization phase for diagnostics.
Comparative cross-sectional assessment of knowledge, attitude and practice among university students and employees towards the use of the microbiology laboratory equipment
Authors: Muzaheed Muzaheed , El-Masry Omar S. , Rabaan Ali A. , Alzahrani Faisal , Alomar Amer , Farooqi Faraz Ahmed
Published: February 2021

Background: Continuous evaluation of students and employee’s knowledge and attitude in clinical laboratories is mandatory to ensure a high level of competency, proper practice and to assess the need for training, which shall be reflected on the quality of laboratory results. The aim of the present study was to evaluate the knowledge, attitude, and practice in microbiology laboratories among employees (at King Fahd Hospital of the University) and clinical laboratory students (at Imam Abdulrahman Bin Faisal University)   

Methods: This was a cross-sectional survey of 30 2nd year students, 26 3rd year students, 24 4th year students in the Clinical Laboratory Sciences department, and 30 employees. Participants completed a survey comprising 30 questions to assess their knowledge and attitude towards the use of equipment and practice in the microbiology laboratory.

Results: The results indicated that there was no significant difference between the average scores of all levels of students regarding their knowledge (p = 0.85, 0.999, and 0.869), attitude (p = 0.883, 0.996, 0.853), and practice (p=0.633, 0.325, 0.858) in the microbiology laboratory. Employees scores (knowledge;5.03±2.646, attitude; 12.03±4.89, and practice; 7.7±6.11) were quite poor, as indicated by the lower average results than that of students (knowledge; 5.65±3.08, attitude; 13.25±5.33, and practice; 13.46±5.7).

Conclusions: It is concluded that the knowledge, attitude, and practice of students and employees in the microbiology laboratory needs to be meticulously monitored and improved to ensure high achievement of learning outcomes and better overall performance in the laboratory. This may be achieved through using frequent quizzes and continuous education programs.
NARROWING OF THE GAAS LED EMISSION SPECTRUM DUE TO THE USE OF THE INP (AG) LIGHT FILTER
Authors: Makarenko F. , Arsent'ev A. , Zolnikov Konstantin
Published: February 2021

АЛ115В LED emission spectrum at currents of 6.3 mA and 56 mA, as well as the emission spectrum using an InP (Ag) light filter at current 56 mA, are studied. A classical approximation of the spontaneous emission spectrum of a straight-band LED is presented (without taking into account the narrowing of the band gap due to the high degree of LED doping). The analytical and experimental widths of the LED band gap are estimated. The transmission spectrum of an InP (Ag) light filter is presented, taking into account reflection losses in the region of fundamental transitions. The spectral dependence (fragment) of the InP absorption coefficient is determined. The error is estimated. It is proposed to use АЛ115В with an InP (Ag) light filter in order to narrow the spectral band of radiation from 53 nm to 34 nm.
DEVELOPMENT OF AN ALGORITHM AND MODEL FOR THE INFORMATION SYSTEM FUNCTIONING FOR A SMALL AGRICULTURAL ENTERPRISE
Authors: Novikova Tatyana , Novikova Tat'yana , Novikov A.
Published: February 2021

Even ten years ago, agro-industrial enterprises were not attractive to investors due to the long payback period and a number of risks. However, with increasing world population and increased consumption, and growing demand for agricultural products that is crucial to the growth of production industries and enterprises makes agriculture attractive for investments. In the context of the dynamic development of the agro-industrial complex, the question arises about the informatization of enterprises that were close to bankruptcy not so long ago, but today are profitable and promising. And if there are powerful software products for large agricultural holdings, then small enterprises in the industry do not have software products that meet their needs. Thus, the proposed algorithm and model formed the basis of the developed software for a small agricultural enterprise.
ORGANIZATION OF TECHNICAL SPECIFICATIONS AND INFORMATION DATA IN 3D MODELS OF SOFTWARE SYSTEMS
Authors: Yurov Aleksey , Sokol'nikov V. , Merem'yanin K.
Published: February 2021

The article discusses issues related to the introduction of additional engineering information into the digital model of the product. It is known that technical conditions and dimensions are an integral part of any drawing, and the expansion of the possibilities for presenting engineering data as part of a digital model allows you to get rid of drawing documents. Most software systems for enterprises use the specified functionality in models, but the transfer of data (models and technical conditions in them) is difficult between systems. An example is exporting data from NX CAD to Solid Works. The proposed solutions in this article make it possible to transfer the technical conditions and the required model by means of a software solution and developed methods based on the functionality of the geometric kernel of Open Cascade.
Constitucionalización de los derechos laborales a través del desarrollo jurisprudencial en el caso de la estabilidad laboral y ocupacional reforzada
Authors: Almanza Junco Javier Eduardo
Published: February 2021

El presente artículo estudia el fenómeno de la constitucionalización de los derechos laborales en el caso puntual del desarrollo y configuración de la denominada figura de la estabilidad laboral reforzada, hoy extendida a estabilidad ocupacional reforzada. Para lo anterior, se identifica justificada la relación que ha tenido esta institución del derecho laboral, derivada del principio constitucional de la estabilidad en el empleo, con la configuración y desarrollo de los distintos fueros laborales de origen normativo y jurisprudencial. En consecuencia, se establece que, sobre la base del desarrollo jurisprudencial de cada uno de los fueros, se ha logrado dotar de eficacia jurídica estas estabilidades laborales y ocupacionales reforzadas. Todo lo anterior ocurre en medio del trasegar histórico de una Corte Constitucional que, desde su creación, cada vez se ha ido afianzado más a la denominada práctica del desarrollo progresivo en materia de derechos fundamentales, cuyo contenido analítico y práctico genera una legitimidad consistente en el resultado institucional, al amparo de la praxis del nuevo constitucionalismo en el marco de los Estados constitucionales de derecho.
Respuestas a la migración venezolana en Bogotá: Un aproximación sub-nacional al fenómeno
Authors: Niño César , Jaramillo Ruiz Felipe
Published: February 2021

Como resultado de un proceso de investigación, el artículo analiza cómo se han construido políticas sub-nacionales para responder al fenómeno migratorio en Bogotá. A partir de los modelos de gestión migratoria y las teorías de “push” (empuje) y “pull” (atracción), el estudio contribuye a entender cómo las autoridades locales adoptan políticas para atender a los flujos migratorios. Así, se argumenta que la Alcaldía de Bogotá ha adoptado un modelo liberal de gestión migratoria que propende por garantizar los derechos de los migrantes venezolanos pero, a la vez, insiste en la importancia de regular su estatus migratorio. Además, desde la Alcaldía, se han implementado medidas que contribuyen a atraer aquellos migrantes que normalicen su situación migratoria y empujar a aquellos que deciden no hacerlo.
Abordaje de la violencia laboral contra las mujeres en la justicia ordinaria laboral argentina
Authors: Lobato Julieta
Published: February 2021

Este trabajo explora los estándares que utiliza la jurisprudencia en casos de violencia laboral contra las mujeres. La tesis principal sostiene que la justicia laboral reproduce dinámicas de dominación sexista, al no adecuar los parámetros de abordaje judicial a los estándares internacionales vigentes en materia de protección de los derechos de las mujeres. Para ello analizaremos una muestra de jurisprudencia de la Cámara Nacional de Apelaciones del Trabajo, en la que atenderemos a dos cuestiones principales: por un lado, a las concepciones de violencia contra las mujeres en los ámbitos del trabajo y, por otro lado, a la configuración del cuadro probatorio y la distribución de las cargas de prueba. Luego, contrastaremos estos hallazgos con los principales aportes del feminismo jurídico y los estándares vigentes en materia de derechos humanos de las mujeres.
Acuerdos internacionales de inversión: Compatibilidades e incompatibilidades en treinta años de control de constitucionalidad
Authors: Pontón Serra Juan Pablo , Prieto-Ríos Enrique
Published: February 2021

Los procesos y tendencias mundiales de liberalización e internacionalización de la economía permearon la adopción de la Constitución Política de 1991. Bajo este contexto, el Estado colombiano adoptó la política, que continúa vigente, de suscribir acuerdos internacionales de inversión con otros Estados con el propósito de promover y atraer inversión extranjera en el país. En la actualidad, el arbitraje inversionista-Estado bajo acuerdos internacionales de inversión atraviesa un movimiento de reforma como resultado de profundos cuestionamientos relativos, entre otros, a la falta de capacidad de balancear la capacidad regulatoria y de política pública de los Estados con los derechos e intereses de los inversionistas. Frente a este panorama, la Corte Constitucional colombiana parece haber reclamado con ímpetu su función de guardiana de la integridad y supremacía de la Constitución respecto de los acuerdos internacionales de inversión. Este artículo analiza las principales características del control de constitucionalidad realizado por la Corte Constitucional de los acuerdos internacionales de inversión suscritos por Colombia desde la década de los noventa y el reciente cambio de jurisprudencia que se produjo con relación a su alcance.
An Ensemble Learning Framework for Model Fitting and Evaluation in Inverse Linear Optimization
Authors: Babier Aaron , Chan Timothy C. Y. , Lee Taewoo , Mahmood Rafid , Terekhov Daria
Published: February 2021

We develop a generalized inverse optimization framework for fitting the cost vector of a single linear optimization problem given multiple observed decisions. This setting is motivated by ensemble learning, where building consensus from base learners can yield better predictions. We unify several models in the inverse optimization literature under a single framework and derive assumption-free and exact solution methods for each one. We extend a goodness-of-fit metric previously introduced for the problem with a single observed decision to this new setting and demonstrate several important properties. Finally, we demonstrate our framework in a novel inverse optimization-driven procedure for automated radiation therapy treatment planning. Here, the inverse optimization model leverages an ensemble of dose predictions from different machine learning models to construct a consensus treatment plan that outperforms baseline methods. The consensus plan yields better trade-offs between the competing clinical criteria used for plan evaluation.
Hedging with an Edge: Parametric Currency Overlay
Authors: Barroso Pedro , Reichenecker Jurij-Andrei , Menichetti Marco J.
Published: February 2021

We propose an optimal currency hedging strategy for global equity investors using currency value, carry, and momentum to proxy for expected currency returns. A benchmark risk constraint ensures the overlay closely mimics a fully hedged portfolio. We compare this with naïve and alternative hedges in a demanding out-of-sample test, with transaction and rebalancing costs and margin requirements. Other hedging methods generally reduce risk but at a cost. Some tend to short currencies with high returns and all incur substantial costs with frictions, mostly margin requirements and equity rebalancing costs. The proposed strategy uses predictable returns to reduce this cost. It produces a statistically significant 17% gain in Sharpe ratio and an annualized Jensen-α of 0.93% versus a fully hedged benchmark. Notably, most of the implementation costs of the strategy would be incurred by the benchmark anyway. This reduces its marginal cost and highlights a specific synergy of integrating hedging with speculation.

This paper was accepted by Gustavo Manso, finance.
Nonparametric Learning Algorithms for Joint Pricing and Inventory Control with Lost Sales and Censored Demand
Authors: Chen Boxiao , Chao Xiuli , Shi Cong
Published: February 2021

We consider a joint pricing and inventory control problem in which the customer’s response to selling price and the demand distribution are not known a priori. Unsatisfied demand is lost and unobserved, and the only available information for decision making is the observed sales data (also known as censored demand). Conventional approaches, such as stochastic approximation, online convex optimization, and continuum-armed bandit algorithms, cannot be employed, because neither the realized values of the profit function nor its derivatives are known. A major challenge of this problem lies in that the estimated profit function constructed from observed sales data is multimodal in price. We develop a nonparametric spline approximation–based learning algorithm. The algorithm separates the planning horizon into a disjoint exploration phase and an exploitation phase. During the exploration phase, a spline approximation of the demand-price function is constructed based on sales data, and then the corresponding surrogate optimization problem is solved on a sparse grid to obtain a pair of recommended price and target inventory level. During the exploitation phase, the algorithm implements the recommended strategies. We establish a (nearly) square-root regret rate, which (almost) matches the theoretical lower bound.
Integrated Periodic Timetabling and Vehicle Circulation Scheduling
Authors: Van Lieshout Rolf N.
Published: February 2021

Periodic timetabling is one of the most well-researched problems in the public transport optimization literature. However, the impact that timetabling has on the number of required vehicles, which directly translates to operator costs, is rarely considered. Therefore, in this paper, we consider the problem of jointly optimizing the timetable and the vehicle circulation schedule, which specifies the cyclic sequences of trips that vehicles perform. In order to obtain high-quality solutions to realistic instances, we improve an earlier proposed formulation by contraction techniques, three new valid inequalities, and symmetry-breaking constraints. Ultimately, this allows us to explore the trade-off between the number of vehicles and the attractiveness of the timetable from the passengers’ perspective. An extensive computational study demonstrates the effectiveness of the improved formulation. Moreover, using this approach, we are able to find timetables requiring substantially fewer vehicles at the cost of minimal increases of the average travel time of passengers.
Exposure of children to television food advertisements: an observational analysis
Authors: Morton Leah , Gee Samantha , Hingston Emma J
Published: February 2021

Television advertisements are a powerful medium by which food companies can influence children's dietary choices. This study aimed to determine the current frequency and nutritional content of food and drink advertisements on popular television channels and ascertain whether this differed depending on the target age-group. In this study, television channels were classified by their stated target age-groups. A total of 96 hours of the most popular television channels from each age category were watched during children's peak viewing times, and food and drink advertisements were nutritionally analysed. Overall, 9.5% of advertisements observed were for food and drink. More food and drink advertisements (P<0.001) and those promoting high in fat, salt or sugar (HFSS) products (P<0.001) were broadcast on channels aimed towards older children. There is an ongoing exposure of children to HFSS products via both adult- and child-targeted television channels. Further efforts are required to limit this.
Retrospectivas etnográficas El Centro Umbandista Reino Da Mata de Montevideo desde la decolonialidad
Authors: Palacio Dahiana Barrales
Published: February 2021

Este artículo problematiza —desde una perspectiva descolonial— la construcción de saberes y prácticas manifestadas en el marco del trabajo de campo etnográfico realizado entre 2015 y 2017 en el Centro Umbandista Reino Da Mata de la ciudad de Montevideo, Uruguay. La necesidad de salir de lacárcel epistemológicase hace evidente al presentar extractos del diario de campo y entrevistas. Permanecer dentro de lacarcel epistemológicaimpidió conocer y visibilizar las múltiples formas de colonialidad que formaban parte de la etnografía. Esas formas de colonialidad —de poder, conocimiento, ser y religión— se manifiestan en la elección, el enfoque y las interpretaciones del tema realizadas sobre las prácticas y creencias de ese centro religioso.

Palabras-chave: colonialidad, epistemología, religión, identidad, Umbandismo
Speed characterization of p-i-n photodiode based on GaSb/GaInAsSb/GaAlAsSb heterostructure with frontal bridge contact at 1.9  µm
Authors: Vlasov Dmitrii , Konovalov Gleb , Andreev Igor , Yakovlev Yury , Voropaev Vasilii , Donodin Aleksandr , Tarabrin Mikhail , Batov Daniil , Kunitsyna Ekaterina , Lazarev Vladimir
Published: February 2021

We report a study of the response function parameters (amplitude and rise/fall time) of a high-speed GaSb/GaInAsSb/GaAlAsSb photodiode operating at 1.9 µm as a function of optical input power and reverse bias voltage. The experimental measurement results yield the optimal pulse energy and optimal reverse bias voltage for the photodiode. The 44 ps minimal rise time of the response function and 3.6 GHz bandwidth are achieved under a 3 V reverse bias voltage and pulse energy in the 0.27–2.5 pJ range.
Multimodal fusion of EEG-fNIRS: a mutual information-based hybrid classification framework
Authors: Deligani Roohollah Jafari , Borgheai Seyyed Bahram , McLinden John , Shahriari Yalda
Published: February 2021

Multimodal data fusion is one of the current primary neuroimaging
research directions to overcome the fundamental limitations of
individual modalities by exploiting complementary information from
different modalities. Electroencephalography (EEG) and functional
near-infrared spectroscopy (fNIRS) are especially compelling
modalities due to their potentially complementary features reflecting
the electro-hemodynamic characteristics of neural responses. However,
the current multimodal studies lack a comprehensive systematic
approach to properly merge the complementary features from their
multimodal data. Identifying a systematic approach to properly fuse
EEG-fNIRS data and exploit their complementary potential is crucial in
improving performance. This paper proposes a framework for classifying
fused EEG-fNIRS data at the feature level, relying on a mutual
information-based feature selection approach with respect to the
complementarity between features. The goal is to optimize the
complementarity, redundancy and relevance between multimodal features
with respect to the class labels as belonging to a pathological
condition or healthy control. Nine amyotrophic lateral sclerosis (ALS)
patients and nine controls underwent multimodal data recording during
a visuo-mental task. Multiple spectral and temporal features were
extracted and fed to a feature selection algorithm followed by a
classifier, which selected the optimized subset of features through a
cross-validation process. The results demonstrated considerably
improved hybrid classification performance compared to the individual
modalities and compared to conventional classification without feature
selection, suggesting a potential efficacy of our proposed framework
for wider neuro-clinical applications.
Tight focusing cylindrical vector beams with fractional order
Authors: Stafeev S. S. , Nalimov A. G. , Zaitsev V. D. , Kotlyar V. V.
Published: February 2021

By simulating tight focusing of vector beams with azimuthal polarization of fractional order

0

<
m
<

1

(

m
=
1

is the azimuthal polarization;

m
=
0

is the linear polarization), it is shown that the shape of the intensity distribution in the focal spot changes from elliptical (

m
=
0

) to round (

m
=
0.5

) and ends with an annular ring (

m
=
1

). The shape of the distribution of the longitudinal component of the Poynting vector (energy flux) in the focal spot changes in a different way: from circular (

m
=
0

) to elliptical (

m
=
0.5

), and it ends in an annular ring (

m
=
1

). The diameter of the focal spot at full width at half-maximum for a beam with azimuthal polarization (

m
=
1

) with an optical vortex of the first order for a numerical aperture

N
A

=
0.95

is 0.46 of the wavelength, and the diameter of the axial energy flux for linearly polarized light (

m
=
0

) is 0.45 of the wavelength. Therefore, the answers to the questions of whether the focal spot is round or elliptical and whether the focal spot is minimal with azimuthal polarization with a vortex or with linear polarization without a vortex depend on whether we are considering the intensity at the focus or the energy flow. In the second simulation, the effect of the deviation of the beam order from

m
=
2

(i.e., the case when the backflow is observed at the center of the focal spot) was investigated. It was shown that for integer values of the beam order, the transverse components of the Poynting vector are equal to zero, but for fractional values, they are not.
Evaluation and suppression of the magnetic-induced Rabi broadening of magnetic-sensitive Ramsey fringes
Authors: Ji Qingchen , Zhao Weijing , Wang Yan , Wei Rong
Published: February 2021

Magnetic-sensitive Ramsey fringes are useful for the magnetic field evaluation of atomic fountain clocks. However, broadening mechanisms affect the visibility of the fringes and limit their application for measurement of the magnetic field. The magnetic-induced Rabi broadening, which comes from the magnetic field inhomogeneity in the microwave cavity of fountain clocks and results in the visibility reduction of the fringes, is demonstrated in this paper. Furthermore, an improved method to shorten the Rabi interaction time is proposed to suppress the broadening effect. Experiments are conducted on the rubidium 87 atomic fountain clock to test the broadening mechanism as well as to demonstrate the effectiveness of the improved method to suppress the broadening effect. As a result, we obtain magnetic-sensitive Ramsey fringes and evaluate the average magnetic field. The second-order Zeeman frequency shift also is evaluated with a fractional frequency shift of

1.295

×

10

−
13

, and a frequency uncertainty of

3

×

10

−
16

.
Terahertz generation in artificial two-dimensional periodically poled lithium niobate
Authors: Avetisyan Yuri H.
Published: February 2021

This report shows that intense multicycle terahertz pulses can be generated in two-dimensional quasi-phase-matching structures formed by placing a binary phase mask in front of the periodically poled lithium niobate crystal. The terahertz wave is emitted perpendicular to the direction of the pump pulse propagation, which is favorable for their independent control. A terahertz peak power of 0.6 MW at a frequency of 0.5 THz is predicted for the crystal at 100 K temperature. The efficiency of the pump-to-terahertz conversion is estimated to be 1.5%, with relatively moderate pump pulse energy of 4 mJ. These results could be further improved by resonance enhancement of the pump intensity in an optical cavity or by a proper choice of the pump pulse format.
What optical fiber modes reveal: group velocity and effective index for external perturbations
Authors: Upendar Swaathi , Schmidt Markus A. , Weiss Thomas
Published: February 2021

Precise control of fiber modes and their dispersion is essential, particularly for fields such as nonlinear frequency conversion or biosensing, both of which often require extensive and time-consuming simulations for design optimization. Here, we develop a first-order perturbation theory for predicting the effective index of bound and leaky fiber modes that is applicable for arbitrary global perturbations as long as the perturbations in the external surrounding are constantly homogeneous and isotropic deviations from the unperturbed fiber. This includes changes not only in permittivity and permeability, but also in wavelength. Thus, we are able to calculate the group velocity solely from the field distributions of the fiber modes at a single wavelength, which therefore allows for large-scale parameter sweeps for accurately managing dispersion. We demonstrate the capabilities of our theory for various trial systems such as step index fibers, photonic crystal fibers, and light cages.
Mitigation of phase noise and Doppler-induced frequency offsets in coherent random amplitude modulated continuous-wave LiDAR
Authors: Spollard James T. , Roberts Lyle E. , Sambridge Callum S. , McKenzie Kirk , Shaddock Daniel A.
Published: February 2021

We present a detailed analysis of techniques to mitigate the effects of phase noise and Doppler-induced frequency offsets in coherent random amplitude modulated continuous-wave (RAMCW) LiDAR. The analysis focuses specifically on a technique which uses coherent dual-quadrature detection to enable a sum of squares calculation to remove the input signal’s dependence on carrier phase and frequency. This increases the correlation bandwidth of the matched-template filter to the bandwidth of the acquisition system, whilst also supporting the simultaneous measurement of relative radial velocity with unambiguous direction-of-travel. A combination of simulations and experiments demonstrate the sum of squares technique’s ability to measure distance with consistently high SNR, more than 15 dB better than alternative techniques whilst operating in the presence of otherwise catastrophic phase noise and large frequency offsets. In principle, the technique is able to mitigate any sources of phase noise and frequency offsets common to the two orthogonal outputs of a coherent dual-quadrature receiver including laser frequency noise, speckle-induced phase noise, and Doppler frequency shifts due to accelerations.
Realization of the unconventional photon blockade based on a three-wave mixing system
Authors: Lin Hongyu , Yang Hui , Wang Xiaoqian , Zhou Yanhui , Yao Zhihai
Published: February 2021

In this paper, the unconventional photon blockade is studied in a three-wave-mixing system with a non-degenerate parametric amplification. A method of only retaining the Fock-state basis in the interference path is used to calculate the optimal analytic conditions of unconventional photon blockade. The numerical results agree well with the analytic conditions, which verifies the validity of this method. Our calculations indicate that the strong photon antibunching can be obtained in the high-frequency mode of the three-wave mixing. And the influence of system parameters on photon blockade is also discussed.
Plasmonic hollow fibers with distributed inner-wall hotspots for direct SERS detection of flowing liquids
Authors: Mu Yunyun , Liu Miao , Li Jiajun , Zhang Xinping
Published: February 2021

Plasmonic hollow fibers are fabricated by coating silver-/ gold-alloyed nanoparticles (Ag-Au-ANPs) onto the inner walls of hollow fibers. In this Letter, the Ag-Au-ANPs were synthesized chemically and dissolved in acetone to prepare a colloidal solution, flowed subsequently through the hollow fiber multiple times so that a thin layer of colloidal Ag-Au-ANPs was produced on the inner wall. Annealing at 400°C enabled melting/aggregation of the metallic nanoparticles and consequent formation of closely arranged plasmonic nanostructures fixed solidly on the inner wall. A surface-enhanced Raman scattering (SERS) mechanism was thus established for the liquids flowing through the hollows. The SERS measurements show an enhancement factor

>

10

4

for such plasmonic hollow fibers in the direct detection of R6G/ethanol solutions. Confinement of the excitation laser energy inside the hollow space represents an additional contribution to the enhancement mechanism. This is a promising design for the direct on-site SERS detection of molecules in flowing liquids with low concentrations.
Single-shot interferometric measurement of cavitation bubble dynamics
Authors: Wilson Bryce G. , Fan Zhenkun , Sreedasyam Rahul , Botvinick Elliot L. , Venugopalan Vasan
Published: February 2021

We demonstrate an interferometric method to provide direct, single-shot measurements of cavitation bubble dynamics with nanoscale spatial and temporal resolution with results that closely match theoretical predictions. Implementation of this method reduces the need for expensive and complex ultra-high speed camera systems for the measurement of single cavitation events. This method can capture dynamics over large time intervals with sub-nanosecond temporal resolution and spatial precision surpassing the optical diffraction limit. We expect this method to have broad utility for examination of cavitation bubble dynamics, as well as for metrology applications such as optorheological materials characterization. This method provides an accurate approach for precise measurement of cavitation bubble dynamics suitable for metrology applications such as optorheological materials characterization.
Multimode fiber enables control of spatial coherence in Fourier-domain full-field optical coherence tomography for in vivo corneal imaging
Authors: Auksorius Egidijus , Borycki Dawid , Wojtkowski Maciej
Published: February 2021

Fourier-domain full-field optical coherence tomography (FD-FF-OCT) has recently emerged as a fast alternative to point-scanning confocal OCT in eye imaging. However, when imaging the cornea with FD-FF-OCT, a spatially coherent laser can focus down on the retina to a spot that exceeds the maximum permissible exposure level. Here we demonstrate that a long multimode fiber with a small core can be used to reduce the spatial coherence of the laser and, thus, enable ultrafast in vivo volumetric imaging of the human cornea without causing risk to the retina.