bluuebunny/crossref_metadata_2025 huggingface dataset:
Sexual and reproductive health needs of young people living with HIV in low- and middle-income countries: a scoping review
Authors: Mkumba Laura S. , Nassali Martha , Benner Jasmine , Ritchwood Tiarney D.
Published: November 2021

Background

Young people living with HIV(YPLWH) in low-and middle-income countries are entering adolescence and young adulthood in significant numbers. The majority of the HIV-related research on these young people has focused on clinical outcomes with less emphasis on their sexual and reproductive health (SRH). There is an increasing awareness of the importance of understanding and addressing their SRH needs, as many are at elevated risk of transmitting HIV to their sexual partners and young women, in particular, are at significant risk for transmitting HIV to their infants. The purpose of this scoping review is to synthesize research investigating the SRH needs of young people living with HIV in low- and middle-income countries.

Methods

We searched electronic databases for studies focusing on young people aged 10–24 years and 27 studies met inclusion criteria.

Results

This review identified four themes characterizing research on SRH among young people living with HIV: knowledge of SRH, access to SRH services, sexual practices, and future family planning and childrearing.

Conclusions

Our findings suggest a need for additional research on comprehensive sexuality education to equip YPLWH with knowledge to facilitate desirable SRH outcomes, interventions on sero-status disclosure and condom use, and health provider capacity to provide SRH services in their pre-existing HIV clinical care.
Clinical features and health-related quality of life in adult patients with mucopolysaccharidosis IVA: the Spanish experience
Authors: Quijada-Fraile Pilar , Arranz Canales Elena , Martín-Hernández Elena , Ballesta-Martínez María Juliana , Guillén-Navarro Encarna , Pintos-Morell Guillem , Moltó-Abad Marc , Moreno-Martínez David , García Morillo Salvador , Blasco-Alonso Javier , Couce María Luz , Gil Sánchez Ricardo , Cortès-Saladelafont Elisenda , López Rodríguez Mónica A. , García-Silva María Teresa , Morales Conejo Montserrat
Published: November 2021

Background

Mucopolysaccharidosis (MPS) IVA or Morquio A syndrome is a progressive and disabling disease characterized by a deficiency of the enzyme N-acetylgalactosamine-6-sulphate sulphatase. Its clinical presentation is very heterogeneous and poorly understood in adults.

The aim of this study was to describe the clinical manifestations of MPS IVA in adult patients in Spain and to assess their health-related quality of life (HRQoL).

Results

Thirty-three patients from nine reference centres participated in the study. The median age was 32 (interquartile range [IQR]: 20.5–40.5) years. The phenotype was classical in 54.5% of patients, intermediate in 33.3% of patients, and non-classical in 12.1% of patients. The most common clinical manifestation was bone dysplasia, with a median height of 118 (IQR: 106–136) cm. Other frequent clinical manifestations were hearing loss (75.7%), ligamentous laxity (72.7%), odontoid dysplasia (69.7%), limb deformities that required orthopaedic aids (mainly hip dysplasia and genu valgus) (63.6%), and corneal clouding (60.6%). In addition, 36.0% of patients had obstructive sleep apnoea/hypopnoea syndrome and 33.3% needed non-invasive ventilation. Cervical surgery and varisation osteotomy were the most common surgical interventions (36.4% each). Almost 80% of patients had mobility problems and 36.4% used a wheelchair at all times. Furthermore, 87.9% needed help with self-care, 33.3% were fully dependent, and 78.8% had some degree of pain. HRQoL according to the health assessment questionnaire was 1.43 (IQR: 1.03–2.00) in patients with the non-classical phenotype, but 2.5 (IQR: 1.68–3.00) in those with the classical phenotype. Seven patients were initiated on enzyme replacement therapy (ERT), but two of them were lost to follow-up. Lung function improved in four patients and slightly worsened in one patient. The distance achieved in the six-minute walk test increased in the four patients who could perform it. HRQoL was better in patients treated with elosulfase alfa, with a median (IQR) of 1.75 (1.25–2.34) versus 2.25 (1.62–3.00) in patients not treated with ERT.

Conclusions

The study provides real-world data on patients with MPS IVA. Limited mobility, difficulties with self-care, dependence, and pain were common, together with poor HRQoL. The severity and heterogeneity of clinical manifestations require the combined efforts of multidisciplinary teams.
Healthworker preparedness for COVID-19 management and implementation experiences: a mixed methods study in Uganda’s refugee-hosting districts
Authors: Seruwagi Gloria , Nakidde Catherine , Otieno Felix , Kayiwa Joshua , Luswata Brian , Lugada Eric , Ochen Eric Awich , Muhangi Denis , Okot Betty , Ddamulira Dunstan , Masaba Andrew , Lawoko Stephen
Published: November 2021

Background

The negative impact of COVID-19 on population health outcomes raises critical questions on health system preparedness and resilience, especially in resource-limited settings. This study examined healthworker preparedness for COVID-19 management and implementation experiences in Uganda’s refugee-hosting districts.

Methods

A cross sectional, mixed-method descriptive study in 17 health facilities in 7 districts from 4 major regions. Total sample size was 485 including > 370 health care workers (HCWs). HCW knowledge, attitude and practices (KAP) was assessed by using a pre-validated questionnaire. The quantitative data was processed and analysed using SPSS 26, and statistical significance assumed at p < 0.05 for all statistical tests. Bloom's cutoff of 80% was used to determine threshold for sufficient knowledge level and practices with scores classified as high (80.0–100.0%), average (60.0–79.0%) and low (≤ 59.0%). HCW implementation experiences and key stakeholder opinions were further explored qualitatively using interviews which were audio-recorded, coded and thematically analysed.

Results

On average 71% of HCWs were knowledgeable on the various aspects of COVID-19, although there is a wide variation in knowledge. Awareness of symptoms ranked highest among 95% (p value < 0.0001) of HCWs while awareness of the criteria for intubation for COVID-19 patients ranked lowest with only 35% (p value < 0.0001). Variations were noted on falsehoods about COVID-19 causes, prevention and treatment across Central (p value < 0.0356) and West Nile (p value < 0.0161) regions. Protective practices include adequate ventilation, virtual meetings and HCW training. Deficient practices were around psychosocial and lifestyle support, remote working and contingency plans for HCW safety. The work environment has immensely changed with increased demands on the amount of work, skills and variation in nature of work. HCWs reported moderate control over their work environment but with a high level of support from supervisors (88%) and colleagues (93%).

Conclusions

HCWs preparedness is inadequate in some aspects. Implementation of healthcare interventions is constrained by the complexity of Uganda’s health system design, top-down approach of the national response to COVID-19 and longstanding health system bottlenecks. We recommend continuous information sharing on COVID-19, a design review with capacity strengthening at all health facility levels and investing in community-facing strategies.
Chlorpromazine induces cytotoxic autophagy in glioblastoma cells via endoplasmic reticulum stress and unfolded protein response
Authors: Matteoni Silvia , Matarrese Paola , Ascione Barbara , Ricci-Vitiani Lucia , Pallini Roberto , Villani Veronica , Pace Andrea , Paggi Marco G. , Abbruzzese Claudia
Published: November 2021

Background

Glioblastoma (GBM; grade IV glioma) is characterized by a very short overall survival time and extremely low 5-year survival rates. We intend to promote experimental and clinical research on rationale and scientifically driven drug repurposing. This may represent a safe and often inexpensive way to propose novel pharmacological approaches to GBM. Our precedent work describes the role of chlorpromazine (CPZ) in hindering malignant features of GBM. Here, we investigate in greater detail the molecular mechanisms at the basis of the effect of CPZ on GBM cells.

Methods

We employed proteomics platforms, i.e., activity-based protein profiling plus mass spectrometry, to identify potential cellular targets of the drug. Then, by means of established molecular and cellular biology techniques, we assessed the effects of this drug on GBM cell metabolic and survival pathways.

Results

The experimental output indicated as putative targets of CPZ several of factors implicated in endoplasmic reticulum (ER) stress, with consequent unfolded protein response (UPR). Such a perturbation culminated in a noticeable reactive oxygen species generation and intense autophagic response that resulted in cytotoxic and abortive effects for six GBM cell lines, three of which growing as neurospheres, while it appeared cytoprotective for the RPE-1 human non-cancer neuro-ectodermal cell line.

Conclusions

This discrepancy could be central in explaining the lethal effects of the drug on GBM cells and the relatively scarce cytotoxicity toward normal tissues attributed to this compound. The data presented here offer support to the multicenter phase II clinical trial we have undertaken, which consists of the addition of CPZ to first-line treatment of GBM patients carrying a hypo- or un-methylated MGMT gene, i.e. those characterized by intrinsic resistance to temozolomide.
Study protocol for an open labelled randomised controlled trial of perioperative oral nutrition supplement in breast and colorectal cancer patients undergoing elective surgery
Authors: Wong T. X. , Chen S. T. , Ong S. H. , Shyam S. , Kandasami P. , Chee W. S. S.
Published: November 2021

Background

While it is well established that perioperative use of oral nutrition supplement (ONS) improves nutrition status among severely malnourished surgical cancer patients, the evidence requires further substantiation for non-severely malnourished patients with cancer. This protocol paper presents the rationale and design of a randomised controlled trial to evaluate the effectiveness of preoperative as well as an extended 90-day postoperative use of ONS on nutritional and clinical outcomes among patients undergoing elective surgery for breast and colorectal cancer.

Methods

Patients with primary breast and colorectal cancer undergoing elective surgery are recruited from two tertiary hospitals. Eligible patients are assigned into one of the three intervention arms: (i) Group SS will receive ONS in addition to their normal diet up to 14 days preoperatively and postoperatively up to discharge; (ii) Group SS-E will receive ONS in addition to their normal diet up to 14 days preoperatively, postoperatively up to discharge and for an extended 90 days after discharge; and (iii) Group DS will receive ONS in addition to their normal diet postoperatively up to discharge from the hospital. The ONS is a standard formula fortified with lactium to aid in sleep for recovery. The primary endpoints include changes in weight, body mass index (BMI), serum albumin and prealbumin levels, while secondary endpoints are body composition (muscle and fat mass), muscle strength (handgrip strength), energy and protein intake, sleep quality, haemoglobin, inflammatory markers (transferrin, high sensitivity C-reactive protein, interleukin-6), stress marker (saliva cortisol), length of hospital stay and postoperative complication rate.

Discussion

This trial is expected to provide evidence on whether perioperative supplementation in breast and colorectal cancer patients presenting with high BMI and not severely malnourished but undergoing the stress of surgery would be beneficial in terms of nutritional and clinical outcomes.

Trial registration

ClinicalTrial.gov NCT04400552. Registered on 22 May 2020, retrospectively registered
Channelized active noise elimination (CANE) for suppressing quantization noise in bitstream modulated transmitter (BMT)
Authors: Zhu Rui , Song Yonghoon , Wang Yuanxun Ethan
Published: November 2021

Bitstream modulated transmitters may offer improved power efficiency and linearity simultaneously in RF power amplifiers. Several modulation techniques including envelop delta-sigma modulation and envelope pulse width modulation have been applied. The out-of-band quantization noise associated with these modulations may be rejected by a high-quality factor output filter, yet the in-band quantization noise needs to be further suppressed to meet the requirement of the emission mask. The proposed channelized active noise elimination technique can offer additional quantization noise suppression through software control without involving a passive filter. The essential concept is based on combining the outputs of multiple channels of Pas that have digitally controlled delays to form a FIR filter in analogue domain. A two-channel and a four-channel GaN power amplifiers are built to demonstrate this noise suppression concept and power combiners based on T-junction with quarter wavelength transmission line are proposed to retain the high power efficiency of the transmitters.
Extensive frontal focused ultrasound mediated blood–brain barrier opening for the treatment of Alzheimer’s disease: a proof-of-concept study
Authors: Park So Hee , Baik Kyoungwon , Jeon Seun , Chang Won Seok , Ye Byoung Seok , Chang Jin Woo
Published: November 2021

Background

Focused ultrasound (FUS)-mediated blood–brain barrier (BBB) opening has shown efficacy in removal of amyloid plaque and improvement of cognitive functions in preclinical studies, but this is rarely reported in clinical studies. This study was conducted to evaluate the safety, feasibility and potential benefits of repeated extensive BBB opening.

Methods

In this open-label, prospective study, six patients with Alzheimer’s disease (AD) were enrolled at Severance Hospital in Korea between August 2020 and September 2020. Five of them completed the study. FUS-mediated BBB opening, targeting the bilateral frontal lobe regions over 20 cm3, was performed twice at three-month intervals. Magnetic resonance imaging, 18F-Florbetaben (FBB) positron emission tomography, Caregiver-Administered Neuropsychiatric Inventory (CGA-NPI) and comprehensive neuropsychological tests were performed before and after the procedures.

Results

FUS targeted a mean volume of 21.1 ± 2.7 cm3 and BBB opening was confirmed at 95.7% ± 9.4% of the targeted volume. The frontal-to-other cortical region FBB standardized uptake value ratio at 3 months after the procedure showed a slight decrease, which was statistically significant, compared to the pre-procedure value (− 1.6%, 0.986 vs1.002, P = 0.043). The CGA-NPI score at 2 weeks after the second procedure significantly decreased compared to baseline (2.2 ± 3.0 vs 8.6 ± 6.0, P = 0.042), but recovered after 3 months (5.2 ± 5.8 vs 8.6 ± 6.0, P = 0.89). No adverse effects were observed.

Conclusions

The repeated and extensive BBB opening in the frontal lobe is safe and feasible for patients with AD. In addition, the BBB opening is potentially beneficial for amyloid removal in AD patients.
Undergraduate psychiatric education: current situation and way forward
Authors: Sampogna Gaia , Elkholy Hussien , Baessler Franziska , Coskun Bulent , Pinto da Costa Mariana , Ramalho Rodrigo , Riese Florian , Fiorillo Andrea
Published: November 2021

Undergraduate psychiatric education is essential for the training of medical students and for their recruitment into psychiatry. A significant shortage of graduates choosing a career in psychiatry has been recently documented, and this trend might have many causes. When medical students have positive experiences of teaching, elective placements and exposure to psychiatric patients, their attitudes towards psychiatry are significantly better. Therefore, there is a need to improve the quality of undergraduate training courses in psychiatry. Innovative teaching strategies are suggested, including the use of movies, virtual reality, simulated patients and multiprofessional training wards.
Integralidade do cuidado de enfermagem do pré-natal ao puerpério
Authors: Ferreira Beatriz Assunção , Da Silva Elizabeth Mesquita , Belarmino Adriano Da Costa , Franco Rosana Gomes de Freitas Menezes , Sombra Isabelle Cordeiro de Nojosa , Freitas Alisson Salatiek Ferreira de
Published: November 2021

Objetivo: compreender a integralidade do cuidado de enfermagem do pré-natal ao puerpério. Método: pesquisa de campo, com abordagem qualitativa, realizada na unidade hospitalar, localizada na região metropolitana de Fortaleza/CE. A coleta de dados ocorreu no período de abril a maio de 2021, com a participação de 26 puérperas. Resultados: a mulher, no tocante à sua integralidade durante o ciclo do pré-natal ao puerpério, obteve um cuidado com o foco biológico, surgindo a família como um apoio para os aspectos emocionais. O enfermeiro é o profissional responsável pela criação da confiabilidade da gestante e família, durante o momento do pré-natal até o puerpério. Conclusão: a integralidade do cuidado desenvolvido pelo enfermeiro encontra desafios relacionados à necessidade de uma visão que contemple o processo saúde-doença que rodeia essa mulher.
Association between media use and poor sleep quality among senior high school students: a cross-sectional study
Authors: Chaveepojnkamjorn Wisit , Srikaew Jutiporn , Satitvipawee Pratana , Pitikultang Supachai , Khampeng Soontaree
Published: November 2021

Background: Poor sleep quality (PSQ) is an increasing health problem among adolescents. Mobile phones and portable media devices have become a part of children’s lives and may affect their sleep duration and quality. This study aimed to explore the prevalence of PSQ and identify the association between media use and PSQ among adolescents studying in high school grades 10-12.

Methods: This cross-sectional study was conducted in central Thailand. A multi-stage sampling technique was used to enroll 777 adolescents from eight schools from August to October 2016. The research instruments comprised factors of demographics and consumption behaviors and the Pittsburgh Sleep Quality Index questionnaire. Multivariable logistic regression was used to calculate adjusted odds ratios (ORadj) and 95% confidence intervals (CI).

Results: Prevalence of PSQ was 56.24%. The study subjects were mostly 16-17 years old (67.82%) and female (70.39%). Multivariable logistic regression, after controlling for possible confounders, revealed an increased odds of PSQ among those who used a social media device (OR=1.34, 95%CI=0.97-1.87), and showed a higher proportion of social media use in the PSQ group.

Conclusion: A surveillance system to detect media use and PSQ should be conducted accompanied by knowledge sharing on media use among parents, teachers and adolescents. To determine causal relationships, further longitudinal studies will be required to test the association between media users and PSQ. This study may also provide some implications for health promotion on sleep quality of senior high school students.
Infection prevention measures and outcomes for surgical patients during a COVID-19 outbreak in a tertiary hospital in Daegu, South Korea: a retrospective observational study
Authors: Kwak Kyung-Hwa , Kim Jay Kyoung , Kwon Ki Tae , Yeo Jinseok
Published: November 2021

Background: The first large coronavirus disease 2019 (COVID-19) outbreak outside China occurred in Daegu. In response, we developed infection prevention measures for surgical patients during the outbreak at our hospital and retrospectively reviewed the outcomes of COVID-19–related surgical patients.Methods: We reviewed the medical records of 118 COVID-19–related surgical patients and monitored their clinical outcomes until March 31, 2021. We also interviewed healthcare workers who participated in their perioperative care at Kyungpook National University Chilgok Hospital. The perioperative management guidelines for COVID-19–related patients were prepared through multidisciplinary discussions, including the infection control department, surgical departments, and anesthesiology department before and during the COVID-19 outbreak.Results: One standard operating room was temporarily converted to a negative-pressure room by increasing the exhaust air volume, creating a relative pressure of −11.3 Pa. The healthcare workers were equipped with personal protective equipment according to the patient's classification of the risk of COVID-19 transmission. The 118 COVID-19–related patients underwent emergent surgery in the negative-pressure room, including three COVID-19–confirmed patients and five COVID-19–exposed patients. Conclusion: All surgeries of the COVID-19–related patients were performed without specific adverse events or perioperative COVID-19 transmission. Our experience setting up a negative-pressure operating room and conservative perioperative protocol to prevent COVID-19 transmission will help plan and execute infection control measures in the future.
Constructing a G2-Smooth Compound Curve Based on Cubic Bezier Segments
Authors: Korotkiy Viktor
Published: November 2021

The theory and practice of forming composite G2-smooth (two-continuously differentiable) curves, used in technical design since the mid-60s of the 20th century, is still not reflected in any way in the curriculum of technical universities or in Russian textbooks in engineering and computer graphics. Meanwhile, such curves are used in modeling a wide variety of geometric objects and physical processes.

The article deals with the problem of constructing a composite G2-smooth curve passing through given points and touching at these points pre-specified straight lines. To solve the problem, cubic Bezier segments are used. The main problem in constructing a smooth compound curve is to ensure the continuity of curvature at the joints of the segments. The article shows that for parametrized cubic curves, this problem is reduced to solving a quadratic equation. A software module has been compiled that allows one to construct a plane G2-smooth curve passing through predetermined points and tangent at these points with predetermined straight lines. The shape of the curve (“completeness” of its segments) is adjusted by the user in the dialog mode of the program module.

Solved the problem of constructing a cubic curve smoothly connecting unconnected Bezier segments. An algorithm for constructing a Bezier segment with given tangents and given curvature at its boundary points is proposed.

Some properties of the cubic Bezier segment are considered. In particular, it was shown that for the case of parallel tangents, the curvature at the end of a segment is determined by the position of only one control point (Theorem 1). Cases are considered when the curvature at the ends of the Bezier segment is equal to zero (Theorem 2).

An approximation of a three-point physical spline is performed using Bezier segments. The approximation error was less than 2%, which is comparable to the error in processing the experimental data.

A method is proposed for modeling a spatial G2-smooth curve passing through points set in advance in space and touching at these points arbitrarily oriented lines in space.

The article is of an educational nature and is intended for an in-depth study of the basics of computational geometry and computer graphics.
The Main Reasons for Poor Assimilation of Descriptive Geometry
Authors: Sal'kov N.
Published: November 2021

Descriptive geometry is the most difficult subject studied by first-year students in technical universities. The paper considers the reasons for poor geometric knowledge among university graduates. It is determined that there are three main objective reasons. 1. Poor geometric training in high school, where they study planimetry and stereometry, but not all the knowledge that future students will need at the university is included for passing the Unified State Exam. Also, in high school, students do not develop the habit of thinking analytically, although when proving geometric theorems, this function has developed greatly. 2. Descriptive geometry has a completely different method, which differs from all the methods of disciplines that are studied at school, is the projection method, which develops spatial imagination. Exactly the method that gives any description in the daily activities of any person and in the work of any engineer. 3. Disadvantages of university textbooks on descriptive geometry. Each section of the textbook on descriptive geometry has been based on a particular geometric image since ancient times: a point, a straight line, a plane, etc. As a result, tasks that could be collected in their own section of the textbook (for example, all positional problems or all metric problems) are scattered throughout the entire body of the textbook. And from this there is an opinion that each of the tasks has its own unique solution algorithm. It is shown that with a systematic approach, all positional problems, as well as all metric ones, are solved, in principle, according to a single algorithm.
Augmented Reality in Conducting Classes in Engineering and Technical Disciplines of Design
Authors: Musaeva Tatiana , Urago A.
Published: November 2021

The article discusses the issue of increasing the efficiency of the educational process in engineering technical disciplines, in the study of which students acquire professional competencies in the design of industrial products. There are a number of problems when solving problems in which it is necessary to create drawings of realistic physical objects under study, as well as the correct representation of the 2D image format in 3D format. As a result, when mentally projecting a product onto different projection planes, typical errors occur. These errors are associated with human cognitive spatial reasoning abilities, as confirmed and described by experts in this subject area.

In the article, in order to solve the indicated problem, it is proposed to create and introduce modern digital technologies of virtual and augmented reality into the educational process. The proposed technologies do not replace the teacher, but are considered only as additional means that will make it possible to more clearly and qualitatively disclose the thematic units of the discipline, which will help the student in mastering the material necessary for acquiring professional competencies.

The process of creating a course requires solving a wide range of problems:

1. research of the possibilities of technologies and means of augmented reality;

2. selection and substantiation of the composition of technical means necessary in the process of studying theoretical material and performing practical tasks in the augmented reality environment;

3. creating an architecture of a model of interaction between a teacher and a student when studying a theoretical block of a discipline;

4. creating the architecture of the model of interaction between the teacher and the student when studying the practical block of the discipline;

5. development of the course structure;

6. development of a methodology for studying the discipline "Engineering and Computer Graphics" in the environment of augmented reality;

7. creation of a library of virtual objects of industrial products.

The article briefly discusses only a part of the listed issues, namely 1 - 4.
La vigencia del modelo de propaganda de Herman y Chomsky en las protestas en Ecuador de octubre de 2019
Authors: Casado Gutiérrez Fernando
Published: November 2021

El Modelo de Propaganda (MP) diseñado por Herman y Chomsky en 1988, en su obra los Guardianes de la Libertad, sigue contando con detractores y seguidores. Este modelo centrado en el comportamiento y actuación de los medios (Herman, 2000), critica frontalmente la ideología liberal y los intereses de las élites, lo que le situó en la periferia de los debates académicos. No obstante, a partir del nuevo siglo, algunos autores han profundizado a nivel teórico y práctico el MP (PedroCarañana, Boudry, Klaehn). Nuestra investigación pretende demostrar la actualidad del modelo a través del análisis (cuantitativo y cualitativo) de la cobertura y posicionamiento de los principales medios ecuatorianos de las protestas contra los planes de ajuste económico impuestos por el llamado decreto 883 que en octubre del año 2019 liberó el precio de los combustibles en Ecuador.
Optimal Power Flow in Distribution Networks Under N – 1 Disruptions: A Multistage Stochastic Programming Approach
Authors: Yang Haoxiang , Nagarajan Harsha
Published: November 2021

Contingency research to find optimal operations and postcontingency recovery plans in distribution networks has gained major attention in recent years. To this end, we consider a multiperiod optimal power flow problem in distribution networks, subject to the N – 1 contingency in which a line or distributed energy resource fails. The contingency can be modeled as a stochastic disruption, an event with random magnitude and timing. Assuming a specific recovery time, we formulate a multistage stochastic convex program and develop a decomposition algorithm based on stochastic dual dynamic programming. Realistic modeling features, such as linearized AC power flow physics, engineering limits, and battery devices with realistic efficiency curves, are incorporated. We present extensive computational tests to show the efficiency of our decomposition algorithm and out-of-samplex performance of our solution compared with its deterministic counterpart. Operational insights on battery utilization, component hardening, and length of recovery phase are obtained by performing analyses from stochastic disruption-aware solutions.

Summary of Contribution: Stochastic disruptions are random in time and can significantly alter the operating status of a distribution power network. Most of the previous research focuses on the magnitude aspect with a fixed set of time points in which randomness is observed. Our paper provides a novel multistage stochastic programming model for stochastic disruptions, considering both the uncertainty in timing and magnitude. We propose a computationally efficient cutting-plane method to solve this large-scale model and prove the theoretical convergence of such a decomposition algorithm. We present computational results to substantiate and demonstrate the theoretical convergence and provide operational insights into how making infrastructure investments can hedge against stochastic disruptions via sensitivity analyses.
Skill Acquisition and Data Sales
Authors: Huang Shiyang , Xiong Yan , Yang Liyan
Published: November 2021

We develop a data-sales model to study the implications of alternative data for financial markets. Investors acquire skills to process the purchased raw data, and developing such skills is costly and involves considerable uncertainty. The data vendor controls the size of the data sample to influence the precision of the information investors can extract from the purchased data. Price informativeness is hump-shaped in skill-acquisition costs although the cost of capital and return volatility are U-shaped in skill-acquisition costs. Similar patterns can arise for skill mean and volatility. Our analysis suggests that the funds and data industries foster each other.

This paper was accepted by Agostino Capponi, finance.
Good to Go First? Position Effects in Expert Evaluation of Early-Stage Ventures
Authors: Bian Jiang , Greenberg Jason , Li Jizhen , Wang Yanbo
Published: November 2021

There is often considerable anxiety and conflicting advice concerning the benefits of presenting/being evaluated first. We thus investigate how expert evaluators vary in their evaluations of entrepreneurial proposals based upon the order in which they are evaluated. Our research setting is a premiere innovation fund competition in Beijing, China, where the prize money at stake is economically meaningful, and evaluators are quasi-randomly assigned to evaluate written grant proposals without the possibility of peer influence. This enables us to credibly recover a causal position effect. We also theorize and test how heterogeneity in evaluators’ prior (context-specific) judging experience moderates position effects. Overall, we find that a proposal evaluated first requires total assets in the top 10th percentile to merely equal the evaluation of a proposal in the bottom 10th percentile that is not evaluated first. Firm and evaluator fixed-effects models yield consistent findings. We consider evaluation design elements that may mollify these position effects in the discussion section.

This paper was accepted by Sridhar Tayur, entrepreneurship and innovation.
Auctioning IT Contracts with Renegotiable Scope
Authors: Huang He , Li Zhipeng , Liu De , Xu Hongyan
Published: November 2021

Motivated by challenges facing IT procurement, this paper studies a hybrid procurement model in which a reverse auction of a fixed-price IT outsourcing contract may be followed by renegotiation to extend the contract’s scope. In this model, the buyer balances the needs to incentivize noncontractible vendor investment and to curb the winning vendor’s information rent by choosing the initial project scope and the buyer’s investment in the quality of the project. We find that a buyer may benefit from inducing ex post renegotiation to motivate vendor investment, especially when the winning vendor has high bargaining power and the quality uncertainty is low. Broadening the initial scope reduces information rent but leaves little room for ex post renegotiation and, hence, discourages vendor investment, whereas increasing the buyer’s investment has opposite effects. Interestingly, the two measures can be strategic substitutes or complements depending on the likelihood of the renegotiation and the two parties’ bargaining powers. The buyer may strategically set a low initial project scope and high investment to incentivize renegotiation and vendor investment, which may explain why many IT outsourcing projects start small and allow expansions. Our findings also generate several testable predictions for IT outsourcing.

This paper was accepted by Kartik Hosanagar, information systems.
Efficient Allocations in Double Auction Markets
Authors: Pennanen Teemu
Published: November 2021

This paper proposes a simple descriptive model of discrete-time double auction markets for divisible assets. As in the classical models of exchange economies, we consider a finite set of agents described by their initial endowments and preferences. Instead of the classical Walrasian-type market models, however, we assume that all trades take place in a centralized double auction where the agents communicate through sealed limit orders for buying and selling. We find that, under nonstrategic bidding, double auction clears with zero trades precisely when the agents’ current holdings are on the Pareto frontier. More interestingly, the double auctions implement Adam Smith’s “invisible hand” in the sense that, when starting from disequilibrium, repeated double auctions lead to a sequence of allocations that converges to individually rational Pareto allocations.
Dynamic Learning and Market Making in Spread Betting Markets with Informed Bettors
Authors: Birge John R. , Feng Yifan , Keskin N. Bora , Schultz Adam
Published: November 2021

How Bookies Can Outwit Sophisticated Bettors

Sports-betting markets are based entirely on predictions. A bettor has to pick a winning contestant, and a market maker―a bookie―bets on the opponent. As bookies have to take the other side of every bet, it is of great value to understand the market making problem, that is, how to set the spread lines as “prices” for the bookies. Nevertheless, understanding of this problem is limited. Specifically, sophisticated bettors exist in the market, and a bookie can be manipulated by skillful bettors because of information asymmetry. In “Dynamic Learning and Market Making in Spread Betting Markets with Informed Bettors,” Birge, Feng, Keskin, and Schultz study the market-making problem under information asymmetry and market manipulation. They show that, although many popular learning and pricing algorithms, such as Bayesian policies, are effective in learning, they are vulnerable to strategic manipulations. The authors propose a dynamic learning and pricing algorithm, called the inertial policy, that collects information from the market effectively but also protects the bookie from strategic manipulations.
Using ℓ1-Relaxation and Integer Programming to Obtain Dual Bounds for Sparse PCA
Authors: Dey Santanu S. , Mazumder Rahul , Wang Guanyi
Published: November 2021

Dual Bounds of Sparse Principal Component Analysis

Sparse principal component analysis (PCA) is a widely used dimensionality reduction tool in machine learning and statistics. Compared with PCA, sparse PCA enhances the interpretability by incorporating a sparsity constraint. However, unlike PCA, conventional heuristics for sparse PCA cannot guarantee the qualities of obtained primal feasible solutions via associated dual bounds in a tractable fashion without underlying statistical assumptions. In “Using L1-Relaxation and Integer Programming to Obtain Dual Bounds for Sparse PCA,” Santanu S. Dey, Rahul Mazumder, and Guanyi Wang present a convex integer programming (IP) framework of sparse PCA to derive dual bounds. They show the worst-case results on the quality of the dual bounds provided by the convex IP. Moreover, the authors empirically illustrate that the proposed convex IP framework outperforms existing sparse PCA methods of finding dual bounds.
Building an Equilibrium: Rules vs. Principles in Relational Contracts
Authors: Gibbons Robert , Grieder Manuel , Herz Holger , Zehnder Christian
Published: November 2021

Effective collaboration within and between organizations requires efficient adaptation to unforeseen change. We study how parties build relational contracts that achieve this goal. We focus on the “clarity problem”—whether parties have a shared understanding of the promises they make to each other. Specifically, (a) a buyer and seller play a trading game in several periods; (b) they know their environment will change but do not know how; and (c) before any trading occurs, they can reach a nonbinding agreement about how to play the entire game. We hypothesize that pairs whose initial agreement defines a broad principle rather than a narrow rule are more successful in solving the clarity problem and in achieving efficient adaptation after unforeseen change. In our baseline condition, we indeed observe that pairs who articulate principles achieve significantly higher performance after change occurred. Underlying this correlation, we also find that pairs with principle-based agreements were more likely to both expect and take actions that were consistent with what their agreement prescribed. To investigate a causal link between principle-based agreements and performance, we implement a “nudge” intervention that induces more pairs to articulate principles. The intervention succeeds in coordinating more pairs on efficient quality immediately after the unforeseen change, but it fails to coordinate expectations on price, ultimately leading to conflicts and preventing an increase in long-run performance after the shock. Our results suggest that (1) principle-based agreements may improve organizational performance but (2) high-performing relational contracts may be difficult to build.

History: This paper has been accepted for the Organization Science Special Issue on Experiments in Organizational Theory.

Funding: We gratefully acknowledge financial support from the Massachusetts Institute of Technology Sloan School's Program on Innovation in Markets and Organizations.

Supplemental Material: The online appendix is available at https://doi.org/10.1287/orsc.2021.1503 .
A review of mitochondrial disease in dogs
Authors: Gomes Sérgio
Published: November 2021

Mitochondria are maternally inherited cellular organelles located in the cytoplasm of most eukaryotic cells. Mitochondrial diseases are a type of metabolic disorder, involving the respiratory chain under the control of both the mitochondrial DNA and nuclear DNA. In dogs, mitochondriopathies are considered rare, with few clinical syndromes having had their structural, biochemical and genetic basis identified. In this review, the basis for suspecting a mitochondrial disease clinically is summarised, with particular focus on mitochondrial encephalopathies, encephalomyelopathies and neuropathies. Recognisable confirmed mitochondriopathies including spongiform leukoencephalomyelopathy, Alaskan Husky encephalopathy, Leigh-like subacute necrotising encephalopathy and sensory ataxic neuropathy in the Golden Retriever are described in detail, alongside previously reported individual cases of presumptive mitochondriopathies of unknown origin. Genetic mutations reported in the literature are reviewed. A clear classification for mitochondrial diseases in veterinary medicine is lacking, and this review is the first to address this class of diseases specifically in dogs.
A review of ocularEncephalitozoon cuniculiinfection in the rabbit
Authors: Baney Victoria , Blacklock Ben , Keeble Emma
Published: November 2021

Encephalitozoon cuniculi is a microsporidian parasite affecting rabbits and other mammals, including immunocompromised humans. One clinical manifestation of E. cuniculi is the ocular form, which typically presents with phacoclastic uveitis, a yellow-white granuloma and a cataract. This literature review focuses on the aetiopathogenesis, presentation, diagnosis and treatment options for ocular E. cuniculi with emphasis on phacoemulsification, the gold standard treatment.
Focus stacking and 3D visualization in multispectral microscopy of thick samples
Authors: Alonso Julia R. , Silva Alejandro , Fernández Ariel , Arocena Miguel
Published: November 2021

A custom built fluorescence microscope with an electrically tunable lens is used to acquire multi-focus z-stacks of thick biological samples under multispectral illumination. Acquired information allows for 3D visualization of the sample after stack processing.
Enabling Next-generation Holographic Displays with Artificial Intelligence
Authors: Wetzstein Gordon , Peng Yifan , Choi Suyeon , Kim Jonghyun
Published: November 2021

We discuss recent advances of computer-generated holographic display systems that incorporate artificial intelligence to achieve unprecedented holographic image fidelity and real-time framerates.
Focal Flow Based Depth Reconstruction from Focal Stack
Authors: Deng Xiaojuan , Chen Huazhen , Liu Chang , Qiu Jun
Published: November 2021

In this paper, focal flow based depth reconstruction method is proposed to reduce the error caused by magnification of perspective and improve the depth accuracy of weak texture regions.
High dynamic range 3D measurement based on space-time speckle correlation and color multiplexing
Authors: Li Tong , Zhang Shaohui , Hu Yao , Hao Qun
Published: November 2021

In this paper, we propose a strategy to expand the measurement dynamic range taking advantage of color multiplexing speckle projection and space-time speckle correlation.
Defending deep neural networks from adversarial attacks on three-dimensional images by compressive sensing
Authors: Kravets Vladislav , Javidi Bahram , Stern Adrian
Published: November 2021

We demonstrate the utility of compressive sensing to defend against adversarial attacks on deep learning classifiers and to encrypt the 3D image, thus, to avoid counterattacks.
Single-shot 5D imaging at 100 billion frames per second using stereo-polarimetric compressed ultrafast photography
Authors: Liang Jinyang , Wang Peng , Zhu Liren , Wang Lihong V.
Published: November 2021

Stereo-polarimetric compressed ultrafast photography is developed and applied to 3D ultrafast imaging of the linear polarization properties of a single ultrashort laser pulse propagating in a scattering medium at 100 billion frames per second.
Three-Dimensional Localization Microscopy by Deep Learning
Authors: Nehme Elias , Ferdman Boris , Freedman Daniel , Weiss Lucien E. , Gordon-Soffer Racheli , Naor Tal , Kedem Reut Orange , Alalouf Onit , Michaeli Tomer , Shechtman Yoav
Published: November 2021

In this talk I will describe how joint optimization of the microscope’s point-spread-function alongside the image processing algorithm, both using neural nets, enables dense emitter fitting for super-resolution microscopy and other challenging volumetric microscopy applications.
In-line monitoring of ceramic resins used in stereolithography via high-frequency dielectric analysis
Authors: Zakeri Setareh , Järveläinen Matti , Levänen Erkki
Published: November 2021

Collo technology measures electromagnetic features of liquids i.e. reacting to physical and chemical changes in liquids. In this research, we investigate the possibilities to monitor the photocuring behavior of ceramic resins used in stereolithography using Collo.
Optical diffraction tomography with isotropic resolution based on tomographic mold for optical trapping
Authors: Lee Moosung , Kim Kyoohyun , Oh Jeonghun , Park YongKeun
Published: November 2021

We demonstrate a non-invasive approach for rotating a sample with the molded dynamic light trap, which enables label-free 3D quantitative phase imaging of microscopic samples with isotropic resolution.
Realization of low-crosstalk hollow-core photonic-crystal fiber resonator based on polarization-correlated phase modulation
Authors: Jiao Hongchen , Wang Tao , Liu Jie , Gao Heli , Feng Lishuang , Ma Honghao
Published: November 2021

The low-crosstalk coupling based on polarization-correlated phase modulation was proposed, where the polarization extinction ratio could be decoupled from the polarization- correlated phase. A hollow-core photonic-crystal fiber resonator with crosstalk lower than -20dB was realized.
Analysis of Optical Characteristics of the Photopolymer for a Full-Color Holographic Optical Element
Authors: Wu Hui-Ying , Shin Chang-Won , Alam Md. Shahinur , Nam Oh-Seung , Jeon Seok-Hee , Kim Nam
Published: November 2021

The optical characteristics of the photopolymer were analyzed to manufacture the reflection-type full-color holographic optical element (HOE) with uniform diffraction efficiency. Preliminary experimental results confirm that controlling the initial exposure time of three lasers can implement high-efficiency full-color HOE.
Integrated Optical Directional Coupler based Refractive Index Sensor
Authors: Bawa Garima , Saha Nabarun , Tripathi Saurabh Mani
Published: November 2021

We present a highly sensitive and narrow bandwidth refractive index sensor, based on an integrated silicon-on-silica strip waveguide directional coupler. The optimization of geometric parameters have been presented to achieve a sensitivity of 367 μm/RIU.
Fast 3D measurement method based on improved digital image correlation using grid-based feature extraction
Authors: Chen Juntong , Yin Wei , Zuo Chao , Feng Shijie
Published: November 2021

In this paper, we propose an enhanced IC-GN algorithm that selects multiple seed points based on the grid to facilitate parallel processing of global points, enabling highly accurate 3D measurements with high computational efficiency.
Single-shot, 360-degree, and high-precision three- dimensional shape measurement for human heads based on digital image correlation and plane mirrors
Authors: Liu Shaogang , Zhang Yuzhen , Yin Wei , Zuo Chao
Published: November 2021

This paper presents a single-shot, 360-degree, and high-precision three-dimensional shape measurement for human heads based on digital image correlation and plane mirrors, which improves the matching speed of DIC by introducing multiple threads.
Defect localization in noisy fringe patterns using subspace method and naive Bayes classifier
Authors: Ramaiah Jagadesh , Gannavarpu Rajshekhar
Published: November 2021

Here, we present an effective defect identification method using phase deriva- tives as feature vectors and a naive Bayes classifier to predict defective pixels. Simulation results are shown to illustrate the performance of the proposed method.