bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

Abstract
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.
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.
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.
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.
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.
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 .
Plasmonic tapered-fiber interference sensor for simultaneously detecting refractive index and temperature
Authors: Chen Xinghong , Li Xuejin , Yi Duo , Hong Xueming , Chen Yuzhi 
Published: November 2021

A single-optic-fiber sensor is proposed to simultaneously detect the refractive index (RI) and temperature (T) at a single wavelength band. This sensor is based on the mixed effects of Mach–Zehnder interference (MZI) and surface plasmon resonance (SPR), where MZI is excited by a tapered-fiber structure, and SPR is stimulated by a 45 nm gold film on the tapered-fiber surface. The detection signal of an SPR spectrum superimposed on interference stripes was obtained. After fast Fourier transform and filter processing, the MZI and SPR signals were separated. Experimental results indicate that our sensor can improve the RI sensitivity to 2021.07 nm/RIU (21-fold greater than that of the original tapered-fiber MZI sensor) and detect T simultaneously. Additionally, this highly integrated sensor simplifies the detection system, with potential applications in portable biochemical sensing.
Extending the L-band amplification to 1623  nm using Er/Yb/P co-doped phosphosilicate fiber
Authors: Chen Yang , Lou Yang , Gu Zhimu , Qiu Qiang , He Le , Li Wenzhen , Yin Xiaoke , Zhao Xinyue , Liu Shaokun , Peng Jinggang , Li Haiqing , Xing Yingbin , Chu Yingbo , Dai Nengli , Li Jinyan 
Published: November 2021

The gain bandwidth of the erbium-doped fiber amplifier limits the enhancement of the transmission capacity in optical fiber communication systems. This Letter reports an erbium-ytterbium co-doped phosphosilicate fiber, which is expected to increase transmission capacity by extending the L-band gain bandwidth to 1623 nm. The fiber was fabricated by modified chemical vapor deposition combined with solution doping technology. The mechanism of bandwidth-expansion by inhibiting the signal excited-state absorption was investigated. When the signal power and pump power were maintained at

−

3.7

d
B
m

and

∼

720

m
W

at 1480 nm, the 20 dB gain range was extended out to 1623 nm. Additionally, the noise figure at 1623 nm decreased to 6.01 dB, with 23 dBm saturated output power. The results show that the erbium-ytterbium co-doped phosphosilicate fiber has a great potential for extending L-band amplification.
Determinants of improvement trends in health workers’ compliance with outpatient malaria case-management guidelines at health facilities with available “test and treat” commodities in Kenya
Authors: Amboko Beatrice , Stepniewska Kasia , Malla Lucas , Machini Beatrice , Bejon Philip , Snow Robert W. , Zurovac Dejan 
Published: November 2021

Background
Health workers’ compliance with outpatient malaria case-management guidelines has been improving in Africa. This study examined the factors associated with the improvements.

Methods
Data from 11 national, cross-sectional health facility surveys undertaken from 2010–2016 were analysed. Association between 31 determinants and improvement trends in five outpatient compliance outcomes were examined using interactions between each determinant and time in multilevel logistic regression models and reported as an adjusted odds ratio of annual trends (T-aOR).

Results
Among 9,173 febrile patients seen at 1,208 health facilities and by 1,538 health workers, a higher annual improvement trend in composite “test and treat” performance was associated with malaria endemicity-lake endemic (T-aOR = 1.67 annually; p<0.001) and highland epidemic (T-aOR = 1.35; p<0.001) zones compared to low-risk zone; with facilities stocking rapid diagnostic tests only (T-aOR = 1.49; p<0.001) compared to microscopy only services; with faith-based/non-governmental facilities compared to government-owned (T-aOR = 1.15; p = 0.036); with a daily caseload of >25 febrile patients (T-aOR = 1.46; p = 0.003); and with under-five children compared to older patients (T-aOR = 1.07; p = 0.013). Other factors associated with the improvement trends in the “test and treat” policy components and artemether-lumefantrine administration at the facility included the absence of previous RDT stock-outs, community health workers dispensing drugs, access to malaria case-management and Integrated Management of Childhood Illness (IMCI) guidelines, health workers’ gender, correct health workers’ knowledge about the targeted malaria treatment policy, and patients’ main complaint of fever. The odds of compliance at the baseline were variable for some of the factors.

Conclusions
Targeting of low malaria risk areas, low caseload facilities, male and government health workers, continuous availability of RDTs, improving health workers’ knowledge about the policy considering age and fever, and dissemination of guidelines might improve compliance with malaria guidelines. For prompt treatment and administration of the first artemether-lumefantrine dose at the facility, task-shifting duties to community health workers can be considered.