bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Passive Flow Control Devices on Base Pressure for Mach Numbers Between 0.5 and 1.4
Authors: Murugan Jayaprakash N. , Chutkey Kiran , Sri Raghu R. , Verma Shashi B.
Published: July 2021

Experimental studies are carried out on an axisymmetric cylindrical base body for six freestream Mach numbers between 0.54 and 1.41. Unsteady pressure is measured on the base surface using high-frequency response Kulite pressure transducers. The effect of passive flow control devices on the mean base pressure and the unsteady characteristics of base pressure have been studied. A blunt base, a conventional cavity device, and three different ventilated cavity devices have been tested along with four different rounded base lip devices. A total of 20 different base geometric modifications are tested at 6 freestream Mach numbers resulting in 120 test cases. The cavity devices improve the base pressure as compared to the blunt base case, particularly for freestream Mach numbers more than 0.98. Among all the cases considered, a maximum increase of 8.6% in the base pressure coefficient is noticed for the normal ventilated cavity device as compared to the blunt base case for freestream Mach number of 1.22. The power spectral density of base pressure fluctuations revealed the dominant peaks on the base surface. The Strouhal number associated with the coherent structures developing in the shear layer varies between 0.2 and 0.27 for the six freestream Mach numbers considered. In the presence of cavity devices, dominant peaks are observed for Strouhal numbers between 1 and 5. The root-mean-square, skewness, kurtosis of the base pressure fluctuations for all the cases are presented. Maximum reduction in base pressure fluctuation is observed for the normal and inclined ventilated cavity device configuration test cases.
Storywrangler: A massive exploratorium for sociolinguistic, cultural, socioeconomic, and political timelines using Twitter
Authors: Alshaabi Thayer , Adams Jane L. , Arnold Michael V. , Minot Joshua R. , Dewhurst David R. , Reagan Andrew J. , Danforth Christopher M. , Dodds Peter Sheridan
Published: July 2021

We present Storywrangler, an interactive cultural exploratorium of phrase popularity using 100 billion tweets in 100 languages.
Supplemental Material: Latest Quaternary slip rates of the San Bernardino strand of the San Andreas fault, southern California, from Cajon Creek to Badger Canyon
Authors: McGill S.F. , al. et
Published: July 2021

Additional details on methods and for descriptions and interpretations of geologic units at the Badger Canyon site. Additional trench logs and photographs showing locations of dated samples that were not shown in other figures. Tables providing latitude and longitude for all dated samples, as well as field and lab data for terrestrial nuclide dating and complete soil descriptions.
Survival in colon and rectal cancers in Finland and Sweden through 50 years
Authors: Hemminki Kari , Försti Asta , Hemminki Akseli
Published: July 2021

Objectives

Global survival studies have shown favourable development in colon and rectal cancers but few studies have considered extended periods or covered populations for which medical care is essentially free of charge.

Design

We analysed colon and rectal cancer survival in Finland and Sweden over a 50-year period (1967–2016) using data from the Nordcan database. In addition to the standard 1-year and 5-year survival rates, we calculated the difference between these as a novel measure of how well survival was maintained between years 1 and 5.

Results

Relative 1-year and 5-year survival rates have developed favourably without major shifts for men and women in both countries. For Finnish men, 1-year survival in colon cancer increased from 50% to 82%, and for rectal cancer from 62% to 85%. The Swedish survival was a few per cent unit better for 1-year survival but for 5-year survival the results were equal. Survival of female patients for both cancers was somewhat better than survival in men through 50 years. Overall the survival gains were higher in the early compared with the late follow-up periods, and were the smallest in the last 10 years. The difference between 1-year and 5-year survival in colon cancer was essentially unchanged over the 50-year period while in rectal cancer there was a large improvement.

Conclusions

The gradual positive development in survival suggests a contribution by many small improvements rather than single breakthroughs. The improvement in 5-year survival in colon cancer was almost entirely driven by improvement in 1-year survival while in rectal cancer the positive development extended to survival past year 1, probably due to successful curative treatments. The current challenges are to reinvigorate the apparently stalled positive development and to extend them to old patients. For colon cancer, survival gains need to be extended past year 1 of diagnosis.
Clinical decision support system to optimise symptom management in palliative medicine: focus group study
Authors: van der Stap Lotte , de Heij Albert H , van der Heide Agnes , Reyners Anna KL , van der Linden Yvette M
Published: July 2021

Objectives

Suboptimal symptom control in patients with life-limiting illnesses is a major issue. A clinical decision support system (CDSS) that combines a patient-reported symptom assessment scale (SAS) and guideline-based individualised recommendations has the potential to improve symptom management. However, lacking end-user acceptance often prevents CDSS use in daily practice.

We aimed to evaluate the acceptability and feasibility of a palliative care CDSS according to its targeted end-users.

Methods

Six focus groups with different groups of stakeholders were conducted: (1) patient representatives; (2) community nurses; (3) hospital nurses; (4) general practitioners; (5) hospital physicians and (6) palliative care specialists. Audiotapes were transcribed verbatim and thematically analysed.

Results

Fifty-one stakeholders (6–12 per focus group) participated. Six themes were discussed: effect, validity, continuity, practical usability, implementation and additional features. All participants expected a CDSS to improve symptom management, for example, by reminding clinicians of blind spots and prompting patient participation. They feared interference with professional autonomy of physicians, doubted the validity of using a patient-reported SAS as CDSS input and thought lacking care continuity would complicate CDSS use. Clinicians needed clear criteria for when to use the CDSS (eg, life-limiting illness, timing in illness trajectory). Participants preferred a patient-coordinated system but were simultaneously concerned patients may be unwilling or unable to fill out an SAS.

Conclusions

A palliative care CDSS was considered useful for improving symptom management. To develop a feasible system, barriers for successful implementation must be addressed including concerns about using a patient-reported SAS, lacking care continuity and unclear indications for use.
Immunogenomic determinants of tumor microenvironment correlate with superior survival in high-risk neuroblastoma
Authors: Bao Riyue , Spranger Stefani , Hernandez Kyle , Zha Yuanyuan , Pytel Peter , Luke Jason J , Gajewski Thomas F , Volchenboum Samuel L , Cohn Susan L , Desai Ami V
Published: July 2021

Background

Tumor-infiltrating CD8+ T cells and neoantigens are predictors of a favorable prognosis and response to immunotherapy with checkpoint inhibitors in many types of adult cancer, but little is known about their role in pediatric malignancies. Here, we analyzed the prognostic strength of T cell-inflamed gene expression and neoantigen load in high-risk neuroblastoma. We also compared transcriptional programs in T cell-inflamed and non-T cell-inflamed high-risk neuroblastomas to investigate possible mechanisms of immune exclusion.

Methods

A defined T cell-inflamed gene expression signature was used to categorize high-risk neuroblastomas in the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) program (n=123), and the Gabriella Miller Kids First (GMKF) program (n=48) into T cell-inflamed, non-T cell-inflamed, and intermediate groups. Associations between the T cell-inflamed and non-T cell-inflamed group, MYCN amplification, and survival were analyzed by Cox proportional hazards models. Additional survival analysis was conducted after integrating neoantigen load predicted from somatic mutations. Pathways activated in non-T cell-inflamed relative to T cell-inflamed tumors were analyzed using causal network analysis.

Results

Patients with T cell-inflamed high-risk tumors showed improved overall survival compared with those with non-T cell-inflamed tumors (p<0.05), independent of MYCN amplification status, in both TARGET and GMKF cohorts. Higher neoantigen load was also associated with better event-free and overall survival (p<0.005) and was independent of the T cell-inflamed signature. Activation of MYCN, ASCL1, SOX11, and KMT2A transcriptional programs was inversely correlated with the T cell-inflamed signature in both cohorts.

Conclusions

Our results indicate that tumors from children with high-risk neuroblastoma harboring a strong T cell-inflamed signature have a more favorable clinical outcome, and neoantigen load is a prognosis predictor, independent of T cell inflammation. Strategies to target SOX11 and other signaling pathways associated with non-T cell-inflamed tumors should be pursued as potential immune-potentiating interventions.
Innovative therapeutic strategy for B-cell malignancies that combines obinutuzumab and cytokine-induced killer cells
Authors: Dalla Pietà Anna , Cappuzzello Elisa , Palmerini Pierangela , Ventura Annavera , Visentin Andrea , Astori Giuseppe , Chieregato Katia , Mozzo Valentina , Perbellini Omar , Tisi Maria Chiara , Trentin Livio , Visco Carlo , Ruggeri Marco , Sommaggio Roberta , Rosato Antonio
Published: July 2021

Background

Patients affected by aggressive B-cell malignancies who are resistant to primary or salvage chemoimmunotherapy have an extremely poor prognosis and limited therapeutic options. Promising therapeutic success has been achieved with the infusion of CD19 chimeric antigen receptor-T cells, but several limits still restrain the administration to a limited proportion of patients. This unmet clinical need might be fulfilled by an adoptive immunotherapy approach that combines cytokine-induced killer (CIK) cells and monoclonal antibodies (mAb) to the CD20 antigen. Indeed, CIK cells are an effector population endowed with antitumor activity, which can be further improved and antigen-specifically redirected by clinical-grade mAb triggering antibody-dependent cell-mediated cytotoxicity.

Methods

CIK cells were generated from peripheral blood of patients affected by different B-cell malignancies using a blinatumomab-based cell culture protocol. Effector cells were combined with the anti-CD20 mAb obinutuzumab and their therapeutic activity was assessed both in vitro and in vivo.

Results

CIK cells were successfully expanded in clinically relevant numbers, starting from small volumes of peripheral blood with extremely low CD3+ counts and high tumor burden. This relied on the addition of blinatumumab in culture, which leads to the simultaneous expansion of effector cells and the complete elimination of the neoplastic component. Moreover, CIK cells were highly cytotoxic in vitro against both B-cell tumor cell lines and autologous neoplastic targets, and had a significant therapeutic efficacy against a B-cell malignancy patient-derived xenograft on in vivo transfer.

Conclusions

The combination of an easily expandable CIK cell effector population with a mAb already in clinical use establishes a tumor antigen-specific redirection strategy that can be rapidly translated into clinical practice, providing an effective therapeutic alternative for B-cell malignancies without any need for genetic modifications. Additionally, the approach can be potentially applied to an extremely vast array of different tumors by simply substituting the targeting mAb.
#3131 Stimulation of the ventrolateral prefrontal cortex speeds up evidence accumulation in conflictual-uncertain environments
Authors: Mandali Alekhya , Guzman Natalie Valle , Voon Valerie
Published: July 2021

Introduction

Evaluation of the available choices, an integral step in decision-making, leads to the selection of the optimal and most rewarding one. This process of choice selection depends on its features such as value and reward-likelihood, which form the basis for constructs such as Conflict- easy or difficult (difference between reward probabilities of the stimuli-pairs) and Uncertainty- low, medium, or high (inverse U-shaped probability-uncertainty function).The ventrolateral prefrontal cortex (vlPFC) has been implicated in various processes ranging from uncertainty processing to washing behaviours in Obsessive-compulsive disorder (OCD). Here, we target the vlPFC using trans-cranial stimulation, to modulate decision-making behaviours in the context of conflict and uncertainty.

Methods

Using a single-blinded design, we tested 60 healthy controls (30 per group) randomly allocated to either active (continuous theta burst protocol c-TBS) or sham group. The c-TBS protocol used the standard three-pulse burst design repeated every 200ms, with a total of 600 pulses delivered at stimulation intensity set at 80% of the participants Active Motor Threshold. The sham stimulation was delivered with the coil positioned at a 90 angle to the target. Post-stimulation (active or sham), the participants completed 134 trials of the sequential learning paradigm, which consisted of 2 stages. We focused on the second stage of the task, specifically on Conflict and Uncertainty which were used as model dependents of a hierarchical drift-diffusion model(HDDM) to extract the parameters (a- amount of evidence accumulated before making a decision) and the drift rates (v- information processing speed).

Results

Using the choice and reaction time information as inputs to the HDDM model, we extracted the threshold and drift rates for all conflict and uncertainty conditions. A Bayesian repeated-measures ANOVA on threshold showed a very strong evidence for the main effect of conflict-uncertainty condition (BF10 = 5.2 x 1010) and stimulation by condition interaction (BF10 = 6.4 x 103) but no main effect of stimulation (BF10 = 0.46). A Bayesian Independent samples t-test showed strong evidence (BF10 = 77.54) for stimulation to speed up the decision-making process, by decreasing the amount of evidence accumulated (threshold)whilst selecting a choice in a difficult uncertain scenario.

Conclusions

By applying an inhibitory based stimulation protocol tovlPFC, we show a modulation in behaviour specific to context, where the choices are similar in value but their reward likelihood being uncertain. This finding has key implications to the design of novel interventions for OCD.
#3105 How does self-report of mood symptoms compare with observer assessments after acquired brain injury
Authors: Paramlall M , Bakar I , Kandasamy R , Gadhvi A , Holloway C , Harding S , Tyagi H
Published: July 2021

Objectives

Post acquired brain injury (ABI) depression has been implicated in different patient outcomes such as prospective cognition, cognitive impairment, rehabilitation outcome, and quality of life. However, there have been no studies identified in the literature, investigating post ABI insight into depression across varied cognitive abilities. Here we looked at ABI patient insight into their depression across a range of cognitive abilities and compared this to an observed or an objective measure of depression.

Methods

A retrospective cohort of 24 individuals with ABI (depressed and non-depressed) seen in a neuropsychiatry outpatient clinic between 2019 and 2020 completed a Patient Health Questionnaire-9 (PHQ-9), self-reported depression scale and had a Neuropsychiatry Inventory Questionnaire(NPI-Q), an observer assessment with a depression domain. The patients also underwent a formal cognitive examination using the Montreal Cognitive Assessment (MoCA).

Results

Non-depressed ABI and depressed ABI individuals with a wide range of cognitive abilities demonstrated good insight into their depression when matched to the observer rating. Chi-Square Test showed little variation between the PHQ-9 and NPI-Q Depression data sets; Wilcoxon Signed Ranks Test: Z Test -4.08, p<0.001, Effect Size 0.87 and Spearman’s rho showed positive correlation between the two data sets (Correlation Coefficient 0.527, P<0.008). Therefore, there was a statistically significant agreement between the subjective measure (PHQ-9) and the observed (objective) measure NPIQD and that there was a positive correlation between the two measurement scales for patients with ABI regardless of cognition (as measured by MoCAz score; range -6 to 2.21, mean: -1.17)

Conclusions

These findings indicate (1) self-reported measures of depression in ABI are consistent with observed (objective measures) thus can be used to assess depression in this cohort and (2) ABI patients with a wide range of cognitive abilities would appear to have good insight into their depression.
A note on boundary conditions in Euclidean gravity
Authors: Witten Edward
Published: July 2021

We review what is known about boundary conditions in General Relativity on a spacetime of Euclidean signature. The obvious Dirichlet boundary condition, in which one specifies the boundary geometry, is actually not elliptic and in general does not lead to a well-defined perturbation theory. It is better-behaved if the extrinsic curvature of the boundary is suitably constrained, for instance if it is positive- or negative-definite. A different boundary condition, in which one specifies the conformal geometry of the boundary and the trace of the extrinsic curvature, is elliptic and always leads formally to a satisfactory perturbation theory. These facts might have interesting implications for semiclassical approaches to quantum gravity. April, 2018
SOFC-Supported Hybrid PSOGSA-Optimized Dynamic Voltage Restorer for Power Quality Enhancement
Authors: Sathish Babu P. , Sundarabalan C. K. , Balasundar C.
Published: July 2021

A novel optimal method of a Dynamic Voltage Restorer (DVR) supported by solid oxide fuel cell (SOFC) and its simplified topological structure are proposed. DVR is a power-electronic converter-based device, and the objective of the DVR control system is to minimize supply voltage variations at the load terminals. This is attained by generating a compensating voltage at the series injection transformer. Conventional controllers are mathematical model-based; also, the particular system varies widely, and nonlinear factors make the PI controller tuning more challenging to some extent. As a result, an intelligent PI optimization control method is essential. This paper proposes Hybrid PSOGSA to search for optimal values of two PI control parameters for the [Formula: see text]–[Formula: see text]-axis components by considering a novel bi-objective function. The performance of the test system is analyzed for five test scenarios using the proposed PI controller with SPSO-optimized and Ziegler–Nichols tuning methods. DVR system provides an excellent control performance in the transient and steady states for compensating the sensitive load voltages with almost zero steady-state errors. Simulation results show that the proposed approach can provide improved performance than PSO-optimized and classical PI controllers for the power quality indices measured.
RESEARCH ON TRIBOLOGICAL BEHAVIOR OF Cr3C2-25NiCr-COATED BRAKE DISC
Authors: KILIÇ HALİL , MISIRLI CENK
Published: July 2021

This research presents the results of a comparative study to determine the friction and wear behavior of the high-velocity oxygen fuel (HVOF)-sprayed Cr3C2-25NiCr-coated brake disc. The friction and wear behavior of Cr3C2-25NiCr-coated brake disc (CD) and the sliding against the commercial brake pad were examined on a laboratory-scale disc-pad dynamometer and the findings were compared with those of reference brake disc (UCD). The coating was deposited by means of the HVOF process on a grey cast iron (GCI) substrate. Braking tests were performed according to the SAE-J2430 test standard. The as-sprayed coating was characterized for their microstructure and phase constitution by SEM/EDS and XRD. The results reveal that the coefficient of friction (COF) of CD and UCD varies between 0.42–0.57 and 0.44–0.62, respectively. The Cr3C2-25NiCr-coated brake disc was found to have exhibited a comparable COF and lower wear loss to the reference brake disc. The addition of a ceramic phase to the brake disc coating played an important role in reducing the COF to an acceptable range and improving the sliding wear resistance of the brake pair.
Joint global fluctuations of complex Wigner and deterministic matrices
Authors: Male Camile , Mingo James A. , Péché Sandrine , Speicher Roland
Published: July 2021

We characterize the limiting fluctuations of traces of several independent Wigner matrices and deterministic matrices under mild conditions. A CLT holds but in general the families are not asymptotically free of second-order and the limiting covariance depends the limiting [Formula: see text]-distribution of the deterministic matrices and their transposes and Hadamard products.
Moderate deviations for linear eigenvalue statistics of β-ensembles
Authors: Gao Fuqing , Mu Jianyong
Published: July 2021

We establish a moderate deviation principle for linear eigenvalue statistics of [Formula: see text]-ensembles in the one-cut regime with a real-analytic potential. The main ingredient is to obtain uniform estimates for the correlators of a family of perturbations of [Formula: see text]-ensembles using the loop equations.
The Efficient Mining of Skyline Patterns from a Volunteer Computing Network
Authors: Wu Jimmy Ming-Tai , Teng Qian , Srivastava Gautam , Pirouz Matin , Lin Jerry Chun-Wei
Published: July 2021

In the ever-growing world, the concepts of High-utility Itemset Mining (HUIM) as well as Frequent Itemset Mining (FIM) are fundamental works in knowledge discovery. Several algorithms have been designed successfully. However, these algorithms only used one factor to estimate an itemset. In the past, skyline pattern mining by considering both aspects of frequency and utility has been extensively discussed. In most cases, however, people tend to focus on purchase quantities of itemsets rather than frequencies. In this article, we propose a new knowledge called skyline quantity-utility pattern (SQUP) to provide better estimations in the decision-making process by considering quantity and utility together. Two algorithms, respectively, called SQU-Miner and SKYQUP are presented to efficiently mine the set of SQUPs. Moreover, the usage of volunteer computing is proposed to show the potential in real supermarket applications. Two new efficient utility-max structures are also mentioned for the reduction of the candidate itemsets, respectively, utilized in SQU-Miner and SKYQUP. These two new utility-max structures are used to store the upper-bound of utility for itemsets under the quantity constraint instead of frequency constraint, and the second proposed utility-max structure moreover applies a recursive updated process to further obtain strict upper-bound of utility. Our in-depth experimental results prove that SKYQUP has stronger performance when a comparison is made to SQU-Miner in terms of memory usage, runtime, and the number of candidates.
Design of Self-sustainable Wireless Sensor Networks with Energy Harvesting and Wireless Charging
Authors: Zhou Pengzhan , Wang Cong , Yang Yuanyuan
Published: July 2021

Energy provisioning plays a key role in the sustainable operations of Wireless Sensor Networks (WSNs). Recent efforts deploy multi-source energy harvesting sensors to utilize ambient energy. Meanwhile, wireless charging is a reliable energy source not affected by spatial-temporal ambient dynamics. This article integrates multiple energy provisioning strategies and adaptive adjustment to accomplish self-sustainability under complex weather conditions. We design and optimize a three-tier framework with the first two tiers focusing on the planning problems of sensors with various types and distributed energy storage powered by environmental energy. Then we schedule the Mobile Chargers (MC) between different charging activities and propose an efficient, 4-factor approximation algorithm. Finally, we adaptively adjust the algorithms to capture real-time energy profiles and jointly optimize those correlated modules. Our extensive simulations demonstrate significant improvement of network lifetime (

), increase of harvested energy (15%), reduction of network cost (30%), and the charging capability of MC by 100%.
Are these Artworks Similar? Analysing Visitors’ Judgements on Aesthetic Perception with a Digital Game
Authors: Sprugnoli Rachele , Guerini Marco , Moretti Giovanni , Tonelli Sara
Published: July 2021

Digital games have been used in the context of a cultural experience for several reasons, from learning to socialising and having fun. As a positive side effect, using digital games in a GLAM environment contributes to increasing the visitors’ engagement and making the collections more popular. Along this line, we present in this article an online game for museum environments that serves two goals: asking users to engage with the artworks in a collection in a playful environment, and collecting their feedback on artwork similarity, which may be used by curators to rethink the organisation of digital exhibitions and in general to better understand how visitors perceive artworks. The game is called
PAGANS
(
Playful Art: a GAme oN Similarity
), and is designed to collect similarity judgements about artworks. The software was implemented following some principles of gamification in order to quickly leverage similarity information in the cultural heritage domain while increasing user engagement and fun. The game, involving pairs of players, was used during two large public events to collect different data about the players’ behaviour and to investigate how these dimensions correlate with aesthetic perception. A thorough statistical analysis shows that age and (self-declared) gender correlates with the time and the number of moves needed to complete a session. These dimensions also link to the relevance of colour and shape in judging similarity. These findings suggest that, although artwork similarity is very subjective and may vary based on a person’s background, some trends can be identified when considering the subjects’ gender and age. This could have some practical implications; for example, it could be used to support art curators in creating digital exhibitions by grouping artworks in novel, user-centred ways.
The information retrieval anthology 2021
Authors: Potthast Martin , Stein Benno , Hagen Matthias
Published: July 2021

The Information Retrieval Anthology, IR Anthology for short, is an endeavor to create a comprehensive collection of metadata and full texts of IR-related publications. We report on its first release, the use cases it can serve, as well as the challenges lying ahead to develop it towards a resource that serves the IR community for years to come. The IR Anthology's metadata browser and full text search engine are available at IR.webis.de.
Toward a fairer information retrieval system
Authors: Gao Ruoyuan
Published: July 2021

With the increasing popularity and social influence of information retrieval (IR) systems, various studies have raised concerns on the presence of bias in IR and the social responsibilities of IR systems. Techniques for addressing these issues can be classified into
pre-processing
,
in-processing
and
post-processing.
Pre-processing reduces bias in the data that is fed into machine learning models. In-processing encodes fairness constraints as a part of the objective function or learning process. Post-processing operates as a top layer over the trained model to reduce the presentation bias exposed to users. This dissertation explored ways to bring the pre-processing and post-processing approaches, together with the fairness-aware evaluation metrics, into a unified framework as an attempt to break the vicious cycle of bias and improve fairness in IR.

We first investigated the existing bias presented in search engine results. Specifically, we focused on the top-k fairness ranking in terms of statistical parity fairness and disparate impact fairness definitions. With Google search and a general purposed text cluster as a lens, we explored several topical diversity fairness ranking strategies to understand the relationship between relevance and fairness in search results. Our experimental results showed that different fairness ranking strategies resulted in distinct utility scores and performed differently with distinct datasets. Second, to further investigate the relationship of data and fairness algorithms, we developed a statistical framework that was able to facilitate various analysis and decision making. Our framework could effectively and efficiently estimate the domain of data and solution space. We derived theoretical expressions to identify the fairness and relevance bounds for data of different distributions, and applied them to both synthetic datasets and real world datasets. We presented a series of use cases to demonstrate how our framework was applied to associate data and provide insights to fairness optimization problems. Third, we proposed an evaluation metric FAIR for the ranking results that encoded fairness, diversity, novelty and relevance. This metric offered a new perspective of evaluating fairness-aware ranking results. Based on this metric, we developed an effective ranking algorithm that jointly optimized for fairness and utility. Our experiments showed that our new metric was able to highlight results that achieved good user utility and fair information exposure at the same time. We showed how FAIR metric related to existing metrics through correlation analysis and case studies, and demonstrated the effectiveness of our FAIR-based algorithm.
Exploring strategies to prevent harm from web search
Authors: Zimmerman Steven
Published: July 2021

Web search, the process of seeking and finding information online, is an ubiquitous activity engrained in the lives of many individuals and much of broader society. This activity, which has brought many benefits to individuals and society, has also opened the door to many harms, such as echo chambers, loss of privacy and exposure to misinformation. Members of the information retrieval (IR) community now recognize the dangers of the search technologies commonplace in our daily lives. The upshot of this recognition are growing efforts to address these dangers by the IR community. These efforts focus heavily on system oriented solutions, but give limited focus on behavioural and cognitive biases and behaviours of the search and even less attention to interventions designed to address these biases and behaviours. As such, a theoretical framework is proposed, with behavioural and cognitive strategies as a core component of interactive Web search environments designed to minimize harm.

Using the framework as the foundation, this thesis presents a number of offline and online studies to evaluate
nudging
, a popular intervention strategy rooted in the field of behavioural economics, and
boosting
, a successful intervention strategy from the cognitive sciences, as strategies to reduce risk of harm in Web search. The key takeaway from these studies being that both
boosting
and
nudging
should be considered as viable approaches for harm prevention in Web search environments, in addition to pure system and algorithmic solutions. Additional contributions of this thesis include methods of study design for the comparison of multiple paradigms that promote improved decision making, along with a set of evaluation metrics to measure the success of the IR system and user performance as they relate to the harms being prevented. Future research is needed to confirm the effectiveness of these strategies for other types of harms.
Neural methods for effective, efficient, and exposure-aware information retrieval
Authors: Mitra Bhaskar
Published: July 2021

Neural networks with deep architectures have demonstrated significant performance improvements in computer vision, speech recognition, and natural language processing. The challenges in information retrieval (IR), however, are different from these other application areas. A common form of IR involves ranking of documents---or short passages---in response to keyword-based queries.
Effective
IR systems must deal with query-document vocabulary mismatch problem, by modeling relationships between different query and document terms and how they indicate relevance. Models should also consider lexical matches when the query contains rare terms---such as a person's name or a product model number---not seen during training, and to avoid retrieving semantically related but irrelevant results. In many real-life IR tasks, the retrieval involves extremely large collections---such as the document index of a commercial Web search engine---containing billions of documents.
Efficient
IR methods should take advantage of specialized IR data structures, such as inverted index, to efficiently retrieve from large collections. Given an information need, the IR system also mediates how much exposure an information artifact receives by deciding whether it should be displayed, and where it should be positioned, among other results.
Exposure-aware
IR systems may optimize for additional objectives, besides relevance, such as parity of exposure for retrieved items and content publishers.

In this thesis, we present novel neural architectures and methods motivated by the specific needs and challenges of IR tasks. We ground our contributions with a detailed survey of the growing body of neural IR literature [Mitra and Craswell, 2018]. Our key contribution towards improving the
effectiveness
of deep ranking models is developing the Duet principle [Mitra et al., 2017] which emphasizes the importance of incorporating evidence based on both patterns of exact term matches and similarities between learned latent representations of query and document. To
efficiently
retrieve from large collections, we develop a framework to incorporate query term independence [Mitra et al., 2019] into any arbitrary deep model that enables large-scale precomputation and the use of inverted index for fast retrieval. In the context of stochastic ranking, we further develop optimization strategies for exposure-based objectives [Diaz et al., 2020]. Finally, this dissertation also summarizes our contributions towards benchmarking neural IR models in the presence of large training datasets [Craswell et al., 2019] and explores the application of neural methods to other IR tasks, such as query auto-completion.
Economies with complex property rights
Authors: Balbuzanov Ivan , Kotowski Maciej H.
Published: July 2021

We discuss the exclusion core, a solution concept for object-allocation and object-exchange problems. The exclusion core is based on the right of exclusion and is especially useful for the analysis of economies with complicated property arrangements, such as those with shared ownership. The exclusion core coincides with the (strong) core in classic settings, and is closely related to the celebrated Top Trading Cycles algorithm.
Study of the Failure Mode of a Jointed Rock Mass due to a Stress Wave
Authors: Qian Xi Kun , Li Cong Cong
Published: July 2021

The mechanical response and failure process of a jointed rock mass subjected to dynamic loading is very important for the safety and stability of rock engineering projects. In this study, we use RFPA2D‐Dynamic, a rock dynamic failure process analysis platform, to establish a two‐dimensional impact model of a jointed rock mass to analyze the mechanism of crack propagation in a jointed rock mass with preexisting cracks under dynamic loading. We discuss the influence of the stress wavelength and precrack inclination on the dynamic failure process and mode of the rock mass and compare this failure process with the failure model under static loading. The results show that the dynamic failure process and crack initiation type of a jointed rock mass are closely related to the stress wavelength. For a given peak, as the stress wavelength increases, the failure mode changes from local cracking that occurs above the precracks to a global instability caused by wing cracks. Meanwhile, as the wavelength increases, the shear cracks and mixed tensile‐shear cracks generated at the two ends of the precracks are replaced by tensile cracks. The precrack inclination on a jointed rock mass mainly affects the strength of the jointed rock mass and the final failure mode. Specifically, when the joint inclination is small, the rock mass is severely damaged in the region above the precracks because the stress wave forms a region of cracks with a concentrated distribution. As the joint inclination increases, the damaged region becomes larger while the rock mass is less prone to failure; the strength of the rock mass gradually increases, and the wing cracks produced at the two ends of precracks propagate toward the upper and lower ends of the rock mass. However, when the stress wavelength is small, the precracks of different inclinations form cracks in the region above the precracks with a length similar to the precracks. For this condition, the propagation of the cracks is mainly controlled by the stress wavelength, while the influence of the inclination of the precracks is not significant. There is a significant difference between the failure modes of a rock specimen under dynamic loading or static loading because the stress wave produces a reflected tension wave in the direction parallel to the wave attack of the joint plane, which leads to spalling, while the wing cracks are more likely to occur under static loading.
A Pilot Study of Detecting Individual Sleep Apnea Events Using Noncontact Radar Technology, Pulse Oximetry, and Machine Learning
Authors: Toften Ståle , Kjellstadli Jonas T. , Tyvold Stig S. , Moxness Mads H. S.
Published: July 2021

The gold standard for assessing sleep apnea, polysomnography, is resource intensive and inconvenient. Thus, several simpler alternatives have been proposed. However, validations of these alternatives have focused primarily on estimating the apnea‐hypopnea index (apnea events per hour of sleep), which means information, clearly important from a physiological point of view such as apnea type, apnea duration, and temporal distribution of events, is lost. The purpose of the present study was to investigate if this information could also be provided with the combination of radar technology and pulse oximetry by classifying sleep apnea events on a second‐by‐second basis. Fourteen patients referred to home sleep apnea testing by their medical doctor were enrolled in the study (6 controls and 8 patients with sleep apnea; 4 mild, 2 moderate, and 2 severe) and monitored by Somnofy (radar‐based sleep monitor) in parallel with respiratory polygraphy. A neural network was trained on data from Somnofy and pulse oximetry against the polygraphy scorings using leave‐one‐subject‐out cross‐validation. Cohen’s kappa for second‐by‐second classifications of no event/event was 0.81, or almost perfect agreement. For classifying no event/hypopnea/apnea and no event/hypopnea/obstructive apnea/central apnea/mixed apnea, Cohen’s kappa was 0.43 (moderate agreement) and 0.36 (fair agreement), respectively. The Bland‐Altman 95% limits of agreement for the respiratory event index (apnea events per hour of recording) were ‐8.25 and 7.47, and all participants were correctly classified in terms of sleep apnea severity. Furthermore, the results showed that the combination of radar and pulse oximetry could be more accurate than the two technologies separately. Overall, the results indicate that radar technology and pulse oximetry could reliably provide information on a second‐by‐second basis for no event/event which could be valuable for management of sleep apnea. To be clinically useful, a larger study is necessary to validate the algorithm on a general population.
Distal Patellar Tendon Avulsion Associated with an ACL Tear in a Teenager: A Case Report and Review of the Literature
Authors: Steiger Christina , Coulin Benoit , Vendeuvre Tanguy , Tabard-Fougere Anne , De Marco Giacomo , Habre Céline , Dayer Romain , Ceroni Dimitri
Published: July 2021

Distal patellar tendon avulsions are rare injuries in healthy individuals, and to date, no case affecting skeletally mature teenagers and adolescents has been reported. In the majority of cases, distal patellar tendon avulsions are associated with severe intra-articular knee lesions, signifying a high-energy trauma. We present the case of a 15.5-year-old female who was admitted to the emergency department after a knee injury. The mechanism of injury was a combination of landing after a jump off a scooter and sudden deceleration with a fixed foot. Lateral radiographs revealed a distal patellar tendon avulsion. An MRI was conducted to accurately diagnose concomitant lesions. The MRI revealed a complete tear of the ACL, and associated bone bruises on the lateral femoral condyle, and also on the posterolateral tibial plateau. A knee joint exam under general anesthesia demonstrated good stability during valgus stress testing and only a grade 1 positive Lachman test. Therefore, we decided to only reconstruct the extensor mechanism and to abstain from a primary ACL reconstruction. The presented case and review of the literature demonstrate the clinical relevance of this atypical lesion. In fact, a distal patellar tendon avulsion after physeal fusion of the proximal tibia should raise a strong suspicion of severe associated intra-articular knee lesions and requires prompt MRI investigation. However, controversy still exists regarding the management of these injuries, in particular concerning the question of whether to address both injuries in a single stage or in 2 stages.
Denoising Speech Based on Deep Learning and Wavelet Decomposition
Authors: Wang Li , Zheng Weiguang , Ma Xiaojun , Lin Shiming
Published: July 2021

The work proposed a denoising speech method using deep learning. The predictor and target network signals were the amplitude spectra of the wavelet-decomposition vectors of the noisy audio signal and clean audio signal, respectively. The output of the network was the amplitude spectrum of the denoised signal. Besides, the regression network used the input of the predictor to minimize the mean square error between its output and input targets. The denoised wavelet-decomposition vector was transformed back to the time domain by the output amplitude spectrum and the phase of the wavelet-decomposition vector. Then, the denoised speech was obtained by the inverse wavelet transform. This method overcame the problem that the frequency and time resolution of the short-time Fourier transform could not be adjusted. The noise reduction effect in each frequency band was improved due to the gradual reduction of the noise energy in the wavelet-decomposition process. The experimental results showed that the method has a good denoising effect in the whole frequency band.
A Study on the Relationship between Public Derivative Big Data and Industrial Policymaking: Taking Bike Sharing as an Example
Authors: Song Huilin
Published: July 2021

Smart government is an important part of the smart world. The use of big data analysis technology can effectively improve the government’s ability of fine management. Taking China’s bike-sharing industry as the research object, we study the relationship between public-derived big data and industrial policy. First, a feature-enhanced short text clustering method is proposed to perform topic clustering on publicly derived big data. Second, keyword extraction based on word frequency is used to quantify the text of industrial policy. Finally, time is taken as the main line to analyze the co-occurrence of clustering topics and keywords. The results show that (1) the feature enhancement method we proposed can effectively improve the clustering effect. (2) There is a great correlation between the industrial policy and the information mined by Weibo, but there is an obvious lag. Rational use of public-derived big data will effectively help the industrial policy to be released in a better and faster way.
A Clustering Application Scenario Based on an Improved Self-Organizing Feature Mapping Network System
Authors: Cao Qian
Published: July 2021

Categorizing national football teams by level is challenging because there is no standard of reference. Therefore, the self-organizing feature mapping network is used to solve this problem. In this paper, appropriate sample data were collected and an appropriate self-organizing feature mapping network model was built. After training, we obtained the classification results of 4 grades of 16 major Asian football national teams. As for the classification results, it is different to normalize the input data and not to normalize the input data. The classification results accord with our subjective cognition, which indicates the rationality of self-organizing feature mapping network in solving the classification problem of national football teams. In addition, the paper makes a detailed analysis of the classification results of the Chinese team and compares the gap between the Chinese team and the top Asian teams. It also analyses the impact of the normalization of input data on the classification results, taking Saudi Arabia as an example.
Computer-Based Tutorial to Enhance the Informed Consent Process for Cataract Surgery in Serbian- or Turkish-Speaking Patients
Authors: Ruiss Manuel , Findl Oliver , Prinz Ana , Kahraman Guenal , Barisic Sava , Muftuoglu Orkun , Hirnschall Nino
Published: July 2021

Introduction: This study analyses if a translated version of the CatInfo tool increases the knowledge of Serbian- and Turkish-speaking patients about cataract surgery. Methods: In total, 61 cataract patients, literate in Serbian or Turkish, were randomly allocated into two groups. Via an interactive computer-based tool (“CatInfo”), patients either saw a detailed audio-visual presentation about cataract surgery (study group) or a “placebo” video (control group). Afterwards, all participants had a face-to-face discussion with an ophthalmologist. Immediately after the interview and on the day of surgery, all patients had to fill out a questionnaire including knowledge and demographic questions. Patients in the study group were further asked about their satisfaction with the CatInfo tool and the usefulness of such a device before other interventions. Results: Patients in the study group answered significantly more questions correctly compared to the control group, and this information gain remained stable over a 1-week period. There was a significant low negative correlation between educational level and the test results, whereas age and computer habits of the participants did not have an influence on correct answers. Satisfaction with the CatInfo tool was high in the Serbian and the Turkish group (96% and 84%, respectively), and 92% of Serbian patients as well as 62% of the Turkish patients rated that they could imagine to use such a device before any other surgery. Discussion/Conclusion: The translated version of the CatInfo tool improved patients’ knowledge, and this information gain remained stable until the day of the surgery.
Reduced Achilles Tendon Stiffness Disrupts Calf Muscle Neuromechanics in Elderly Gait
Authors: Krupenevich Rebecca L. , Beck Owen N. , Sawicki Gregory S. , Franz Jason R.
Published: July 2021

Older adults walk slower and with a higher metabolic energy expenditure than younger adults. In this review, we explore the hypothesis that age-related declines in Achilles tendon stiffness increase the metabolic cost of walking due to less economical calf muscle contractions and increased proximal joint work. This viewpoint may motivate interventions to restore ankle muscle-tendon stiffness, improve walking mechanics, and reduce metabolic cost in older adults.