Miracle-dz/UniFAR-FTUs huggingface dataset:
Detecting the large entries of a sparse covariance matrix in sub-quadratic time

The covariance matrix of a $p$-dimensional random variable is a fundamental quantity in data analysis. Given $n$ i.i. d. observations, it is typically estimated by the sample covariance matrix, at a computational cost of $O(np^{2})$ operations. When $n,p$ are large, this computation may be prohibitively slow. Moreover, in several contemporary applications, the population matrix is approximately sparse, and only its few large entries are of interest. This raises the following question, at the focus of our work: Assuming approximate sparsity of the covariance matrix, can its large entries be detected much faster, say in sub-quadratic time, without explicitly computing all its $p^{2}$ entries? In this paper, we present and theoretically analyze two randomized algorithms that detect the large entries of an approximately sparse sample covariance matrix using only $O(np\text{ poly log } p)$ operations. Furthermore, assuming sparsity of the population matrix, we derive sufficient conditions on the underlying random variable and on the number of samples $n$, for the sample covariance matrix to satisfy our approximate sparsity requirements. Finally, we illustrate the performance of our algorithms via several simulations.
The hydrodynamical response of a tilted circumbinary disc: linear theory and non-linear numerical simulations

In this paper we present an analytical and numerical study of the response of a circumbinary disc subject to the tidal-forcing of a binary with a fixed circular orbit. We consider fluid discs with a range of thicknesses and binaries with a range of mass ratios, orbital separations and inclination angles. Our numerical simulations are implemented using a SPH code. For our unperturbed disc models, we write a scaling relation for the shear viscosity and deduce that the disc thickness cannot be varied without affecting the viscosity in these kinds of SPH disc models. It is found that maintainance of an inner cavity owing to the tidal truncation of the disc is effective for non-zero orbital inclinations. Also we show that our model discs may precess approximately like rigid bodies, provided that the disc is able to communicate on a length scale comparable to the inner boundary radius by either sonic or viscous effects, in a sufficiently small fraction of the local precession period. Furthermore, the disc precession period may tend to infinity if the disc outer edge is allowed to become arbitrarily large, the disc suffering only a modest quasi-steady warp near the inner boundary. When the disc response is linear, or weakly non-linear, the precession periods and the forms of warping that we measure yield reasonable quantitative agreement with the analytical expressions that we derive from a linear response calculation. For a stronger disc response the results can agree poorly with our linear analysis, although some qualitative features of the response remain intact. We show that the response of a disc of non-interacting particles is qualitatively different from this. The work presented in this paper is of relevance to a number of astrophysical phenomena of current interest in star and planet formation.
DVFS performance prediction for managed multithreaded applications

Making modern computer systems energy-efficient is of paramount importance. Dynamic Voltage and Frequency Scaling (DVFS) is widely used to manage the energy and power consumption in modern processors; however, for DVFS to be effective, we need the ability to accurately predict the performance impact of scaling a processor's voltage and frequency. No accurate performance predictors exist for multithreaded applications, let alone managed language applications. In this work, we propose DEP+BURST, a new performance predictor for managed multithreaded applications that takes into account synchronization, inter-thread dependencies, and store bursts, which frequently occur in managed language workloads. Our predictor lowers the performance estimation error from 27% for a state-of-the-art predictor to 6% on average, for a set of multithreaded Java applications when the frequency is scaled from 1 to 4 GHz. We also novelly propose an energy management framework that uses DEP+BURST to save energy while meeting performance goals within a user-specified bound. Our proposed energy manager delivers average energy savings of 13% and 19% for a user-specified slowdown of 5% and 10% for memory-intensive Java benchmarks. Accurate performance predictors are key to achieving high performance while keeping energy consumption low for managed language applications using DVFS.
Diagnosis and management of Castleman disease.

BACKGROUND Castleman disease is an uncommon lymphoproliferative disorder characterized as either unicentric or multicentric. Unicentric Castleman disease (UCD) is localized and carries an excellent prognosis, whereas multicentric Castleman disease (MCD) is a systemic disease occurring most commonly in the setting of HIV infection and is associated with human herpesvirus 8. MCD has been associated with considerable morbidity and mortality, and the therapeutic landscape for its management continues to evolve. METHODS The available medical literature on UCD and MCD was reviewed. The clinical presentation and pathological diagnosis of Castleman disease was reviewed, along with associated disorders such as certain malignancies and autoimmune complications. RESULTS Surgical resection remains the standard therapy for UCD, while systemic therapies are required for the management of MCD. Rituximab monotherapy is the mainstay of therapy; however, novel therapies targeting interleukin 6 may represent a treatment option in the near future. Antiviral strategies as well as single-agent and combination chemotherapy with glucocorticoids are established systemic therapies. The management of Castleman disease also requires careful attention to potential concomitant infections, malignancies, and associated syndromes. CONCLUSIONS UCD and MCD constitute uncommon but well-defined clinicopathologic entities. Although UCD is typically well controlled with local therapy, MCD continues to pose formidable challenges in management. We address historical chemotherapy-based approaches to this disease as well as recently developed targeted therapies, including rituximab and siltuximab, that have improved the outcome for newly diagnosed patients. Ongoing research into the management of MCD is needed.
The Information Politics of Journalism in a Post-Truth Age

In the so-called post-truth age, criticism challenging the representational accuracy and political orientation of journalists has become an indelible part of the realm of political contestation. Although “post-truth” is riddled with conceptual shortcomings, its usage to describe the contemporary epistemic moment directs attention to the underlying issues it encompasses. This is particularly the case for journalism in the United States where antagonism toward journalists has already been a regular feature of political discourse, and has been magnified through the rhetoric of Donald Trump. Journalists face increasing challenges in their attempt to occupy the symbolic communicative center of democratic society while remaining outside of governing power. Contemporary information politics are marked by a power struggle among competing groups to not merely contest claims within journalistic content but to contest the journalists making the claims. Given this context, this article argues that the epistemic context of contemporary journalism demands that journalists do more to develop arguments legitimating their claims to render valid judgments. This metacommunication includes a more vigorous and public articulation of the social value journalists offer, a self-critical stance through which they can address their weaknesses and limitations, and a defense against self-interested criticism directed at them by political actors.
From the cradle to the grave: age differences in attachment from early adulthood to old age.

OBJECTIVE Although attachment dynamics are thought to be important across the life span, relatively few studies have examined attachment processes beyond young adulthood. Extant research on age differences in attachment orientation has yielded conflicting results and interpretations. The purpose of this study was to provide a more complete picture of age-related differences in attachment anxiety and avoidance. METHOD We examined attachment anxiety and avoidance in 86,555 Internet respondents (71.8% female) ranging in age from 18 to 70. RESULTS We found that attachment anxiety was highest among younger adults and lowest among middle-aged and older adults. Attachment avoidance showed less dramatic age differences overall but was highest among middle-aged adults and lowest among younger and older adults. In addition, partnered individuals reported lower levels of attachment anxiety and avoidance compared to single individuals, particularly in younger and older adulthood. Women also reported slightly higher anxiety and avoidance compared to men, especially in young adulthood. CONCLUSIONS Findings are discussed in the context of life span changes in social roles, normative personality development, and emotion regulation throughout adulthood.
A study of inflammatory mediators in the human tympanosclerotic middle ear.

OBJECTIVE To analyze immunocompetent cells as well as 2 factors involved in inflammation and also thought to be involved in bone remodeling-interleukin 6 (IL-6) and inducible nitric oxide synthase in the human middle ear, including the tympanic membrane. DESIGN Biopsy specimens were obtained from the human middle ear and tympanic membrane during surgery. Using an immunohistochemical technique, the expression of macrophages, T cells, B cells, IL-6, and inducible nitric oxide synthase were analyzed. MATERIALS Nine biopsy specimens from tympanic membranes in children having a transtympanic ventilation tube inserted as a treatment for secretory otitis media and 11 biopsy specimens from tympanosclerotic plaques from patients with chronic otitis media and tympanosclerosis. RESULTS More positively stained specimens showing macrophages, B cells, and IL-6 were seen in the biopsy specimens from children with secretory otitis media compared with the biopsy specimens from patients with chronic otitis media and tympanosclerosis. The biopsy specimens from patients with chronic otitis media and tympanosclerosis more often showed positive stainings for inducible nitric oxide synthase than the biopsy specimens from children with secretory otitis media. The presence of IL-6 and inducible nitric oxide synthase was shown by staining to be mostly in the surface cells, while macrophages and B cells were stained deeper in the tissues, in connective tissue, or around sclerotic lesions. CONCLUSIONS The 2 patient groups differed in antigen presentation so that macrophages, B cells, and IL-6 were labeled more frequently in patients with secretory otitis media, that is, an early phase of the disease. Inducible nitric oxide synthase was seen more frequently in the patients with already established tympanosclerosis in a later phase of the disease.
Structural anatomy of pure and hemianopic alexia

Background: The two most common types of acquired reading disorder resulting from damage to the territory of the dominant posterior cerebral artery are hemianopic and pure alexia. Patients with pronounced hemianopic alexia have a right homonymous hemianopia that encroaches into central or parafoveal vision; they read individual words well, but generate inefficient reading saccades when reading along a line of text. Patients with pure alexia also often have a hemianopia but are more disabled, making frequent errors on individual words; they have sustained damage to a brain region that supports efficient word identification. Objective: To investigate the differences in lesion site between hemianopic alexia and pure alexia groups, as rehabilitative techniques differ between the two conditions. Methods: High-resolution magnetic resonance images were obtained from seven patients with hemianopic alexia and from six patients with pure alexia caused by a left occipital stroke. The boundary of each lesion was defined and lesion volumes were then transformed into a standard stereotactic space so that regional comparisons could be made. Results: The two patient groups did not differ in terms of damage to the medial left occipital lobe, but those with pure alexia had additional lateral damage to the posterior fusiform gyrus and adjacent tissue. Conclusions: Clinicians will be able to predict the type of reading disorder patients with left occipital lesions have from simple tests of reading speed and the distribution of damage to the left occipital lobe on brain imaging. This information will aid management decisions, including recommendations for reading rehabilitation.
Multidimensional Characterization and Differentiation of Neurons in the Anteroventral Cochlear Nucleus

Multiple parallel auditory pathways ascend from the cochlear nucleus. It is generally accepted that the origin of these pathways are distinct groups of neurons differing in their anatomical and physiological properties. In extracellular in vivo recordings these neurons are typically classified on the basis of their peri-stimulus time histogram. In the present study we reconsider the question of classification of neurons in the anteroventral cochlear nucleus (AVCN) by taking a wider range of response properties into account. The study aims at a better understanding of the AVCN's functional organization and its significance as the source of different ascending auditory pathways. The analyses were based on 223 neurons recorded in the AVCN of the Mongolian gerbil. The range of analysed parameters encompassed spontaneous activity, frequency coding, sound level coding, as well as temporal coding. In order to categorize the unit sample without any presumptions as to the relevance of certain response parameters, hierarchical cluster analysis and additional principal component analysis were employed which both allow a classification on the basis of a multitude of parameters simultaneously. Even with the presently considered wider range of parameters, high number of neurons and more advanced analytical methods, no clear boundaries emerged which would separate the neurons based on their physiology. At the current resolution of the analysis, we therefore conclude that the AVCN units more likely constitute a multi-dimensional continuum with different physiological characteristics manifested at different poles. However, more complex stimuli could be useful to uncover physiological differences in future studies.
Effect of Dividend Announcement on Shareholders' Value: Evidence from Dhaka Stock Exchange

Academic literature suggests that dividend payments should have no impact on shareholders value in the absence of taxes and market imperfections. Hence, companies should invest excess funds in the positive net present value projects instead of paying out them to the shareholders. Literature also suggests that market valuation of stocks depends on the expected future dividends. If company pays out all of the earnings, funds for future investment will decrease and dividend may not increase in the future. Moreover, when dividend is taxable, paying out more cash would increase the shareholders tax liability. Despite these theoretical arguments for not paying dividends, companies often pay cash dividends to their shareholders possibly to signal information about the future earnings prospects. Our empirical results based on 137 samples of dividend paying companies listed on Dhaka Stock Exchange, showed that investors do not gain value from dividend announcement. Indeed shareholders lost about 20 percent of value over a period of 30 days prior to the dividend announcement through to 30 days after the announcement. The lost value may be partially compensated because of the current dividend yield. Overall, the evidence tends to support the dividend irrelevancy hypothesis. Evidence also indicates that dividend payment does not signal any information to the investors, which needs to be further investigated.
Social anxiety disorder : Functional neuroimaging and social cognitive features

In psychiatric research, nuclear imaging methods are complementary to those of magnetic resonance imaging (MRI). Nuclear methods can be used to study regional neural activity, and offer quantitative means of studying neurochemistry in-vivo. While recent neuroimaging reviews in social anxiety disorder (SAD) have predominantly focused on studies using MRI, the purpose of this paper was to review the contribution of nuclear imaging methods in SAD research to date. We discuss developments in, and future directions of nuclear imaging research in this field.
A Linear Model for Transcription Factor Binding Affinity Prediction in Protein Binding Microarrays

Protein binding microarrays (PBM) are a high throughput technology used to characterize protein-DNA binding. The arrays measure a protein's affinity toward thousands of double-stranded DNA sequences at once, producing a comprehensive binding specificity catalog. We present a linear model for predicting the binding affinity of a protein toward DNA sequences based on PBM data. Our model represents the measured intensity of an individual probe as a sum of the binding affinity contributions of the probe's subsequences. These subsequences characterize a DNA binding motif and can be used to predict the intensity of protein binding against arbitrary DNA sequences. Our method was the best performer in the Dialogue for Reverse Engineering Assessments and Methods 5 (DREAM5) transcription factor/DNA motif recognition challenge. For the DREAM5 bonus challenge, we also developed an approach for the identification of transcription factors based on their PBM binding profiles. Our approach for TF identification achieved the best performance in the bonus challenge.
Learning Chinese Idioms through iPads.

iPads. Students’ short-term and long-term learning was measured; feedback from a questionnaire and artifacts created during the learning process are also reported here. The results show that the textual and visual illustrations of the idioms created by the heritage learners facilitated their learning of the idioms. The results also show that the learners enjoyed this mobile way of learning. This study identified three keys areas that will need to be addressed in the next cycle of action research: learner collaboration, peer learning and assessment, and technological issues.
Parallel algorithms in external memory

External memory (EM) algorithms are designed for computational problems in which the size of the internal memory of the computer is only a small fraction of the problem size. The Parallel Disk Model (PDM) of Vitter and Shriver is widely used to discriminate between external memory algorithms on the basis of input/output (I/O) complexity. Parallel algorithms are designed to efficiently utilize the computing power of multiple processing units, interconnected by a communication mechanism. A popular model for developing and analyzing parallel algorithms is the Bulk Synchronous Parallel (BSP) model due to Valiant. In this work we develop simulation techniques, both randomized and deterministic, which produce efficient EM algorithms from efficient algorithms developed under BSP-like parallel computing models. Our techniques can accommodate one or multiple processors on the EM target machine, each with one or more disks, and they also adapt to the disk blocking factor of the target machine. We propose new, more comprehensive models for EM and parallel algorithms which consider the total costs incurred by the algorithm including computation, I/O and communication. The new EM-BSP, EM-BSP*, and EM-CGM models combine the features of the BSP and PDM and thereby answer to a challenge posed by the ACM Working Group on Storage I/O for Large-Scale Computing. We obtain parallel external memory algorithms for a large number of problems including sorting, permutation, matrix transpose, geometric and GIS problems including 3D convex hulls (2D Voronoi diagrams), and various graph problems.
Run-time adjusted congestion control for multimedia: experimental results

Multimedia communications over Internet should achieve adequate quality of service while maintaining 'fairness' in network resources allocation with respect to competing connections. To achieve these conflicting requirements the adopted transport protocol should provide an adequate average throughput and implement congestion control and flow control mechanisms designed to minimize packet loss, delay and throughput variations. The transport protocol proposed here is a modified version of the window-based datagram congestion control protocol, that implements a TCP-like congestion control mechanism wherein the multiplicative decrease of the congestion window is controlled by a non-linear function. Experimental results show that this modified congestion control algorithm, which is adjusted at run-time based on the estimated mean round-trip time, is good candidate toward the aforementioned requirements.
Examining Conversation of Children with Autism Spectrum Disorder (ASD) - An Application of Grice’s Cooperative Principle

This study looks at how individuals with Autism Spectrum Disorder (henceforth ASD) understand messages in a conversation. This study is a case study that focuses on two children with ASD in schools for special needs in Bandung. Applying Grice’s Cooperative Principle, this study examines the observance and nonobservance of maxims as well as the possible reasons underlying the non-observance of maxims by children with ASD. The data which are in the form of texts are obtained from recorded conversations and are analyzed qualitatively. Findings reveal that both children mostly observe all four maxims. However, there are also a small number of instances of non-observance of maxims; namely, flouting, infringing, violating, and opting out that are committed. The reasons behind the non-observance of maxim are, among others, impairment in speaking performance and imperfect command of language. The findings indicate that children with ASD in this context generally manage to create successful communication with their interlocutors. Nevertheless, there are also very rare cases of breaking maxims in which they sometimes make attempts to evoke jokes, avoid uncomfortable situations, and generate other meanings. In fact, these children sometimes fail to produce true and brief utterances due to the characteristics of their language
Validation de la version française d'un questionnaire évaluant les pensées répétitives constructives et non constructives

Abstract This article presents the adaptation and the validation of a shortself-report questionnaire assessing repetitive thinking, the MiniCambridge-Exeter Repetitive Thought Scale (Mini-CERTS). This16 item scale evaluates two dimensions of repetitive thinking:“concrete, experiential thinking” (CET) and “abstract, analyticalthinking” (AAT) that may have constructive and unconstructiveconsequences. A large sample of adult volunteers ( n ! 247) filledin the Mini-CERTS. Subsamples also responded to depression,anxiety and general symptomatology questionnaires as well as to aconcurrent measure, the Ruminative Response Scale. Confirma-tory factor analysis ascertained the two-dimension structure of thequestionnaire. Correlational analyses evidenced differentiated pat-terns of relation between CET and AAT and anxiety, depressionand general symptomatology scales. AAT was correlated to thebrooding scale of the RRS but there was no relation between CETand both scales of the RRS. Preliminary data suggest that theMini-CERTS is sensitive to clinical status and treatment.