Miracle-dz/UniFAR-FTUs huggingface dataset:
A Preliminary Analysis of the Logged Questions that Students Ask in Introductory Computer Science

Asking questions is widely believed to contribute to student learning, but little is known about the questions that students ask or how to exploit them in tutorial interventions to help students learn. This paper presents a preliminary analysis of student questions from an introductory computer science course, logged automatically when students requested help during open lab consulting hours. The data set consists of one hundred and forty two questions that introductory computer science students asked while working on four weekly programming assignments. The initial data suggest that student questions can be repetitive in nature and different students ask different kinds of questions. The paper concludes by suggesting that an analysis technique that is more sophisticated than cosine similarity applied to raw text with stop words removed will be necessary to classify student initiated questions.
Transcription‐dependent R‐loop formation at mammalian class switch sequences

Immunoglobulin class switching is mediated by recombination between switch sequences located immediately upstream of the immunoglobulin constant heavy chain genes. Targeting of recombination to particular switch sequences is associated temporally with transcription through these regions. We recently have provided evidence for inducible and stable RNA–DNA hybrid formation at switch sequences in the mouse genome that are mechanistically important for class switching in vivo. Here, we define in vitro the precise configuration of the DNA and RNA strands within this hybrid structure at the Sμ, Sγ3 and Sγ2b mouse switch sequences. We find that the G‐rich (non‐template) DNA strand of each switch sequence is hypersensitive to probes throughout much of its length, while the C‐rich (template) DNA strand is essentially resistant. These results demonstrate formation of an R‐loop, whereby the G‐rich RNA strand forms a stable heteroduplex with its C‐rich DNA strand counterpart, and the G‐rich DNA strand exists primarily in a single‐stranded state. We propose that the organized structure of the R‐loop is essential for targeting the class switch recombination machinery to these sequences.
Visualizing cultural digital resources using social network analysis

This paper describes the design and implementation of a prototype to extract, collect and visually analyse cultural digital resources using social network analysis empowered with semantic features. An initial experiment involved the collection and visualization of connections between cultural digital resources - and their providers - stored in the platform DiCet (an Italian Living Lab centred on Cultural Heritage and Technology). This step helped to identify the most appropriate relational data model to use for the social network visualization phase. We then run a second experiment using a web application designed to extract relevant data from the platform Europeana.eu. The actors in our two-mode networks are Cultural Heritage Objects (CHOs) shared by institutional and individual providers, such as galleries, museums, individual experts and content aggregators. The links connecting nodes represent the digital resources associated to the CHOs. The application of the prototype offers insights on the most prominent providers, digital resources and cultural objects over time. Through the application of semantic analysis, we were also able to identify the most used words and the related sentiment associated to them.
Problems associated with the direct torque control of an interior permanent-magnet synchronous motor drive and their remedies

This paper investigates problems associated with the implementation of a direct torque control (DTC) strategy for an interior permanent-magnet synchronous motor drive. The DTC technique is increasingly drawing attention because of elimination of current controllers and, hence, their inherent delays, and elimination of the rotor position sensor. The latter advantage perhaps is the main impetus for considering this new approach of torque control. Problems associated with this controller, namely, the offset in the current measurements, the stator resistance variation, and the requirement of initial rotor position are addressed in this paper. Ways of mitigating of these problems are also investigated in this paper. These are evaluated with modeling and experimental studies, results of which are also presented.
Generating a neutral point for 3-phase 4-wire DC-AC converters

In this paper, a control strategy is proposed for the neutral point in a 3-phase 4-wire DC-AC power converter. The converter is intended to be connected to 3-phase 4wire loads and/or the power grid. The neutral point can be steadily regulated by a simple controller, involving in voltage and current feedback, even when the three-phase converter system (mostly, the load) is extremely unbalanced. The achievable performance is analyzed quantitatively and the parameters of the neutral leg are determined. Simulations show that the proposed theory is very effective.
Progression of chronic renal disease in humans is associated with the deposition of basement membrane components and decorin in the interstitial extracellular matrix.

The degree of impairment of renal function in patients with chronic renal failure correlates closely with the extent of fibrosis in the tubulointerstitium, i.e. of interstitial extracellular matrix (ECM) accumulation. The composition of this pathological extracellular matrix and the relation between the ECM composition on the one hand and the severity of histological changes and renal function on the other has not been investigated. This prompted us to perform the present study. The severity of histological abnormalities and the composition of the interstitial ECM were assessed using a semiquantitative scoring technique in 57 biopsies from patients with kidney disease of diverse etiology and variable degrees of renal failure and were contrasted with the results of 9 control biopsies. Tissue sections were stained with an indirect immunoperoxidase technique using antibodies against collagen I, III, IV, V, VI, laminin, fibronectin, decorin and heparansulphate proteoglycan core protein (HSPG). Collagen IV, laminin and HSPG were virtually absent from the interstitium in controls. These components were more widely distributed in patients and the extent of their deposition correlated with the severity of interstitial histological abnormalities. In patients with severe interstitial damage the deposition became diffuse. Collagen type I and III were already diffusely distributed in the interstitium of controls and did not increase significantly as interstitial damage became more severe. However, the extent of collagen III staining in patients was significantly higher than in controls. Decorin staining showed a patchy distribution both in patients and controls. The overall distribution was significantly increased in patients. The extent of the deposition of both collagen V and VI was significantly increased in patients when compared with controls. Only the distribution of collagen V correlated with the severity of histological abnormalities. Our findings suggest that an increased interstitial deposition of extracellular matrix substances which are generally regarded as basement membrane components contributes more to the development of interstitial fibrosis and renal failure than the deposition of the fiber forming interstitial collagens type I and III, which are prominent in controls and in patients irrespective of the severity of histological abnormalities. Decorin staining was significantly enhanced in patients and was found to be the best predictor both of the severity of interstitial fibrosis and of renal failure. This could mean that decorin is important in human renal pathology. Collagen V and VI staining was significantly increased in patients when compared with controls. To our knowledge this is the first study in which this is demonstrated.
Factors influencing dialysis arteriovenous graft survival

Purpose Dysfunction and loss of patency of dialysis arteriovenous grafts (AVGs) are serious causes of morbidity in patients on dialysis. Various risk factors associated with shorter AVG patency have been blamed, but the results of the studies were controversial. The aim of this study was to assess if associated diseases, biochemical markers and other parameters associated with atherosclerosis influence patency of AVGs in a large vascular access centre. Methods We conducted a retrospective study that included patients with AVGs patent for at least 3 weeks after creation. We included variables associated with atherosclerosis into the analysis (coronary artery disease, diabetes mellitus, chronic heart failure, arterial hypertension, smoking history and cholesterol and triglyceride levels) and characteristics of the graft (shape, feeding artery). The data was assessed using log-rank (Cox-Mantel) test. The differences were shown using Kaplan-Meier graphs. The observation period was limited to 1000 days after access creation. Results Overall, 338 patients were included in the study. Significantly higher risk of access failure was associated with presence of coronary artery disease (p = 0.0035). Higher serum cholesterol levels were associated with longer survival of the graft in 1000 days of surveillance (p = 0.04). Conclusions Coronary artery disease negatively influences the cumulative patency of vascular access. Higher serum cholesterol levels are associated with lower AVG failure risk over a 1000-day period, which probably corresponds to the worse disease status of the patients with lower cholesterol values.
WCE video segmentation using textons

Wireless Capsule Endoscopy (WCE) integrates wireless transmission with image and video technology. It has been used to examine the small intestine non invasively. Medical specialists look for signicative events in the WCE video by direct visual inspection manually labelling, in tiring and up to one hour long sessions, clinical relevant frames. This limits the WCE usage. To automatically discriminate digestive organs such as esophagus, stomach, small intestine and colon is of great advantage. In this paper we propose to use textons for the automatic discrimination of abrupt changes within a video. In particular, we consider, as features, for each frame hue, saturation, value, high-frequency energy content and the responses to a bank of Gabor filters. The experiments have been conducted on ten video segments extracted from WCE videos, in which the signicative events have been previously labelled by experts. Results have shown that the proposed method may eliminate up to 70% of the frames from further investigations. The direct analysis of the doctors may hence be concentrated only on eventful frames. A graphical tool showing sudden changes in the textons frequencies for each frame is also proposed as a visual aid to find clinically relevant segments of the video.
Non-piont source pollution and stormwater management practices of parking lot

As one of the urban infrastructure, parking lot holds a large proportion in the urban impervious area. Characteristics of parking lots and their negative effects to environment ware analyzed. The main pollutants in parking lot runoff and the event mean concentration of those pollutants ware listed. Representative stormwater management technologies in parking lot ware introduced, such as permeable pavements, grass swale and rain garden. A case study of retrofits in parking lot was presented briefly. It was pointed out that new stormwater management practices should be adapted to the design and construction of parking lot, and the resource-saving and environment-friendly parking lot incorporated with stormwater management practices should be established as soon as possible in Chinese cities.
Variability and distribution of muscle strength and its determinants in humans

Introduction: Inter‐individual variability in measurements of muscle strength and its determinants was identified to: (1) produce a normative data set describing the normal range and (2) determine whether some measurements are more informative than others when evaluating inter‐individual differences. Methods: Functional and morphological characteristics of the vastus lateralis were measured in 73 healthy, untrained adult men. Results: Inter‐individual variability (coefficient of variation) was greater for isometric maximal voluntary contraction (MVC) torque (18.9%) compared with fascicle force (14.6%; P = 0.025) and physiological cross‐sectional area (PCSA; 17.2%) compared with anatomical cross‐sectional area (ACSA, 13.0%; P < 0.0005). The relationship between ACSA and isometric MVC torque (r2 = 0.56) was weaker than that between PCSA and fascicle force (r2 = 0.68). Conclusions: These results provide a normative data set on inter‐individual variability in a variety of muscle strength‐related measurements and illustrate the benefit of using more stringent measures of muscle properties. Muscle Nerve 49: 879–886, 2014
Introducing a New Database of Sovereign Defaults

Until recently, there have been few efforts to systematically measure and aggregate the nominal value of the different types of sovereign government debt in default. To help fill this gap, the Bank of Canada’s Credit Rating Assessment Group (CRAG) has developed a comprehensive database of sovereign defaults posted on the Bank of Canada’s website. Our database draws on previously published data sets compiled by various official and private sector sources. It combines elements of these, together with new information, to develop estimates of stocks of government obligations in default, including bonds and other marketable securities, bank loans, and official loans in default, valued in U.S. dollars, for the years 1975 to 2013 on both a country-by-country and a global basis. CRAG’s new database, and subsequent updates, will be useful to researchers analyzing the economic and financial effects of individual sovereign defaults and, importantly, the impact on global financial stability of episodes involving multiple sovereign defaults.
Antibacterial activity of diacetylcurcumin against Staphylococcus aureus results in decreased biofilm and cellular adhesion

Purpose. Staphylococcus aureus infections have contributed to the global healthcare burden, particularly with regard to hospital‐acquired meticillin‐resistant S. aureus (MRSA) infections. Methodology. This study describes the antibacterial activity of diacetylcurcumin (DAC) against meticillin‐susceptible S. aureus/MRSA biofilm formation, survival, metabolic activity and structure; its ability to prevent bacterial adhesion to human cells; and toxicity in Galleria mellonella larvae. Results. DAC showed excellent antibacterial activity, with MIC ranging between 17.3 and 34.6 &mgr;mol l−1, and minimum bactericidal concentration ranging between 69 and 277 &mgr;mol l−1. It significantly reduced bacterial biofilm survival ‐ by 22‐63% (at MIC, 10×MIC or 100×MIC) as compared to the 25‐42% reduction by vancomycin (P<0.0001) ‐ and severely affected biofilm cell structures, leading to damaged architecture and the formation of amorphous cell clusters. Treatment with DAC (MIC/4) decreased bacterial adhesion to HaCaT keratinocytes from 1 to 5 h (P<0.0001). Finally, DAC demonstrated low toxicity in G. mellonella at its effective anti‐biofilm concentrations. Conclusion. These findings open new avenues for the study of this curcumin derivative as an excellent prototype with anti‐MRSA activity.
Interleaved snapshot echo planar imaging of mouse brain at 7.0 T

Single‐shot echo planar imaging (EPI) of a mouse brain at high field is very challenging. Large susceptibility‐induced gradients affect much of the brain volume, causing severe image deformations and signal loss. Segmented EPI and other conventional multi‐shot approaches alleviate these problems but suffer from lower temporal resolution and motion artifacts. We demonstrate that interleaved snapshot EPI represents a simple and robust alternative approach and one that is particularly suitable for high‐field T2*‐weighted functional imaging of a mouse brain. Similarly to segmented multi‐shot techniques, it significantly reduces the susceptibility‐related artifacts. At the same time, it preserves the high temporal resolution and the snapshot capability of a conventional EPI by acquiring entire image within a single TR period. We discuss implementation details of the interleaved snapshot EPI sequence and the trade‐offs involved between the imaging efficiency, the number of interleaved excitation‐acquisition blocks and the artifact reduction. To document the sequence utility, murine brain in vivo imaging with the interleaved snapshot EPI method was compared with a conventional EPI. We found that at least five interleaved blocks were necessary to restore the signal in most cortical areas. We also show that a standard global shimming procedure provides sufficient homogeneity for multi‐slice interleaved snapshot EPI acquisition. In contrast, the conventional EPI of comparable image quality would be limited to a single slice with highly optimized local shim. Finally, an in vitro comparison with turbo FLASH acquisition shows the interleaved snapshot EPI to have superior time resolution and signal‐to‐noise ratio. Copyright © 2006 John Wiley & Sons, Ltd.
„EEG-basierende Kommunikation” - ein neues Konzept zur rehabilitativen Unterstützung von Patienten mit schwerer motorischer Beeinträchtigung

Institutsangaben 1 Ludwig-Boltzmann Institut f r Medizinische Informatik und Neuroinformatik, Technische Universit t Graz 2 Abteilung f r Medizinische Informatik, Institut f r Elektround Biomedizinische Technik, Technische Universit t Graz 3 Beratungsstelle f r unterst tzte Kommunikation und elektronische Hilfen (BUK), Rehabilitationszentrum Bethesda, kreuznacher diakonie, Bad Kreuznach 4 Institut f r Medizinische Psychologie und Verhaltensneurobiologie, Universit t T bingen 5 Center for Cognitive Neuroscience, University of Trento, Italien
HYPERTENSION IN HEMODIALYSIS PATIENTS: Hypertension Control with Daily Dialysis

Hypertension is present in 60–90% of patients on maintenance hemodialysis (HD) and it is an important cause of cardiovascular (CV) mortality and morbidity. Frequent and prolonged HD has been uniformly shown to control hypertension in end‐stage renal disease (ESRD) patients more effectively than conventional HD. The etiology of hypertension is predominantly volume dependent, but in a subset of patients increased renin, sympathetic overactivity, and endothelial dysfunction may play a role. Intradialytic hypotension precludes attainment of dry weight and hence optimal control of hypertension in conventional HD is challenging. Frequent and prolonged dialysis with gentle and persistent ultrafiltration allows time for refilling of the intravascular compartment and permits normalization of extracellular volume. It is also possible that intensive dialysis enables removal of pressor molecules and improves endothelial function. Improved blood pressure control translates into regression of left ventricular hypertrophy in patients on daily HD. Thus prolonged and frequent dialysis permits better control of hypertension via volume and volume‐independent mechanisms and also improves cardiac geometry.
UHF tag for suitcase RFID application in airports

This paper presents a passive UHF tag configuration for suitcase security and tracking in airport luggage operation. The proposed solution is based on conformal geometry tag, consisting of a folded dipole with orthogonal arms, appropriate for integration into the wall of injection moulded suitcases during its fabrication process. The ALIEN Higgs-2 integrated circuit is used. Simulated frequency dependence of the proposed UHF passive tag is presented and maximum detection range was measured in free space and within the suitcase in several test environments. The experimental results are compared with a commercial tag and demonstrate good agreement with predictions.
Insurer Risk Management and Shareholder Wealth

We derive the financial market return implications of a number of models of an insurer faced with different regulatory regimes and differing access to financial markets for added capital. If insurers have unhindered access to financial markets and insurance regulation requires an immediate capital contribution to offset a capital deficit, then capital volatility has no impact on insurer equity market returns. In an unregulated insurance market, regardless of access to financial markets, greater volatility reduces expected insurer equity market returns. Finally, in a regulated and capital constrained insurance market, where transactions costs prevent insurers from obtaining financial market capital contributions, greater capital volatility increases expected insurer equity market returns. In empirical testing, we find that volatility decreases the equity market returns of property-liability insurers. This result is consistent with imperfect insurance regulation and policyholders who bear the risk of insurer financial distress with incomplete compensation. In this environment, insurer risk management decreases shareholder wealth because it decreases the likelihood that insurers share financial distress with policyholders.
International Real Business Cycles , Portfolio Diversi cation and Valuation E ¤ ects

This paper presents an international real business cycle model in the spirit of Backus, Kehoe, and Kydland (92) with endogenously determined portfolio allocations under incomplete markets. It jointly studies the properties of the portfolio side of the economy, which includes the valuation e¤ects, asset returns and portfolio allocations, along with the more typical international macro variables. The model generates a substantial portfolio home bias, which is dependent on the combination of the consumption home bias parameter and the elasticity of substitution between domestic and foreign traded goods. A higher level of consumption bias determines a higher level of portfolio bias, but the elasticity of substitution must be small in order for the result to hold. The home asset is a good hedge against movements of international prices, which make home physical capital lose value in response to productivity shocks. Using productivity and demand shocks, the model generates also an adequate amount of assetsvaluations, which drives the distinction between accounting current account and changes in the net foreign asset position of a country, but does not resolve the Backus-Smith puzzle for standard parameterizations. Adding a further shock to investment absorption does not help in this respect either. JEL Classi cation: E32, F32, F41, G11 Keywords: Business Cycles, Open Economy, DSGE, Portfolio Diversi cation