Miracle-dz/UniFAR-FTUs huggingface dataset:
Advances in Non-Invasive Brain Computer Interfaces for Control and Biometry

During the last decade many advances in a number of fields have supported the idea that a direct interface between the human brain and an artificial system, called Brain Computer Interface (BCI), is a viable concept, although a significant research and development effort has to be conducted before these technologies enter routine use. The conceptual approach is to model the brain activity variations and map them into some kind of actuation over a target output through the use of signal processing and machine learning methods. In the meantime, several working BCI systems have been described in the literature using a variety of signal acquisition methods, experimental paradigms, pattern recognition approaches and output interfaces, and requiring different types of cognitive activity (Allison et al., 2008; Bashashati et al., 2007; Berger et al., 2008; Leeb et al.‚ 2007; Millan, 2008; Muller-Putz & Pfurtscheller‚ 2008). Nowadays, the principal reason for the BCI research is the potential benefits to those with severe motor disabilities, such as brainstem stroke, amyotrophic lateral sclerosis or severe cerebral palsy (Bensch et al.‚ 2007; Birbaumer et al.‚ 2007; Nijboer et al.‚ 2008; Pfurtscheller et al.‚ 2008). However, the most recent advances in acquisition technology and signal processing assert that controlling certain functions by neural interfaces may have a significant impact in the way people will operate computers, wheelchairs, prostheses, robotic systems and other devices. A very effective way to analyze the brain physiological activity is the electroencephalogram (EEG) measurements from the cortex whose sources are the action potentials of the nerve cells in the brain. The theoretical and the application studies are based on the knowledge that the EEG signals are composed of waves inside the 0-60 Hz frequency band and on the fact that different brain activities can be identified based on the recorded oscillations (Niedermayer & Lopes da Silva, 1999). Over the last years, the interest in extracting knowledge hidden in the EEG signals is rapidly growing, as well as their applications. EEGbased BCIs for motor control and biometry are among the most recent applications in the computational neuro-engineering field. Despite the proof of concept and many encouraging results achieved by some research groups (Marcel & Millan, 2007; Millan et al.‚ 2004; Palaniappan & Mandic, 2007; Pineda, 2005; Pfurtscheller et al., 2006; Vidaurre et al., 2006), additional efforts are required in order to design and implement efficient BCIs. For example, reliable signal processing and pattern recognition techniques able to continuously extract meaningful information from the very noisy EEG is still a high challenge.
Meta-analysis of the Relationship between Mathematics Anxiety and Mathematics Achievement

Bu arastirmada nispeten kucuk orneklemlerden elde edilen veriler uzerinden ogrencilerin Matematik kaygilari ile Matematik basarilari arasindaki iliskiyi inceleyen calismalarin sonuclarinin meta-analiz yoluyla sentezlenmesi amaclanmistir. Bu dogrultuda 2005-2014 yillari arasinda yayinlanmis ve Turkiye baglaminda ogrencilerin Matematik kaygisi ve Matematik basarisi arasindaki iliskiyi inceleyen 11 calisma meta analize dâhil edilmistir. Ilgili arastirmalarin katilimcilari dikkate alindiginda toplamda 8327 kisilik bir orneklem grubundan elde edilen bulgular meta-analiz yontemiyle sentezlenmistir. Meta-analize dahil edilen on bir calismanin tamaminda, matematik kaygisi ve basarisi arasinda istatistiksel acidan anlamli ve negatif yonde iliskiler oldugu gorulmustur. Meta-analiz sonucunda matematik kaygisi ile matematik basarisi arasindaki iliski, Sabit (r=-.39) ve Rasgele (r=-.44) Etkiler Modelleri’ne gore hesaplanmistir. Okul kademesi icin yapilan moderator analizleri sonucunda, ortaokul kademesinde yapilan calismalarda matematik basarisi ve kaygisi arasindaki iliskinin negatif yonde orta duzeyde ve anlamli oldugu gorulmustur. Lise kademesinde yapilan calismalardan elde edilen iliski ise negatif yonde, orta duzeyde ve anlamli bulunmustur. Lise kademesine kiyasla ortaokullarda yapilan arastirmalardan elde edilen iliskilerin etki buyukluklerinin istatistiksel acidan anlamli duzeyde daha yuksek oldugu gorulmustur.
Performance of Site Diversity Investigated Through RADAR Derived Results

Site diversity is an effective rain attenuation mitigation technique, especially in the tropical region with high rainfall rate. The impact of different factors such as site separation distance, frequency, elevation angle, polarization angle, baseline orientation and wind direction is assessed. Results are compared to those reported in existing literature and also compared to the commonly used ITU-R site diversity prediction models. The effect of the wind direction on site diversity is also presented. It can be observed that diversity gain is highly dependent on the site separation distance, elevation angle and wind direction but independent of the frequency, baseline angle and polarization angle of the signal. This study is useful for the implementation of site diversity as a rain attenuation mitigation technique.
Predictive power of psychometric assessments to identify young learners in need of early intervention: data from the Birth to Twenty Plus Cohort, South Africa

The use of psychometric assessments during early childhood to predict children’s later outcomes is vital for early intervention. This study evaluates the predictive power of eight psychometric assessments administered during early childhood as screening measures for identifying those in need of early interventions to prevent late school entry and grade repetition. The measures are the Bayley Scales of Infant Development and the Griffiths Mental Development Scales at 6 months and 1 year; the Vineland Social Maturity Scale and the Behaviour Screening Questionnaire at 2 years and 4 years; the Revised Denver Prescreening Developmental Questionnaire at 5 years; and the Conners’ Teacher Rating Scale, the Draw-a-Person, and the Raven’s Coloured Progressive Matrices at 7 years. We used receiver operating characteristic curve analysis to examine predictive values of the measures, and the area under the curve to assess sensitivity and specificity. Findings suggest that with a moderate degree of diagnostic accuracy, the Bayley Scales of Infant Development at Year 1 with receiver operating characteristic curve (area under the curve = 0.61; 95% confidence interval: 0.51, 0.71) and the Conners’ Teacher Rating Scale at Year 7 with receiver operating characteristic curve (area under the curve = 0.64; 95% confidence interval: 0.58, 0.70) can be used as screening measures to identify children at risk of late school entry. The Conners’ Teacher Rating Scale at Year 7 predicted grade repetition with a moderate degree of accuracy (area under the curve = 0.62; 95% confidence interval: 0.57, 0.67). The only statistically significant covariate-adjusted model showed that young maternal age (β = –5.25; 95% confidence interval: –9.62, –0.88) and low socioeconomic status (β = –2.04; 95% confidence interval: –3.76, –0.33) had a negative influence on the age at school entry as predicted by Bayley Scales of Infant Development at Year 1. This study is the first of its kind in South Africa, and contributes to the conceptual and empirical literature on children’s developmental assessment.
Hepatitis B and C Viruses Infection, Lifestyle and Genetic Polymorphisms as Risk Factors for Hepatocellular Carcinoma in Haimen, China

A case‐control study was carried out to investigate the impact of factors including virus infection, aflatoxin B1, microcystins, smoking/drinking and dietary habits as well as genetic polymorphisms of aldehyde dehydrogenase 2 (ALDH2) and cytochrome P4502E1 (CYP2E1), on susceptibility to hepatocellular carcinoma (HCC) in Haimen, China. A total of 248 patients with HCC and 248 sex‐, age‐ and residence‐matched population‐based controls were recruited into the study. Virus infection, and ALDH2 and CYP2E1 gene polymorphisms were assessed in 134 paired cases and controls. By univariate analysis, hepatitis B virus (HBV) infection (odds ratio [OR]=9.75; 95% confidence interval [CI] =4.71–20.2), history of intravenous injection (OR=1.50; 95%CI=1.02–2.22), average income (OR=0.63; 95% CI=0.43–0.92), frequent intake of foods rich in protein, e.g., egg (OR=0.6; 95% CI=0.42–0.87), chicken (OR=0.53; 95% CI=0.35–0.79), pork (OR=0.67; 95% CI=0.46–0.98) and fresh fish (OR=0.58; 95% CI=0.39–0.87) significantly differed between cases and controls. However, peanut intake (OR=0.66; 95% CI=0.43–1.01), source of drinking water, including tap (OR=1.33; 95% CI=0.81–2.20), deep well (OR=0.94; 95% CI=0.56–1.55), shallow well (OR=0.85; 95% CI=0.55‐–1.30), river (OR=0.95; 95% CI=0.65–1.38), ditch (OR=1.09; 95% CI=0.76–1.55) and pond water (OR=1.0; 95% CI=0.14–7.10) were not significantly associated with risk. Univariate analysis also indicated that the 1–1 genotype of ALDH2 (OR=1.38; 95% CI=0.86–2.23) as well as the Pst1‐ and Rsa1‐digested c1/c1 genotype of CYP2E1 (OR=1.36; 95% CI=0.81–2.28), was slightly more frequent in the case group. On multivariate analysis, HBV infection (OR=13.9; 95% CI=5.78–33.6) and history of intravenous injection (OR=2.72; 95% CI=1.24–6.00) were still associated with significantly increased risk of HCC, while frequent intake of fresh fish (OR=0.32; 95% CI=0.12–0.86) decreased this risk. These findings suggest that whereas peanut intake, water sources as well as genetic polymorphisms in ALDH2 and CYP2E1 do not significantly correlate with the risk of HCC, HBV infection is a main risk factor, and dietary items rich in protein, especially fresh fish, might protect against the risk of HCC in Haimen, China.
Acute attenuation of fatigue after sodium bicarbonate supplementation does not manifest into greater training adaptations after 10-weeks of resistance training exercise

Purpose In two concurrent studies, we aimed to a) confirm the acute effect of 0.3 g·kg-1 body weight (BW) sodium bicarbonate (NaHCO3) supplementation on central and peripheral mechanisms associated with explosive power (Study 1) and b) determine whether chronic NaHCO3 supplementation would improve the adaptive response of the neuromuscular system during a 10-week resistance training program (Study 2). Methods Eight resistance trained participants volunteered after providing written consent. The experimental design consisted of a week of baseline testing, followed by ten weeks of training with progress measures performed in Week 5. Study 1 involved neuromuscular measurements before and after the leg extension portion of a power based training session performed in Week 1. Changes in maximal torque (MVT) and rates of torque development (RTD), along with other variables derived from femoral nerve stimulation (e.g. voluntary activation, neural recruitment) were analysed to determine the extent of fatigue under NaHCO3 or placebo conditions. Changes in these same variables, coupled with functional 1-repetition maximum leg extension strength, were measured in Study 2 from baseline (Week 0) to Week 5, and again at Week 10. Results and conclusion In Study 1, we observed a decline after the leg extension task in both MVT (~ 30%) and rates of torque production (RTD) irrespective of acid-base status, however the decline in maximal RTD (RTDMAX) was nearly 20% less in the NaHCO3 condition when compared to placebo (mean difference of 294.8 ± 133.4 Nm·s-1 (95% CI -583.1 to -6.5 Nm, p < 0.05)). The primary finding in Study 2, however, suggests that introducing NaHCO3 repeatedly during a 10-week RT program does not confer any additional benefit to the mechanisms (and subsequent adaptive processes) related to explosive power production.
Inactivation of O6‐Methylguanine‐DNA Methyltransferase in Human Lung Adenocarcinoma Relates to High‐grade Histology and Worse Prognosis among Smokers

To evaluate the significance of O6‐methylguanine‐DNA methyltransferase (MGMT) activity in the development of human lung adenocarcinoma (AC), we investigated promoter hypermethylation of the MGMTx gene by methylation‐specific PCR, and the expression of MGMT protein by immuno‐histochemistry in relation to smoking history of the patients. In total, 31 of 87 AC patients (35.5%) showed hypermethylation of the MGMT gene, and no significant difference was observed between smokers (37.3%) and non‐smokers (33.3%). However, hypermethylation of the MGMT gene increased in parallel with lesser differentiation grade of tumors among smokers (well, 16.7%; moderately, 42.1%; poorly, 57.1%; P=0.022), although this trend was not observed among non‐smokers. Almost all the tumors with promoter hypermethylation of the MGMT gene showed consistently negative MGMT staining by immunohistochemistry. When the prognosis of stage‐I patients was compared among smokers, it was apparent that the prognosis of patients with inactivated MGMT was worse than that of MGMT‐positive patients (P=0.036). Such differences in the prognoses were not observed among non‐smokers. In conclusion, MGMT inactivation is related to the differentiation grade and the prognosis of lung AC patients among smokers. Although further studies are required, we speculate that smoking may induce hypermethylation, not only of the MGMT gene, but also of other important tumor suppressor genes.
Spatial-Temporal Dynamics of the Sensorimotor Cortex: Sustained and Transient Activity

How the sensorimotor cortex is organized with respect to controlling different features of movement is unclear. One unresolved question concerns the relation between the duration of an action and the duration of the associated neuronal activity change in the sensorimotor cortex. Using subdural electrocorticography electrodes, we investigated in five subjects, whether high frequency band (HFB; 75–135 Hz) power changes have a transient or sustained relation to speech duration, during pronunciation of the Dutch /i/ vowel with different durations. We showed that the neuronal activity patterns recorded from the sensorimotor cortex can be directly related to action duration in some locations, whereas in other locations, during the same action, neuronal activity is transient, with a peak in HFB activity at movement onset and/or offset. This data sheds light on the neural underpinnings of motor actions and we discuss the possible mechanisms underlying these different response types.
The impact of operating system scheduling policies and synchronization methods of performance of parallel applications

Shared-memory multiprocessors are frequently used as compute servers with multiple parallel applications executing at the same time. In such environments, the efficiency of a parallel application can be significantly affected by the operating system scheduling policy. In this paper, we use detailed simulation studies to evaluate the performance of several different scheduling strategies, These include regular priority scheduling, coscheduling or gang scheduling, process control with processor partitioning, handoff scheduling, and affinity-based scheduling. We also explore tradeoffs between the use of busy-waiting and blocking synchronization primitives and their interactions with the scheduling strategies. Since effective use of caches is essential to achieving high performance, a key focus is on the impact of the scheduling strategies on the caching behavior of the applications.Our results show that in situations where the number of processes exceeds the number of processors, regular priority-based scheduling in conjunction with busy-waiting synchronization primitives results in extremely poor processor utilization. In such situations, use of blocking synchronization primitives can significantly improve performance. Process control and gang scheduling strategies are shown to offer the highest performance, and their performance is relatively independent of the synchronization method used. However, for applications that have sizable working sets that fit into the cache, process control performs better than gang scheduling. For the applications considered, the performance gains due to handoff scheduling and processor affinity are shown to be small.
Co-attention CNNs for Unsupervised Object Co-segmentation

Object co-segmentation aims to segment the common objects in images. This paper presents a CNN-based method that is unsupervised and end-to-end trainable to better solve this task. Our method is unsupervised in the sense that it does not require any training data in the form of object masks but merely a set of images jointly covering objects of a specific class. Our method comprises two collaborative CNN modules, a feature extractor and a co-attention map generator. The former module extracts the features of the estimated objects and backgrounds, and is derived based on the proposed co-attention loss which minimizes inter-image object discrepancy while maximizing intra-image figure-ground separation. The latter module is learned to generated co-attention maps by which the estimated figure-ground segmentation can better fit the former module. Besides, the co-attention loss, the mask loss is developed to retain the whole objects and remove noises. Experiments show that our method achieves superior results, even outperforming the state-of-the-art, supervised methods.
Essays on Risk and Uncertainty Preferences

This dissertation sheds a light on risk and ambiguity preferences from different perspectives. Chapter 2 introduces the methods used to investigate risk and ambiguity preferences. Chapter 3 analyzes the stability of ambiguity preferences experimentally, by repeatedly eliciting ambiguity attitudes towards multiple 3-color Ellsberg urns over a period of two months. In the data, 57% of the choices are consistent with stable preferences over the time of observation. This share is significantly higher than random choices would suggest, but significantly lower than the level of consistency in a control treatment without a time lag (71%). Interestingly, for subjects who are able to recall their decision after two months correctly, the share of consistent choices does not drop significantly over time. Recent studies have found correlations between risk attitudes and several sociodemographic characteristics. Chapter 4 deploys an artefactual field experiment to study whether financial professionals and non-professionals are aware of these correlations. The data shows that the subjects are largely able to predict the relationship between demographics and risk attitudes. However, less experienced professionals are significantly more successful in predicting these correlations than senior professionals. Chapter 5 analyzes the prediction of risk preferences of others using an artefactual field experiment with financial professionals and students. For their prediction, the subjects receive information on multiple demographic characteristics and a self-assessment of risk taking of the target. When analyzing the predictions there are three significant effects: Subjects use the demographic information for stereotyping as well as the target's self-assessment on risk taking, and there is a considerable false consensus effect. The false consensus effect is the strongest for experienced professionals. Regarding the prediction's accuracy, the forecasts of the professionals are more accurate than the forecasts of the students. Chapter 6 investigates the effect of social distance on the prediction of risk preferences. As many risky decisions are delegated to professionals, such as financial advisors or doctors. Personal interaction is a common element in such counseling interviews, but also costly for both parties. In times of technological change, it is of interest whether a personal meeting helps to improve the quality of advice. Chapter 5 investigates the assessment of risk preferences of others under two conditions: either the subjects meet personally or make their assessment based only on demographic information. By employing a within-subject design, investigate the prediction accuracy of risk preferences is investigated under both conditions. The results indicate that personal interaction is not a major advantage when assessing the risk preferences of others. Prediction errors remain similar.
Cerebral Blood Flow and Cerebrovascular Reserve Capacity: Estimation by Dynamic Magnetic Resonance Imaging

We have developed a new method for estimation of regional CBF (rCBF) and cerebrovascular reserve capacity on a pixel-by-pixel basis by means of dynamic magnetic resonance imaging (MRI). Thirteen healthy volunteers, 8 patients with occlusion and/or high grade stenosis of the internal carotid artery (ICA), and 2 patients with acute stroke underwent dynamic susceptibility-weighted contrast enhanced MRI. Using principles of indicator dilution theory and deconvolution analysis, maps of rCBF, regional cerebral blood volume, and of the mean transit time (MTT) were calculated. In patients with ICA occlusion/stenosis, cerebrovascular reserve capacity was assessed by the rCBF increase after acetazolamide stimulation. Mean gray and white matter rCBF values in normals were 67.1 and 23.7 mL · 100 g−1 · min−1, respectively. Before acetazolamide stimulation, six of eight patients with ICA occlusions showed decreased rCBF values; and in seven patients increased MTT values were observed in tissue ipsilateral to the occlusion. After acetazolamide stimulation, decreased cerebrovascular reserve capacity was observed in five of eight patients with ICA occlusion. In acute stroke, rCBF in the central core of ischemia was less than 8 mL · 100 g−1 · min−1. In peri-infarct tissue, rCBF and MTT were higher than in unaffected tissue but rCBF was normal. Dynamic MRI provides important clinical information on the hemodynamic state of brain tissue in patients with occlusive cerebrovascular disease or acute stroke.
Evidence of Serial Processing in Visual Word Recognition

To test the limits of parallel processing in vision, we investigated whether people can recognize two words at once. Participants viewed brief, masked pairs of words and were instructed in advance to judge both of the words (dual-task condition) or just one of the words (single-task condition). For judgments of semantic category, the dual-task deficit was so large that it supported all-or-none serial processing: Participants could recognize only one word and had to guess about the other. Moreover, participants were more likely to be correct about one word if they were incorrect about the other, which also supports a serial-processing model. In contrast, judgments of text color with identical stimuli were consistent with unlimited-capacity parallel processing. Thus, under these conditions, serial processing is necessary to judge the meaning of words but not their physical features. Understanding the implications of this result for natural reading will require further investigation.