Miracle-dz/UniFAR-FTUs huggingface dataset:
Long-term monitoring in IC4665: fast rotation and weak variability in very low mass objects

We present the combined results of three photometric monitoring campaigns targeting very low mass (VLM) stars and brown dwarfs in the young open cluster IC4665 (age ∼40 Myr). Each of our observing runs covers time-scales of ∼5 d in the seasons 1999, 2001 and 2002, respectively. In all three runs, we observe ∼100 cluster members, allowing us for the first time to put limits on the evolution of spots and magnetic activity in fully convective objects on time-scales of a few years. For 20 objects covering masses from 0.05 to 0.5 M ⊙ , we detect a periodic flux modulation, indicating the presence of magnetic spots co-rotating with the objects. The detection rate of photometric periods (∼20 per cent) is significantly lower than in solar-mass stars at the same age, which points to a mass dependence in the spot properties. With two exceptions, none of the objects exhibits variability and thus spot activity in more than one season. This is contrary to what is seen in solar-mass stars and indicates that spot configurations capable of producing photometric modulations occur relatively rarely and are transient in VLM objects. The rotation periods derived in this paper range from 3 to 30 h, arguing for a lack of slow rotators among VLM objects. The periods fit into a rotational evolution scenario with pre-main sequence contraction and moderate (40-50 per cent) angular momentum losses due to wind braking. By combining our findings with literature results, we identify two regimes of rotational and magnetic properties, called C- and I-sequence. Main properties on the C-sequence are fast rotation, weak wind braking, Hα emission and saturated activity levels, while the I-sequence is characterized by slow rotation, strong wind braking, no Hα emission and linear activity-rotation relationship. Rotation rate and stellar mass are the primary parameters that determine in which regime an object is found. We outline a general scheme to understand rotational evolution for low-mass objects in the context of these two regimes and discuss the potential as well as the problems of this picture.
Financial time series forecasting with machine learning techniques: a survey

Stock index forecasting is vital for making informed investment decisions. This paper surveys recent literature in the domain of machine learning techniques and artificial intelligence used to forecast stock market movements. The publications are categorised according to the machine learning technique used, the forecasting timeframe, the input variables used, and the evaluation techniques employed. It is found that there is a consensus between researchers stressing the importance of stock index forecasting. Artificial Neural Networks (ANNs) are identified to be the dominant machine learning technique in this area. We conclude with possible future research directions.
Nonalcoholic Cirrhosis Increased Risk of Digestive Tract Malignancies

AbstractAlcoholic cirrhosis is generally accepted as a risk factor for hepatocellular carcinoma (HCC) development; however, little research has examined the relationship between nonalcoholic cirrhosis (NAC) and HCC. Thus, the aim of this study was to investigate whether NAC is associated with the risk of HCC and extrahepatic malignancies in Taiwan.We conducted a populated-based retrospective cohort study by using data from the Taiwan National Health Insurance (NHI) program. A total of 2109 patients with NAC were identified from the NHI database between 2000 and 2011. For a control group, 4 patients without NAC were frequency-matched with each NAC patient according to sex, age, and index year. We used Cox proportional hazards regression analysis to calculate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) and determine the effects of NAC on cancer risk.The overall cancer risk was significantly higher in patients with NAC compared with those without NAC, and this association was consistent among age, sex, and comorbidity groups. The risk of developing HCC was remarkably high in the NAC group compared with in the control cohort (aHR = 122.7, 95% CI = 68.4–220.1); significantly higher risks of extrahepatic malignancies were observed in patients with digestive tract cancers and hematological malignancies. Further analyses stratified according sex, age, and follow-up duration revealed various patterns among the cancer types.The results indicate that patients with NAC in Taiwan have higher risks of HCC, digestive tract cancers, and hematological malignancies.
Optimal Risk Sharing in the Presence of Moral Hazard under Market Risk and Jump Risk

This paper provides a tractable framework to study optimal risk sharing between an investor and a firm with general utility forms in the presence of moral hazard under market risk and jump risk. We show that, for a two-date discrete-time moral hazard model, there exists a continuous-time model that obtains the same optimal result. Moreover, we characterize the optimal risk sharing explicitly, in particular, the structural effect of jump risk on the optimal allocations.
Biomagnetic detection of gastric electrical activity in normal and vagotomized rabbits

We recorded the vector magnetogastrogram (MGG) due to gastric electrical activity (GEA) in normal rabbits using a Superconducting QUantum Interference Device (SQUID) magnetometer and measured the degree of correlation of the MGG with 24 channels of serosal electrodes. The vector magnetometer allows us to non‐invasively record three orthogonal magnetic field components and project the recorded magnetic field vector into arbitrary directions. We optimized the magnetic field vector direction to obtain the highest possible correlation with each serosal electrode recording. We performed a vagotomy and examined spatial and temporal changes in the serosal potential and in the transabdominal magnetic field. We obtained spatial information by mapping the recorded signals to the electrode positions in the gastric musculature. Temporal evidence of uncoupling was observed in spectral analyses of both serosal electrode and SQUID magnetometer recordings. We conclude that non‐invasive recordings of the vector magnetogastrogram reflect underlying serosal potentials as well as pathophysiological changes following vagotomy.
Exploiting high-level descriptions for circuits fault tolerance assessments

The paper proposes a new approach to estimate early the fault detection capability of a safety-critical computer-based system from its high-level description. This paper first aims at verifying the correspondence between dependability measures obtained through simulation-based fault injection experiments at different levels of abstraction. Then, we propose Alternative Graphs (AGs) to create lists of malicious faults without expanding the full data flow, whose size can often explode. Fault trees are exploited to improve the results of the high-level fault analysis. To evaluate the effectiveness of the approach, simulation-based fault injection experiments have been done on some benchmark systems described in VHDL language. The approach demonstrates that fault detection analysis performed at a high-level is less CPU time demanding but approximates well the fault detection measures achievable on a low-level system description.
Security Paradigms for Cloud Computing

Cloud Computing -- some treat it as a catchphrase, others as the next step in evolution of their organization and the Internet. However, what is for sure is that, it is a way of leveraging less expensive services based environment providing cost-effective solutions to various organizations to cater for their computing needs, without investing in computing infrastructure. However, cloud computing, just like other formats of computing, is not free from issues. One of the major barriers in adoption of cloud is security. Once migrated to cloud, you do not know where your data is physically stored, what laws and regulations govern the same and most important of all, who has access to it. This paper explores security issues related to cloud computing and proposes a paradigm for securing cloud. The paper investigates some of the key research challenges of implementing cloud-aware security solutions which can plausibly secure the ever-changing and dynamic cloud environment, followed by conclusion where we try to entail the whole research and try to formulate a practical security paradigm, which will enable the cloud providers and consumers to ensure that their data and valuable assets are safe from otherwise prying eyes.
Oceanic and atmospheric anomalies of tropical instability waves

Tropical instability waves (TIWs) are detected in remotely‐sensed sea surface height (SSH), temperature (SST), and wind records of the eastern equatorial Pacific. Analyses of TIW anomaly relationships reveal strong dynamical influence of TIWs within approximately 5° of the equator. The first influence is advective heat flux. The primary forcing of TIW SST anomalies is advection of the meridional temperature gradient by TIW currents. The second influence is modification of the wind stress and Ekman pumping fields by TIW surface ocean currents. By affecting surface stress and hence roughness, TIW currents in this low‐wind region introduce a significant bias in scatterometer vector wind measurement. This bias is evident in both NSCAT and QuikSCAT winds. The difference between wind measurements from TAO moorings and scatterometers is phase‐locked with TIW SST oscillations. These results have important implications for scatterometry and for understanding tropical dynamics, thermodynamics and biogeochemistry.
Enhanced 4-Hydroxynonenal Resistance in KEAP1 Silenced Human Colon Cancer Cells

Nuclear factor erythroid 2-related factor 2 (NRF2) is the transcription factor that regulates an array of antioxidant/detoxifying genes for cellular defense. The conformational changes of Kelch-like ECH-associated protein 1 (KEAP1), a cytosolic repressor protein of NRF2, by various stimuli result in NRF2 liberation and accumulation in the nucleus. In the present study, we aimed to investigate the effect of KEAP1 knockdown on NRF2 target gene expression and its toxicological implication using human colon cancer cells. The stable KEAP1-knockdown HT29 cells exhibit elevated levels of NRF2 and its target gene expressions. In particular, the mRNA levels of aldo-keto reductases (AKR1C1, 1C2, 1C3, 1B1, and 1B10) were substantially increased in KEAP1 silenced HT29 cells. These differential AKRs expressions appear to contribute to protection against oxidative stress. The KEAP1-knockdown cells were relatively more resistant to hydrogen peroxide (H2O2) and 4-hydroxynonenal (4HNE) compared to the control cells. Accordantly, we observed accumulation of 4HNE protein adducts in H2O2- or 4HNE-treated control cells, whereas KEAP1-knockdown cells did not increase adduct formation. The treatment of KEAP1-silenced cells with AKR1C inhibitor flufenamic acid increased 4HNE-induced cellular toxicity and protein adduct formation. Taken together, these results indicate that AKRs, which are NRF2-dependent highly inducible gene clusters, play a role in NRF2-mediated cytoprotection against lipid peroxide toxicity.
Selfie-taking motives and social psychological dispositions as predictors of selfie-related activities among university students in Kuwait

This study explores motives for taking and posting selfies on social media and whether those motives and other social psychological dispositions predict the selfie-related activities of “taking,” “posting,” and “editing” selfies. A sample of 404 university students in Kuwait indicated they took and posted selfies for motives of appraisal-seeking self-presentation (ASSP), entertainment, status-updating self-presentation (SUSP) and documentation. Females were more likely to be involved in selfie-related activities and to use selfies for ASSP. Documentation was the prime predictor of the activity of “taking” selfies, SUSP was for “posting” selfies, and ASSP was for “editing” selfies. Self-perceived attractiveness predicted the activities of “posting” and “taking” selfies. Results are discussed in light of the influence of culture in Kuwait and some conceptual considerations about selfies are made.
Reduced Excitatory Drive onto Interneurons in the Dentate Gyrus after Status Epilepticus

Impaired GABAergic inhibition may contribute to the development of hyperexcitability in epilepsy. We used the pilocarpine model of epilepsy to demonstrate that regulation of excitatory synaptic drive onto GABAergic interneurons is impaired during epileptogenesis. Synaptic input from granule cells (GCs), perforant path, and CA3 inputs onto hilar border interneurons of the dentate gyrus were examined in rat hippocampal slices during the latent period (1–8 d) after induction of status epilepticus (SE). Short-term depression (STD) of GC inputs to interneurons induced by brief (500–800 msec), repetitive (5–20 Hz) stimulation, as well as paired-pulse depression at both GC and CA3 inputs to interneurons, were significantly (p < 0.05) enhanced in SE-experienced rats. In contrast, we found no significant differences between SE-experienced and age-matched control rats in the properties of minimal EPSCs evoked at low frequency (0.3 Hz). Consistent with reduced GABAergic inhibition onto granule cells, paired-pulse depression of perforant path-evoked granule cell population spikes was lost in SE-experienced rats. Enhanced STD was partially mediated by group II metabotropic glutamate receptors, because the selective antagonist, 2S-2-amino-2-(1S,2S-2-carboxycyclopropyl-1-yl)-3-(xanth-9-yl)propanoic acid, attenuated STD in SE-experienced rats but had no effect on STD of GC inputs in the normal adult rat. The group II mGluR agonist, (2S′,1R′,2R′,3R′)-2-(2,3-dicarboxylcyclopropyl) glycine (1 μm), produced a greater depression of GC input to hilar border interneurons in SE-experienced rats than in controls. These results indicate that, in the SE-experienced rat, excitatory drive to hilar border inhibitory interneurons is weakened through a use-dependent mechanism involving group II metabotropic glutamate receptors.
Dictionary Learning for Sparse Approximations With the Majorization Method

In order to find sparse approximations of signals, an appropriate generative model for the signal class has to be known. If the model is unknown, it can be adapted using a set of training samples. This paper presents a novel method for dictionary learning and extends the learning problem by introducing different constraints on the dictionary. The convergence of the proposed method to a fixed point is guaranteed, unless the accumulation points form a continuum. This holds for different sparsity measures. The majorization method is an optimization method that substitutes the original objective function with a surrogate function that is updated in each optimization step. This method has been used successfully in sparse approximation and statistical estimation [ e.g., expectation-maximization (EM)] problems. This paper shows that the majorization method can be used for the dictionary learning problem too. The proposed method is compared with other methods on both synthetic and real data and different constraints on the dictionary are compared. Simulations show the advantages of the proposed method over other currently available dictionary learning methods not only in terms of average performance but also in terms of computation time.
The relationship between age of air and the diabatic circulation of the 1 stratosphere 2

The strength of the Brewer–Dobson circulation is difficult to estimate using observations. Trends in the age of stratospheric air, deduced from observations of transient tracers, have been used to identify trends in the circulation, but there are ambiguities in the relationship between age and the strength of the circulation. This paper presents a steady–state theory and a time–dependent extension to relate age of air directly to the diabatic circulation of the stratosphere. In steady state, it is the difference between the age of upwelling and downwelling air through an isentrope and not the absolute value of age that is a measure of the strength of the diabatic circulation through that isentrope. For the time–varying case, expressions for other terms that contribute to the age budget are derived. An idealized atmospheric general circulation model with and without a seasonal cycle is used to test the time–dependent theory and to find that these additional terms are small upon annual averaging. The steady–state theory holds as well for annual averages of a seasonally–varying model as for a perpetual solstice model. These results are a step towards using data to quantify the strength of the diabatic circulation. 16
Genetic and Epigenetic Modifications of Sox2 Contribute to the Invasive Phenotype of Malignant Gliomas

We undertook this study to understand how the transcription factor Sox2 contributes to the malignant phenotype of glioblastoma multiforme (GBM), the most aggressive primary brain tumor. We initially looked for unbalanced genomic rearrangements in the Sox2 locus in 42 GBM samples and found that Sox2 was amplified in 11.5% and overexpressed in all the samples. These results prompted us to further investigate the mechanisms involved in Sox2 overexpression in GBM. We analyzed the methylation status of the Sox2 promoter because high CpG density promoters are associated with key developmental genes. The Sox2 promoter presented a CpG island that was hypomethylated in all the patient samples when compared to normal cell lines. Treatment of Sox2-negative glioma cell lines with 5-azacitidine resulted in the re-expression of Sox2 and in a change in the methylation status of the Sox2 promoter. We further confirmed these results by analyzing data from GBM cases generated by The Cancer Genome Atlas project. We observed Sox2 overexpression (86%; N = 414), Sox2 gene amplification (8.5%; N = 492), and Sox 2 promoter hypomethylation (100%; N = 258), suggesting the relevance of this factor in the malignant phenotype of GBMs. To further explore the role of Sox2, we performed in vitro analysis with brain tumor stem cells (BTSCs) and established glioma cell lines. Downmodulation of Sox2 in BTSCs resulted in the loss of their self-renewal properties. Surprisingly, ectopic expression of Sox2 in established glioma cells was not sufficient to support self-renewal, suggesting that additional factors are required. Furthermore, we observed that ectopic Sox2 expression was sufficient to induce invasion and migration of glioma cells, and knockdown experiments demonstrated that Sox2 was essential for maintaining these properties. Altogether, our data underscore the importance of a pleiotropic role of Sox2 and suggest that it could be used as a therapeutic target in GBM.
The effect of adult attachment on intrusive imagery

This thesis is concerned with intrusive imagery within psychological disorders, and the study of this in relation to attachment theory. Part one is a narrative literature review of direct imagery interventions, such as imaginal exposure and imagery rescripting, for psychological disorders that are not post-traumatic stress disorder or acute stress disorder. This review serves as a reference guide for clinicians to help them navigate the literature on imagery interventions. Part two is an experimental study using a paired-associate methodology to investigate the association between attachment orientation and the experience of intrusive and involuntary imagery. This study elicits involuntary imagery within a laboratory context with members of the general population. Part three is a critical appraisal of the thesis process that reflects upon research processes with reference to the broader context of clinical psychology in general.
Personalized mobile application discovery

With the dramatic growing of mobile application markets, users can find apps with any function they desire in these markets. However, the huge amounts of apps make it quite a challenge for users to discover good applications efficiently. Previous studies recommend applications based on the download history, user ratings or app usage records. Most of these studies fail to capture users' personal interests in mobile applications precisely. In this paper, we leverage apps as features for describing user's personal interests and propose a novel approach to do personalized recommendation. We introduce a Small-Crowd model to distinguish apps at reflecting users' personal interests, and design a weighting method to rank the installed apps for users by combining the global download information with fine-grained app usage records. The extensive experiments validate the effectiveness of our approach which outperforms state-of-the-art method.
Fundamental frequency as basis for speech segmentation modeling

The present study investigates the relevance of fundamental frequency in speech segmentation models intended to simulate infants. Speech from three different conditions (infant-directed speech to 3- and 12-month-olds, and adult-directed speech) was segmented based on fundamental frequency information, using a variant of the dpn-gram segmenting technique (highlighting similar segments as lexical candidates). The spectral distance between segments that were found based on fundamental frequency similarity was calculated, and compared to the spectral distance between segments that were found using transcription as basis for segmentation, as well as to the spectral distance between randomly paired segments from the same speech materials. The results show the greatest within-condition difference in speech directed to 3-month-olds, in which segmenting based on fundamental frequency similarity generated segment pairs with smaller spectral distance than did transcription-based segmentation or random segment pairs. Speech directed to 12-month-olds resulted in a somewhat smaller difference when using fundamental frequency data compared to when using transcriptions. For adult-directed speech, no difference was found in spectral distance between pairs generated by the different bases for segmentation. Neither segmenting speech by highlighting similar segments as lexical candidates, nor using fundamental frequency as basis for segmentation is optimal for a speech segmentation model intended to simulate 12-month-olds or adults. These groups are more likely to segment speech based on their already present or growing linguistic experience than on acoustic similarity only. However, for a model simulating a 3-month-old infant, the present segmentation procedure and its basis for segmentation are more plausible. When modeling speech segmentation in an infant-like manner it is important to take into account both that the cognitive abilities of infants develop rapidly during the first year of life, and that some aspects of their linguistic environment vary during this period.
Effects of Time Pressure on the Phonetic Realization of the Dutch Accent-Lending Pitch Rise and Fall

Abstract The goal of this experiment is to find the most important phonetic features of Dutch accent-lending pitch movements, in terms of shape, pitch level and alignment with the segmental structure. Time pressure is used as a heuristic method to isolate important phonetic aspects of pitch movements, assuming that under time pressure the speaker will preserve those aspects. In a production experiment, accent-lending rises (‘l’) and falls (‘A’) were realized under various types of time pressure. The pitch rise is time-compressed under all pressure types, which would mean that the shape of the rise is relatively unimportant. The segmental alignment of the rise proved to be more important: the onset of the rise is synchronized with the syllable onset. For the fall no fixed synchronization point was found, but its shape was relatively invariant, indicating that shape rather than exact timing is the more important feature of the fall.