Miracle-dz/UniFAR-FTUs huggingface dataset:
Journal of Graph Algorithms and Applications the Complexity of the Simultaneous Cluster Problem

We study clustering over multiple graphs-each encoding a distinct set of similarity relationships (edges) over the same set of objects (nodes)-where the aim is to identify clusters that are supported across the collection of graphs. This problem of simultaneous clustering is readily motivated by the recent deluge of datasets in several domains (including the biological sciences, social sciences, and marketing), where the same objects are repeatedly measured in different conditions, populations or time points. Whilst there has been a vast amount of heuristic work on practical simultaneous clustering problems, little is known on the theoretical side – we present theoretical results that help explain why such heuris-tics typically come without quantitative guarantees. We give algorithmic and complexity results for simultaneous clustering using two standard measures on clustering quality: density and connectivity. Specifically, we focus on the basic problem of finding a single cluster (rather than an entire clustering) that is simultaneously of high quality in every graph. When the quality of a cluster is its minimum density over all graphs, we show the problem is not approximable within a factor of 2 log 1−ε n , unless N P ⊆ DT IM E(n polylogn). Furthermore, this problem appears very difficult even when there are just two graphs; the resulting problem is approximately as hard as the problem of finding a dense subgraph on at most k vertices. When cluster quality is a fixed connectivity requirement between terminals within the cluster, there are two natural optimization problems: a maximization version (find a good quality cluster with as many terminals as possible) and a minimization version (find a good quality cluster that is as small as possible). We show that the maximization problem is tractable in polynomial time for any fixed connectivity requirement k. On the other hand the minimization problem is hard to approximate within a factor of 2 log 1−ε n , unless N P ⊆ DT IM E(n polylogn). The number of graphs in our reduction depends on n. If instead the number of graphs is fixed, we show there is an ε > 0 for which the minimization problem is not approximable within g 1/2−ε for any fixed number g of graphs unless N P = ZP P. These hardness results for the minimization problem hold even in the simple cases where the connectivity requirement is one and there are either just two terminal nodes or every node …
Endoscopic third ventriculostomy in treatment of hydrocephalus

Introduction Endoscopic third ventriculostomy (ETV) is a minimally invasive method of treatment of obstructive hydrocephalus (HCP). Aim To investigate perioperative and intraoperative difficulties, failures and complications of ETV. Material and methods Seventy-three procedures of ETV were conducted in our department in the last 5 years on 69 patients with HCP of different etiology. In 4 patients we performed ETV twice. In 4 cases we used neuronavigation. In 6 cases ETV was performed in conjunction with endoscopic biopsy of the tumor. In 6 cases we had to repeat the procedure (4) or implant a ventriculo-peritoneal shunt (2) due to recurrence of symptoms. Results In our series we had 3 important complications: one thalamic injury and 2 intraventricular hemorrhages. In 4 cases we observed postoperative hyperthermia with the presence of meningeal symptoms. Two cerebrospinal fluid (CSF) leaks were secured with additional stitches and 2 CSF infections were treated with antibiotics. In 1 patient epileptic seizers were observed. Three others complained of nausea and vomiting. The initial success rate of ETV is 70%. Conclusions Based on our material we conclude that ETV is a useful and helpful procedure in non-communicating HCP. It carries 4% perioperative risk of serious complications which can be reduced by proper selection of patients, detailed plan and skilful performance of surgery in experienced hands and meticulous postoperative care.
Antineoplastic Effects of N-3 Polyunsaturated Fatty Acids in Combination With Drugs and Radiotherapy: Preventive and Therapeutic Strategies

Many data support the beneficial effect of n-3 polyunsaturated fatty acids (PUFAs) as chemopreventive and chemotherapeutic agents in the treatment of several chronic pathologies including cancer. Different molecular mechanisms have been proposed to explain their effects, including alterations in arachidonic acid oxidative metabolism and metabolic conversion of n-3 PUFAs to novel discovered bioactive derivatives; modification of oxidative stress; changes in cell membrane fluidity and structure and altered metabolism and function of membrane proteins. Considerable knowledge has been recently gathered on the possible beneficial effects of n-3 PUFAs administered in combination with different antineoplastic drugs and radiotherapy against melanoma, leukemia, neuroblastoma, and colon, breast, prostate, and lung cancer. The efficacy of these combinations has been demonstrated both in vivo and in vitro, and clinical trials have also been conducted. The aim of this review is to analyze all the n-3 PUFA combinations investigated so far, their efficacy, and the possible molecular mechanisms involved. It would be highly auspicable that the detailed analysis of the literature in this field could further support the common use of n-3 PUFAs in combination with other chemopreventive agents and warrant more clinical investigations designed to test the effectiveness of n-3 PUFA treatments coupled with conventional antineoplastic therapies.
Speculative analysis: exploring future development states of software

Most software tools and environments help developers analyze the present and past development states of their software systems. Few approaches have investigated the potential consequences of future actions the developers may perform. The commoditization of hardware, multi-core architectures, and cloud computing provide new potential for delivering apparently-instantaneous feedback to developers, informing them of the effects of changes that they may be considering to the software. For example, modern IDEs often provide "quick fix" suggestions for resolving compilation errors. Developers must scan this list and select the option they think will resolve the problem. Instead, we propose that the IDE should speculatively perform each of the suggestions in the background and provide information that helps developers select the best option for the given context. We believe the feedback enabled by speculative operations can improve developer productivity and software quality.
An Exploration of OpenCL on Multiple Hardware Platforms for a Numerical Relativity Application

Currently there is considerable interest in making use of many-core processor architectures, such as Nvidia and AMD graphics processing units (GPUs) for scientific computing. In this work we explore the use of the Open Computing Language (OpenCL) for a typical Numerical Relativity application: a time-domain Teukolsky equation solver (a linear, hyperbolic, partial differential equation solver using finite-differencing). OpenCL is the only vendor-agnostic and multi-platform parallel computing framework that has been adopted by all major processor vendors. Therefore, it allows us to write portable source-code and run it on a wide variety of compute hardware and perform meaningful comparisons. The outcome of our experimentation suggests that it is relatively straightforward to obtain order-of-magnitude gains in overall application performance by making use of many-core GPUs over multi-core CPUs and this fact is largely independent of the specific hardware architecture and vendor. We also observe that a single high-end GPU can match the performance of a small-sized, message-passing based CPU cluster.
Redundancy rates for renewal and other processes

The paper addresses the theoretical issue of universal noiseless source coding, viz., the best possible redundancy bound achievable for a given class of source models by block to variable-length lossless coding. For parametric model classes such as memoryless or Markov sources, this bound grows as the log of the block-length n, [1,2,4]. The authors show that for the non-parametric class of renewal processes the growth rate is O(square root n), while for the class of Markov renewal processes of order k the rate is O(n/sup k+1/k+2/). <<ETX>>
&#949;-Optimal Anomaly Detection in Parametric Tomography

The paper concerns the radiographic non-destructive testing of well-manufactured objects. The detection of anomalies is addressed from the statistical point of view as a binary hypothesis testing problem with nonlinear nuisance parameters. A new detection scheme is proposed as an alternative to the classical GLR test. It is shown that this original decision rule detects anomalies with a loss of a negligible (epsiv) part of optimality with respect to an optimal invariant test designed for the "closest" hypothesis testing problem with linear nuisance parameters
Modified Pulse Shapes for Effective Neural Stimulation

The electrical stimulation of neuronal structures is used as a treatment for many neurological disorders, e.g., for the treatment of Parkinson’s disease via deep brain stimulation (DBS). To reduce side effects, to avoid tissue or electrode damage, and to increase battery lifetimes, an effective but gentle electrical stimulation is of prime importance. We studied different modified pulse shapes for application in DBS with respect to their efficiency to initiate neuronal activity. Numerical simulations of two mathematical neuron models were performed to investigate the effectiveness of different modified pulse shapes. According to our results, the pulse shapes considered showed a considerably increased efficiency in terms of both activation and entrainment of neural activity. We found that the introduction of a gap with a specific and optimized duration in a biphasic pulse and the reversal of the standard pulse phase order yielded stimulation protocols that could increase the efficiency and therefore reduce the energy consumption of stimulation. The improvements were achieved by simple modifications of existing stimulation techniques. The modification of the pulse shapes resulted in an improvement of up to 50% for both the activation of resting neurons and the entrainment of bursting neurons.
Random time-frequency subdictionary design for sparse representations with greedy algorithms

Sparse signal approximation can be used to design efficient low bit-rate coding schemes. It heavily relies on the ability to design appropriate dictionaries and corresponding decomposition algorithms. The size of the dictionary, and therefore its resolution, is a key parameter that handles the tradeoff between sparsity and tractability. This work proposes the use of a non adaptive random sequence of subdictionaries in a greedy decomposition process, thus browsing a larger dictionary space in a probabilistic fashion with no additional projection cost nor parameter estimation. This technique leads to very sparse decompositions, at a controlled computational complexity. Experimental evaluation is provided as proof of concept for low bit rate compression of audio signals.
Frontoparietal structural network disconnections correlate with outcome after a severe stroke

Structural disconnectome analyses have provided valuable insights into how a stroke lesion results in widespread network disturbances and how these relate to deficits, recovery patterns, and outcome. Previous analyses have primarily focused on patients with relatively mild to moderate deficits. However, outcomes vary among survivors of severe strokes, and the mechanisms of recovery remain poorly understood. This study assesses the association between lesion-induced network disconnection and outcome after severe stroke. Thirty-eight ischaemic stroke patients underwent MRI brain imaging early after stroke and longitudinal clinical follow-up. Lesion information was integrated with normative connectome data to infer individual disconnectome profiles on a localized regional and region-to-region pathway level. Ordinal logistic regressions were computed to link disconnectome information to the modified Rankin Scale after 3-6 months. Disconnections of ipsilesional frontal, parietal and temporal cortical brain areas were significantly associated with a worse motor outcome after a severe stroke, adjusted for the initial deficit, lesion volume, and age. The analysis of the underlying pathways mediating this association revealed location specific results: For frontal, prefrontal and temporal brain areas, the association was primarily driven by relatively sparse intrahemispheric disconnections. In contrast, the ipsilesional primary motor cortex, the dorsal premotor cortex, and various parietal brain regions showed a remarkable involvement of either frontoparietal intrahemispheric or additionally interhemispheric disconnections. These results indicate that localized disconnection of multiple regions embedded in the structural frontoparietal network correlates with worse outcome after severe stroke. Specifically, primary motor and parietal cortices might gain a particular importance as they structurally link frontoparietal networks of both hemispheres. These data shed novel light on the significance of distinct brain networks for recovery after severe stroke.
Exploring Individual, Social, and Environmental Factors Related to Physical Activity: A Network Analysis

Objectives: Insufficient physical activity (PA) has long been a global health issue, and a number of studies have explored correlates of PA to identify the mechanisms underlying inactive lifestyles. In the literature, dozens of correlates have been identified at different (e.g., individual, environmental) levels, but there is little or no direct evidence for the mutual associations of these correlates. This study analysed 44 variables identified as theoretically and empirically relevant for PA to clarify the factors directly and indirectly associated with PA. Methods: A cross-sectional survey dataset of 19,005 Japanese-speaking adults (mean age = 53.50 years, SD = 17.40; 9,706 women) was analysed. The data encompassed demographic and anthropometric variables; self-reported PA levels; perceived social support and environments (e.g., awareness of urban facilities for PA); psychological traits and health-behaviour characteristics (e.g., personality, motivation, self-efficacy, decisional balance, process of change strategies); and technology use (e.g., mobile health apps). Results: Network analyses were performed to select meaningful associations (partial correlations) among variables, which identified nine variables directly positively associated with PA: job/employment status, self-efficacy, perceived social support, intrinsic motivation, stage of change, counter conditioning, self-reevaluation, environment, and technology use. Indirect associations (two-step neighbourhood) were identified for 40 (out of 44) variables, implying that most of the knwon PA-correlates are associated with PA--at least indirectly. Conclusion: Direct association with PA was identified for variables specified at different (individual-environmental) levels. The estimated mediation relationships echo the significance of the multilevel perspective in understanding how people maintain (in)active lifestyles.
COMPARING EFFICACY AND SAFETY OF LEFT ATRIAL APPENDAGE CLOSURE DEVICES: A NETWORK META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS

Introduction: Atrial fibrillation-related stroke is a leading cause of morbidity and mortality. Options for prevention include left atrial appendage closure devices or oral anticoagulation. However, it remains unclear which option may be superior overall. Methods: We conducted a systematic review and network meta-analysis of all clinical trials comparing the WATCHMAN, Amplatzer Amulet (Amulet), and/or OACs. The primary outcomes of interest were any stroke and all-cause death. Safety outcomes included any thromboembolism, device embolization, and pericardial effusion. We calculated risk ratios and heterogeneity statistics for eacjowh comparison, and calculated the probability of intervention superiority where at least one comparison was significant. Results: There were 441 articles identified from the search, from which 5 eligible RCTs were identified (n=1,811). Compared to OACs (all warfarin), risk of stroke was non-significantly decreased with WATCHMAN (RR=0.90, 95% CI: 0.48, 1.72, I2=13.4%), but risk with Amulet was non-significantly lower than WATCHMAN (RR=0.95, 95% CI: 0.50, 1.81). However, observed risk of all-cause death was significantly lower with Amulet than OAC (RR=0.53, 95% CI: 0.33, 0.85, I2=0%) and trended towards significance versus WATCHMAN (RR=0.74, 95% CI: 0.55, 1.02, p=0.06). The P-score was 0.982, signifying a >98% probability Amulet was superior to all alternatives. Risk of thromboembolism was non-significantly increased with WATCHMAN (RR=2.04, 95% CI: 0.23, 18.4) and Amulet (RR=1.54, 95% CI: 0.11, 22.1), with head-to-head comparison favoring Amulet (RR=0.76, 95% CI: 0.17, 3.38, I2=0%). Versus WATCHMAN, device embolization risk was non-significantly elevated with Amulet (RR= 2.38, 95% CI: 0.67, 8.43, I2=0%). Finally, risk of pericardial effusion was significantly elevated with Amulet versus OACs (RR=27.0, 95% CI: 3.48, 210) and versus WATCHMAN (RR=2.11, 95% CI: 1.41, 3.17, I2=0%). The inverse P-score for Amulet (0.9995) indicated a very high probability Amulet was inferior to alternatives. Conclusion: While risk of some adverse events was greater with Amulet, we estimated >98% probability Amulet is superior to alternatives in risk of death. Pooled patient-level analyses are warranted.
Chromosome testing in children with developmental delay in whom the aetiology is not evident clinically

A review was carried out to establish the value of chromosome testing in children with significant developmental delay, where the aetiology was not evident clinically. During 1990, 315 children had been assessed at a child development clinic and found to be significantly delayed in one or more areas of development; in 256, the aetiology was not evident clinically. Chromosome testing of these children revealed an abnormality in 10 (3.9%). Thirty children had dysmorphic features; six (20%) of these had an abnormal karyotype. Four (2%) of the 226 who had no dysmorphic features had a chromosome abnormality. One hundred and fifty‐five children had intellectual disability; eight (5%) of these had an abnormal karyotype. Two (2%) of 101 who had a specific delay in their development had a chromosome abnormality. The advantages of chromosome testing in children with developmental delay in whom the aetiology is not evident clinically are discussed.
Hormones of the hypothalamo-pituitary-gonadal axis in drug discrimination learning.

More than 30 years ago, T-maze studies with progesterone indicated that sex hormones have the potential to act as a discriminative stimulus in rats. Despite these early positive findings, the interest in discriminative stimulus properties of sex hormones remained low; few studies were dedicated to the investigation of discriminative stimulus properties of hypothalamo-pituitary-gonadal axis hormones (i.e., LHRH, LH/FSH, sex steroids). Nevertheless, the few studies that were published showed some interesting, and often sex-dependent results. Applying various methodologies (T-, or Y-maze, two-lever drug discrimination, taste aversion procedures), it was found that not only progesterone but also the two other principal sex steroids estradiol and testosterone can serve as discriminative stimuli in rodents. In addition to these gonadal hormones, the hypothalamic peptide LHRH (having a key role in the neuroendocrine regulation of steroid release from the gonads) appears to generate discriminative stimulus properties. Interestingly, recent (but preliminary) studies in postmenopausal women suggest that estradiol (and possibly progesterone) may also function as a discriminative stimulus in human subjects.
Growth of Non-c-Axis BSCCO Superconductor-Insulator Heterostructures

We attempted to grow non-c axis heterostructures of substrate-IS type with S = BSCCO and I = (Sr,Ca)CuO2. A careful selection of the films-substrate relationship is revealed as a key condition toward growth of layered heterostructures with different orientations. However this powerful principle, that is also a mandatory condition, is not sufficient in order to obtain high quality structures. The reasons are discussed looking for further solutions. Our comparative analysis is expanded to other heterostructures we reported in other works trying to reveal some of the more general problems of the non c-axis heterostructures growth.
Synergistic Activation of Vascular TRPC6 Channel by Receptor and Mechanical Stimulation via Phospholipase C/Diacylglycerol and Phospholipase A2/&ohgr;-Hydroxylase/ 20-HETE Pathways

TRPC6 is a non-voltage-gated Ca2+ entry/depolarization channel associated with vascular tone regulation and remodeling. Expressed TRPC6 channel responds to both neurohormonal and mechanical stimuli, the mechanism for which remains controversial. In this study, we examined the possible interactions of receptor and mechanical stimulations in activating this channel using the patch clamp technique. In HEK293 cells expressing TRPC6, application of mechanical stimuli (hypotonicity, shear, 2,4,6-trinitrophenol) caused, albeit not effective by themselves, a prominent potentiation of cationic currents (ITRPC6) induced by a muscarinic receptor agonist carbachol. This effect was insensitive to a tarantula toxin GsMTx-4 (5 &mgr;mol/L). A similar extent of mechanical potentiation was observed after activation of ITRPC6 by GTP&ggr;S or a diacylglycerol analog 1-oleoyl-2-acetyl-sn-glycerol (OAG). Single TRPC6 channel activity evoked by carbachol was also enhanced by a negative pressure added in the patch pipette. Mechanical potentiation of carbachol- or OAG-induced ITRPC6 was abolished by small interfering RNA knockdown of cytosolic phospholipase A2 or pharmacological inhibition of &ohgr;-hydroxylation of arachidonic acid into 20-HETE (20-hydroxyeicosatetraenoic acid). Conversely, direct application of 20-HETE enhanced both OAG-induced macroscopic and single channel TRPC6 currents. Essentially the same results were obtained for TRPC6-like cation channel in A7r5 myocytes, where its activation by noradrenaline or Arg8 vasopressin was greatly enhanced by mechanical stimuli via 20-HETE production. Furthermore, myogenic response of pressurized mesenteric artery was significantly enhanced by weak receptor stimulation dependently on 20-HETE production. These results collectively suggest that simultaneous operation of receptor and mechanical stimulations may synergistically amplify transmembrane Ca2+ mobilization through TRPC6 activation, thereby enhancing the vascular tone via phospholipase C/diacylglycerol and phospholipase A2/&ohgr;-hydroxylase/20-HETE pathways.
Toward a better understanding of rule initialisation and deletion

A number of heuristics have been used in Learning Classifier Systems to initialise parameters of new rules, to adjust fitness of parent rules when they generate offspring, and to select rules for deletion. Some have not been studied in the literature before. We study the interaction of these heuristics in an attempt to improve performance and detect any unnecessary methods. We evaluate the two published methods for initialisation of new rules in XCS and find the one based on parental values results in better evolutionary search but larger population sizes than the one based on population means. In preliminary work we demonstrate that when the difficulty of the 6 multiplexer is increased by reducing the population size limit and turning off subsumption we can improve performance by discounting the fitness of both parents and children.