Miracle-dz/UniFAR-FTUs huggingface dataset:
Ricci Flow and the Determinant of the Laplacian on Non-Compact Surfaces

On compact surfaces with or without boundary, Osgood, Phillips and Sarnak proved that the maximum of the determinant of the Laplacian within a conformal class of metrics with fixed area occurs at a metric of constant curvature and, for negative Euler characteristic, exhibited a flow from a given metric to a constant curvature metric along which the determinant increases. The aim of this paper is to perform a similar analysis for the determinant of the Laplacian on a non-compact surface whose ends are asymptotic to hyperbolic funnels or cusps. In that context, we show that the Ricci flow converges to a metric of constant curvature and that the determinant increases along this flow.
Multi-objective optimization approach to detecting extremal patterns in social networks

This paper introduces the use of extremal patterns as a way to characterize social networks. The concepts of Pareto-dominance, multi-objective optimization, and estimation of distribution algorithms are integrated in a general strategy to compute the multiple extremal patterns. The algorithm is applied to the identification of sets of subjects that have the broadest direct network reachability in a social network extracted from the Reality mining dataset.
J an 2 00 6 Advanced Finite Element Method for Nano-Resonators

Miniaturized optical resonators with spatial dimensions of the order of the wavelength of the trapped light offer prospects for a variety of new applications like quantum processing or construction of meta-materials. Light propagation in these structures is modelled by Maxwell’s equations. For a deeper numerical analysis one may compute the scattered field when the structure is illuminated or one may compute the resonances of the structure. We therefore address in this paper the electromagnetic scattering problem as well as the computation of resonances in an open system. For the simulation efficient and reliable numerical methods are required which cope with the infinite domain. We use transparent boundary conditions based on the Perfectly Matched Layer Method (PML) combined with a novel adaptive strategy to determine optimal discretization parameters like the thickness of the sponge layer or the mesh width. Further a novel iterative solver for time-harmonic Maxwell’s equations is presented.
Percutaneous Sclerotherapy for Facial Venous Malformations: Subjective Clinical and Objective MR Imaging Follow-Up Results

BACKGROUND AND PURPOSE: Venous malformations are the most common of all vascular anomalies, 40% of which are found in the head and neck. We discuss results of percutaneous sclerotherapy using bleomycin for facial VMs by using subjective clinical assessment and objective changes on MR imaging. MATERIALS AND METHODS: Thirty-seven patients with facial VMs were treated by percutaneous sclerotherapy with bleomycin. Of these, 31 patients with 32 lesions had pre- and posttreatment MR imaging. Each lesion received between 1 and 9 sclerotherapy sessions (average, 3.5). MR findings and clinical results of treatment were retrospectively reviewed. Clinical results were based on the physician's physical examination and interview of the patient; these were classified as worse, unchanged, or better. Objective results on MR imaging were classified as worse, no change, minor improvement (<50% decrease in size), marked improvement (≥50% decrease), or cure. Objective and subjective results were compared. RESULTS: Twenty-one lesions showed objective improvement on MR imaging. Of these, 10 showed minor decrease in size and 11 showed marked decrease. Eleven lesions showed no change on MR imaging. No VMs were worse or completely cured. Subjectively, 29 patients and 30 clinicians thought that lesions improved. Four of 32 (12.5%) patients suffered minor transient complications. CONCLUSIONS: Percutaneous sclerotherapy by using bleomycin is a safe technique to objectively decrease size and subjectively alleviate symptoms of facial VMs. Subjective clinical improvement is not always associated with visual size reduction on MR imaging. Minimal size reduction or partial fibrosis of the lesion may be enough to achieve subjective clinical improvement.
How to Cooperate Locally to Improve Global Privacy in Social Networks? On Amplification of Privacy Preserving Data Aggregation

In many systems the privacy of users depends on the number of participants applying collectively some method to protect their security. Indeed, there are numerous already classic results about revealing aggregated data from a set of users. Apart from data aggregation, it has been noticed that in a wider context privacy can be often reduced to being hidden in a crowd. Generally, the problems is how to create such crowd. This task may be not easy in some distributed systems, wherein gatheringenough "individuals" is hard for practical reasons.Such examples are social networks (or similar systems), where users have only a limited number of semi trusted contacts and their aim is to reveal some aggregated data in a privacy preserving manner. This may be particularly problematic in the presence of a strong adversary that can additionally corrupt some users.We show two methods that allow to significantly amplify privacy with only limited number of local operations and very moderate communication overhead. Apart from theoretical analysis we show experimental results on topologies of real-life social networks to demonstrate that our methods can significantly amplify privacy of chosen aggregation protocols even facing a massive attack of a powerful adversary.We believe however that our results can have much wider applications for improving security of systems based on locally trusted relations.
A Framework for Delivering Personalized e-Government Tourism Services

E-government (e-Gov) has become one of the most important parts of government strategies. Significant efforts have been devoted to e-Gov tourism services in many countries because tourism is one of the major profitable industries. However, the current e-Gov tourism services are limited to simple online presentation of tourism information. Intelligent e-Gov tourism services, such as the personalized e-Gov (Pe-Gov) tourism services, are highly desirable for helping users decide ”where to go, and what to do/see” amongst massive number of destinations and enormous attractiveness and activities. This paper proposes a framework of PeGov tourism services using recommender system techniques and semantic ontology. This framework has the potential to enable tourism information seekers to locate the most interesting destinations with the most suitable activities with the least search efforts. Its workflow and some outstanding features are depicted with
Distance-Constrained Force-Directed Process Mapping for MPSoC Architectures

In this paper, we present a novel approach for automated mapping of software processes onto the cores of MPSoC architectures using a regular packet-based communication infrastructure. During the mapping determination, the communication distance as well as the routing algorithm for packet-based communication are taken into account. The basic idea of the developed approach is the reduction of communication conflicts on the communication network links for reducing the overall communication latency and hence for increasing the total system performance. The presented approach is based on the idea of force-directed scheduling (FDS) from high-level synthesis and uses forces for determining an optimized process mapping. The approach constrains the cores, that are used for the calculation of possible mappings, by the communication distance of the communicating processes. We present results obtained from an advanced driver assistance system on a Tilera TILEPro64 processor.
Why Do Demand Curves for Stocks Slope Down?

Abstract Representative agent models are inconsistent with existing empirical evidence for steep demand curves for individual stocks. This paper resolves the puzzle by proposing that stock prices are instead set by two separate classes of investors. While the market portfolio is still priced by individual investors based on their collective risk aversion, those individual investors also delegate part of their wealth to active money managers, who use that capital to price stocks in the cross section. In equilibrium, the fee charged by active managers has to equal the before-fee alpha they earn. This endogenously determines the amount of active capital and the slopes of demand curves. A calibration of the model reveals that demand curves can be steep enough to match the magnitude of many empirical findings, including the price effects for stocks entering or leaving the S&P 500 index.
Bioinformatics Original Paper a New Summarization Method for Affymetrix Probe Level Data

Motivation: We propose a new model-based technique for summarizing high-density oligonucleotide array data at probe level for Affymetrix GeneChips. The new summarization method is based on a factor analysis model for which a Bayesian maximum a posteriori method optimizes the model parameters under the assumption of Gaussian measurement noise. Thereafter, the RNA concentration is estimated from the model. In contrast to previous methods our new method called 'Factor Analysis for Robust Microarray Summarization (FARMS)' supplies both P-values indicating interesting information and signal intensity values. Results: We compare FARMS on Affymetrix's spike-in and Gene Logic's dilution data to established algorithms like Affymetrix Microarray Suite (MAS) 5.0, Model Based Expression Index (MBEI), Robust Multi-array Average (RMA). Further, we compared FARMS with 43 other methods via the 'Affycomp II' competition. The experimental results show that FARMS with default parameters outperforms previous methods if both sensitivity and specificity are simultaneously considered by the area under the receiver operating curve (AUC). We measured two quantities through the AUC: correctly detected expression changes versus wrongly detected (fold change) and correctly detected significantly different expressed genes in two sets of arrays versus wrongly detected (P-value). Furthermore FARMS is computationally less expensive then RMA, MAS and MBEI.
Natural Memory Beyond the Storage Model: Repression, Trauma, and the Construction of a Personal Past

Naturally occurring memory processes show features which are difficult to investigate by conventional cognitive neuroscience paradigms. Distortions of memory for problematic contents are described both by psychoanalysis (internal conflicts) and research on post-traumatic stress disorder (PTSD; external traumata). Typically, declarative memory for these contents is impaired – possibly due to repression in the case of internal conflicts or due to dissociation in the case of external traumata – but they continue to exert an unconscious pathological influence: neurotic symptoms or psychosomatic disorders after repression or flashbacks and intrusions in PTSD after dissociation. Several experimental paradigms aim at investigating repression in healthy control subjects. We argue that these paradigms do not adequately operationalize the clinical process of repression, because they rely on an intentional inhibition of random stimuli (suppression). Furthermore, these paradigms ignore that memory distortions due to repression or dissociation are most accurately characterized by a lack of self-referential processing, resulting in an impaired integration of these contents into the self. This aspect of repression and dissociation cannot be captured by the concept of memory as a storage device which is usually employed in the cognitive neurosciences. It can only be assessed within the framework of a constructivist memory concept, according to which successful memory involves a reconstruction of experiences such that they fit into a representation of the self. We suggest several experimental paradigms that allow for the investigation of the neural correlates of repressed memories and trauma-induced memory distortions based on a constructivist memory concept.
Posing Multibody Dynamics With Friction and Contact as a Differential Complementarity Problem

We use a complementarity approach to pose the Coulomb friction model, combine it with a non-penetration condition, and append to a differential algebraic problem to characterize the dynamics of multibody systems with friction and contact. The resulting problem is relaxed to a Cone Complementarity Problem, whose solution is shown to represent the first order optimality condition of a quadratic program with conic constraints.
Polyribosomes are increased in spines of CA1 dendrites 2 h after the induction of LTP in mature rat hippocampal slices

Enduring long‐term potentiation (LTP) requires immediate protein synthesis, hence we assessed whether more polyribosomes are present in dendritic spines of mature hippocampal dendrites after the induction of LTP. Reconstructions from serial section transmission electron microscopy (sSTEM) revealed more dendritic polyribosomes 2 h posttetanus, relative to low‐frequency stimulation (LFS). Polyribosomes were present in spines of all shapes with larger postsynaptic densities after 2 h, suggesting a coordinated local protein synthesis among many synapses to replenish proteins utilized during an earlier phase of LTP. © 2006 Wiley‐Liss, Inc.
Fast Arithmetic for Public-Key Algorithms in Galois Fields with Composite Exponents

The article describes a novel class of arithmetic architectures for Galois fields GF(2/sup k/). The main applications of the architecture are public key systems which are based on the discrete logarithm problem for elliptic curves. The architectures use a representation of the field GF(2/sup k/) as GF((2/sup n/)/sup m/), where k=n/spl middot/m. The approach explores bit parallel arithmetic in the subfield GF(2/sup n/) and serial processing for the extension field arithmetic. This mixed parallel-serial (hybrid) approach can lead to fast implementations. As the core module, a hybrid multiplier is introduced and several optimizations are discussed. We provide two different approaches to squaring. We develop exact expressions for the complexity of parallel squarers in composite fields, which can have a surprisingly low complexity. The hybrid architectures are capable of exploring the time-space trade-off paradigm in a flexible manner. In particular, the number of clock cycles for one field multiplication, which is the atomic operation in most public key schemes, can be reduced by a factor of n compared to other known realizations. The acceleration is achieved at the cost of an increased computational complexity. We describe a proof-of-concept implementation of an ASIC for multiplication and squaring in GF((2/sup n/)/sup m/), m variable.
Precedes : A Semantic Relation in FrameNet

Automatic language processing systems depend on, among others factors, the effectiveness in modeling human cognitive abilities, including the capacity to draw inferences about prototypical or expected sequences of events and their temporal order. Appropriate response to a crisis is as important for public security as are efforts to prevent any such natural or man made disaster. Recent research (Mehrota et al. 2008) has recognized the need for accurate and actionable situation awareness during emergencies, where timely status updates are critical for effective crisis management. The present paper constitutes a contribution to situation awareness for Natural Language Processing (NLP) applications to improve communication among first responders, and features the frame-to-frame semantic relation Precedes, as implemented in FrameNet (http://framenet.icsi.berkeley.edu). Specifically, this work demonstrates the necessity and importance of the information encoded with Precedes for NLP applications, advocating the inclusion of such information in systems for security applications.
Sensorized environment for self-communication based on observation of daily human behavior

This paper describes an intelligent environmental system, SELF (Sensorized Environment for Life), that enables a person to maintain his or her health through "self-communication. " The system externalizes a "self" by storing personal data such as physiological status, analyzing it, and reporting useful information to assist the person, in maintaining his or her health. To establish the methodology to create such a system, this study analyzes and re-defines the self as an object of information processing. Self-communication is nothing but understanding ourselves objectively. It is not easy to put into practice because it requires a visualized or numerized representation of oneself. As an example of an externalized self, this study focused on the physiological status of a person. The physiological status is obtained as follows: SELF observes the person's behavior with distributed sensors invisibly embedded in the daily environment, extracts physiological parameters from it, analyzes the parameters, and accumulates the results. The accumulated results are used for reporting useful information to maintain the person's health. The authors constructed a model room for SELF consisting of a bed with pressure sensor array, a ceiling lighting dome with a microphone, and a washstand with a display. Fundamental results of self-externalization using SELF are presented.
QMUL-PH-07-02 Recursion Relations for One-Loop Gravity Amplitudes

We study the application of recursion relations to the calculation of finite one-loop gravity amplitudes. It is shown explicitly that the known five, and six graviton one-loop amplitudes for which the external legs have identical outgoing helicities, and the four graviton amplitude with helicities −+++ can be derived from simple recursion relations. The latter amplitude is derived by introducing a one-loop three-point vertex of gravitons of positive helicity, which is the counterpart in gravity of the one-loop three-plus vertex in Yang-Mills. We show that new issues arise for the five point amplitude with helicities − + + + +, where the application of known methods does not appear to work, and we discuss possible resolutions. {a.brandhuber, s.mcnamara, w.j.spence, g.travaglini}@qmul.ac. uk
A model for the migration to object-oriented software development with special emphasis on improvement of acceptance

Object oriented technology has been established as an important new paradigm in software development. Thus, many organizations involved in any kind of software production plan to migrate to object oriented technology or have already started this process. Besides several successful migrations, many failures occur. In order to reduce the risk of failure during the migration process, we developed a migration model based on an empirical study. The application of this model leads to a better understanding of the migration process and supports its planning, designing and implementation, putting special emphasis on improvement of acceptance. The theoretical foundations of our migration model come from technology management, organizational research (i.e. change management, and organizational roles), as well as existing approaches and models for this kind of migration. Our migration model consists of three main parts: the migration process model, the definition of organizational roles, and the use of acceptance strategies such as information and communication, participation, and further education. The main results concerning the rise of acceptance strategies, based on the results of the empirical study, are presented.
Temporal Envelopes in Sine-Wave Speech Recognition

There is a long debate on the relative importance of spectral and temporal cues in speech perception theories. On the one hand, the highly-intelligible sine-wave speech (SWS) has been viewed as a representation of the global spectral structure of the speech signal. On the other hand, there is accumulating evidence showing that the temporal aspects of speech without spectral details provide sufficient speech understanding. The present study explored whether the temporal envelopes imbedded in the SWS contribute to its intelligibility. In the experiments, both SWS and natural speech signals were processed with noise and tone vocoders to remove the spectral details but to preserve the temporal envelopes. Twenty-two normal-hearing, native English-speaking adult listeners participated in sentence recognition tasks. Speech recognition performance of vocoder-processed SWS was slightly inferior to that of vocoder-processed natural speech but both reached plateau performance at 6-8 channels. Acoustic analysis further indicated that the temporal envelopes of the SWS were almost identical to those of the natural speech, with a mean correlation coefficient r = 0.949 across all sentences. The results provide strong evidence that the SWS represents both spectral and temporal structures of the speech and that the temporal envelopes imbedded in SWS carry important information for speech recognition.
Finding a partner in the ocean: molecular and evolutionary bases of the response to sexual cues in a planktonic diatom

Summary Microalgae play a major role as primary producers in aquatic ecosystems. Cell signalling regulates their interactions with the environment and other organisms, yet this process in phytoplankton is poorly defined. Using the marine planktonic diatom Pseudo‐nitzschia multistriata, we investigated the cell response to cues released during sexual reproduction, an event that demands strong regulatory mechanisms and impacts on population dynamics. We sequenced the genome of P. multistriata and performed phylogenomic and transcriptomic analyses, which allowed the definition of gene gains and losses, horizontal gene transfers, conservation and evolutionary rate of sex‐related genes. We also identified a small number of conserved noncoding elements. Sexual reproduction impacted on cell cycle progression and induced an asymmetric response of the opposite mating types. G protein‐coupled receptors and cyclic guanosine monophosphate (cGMP) are implicated in the response to sexual cues, which overall entails a modulation of cell cycle, meiosis‐related and nutrient transporter genes, suggesting a fine control of nutrient uptake even under nutrient‐replete conditions. The controllable life cycle and the genome sequence of P. multistriata allow the reconstruction of changes occurring in diatoms in a key phase of their life cycle, providing hints on the evolution and putative function of their genes and empowering studies on sexual reproduction.
Activation of NMDA receptors promotes dendritic spine development through MMP-mediated ICAM-5 cleavage

Matrix metalloproteinase (MMP)-2 and -9 are pivotal in remodeling many tissues. However, their functions and candidate substrates for brain development are poorly characterized. Intercellular adhesion molecule-5 (ICAM-5; Telencephalin) is a neuronal adhesion molecule that regulates dendritic elongation and spine maturation. We find that ICAM-5 is cleaved from hippocampal neurons when the cells are treated with N-methyl-d-aspartic acid (NMDA) or α-amino-3-hydroxy-5-methylisoxazole-propionic acid (AMPA). The cleavage is blocked by MMP-2 and -9 inhibitors and small interfering RNAs. Newborn MMP-2– and MMP-9–deficient mice brains contain more full-length ICAM-5 than wild-type mice. NMDA receptor activation disrupts the actin cytoskeletal association of ICAM-5, which promotes its cleavage. ICAM-5 is mainly located in dendritic filopodia and immature thin spines. MMP inhibitors block the NMDA-induced cleavage of ICAM-5 more efficiently in dendritic shafts than in thin spines. ICAM-5 deficiency causes retraction of thin spine heads in response to NMDA stimulation. Soluble ICAM-5 promotes elongation of dendritic filopodia from wild-type neurons, but not from ICAM-5–deficient neurons. Thus, MMPs are important for ICAM-5–mediated dendritic spine development.