Abstract:
This paper describes a probabilistic top-down parser for minimalist grammars. Top-down parsers have the great advantage of having a certain predictive power during the parsing, which takes place in a left-to-right reading of the sentence. Such parsers have already been well-implemented and studied in the case of Context-Free Grammars, which are already top-down, but these are difficult to adapt to Minimalist Grammars, which generate sentences bottom-up. I propose here a way of rewriting Minimalist Grammars as Linear Context-Free Rewriting Systems, allowing to easily create a top-down parser. This rewriting allows also to put a probabilistic field on these grammars, which can be used to accelerate the parser. Finally, I propose a method of refining the probabilistic field by using algorithms used in data compression.

Abstract:
We propose a new statistical model for computational linguistics. Rather than trying to estimate directly the probability distribution of a random sentence of the language, we define a Markov chain on finite sets of sentences with many finite recurrent communicating classes and define our language model as the invariant probability measures of the chain on each recurrent communicating class. This Markov chain, that we call a communication model, recombines at each step randomly the set of sentences forming its current state, using some grammar rules. When the grammar rules are fixed and known in advance instead of being estimated on the fly, we can prove supplementary mathematical properties. In particular, we can prove in this case that all states are recurrent states, so that the chain defines a partition of its state space into finite recurrent communicating classes. We show that our approach is a decisive departure from Markov models at the sentence level and discuss its relationships with Context Free Grammars. Although the toric grammars we use are closely related to Context Free Grammars, the way we generate the language from the grammar is qualitatively different. Our communication model has two purposes. On the one hand, it is used to define indirectly the probability distribution of a random sentence of the language. On the other hand it can serve as a (crude) model of language transmission from one speaker to another speaker through the communication of a (large) set of sentences.

Abstract:
A multicentre, observational open trial enrolled patients with primary FM (44.1 ± 8.1 y), and matched controls (44.1 ± 7.3 y). Outcome measurements and gait analyses were available for 52 pairs. A 3-step statistical analysis was carried out. A preliminary single blind analysis using k-means cluster was performed as an initial validation of gait markers. Then in order to quantify FM patients according to psychometric and gait variables an open descriptive analysis comparing patients and controls were made, and correlations between gait variables and main outcomes were calculated. Finally using cluster analysis, we described subgroups for each gait variable and looked for significant differences in self-reported assessments.SF was the most discriminating gait variable (73% of patients and controls). SF, SR, and CCP were different between patients and controls. There was a non-significant association between SF, FIQ and physical components from Short-Form 36 (p = 0.06). SR was correlated to FIQ (p = 0.01) and catastrophizing (p = 0.05) while CCP was correlated to pain (p = 0.01). The SF cluster identified 3 subgroups with a particular one characterized by normal SF, low pain, high activity and hyperkinesia. The SR cluster identified 2 distinct subgroups: the one with a reduced SR was distinguished by high FIQ, poor coping and altered affective status.Gait analysis may provide additional information in the identification of subgroups among fibromyalgia patients. Gait analysis provided relevant information about physical and cognitive status, and pain behavior. Further studies are needed to better understand gait analysis implications in FM.In clinical trials and observational research studies, fibromyalgia (FM) is usually diagnosed according to American College of Rheumatology (ACR) 1990 criteria [1]. However, patients fulfilling the ACR classification criteria for FM do not constitute a homogeneous group and the classification of FM into different subgroups calls for b

Abstract:
We performed functional magnetic resonance imaging (fMRI) in 42 subjects; 14 healthy and 28 age-matched FM patients (2 patients per HC), during randomly presented, subjectively calibrated pressure pain stimuli. A seed-based functional connectivity analysis of brain activity was performed. The seed coordinates were based on the findings from our previous study, comparing the fMRI signal during calibrated pressure pain in FM and HC: the rostral anterior cingulate cortex (rACC) and thalamus.FM patients required significantly less pressure (kPa) to reach calibrated pain at 50？mm on a 0–100 visual analogue scale (p？<？.001, two-tailed). During fMRI scanning, the rACC displayed significantly higher connectivity to the amygdala, hippocampus, and brainstem in healthy controls, compared to FM patients. There were no regions where FM patients showed higher rACC connectivity. Thalamus showed significantly higher connectivity to the orbitofrontal cortex in healthy controls but no regions showed higher thalamic connectivity in FM patients.Patients with FM displayed less connectivity within the brain’s pain inhibitory network during calibrated pressure pain, compared to healthy controls. The present study provides brain-imaging evidence on how brain regions involved in homeostatic control of pain are less connected in FM patients. It is possible that the dysfunction of the descending pain modulatory network plays an important role in maintenance of FM pain and our results may translate into clinical implications by using the functional connectivity of the pain modulatory network as an objective measure of pain dysregulation.

Abstract:
Sorption isotherms of methane and hydrogen on Cu_{3}(BTC)_{2} have been measured in the temperature range from 273 to 318 K and at pressures up to 15 MPa. H_{2} excess sorption capacities of the Cu_{3}(BTC)_{2} amounted to 3.9 mg/g at 14 MPa. Promising maximum CH_{4} excess sorption capacities on the same sample were reached at approximately 5 MPa. They amounted to 101, 100, 92 and 80 mg/g at 273, 278, 293 and 318 K, respectively. The sorbed phase density was essestially the same for all temperatures and amounted to ~600 kg/m^{3}. Structural changes of the Cu_{3}(BTC)_{2} samples after thermal activation and treatment with high pressure H_{2} and CH_{4} were tested. It was found that the initial micropore structure has virtually disappeared as evidenced by a decrease of the Langmuir specific surface area by a factor ~3 and CO_{2} micropore volume by a factor of ~4 for H_{2} and ~3 for CH_{4}. This is in line with an increase in the average pore diameter from initially 9.2 to 15.7 for H_{2} and 12.8 for CH_{4}.

Abstract:
A
Minkowskian solution of the equation of General Relativity (as written by
Einstein in 1915) is trivial because it simply means that both members of the
equation are equal to zero. However, if alternatively, one considers the
complete equation with a non-zero constant Λ (Einstein
1917), a Minkowskian solution is no longer trivial because it amounts to impose
a constraint on the right hand side of the equation (i.e. a non-null
stress-energy tensor). If furthermore one identifies (as usual) this tensor to
the one of a perfect fluid, one finds that this fluid has a positive energy
density and a negative pressure that depend on the three constants of the
equation (i.e. gravitational constant G,
cosmological constant Λ and velocity of light c). When doing that (§1), one has
to consider the “Minkowskian Vacuum” as a physical object of GR (an enigmatic
non-baryonic Minkowskian fluid). Can one build a model of this object on the
basis of a dynamical equilibrium between the effective gravitational attraction
due to the positive energy density versus the negative pressure repulsion? We
propose to study such a model, where the (enigmatic) fluid is assumed to exist
only in a limited sphere whose surface acts like a “test body” sensitive to the
gravitational field created by the fluid. No static equilibrium exists, but a
pseudoNewtonian “dynamical equilibrium” (§2) can be reached if the
pseudoEuclidean fluid is in state of expansion. Up to there, we have simply
constructed a model of an “abstract Universe” (i.e.the limited sphere: There is no fluid outside this sphere!) that
gives to a (purely mathematical) constant Λ a concrete physical meaning. We
discover finally that our expanding fluid has not only dynamical
(gravitational) properties (§3) but also optical properties that are connected
with Doppler Redshift (§4). Remembering that recent observations in Cosmology
indicate that the “real Universe” seems to be “Flat” and in “Accelerated
Expansion”; remembering also (after all) that the archetypal Flat Universe is
simply a Minkowskian Universe, we logically wonder if the unexpected
Minkowskian global solution, could not be also a significant cosmological model
(conclusion).

Abstract:
Combination of multiple-input multiple-output (MIMO) with orthogonal frequency division multiplexing (OFDM) has become a promising candidate for high performance wireless communications. However one major disadvantage of MIMO-OFDM systems lies in a prohibitively large peak-to-average power ratio (PAPR) of the transmitted signal on each antenna. In this paper we extend from SISO to MIMO systems a method based on allocating dedicated subcarriers for PAPR mitigation. These subcarriers are located on unused subcarriers of OFDM spectrum under the assumption they all fall under the power mask. This is originally implemented with a SOCP optimization algorithm applied before space time coding scheme. This jointly mitigates PAPR on each MIMO branch scheme. This approach does not degrade the bit-error-rate (BER) and the data bit rate and no side information (SI) transmission is required. Simulation results are presented in the IEEE 802.16 WiMAX standard contexts: an Alamouti space time code with two transmitted antennas and 256 OFDM subcarriers are considered where 56 of which are unused and allocated for PAPR reduction. PAPR gains up to 7dB are obtained depending on mean power increase limitation. Moreover, with a spectrum mask constraint, this method is standard compliant.