456 research outputs found
Serial order of conditional stimuli as a discriminative cue for Pavlovian conditioning
The serial order in which events occur can be a signal for different outcomes and therefore might be a determinant of how an animal should respond. In this report, we propose a novel design for studying serial order learning in Pavlovian conditioning. In both Experiments 1a and 1b, hungry rats were trained with successively presented pairs of auditory and visual stimuli (e.g., A --> B) using four different stimuli (A-D). Four orders were paired with food (A --> B, B --> C, C --> D, D --> A) while the reversals were extinguished (B --> A, C --> B, D --> C, A --> D). An analysis of responding from the second element of each pair showed that the rats discriminated trial types that preceded food from those that did not. A replication of the effect using a completely counterbalanced design is described in Experiment 1b. These results suggest that rats can use the serial or temporal order of two sequentially presented non-overlapping elements as the basis for discrimination. Two associative accounts are suggested as possible mechanisms for solving the discrimination
Assessing the use and effectiveness of e-health and assistive technologies for disabled people: The multidimensional TEMSED model
Computing the endomorphism ring of an ordinary elliptic curve over a finite field
We present two algorithms to compute the endomorphism ring of an ordinary
elliptic curve E defined over a finite field F_q. Under suitable heuristic
assumptions, both have subexponential complexity. We bound the complexity of
the first algorithm in terms of log q, while our bound for the second algorithm
depends primarily on log |D_E|, where D_E is the discriminant of the order
isomorphic to End(E). As a byproduct, our method yields a short certificate
that may be used to verify that the endomorphism ring is as claimed.Comment: 16 pages (minor edits
Mapping Microstructural Dynamics up to the Nanosecond of the Conjugated Polymer P3HT in the Solid State
We present a detailed study of the structure-dynamics relationship of
regio-regular and regio-random PEHT using different neutron scattering
techniques. Deuteration is employed to modulate the coherent and incoherent
cross-sections, allowing particularly to access both self-motions and
collective dynamics of the materials. The measurements are underpinned by
extensive quantitative calculations using classical MD, as well as first
principles quantum chemistry. MD reproduced well the main structural features
and slow motions, and shed light on differences in collective dynamics between
Q-values linked with the stacking and the lamellar stacking, with the
crystalline phase being the most impacted. On the other hand MD led to a
limited description of molecular vibrations. In this context, first principles
molecular calculations described well the high-energy vibrational features (
900 cm ), while periodic calculations allowed to better describe the
low- and mid-energy vibrational ranges ( 200-900 cm ). The mid-energy
range is predominantly associated with both intra-molecular and inter-molecular
mode coupling, which encloses information about both the polymer conformation
and the polymer packing at short range. One of the outcomes of this study is
the validation of the common assumption made that RRa-P3HT is a good
approximation for the amorphous phase of RR-P3HT at the macroscopic level. The
present work helps to clarify unambiguously the latter point which has been
largely overlooked in the literature. We highlight the importance to complement
optical spectroscopy techniques with inelastic neutron scattering. The latter
offering the advantage of being insensitive to the delocalized -electron
system, and thus enabling to infer relevant quantities like conjugation
lengths, for instance, impacting properties of conjugated polymer.Comment: Featured as ACS Editors' Choice. Featured on the Cover of the
December 10, 2019 issue of Chemistry of Material
Observations of present-day activity at super-fast spreading : volcanic, hydrothermal and tectonic studies of the EPR 17-19°S
Formation of Flavanol-aldehyde Adducts in Barrel-aged White Wine – Possible Contribution of These Products to Colour
This paper describes the formation and diversity of new compounds resulting from the polymerisation of furanic andphenolic flavanol-aldehydes with HPLC‑DAD and LC‑ES/MS analysis. Polymerisation, resulting from nucleophilicreactions, formed dimers, trimers, soluble and insoluble polymers. Reactions in hydroalcoholic solution with purealdehydes (phenolic and furanic) and flavanols (catechin) were studied. The study was repeated with differentaldehydes in white wine. This research focused particularly on the colour properties of the released products and theirpotential impact on the colour of white wine. Some products were purified and isolated; these were mainly catechinfurfuraldehyde,catechin-methyl-5-furfuraldehyde, catechin-hydroxymethyl-furfuraldehyde,catechin-vanillin, andcatechin-syringaldehyde dimers. The most powerful coloured products resulted from furanic aldehydes. Over thecourse of the experiment, the reaction produced dimers, trimers and oligomers. After 50 to 60 days, the colour of thesolution was mainly due to soluble polymeric forms. In addition, the role of SO2, generally used during vinificationand ageing, was studied. The influence of SO2 on the kinetics of the reaction was limited
Infrared Spectroscopic Study of a Selection of AGB and Post-AGB Stars
We present here near-infrared spectroscopy in the H and K bands of a
selection of nearly 80 stars that belong to various AGB types, namely S type, M
type and SR type. This sample also includes 16 Post-AGB (PAGB) stars. From
these spectra, we seek correlations between the equivalent widths of some
important spectral signatures and the infrared colors that are indicative of
mass loss. Repeated spectroscopic observations were made on some PAGB stars to
look for spectral variations. We also analyse archival SPITZER mid-infrared
spectra on a few PAGB stars to identify spectral features due to PAH molecules
providing confirmation of the advanced stage of their evolution. Further, we
model the SEDs of the stars (compiled from archival data) and compare
circumstellar dust parameters and mass loss rates in different types.
Our near-infrared spectra show that in the case of M and S type stars, the
equivalent widths of the CO(3-0) band are moderately correlated with infrared
colors, suggesting a possible relationship with mass loss processes. A few PAGB
stars revealed short term variability in their spectra, indicating episodic
mass loss: the cooler stars showed in CO first overtone bands and the hotter
ones showed in HI Brackett lines. Our spectra on IRAS 19399+2312 suggest that
it is a transition object. From the SPITZER spectra, there seems to be a
dependence between the spectral type of the PAGB stars and the strength of the
PAH features. Modelling of SEDs showed among the M and PAGB stars that the
higher the mass loss rates, the higher the [K-12] colour in our sample.Comment: 14 pages; accepted in MNRAS, 200
Multidisciplinary intensive functional restoration versus outpatient active physiotherapy in chronic low back pain: a randomized controlled trial.
STUDY DESIGN: Randomized parallel group comparative trial with a 1-year follow-up period.
OBJECTIVE: To compare in a population of patients with chronic low back pain, the effectiveness of a functional restoration program (FRP), including intensive physical training and a multidisciplinary approach, with an outpatient active physiotherapy program at 1-year follow-up.
SUMMARY OF BACKGROUND DATA: Controlled studies conducted in the United States and in Northern Europe showed a benefit of FRPs, especially on return to work. Randomized studies have compared these programs with standard care. A previously reported study presented the effectiveness at 6 months of both functional restoration and active physiotherapy, with a significantly greater reduction of sick-leave days for functional restoration.
METHODS: A total of 132 patients with low back pain were randomized to either FRP (68 patients) or active individual therapy (64 patients). One patient did not complete the FRP; 19 patients were lost to follow-up (4 in the FRP group and 15 in the active individual treatment group). The number of sick-leave days in 2 years before the program was similar in both groups (180 ± 135.1 days in active individual treatment vs. 185 ± 149.8 days in FRP, P = 0.847).
RESULTS: In both groups, at 1-year follow-up, intensity of pain, flexibility, trunk muscle endurance, Dallas daily activities and work and leisure scores, and number of sick-leave days were significantly improved compared with baseline. The number of sick-leave days was significantly lower in the FRP group.
CONCLUSION: Both programs are efficient in reducing disability and sick-leave days. The FRP is significantly more effective in reducing sick-leave days. Further analysis is required to determine if this overweighs the difference in costs of both programs
PREMUS 2010 - 7e conférence scientifique internationale sur la prévention des troubles musculosquelettiques
Après Boston en 2007, le congrès PREMUS 2010 (Seventh International Scientific Conference on Prevention of Work-Related Musculoskeletal Disorders) s\u27est déroulé en France pour la première fois depuis sa création en 1992.
Il s\u27agit du principal congrès international sur les troubles musculosquelettiques (TMS) qui regroupe, tous les trois ans, sous l\u27égide de l\u27International Commission of Occupational Health (ICOH - CIST), les spécialistes internationaux du sujet (biomécaniciens, physiologistes, épidémiologistes, médecins du travail, ergonomes, préventeurs, cliniciens, psychologues, sociologues, spécialistes de gestion, etc.).
Plus de 650 chercheurs et préventeurs de 40 pays ont participé à ce congrès scientifique de haut niveau qui tient aussi lieu de forum international pour les acteurs de la prévention des TMS des membres et du rachis.
Après une présentation des principaux thèmes abordés au cours de la semaine, une sélection des sujets qui ont particulièrement marqué cette 7e conférence est développée
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