Li + HF and Li + HCl Reactions Revisited I: QCT Calculations and Simulation of Experimental Results.

The Li + HF and Li + HCl reactions share some common features. They have the same kinematics, relatively small barrier heights, bent transition states, and are both exothermic when the zero point energy is considered. Nevertheless, the pioneering crossed beam experiments by Lee and co-workers in the 80s (Becker et al., J. Chem. Phys. 1980, 73, 2833) revealed that the dynamics of the two reactions differ significantly, especially at low collision energies. In this work, we present theoretical simulations of their results in the laboratory frame (LAB), based on quasiclassical trajectories and obtained using accurate potential energy surfaces. The calculated LAB angular distributions and time-of-flight spectra agree well with the raw experimental data, although our simulations do not reproduce the experimentally derived center-of-mass (CM) differential cross section and velocity distributions. The latter were derived by forward convolution fitting under the questionable assumption that the CM recoil velocity and scattering angle distribution were uncoupled, while our results show that the coupling between them is relevant. Some important insights into the reaction mechanism discussed in the article by Becker et al. had not been contrasted with those that can be extracted from the theoretical results. Among them, the correlation between the angular momenta involved in the reactions has also been examined. Given the kinematics of both systems, the reagent orbital angular momentum, l, is almost completely transformed into the rotation of the product diatom, j'. However, contrary to the coplanar mechanism proposed in the original paper, we find that the initial and final relative orbital angular momenta are not necessarily parallel. Both reactions are found to be essentially direct, although about 15% of the LiFH complexes live longer than 200 fs.

Universal behavior in complex-mediated reactions: Dynamics of S(1D) + o-D2 → D + SD at low collision energies.

Reactive and elastic cross sections and rate coefficients have been calculated for the S(1D) + D2(v = 0, j = 0) reaction using a modified hyperspherical quantum reactive scattering method. The considered collision energy ranges from the ultracold regime, where only one partial wave is open, up to the Langevin regime, where many of them contribute. This work presents the extension of the quantum calculations, which in a previous study were compared with the experimental results, down to energies in the cold and ultracold domains. Results are analyzed and compared with the universal case of the quantum defect theory by Jachymski et al. [Phys. Rev. Lett. 110, 213202 (2013)]. State-to-state integral and differential cross sections are also shown covering the ranges of low-thermal, cold, and ultracold collision energy regimes. It is found that at E/kB < 1 K, there are substantial departures from the expected statistical behavior and that dynamical features become increasingly important with decreasing collision energy, leading to vibrational excitation.

Effect of probiotics on glucose levels and weight gain in mice exposed to low doses of malathion.

INTRODUCTION: Owing to its ability to reduce the toxicity of environmental pollutants that are risk factors for diabetes and obesity, the use of probiotic bacteria might aid the treatment of these diseases. OBJECTIVE: To determine the effects of chronic exposure to low-dose malathion on weight and glucose levels in mice, as well as to evaluate the protective role of a probiotic supplement. METHODS: Weight and serum glucose levels of four groups of mice (control, malathion-exposed [10 ppm], probiotics and malathion + probiotics) were determined every 10 days for 180 days. RESULTS: Malathion administration induced an increase in weight and glucose levels in the malathion group mice in comparison with the other groups. CONCLUSIONS: Consumption of food contaminated with malathion residues increases glucose levels and favors weight gain, while consumption of probiotics reduces the effects generated by residues in food.

INTRODUCCIÓN: Debido a su capacidad para reducir la toxicidad de contaminantes ambientales que constituyen factores de riesgo de diabetes y obesidad, el uso de bacterias probióticas podría ayudar al tratamiento de esas enfermedades. OBJETIVO: Determinar los efectos de la exposición crónica a malatión a dosis bajas sobre el peso y los niveles de glucosa de ratones, así como evaluar el papel protector de un suplemento probiótico. MÉTODOS: Cada 10 días se determinó el peso y la glucosa sérica de cuatro grupos de ratones (de control, expuestos a malatión (10 ppm), probióticos y malatión + probióticos) durante 180 días. RESULTADOS: La administración de malatión provocó un incremento del peso y los niveles de glucosa en los ratones del grupo con malatión comparados con los demás grupos. CONCLUSIONES: El consumo de alimentos contaminados con residuos de malatión aumenta los niveles de glucosa y favorece el incremento del peso; el consumo de probióticos disminuye los efectos generados por los residuos en los alimentos.

Signature of shape resonances on the differential cross sections of the S(1D)+H2 reaction.

Shape resonances appear when the system is trapped in an internuclear potential well after tunneling through a barrier. They manifest as peaks in the collision energy dependence of the cross section (excitation function), and in many cases, their presence can be observed experimentally. High-resolution crossed-beam experiments on the S(1D) + H2(j = 0) reaction in the 0.81-8.5 meV collision energy range reaction revealed non-monotonic behavior and the presence of oscillations in the reaction cross section as a function of the collision energy, as predicted by quantum mechanical (QM) calculations. In this work, we have analyzed the effect of shape resonances on the differential cross sections for this insertion reaction by performing additional QM calculations. We have found that, in some cases, the resonance gives rise to a large enhancement of extreme backward scattering for specific final states. Our results also show that, in order to yield a significant change in the state-resolved differential cross section, the resonance has to be associated with constructive interference between groups of partial waves, which requires not getting blurred by the participation of many product helicity states.

Development of the Human Biceps Brachii Tendon and Coracoglenoid Ligament (7th-12th Week of Development).

The goal of this study is to clarify the development of the long head of the biceps brachii tendon (LHBT) and to verify the existence and development of the coracoglenoid ligament. Histological preparations of 22 human embryos (7-8 weeks of development) and 43 human fetuses (9-12 weeks of development) were studied bilaterally using a conventional optical microscope. The articular interzone gives rise to the LHBT, glenoid labrum, and articular capsule. During the fetal period, it was observed that in 50 cases (58%), the LHBT originated from both the glenoid labrum and the scapula, while in 36 cases (42%), it originated only from the glenoid labrum. The coracoglenoid ligament, first described by Sappey in 1867, is a constant structure that originates at the base of the coracoid process and projects toward the glenoid labrum zone, which is related to the origin of the LHBT. The coracoglenoid ligament was more easily identifiable in the 36 cases in which the LHBT originated only from the glenoid labrum. We suggest that the coracoglenoid ligament is a constant anatomical structure, is not derived from the articular interzone unlike the LHBT, and contributes to the fixation of the glenoid labrum in the scapula in cases in which the LHBT originated only from the glenoid labrum. We postulate that, when the LHBT is fixed only at the glenoid labrum, alterations in the coracoglenoid ligament could lead to a less sufficient attachment of the glenoid labrum to the scapula which could predispose to a superior labral lesion.

Occipital Condyle Syndrome: A Red Flag for Malignancy. Comprehensive Literature Review and New Case Report.

OBJECTIVE: To perform a literature review of the epidemiology, clinical presentation, diagnostic evaluation, and clinical course of occipital condyle syndrome, including a new case report. BACKGROUND: Occipital condyle syndrome (OCS) is a rare clinical syndrome, consisting of unilateral occipital headache accompanied by ipsilateral hypoglossal palsy. This headache typically radiates to the temporal region, and is triggered by contralateral head rotation. It is usually associated with skull base metastasis, often unrevealed in basic neuroimaging studies. OCS might be the first manifestation of malignancy, and its unfamiliarity can lead to a delay in the diagnosis. METHODS: We performed a systematic literature review using PubMed and Embase for OCS, along with a new case report. RESULTS: A total of 35 cases (mean age 59 years, range 25-77), 24 (70%) men, presented typical unilateral headache followed by ipsilateral hypoglossal palsy from 0 to 150 days after headache presentation. In 16 patients (46%), initial neuroimaging studies were normal. OCS was due to skull base metastasis in 32 cases (91%). In 18 patients (51%), OCS was the first symptom of disease. CONCLUSIONS: OCS represents a warning sign and requires an exhaustive search for underlying neoplasm. An appropriate clinical evaluation can lead to an earlier diagnosis in patients with consistent headache.

Experimental and theoretical study of the collisional quenching of S(1D) by Ar.

We present an experimental and theoretical investigation of the deactivation rate of S(1D) atoms by collisions with argon. Kinetic measurements were performed at temperatures from 5.8 K to 298 K in cold uniform supersonic flows using a CRESU (Cinétique de Réaction en Ecoulement Supersonique Uniforme or Reaction Kinetics in a Uniform Supersonic Flow) apparatus. In order to simulate them, ab initio electronic structure calculations using internally contracted MRCI methodology were performed to describe the interaction. Starting from them, close-coupling calculations were carried out to determine collisional quenching probabilities for the transition S(1D) → S(3P) in the energy range 1-3000 K (1 K ≈ 0.7 cm-1), sufficient to calculate thermal rate coefficients up to 300 K. Stückelberg-like oscillations in the quenching probabilities as a function of the energy are found and interpreted using a semiclassical model. Differences between the temperature dependence of the experimental and theoretical rate coefficients are detected at low temperatures. They are discussed in the light of a study of the high sensitivity of the theoretical results to the potential curves, due to the interference mechanisms which underlie the process.

Comparison Between Chronic Migraine and Temporomandibular Disorders in Pain-Related Disability and Fear-Avoidance Behaviors.

OBJECTIVE: To compare patients with chronic migraine (CM) and chronic temporomandibular disorders (TMD) on disability, pain, and fear avoidance factors and to associate these variables within groups. DESIGN: Descriptive, cross-sectional study. SETTINGS: A neurology department and a temporomandibular disorders consult in a tertiary care center. SUBJECTS: A total of 50 patients with CM and 51 patients with chronic TMD, classified by international criteria classifications. METHODS: The variables evaluated included pain intensity (visual analog scale [VAS]), neck disability (NDI), craniofacial pain and disability (CF-PDI), headache impact (HIT-6), pain catastrophizing (PCS), and kinesiophobia (TSK-11). RESULTS: Statistically significant differences were found between the CM group and the chronic TMD group in CF-PDI (P < 0.001), PCS (P = 0.03), and HIT-6 (P < 0.001); however, there were no differences between the CM group and the VAS, NDI, and TSK-11 groups (P > 0.05). For the chronic TMD group, the combination of NDI and TSK-11 was a significant covariate model of CF-PDI (adjusted R2 = 0.34). In the CM group, the regression model showed that NDI was a significant predictive factor for HIT-6 (adjusted R2 = 0.19). CONCLUSIONS: Differences between the CM group and the chronic TMD group were found in craniofacial pain and disability, pain catastrophizing, and headache impact, but they were similar for pain intensity, neck disability, and kinesiophobia. Neck disability and kinesiophobia were covariates of craniofacial pain and disability (34% of variance) for chronic TMD. In the CM group, neck disability was a predictive factor for headache impact (19.3% of variance).

S((1)D) + ortho-D2 Reaction Dynamics at Low Collision Energies: Complementary Crossed Molecular Beam Experiments and Theoretical Investigations.

The excitation function of the S((1)D) + D2 reaction was determined in a crossed molecular beam apparatus for collision energies ranging from 1817 to 47 J mol(-1) in the near-cold regime. A very good overall agreement was found between experimental data and the theoretical results obtained using the ab initio potential energy surface built by Ho and coworkers and different methods: time-independent quantum dynamics (QM), semiclassical mean potential capture theory (sc-MPCT), and quasi-classical trajectories (QCT). The general trend of the experimental excitation function is well reproduced in most of the range by a simple capture calculation with an R(-6) dispersion potential. The present results are discussed in the light of previous studies on the isotopic variants S((1)D) + H2 and HD.

Effect of anticoagulation on cardioembolic stroke severity, outcomes and response to intravenous thrombolysis.

Our objective was to evaluate the effect of anticoagulation on cardioembolic stroke (CS) severity, outcomes, and response to intravenous thrombolysis (IVT). Observational study of CS patients admitted to a Stroke Center (2010-2013). The sample was classified into three groups based on pre-stroke oral anticoagulants (OAC) treatment (all acenocumarol) and the international normalized ratio (INR) on admission: (1) non-anticoagulated or anticoagulated patients with INR <1.5, (2) anticoagulated with INR 1.5-1.9 and (3) anticoagulated with INR ≥2. We compared demographic data, vascular risk factors, symptomatic intracranial hemorrhage, severity on admission (NIHSS) and 3 month outcomes (mRS). Overall 475 patients were included, 47.2 % male, mean age 75.5 (SD 10.7) years old, 31.8 % were on OAC. 76 % belonged to the INR <1.5 group, 13.3 % to the INR 1.5-1.9 and 10.5 % to the INR >2. 35 %of patients received IVT. Multivariate analyses showed that an INR ≥2 on admission was a factor associated with a higher probability of mild stroke (NIHSS <10) (OR 2.026, 95 % CI 1.006-4.082). Previous OAC in general (OR 2.109, 95 % CI 1.173-3.789) as well as INR 1.5-1.9 (OR 3.676, 95 % CI 1.510-8.946) were associated with favorable outcomes (mRS ≤2). OAC was not related to stroke outcomes in the subgroup of IVT patients. Therapeutic OAC levels are associated with lesser CS severity, and prior OAC treatment with favorable outcomes. In this study, OAC are not related with response to IVT.

Cold and ultracold dynamics of the barrierless D(+) + H2 reaction: Quantum reactive calculations for ∼R(-4) long range interaction potentials.

Quantum reactive and elastic cross sections and rate coefficients have been calculated for D(+) + H2 (v = 0, j = 0) collisions in the energy range from 10(-8) K (deep ultracold regime), where only one partial wave is open, to 150 K (Langevin regime) where many of them contribute. In systems involving ions, the ∼R(-4) behavior extends the interaction up to extremely long distances, requiring a special treatment. To this purpose, we have used a modified version of the hyperspherical quantum reactive scattering method, which allows the propagations up to distances of 10(5) a0 needed to converge the elastic cross sections. Interpolation procedures are also proposed which may reduce the cost of exact dynamical calculations at such low energies. Calculations have been carried out on the PES by Velilla et al. [J. Chem. Phys. 129, 084307 (2008)] which accurately reproduces the long range interactions. Results on its prequel, the PES by Aguado et al. [J. Chem. Phys. 112, 1240 (2000)], are also shown in order to emphasize the significance of the inclusion of the long range interactions. The calculated reaction rate coefficient changes less than one order of magnitude in a collision energy range of ten orders of magnitude, and it is found in very good agreement with the available experimental data in the region where they exist (10-100 K). State-to-state reaction probabilities are also provided which show that for each partial wave, the distribution of HD final states remains essentially constant below 1 K.

Intravenous thrombolysis in stroke patients under 55 years of age: is there a different effect according to etiology and severity?

The effect of intravenous thrombolysis (IVT) according to etiology and stroke severity in young patients with ischemic stroke (IS) has not been described previously. To analyze the effect of IVT in young patients with IS according to etiological subtype and stroke severity. Observational study with inclusion of IS patients under 55 years of age (2007-2012). Two groups were compared according to IVT treatment. Favorable outcomes were defined as 3 months modified Rankin Scale ≤2. Multivariate analyses were performed to determine those factors independently associated with favorable outcomes, and subgroup analyses were conducted to assess the effect of IVT according to etiological stroke subtype and severity on admission, adjusted for other prognostic variables. We evaluated 262 patients. 63 (24%) received IVT. The mean age and the sex distribution were similar in the IVT treated and the non-treated groups. Multivariate analyses showed that IVT was associated with a higher probability of favorable outcome (OR, 95% CI: 4.652, 1.294-16.722) whereas artery dissection (OR, 95% CI: 0.191, 0.056-0.654) and NIHSS (OR, 95% CI: 0.727, 0.664-0.797) were associated with a lower probability of a favorable outcome. The subgroup analysis showed that the beneficial effect of IVT on outcomes was significant in moderate-severe strokes (NIHSS ≥8) (OR, 95% CI: 3.782, 1.095-13.069) and in cardioembolism (OR, 95% CI: 41.887, 1.001-1751.596). In IS patients under 55 years of age, those with moderate-severe strokes benefit more from IVT than those with mild strokes. Cardioembolic infarctions may benefit more from IV tPA than other etiologies.

Acute ischemic stroke patients with diabetes should not be excluded from intravenous thrombolysis.

The benefit of intravenous thrombolysis (IVT) has been questioned for patients with diabetes mellitus (DM) in cases of acute ischemic stroke (IS). Our objective was to analyze the differences in outcome according to prior diagnosis of DM and the use or not of IVT. Observational study with inclusion of consecutive IS patients admitted to an stroke unit. Demographic data, vascular risk factors, comorbidity, stroke severity and 3-month follow-up outcome (modified Rankin Scale) were compared according to prior diagnosis of DM and the use or not of IVT. A total of 1,139 IS patients were admitted; 283 (24.8%) patients had a diagnosis of DM, and 261 were IVT treated (23.2% of the group without DM and 21.9% of the DM group). The IVT-treated patients with DM were older, had more comorbidities and had higher glucose levels on admission than those without DM and than IVT-treated patients. No significant differences in stroke severity, hemorrhagic transformation, in-hospital mortality or outcome at 3 months were found. The logistic regression analysis showed that stroke severity was associated with a higher risk of a poor outcome in IVT-treated patients, with no significant effect from DM after adjustment for confounders. Moreover, IVT was independently associated with a lower risk of poor outcome in DM patients (OR 0.49; 95% CI 0.31-0.76; P = .002). DM patients should not be excluded from IVT, because DM is not associated with a poor outcome after IVT and this treatment is clearly beneficial for DM patients as compared with DM patients not treated with IVT.

Reparative therapy for acute ischemic stroke with allogeneic mesenchymal stem cells from adipose tissue: a safety assessment: a phase II randomized, double-blind, placebo-controlled, single-center, pilot clinical trial.

BACKGROUND: Few studies have evaluated the possible beneficial effect of the administration of stem cells in the early stages of stroke. Intravenous administration of allogeneic mesenchymal stem cells (MSCs) from adipose tissue in patients with acute stroke could be a safe therapy for promoting neurovascular unit repair, consequently supporting better functional recovery. We aim to assess the safety and efficacy of MSC administration and evaluate its potential as a treatment for cerebral protection and repair. MATERIALS: A Phase IIa, prospective, randomized, double-blind, placebo-controlled, single-center, pilot clinical trial. Twenty patients presenting acute ischemic stroke will be randomized in a 1:1 proportion to treatment with allogeneic MSCs from adipose tissue or to placebo (or vehicle) administered as a single intravenous dose within the first 2 weeks after the onset of stroke symptoms. The patients will be followed up for 2 years. Primary outcomes for safety analysis: adverse events (AEs) and serious AEs; neurologic and systemic complications, and tumor development. Secondary outcomes for efficacy analysis: modified Rankin Scale; NIHSS; infarct size; and biochemical markers of brain repair (vascular endothelial growth factor, brain-derived neurotrophic factor, and matrix metalloproteinases 9). RESULTS AND CONCLUSIONS: To our knowledge, this is the first, phase II, pilot clinical trial to investigate the safety and efficacy of intravenous administration of allogeneic MSCs from adipose tissue within the first 2 weeks of stroke. In addition, its results will help us define the best criteria for a future phase III study.

[New insights into the role of pholcodine in the treatment of cough in 2013?]. / Quel rôle pour la pholcodine dans le traitement de la toux, en 2013 ?

Pholcodine is an opioid that has been widely used worldwide since 1950 for the treatment of non-productive cough in children and adults. The results of early preclinical studies but also those of recent clinical trials have shown the antitussive efficacy of pholcodine to be superior to that of codeine, of longer duration, and with an equivalent or safer toxicity profile. Also, there is no risk of addiction. Concern had been raised over a possible cross-sensitisation with neuromuscular blocking agents. While a recent assessment of the available data by the European Medicines Agency (EMA) has confirmed the favourable risk-benefit ratio of pholcodine, further studies are needed to clear this point.

[Not Available]. / Quel rôle pour la pholcodine dans le traitement de la toux, en 2013 ?

Pholcodine is an opioid that has been widely used worldwide since 1950 for the treatment of non-productive cough in children and adults. The results of early preclinical studies but also those of recent clinical trials have shown the antitussive efficacy of pholcodine to be superior to that of codeine, of longer duration, and with an equivalent or safer toxicity profile. Also, there is no risk of addiction. Concern had been raised over a possible cross-sensitisation with neuromuscular blocking agents. While a recent assessment of the available data by the European Medicines Agency (EMA) has confirmed the favourable risk-benefit ratio of pholcodine, further studies are needed to clear this point.

Dynamics of the S(1D2)+HD(j=0) reaction at collision energies approaching the cold regime: a stringent test for theory.

We report integral cross sections for the S(1D2)+HD(j=0)→DS+H and HS+D reaction channels obtained through crossed-beam experiments reaching collision energies as low as 0.46 meV and from adiabatic time-independent quantum-mechanical calculations. While good overall agreement with experiment at energies above 10 meV is observed, neither the product channel branching ratio nor the low-energy resonancelike features in the HS+D channel can be theoretically reproduced. A nonadiabatic treatment employing highly accurate singlet and triplet potential energy surfaces is clearly needed to resolve the complex nature of the reaction dynamics.

Rate coefficients from quantum and quasi-classical cumulative reaction probabilities for the S(1D) + H2 reaction.

Cumulative reaction probabilities (CRPs) at various total angular momenta have been calculated for the barrierless reaction S((1)D) + H(2) → SH + H at total energies up to 1.2 eV using three different theoretical approaches: time-independent quantum mechanics (QM), quasiclassical trajectories (QCT), and statistical quasiclassical trajectories (SQCT). The calculations have been carried out on the widely used potential energy surface (PES) by Ho et al. [J. Chem. Phys. 116, 4124 (2002)] as well as on the recent PES developed by Song et al. [J. Phys. Chem. A 113, 9213 (2009)]. The results show that the differences between these two PES are relatively minor and mostly related to the different topologies of the well. In addition, the agreement between the three theoretical methodologies is good, even for the highest total angular momenta and energies. In particular, the good accordance between the CRPs obtained with dynamical methods (QM and QCT) and the statistical model (SQCT) indicates that the reaction can be considered statistical in the whole range of energies in contrast with the findings for other prototypical barrierless reactions. In addition, total CRPs and rate coefficients in the range of 20-1000 K have been calculated using the QCT and SQCT methods and have been found somewhat smaller than the experimental total removal rates of S((1)D).

Low-Energy Pulsed-Laser Welding as a Root Pass in a GMAW Joint: An Investigation on the Microstructure and Mechanical Properties.

Root pass is a fundamental step in multi-pass welding. In gas metal arc welding (GMAW), the weld bead qualities depend on the process parameters, filler materials, and welder abilities. This work investigates the effect of a Nd: YAG pulsed laser as a first pass to reduce the welders' reliance on the AH36 low-alloy steel with 5.5 mm thickness. This autogenous automatable process delivers reduced thermal impact due to the concentrated high-energy source, pulse overlap, and higher penetration depth-to-power ratio than continuous lasers. The outcomes indicate that the PL as a root welding generated a small HAZ compared to the GMAW condition. In addition, the subsequent arc passes positively affected the microstructure, reducing the hardness from around 500 to 230 HV. The PL + GMAW achieved similar strength results to the GMAW, although its Charpy impact values at -50 °C were around 15% lower than the arc condition.

Reaching the cold regime: S((1)D) + H2 and the role of long-range interactions in open shell reactive collisions.

Reactive cross-sections for the collision of open shell S((1)D) atoms with ortho- and para-hydrogen, in the kinetic energy range 1-120 K, have been calculated using the hyperspherical quantum reactive scattering method developed by Launay et al. [Chem. Phys. Lett., 1990, 169, 473]. Short-range interactions, described using the ab initio potential energy surface by Ho et al. [J. Chem. Phys., 2002, 116, 4124], were complemented with an accurate description of the long-range interactions, where the main electrostatic (∼R(-5)) and dispersion (∼R(-6)) contributions were considered. This allows the comparison with recent experimental measurements of rate constants and excitation functions for the title reaction at low temperatures [Berteloite et al., Phys. Rev. Lett., 2010, 105, 203201]. The agreement is fairly good. The behavior in the considered energy range can be understood on average in terms of a classical Langevin (capture) model, where the centrifugal barriers determine the amount of reactive flux which reaches the barrierless transition state. Additionally, the structure of the van der Waals well provides temporal trapping at intermediate intermolecular distances thus allowing the system to find its way to the reaction at some classically-forbidden energies. Interestingly, the cross-section for para-hydrogen shows clearly oscillating features associated with the opening of new partial waves and with shape resonances which may be amenable to experimental detection.