Rotranslational dynamics of confined water. II. Spectroscopic evidence of confinement effects on the far-infrared spectra of water isotopologues in argon and krypton matrices.

Water molecules trapped in rare gas matrices exhibit conspicuous shifts in their far-infrared (FIR), rotranslational spectral features compared with the corresponding transitions observed in the gas phase. These confinement-induced perturbations have been related not only to the quantization of translational motion but also to the coupling between the orientational and positional degrees of freedom: the rotation-translation coupling (RTC). As the propensity displayed by the nuclear spin isomers (NSI) of water to undergo interconversion in confinement is intimately related to how its nuclear spin degrees of freedom are coupled with those for intra- and intermolecular motions, confinement-induced RTC should also strongly impact the NSI interconversion mechanisms and rates. Insight into the rotranslational dynamics for H2 16O, H2 17O, and H2 18O, confined in argon and krypton matrices, is provided here based on the evolution of rotranslational spectra induced by NSI interconversion while a definitive assignment is provided from the transition energies and intensities calculated using the confined rotor model [Paper I, Wespiser et al., J. Chem. Phys. 156, 074304 (2021)]. In order to build a complete rotranslational energy diagram of confined water, which is fundamental to understand the NSI interconversion rates, the energy difference between the ground ortho and para rotranslational states is derived from the temperature dependence of the intensity ratio of mid-infrared lines emerging from these states. These investigations should provide deeper insight of the factors that control NSI interconversion of water isotopologues under extreme confinement.

Endarterectomy with "systematized" resection anastomosis of carotid bulb, about 240 cases.

OBJECTIVE: Carotid endarterectomy has traditionally been the strategy for the surgical management of carotid stenosis. Alongside the usual techniques, this study presents another technique: endarterectomy with systematized resection-anastomosis. MATERIAL AND METHODS: A retrospective study from January 2006 to December 2018, included all patients managed for carotid stenosis at Meaux hospital with the "endarterectomy with systematized resection-anastomosis" technique. The perioperative death and stroke rate were evaluated according to the judgment criterion "homolateral ischemic stroke and any stroke or perioperative death". Statistical analysis of the data was performed using SPSS software. RESULTS: For 415 carotids operated, we identified 240 managed with this technique. The average age was 71.7±9.6 years, 70% men and 30% women. The main cardiovascular risk factor was hypertension (76.7%), 24.2% of patients had an ischemic heart disease history, 43.7% homolateral ischemic stroke and 29% transient ischemic attack. Bilateral lesions were diagnosed in 6.2% of patients and 7.5% had contralateral occlusion. Carotid stenosis was symptomatic in 52.9% of patients. The average stenosis rate observed was 82.9±8.1% on computed tomography angiogram and 83.7±7.7% on magnetic resonance angiogram. The shunt was used in 45.4% of procedures. The average length of stay was 5.9±2.3 days. All patients had satisfactory results in terms of patency and anatomical appearance on the 1st check. In the post-operative period during the first month, complications occurred in 12.5% of patients (1.6% acute coronary syndrome, 0.8% neurological event, 0.8% death, 0.4% infection, 12.1% hematoma, 1.6% recovery for bleeding). The overall perioperative death and stroke rate was 2.6%. Myocardial infarction and sepsis were the causes of death for the 2 patients in the peri operative period. The mean duration of follow-up was 21.2 months, without any restenosis or occurrence of neurological complications. One patient died beyond the 1st month of follow-up without established cause, and the overall mortality rate was 1.3%. CONCLUSION: Thromboendarterectomy with "systematized" anastomosis resection represents an angioplasty method for carotid stenosis surgical management under visual control.

Infrared Spectroscopy and Density Functional Theory Investigations of the Reactivity of Titanium Atoms with Carbon Monoxide and Water Isolated in Solid Argon: Sequential Evolution from Triplet to Singlet State.

Thermally evaporated titanium atoms reacted with carbon monoxide and water in solid argon at 12 K to produce the HTiOH-CO and HTiOH-(CO)2 molecules, which were characterized using infrared spectroscopy on the basis of CO, Ti, and water concentration variations and of isotopic substitutions. The insertion product, HTiOH, resulting from the reaction of a titanium atom with a water molecule reacts with CO spontaneously to give the HTiOH-CO molecule, which in turn reacts with a second CO molecule to give HTiOH-(CO)2 The density functional theory calculations were performed to elucidate the geometrical and electronic structures and support the spectral assignments. The topological analysis of the charge density within the experimentally observed molecules allowed us to rationalize the coordination sphere as well as the electron pairing on the titanium center.

Vibrational study in neon matrix of H2S-H2O, H2S-(H2O)2, and (H2S)2-H2O complexes. Identification of the two isomers: HOH-SH2 (H2O proton donor) and HSH-OH2 (H2S proton donor).

For the first time, the investigation of water molecules complexed with hydrogen sulfide in solid neon was performed from 80 to 6000 cm-1 using Fourier transform infrared spectroscopy. In the first step, we identify the ν1 and ν3 frequencies of the proton donor in the H2S dimer. From concentration effects and with the help of theoretical results, we have highlighted the presence of the two stable isomers, HOH-SH2 where H2O is the proton donor and HSH-OH2 where H2S is the proton donor. We also identify several transitions for (H2S)2-H2O and H2S-(H2O)2 complexes, the first step of the microsolvation of H2S, and we propose structures for these complexes with the help of theoretical calculations at the second-order Møller-Plesset level.

Infrared Spectroscopy and Density Functional Theory Investigations of PdTi Heterodimer Reactivity with Carbon Monoxide Isolated in Solid Argon.

The reactivity of diatomic palladium-titanium toward carbon monoxide has been studied in solid argon by infrared spectroscopy (Fourier transform infrared) in the carbonyl stretching frequency region. Our technique of sublimation of Ti and Pd atoms from two filaments heated separately allowed the identification of five new molecules. Small polynuclear carbonyl clusters, PdTi(CO) n ( n = 1-3), have been characterized on the basis of isotopic substitutions, metal atom and CO concentration variations, and irradiation effects. Selective irradiation in the visible region leads to conversion between two isomers distinguished by the stretching frequency of the diatomic CO: PdTiCO Ti-eo (νCO = 1908.4 cm-1) and PdTiCO Pd-eo (νCO = 2009.3 cm-1). The density functional theory calculations have been carried out to elucidate the geometrical and electronic structures and support the spectral assignments. The nature of the metal-carbon bonding has been discussed using the topology of the Laplacian of the electron density.

First vibrational investigations of N2O-H2O, N2O-(H2O)2, and (N2O)2-H2O complexes from the far to the near-infrared spectral region by neon matrix isolation and ab initio calculations.

We present for the first time the investigation of water molecules complexed with dinitrogen monoxide, two abundant molecules in atmosphere, in solid neon using Fourier transform infrared (IR) spectroscopy. We identify at least three complexes from concentration effects, N2O-H2O, N2O-(H2O)2, and (N2O)2-H2O, by observation of new absorption bands close to the monomer fundamental modes from the far to the near IR region. We highlight the presence of isomers for the N2O-H2O complex with the help of theoretical calculations at second order Møller-Plesset (MP2) and coupled-cluster single double triple-F12a/aug-cc-pVTZ levels. The observed frequencies for the N2O-(H2O)2 and (N2O)2-H2O complexes are compared with MP2/aug-cc-pVTZ harmonic data. Anharmonic coupling constants have been derived from the observations of overtones and combination bands.

First infrared investigations of OCS-H2O, OCS-(H2O)2, and (OCS)2-H2O complexes isolated in solid neon: Highlighting the presence of two isomers for OCS-H2O.

For the first time, complexes involving carbonyl sulfide (OCS) and water molecules are studied by FTIR in solid neon. Many new absorption bands close to the known fundamental modes for the monomers give evidence for at least three (OCS)n-(H2O)m complexes, noted n:m. With the help of theoretical calculations, two isomers of the 1:1 complex are clearly identified. Concentration effects combined with a detailed vibrational analysis allow for the identification of transitions for the 1:1, 1:2, and 2:1 complexes. Anharmonic coupling constants have been derived from the observations of overtones and combinations.

Conformational Landscape of the 1/1 Diacetyl/Water Complex Investigated by Infrared Spectroscopy and ab Initio Calculations.

The complexes of diacetyl with water have been studied experimentally by Fourier transform infrared (FTIR) spectroscopy coupled to solid neon matrix and supersonic jet, and anharmonic ab initio calculations. The vibrational analysis of neon matrix spectra over the 100-7500 cm-1 infrared range confirms the existence of two nearly isoenergetic one-to-one (1/1) diacetyl-water S1 and S2 isomers already evidenced in a previous argon matrix study. A third form (S3) predicted slightly less stable ( J. Mol. Mod. 2015 , 21 , 214 ) is not observed. The correct agreement obtained between neon matrix and anharmonic calculated vibrational frequencies is exploited in several cases to derive band assignments for the vibrational modes of a specific isomer. Thereafter, theoretical xij anharmonic coupling constants are used for the attribution of combination bands and overtones relative to the 1/1 dimer. Finally, the most stable isomer of the one-to-two (1/2) diacetyl-water complex is identified in the OH stretching region of water on the grounds of comparison of experimental and calculated vibrational shifts between water dimer and the three most stable 1/2 isomers.

Vibrational investigations of CO2-H2O, CO2-(H2O)2, and (CO2)2-H2O complexes isolated in solid neon.

The van der Waals complex of H2O with CO2 has attracted considerable theoretical interest as a typical example of a weak binding complex with a dissociation energy less than 3 kcal/mol. Up to now, experimental vibrational data are sparse. We have studied by FTIR the complexes involving CO2 and water molecules in solid neon. Many new absorption bands close to the well known monomers fundamentals give evidence for at least three (CO2)n-(H2O)m complexes, noted n:m. Concentration effects combined with a detailed vibrational analysis allow for the identification of sixteen, twelve, and five transitions for the 1:1, 1:2, and 2:1 complexes, respectively. Careful examination of the far infrared spectral region allows the assignment of several 1:1 and 1:2 intermolecular modes, confirmed by the observation of combinations of intra + intermolecular transitions, and anharmonic coupling constants have been derived. Our results demonstrate the high sensibility of the solid neon isolation to investigate the hydrogen-bonded complexes in contrast with the gas phase experiments for which two quanta transitions cannot be easily observed.

Modulation of C-reactive protein and plasma omega-6 fatty acid levels by phospholipase A2 gene polymorphisms following a 6-week supplementation with fish oil.

This clinical trial investigated the impact of a six-week supplementation with fish oil and single nucleotide polymorphisms (SNPs) in PLA2G4A and PLA2G6 genes on total omega-6 fatty acid (n-6 FA) levels in plasma phospholipids (PL) and plasma C-reactive protein (CRP) levels in 191 subjects. Interaction effects between SNPs and supplementation modulated total n-6 FAs and CRP levels in both men and women. Associations between SNPs and total n-6 FA levels and between SNPs and CRP levels were identified in men, independently of supplementation. Supplementation decreased total n-6 FAs without affecting plasma CRP levels. Changes in CRP levels correlated positively with changes in total n-6 FAs in men (r=0.25 p=0.01), but not in women. In conclusion, total n-6 FA levels in plasma PL and plasma CRP levels are modulated by SNPs within PLA2G4A and PLA2G6 genes alone or in combination with fish oil supplementation.

Nutrigenomics - perspectives from registered dietitians: a report from the Quebec-wide e-consultation on nutrigenomics among registered dietitians.

BACKGROUND: Not all healthcare professionals are familiar with nutrigenomics. However, they recognise that nutrigenomics has great potential for the development of preventive health approaches. The present study aimed to provide an overall picture of the current situation about nutrigenomics in the practice of registered dietitians (RDs) from the province of Quebec (Canada). METHODS: Three hundred and seventy-three RDs members of the Ordre professionnel des diététistes du Québec completed an online survey that included 34 questions, most of which were closed-ended questions. RESULTS: Overall, 76.9% of RDs knew about nutrigenomics. Among RDs with <5 years of experience, 49.2% knew about genetic testing related to nutrition compared to 11.7% for RDs with over 25 years of experience. Currently, 75.9% of RDs working in clinical nutrition in the public sector consider that they do not have the basic knowledge to integrate nutrigenomics in their practice compared to 62.9% for RDs in private practice. When asked about main limitations of genetic testing related to nutrition, RDs considered that genetic testing does not consider the other determinants of health, that genetic testing and their results have poor accuracy, and that there is a lack of scientific evidence. Concerns remained about ethical and legal aspects and its difficult application as a result of poor understanding and/or interpretation by professionals and/or customers. The high costs of these tests were also noted as a limitation. CONCLUSIONS: Registered dietitians know and are interested in nutrigenomics, especially those with less experience, although they do not feel adequately qualified to integrate findings from nutrigenomics into their practice.

A combined experimental and theoretical study of the Ti2 + N2O reaction.

The reactivity of diatomic titanium with nitrous oxide has been studied in solid neon. Two molecules with the same Ti2-N2O stoichiometry are identified from concentration, temperature, and irradiation effects. The more stable one is characterized by five fundamental vibrational transitions located below 1000 cm(-1), the high frequency one at 946 cm(-1) corresponding to a pure TiO stretching mode. Its structure, a rhombus OTiNTiN with the extra O atom fixed on one Ti, is confirmed by quantum chemical calculations, at the CCSD(T) level, which predict a Cs structure in the singlet state with a Ti-O bond length close to 1.66 Å, two nonequivalent Ti-N distances close to 1.94 and 1.75 Å, and a OTiTi angle of 119.2°. The second Ti2-N2O molecule, only observed after annealing, is easily converted into the first one upon irradiation above 12 000 cm(-1) and its kinetics of photoconversion allows vibrational transitions to be identified. The strongest one located at 2123.4 cm(-1) characterizes an N-N stretching mode. Corresponding ab initio calculations complete this picture with details on the electronic structure and allow us to identify a most adequate density functional to describe the spectroscopic properties of the studied species in a simpler broken-symmetry open-shell DFT context. The theoretical results predict the existence of a metastable product OTi2N2 and correctly account for the observed spectra of the various isotopic varieties.

[A modified Gritti-Stokes amputation for vascular indications in the elderly: futility or utility?]. / Amputation de genou dérivée de la technique de Gritti-Stokes pour artériopathie chronique chez le sujet âgé : est-ce faisable et raisonnable ?

AIM: Major lower limb amputation in elderly patients is a dreaded event with high mortality and morbidity. Peripheral arterial disease is the nearly exclusive etiology. The aim of this retrospective study was to assess the feasibility of through-knee amputation, and the morbidity and mortality risk in the elderly (>65 years). PATIENTS AND METHODS: From January 2000 to October 2010, 65 Gritti-Stokes through-knee amputations were performed in 58 patients (30 women, 28 men; mean age 79 years). Acute limb ischemia was the most common cause (40%). The others indications were: severe peripheral arterial disease with extensive necrotic lesions (19%), diabetic foot ulcers (15%), non-healing below-knee amputation (10%) and vascular graft infection after prosthetic lower extremity bypass surgery (6%). RESULTS: Overall 30-day mortality was 24% (n=14/58). Vascular morbidity was 9% (n=6/65). The mean hospital stay was 31 days (range 3 to 96). The overall healing rate was 78% (n=51/65). Conversion to above-knee amputation for failed Gritti-Stokes amputation was performed in one patient. CONCLUSION: Gritti-Stokes amputation is feasible in the elderly with an acceptable one-month mortality and a satisfactory overall healing rate. Most amputations are necessitated by complications of acute limb ischemia. For this subpopulation, Gritti-Stokes amputation should be the standard amputation level. The data collected in this study provide important information that can be useful before amputation for this population, their families and primary care physicians. Ambulation is an important postoperative goal and a multidisciplinary approach in specialized centers is required to achieve good wound healing rates.

Bonding nature and vibrational signatures of oxirane:(water)(n=1-3). Assessment of the performance of the dispersion-corrected DFT methods compared to the ab initio results and Fourier transform infrared experimental data.

Spectroscopic properties of 1:n complexes (n = 1, 2, and 3) formed between an oxirane molecule and water clusters have been evaluated using experimental techniques (FTIR spectroscopy using a new supersonic jet experiment coupled to the infrared AILES beamline of synchrotron SOLEIL and also cryogenic neon matrix device) and theoretical approaches (SAPT, ab initio, DFT, and topological analyses). From a systematic comparison between the theoretical results (obtained with both wave function based methods and several newly hydrogen bonded adapted functionals) with the available experimental results on the studied compounds, it was concluded that only the wave function based methods (particularly coupled clusters ones) are able to well describe these compounds, while the newly hydrogen bonded adapted functionals (long-range and/or dispersion-corrected ones and also double hybrids) cannot adequately describe all the spectroscopic properties in a systematic way. The MP2 method, although more expensive than DFT, still offers a reliable method to study both isolated molecules and hydrogen bonded complexes provided the contribution of the dispersion energy in total energy is properly taken into account. The nature of interaction between oxirane and water molecules has been analyzed using the symmetry adapted perturbation theory (SAPT) method. It was evidenced that the water-oxirane interaction corresponds to the hydrogen-bonded systems with a large contribution of the dispersion energy. The nature of the oxirane-water bonding has been studied using two topological methods: atoms in molecules and electron-localization function (ELF). Geometrical structures of the titled complexes were rationalized from the spatial arrangement of ELF attractors. Secondary interaction was also accounted for the bond critical points found at H(oxirane)···O(water) bond paths.

The (CH2)2O-H2O hydrogen bonded complex. Ab Initio calculations and Fourier transform infrared spectroscopy from neon matrix and a new supersonic jet experiment coupled to the infrared AILES beamline of synchrotron SOLEIL.

A series of hydrogen bonded complexes involving oxirane and water molecules have been studied. In this paper we report on the vibrational study of the oxirane-water complex (CH(2))(2)O-H(2)O. Neon matrix experiments and ab initio anharmonic vibrational calculations have been performed, providing a consistent set of vibrational frequencies and anharmonic coupling constants. The implementation of a new large flow supersonic jet coupled to the Bruker IFS 125 HR spectrometer at the infrared AILES beamline of the French synchrotron SOLEIL (Jet-AILES) enabled us to record first jet-cooled Fourier transform infrared spectra of oxirane-water complexes at different resolutions down to 0.2 cm(-1). Rovibrational parameters and a lower bound of the predissociation lifetime of 25 ps for the v(OH)(b) = 1 state have been derived from the rovibrational analysis of the ν(OH)(b) band contour recorded at respective rotational temperatures of 12 K (Jet-AILES) and 35 K (LADIR jet).

Pd(2)N(2), a proteiform molecule: Matrix isolation spectroscopy and density functional theory calculations.

The formation of Pd(2)N(2) from the cocondensation of effusive beams of Pd and N(2) in neon and argon matrices is evidenced by absorptions in the range of 2200-1800 cm(-1). In argon, selective irradiation in the near-infrared and visible ranges leads to interconversions between three structures, distinguished by the stretching frequency of the diatomic N(2): Bridged T-shaped (nu(NN) at 1990 cm(-1)), side on (nu(NN) at 2178 cm(-1)) and parallel (nu(NN) at 1823 cm(-1)). For the first two structures, the nu(NN) mode is also accompanied by another signal below 500 cm(-1). An extra feature close to 490 cm(-1), not sensitive to irradiation at lambda(irr)>400 nm and also assignable to a molecule with the same Pd:N(2) stoichiometry (2:1), corresponds to a centrosymmetrical Pd-N-N-Pd structure with an inactive nu(NN) mode close to 2141 cm(-1), as deduced from the observation of a weak signal close to 2630 cm(-1) associated with this species and assignable to the combination nu(NN)+nu(PdN). All these experimental data and their structural implications are fully supported by theoretical calculations [density functional theory (DFT)]. On the basis of this comparative study, we have obtained a reliable theoretical description of the spectroscopic data using the metageneralized gradient approximation functional within the unrestricted DFT (UDFT) formalism for all spin multiplets. We have also searched a stable electronic solution for each multiplet (particularly for the singlet state), in order to account for the nondynamic correlations.

[Pneumothorax surgery]. / Chirurgie des pneumothorax.

Surgery remains the mainstay treatment of recurrent pneumothorax. We recall the therapeutic modalities and indications of surgery in case of pneumothorax. We then compare postoperative outcome, recurrence rate and chronic pain with regard to techniques and surgical approach. Current video-thoracoscopic or axillary thoracotomy procedures for bullous disease with pleurodesis allow a low rate of morbidity and recurrence after primary or secondary spontaneous pneumothorax.

Replacement of a tracheal segment by a mixed graft (aorta and prosthesis): an experimental study in rabbits.

OBJECTIVE: To develop a new graft and to verify its technical feasibility, viability, and ability to reduce the risk of infection by interposition of an aortic segment between the airway and the prosthetic component of the graft. DESIGN: Experimental study. SETTING: Multicentre study, France. ANIMALS: 38 New Zealand rabbits. INTRODUCTION: A 1 cm aortic segment was obtained from the thoracic aorta of a rabbit and cryopreserved or stored at +4 degrees C. The aortic segment, surrounded by a ringed expanded polytetrafluoroethylene (ePTFE) prosthesis was used to replace 1 cm of cervical trachea in two groups of rabbits, either with cryopreserved or fresh aorta. MAIN OUTCOME MEASURES: Macroscopic, microbiological, and histological studies four months later. RESULTS: 12/20 animals in the cryopreserved group survived and 13/18 in those had had fresh aorta inserted. Partial or total necrosis of the aortic muscular layer was replaced by connective tissue, which was a guide for epithelialisation from the anastomoses. CONCLUSION: This new graft is worthy of further investigation, as it is technically feasible and easy to insert.

Videothoracoscopic lung biopsy in diffuse infiltrative lung diseases: a 5-year surgical experience.

BACKGROUND: To establish an accurate diagnosis of diffuse infiltrative lung disease, a surgical lung biopsy may be required. We report our experience with video-thoracoscopic lung biopsy over a period of 5 years. METHODS: From March 1992 through December 1996, videothoracoscopic lung biopsy was performed in 64 patients (17 were women [26.5%]; age, 50.5+/-13 years) with a diagnosis of diffuse infiltrative lung disease of an unknown cause. All patients except one received general anesthesia. Single lung ventilation was used in 61 patients. All lung biopsies were obtained with an endoscopic stapler. RESULTS: Single lung biopsies were performed in 39 patients (61%), two biopsies in 23 patients (36%), and three biopsies in 2 patients. Minithoracotomies were necessary in 10 patients (15.6%) owing to an iatrogenic pulmonary wound (1 patient), extensive pleural adhesions (6 patients), and a stiff lung (3 patients). Postoperative complications were rare and included five discrete pneumothoraces (7.8%), all resolving spontaneously, one prolonged air leak (1.6%), and one hemothorax requiring reoperation. Three preoperatively debilitated patients died (4.7%), 2 with progression of respiratory failure and 1 owing to septic shock. Average chest tube duration was 2.4+/-2 days and average hospital stay was 4.6+/-2.5 days. Lung biopsy contributed to the diagnosis in 59 patients (92%). CONCLUSIONS: Videothoracoscopic lung biopsy using an endoscopic stapler is a safe and effective procedure in most cases and should be performed by trained thoracic surgeons.