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Abstract: Six clinical studies of chronic electrical modulation of deep brain circuits published between 1968 and 2010 have reported effects in 55 vegetative or minimally conscious patients. The rationale stimulation was to activate the cortex through the reticular-thalamic complex, comprising the tegmental ascending reticular activating system and its thalamic targets. The most frequent intended target was the central intralaminar zone and adjacent nuclei. Hassler et al. also proposed to modulate the pallidum as part of the arousal and wakefulness system. Stimulation frequency varied from 8Hz to 250Hz. Most patients improved, although in a limited way. Schiff et al. found correlations between central thalamus stimulation and arousal and conscious behaviours. Other treatments that have offered some clinical benefit include drugs, repetitive magnetic transcranial stimulation, median nerve stimulation, stimulation of dorsal column of the upper cervical spinal cord, and stimulation of the fronto-parietal cortex. No one treatment has emerged as a gold standard for practice, which is why clinical trials are still on-going. Further clinical studies are needed to decipher the altered dynamics of neuronal network circuits in patients suffering from severe disorders of consciousness as a step towards novel therapeutic strategies. [Copyright &y& Elsevier]

This study identifies positive and negative factors associated with physician well being. We collected two sets of data from physicians at a university-based Department of Medicine in Western Canada. First, we conducted exploratory, in-depth interviews with 54 physicians to identify factors associated with their well being. Participants explained that certain aspects of their work are demanding and negatively related to their well being, whereas other 5 factors are more enabling and contribute positively. Second, we mailed a structured questionnaire including measures of the key factors identified in the physician interviews to all physicians in the same Department of Medicine. Multivariate analysis was used to assess the extent to which the factors identified in the interviews are significantly related to physicians' well being. The findings show the importance of co-worker support, both in terms of being directly related to physician well being as well as buffering the negative effects of work demands. We discuss several important implications for physicians and the organizations that employ them in understanding the factors related to physician well being. In addition, patient interactions appear to be both a key source of stress and a major source of satisfaction in physicians' daily work lives. [ABSTRACT FROM AUTHOR]

Abstract: Comfort, productivity and quality of life of living beings are strongly influenced by the physical properties of their microenvironment. To guarantee an optimal microenvironment, the supply and distribution of fresh air must be controlled. Therefore, on-line airflow pattern measurement and control are crucial elements. A new concept of an airflow pattern sensor, based on the measurement of the temperature distribution at air inlet, was tested and validated in two test installations at different scale. The sensor allowed a prediction of the airflow pattern centreline with a maximum deviation of 0.22m at 1.5m from inlet and a deviation of 0.53m at 3.5m from inlet. Integrating this sensor in climate control equipment will improve the distribution of fresh air within the ventilated space. [Copyright &y& Elsevier]

In situ observations indicate the presence of external/magnetosheath-like plasma inside the magnetosphere. Two-point measurements show that a positive density gradient develops inside these plasma irregularities such that the density increases from the front edge (closer to the Earth) to the trailing edge. It is shown that this effect can be explained by the expansion of the plasma blobs or plasmoids along magnetic field lines. Impulsively injected magnetosheath density irregularities may be stopped before they fully penetrate inside the magnetosphere and become isolated plasma blobs/islands. Furthermore, it is argued that non-detachment of these intruding plasma islands from the magnetopause does not rule out the impulsive penetration (IP) mechanism as a candidate for explaining the presence of magnetosheath plasma inside the magnetosphere. The main features of the kinetic description of the IP mechanism are briefly recalled first. [Copyright &y& Elsevier]

La radiochirurgie pour le traitement de la névralgie du trijumeau délivre une très forte dose en une seule séance, sur quelques millimètres, au niveau d'un isocentre unique placé le long du nerf. Nous présentons ici les différentes étapes qui ont été réalisées pour valider des petits faisceaux par collimateurs coniques, et rapportons les résultats cliniques des premiers patients pris en charge sur Novalis Tx® sans cadre invasif. Nous avons d'abord été évalué l'exactitude géométrique des collimateurs coniques de 4 et 6 mm à l'aide de tests de Winston-Lutz ; puis l'acquisition des données dosimétriques a été réalisée grâce à des détecteurs de haute résolution spatiale (microdiamant PTW 60019 et une diode E PTW 60017). Les facteurs correctifs du rapport TRS no 483 ont été appliqués pour le calcul des facteurs d'ouverture du collimateur. Ces données dosimétriques ont ensuite été comparées avec les données implémentées dans le système de planification de traitement iPlan®. Puis des tests end-to-end ont permis de contrôler l'ensemble du processus de traitement à l'aide d'un fantôme anthropomorphique stereotactic end-to-end verification. Entre 2020 et 2022, 18 patients ont été traités pour névralgie trigéminale réfractaire sur Novalis Tx® sans cadre invasif avec repositionnement par Exactrac®. Dix-sept patients ont été évalués (un a été perdu de vue) à l'aide du score du Barrow Neurological Institute pour l'évaluation de la douleur, et par IRM avec un suivi médian de 12 mois. Les critères de qualité d'exactitude géométrique et dosimétriques ont été atteints pour le cône de 6 mm mais pas pour le cône de 4 mm. Tous les patients ont été traités avec un cône de 6 mm avec une dose de 90 Gy prescrite à l'isocentre ciblée au niveau de la root entry zone. Le contrôle initial de la douleur a été obtenu chez 70,5 % de nos patients, et 53 % ont conservé ce contrôle avec un suivi médian de 12 mois. Toutes les récidives sont survenues dans un délai de 3 à 6 mois après la radiochirurgie. Aucune toxicité n'a été observée sur le tronc cérébral. Trois patients ont eu une hypoesthésie faciale non invalidante. Le traitement des névralgies trigéminales sur accélérateur linéaire dédié est un traitement de haute technicité dont l'exactitude et la sécurité est primordiale. Les mesures physiques ont permis la mise en service de la technique avec un cône de 6 mm. Nos premiers résultats cliniques sont conformes aux données de la littérature. Radiosurgery for the treatment of trigeminal neuralgia delivers a very high dose in a single fraction, over a few millimeters, at a single isocenter placed along the nerve. We present here the different steps that have been performed to validate small beams by conical collimators, and report the clinical results of the first patients treated on Novalis Tx®, frameless. First, the geometric accuracy of 4 and 6 mm conical collimators was evaluated using Winston-Lutz tests; then dosimetric data acquisition was performed using high spatial resolution detectors (PTW 60019 microdiamond and a PTW 60017 E-diode). The corrective factors of the TRS 483 report were applied to calculate the collimator aperture factors. These dosimetric data were then compared with the data implemented in the iPlan® treatment planning system. Then end-to-end tests were performed to control the entire treatment process using an anthropomorphic phantom "STEEV". Between 2020 and 2022, 18 patients were treated for refractory trigeminal neuralgia on Novalis Tx®, frameless, with Exactrac® repositioning. A total of 17 patients were evaluated (one was lost to follow-up) using the BNI score for pain assessment and MRI with a median follow-up of 12 months. The quality criteria of geometric and dosimetric accuracy were met for the 6-mm cone but not for the 4-mm cone. All patients were treated with a 6-mm cone with a dose of 90 Gy prescribed at the isocenter at the root entry zone. Initial pain control was obtained in 70.5% of our patients, and 53% maintained pain control with a median follow-up of 12 months. All recurrences occurred within 3 to 6 months after radiosurgery. No brainstem toxicity was observed. Six patients had non-disabling facial hypoesthesia, half of whom already had pretreatment hypoesthesia. The treatment of trigeminal neuralgia on a dedicated linear accelerator is a highly technical treatment whose accuracy and safety are paramount. The physical measurements allowed the commissioning of the technique with a 6 mm cone. Our first clinical results are in accordance with the literature. [ABSTRACT FROM AUTHOR]

We and others have shown central roles of the Na(+)/H(+) exchanger NHE1 in cell motility. The aim of this study was to determine the roles of NHE1 and of the Na(+), HCO(3)(-) cotransporter NBCn1 in motility of serum-starved MCF-7 breast cancer cells expressing constitutively active ErbB2 (ΔNErbB2). ΔNErbB2 expression elicited NBCn1 upregulation, Ser(703)-phosphorylation of NHE1, and NHE1-inhibitor (EIPA)-sensitive pericellular acidification, in conjunction with increased expression of β1 integrin and ERM proteins. Active ERM proteins and NHE1 colocalized strongly to invadopodial rosettes, the diameter of which was increased by ΔNErbB2. Adhesion and migration on collagen-I were augmented by ΔNErbB2, unaffected by the NBC inhibitor S0859, and further stimulated by EIPA in a manner potentiated by PI3K-Akt-inhibition. These findings demonstrate that NHE1 inhibition can enhance cancer cell motility, adding an important facet to the understanding of NHE1 in cancer. [ABSTRACT FROM AUTHOR]

Abstract: The structures of the sodium complexes of oligoglycines (GG–Na+, GGG–Na+) and oligoalanines (AA–Na+, AAA–Na+) have been studied by infrared spectroscopy in the gas phase. Two different experimental set-ups have been used to generate, trap and analyze the ions. In the first, the complexes were generated by MALDI and analyzed in the cell of a home built FT-ICR mass spectrometer. In the second an external electrospray source was coupled to a Paul type ion trap. Following their trapping, the ions are irradiated in both cases with intense, tunable infrared light in the 1000–2000cm−1 range, leading to sodium ion detachment and ion fragmentation via the absorption of multiple photons. The resulting experimental spectra are compared to theoretical linear absorption spectra to assign structures. In agreement with calculations, peptide attachment to Na+ is found to have a strong structuring effect: the lowest energy structures involve binding of all carbonyl oxygens to the cation. Detailed comparison of experimental and computed spectra shows that the IRMPD spectroscopy of such gaseous ions allows the differentiation between structures which do not have the same number of carbonyl oxygens bound to Na+, and structures in which the peptide is either wrapped around the ion or capped by it. [Copyright &y& Elsevier]

In the incubation process of domestic avian eggs, the development of the embryo is mainly influenced by the physical microenvironment around the egg. Only small spatiotemporal deviations in the optimal incubator air temperature are allowed to optimize hatchability and hatching quality. The temperature of the embryo depends on 3 factors: (1) the air temperature, (2) the exchange of heat between the egg and its microenvironment and (3) the time-variable heat production of the embryo. Theoretical estimates on the heat exchange between an egg and its physical microenvironment are approximated using equations that assume an approximate spherical shape for eggs. The objective of this research was to determine the heat transfer between the eggshell and its microenvironment and then compare this value to various theoretical estimates. By using experimental data, the overall and the convective heat transfer coefficients were determined as a function of heat production, air humidity, air speed, and air temperature. Heat transfer was not affected by air humidity but solely by air temperature, embryonic heat generation, and air speed and flow around eggs. Also, heat transfer in forced-air incubators occurs mainly by convective heat loss, which is dependent on the speed of airflow. A vertical airflow is more efficient than a horizontal airflow in transferring heat from the egg. We showed that describing an egg as a sphere under estimated convective heat transfer by 33% and was, therefore, too simplistic to accurately assess actual heat transfer from real eggs. [ABSTRACT FROM AUTHOR]

Vibrationally excited N2H+ and N2D+ ions with internal energies of at least 1.3 eV have been produced by electron ionization of a mixture of N2 and H2 (or D2). Their radiative overall lifetime has been determined using the monitor ion technique in a triple cell ICR spectrometer.Theoretical calculation of the vibrational energy levels up to 2.3 eV and of the radiative lifetimes for the fundamental transition of the three normal modes of each isotopomer has been performed in order to help the qualitative analysis of the experimental results.Excitation of ν1 stretching mode is quickly relaxed and is not observed in our experimental conditions. The measured overall lifetimes correspond mainly to excitation of ν2 bending mode. Excitation of the ν3 stretching above v=2 for N2H+ and v=3 for N2D+ seems to be negligible. [Copyright &y& Elsevier]

Il existe un consensus depuis 2004 pour proposer une dose de 12 à 13 Gy sur l'isodose d'enveloppe afin de limiter les taux de complication pour les radiochirurgies stéréotaxiques des schwannomes vestibulaires. L'objectif était d'évaluer rétrospectivement l'efficacité et la toxicité de la radiochirurgie stéréotaxique des schwannomes vestibulaires traités sur accélérateur linéaire avec différentes doses d'enveloppe. De 1995 à 2019, chez 97 patients, des schwannomes vestibulaires de stade 1 (1 %), 2 (56 %), 3 (21,5 %) et 4 (21,5 %) ont été traités par irradiation stéréotaxique par accélérateur linéaire avec cadre invasif avant février 2014 (62 %), puis sans cadre (38 %). La dose médiane prescrite en enveloppe était de 14 Gy (extrêmes : 12-16 Gy) avant 2006, puis de 11 Gy pour tous les patients (61)(protocole de désescalade institutionnel). Le volume moyen tumoral était 1,96 cm3 (extrêmes : 0,1–13,2 cm3). Le suivi médian était 8,2 ans. Pour les 97 patients pris en charge, le taux de contrôle local était de 100 %, 98,4 % et 95,6 % respectivement à 2, 5 et 10 ans. Le taux de contrôle local pour une dose d'enveloppe de 11 Gy était de 100 % à 10 ans contre 100 %, 97 % et 94 % respectivement à 2, 5 et 10 ans pour la dose d'enveloppe d'au moins 12 Gy (p = 0,35). Une augmentation transitoire tumorale pouvait être observée jusqu'à 2 ans (12,4 % sur l'IRM à 6 mois et 3,1 % à 1 an). À 5 ans, le taux de toxicité était de 5,5 % sur le nerf facial (1,7 % pour une dose d'enveloppe de 11 Gy contre 11,2 % pour 12 Gy avec p = 0,11, contre 11,2 % si la dose d'enveloppe était supérieure ou égale à 12 Gy avec p = 0,05) et 8,6 % sur le nerf trijumeau (3,7 % si la dose d'enveloppe était de 11 Gy contre 0 % pour 12 Gy avec p = 0,51, contre 14,2 % pour une dose d'enveloppe supérieure ou égale à 12 Gy avec p = 0,11). Le taux de baisse de l'audition chez les patients ayant initialement une audition utile était 41,4 % à 5 ans (42,3 % si la dose d'enveloppe était de 11 Gy contre 44,4 % si elle était supérieure ou égale à 12 Gy, p = 0,71). Une diminution de la dose d'enveloppe à 11 Gy pour les radiochirurgies stéréotaxiques de schwannomes vestibulaires permet de conserver le même taux de contrôle local (100 % à 10 ans) mais avec une réduction du taux de toxicité. [ABSTRACT FROM AUTHOR]

Objectif de l’étude Évaluer l’efficacité et la toxicité d’un second traitement par radiochirurgie pour une récidive locale d’une même métastase cérébrale. Patients et méthodes De novembre 1995 à février 2016, 33 atteints de 39 métastases cérébrales ont été réirradiés par radiochirurgie pour une récidive locale après échec d’une première. Trente-six traitements ont été délivré en séance unique de dose médiane de 20 Gy. Trois en trois séances de 11 Gy. Toutes les métastases étaient situées en zone peu fonctionnelle. À partir de 2000, l’irradiation a été délivrée par un accélérateur linéaire équipé d’un collimateur micomultilames avec une technique d’arcthérapie dynamique. Résultats Après la deuxième radiochirugie, les taux de contrôle local à 6 mois et un an étaient respectivement de 85,7 % et 73,3 %. En analyse multifavctorielle, le volume tumoral macroscopique (GTV) (< 3 cm 3 ) était corrélé avec le taux de contrôle local ( p = 0,01). Les taux de survie globale à un et deux ans après la deuxième radiochirugie étaient respectivement de 68 % et 29 % et la durée médiane de survie de 14,2 mois. En analyse multifactorille, la survie globale était corrélée avec le statut du cancer primitif : réponse complète contre stable, progression ou réponse partielle ( p = 0,04). Au total, 14 (35,9 %) patients ont souffert d’effets secondaires : de l’œdème, de la radionécrose et des hémorragies ont été respectivement retrouvés chez cinq (13 %), quatre (10 %), et cinq (13 %) patients. En analyse unifactorielle, la toxicité étaient associée à un GTV de plus de 7 cm 3 ( p = 0,02). Aucun patient n’a souffert de toxicité symptomatique et aucun décès n’était imputable à la toxicité. Conclusion Réirradiation par radiochirugie une récidive locale de métstase cérébrale est une technique efficace et la toxicité est acceptables lorsque cette métastase est située dans une zone peu fonctionnelle. Cette technique peut être envisagée chez les patients en situation de bon contrôle extracérébral. [ABSTRACT FROM AUTHOR]

The fate of oxo-polymers in nature is strongly dependent on environmental conditions, mainly on the intensity and duration of sunshine, which vary with the season and the climate. In this work, we report the effect of different scenarii on the production and the molecular composition of oligomers released from oxo-biodegradable HDPE films. Under our experimental conditions, the duration of accelerated weathering corresponded to a period of 3 months to 3 years of exposure to outside conditions under temperate climate. In addition, the oligomers were extracted in three different solvents: i) water to mimics the natural environment; ii) acetone and chloroform to identify oligomers trapped in the polymer matrix. The combination of high-resolution mass spectrometry and 1 H NMR spectroscopy gives an extensive picture of the relative concentrations and the structural compositions of the extracted oligomers in the different tested conditions. In particular, the masses, the number of oxygen and carbon atoms could be determined for up to 2283 molecules. Globally the concentration and the size of oligomers increased with the duration of extraction, the level of aging of the polymer and the use of non-polar solvents. Surprisingly, the presence of highly oxidized molecules in acetone and chloroform extract, suggested an important swelling of HPDE films in these solvents and a better diffusion of these oligomers in the matrix. In nature, the biodegradability of oligomers could result from processes occurring both at the molecular (oxidation) and the macromolecular (diffusion and release) levels. [ABSTRACT FROM AUTHOR]

The objective of this work was to develop a new approach to assess the specificity and the efficiency of biodegradation of oxidized oligomers extracted from aged HDPE polyethylene films and to bring insight on the mechanisms occurring during biodegradation. 1 H NMR spectroscopy and LC Orbitrap™ mass spectrometry were combined together with data processing using Kendrick mass defect calculation and Van Krevelen Diagram. We showed that the molecular weight of extracted oligomers was lower than 850 Da with maximum chain length of 55 carbon atoms. The oligomers were divided into 11 classes of molecules with different oxidation state ranging from 0 to 10. All classes included series of chemically related compounds including up to 19 molecules. 95% of the soluble oligomers were assimilated by a strain of Rhodococcus rhodocchrous after 240 days of incubation. Large highly oxidized molecules completely disappeared while the other classes of molecules were still represented. Molecules containing 0–1 oxygen atom were less degraded. A strong shift to smaller molecules (<450 Da, 25 carbon atoms) was observed suggesting that longer molecules disappeared more rapidly than the smaller ones. It opens new perspectives on biodegradation processes as not only intracellular β-oxidation must be considered but also extracellular mechanisms leading to chain cleavages. [ABSTRACT FROM AUTHOR]

• At 50% vol. of ethanol in the fuel and above the emissions of total unburnt hydrocarbons increase strongly. • The number and size of particles are unaffected by the increase in fuel ethanol content. • Risk of increased NOx emissions for Euro 6d-temp internal combustion engines. • Ethanol content of 50% vol. and above lead to an increase of aldehyde emissions, ethylene, methane, and ethanol. • Both analytical techniques (gas chromatography vs time-resolved mass spectrometry) exhibited similar trends regarding non-regulated emissions. This study evaluates the impact of ethanol content on both regulated and non-regulated emissions with recent vehicle technologies. The three vehicles used here are complying with Euro 6d-temp or Euro 6c emission standards and are adapted to variable ethanol concentrations, either through flex-fuel or E85 conversion kit. Both regulated and non-regulated emissions are characterized to highlight the fuel and vehicle technology impacts. The analysis of non-regulated pollutants in exhaust gases is performed with three different techniques to evaluate their advantages or limitations and assess time-resolved emission levels. HPLC coupled to UV detection to measure aldehydes and ketones. GC–MS was used for PAHs characterization. GC-FID was used to measure VOCs (C1 to C12) on the first phase of the WLTC. FTICR-MS was used to assess time-resolved emission levels. Results indicate a negligible impact on the emissions for ethanol content from 10 to 20% vol. Nevertheless, a significant emission composition variation is observed at 50% vol., and this is even more pronounced with 85% vol. of ethanol. Expected trends based on the literature review are confirmed for all vehicles and this includes an increase in unburned ethanol and aldehydes emissions with higher ethanol content while in this condition lower aromatics contribute to reduce particulate matters emissions. The use of varying amounts of ethanol in recent and diverse Euro 6d-temp vehicle technologies shows that the increase in ethanol content is unaffected by the reduction in particulate emissions and the increase in the finest. However, the results indicate a risk of increased NOx emissions for Euro 6d-temp IC engines, which should be confirmed on other vehicles of similar technology. This study results also indicate that most pollutants are emitted in the engine and exhaust warm-up phase. All analytical techniques exhibited similar trends. [ABSTRACT FROM AUTHOR]

Abstract: We present observations of plasma density structures crossed by the CLUSTER spacecraft constellation near orbit perigee, with the spacecraft located in the vicinity of the plasmapause boundary. Although the constellation is not arranged as a perfect tetrahedron, the four-point measurements reveal interesting properties of density structures, unknown before the four-points in situ observations from the CLUSTER mission. The set of plasma density profiles shown are derived from the EFW and WHISPER instruments observations in the dusk sector of the plasmasphere region. They yield new insights into: (i) comparative along and cross-field dimensions; (ii) the dynamics of small-scale structures. They illustrate the great opportunity offered by the CLUSTER mission to resolve new challenges in magnetospheric physics, including a clearer understanding of the physics involved in the dynamics of the plasmasphere and the formation of its outer boundary: the plasmapause. [Copyright &y& Elsevier]

Abstract: Irradiation by light is considered to be one of the primary sources of damage exerted upon cellulosic substrates at ambient conditions. Yet, contrary to studies on thermal ageing of cellulose, only limited attention is devoted to light induced degradation of paper. This research demonstrates that extensive oxidative degradation of cellulose, accompanied by formation of hydroxyl radicals, occurs during exposure to light with λ >340nm. As demonstrated by size exclusion chromatography, degradation is not random. No high-molecular weight fraction appears in the irradiated sample, meaning that cross-linking is not a dominant process. This justifies the use of viscometry for light-irradiated cellulosic materials. Studies show that the rate of degradation, carbonyl formation and brightness decrease may be reduced by addition of magnesium carbonate. [Copyright &y& Elsevier]