Cherenkov and Scintillation Light Separation in Organic Liquid Scintillators

The CHErenkov / Scintillation Separation experiment (CHESS) has been used to demonstrate the separation of Cherenkov and scintillation light in both linear alkylbenzene (LAB) and LAB with 2g/L of PPO as a fluor (LAB/PPO). This is the first such demonstration for the more challenging LAB/PPO cocktail and improves on previous results for LAB. A time resolution of 338 +/- 12 ps FWHM results in an efficiency for identifying Cherenkov photons in LAB/PPO of 70 +/- 3% and 63 +/- 8% for time- and charge-based separation, respectively, with scintillation contamination of 36 +/- 5% and 38 +/- 4%. LAB/PPO data is consistent with a rise time of 0.75 +/- 0.25 ns

Complex primary total hip arthroplasty

SummaryAlthough total hip arthroplasty is now a classic procedure that is well controlled by orthopedic surgeons, some cases remain complex. Difficulties may be due to co-morbidities: obesity, skin problems, muscular problems, a history of neurological disease or associated morphological bone deformities. Obese patients must be informed of their specific risks and a surgical approach must be used that obtains maximum exposure. Healing of incisions is not a particular problem, but adhesions must be assessed. Neurological diseases may require tenotomy and the use of implants that limit instability. Specific techniques or implants are necessary to respect hip biomechanics (offset, neck-shaft angle) in case of a large lever arm or coxa vara. In case of arthrodesis, before THA can be performed, the risk of infection must be specifically evaluated if the etiology is infection, and the strength of the gluteal muscles must be determined. Congenital hip dysplasia presents three problems: the position and coverage of the cup, placement of a specific or custom made femoral stem, with an osteotomy if necessary, and finally lowering the femoral head into the cup by freeing the soft tissues or a shortening osteotomy. Acetabular dysplasia should not be underestimated in the presence of significant bone defect (BD), and reconstruction with a bone graft can be proposed. Sequelae from acetabular fractures presents a problem of associated BD. Internal fixation hardware is rarely an obstacle but the surgical approach should take this into account. Treatment of acetabular protrusio should restore a normal center of rotation, and prevent recurrent progressive protrusion. The use of bone grafts and reinforcement rings are indispensible. Femoral deformities may be congenital or secondary to trauma or osteotomy. They must be evaluated to restore hip biomechanics that are as close to normal as possible. Fixation of implants should restore anteversion, length and the lever arm. Most problems that can make THA a difficult procedure may be anticipated with proper understanding of the case and thorough preoperative planning

Effects of electron-phonon interactions on the electron tunneling spectrum of PbS quantum dots

We present a tunnel spectroscopy study of single PbS Quantum Dots (QDs) as function of temperature and gate voltage. Three distinct signatures of strong electron-phonon coupling are observed in the Electron Tunneling Spectrum (ETS) of these QDs. In the shell-filling regime, the $8\times$ degeneracy of the electronic levels is lifted by the Coulomb interactions and allows the observation of phonon sub-bands that result from the emission of optical phonons. At low bias, a gap is observed in the ETS that cannot be closed with the gate voltage, which is a distinguishing feature of the Franck-Condon (FC) blockade. From the data, a Huang-Rhys factor in the range $S\sim 1.7 - 2.5$ is obtained. Finally, in the shell tunneling regime, the optical phonons appear in the inelastic ETS $d^2I/dV^2$.Comment: 5 pages, 5 figure

Inflammation and CFTR: might neutrophils be the key in cystic fibrosis?

The aim of this hypothesis is to provide new insights into the still unclear mechanisms governing airway inflammation in cystic fibrosis. Although the genetic basis of cystic fibrosis as well as the molecular structure of cystic fibrosis transmembrane regulator (CFTR), the mutated protein which causes the disease, have been well defined, a clear relationship between the genetic defect and the pulmonary pathophysiology, especially chronic infections and neutrophil-dominated airway inflammation has not been established. Cystic fibrosis is thus a unique pathological situation in that neutrophils can be depicted as both an antiinfectious and a proinflammatory cell. In cystic fibrosis there is an emerging picture of an imbalance between these two roles with both a reduction in the antiinfectious efficacy and an augmentation of the proinflammatory functions. Better knowledge of fundamental defects in neutrophil function in cystic fibrosis as well as a novel cellular function of CFTR, which will be reviewed, will allow identification of potentially new clinical targets and aid selective therapeutic action aimed at counteracting the lethal neutrophil-induced airway inflammation. The rationale for colchicine therapy is a significant example of a drug which might act both at the molecular levels on CFTR expression in epithelial cells and on neutrophils to mediate antiinflammatory effects. Preliminary results are presented in this issue (Med Inflamm 1999; 8: 13-15)

Is there something of the MCT in orientationally disordered crystals ?

Molecular Dynamics simulations have been performed on the orientationally disordered crystal chloroadamantane: a model system where dynamics are almost completely controlled by rotations. A critical temperature T_c = 225 K as predicted by the Mode Coupling Theory can be clearly determined both in the alpha and beta dynamical regimes. This investigation also shows the existence of a second remarkable dynamical crossover at the temperature T_x > T_c consistent with a previous NMR and MD study [1]. This allows us to confirm clearly the existence of a 'landscape-influenced' regime occurring in the temperature range [T_c-T_x] as recently proposed [2,3].Comment: 4 pages, 5 figures, REVTEX

Validation of an educational booklet targeted to patients candidate for total knee arthroplasty

SummaryBackgroundKnee osteoarthritis is a highly prevalent condition and the leading reason for total knee arthroplasty (TKA). No consensus exists about the optimal content of preoperative patient information and, to the best of our knowledge, no validated information document is available. Our objective here was to obtain validation by healthcare professionals and patients of an educational booklet for patients awaiting TKA.Materials and methodsThe booklet was developed and validated in six phases: systematic literature review, drafting of the first version, critical revision by a panel of experts, modification of the booklet, validation by a multidisciplinary panel of experts, and validation by two groups of patients, one composed of patients awaiting TKA and the other of patients in the immediate post-TKA period. We assessed the impact of the booklet based on knowledge and belief scores before and 2 days after receiving the booklet.ResultsCritical revision of the first draft led to changes to meet the concerns voiced by the experts. Knowledge improved only in the patient group given the booklet preoperatively (from 6/10 to 9/10, P=0.005). The booklet did not modify beliefs in either patient group.DiscussionWe used a rigorous methodology to develop and validate the contents of an educational booklet. Receiving this document before TKA resulted in improved patient knowledge but had no impact on beliefs.Level of evidenceLevel IV

Experimentations on the retrofitting of damaged Single Step Joints with Self-Tapping Screws

When assessing the roof of existing buildings, engineers may be confronted with structural joints badly preserved, for instance the damaged Single Step Joint (SSJ) located at the foot of timber trusses. Since the early appearance of failure modes in this traditional carpentry connection may lead to the collapse of the whole timber truss, the retrofitting of damaged SSJ is then required as an economically-viable intervention to stabilize the roof structure. In consequence, the retrofitting of damaged SSJ with Self-Tapping Screws (STS) has been conducted through the Experimental Campaign in order to explore further different possibilities offered by this recent intervention technique (Sobra et al. (2016)). To this end, two strategies, noted R1 and R2, have been proposed to retrofit the SSJ specimens with STS, which had been previously damaged due to both failure modes, namely the crushing at the front-notch surface and the shear crack in the tie beam (Verbist et al. (2017)). Afterwards, the SSJ specimens retrofitted with STS have been tested under monotonic compression in the rafter in order to pull out their mechanical behaviour encompassing the failure modes, the force-displacement response, the stiffness of the connection, and the ultimate normal force in the rafter. By comparing the mechanical behaviour of retrofitted SSJ specimens with the initial ones from Verbist et al. (2017), the performances of both retrofitting strategies with STS have been discussed. Furthermore, the impact of the shear row splitting on the mechanical behaviour of retrofitted SSJ has been evaluated, by providing some warnings to engineers when intervening in existing timber trusses featuring natural damage such as the shrinkage splitting.This work was financed by FEDER funds through the Competitively Factors Operational Programme - COMPETE and by national funds through FCT – Foundation for Science and Technology within the scope of the research projects INVISIBLE WOODS PTDC/EPH-PAT/2401/2014, PROTIMBER PTDC/ECM-EST/1072/2014, and the PhD Scholarships SFRH/BD/128580/2017.info:eu-repo/semantics/publishedVersio

Comparaison des résultats analytiques obtenus en émission de flamme et en absorption atomique

Ces dernières années, l'intérêt de l'analyse chimique par spectrophotométrie de flamme s'est accru considérablement. L'absorption atomique a également connu un essor notable et permet actuellement de doser la plupart des éléments du système périodique. On rend compte des progrès de la technique analytique dans ces domaines et l'on décrit avec précision les conditions de travail requises pour l'analyse des verres, en particulier pour le dosage de B2O3, AI2O3, CaO et BaO