Cementless, modular, titanium stem in Vancouver B2 and B3 periprosthetic femoral fractures.

INTRODUCTION: The periprosthetic femoral fracture (PFF) is a serious complication after primary total hip arthroplasty. We conducted a retrospective study to determine whether the PRIUS® system presented similar survival to other existing implants for the treatment of Vancouver B2 or B3 PFFs. Bone consolidation rate, functional results and complications were analysed. METHOD: This is a bi-centric retrospective study between 2012 and 2017 including 39 patients with (B2/B3) PFFs treated by senior surgeons using a PRIUS® femoral implant. Implant survival, radiological outcome (fracture healing) and clinical scores (Oxford-OHS, Harris Hip Score-HHS, Postel Merle d'Aubigné-PMA, Devane and Charnley) were analysed. 10 patients had died before data collection and 5 patients were lost to follow-up. A total of 21 patients were able to undergo a clinical and radiological evaluation. The mean follow-up period was 3 years. RESULTS: The 3-year PRIUS® stem survival rate was 88.6% [95% CI, 77.2-100]. The consolidation rate was 81% (17/21). The rate of satisfied or very satisfied patients was 85.6% (18/21). Regarding the Devane score, activity level was maintained in 70.6% of cases (12/17) and decreased in 29.4% of cases (5/17), the Charnley score was stable in 94% of cases (16/17) and decreased in 6% of cases (1/17). The mean Oxford score was 28.8/48 (9.3; 16-48), the mean HHS was 67/100 (16.4; 46-91) and the mean PMA score was 12.6/18 (4.5; 2-18). CONCLUSION: The results in terms of survival rate and bone consolidation are comparable to other literature series. The PRIUS® System can be added to the surgical arsenal in the treatment of (B2/B3) PFF, subject to confirmation of these results in the longer term.

Measurement of radon, thoron and their daughters in the air of marble factories and resulting alpha-radiation doses to the lung of workers.

Concentrations of radon (222Rn) and thoron (220Rn) were measured in the air of different marble factories by using a nuclear track technique. The influence of the marble dust nature and ventilation on radon and thoron concentrations was investigated. It was observed that measured radon and thoron concentration ranged from 310 to 903 Bq m-3 and 6 to 48 Bq m-3, respectively. In addition, alpha-activities due to the unattached and attached fractions of 218Po and 214Po radon short-lived progeny were evaluated in the marble factories studied. Committed equivalent doses due to the attached and unattached fractions of 218Po and 214Po nuclei were evaluated in the lung tissues of marble factory workers. The dependence of the resulting committed equivalent dose on the concentration of the attached and unattached fractions of the 218Po and 214Po radionuclides and mass of the tissue was investigated. The resulting annual committed effective doses to the lung of marble factory workers due to the attached and unattached fractions of the 218Po and 214Po radionuclides were calculated. The obtained results show that about 80% of the global committed effective doses received by workers in the studied marble factories are due to the attached fraction of the 218Po and 214Po radon short-lived daughters from the inhalation of polluted air. Male workers spending 8 h per day (2080 h per year) in a marble factory receive a maximum dose of 34.46 mSv y-1 which is higher than the (3-10 mSv y-1) dose limit interval given by the ICRP. Good agreement was found between data obtained for the average effective dose gotten by using this method and the UNSCEAR and ICRP conversion dose coefficients.

Establishment of beam qualities for medical applications (mammography and CT) in the gamma and X calibration laboratory of CNESTEN according to EN 61267 standards.

The present study aimed to validate the different radiodiagnostic beam qualities (RQT, WAH and WAV) by the measurements of the X-ray beams HVL of a HOPEWELL generator, X80-225 kV from a high voltage range of 10 at 200 kV, at CNESTEN Gamma and X Calibration Laboratory. The experiments were carried out using the PTW TN 32005 ionization chamber, established at 100 cm from the center of the X-ray tube and connected to a SUPERMAX electrometer. The HVL values were measured by applying the attenuation law to the flow of Kair air kerma, including their uncertainties. The obtained HVL values were compared with standard values of diagnostic levels. It was observed that the HVL of the present X-ray machine in most qualities are smaller than the standard ones. An approved method (described in the STANDARD EN 61267 and IAEA TECHNICAL REPORTS SERIES n° 457) was applied to determine the amount of additional filtration required to meet the standard values, and by checking their compliance with the maximum absolute deviation. The results indicate the adequacy of the LEGX laboratory for the calibration of the radiation detection instruments used in computed tomography and mammography with an expanded uncertainty in the best measurement capability of ±4 % (k = 2).

Study of Alpha and Beta Radioactivity of Clay Originating from Radionuclides Belonging to the 238U and 232Th Families: Doses to the Skin of Potters.

ABSTRACT: Pottery objects are presently more and more used for decoration in homes and hotels. To assess radiological hazards to potters, 238U, 232Th, 222Rn, and 220Rn radionuclides were analyzed in different clay body samples used for pottery production by means of CR-39 and LR-115 II track detectors. Data obtained were compared to those gotten by means of isotope dilution mass spectrometry. Annual equivalent doses to the skin of potters resulting from the energy loss of alpha-particles emitted by the radionuclides of the 238U and 232Th radioactive families were evaluated. Estimates of the annual equivalent doses to the skin of potters due to the emitted alpha-particles ranged between 6.45 mSy y-1 cm-2 and 17.50 mSy y-1 cm-2 and between 1.87 mSy y-1 cm-2 and 5.33 mSy y-1 cm-2, respectively. Annual equivalent doses received by the skin of potters due to beta-particles (ß-) emitted by the radionuclides of the 238U and 232Th series inside the studied clay body samples were determined. Alpha equivalent doses to the skin of potters resulting from the diffusion of 222Rn and 220Rn gases present in the studied clay body samples were calculated. A total maximum annual equivalent dose of 23.0 mSv y-1 cm-2, resulting from the energy loss of alpha and beta minus particles emitted by the radionuclides of the 238U and 232Th series, was found for potters working 8 h d-1(6 d wk-1, 49.28 wk y-1).

Surface acoustic waves in one-dimensional piezoelectric-metallic phononic crystal: Effect of a cap layer.

We study the propagation of transverse acoustic waves associated with the surface of a semi-infinite superlattice (SL) composed of piezoelectric-metallic layers and capped with a piezoelectric layer. We present closed-form expressions for localized surface waves, the so-called Bleustein-Gulyaev (BG) waves depending on whether the cap layer is open-circuited or short-circuited. These expressions are obtained by means of the Green's function method which enables to deduce also the densities of states. These theoretical results are illustrated by a few numerical applications to SLs made of piezoelectric layers of hexagonal symmetry belonging to the 6 mm class such as PZT4 and ZnO in contact with metallic layers such as Fe, Al, Au, Cu and boron-doped-diamond. We demonstrate a rule about the existence of surface modes when considering two complementary semi-infinite SLs obtained by the cleavage of an infinite SL along a plane parallel to the piezoelectric layers. Indeed, when the surface layers are open-circuited, one obtains one surface mode per gap, this mode is associated with one of the two complementary SLs. However, when the surface layers are short-circuited, this rule is not fulfilled and one can obtain zero, one or two modes inside each gap of the two complementary SLs depending on the position of the plane where the cleavage is produced. We show that in addition to the BG surface waves localized at the surface of the cap layer, there may exist true guided waves and pseudo-guided waves (i.e. leaky waves) induced by the cap layer either inside the gaps or inside the bands of the SL respectively. Also, we highlight the possibility of existence of interface modes between the SL and a cap layer as well as an interaction between these modes and the BG surface mode when both modes fall in the same band gaps of the SL. The strength of the interaction depends on the width of the cap layer. Finally, we show that the electromechanical coupling coefficient (ECC) is very sensitive to the cap layer thickness, in particular we calculate and discuss the behavior of the ECC as a function of the adlayer thickness for the low velocity surface modes of the SL which exhibit the highest ECC values. The effect of the nature of the metallic layers inside the SL on the ECC is also investigated. The different surface modes discussed in this work should have applications in sensing applications.

Subsurface transfer of chloride after a lake retreat in the central Andes.

The area under study covers 3500 km2 in the upstream part of the closed catchment basin of the salt crust of Uyuni. This crust is a remnant of the saline Lake Tauca, which covered the area about 15,000 years ago. In the downstream part of the aquifer, the Cl concentration of ground water and Cl content in the unsaturated zone exceed 20 meq/L and 18 kg/m2, respectively. With the present hydrological conditions under semiarid conditions, the ground water residence time in the study area exceeds 3000 years. Transient simulations over 11,000 years were made using initial conditions as the retreat of Lake Tauca and taking into account a low recharge during the arid mid-Holocene period. The modeling simulates ground water flow, Cl transport, and ground water residence time. It includes the evaporation from the aquifer that leads to the accumulation of chloride in the unsaturated zone. Results of the modeling are consistent with the observations if it is assumed that the Cl previously accumulated in the unsaturated zone was flushed back into the aquifer around 2000 years B.P., contemporaneously with the end of the arid period.

Electromagnetically induced absorption in detuned stub waveguides: a simple analytical and experimental model.

We give an analytical and experimental demonstration of a classical analogue of the electromagnetic induced absorption (EIA) in a simple photonic device consisting of two stubs of lengths d1 and d2 grafted at the same site along a waveguide. By detuning the lengths of the two stubs (i.e. δ = d(2) - d(1)) we show that: (i) the amplitudes of the electromagnetic waves in the two stubs can be written following the two resonators model where each stub plays the role of a radiative resonator with low Q factor. The destructive interference between the waves in the two stubs may give rise to a sharp resonance peak with high Q factor in the transmission as well as in the absorption. (ii) The transmission coefficient around the resonance induced by the stubs can be written following a Fano-like form. In particular, we give an explicit expression of the position, width and Fano parameter of the resonances as a function of δ. (iii) By taking into account the loss in the waveguides, we show that at the transmission resonance, the transmission (reflection) increases (decreases) as a function of δ. Whereas the absorption goes through a maximum around 0.5 for a threshold value δth which depends on the attenuation in the system and then falls to zero. (iv) We give a comparison between the phase of the determinant of the scattering matrix, the so-called Friedel phase and the phase of the transmission amplitude. (v) The effect of the boundary conditions at the end of the resonators on the EIA resonance is also discussed. The analytical results are obtained by means of the Green's function method, whereas the experiments are carried out using coaxial cables in the radio-frequency regime. These results should have important consequences for designing integrated devices such as narrow-frequency optical or microwave filters and high-speed switches.

Early surgical site infection in adult appendicular skeleton trauma surgery: a multicenter prospective series.

INTRODUCTION: Surgical site infections (SSI) studies rely on an imprecise and debatable definition. The term "wound healing problems" (WHP), not necessarily septic, is also frequently cited. This study had the objectives of determining the frequency of early SSIs in traumatology, these terms eventual correlation, and the factors influencing onset. PATIENTS AND METHODS: A multicenter prospective observational study was conducted in 12 centers. The exclusion criteria were open lesions as well as multiple injuries and multiple fractures (more than two fractures treated surgically). All patients were followed for the first three postoperative months until there was clinical certainty of healing and absence of infection. The presence of any WHP or SSI required a minimum follow-up of 1 year. WHP and SSI risk factors were determined using logistical regression adjusted on the centers. RESULTS: Out of 1617 cases, 103 were complicated by a WHP and 22 by a SSI. The SSIs were mainly secondary to Staphylococcus infections. The factors predisposing the patients to WHP and SSI (p≤0.05) were age; the NNIS, ASA, and Parker scores; alcoholism; antiaggregant use; and the locoregional aspect at the time of injury. The 522 subcutaneous osteosyntheses "near the skin" resulted in 58 WHPs (11%) and 14 SSIs (2.7%); 13 of the 58 WHPs (22%) resulted in one SSI. Out of 707 deep osteosyntheses, 24 (3.4%) presented a WHP and seven (1%) a SSI; Four SSIs originated from a WHP. The 352 fractures of the trochanter were complicated by a WHP in 15 cases (5.5%) and a SSI in one case (0.4%) after interlocked nailing and two WHPs and two SSIs (2.5%) after screw and plate fixation. Of the 388 first-line arthroplasties, only the prostheses implanted for a proximal femur fracture presented complications: 21 WHPs (6%) and one SSI (0.02%). Of the 103 WHPs of the entire series, 18 became SSIs. In absence of WHP, the SSI rate was 0.2%, whereas the probability of a WHP evolving toward a SSI was 100 times higher. The only factor significantly associated with a WHP becoming a SSI was osteosynthesis material exposure. DISCUSSION: This prospective study can be criticized on several points: the deliberately limited inclusion criteria, the short follow-up, and the possible subjectivity of the data collection. The SSI rates reported are for the most part in agreement with the literature. This study is innovative in traumatology given the large number of patients and the notion of WHP that was preferred over superficial infection. It demonstrates the relations between WHP and SSI, in particular for osteosyntheses near the skin. LEVEL OF EVIDENCE: Level III.

[Epidemiology of patients harboring extended-spectrum beta-lactamase-producing enterobacteriaceae (ESBLE), on admission]. / Épidémiologie des patients porteurs d'entérobactéries sécrétrices de bêtalactamase à spectre élargi (EBLSE), à l'admission.

OBJECTIVE: The incidence of extended-spectrum beta-lactamase-producing enterobacteria (ESBLE) has regularly increased over the last few years. However, little is known about epidemiology of ESBLE carriers in France. The objective of this study was to determine the ESBLE carriers or infected patients profile, identified within 48 hours following hospital admission. DESIGN: This retrospective study included all patients admitted in 2006 and 2007 at the Necker-Enfants-Malades (NEM) teaching hospital, carrying or infected with ESBLE isolated within 48 hours following admission. The pediatric and adult populations were compared. RESULTS: There was no significant difference between pediatric and adult populations. Escherichia coli and Klebsiella pneumoniae were the two main species isolated, accounting respectively for 59.6 and 21.1 % of the 114 isolated strains. Among the 114 analyzed files, 24 patients (21 %) were known to be EBLSE carriers, 37 (32 %) were transferred from another hospital, including 16 from another country. Concerning the 54 (47 %) other patients, five (4 %) came from a country with high prevalence, and 44 (39 %) were treated for a chronic illness. Only five patients (4 %) carrying ESBLE did not have any usual risk factor for multidrug resistance (MDR) bacterial carriage. CONCLUSIONS: In our study, 4 % of patients carrying ESBLE admitted had no usual risk factor for MDR bacteria. Targeted screening of previous carriers, patients with chronic illness, transferred patients, or patients coming from country with high prevalence, would help to limit the spread of ESBLE.

High frequency SAW devices based on third harmonic generation.

We demonstrate the third harmonic generation in a ZnO/Si layered structure to obtain high frequency SAW devices. This configuration eliminates the need of high lithography resolution and allows easy integration of such devices and electronics on the same wafer. A theoretical study was carried out for the determination of the phase velocity and the electromechanical coupling coefficient (K(2)) dispersion curves of the surface acoustic waves. These results are also in agreement with those measured on a SAW filter designed for the third harmonic generation and the operating frequency is up to 2468 MHz.