Is E-FAST possible and useful on the battlefield? A feasibility study during medical courses in hostile environment (MEDICHOS): preliminary results.

INTRODUCTION: The extent of the French forces' territory in the Sahel band generates long medical evacuations. In case of many victims, to respect the golden hour rule, first-line sorting is essential. Through simulation situations, the aim of our study was to assess whether the use of ultrasound was useful to military doctors. METHODS: In combat-like exercise conditions, we provided trainees with a pocket-size ultrasound. Every patient for whom the trainees chose to perform ultrasound in role 1 was included. An extended focused assessment with sonography for trauma (E-FAST) was performed with six basic sonographic views. We evaluated whether these reference views were obtained or not. Once obtained by the trainees, pathological views corresponding to the scenario were shown to assess whether the trainees modified their therapeutic management strategy and their priorities. RESULTS: 168 patients were treated by 15 different trainee doctors. Of these 168 patients, ultrasound (E-FAST or point-of-care ultrasound) was performed on 44 (26%) of them. In 51% (n=20/39) of the situations, the practitioners considered that the realisation of ultrasound had a significant impact in terms of therapeutic and evacuation priorities. More specifically, it changed therapeutic decisions in 67% of time (n=26/39) and evacuation priorities in 72% of time (n=28/39). CONCLUSION: This original work showed that ultrasound on the battlefield was possible and useful. To confirm these results, ultrasound needs to be democratised and assessed in a real operational environment.

Can the number of surgery delays and postponements due to unavailable instrumentation be reduced? Evaluating the benefits of enhanced collaboration between the sterilization and orthopedic surgery units.

INTRODUCTION: The development of outpatient surgery, cost-reduction pressures and instrumentation storage limitations have led to their use "just-in-time". A recent study showed that stoppage of surgical procedures immediately before the incision (No-Go) was often due to the management of supplies and implantable medical devices. To our knowledge, since the development of outpatient surgery and the shortening of hospital stays, managing the flow of instrumentation has not been optimized. At our hospital, we used a two-prong approach consisting of a tool to manage instrumentation and working group from the sterilization and orthopedic surgery units. The aims of this study were to: 1) evaluate whether this approach led to better notification of the risk of supply shortage for instrumentation and 2) determine whether it could reduce by at least half operating room disruptions such as delays or cancellation of surgical procedures. HYPOTHESIS: This approach results in better notification of the risk of supply shortage for instrumentation and reduces by at least half operating room disruptions such as delays or cancellation of surgical procedures. MATERIAL AND METHODS: A tool was developed to manage instrumentation flow based on a retrospective analysis of data from 2015. This tool consisted of: (1) a list of instrumentation needed for each surgical procedure from an analysis of the surgical schedule and verification of traceability labels of the instrumentation actually used, (2) a list of reasons for supply shortage identified from an analysis of non-conformities occurring in the sterilization process of instrumentation kits. These analyses resulted in the development of checklists for instrument sets for each procedure, while identifying those with a high risk of shortage. In 2017, a working group focused on instrumentation was set up with personnel from the sterilization unit and the orthopedic surgery unit. Based on the check-lists and the schedule 24hours before the surgery, the sterilization unit alerted the surgery unit by email of the risk of material shortage; the surgery ward replied with potential changes to the material or the surgery planning. This approach (instrumentation management tool and working group) was named just-in-time (JIT). The main outcome was the number of notifications of potential supply shortage with and without JIT over a 10-week period. The secondary outcomes were the number of notifications resolved in time and the occurrence of operating room disruptions (delay>30min or postponement of surgery) related to unavailable instrumentation. RESULTS: Nine reasons for potential supply shortage were identified such as instrumentation kits used for several types of procedures, those with fast rotation and low stock, or in double pathways (on loan and on deposit). The working group reported 163 potential shortages with JIT versus 41 without (p<10-5), of which 150 (92.5%) were resolved. Thirteen operating room disruptions occurred; only one was not detected by the JIT approach. CONCLUSION: Our JIT approach (instrumentation management tool and working group) is effective at preventing instrumentation supply shortages. LEVEL OF EVIDENCE: III, prospective comparative study.

In situ structural analysis of calcium aluminosilicate glasses under high pressure.

In situ micro-Raman spectroscopy was used to investigate the structural evolution of OH(-)-free calcium aluminosilicate glasses, under high pressure and at room temperature. Evaluation was made of the role of the SiO2 concentration in percalcic join systems, for Al/(Al + Si) in the approximate range from 0.9 to 0.2. Under high pressure, the intensity of the main band related to the bending mode of bridging oxygen ([Formula: see text][T-O-T], where T = Si or Al) decreased gradually, suggesting that the bonds were severely altered or even destroyed. In Si-rich glasses, compression induced a transformation of Q (n) species to Q (n-1). In the case of Al-rich glass, the Al in the smallest Q (n) units evolved from tetrahedral to higher-coordinated Al (([5])Al and ([6])Al). Permanent structural changes were observed in samples recovered from the highest pressure of around 15 GPa and, particularly for Si-rich samples, the recovered structure showed an increase of three-membered rings in the Si/Al tetrahedral network.

Permanently densified SiO2 glasses: a structural approach.

Densified silica can be obtained by different pressure and temperature paths and for different stress conditions, hydrostatic or including shear. The density is usually the macroscopic parameter used to characterize the different compressed silica samples. The aim of our present study is to compare structural modifications for silica glass, densified from several routes. For this, densified silica glasses are prepared from cold and high temperature (up to 1020 °C) compressions. The different densified glasses obtained in our study are characterized by micro-Raman spectroscopy. Intertetrahedral angles from the main band relative to the bending mode decrease and their values are larger for densified samples from high temperature compression than those samples from cold compression. The relative amount of 3-membered rings deduced from the D2 line area increases as a function of density for cold compression. The temperature increase during the compression process induces a decrease of the 3 fold ring population. Moreover, 3 fold rings are more deformed and stressed for densified samples at room temperature at the expense of those densified at high temperature. Temperature plays a main role in the reorganization structure during the densification and leads to obtaining a more relaxed structure with lower stresses than glasses densified from cold compression. The role of hydrostatic or non-hydrostatic applied stresses on the glass structure is discussed. From the Sen and Thorpe central force model, intertetrahedral angle average value and their distribution are estimated.

Elastic moduli of permanently densified silica glasses.

Modelling the mechanical response of silica glass is still challenging, due to the lack of knowledge concerning the elastic properties of intermediate states of densification. An extensive Brillouin Light Scattering study on permanently densified silica glasses after cold compression in diamond anvil cell has been carried out, in order to deduce the elastic properties of such glasses and to provide new insights concerning the densification process. From sound velocity measurements, we derive phenomenological laws linking the elastic moduli of silica glass as a function of its densification ratio. The found elastic moduli are in excellent agreement with the sparse data extracted from literature, and we show that they do not depend on the thermodynamic path taken during densification (room temperature or heating). We also demonstrate that the longitudinal sound velocity exhibits an anomalous behavior, displaying a minimum for a densification ratio of 5%, and highlight the fact that this anomaly has to be distinguished from the compressibility anomaly of a-SiO2 in the elastic domain.

In situ Brillouin study of sodium alumino silicate glasses under pressure.

The in situ elastic and plastic behaviors of sodium aluminosilicate glasses with different degrees of depolymerization were analyzed using Brillouin spectroscopy. The observed elastic anomaly progressively vanished with depolymerization. The densification process appears to be different from that observed in pure silica glass. In the plastic regime of densified glasses hysteresis loops were observed and related to modification of the local silicon environment facilitated by the addition of sodium.

Permanent densification of compressed silica glass: a Raman-density calibration curve.

Raman scattering experiments have been carried out to study persistent densification in SiO(2) glass following hydrostatic compression at room temperature. A new relationship linking selective Raman parameters to the degree of densification in the glass has been developed here. This approach will allow quantification of the residual densification in silica following microindentation experiments, with the goal being the development of a constitutive law for amorphous silica.

Hysteretically reversible phase transition in a molecular glass.

Pressure induced densification in a molecular arsenic sulfide glass is studied at ambient temperature using x-ray scattering, absorption and Raman spectroscopic techniques in situ in a diamond anvil cell. The relatively abrupt changes in the position of the first sharp diffraction peak, FSDP, and the pressure-volume equation of state near ∼2 GPa suggest a phase transition between low- and high-density amorphous phases characterized by different densification mechanisms and rates. Raman spectroscopic results provide clear evidence that the phase transition corresponds to a topological transformation between a low-density molecular structure and a high-density network structure via opening of the constituent As(4)S(3) cage molecules and bond switching. Pressure induced mode softening of the high density phase suggests a low dimensional nature of the network. The phase transformation is hysteretically reversible, and therefore, reminiscent of a first-order phase transition.

Progressive transformations of silica glass upon densification.

The elastic and plastic behaviors of silica glasses densified at various maximum pressure reached (12 GPa, 15 GPa, 19 GPa, and 22 GPa), were analyzed using in situ Raman and Brillouin spectroscopies. The elastic anomaly was observed to progressively vanish up to a maximum pressure reached of 12 GPa, beyond which it is completely suppressed. Above the elastic anomaly the mechanical behavior of silica glass, as derived from Brillouin measurements, is interpreted in terms of pressure induced transformation of low density amorphous silica into high density amorphous silica.

Quantum cutting in CaYAlO4: Pr3+, Yb3+.

The deposition of a thin layer of a quantum-cutter material on top of silicon-based solar cells seems to be a promising solution to reduce the thermalization losses. This mechanism has been reported in materials codoped with Pr3+-Yb3+, where Pr3+ can sensitize two Yb3+ ions for one absorbed blue photon. In the present Letter, we analyze precisely energy transfers between Pr3+ and Yb3+ in CaYAlO4, and we measure a quantum-cutting rate of 145%. We show that a very efficient back transfer from Yb3+ toward the (1)G4 level of Pr3+ ion leads to a strong reduction of the quantum yield.

Correlation between boson peak and anomalous elastic behavior in GeO2 glass: an in situ Raman scattering study under high-pressure.

We present low-frequency Raman scattering of pure GeO(2) glass under pressure up to 4 GPa, corresponding to an elastic transformation. Intensity variation and frequency shift of the boson peak are analysed and compared to the Debye model. The decrease of the boson peak intensity scaled by the Debye energy is correlated to the elastic anomalous properties under pressure up to 1.5 GPa, and interpreted as an elastic homogenisation process at the local scale. We emphasize similarities between a-GeO(2) and a-SiO(2) behavior under pressure, and compare our results to other experiments, numerical studies, and predictions of several models concerning amorphous systems.

Soda-lime silicate glass under hydrostatic pressure and indentation: a micro-Raman study.

Raman micro-spectroscopy is used to analyse the plastic behaviour of window glass (a soda-lime silicate glass) under high hydrostatic pressure and Vickers indentation. We show pressure-induced irreversible structural changes, notably an increase of Q(2) species at the expense of Q(3). For the first time, a very accurate [Formula: see text] calibration curve has been established. Local density variations of a Vickers indented window glass have been characterized by micro-Raman mapping using a high spatial resolution device. The effects of glass depolymerization on indentation and hydrostatic compression are discussed. Differences between window glass and pure SiO(2) glass behaviour under high stresses are also highlighted and analysed at a local scale.

In situ Raman spectroscopy of pressure-induced changes in LaBGeO(5) glass: hysteresis and plastic deformation.

In situ micro-Raman spectroscopy was performed on lanthanum borogermanate (LBG) glasses, compressed in a diamond anvil cell at ambient temperature. Up to 5.6 GPa the structural changes are reversible, whereas experiments performed at 10 GPa and higher are characterized by hysteresis loops. A noticeable change of evolution of the main Raman band at 800 cm(-1) has been evidenced around 8 GPa. Indeed, at such a pressure, this Raman band is shifted in the opposite direction while the pressure is still increasing. This change of slopes may be the sign of a pressure-induced coordination number change. Upon decompression the Raman shift of this band follows a different path from the one during compression. When the sample is returned to ambient pressure, it shows a shifted and lightly modified Raman spectrum, suggesting that a new amorphous phase for LBG glass is reached under high pressure and still exists at atmospheric pressure. However, a comparison with LaBGeO(5) crystals with the same composition shows that this material has a full elastic behaviour in the same pressure range.

Results from a four-year study on the prevalence of nosocomial infections in Franche-Comté: attempt to rank the risk of nosocomial infection.

The aim of this study was to rank the risk of nosocomial infection (NI) according to patient type by analysing the results of annual prevalence studies carried out in Franche-Comté from 2001 to 2004. Patients (N=14,905) were divided into four categories according to the number of endogenous risk factors (age, immunodepression, MacCabe score). The overall prevalence of infection was 6.1% and varied according to the category of patient from 1.93% (no risk factors) to 15.2% (three risk factors). The frequencies of NI related to an invasive procedure and to cross-contamination with multi-drug-resistant (MDR) bacteria were 30.9% and 12.3%, respectively; these percentages did not depend on the type of patient. The prevalence of NI decreased over time for patients with two or three risk factors, but was stable for patients with no risk factors. More than 40% of NIs were potentially avoidable (related to invasive procedures or involving cross-transmission of an MDR bacterium) regardless of the category of patient. This study suggests that at least 30% of NIs could be avoided.

[Muir-Torre syndrome and familial colorectal cancer: 2 families with molecular genetic analysis]. / Syndrome de Muir-Torre et cancer colorectal familial: deux familles avec étude génétique moléculaire.

INTRODUCTION: The Muir-Torre Syndrome is a rare genodermatosis, defined by the occurrence of cutaneous tumors (such as sebaceous adenomas, epitheliomas, or carcinomas, and/or keratoacanthomas), and internal malignancies. Recently, molecular analysis in hereditary non polyposis colorectal cancer demonstrated a common genetic basis, linking these two disorders, with the observation of germline mutations in the hMSH2 gene (one of the DNA mismatch repair system genes) in both syndromes. Such molecular demonstration of a single nosological entity should be clinically used to improve the indications of molecular testings in oncogenetics, still restricted to highly stringent criteria for hereditary non polyposis colorectal cancer. CLINICAL CASES: We identified three patients from two different families, who fulfilled the criteria for both Muir-Torre Syndrome and hereditary non polyposis colorectal cancer. The search of a germline mutation of the hMSH2 gene was performed on an affected member from each family, and their relatives with their informed consent. Within each family, all individuals with colorectal cancer were carriers of the same mutation. In the first family, this mutation was a pathogenic microinsertion, usable for predictive testing. In the second family, a missense mutation was identified, requesting further demonstration of its pathogenicity before its use in a predictive purpose. CONCLUSIONS: The diagnosis of cutaneous tumors compatible with Muir-Torre syndrome should lead the dermatologist to suspect an hereditary non polyposis colorectal cancer that should bring to an oncogenetic approach: personnal and familial history of colorectal cancer, molecular analysis, recommendations for colonoscopic screening in at-risk relatives. In the case of a colorectal cancer at a young age, or in the case of familial cases, the gastroenterologist should screen for cutaneous lesions of Muir-Torre syndrome, which could add a criteria for an hereditary syndrome, and lead to molecular oncogenetic analysis.