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In various situations, targets with different characteristic dimensions are being exposed to blast waves generated by high explosive detonation. One of the existing mitigation methods consists of protecting the target from the explosion with a sandwiched crushable core between a front plate and the target. The pressure generated by the explosion is converted into the planar displacement of the front plate, which compresses the crushable core, delaying the transmission of the load to the target. The influence of the crushable core on the transmitted load in the form of a plateau stress is well described in the literature contrary to its influence on the transferred momentum. In this paper, momentum transmission during the crushing of the core has been experimentally investigated, taking into account the fluid–structure interaction effect, the mechanical behavior of the core, and the pneumatic effects generated by the air trapped into its cells. It is shown that the beneficial effects of fluid–structure interactions are often counterbalanced by the mechanical behavior of the core and that analytical models from the literature are sufficient to describe the order of magnitude of the uniaxial crushing process. [ABSTRACT FROM AUTHOR]

L'hallucination acoustico-verbale (HAV) présente un taux de prévalence de 12 % chez les enfants et les adolescents. Elle est considérée comme un phénomène développemental transitoire et bénin. Sa persistance à l'adolescence peut être associée à des diagnostics psychiatriques plus sévères. Le trouble de stress post traumatique (TSPT) est défini par des souvenirs traumatiques intrusifs répétitifs associés à des symptômes de reviviscences sensorielles (flashbacks). Bien que l'hallucination ne soit pas décrite comme un symptôme du TSPT, la littérature rapporte un risque de développer des HAV plus important chez les personnes présentant un TSPT. La clinique des hallucinations associées à un TSPT est un sujet d'étude. Nous proposons d'étudier les mécanismes en jeu dans le développement et l'évolution des HAV dans le cadre d'un TSPT en population pédiatrique. Quatre cas cliniques sont présentés afin d'illustrer ce sujet à partir d'enfants et d'adolescents présentant un diagnostic de TSPT (DSM 5) associé à des HAV sans trouble du spectre de la schizophrénie (DSM 5) associé. Les HAV présentées par nos patients peuvent être associées à des reviviscences traumatiques mais aussi à d'autres types d'hallucinations plus élaborées. Elles représentent plusieurs voix malveillantes au contenu négatif. Des liens thématiques et émotionnels peuvent être établis entre ces hallucinations et les traumatismes en question. Ils permettraient de comprendre l'hallucination comme une « ré-expérience » indirecte du traumatisme. Nous proposons un modèle de continuum de symptômes entre la reviviscence sensorielle et l'hallucination dont le risque futur est la constitution progressive vers un trouble psychotique. Le repérage de l'hallucination dans la population pédiatrique est un enjeu majeur pour le clinicien. L'hallucination est une expérience considérée à tort comme appartenant au trouble du spectre de la schizophrénie et ne suffit pas à retenir ce diagnostic. Auditory-verbal hallucination (AVH) has a prevalence rate of 12 % in children and adolescents. It is considered to be a transient and benign developmental phenomenon. Its persistence into adolescence may be associated with more severe psychiatric diagnoses. Post-traumatic stress disorder (PTSD) is defined by repetitive intrusive traumatic memories associated with symptoms of sensory reliving (flashbacks). Although hallucination is not described as a symptom of PTSD, the literature reports a greater risk of developing AVH in individuals with PTSD. The clinical aspect of hallucinations associated with PTSD is a topic of study. We propose to study the mechanisms involved in the development and evolution of AVH in the context of PTSD in a pediatric population. Four clinical cases are presented to illustrate this topic from children and adolescents with a diagnosis of PTSP (DSM 5) associated with AVH without associated schizophrenia spectrum disorder (DSM 5). The AVH presented by our patients can be associated with traumatic reliving but also with other types of more elaborate hallucinations. They represent several malevolent voices with negative content. Thematic and emotional links can be established between these hallucinations and the traumas in question. They allow us to understand the hallucination as an indirect "re-experience" of the trauma. We propose a model of a continuum of symptoms between sensory re-experiencing and hallucination whose future risk is the progressive constitution towards a psychotic disorder. The identification of the hallucination in the pediatric population is a major challenge for the clinician. Hallucination is an experience wrongly considered as belonging to the schizophrenia spectrum disorder and is not sufficient to retain this diagnosis. [ABSTRACT FROM AUTHOR]

The sandwich cladding is a blast mitigation technique well described in the literature. One of the key parameters for its efficiency is a good knowledge on the crushable core placed inside the cladding. This paper focuses on galvanised polyurethane foams, a new family of hybrid materials which can fill the role of a crushable core. The galvanisation process allows to add a metal layer on top of a polyurethane foam, modifying its behaviour under tension and compression. This material was subjected to quasi-static tests and then placed inside a sandwich cladding allowing its dynamic characterisation under blast load. Using the methodology recommended by previous work, the energy absorption capacity of this new material has been determined based on the measured experimental stress–strain curves. The parameters of these curves, such as the plateau stress, densification strain, and energy absorption by unit volume, are directly linked to several parameters of the galvanisation process, including the Cu/Ni composite coating as well as the coating thickness. The results of this study present galvanised polyurethane foams as a serious alternative for crushable cores, which can be tailor-made to protect different targets by changing the parameters of the galvanisation process. [ABSTRACT FROM AUTHOR]

This paper investigates a simple numerical method, based on the release of a pressurized spherical air volume, to predict or reproduce the main characteristics of the blast environment from the detonation of solid or gaseous charges. This approach aims to give an alternative to the use of a steady-state detonation model and a Jones-Wilkins-Lee equation of state to describe the expansion of the detonation products, especially when the explosive parameters are unknown and a TNT equivalent is used. The validity of the proposed approach is assessed through the comparison of predicted overpressure and impulse at different distances from the explosion with that of TNT and stoichiometric propane-oxygen explosions. It is also shown that, for gaseous detonations, a better agreement is obtained with the rationally optimized compressed balloon than with the use of a Jones-Wilkins-Lee model and a TNT equivalent mass. [ABSTRACT FROM AUTHOR]

This work deals with the design of a highly sensitive whole cell-based biosensor for heavy metal detection in liquid medium. The biosensor is constituted of a Love wave sensor coated with a polyelectrolyte multilayer (PEM). Escherichia coli bacteria are used as bioreceptors as their viscoelastic properties are influenced by toxic heavy metals. The acoustic sensor is constituted of a quartz substrate with interdigitated transducers and a SiO2 guiding layer. However, SiO2 shows some degradation when used in a saline medium. Mesoporous TiO2 presents good mechanical and chemical stability and offers a high active surface area. Then, the addition of a thin titania layer dip-coated onto the acoustic path of the sensor is proposed to overcome the silica degradation and to improve the mass effect sensitivity of the acoustic device. PEM and bacteria deposition, and heavy metal influence, are real time monitored through the resonance frequency variations of the acoustic device. The first polyelectrolyte layer is inserted through the titania mesoporosity, favouring rigid link of the PEM on the sensor and improving the device sensitivity. Also, the mesoporosity of surface increases the specific surface area which can be occupied and favors the formation of homogeneous PEM. It was found a frequency shift near −20±1kHz for bacteria immobilization with titania film instead of −7±3kHz with bare silica surface. The sensitivity is highlighted towards cadmium detection. Moreover, in this paper, particular attention is given to the immobilization of bacteria and to biosensor lifetime. Atomic Force Microscopy characterizations of the biosurface have been done for several weeks. They showed significant morphological differences depending on the bacterial life time. We noticed that the lifetime of the biosensor is longer in the case of using a mesoporous TiO2 layer. [ABSTRACT FROM AUTHOR]

Abstract: This work presents the design and the thermal behavior characterization of an innovative self-test portable surface acoustic wave platform for chemical detection under high temperature. Before the forthcoming deposition of the sensitive coating, the thermal behavior of the bare LGS acoustic platform has been focused on. The system includes a (0°, 140°, 25°) crystallographic cut langasite (LGS) piezoelectric substrate, a ceramic heater, and a platform with RF connections for remote measurements. The packaging consists in a hermetic stainless steel cell, which enables safe gas detection. Its thermal behavior was successfully investigated in the temperature range 25–500°C thanks to the integrated heater, without using an external furnace. Finite element modeling aided the development of this platform structure by predicting the thermal behavior of each of its parts and their cross-influences. The structure of the platform was specifically designed so that 500°C could be reached on the LGS acoustic device while the temperature on the PCB connections should not exceed 50°C. Then, the temperature-dependence on the waves generated by the acoustic transducers has been investigated through numerical modeling by resolving the wave propagation equations with several sets of LGS constants. Corresponding simulations showed good agreement with experiments, Thermal cycling up to 350°C highlighted satisfactory hardiness and response-reproducibility of the system towards thermal stress, after a first burn effect. [Copyright &y& Elsevier]

Abstract: A numerical treatment of fretting-wear under vibratory loading is proposed. The method is based on the Dynamic Lagrangian Frequency Time method. It models unilateral contact by using Coulomb’s friction law. The basic idea is to separate time into two scales, a slow scale for tribological phenomena and a fast scale for dynamics. For a given number of vibration periods, a steady state is assumed and the variables are decomposed into Fourier series. An Alternating Frequency Time procedure is performed to calculate the non-linear forces. Then, a hybrid Powell solver is used. Numerical investigations on a beam with friction contact interfaces illustrate the performances of this method and show the coupling between dynamic and tribological phenomena. [Copyright &y& Elsevier]

The relative influence of temperature versus local physical factors on the spatial distribution of riverine fish species was investigated in a large watershed of south-western France. Using generalised additive models and hierarchical partitioning, we modelled the ecological responses of 28 fish species to a set of five environmental predictors, and we quantified the independent effect of each predictor. The spatial distribution of fish species was primarily determined by both mean temperature and position along the upstream–downstream gradient. However, responses to these environmental factors varied according to the species considered. Fish species with strong thermal requirements (e.g., common carp, black bullhead, Atlantic salmon) were mainly sensitive to temperature whereas longitudinal gradient was of primary importance for downstream species (e.g., common bream, largemouth bass, pike perch). Both the statistical methods used gave concordant results and appeared complementary. This dual-approach, quantifying the relative contribution of each environmental factor, appears particularly useful to understand the spatial distribution of stream fish species. Separating the effects of temperature versus habitat factors is crucial to accurately predict species distribution modifications in the current context of global change. [ABSTRACT FROM AUTHOR]

A new approach, called the “Variational Theory of Complex Rays”, is being developed for the calculation of the vibrations of slightly damped elastic plates in the medium-frequency range. In this approach, the resolution of a small system of equations which does not result from a refined spatial discretization of the structure leads to the evaluation of effective quantities (deformation energy, vibration amplitude,…). This theory has already been validated for assemblies of homogeneous substructures and extended to the case of heterogeneous substructures. In this paper, we propose some improvements to deal with sensitivity analysis. The objective is to evaluate the influence of discontinuities with uncertain positions, sizes or directions on the structural response. A specific partial inversion of the constrained system of equations enables multiple resolutions for combinations of the parameters defining the possible shapes of the discontinuity to be carried out at low cost. [Copyright &y& Elsevier]

Objective: Continuous renal replacement therapy (CRRT) is frequently employed in the management of renal failure in unstable intensive care patients. At some centers, blood cultures are performed routinely while on CRRT to monitor for occult bacteremia. We questioned the role of routine blood cultures (RBC) in diagnosing underlying infections in these often afebrile patients.Design: Retrospective cohort study (1998-2003).Setting: Medical, surgical and pediatric intensive care units in a tertiary care teaching hospital. METHODS/MEASUREMENTS: We undertook a retrospective chart review of all 101 episodes of CRRT performed in our hospital since 1998. The primary endpoint of the study was the number of positive cultures that changed patient management. For each positive result, documented infection and parameters of sepsis were noted.Results: There were 101 treatments of CRRT in 98 patients. A total of 698 routine RBC bottles were drawn, a mean of 7.2+/-7 per patient; of those, 29 (4%) were positive in 17patients, documenting 11 bacteremias. Six positive cultures represented contaminants. In all but one case, infection was known or signs of sepsis were present prior to receipt of the culture result.Conclusions: For patients on CRRT, RBC are rarely positive, and do not detect occult infection in the absence of clinical evidence of infection for the majority of patients. Because routine cultures utilize significant resources, and can result in false-positive results, RBC should not be performed in these patients. Careful clinical monitoring, with blood cultures performed at the first clinical suggestion of an infection, should detect all clinically relevant infections. [ABSTRACT FROM AUTHOR]

Abstract: Over-exploitation and fragmentation are serious problems for tropical forests. Most sustainable forest management practices avoid clear-cuts and apply selective logging systems focused on a few commercial species. We applied a simulation model to estimate the impact of such selective logging scenarios on the genetic diversity and demography of four tropical tree species from French Guiana. The simulations used data on genetic and demographic composition, growth, phenology and pollen and seed dispersal obtained for Dicorynia guianensis, Sextonia rubra, Symphonia globulifera and Vouacapoua americana at the experimental site in Paracou. Whereas Symphonia globulifera serves as a model for a species with low logging pressure, the other three species represent the most exploited tree species in French Guiana. In simulations with moderate logging, typical for French Guiana, with large cutting diameter (>60cm diameter) and long cutting cycles (65 years), the two species V. americana and Sextonia rubra were not able to recover their initial stock at the end of the rotation period, with a large decrease in the number of individuals and in basal area. Under a more intensive logging system (cutting diameter >45cm diameter, cutting cycles of 30 years) that is common practice in the Brazilian Amazon, only Symphonia globulifera showed no negative impact. Generally, the differences between the genetic parameters in the control scenarios without logging and the logging scenarios were surprisingly small. The main reasons for this were the overlapping of generations and the effective dispersal ability of gene vectors in all species, which guarantee relative homogeneity of the genetic structure in different age classes. Nevertheless, decreasing the population size by logging reduced the number of genotypes and caused higher genetic distances between the original population and the population at the end of the logging cycles. Sensitivity analysis showed that genetic changes in the logging scenarios were principally determined by the growth, densities and cutting diameter of each species, and only to a very small extent by the reproductive system including factors such as pollen and seed dispersal and flowering phenology. [Copyright &y& Elsevier]

A new approach, called the “variational theory of complex rays” has been developed in order to calculate the vibrations of slightly damped elastic plates in the medium-frequency range. The resolution of a small system of equations which does not result from a fine spatial discretization of the structure leads to the evaluation of effective quantities (deformation energy, vibration amplitude,…). Here, we extend this approach, which was already validated for assemblies of homogeneous substructures, to the case of heterogeneous substructures. [Copyright &y& Elsevier]

Abstract The forests in Cat Tien National Park, appear as a mosaic of different communities, distinct from each other with respect to their floristic and structural parameters. The objectives of this study are (1) to characterize the different formations occurring in the lowland part and (2) to identify the main successional trends in the area. Understanding forest succession is important for silviculture and restoration of forests and land rehabilitation, as adequate information on the ecological role of local species in the functioning of the forests is not available in Vietnam. Five plots (1 ha each) were established in the lowland part of Cat Tien National Park, where all the trees ≥ 10 cm d.b.h. (diameter at breast height) were located, measured and identified. A systematic sampling was made to assess the regeneration. Three plots (A, C and D) can be considered as secondary forests on the basis of their structural parameters. Plots A and C are dominated by Lagerstrmia calyculata and plot D by Dipterocarpus alatus. The other two plots can be regarded as mature forests. Plot B corresponds to a semideciduous formation dominated by Lagerstrmia calyculata and Fabaceae species, and plot E to an evergreen one dominated by dipterocarp species. The floristic composition of plots A and C will change in the future because dominant canopy species are rare or absent in regeneration. A correspondence analysis performed on the number of trees per species shows two kinds of successional trends: one from A to B on shallow and drier soils, and another from C to E on deeper and wetter soils. [ABSTRACT FROM AUTHOR]

Pediatric palliative care (PPC) teams address unmet needs and improve the quality of life of patients with life-limiting conditions across pediatric subspecialties. However, little is known about the timing, reasons, and nature of PPC team interventions in advanced heart diseases (AHD). Here we describe how, when, and why PPC teams interact with referred teams of children suffering from AHD. We conducted a retrospective nationwide survey among PPC teams in France. All patients referred to participating PPC teams for a cardiologic disease in 2019 were studied. Among six PPC teams, 18 patients with AHD had a PPC consultation in 2019. Six of these patients had cardiomyopathy and 12 had congenital heart disease (CHD). The median age at referral was 0.9 months for CHD and 72 months for cardiomyopathy. An antenatal diagnosis had been made for six families with CHD, and two of them were referred to PPC before birth allowing for a prenatal palliative care plan. The main reason for referral was ethical considerations (50%) followed by organization for home-based palliative care (28%). PPC teams participated in ethical discussions when asked to but also provided family support (12/18), home-based PPC (9/18), coordination of care (5/18), support of the referred team (4/18), and symptoms management (3/18) The main reason for referral to PPC was ethical considerations, but PPC interventions followed a holistic model of care. Prospective outcomes measurement and partnerships should be further developed. [ABSTRACT FROM AUTHOR]

Geometric and material dispersions of bladed disks imply some mistuning effects, which result in both the loss of cyclic symmetry properties and a vibratory response amplification in areas of high modal density. These conditions complicate the prediction of vibratory behavior, causing high modal density and extreme sensitivity to mistuning. A non-intrusive spectral stochastic method has been developed to predict the vibratory behavior of a mistuned stator vane. To apply this method to an industrial model, a Karhunen-Loève expansion and a double modal synthesis method have been combined with the stochastic method. The complete method was first tested on a simple academic model and then on an industrial stator vane sector. [ABSTRACT FROM AUTHOR]

On WEST new components will be implemented in an existing environment, emphasis has to be put on the metrology to optimize the design and the assembly. Hence, at a particular stage of the project, several components have to coexist in the limited vessel. Therefore, all the difficulty consists in validating the mechanical interfaces between existing components and new one; minimize the risk of the assembling and to maximize the plasma volume. The CEA/IRFM takes the opportunity of the ambitious project to sign a partnership with an industrial specialized in multipurpose metrology domains. To optimize the assembly procedure, the IRFM Assembly group works in strong collaboration with its industrial, to define and plan the campaigns of metrology. The paper will illustrate the organization, methods and results of the dedicated metrology campaigns have been defined and carried out in the WEST dis/assembly phase. To conclude, the future needs of metrology at CEA/IRFM will be exposed to define the next steps. [ABSTRACT FROM AUTHOR]

Abstract: We predict stand basal area (BA) from small footprint LiDAR data in 129 one-ha tropical forest plots across four sites in French Guiana and encompassing a great diversity of forest structures resulting from natural (soil and geological substrate) and anthropogenic effects (unlogged and logged forests). We use predictors extracted from the Canopy Height Model to compare models of varying complexity: single or multiple regressions and nested models that predict BA by independent estimates of stem density and quadratic mean diameter. Direct multiple regression was the most accurate, giving a 9.6% Root Mean Squared Error of Prediction (RMSEP). The magnitude of the various errors introduced during the data collection stage is evaluated and their contribution to MSEP is analyzed. It was found that these errors accounted for less than 10% of model MSEP, suggesting that there is considerable scope for model improvement. Although site-specific models showed lower MSEP than global models, stratification by site may not be the optimal solution. The key to future improvement would appear to lie in a stratification that captures variations in relations between LiDAR and forest structure. [Copyright &y& Elsevier]

Stator vanes which are found in axial compressors are subject to vibratory fatigue. Their division into monoblock sectors makes the prediction of their vibratory behaviour difficult by deterministic methods due to the loss of the cyclic symmetry properties and also to a high sensitivity to mistuning. The purpose is to present a robust calculation strategy based on a stochastic modelisation of the structure. The methodology has been developed first on a simplified model and then applied to an industrial case. Polynomial chaos based results are in good agreement with reference Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

Over the past decade, there has been a rapid increase in the number of initiatives involving 'for-profit' private health care providers in national tuberculosis (TB) control efforts. We reviewed 15 such initiatives with respect to contractual arrangements, quality of care and success achieved in TB control. In seven initiatives, the National TB Programme (NTP) interacted directly with for-profit providers; while in the remaining eight, the NTP collaborated with for-profit providers through intermediary not-for-profit nongovernmental organizations. All but one of the initiatives used relational 'drugs-for-performance contracts' to engage for-profit providers, i.e. drugs were provided free of charge by the NTP emphasizing that providers dispense them free of charge to patients and follow national guidelines for diagnosis and treatment. We found that 90% (range 61-96%) of new smear-positive pulmonary TB cases were successfully treated across all initiatives and TB case detection rates increased between 10% and 36%. We conclude that for-profit providers can be effectively involved in TB control through informal, but well defined drugs-for-performance contracts. The contracting party should be able to reach a common understanding concerning goals and role division with for-profit providers and monitor them for content and quality. Relational drugs-for-performance contracts minimize the need for handling the legal and financial aspects of classical contracting. We opine that further analysis is required to assess if such 'soft' contracts are sufficient to scale up private for-profit provider involvement in TB control and other priority health interventions. Copyright © 2006 World Health Organization [ABSTRACT FROM AUTHOR]

We report data on the excitation of the 2 S metastable state in helium by electrons in the presence of an intense laser field. The metastable signal is detected when the electron energy is insufficient to excite this state by itself. The additional energy comes from a pulsed CO laser developing peak intensities in the interaction region in the 10 W× cm range and requires the absorption of one or more photons. This process involves the active participation of all three bodies: the electron, the photon and the target atom. These data represent the first observation of this process when more than one photon is required. [ABSTRACT FROM AUTHOR]

This paper presents a method to simultaneously determine the wave velocity and the thickness of an unknown sample in case of overlapped ultrasonic signals. Indeed, the determination of the time delay in an ultrasonic signal can be critical to allow the simultaneous characterization of parameters of the studied material, such as the thickness and the wave velocity. Therefore, a forward-backward algorithm is applied to the overlapped signal using a reference signal in order to retrieve the excitation signal. Firstly, the method is explained and a validation on synthetic signal is performed to observe its robustness. Secondly, a time retrieval is performed on real signals to determine thickness and wave velocity in aluminium plates. The results show that this method is suitable to simultaneously retrieve thickness and wave velocity, even for overlapped signals (up to 65%), with a discrepancy as low as 1%. [ABSTRACT FROM AUTHOR]

Background: More than 500,000 hospitalized patients survive severe sepsis annually in the USA. Recent epidemiological evidence, however, demonstrated that these survivors have significant morbidity and mortality, with 3-year fatality rates higher than 70%. To investigate the mechanisms underlying persistent functional impairment in sepsis survivors, here we developed a model to study severe sepsis survivors following cecal ligation and puncture (CLP).Methods: Sepsis was induced in mice by CLP and survivors were followed for twelve weeks. Spleen and blood were collected and analyzed at different time points post-sepsis.Results: We observed that sepsis survivors developed significant splenomegaly. Analysis of the splenic cellular compartments revealed a major expansion of the inflammatory CD11b+ Ly-6CHigh pool. Serum high-mobility group box 1 (HMGB1) levels in the sepsis surviving mice were significantly elevated for 4-6 weeks after post-sepsis, and administration of an anti-HMGB1 monoclonal antibody significantly attenuated splenomegaly as well as splenocyte priming. Administration of recombinant HMGB1 to naive mice induced similar splenomegaly, leukocytosis and splenocyte priming as observed in sepsis survivors. Interestingly analysis of circulating HMGB1 from sepsis survivors by mass spectroscopy demonstrated a stepwise increase of reduced form of HMGB1 (with known chemo-attractant properties) during the first 3 weeks, followed by disulphide form (with known inflammatory properties) 4-8 weeks after CLP.Discussion: Our results indicate that prolonged elevation of HMGB1 is a necessary and sufficient mediator of splenomegaly and splenocyte expansion, as well as splenocyte inflammatory priming in murine severe sepsis survivors. [ABSTRACT FROM AUTHOR]

Background More than 500,000 hospitalized patients survive severe sepsis annually in the USA. Recent epidemiological evidence, however, demonstrated that these survivors have significant morbidity and mortality, with 3-year fatality rates higher than 70%. To investigate the mechanisms underlying persistent functional impairment in sepsis survivors, here we developed a model to study severe sepsis survivors following cecal ligation and puncture (CLP). Methods Sepsis was induced in mice by CLP and survivors were followed for twelve weeks. Spleen and blood were collected and analyzed at different time points post-sepsis. Results We observed that sepsis survivors developed significant splenomegaly. Analysis of the splenic cellular compartments revealed a major expansion of the inflammatory CD11b+ Ly-6CHigh pool. Serum high-mobility group box 1 (HMGB1) levels in the sepsis surviving mice were significantly elevated for 4-6 weeks after post-sepsis, and administration of an anti-HMGB1 monoclonal antibody significantly attenuated splenomegaly as well as splenocyte priming. Administration of recombinant HMGB1 to naive mice induced similar splenomegaly, leukocytosis and splenocyte priming as observed in sepsis survivors. Interestingly analysis of circulating HMGB1 from sepsis survivors by mass spectroscopy demonstrated a stepwise increase of reduced form of HMGB1 (with known chemo-attractant properties) during the first 3 weeks, followed by disulphide form (with known inflammatory properties) 4-8 weeks after CLP. Discussion Our results indicate that prolonged elevation of HMGB1 is a necessary and sufficient mediator of splenomegaly and splenocyte expansion, as well as splenocyte inflammatory priming in murine severe sepsis survivors. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We aimed to study the determinants of neonatal weight loss measured on the third day of life in term-infants. DESIGN: The EDEN mother-child cohort is a prospective study that recruited 2002 pregnant women before 24 weeks of gestation in two French university hospitals. Neonates were weighed every day until discharge that occurred on average 4.5 days after birth. Altogether, 1557 healthy term neonates with data on weight at day 3 and feeding mode available were included. The outcome variable was weight loss at day 3 (D3WL), expressed as a percentage of birth weight lost in the first 3 days of life. Our main explanatory variables were maternal pre-pregnancy body mass index (BMI), gestational weight gain, gestational diabetes, birth weight, gestational age and feeding mode. RESULTS: Factors associated with greater D3WL, whatever the feeding mode, were: higher birth weight, gestational diabetes and caesarean section; higher gestational age was associated with a reduced D3WL. The association between maternal pre-pregnancy BMI and D3WL differed by feeding mode (interaction p value=0.0002). In breastfed babies, mean D3WL ranged from 4.9% for neonates of underweight mothers to 5.8% for neonates of obese mothers (p trend=0.0005). In formula-fed babies, D3WL was highest for neonates of underweight mothers (4.1%) and lowest for those of obese mothers (2.6%) (p trend=0.01). CONCLUSIONS: The lower D3WL in formula-fed neonates, especially in neonates of obese mothers, suggests a relative overfeeding in the early days compared with breastfed neonates, which may potentially have consequences on later health. Overweight and obese mothers may need extra support to prevent early breastfeeding discontinuation. [ABSTRACT FROM AUTHOR]

Positive aboveground biomass trends have been reported from old-growth forests across the Amazon basin and hypothesized to reflect a large-scale response to exterior forcing. The result could, however, be an artefact due to a sampling bias induced by the nature of forest growth dynamics. Here, we characterize statistically the disturbance process in Amazon old-growth forests as recorded in 135 forest plots of the RAINFOR network up to 2006, and other independent research programmes, and explore the consequences of sampling artefacts using a data-based stochastic simulator. Over the observed range of annual aboveground biomass losses, standard statistical tests show that the distribution of biomass losses through mortality follow an exponential or near-identical Weibull probability distribution and not a power law as assumed by others. The simulator was parameterized using both an exponential disturbance probability distribution as well as a mixed exponential–power law distribution to account for potential large-scale blowdown events. In both cases, sampling biases turn out to be too small to explain the gains detected by the extended RAINFOR plot network. This result lends further support to the notion that currently observed biomass gains for intact forests across the Amazon are actually occurring over large scales at the current time, presumably as a response to climate change. [ABSTRACT FROM AUTHOR]

TSAP6 (tumor suppressor-activated pathway 6), also known as Steap3, is a direct p53 transcriptional target gene. It regulates protein secretion, for example translationally controlled tumor protein (TCTP), which is implicated in tumor reversion. In keeping with the latter, we show herein that TSAP6 is a glycosylated protein present in the trans-Golgi network, endosomal–vesicular compartment and cytoplasmic membrane. To further investigate the physiological function of TSAP6, we have generated TSAP6-deficient mice. These mice exhibit microcytic anemia with abnormal reticulocyte maturation and deficient transferrin receptor downregulation, a process known to be dependent on exosomal secretion. Moreover, we provide direct evidence that exosome production is severely compromised in TSAP6-null cells. Finally, we show that the DNA damage-induced p53-dependent nonclassical exosomal secretory pathway is abrogated in TSAP6-null cells. Given the fact that exosomes are used as cell-free vaccines against cancer and that they could be involved in the biogenesis and spread of human immunodeficiency virus, it is important to understand their regulation. The results presented here provide the first genetic demonstration that exosome formation is a tightly controlled biological process dependent of TSAP6.Cell Death and Differentiation (2008) 15, 1723–1733; doi:10.1038/cdd.2008.104; published online 11 July 2008 [ABSTRACT FROM AUTHOR]

A letter to the editor about the initiatives to recruit young scientists to do quantitative ecology research is presented.

SiO is a promising negative electrode material to increase Li-ion batteries specific energy thanks to its high capacity and stability. However it needs to be blended in low amounts with graphite because of its poor first cycle efficiency. Here we implement new Li doped carbon coated SiO material that overcomes this limitation and enables higher energy density cells. Reference SiO grade is compared to pre-lithiated materials and SiO content up to 20% blend with graphite are evaluated in pouch and 21700 cells with more than 500 cycles obtained at 90% depth of discharge. Reaction mechanism is proposed for standard as well as pre-lithiated SiO, and generalized for SiO x. Finally we discuss behavior in hard casing full cell using this simple model to calculate volume expansion. We show with steric consideration that 40% SiO is likely the ultimate ratio practically useable in cylindrical cells. • Li doped carbon coated SiO is implemented in industry representative 21700 cell. • Influence of SiO content in negative electrode is evaluated up to 20%wt. • A reaction mechanism is proposed for SiO x to calculate volume expansion. • Maximum allowed SiO–C content in 21700 cell is discussed based on this calculation. [ABSTRACT FROM AUTHOR]