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Abstract: Submarine canyon heads are key areas for understanding the triggering factors of gravity currents responsible for the transfer of detrital sediment to the deep basins. This contribution offers a detailed picture of canyon heads off La Réunion Island, with high-resolution multibeam bathymetry in the water depth range of 4–220m. The present feeding of the Cilaos turbidite system, one of the largest modern volcaniclastic systems in the world, is deduced from morphological and sedimentological interpretations of newly acquired data. The study highlights small-scale sedimentary features indicating hydrodynamic and sedimentary processes. A direct connexion between the Saint-Etienne river mouth and submarine canyons is evidenced by the complete incision of the shelf and the presence of canyon heads connected to the modern deltaic bar. This direct connection, supplied by river torrential floods (cyclonic floods every two or three years), suggests the continuity of high-density fluvial flows to submarine gravity flows, forming hyperpycnal flows in the canyon. The initiation of secondary submarine gravity flows by storm waves (large austral waves and cyclonic waves) is also proposed for submarine canyons with large canyon heads developed in the surf zone from a sandy coastal bar. Bedforms in active canyon axis are considered as an indicator of the frequent activity of high-density turbidity currents. Moreover, a morphological record of last glacial and deglacial sea level variations is preserved, and particularly the Last Glacial Maximum sea level with the presence of small vertical cliffs, observed in this bathymetric data, which likely corresponds to a paleo-shoreline or paleo-reefs. [Copyright &y& Elsevier]

Abstract: A series of graphite/LFP commercial cells, stored under 3 different conditions of temperature (30, 45, and 60 °C) and SOC (30, 65, and 100%) during up to 8 months, are disassembled and analyzed in order to identify aging phenomena. The recovered positive and negative electrodes are studied using X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and electrochemical testing. The maximum lithium stoichiometry in the recovered cathodes, derived both from XRD data and from electrochemical titration, decreases with an increase of storage temperature and storage SOC. This result confirms that the capacity fade of the commercial cells is caused by the loss of cyclable lithium. From capacity measurements on individual electrodes, any loss of active material is ruled out. Cyclable lithium loss arises from the growth of the solid electrolyte interphase at the anode, as outlined by the presence of a thick and fluffy film at the graphite particle surface for severe aging conditions (e.g., T = 60 °C and SOC = 100%) and an increase of the impedance. Evidence for side reactions at the LFP electrode is provided as well, as demonstrated by the presence of F-rich particles and an impedance increase for the electrodes that aged the most. [Copyright &y& Elsevier]

Summary: Congenital thoracic malformations (CTMs) are a heterogeneous group of rare disorders that may involve the airways or lung parenchyma. The authors have focused on the condition that causes the most controversy, namely, congenital cystic adenomatoid malformation (CCAM). The reported incidence is 3.5 and 0.94 per 10,000 live births for CTMs and CCAMs respectively. Ultrasound is the antenatal imaging modality of choice for screening for CCAMs whilst magnetic resonance imaging is complimentary for morphological and volumetric evaluation of the foetal lung. Most CCAMs are detected antenatally with only a small proportion presenting postnatally. Only a few CCAMs cause foetal problems, with foetal hydrops being the best predictor of death. Although many CCAMs regress during pregnancy, most remain detectable postnatally by CT scans. Surgical excision of symptomatic lesions is relatively straightforward, but management of asymptomatic lesions is controversial. Some surgeons adopt a “wait and see” approach operating only on those patients who develop symptoms, but others operate on asymptomatic patients usually within the first year of life. Due to the potential of malignant transformation, children should have long term follow up. There is an urgent need to delineate the natural history of antenatally detected CCAMs to guide future management. [ABSTRACT FROM AUTHOR]

An aging mode! of a commercial graphite/LiFePO4 cell is developed that takes into account side-reaction kinetics and solvent- diffusion limitations across growing passive films at both electrodes. Additionally, a progressive loss of active material at the anode is implemented as an empirical function of current density, temperature and lithium content in the anode particles. The model is calibrated using l-year aging experiments under eight different conditions, consisting either of cycling or storage. Side-reaction and passive-film parameters are adjusted by means of the aging data of OCP-stored cells, and cycling conditions are simulated based on that set of parameters. A good agreement is found between cycling experiments and simulations if the loss of anode active material is dependent on the lithium content in the particles, with more loss experienced for the Li-rich particles. Still, simulations progressively depart from experiments for the most severe conditions (cycling at 45°C), which suggests the existence of an additional aging phenomenon that is not accounted for in the present model. Once the model is validated, simulations are readily performed at longer time than experiments in order to determine the battery lifetime under various aging conditions, providing they remain in the range of applicability of the model. [ABSTRACT FROM AUTHOR]

Abstract: The objective of this work is to present a low-cost methodology to monitor the displacement of continuously active landslides from ground-based optical images analyzed with a normalized image correlation technique. The performance of the method is evaluated on a series of images acquired on the Super-Sauze landslide (South French Alps) over the period 2008–2009. The image monitoring system consists of a high resolution optical camera installed on a concrete pillar located on a stable crest in front of the landslide and controlled by a datalogger. The data are processed with a cross-correlation algorithm applied to the full resolution images in the acquisition geometry. Then, the calculated 2D displacement field is orthorectified with a back projection technique using a high resolution DEM interpolated from Airborne Laser Scanning (ALS) data. The heterogeneous displacement field of the landslide is thus characterized in time and space. The performance of the technique is assessed using differential GPS surveys as reference. The sources of error affecting the results are then discussed. The strongest limitations for the application of the technique are related to the meteorological, illumination and ground surface conditions inducing partial or complete loss of coherence among the images. Small movements of the camera and the use of a mono-temporal DEM are the most important factors affecting the accuracy of the ortho-rectification of the displacement field. As the proposed methodology can be routinely and automatically applied, it offers promising perspectives for operational applications like, for instance, in early warning systems. [Copyright &y& Elsevier]

The geology of the Republic of Djibouti, in the SE Afar Triangle, is characterized by intense tectonic and bimodal volcanic activity that began as early as 25-30 Ma. Each magmatic event was accompanied by hydrothermal activity. Mineralization generally occurs as gold-silver bearing chalcedony veins and is associated with felsic volcanism. Eighty samples from mineralized hydrothermal chalcedony, quartz ± carbonate veins and breccias were studied from ten sites representing four major volcanic events that range in age from early Miocene to the present. The most recent veins are controlled by fractures at the edges of grabens established during the last 4 Myr. Gold in excess of 200 ppb is present in 30% of the samples, with values up to 16 ppm. Mineralogical compositions allowed us to identify different types of mineralization corresponding to different depths in the hydrothermal system: (1) surface and subsurface mineralization characterized by carbonate chimneys, gypsum, silica cap and quartz ± carbonate veins that are depleted in metals and Au; (2) shallow banded chalcedony ± adularia veins related to boiling that contain up to 16 ppm Au, occurring as native gold and electrum with pyrite, and tetradymite; (3) quartz veins with sulfides, and (4) epidote alteration in the deepest hydrothermal zones. Samples in which pyrite is enriched in As tend to have a high Au content. The association with bimodal volcanism, the occurrence of adularia and the native Au and electrum in banded chalcedony veins are typical of epithermal systems and confirm that this type of mineralization can occur in a young intracontinental rift system. [ABSTRACT FROM AUTHOR]

A mathematical model of the LiFePO4 electrode is developed that is based on a thermodynamically-consistent treatment of solid-state lithium transport, in which the active material is described as a nonideal binary solution of Li-intercalated and empty sites. The nonideality is derived from the experimental open-circuit potential and manifested in a concentration-dependent diffusion coefficient throughout the entire composition range. Under certain operating conditions, a diffuse phase-boundary between Li-poor and Li-rich area is predicted. Furthermore, the actual active-particle-size distribution within the electrodes is captured by three different particle groups in the model. Without embedding porous-electrode effects into the model, simulation/experiment comparisons for three electrodes recovered from different commercial cells at rates up to 1C show the robustness of the variable solid-state diffusivity and particle-size distribution for simulating galvanostatic charges/discharges. In addition, it allows for analysis of the experimental data of various electrodes and to understand their rate limitations. Based on model-parameter comparison between the three designs, the resistive-reactant effect is identified as an additional limiting effect in the electrode comprising nano-particles. The proposed model is a promising candidate for various macroscopic applications, e.g., implementation into 3D battery-pack models for battery management system or comprehensive aging studies. [ABSTRACT FROM AUTHOR]

A mathematical model of a Li/LiPON (Lithium Phosphorus Oxynitride)/LiCoO2 all-solid-state thin-film microbattery was developed. It is isothermal, one-dimensional and takes into account lithium diffusion and electron migration in the positive electrode, migration of lithium ions in the solid electrolyte, and charge-transfer kinetics at the electrode/electrolyte interfaces. Model input parameters are determined for the case of a reference microbattery available on the market using a variety of electrochemical techniques such as galvanostatic intermittent titration technique and electrochemical impedance spectroscopy. A good agreement is found between simulation and charge/discharge experimental data, both in galvanostatic and potentiostatic operation, which therefore validates the model. Finally, the temperature dependence of input parameters is introduced into the model, which allows for predicting microbattery operation at different temperatures. [ABSTRACT FROM AUTHOR]

Capacity loss of a commercial graphite/LiFePO4 cell during either open-circuit-potential storage or under cycling conditions at 25 and 45°C during one year is analyzed with the aid of postmortem analyses and simulations of the cell performance decay over the course of aging. An in-depth understanding of capacity-loss mechanisms under both storage and cycling conditions is gained by refining some parameters of a single-particle model of the cell at different extents of aging. The simulation-based analysis of the aging data reveals that the capacity fade during cell storage only results from the loss of cyclable lithium because of side reactions whereas the loss of graphite active material is an additional source of aging for the cells under cycling conditions. A simple kinetic analysis of electrode/electrolyte interactions is provided for the cells under storage conditions. Moreover, the growth of solid-electrolyte interphase (SEI) at the graphite electrode under storage conditions is simulated in order to refine the solvent-reduction kinetic parameters and solvent diffusion coefficient in the SEI layer. From the analysis, it is shown that the SEI growth during storage is under mixed kinetic/diffusion control. [ABSTRACT FROM AUTHOR]

Rationale: Bronchopulmonary dysplasia is the most common chronic respiratory disease in premature infants. Genetic factors might contribute to bronchopulmonary dysplasia susceptibility.Objectives: To identify genetic variants involved in bronchopulmonary dysplasia through a genome-wide association study.Methods: We prospectively evaluated 418 premature neonates (gestational age <28 wk), of whom 22% developed bronchopulmonary dysplasia. Two discovery series were created, using a DNA pooling strategy in neonates from white and African ancestry. Polymorphisms associated with the disease were confirmed in an independent replication population. Genes were then explored by fine mapping and associations were replicated in an external Finnish population of 213 neonates. Validated genes expression patterns were studied in rat lung, after air or hyperoxia exposure.Measurements and Main Results: SPOCK2 gene was identified by both discovery series. The most significant polymorphism (rs1245560; P = 1.66 × 10(-7)) was confirmed by individual genotyping, and in the replication population (P = 0.002). Fine mapping confirmed the association of rs1245560 with bronchopulmonary dysplasia in both white and African populations with adjusted odds ratios of 2.96 (95% confidence interval [CI], 1.37-6.40) and 4.87 (95% CI, 1.88-12.63), respectively. In white neonates, rs1049269 was also associated with the disease (odds ratio, 3.21; 95% CI, 1.51-6.82). These associations were replicated in the Finnish population. In newborn rat lungs, SPOCK2 mRNA levels markedly increased during the alveolar stage of lung development. After rat exposure to hyperoxia, SPOCK2 expression increased relative to air-exposed controls.Conclusions: We identified SPOCK2 as a new possible candidate susceptibility gene for bronchopulmonary dysplasia. Its lung expression pattern points toward a potential role in alveolarization. [ABSTRACT FROM AUTHOR]

The aging behavior of a commercial 2.3 Ah graphite/LFP cell during a year of cycling or storage at either 25 or 45°C is investigated. The performance decline of the cells during the aging period is monitored by non-destructive electrochemical techniques and is discussed in detail. An in-depth analysis of the aging results reveals that aging manifests itself more in terms of capacity loss rather than in terms of impedance increase, regardless of the cycling or storage conditions and of the temperature. The capacity fade is larger at 45°C than at 25°C, regardless of the cycling or storage conditions, and at a same temperature, cycling conditions are always more detrimental to capacity fade than storage conditions. The loss of cyclable lithium is identified as the main source of capacity fade in all cases, and for the cells aged at 45°C, a partial loss of graphite active material is suspected as well towards the end of the aging period. [ABSTRACT FROM AUTHOR]

Objective A decrease in the volume of congenital pulmonary malformations (CPM) can be observed on prenatal ultrasonography, but the underlying mechanism for this phenomenon is unknown. Our objective was to identify factors associated with the prenatal reduction in size of cystic and/or hyperechoic lung lesions. Methods This was a retrospective study of cases with a prenatal diagnosis of hyperechoic and/or cystic lung lesion. The extent of reduction in lesion size was calculated from ultrasound measurements. Clinical, ultrasound, radiological and histological data were tested for their relationship with prenatal CPM reduction. Results In a 4-year period, 36 patients were referred with a cystic and/or hyperechoic fetal lung lesion diagnosed at a mean gestational age of 23.4 weeks. The lesions were cystic in 16 cases (44%), hyperechoic in 12 (33%) and both in eight (22%). The malformation was no longer visible before birth (apparent disappearance) in nine cases (25%), shrank by 18-90% in 15 (42%) and did not reduce in 12 (33%). Findings on postnatal computed tomography were always abnormal. Isolated hyperechoic lesions were significantly more likely to shrink in utero. The mean reductions were 79%, 35% and 19%, for isolated hyperechoic, cystic and mixed lesions, respectively ( P = 0.001). Only 8% of hyperechoic lesions demonstrated no volume reduction, as compared to 50% and 42% of cystic and mixed lesions, respectively ( P = 0.03). Greater gestational age at birth was also associated with a decrease in the incidence of malformations ( P = 0.02). In cases that underwent surgery, hyperechoic lesions were linked to a variety of pathological diagnoses, whereas cystic lesions were all described histologically as congenital cystic adenomatoid malformations. Conclusions Prenatal size reduction of fetal lung malformations is associated with isolated hyperechogenicity and greater gestational age at birth. This might result from the resumption of normal lung development after local disruption of lung growth. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Lithium diffusion coefficient (D) in LiyFeSO4F is investigated by means of three electrochemical techniques, namely potentiostatic intermittent titration technique (PITT), galvanostatic intermittent titration technique (GITT), and galvanostatic charge/discharge at different C-rates. The analytic equations used for analyzing PITT and GITT are based on radial diffusion in spherical particles, which is more suitable to the type of electrode studied here than the original equations derived by Wen et al. [J. Electrochem. Soc., 126, 2258 (1979).] for a slab geometry. While PITT and GITT analyses with the analytic equations are only valid in the partial solid solution regions (y ≤0.29 and y ≤0.83 in LiyFeSO4F), the analysis of galvanostatic charge/discharge with a mathematical model allows for the determination of D over the entire lithium composition range. The average D values found with PITT and GITT analyses are in good agreement with each other, and of the same order as those reported for LiyFePO4 in the literature (ca. 10-14 cm2/s); However, D is larger for LiyFeSO4F in the Li-rich composition range than in the Li-poor one, whereas it is the opposite for LiyFePO4. This result could explain why LiyFeSO4F has a better rate capability on discharge than LiyFePO4. [ABSTRACT FROM AUTHOR]

Studies based on skin and challenge tests have shown that 12-60% of children with suspected betalactam hypersensitivity were allergic to betalactams. Responses in skin and challenge tests were studied in 1865 children with suspected betalactam allergy (i) to confirm or rule out the suspected diagnosis; (ii) to evaluate diagnostic value of immediate and non-immediate responses in skin and challenge tests; (iii) to determine frequency of betalactam allergy in those children, and (iv) to determine potential risk factors for betalactam allergy. The work-up was completed in 1431 children, of whom 227 (15.9%) were diagnosed allergic to betalactams. Betalactam hypersensitivity was diagnosed in 50 of the 162 (30.9%) children reporting immediate reactions and in 177 of the 1087 (16.7%) children reporting non-immediate reactions (p < 0.001). The likelihood of betalactam hypersensitivity was also significantly higher in children reporting anaphylaxis, serum sickness-like reactions, and (potentially) severe skin reactions such as acute generalized exanthematic pustulosis, Stevens-Johnson syndrome, and drug reaction with systemic symptoms than in other children (p < 0.001). Skin tests diagnosed 86% of immediate and 31.6% of non-immediate sensitizations. Cross-reactivity and/or cosensitization among betalactams was diagnosed in 76% and 14.7% of the children with immediate and nonimmediate hypersensitivity, respectively. The number of children diagnosed allergic to betalactams decreased with time between the reaction and the work-up, probably because the majority of children with severe and worrying reactions were referred for allergological work-up more promptly than the other children. Sex, age, and atopy were not risk factors for betalactam hypersensitivity. In conclusion, we confirm in numerous children that (i) only a few children with suspected betalactam hypersensitivity are allergic to betalactams; (ii) the likelihood of betalactam allergy increases with earliness and/or severity of the reactions; (iii) although non-immediate- reading skin tests (intradermal and patch tests) may diagnose non-immediate sensitizations in children with non-immediate reactions to betalactams (maculopapular rashes and potentially severe skin reactions especially), the diagnostic value of non-immediate-reading skin tests is far lower than the diagnostic value of immediate- reading skin tests, most non-immediate sensitizations to betalactams being diagnosed by means of challenge tests; (iv) cross-reactivity and/or cosensitizations among betalactams are much more frequent in children reporting immediate and/or anaphylactic reactions than in the other children; (v) age, sex and personal atopy are not significant risk factors for betalactam hypersensitivity; and (vi) the number of children with diagnosed allergy to betalactams (of the immediate-type hypersensitivity especially) decreases with time between the reaction and allergological workup. Finally, based on our experience, we also propose a practical diagnostic approach in children with suspected betalactam hypersensitivity. [ABSTRACT FROM AUTHOR]

Abstract: The onset of experimental galvanostatic charge/discharge data of Li y FePO4 at low current density and at room temperature is analyzed using a single-particle mathematical model. The model contains only two adjustable parameters, namely one related to solid-state diffusion in the active particle and another one related to the surface resistance of the particle. The analysis reveals that these two parameters depend on the current density in a similar manner, meaning that there exists a correlation between them. An immediate consequence is that the onset of the experimental charge/discharge curves is properly modeled with the particle radius as a unique parameter depending on the current density. Hypotheses are made to shed light on this unusual dependence. [Copyright &y& Elsevier]