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• Similarity laws are verified in the framework of a one-dimensional heat and water vapor diffusion problem through an experimental campaign. • Two configurations of hemp concrete samples, equivalent in terms of similarity laws, are exposed to thermal and hydric stress. • Temperature and relative humidity at equivalent positions in both samples are measured and compared. • A detailed uncertainty investigation is proposed to discuss the reliability of the observed discrepancies. • The comparison of discrepancies and entire uncertainties show a good agreement between the reference and reduced configurations. Similarity law is a mathematical mapping that aims to set up equivalences between different configurations regarding the involved physical parameters, space dimensions and the duration of the configuration. These equivalences are defined by means of the dimensionless formulation of the physical model that describes a phenomenon. This concept is widely adopted in some scientific fields, notably in computational fluid dynamics. In heat and water vapor diffusion, similarities are applicable theoretically on configurations distinct in terms of material, space dimensions, duration or even imposed stress magnitude. It is worth noting that these are slow kinetic phenomena. In this regard, this study aims to verify similarities experimentally while using hemp concrete and reducing the duration of a reference experiment. Before performing measurements, two main limitations are fixed. First, by means of an experimental design, heat and moisture transfer are assumed one-dimensional. In addition, Dirichlet boundary conditions are considered at the surface that is exposed to ambient air. Mainly, temperature and relative humidity are measured at the quarter and middle of the material in order to compare the two similar configurations. Afterwards, an uncertainty study is carried out in order to discuss and justify the observed discrepancies. Following a deterministic approach, this investigation considers five sub-uncertainties which are related to : the calibration of used sensors, their positions, time of response, randomness of an experiment and the boundary condition modeling. Results show a good agreement between the reference and reduced configurations. Indeed, the discrepancies between both are entirely within the calculated confidence intervals. [ABSTRACT FROM AUTHOR]

We tested science operations strategies developed for use in remote mobile spacecraft missions, to determine whether reconnoitering a site of potential habitability prior to in-depth study (a walkabout-first strategy) can be a more efficient use of time and resources than the linear approach commonly used by planetary rover missions. Two field teams studied a sedimentary sequence in Utah to assess habitability potential. At each site one team commanded a human “rover" to execute observations and conducted data analysis and made follow-on decisions based solely on those observations. Another team followed the same traverse using traditional terrestrial field methods, and the results of the two teams were compared. Test results indicate that for a mission with goals similar to our field case, the walkabout-first strategy may save time and other mission resources, while improving science return. The approach enabled more informed choices and higher team confidence in choosing where to spend time and other consumable resources. The walkabout strategy may prove most efficient when many close sites must be triaged to a smaller subset for detailed study or sampling. This situation would arise when mission goals include finding, identifying, characterizing or sampling a specific material, feature or type of environment within a certain area. [ABSTRACT FROM AUTHOR]

Abstract: Currently the molecular basis for the clinical heterogeneity of X-linked adrenoleukodystrophy (X-ALD) is poorly understood. The genetic bases for all different phenotypic variants of X-ALD are mutations in the gene encoding the peroxisomal ATP-binding cassette (ABC) transporter, ABCD1 (formerly adrenoleukodystrophy protein, ALDP). ABCD1 transports CoA-activated very long-chain fatty acids from the cytosol into the peroxisome for degradation. The phenotypic variability is remarkable ranging from cerebral inflammatory demyelination of childhood onset, leading to death within a few years, to adults remaining pre-symptomatic through more than five decades. There is no general genotype–phenotype correlation in X-ALD. The default manifestation of mutations in ABCD1 is adrenomyeloneuropathy, a slowly progressive dying-back axonopathy affecting both ascending and descending spinal cord tracts as well as in some cases, a peripheral neuropathy. In about 60% of male X-ALD patients, either in childhood (35–40%) or in adulthood (20%), an initial, clinically silent, myelin destabilization results in conversion to a devastating, rapidly progressive form of cerebral inflammatory demyelination. Here, ABCD1 remains a susceptibility gene, necessary but not sufficient for inflammatory demyelination to occur. Although the accumulation of very long-chain fatty acids appears to be essential for the pathomechanism of all phenotypes, the molecular mechanisms underlying these phenotypes are fundamentally different. Cell autonomous processes such as oxidative stress and energy shortage in axons as well as non-cell autonomous processes involving axon–glial interactions seem pertinent to the dying-back axonopathy. Various dynamic mechanisms may underlie the initiation of inflammation, the altered immune reactivity, the propagation of inflammation, as well as the mechanisms leading to the arrest of inflammation after hematopoietic stem cell transplantation. An improved understanding of the molecular mechanisms involved in these events is required for the development of urgently needed therapeutics. [Copyright &y& Elsevier]

The incidence of vestibular disorders and vertigo during childhood is increasing and pediatric clinicians have become more sensitive to children's balance disorders; thus, there is a need for appropriate detection test procedures for peripheral vestibular hypofunction. In order to ensure a reliable diagnosis and minimize misdiagnosis, a standardized clinical procedure via careful history and clinical examination is recommended. However, children, especially, are often unable to verbalize "vertigo" in a concrete manner, which often necessitates a consultation with a pediatrician holding nonspecific symptoms. The so-called suppression of the head impulse test (SHIMPs) represents a modification of the video head impulse test (HIMP) and is used for a more sensitive assessment of residual vestibular functions. In adults, SHIMPs are already an established diagnostic method. Nevertheless, to date, nothing is known about the applicability and standard values in childhood. In this monocentric, prospective study, we investigated whether SHIMPs enable a sensitive functional analysis of the vestibular system in healthy children of different ages. For this purpose, SHIMPs were performed in 40 children aged 3–18 years. In this study, we demonstrated that SHIMPs can be easily performed in children (3–18 years). It is vital that the test be appropriately explained for children to ensure sufficient test tolerance and compliance. SHIMPs are a helpful supplement to clinically established vestibular tests such as the HIMP in pediatric vestibular balance disorder diagnostics and can be integrated into the clinical routine, especially in children who have minimal verbal abilities or understanding of the instructions for HIMP. Similar to the HIMP, SHIMPs are characterized by a short test duration and a high tolerance. [ABSTRACT FROM AUTHOR]

Abstract: It has been confirmed that clock genes, as well as the pineal hormone, have a role in the hypothalamic suprachiasmatic nucleus, the circadian endogenous pacemaker. It seems that the peripheral clock genes in the cells of the immune system subtly control biorhythms; their seeming lack of impact only showing that they work well. Some biorhythms even seem to be independent of a light/dark circadian regime. This apparent conflict in the mammalian time structure can be resolved by a two-clocks control model involving: (a) the endogenous gene clock, which is dominant in the neural system and (b) the exogenous clock of the immune system. Interactions between these two clocks can explain both the frequently observed individual differences in circadian rhythms and the subtle role of the peripheral clock genes. The endogenous clock facilitates an alternation in the immune system which counters external attacks in daytime and induces repair and advancement by night. [Copyright &y& Elsevier]

Abstract: We have obtained experimental evidence for a vortex that mediates between adjacent fluxoid states in a mesoscopic superconducting ring with nonuniform width. We have obtained information about the path of this vortex. For small fluxoid numbers the vortex crosses the sample through the narrowest part and for large fluxoid numbers through the widest part. We review our predictions for critical points. Our results are in agreement with the existent theory. [Copyright &y& Elsevier]

Abstract: Past initiatives to address surveillance and reconnaissance mission planning mainly focused on low-level control aspects such as real-time path planning and collision avoidance algorithms in limited environment. However, few efforts have been spent on high-level real-time task allocation. It is believed that automated decision capabilities supporting real-time resource allocation for sensor control and interactions might significantly reduce user workload, focusing attention on alternate tasks and objectives while assigning hard computational tasks to artificial agents. In this paper, we propose a new hybrid genetic algorithm to solve the dynamic vehicle routing problem with time windows, in which a group of airborne sensors are engaged in a reconnaissance mission evolving in a dynamic uncertain environment involving known and unknown targets/threats. In that context, visiting a target may consist in carrying out a collection of subtasks such as search, detect, recognize and confirm suspected targets, discover and confirm new ones. The approach consists in concurrently evolving two populations of solutions to minimize total travel time and temporal constraint violation using genetic operators combining variations of key concepts inspired from routing techniques and search strategies. A least commitment principle in servicing scheduled customers is also exploited to potentially improve solution quality. [Copyright &y& Elsevier]

Abstract: The methane oxidation potential of a landfill cover with capillary barrier was investigated in an experimental plant (4.8m×0.8m×2.1m). The cover soil consisted of two layers, a mixture of compost plus sand (0.3m) over a layer of loamy sand (0.9m). Four different climatic conditions (summer, winter, spring and fall) were simulated. In and outgoing fluxes were measured. Gas composition, temperature, humidity, matrix potential and gas pressure were monitored in two profiles. CH4 oxidation rate within the investigated top cover ranged from 98% to 57%. The minimum was observed for a short time after irrigation. Temperature distribution, gas concentration profiles and lab-scaled batch experiments indicate that before irrigation the highest oxidising activity took place in a depth of about 30cm. After irrigation the oxidising horizon seemed to migrate upwards since methanotrophic bacteria develop better there due to an adequate supply with oxygen. It can be assumed that the absence of oxygen is one of the most important limiting factors for the CH4 oxidation process. Abrupt cross-overs between horizons of different soil material may lead to zones of increased water saturation and decreased soil respiration. [Copyright &y& Elsevier]

Abstract: To prepare transparent chitosan/β-glycerophosphate (βGP) pseudo-thermosetting hydrogels, the deacetylation degree (DD) of chitosan has been modified by reacetylation with acetic anhydride. Two methods (I and II) of reacetylation have been compared and have shown that the use of previously filtered chitosan, dilution of acetic anhydride and reduction of temperature in method II improves efficiency and reproducibility. Chitosans with DD ranging from 35.0 to 83.2% have been prepared according to method II under homogeneous and non-homogeneous reacetylation conditions and the turbidity of chitosan/βGP hydrogels containing homogeneously or non-homogeneously reacetylated chitosan has been investigated. Turbidity is shown to be modulated by the DD of chitosan and by the homogeneity of the medium during reacetylation, which influences the distribution mode of the chitosan monomers. The preparation of transparent chitosan/βGP hydrogels requires a homogeneously reacetylated chitosan with a DD between 35 and 50%. [Copyright &y& Elsevier]

Abstract: To prepare transparent chitosan/β-glycerophosphate (βGP) pseudo-thermosetting hydrogels, the deacetylation degree (DD) of chitosan has been modified by reacetylation with acetic anhydride. Two methods (I and II) of reacetylation have been compared and have shown that the use of previously filtered chitosan, dilution of acetic anhydride and reduction of temperature in method II improves efficiency and reproducibility. Chitosans with DD ranging from 35.0 to 83.2% have been prepared according to method II under homogeneous and non-homogeneous reacetylation conditions and the turbidity of chitosan/βGP hydrogels containing homogeneously or non-homogeneously reacetylated chitosan has been investigated. Turbidity is shown to be modulated by the DD of chitosan and by the homogeneity of the medium during reacetylation, which influences the distribution mode of the chitosan monomers. The preparation of transparent chitosan/βGP hydrogels requires a homogeneously reacetylated chitosan with a DD between 35 and 50%. [Copyright &y& Elsevier]

This review presents a critical analysis of covalently and ionically crosslinked chitosan hydrogels and related networks for medical or pharmaceutical applications. The structural basis of these hydrogels is discussed with reference to the specific chemical interactions, which dictate gel formation. The synthesis and chemistry of these hydrogels is discussed using specific pharmaceutical examples. Covalent crosslinking leads to formation of hydrogels with a permanent network structure, since irreversible chemical links are formed. This type of linkage allows absorption of water and/or bioactive compounds without dissolution and permits drug release by diffusion. pH-controlled drug delivery is made possible by the addition of another polymer. Ionically crosslinked hydrogels are generally considered as biocompatible and well-tolerated. Their non-permanent network is formed by reversible links. Ionically crosslinked chitosan hydrogels exhibit a higher swelling sensitivity to pH changes compared to covalently crosslinked chitosan hydrogels. This extends their potential application, since dissolution can occur in extreme acidic or basic pH conditions. [Copyright &y& Elsevier]

The aim of this review was to provide a detailed overview of physical chitosan hydrogels and related networks formed by aggregation or complexation, which are intended for biomedical applications. The structural basis of these systems is discussed with particular emphasis on the network-forming interactions, the principles governing their formation and their physicochemical properties. An earlier review discussing crosslinked chitosan hydrogels highlighted the potential negative influence on biocompatibility of covalent crosslinkers and emphasised the need for alternative hydrogel systems. A possible means to avoid the use of covalent crosslinkers is to prepare physical chitosan hydrogels by direct interactions between polymeric chains, i.e. by complexation, e.g. polyelectrolyte complexes (PEC) and chitosan/poly (vinyl alcohol) (PVA) complexes, or by aggregation, e.g. grafted chitosan hydrogels. PEC exhibit a higher swelling sensitivity towards pH changes compared to covalently crosslinked chitosan hydrogels, which extends their potential application. Certain complexed polymers, such as glycosaminoglycans, can exhibit interesting intrinsic properties. Since PEC are formed by non-permanent networks, dissolution can occur. Chitosan/PVA complexes represent an interesting alternative for preparing biocompatible drug delivery systems if pH-controlled release is n/ot required. Grafted chitosan hydrogels are more complex to prepare and do not always improve biocompatibility compared to covalently crosslinked hydrogels, but can enhance certain intrinsic properties of chitosan such as bacteriostatic and wound-healing activity. [Copyright &y& Elsevier]

Applying the HFB theory with the effective interaction D1S of Gogny, two kinds of “hyperheavy nuclei” were discovered: true “bubbles” with practically vanishing nuclear density in the central region of the nucleus, and “semi-bubbles” (“unsaturated nuclei”) with a reduced but finite density near the nuclear center. Semi-bubbles are found to be stable with regard to the emission of a neutron or a proton for nucleon numbers A and charge numbers Z in the ranges 292⪝A⪝750 and 120⪝Z⪝240, and true bubbles for 750⪝A⪝920 and 240⪝Z⪝280, respectively. For a limited number of nuclear species, a third type of hyperheavy nuclei with a finite, strongly reduced, halo-like central density (“internal halo nuclei”) is found. Coexistence of bubble and semi-bubble solutions for given nucleon and charge numbers is frequently obtained, the semi-bubbles being the ground states for A⪝780 and Z⪝240, and the true bubbles for the heavier nuclear species. The dominant disintegration mode of the semi-bubbles is α-decay and of the true bubbles is fission. The α-lifetimes of semi-bubbles range from several seconds down to ≃10−6 s, according to a simple semi-phenomenological formula. The fission lifetimes vary strongly as functions of the neutron and proton numbers ranging between years (for semi-bubbles) and microseconds or less (for true bubbles). [Copyright &y& Elsevier]

Large scale Hartree–Fock–Bogoliubov (HFB) calculations with the finite-range Gogny force D1S have been performed in order to extract the corresponding theoretical average mass dependence of the nuclear gap values. Good agreement with experimental data from the three-point filter Δ(3)(N) with N odd has been found for both the neutron and proton gaps. The results of our study support earlier findings [W. Satul̷a, J. Dobaczewski, W. Nazarewicz, Phys. Rev. Lett. 81 (1998) 3599] that the mass dependence of the gap is much weaker than the so far accepted 12 A−1/2 MeV law. [Copyright &y& Elsevier]

The members of the nuclear receptor superfamily are known to mediate a wide array of basic biological processes, such as regulation of cell growth and differentiation, and induction of apoptosis. In several human malignancies, this central control function of nuclear receptors is disturbed, which seems to play an important role in tumor development and progression. Many nuclear receptor genes have been reported to be downregulated in malignancies; however, only a few mutations, gene arrangements, deletions or similar genetic changes have been shown to occur in these tumors.During the last decade, increasing attention has been directed towards epigenetic mechanisms of gene regulation such as DNA methylation. Many nuclear receptor genes can be silenced through aberrant methylation in tumors; epigenetic silencing, therefore, represents an additional mechanism that modifies expression of key genes during carcinogenesis.This review will give insights into the role of DNA methylation in the silencing of nuclear receptor genes and its involvement in human malignancies. [Copyright &y& Elsevier]

The author comments on the use a transversus abdominis plane (TAP) block in postoperative analgesia, which involves injection of a local anaesthetic solution into a plane between internal oblique (IO) and transversus abdominis (TA) muscles. The results of prospective randomized trials have shown the analgesic efficacy of the block compared with placebo. The author recommends assessing the value of the TAP block in plastic surgery of the abdominal wall and parietal abdominal wall repair procedures.

Atypical EGFR mutations occur in 10%-30% of non-small-cell lung cancer (NSCLC) patients with EGFR mutations and their sensitivity to classical epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKI) is highly heterogeneous. Patients harboring one group of uncommon, recurrent EGFR mutations (G719X, S768I, L861Q) respond to EGFR-TKI. Exon 20 insertions are mostly insensitive to EGFR-TKI but display sensitivity to exon 20 inhibitors. Clinical outcome data of patients with very rare point and compound mutations upon systemic treatments are still sparse to date. In this retrospective, multicenter study of the national Network Genomic Medicine (nNGM) in Germany, 856 NSCLC cases with atypical EGFR mutations including co-occurring mutations were reported from 12 centers. Clinical follow-up data after treatment with different EGFR-TKIs, chemotherapy and immune checkpoint inhibitors were available from 260 patients. Response to treatment was analyzed in three major groups: (i) uncommon mutations (G719X, S7681, L861Q and combinations), (ii) exon 20 insertions and (iii) very rare EGFR mutations (very rare single point mutations, compound mutations, exon 18 deletions, exon 19 insertions). Our study comprises the largest thus far reported real-world cohort of very rare EGFR single point and compound mutations treated with different systemic treatments. We validated higher efficacy of EGFR-TKI in comparison to chemotherapy in group 1 (uncommon), while most exon 20 insertions (group 2) were not EGFR-TKI responsive. In addition, we found TKI sensitivity of very rare point mutations (group 3) and of complex EGFR mutations containing exon 19 deletions or L858R mutations independent of the combination partner. Notably, treatment responses in group 3 (very rare) were highly heterogeneous. Co-occurring TP53 mutations exerted a non-significant trend for a detrimental effect on outcome in EGFR-TKI-treated patients in groups 2 and 3 but not in group 1. Based on our findings, we propose a novel nNGM classification of atypical EGFR mutations. • The EGFR-TKI efficacy of in uncommon EGFR mutations generally considered TKI sensitive was validated. • Complex EGFR mutations containing exon19del or L858R were EGFR-TKI sensitive, independent of the combination partner. • Very rare single and complex mutations, comprising 40% of atypical mutations, show a high heterogeneity of TKI sensitivity. • TP53 co-mutations may confer a detrimental outcome in TKI-treated patients with very rare EGFR mutations and exon20ins. • We propose a novel nNGM classification for atypical EGFR mutations. [ABSTRACT FROM AUTHOR]

Abstract: We formulate a microscopic theory of the decay of a compound nucleus through fission which generalizes earlier microscopic approaches of fission dynamics performed in the framework of the adiabatic hypothesis. It is based on the constrained Hartree–Fock–Bogoliubov procedure and the Generator Coordinate Method, and requires an effective nucleon–nucleon interaction as the only input quantity. The basic assumption is that the slow evolution of the nuclear shape must be treated explicitly, whereas the rapidly time-dependent intrinsic excitations can be treated by statistical approximations. More precisely, we introduce a “reference density” which represents the slow evolution of the nuclear shape by a reduced density matrix and the state of intrinsic excitations by a canonical distribution at each given shape of the nucleus. The shape of the nuclear density distribution is described by parameters (“generator coordinates”q), not by “superabundant” degrees of freedom introduced in addition to the complete set of nucleonic degrees of freedom. We first derive a rigorous equation of motion for the reference density and, subsequently, simplify this equation on the basis of the “Markov approximation”. The temperature T which appears in the canonical distribution is determined by the requirement that, at each time t, the reference density should correctly reproduce the mean excitation energy at given values of the shape parameters q. The resulting equation for the “local” temperature must be solved together with the equations of motion obtained for the reduced density matrix . [Copyright &y& Elsevier]

We present the case of an HIV-infected patient who developed life-threatening rhabdomyolysis and Fanconi syndrome 11 years after initiation of TDF-based combination antiretroviral therapy (cART). Apart from our patient, the association of rhabdomyolysis and concomitant tubular nephropathy has been reported in three other patients in the literature [[5]]. The tubular nephropathy was diagnosed as Fanconi syndrome in two patients and acute tubular necrosis in the two other patients. [Extracted from the article]

Low energy fission is described using a microscopic and time-dependent approach. Fission dynamics is derived from the evolution of a collective wave function in the restricted space generated by the quadrupole and octupole collective variables. Propagation is made by use of the Time Dependent Generator Coordinate Method with a basis set of Hartree Fock Bogoliubov states obtained from self-consistent calculations with the Gogny force. Theoretical fragment mass and kinetic energy distributions in actinide fission are presented. First calculations with selected initial states indicate that the main features of experimental mass distributions in 238U are reproduced. The peak-to-valley ratio appears to significantly depend on the parity of the initial state chosen. [Copyright &y& Elsevier]

An analysis of singular solutions at corners consisting of several different homogeneous wedges is presented for anisotropic potential theory in plane. The concept of transfer matrix is applied for a singularity analysis first of single wedge problems and then of multi-material corner problems. Explicit forms of eigenequations for evaluation of singularity exponent in the case of multi-material corners are derived both for all combinations of homogeneous Neumann and Dirichlet boundary conditions at faces of open corners and for multi-material planes with singular interior points. Perfect transmission conditions at wedge interfaces are considered in both cases. It is proved that singularity exponents are real for open anisotropic multi-material corners, and a sufficient condition for the singularity exponents to be real for anisotropic multi-material planes is deduced. A case of a complex singularity exponent for an anisotropic multi-material plane is reported, apparently for the first time in potential theory. Simple expressions of eigenequations are presented first for open bi-material corners and bi-material planes and second for a crack terminating at a bi-material interface, as examples of application of the theory developed here. Analytical solutions of these eigenequations are presented for interface cracks with any combination of homogeneous boundary conditions along the interface crack faces, and also for a special case of a crack perpendicular to a bi-material interface. A numerical study of variation of the singularity exponent as a function of inclination of a crack terminating at a bi-material interface is presented. [Copyright &y& Elsevier]

Donor derived cell free DNA (ddcfDNA) may supplant or enhance current screening and diagnostic tools for transplant rejection. Correlations between ddcfDNA, severity of rejection, and donor specific antibody (DSA) formation has been published in adult heart transplant (HT) recipients. However, there are limited data on real world use of ddcfDNA in pediatric HT patients. We performed a retrospective analysis of ddcfDNA levels at a single center [AlloSure®, CareDx, Inc.] between 2/1/22-8/30/22 (N=33 patients, n=38 ddcfDNA draws). ddcfDNA levels were analyzed by presence or absence of DSA or rejection on biopsy (ISHLT 2004 ≥1R or ≥pAMR1) within 7 days prior or 30 days after ddcfDNA collection. ddcfDNA levels were compared by patient age, time from transplant, and history of congenital heart disease (CHD) or homograft exposure. Median ddcfDNA levels were below the clinical limit of detection in the absence of DSA and rejection (n=18) and for DSA (n=7) or 1R (n=5) rejection alone, whereas HT patients with both DSA and rejection (DSA+R, n = 8) had significantly higher ddcfDNA (0.77%, p=0.005, Figure). Using an a priori threshold of 0.35%, ddcfDNA levels were frequently elevated only in DSA+R (88% vs. 6%, 15%, and 20%, respectively, p=0.0001) and could differentiate DSA from DSA+R with a sensitivity and specificity of >85%. ddcfDNA levels were higher in HT recipients with homograft (n=12, 0.46%, p=0.006), but did not differ by CHD, age, and time from transplant. Higher ddcfDNA levels were observed for DSA+R and homograft exposure, supporting findings in adults, but not DSA or rejection alone. A ddcfDNA cut off of 0.35% was able to effectively discriminate DSA+R from DSA alone. These suggest that temporal differences exist between ddcfDNA elevation, DSA detection, and myocardial lymphocytic infiltration. Larger, longitudinal pediatric HT cohorts may better characterize this temporal relationship and establish the prognostic utility for ddcfDNA in this population. [ABSTRACT FROM AUTHOR]

If magnetite is a common serpentinization product, centimetric, massive and pure magnetite veins are rarely observed in serpentinites. Unique example, in the Aït Ahmane ultramafic unit (Bou Azzer Neoproterozoic ophiolite, Anti-Atlas, Morocco) allows to assess the hydrothermal processes that prevailed at the ending Precambrian. In this study, rock magnetism, petrography, mineral and bulk chemistry are combined to assess iron behavior in these meta-ultramafics, in order to constrain the serpentinites alteration and magnetite veins formation processes. Very high Cr#, low Mg#, high Fe 3+ # and low Ti content of Cr-spinels cores reflect a supra-subduction zone origin for the Aït Ahmane serpentinites precursor. Typical lizardite/chrysotile pseudomorphic texture in fresh serpentinites reveals an initial oceanic-like serpentinization, involving temperature <350 °C while the abundance of magnetite (up to 10.14 wt%) in these unaltered serpentinites attests of a relatively high serpentinization temperature >200 °C. Magnetic measurements reveal a lower magnetite content in hydrothermalized serpentinites hosting the magnetite veins, with lowest values (down to 0.58 wt%) for bleached serpentinites constituting the wall rock of the veins. These magnetic data are consistent with bulk rock chemistry showing a lower total iron content in hydrothermalized serpentinites. Hysteresis parameters and thermomagnetic measurements denote a magnetic grains size that increases with the alteration, associated with the emergence of a new magnetic phase (Cr-magnetite) produced by Cr-spinels alteration. A new proxy, based on thermomagnetic measurements, the CrM/M ratio, provides a quantification of its contribution to the magnetic susceptibility. Mineral chemistry allowed to identify the Cr-spinels alteration sequence and reveals an important chlorine enrichment in serpentine phases from hydrothermalized serpentinites. These results suggest that a Cl-rich acidic hydrothermal event involving temperatures below 350 °C produced an intense magnetite leaching in the host serpentinite and an advanced Cr-spinels alteration to ferritchromite and Cr-magnetite. Iron provided by this leaching have led to the formation of unique magnetite veins in the Aït Ahmane ultramafic unit. Two different settings are proposed for the hydrothermal event: (1) a continental hydrothermal system as advanced for the Co-Ni-As ores in the Bou Azzer inlier or (2) an oceanic black smoker type hydrothermal vent field on the Neoproterozoic seafloor. [ABSTRACT FROM AUTHOR]

Defensins protect human barriers from commensal and pathogenic microorganisms. Human α-defensin 6 (HD-6) is produced exclusively by small intestinal Paneth cells but, in contrast to other antimicrobial peptides (AMPs) for HD-6, no direct antibacterial killing activity has been detected so far. Herein, we systematically tested how environmental factors, like pH and reducing conditions, affect antimicrobial activity of different defensins against anaerobic bacteria of the human intestinal microbiota. Remarkably, by mimicking the intestinal milieu we detected for the first time antibacterial activity of HD-6. Activity was observed against anaerobic gut commensals but not against some pathogenic strains. Antibiotic activity was attributable to the reduced peptide and independent of free cysteines or a conserved histidine residue. Furthermore, the oxidoreductase thioredoxin, which is also expressed in Paneth cells, is able to reduce a truncated physiological variant of HD-6. Ultrastructural analyses revealed that reduced HD-6 causes disintegration of cytoplasmic structures and alterations in the bacterial cell envelope, while maintaining extracellular net-like structures. We conclude that HD-6 is an antimicrobial peptide. Our data suggest two distinct antimicrobial mechanisms by one peptide: HD-6 kills specific microbes depending on the local environmental conditions, whereas known microbial trapping by extracellular net structures is independent of the reducing milieu. [ABSTRACT FROM AUTHOR]

Résumé: L’obtention d’un résidu tumoral macroscopiquement nul doit être l’objectif du chirurgien gynécologue oncologue en cas de cancer annexiel. La cytoréduction complète peut nécessiter des résections étendues dans tous les secteurs de l’abdomen. Nous rapportons 2 cas rares de chirurgie macroscopiquement complète ayant nécessité des exérèses vasculaires iliaques avec remplacement prothétique. Nous discutons le choix stratégique de cette chirurgie à risque. [ABSTRACT FROM AUTHOR]

Abstract: Metrological studies and recent improvements in multi-collector thermal ionisation mass spectrometry (MC-TIMS) of uranium and plutonium in bulk nuclear material samples are presented with a focus on nuclear safeguards. Using total evaporation and modified total evaporation methods, experimental data are presented for isotope ratio measurements in routine mode spanning a range of almost ten orders of magnitude, with n(U-236)/n(U-238) measurements as low as a few parts per billion. Based upon these data, measurement reproducibility, associated measurement uncertainties with comparison to International Target Values (ITV), an upper limit of the instrumental uranium memory effect and of the hydride formation, and process and instrumental blank levels are examined. A comparison of measurement performance between the latest and previous generation of instruments for the total evaporation method is conducted. In addition, the implementation of a quality control procedure including control charts is presented and, in this context, commercially available U or Pu certified reference materials for isotope ratio and isotope dilution mass spectrometry are surveyed. The implementation of the Guide to the expression of Uncertainty in Measurement (GUM) is discussed for the modified total evaporation method. To address the importance of metrological traceability of measurement results to the SI units, the agreement between the certified values of two independently produced series of uranium certified reference materials (CRMs) – NBL and IRMM U series – is probed. Using IRMM CRMs as calibration standards, a new set of values for selected NBL U series CRMs is presented with expanded uncertainties of about 0.035% for major isotope ratios and at an order of magnitude of 0.1–0.5% for minor ratios. [Copyright &y& Elsevier]

Objective: This letter reports on the effect of enzyme replacement therapy with imiglucerase on bone healing and bone and blood abnormalities in a woman with previously untreated type 1 Gaucher disease (GD). Methods: The 49-year-old patient had been diagnosed with GD at the age of 28 years and had previously undergone splenectomy. She presented with pseudarthrosis 14 months after sustaining a traumatic fracture of the tibia and fibula. Therapy was begun with imiglucerase 60 U/kg q2wk. The effects of treatment on bone healing were monitored radiographically, and effects on blood and bone marrow biology were monitored by hemograms, myelograms, and hematopoietic and mesenchymal clonogenic assays. Results: Objective bone healing was observed starting in the third month of imiglucerase treatment. Blood abnormalities normalized and bone marrow parameters improved over the first 9 months, including a decrease in Gaucher cells, an increase in bone marrow CD34+ cell cloning efficiency, and the appearance of mesenchymal progenitors. Conclusion: This research letter reports the results of hematologic and bone evaluations during enzyme replacement therapy with imiglucerase in a woman with previously untreated type 1 GD who presented with a traumatic fracture. [ABSTRACT FROM AUTHOR]

Abstract: Objective: In a population-based case–control study examining the effects of postmenopausal hormone therapy (HT) on breast cancer risk, the authors conducted a validation study comparing prescription data from gynecologists with self-reports. Study Design and Setting: The study was conducted in the Rhein-Neckar and Hamburg regions of Germany from 2002 to 2005. A total of 224 cases and 225 controls, stratified by region, age, and hormone use were randomly selected for the validation study. Results: For ever/never use 88.2% agreement was seen, and agreement for ever/never use by type of HT was 80.6%, 80.3%, and 90.5% for mono-estrogen, cyclical combined, and continuous combined therapy, respectively. The intraclass correlation coefficient (ICC) for duration of use was high, 0.82 (95% confidence interval [CI]: 0.77, 0.85), as were the ICCs for age at first and last use, 0.88 (95% CI: 0.85, 0.91) and 0.98 (95% CI: 0.97, 0.98). Despite the exceptionally high number of different HT prescriptions available in Germany, comparison of exact brand name resulted in perfect agreement for 50.2% of participants, partial agreement for 29.3%, and no agreement for 20.7%. In general, agreement was not differential by disease status. Conclusion: Overall, the self-reported HT of the study participants corresponded well with physicians'' reports. [Copyright &y& Elsevier]

Abstract: A detector using liquid Xenon (LXe) in the scintillation mode is studied for Positron Emission Tomography (PET). The specific design aims at taking full advantage of the LXe. It does feature a promising solution insensitive to any parallax effect. This work reports on the spatial resolution capabilities of the first LXe prototype module, equipped with a Position Sensitive Photo-Multiplier Tube (PSPMT) operating in the VUV range (178nm). [Copyright &y& Elsevier]

Abstract: We present the first measurements of charge-dependent correlations on angular difference variables (pseudorapidity) and (azimuth) for primary charged hadrons with transverse momentum and from Au–Au collisions at . We observe correlation structures not predicted by theory but consistent with evolution of hadron emission geometry with increasing centrality from one-dimensional fragmentation of color strings along the beam direction to an at least two-dimensional hadronization geometry along the beam and azimuth directions of a hadron-opaque bulk medium. [Copyright &y& Elsevier]

Abstract: We review the most important experimental results from the first three years of nucleus–nucleus collision studies at RHIC, with emphasis on results from the STAR experiment, and we assess their interpretation and comparison to theory. The theory-experiment comparison suggests that central Au + Au collisions at RHIC produce dense, rapidly thermalizing matter characterized by: (1) initial energy densities above the critical values predicted by lattice QCD for establishment of a quark–gluon plasma (QGP); (2) nearly ideal fluid flow, marked by constituent interactions of very short mean free path, established most probably at a stage preceding hadron formation; and (3) opacity to jets. Many of the observations are consistent with models incorporating QGP formation in the early collision stages, and have not found ready explanation in a hadronic framework. However, the measurements themselves do not yet establish unequivocal evidence for a transition to this new form of matter. The theoretical treatment of the collision evolution, despite impressive successes, invokes a suite of distinct models, degrees of freedom and assumptions of as yet unknown quantitative consequence. We pose a set of important open questions, and suggest additional measurements, at least some of which should be addressed in order to establish a compelling basis to conclude definitively that thermalized, deconfined quark–gluon matter has been produced at RHIC. [Copyright &y& Elsevier]

Abstract: Identified mid-rapidity particle spectra of , , and from 200 GeV and collisions are reported. A time-of-flight detector based on multi-gap resistive plate chamber technology is used for particle identification. The particle-species dependence of the Cronin effect is observed to be significantly smaller than that at lower energies. The ratio of the nuclear modification factor () between protons () and charged hadrons (h) in the transverse momentum range is measured to be in minimum-bias collisions and shows little centrality dependence. The yield ratio of in minimum-bias collisions is found to be a factor of 2 lower than that in collisions, indicating that the Cronin effect alone is not enough to account for the relative baryon enhancement observed in heavy ion collisions at RHIC. [Copyright &y& Elsevier]

Abstract: We report the STAR measurement of ϕ meson production in and collisions at . Using the event mixing technique, the ϕ spectra and yields are obtained at mid-rapidity for five centrality bins in collisions and for non-singly-diffractive collisions. It is found that the ϕ transverse momentum distributions from collisions are better fitted with a single-exponential while the spectrum is better described by a double-exponential distribution. The measured nuclear modification factors indicate that ϕ production in central collisions is suppressed relative to peripheral collisions when scaled by the number of binary collisions . The systematics of versus centrality and the constant ratio versus beam species, centrality, and collision energy rule out kaon coalescence as the dominant mechanism for ϕ production. [Copyright &y& Elsevier]