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Introduction: Common Mental Disorders (CMD) are distress conditions which manifest themselves with anxiety, somatic, and depressive symptoms. CMD are highly prevalent in Indonesia especially among adolescents. Adolescent girls have a higher risk to develop CMD than boys. This may be related to anaemia and/or early onset of menstruation. This study aimed to determine the association between haemoglobin concentration and other determinants of CMD among adolescent girls in Indonesia. Methods: Data of 1,052 adolescent girls aged 15-19 years old from the Indonesian Basic Health Survey (Riskesdas) 2018 were analysed. CMD was measured using the Self Reporting Questionnaire (SRQ-20). Principal Component Analysis (PCA) of main determinants was applied and resulting principal components were investigated as risk factors for CMD. Results: The prevalence of CMD among adolescent girls aged 15-19 years in Indonesia was 16.5 percent. Of the 28·2 percent of adolescents with anaemia, 16·8 percent were suspected to have CMD. Three principal components were significantly associated with higher CMD score: 1) higher parental education, better employment of the father, and living in an urban area (β: 0·16, 95%-CI: 0·02; 0·30); 2) higher consumption of salty foods, high-fat foods, and soft drinks (β: 0·23, 95%-CI: 0·05; 0·40); and 3) having asthma, smoking, and a higher haemoglobin concentration (β: 1·74, 95%-CI: 1·59; 1·89). Conclusion: The strongest clustered determinants of CMD among adolescent girls in Indonesia were asthma, smoking status, and higher haemoglobin concentration, while age at menarche and anaemia were not related to CMD. Anaemia and earlier age at menarche were not associated with CMD. This study implies that adolescent girls with asthma and smoking cigarettes, as well as those having higher parental education and secured occupation, have an increased risk of developing mental disorders. Funding Statement: This study was performed as part of obtaining a PhD degree for which MA received a scholarship from Lembaga Pengelola Dana Pendidikan (LPDP), Republic of Indonesia. Declaration of Interests: All authors stated no conflict of interest. Ethics Approval Statement: All procedures were in accordance with the ethical standards issued by the Health Research Ethics Commission, Ministry of Health, Republic of Indonesia, and informed consent was obtained from all participants.

CAS; International audience; In two experiments performed with 20-30 MeV/u highly charged heavy ions (Pb56+, U91+) channeled through thin silicon crystals, we observed the original features of superdensity, associated to the glancing collisions with atomic rows undergone by part of the incident projectiles. In particular the very high collision rate yields a quite specific charge exchange regime, that leads to a higher ionization probability than in random conditions. X-ray measurements show that electrons captured in outershells are prevented from being stabilized, which enhances the lifetime of the projectile innershell vacancies. The charge state distributions and the energy loss spectra are compared to Monte-Carlo simulations. These simulations confirm, extend and illustrate the qualitative analysis of the experimental results.

International audience; High energy interaction of heavy ions with silicon integrated circuits contribute to transient events or single event effects (SEE) when ionizing the device along the particle path. Knowledge of the electron-hole pair density in the ion track is necessary for studying collected charge and estimating device reliability for deep sub-micron transistors. We have simulated ion-tracks in silicon with a Monte-Carlo code, TRAMOS, which is reported in this paper. High velocity heavy ion interactions with silicon are described within the plane wave Born approximation. For electrons, differential cross-sections are calculated using the phase shift method for elastic collisions and the BEB model for inelastic interactions. Calculations show that for high ion velocities, a non-negligible fraction of the energy is deposited outside the sensitive Volume of sub-micron transistors when compared to the case of the low ion velocities. The response of a silicon on insulator transistor to different ion tracks (size, density) is investigated with device simulations. Results show that for the 0.25 mu m gate length transistor simulated, due to the technology used, the size of the ion track has minor effect on the collected charge Q(c). For ions with same stopping power and different velocities, differences on Q(c) may show tip, due to recombination mechanisms. (c) 2005 Elsevier B.V. All rights reserved.

International audience; We report on the observation of a strong perturbation of the electron gas induced by 20 MeV/u U91+ ions and 13 MeV/u Pb81+ ions channeled in silicon crystals. This collective response (wake effect) induces a shift of the continuum energy level by more than 100 eV, which is observed by means of radiative electron capture into the K- and L-shells of the projectiles. We also observe an increase of the REC probability by 20–50% relative to the probability in a non-perturbed electron gas. The energy shift is in agreement with calculations using the linear response theory, whereas the local electron density enhancement is much smaller than predicted by the same model. This shows that, for the small values of the adiabaticity parameter achieved in our experiments, the density fluctuations are not strongly localized in the vicinity of the heavy ions.

We present results of an experiment using decelerated U91+ ions, extracted from the GSI-ESR storage ring, and transmitted through a thin silicon crystal in channeling conditions. Charge state at emergence, secondary electron multiplicity and X-rays are measured simultaneously. These conditions allow to study the competition between mechanical electron capture (MEC) and radiative electron capture (REC) as a function of impact parameter. We observe that REC is the dominant charge exchange process for the best channeled ions, i.e. those travelling always far from the silicon target core electrons. For ions with high transverse energy, MEC into highly excited states is counterbalanced by enhanced ionization arising from a succession of close collisions along atomic rows.

We present the physical principles underlying small angle multiple scattering of ions (MS) along with a renewed and comprehensive analytical approach to MS, based on probability theory, more precisely on stochastic processes. New theoretical results are derived, bearing in particular on the combination of angular and lateral spread. The scattering of ions by the screened target nuclei is governed by cross sections decreasing slowly with angle: large deflections may occur with probabilities high enough to render the basic characteristics of MS radically different from energy loss processes. These large deflections induce behaviour that may at first appear paradoxical. The width of the angular distributions presents a power law type dependence on thickness t of matter crossed, far from the familiar t1/2 behaviour: it varies as t1/ν, where the exponent ν increases from ≈0.4 for small t, but does not exceed ≈1.8 for large t. Mathematical concepts such as Levy flights and fractals are briefly discussed for a deeper insight into the nature of MS. The paper is intended to be self-contained, starting from first principles to present the basic elements of the physical and theoretical concepts required to describe MS processes. Projected angular distributions and the corresponding probability densities of the lateral spread of the trajectories with respect to the initial axis are calculated theoretically and numerically for a large range of thicknesses, as well as the statistical dependence between angular and lateral spread and the linear combination of their effects. The cases of both mono- and multielemental media, as well as that of thick targets are examined and the validity of the theory for projectiles heavier than the atoms of the medium and for ions with very high energies is discussed. Typical applications of MS theory are described, with particular emphasis on depth profiling of elements or isotopes in ion beam analysis. A large number of numerical data, including spatial and projected angular distribution with lateral spread calculations, are presented and are available electronically.

Resume Cette etude a pour objectif d'illustrer l'interet pour les controles externes de la qualite en biologie clinique d'evaluer non seulement les resultats quantitatifs mais egalement l'interpretation clinique qui en decoule. Elle a ete realisee au moyen des resultats obtenus pour la progesterone au cours du cycle 2000 des controles belges. Malgre la disponibilite de materiaux de reference certifies, la dispersion des resultats reste tres grande avec des coefficients de variation intra-groupes de plus de 30 % aux valeurs basses et de 10 a 20 % aux concentrations comprises entre 10 et 50 nmol/L. La dispersion des resultats quantitatifs aux valeurs basses est particulierement importante dans le groupe des utilisateurs Elecsys. La repartition de ces utilisateurs en deux sous-groupes utilisant une generation differente de kit met en evidence le probleme de sensibilite de l'un d'entre eux d'une part, et d'autre part, le risque d'erreur au niveau du diagnostic. Dans la zone des concentrations, dites quantifiables, subsiste egalement la problematique de la fixation des valeurs de references, illustree notamment par la grande heterogeneite des reponses pour les echantillons entre 5 et 15 nmol/L.

The biological action of swift ions decreases for increasing stopping power (LET), and the loss of efficiency is particularly high for heavy ions when the LET reaches its maximum value. In one of the models developed in the literature to account for this behavior, the biological action of light ions (and X rays) is attributed to clusters of energy deposition by low energy electrons. We have performed Monte-Carlo simulations to test this model for heavy and light ions (here uranium and helium ions). For helium ions, the experimental inactivation cross sections variations with LET are well reproduced when clusters with E⩾340 eV in spheres of radius R≈ 4.54 nm are considered, with an efficiency ≈4%, in very good agreement with the literature. However, these parameters cannot be applied to uranium ions (here 1.4 MeV/u U32+): the calculated number of clusters is ≈5 times larger than expected, a result which sets a limit to the cluster model.

First biological models of radiation action were based on the average energy deposited in the cell nucleus. Later theories have stressed the importance of the energy deposition at the nanometer level. Clusters of ionizations generated by K-electron removal seem to be a highly efficient mechanism for the induction of cell inactivation by heavy ions. Calculations and experimental results reported here support this hypothesis.

We have studied the location of Pb atoms on Cu(100) at submonolayer coverages using a few hundred keV He+ ion beams in channeling experiments under single- and double-alignment geometry. Different shadowing effects of Pb on Cu are experimentally observed according to the structure of the deposit, which was evidenced by LEED (in particular the c(5√2 × √2)R45° and c(2 × 2) structures). These effects disappear around the melting temperature of the structures. For a Pb coverage of θ ≈ 0.5, when a c(2 × 2) structure is formed, the distance dPb between the Pb plane and the first (100) Cu plane, measured under double alignment geometry (channeling along [100], blocking along [110] 45° off the normal to the surface), is dPb = 2.05 ± 0.05 A. We also find that the Pb atoms induce a static disorder in the first Cu surface plane. This disorder may be described by isotropic Gaussian displacements of Cu atoms, with a one-dimensional projected RMS deviation ud of around 0.12 A. It depends little on the Pb structure: in particular, there is no specific disordering in the alloyed state corresponding to low Pb coverages. From this observation, we deduce that for low coverage, the Pb atoms lie about 1 A above the first Cu plane.

The structural consequences of carbon incorporation into silicon and Si Ge layers deposited on silicon (100) by rapid thermal chemical vapor deposition have been studied. High resolution X-ray diffraction (HRXRD) analysis, channeling Rutherford backscattering spectroscopy (RBS), Raman spectroscopy and high resolution transmission electron microscopy (HRTEM) have been used to discover the structural particuliarities of this material in relation to the temperature of deposition. Experimental elastic energy density measurements have been compared with theoretical predictions for germanium concentrations of 0%, 10% and 16% as a function of substitutional carbon content. Raman spectroscopy measurements compared with an original high resolution transmission electron microscopy treatment showed that local compressive and tensile zones can simultaneously coexist at the interface. These localized tensile zones could probably act as pinning centers, blocking the propagation of dislocations, and hence increasing the critical thicknesses. With unadapted growth conditions, carbon segregation can occur. This effect can enhance local strain variations.

Matrix metalloproteinases (matrixins) constitute a group of extracellular proteinases belonging to the metzincin superfamily. They are involved in both physiological and pathological tissue remodeling processes, including those associated with cancer progression. Stromelysin-3, which is expressed in most invasive human carcinomas, is a matrix metalloproteinase with unusual functional properties. In particular, its mature form does not cleave any of the major extracellular matrix components. To define critical structural determinants involved in controlling stromelysin-3 proteolytic activity, we have used site-directed mutagenesis. We show that the deletion of at least 175 C-terminal amino-acids is sufficient to endow mouse stromelysin-3 with activities against casein, laminin, and type IV collagen. In the case of the human enzyme, however, a further and single Ala-235 Pro substitution is necessary to observe similar activities. Ala-235, which characterizes human stromelysin-3 among matrixins, is located immediately after the C terminus of the “Met-turn,” which forms a hydrophobic basis for the catalytic zinc atom in the metzincin family. We conclude that human stromelysin-3 has gained specific functional properties during evolution by amino acid substitution in the catalytic zinc environment, and that it represents an attractive target for specific inhibitors that may be used to prevent cancer progression.

Atomic relaxations on Cu(100) and stepped Cu(410) and (510) surfaces were measured using a few hundred keV He+ ions in channeling and double alignment geometries. On stepped surfaces, we have also attempted to determine the specific relaxation of edge atoms (both the components parallel and perpendicular to the (100) terraces). For this purpose, we have analyzed blocking effects on particles backscattered near θlab = 90°, around directions parallel to various major crystallographic axes of the terraces, the incident beam being aligned along the [100] axis perpendicular to the terraces. The studies were performed on clean and on oxygen covered surfaces. On (100) flat surfaces, we find a small contraction of the surface plane on clean Cu (about 2% of the bulk interplanar spacing), and a marked expansion (about 10%) on oxygen covered Cu (at saturation coverage, whose value was measured by nuclear reaction analysis). On stepped surfaces, it appears difficult to discriminate between the specific relaxation of the [001] edge row perpendicular to the terraces and the relaxation of the other [001] rows inside the terraces. Concerning the component of the [001] edge row relaxation in the terrace plane, our results provide an unambiguous estimate: we find a small contraction (about 0.04 A) on bare Cu and a larger expansion (about 0.18 A) under oxygen coverage. In all cases, we observed that the presence of oxygen induces a definite surface disordering which can be described as random small atomic displacements of Cu surface atoms around their mean position (on the order of 0.1 A). The results obtained on the (100) surface covered with oxygen can be interpreted in terms of a missing row model which has been proposed by some authors. However, our data can also be fitted with no missing row. Similarly, on the oxygen covered (410) stepped surface the data interpretation does not require the assumption of a missing row, but the results are not inconsistent with a description of the terrace where the fourth or possibly the third [001] row, parallel to step edge, is missing and where the edge [001] row suffers a considerable outward displacement in the terrace plane (≈ 0.3 A). The limits of high energy ion channeling for the measurement of surface atomic displacements, in particular when many sites are involved (for instance in the case of alternate relaxation) are discussed and illustrated.

In VLSI technology it is usual to proceed the ion implantation of heavy dopan species through very thin silicon dioxide gate insulators. As a consequence of this process there is a degradation of the insulating properties of the oxide which induces an enhanced leakage current in the MOS structures as well as a decrease of the dielectric breakdown voltage. In the present work we study quantitatively the possible physico-chemical causes of these degradation phenomena and of their recovery by thermal annealing using 18O isotopic tracing techniques. Films of Si18O2 with thicknesses ranging from 4 to 12 nm thermally grown on (100) Si wafers implanted with As and Sb in the fluences range 1014 −1016 cm−2. Using nuclear reaction analyses, secondary ions mass spectrometry, nuclear resonance profiling and channeling of α-particles with detection at grazing angles we measured the amount of oxygen lost from the silicon dioxide films due to sputtering at the oxide-vacuum interface, the amount of oxygen from the oxide film recoil-implanted into silicon, the amount of oxygen from the residual gas in the vacuum of the implantation chamber recoil-implanted into the silicon oxide, and the change in the stoichiometry of the silicon oxide films due to through-oxide implantation. The results of the present work together with the results existing in the literature on the electrical characterization of the same systems are used to discuss the possible physico-chemical causes of the observed dielectric loss. The recovery of the stoichiometry of the oxide films by thermal annealing in oxygen atmospheres after implantation was accomplished and the conditions to do it are also discussed.

Two aspects of heavy ion channeling are presented. The first aspect is related to the fact that channeled ions interact only with the most loosely bound target electrons. One can take benefit of this feature to study processes such as radiative electron capture (REC) and resonant transfer and excitation (RTE) in a dense quasi-free electron gas. The experimental work, performed at GANIL, devoted to these two processes is described. A possible extension to Nuclear RTE or NEEC (nuclear excitation by electron capture) studies is also described. The second aspect discussed is related to the periodicity of the potential experienced by channeled ions. We show that in a well chosen case this could lead to a significant and detectable coherent excitation of the projectile nucleus.

For both fundamental reasons and potential applications, the process of K-excitation by heavy ions at intermediate velocity has been re-investigated experimentally and theoretically and the main results are described here. The nature and the origin of the so-called “saturation effect” at high exciting charge is not yet elucidated. The importance of K-excitation is outlined in connection with problems of radiation damage.

Considerable improvement in depth resolution may be gained in depth profiling with nuclear resonances through the depth magnification associated to grazing incidence geometry. However, the random lateral displacement induced by angular multiple scattering processes in the medium leads to fluctuations of the trajectory lengths of the ions reaching a given depth. Negligible in perpendicular geometry, this effect induces a loss of depth resolution that deteriorates with the axial trajectory length with a speed increasing with tilt angle. The calculation of this effect is presented and illustrated theoretically and experimentally by the case of the narrow resonance at 151 keV in 18 O(p, α) 15 N. Projected lateral displacement distributions were calculated in monoatomic and biatomic media and converted to energy loss fluctuation distributions. The results show that while at depths of the order of 100 A the classical stochastic energy loss theory implemented with the PC program SPACES still applies, beyond a given depth multiple scattering induced effects increase sharply, widening the resolution functions and inducing long tails, so that the use of too large tilt angles becomes detrimental.

An investment strategy can combine different styles or signals. The simplest approach for combining these signals consists in using a weighting system that does not change over time. However, significant regime switches are not taken into account. This article shows that a dynamic signal weighting approach adds significant value compared to the static approach under specific conditions. First of all, it is necessary to significantly discriminate the performance of signals in different contexts. But interestingly, this is not a sufficient condition. The correlation between signal performances also matters. An analysis of the diversification benefits provided by each signal is necessary before deciding whether to adopt a dynamic signal weighting approach.

To allow subsequent genetically mediated fusion of foreign antigens to cholera toxin B subunit (CTB), two mutated CTB encoding genes (ctxB) were constructed and overexpressed in Escherichia coli. The signal peptide coding sequence was deleted and restriction sites were created at both ends of the modified sequence. Both synthesized CTBs contain additional amino acid(s) at the N terminus (one and three). They were purified as insoluble products and refolded into the natural pentameric CTB structure by a denaturation-renaturation cycle. After renaturation, both recombinant proteins recovered CTB antigenicity and the ability to bind to GM1 gangliosides, as shown by in vitro analysis. Preliminary data indicated that both properties were unaltered by fusion of a foreign peptide to the mutated CTBs.

This article describes an economy in which different types of workers form matches with different types of firms. Since at a given human capital level the expected wage will rise with the firm's technological level, the agents are going to compete for the most productive firms. On the other side, firms prefer to engage the most skilled workers. Then, the competition among agents is going to concern the level of human capital reached. Thus, not only the absolute level of human capital matters, but also the comparative level. In this context, the average human capital grows with the intensity of the competition for available jobs and the income distribution appears as an essential determinant of the intensity of this competition.