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Here, from macrophylogeographic mtDNA empirical data, we propose a scenario for the evolution and speciation of two important forest trees, European black pine and Scotch pine, and their multiple subspecies and varieties. Molecular clock simulations revealed that INDEL variability in the Pinus mitochondrial genome is relatively old, i.e., from the Pliocene-Miocene epoch, and related to historical tectonic continental fluctuations rather than to climate change at a large geographic scale. For conservation and management biodiversity program recommendations, special attention is given to the relationships between different speciation models, historical migration patterns, and differences between peripheral and central populations. Species evolution involves the mixing of different speciation modes, and every speciation mode has different effects on different DNA types (e.g., mitochondrial vs. chloroplast vs. nuclear DNA). The misbalance between the contributions of different meta-population census sizes vs. effective population sizes to asymmetric migration patterns is the result of different genotypes (and subphylogenetic lines) responding to selection pressure and adaptive evolution. We propose initial minimal size of conservation unit (between 3 and 5 ha) from central and marginal natural area of distribution for both species in the dynamic management system for practical forest genetic diversity management. The proposed physical sizes were determined by the effective population size, effective radius of seed distribution data, forest density age dynamics, succession pattern, natural selection pressing and species biology [R-17]. [ABSTRACT FROM AUTHOR]

The roles GABAergic and glutamatergic inputs in regulating the activity of the gonadotrophin‐releasing hormone (GnRH) neurons at the time of the preovulatory surge remain unclear. We used expansion microscopy to compare the density of GABAergic and glutamatergic synapses on the GnRH neuron cell body and proximal dendrite in dioestrous and pro‐oestrous female mice. An evaluation of all synapses immunoreactive for synaptophysin revealed that the highest density of inputs to rostral preoptic area GnRH neurons occurred within the first 45 µm of the primary dendrite (approximately 0.19 synapses µm‐1) with relatively few synapses on the GnRH neuron soma or beyond 45 µm of the dendrite (0.05‐0.08 synapses µm‐1). Triple immunofluorescence labelling demonstrated a predominance of glutamatergic signalling with twice as many vesicular glutamate transporter 2 synapses detected compared to vesicular GABA transporter. Co‐labelling with the GABAA receptor scaffold protein gephyrin and the glutamate receptor postsynaptic density marker Homer1 confirmed these observations, as well as the different spatial distribution of GABA and glutamate inputs along the dendrite. Quantitative assessments revealed no differences in synaptophysin, GABA or glutamate synapses at the proximal dendrite and soma of GnRH neurons between dioestrous and pro‐oestrous mice. Taken together, these studies demonstrate that the GnRH neuron receives twice as many glutamatergic synapses compared to GABAergic synapses and that these inputs preferentially target the first 45 µm of the GnRH neuron proximal dendrite. These inputs appear to be structurally stable before the onset of pro‐oestrous GnRH surge. [ABSTRACT FROM AUTHOR]

The superposition of the quantum rotational motion (tunneling) of the encapsulated Sc2C2 complex with the classical rotational motion of the surrounding C84 molecule in a powder crystal of Sc2C2@C84 fullerite is investigated by theory. Since the quantum rotor is dragged along by the C84 molecule, any detection method which couples to the quantum rotor (in casu the C2 bond of the Sc2C2 complex) also probes the thermally excited classical motion (uniaxial rotational diffusion and stochastic meroaxial jumps) of the surrounding fullerene. The dynamic rotation-rotation response functions in frequency space are obtained as convolutions of quantum and classical dynamic correlation functions. The corresponding Raman scattering laws are derived, and the overall shape of the spectra and the width of the resonance lines are studied as functions of temperature. The results of the theory are confronted with experimental low-frequency Raman spectra on powder crystals of Sc2C2@C84 [M. Krause et al., Phys. Rev. Lett. 93, 137403 (2004)]. The agreement of theory with experiment is very satisfactory in a broad temperature range. [ABSTRACT FROM AUTHOR]

Superexchange interactions in alkali fullerides AC60 are derived for C60 molecular ions separated by interstitial alkali-metal ions. We use a multiconfiguration approach which comprises the lowest molecular orbital states of the C60 molecule and the excited s and d states of the alkali-metal atom A. Interactions are described by the valence bond (Heitler–London) method for a complex (C60–A–C60)– with two valence electrons. The electronic charge transfer between the alkali-metal atom and a neighboring C60 molecule is not complete. The occupation probability of excited d and s states of the alkali atom is not negligible. In correspondence with the relative positions of the C60 molecules and A atoms in the polymer crystal, we consider 180° and 90° (angle) superexchange pathways. For the former case the ground state is found to be a spin singlet separated from a triplet at ∼20 K. For T<20 K there appear strong spin correlations for the 180° superexchange pathway. The results are related to spin lattice relaxation experiments on CsC60 in the polymerized and in the quenched cubic phase. [ABSTRACT FROM AUTHOR]

Starting from a multipole expansion of intramolecular Coulomb interactions, we present configuration interaction calculations of the molecular energy terms of the hole configurations n (h[sup +][sub u])[sup m], m =2-5, of C[sup m][sub 60] cations, of the electron configurations t[sup n][sub 1u], n = 2 - 4, of the C[sup n-][sub 60] anions, and of the exciton configurations(h[sup +][sub u], t[sup -][sub 1u]), (h[sup +][sub u] t[sup -][sub 1g]) of the neutral C[sub 60] molecule. The ground state of C²sub 60]- is either ³T[sub 1g] or ¹A[sub g], depending on the energy separation between t[sub 1g] and t[sub 1u] levels. There are three close (∼0.03 eV) low lying spin triplets ³T[sub 1g], ³G[sub g], ³T[sub 2g] for C[sup 2+][sub 60] , and three spin quartets [sup 4]T[sub 1u], [sup 4]G[sub u], [sup 4]T[sub 2u] for C[sup 3+][sub 60], which can be subjected to the Jahn-Teller effect. The number of low lying nearly degenerate states is largest for m = 3 holes. We have calculated the magnetic moments of the hole and electron configurations and found that they are independent of molecular orientation with respect to an external magnetic field. The coupling of spin and orbital momenta differs from the atomic case. We analyze the electronic dipolar transitions (t[sub 1u])²→ t[sub 1u]t[sub 1g] and (t[sub 1u])³→(t[sub 1u])2t[sub 1g] for C[sup 2-][sub 60] and C[sup 3-][sub 60]. Three optical absorption lines (3T[sub 1g]-³H[sub u], ³T[sub 1u], ³A[sub u]) are found for the ground level of C[sup 2-][sub 60] and only one line ([sup 4]A[sub u] → [sup 4]T[sub 1g]) for the ground state of C[sup 3-][sub 60]. We compare our results with the experimental data for C[sup n-]sub 60] in solutions and with earlier theoretical studies. [ABSTRACT FROM AUTHOR]

Starting from a model of rigid interacting C[sub 60] polymer chains on an orthorhombic lattice, we study the mutual orientation of the chains and the stability of the crystalline structures Pmnn and I2/m. We take into account (i) van der Waals interactions and electric quadrupole interactions between C[sub 60] monomers on different chains as well as (ii) interactions of the monomers with the surrounding alkali atoms. The direct interactions (i) always lead to an antiferrorotational structure Pmnn with alternate orientation of the C[sub 60] chains in planes (001). The interactions (ii) with the alkalis consist of two parts: translation-rotation (TR) coupling where the orientations of the chains interact with displacements of the alkalis, and quadrupolar electronic polarizability (ep) coupling, where the electric quadrupoles on the C[sub 60] monomers interact with induced quadrupoles due to excited electronic d-states of the alkalis. Both interactions (ii) lead to an effective orientation-orientation interaction between the C[sub 60] chains and always favor the ferrorotational structure I2/m, where C[sub 60] chains have a same orientation. The structures Pmnn for KC[sub 60] and I2/m for Rb- and C[sub s]C[sub 60] are the result of a competition between the direct interaction (i) and the alkali-mediated interactions (ii). In Rb- and C[sub s]C[sub 60] the latter are found to be dominant, the preponderant role being played by the quadrupolar electronic polarizability of the alkali ions. [ABSTRACT FROM AUTHOR]

A model of the intermolecular potential in solid C60, which is based on Born–Mayer repulsions, van der Waals attractions, and electrostatic multipoles, is presented. The potential is expanded in terms of multipolar rotator functions. The orientation–orientation interaction and the crystal field are calculated. The orientational phase transition to the Pa3 phase is studied with the methods of statistical mechanics. The discontinuity of the order parameter at the transition and the temperature evolution of the order parameter are calculated. The lattice contraction at the phase transition is evaluated. The influence of the lattice contraction on the crystal field and on the orientational order is studied. [ABSTRACT FROM AUTHOR]

A microscopic theory, which describes the orientational dynamics of C60 molecules in the face-centered cubic phase of C60-fullerite, is formulated for the case of a complex molecular structure. Interaction centers which comprise atoms, double bonds, and single bonds as molecular constituents contribute to the intermolecular potential. Orientation dependent physical properties are described in terms of symmetry-adapted rotator functions. It is found that a same set of rotator functions is sufficient even in the case of a complex molecular structure. Phase transition temperatures are discussed for various models of molecular structure. [ABSTRACT FROM AUTHOR]

Dynamic equations of coupled translational and rotational motions in orientationally disordered crystals are derived within a microscopic theory. Beside a bilinear coupling, cubic terms are taken into account in the interaction potential of translation–rotation coupled modes. Transport coefficients for rotational and translation motion are calculated by mode–mode coupling theory. The orientational motion is not restricted to relaxation behavior. [ABSTRACT FROM AUTHOR]

Abstract: Background: Antineuronal antibodies can be associated with both gastrointestinal (GI) and brain disorders. For example, antibodies against the potassium channel subunit dipeptidyl‐peptidase‐like protein‐6 (DPPX) bind to neurons in the central nervous system (CNS) and myenteric plexus and cause encephalitis, commonly preceded by severe unspecific GI symptoms. We therefore investigated the prevalence of antineuronal antibodies indicative of treatable autoimmune CNS etiologies in GI patients. Methods: Serum samples of 107 patients (Crohn's disease n = 42, ulcerative colitis n = 16, irritable bowel syndrome n = 13, others n = 36) and 44 healthy controls were screened for anti‐DPPX and further antineuronal antibodies using immunofluorescence on rat brain and intestine and cell‐based assays. Functional effects of high‐titer reactive sera were assessed in organ bath and Ussing chamber experiments and compared to non‐reactive patient sera. Key Results: Twenty‐one of 107 patients (19.6%) had antibodies against the enteric nervous system, and 22 (20.6%) had anti‐CNS antibodies, thus significantly exceeding frequencies in healthy controls (4.5% each). Screening on cell‐based assays excluded established antienteric antibodies. Antibody‐positive sera were not associated with motility effects in organ bath experiments. However, they induced significant, tetrodotoxin (TTX)‐insensitive secretion in Ussing chambers compared to antibody‐negative sera. Conclusions & Inferences: Antineuronal antibodies were significantly more frequent in GI patients and associated with functional effects on bowel secretion. Future studies will determine whether such antibodies indicate patients who might benefit from additional antibody‐directed therapies. However, well‐characterized encephalitis‐related autoantibodies such as against DPPX were not detected, underlining their rarity in routine cohorts. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) remains one of the most threatening diseases and Nigeria has one of the world’s largest burdens. This study performed high-throughput spoligotyping directly on sputum smears to describe the Mycobacterium tuberculosis strains circulating among new TB patients in Nigeria. Methods: All State TB control programmes in Nigeria were requested to submit 25–50 smear-positive Ziehl-Neelsen (ZN) stained slides for screening during 2013–2014. DNA was extracted from 929 slides for spoligotyping and drug-resistance analysis using microbead-based flow-cytometry suspension arrays. Results: Spoligotyping results were obtained for 549 (59.1%) of 929 samples. Lineage 4 Cameroon sublineage (L4.6.2) represented half of the patterns, Mycobacterium africanum (L5 and L6) represented one fifth of the patterns, and all other lineages, including other L4 sublineages, represented one third of the patterns. Sublineage L4.6.2 was mostly identified in the north of the country whereas L5 was mostly observed in the south and L6 was scattered. The spatial distribution of genotypes had genetic geographic gradients. We did not obtain results enabling the detection of drug-resistance mutations. Conclusion/Significance: We present the first national snapshot of the M. tuberculosis spoligotypes circulating in Nigeria based on ZN slides. Spoligotyping data can be obtained in a rapid and high-throughput manner with DNA extracted from ZN-stained slides, which may potentially improve our understanding of the genetic epidemiology of TB. [ABSTRACT FROM AUTHOR]

Interrogation of art materials with light reveals valuable information about their composition and properties for the art conservator. Raman and mid-IR FTIR spectroscopy are non-destructive methods that probe vibrational behaviour and can rapidly and non-invasively characterise the media and pigments in paints. Time-resolved UV-Vis spectroscopy can yield important information about the dynamics of photodegradation. This article highlights some examples of how time-resolved UV-Vis, Raman and FTIR spectroscopy have assisted art conservators in New Zealand and helped to determine appropriate treatment methods and preventative conservation strategies. [ABSTRACT FROM AUTHOR]

We present the latest results of our ongoing multiplicity study of (Community) TESS Objects of Interest, using astrometric and photometric data from the ESA‐Gaia mission to detect stellar companions of these stars and characterize their properties. A total of 134 binary, 6 hierarchical triple, and two quadruple star systems are identified among 1106 targets whose multiplicity is investigated in the course of our survey, located at distances closer than about 500 pc around the Sun. The detected companions and targets are at the same distance and have a common proper motion, as expected for components of gravitationally bound stellar systems, as demonstrated by their accurate Gaia DR3 astrometry. The companions have masses from about 0.11 to 2 M⊙$$ {M}_{\odot } $$ and are most abundant in the mass range between 0.2 and 0.5 M⊙$$ {M}_{\odot } $$. The companions have projected separations from the targets between about 50 and 9700 au. Their frequency is the highest and constant from about 300 up to 750 au, decreasing at larger projected separations. In addition to main sequence stars, four white dwarf companions are detected in this study, whose true nature is revealed by their photometric properties. [ABSTRACT FROM AUTHOR]

Solid-phase single antigen bead ( SAB) assays are standard of care for detection and identification of donor-specific antibody ( DSA) in patients who receive solid organ transplantation ( SOT). While several studies have documented the reproducibility and sensitivity of SAB testing for DSA, there are little data available concerning its specificity. This study describes the identification of antibodies to β2-microglobulin-free human leukocyte antigen (β2-m- fHLA) heavy chains on SAB arrays and provides a reassessment of the clinical relevance of DSA testing by this platform. Post-transplant sera from 55 patients who were positive for de novo donor-specific antibodies on a SAB solid-phase immunoassay were tested under denaturing conditions in order to identify antibodies reactive with β2-m- fHLA or native HLA ( nHLA). Antibodies to β2-m- fHLA were present in nearly half of patients being monitored in the post-transplant period. The frequency of antibodies to β2-m- fHLA was similar among DSA and HLA antigens that were irrelevant to the transplant (non- DSA). Among the seven patients with clinical or pathologic antibody-mediated rejection (AMR), none had antibodies to β2-m- fHLA exclusively; thus, the clinical relevance of β2-m- fHLA is unclear. Our data suggests that SAB testing produces false positive reactions due to the presence of β2-m- fHLA and these can lead to inappropriate assignment of unacceptable antigens during transplant listing and possibly inaccurate identification of DSA in the post-transplant period. [ABSTRACT FROM AUTHOR]

The thermal expansion [ABSTRACT FROM AUTHOR]

Anharmonic effects in an atomic monolayer thin crystal with honeycomb lattice structure are investigated by analytical and numerical lattice dynamical methods. Starting from a semiempirical model for anharmonic couplings of third and fourth orders, we study the in-plane and out-of-plane (flexural) mode components of the generalized wave vector dependent Grtineisen parameters, the thermal tension and the thermal expansion coefficients as a function of temperature and crystal size. From the resonances of the displacement-displacement correlation functions, we obtain the renormalization and decay rate of in-plane and flexural phonons as a function of temperature, wave vector, and crystal size in the classical and in the quantum regime. Quantitative results are presented for graphene. There, we find that the transition temperature Tα from negative to positive thermal expansion is lowered with smaller system size. Renormalization of the flexural mode has the opposite effect and leads to values of Tα ≈ 300 K for systems of macroscopic size. Extensive numerical analysis throughout the Brillouin zone explores various decay and scattering channels. The relative importance of normal and umklapp processes is investigated. The work is complementary to crystalline membrane theory and computational studies of anharmonic effects in two-dimensional crystals. [ABSTRACT FROM AUTHOR]

Background: We aimed to investigate the molecular epidemiology of Mycobacterium tuberculosis complex (MTBC) isolates in the province of Palermo, Sicily, Italy, by characterizing 183 isolates identified in the years 2004–2012. A comparison with 104 MTBC strains identified in the same geographic area in the years 1994–2000 was also carried out. Methods: One hundred eighty-three MTBC isolates identified in Palermo, Italy, in the years 2004–2012 were analyzed by spoligotyping and the 24 mycobacterial interspersed repetitive unit (MIRU)-variable-number tandem-repeat (VNTR) method typing. Susceptibility testing to streptomycin, isoniazid, rifampin and ethambutol was also performed. Furthermore, the spoligotyping dataset obtained from 104 MTBC isolates identified from 1994 to 2000 was reanalyzed. Distribution into lineages and clustering of isolates in the two periods was compared. Results: One hundred seventy-seven out of the 183 isolates of MTBC submitted to molecular typing were fully characterized. Of these, 108 were from Italian-born and 69 from foreign-born individuals. Eleven different lineages and 35 families-subfamilies were identified with the most represented lineages being Haarlem (26.5%), T (19.2%), LAM (13.6%) and S (8.5%). Except for the Haarlem lineage, where isolates from foreign-born patients were overrepresented, the distribution of isolates in the families belonging to the Euro-American clone reflected the proportions of the two subpopulations. A total of 27 (15.2%) strains were clustered and three clusters were mixed. Approximately 25% of the 183 MTBC isolates under study proved to be resistant to at least one antiTB drug, with only three isolates categorized as multidrug resistant (MDR). When MTBC isolates identified in the years 1994–2000 were reanalyzed, lineages T (30.8%), LAM (29.8%), Haarlem (16.3%) and S (13.5%) proved to be predominant. No MTBC isolates belonging to CAM, U, CAS, Turkish and Ural lineages were identified. Conclusions: A wide heterogeneity was detected among the MTBC strains isolated in the years 2004–2012. Six lineages were not present among the isolates of the period 1994–2000. Comparison between distribution of lineages in the two consecutive periods depicts rapid and deep changes in the TB epidemiology in Palermo, Italy. An universal and continued laboratory-based surveillance of TB in Sicily is required. [ABSTRACT FROM AUTHOR]

Multi-Drug Resistant Tuberculosis (MDR-TB), i.e. bacilli resistant to rifampicin (RIF) and isoniazid (INH), is a major Public Health concern in Pakistan according to WHO estimates (3.5% and 32% of new and retreated cases, respectively). Previous Pakistanis reports identified a correlation between being MDR and belonging to Beijing or EAI lineages in one study, and belonging to “H4”-Ural Euro-American sublineage in another study. In addition, MDR-TB transmission was suspected in Karachi. We tested MDR characteristics on a Punjab sample of 278 clinical isolates (without selection for Multi-Drug Resistance) including new and retreated cases collected from 2008 to 2012. All samples were characterized by a new, microbead-based method named “TB-SPRINT” (molecular diagnostic including spoligotype identification, and genetic resistance determinants to first-line anti-TB drugs RIF and INH). Isolates from 2011 to 2012 ( n = 100) were further analyzed using 24-loci MIRU-VNTR. We detected 8.7% MDR isolates (CI 95% = [5.0; 12.5]), mainly among CAS lineage that predominates in this central-East region of Pakistan. Out of 20 MDR-TB cases, 12 different TB-SPRINT profiles were identified, limiting the suspicion of MDR-TB transmission. 24 MIRU-VNTR confirmed the unrelatedness of isolates with different TB-SPRINT profiles and discriminated 3 isolates with identical TB-SPRINT profiles. In conclusion, our study did not confirm any of the correlations between Multi-Drug Resistance and lineage or sublineage in Punjab, Pakistan. MDR-TB isolates were diverse indicating that transmission is not pervasive. TB-SPRINT proved useful as a first step for detecting MDR-TB likely transmission events, before more extensive genotyping such as 15 or 24 MIRU-VNTR and thorough epidemiological investigation. [ABSTRACT FROM AUTHOR]

Introduction Because the association of myocardial infarction (MI) and venous thromboembolism (VTE) is uncertain, we tested MI as a VTE risk factor and VTE as a predictor of MI. Materials and Methods Using Rochester Epidemiology Project resources, we identified all Olmsted County, MN residents with objectively-diagnosed incident VTE over the 13-year period, 1988-2000 (n = 1311), one to two resident controls per VTE case (n = 1511), and all residents with incident MI over the 31-year period, 1979-2010. For VTE cases and controls, we reviewed their complete medical records in the community for VTE and MI risk factors. Using conditional logistic regression we tested MI as a potential VTE risk factor, both unadjusted and after adjusting for VTE risk factors. We also followed VTE cases and controls without prior MI forward in time for incident MI through 12/31/2010, and using Cox proportional hazards modeling, tested VTE as a predictor of MI, both unadjusted and after adjusting for MI risk factors. Results The number (%) of MI prior to VTE among cases and controls were 75 (5.7) and 51 (3.4), respectively, and the number (%) of MI after VTE among cases and controls were 58 (4.4) and 77 (5.1), respectively. In univariate analyses, MI was significantly associated with VTE but not after adjusting for VTE risk factors. In both univariate and multivariate analyses, VTE (overall or idiopathic) was not a predictor of MI. Conclusions MI is not an independent risk factor for VTE, and VTE is not a predictor of MI. [ABSTRACT FROM AUTHOR]

Background Hyoscine butylbromide ( HBB, Buscopan®) is clinically used to treat intestinal cramps and visceral pain. Various studies, mainly on animal tissues, suggested that its antimuscarinic action is responsible for its spasmolytic effect. However, functional in vitro studies with human tissue have not been performed so far. Methods We wanted to provide a comprehensive study on the mode of action of HBB in human intestinal samples and investigated HBB (1 nmol L−1-10 μmol L−1) effects on muscle activity with isometric force transducers and calcium imaging, on epithelial secretion with Ussing chamber technique and on enteric neurons using fast neuroimaging. Key Results Hyoscine butylbromide concentration dependently reduced muscle contractions, calcium mobilization, and epithelial secretion induced by the muscarinic agonist bethanechol with IC50 values of 429, 121, and 224 nmol L−1, respectively. Forskolin-induced secretion was not altered by HBB. Cholinergic muscarinic muscle and epithelial responses evoked by electrical nerve stimulation were inhibited by 1-10 μmol L−1 HBB. Moreover, HBB significantly reduced the bethanechol-induced action potential discharge in enteric neurons. Interestingly, we observed that high concentrations of HBB (10 μmol L−1) moderately decreased nicotinic receptor-mediated secretion, motility, and nerve activity. Conclusions & Inferences The results demonstrated the strong antimuscarinic action of HBB whereas the nicotinic antagonism at higher concentrations plays at most a moderate modulatory role. The muscle relaxing effect of HBB and its inhibition of muscarinic nerve activation likely explain its clinical use as an antispasmodic drug. Our results further highlight a so far unknown antisecretory action of HBB which warrants further clinical studies on its use in secretory disorders. [ABSTRACT FROM AUTHOR]

Information processing by neurons has been traditionally envisioned to occur in discrete neuronal compartments. Specifically, dendrites receive and integrate synaptic inputs while axons initiate and conduct spikes to distal neuronal targets. We report here in mice, using morphological reconstructions and electrophysiology, that the gonadotropin-releasing hormone (GnRH) neurons that control mamma-lian fertility do not conform to this stereotype and instead possess a single projection structure that functions simultaneously as an axon and dendrite. Specifically, we show that the GnRH neuron projection to the median eminence to control pituitary hormone secretion possesses a spike initiation site and conducts action potentials while also exhibiting spines and synaptic appositions along its entire length. Classical axonal or dendritic markers are not detectable in the projection process. Activation of ionotropic glutamate and/or GABA receptors along the GnRH neuron projection is capable of depolarizing the membrane potential and initiating action potentials. In addition, focal glutamate application to the projection is able to regulate the width of propagating spikes. These data demonstrate that GnRH neurons elaborate a previously uncharacterized neuronal projection that functions simultaneously as an axon and dendrite. This structure, termed a "dendron," greatly expands the dynamic control of GnRH secretion into the pituitary portal system to regulate fertility. [ABSTRACT FROM AUTHOR]

We demonstrate a simple route toversatile electrically addressableconductive polymer graft copolymer systems. The monomer of poly(3,4-ethylenedioxythiophene),one of the commercially most important conductive polymers, was modifiedby the addition of an ATRP-initiating site to grow brushes from. Themodified monomer is easily accessible by a one-step synthesis fromthe commercially available 2,3-dihydrothieno[3,4-b][1,4]dioxin-2-yl)methanol. The modified monomer is subsequentlyelectropolymerized onto large area gold-coated electrodes and utilizedas a backbone for grafting pH-responsive poly(acrylic acid) brushesfrom. [ABSTRACT FROM AUTHOR]

The determination of the layer number ${\cal N}$ in nanoscale thin layered crystals is a challenging problem of technological relevance. In addition to innovative experimental techniques, a thorough knowledge of the underlying lattice dynamics is required. Starting from phenomenological atomic interaction potentials we have carried out an analytical study of the low-frequency optical phonon dispersions in layered crystals. At the gamma point of the two-dimensional Brillouin zone the optical phonon frequencies correspond to rigid-plane shearing and compression modes. We have investigated graphene multilayers (GML) and hexagonal boron-nitride multilayers (BNML). The frequencies show a characteristic dependence on ${\cal N}$. The results which are represented in the form of fan diagrams are very similar for both materials. Due to charge neutrality within layers Coulomb forces play no role, only van der Waals forces between nearest neighbor layers are relevant. The theoretical results agree with recent low-frequency Raman results on rigid-layer modes [Tan et al., Nature Mater. 11, 294 (2012)] in GML and double-resonant Raman scattering data on rigid-layer compression modes [Herziger et al., Phys. Rev. B 85, 235447 (2012)] in GML. [ABSTRACT FROM AUTHOR]

The lattice dynamics of low-frequency rigid-plane modes in metallic (graphene multilayers, GML) and in insulating (hexagonal boron-nitride multilayers, BNML) layered crystals is investigated. The frequencies of shearing and compression (stretching) modes depend on the layer number N and are presented in the form of fan diagrams. The results for GML and BNML are very similar. In both cases, only the interactions (van der Waals and Coulomb) between nearest-neighbor planes are effective, while the interactions between more distant planes are screened. A comparison with recent Raman scattering results on low-frequency shear modes in GML [Tan et al., Nat. Mater., in press, doi: 10.1038/nmat3245, (2012)] is made. Relations with the low-lying rigid-plane phonon dispersions in the bulk materials are established. Master curves, which connect the fan diagram frequencies for any given N. are derived. Static and dynamic thermal correlation functions for rigid-layer shear and compression modes are calculated. The results might be of use for the interpretation of friction force experiments on multilayer crystals. [ABSTRACT FROM AUTHOR]

Non-technical summary Imaging of slow, long-lasting changes in intracellular Ca2+ levels ([Ca2+]i) is a common method to assess neuronal activity. We found that fast [Ca2+]i imaging (≥200 Hz sampling rate) may be a new option to record fast neuronal events including spike discharge and fast synaptic transmission in enteric neurones. These [Ca2+]i peaks required opening of voltage-gated sodium and calcium channels as well as Ca2+ release from intracellular stores. [ABSTRACT FROM AUTHOR]

A unified theory of phonon dispersions and piezoelectricity in bulk and multilayers of hexagonal boron nitride (h-BN) is derived. The dynamical matrix is calculated on the basis of an empirical force constant model of intralayer valence and interlayer van der Waals interactions. Coulomb interactions are calculated by Ewald's method, adapted for the three-dimensional (3D) and the multilayer case. The deformation of the ionic charge distribution with long-wave lattice displacements is taken into account. Special attention is devoted to the nonanalytic long-range Coulomb contribution to the dynamical matrix which is different for the 3D crystal and the multilayer case. Consequently there is a splitting of the transverse optical (TO) and longitudinal optical (LO) phonon branches of E1u symmetry and a discontinuity of the A2u branch at the Γ point in 3D h-BN. No such splitting and discontinuity at Γ are present in multilayer crystals with a finite number N of layers. There a diverging bundle of N overbending optical phonon branches emerges from Γ. Born's long-wave theory is applied and extended for the study of piezoelectricity in layered crystals. While 3D h-BN and h-BN multilayers with an even number of layers (symmetry D6h) are not piezoelectric, multilayers with an uneven number of Nu layers (symmetry D3h) are piezoelectric; the piezoelectric coefficient e1,11 is inversely proportional to Nu. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Because the risk of venous thromboembolism (VTE) associated with progestin is uncertain, we tested oral contraceptives, estrogen and progestin as independent VTE risk factors. Materials and Methods: Using longitudinal, population-based Rochester Epidemiology Project resources, we identified all Olmsted County, MN women with objectively-diagnosed incident VTE over the 13-year period, 1988-2000 (n=726) and one to two Olmsted County women per case matched on age, event year and duration of prior medical history (n=830), and reviewed their complete medical history in the community for previously-identified VTE risk factors (i.e., hospitalization with or without surgery, nursing home confinement, trauma/fracture, leg paresis, active cancer, varicose veins and pregnancy/postpartum), and oral contraceptive, oral estrogen, and oral or injectable progestin exposure. Using conditional logistic regression we tested these hormone exposures as VTE risk factors, both unadjusted and after adjusting for previously-identified VTE risk factors. Results: In unadjusted models, oral contraceptives, progestin alone, and estrogen plus progestin were significantly associated with VTE. Individually adjusting for body mass index (BMI) and previously-identified VTE risk factors, these effects remained essentially unchanged except that progestin alone was not associated with VTE after adjusting for active cancer. Considering only case-control pairs without active cancer, progestin alone was positively but non-significantly associated with VTE (OR=2.49; p=0.16). Adjusting for BMI and previously-identified VTE risk factors including active cancer, oral contraceptives, estrogen alone, and progestin with or without estrogen were significantly associated with VTE. Conclusions: Oral contraceptives, estrogen alone, estrogen plus progestin, and progestin with or without estrogen are independent VTE risk factors. [Copyright &y& Elsevier]

Unmanned Aerial Vehicle (UAV) technology provides potential for very high spatial resolution (<25 cm) mapping of relatively large areas at a user-defined re-survey frequency. In a riparian context, UAV technology provides a mechanism for riparian managers to (a) quantify riparian terrain and vegetation units and (b) identify standing dead wood and canopy mortality. In this study a paraglider UAV was used to survey 174 ha at 6.8-21.8 cm ground resolution. Pixel-based and object-oriented classification approaches were used at the scale of a single image and a channel mosaic. Significant potential was demonstrated: vegetation units were classified with an accuracy of kappa = 0.79 and standing dead wood units were identified with an average accuracy with respect to omission and commission errors of 80% and 65%, respectively. Work across multiple images identified that major constraints currently result from factors such as illumination conditions and sensor movement during flight, which create variations in spatial resolution and radiometry. It is expected that with further methodological refinement and more complex methods of automated radiometric correction UAV technology can provide the flexibility to rapidly produce very high resolution map products to aid riparian management. [ABSTRACT FROM AUTHOR]

From the theory of many-electron states in atoms, we know that there exists a strong Coulomb repulsion, which results in the electronic term structure of atoms and is responsible for Hund’s rules. By expanding the Coulomb on-site repulsion into a multipolar series, we derive this interaction and show that it is also present in solids as a correlation effect, which means that the interaction requires a multideterminant version of the Hartree-Fock method. Of particular interest is the case where this interaction couples states of localized ( f) and delocalized ( s) electrons. We show that the interaction is bilinear in the creation/annihilation operators for localized electrons and bilinear in the operators for conduction electrons. To study the coupling, we consider a simple model in the framework of an effective limited configuration interaction method with one localized f-electron and one itinerant s-electron per crystal site. The on-site multipole interaction between the f- and s-electrons is explicitly taken into account. It is shown that depending on the low-lying excitation spectrum imposed by the crystal electric field, the model can lead not only to ferromagnetism but also to a nonmagnetic state. The model is relevant for solids with localized and itinerant electron states. [ABSTRACT FROM AUTHOR]

Background: The Ebola virus is transmitted by direct contact with bodily fluids of infected individuals, eliciting death rates as high as 90% among infected humans. Currently, replication defective adenovirus-based Ebola vaccine is being studied in a phase I clinical trial. Another Ebola vaccine, based on an attenuated vesicular stomatitis virus has shown efficacy in postexposure treatment of nonhuman primates to Ebola infection. In this report, we modified the common recombinant adenovirus serotype 5-based Ebola vaccine expressing the wild-type ZEBOV glycoprotein sequence from a CMV promoter (Ad-CMVZGP). The immune response elicited by this improved expression cassette vector (Ad-CAGoptZGP) and its ability to afford protection against lethal ZEBOV challenge in mice was compared to the standard Ad-CMVZGP vector. Methodology/Principal Findings: Ad-CMVZGP was previously shown to protect mice, guinea pigs and nonhuman primates from an otherwise lethal challenge of Zaire ebolavirus. The antigenic expression cassette of this vector was improved through codon optimization, inclusion of a consensus Kozak sequence and reconfiguration of a CAG promoter (Ad- CAGoptZGP). Expression of GP from Ad-CAGoptZGP was substantially higher than from Ad-CMVZGP. Ad-CAGoptZGP significantly improved T and B cell responses at doses 10 to 100-fold lower than that needed with Ad-CMVZGP. Additionally, Ad-CAGoptZGP afforded full protections in mice against lethal challenge at a dose 100 times lower than the dose required for Ad-CMVZGP. Finally, Ad-CAGoptZGP induced full protection to mice when given 30 minutes post-challenge. Conclusions/Significance: We describe an improved adenovirus-based Ebola vaccine capable of affording post-exposure protection against lethal challenge in mice. The molecular modifications of the new improved vaccine also translated in the induction of significantly enhanced immune responses and complete protection at a dose 100 times lower than with the previous generation adenovirus-based Ebola vaccine. Understanding and improving the molecular components of adenovirus-based vaccines can produce potent, optimized product, useful for vaccination and post-exposure therapy. [ABSTRACT FROM AUTHOR]

Wilkie syndrome or superior mesenteric artery syndrome is a rare cause of duodenal obstruction in pediatric and adult age groups. Its manifestations are due to compression of the third portion of the duodenum between the aorta and the superior mesenteric artery. We present one case of a 29-year-old female with a recent history of epigastric pain and severe weight loss due to duodenal obstruction from superior mesenteric syndrome. She was treated conservatively with jejunostomy tube feeding to regain loss of weight. Our case is unique in that the patient has also nutcracker syndrome. [ABSTRACT FROM AUTHOR]

Calorimetry offers a direct measurement of thermodynamic properties of materials, including information on the energetics of phase transitions. Many materials can only be prepared in thin film or small crystal (submilligram) form, negating the use of traditional bulk techniques. The use of micromachined, membrane-based calorimeters for submilligram bulk samples is detailed here. Numerical simulations of the heat flow for this use have been performed. These simulations describe the limits to which this calorimetric technique can be applied to the realm of small crystals (1–1000 μg). Experimental results confirm the feasibility of this application over a temperature range from 2 to 300 K. Limits on sample thermal conductivity as it relates to the application of the lumped and distributed τ2 models are explored. For a typical sample size, the simulations yield 2.5% absolute accuracy for the heat capacity of a sample with thermal conductivity as low as 2×10-5 W/cm K at 20 K, assuming a strong thermal link to the device. Silver paint is used to attach (both thermally and physically) the small samples; its heat capacity and reproducibility are discussed. Measurements taken of a submilligram single crystal of cobalt oxide (CoO) compare favorably to the results of a bulk calorimetric technique on a larger sample. [ABSTRACT FROM AUTHOR]

We calculate the van der Waals energy of a C60 or a C70 fullerene molecule encapsulated in a single-walled carbon nanotube (SWCNT). Orientational degrees of freedom and longitudinal displacements of the molecule are taken into account; calculations are performed for a representative selection of achiral and chiral carbon nanotubes. A simplifying approach, approximating the tube as a continuous cylindrical distribution of carbon atoms, thus focusing on the radius dependence only rather than on the full chirality dependence, is presented. For both fullerene molecules the specific molecular symmetry and the tube symmetry are maximally exploited by using symmetry-adapted rotator functions. For C60, three molecular orientational regimes can be distinguished upon varying the nanotube radius; the smooth-tube approximation is valid for high and intermediate tube radii (&gsim;7 Å) while for low radii (&lsim;7 Å) minor chirality effects come into play. For C70, the continuous-tube approximation works extremely well; we find that for low (&lsim;7 Å) tube radii the “lying” molecular orientation is favorable while for high (&gsim;7.2 Å) radii, the “standing” orientation is recovered—well in agreement with recent X-ray diffraction experiments. The possibility of having transversally displaced molecules is investigated. Chains of C60 and C70 molecules are studied; a one-dimensional liquid description of linear chains of C60 or C70 molecules inside a SWCNT is set up. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 [ABSTRACT FROM AUTHOR]

We calculate the crystal field experienced by a single C 60 molecule encapsulated in a single‐walled carbon nanotube. We take the icosahedral symmetry of the C 60 molecule fully into account by treating it as a cluster of interaction centers. Although we do not distinguish between armchair, zig‐zag and chiral nanotubes since we consider a nanotube as a uniform cylindrical surface density, we can vary the tube radius R T . We observe a flip of the lowest‐energy C 60 molecular orientation when increasing the radius: below R T ≈6.5 Å, the lowest energy occurs when two pentagons are perpendicular to the nanotube's long axis, while for higher values, an orientation with hexagons perpendicular to the tube's long axis is energetically more favorable. Then, we consider a linear chain of C 60 molecules inside a carbon nanotube, all experiencing the crystal field as a confinement potential. We find tube radius‐dependent effects: distinct equilibrium lattice spacings and lattice contractions. We calculate the structure factor and demonstrate the presence of pseudo‐Bragg peaks. Finally, we briefly comment on the calculation of infrared and Raman absorption spectra within the presented framework. [ABSTRACT FROM AUTHOR]

C60 molecules encapsulated in carbon nanotubes interact by van der Waals forces with the tube walls. The nanotube field leads to orientational confinement of the C60 molecules which depends on the nanotube radius. In small tubes with radius RT≤7 Å a fivefold symmetry axis of the molecule coincides with the tube axis, the center of mass of the molecule being located on the tube axis. The interaction between C60 molecules encapsulated in the nanotube is then described by a O2-rotor model on a one-dimensional (1-d) liquid chain with coupling between orientational and displacive degrees of freedom but no long-range order. This coupling leads to a temperature-dependent chain contraction. The structure factor of the 1-d liquid is derived. In tubes with larger radius the molecular centers of mass are displaced off the tube axis. The distinction of two groups of peapods with on- and off-axis molecules suggests an explanation of the apparent splitting of Ag modes of C60 in nanotubes measured by resonant Raman scattering. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the molecular mechanisms of the innate immune responses of Anopheles gambiae against Plasmodium parasites is of great importance for current efforts to develop novel strategies for malaria disease control. The parasite undergoes substantial stage-specific losses during its development in the mosquito, which in some cases lead to complete refractoriness of the mosquito against the parasite. The underlying genetics of refractoriness are complex and multifactorial. Completion of the genome sequence of An. gambiae 2 years ago, together with the development of DNA microarrays in this species and the extension of the RNAi technique to adult mosquitoes, has allowed comparative and functional genomic approaches of the mosquito innate immune system. A variety of factors were shown to negatively affect the development of Plasmodium parasites in the mosquito, in some cases leading to complete transmission blockage. In addition, mosquito factors have been identified that play positive roles and are required for successful transmission of the parasite. These findings indicate a highly complex interplay between parasite and vector. Research is continuing to identify new factors involved in this interaction and to decipher the interplay of these molecules and their regulation. [Copyright &y& Elsevier]

Abstract: Eight limonoids, anthothecanolide (1), 3-O-acetylanthothecanolide (2), 2,3-di-O-acetylanthothecanolide (3), 6R,8α-dihydroxycarapin (4), 3β-acetoxy-3-deoxo-6R-hydroxycarapin (5), methyl angolensate, methyl 6-hydroxyangolensate and khayalactone together with sitosterol glucoside, have been isolated from the extracts of the stem bark of Khaya anthotheca. Compounds 1–4 are described for the first time. Their structures were established by analysis of the high-field NMR and MS data. The structure of compound 4 was confirmed by a single crystal X-ray structure analysis. [Copyright &y& Elsevier]

Neuroimmune interactions are an integral part of gut physiology and involved in the pathogenesis of inflammatory and functional bowel disorders. Mast cells and their mediators are important conveyors in the communication from the innate enteric immune system to the enteric nervous system (ENS). However, it is not known whether a mediator cocktail released from activated human mast cells affects neural activity in the ENS. We used the Multi-Site Optical Recording Technique to image single cell activity in guinea-pig and human ENS after application of a mast cell mediator cocktail (MCMC) that was released from isolated human intestinal mucosa mast cells stimulated by IgE-receptor cross-linking. Local application of MCMC onto individual ganglia evoked an excitatory response consisting of action potential discharge. This excitatory response occurred in 31%, 38% or 11% neurons of guinea-pig submucous plexus, human submucous plexus, or guinea-pig myenteric plexus, respectively. Compound action potentials from nerve fibres or fast excitatory synaptic inputs were not affected by MCMC. This study demonstrates immunoneural signalling in the human gut and revealed for the first time that an MCMC released from stimulated human intestinal mast cells induces excitatory actions in the human and guinea-pig ENS. [ABSTRACT FROM AUTHOR]

The paper presents a discussion between two therapistsone female, the other male, one a clinical psychologist and the other a psychiatrist, one working in an institution and the other in a private practice-each surviving the suicide of a client. It discusses what helped them to continue their psychotherapeutic work following the personal trauma. [ABSTRACT FROM AUTHOR]

Conservation of biodiversity in protected forest areas will be more challenging if local Communities are heavily dependent on then) for energy, nutritional, medicinal and other subsistence needs. This study estimated forest dependency and identified factors influencing dependency for households living around the Nyungwe Forest Reserve (NFR). Rwanda. Data from a household survey conducted in 2001 were analysed using logistic regression analysis. Results suggest that agricultural income. household age and size, and access to towns and outside markets are the key determinants of Forest dependency. Based on these results and discussions with various stakeholders in the study area, it was concluded that protected areas management must be consistent with overall socioeconomic development plans. Towards this end, pine plantations in the NFR butler zone could be replaced with an agroforestry system producing tea, as a potential solution to ensure biodiversity and address subsistence needs of local communities. [ABSTRACT FROM AUTHOR]

Infrared optical fibers based on chalcogenide glass are used as sensor for the determination of volatile organic pollutants in groundwater. The system work following the fiber evanescent wave spectroscopy principle, so-called fiber evanescent wave spectroscopy (FEWS). It was tested in situ, in real time, under real-world conditions. The measurement set-up consisted of a FTIR spectrometer (BRUKER V22), coupled with the fiber (about 2 m), and a cooled mercury–cadmium–telluride detector. A special kit provided by Bruker was connected on the spectrometer to focus the infrared beam from the black body at the entry of the fiber. Some preliminary pilot scale tests, led in an artificial aquifer, show that the fiber permits access to the absorption line positions in a wide range from 4000 to 800 cm-1. Moreover, it is shown that the original design of the fiber enables detection of weak concentrations of pollutants down to 1 ppm of C2Cl4. Then the experiments in “real-world” conditions are carried out after having applied a proper protection on the fibers. A comparison with the chemical analysis data shows that the optical fibers enable to follow the evolution of pollutant rates in water versus time. Finally, this work is promising in view of installing some permanent checking devices into wells to control the rate of pollutants in groundwater of landfill. [Copyright &y& Elsevier]

Transposase activity that mediates the mobility of class II transposable elements, is most commonly initiated by the assembly of higher order synaptic complexes, called transpososomes. The formation of these complexes, that contain the transposable element’s DNA as well as two or more molecules of the transposase, is dependent on interactions between transposase molecules. Using the yeast Two-Hybrid system, we were able to identify three regions mediating multimerization of the Hermes transposase, an element used for germline transformation of insects belonging to the hAT family of transposable elements. One region facilitating protein binding of Hermes transposase molecules was found within the first 252 amino acids of the transposase. The second region was located at the C-terminus of the transposase, and was found to be specific for Hermes transposase multimerization. Amino acids 551–569 were not only required for multimerization but were also necessary for transposition of the element. The third region was located between amino acids 253 and 380 and was found to eliminate the non-specific protein binding ability of the N-terminal protein interaction region but was required for the specific protein binding ability of the C-terminal region of the transposase. Five point mutations affecting the structural integrity of the C-terminal multimerization region abolished or significantly reduced transpositional activity. The same region had been previously identified to mediate dimerization in Activator (Ac), another hAT element, indicating that hAT transposase multimerization is likely to be a prerequisite for mobility of their elements. [Copyright &y& Elsevier]

Infrared optical fibers based on chalcogenides are investigated to optimize their response and they are used for in situ detection of pollutant in groundwater. The pilot scale measurements proved that a Te2As3Se5 (TAS) glass fiber permits access to the absorption line positions of classic pollutants like tetrachloroethylene or dichlorobenzene. Moreover, it has been shown that the original design of the fiber enables detection of weak concentrations of pollutants down to 1 ppm. For experiments in ‘real world’ conditions, optical fibers must be durable under various natural working conditions in ground water. The preliminary mechanical tests demonstrate that efforts have to be done while drawing the fiber to improve their resistance. Nevertheless, at this time, a polymer coated TAS glass fiber is already a useful tool to collect some infrared spectra in landfill. [Copyright &y& Elsevier]

As a consequence of chronically high N depositions in forest ecosystems, the C-to-N ratio of forest floors has narrowed in many forest ecosystems. This might affect the sequestration of soil C and the partitioning of C during decomposition. We investigated samples from Oa layers of 15 different forest floors under Norway spruce (Picea abies Karst. L.) with varying C-to-N ratios in respect to soil respiration, N mineralization and dissolved organic carbon (DOC) release under standardized laboratory conditions. Samples were incubated aerobically at 15 °C and water holding capacity over a period of 10 months. Soil respiration decreased significantly with decreasing C-to-N and increasing N content. The release of DOC increased with increasing C-to-N ratio, while N-mineralization was not affected by C-to-N ratio and N content. Our results support the hypothesis that low C-to-N ratios in later stages of decomposition stabilize soil organic matter and that chronically high N deposition will lead to increased accumulation of C in forest floors. [Copyright &y& Elsevier]

Donor cleavage and strand transfer are two functions performed by transposases during transposition of class II transposable elements. Within transposable elements, the only active center described, to date, facilitating both functions, is the so-called DDE motif. A second motif, R-K-H/K-R-H/W-Y, is found in the site-specific recombinases of the tyrosine recombinase family. While present in many bacterial insertion sequences as well as in the eukaryotic family of mariner/Tc1 elements, the DDE motif was considered absent in other classes of eukaryotic class II elements such as P, and hAT and piggyBac. Based on sequence alignments of a hobo-like element from the nematode Caenorhabditis elegans, to a variety of other hAT transposases and several members of the mariner/Tc1 group, Bigot et al. [Gene 174 (1996) 265] proposed the presence of a DSE motif in hAT transposases. In the present study we tested if each of these three residues is required for transposition of the Hermes element, a member of the hAT family commonly used for insect transformation. While D402N and E572Q mutations lead to knock-out of Hermes function, mutations S535A and S535D did not affect transposition frequency or the choice of integration sites. These data give the first experimental support that D402 and E572 are indeed required for transposition of Hermes. Furthermore, this study indicates that the active center of the Hermes transposase differs from the proposed DSE motif. It remains to be shown if other residues also form the active site of this transposase. [Copyright &y& Elsevier]

AbstractWe report the use of the Hermes transposable element for germ-line transformation of the Mediterranean fruit fly, Ceratitis capitata. Hermes was able to genetically transform this insect at an estimated frequency between 0.6 and 1.1%, which is comparable to the transformation frequencies obtained for this species when using other transposable elements. Hermes integrates into the medfly genome by a cut-and-paste mechanism and the sequences integrated into the genome are delimited by the terminal nucleotides of the Hermes inverted terminal repeats. Integration resulted in the generation of 8 bp target site duplications, the sequences of which conformed to the target site duplications generated by hAT element transposition in insects. The Hermes element is one additional genetic tool that can be deployed in manipulating and characterizing the medfly genome. [ABSTRACT FROM AUTHOR]

Background: National suicide statistics show remarkable differences in the frequencies of various methods used for completed suicide. The WHO/EURO Multicentre Study on Parasuicide makes possible for the first time an international comparison of the frequencies of methods used in attempted suicide, because the data are based on geographical catchment areas of medical institutions.Method: Ongoing standardized monitoring of attempted suicide in all medical institutions serving the catchment areas was performed in 14 centres in 12 European countries. The data analysis is based on 20,649 events involving 15,530 persons, recorded between 1989 and 1993.Results: The comparison of rates per 100,000 shows striking differences between the centres. The highest rates for drug overdoses were found for female attempters in Oxford (347/100,000), Helsinki (238/100,000) and Stockholm (221/100,000). Guipuzcoa had the lowest rates (61/100,000). The differences were most prominent in the age group 15-24, with outstanding rates for women in Oxford (653/100,000), which was mainly due to the frequent use of analgesics. Szeged had outstandingly high rates for pesticides and solvents. In some centres the use of multiple methods was frequent.Conclusions: There is a need, especially for areas with high frequencies for certain methods, to understand the factors involved and to develop new and specific prevention projects and to monitor their effects. The WHO/EURO Multicentre Study on Parasuicide has proved to be a useful and reliable instrument for continuous monitoring of trends in parasuicide. [ABSTRACT FROM AUTHOR]