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Two-dimensional electron gases (2DEGs) are at the base of current nanoelectronics because of their exceptional mobilities. Often the accumulation layer forms at polar interfaces with longitudinal optical (LO) modes. In most cases, the many-body screening of the quasi-2DEGs dramatically reduces the Fröhlich scattering strength. Despite the effectiveness of such a process, it has been recurrently proposed that a remote coupling with LO phonons persists even at high carrier concentration. We address this issue by perturbing electrons in an accumulation layer via an ultrafast laser pulse and monitoring their relaxation via time- and momentum-resolved spectroscopy. The cooling rate of excited carriers is monitored at doping level spanning from the semiconducting to the metallic limit. We observe that screening of LO phonons is not as efficient as it would be in a strictly 2D system. The large discrepancy is due to the remote coupling of confined states with the bulk. Our data indicate that the effect of such a remote coupling can be mimicked by a 3D Fröhlich interaction with Thomas–Fermi screening. These conclusions are very general and should apply to field effect transistors (FET) with high- [Formula: see text] dielectric gates, van der Waals heterostructures, and metallic interfaces between insulating oxides.

International audience; The large tolerance of hybrid perovksites to the trapping of electrons by defects is a key asset in photovoltaic applications. Here, the ionic surface terminations of CH3NH3PbI3 are employed as a testbed to study the effect of electrostatic fields on the dynamics of excited carriers. We characterize the transition across the tetragonal to orthorhombic phase. The observed type II band offset and drift of the excited electrons highlight the important role that organic cations have on the screening of local electrostatic fields. When the orientation of organic cations is frozen in the orthorhombic phase, the positively charged termination induces a massive accumulation of excited electrons at the surface of the sample. Conversely, no electron accumulation is observed in the tetragonal phase. We conclude that the local fields cannot penetrate in the sample when the polarizability of freely moving cations boosts the dielectric constant up to ϵ = 120.

This study is part of the “Milan Cathedral Survey project”. It is a three years long research project with the aim of surveying the entire cathedral in 3D with different techniques (mainly photogrammetry and laser scanning). The goal is to renew the architectonic drawings (sections elevations and plans) to obtain new updated and certificated measurements of the cathedral, as requested by Veneranda Fabbrica del Duomo, and to produce the basis on which to build a future 3D BIM (Building Information Model) system implementation. In this paper, we would like to examine in depth the survey process of the exterior elevations of the cathedral carried out using photogrammetry as the main survey technique for orthophotos production. The case studies here presented have the goal of underlying challenges, discussing decisions and approaches, describing the followed pipeline and of defining a standard method that can be followed to produce gigapixel orthophotos of complex cultural heritages.

Using time-resolved multi-dimensional angle-resolved photoelectron spectroscopy (ARPES) we explore the angular momentum transfer of low energy polarized photons to two prototype topological insulators, Bi 2 Te 2 Se and Bi 2 Se 3 . Our comparative study is based on the analysis of circular dichroism in the photoemission yield of photoexcited Dirac states, and reveals that the spin vector of in-gap Dirac electrons in Bi 2 Te 2 Se presents a more pronounced out-of-plane component compared to that of Bi 2 Se 3 . We show that the multi-dimensional ARPES approach can be effectively used to observe the spin texture of photoexcited topological insulators, and to unambiguously disentangle experimental geometry and matrix element effects.

Modern technology offers elaborated and efficient instruments capable of performing extremely accurate surveys of architectural and archaeological remains. However, not all of them can be used everywhere: archaeological missions might be constrained by logistics, environmental and, especially, financial restrictions. This issue is especially felt by archaeological missions currently operating in the Middle East and Africa. The research team of the ERC project LIFE (CoGrant 681673) has been successfully experimenting with the use of low-cost instruments to achieve equally accurate results.

Since 2008, an intense survey has been underway in the Milan Cathedral. The operations, over the years, have been conducted with laser scanner and photogrammetry choosing or integrating the different methodologies according to the environment, the necessary “drawing” to support the different sites’ maintenance operation but always concurrently with the evolution of the method and the software. The “principal actor” of conservation activities is the “marble block.” The Veneranda Fabbrica organizes the activities identifying the areas that are in need of intervention and identifying which blocks will be affected by replacement operations, tessellation, or consolidation. Thus, the objective of the survey activities and the subsequent modeling phase was to build a detailed 3D model in which the marble blocks are easily recognizable in terms of their shape, size, position, and texture (only for the outer part). All the elaborations produced, the 3D models, the two-dimensional representations, and the orthophotos, allow for the identification of the blocks, as to provide proper technical support for site operations. In parallel with the survey and modeling activities, an ad hoc online information system was created to support the construction site activities in a smart manner. The system allows for the consultation and the sharing of the 3D models and all the data necessary for maintenance operations of the entire Cathedral.

Summary Background Whether blood eosinophil counts and exhaled nitric oxide (FeNO) are associated with important outcomes in mild asthma is unclear. In this prespecified subgroup analysis of a previously published open-label clinical trial, we aimed to assess associations between blood eosinophil counts and FeNO with outcomes and response to asthma treatment. Methods In the previously reported 52-week, open-label, randomised controlled trial, people with mild asthma receiving only β agonist reliever inhalers were enrolled at one of 16 clinical trials units in New Zealand, the UK, Italy, or Australia. Eligible participants were randomly assigned (1:1:1, stratified by country), to receive inhalers to take as-needed salbutamol (two inhalations of 100 μg in a pressurised metered dose inhaler), maintenance budesonide (200 μg twice per day by inhaler) plus as-needed salbutamol (two inhalations of 100 μg), or as-needed budesonide–formoterol (one inhalation of 200 μg budesonide and 6μg formoterol by inhaler). The primary outcome was the annual rates of asthma exacerbations per patient, and in this prespecified subgroup analysis, we assessed whether annual exacerbation rates in each treatment group were significantly different depending on levels of blood eosinophil count, FeNO, or a composite score of both. Analyses were done for patients with available biomarker measurements The study was registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12615000999538. Findings 675 participants were enrolled between March 17, 2016, and Aug 29, 2017, of whom 656 had results for blood eosinophil analysis and 668 had results for FeNO. Of the patients who received as-needed salbutamol, the proportion of patients having a severe exacerbation increased progressively with increasing blood eosinophil count (two [4%] of 49 participants with Interpretation In patients with mild asthma, the effects of as-needed budesonide–formoterol on exacerbations are independent of biomarker profile, whereas the benefits of maintenance inhaled budesonide are greater in patients with high blood eosinophil counts than in patients with low counts. Funding AstraZeneca, Health Research Council of New Zealand.

International audience; Hybrid heterostructures, made of organic molecules adsorbed on two-dimensional metal monochalcogenide, generally unveil interfacial effects that improve the electronic properties of the single constitutive layers. Here, we investigate the interfacial electronic characteristics of the F4-TCNQ/single-layer GaSe heterostructure. A sharp F4-TCNQ/GaSe interface has been obtained and characterized by x-ray photoemission spectroscopy. We demonstrate that a high electron transfer from 1TL GaSe into the adsorbed F4-TCNQ molecules takes place, thereby yielding a reduction in the excess negative charge density of GaSe. Additionally, the direct band-structure determination of the heterostructure has been carried out using angle-resolved photoemission spectroscopy, shedding light on essential features such as doping and band offset at the interface. Our results indicate that the buried 1TL GaSe below the F4-TCNQ layer exhibits a robust inversion of the valence dispersion at the Γ point, forming a Mexican-hat-shaped dispersion with 120 ± 10 meV of depth. Our experiments also reveal that F4-TCNQ can significantly tune the electronic properties of 1TL GaSe by shifting the band offset of about 0.16 eV toward lower binding energies with respect to the Fermi level, which is a key feature for envisioning its applications in nanoelectronics.

Using femtosecond time- and angle-resolved photoemission spectroscopy, we explore the out-of-equilibrium dynamics of surface fermions in the topological system ${\mathrm{Bi}}_{2}{\mathrm{Te}}_{2}\mathrm{Se}$. We show that the presence of localized states from defects at the surface is one of the key material parameters undergirding the long relaxation time of photoexcited Dirac electrons lying in the projected band gap of the bulk-insulating pristine compound. Doping this ternary compound with Sn substituting on Bi sites, while desirably increasing the resistivity at low temperatures decreases decay times of the excited homologous Dirac electrons. On the basis of these observations, we argue that long relaxation times can be ultimately controlled by a charge transfer to the surface.

International audience; The rapid development of the computational methods based on density functional theory, on the one hand, and of time-, energy-, and momentum-resolved spectroscopy, on the other hand, allows today an unprecedently detailed insight into the processes governing hot-electron relaxation dynamics, and, in particular, into the role of the electron–phonon coupling. Instead of focusing on the development of a particular method, theoretical or experimental, this review aims to treat the progress in the understanding of the electron–phonon coupling which can be gained from both, on the basis of recently obtained results.We start by defining several regimes of hot electron relaxation via electron–phonon coupling, with respect to the electron excitation energy. We distinguish between energy and momentum relaxation of hot electrons, and summarize, for several semiconductors of the IV and III–V groups, the orders of magnitude of different relaxation times in different regimes, on the basis of known experimental and numerical data. Momentum relaxation times of hot electrons become very short around 1 eV above the bottom of the conduction band, and such ultrafast relaxation mechanisms are measurable only in the most recent pump-probe experiments.Then, we give an overview of the recent progress in the experimental techniques allowing to obtain detailed information on the hot-electron relaxation dynamics, with the main focus on time-, energy-, and momentum-resolved photoemission experiments. The particularities of the experimental approach developed by one of us, which allows to capture time-, energy-, and momentum-resolved hot-electron distributions, as well as to measure momentum relaxation times of the order of 10 fs, are discussed.We further discuss the main advances in the calculation of the electron–phonon scattering times from first principles over the past ten years, in semiconducting materials. Ab initio techniques and efficient interpolation methods provide the possibility to calculate electron–phonon scattering times with high precision at reasonable numerical cost. We highlight the methods of analysis of the obtained numerical results, which allow to give insight into the details of the electron–phonon scattering mechanisms.Finally, we discuss the concept of hot electron ensemble which has been proposed recently to describe the hot-electron relaxation dynamics in GaAs, the applicability of this concept to other materials, and its limitations. We also mention some open problems.

We monitor the dynamics of hot carriers in InSe by means of two-photon photoelectron spectroscopy (2PPE). The electrons excited by photons of 3.12 eV experience a manifold relaxation. First, they thermalize to electronic states degenerate with the $\overline{M}$ valley. Subsequently, the electronic cooling is dictated by Fr\"ohlich coupling with phonons of small momentum transfer. Ab initio calculations predict cooling rates that are in good agreement with the observed dynamics. We argue that electrons accumulating in states degenerate with the $\overline{M}$ valley could travel through a multilayer flake of InSe with a lateral size of 1 $\ensuremath{\mu}\mathrm{m}$. The hot carriers pave a viable route to the realization of below-band-gap photodiodes and Gunn oscillators. Our results indicate that these technologies may find a natural implementation in future devices based on layered chalcogenides.

We address the role of nonlocal Coulomb correlations and short-range magnetic fluctuations in the high-temperature phase of ${\mathrm{Sr}}_{2}{\mathrm{IrO}}_{4}$ within state-of-the-art spectroscopic and first-principles theoretical methods. Introducing an ``oriented-cluster dynamical mean-field scheme'', we compute momentum-resolved spectral functions, which we find to be in excellent agreement with angle-resolved photoemission spectra. We show that while short-range antiferromagnetic fluctuations are crucial to accounting for the electronic properties of ${\mathrm{Sr}}_{2}{\mathrm{IrO}}_{4}$ even in the high-temperature paramagnetic phase, long-range magnetic order is not a necessary ingredient of the insulating state. Upon doping, an exotic metallic state is generated, exhibiting cuprate-like pseudo-gap spectral properties, for which we propose a surprisingly simple theoretical mechanism.

We present a time- and angle-resolved photoemission study of the transition-metal dichalcogenide ${\mathrm{WTe}}_{2}$, a candidate type-II Weyl semimetal exhibiting extremely large magnetoresistence. Using femtosecond light pulses, we characterize the unoccupied states of the electron pockets above the Fermi level. Following the ultrafast carrier relaxation in distinct parts of the Brillouin zone, we report remarkably similar decay dynamics for electrons and holes. Our results confirm that charge compensation between electron and hole pockets---a key effect to explain the nonsaturating magnetoresistance of this material---is a distinctive feature of ${\mathrm{WTe}}_{2}$ even in an out-of-equilibrium regime.

International audience; We review measurements of angle and time resolved photoelectron spectroscopy on the surface states of the Bi(1 1 1) surface. The work covers several aspects of these surface states, discussing the topological properties, the strong anisotropy of the spin–orbit splitting and the dynamical relaxation of photoexcited electrons. Since time resolved experiments disentagle interaction processes in real time, the reported data offer a novel perspective on the motion of charge carriers in surface states and will serve as an unuseful reference for other systems with strong spin–orbit coupling.

We report time- and angle-resolved spectroscopic measurements in optimally doped ${\mathrm{Bi}}_{2}{\mathrm{Sr}}_{2}{\mathrm{CaCu}}_{2}{\mathrm{O}}_{8+\ensuremath{\delta}}$. The photoelectron intensity maps are monitored as a function of temperature, photoexcitation density, and delay time from the pump pulse. We evince that thermal fluctuations are effective only for temperatures near the critical value whereas photoinduced fluctuations scale linearly at low pumping fluence. The minimal energy to fully disrupt the superconducting gap slightly increases when moving off the nodal direction. No evidence of a pseudogap arising from other phenomena than pairing has been detected in the explored region of reciprocal space. On the other hand, a model accounting for the finite pair breaking explains the gap filling both in the near-nodal as well as in the off-nodal direction. Finally, we observed that nodal quasiparticles develop a faster dynamics when pumping the superconductor with fluence large enough to induce the total collapse of the gap.

We discuss the application of time-resolved ultrafast angle resolved photoelectron spectroscopy to the study of photoexcited topological insulators. Measurements performed on the prototype material Bi2Te3 clearly show that all the main processes involved in the ultrafast surface carrier dynamics of topological insulators can be clearly observed and quantitatively analyzed. The comparison with other experimental results shows that the relative position of surface and bulk conduction bands with respect to the system Fermi level play an essential role in the recombination processes following ultrafast optical excitation.

New data on Bi 2 Sr 2 CaCu 2 O 8+δ (Bi2212) reveal interesting aspects of photoexcited superconductors. The electrons dynamics show that inelastic scattering by nodal quasiparticles decreases when the temperature is lowered below the critical value of the superconducting phase transition. This drop of electronic dissipation is astonishingly robust and survives to photoexcitation densities much larger than the value sustained by long-range superconductivity. The unconventional behavior of quasiparticle scattering is ascribed to superconducting correlations extending on a length scale comparable to the inelastic mean-free path. Our measurements indicate that strongly driven superconductors enter in a regime without phase coherence but finite pairing amplitude.

Topological insulators are transformative quantum solids with immune-to-disorder metallic surface states having Dirac band structure. Ubiquitous charged bulk defects, however, pull the Fermi energy into the bulk bands, denying access to surface charge transport. Here we demonstrate that irradiation with swift ($\sim 2.5$ MeV energy) electron beams allows to compensate these defects, bring the Fermi level back into the bulk gap, and reach the charge neutrality point (CNP). Controlling the beam fluence we tune bulk conductivity from \textit{p}- (hole-like) to \textit{n}-type (electron-like), crossing the Dirac point and back, while preserving the Dirac energy dispersion. The CNP conductance has a two-dimensional (2D) character on the order of ten conductance quanta $G_0 =e^2/h$, and reveals, both in Bi$_2$Te$_3$ and Bi$_2$Se$_3$, the presence of only two quantum channels corresponding to two topological surfaces. The intrinsic quantum transport of the topological states is accessible disregarding the bulk size., Comment: Main manuscript - 12 pages, 4 figures; Supplementary file - 15 pages, 11 figures, 1 Table, 4 Notes

Apprenticeship is a period of increased risk of developing work-related respiratory allergic diseases. There is a need for documents to provide appropriate professional advice to young adults aiming to reduce unsuitable job choices and prevent impairment from their careers. The present document is the result of a consensus reached by a panel of experts from European and non-European countries addressed to allergologists, pneumologists, occupational physicians, primary care physicians, and other specialists interested in this field, which aims to reduce work-related respiratory allergies (rhinoconjunctivitis and asthma) among allergic or nonallergic apprentices and other young adults entering the workforce. The main objective of the document is to issue consensus suggestions for good clinical practice based on existing scientific evidence and the expertise of a panel of physicians.

To cite this article: Moscato G, Pala G, Perfetti L, Frascaroli M, Pignatti P. Clinical and inflammatory features of occupational asthma caused by persulphate salts in comparison with asthma associated with occupational rhinitis. Allergy 2010; 65: 784–790. Abstract Background: The relationships between asthma and rhinitis are still a crucial point in respiratory allergy and have scarcely been analysed in occupational setting. We aimed to compare the clinical and inflammatory features of subjects with occupational asthma only (OA) to subjects with OA associated to occupational rhinitis (OAR) caused by persulphate salts. Methods: The clinical charts of 26 subjects diagnosed in our Unit as respiratory allergy caused by ammonium persulphate (AP), confirmed by specific inhalation challenge (SIC), were reviewed. Twenty-two out of twenty-six patients underwent pre-SIC-induced sputum challenge test (IS) and 24/26 underwent nasal secretion collection and processing. Results: Twelve out of twenty-six patients received a diagnosis of OA-only and 14/26 of OAR. Duration of exposure before diagnosis, latency period between the beginning of exposure and asthma symptom onset, basal FEV1, airway reactivity to methacholine and asthma severity did not differ in the two groups. Eosinophilic inflammation of upper and lower airways characterized both groups. Eosinophil percentage in IS tended to be higher in OAR [11.9 (5.575–13.925)%] than in OA-only [2.95 (0.225–12.5)%] (P = 0.31). Eosinophilia in nasal secretions was present both in subjects with OAR [55 (46–71)%] and in subjects with OA-only [38 (15–73.5)%], without any significant difference. Discussion: Our results indicate that OA because of ammonium persulphate coexists with occupational rhinitis in half of the patients. Unexpectedly, rhinitis did not seem to have an impact on the natural history of asthma. The finding of nasal inflammation in subjects with OA-only without clinical manifestations of rhinitis supports the united airway disease concept in occupational respiratory allergy as a result of persulphates.

Obtaining insight into microscopic cooperative effects is a fascinating topic in condensed matter research because, through self-coordination and collectivity, they can lead to instabilities with macroscopic impacts like phase transitions. We used femtosecond time- and angle-resolved photoelectron spectroscopy (trARPES) to optically pump and probe TbTe 3 , an excellent model system with which to study these effects. We drove a transient charge density wave melting, excited collective vibrations in TbTe 3 , and observed them through their time-, frequency-, and momentum-dependent influence on the electronic structure. We were able to identify the role of the observed collective vibration in the transition and to document the transition in real time. The information that we demonstrate as being accessible with trARPES will greatly enhance the understanding of all materials exhibiting collective phenomena.

The present document is the result of a consensus reached by a panel of experts from European and nonEuropean countries on Occupational Rhinitis (OR), a disease of emerging relevance, which has received little attention in comparison to occupational asthma. The document covers the main items of OR including epidemiology, diagnosis, management, socio-economic impact, preventive strategies and medicolegal issues. An operational definition and classification of OR tailored to that of occupational asthma, as well as a diagnostic algorithm based on steps allowing different levels of diagnostic evidence, are proposed. The needs for future research are pointed out. Key messages are issued for each item.

The optical properties of single-wall carbon nanotube sheets in the far-infrared have been investigated with THz time-domain spectroscopy. Over a wide frequency range from 1 THz to 40 THz, the complex dielectric function of the nanotube sample has been derived. Our data can be excellently reproduced by a Drude-Lorentz model function. The extracted fit parameters such as Lorentz resonance frequency and plasma frequency are consistent with values obtained by scanning tunneling techniques. We discuss the origin of both the Lorentz and Drude contribution in terms of direct and indirect optical transitions.

We study with Angle Resolved PhotoElectron Spectroscopy (ARPES) the evolution of the electronic structure of Sr2IrO4, when holes or electrons are introduced, through Rh or La substitutions. At low dopings, the added carriers occupy the first available states, at bottom or top of the gap, revealing an anisotropic gap of 0.7eV in good agreement with STM measurements. At further doping, we observe a reduction of the gap and a transfer of spectral weight across the gap, although the quasiparticle weight remains very small. We discuss the origin of the in-gap spectral weight as a local distribution of gap values.

We perform time resolved photoelectron spectroscopy measurements of optimally doped $\tn{Bi}_2\tn{Sr}_2\tn{CaCu}_2\tn{O}_{8+\delta}$ (Bi-2212) and $\tn{Bi}_2\tn{Sr}_{2-x}\tn{La}_{x}\tn{Cu}\tn{O}_{6+\delta}$ (Bi-2201). The electrons dynamics show that inelastic scattering by nodal quasiparticles decreases when the temperature is lowered below the critical value of the superconducting phase transition. This drop of electronic dissipation is astonishingly robust and survives to photoexcitation densities much larger than the value sustained by long-range superconductivity. The unconventional behaviour of quasiparticle scattering is ascribed to superconducting correlations extending on a length scale comparable to the inelastic path. Our measurements indicate that strongly driven superconductors enter in a regime without phase coherence but finite pairing amplitude. The latter vanishes near to the critical temperature and has no evident link with the pseudogap observed by Angle Resolved Photoelectron Spectroscopy (ARPES)., Comment: 7 pages, 5 Figures

Time-resolved THz spectroscopy is employed to investigate the ultrafast electron dynamics in gaseous Ar, SF 6 , and an Ar–SF 6 mixture following ionization by an intense femtosecond laser pulse. The THz response of the free electrons can be described by the Drude model and yields the temporal evolution of the electron density and collision rate. The free-electron decay in the Ar plasma is accelerated enormously by adding small amounts of the electron scavenger SF 6 . This observation is assigned to electron attachment to SF 6 and allows us to infer an electronic temperature of about 20 000 K. The electron collision rate reflects the dynamics of the ion density showing that anions and cations neutralize on a 10-ps time scale.

Background: Several studies have provided evidence of a strong association between asthma and allergic or nonallergic rhinitis, leading to the hypothesis that allergic rhinitis (AR) and asthma represent a continuum of the same disease. Aim: The aims of our study were: (i) to measure the comorbidity of AR and asthma and asthma-like symptoms and (ii) to assess whether asthma, AR, and their coexistence share a common pattern of individual risk factors. Methods: The subjects are participants from the Italian multicentre, cross-sectional survey on respiratory symptoms in the young adult general population (Italian Study of Asthma in Young Adults, ISAYA). The relationship between individual risk factors and asthma, AR and their coexistence, was studied by means of a multinomial logistic regression. Results: About 60% of asthmatics reported AR. On the other hand, subjects with AR presented an eightfold risk of having asthma compared to subjects without AR. Age was negatively associated with asthma [OR = 0.89, 95% confidence interval (CI): 0.82–0.96], AR (OR = 0.92, 95% CI: 0.86–0.98), and asthma associated with AR (OR = 0.83, 95% CI: 0.79–0.88). The risk of AR without asthma was significantly higher in the upper social classes (OR = 1.23, 95% CI: 1.08–1.39). Active current smoking exposure was positively associated with asthma alone (OR = 1.24, 95% CI: 1.09–1.41) and negatively associated with AR with (OR = 0.69, 95% CI: 0.54–0.88) or without (OR = 0.76, 95% CI: 0.69–0.84) asthma. Conclusions: Asthma and AR coexist in a substantial percentage of patients; bronchial asthma and AR, when associated, seem to share the same risk factors as AR alone while asthma without AR seems to be a different condition, at least with respect to some relevant risk factors.

We discuss the spectral signatures of strong electronic correlations and electron-phonon interactions in two representative low-dimensional systems. In the 2D compound 1T-TaSe2 a charge-density-wave (CDW) induces a narrowing of the conduction band, which triggers a surface metal-insulator (M-I) transition and the disappearance of the quasiparticle (QP) features. In the 1D blue bronze K0.3MoO3 strong interaction with the lattice lead to pseudogapped polaronic lineshapes, and the large mass renormalization masks the signatures of electronic correlations. (C) 2004 Elsevier B.V All rights reserved.

Background Two types of OA are distinguished: immunological (OA with sensitization) and non-immunological, i.e., irritant induced asthma or reactive airways dysfunction syndrome (RADS). Methods We describe the case of a worker who developed respiratory symptoms after a spill of diphenylmethane diisocyanate (MDI) at the workplace. RADS was initially diagnosed and the worker resumed working. The progressive worsening of symptoms and the appearance of symptoms–work relationship one year later, when concentrations of isocyanates were no longer “irritant,” suggested immunological OA. Results The diagnosis was confirmed by specific inhalation challenge test, followed by removal from exposure and complete recovery. Conclusions In the case of RADS due to an agent with both irritant and sensitizing properties, history should be repeatedly assessed for a possible symptom–work relationship. If this is found, further investigations should be carried out, including specific inhalation challenges, to confirm the possibility of immunological OA. Am. J. Ind. Med. 44:325–328, 2003. © 2003 Wiley-Liss, Inc.

We exploited angle-resolved photoemission (ARPES) to investigate the nature of the elementary quasiparticle (QP) excitations in selected low-dimensional compounds. In the model quasi two-dimensional conductor TiTe2, we observe spectral lineshapes which are consistent with a Fermi liquid (FL) scenario, and the usual QP scattering mechanisms. In contrast, in typical quasi one-dimensional Peierls systems like TTF-TCNQ, (TaSe4)(2)I and K0.3MoO3 we find clear non-FL lineshapes. We briefly discuss the possible origins of these unusual properties. (C) 2002 Elsevier Science B.V. All rights reserved.

Background: CD69 is a molecule expressed on human eosinophils after cytokine-activation. Different studies have described the eosinophil activation, evaluated by CD69 expression, at the site of an allergic inflammation. In this study we evaluated the expression of CD69 on peripheral blood eosinophils after a specific inhalation challenge (SIC), in order to better define the state of activation of peripheral blood eosinophils after exposure to sensitizers. Methods: CD69 expression was evaluated by flow cytometry in nine asthmatic patients before and after a positive SIC with high or low molecular weight agents (pollens, house dust mites, Penicillia, isocyanates) and in 11 asthmatic patients who underwent an inhalation challenge with placebo. CD69 expression was evaluated at baseline, 120 min, and 240 min after the SIC or the placebo. Results: Baseline (before challenge) CD69 expression was comparable between the group of SIC positive patients and the placebo group. CD69 expression on peripheral eosinophils significantly increased 240 min after the challenge in positive SIC patients compared to placebo. In patients with a positive SIC the percentage of peripheral blood eosinophils significantly decreased at 120 and 240 min after the inhalation challenge with respect to the baseline. Conclusion: CD69 expression on peripheral blood eosinophils is significantly increased in asthmatic patients after exposure to the sensitizing agent. These data show that the effects of a bronchial stimulation are also detectable on peripheral blood eosinophils.

Time-resolved experiments visualize the motion of electrons in bilayer graphene, confirming the material behaves as a semiconductor that has potential for electronics applications.

Exposure to cat allergen at school might exacerbate symptoms in asthmatic children with cat allergy. To study this, we identified 410 children, 6-12 yr of age, who were being treated for asthma (inhaled steroids and beta-agonists), were allergic to cats, and had no cat at home. Peak expiratory flow (PEF), asthma symptoms, medication, fever and/or sore throat, and contact with furred pets were recorded twice daily during the last week of summer holidays and the second and third weeks of school. The number of cat owners in each class was recorded. Ninety-two children with asthma reported no contact with furred pets. Among these, children who attended classes with18% (median value) cat owners reported significantly decreased PEF, more days with asthma symptoms, and increased use of medication after school started. Those in classes withor = 18% cat owners reported no change. Children in classes with many cat owners ran a 9-fold increased risk of exacerbated asthma after school start compared with children in classes with few cat owners, after adjusting for age, sex, and fever and/or sore throat. Thus, asthma symptoms, PEF, and the use of asthma medication in children with cat allergy may be affected by indirect cat exposure at school.

Background: HDM distribution varies between geographic areas and may be affected by housing characteristics. We quantified Der p 1 and Der f 1 and assessed the relationships between their levels and housing characteristics in homes of nonallergic subjects. Methods: Der f 1 and Der p 1 were measured by ELISA in dust samples from living-room floors and mattresses of 44 homes of nonallergic subjects in Pavia. Information about household characteristics was obtained by questionnaire. Results: Der p 1 and Der f 1 concentrations (μg/g dust, median) were 0.34 and 7.8 on mattresses, and 0.15 and 0.83 on living-room floors. Higher Der f 1 levels on mattresses were associated with synthetic pillows (P

Boron neutron capture therapy (BNCT) is an experimental, binary treatment for brain cancer which requires as the first step that tumor tissue is targeted with a boron-10 containing compound. Subsequent exposure to a thermal neutron flux results in destructive, short range nuclear reaction within 10 microm of the boron compound. The success of the therapy requires than the BNCT agents be well localized in tumor, rather than healthy tissue. The MEPHISTO spectromicroscope, which performs microchemical analysis by x-ray absorption near edge structure (XANES) spectroscopy from microscopic areas, has been used to study the distribution of trace quantities of boron in human brain cancer tissues surgically removed from patients first administered with the compound Na2B12H11SH (BSH). The interpretation of XANES spectra is complicated by interference from physiologically present sulfur and phosphorus, which contribute structure in the same energy range as boron. We addressed this problem with the present extensive set of spectra from S, B, and P in relevant compounds. We demonstrate that a linear combination of sulfate, phosphate and BSH XANES can be used to reproduce the spectra acquired on boron-treated human brain tumor tissues. We analyzed human glioblastoma tissue from two patients administered and one not administered with BSH. As well as weak signals attributed to BSH, x-ray absorption spectra acquired from tissue samples detected boron in a reduced chemical state with respect to boron in BSH. This chemical state was characterized by a sharp absorption peak at 188.3 eV. Complementary studies on BSH reference samples were not able to reproduce this chemical state of boron, indicating that it is not an artifact produced during sample preparation or x-ray exposure. These data demonstrate that the chemical state of BSH may be altered by in vivo metabolism.

Note: Ecole Polytech Fed Lausanne, CH-1015 Lausanne, Switzerland. Zwick, F, Ecole Polytech Fed Lausanne, CH-1015 Lausanne, Switzerland.ISI Document Delivery No.: 278YTTimes Cited: 0Cited Reference Count: 0 Reference LSE-ARTICLE-1999-033View record in Web of Science Record created on 2006-10-03, modified on 2017-05-12

BACKGROUND Serum eosinophil cationic protein (sECP) has been proposed as a marker of disease activity in bronchial asthma. The study aimed to evaluate the role of sECP in screening asthmatics in a group of subjects with asthma and rhinitis symptoms, and the relationship between sECP and clinical and functional parameters of asthma. METHODS A total of 185 subjects with asthma symptoms, 149 of them with rhinitis as well, underwent skin tests, spirometry, methacholine (MCH) test, blood sampling for eosinophil percentage (bEOS%) and sECP determination, and nasal secretions smear for eosinophil percentage (nEOS%) determination; PEF values, symptoms, and medication over a period of 4 weeks after sampling for sECP quantitation were recorded on a diary. RESULTS A total of 99 (53%) subjects received a diagnosis of asthma (asthmatics), and 86 did not (nonasthmatics). In asthmatics, neither sECP nor bEOS% was significantly different from nonasthmatics. In asthmatics, sECP was higher in subjects with increased than in those with normal daily PEF variability (16.4, 6.8-24.4 vs 5.3, 3.9-8.4 microg/l; P

Aim To evaluate the clinical outcome and socioeconomic consequences of occupational asthma (OA). Subjects and methods Twenty-five patients with OA both to high- and low-molecular-weight agents (3 and 22, respectively) confirmed by specific inhalation challenge were followed up for 12 months after the diagnosis. Upon diagnosis, each patient received a diary on which to report peak expiratory flow rate (PEFR), symptoms, drug consumption, expenses directly or indirectly related to the disease, as well as information regarding personal socioeconomic status. At each follow-up visit (1, 3, 6, and 12 months), the patients underwent clinical examination, spirometry, methacholine (Mch) challenge, and assessment of diary-derived parameters and socioeconomic status. Asthma severity (AS) was classified into four levels, based on symptoms, drug consumption, and PEFR variability. Results At 12 months, 13 patients (group A) had ceased exposure; the remaining 12 patients (group B) continued to be exposed. At diagnosis, FEV1 percent and provocative dose causing a 20% fall in FEV1 (PD20) of Mch were lower in group A than in group B; patients of group A were also characterized by significantly higher basal AS levels. At 12 months, no significant variation in FEV1 percent or PD20 was found for either group, while AS levels improved in both groups, the change being more marked for group A than group B. Pharmaceutical expense at 12 months significantly (p Conclusions In OA, cessation of exposure to the offending agent results in a decrease in asthma severity and in pharmaceutical expenses, but it is associated with a deterioration of the individual's socioeconomic status (professional downgrading and loss of work-derived income). There appears to be a great need for legislation that facilitates the relocation of these patients.

Peak expiratory flow (PEF) monitoring is often used to establish the relationship between occupational exposure and asthma. FEV1 has been found to be a better physiologic index than PEF in the measurement of airflow obstruction. The aim of this study was to compare the accuracy of serial monitoring of PEF and FEV1 in the diagnosis of occupational asthma. Twenty consecutive subjects referred for possible occupational asthma were asked to perform serial monitoring of PEF and FEV1 using a portable ventilometer. Two sets of graphs were plotted for both PEF and FEV1: graphs with the best of all values and graphs with the best of two reproducible values. Three observers interpreted both PEF and FEV1 recordings by the visual method in a blind, randomized manner as either compatible with occupational asthma or not. Eleven of the subjects had a positive inhalation challenge test (high-molecular-weight agents, n = 6; low-molecular-weight agents, n = 5). In the case of analysis of the graphs plotted with the best of all values, the sensitivity of the PEF recording interpreted by the three observers was 82, 73, and 73%, and of the FEV1 recording as 55, 55, and 45%; specificity of PEF recording was 89, 100, and 100%, and of FEV1 was 56, 89, and 100%. When an agreement between two of the three readers was required to define occupational asthma, sensitivity and specificity were 73 and 100% for PEF and 55 and 89% for FEV1. Lower sensitivities were found when the same analyses were performed with the graphs plotted with the best of two reproducible values. It was concluded that unsupervised FEV1 is not more accurate than unsupervised PEF monitoring in the diagnosis of occupational asthma. Plotting graphs using the best value gives better diagnostic accuracy than plotting them with the best of two reproducible values.