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The mitigation of seismic risk for historic buildings faces the critical problem of needing interventions that sometimes can be extremely invasive, thus not respectful of the overall integrity of the valuable structure to protect. Because of this, interventions in the subsoil, possibly without even touching the structure, are appealing, making Geotechnical Seismic Isolation (GSI) of extreme interest for the preservation of the built heritage. The paper shows the results of a centrifuge test carried out to check the simplest possible GSI solution: The lateral disconnection of a shallow foundation, obtained by removing the soil on the sides of the foundation. In this way, the foundation-soil contact will be through the lower base only. The results obtained on two identical structures, one with and one without disconnection, demonstrates that the latter has the beneficial effect of elongating the fundamental period of the soil-structure system in such a way to reduce significantly structural demand. In order to extract additional results, a numerical back analysis of the centrifuge test was also carried out. Since the lateral disconnection does not touch the structure, the integrity of the building to be protected is fully preserved.

The FAMU experiment aims to accurately measure the hyperfine splitting of the ground state of the muonic hydrogen atom. A measurement of the transfer rate of muons from hydrogen to heavier gases is necessary for this purpose. In June 2014, within a preliminary experiment, a pressurized gas-target was exposed to the pulsed low-energy muon beam at the RIKEN RAL muon facility (Rutherford Appleton Laboratory, U.K.). The main goal of the test was the characterization of both the noise induced by the pulsed beam and the X-ray detectors. The apparatus, to some extent rudimental, has served admirably to this task. Technical results have been published that prove the validity of the choices made and pave the way for the next steps. This paper presents the results of physical relevance of measurements of the muon transfer rate to carbon dioxide, oxygen, and argon from non-thermalized excited μp atoms. The analysis methodology and the approach to the systematics errors are useful for the subsequent study of the transfer rate as function of the kinetic energy of the μp currently under way. © 2018 The Author(s).

Background Biobadasar is a registry that monitors adverse events in patients who use biological treatments in rheumatologic diseases conducted by the Argentine Society of Rheumatology. As in others international registries the community acquired pneumonia (CAP) has been detected as one of the most frequent infectological adverse events. Although all immunosuppressed patients should be vaccinated against streptococcus pneumoniae, there is a proportion of patients who are not. Objectives Evaluate the prevalence of pneumococcal vaccination in patients with CAP within the Biobadasar database. Assess factors associated with Severe CAP in these patients. Methods A cross-sectional, multicentric study was made in BIOBADASAR database from 2010 to2016. In patients who reported CAP data of demographics, comorbidities and state of pneumococcal immunization was collected. Microbiological data, treatment and outcome of the event were considered. The severity of CAP was assessed according to the opinion of the attending physician, hospitalization, risk of life and/or death. Values are expressed as mean ± standard deviation, median (ranges) and frequencies (percentages), as appropriate. We performed bivariate and multivariate logistic regression analysis to identify variables associated with the event. Results Of the 4029 patients enrolled in the registry, the cumulative incidence of CAP was 4.2% (n 170), 72.4% (n 123) were women. The mean age was 57 (SD +/- 14.5). Biological treatment was found in 81.8% (n 139). Patient s that have received the pneumococcal vaccine were 40.6% (n=69). Severe CAP was detected in 7.1%. Streptococco Pneumoniae was the main pathogen isolated in 13% of the cases. Overall mortality was 4.1%. In the univariate analysis for severe CAP we found statistical significance for Smoking OR 3.88, CI95 1.063–14.22, p= 0.029 and chronic kidney disease (CKD) OR 31, CI95 2.6–376, p= 0.007. When performing a multiple logistic regression model, only renal failure OR 7.39 CI95 0.003–0.38 p= 0.007 was a predictor of severe CAP. Not significative association with immunosuppressive treatment (p: 0.09), age (p: 0.464), or vaccination (p: 0.937) Conclusions The annual incidence of CAP in Argentina varies between 0.5 -1.1% while in our cohort it was four times higher. The prevalence of pneumococcal vaccination was less than 50%, showing that, although the literature and guidelines establish the need for vaccination, this is not so in the real world. In the multivariate analysis, only CKD was related to severe CAP. Although in the univariate analysis the CKD and the smoking habit represented factors associated with severity. We must emphasize the medical education in following the international vaccination guidelines. Disclosure of Interest None declared

This paper examines the reactivity of catalysts based on niobium oxide dispersed in silica, for the oxidation of 2-methyl-1-naphthol to 2-methyl-1,4-naphthoquinone (menadione) with aqueous hydrogen peroxide. The catalytic performance is affected by the hydroperoxide concentration, and by the mode of oxidant addition. The reaction scheme is rather complex, including, along with the desired reaction, also parallel and consecutive side processes. The catalyzed oxidation reaction to yield menadione is always accompanied by radical reactions leading to coupling products. The use of diluted hydrogen peroxide solutions (concentration 3.5 wt.%) favors the formation of these heavy compounds. On the other hand, in the presence of concentrated hydrogen peroxide solution (35 wt.%), the oxidation of the substrate to menadione occurs even without catalyst. High selectivity to menadione (i.e., 93%) is achieved only at the very beginning of the reaction when the substrate is added to the catalyst-containing hydrogen peroxide solution, the oxidant concentration being 35%. Under the latter conditions, the low concentration of substrate disfavors the undesired coupling reactions.

Novel X-ray imaging detectors based on photoluminescence of colour centres in lithium fluoride (LiF) have been proposed and tested for extreme ultraviolet, soft and hard X-rays up to 10 keV. For the first time we present the optical characterisation of LiF crystals and thin films irradiated at the TOPO-TOMO beamline of synchroton light source Anka (Karlsruhe, Germany) in the energy range 6-40 keV for different exposure times. Absorption and photoluminescence spectra were analysed to study the optical response of the LiF-based detectors. High resolved X-ray imaging of commercial test patterns has been obtained on LiF crystals and films by optical readout with a confocal laser scanning fluorescence microscope. © 2012 Elsevier B.V.

Objectives To date, Ficus carica L. cultivar Dottato (F. carica) has not been studied from a phototoxic point of view. In the present work, aerial components of F. carica from Italy, were examined to assess their antioxidant and phototoxic activity on human melanoma cells. A relationship between antioxidant, phototoxic activities and chemical composition has also been investigated. Materials and methods Coumarin and fatty acid content in F. carica leaves, bark and woody parts were examined and compared by capillary GC and GC/MS. Polyphenolic content was also determined. Linoleic acid peroxidation and DPPH test were used to assess antioxidant activities, and MTT assay was used to evaluate anti-proliferative activity, on C32 human melanoma cells, after irradiation with a UVA dose of 1.08 J/cm2. Results Leaves demonstrated the best antioxidant and anti-proliferative activity in comparison to bark and wood. In particular, leaves were shown to possess the highest anti-radical activity and inhibition of peroxidation, with IC50 values of 64 and 1.48 μg/ml respectively. The leaves had highest anti-proliferative activity with IC50 value of 3.92 μg/ml. The phytochemical investigation revealed different composition between the coumarins, psoralen and bergapten, fatty acids, polyphenols and flavonoid content among plant parts. Conclusions Data obtained indicate that this type of fig tree may constitute an excellent source of bioactive compounds, such as phenolics, coumarins and fatty acids. This study offers a new perspective in developing others formulations potentially useful in photodynamic therapy for treatment of non-melanoma skin cancers.

The main goal of the FAMU experiment is the measurement of the hyperfine splitting (hfs) in the 1S state of muonic hydrogen ΔE hfs (μ - p)1S. The physical process behind this experiment is the following: μp are formed in a mixture of hydrogen and a higher-Z gas. When absorbing a photon at resonance-energy ΔE hfs ≈ 0.182 eV, in subsequent collisions with the surrounding H 2 molecules, the μp is quickly de-excited and accelerated by ∼ 2/3 of the excitation energy. The observable is the time distribution of the K-lines X-rays emitted from the μZ formed by muon transfer (μp) + Z → (μZ)∗ + p, a reaction whose rate depends on the μp kinetic energy. The maximal response, to the tuned laser wavelength, of the time distribution of X-ray from K-lines of the (μZ)∗ cascade indicate the resonance. During the preparatory phase of the FAMU experiment, several measurements have been performed both to validate the methodology and to prepare the best configuration of target and detectors for the spectroscopic measurement. We present here the crucial study of the energy dependence of the transfer rate from muonic hydrogen to oxygen (Λ μp → μ0 ), precisely measured for the first time.

The high precision measurement of the hyperfine splitting of the muonic-hydrogen atom ground state with pulsed and intense muon beam requires careful technological choices both in the construction of a gas target and of the detectors. In June 2014, the pressurized gas target of the FAMU experiment was exposed to the low energy pulsed muon beam at the RIKEN RAL muon facility. The objectives of the test were the characterization of the target, the hodoscope and the X-ray detectors. The apparatus consisted of a beam hodoscope and X-rays detectors made with high purity Germanium and Lanthanum Bromide crystals. In this paper the experimental setup is described and the results of the detector characterization are presented., Comment: 22 pages, 14 figures, published and open access on JINST

Niobia–silica mesoporous materials (xerogel, aerogel and MCM type) have been synthesized by sol–gel techniques using different co-solvents as templates. All materials are active catalysts in the epoxidation of cyclohexene with hydrogen peroxide, but only meso–macroporous aerogels give a stable and recyclable catalyst.

The preparation of a series of niobium-based aerogel samples under acidic and basic conditions is reported. The effect of the matrix (SiO 2 , Al 2 O 3 , ZrO 2 ) and of the gelation conditions (acidic or basic) on the surface area, the porosity, and the catalytic activity of the solids in the oxidation of different substrates with hydrogen peroxide is investigated. The amount of niobium is constant in all samples. The oxidation of unsubstituted (cyclooctene) and substituted (geraniol, nerol, and trans-2-pentene-1-ol) olefins is studied. The catalysts are moderately active but produce epoxides in good yields. The latter are influenced by the matrix properties (surface acidity and surface area). The preparation method makes it possible to prepare catalysts that are resistant to leaching and can be recycled several times without appreciable loss of activity.

The preparation of a series of mesoporous tungsten oxide–silica mixed oxides by sol–gel methods under basic conditions is reported. Surface modification with methyl and 3-chloropropyl groups is possible in an amount between 10 and 40 mol% with respect to the silane precursor. The amount of polar organic functional groups controls the surface area, the porosity, and the catalytic activity of the solids in the oxidation of different substrates with hydrogen peroxide. The oxidation of geraniol is studied in detail. The catalysts are active and produce epoxides in good yields. The latter are influenced by the presence of polar organic groups. The preparation method allows the preparation of catalysts that are resistant to leaching and can be recycled several times without appreciable loss of activity.

The advent of scanning near-field optical microscopy (SNOM) has augmented at a microscopic level the usefulness of optical spectroscopy in the region between 300 nm and 10 mum. Two-dimensional imaging of chemical constituents makes this a very attractive and powerful new approach. In this paper we show SNOM results obtained in several geometrical configurations on boron clusters in silicon, Li clusters embedded in a LiF sample and BN growth on silicon. We also show some results on the wavelength dependence of the reflectivity (R) in the near infrared (IR) of biological cells in liquid environment with the observation of the local fluorescence. The SNOM images revealed features that were not present in the corresponding shear-force (SF) images and which were due to localized changes in the bulk properties of the sample. The size of the smallest detected features clearly demonstrated that near-field conditions were reached both in the visible and infrared region. (C) 2004 Elsevier B.V. All rights reserved.

Sulphated zirconia (SZ) was synthesized under different precipitation and ageing conditions. Catalysts were characterized by nitrogen adsorption–desorption, thermal analysis, FTIR and Raman spectroscopy. The catalytic performance of these SZ systems in both gas and liquid-phase reactions has been investigated. The effect of precipitation and ageing conditions has been studied and a correlation with catalytic activity has been tried.

Aim This prospective study on teeth with necrotic pulps evaluated the clinical outcome of root canal treatments performed with two full-length Ni-Ti rotary file systems with different cross-sectional design and canal-cleaning ability. Methodology Ninety-four patients with necrotic pulps, and periapical lesions needing root canal treatment were included and randomly divided into two groups. At baseline, a preliminary periapical radiograph was taken and the presence of pain was registered according to the Verbal Rating Scale. A single operator performed all single-visit root canal treatments under rubber dam isolation; when necessary, pre-endodontic restorations were provided. Canals were instrumented with Mtwo (Sweden & Martina, Italy) (Group 1, n = 55) or Alpha Kite (Komet, Germany) (Group 2, n = 39), irrigated with 2.5% NaOCl and filled by the continuous wave of condensation technique (System B; SybronEndo, USA). No chelating agents were used during irrigation. Coronal seal was assured by immediate direct composite restorations. Patients were recalled after 6 months to repeat clinical and radiographic evaluations. Statistical analysis was performed using chi-square, McNemar, Mann–Whitney, Wilcoxon tests (SPSS Inc., USA) (P < 0.05). Results Complete periapical healing was observed in 55% and 51% of cases in Group 1 and Group 2 respectively. Subtotal reduction of periapical radiolucencies occurred in 40% of patients in Group 1 and 49% in Group 2. Almost all symptoms disappeared at 6-month follow-up in both groups. No significant differences were found between the groups in any of the parameters considered (P > 0.05). Conclusions Within the limits of the present study, the use of M two and Alpha Kite instruments produced similar success rates at 6-month follow-up.

Electron-beam lithography has been used to define color center stripes of about one hundred micrometers length and variable width (100 nm to 5 μm) in lithium fluoride. These structures have for the first time been illustrated and spectrally characterized in near field optical microscopy (SNOM) operating in local illumination mode with an optical fiber probe and far field fluorescence detection.

A three-dimensional solute transport model was developed and linked to a three-dimensional transient model for soil water flow and root growth. The simulation domain is discretized into a grid of finite elements by which the soil physical properties are spatially distributed. Solute transport modeling includes passive and active nutrient uptake by roots as well as zero- and first-order source/sink terms. Root water uptake modeling accounts for matric and osmotic potential effects on water and passive nutrient uptake. Root age effects on root water and nutrient uptake activity have been included, as well as the influence of nutrient deficiency and ion toxicity on root growth. Examples illustrate simulations with different levels of model complexity, depending on the amount of information available to the user. At the simplest level, root growth is simulated as a function of mechanical soil strength only. Application of the intermediate level with root water and nutrient uptake simulates the influence of timing and amount of NO3 application on leaching. The most comprehensive level includes simulation of root and shoot growth as influenced by soil water and nutrient status, temperature, and dynamic allocation of assimilate to root and shoot.

The platform switching concept involves the reduction of the restoration abutment diameter with respect to the diameter of dental implant. Long-term follow up around these wide-platforms showed higher levels of bone preservation.The aim of this article is to carry out a literature review of studies which deal with the influence of platform-switched implants in hard and soft oral tissues.All papers involving "platform switching" that are indexed in MedLine and published between 2005 and 2011 were used. Clinical cases, experimental and non-experimental studies were included, as well as literature reviews.In our search, we analized 18 clinical cases and 3 reviews. The results indicate that peri-implant bone resorption is reduced with platform switching system.All papers written by different researchers show an improvement in peri-implant bone preservation and satisfactory aesthetic results. Further long-term studies are necessary to confirm these results.

To compare in vivo three different electronic root canal length measurement devices: Dentaport ZX, Raypex 5 and ProPex II.Thirty single-rooted permanent teeth scheduled for extraction because of periodontal disease were selected from 10 adult patients (ranging from 45 to 67 years) and divided into three groups of 10 teeth. Before the extraction, an access cavity was prepared and the crown was adjusted to establish a stable reference point for all measurements. The working length in Group 1 was determined using the Dentaport ZX apex locator. A K-file with the largest diameter that could reach the last green bar on the screen was stabilized in the canal using a dual-curable flow resin composite. The same procedure was used for the Raypex 5 (the file reached the last yellow bar) and Propex II (0.0 orange bar) apex locators. The teeth were then extracted and cleared. The distance between the tip of the file and the major foramen was then calculated for each tooth using digital photography according to Axiovision AC software (Carl Zeiss). Positive values were assigned when the file tip passed beyond the major foramen, negative values when the tip was short of the foramen and zero value when the file tip and the foramen coincided. Statistical analysis was performed using the chi-squared test or Fisher's exact test (P ≤ 0.05). Dentaport ZX, Raypex 5 and ProPex ΙΙ produced, respectively, 6, 2 and 4 out of 10 correct measurements, 0, 6 and 5 long measurements and 4, 2, and 1 short measurements. The differences between the three electronic root canal length measurement devices were not significant (P = 0.507).Under the in vivo conditions of this study, the three electronic root canal length measurement devices were not significantly different in terms of locating the major foramen.

At present, the focal infection theory still has very controversial aspects. In spite of the great number of studies, there is no evidence that focal infections or even antigenic mimicry are responsible for anything other than sporadic abscesses/infections and possibly rare autoimmune disorders. linflammation of endodontic origin (i.e., apical periodontitis--AP) has not received the same attention as inflammation originating from the periodontium. Endodontics is a microbiological problem, since the bacterial infection is the "prime mover" of pulp (before) and periapical (later) disease. The aims of endodontic treatment have to be considered from a microbiological viewpoint. Considering these problems in this second part of their study, the Authors, after close examination of the virulence of microorganisms and of the host defense, analyze the endodontic infection and microbiological species. They emphasize the possibility of a relationship between periapical inflammatory lesions and bacterial endocarditis in preventing metafocal disease. Bacterial endocarditis deserves special mention because despite involving specialists of two scientific fields, its prophylaxis is almost always assigned to medical practice, and especially, to dentistry. Given the dangers of the disease, antibiotic prophylaxis is both absolutely necessary and can be very effective, and it should be used especially in clinical situations with high risk individuals. However, the ability of antibiotic therapy to prevent or reduce the frequency, magnitude or duration of bacteremia associated with a dental procedure is controversial. Studies should also be undertaken to determine to compare the efficacy of endodontic treatment with alternative therapy such as implants, prosthetic replacements or no treatment other than extraction. To date, these studies have not been carried out, and there is no evidence to support the theory that modern endodontic therapy is not safe and effective.

The aim of this study was to investigate the presence and the role of the parathyroid hormone-related protein (PTH-rP) in the inflamed pulp.Thirty-four pulp tissue specimens (24 inflamed and 10 normal pulps) from extracted third molars were studied. The presence of PTH-rP was observed by using immunohistochemistry. Negative controls were performed using non immunized rabbit or mouse serum, omitting the primary antibody.The analysis of all the sections of normal pulps showed the presence of PTHrP positive cells only in the odontoblastic zone and in few fibroblasts. Instead all inflamed pulps showed PTHrP positive cells both in vascular zone and in pulp stroma, as well as in the odontoblastic and subodontoblastic zone.Several works proved that this peptide plays a role even in angiogenesis process, but its function is controversial. It is possible to hypothesize that PTHrP stimulates angiogenesis, but it is recommended to further conduct research on this area.

A series of sulphated zirconia (SZ) samples were prepared by the liquid-crystal templating (LCT) method, using linear alcohols with different alkyl chain length as co-solvents and neutral ammine as template. The type and duration of aging was also varied in order to study their effects on the catalytic activity and texture of the synthesized catalysts. These materials were characterized by ion chromatography for determination of sulphate content, nitrogen-adsorption measurements, X-ray diffraction, and transmission electron microscopy. The results showed that the sulphated zirconia catalysts were mesoporous and that their surfaces area and pore size distribution varied as a function of the synthesis conditions. In particular, we found a direct correlation between alkyl chain length of co-solvent and the pore size. The catalytic activity was tested in the toluene and anisole acylation and it was found to increase with the pore size.

Niobia–silica mixed oxides can be synthesized under acidic conditions and evaporated under supercritical conditions to yield meso-macroporous materials. The amount of active metal in the catalyst changes the acidity of the final material and in the epoxidation of allylic alcohols (geraniol) a high amount of niobium improves the production of glycols. Surface modification with methyl groups is possible by addition of methyltriethoxysilane without any change in the morphological properties of the final materials. The extent of methylation does not change significantly the surface area and the porosity but does change the catalytic activity of the materials in the epoxidation of the cyclooctene and geraniol. Methylation improves the activity of the catalysts and the use of the oxidant in the epoxidation of unsubstitued olefins, whereas only small differences were observed in the epoxidation of geraniol.

Sulfated zirconia samples having a variable Ga 2 O 3 content (in the 1–15% molar range) were synthesized. The promoting effect of gallium was studied in the catalytic isomerization of n -butane at 523 K, by feeding n -butane and H 2 (with a 1:4 ratio). Catalytic activity was found to be greatly dependent on gallium loading. Catalysts containing 3–5 mol% Ga 2 O 3 doubled the activity of sulfated zirconia, whereas for a sample with 15 mol% Ga 2 O 3 the catalytic activity was completely lost. Surface chemistry of these materials was studied by means of FTIR spectroscopy and adsorption microcalorimetry, using selected probe molecules (CO and 2,6-dimethylpyridine). IR spectroscopy showed that gallium-containing sulfated zirconia samples exhibit both Lewis and Bronsted acidity. Lewis acidity is attributed to coordinatively unsaturated Zr 4+ ions located in defective surface sites, whereas Bronsted acidity is associated to surface sulfate groups. Samples with a Ga 2 O 3 content between 1 and 9 mol% show a combination of Lewis and Bronsted acidity that quantitatively decreases with increasing gallium oxide content. Samples having a Ga 2 O 3 content equal to 9 mol% or greater show the following specific features: (i) these samples are much more difficult to dehydrate than those with smaller gallium content, and the hydroxy groups interact by hydrogen bonding, (ii) the sulfate groups progressively lose their covalent character, and (iii) both Lewis and Bronsted acidity of the samples decreases drastically. Couples of Lewis and Bronsted acid sites appear to be needed for catalytic activity in n -butane isomerization, and they present an optimum ratio when the catalyst is brought to a medium-high dehydration degree and when its Ga 2 O 3 content is of about 3–5 mol%.

Scanning near-field optical microscopy (SNOM) makes it routinely possible to overcome the fundamental diffraction limit of standard (far-field) microscopy. Recently, aperture-based infrared SNOM performed in the spectroscopic mode, using the Vanderbilt University free electron laser, started delivering spatially-resolved information on the distribution of chemical species and on other laterally-fluctuating properties. The practical examples presented here show the great potential of this new technique both in materials science and in life sciences. (C) 2004 Elsevier B.V. All rights reserved.

This paper presents the results of a research aiming at evaluating the effects of storage on wastewater characteristics. Wastewater discharged from the Caltagirone (Eastern Sicily) plant after secondary treatment was stored in an earth reservoir with a capacity of about 25,000 m3 and a depth of 5 m. Wastewater inflow in the reservoir was continuous throughout the experimental activities, while discharge was discontinuous, depending on irrigation demand. Removal efficiency resulted highly influenced by the operation regime of the reservoir and by influent wastewater characteristics. BOD5 and COD removal efficiency was above 50%. Removal efficiency of faecal coliforms, faecal streptococci and Escherichia coli was between 2 and 5 log units. Single and multiple regressions were tested to determine the reservoir design characteristics and operation parameters that most significantly affected water quality changes.

The measured room-temperature absorption spectra of LiF crystals implanted with 1.5 MeV He+ ions at different ion doses are presented. The application of a theoretical model allowed us to give an estimation of the band intensities associated with various kinds of electronic defects and to study their dependence on the ion dose. The model also considers the contribution due to narrometric lithium colloids, whose formation starts in the dose range at which the production of colour centres saturates.

Lithium fluoride (LiF) films irradiated by low energy electrons were employed as active spacers in all-solid, dielectric optical microcavities emitting in the visible spectral range. We present the results of optical characterization of the spontaneous emission from F 2 color centers embedded in a LiF layer confined inside a planar microcavity. These structures seem promising for the realization of novel kinds of solid-state miniaturized emitting devices.

Recently the ternary compound CsPbCl/sub 3/ produced by co-evaporating CsCl and PbCl/sub 2/ has attracted much interest for its interesting optical characteristics. Indeed, aggregates with dimensions of about 10 nm are produced in the material as evidenced by luminescence spectroscopy and X-ray diffraction. Identification of the aggregates is based on a similarity of the observed emission properties with those of the bulk material. CsPbCl/sub 3/ is a wide-gap semiconductor with direct band-to-band transitions. The phase diagram of the CsCl-PbCl/sub 2/ system reveals the existence of complex ternary CsPbCl/sub 3/ (phase III semiconductor) and Cs/sub 4/PbCl/sub 6/ (phase VI, insulator) compounds. Varying the deposition rate the phase III is deposited together with the insulating phase VI. The crucible temperatures have also been optimized to control the deposition rate in order to achieve the ternary phase III only. The aim of this paper is to report on the preparation, optical and electrical characteristics of bulk and vacuum evaporated ternary compounds. To our knowledge this is the first time that the electrical behaviour in dark and in light is reported for these compounds. The correlation of the aggregate dimensions with the exciton absorption will be also introduced and discussed. X-ray diffraction spectroscopy is used as an independent evidence for aggregated phase creation. Samples used for this study have been grown by vacuum evaporation starting from Bridgman crystal chips of CsPbCl/sub 3/ or by co-evaporation of CsCl and PbCl/sub 2/ purified powders onto 7059 Coming glass substrates.

This paper presents the results of a research aiming at evaluating the effects of storage on wastewater characteristics. Wastewater discharged from the Caltagirone (Eastern Sicily) plant after secondary treatment was stored in an earth reservoir with a capacity of about 25,000 m3 and a depth of 5 m. Wastewater inflow in the reservoir was continuos throughout the experimental activities, while discharge was discontinuous, depending on irrigation demand. Removal efficiency resulted highly influenced by the operation regime of the reservoir and by influent wastewater characteristics. BOD5 and COD removal efficiency was above 50%. Removal efficiency of faecal coliforms, faecal streptococci and Escherichia coli was between 2 and 5 log units. Single and multiple regressions were tested to determine the reservoir design characteristics and operation parameters that most significantly affected water quality changes.

To analyze the factors associated with mortality, survival and causes of death in patients with systemic lupus erythematosus (SLE) in Argentina.A series of 366 patients with SLE (45 men and 321 women), mean age 29 y (range 11-70 y) and mean disease duration 6 y, was evaluated from 1990 to 1998. A total of 57 clinical, serological and therapeutic variables were studied.Five- and 10-year survival was 91% and 85% respectively. Forty four patients died (12%): 54% due to sepsis and 32% due to active SLE. Mortality risk factors included heart involvement CRR 3.82), hyperlipidemia (RR 2.72), renal damage (RR 2. 62), infections (RR 2.44), lung disease (RR 2.20) and myositis (RR 2. 07). High-dose prednisone (RR 3.4) or cyclophosphamide (RR 9.19) treatments increased the risk of sepsis (P=0.003) as a cause of death. However, corticosteroids, antimalarial agents and accumulated cyclophosphamide doses proved to be protective factors in overall mortality figures (RR1).The main risk factors of death in SLE were heart involvement, hyperlipidemia and renal damage. Treatment with steroids, antimalarial agents and cyclophosphamide improved survival. High-dose corticosteroids and cyclophosphamide were associated with sepsis as a cause of death.

In order to accurately assess the occurrence, extent and severity of a drought it is necessary to get a correct picture of the spatial and temporal distribution of a number of meteorological, hydrological and surface variables. Space observations have the potential to make a significant contribution in this field. Due to the capability to retrieve surface parameters with high spatial and temporal resolutions over large areas, a comprehensive view of the situation can be obtained. The satellite sensor measures, however, radiation fields and the conversion of these measurements into surface parameters and further into information regarding drought conditions needs sophisticated analysis tools.

We report fluorescence imaging of colour centres in Lithium Fluoride (LiF) using an apertureless Scanning Near Field Optical Microscope (SNOM). The sample consists of periodically spaced submicrometric coloured areas F-2 laser-active colour centres produced by low-energy electron beam lithography on the surface of a LiF thin film. A silicon Atomic Force Microscope (AFM) tip is used as an apertureless optical probe. AFM images show a uniform surface roughness with a RMS of 7.2 nm. The SNOM images of the red fluorescence of colour centres excited at lambda =458 nm with an argon ion laser show that the local photon emission is unambiguously related to the coloured areas and that topographic artefacts can be excluded. (C)2001 Optical Society of America.

Temperature-modulated absorption spectra of SbSI near the ferroelectric-paraelectric phase transition are reported. The experiment was performed using unpolarized light. The modulation technique allows a more precise and univocal determination of the energy gap E o and its temperature dependence, which has been evaluated by means of a phenomenological interpretation of the experimental lineshapes. A direct explanation is also provided for the already known typical dependence on temperature of the amplitude of modulation spectra at band gap energy.

A technique is described which allows a direct determination of the temperature dependence of the refractive index of transparent liquids and solids. It consists of an interferometric examination of a liquid or solid whose temperature changed in time linearly. For all the tested liquids except water, delta n/ delta t was found to be constant in the range 25-60 degrees C. The values delta n/ delta t determined for H2O, C6H12 and CCl4, and the value of delta 2n/ delta t2 obtained for water, are in good agreement with literature.

A direct determination of the temperature dependence of the refractive index of water has been performed in the range -3 degrees to +80 degrees C. In this range delta n/ delta t shows an exponential behaviour. Attempts have been made to obtain a relation between delta n/ delta t and the molecular polarisability of water.

In this paper we present and discuss some recent experimental results obtained on SbSI by thermomodulating its absorption coefficient in the forbidden gap energy region at the first (∼293 K) and second (∼230 K) phase transition. The characteristic lineshapes of the temperature modulated optical spectra are also discussed, both from a phenomenological point of view and through the evaluation of the exact first-derivative expressions of the modulated dielectric function.

The temperature coefficient of the refractive index, (∂n/∂T)p, has been measured for deuterium oxide. The observed values are considered together with those previously obtained for water. The experimental data cannot be explained with the best known models of molecular polarizability, at least in the approximation generally used in these models. Therfore they are discussed on the basis of a different approximation, suggested by a well-known structural model of liquid water. It is shown that the experimental results are very well explained, in a wide range of temperature, with the hypothesis of the existence of "structural voids".

Crystals of undoped and OH− doped KBr have been γ−rays irradiated at room temperature. Colouring curves of doped samples show bleaching effects at high absorbed energy doses. This result is interpreted in terms of a reaction between the OH− impurities and the formed F centres which predominates on the enhancement of the colouration due to the excess of anion vacancies induced by the OH− defects.

Thermoreflectance spectra in the exciton region were obtained on the layer compound GaSe. The experimental results can be explained by assuming that the only temperature effect is a shift of the whole structure. At liquid nitrogen temperature the values Eo = 2.093 eV and T = 41.0 meV are found for the first energy level and the broadening parameter, respectively. Measurements at three different temperatures gave the value dE0/dT = −5.49 × 10−4 eV/deg for the temperature coefficient. On a mesure les spectres de thermoreflectivite du compose lamellaire GaSe dans la region excitonique. Les resultats des experiences peuvent ětre expliques par un deplacement des structures seulement. A la temperature de l'azote liquide on a trouve pour le premier niveau d'energie et pour le parametre d'elargissement les valeurs E0 = 2,093 eV, et T = 41,0 meV. Par des mesures a trois temperatures differentes nous avons obtenu pour le coefficient thermique la valeur dE0/dT = −5,49 × 10−4 eV/deg.