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Corrections for scattering on XRF intensity have commonly used integral approaches and isotropic approximations, which give a limited knowledge on this subject. An exact theoretical expression for XRF enhancement due to coherent and incoherent scattering is presented in this paper. It has been obtained as a solution of the Boltzmann transport equation for photons. This equation describes the diffusion of photons in an infinite homogeneous target. Both the excitation and the emission beams have been assumed to be well collimated. The solution accounts for the mixed, scattering and photoelectric interactions. Complete kernels including atomic form factors have been used for both types of scattering. An appropriate kernel has been written for the photoelectric interaction. The correction is computed for several pure elements and is compared with isotropic approximations.
A theoretical expression for the fourth-order XRF-intensity has been found using the transport theory. An exact solution of the Boltzmann equation for the photon flux in a semi-infinite homogeneous medium has been applied iteratively to find the intensity, XRF emission has been isolated from the scattering processes by considering only the photoelectric effect in the interaction kernel. The incident and emitted beams have been assumed as well-collimated.
Fourth-order intensity computations for a multicomponent material are reported as an example. Results show that the fourth-order intensity remains below a tenth of the tertiary and therefore may be neglected in most cases.
In the current data-driven science era, it is needed that data analysis techniques has to quickly evolve to face with data whose dimensions has increased up to the Petabyte scale. In particular, being modern astrophysics based on multi-wavelength data organized into large catalogues, it is crucial that the astronomical catalog cross-matching methods, strongly dependant from the catalogues size, must ensure efficiency, reliability and scalability. Furthermore, multi-band data are archived and reduced in different ways, so that the resulting catalogues may differ each other in formats, resolution, data structure, etc, thus requiring the highest generality of cross-matching features. We present C3 (Command-line Catalogue Cross-match), a multi-platform application designed to efficiently cross-match massive catalogues from modern surveys. Conceived as a stand-alone command-line process or a module within generic data reduction/analysis pipeline, it provides the maximum flexibility, in terms of portability, configuration, coordinates and cross-matching types, ensuring high performance capabilities by using a multi-core parallel processing paradigm and a sky partitioning algorithm.
The VIALACTEA project brings to a common forum the major new-generation surveys of the Milky Way Galactic Plane from 1μm to the radio, both in thermal continuum and in atomic and molecular lines, to attack in a systematic way the characterization of the Milky Way as a star formation engine. Images, catalogues, spectroscopic datacubes and radiative transfer models of the Spectral Energy Distributions (SEDs) of sites of star formation have been incorporated and indexed in the VIALACTEA Knowledge Base (VLKB). The VLKB consists of a combination of a relational database where the VIALACTEA data and metadata are homogenised and stored, and a filesystem-based stored information. This infrastructure allowed, among others, the generation of extensive catalogue for compact sources and extended structures in the Galactic Plane, the implementation of data-mining algorithms for the band-merging of multiwavelength data and expert systems for the automated analysis of molecular line surveys to extract critical kinematical information and derive distances using Galaxy rotation curves and new 3D extinction maps. A new VIALACTEA 3D Visual Analytics interface has been developed that provides integrated access and analysis of continuum and spectroscopic images together with catalogue data directly interfacing with the VLKB.
REM (Rapid Eye Mount) is a fully robotized fast slewing telescope equipped with a high throughput Near InfraRed (Z′, J, H, K′) camera (REMIR) and an optical slitless spectrograph (ROSS). A dedicated software for data reduction and software (AQuA) has been developed to extract scientific information from REM images without any human intervent. REM is installed in La Silla (Chile) and dedicated to detect and study the prompt optical/IR afterglow of Gamma Ray Bursts with the ambitious project of discovering objects at extremely high redshift. The synergy between REMIR camera and ROSS makes REM a powerful observing tool for any kind of fast transient phenomena.
The Evolutionary Map of the Universe (EMU) is a proposed radio continuum survey
of the Southern Hemisphere up to declination + 30°, with the Australian
Square Kilometre Array Pathfinder (ASKAP). EMU will use an automated source
identification and measurement approach that is demonstrably optimal, to
maximise the reliability and robustness of the resulting radio source
catalogues. As a step toward this goal we conducted a “Data
Challenge” to test a variety of source finders on simulated images. The
aim is to quantify the accuracy and limitations of existing automated source
finding and measurement approaches. The Challenge initiators also tested the
current ASKAPsoft source-finding tool to establish how it could benefit from
incorporating successful features of the other tools. As expected, most finders
show completeness around 100% at ≈ 10σ dropping to about 10% by
≈ 5σ. Reliability is typically close to 100% at ≈
10σ, with performance to lower sensitivities varying between finders. All
finders show the expected trade-off, where a high completeness at low
signal-to-noise gives a corresponding reduction in reliability, and vice versa.
We conclude with a series of recommendations for improving the performance of
the ASKAPsoft source-finding tool.
The Camberwell Assessment of Need – Forensic Version (CANFOR) is a standardised assessment tool specifically designed to assess needs for care in forensic psychiatric populations. The original English version of the instrument has shown good psychometric properties. The aim of this study was to validate the Italian version of the CANFOR-staff tool.
After translation and back-translation, the Italian CANFOR tool was administered to a sample of 50 forensic psychiatric patients. Convergent validity was tested using the Brief Psychiatric Rating Scale (BPRS) and the Global Assessment of Functioning (GAF) by applying Kendall's tau-b. Inter-rater and test–retest reliabilities were measured by ICCs for need dimensions (total and unmet) and Cohen's kappa coefficients for individual need items.
Regarding convergent validity, a higher number of needs (total and unmet) were associated with more severe psychiatric symptoms (BPRS). Higher numbers of unmet needs were also associated with lower levels of global functioning (GAF). ICCs for total and unmet needs scores indicated a good level of agreement for inter-rater reliability and a very good level for test–retest, respectively. Regarding the specific items, inter-rater Cohen's kappa was high (moderate to very good agreement) for 18 items in relation to the presence of a need and for 15 items in the rating of an unmet need, whereas Cohen's kappa for test–retest reliability was very high for all the items in the presence of a need and high for 18 of the unmet need domains.
The Italian version of CANFOR has adequate psychometric properties. It can be considered a promising instrument for the assessment of needs of forensic psychiatric patients.
The response of Grapholita molesta (Busck) males to three-component sex pheromone blends containing a 100% ratio of the major sex pheromone component, (Z)-8-dodecenyl acetate and a 10% ratio of (Z)-8-dodecenol, but with varying ratios of (E)-8-dodecenyl acetate (0.4, 5.4, 10.4, 30.4, and 100.1% E-blends) was tested with populations in eight stone and pome fruit orchards in Europe, Asia, and North and South America. Traps baited with the 5.4% E-blend caught significantly more males than traps with any other blend with all populations. Significantly more males were caught in traps baited with the 10.4% E-blend than in traps with the remaining blends, except with the 0.4% E-blend in Turkey. Significant differences in male moth catches occurred between the other blends with the 0.4>30.4% E-blend, and the 30.4>100.1% E-blend. Male moth catches with the 100.1% E-blend only differed from the hexane control in Chile. No apparent differences were noted to these blends in populations collected from pome or stone fruits. Flight tunnel assays to synthetic blends with a subset of populations were similar to the field results, but the breadth of the most attractive E-blends was wider. Flight tunnel assays also demonstrated a high level of male–female cross-attraction among field-collected populations. Female gland extracts from field-collected populations did not show any significant variation in their three-component blends. The only exceptions in these assays were that long-term laboratory populations were less responsive and attractive, and produced different blend ratios of the two minor components than recently collected field populations.
Human milk proteins provide term and preterm infants with both nutrition and protection. The objective of the present study was to examine longitudinal changes in the protein composition of term and preterm milk during the first 2 months of lactation, focusing on protein phosphorylation and glycosylation. Using gel electrophoresis, the relative concentration and glycosylation status of lactoferrin, secretory Ig A, β-casein, α-lactalbumin, serum albumin, bile salt-stimulated lipase, xanthine oxidoreductase, tenascin and macrophage mannose receptor 1 were measured in milk collected on days 7, 10, 14, 18, 21, 28 and 60 postpartum from preterm mothers (28–32 weeks gestation, n 17). The phosphorylation status of β-casein was also investigated. To determine if these variables differ in term and preterm milk, samples from term mothers (38–41 weeks gestation, n 8) collected on days 7, 14 and 30 of lactation were also analysed. The concentration of the abundant milk proteins decreased during lactation in term and preterm milk (P <0·05). No difference in protein glycosylation was observed, except for the glycoproteins serum albumin and tenascin. The phosphorylation of β-casein varied significantly between term and preterm milk. Further investigation is required to determine whether these modifications affect protein function and are clinically important to preterm infants.
On the basis of well-known literature, an analytical tool named LEAF (linear elastic analysis of fracture) was developed by the authors to predict the damage tolerance (DT) proprieties of aeronautical stiffened panels. The tool is based on the linear elastic fracture mechanics and the displacement compatibility method. By means of LEAF, an extensive parametric analysis of stiffened panels, representative of typical aeronautical constructions, was performed to provide meaningful design guidelines. The effects of riveted, integral and adhesively bonded stringers on the fatigue crack propagation performances of stiffened panels were investigated, as well as the crack retarder contribution using metallic straps (named doublers) bonded in the middle of the stringers bays. The effect of both perfectly bonded and partially debonded doublers was investigated as well. Adhesively bonded stiffeners showed the best DT properties in comparison with riveted and integral ones. A great reduction of the skin crack growth propagation rate can be achieved with the adoption of additional doublers bonded between the stringers.
We study coupled semiconductor quantum dots theoretically using a generalized Hubbard approach, where intra- and inter-dot Coulomb correlation, as well as tunneling effects are described on the basis of realistic electron wavefunctions. We find that the ground-state configuration of vertically coupled double dots undergoes non-trivial quantum transitions as the inter-dot distance d changes; at intermediate values of d we predict a new phase that should be observable in the addition spectra and in the magnetization changes.
The deformation of copper with grain size less than 10 nm is investigated using a 2D continuum model incorporating atomistically-based constitutive relations. The local constitutive response of a series of symmetric and asymmetric tilt grain boundaries is obtained using an atomistic quasicontinuum method under tension and shear. The atomistic results show that it is possible to associate a constant maximum stress with each deformation mechanism triggered in the GB vicinity, i.e. GB sliding and decohesion, atom shuffling and partial dislocation emission. The GB strength is always found weaker in shear than in tension. This information is incorporated into a continuum polycrystalline model tested under compression. This model provides useful insights, in the absence of intragranular plasticity, into the onset of macroscopic quasi-plasticity, which results from GB sliding and collective grain rotation mechanisms.
We retrospectively studied patients diagnosed with P. aeruginosa bloodstream infections (BSIs) in two Italian university hospitals. Risk factors for the isolation of multidrug-resistant (MDR) or non-MDR P. aeruginosa in blood cultures were identified by a case-case-control study, and a cohort study evaluated the clinical outcomes of such infections. We identified 106 patients with P. aeruginosa BSI over the 2-year study period; 40 cases with MDR P. aeruginosa and 66 cases with non-MDR P. aeruginosa were compared to 212 controls. Independent risk factors for the isolation of MDR P. aeruginosa were: presence of central venous catheter (CVC), previous antibiotic therapy, and corticosteroid therapy. Independent risk factors for non-MDR P. aeruginosa were: previous BSI, neutrophil count <500/mm3, urinary catheterization, and presence of CVC. The 21-day mortality rate of all patients was 33·9%. The variables independently associated with 21-day mortality were presentation with septic shock, infection due to MDR P. aeruginosa, and inadequate initial antimicrobial therapy.
This article examines the features of a labor market in which there are two professional groups that both cooperate and directly compete with each other: certified registered nurse anesthetists (CRNAs) and anesthesiologists (MDAs). We examine how the relative numbers of these two types of anesthesia providers, and differences in regulation, affect the earnings of CRNAs, and the extent of supervision of CRNAs by MDAs. We find that both the earnings, and the likelihood of medical supervision of CRNAs, are closely determined by their market share. As the market share of CRNAs increases from 0% to 50%, the gains to MDAs from restricting competition increase; over this range the likelihood that CRNAs are supervised increases and their expected earnings decline. However, as the CRNAs’ market share increases beyond 50%, the costs to MDAs of anticompetitive measures become too large, therefore, the probability of supervision declines, and the earnings of CRNAs increase.
Background: Workforce shortages to meet the mental health needs of the world's aging population are well documented. Within the field of professional geropsychology in the U.S.A., a national conference was convened in 2006 to delineate competencies for psychological practice with older adults and a training model for the field. The conference produced the Pikes Peak Model of Geropsychology Training. The Council of Professional Geropsychology Training Programs (CoPGTP) aimed to produce a competency evaluation tool to help individuals define training needs for and evaluate progress in development of the Pikes Peak professional geropsychology competencies.
Methods: A CoPGTP task force worked for one year to adapt the Pikes Peak Model geropsychology attitude, knowledge, and skill competencies into an evaluation tool for use by supervisors, students and professional psychologists at all levels of geropsychology training. The task force developed a competency rating tool, which included delineation of behavioral anchors for each of the Pikes Peak geropsychology knowledge and skill competencies and use of a developmental rating scale. Pilot testing was conducted, with 13 individuals providing feedback on the clarity and feasibility of the tool for evaluation of oneself or students.
Results: The Geropsychology Knowledge and Skills Assessment Tool, Version 1.1, is now posted on the CoPGTP website and is being used by geropsychology training programs in the U.S.A.
Conclusions: The evaluation tool has both strengths and limitations. We discuss future directions for its ongoing validation and professional use.
Thermodynamic properties and compositions of gases in thermal equilibrium at high temperature can in principle be derived quite accurately once the partition functions of the relevant species have been calculated.
AMICA (Antarctic Multiband Infrared CAmera) is an instrument designed to perform astronomical
imaging in the near- (1-5 μm) and
mid- (5–27 μm) infrared wavelength regions. Equipped with two detectors, an InSb 2562 and a Si:As 1282 IBC,
cooled at 35 and 7 K respectively, it will be the first instrument to investigate the potential of the Italian-French
base Concordia for IR astronomy.
The main technical challenge is represented by the extreme conditions of Dome C
(T ~ -90 °C, p ~ 640 mbar). An environmental control system
ensures the correct start-up, shut-down and housekeeping of the various components of the camera.
AMICA will be mounted on the IRAIT telescope and will perform survey-mode
observations in the Southern sky. The first task is to provide important site-quality data. Substantial
contributions to the solution of fundamental
astrophysical quests, such as those related to late phases of stellar evolution and to star formation processes, are also