237 research outputs found
Studio mediante spettroscopia in riflettanza non invasiva dei pigmenti utilizzati dal pittore Federico Zandomeneghi sul dipinto "Bastimento allo scalo" (Galleria d’Arte Moderna di Firenze Palazzo Pitti)
La tecnica impiegata per la caratterizzazione del materiale pittorico si basa sull’analisi di spettri di riflettanza acquisiti in maniera non invasiva. Con questo termine (spettri di riflettanza), si definiscono grafici in cui l’intensità della radiazione retro-diffusa dalla superficie investigata è riportata sull’asse delle ordinate in funzione della lunghezza d’onda della radiazione inviata sull’area di misura. Il valore dell’intensità, riportato come percentuale di luce diffusa (riflessa) dalla superficie investigata, è rapportato ad un bianco di riferimento, che si assume diffondente la radiazione incidente al 100% su tutto l’intervallo spettrale considerato
Forensic botany as a useful tool in the crime scene: report of a case
The ubiquitous presence of plant species makes forensic botany useful for many criminal cases. Particularly, bryophytes are useful for forensic investigations because many of them are clonal and largely distributed. Bryophyte shoots can easily become attached to shoes and clothes and it is possible to be found on footwear, providing links between crime scene and individuals. We report a case of suicide of a young girl happened in Siena, Tuscany, Italia. The cause of traumatic injuries could be ascribed to suicide, to homicide, or to accident. In absence of eyewitnesses who could testify the
dynamics of the event, the crime scene investigation was fundamental to clarify the accident. During the scene analysis, some fragments of Tortula muralis Hedw. and Bryum capillare Hedw were found. The fragments were analyzed by a bryologists in order to compare them with the moss present on the stairs that the victim used immediately before the death. The analysis of these bryophytes found at the crime scene allowed to reconstruct the accident. Even if this evidence, of course, is circumstantial, it can be useful in forensic cases, together with the other evidences, to reconstruct the dynamics of events
GC/MS analysis of morning glory seeds freely in commerce: can they be considered "herbal highs"?
Abstract Background The so-called "herbal highs" are substances derived from natural plants with effects on the central nervous system. Lisergamide, ergine or LSA is the basis of different types of drugs, which are in seeds of Ipomoea violacea, also known as Morning Glory, and other seeds. In our study we analysed the presence of lysergic acid amide (LSA) in seeds of Ipomoea violacea seized by the Italian Police, in others purchased through the Internet, and in other varieties of Ipomoea sold for ornamental purposes, to assess whether the actual consumption of ornamental seeds could contain hallucinogenic doses of LSA. Methods The analyses were conducted at the Laboratory of Forensic Toxicology of the Section of Legal Medicine of the University of Perugia, using GC/MSD system. For analysis, 300 mg of seeds (~8 seeds) from each specimen were chosen. Results Analysis revealed that 300 mg of Ipomoea violacea seeds resulting from police seizures, equivalent to approximately 8 seeds, contained a percentage of LSA equal to 0.062%. This finding is in agreement with what was indicated in literature, as the ingestion of 250 seeds would lead to a dose of approximately 6 mg of LSA, capable of provoking hallucinogenic effects. The analysis of 300 mg of Ipomoea Rubrocerulea seeds bought on the commercial marketdetected an average concentration of LSA of 0.011%. The Ipomoea mix contained a concentration of LSA about 10 times lower than that of seized Morning Glory seeds. Conclusion Seeds bought on the commercial market contained doses of LSA capable of provoking hallucinogenic effects. In the absence of data on the toxicity resulting from the ingestion of seeds for ornamental purposes, we believe that further research on the actual safety of ornamental seeds is necessary
The PPARγ2 P12A polymorphism is not associated with all-cause mortality in patients with type 2 diabetes mellitus
The high mortality risk of patients with type 2 diabetes mellitus may well be explained by the several comorbidities and/or complications. Also the intrinsic genetic component predisposing to diabetes might have a role in shaping the risk of diabetes-related mortality. Among type 2 diabetes mellitus SNPs, rs1801282 is of particular interest because (i) it is harbored by peroxisome proliferator-activated receptor-γ2 (PPARγ2), which is the target for thiazolidinediones which are used as antidiabetic drugs, decreasing all-cause mortality in type 2 diabetes mellitus, and (ii) it is associated with insulin resistance and related traits, risk factors for overall mortality in type 2 diabetes mellitus. We investigated the role of PPARγ2 P12A, according to a dominant model (PA + AA vs. PP individuals) on incident all-cause mortality in three cohorts of type 2 diabetes mellitus, comprising a total of 1672 patients (462 deaths) and then performed a meta-analysis of ours and all available published data. In the three cohorts pooled and analyzed together, no association between PPARγ2 P12A and all-cause mortality was observed (HR 1.02, 95 % CI 0.79–1.33). Similar results were observed after adjusting for age, sex, smoking habits, and BMI (HR 1.09, 95 % CI 0.83–1.43). In a meta-analysis of ours and all studies previously published (n = 3241 individuals; 666 events), no association was observed between PPARγ2 P12A and all-cause mortality (HR 1.07, 95 % CI 0.85–1.33). Results from our individual samples as well as from our meta-analysis suggest that the PPARγ2 P12A does not significantly affect all-cause mortality in patients with type 2 diabetes mellitus
Numerical Simulation of a Hollow-Core Woodpile-Based Mode Launcher for Dielectric Laser Accelerators
Hollow core microstructures powered by infrared lasers represent a new and promising area of accelerator research, where advanced concepts of electromagnetism must be used to satisfy multiple requirements. Here, we present the design of a dielectric electromagnetic band gap (EBG) mode launcher–converter for high-power coupling in dielectric laser accelerators (DLAs). The device is based on a silicon woodpile structure, and it is composed of two perpendicularly coupled hollow-core waveguides—a transverse electric (TE)-like mode waveguide (excited from laser power) and a transverse magnetic (TM)-like mode (accelerating) waveguide—in analogy with the TE10-to-TM01 waveguide mode converters of radio frequency (RF) linear accelerators (LINACs). The structure is numerically designed and optimized, showing insertion losses (IL) <0.5 dB and efficient mode conversion in the operating bandwidth. The operating wavelength is 5 μm, corresponding to a frequency of ≈60 THz, in a spectral region where solid-state continuous-wave (CW) lasers exist and are actively developed. The presented woodpile coupler shows an interaction impedance in the order of 10 kΩ, high power handling and efficiency
Le cave di gesso di Vezzano sul Crostolo (RE): studi geologico-tecnici finalizzati al recupero ambientale dell’area
The PLASMONX Project for advanced beam physics experiments
The Project PLASMONX is well progressing into its
design phase and has entered as well its second phase of
procurements for main components. The project foresees
the installation at LNF of a Ti:Sa laser system (peak
power > 170 TW), synchronized to the high brightness
electron beam produced by the SPARC photo-injector.
The advancement of the procurement of such a laser
system is reported, as well as the construction plans of a
new building at LNF to host a dedicated laboratory for
high intensity photon beam experiments (High Intensity
Laser Laboratory). Several experiments are foreseen
using this complex facility, mainly in the high gradient
plasma acceleration field and in the field of mono-
chromatic ultra-fast X-ray pulse generation via Thomson
back-scattering. Detailed numerical simulations have
been carried out to study the generation of tightly focused
electron bunches to collide with laser pulses in the
Thomson source: results on the emitted spectra of X-rays
are presented
Management of the corpse with suspect, probable or confirmed COVID-19 respiratory infection \u2013 Italian interim recommendations for personnel potentially exposed to material from corpses, including body fluids, in morgue structures and during autopsy practice.
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BriXs ultra high fluxinverse compton source based on modified push-pull energy recovery linacs
We present a conceptual design for a compact X-ray Source BriXS (Bright and compact
X-ray Source). BriXS, the first stage of the Marix project, is an Inverse Compton Source (ICS) of
X-ray based on superconducting cavities technology for the electron beam with energy recirculation
and on a laser system in Fabry-Pérot cavity at a repetition rate of 100 MHz, producing 20–180 keV
monochromatic X-Rays devoted mainly to medical applications. An energy recovery scheme based on
a modified folded push-pull CW-SC twin Energy Recovery Linac (ERL) ensemble allows us to sustain
an MW-class beam power with almost one hundred kW active power dissipation/consumption
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