1,009 research outputs found
Synthetic cathinones related fatalities: an update
Synthetic cathinones, more commonly known as "bath salts", are synthetic drugs chemically related to cathinone, a psychostimulant found in the khat plant. They are the first most consumed products among new psychoactive substances, which cause psychostimulant and hallucinogenic effects determining a number of fatalities worldwide. In this paper, we have systematically reviewed cases of synthetic cathinones-related fatalities analytically confirmed, which have occurred in the last few years.OBJECTIVE: Synthetic cathinones,
more commonly known as “bath salts”, are synthetic
drugs chemically related to cathinone, a
psychostimulant found in the khat plant. They are
the first most consumed products among new
psychoactive substances, which cause psychostimulant
and hallucinogenic effects determining
a number of fatalities worldwide. In this paper, we
have systematically reviewed cases of synthetic
cathinones-related fatalities analytically confirmed,
which have occurred in the last few years.
MATERIALS AND METHODS: Relevant scientific
articles were identified in Medline, Cochrane
Central, Scopus, Web of Science and Institutional/
government websites up to November 2017
using the following keywords: synthetic cathinones,
mephedrone, methylenedioxypyrovalerone,
MDPV, methylone, ethylone, buthylone, fatal
intoxication, fatalities and death.
RESULTS: In total, 20 citations met the criteria
for inclusion, representing several fatal cases
with analytically confirmed synthetic cathinones
in biological sample/s of the deceased. The
death was attributed to hyperthermia, hypertension,
cardiac arrest and more in general to the
classic serotonin syndrome. Only rarely did the
concentration of the parent drug causing fatality
overcome the value of 1 mg/L in post-mortem
biological fluids.
CONCLUSIONS: Abuse of synthetic cathinones
still represents a serious public health issue.
Systematic clinical studies on both the animal
and human model are lacking; therefore, the
only available data are from the users who experience
the possible hazardous consequences.
Analytical methodologies for the identification
of parent compounds and eventual metabolites
both in ante-mortem and post-mortem cases
need to be developed and validated. Analytical
data should be shared through different communication
platforms with the aim of stopping this
serious health threat for drug users
Structure and Dynamics of amorphous Silica Surfaces
We use molecular dynamics computer simulations to study the equilibrium
properties of the surface of amorphous silica. Two types of geometries are
investigated: i) clusters with different diameters (13.5\AA, 19\AA, and
26.5\AA) and ii) a thin film with thickness 29\AA. We find that the shape of
the clusters is independent of temperature and that it becomes more spherical
with increasing size. The surface energy is in qualitative agreement with the
experimental value for the surface tension. The density distribution function
shows a small peak just below the surface, the origin of which is traced back
to a local chemical ordering at the surface. Close to the surface the partial
radial distribution functions as well as the distributions of the bond-bond
angles show features which are not observed in the interior of the systems. By
calculating the distribution of the length of the Si-O rings we can show that
these additional features are related to the presence of two-membered rings at
the surface. The surface density of these structures is around 0.6/nm^2 in good
agreement with experimental estimates. From the behavior of the mean-squared
displacement at low temperatures we conclude that at the surface the cage of
the particles is larger than the one in the bulk. Close to the surface the
diffusion constant is somewhat larger than the one in the bulk and with
decreasing temperature the relative difference grows. The total vibrational
density of states at the surface is similar to the one in the bulk. However, if
only the one for the silicon atoms is considered, significant differences are
found.Comment: 30 pages of Latex, 16 figure
A numerical study of squeeze-film damping in MEMS-based structures including rarefaction effects
In a variety of MEMS applications, the thin film of fluid responsible of squeeze-film dampingresults to be rarefied and, thus, not suitable to be modeled though the classical Navier-Stokes equation. Thesimplest way to consider fluid rarefaction is the introduction of a slight modification into its ordinaryformulation, by substituting the standard fluid viscosity with an effective viscosity term. In the present paper,some squeeze-film damping problems of both parallel and torsion plates at decreasing pressure are studied bynumerical solving a full 3D Navier-Stokes equation, where the effective viscosity is computed according toproper expressions already included in the literature. Furthermore, the same expressions for the effectiveviscosity are implemented within known analytical models, still derived from the Navier-Stokes equation. In allthe considered cases, the numerical results are shown to be very promising, providing comparable or evenbetter agreement with the experimental data than the corresponding analytical results, even at low air pressure.Thus, unlike what is usually agreed in the literature, the effective viscosity approach can be efficiently applied atlow pressure regimes, especially when this is combined with a finite element analysis (FE
Hepatotoxicity induced by greater celandine (Chelidonium majus L.): a review of the literature
The available literature assessing Chelidonium majus L. (CM) hepatotoxicity potential, and its risk to benefit assessment has been reviewed in this paper. Identification of significant scientific literature was performed via the following research databases: Cochrane Central, Google Scholar, EMBASE, Medline, Science Direct, Scopus, Web of Science, using the following keywords: "Chelidonium majus", "greater celandine", "Hepatotoxicity", "Liver" "Injury", "Toxicity" individually investigated and then again in association. CM named also greater celandine, swallow-wort, or bai-qu-cai (Chinese), has been used for a long time in traditional Chinese medicine and phytotherapy. Its extracts have been claimed to display a wide variety of biological activities: antimicrobial, anti-inflammatory, spasmolytic, antineoplastic, hepatoprotective, and analgesic. Moreover, herbal medicine suggests this plant have numerous additional effects which have not yet been scientifically evaluated, such as antitussive, diuretic, and eye-regenerative. However, despite its claimed hepatoprotective effects, several hepatotoxicity cases have been reported to be probably or highly probably connected with CM exposure, after their evaluation through liver-targeted causality assessment methods. CM hepatotoxicity has been defined as a distinct form of herb-induced liver injury (HILI), due to an idiosyncratic reaction of the metabolic type. This evidence has to be considered in relationship with the absence of considerable benefits of CM therapy. Therefore, the risk to benefit ratio of the use of herbal products containing greater celandine can actually be considered as negative
Analysis of the Parameters Affecting the Stiffness of Short Sisal Fiber Biocomposites Manufactured by Compression-Molding
The use of natural fiber-based composites is on the rise in many industries. Thanks to their eco-sustainability, these innovative materials make it possible to adapt the production of components, systems and machines to the increasingly stringent regulations on environmental protection, while at the same time reducing production costs, weight and operating costs. Optimizing the mechanical properties of biocomposites is an important goal of applied research. In this work, using a new numerical approach, the effects of the volume fraction, average length, distribution of orientation and curvature of fibers on the Young’s modulus of a biocomposite reinforced with short natural fibers were studied. Although the proposed approach could be applied to any biocomposite, sisal fibers and an eco-sustainable thermosetting matrix (green epoxy) were considered in both simulations and the associated experimental assessment. The results of the simulations showed the following effects of the aforementioned parameters on Young’s modulus: a linear growth with the volume fraction, nonlinear growth as the length of the fibers increased, a reduction as the average curvature increased and an increase in stiffness in the x-y plane as the distribution of fiber orientation in the z direction decreased
Testing the Dispersion of Nanoparticles in a Nanocomposite with an Ultra-Low Fill Content Using a Novel Non-Destructive Evaluation Technique
A non-destructive evaluation (NDE) technique capable of testing the dispersion of nanoparticles in a nanocomposite would be of great use to the industry to check the quality of the products made and to ensure compliance with their specifications. Very few NDE techniques found in the literature can evaluate the level of dispersion of the nanoparticles in the whole nanocomposite. Here, a recently developed NDE technique based on pulsed phase thermography (PPT) in transmission mode was used to assess the particle dispersion in ultra-low, less than 0.05 wt%, Ag enriched polymeric based nanocomposite manufactured with an innovative nano-coating fragmentation technique. The phasegrams obtained with the presented technique clearly showed clusters or bundles of Ag nanoparticles when present, down to the size of 6 µm. Therefore, the new NDE approach can be applied to verify that the expected levels of dispersion are met in the production process
A Case of Gout from Imperial Rome (1st-2nd Century AD)
The study of pathological alterations in ancient skeletal remains may contribute to the reconstruction of the history
of diseases and health conditions of ancient populations. Therefore, in recent research palaeopathology provides an
important point of view in bioarchaeology and medicine.
This work describes the bone alterations observed in the skeleton of an adult woman found during archaeological
excavations in the greatest necropolis of the Imperial Age in Rome. The skeletal remains showed some pathological anomalies and the most evident alterations consisted of multiple osteolytic lesions involving mainly the small bones of the feet, which presented round cavitations and scarce signs of bone repair. Differential diagnosis suggests that this individual was affected by gout, probably associated with hypothyroidism that determined her short stature
Short-Facelift Approach in Temporal Artery Biopsy: Is It Safe?
Giant cell arteritis (GCA) is a quite common panarteritis of the elderly that affects medium- and large-size arteries. Despite the increasing role of imaging with advancing technology, the gold standard for the diagnosis of GCA is still the temporal artery biopsy. A described complication of superficial temporal artery biopsy (STAB), for which incidence is not clear, is the accidental damage of the frontal branch of the facial nerve. In this paper, we described the short-scar facelift surgical approach for STAB on 23 consecutive patients who underwent unilateral superficial temporal artery biopsy for GCA suspicion. We collected data in terms of postoperative complications, biopsy specimen length, biopsy result and cosmetic appearance of the scar. In our experience, this surgical approach combines the advantage of avoiding incisions within the dangerous anatomical area, minimizing the risk of facial nerve damage, with an acceptable complication rate and a good final aesthetic result which avoids visible scarring
The daily life of a researcher introduced with an online data analysis experience based on visual programming
A common criticism for the Italian higher education system is the gap that separates it from the employment landscape. To improve this situation, our department and schools are sponsoring internships, to expose the students to the work life. Groups of two high school students are invited to work with researchers for a week. A tutor introduces them to the research theme and proposes related activities. In order not to require previous experience with programming languages, the visual programming language Blockly is used as the development toolkit, for its suitability for educational activities. We present the development of new functionalities for Blockly purposely for the project: online reading data from a real detection system, interactive analysis, and online data visualization. The activity was successfully experienced by the students hosted in the research group. The actual implementation of the analysis algorithm was quickly achieved, even with no prior experience with data analysis. We bypassed the difficulties related to the syntax of programming languages, by employing Blockly and our added features; this allowed us to focus on the fundamental concepts. The students enjoyed the whole experience and were very proactive asking relevant questions and proposing ideas
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