An Upper Bound for the Number of Rectangulations of a Planar Point Set

We prove that every set of n points in the plane has at most $17^n$ rectangulations. This improves upon a long-standing bound of Ackerman. Our proof is based on the cross-graph charging-scheme technique.Comment: 8 pages, 5 figure

Hair testing of GHB: an everlasting issue in forensic toxicology

In this paper, the authors present a critical review of different studies regarding hair testing of endogenous γ-hydroxybutyrate (GHB), concentrations in chronic users, and values measured after a single GHB exposure in drug facilitated sexual assault (DFSA) cases together with the role of a recently identified GHB metabolite, GHB-glucuronide. Content: The following databases (up to March 2017) PubMed, Scopus and Web of Science were used, searching the following key words: γ-hydroxybutyrate, GHB, GHB glucuronide, hair. The main key words “GHB” and “γ-hydroxybutyrate” were searched singularly and then associated individually to each of the other keywords. Summary: Of the 2304 sources found, only 20 were considered appropriate for the purpose of this paper. Summing up all the studies investigating endogenous GHB concentration in hair, a very broad concentration range from 0 to 12 ng/mg was found. In order to detect a single GHB dose in hair it is necessary to commonly wait 1 month for collecting hair and a segmental analysis of 3 or 5 mm fragments and the calculation of a ratio between the targeted segment and the others represent a reliable method to detect a single GHB intake considering that the ratios presently proposed vary from 3 and 10. The only two studies so far performed, investigating GHB-Glucuronide in hair, show that the latter does not seem to provide any diagnostic information regarding GHB exposure

Unreliable estimation of prevalence of fetal alcohol syndrome

Svetlana Popova and colleagues (March, 2017)1 sought to estimate the global, regional, and national prevalence of alcohol use during pregnancy and fetal alcohol syndrome (FAS). The authors reviewed inter-national literature from 1984 for country-specific quantitative studies and for countries with one or no studies they predicted gestational alcohol use prevalence by fractional response regression modelling and prevalence of FAS by an estimated quotient for the average number of women consuming alcohol during pregnancy per one case of FAS. For estimation of FAS prevalence, Italy was reported to be among the five countries worldwide with the highest prevalence of FAS per 10000 peopl

Herbal highs: review on psychoactive effects and neuropharmacology

Background: A new trend among users of new psychoactive substances’ the consumption of “herbal highs”: plant parts containing psychoactive substances. Most of the substances extracted from herbs, in old centuries were at the centre of religious ceremonies of ancient civilizations. Currently, these herbal products are mainly sold by internet web sites and easily obtained since some of them have no legal restriction. Objective: We reviewed psychoactive effects and neuropharmacology of the most used “herbal highs” with characterized active principles, with studies reporting mechanisms of action, pharmacological and subjective effects, eventual secondary effects including intoxications and/or fatalities Method: The PubMed database was searched using the following key.words: herbal highs, Argyreia nervosa, Ipomoea violacea and Rivea corymbosa; Catha edulis; Datura stramonium; Piper methysticum; Mitragyna speciosa. Results: Psychoactive plants here reviewed have been known and used from ancient times, even if for some of them limited information still exist regarding subjective and neuropharmacological effects and consequent eventual toxicity when plants are used alone or in combination with “classical” drugs of abuse. Conclusion: Some “herbal highs” should be classified as harmful drugs since chronic administration has been linked with addiction and cognitive impairment; for some others taking into consideration only the recent trends of abuse, studies investigating these aspects are lacking

Classical Limit of Higher-Spin String Amplitudes

It has been shown that a special set of three-point amplitudes between two massive spinning states and a graviton reproduces the linearised stress-energy tensor for a Kerr black hole in the classical limit. In this work we revisit this result and compare it to the analysis of the amplitudes describing the interaction of leading Regge states of the open and closed superstring. We find an all-spin result for the classical limit of two massive spinning states interacting with a photon or graviton. This result differs from Kerr and instead matches the current four-vector and the stress-energy tensor generated by a classical string coupled to electromagnetism and gravity respectively. For the superstring amplitudes, contrary to the black-hole case, we find that the spin to infinity limit is necessary to reproduce the classical spin multipoles.Comment: 23 pages plus ref

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