Quantum annealing and the Schr\"odinger-Langevin-Kostin equation

We show, in the context of quantum combinatorial optimization, or quantum annealing, how the nonlinear Schr\"odinger-Langevin-Kostin equation can dynamically drive the system toward its ground state. We illustrate, moreover, how a frictional force of Kostin type can prevent the appearance of genuinely quantum problems such as Bloch oscillations and Anderson localization which would hinder an exhaustive search.Comment: 5 pages, 4 figures. To appear on Physical Review

Wild and cultivated plants used in traditional alcoholic beverages in Italy: an ethnobotanical review

This study aims to gather, analyze, and discuss the ethnobotanical information regarding wild and cultivated plants used in traditional alcoholic beverages in Italy. The online literature search allowed data collection from 161 articles concerning the use of wild and cultivated plants in Italy for liqueurs preparation. Overall, we identified 130 taxa belonging to 35 families, among them Rosaceae is the most cited (21.4%) followed by Asteraceae (14.3%), Lamiaceae (12.7%), Apiaceae and Pinaceae (5.6% each). Tuscany (N=49), Friuli Venezia Giulia (N=46) and Lombardy (N=36) show the largest number of species used in a single region. The common use of liqueurs as aperitif and digestive is also discussed. This work increases the ethnobotanical data of traditional alcoholic beverages from Italy, till now not well explored. This study can be the basis for future research on the supposed bioactivity and toxicity of alcoholic beverages

A Strategy for Efficiently Collecting Aerosol Condensate Using Silica Fibers: Application to Carbonyl Emissions from E-Cigarettes

Analyzing harmful constituents in e-cigarette aerosols typically involves adopting a methodology used for analyzing tobacco smoke. Cambridge filter pads (CFP) are the basis of numerous protocols for analyzing the various classes of compounds representing 93 harmful and potentially harmful constituents identified in tobacco smoke by the FDA. This paper describes a simplified method for trapping the low volatility components of e-cigarette aerosols using a single trapping procedure followed by physical extraction. The trap is a plug of amorphous silica fibers (0.75 g of 4 μm diameter) within a 10 mL syringe inserted between the e-cigarette mouthpiece and the pump of the vaping machine. The method is evaluated for emissions from three generations of e-cigarette device (Kangertech CE4, EVOD, and Subox Mini-C). On average, the silica wool traps about 94% of the vaporized liquid mass in the three devices and higher levels of condensate is retained before reaching saturation compared with CFP. The condensate is then physically extracted from the silica wool plug using a centrifuge. Condensate is then available for use directly in multiple analytical procedures or toxicological experiments. The method is tested by comparison with published analyses of carbonyls, among the most potent toxicants and carcinogens in e-cigarette emissions. Ranges for HPLC-DAD analyses of carbonyl-DNPH derivatives in a laboratory formulation of e-liquid are formaldehyde (0.182 ± 0.023 to 9.896 ± 0.709 μg puff-1), acetaldehyde (0.059 ± 0.005 to 0.791 ± 0.073 μg puff-1), and propionaldehyde (0.008 ± 0.0001 to 0.033 ± 0.023 μg puff-1); other carbonyls are identified and quantified. Carbonyl concentrations are also consistent with published experiments showing marked increases with variable power settings (10W to 50W). Compared with CFPs, e-cigarette aerosol collection by silica wool requires only one vaping session for multiple analyte groups, traps more condensate per puff, and collects more condensate before saturation

Speed and entropy of an interacting continuous time quantum walk

We present some dynamic and entropic considerations about the evolution of a continuous time quantum walk implementing the clock of an autonomous machine. On a simple model, we study in quite explicit terms the Lindblad evolution of the clocked subsystem, relating the evolution of its entropy to the spreading of the wave packet of the clock. We explore possible ways of reducing the generation of entropy in the clocked subsystem, as it amounts to a deficit in the probability of finding the target state of the computation. We are thus lead to examine the benefits of abandoning some classical prejudice about how a clocking mechanism should operate.Comment: 25 pages, 14 figure

Grover's algorithm on a Feynman computer

We present an implementation of Grover's algorithm in the framework of Feynman's cursor model of a quantum computer. The cursor degrees of freedom act as a quantum clocking mechanism, and allow Grover's algorithm to be performed using a single, time-independent Hamiltonian. We examine issues of locality and resource usage in implementing such a Hamiltonian. In the familiar language of Heisenberg spin-spin coupling, the clocking mechanism appears as an excitation of a basically linear chain of spins, with occasional controlled jumps that allow for motion on a planar graph: in this sense our model implements the idea of "timing" a quantum algorithm using a continuous-time random walk. In this context we examine some consequences of the entanglement between the states of the input/output register and the states of the quantum clock

One size doesn’t fit all: the influence of supervisors’ power tactics and subordinates’ need for cognitive closure on burnout and stress

The present research investigated the notion of fit between supervisors’ power tactics and subordinates’ need for cognitive closure (NFCC) on subordinates’ burnout and stress. Subordinates who tend to avoid ambiguity (high NFCC) were expected to experience relatively less burnout (Study 1) and stress (Study 2) if their supervisors utilize harsh (controlling and unequivocal) power tactics and more burnout and stress if their supervisors utilize soft (autonomy-supportive and equivocal) power tactics. In contrast, it was expected that subordinates who avoid firm and binding conclusions (low NFCC) would experience relatively less burnout and stress if their supervisors use soft power tactics and more burnout and stress if they use harsh power tactics. Two studies conducted in diverse organizational settings supported these hypotheses. Collectively, these results support the conclusion that soft (vs. harsh) power tactics are not always associated with better (vs. worse) organizational outcomes. Theoretical and practical implications for organizations are discussed

Assessment of cytotoxicity in ten strains of Gambierdiscus australes from Macaronesian Islands by neuro-2a cell-based assays

Within the dinoflagellate genus Gambierdiscus several species are well-known producers of ciguatoxins (CTXs) and maitotoxins (MTXs). These compounds are potent marine toxins that accumulate through the food chain, leading to a foodborne disease known as ciguatera when contaminated fish is consumed. Given the threat that the presence of these toxins in seafood may pose to human health and fisheries, there is an evident necessity to assess the potential toxicity of Gambierdiscus sp. in a particular area. Thus, the purpose of this work was to evaluate the production of CTX and MTX of 10 strains of Gambierdiscus australes isolated from the Selvagem Grande Island (Madeira, Portugal) and El Hierro Island (Canary Islands, Spain). The strains were first characterized by light microscopy and species were confirmed by molecular biology, being identified as G. australes. Following the species identification, CTX and MTX production of G. australes extracts was evaluated at the exponential growth phase using neuro-2a cell-based assays. Additionally, the production of MTX was also investigated in two of the G. australes strains collected at the stationary growth phase. Interestingly, 9 out of 10 strains were found to produce CTX-like compounds, ranging from 200 to 697 fg equiv. CTX1B cell−1. None of the G. australes strains showed MTX-like activity at the exponential phase, but MTX production was observed in two strains at the stationary growth phase (227 and 275 pg equiv. MTX cell−1). Therefore, the presence of G. australes strains potentially producing CTX and MTX in these Macaronesian Islands was confirmed.info:eu-repo/semantics/acceptedVersio

Anderson localization in Bose-Einstein condensates

The understanding of disordered quantum systems is still far from being complete, despite many decades of research on a variety of physical systems. In this review we discuss how Bose-Einstein condensates of ultracold atoms in disordered potentials have opened a new window for studying fundamental phenomena related to disorder. In particular, we point our attention to recent experimental studies on Anderson localization and on the interplay of disorder and weak interactions. These realize a very promising starting point for a deeper understanding of the complex behaviour of interacting, disordered systems.Comment: 15 pages review, to appear in Reports on Progress in Physic

The role of Matriptase-2 during the early postnatal development in humans

Hepcidin is the hepatic peptide hormone, which regulates the systemic iron homeostasis by degrading the only cellular iron exporter ferroportin. The transmembrane serine protease matriptase-2 (MT-2, encoded by TMPRSS6) is a major hepcidin inhibitor and mutations in TMPRSS6 gene are responsible of inherited iron refractory iron deficiency anemia (IRIDA), characterized by hypochromic microcytic anemia, low transferrin saturation and inappropriate normal/high levels of hepcidin. In this study we retrospectively analyzed the hematological parameters in the (neo) perinatal period of IRIDA patients to understand the role of matriptase-2 at birth and during early development. We found that anemia is not present at birth and thus we inferred that it is absent also in utero but develops after the second month of life. Our results might have implications to better understand iron homeostasis during early development in IRIDA patients and indicate that Mt2 is dispensable during fetal and neonatal life in humans, consistent with the idea that the downregulation of hepcidin by Mt2 becomes effective only with the introduction of dietary iron

Microlensing induced spectral variability in Q2237+0305

We present both photometry and spectra of the individual images of the quadruple gravitational lens system Q2237+0305. Comparison of spectra obtained at two epochs, separated by $\sim~3\,$years, shows evidence for significant changes in the emission line to continuum ratio of the strong ultraviolet CIV~$\lambda$1549, CIII]~$\lambda$1909 and MgII~$\lambda$2798 lines. The short, $\sim~1\,$day, light--travel time differences between the sight lines to the four individual quasar images rule out any explanation based on intrinsic variability of the source. The spectroscopic differences thus represent direct detection of microlensing--induced spectroscopic differences in a quasar. The observations allow constraints to be placed on the relative spatial scales in the nucleus of the quasar, with the ultra--violet continuum arising in a region of \la~0.05~{\rm pc} in extent, while the broad emission line material is distributed on scales much greater than this.Comment: Accepted for Publication in MNRAS. Paper with 11 figure