1,244 research outputs found

    Experimental method for measuring classical concurrence of generic beam shapes

    Full text link
    Classical entanglement is a powerful tool which provides a neat numerical estimate for the study of classical correlations. Its experimental investigation, however, has been limited to special cases. Here, we demonstrate that the experimental quantification of the level of classical entanglement can be carried out in more general instances. Our approach enables the extension to arbitrarily shaped transverse modes and hence delivering a suitable quantification tool to describe concisely the modal structure

    Parameter Estimation with Mixed-State Quantum Computation

    Full text link
    We present a quantum algorithm to estimate parameters at the quantum metrology limit using deterministic quantum computation with one bit. When the interactions occurring in a quantum system are described by a Hamiltonian H=θH0H= \theta H_0, we estimate θ\theta by zooming in on previous estimations and by implementing an adaptive Bayesian procedure. The final result of the algorithm is an updated estimation of θ\theta whose variance has been decreased in proportion to the time of evolution under H. For the problem of estimating several parameters, we implement dynamical-decoupling techniques and use the results of single parameter estimation. The cases of discrete-time evolution and reference-frame alignment are also discussed within the adaptive approach.Comment: 12 pages. Improved introduction and technical details moved to Appendi

    Personality Disorders

    Get PDF
    The present chapter aims at providing an overview of the current state of the art as to the conceptualization, diagnosis, epidemiology, etiological correlates, and treatment of personality disorders (PDs). The two DSM-5 models for PDs (i.e., the traditional categorical model listed in DSM-5 Section II and the Alternative Model of PD proposed in DSM-5 Section III) are reviewed and the scientific rationale for moving from a categorical model to an empirically based dimensional model of PDs are presented. Key aspects and basic principles of PD treatment are summarized. Finally, the chapter offers three clinical vignettes to help the reader familiarizing with the clinical presentation of PDs

    Efficient solvability of Hamiltonians and limits on the power of some quantum computational models

    Full text link
    We consider quantum computational models defined via a Lie-algebraic theory. In these models, specified initial states are acted on by Lie-algebraic quantum gates and the expectation values of Lie algebra elements are measured at the end. We show that these models can be efficiently simulated on a classical computer in time polynomial in the dimension of the algebra, regardless of the dimension of the Hilbert space where the algebra acts. Similar results hold for the computation of the expectation value of operators implemented by a gate-sequence. We introduce a Lie-algebraic notion of generalized mean-field Hamiltonians and show that they are efficiently ("exactly") solvable by means of a Jacobi-like diagonalization method. Our results generalize earlier ones on fermionic linear optics computation and provide insight into the source of the power of the conventional model of quantum computation.Comment: 6 pages; no figure

    Impairment of the autophagic flux in astrocytes intoxicated by trimethyltin

    Get PDF
    Autophagy is a lysosomal catabolic route for protein aggregates and damaged organelles which in different stress conditions, such as starvation, generally improves cell survival. An impairment of this degradation pathway has been reported to occur in many neurodegenerative processes. Trimethyltin (TMT) is a potent neurotoxin present as an environmental contaminant causing tremors, seizures and learning impairment in intoxicated subjects. The present data show that in rat primary astrocytes autophagic vesicles (AVs) appeared after few hours of TMT treatment. The analysis of the autophagic flux in TMT-treated astrocytes was consistent with a block of the late stages of autophagy and was accompanied by a progressive accumulation of the microtubule associated protein light chain 3 (LC3) and of p62/SQSTM1. Interestingly, an increased immunoreactivity for p62/SQSTM1 was also observed in hippocampal astrocytes detected in brain slices of TMT-intoxicated rats. The time-lapse recordings of AVs in EGFP-mCherry-LC3B transfected astrocytes demonstrated a reduced mobility of autophagosomes after TMT exposure respect to control cells. The observed block of the autophagic flux cannot be overcome by known autophagy inducers such as rapamycin or 0.5mM lithium. Although ineffective when used at 0.5mM, lithium at higher concentrations (2mM) was able to protect astrocyte cultures from TMT toxicity. This effect correlated well with its ability to determine the phosphorylation/inactivation of glycogen kinase synthase-3β (GSK-3β)

    Application of imaging guidelines in patients with foreign body ingestion or inhalation: literature review

    Get PDF
    Ingestion, inhalation, and insertion of foreign bodies (FBs) are very common clinical occurrences. In any case, early diagnosis and prompt management are mandatory to avoid severe and life-threatening complications. Radiologists have an important role in revealing the presence, dimension, nature, and relationship with anatomical structures of a FB; selecting the most appropriate imaging modality; and enabling the best therapeutic choice. This review article focuses on the most frequent FBs ingested, inhaled, and inserted and presents the different tests and investigations to provide a correct radiological approach

    Bioactive Compounds from Marine Sponges and Algae: Effects on Cancer Cell Metabolome and Chemical Structures

    Get PDF
    Metabolomics represent the set of small organic molecules generally called metabolites, which are located within cells, tissues or organisms. This new “omic” technology, together with other similar technologies (genomics, transcriptomics and proteomics) is becoming a widely used tool in cancer research, aiming at the understanding of global biology systems in their physiologic or altered conditions. Cancer is among the most alarming human diseases and it causes a considerable number of deaths each year. Cancer research is one of the most important fields in life sciences. In fact, several scientific advances have been made in recent years, aiming to illuminate the metabolism of cancer cells, which is different from that of healthy cells, as suggested by Otto Warburg in the 1950s. Studies on sponges and algae revealed that these organisms are the main sources of the marine bioactive compounds involved in drug discovery for cancer treatment and prevention. In this review, we analyzed these two promising groups of marine organisms to focus on new metabolomics approaches for the study of metabolic changes in cancer cell lines treated with chemical extracts from sponges and algae, and for the classification of the chemical structures of bioactive compounds that may potentially prove useful for specific biotechnological applications

    Coverage of exposed hardware after lower leg fractures with free flaps or pedicled flaps

    Get PDF
    Abstract. – OBJECTIVE: The placement of osteosynthetic materials in the leg may be complicated by hardware exposure. Successful soft tissue reconstruction often provides a critical means for limb salvage in patients with hardware exposure in the leg. Free flaps are currently considered the standard surgical procedure for soft tissue coverage of the wounds with internal hardware exposure. However, to date, no conclusive literature shows the superiority of a specific type of flap. MATERIALS AND METHODS: The current review compares data from the literature concerning outcomes and complications of free and pedicled flaps for exposed osteosynthetic material preservation in the leg. RESULTS: A total of 81 cases from twelve different articles presenting internal hardware exposure of the leg were analyzed in our study. Thirty-two patients underwent immediate reconstructive surgery with pedicled flaps, while forty-nine patients underwent free flap reconstruction. The overall survival rate for pedicled flaps was 96.77%, while for free flaps it was 97.77%. The overall implant preservation rate was 78.12% for pedicled flaps and 53.33% for free flaps. With reference to postoperative complications, the overall complication rate was 46.87% for pedicled flaps and 10.20% for free flaps. CONCLUSIONS: No significant difference was found in terms of overall flap survival. However, a significant difference was found regarding successful implant preservation (78.12% in the pedicled flap group vs. 53.33% in the free flap group). In particular, the first observation appears to be in contrast with the current trend of considering the free flaps the first choice procedure for soft tissue coverage of the wounds with internal hardware exposure. Nevertheless, a higher occurrence of postoperative complications was observed in the pedicled flap group (46.87% vs. 10.20%). The choice of the most appropriate reconstructive procedure should take into account several issues including the size of the wounds with internal hardware exposure, the possibility of soft tissue coverage with pedicled flaps, the availability of recipient vessels, general conditions of the patients (such as age, diabetes, smoking history), patients’ preference and presence of a microsurgical team. However, according to the results of this review, we believe that pedicled flap reconstruction should be reconsidered as a valid alternative procedure for skin tissue loss with hardware exposure whenever it is possible

    Plasma technology increases the efficacy of prothioconazole against fusarium graminearum and fusarium proliferatum contamination of maize (Zea mays) seedlings

    Get PDF
    The contamination of maize by Fusarium species able to produce mycotoxins raises great concern worldwide since they can accumulate these toxic metabolites in field crop products. Further-more, little information exists today on the ability of Fusarium proliferatum and Fusarium graminearum, two well know mycotoxigenic species, to translocate from the seeds to the plants up to the kernels. Marketing seeds coated with fungicide molecules is a common practice; however, since there is a growing need for reducing chemicals in agriculture, new eco-friendly strategies are increasingly tested. Technologies based on ionized gases, known as plasmas, have been used for decades, with newer material surfaces, products, and approaches developed continuously. In this research, we tested a plasma-generated bilayer coating for encapsulating prothioconazole at the surface of maize seeds, to protect them from F. graminearum and F. proliferatum infection. A minimum amount of chemical was used, in direct contact with the seeds, with no dispersion in the soil. The ability of F. graminearum and F. proliferatum species to translocate from seeds to seedlings of maize has been clearly proven in our in vitro experiments. As for the use of plasma technology, the combined use of the plasma-generated coating with embedded prothioconazole was the most efficient approach, with a higher reduction of the infection of the maize seminal root system and stems. The debated capability of the two Fusarium species to translocate from seeds to seedlings has been demonstrated. The plasma-generated coating with embedded prothioconazole resulted in a promising sustainable approach for the protection of maize seedlings

    Characterization of the proteins involved in the DNA repair mechanism in M. smegmatis.

    Get PDF
    : Several alkylating agents that either occur in the environment or are self-produced can cause DNA-damaging injuries in bacterial cells. Therefore, all microorganisms have developed repair systems that are able to counteract DNA alkylation damage. The adaptive response to alkylation stress in Escherichia coli consists of the Ada operon, which has been widely described; however, the homologous system in Mycobacterium tuberculosis (MTB) has been shown to have a different genetic organization but it is still largely unknown. In order to describe the defense system of MTB, we first investigated the proteins involved in the repair mechanism in the homologous non-pathogenic mycobacterium M. smegmatis. Ogt, Ada-AlkA and FadE8 proteins were recombinantly produced, purified and characterized. The biological role of Ogt was examined using proteomic experiments to identify its protein partners in vivo under stress conditions. Our results suggested the formation of a functional complex between Ogt and Ada-AlkA, which was confirmed both in silico by docking calculations and by gel filtration chromatography. We propose that this stable association allows the complex to fulfill the biological roles exerted by Ada in the homologous E. coli system. Finally, FadE8 was demonstrated to be structurally and functionally related to its E. coli homologous, Aid
    • …
    corecore