BALANCE EQUATIONS-BASED PROPERTIES OF THE RABI HAMILTONIAN

A stationary physical system satisfies peculiar balance conditions involving mean values of appropriate observables. In this paper, we show how to deduce such quantitative links, named balance equations, demonstrating as well their usefulness in bringing to light physical properties of the system without solving the Schr¨odinger equation. The knowledge of such properties in the case of the Rabi Hamiltonian is exploited to provide arguments to make easier the variational engineering of the ground state of this model

Effects of pilates exercise programs in people with chronic low back pain: a systematic review

The Pilates method has recently become a fast-growing popular way of exercise recommended for healthy individuals and those engaged in rehabilitation. Several published studies have examined the effects of Pilates method in people with chronic low back pain (LBP).The objective of this study is to describe and provide an extensive overview of the scientific literature comparing the effectiveness of the Pilates method on pain and disability in patients with chronic nonspecific LBP. The study is based on the data from the following sources: MEDLINE-NLM, MEDLINE-EBSCO, Scopus Elsevier, Cochrane, DOAJ, SciELO, and PLOSONE.Original articles and systematic reviews of adults with chronic nonspecific LBP that evaluated pain and/or disability were included in this study; studies in which the primary treatment was based on Pilates method exercises compared with no treatment, minimal intervention, other types of intervention, or other types of exercises.The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) were adopted. The literature search included 7 electronic databases and the reference list of relevant systematic reviews and original articles to July 2014. Two independent investigators conducted the literature search and performed the synthesis as follows: Study Design; Sample (n); Disability measure; Intervention; and Main results.The searches identified a total of 128 articles. From these, 29 were considered eligible and were included in the analysis. The items were stratified as follows: Pilates method versus other kind of exercises (n = 6 trials) and Pilates method versus no treatment group or minimal intervention for short-term pain (n = 9 trials); the therapeutic effect of the Pilates method in randomized cohorts (n = 5); and analysis of reviews (n = 9).We found that there is a dearth of studies that clearly demonstrates the efficacy of a specific Pilates exercise program over another in the treatment of chronic pain. However, the consensus in the field suggests that Pilates method is more effective than minimal physical exercise intervention in reducing pain. These conclusions need to be supported by other proper investigations

Adenoviral-mediated gene transfer of ICP47 inhibits major histocompatibility complex class I expression on vascular cells in vitro

AbstractPurpose: Many viruses have evolved mechanisms to evade detection by the host immune system. The herpes simplex gene ICP47 encodes a protein that binds to the host antigen-processing transporter, inhibiting the formation of major histocompatibility complex class I (MHC-I) antigens in infected cells. MHC-I antigen expression is also important in acute allograft rejection. This study was designed to quantitate the effect of adenoviral-mediated gene transfer of ICP47 on MHC-I cell surface expression of human vascular cells. We hypothesized that the transduction of vascular cells with a replication-incompetent adenoviral vector that was expressing ICP47 (AdICP47) would inhibit constitutive and inducible MHC-I expression and thereby reduce the rate of cytolysis of ICP47-transduced vascular cells by sensitized cytotoxic T lymphocytes (CTL). Methods: A replication-incompetent adenoviral vector, AdICP47, was created to express ICP47 driven by the cytomegalovirus immediate early promoter. Cultured human vascular endothelial and smooth muscle cells and human dermal fibroblasts were transduced with either AdICP47 or the control empty vector AddlE1. Cell surface constitutive and γ-interferon–induced MHC-I expression were quantitated by flow cytometry. A standard 4-hour chromium release cytotoxicity assay was used to determine the percent cytolysis of transduced and nontransduced endothelial cells by sensitized CTL. Finally, to quantitate the specificity of the effect of ICP47 on MHC-I expression, adhesion molecule expression was quantitated in both transduced and nontransduced cells. Results: Constitutive MHC-I expression in AdICP47-transduced endothelial cells was inhibited by a mean of 84% ± 5% (SEM) in five experiments. After 48 hours of exposure to γ-interferon, AdICP47-transduced cells exhibited a mean of 66% ± 8% lower MHC-I expression than nontransduced cells. Similar inhibition in MHC-I expression was achieved in AdICP47-transduced vascular smooth muscle cells and dermal fibroblasts. Percent cytolysis of AdICP47-transduced endothelial cells by CTL was reduced by 72%. Finally, the specificity of the effect of transduction of ICP47 on vascular cell MHC-I expression was confirmed by a lack of significant change in either constitutive or tumor necrosis factor–induced vascular cell adhesion molecule/intercellular adhesion molecule expression. Conclusion: Transduction of vascular cells with AdICP47 strongly inhibits both constitutive and inducible MHC-I expression in human vascular cells. AdICP47-transduced cells exhibited a substantial reduction in cytolysis by CTL. Thus AdICP47 transduction holds promise as a technique to characterize the role of MHC-I expression in acute vascular allograft rejection in vivo and as a potential therapeutic intervention. (J Vasc Surg 2000;31:558-66.

VDAC3 as a sensor of oxidative state of the intermembrane space of mitochondria: the putative role of cysteine residue modifications

Voltage-Dependent Anion selective Channels (VDAC) are pore-forming mitochondrial outer membrane proteins. In mammals VDAC3, the least characterized isoform, presents a set of cysteines predicted to be exposed toward the intermembrane space. We find that cysteines in VDAC3 can stay in different oxidation states. This was preliminary observed when, in our experimental conditions, completely lacking any reducing agent, VDAC3 presented a pattern of slightly different electrophoretic mobilities. This observation holds true both for rat liver mitochondrial VDAC3 and for recombinant and refolded human VDAC3. Mass spectroscopy revealed that cysteines 2 and 8 can form a disulfide bridge in native VDAC3. Single or combined site-directed mutagenesis of cysteines 2, 8 and 122 showed that the protein mobility in SDS-PAGE is influenced by the presence of cysteine and by the redox status. In addition, cysteines 2, 8 and 122 are involved in the stability control of the pore as shown by electrophysiology, complementation assays and chemico-physical characterization. Furthermore, a positive correlation between the pore conductance of the mutants and their ability to complement the growth of porin-less yeast mutant cells was found. Our work provides evidence for a complex oxidation pattern of a mitochondrial protein not directly involved in electron transport. The most likely biological meaning of this behavior is to buffer the ROS load and keep track of the redox level in the intermembrane space, eventually signaling it through conformational change

From a Conceptual Model to a Knowledge Graph for Genomic Datasets

Data access at genomic repositories is problematic, as data is described by heterogeneous and hardly comparable metadata. We previously introduced a unified conceptual schema, collected metadata in a single repository and provided classical search methods upon them. We here propose a new paradigm to support semantic search of integrated genomic metadata, based on the Genomic Knowledge Graph, a semantic graph of genomic terms and concepts, which combines the original information provided by each source with curated terminological content from specialized ontologies. Commercial knowledge-assisted search is designed for transparently supporting keyword-based search without explaining inferences; in biology, inference understanding is instead critical. For this reason, we propose a graph-based visual search for data exploration; some expert users can navigate the semantic graph along the conceptual schema, enriched with simple forms of homonyms and term hierarchies, thus understanding the semantic reasoning behind query results

Anomalous Effects of "Guest" Charges Immersed in Electrolyte: Exact 2D Results

We study physical situations when one or two "guest" arbitrarily-charged particles are immersed in the bulk of a classical electrolyte modelled by a Coulomb gas of positive/negative unit point-like charges, the whole system being in thermal equilibrium. The models are treated as two-dimensional with logarithmic pairwise interactions among charged constituents; the (dimensionless) inverse temperature $\beta$ is considered to be smaller than 2 in order to ensure the stability of the electrolyte against the collapse of positive-negative pairs of charges. Based on recent progress in the integrable (1+1)-dimensional sine-Gordon theory, exact formulas are derived for the chemical potential of one guest charge and for the asymptotic large-distance behavior of the effective interaction between two guest charges. The exact results imply, under certain circumstances, anomalous effects such as an effective attraction (repulsion) between like-charged (oppositely-charged) guest particles and the charge inversion in the electrolyte vicinity of a highly-charged guest particle. The adequacy of the concept of renormalized charge is confirmed in the whole stability region of inverse temperatures and the related saturation phenomenon is revised.Comment: 21 pages, 1 figur

Counterion Condensation and Fluctuation-Induced Attraction

We consider an overall neutral system consisting of two similarly charged plates and their oppositely charged counterions and analyze the electrostatic interaction between the two surfaces beyond the mean-field Poisson-Boltzmann approximation. Our physical picture is based on the fluctuation-driven counterion condensation model, in which a fraction of the counterions is allowed to ``condense'' onto the charged plates. In addition, an expression for the pressure is derived, which includes fluctuation contributions of the whole system. We find that for sufficiently high surface charges, the distance at which the attraction, arising from charge fluctuations, starts to dominate can be large compared to the Gouy-Chapmann length. We also demonstrate that depending on the valency, the system may exhibit a novel first-order binding transition at short distances.Comment: 15 pages, 8 figures, to appear in PR

Proton Decay in a Minimal SUSY SO(10) Model for Neutrino Mixings

A minimal renormalizable SUSY SO(10) model with B-L symmetry broken by {\bf 126} Higgs field has recently been shown to predict all neutrino mixings and the ratio $\Delta m^2_{\odot}/\Delta m^2_A$ in agreement with observations. Unlike models where B-L is broken by {\bf 16} Higgs, this model guarantees automatic R-parity conservation and hence a stable dark matter as well as the absence of dim=4 baryon violating operator without any additional symmetry assumptions. In this paper, we discuss the predictions of the model for proton decay induced at the GUT scale. We scan over the parameter space of the model allowed by neutrino data and find upper bounds on the partial lifetime for the modes $\tau(n\to \pi^0\bar{\nu})=~2\tau(p\to \pi^+\bar{\nu})\leq (5.7-13)\times 10^{32}$ yrs and $\tau(n\to K^0\bar{\nu})\leq 2.97\times 10^{33}$ yrs for the average squark mass of a TeV and wino mass of 200 GeV, when the parameters satisfy the present lower limits on $\tau(p\to K^+\bar{\nu})$ mode. These results can be used to test the model.Comment: 17 pages, 6 figures; Minor corrections with improved predictions; references update

Interactive video retrieval in the age of effective joint embedding deep models: lessons from the 11th VBS

This paper presents findings of the eleventh Video Browser Showdown competition, where sixteen teams competed in known-item and ad-hoc search tasks. Many of the teams utilized state-of-the-art video retrieval approaches that demonstrated high effectiveness in challenging search scenarios. In this paper, a broad survey of all utilized approaches is presented in connection with an analysis of the performance of participating teams. Specifically, both high-level performance indicators are presented with overall statistics as well as in-depth analysis of the performance of selected tools implementing result set logging. The analysis reveals evidence that the CLIP model represents a versatile tool for cross-modal video retrieval when combined with interactive search capabilities. Furthermore, the analysis investigates the effect of different users and text query properties on the performance in search tasks. Last but not least, lessons learned from search task preparation are presented, and a new direction for ad-hoc search based tasks at Video Browser Showdown is introduced

Optical trapping and optical force positioning of two-dimensional materials

In recent years, considerable effort has been devoted to the synthesis and characterization of two-dimensional materials. Liquid phase exfoliation (LPE) represents a simple, large-scale method to exfoliate layered materials down to mono- and few-layer flakes. In this context, the contactless trapping, characterization, and manipulation of individual nanosheets hold perspectives for increased accuracy in flake metrology and the assembly of novel functional materials. Here, we use optical forces for high-resolution structural characterization and precise mechanical positioning of nanosheets of hexagonal boron nitride, molybdenum disulfide, and tungsten disulfide obtained by LPE. Weakly optically absorbing nanosheets of boron nitride are trapped in optical tweezers. The analysis of the thermal fluctuations allows a direct measurement of optical forces and the mean flake size in a liquid environment. Measured optical trapping constants are compared with T-matrix light scattering calculations to show a quadratic size scaling for small size, as expected for a bidimensional system. In contrast, strongly absorbing nanosheets of molybdenum disulfide and tungsten disulfide are not stably trapped due to the dominance of radiation pressure over the optical trapping force. Thus, optical forces are used to pattern a substrate by selectively depositing nanosheets in short times (minutes) and without any preparation of the surface. This study will be useful for improving ink-jet printing and for a better engineering of optoelectronic devices based on two-dimensional materials