2,330 research outputs found

    Existential Types for Relaxed Noninterference

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    Information-flow security type systems ensure confidentiality by enforcing noninterference: a program cannot leak private data to public channels. However, in practice, programs need to selectively declassify information about private data. Several approaches have provided a notion of relaxed noninterference supporting selective and expressive declassification while retaining a formal security property. The labels-as-functions approach provides relaxed noninterference by means of declassification policies expressed as functions. The labels-as-types approach expresses declassification policies using type abstraction and faceted types, a pair of types representing the secret and public facets of values. The original proposal of labels-as-types is formulated in an object-oriented setting where type abstraction is realized by subtyping. The object-oriented approach however suffers from limitations due to its receiver-centric paradigm. In this work, we consider an alternative approach to labels-as-types, applicable in non-object-oriented languages, which allows us to express advanced declassification policies, such as extrinsic policies, based on a different form of type abstraction: existential types. An existential type exposes abstract types and operations on these; we leverage this abstraction mechanism to express secrets that can be declassified using the provided operations. We formalize the approach in a core functional calculus with existential types, define existential relaxed noninterference, and prove that well-typed programs satisfy this form of type-based relaxed noninterference

    The validity of the menopause specific quality of life questionnaire in women with type 2 diabetes

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    OBJECTIVES: To examine the validity and reliability of the Menopause-specific Quality of Life (MENQOL) questionnaire in a sample of women with diabetes in Malaysia, with the secondary aim of determining whether MENQOL domain scores were associated with depression and diabetes. METHODS: A total of 337 postmenopausal women (241 with diabetes, 96 controls) were evaluated. Construct validity was evaluated using principal components analysis (PCA) and comparing scale items against the mental component score of the Short Form-12 (SF-12 MCS), and against the Center for Epidemiologic Studies Depression Scale 10 (CES-D 10). Consistency assessment was conducted using Cronbach's α. RESULTS: The internal consistencies for the physical (PHS), psychosocial (PS), sexual (VSS) and vasomotor domains were 0.86, 0.79, 0.79 and 0.70, and 0.90 for the full scale of MENQOL. PCA revealed a four-factorial model. Diabetes and non-diabetes subjects experienced their first period (13.25 vs. 13.10 years, p = 0.680) and achieved menopause around the same age (49.35 vs. 48.87 years, p = 0.426). We found significant variations in the MENQOL's PHS and PS domain scores that could be explained by SF-12 PCS (25%) and SF-12 MCS (20%) sub-scales. The validity of the MENQOL domains was demonstrated through significant associations with the equivalent SF-12 MCS and PCS subscales. The PS domain of the MENQOL also predicted the likelihood of symptoms of depression (1.42, 95% confidence interval 1.01-2.02). CONCLUSIONS: This study confirms the validity and internal consistency of the MENQOL questionnaire for measuring quality of life in postmenopausal women with diabetes, suggesting that the instrument can be used to screen people for menopausal symptoms

    A Profile Likelihood Analysis of the Constrained MSSM with Genetic Algorithms

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    The Constrained Minimal Supersymmetric Standard Model (CMSSM) is one of the simplest and most widely-studied supersymmetric extensions to the standard model of particle physics. Nevertheless, current data do not sufficiently constrain the model parameters in a way completely independent of priors, statistical measures and scanning techniques. We present a new technique for scanning supersymmetric parameter spaces, optimised for frequentist profile likelihood analyses and based on Genetic Algorithms. We apply this technique to the CMSSM, taking into account existing collider and cosmological data in our global fit. We compare our method to the MultiNest algorithm, an efficient Bayesian technique, paying particular attention to the best-fit points and implications for particle masses at the LHC and dark matter searches. Our global best-fit point lies in the focus point region. We find many high-likelihood points in both the stau co-annihilation and focus point regions, including a previously neglected section of the co-annihilation region at large m_0. We show that there are many high-likelihood points in the CMSSM parameter space commonly missed by existing scanning techniques, especially at high masses. This has a significant influence on the derived confidence regions for parameters and observables, and can dramatically change the entire statistical inference of such scans.Comment: 47 pages, 8 figures; Fig. 8, Table 7 and more discussions added to Sec. 3.4.2 in response to referee's comments; accepted for publication in JHE

    Challenges of Profile Likelihood Evaluation in Multi-Dimensional SUSY Scans

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    Statistical inference of the fundamental parameters of supersymmetric theories is a challenging and active endeavor. Several sophisticated algorithms have been employed to this end. While Markov-Chain Monte Carlo (MCMC) and nested sampling techniques are geared towards Bayesian inference, they have also been used to estimate frequentist confidence intervals based on the profile likelihood ratio. We investigate the performance and appropriate configuration of MultiNest, a nested sampling based algorithm, when used for profile likelihood-based analyses both on toy models and on the parameter space of the Constrained MSSM. We find that while the standard configuration is appropriate for an accurate reconstruction of the Bayesian posterior, the profile likelihood is poorly approximated. We identify a more appropriate MultiNest configuration for profile likelihood analyses, which gives an excellent exploration of the profile likelihood (albeit at a larger computational cost), including the identification of the global maximum likelihood value. We conclude that with the appropriate configuration MultiNest is a suitable tool for profile likelihood studies, indicating previous claims to the contrary are not well founded.Comment: 21 pages, 9 figures, 1 table; minor changes following referee report. Matches version accepted by JHE

    Fine-tuning implications for complementary dark matter and LHC SUSY searches

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    The requirement that SUSY should solve the hierarchy problem without undue fine-tuning imposes severe constraints on the new supersymmetric states. With the MSSM spectrum and soft SUSY breaking originating from universal scalar and gaugino masses at the Grand Unification scale, we show that the low-fine-tuned regions fall into two classes that will require complementary collider and dark matter searches to explore in the near future. The first class has relatively light gluinos or squarks which should be found by the LHC in its first run. We identify the multijet plus E_T^miss signal as the optimal channel and determine the discovery potential in the first run. The second class has heavier gluinos and squarks but the LSP has a significant Higgsino component and should be seen by the next generation of direct dark matter detection experiments. The combined information from the 7 TeV LHC run and the next generation of direct detection experiments can test almost all of the CMSSM parameter space consistent with dark matter and EW constraints, corresponding to a fine-tuning not worse than 1:100. To cover the complete low-fine-tuned region by SUSY searches at the LHC will require running at the full 14 TeV CM energy; in addition it may be tested indirectly by Higgs searches covering the mass range below 120 GeV.Comment: References added. Version accepted for publication in JHE

    Anaesthesia for serial whole-lung lavage in a patient with severe pulmonary alveolar proteinosis: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>Pulmonary alveolar proteinosis is a rare condition that requires treatment by whole-lung lavage. We report a case of severe pulmonary alveolar proteinosis and discuss a safe and effective strategy for the anaesthetic management of patients undergoing this complex procedure.</p> <p>Case presentation</p> <p>A 34-year-old Caucasian man was diagnosed with severe pulmonary alveolar proteinosis. He developed severe respiratory failure and subsequently underwent serial whole-lung lavage. Our anaesthetic technique included the use of pre-oxygenation, complete lung separation with a left-sided double-lumen endotracheal tube, one-lung ventilation with positive end-expiratory pressure, appropriate ventilatory monitoring, cautious use of positional manoeuvres and single-lumen endotracheal tube exchange for short-term postoperative ventilation.</p> <p>Conclusion</p> <p>Patients with pulmonary alveolar proteinosis may present with severe respiratory failure and require urgent whole-lung lavage. We have described a safe and effective strategy for anaesthesia for whole-lung lavage. We recommend our anaesthetic technique for patients undergoing this complex and uncommon procedure.</p

    Phenomenological Aspects of Gauge Mediation with Sequestered Supersymmetry Breaking in light of Dark Matter Detection

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    In a recent work, a model of gauge mediation with sequestered supersymmetry (SUSY) breaking was proposed. In this model, the mass of the gravitino is O(100) GeV without causing the flavor-changing neutral-current problem. In contrast to traditional gauge mediation, the gravitino is not the lightest SUSY particle and the neutralino is the candidate of the dark matter. In this paper, we investigate phenomenological aspects of this model and discuss the possibility of the direct detection of the dark matter. In particular, we focus on the light neutralino case and find that the light-Higgsino scenario such as the focus point is interesting, taking account of the recent CDMS result.Comment: 17 pages, 8 figures; v2:references added, some corrections; v3:version accepted for publication in JHE

    Proteinase-activated receptor 4 stimulation-induced epithelial-mesenchymal transition in alveolar epithelial cells

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    BACKGROUND: Proteinase-activated receptors (PARs; PAR(1–4)) that can be activated by serine proteinases such as thrombin and neutrophil catepsin G are known to contribute to the pathogenesis of various pulmonary diseases including fibrosis. Among these PARs, especially PAR(4), a newly identified subtype, is highly expressed in the lung. Here, we examined whether PAR(4 )stimulation plays a role in the formation of fibrotic response in the lung, through alveolar epithelial-mesenchymal transition (EMT) which contributes to the increase in myofibroblast population. METHODS: EMT was assessed by measuring the changes in each specific cell markers, E-cadherin for epithelial cell, α-smooth muscle actin (α-SMA) for myofibroblast, using primary cultured mouse alveolar epithelial cells and human lung carcinoma-derived alveolar epithelial cell line (A549 cells). RESULTS: Stimulation of PAR with thrombin (1 U/ml) or a synthetic PAR(4 )agonist peptide (AYPGKF-NH(2), 100 μM) for 72 h induced morphological changes from cobblestone-like structure to elongated shape in primary cultured alveolar epithelial cells and A549 cells. In immunocytochemical analyses of these cells, such PAR(4 )stimulation decreased E-cadherin-like immunoreactivity and increased α-SMA-like immunoreactivity, as observed with a typical EMT-inducer, tumor growth factor-β (TGF-β). Western blot analyses of PAR(4)-stimulated A549 cells also showed similar changes in expression of these EMT-related marker proteins. Such PAR(4)-mediated changes were attenuated by inhibitors of epidermal growth factor receptor (EGFR) kinase and Src. PAR(4)-mediated morphological changes in primary cultured alveolar epithelial cells were reduced in the presence of these inhibitors. PAR(4 )stimulation increased tyrosine phosphorylated EGFR or tyrosine phosphorylated Src level in A549 cells, and the former response being inhibited by Src inhibitor. CONCLUSION: PAR(4 )stimulation of alveolar epithelial cells induced epithelial-mesenchymal transition (EMT) as monitored by cell shapes, and epithelial or myofibroblast marker at least partly through EGFR transactivation via receptor-linked Src activation

    Proteomics: in pursuit of effective traumatic brain injury therapeutics

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    Effective traumatic brain injury (TBI) therapeutics remain stubbornly elusive. Efforts in the field have been challenged by the heterogeneity of clinical TBI, with greater complexity among underlying molecular phenotypes than initially conceived. Future research must confront the multitude of factors comprising this heterogeneity, representing a big data challenge befitting the coming informatics age. Proteomics is poised to serve a central role in prescriptive therapeutic development, as it offers an efficient endpoint within which to assess post-TBI biochemistry. We examine rationale for multifactor TBI proteomic studies and the particular importance of temporal profiling in defining biochemical sequences and guiding therapeutic development. Lastly, we offer perspective on repurposing biofluid proteomics to develop theragnostic assays with which to prescribe, monitor and assess pharmaceutics for improved translation and outcome for TBI patients

    Structural, thermal and dissolution properties of MgO- and CaO-containing borophosphate glasses: effect of Fe2O3 addition

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    This paper investigated manufacture of high-durability phosphate glass fibres for biomedical applications. Five different borophosphate glass formulations in the systems of 45P2O5–5B2O3–5Na2O–(29 − x)CaO–16MgO–(x)Fe2O3 and 45P2O5–5B2O3–5Na2O–24CaO–(21 − x)MgO–(x)Fe2O3 where x = 5, 8 and 11 mol% were produced via melt quenching. The compositions and amorphous nature of the glasses were confirmed by ICP-MS and XRD, respectively. FTIR results indicated depolymerisation of the phosphate chains with a decrease in Q2 units with increasing Fe2O3 content. DSC analyses showed an increase in Tg by ~5 °C with an increment of 3 mol% in Fe2O3 content. The thermal properties were also used to calculate processing window (i.e. Tc,ons—Tg) and another parameter, Kgl, to determine the suitability for fibre drawing directly from melt, which equals (Tc,ons—Tg)/(Tl—Tc,ons). The degradation study conducted in PBS solution at 37 °C showed a decrease of 25–47% in degradation rate with increasing Fe2O3 content. This confirmed that the chemical durability of the glasses had increased, which was suggested to be due to Fe2O3 addition. Furthermore, the density measured via Archimedes method revealed a linear increase with increasing Fe2O3 content
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