143 research outputs found

    Quaternary ferrites by batch and continuous flow hydrothermal synthesis: a comparison

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    Crystalline spinel quaternary ferrites MxZn1−xFe2O4 (M = Co, Ni; x = 0.2, 0.35, 0.5, 0.65, 0.8) were synthesised through conventional batch hydrothermal synthesis (HT) at 135 °C as well as via continuous flow hydrothermal synthesis (CHFS). The as prepared compounds were thoroughly characterised from a compositional (ICP-MS, XPS) and structural (XRD) point of view in order to compare the synthetic approaches and achieve a greater understanding of how the chosen approach influences the characteristics of the resulting spinel

    Relationship between antidepressant therapy and risk for cardiovascular events in patients with and without cardiovascular disease

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    Objective: The American Heart Association has endorsed depression as a cardiac risk factor and recommends screening as part of routine practice. This has been met with controversy due to inconsistencies in the data linking depression treatment to better cardiovascular outcomes. Our objective was to prospectively assess the association between depression treatment (defined as being prescribed antidepressant medication) and major adverse cardiovascular events (MACE) in patients referred for exercise stress tests. Methods: 2385 consecutive patients presenting for myocardial perfusion exercise stress tests underwent a sociodemographic, medical, and psychiatric interview (PRIME-MD) and completed the Beck Depression Inventory (BDI). History of CVD and antidepressant use was self-reported and verified via chart review. Participants followed over an 8.8 year follow-up, and information regarding MACE incidence (including cardiac mortality, non-fatal myocardial infarction, revascularization procedures, cerebrovascular events) was obtained from provincial administrative databases. Results: 8% (n=190) of the sample were taking antidepressants at baseline, 41% (n=916) had a history of CVD, and 38.7% (n=921) had depression according to the PRIME-MD or BDI. Antidepressant treatment was associated with a 30% reduced risk of MACE (HR=0.697; 95%CI=0.504-0.964; p=.029). A 46% reduction in risk was associated with antidepressant treatment among those without CVD (HR=0.542; 95%CI=0.299-0.981; p=.043). In depressed patients, a 33% reduction in risk of MACE associated with antidepressant use was seen (adjusted HR=0.674; 95%CI=0.440-1.033; p=.07). Conclusions: Antidepressants may be cardio-protective among patients presenting for stress testing independent of risk factors including CVD and depression. Results support treating depression with antidepressants in this population to reduce risk of MACE

    Evaluating the impact of fluorination on the electro-optical properties of cross-conjugated benzobisoxazoles

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    Published as part of The Journal of Physical Chemistry virtual special issue “William M. Jackson Festschrift”.Six 2,4,6,8-tetrarylbenzo[1,2-d:4,5-d′]bisoxazoles (BBOs) were synthesized: three bearing phenyl substituents at the 2- and 6-positions and three bearing perfluorophenyl groups at those positions. The influence of perfluoro-aryl group substitution on the physical, optical, and electronic properties of 2,4,6,8-tetrarylbenzo[1,2-d:4,5-d′]bisoxazoles (BBO) was evaluated using both experimental and theoretical methods. The density functional theory (DFT) model was found to be well-matched to the experimental optical data, as evidenced by the UV–vis spectra. Both cyclic voltammetry (CV) and ultraviolet photoelectron spectroscopy (UPS) were used to determine the position of the HOMO with varying results. The values obtained by CV were deeper than those obtained via UPS and correlated well with the theoretical calculations. However, the UPS values were more consistent with the expected outcomes for a system with segregated frontier molecular orbitals (FMOs). The UPS results are also supported by the electrostatic potential maps, which indicate that the electron density within the LUMO and HOMO is nearly completely localized along the 2,6- or 4,8-axis, respectively. The summation of the results indicates that strongly electron-withdrawing groups can be used to selectively tune the LUMO level with minor perturbation of the HOMO, something that is challenging to accomplish in typical donor–acceptor systems.We thank Dr. Norman Lee, Stephon Betts, and Dr. Paul Ralifo from the Chemical Instrumentation Facility at Boston University for compound analysis. We also thank Margaret Chern from the Dennis Lab at Boston University for assistance in obtaining fluorescence lifetimes and quantum yields. Next, we thank Volodimyr Duzhko at the Center for Electronic Materials and Devices at the University of Massachusetts-Amherst. We also thank the National Science Foundation (CHE-141373, CHE-1640298, and CHE-1413207) as well a supercomputer allocation by the Extreme Science and Engineering Discovery Environment (XSEDE) for the Comet supercomputer cluster provided by the San Diego Supercomputing Center (DMR-160146) for supporting this work. (CHE-141373 - National Science Foundation; CHE-1640298 - National Science Foundation; CHE-1413207 - National Science Foundation)Accepted manuscrip

    Drug-drug interactions between palbociclib and proton pump inhibitors may significantly affect clinical outcome of metastatic breast cancer patients

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    BACKGROUND: Proton-pump-inhibitors (PPIs) are frequently prescribed for the management of anticancer drug-related gastrointestinal symptoms. Palbociclib is a weak base with pH-dependent solubility and potential drug-drug interaction at the absorption level may affect clinical pharmacokinetics. The current study was aimed at investigating the effect of co-administration of PPIs and palbociclib on progression-free survival (PFS) in metastatic breast cancer (mBC) patients. PATIENTS AND METHODS: Patients affected by estrogen receptor-positive, human epidermal growth factor receptor 2-negative mBC, who were candidates for first-line treatment with palbociclib, were enrolled in this retrospective observational study. Patients were defined as ‘no concomitant PPIs’ if no PPIs were administered during palbociclib treatment, and as ‘concomitant PPIs’ if the administration of PPIs covered the entire or not less than two-thirds of treatment with palbociclib. All clinical interventions were made according to clinical practice. RESULTS: A total of 112 patients were enrolled in the study; 56 belonged to the ‘no concomitant PPIs’ group and 56 to the ‘concomitant PPIs’ group. Seventy-one patients were endocrine-sensitive and received palbociclib and letrozole, and 43 were endocrine-resistant and were treated with palbociclib and fulvestrant. The most prescribed PPI was lansoprazole. Patients taking PPIs had a shorter PFS than those taking palbociclib and endocrine therapy alone (14.0 versus 37.9 months, P 2 hematological toxicities [Common Terminology Criteria for Adverse Events (CTCAE) scale]. CONCLUSIONS: The present study demonstrates that concomitant use of PPIs in mBC patients treated with palbociclib has a detrimental effect on PFS. Therefore, it is recommended to prescribe PPIs with caution in these patients, strictly adhering to the indications in the summary of product characteristics (RCP)

    Avalanches in Breakdown and Fracture Processes

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    We investigate the breakdown of disordered networks under the action of an increasing external---mechanical or electrical---force. We perform a mean-field analysis and estimate scaling exponents for the approach to the instability. By simulating two-dimensional models of electric breakdown and fracture we observe that the breakdown is preceded by avalanche events. The avalanches can be described by scaling laws, and the estimated values of the exponents are consistent with those found in mean-field theory. The breakdown point is characterized by a discontinuity in the macroscopic properties of the material, such as conductivity or elasticity, indicative of a first order transition. The scaling laws suggest an analogy with the behavior expected in spinodal nucleation.Comment: 15 pages, 12 figures, submitted to Phys. Rev. E, corrected typo in authors name, no changes to the pape

    Psychosocial care for adult cancer patients: guidelines of the Italian Medical Oncology Association

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    SIMPLE SUMMARY: People with cancer often experience psychological and social needs, related to their disease and treatments, that can negatively impact quality of life. Various social interventions can be helpful but are not always offered to patients who would benefit from them. This guideline aims to help oncology professionals address the psychosocial aspects of their adult patients and of those who care for them. It was compiled by a multidisciplinary panel, including patients, using rigorous methodology. Topics include patient information and communication, screening and management of psychosocial needs, and caregiver support. In particular, evidence emphasizes that nurses play a central role in providing psychosocial care and information for cancer patients, and that Physician communication skills must be improved with specific evidence-based training. In addition, psychosocial needs must be promptly detected and managed, especially with appropriate non-pharmacological interventions. ABSTRACT: Psychosocial morbidity can have negative consequences for cancer patients, including maladaptive coping, poor treatment adherence, and lower quality of life. Evidence shows that psychosocial interventions can positively impact quality of life, as well as symptoms and side effects; however, they are not always offered to patients who might benefit from them. These guidelines were produced by a multidisciplinary panel of 16 experts, including patients, following GRADE methodology. The panel framed clinical questions and voted on outcomes to investigate. Studies identified by rigorous search strategies were assessed to rate certainty of evidence, and recommendations were formulated by the panel. Although the quality of the evidence found was generally moderate, interventions could be recommended aimed at improving patient information, communication with healthcare professionals and involvement in decision-making; detecting and managing patient psychosocial needs, particularly with non-pharmacological therapy; and supporting families of patients with advanced cancer. The role of nurses as providers of information and psychosocial care is stressed. Most recommended interventions do not appear to necessitate new services or infrastructures, and therefore do not require allocation of additional resources, but predominantly involve changes in clinical staff behavior and/or ward organization. Patients should be made aware of psychosocial care standards so that they can expect to receive them

    Tri-critical behavior in rupture induced by disorder

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    We discover a qualitatively new behavior for systems where the load transfer has limiting stress amplification as in real fiber composites. We find that the disorder is a relevant field leading to tri--criticality, separating a first-order regime where rupture occurs without significant precursors from a second-order regime where the macroscopic elastic coefficient exhibit power law behavior. Our results are based on analytical analysis of fiber bundle models and numerical simulations of a two-dimensional tensorial spring-block system in which stick-slip motion and fracture compete.Comment: Revtex, 10 pages, 4 figures available upon reques
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