2,610 research outputs found

    Plutarch’s Alexander: an Endorsement of Platonism and Living as a Philosopher

    Get PDF
    Man has often had an inclination to promote his way of living to his fellow man. Believing that his way of approaching life is superior to all others, he has defended and enforced his views against and upon others. He has done this by way of reasoning and by way of violence. Although most instances of this natural desire are recognized in the form of wars and acts of violence, there have also been many other prominent instances involving peaceful reasoning, such as the revolutionary movements of Martin Luther King Jr. and Gandhi. Plutarch, a Greco-Roman historian and writer, is one noteworthy figure who also sought to persuade others through peaceful methods, specifically through his writing. What has enabled his name to be remembered through the centuries has undoubtedly been his greatest work, Lives of the Noble Grecians and Romans, a work more commonly referred to as Parallel Lives. By examining this book, and the account on Alexander the Great in particular, readers can discover a peaceful and effective means of spreading their beliefs to others. Through witty rhetoric and other persuasive writing techniques, readers will learn how Plutarch uses Alexander’s celebrity status of the time to promote Platonism, a popular school of thought following the teachings of Plato, and living the life of a philosopher. Why Plutarch wants to promote Platonism, the life of a philosopher is also explored in this analysis, and corroborated through several Classical period historians. Finally, Plutarch’s attempt to paint Alexander as a Platonist and a worthy idol representing all philosophers will open the reader to a few new fundamental beliefs from a distant era of the past regarding living an ethical, self-governed, and virtuous life

    Galactic conformity measured in semi-analytic models

    Get PDF
    We study the correlation between the specific star formation rate of central galaxies and neighbour galaxies, also known as 'galactic conformity', out to 20 Mpc/h using three semi-analytic models (SAMs, one from L-GALAXIES and other two from GALFORM). The aim is to establish whether SAMs are able to show galactic conformity using different models and selection criteria. In all the models, when the selection of primary galaxies is based on an isolation criterion in real space, the mean fraction of quenched galaxies around quenched primary galaxies is higher than that around star-forming primary galaxies of the same stellar mass. The overall signal of conformity decreases when we remove satellites selected as primary galaxies, but the effect is much stronger in GALFORM models compared with the L-GALAXIES model. We find this difference is partially explained by the fact that in GALFORM once a galaxy becomes a satellite remains as such, whereas satellites can become centrals at a later time in L-GALAXIES. The signal of conformity decreases down to 60% in the L-GALAXIES model after removing central galaxies that were ejected from their host halo in the past. Galactic conformity is also influenced by primary galaxies at fixed stellar mass that reside in dark matter haloes of different masses. Finally, we explore a proxy of conformity between distinct haloes. In this case the conformity is weak beyond ~ 3 Mpc/h (<3% in L-GALAXIES, <1-2% in GALFORM models). Therefore, it seems difficult that conformity is directly related with a long-range effect.Comment: 15 pages, 7 figures. Accepted for publication in MNRA

    A Dual-Mixed Approximation for a Huber Regularization of Generalized pp-Stokes Viscoplastic Flow Problems

    Full text link
    In this paper, we propose a dual-mixed formulation for stationary viscoplastic flows with yield, such as the Bingham or the Herschel-Bulkley flow. The approach is based on a Huber regularization of the viscosity term and a two-fold saddle point nonlinear operator equation for the resulting weak formulation. We provide the uniqueness of solutions for the continuous formulation and propose a discrete scheme based on Arnold-Falk-Winther finite elements. The discretization scheme yields a system of slantly differentiable nonlinear equations, for which a semismooth Newton algorithm is proposed and implemented. Local superlinear convergence of the method is also proved. Finally, we perform several numerical experiments in two and three dimensions to investigate the behavior and efficiency of the method

    Two-loop critical mass for Wilson fermions

    Get PDF
    We have redone a recent two-loop computation of the critical mass for Wilson fermions in lattice QCD by evaluating Feynman integrals with the coordinate-space method. We present the results for different types of infrared regularization. We confirm both the previous numerical estimates and the power of the coordinate-space method whenever high accuracy is needed.Comment: 13 LaTeX2e pages, 2 ps figures include

    Ultraviolet-A Light and Riboflavin Therapy for Acanthamoeba Keratitis: A Case Report

    Get PDF
    Purpose: To report ultraviolet-A (UV-A) light treatment in a patient with Acanthamoeba keratitis (AK). Methods: Interventional case report. A standard protocol for ultraviolet corneal therapy, with a power emission of 3 mW/cm2 and a wavelength of 370 nm, was used. The protocol included an 8-nm bandwidth at a 54-mm distance measured with a collimation system of diodes as well as a protective shield of riboflavin in a case of documented AK. Results: A 54-year-old female patient with AK, showing no therapeutic response to a wide variety of topical antimicrobial agents and with a visual acuity of 20/400, was treated with UV-A therapy. The patient displayed a favourable response in the first 24 h after treatment, with improvement of symptoms, visual acuity (to 20/200) and biomicroscopy cornea with haze degree I. By the third week post-treatment, the patient was symptom-free. Her visual acuity was 20/30, and the affected cornea was clear. Five months after treatment, there had been no recurrence, and her vision was 20/20. Conclusions: Treatment with UV-A light was an effective therapy in this case of AK

    Gen-Z ambassadors: students supporting persons with Alzheimer’s disease and their caregivers in the Rio Grande Valley

    Get PDF
    Background: Youth participation in policy, research, education and community development initiatives is a right embedded in the United Nations Convention on the Rights of the Child (UNCRC, General Assembly, 1989). However, avenues for youth participation in health promotion and care remains limited. Our Ambassadors program prepares high-school students on the Texas-Mexico border to understand and empathize with persons with Alzheimer’s disease (PwAD) and to empower their family and caregivers, consummating the UNCRC in the service of transformative community change actions. Methods: Our long-term objective is youth participation, defined as practices that involve collaboration between students and various community stakeholders in AD. The initial phase of the program is the design of a curriculum for early high school students to develop the knowledge, skills and attitudes required for that participation. We used a cooperative strategy (a high school students-faculty collaborative), guided by empowerment and ecological theories to achieve optimal youth advancement in the context of the UNCRC social, health and cultural rights of children. Results: The GenZ Ambassadors curricular units were identified through an iterative process in which faculty documented their activities with youth and tested sessions ranging from the biological basis and clinical presentations of AD to family impact, principles of caregiving, youth as change agents, building intergenerational partnerships, and self-reflection exercises. Ambassadors selected settings and strategies designed to empower their peers and to transform communities by skill and confidence building. Discussion: The process implemented and content analysis revealed a variety of themes that benefited persons with AD and their caregivers in the Rio Grande Valley. Several strategies will be tested to generate interactive training materials and culturally and age-competent as well as delivery strategies, including peer-to-peer delivery

    The Carnegie Supernova Project: The Low-Redshift Survey

    Full text link
    Supernovae are essential to understanding the chemical evolution of the Universe. Type Ia supernovae also provide the most powerful observational tool currently available for studying the expansion history of the Universe and the nature of dark energy. Our basic knowledge of supernovae comes from the study of their photometric and spectroscopic properties. However, the presently available data sets of optical and near-infrared light curves of supernovae are rather small and/or heterogeneous, and employ photometric systems that are poorly characterized. Similarly, there are relatively few supernovae whose spectral evolution has been well sampled, both in wavelength and phase, with precise spectrophotometric observations. The low-redshift portion of the Carnegie Supernova Project (CSP) seeks to remedy this situation by providing photometry and spectrophotometry of a large sample of supernovae taken on telescope/filter/detector systems that are well understood and well characterized. During a five-year program which began in September 2004, we expect to obtain high-precision u'g'r'i'BVYJHKs light curves and optical spectrophotometry for about 250 supernovae of all types. In this paper we provide a detailed description of the CSP survey observing and data reduction methodology. In addition, we present preliminary photometry and spectra obtained for a few representative supernovae during the first observing campaign.Comment: 45 pages, 13 figures, 3 tables, accepted by PAS

    The Carnegie Supernova Project: Analysis of the First Sample of Low-Redshift Type-Ia Supernovae

    Get PDF
    We present the analysis of the first set of low-redshift Type Ia supernovae (SNe Ia) by the Carnegie Supernova Project. Well-sampled, high-precision optical (ugriBV) and near-infrared (NIR; YJHKs) light curves obtained in a well-understood photometric system are used to provide light-curve parameters, and ugriBVYJH template light curves. The intrinsic colors at maximum light are calibrated to compute optical--NIR color excesses for the full sample, thus allowing the properties of the reddening law in the host galaxies to be studied. A low value of Rv~1.7, is derived when using the entire sample of SNe. However, when the two highly reddened SNe in the sample are excluded, a value Galactic standard of Rv~3.2 is obtained. The colors of these two events are well matched by a reddening model due to circumstellar dust. The peak luminosities are calibrated using a two-parameter linear fit to the decline rates and the colors, or alternatively, the color excesses. In both cases, dispersions in absolute magnitude of 0.12--0.16 mag are obtained, depending on the filter-color combination. In contrast to the results obtained from color excesses, these fits give Rv~1--2, even when the two highly reddened SNe are excluded. This discrepancy suggests that, beyond the "normal" interstellar reddening produced in the host galaxies, there is an intrinsic dispersion in the colors of SNe Ia which is correlated with luminosity but independent of the decline rate. Finally, a Hubble diagram is produced by combining the results of the fits for each filter. The resulting scatter of 0.12 mag appears to be limited by peculiar velocities as evidenced by the strong correlation between the distance-modulus residuals among the different filters. The implication is that the actual precision of SN Ia distances is 3--4%.Comment: 76 pages, 20 figures, accepted for publication in A

    A Critical Review on Al-Co Alloys: Fabrication Routes, Microstructural Evolution and Properties

    Get PDF
    Al-Co alloys is an emerging category of metallic materials with promising properties and potential application in various demanding environments. Over the years, different manufacturing techniques have been employed to fabricate Al-Co alloys, spanning from conventional casting to rapid solidification techniques, such as melt spinning, thus leading to a variety of different microstructural features. The effect of the fabrication method on the microstructure is crucial, affecting the morphology and volume of the precipitates, the formation of supersaturated solid solutions and the development of amorphous phases. In addition, the alloy composition has an effect on the type and volume fraction of intermetallic phases formed. As a result, alloy properties are largely affected by the microstructural outcomes. This review focuses on highlighting the effect of the fabrication techniques and composition on the microstructure and properties of Al-Co alloys. Another goal is to highlight areas in the field that are not well understood. The advantages and limitations of this less common category of Al alloys are being discussed with the scope of future prospects and potential applications

    Metastatic pheochromocytoma to liver without elevation of metanephrines and catecholamines

    Get PDF
    AbstractIntroductionMalignant pheochromocytoma represents 10% of all patients with pheochromocytoma. Of these cases, only 5–9% presents without elevation of metanephrines and catecholamines.Presentation of caseA 43-year-old female patient presented with an abdominal tumor. An exploratory laparotomy was performed and the final report was a pheochromocytoma. After ten years, multiple liver lesions were detected and surgical treatment was performed. Pathological evaluation revealed a malignant pheochromocytoma with negative margins after 5 years of follow-up without evidence of disease.DiscussionThe recurrence rate of malignant pheochromocytoma is 15–20% at ten years and a 5-year survival rate that ranges from 50% to 80%. The presence of synchronous metastases is rare (10–27%), but have been reported until 20 years later with the most common metastatic sites being the local lymph nodes, bone (50%), liver (50%) and lung (30%). The prognostic factor such as size >6cm, age over 45 years, synchronous metastasis and no tumor excision are related with poor prognosis.ConclusionSurgical treatment offers the best survival rate and the only chance of cure so far and the goal is an R0 resection as in our case. So it should be the treatment of choice
    corecore