Learning from books

Alan H. Goldman on the philosophical value of the nove

Zero field magnetic phase transitions and anomalous low temperature upturn in resistivity of single crystalline α-TmAlB4

In this study, pure α-TmAlB4 (YCrB4structure)single crystals were grown with no β-TmAlB4 (ThMoB4structure) intergrowth, and zero magnetic fieldtransitions were confirmed through specific heat capacity, magnetization, and electric resistivity measurements. The anomalous magnetic transition was found at approximately 6.2 K with long range antiferromagnetictransition at 5.6 K. The difference in field dependence between these two transitions indicates that they do not share a common magnetic origin. In addition, we investigated electrical resistivity down to 20 mK, and found upturn behavior at around 0.8 K. The low temperature upturn anomaly in resistivity was not found for other compounds of investigation for RAlB4 (R=rare earth elements), which suggests that an α-RAlB4system has a significantly different ground state, compared to a β-RAlB4 system

Survival of a Diffusing Particle in a Transverse Shear Flow: A First-Passage Problem with Continuously Varying Persistence Exponent

We consider a particle diffusing in the y-direction, dy/dt=\eta(t), subject to a transverse shear flow in the x-direction, dx/dt=f(y), where x \ge 0 and x=0 is an absorbing boundary. We treat the class of models defined by f(y) = \pm v_{\pm}(\pm y)^\alpha where the upper (lower) sign refers to y>0 (y<0). We show that the particle survives with probability Q(t) \sim t^{-\theta} with \theta = 1/4, independent of \alpha, if v_{+}=v_{-}. If v_{+} \ne v_{-}, however, we show that \theta depends on both \alpha and the ratio v_{+}/v_{-}, and we determine this dependence.Comment: 4 page

Epithelioid Glioblastoma Presenting as Aphasia in a Young Adult with Ovarian Cancer: A Case Report

Background: Epithelioid glioblastoma (eGBM) is a recent addition to the World Health Organization’s classification of central nervous system (CNS) tumors. This rare lesion has a predilection for younger patients, can mimic metastatic disease on preoperative imaging and intraoperative pathology, and portends a poor prognosis due to propensity for leptomeningeal dissemination. Case Description: We discuss a case of a young woman with a history of ovarian cancer who presented with seizure and a new ring-enhancing left temporal brain lesion. The patient underwent gross-total surgical resection of this lesion, during which frozen section suggested metastasis. However, pathologic interrogation showed pleomorphic epithelioid cells and glial fibrillary acid positivity, suggesting eGBM. The patient has since completed radiotherapy and six-month post-operative imaging has not revealed recurrence or leptomeningeal dissemination. Conclusion: Our patient\u27s clinical history and pre-operative radiographic evaluation suggested CNS metastatic disease. Ultimately, final pathology revealed eGBM, a newly classified CNS primary tumor. This reinforces the importance of direct tissue sampling and including eGBM on the differential for young patients with histories of systemic cancer presenting with new CNS lesions

Photolithography Process Characterization and 3D Simulation Using Track-Mounted Development Rate Monitor Data

A track-mounted, in-situ Dissolution Rate Monitor (DRM) is used to study the impact of exposure variations on g-line, i-line and DUV positive chemically-amplified resists. In the i-line case, a comparative study between constant spray and a spray/puddle process was undertaken. In all cases, modeling parameters were extracted from the track-mounted DRM data and entered into 2D and 3D simulators using an experimentally-generated Development Rate vs. PAC concentration table. Simulated profiles were compared with actual SEM cross-sections. Whenever possible, DRM traces were used to analyze standing waves, surface inhibition effects and quantify resist performance by calculating contrast. For the g-line case, the impact of PEB temperature upon the standing wave effects, as quantified by the in-situ DRM data, was studied

Epithelioid Glioblastoma Presenting as Aphasia in a Young Adult with Ovarian Cancer: A Case Report

Our patient\u27s clinical history and preoperative radiographic evaluation suggested central nervous system (CNS) metastatic disease. Ultimately, final pathology revealed epithelioid glioblastoma (eGBM), a newly classified CNS primary tumor. This reinforces the importance of direct tissue sampling and including eGBM on the differential for young patients with histories of systemic cancer presenting with new CNS lesions

Spin dynamics near a putative antiferromagnetic quantum critical point in Cu substituted BaFe2_2As2_2 and its relation to high-temperature superconductivity

We present the results of elastic and inelastic neutron scattering measurements on non-superconducting Ba(Fe${_{0.957}}$Cu${_{0.043}}$)${_2}$As${_2}$, a composition close to a quantum critical point between AFM ordered and paramagnetic phases. By comparing these results with the spin fluctuations in the low Cu composition as well as the parent compound BaFe$_2$As$_2$ and superconducting Ba(Fe$_{1-x}$Ni$_x$)$_2$As$_2$ compounds, we demonstrate that paramagnon-like spin fluctuations are evident in the antiferromagnetically ordered state of Ba(Fe$_{0.957}$Cu$_{0.043}$)$_2$As$_2$, which is distinct from the AFM-like spin fluctuations in the superconducting compounds. Our observations suggest that Cu substitution decouples the interaction between quasiparticles and the spin fluctuations. We also show that the spin-spin correlation length, ${\xi(T)}$, increases rapidly as the temperature is lowered and find ${\omega/T}$ scaling behavior, the hallmark of quantum criticality, at an antiferromagnetic quantum critical point.Comment: 10 pages, 7 figure

Elective affinities of the Protestant ethic : Weber and the chemistry of capitalism

Peer reviewedPostprin

The FReedom from Ischemic Events - New Dimensions for Survival (FRIENDS) registry: design of a prospective cohort study of patients with advanced peripheral artery disease

Background: Advanced lower extremity peripheral artery disease (PAD), whether presenting as acute limb ischemia (ALI) or chronic critical limb ischemia (CLI), is associated with high rates of cardiovascular ischemic events, amputation, and death. Past research has focused on strategies of revascularization, but few data are available that prospectively evaluate the impact of key process of care factors (spanning pre-admission, acute hospitalization, and post-discharge) that might contribute to improving short and long-term health outcomes. Methods/Design The FRIENDS registry is designed to prospectively evaluate a range of patient and health system care delivery factors that might serve as future targets for efforts to improve limb and systemic outcomes for patients with ALI or CLI. This hypothesis-driven registry was designed to evaluate the contributions of: (i) pre-hospital limb ischemia symptom duration, (ii) use of leg revascularization strategies, and (iii) use of risk-reduction pharmacotherapies, as pre-specified factors that may affect amputation-free survival. Sequential patients would be included at an index “vascular specialist-defined” ALI or CLI episode, and patients excluded only for non-vascular etiologies of limb threat. Data including baseline demographics, functional status, co-morbidities, pre-hospital time segments, and use of medical therapies; hospital-based use of revascularization strategies, time segments, and pharmacotherapies; and rates of systemic ischemic events (e.g., myocardial infarction, stroke, hospitalization, and death) and limb ischemic events (e.g., hospitalization for revascularization or amputation) will be recorded during a minimum of one year follow-up. Discussion The FRIENDS registry is designed to evaluate the potential impact of key factors that may contribute to adverse outcomes for patients with ALI or CLI. Definition of new “health system-based” therapeutic targets could then become the focus of future interventional clinical trials for individuals with advanced PAD