Economic on El Paso del Norte (Part 1)

Mexico ; Trade barriers

MRI sequences for detection of acute pulmonary embolism

In recent years a range of imaging techniques have emerged to help diagnose patients with suspected acute Pulmonary Embolism (PE). This is particularly useful for those who are contraindicated (renal failure or allergies) to the contrast media that is needed to perform Computed Tomography Pulmonary Angiography (CTPA), which would be the usual diagnostic tool of choice. To aid the cohort of patients with this contraindication, we have investigated the option of using Magnetic Resonance Imaging (MRI) to diagnose PE. In this thesis, MRI sequences including gradient recall echo (more specifically balanced Steady State Free Precession [b-SSFP]) with different trajectories of data sampling, and diffusion weighted imaging (DWI) were assessed. None of the sequences investigated required the use of intravenous contrast media. In Study I, we investigated a group of positive PE patients (verified by CTPA) alongside a volunteer group, who provided a negative PE control cohort. A b-SSFP sequence was assessed, using repetitive sampling of each slice position, in three different orthogonal planes. No triggering or breath hold techniques were used during imaging. This technique produced a large number of slices at each location for evaluation by radiologist. An excellent specificity and a good sensitivity were achieved. In Study II, a group of positive PE patients (also verified by CTPA) and a control volunteer group were used to test the DWI technique, which is not used commonly for the investigation of thrombosis in the lungs. We compared DWI against the single slice per position approach of b-SSFP and CTPA, and demonstrated its capability to depict pulmonary embolism, finding a very high sensitivity but poor specificity for DWI. In Study III, we tested two different sampling techniques for b-SSFP, Cartesian standard and golden angle radial sampling trajectories, to image the pulmonary arteries in ten volunteers and in two patients who had PE. We demonstrated the improvement of image quality when using radial trajectory sampling in comparison to the Cartesian technique. We also demonstrated that the post-reconstruction ‘sliding window’ method could be applied to the golden angle radial sampling schema when a different temporal resolution is needed. In Study IV, we used the sequence tested in Study III (b-SSFP with golden angle radial and Cartesian sampling) in a clinical setting. The study included 64 patients who were suspected of having acute PE; all were examined while waiting for CTPA diagnostic testing. We compared radial sampling versus Cartesian, and also assessed post-reconstruction images of the radial sampling, with varying temporal resolution. The radial sampling with golden angle schema did not produce images of high enough quality to depict acute PE in patients. In study V, a retrospective overview of 57 patients (2012–2018) from our institution, with suspected acute PE was made. This group of patients was contraindicated to CTPA, and so were examined only using b-SSFP images. The clinical outcome of this cohort was obtained from the electronical medical record system up to twelve months after their MRI assessments. The MRI results allowed the clinicians to change or support their decision as to which treatment strategy they chose, in patients with or without PE

Evaluation of an FDA approved library against laboratory models of human intestinal nematode infections

Treatment options for infections with soil-transmitted helminths (STH) - Ascaris lumbricoides, Trichuris trichiura and the two hookworm species, Ancylostoma duodenale and Necator americanus - are limited despite their considerable global health burden. The aim of the present study was to test the activity of an openly available FDA library against laboratory models of human intestinal nematode infections.; All 1,600 drugs were first screened against Ancylostoma ceylanicum third-stage larvae (L3). Active compounds were scrutinized and toxic compounds, drugs indicated solely for topical use, and already well-studied anthelmintics were excluded. The remaining hit compounds were tested in parallel against Trichuris muris first-stage larvae (L1), Heligmosomoides polygyrus third-stage larvae (L3), and adult stages of the three species in vitro. In vivo studies were performed in the H. polygyrus and T. muris mice models.; Fifty-four of the 1,600 compounds tested revealed an activity of > 60 % against A. ceylanicum L3 (hit rate of 3.4 %), following incubation at 200 μM for 72 h. Twelve compounds progressed into further screens. Adult A. ceylanicum were the least affected (1/12 compounds active at 50 μM), while eight of the 12 test compounds revealed activity against T. muris L1 (100 μM) and adults (50 μM), and H. polygyrus L3 (200 μM). Trichlorfon was the only compound active against all stages of A. ceylanicum, H. polygyrus and T. muris. In addition, trichlorfon achieved high worm burden reductions of 80.1 and 98.9 %, following a single oral dose of 200 mg/kg in the T. muris and H. polygyrus mouse model, respectively.; Drug screening on the larval stages of intestinal parasitic nematodes is feasible using small libraries and important given the empty drug discovery and development pipeline for STH infections. Differences and commonalities in drug activities across the different STH species and stages were confirmed. Hits identified might serve as a starting point for drug discovery for STH

Analyzing {\gamma}-rays of the Galactic Center with Deep Learning

We present a new method to interpret the $\gamma$-ray data of our inner Galaxy as measured by the Fermi Large Area Telescope (Fermi LAT). We train and test convolutional neural networks with simulated Fermi-LAT images based on models tuned to real data. We use this method to investigate the origin of an excess emission of GeV $\gamma$-rays seen in previous studies. Interpretations of this excess include $\gamma$ rays created by the annihilation of dark matter particles and $\gamma$ rays originating from a collection of unresolved point sources, such as millisecond pulsars. Our new method allows precise measurements of the contribution and properties of an unresolved population of $\gamma$-ray point sources in the interstellar diffuse emission model.Comment: 24 pages, 11 figure

Numerical modeling and characterization of high-temperature superconductor coils for electrical machines

Die aktuelle Kapazität von Hochtemperatursupraleitern (HTS) hat verschiedene Anwendungen in elektrischen Energiesystemen gefördert. Im Bereich der erneuerbaren Energien haben der weltweit steigende Energieverbrauch und die Energiewende die Forschung zu supraleitenden Generatoren für Windturbinen stark vorangetrieben, wo HTS die Leistungsdichte in Richtung besserer Multi-Megawatt-Lösungen erhöhen könnten. Trotz ihres Gleichstromwiderstands von Null können bei HTS unter zeitlich wechselndem Transportstrom oder Magnetfeld Verluste eintreten. Diese Verluste können bei den meisten HTS-Anwendungen entscheidend sein, da sie den Bedarf an Kühlleistung und den Gesamtwirkungsgrad der Maschine beeinflussen. Daher sind die Modellierung und Charakterisierung von Spulen für die weitere Entwicklung von supraleitenden Systemen von zentraler Bedeutung. Aus diesem Grund konzentriert sich diese Arbeit auf die Untersuchung von HTS-Spulen, um die technologischen Herausforderungen zukünftiger elektrischer HTS-Maschinen zu bewältigen. Da die Modellierung und Analyse von supraleitenden Spulen ein entscheidender Teil der Entwurfsphase der meisten HTS-Komponenten ist, wird ein neuer 3D-Modellierungsansatz entwickelt, der auf der Homogenisierung der T-A-Formulierung basiert. Die Modellierungsmethodik ermöglicht eine einfachere Implementierung in kommerzieller Software (COMSOL Multiphysics) im Vergleich zu der derzeit verfügbaren 3D-H-Homogenisierung. Zunächst wird der Modellierungsansatz mit 2D-Simulationen und AC-Verlustmessungen in ringförmigen Spulen validiert. Dann wird er zur Abschätzung der Verluste und zur Analyse des elektromagnetischen Verhaltens einer Racetrack-, einer Saddle- und einer Twisted-Spule verwendet. Es werden mehrere Entwürfe supraleitender Generatoren für Windturbinenanwendungen modelliert und untersucht. Besonderes Interesse gilt der Verringerung der Wechselstromverluste in der HTS-Statorwicklung, wobei drei Hauptstrategien untersucht werden: nicht planare Spulen, Reduktion der Bandbreite und Temperaturreduktion. Es wird eine neue Statorwicklungsanordnung vorgeschlagen, mit der eine 80 prozentige Reduzierung der HTS-Spulenverluste und eine bessere Verteilung der Wärmeverluste in den Spulen im Vergleich zur Standard-Racetrack-Spulenanordnung erreicht wird. Zuletzt werden zwei Racetrack-Spulen für elektrische Maschinenanwendungen hergestellt und charakterisiert. Jede Spule besteht aus 2 mm dickem Band verschiedener Hersteller, S-Innovations und Fujikura. Als erstes wird die Abhängigkeit des kritischen Stroms der Bänder von der Amplitude und Richtung des Magnetfelds gemessen. Danach werden 2D- und 3D-Modelle entwickelt, um die Induktivität, den kritischen Strom und die AC-Transportverluste in den Spulen abzuschätzen. Diese Charakterisierung wird durch experimentelle Arbeiten ergänzt, die einen direkten Vergleich von Messungen und Simulationsergebnissen ermöglichen. Der Entwurf, die Konstruktion, die Kalibrierung und der Test eines Aufbaus zur Messung der AC-Transportverluste in supraleitenden Hochtemperaturspulen auf der Grundlage eines kalorimetrischen Ansatzes (Boil-off-Methode) werden vorgestellt. Das verdampfte Kryogen (Stickstoff), das mit der Energiedissipation zusammenhängt, wird mit Hilfe eines 3D-gedruckten Blasensammlers aufgefangen, der das Gas in einen Flusssensor leitet. Ein Box-inside-a-Box-Ansatz wird verwendet, um die Messkammer mit einer kryogenen Umgebung zu umgeben. Dieser Ansatz ermöglicht die Umleitung der Wärmeübertragung aus der Umgebung in eine Zwischenzone (Raum zwischen äußerer und innerer Box). Da diese Zwischenzone unter kryogenen Temperaturen arbeitet, werden das Rauschen und die Wärmeübertragung im inneren Teil des Aufbaus reduziert. Eine statistische Analyse der Ergebnisse auf der Grundlage eines Standardlastzyklus, des Mittelwerts und der Berechnung der Standardabweichung ermöglicht es, die Variabilität der Messungen zu bewerten und die Ergebnisse als Mittelwert und Unsicherheitsbereich auszudrücken. Die Kalibrierung und Reproduzierbarkeit der Messungen werden mit einer Reihe von Widerständen unter verschiedenen Bedingungen und während verschiedener Wochen überprüft, und die Wechselstrom-Transportverluste werden gemessen und mit den Ergebnissen der 3D-Simulation verglichen

Supporting The Changing Research Practices Of Scholars Across English Literature And Modern Languages And Literatures At Swarthmore College

In collaboration with ITHAKA S+R, and the Modern Language Association of America (MLA), Swarthmore College Libraries examined the research practices of scholars in the departments of English Literature and Modern Languages and Literatures spring 2019. This project includes research teams from 14 academic libraries with the intention to identify services to better support scholars. Swarthmore, together with Haverford College, worked at critical junctures in the project to maximize insight as the only liberal arts colleges participating in the larger study. ITHAKA S+R is a non-profit organization that helps “academic and cultural communities know what is coming next, learn from rigorous and well-designed research studies, and adapt to new realities and opportunities.” The MLA is a non-profit that “ promotes the study and teaching of languages and literatures through its programs, publications, annual convention, and advocacy work.” The Swarthmore College research team was comprised of Pamela Harris, Associate College Librarian for Research and Information and Roberto Vargas, Research Librarian for Humanities and Interdisciplinary Studies

3D Homogenized T-A Formulation for Modeling HTS Coils

The estimation of losses in high-temperature superconductors (HTS) is fundamental during the design of superconducting devices since losses can strongly influence the cooling system requirements and operating temperature. Typically, 2D finite element analysis is used to calculate AC losses in HTS, due to the lack of analytical solutions that can accurately represent complex operating conditions such as AC transport current and AC external applied magnetic field in coils. These 2D models are usually a representation of an infinitely long arrangement. Therefore, they cannot be used to analyze end effects and complex 3D configurations. In this publication, we use the T-A homogenization in 3D for the analysis of superconducting coils. This allows simulating complex geometries such as racetrack coils. We show that this approach has lower computation time than the currently available 3D homogenization of the H formulation. The approach is first validated against measurements and 2D axisymmetric solutions. Then, it is used to estimate losses and study the electromagnetic behavior of a racetrack coil

The Impact of Obesity and Adipokines on Breast and Gynecologic Malignancies

The link between obesity and multiple disease comorbidities is well established. In 2003, Calle and colleagues presented the relationship between obesity and several cancer types, including breast, ovarian, and endometrial malignancies. Nearly, 20% of cancer-related deaths in females can be accounted for by obesity. Identifying obesity as a risk factor for cancer led to a focus on the role of fat-secreted cytokines, known as adipokines, on carcinogenesis and tumor progression. Early studies indicated that the adipokine leptin increases cell proliferation, invasion, and inhibition of apoptosis in multiple cancer types. As a greater appreciation of the obesity–cancer link has amassed, we now know that additional adipokines can impact tumorigenesis. A deeper understanding of the adipokine-activated signaling in cancer may identify new treatment strategies irrespective of obesity. Moreover, adipokines may serve as disease biomarkers, harnessing the potential of obesity-associated factors to serve as indicators of treatment response and disease prognosis. As studies investigating obesity and women\u27s cancers continue to expand, it has become evident that breast, ovarian, and uterine cancers are distinctly impacted by adipokines. While complex, these distinct interactions may provide insight into cancer progression in these organs and new opportunities for targeted therapies. This review aims to organize and present the literature from the last 5 years investigating the mechanisms and implications of adipokine signaling in breast, endometrial, and ovarian cancers with a special focus on leptin and adiponectin