760 research outputs found

    Nanoscale magnetic field mapping with a single spin scanning probe magnetometer

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    We demonstrate quantitative magnetic field mapping with nanoscale resolution, by applying a lock-in technique on the electron spin resonance frequency of a single nitrogen-vacancy defect placed at the apex of an atomic force microscope tip. In addition, we report an all-optical magnetic imaging technique which is sensitive to large off-axis magnetic fields, thus extending the operation range of diamond-based magnetometry. Both techniques are illustrated by using a magnetic hard disk as a test sample. Owing to the non-perturbing and quantitative nature of the magnetic probe, this work should open up numerous perspectives in nanomagnetism and spintronics

    Economic benefits of metrology in manufacturing

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    In streamlined manufacturing systems, the added value of inspection activities is often questioned, and metrology in particular is sometimes considered only as an avoidable expense. Documented quantification of economic benefits of metrology is generally not available. This work presents concrete examples from industrial production, in which the added value of metrology in manufacturing is discussed and quantified. Case studies include: general manufacturing, forging, machining, and related metrology. The focus of the paper is on the improved effectiveness of metrology when used at product and process design stages, as well as on the improved accuracy and efficiency of manufacturing through better measuring equipment and process chains with integrated metrology for process control

    Geometrical Product Specification and Verification as toolbox to meet up-to-date technical requirements

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    The ISO standards for the Geometrical Product Specification and Verification (GPS) define an internationally uniform description language, that allows expressing unambiguously and completely all requirements for the geometry of a product with the corresponding requirements for the inspection process in technical drawings, taking into account current possibilities of measurement and testing technology. The practice shows that the university curricula of the mechanical engineering faculties often include only limited classes on the GPS, mostly as part of curriculum of subjects like Metrology or Fundamentals of Machine Design. This does not allow students to gain enough knowledge on the subject. Currently there is no coherent EU-wide provision for vocational training (VET) in this area. Consortium, members of which are the authors of this paper, is preparing a proposal of an EU project aiming to develop appropriate course

    Cortical Circuitry Associated With Reflex Cardiovascular Control in Humans: Does the Cortical Autonomic Network Speak or Listen During Cardiovascular Arousal

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    Beginning with clinical evidence of fatal cardiac arrhythmias in response to severe stress, in epileptic patients, and following stroke, the role of the cerebral cortex in autonomic control of the cardiovascular system has gained both academic and clinical interest. Studies in anesthetized rodents have exposed the role of several forebrain regions involved in cardiovascular control. The introduction of functional neuroimaging techniques has enabled investigations into the conscious human brain to illuminate the temporal and spatial activation patterns of cortical regions that are involved with cardiovascular control through the autonomic nervous system. This symposia report emphasizes the research performed by the authors to understand the functional organization of the human forebrain in cardiovascular control during physical stressors of baroreceptor unloading and handgrip exercise. The studies have exposed important associations between activation patterns of the insula cortex, dorsal anterior cingulate, and the medial prefrontal cortex and cardiovascular adjustments to physical stressors. Furthermore, these studies provide functional anatomic evidence that sensory signals arising from baroreceptors and skeletal muscle are represented within the insula cortex and the medial prefrontal cortex, in addition to the sensory cortex. Thus, the cortical pathways subserving reflex cardiovascular control integrate viscerosensory inputs with outgoing traffic that modulates the autonomic nervous system. © 2012 Wiley Periodicals, Inc.

    Assessing the genetic diversity of rice originating from Bangladesh, Assam and West Bengal

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    Acknowledgements This work was funded by BBSRC research project BB/J00336/1. FS and a part of the proportion of the cost of the Illumina genotyping was funded by a Beachell-Borlag International Fellowship. The authors would like to acknowledge the help of Dr MK Sarmah in collecting seed samples of the landraces and improved cultivars from Assam used in this study and Dr. Ma. Elizabeth B. Naredo and Ms. Sheila Mae Q. Mercado for handling of IRGC accessions and preparation of DNAs for genotyping. All rice seeds used here were obtained with MTA agreements and seed and dry leaves imported into the UK under import licence IMP⁄SOIL⁄18⁄2009 issued by Science and Advice for Scottish Agriculture.Peer reviewedPublisher PD

    Assessment of the impact of race and proxies of socioeconomic status on the prevalence and health outcome of peripartum cardiomyopathy (PPCM) using the “All of Us” Databank

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    Background: Peripartum Cardiomyopathy (PPCM) is a form of cardiomyopathy occurring during the last month of pregnancy or within months after giving birth in women with previously normal hearts. PPCM is an idiopathic systolic dysfunction that causes a reduced left ventricle ejection fraction. The estimated incidence of PPCM worldwide is 1 diagnosis out of 2,000 live births, and the causes of PPCM remain unknown. A retrospective cohort study conducted at the University of Pennsylvania Health System by Getz et al. showed that black race and socioeconomic proxies (like neighborhood disadvantage index (NDI)) were independently associated with sustained cardiac dysfunction (Getz et al., Am Heart J 2021). This study also showed that from all the components of NDI (education, high rental occupied housing, annual income below poverty line, female headed household, adults unemployed, adults on public assistance), low education and high rental occupied housing were significantly associated with sustained cardiac dysfunction. The central aim of the present project is to assess the effect of socioeconomic proxies (including NDI, lack of access to health care and food insecurity) on the prevalence of sustained cardiac dysfunction from PPCM across the US using the “All of Us” databank. A secondary aim is to test the compliance of the All of Us database capacity to interrogate this potential association. Lastly, we aim to compare the results obtained from the All of Us database with the UK Biobank. Methods: The All of Us databank (Ramirez et al., Patterns 2022; The All of US Research Program, NEJM 2019) will be used to conduct a retrospective cohort study to assess how proxies of socioeconomic status may affect the incidence and prevalence of sustained cardiac dysfunction from PPCM across different ethnicities in the US. The All of Us database focuses on enrolling people in the US from diverse groups that have historically been underrepresented in medical research. Therefore, it includes a more diverse population than the population targeted in the retrospective study conducted at the University of Pennsylvania in which only black women from Philadelphia, PA, were included. To further interrogate the impact that geographic location and population ethnicity may have on the prevalence of sustained cardiac dysfunction from PPCM, the results obtained from the “All of Us” database will be compared against data obtained from the UK Biobank. Expected Results: We expect that the socioeconomic proxies interrogated in this study will have a significant impact on the prevalence of sustained cardiac dysfunction from PPCM. Current knowledge is limited on how socioeconomic status affects sustained cardiac dysfunction resulting from PPCM. Previous studies have been done on populations restricted to small geographic areas and did not analyze factors such as food security, access to care, or disability status. Understanding how these factors affect the incidence and prevalence of sustained cardiac dysfunction from PPCM may be used to improve prevention, early diagnosis, and management of PPCM

    Mutant huntingtin enhances activation of dendritic Kv4 K+ channels in striatal spiny projection neurons

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    Huntington\u27s disease (HD) is initially characterized by an inability to suppress unwanted movements, a deficit attributable to impaired synaptic activation of striatal indirect pathway spiny projection neurons (iSPNs). To better understand the mechanisms underlying this deficit, striatal neurons in ex vivo brain slices from mouse genetic models of HD were studied using electrophysiological, optical and biochemical approaches. Distal dendrites of iSPNs from symptomatic HD mice were hypoexcitable, a change that was attributable to increased association of dendritic Kv4 potassium channels with auxiliary KChIP subunits. This association was negatively modulated by TrkB receptor signaling. Dendritic excitability of HD iSPNs was rescued by knocking-down expression of Kv4 channels, by disrupting KChIP binding, by restoring TrkB receptor signaling or by lowering mutant-Htt (mHtt) levels with a zinc finger protein. Collectively, these studies demonstrate that mHtt induces reversible alterations in the dendritic excitability of iSPNs that could contribute to the motor symptoms of HD

    Instrumentation Design and Placement for KRUPS Re-Entry Capsules

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    Atmospheric re-entry flight tests are one of the best ways to evaluate the performance of new Thermal Protection System (TPS) materials. The flight proven Kentucky Re-Entry Payload System (KRUPS) project provides a low cost, quick turnaround platform for these evaluative missions. Following the success of the first KREPE mission, the Krups Flight Computer (KFC) and the instrumentation suite were redesigned for the next mission, KREPE-2. The original suite contained only four thermocouoples. The new design contains six thermocouples, five pressure sensors, a mini-spectrometer, an IMU and an accelerometer
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