81 research outputs found

    Brownian motion of solitons in a Bose-Einstein Condensate

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    We observed and controlled the Brownian motion of solitons. We launched solitonic excitations in highly elongated 87 Rb Bose-Einstein condensates (BECs) and showed that a dilute background of impurity atoms in a different internal state dramatically affects the soliton. With no impurities and in one-dimension (1D), these solitons would have an infinite lifetime, a consequence of integrability. In our experiment, the added impurities scatter off the much larger soliton, contributing to its Brownian motion and decreasing its lifetime. We describe the soliton\u27s diffusive behavior using a quasi-1D scattering theory of impurity atoms interacting with a soliton, giving diffusion coefficients consistent with experiment

    Byproduct Valorization : From Spent Coffee Grounds to Fatty Acid Ethyl Esters

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    A laboratory experiment was designed to provide students with an introduction to byproduct valorization by producing an analogue of biodiesel (fatty acid ethyl esters, FAEE) via lipid extraction and subsequent transesterification from spent coffee grounds (SCG). Valorization is the process of upgrading underutilized or discarded wastes or byproducts into chemicals, materials, and (bio)energy. Upon isolation of the intermediate and FAEE, students analyzed the respective spectroscopic characteristics using infrared and nuclear magnetic resonance spectroscopy as well as evaluated gas chromatography spectra that were provided. Associated green metrics for the reaction were determined to obtain a quantitative measure of the “greenness” of the experiment. In this laboratory experiment, students are introduced to key concepts such as whole systems thinking and the United Nations Sustainable Development Goals where they apply these frameworks to real-world problems such as consumption and waste disposal. In addition to providing a greener alternative to traditional methods for biodiesel analogue production from SCG by solvent alterations, this experiment demonstrates the value of waste that would otherwise be overlooked to generate products that can help reduce the continued use of finite fossil fuels

    Intracranial Vertebrobasilar Artery Dissection Associated with Postpartum Angiopathy

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    Background. Cervicocephalic arterial dissection (CCAD) is rare in the postpartum period. To our knowledge this is the first reported case of postpartum angiopathy (PPA) presenting with ischemic stroke due to intracranial arterial dissection. Case. A 41-year-old woman presented with blurred vision, headache, and generalized seizures 5 days after delivering twins. She was treated with magnesium for eclampsia. MRI identified multiple posterior circulation infarcts. Angiography identified a complex dissection extending from both intradural vertebral arteries, through the basilar artery, and into both posterior cerebral arteries. Multiple segments of arterial dilatation and narrowing consistent with PPA were present. Xenon enhanced CT (Xe-CT) showed reduced regional cerebral blood flow that is improved with elevation in blood pressure. Conclusion. Intracranial vertebrobasilar dissection causing stroke is a rare complication of pregnancy. Eclampsia and PPA may play a role in its pathogenesis. Blood pressure management may be tailored using quantitative blood flow studies, such as Xe-CT

    The urine biomarker PUR-4 is positively associated with the amount of Gleason 4 in human prostate cancers

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    The Prostate Urine Risk (PUR) biomarker is a four-group classifier for predicting outcome in patients prior to biopsy and for men on active surveillance. The four categories correspond to the probabilities of the presence of normal tissue (PUR-1), D’Amico low-risk (PUR-2), intermediate-risk (PUR-3), and high-risk (PUR-4) prostate cancer. In the current study we investigate how the PUR-4 status is linked to Gleason grade, prostate volume, and tumor volume as assessed from biopsy (n = 215) and prostatectomy (n = 9) samples. For biopsy data PUR-4 status alone was linked to Gleason Grade group (GG) (Spearman’s, ρ = 0.58, p < 0.001 trend). To assess the impact of tumor volume each GG was dichotomized into Small and Large volume cancers relative to median volume. For GG1 (Gleason Pattern 3 + 3) cancers volume had no impact on PUR-4 status. In contrast for GG2 (3 + 4) and GG3 (4 + 3) cancers PUR-4 levels increased in large volume cancers with statistical significance observed for GG2 (p = 0.005; Games-Howell). These data indicated that PUR-4 status is linked to the presence of Gleason Pattern 4. To test this observation tumor burden and Gleason Pattern were assessed in nine surgically removed and sectioned prostates allowing reconstruction of 3D maps. PUR-4 was not correlated with Gleason Pattern 3 amount, total tumor volume or prostate size. A strong correlation was observed between amount of Gleason Pattern 4 tumor and PUR-4 signature (r = 0.71, p = 0.034, Pearson’s). These observations shed light on the biological significance of the PUR biomarker and support its use as a non-invasive means of assessing the presence of clinically significant prostate cancer

    Establishment of wMel Wolbachia in Aedes aegypti mosquitoes and reduction of local dengue transmission in Cairns and surrounding locations in northern Queensland, Australia.

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    Background: The wMel strain of Wolbachia has been successfully introduced into Aedes aegypti mosquitoes and subsequently shown in laboratory studies to reduce transmission of a range of viruses including dengue, Zika, chikungunya, yellow fever, and Mayaro viruses that cause human disease. Here we report the entomological and epidemiological outcomes of staged deployment of Wolbachia across nearly all significant dengue transmission risk areas in Australia. Methods: The  wMel strain of  Wolbachia was backcrossed into the local  Aedes aegypti genotype (Cairns and Townsville backgrounds) and mosquitoes were released in the field by staff or via community assisted methods. Mosquito monitoring was undertaken and mosquitoes were screened for the presence of  Wolbachia. Dengue case notifications were used to track dengue incidence in each location before and after releases. Results: Empirical analyses of the Wolbachia mosquito releases, including data on the density, frequency and duration of Wolbachia mosquito releases, indicate that Wolbachia can be readily established in local mosquito populations, using a variety of deployment options and over short release durations (mean release period 11 weeks, range 2-22 weeks). Importantly, Wolbachia frequencies have remained stable in mosquito populations since releases for up to 8 years. Analysis of dengue case notifications data demonstrates near-elimination of local dengue transmission for the past five years in locations where Wolbachia has been established. The regression model estimate of Wolbachia intervention effect from interrupted time series analyses of case notifications data prior to and after releases, indicated a 96% reduction in dengue incidence in Wolbachia treated populations (95% confidence interval: 84 - 99%). Conclusion: Deployment of the wMel strain of Wolbachia into local Ae. aegypti populations across the Australian regional cities of Cairns and most smaller regional communities with a past history of dengue has resulted in the reduction of local dengue transmission across all deployment areas

    The SRG Rat, a Sprague-Dawley Rag2/Il2rg Double-Knockout Validated for Human Tumor Oncology Studies

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    We have created the immunodeficient SRG rat, a Sprague-Dawley Rag2/Il2rg double knockout that lacks mature B cells, T cells, and circulating NK cells. This model has been tested and validated for use in oncology (SRG OncoRat®). The SRG rat demonstrates efficient tumor take rates and growth kinetics with different human cancer cell lines and PDXs. Although multiple immunodeficient rodent strains are available, some important human cancer cell lines exhibit poor tumor growth and high variability in those models. The VCaP prostate cancer model is one such cell line that engrafts unreliably and grows irregularly in existing models but displays over 90% engraftment rate in the SRG rat with uniform growth kinetics. Since rats can support much larger tumors than mice, the SRG rat is an attractive host for PDX establishment. Surgically resected NSCLC tissue from nine patients were implanted in SRG rats, seven of which engrafted and grew for an overall success rate of 78%. These developed into a large tumor volume, over 20,000 mm3 in the first passage, which would provide an ample source of tissue for characterization and/or subsequent passage into NSG mice for drug efficacy studies. Molecular characterization and histological analyses were performed for three PDX lines and showed high concordance between passages 1, 2 and 3 (P1, P2, P3), and the original patient sample. Our data suggest the SRG OncoRat is a valuable tool for establishing PDX banks and thus serves as an alternative to current PDX mouse models hindered by low engraftment rates, slow tumor growth kinetics, and multiple passages to develop adequate tissue banks

    Weather and our food supply

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    The steep rate of increase in yield of grain crops in the United States since the mid-1950\u27s has resulted in the use of the term explosion in technology. Surplus grains piled up to such proportions after the 1960 · harvest that acreage control appeared. to be in order. But despite substantial reductions in acreages after 1960 the increased output per acre has just about compensated for acreage reductions. During this period of rapid increase in output per acre there has been a growing tendency to believe that technology has reduced the influence of weather on grain production so that we no longer need to fear shortages due to unfavorable weather. There is also a popular belief that acreage control$ fail to achieve the objective of production control, and that public funds are being wasted in storing surplus grains which we don\u27t need. There is increasing evidence, however, that a period of favorable weather interacted with technology to produce our recent high yields, and that perhaps half of the increase in yield per acre since 1950 has been due to a change to more favorable weather for grain crops. These findings have important implications in continued support for research in production technology and in the way in which we look at our surplus stocks of feed and food grains. If a period of favorable weather has been responsible for half of the increase in yields since 19501 then what can we expect if the weather trend reverses itself for a few years? Do we have periodicity in weather, and have we just passed through a run of favorable years that might be followed by a run of unfavorable years? Should we treat our surplus grains as reserves? How does our rate of growth in grain output compare with the needs of a growing world population? And of course I in the background of these questions is one big question -- how much of our recent high yields is really due to weather? To answer these important questions the Center for Agriculture and Economic Development invited outstanding authorities to present their ideas under three main headings: (1) Techniques for Evaluation of Weather Variables in Agricultural Production I (2) Periodicity in Weather Patterns: Implications in Agriculture I and (3) Weather Considerations in Agricultural Policy. The papers have been assembled in the order of their presentation under the general outline above.https://lib.dr.iastate.edu/card_reports/1021/thumbnail.jp

    Rockport Comprehensive Plan

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    This document was developed and prepared by Texas Target Communities (TxTC) at Texas A&M University in partnership with the City of Rockport, Texas Sea Grant, Texas A&M University - Corpus Christi, Texas A&M University - School of Law and Texas Tech University.Founded in 1871, the City of Rockport aims to continue growing economically and sustainably. Rockport is a resilient community dedicated to sustainable growth and attracting businesses to the area. Rockport is a charming town that offers a close-knit community feel and is a popular tourist destination for marine recreation, fairs, and exhibitions throughout the year. The Comprehensive Plan 2020-2040 is designed to guide the city of Rockport for its future growth. The guiding principles for this planning process were Rockport's vision statement and its corresponding goals, which were crafted by the task force. The goals focus on factors of growth and development including public participation, development considerations, transportation, community facilities, economic development, parks, and housing and social vulnerability

    Physiological Concentrations of Amyloid Beta Regulate Recycling of Synaptic Vesicles via Alpha7 Acetylcholine Receptor and CDK5/Calcineurin Signaling

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    Despite the central role of amyloid β (Aβ) peptide in the etiopathogenesis of Alzheimer’s disease (AD), its physiological function in healthy brain is still debated. It is well established that elevated levels of Aβ induce synaptic depression and dismantling, connected with neurotoxicity and neuronal loss. Growing evidence suggests a positive regulatory effect of Aβ on synaptic function and cognition; however the exact cellular and molecular correlates are still unclear. In this work, we tested the effect of physiological concentrations of Aβ species of endogenous origin on neurotransmitter release in rat cortical and hippocampal neurons grown in dissociated cultures. Modulation of production and degradation of the endogenous Aβ species as well as applications of the synthetic rodent Aβ40 and Aβ42 affected efficacy of neurotransmitter release from individual presynapses. Low picomolar Aβ40 and Aβ42 increased, while Aβ depletion or application of low micromolar concentration decreased synaptic vesicle recycling, showing a hormetic effect of Aβ on neurotransmitter release. These Aβ-mediated modulations required functional alpha7 acetylcholine receptors as well as extracellular and intracellular calcium, involved regulation of CDK5 and calcineurin signaling and increased recycling of synaptic vesicles. These data indicate that Aβ regulates neurotransmitter release from presynapse and suggest that failure of the normal physiological function of Aβ in the fine-tuning of SV cycling could disrupt synaptic function and homeostasis, which would, eventually, lead to cognitive decline and neurodegeneration
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