3,534 research outputs found

    Coastal Research Imaging Spectrometer

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    The Coastal Research Imaging Spectrometer (CRIS) is an airborne remote sensing system designed specifically for research on the physical, chemical, and biological characteristics of coastal waters. The CRIS includes a visible-light hyperspectral imaging subsystem for measuring the color of water, which contains information on the biota, sediment, and nutrient contents of the water. The CRIS also includes an infrared imaging subsystem, which provides information on the temperature of the water. The combination of measurements enables investigation of biological effects of both natural and artificial flows of water from land into the ocean, including diffuse and point-source flows that may contain biological and/or chemical pollutants. Temperature is an important element of such measurements because temperature contrasts can often be used to distinguish among flows from different sources: for example, a sewage outflow could manifest itself in spectral images as a local high-temperature anomaly. Both the visible and infrared subsystems scan in pushbroom mode: that is, an aircraft carrying the system moves along a ground track, the system is aimed downward, and image data are acquired in across-track linear arrays of pixels. Both subsystems operate at a frame rate of 30 Hz. The infrared and visible-light optics are adjusted so that both subsystems are aimed at the same moving swath, which has across-track angular width of 15 . Data from the infrared and visible imaging subsystems are stored in the same file along with aircraft- position data acquired by a Global Positioning System receiver. The combination of the three sets of data is used to construct infrared and hyperspectral maps of scanned areas (see figure). The visible subsystem is based on a grating spectrograph and a rapid-readout charge-coupled-device camera. Images of the swatch are acquired in 256 spectral bands at wavelengths from 400 to 800 nm. The infrared subsystem, which is sensitive in a single wavelength band of 8 to 10 m, is based on a focal-plane array of HgCdTe photodetectors that are cooled to an operating temperature of 77 K by use of a closed-Stirling-cycle mechanical cooler. The nonuniformities of the HgCdTe photodetector array are small enough that the raw pixel data from the infrared subsystem can be used to recognize temperature differences on the order of 1 C. By use of a built-in blackbody calibration source that can be switched into the field of view, one can obtain bias and gain offset terms for individual pixels, making it possible to offset the effects of nonuniformities sufficiently to enable the measurement of temperature differences as small as 0.1 C

    Chlamydia pneumoniae infection of neuronal cells induces changes in calcium-associated gene expression consistent with Alzheimer’s disease

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    Background and Significance: Previous studies have shown that cells infected with Chlamydia pneumoniae (Cpn) exhibit altered gene expression consistent with that observed in Alzheimer’s disease (AD). Furthermore, AD neurodegeneration has been linked to dysregulation of intracellular calcium and calcium-related processes. Therefore, we hypothesize that one mechanism by which pathogenesis evolves in AD is through infection-induced changes in expression of calcium-related genes. Objectives: To determine if infection of neuronal cells with Cpn alters expression of calciumrelated genes associated with neurodegeneration. Methods: SK-N-MC neuronal cells were infected with Cpn (AR39 strain; MOI=1) for 3 to 72 hours, then calcium-related genes were screened with real-time PCR microarrays (SABiosciences PAHS-066). Results: Following infection, approximately 29 genes displayed regulation changes of 2-fold or greater, including genes pertaining to neurotransmitters, cell cycle and immune regulators, and other calcium-responsive elements. Genes involved in synaptic function and memory such as AREG, ATF3, EGR2 and GEM were initially up regulated, then fell to baseline or below by 72 hours. Many of the affected genes have been implicated in AD pathogenesis. Conclusions: Our data suggest that Cpn alters calcium-related gene expression in host neurons consistent with calcium dysfunction previously documented in AD. This study may elucidate how, in its effort to establish a favorable environment, Cpn could affect cellular processes that contribute to AD pathogenesis.https://digitalcommons.pcom.edu/posters/1006/thumbnail.jp

    Infection with Chlamydia Pneumoniae Alters Calcium-associated Gene Regulation and Processes in Neuronal Cells and Monocytes: Implications for Alzheimer’s Disease

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    Background: First proposed by Khachaturian in 1994, the calcium hypothesis postulates that sustained disturbance of intracellular calcium is the leading cause of neurodegenerative disorders. Studies showing alteration in calcium signaling in both sporadic and familial Alzheimer’s disease (AD) support this hypothesis. Intracellular calcium signaling is tightly regulated in time, intensity, and space, and is responsible for a variety of neuronal functions. Calcium influx from the extracellular environment modulates calcium levels, as do intracellular stores in the endoplasmic reticulum. The focus of this study was to test various calcium related genes in both monocytes and neuronal cells. Previous studies have shown that cells infected with Chlamydia pneumoniae (Cpn) exhibit altered protein processing, such as amyloid and tau modification, consistent with those found in AD. We expect to see significant alterations in calcium genes, as well as their protein products in Cpn infected cells. Every calcium gene has a unique function in the cell. Determining which genes are up or down regulated following infection may provide insight into how the neurodegeneration process observed in AD is initiated by Cpn infections

    Depolarization of sperm membrane potential is a common feature of men with subfertility and is associated with low fertilization rate at IVF

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    STUDY QUESTION. Are significant abnormalities in outward (K+) conductance and resting membrane potential (Vm) present in the spermatozoa of patients undertaking IVF and ICSI and if so, what is their functional effect on fertilization success? SUMMARY ANSWER. Negligible outward conductance (≈5% of patients) or an enhanced inward conductance (≈4% of patients), both of which caused depolarization of Vm, were associated with a low rate of fertilization following IVF. WHAT IS KNOWN ALREADY. Sperm-specific potassium channel knockout mice are infertile with defects in sperm function, suggesting that these channels are essential for fertility. These observations suggest that malfunction of K+ channels in human spermatozoa might contribute significantly to the occurrence of subfertility in men. However, remarkably little is known of the nature of K+ channels in human spermatozoa or the incidence and functional consequences of K+ channel defects. STUDY DESIGN, SIZE AND DURATION. Spermatozoa were obtained from healthy volunteer research donors and subfertile IVF and ICSI patients attending a hospital assisted reproductive techniques clinic between May 2013 and December 2015. In total, 40 IVF patients, 41 ICSI patients and 26 normozoospermic donors took part in the study. PARTICIPANTS/MATERIALS, SETTING, METHODS. Samples were examined using electrophysiology (whole-cell patch clamping). Where abnormal electrophysiological characteristics were identified, spermatozoa were further examined for Ca2+ influx induced by progesterone and penetration into viscous media if sufficient sample was available. Full exome sequencing was performed to specifically evaluate potassium calcium-activated channel subfamily M α 1 (KCNMA1), potassium calcium-activated channel subfamily U member 1 (KCNU1) and leucine-rich repeat containing 52 (LRRC52) genes and others associated with K+ signalling. In IVF patients, comparison with fertilization rates was done to assess the functional significance of the electrophysiological abnormalities. MAIN RESULTS AND THE ROLE OF CHANCE. Patch clamp electrophysiology was used to assess outward (K+) conductance and resting membrane potential (Vm) and signalling/motility assays were used to assess functional characteristics of sperm from IVF and ICSI patient samples. The mean Vm and outward membrane conductance in sperm from IVF and ICSI patients were not significantly different from those of control (donor) sperm prepared under the same conditions, but variation between individuals was significantly greater (P< 0.02) with a large number of outliers (>25%). In particular, in ≈10% of patients (7/81), we observed either a negligible outward conductance (4 patients) or an enhanced inward current (3 patients), both of which caused depolarization of Vm. Analysis of clinical data from the IVF patients showed significant association of depolarized Vm (≥0 mV) with low fertilization rate (P= 0.012). Spermatozoa with electrophysiological abnormities (conductance and Vm) responded normally to progesterone with elevation of [Ca2+]i and penetration of viscous medium, indicating retention of cation channel of sperm (CatSper) channel function. LIMITATIONS, REASONS FOR CAUTION. For practical, technical, ethical and logistical reasons, we could not obtain sufficient additional semen samples from men with conductance abnormalities to establish the cause of the conductance defects. Full exome sequencing was only available in two men with conductance defects. WIDER IMPLICATIONS OF THE FINDINGS. These data add significantly to the understanding of the role of ion channels in human sperm function and its impact on male fertility. Impaired potassium channel conductance (Gm) and/or Vm regulation is both common and complex in human spermatozoa and importantly is associated with impaired fertilization capacity when the Vm of cells is completely depolarized

    Effect of Atomoxetine Treatment on Reading and Phonological Skills in Children with Dyslexia or Attention-Deficit/Hyperactivity Disorder and Comorbid Dyslexia in a Randomized, Placebo-Controlled Trial

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    OBJECTIVES: Evaluated the effects of atomoxetine on the reading abilities of children with dyslexia only or attention-deficit/hyperactivity disorder (ADHD) and comorbid dyslexia. METHODS: Children aged 10-16 years (N = 209) met Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM-IV-TR) criteria for dyslexia only (n = 58), ADHD and comorbid dyslexia (n = 124), or ADHD only (n = 27) and were of normal intelligence. Patients were treated with atomoxetine (1.0-1.4 mg/kg/day) or placebo in a 16-week, randomized, placebo-controlled, double-blind trial. The dyslexia-only and ADHD and comorbid dyslexia groups were randomized 1:1; the ADHD-only group received atomoxetine in a blinded manner. Reading abilities were measured with the Woodcock Johnson III (WJIII), Comprehensive Test of Phonological Processing (CTOPP), Gray Oral Reading Tests-4, and Test of Word Reading Efficiency. RESULTS: Atomoxetine-treated dyslexia-only patients compared with placebo patients had significantly greater improvement (p < 0.02) with moderate to approaching high effect sizes (ES) on WJIII Word Attack (ES = 0.72), Basic Reading Skills (ES = 0.48), and Reading Vocabulary (ES = 0.73). In the atomoxetine-treated ADHD and comorbid dyslexia group, improvement on the CTOPP Elision measure (ES = 0.50) was significantly greater compared with placebo (p < 0.02). Total, inattentive, and hyperactive/impulsive ADHD symptom reductions were significant in the atomoxetine-treated ADHD and comorbid dyslexia group compared with placebo, and from baseline in the ADHD-only group (p ≤ 0.02). ADHD symptom improvements in the ADHD and comorbid dyslexia group were not correlated with improvements in reading. CONCLUSIONS: Atomoxetine treatment improved reading scores in patients with dyslexia only and ADHD and comorbid dyslexia. Improvements for patients with dyslexia only were in critical components of reading, including decoding and reading vocabulary. For patients with ADHD and comorbid dyslexia, improvements in reading scores were distinct from improvement in ADHD inattention symptoms alone. These data represent the first report of improvements in reading measures following pharmacotherapy treatment in patients with dyslexia only evaluated in a randomized, double-blind trial

    Ultrashort Laser Pulse Interactions With Matter - New Effects and Spectroscopic Applications

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    Contains research summary and reports on four research projects.Joint Services Electronics Program (Contract DAAL03-86-K-0002)Joint Services Electronics Program (Contract DAALO3-89-C-0001

    Alpha-Cyclodextrin-Containing Beverages for Hydration Enhancement in Humans

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    A substantial portion of the world’s population may be inadequately hydrated, and dehydration is associated with several disease states and acute impairments in exercise performance. As such, there is continued interest in novel strategies to promote adequate hydration. The carbohydrate alpha-cyclodextrin has recently been shown to enhance water uptake through human aquaporins expressed in a single-cell model and promote longevity in model multicellular organisms. However, there is no relevant human research examining the potential hydrating effects of alpha-cyclodextrin-containing beverages. PURPOSE: To determine if novel beverage formulations containing alpha-cyclodextrin improve a bioimpedance-based hydration marker in humans. METHODS: In a randomized, double-blind, crossover design, eight adults (5 M, 3 F; [mean ± SD] age: 24.9 ± 4.2 years; height: 169.6 ± 5.5 cm; weight: 71.2 ± 13.2 kg; body mass index: 24.6 ± 3.2 kg/m2; body fat: 17.0 ± 5.6%) completed trials including the ingestion of 1 liter of still water (control; CON), still water plus alpha-cyclodextrin (CD), or still water plus alpha- cyclodextrin and complexing agents (B-vitamins and amino acids; Complex). Before beverage ingestion, and every 15 minutes for two hours following beverage ingestion, bioimpedance spectroscopy was performed to estimate phase angle values as a noninvasive marker of cellular hydration. Phase angle was calculated as: arctan(/) × (180°/), where Xc is the reactance (indicative of the capacitive properties of the cell membrane) and R is resistance (opposition to flow of electrical current), both obtained from bioimpedance spectroscopy. Due to the pilot nature of this trial, data were analyzed using descriptive statistics only (data presented as median ± interquartile range). RESULTS: Two hours after completion of beverage ingestion, median ± interquartile range changes in phase in angle were 3.4 ± 1.7% for CON, 4.6 ± 1.2% for CD, and 5.4 ± 3.3% for Complex. Xc changes were 9.9 ± 2.9% for CON, 10.9 ± 3.0% for CD, and 11.1 ± 3.1% for Complex. R changes were 6.5 ± 1.4% for CON, 6.8 ± 1.9% for CD, and 5.6 ± 1.1% for Complex. CONCLUSION: The results of this pilot study indicate the potential for alpha-cyclodextrin- containing beverages to improve a bioimpedance-based hydration marker, phase angle, in humans, with the potential that B-vitamins and amino acids may further enhance hydration beyond alpha-cyclodextrin alone. The larger improvements in phase angle in the Complex group were due to a greater increase in bioelectrical reactance alongside a smaller increase in bioelectrical resistance. Future research with larger sample sizes should examine the potential for these beverages to improve human hydration and health

    NLO Higgs boson production plus one and two jets using the POWHEG BOX, MadGraph4 and MCFM

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    We present a next-to-leading order calculation of Higgs boson production plus one and two jets via gluon fusion interfaced to shower Monte Carlo programs, implemented according to the POWHEG method. For this implementation we have used a new interface of the POWHEG BOX with MadGraph4, that generates the codes for generic Born and real processes automatically. The virtual corrections have been taken from the MCFM code. We carry out a simple phenomenological study of our generators, comparing them among each other and with fixed next-to-leading order results.Comment: 27 pages, 21 figure

    Cohort Profile: The Study of Respiratory Pathogens in Andean Children

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    We investigated respiratory pathogens in a prospective cohort study of young children living in the Peruvian Andes. In the study we assessed viral respiratory infections among young children, and explored interactions of viruses with common respiratory bacteria, especially Streptococcus pneumoniae. Through weekly household visits, data were collected on the signs and symptoms of acute respiratory illness (ARI), nasal samples were collected to test for viruses during episodes of ARI, and nasopharyngeal samples were collected on a monthly basis to monitor bacterial colonisation. We also collected data on vaccination coverage, patterns of social mixing, geographic information, and environmental and socio-demographic variables. Understanding the interaction of respiratory viruses with bacteria and its impact on the burden and severity of ARIs in rural areas of developing countries is critical to designing strategies for preventing such infections. Investigators interested in more details about this study or in accessing these resources should contact Dr. Carlos G. Grijalva at Vanderbilt University ([email protected]
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