keyword
MENU ▼
Read by QxMD icon Read
search

Chris Powers

keyword
https://www.readbyqxmd.com/read/29048396/time-multiplexed-active-neural-probe-with-1356-parallel-recording-sites
#1
Bogdan C Raducanu, Refet F Yazicioglu, Carolina M Lopez, Marco Ballini, Jan Putzeys, Shiwei Wang, Alexandru Andrei, Veronique Rochus, Marleen Welkenhuysen, Nick van Helleputte, Silke Musa, Robert Puers, Fabian Kloosterman, Chris van Hoof, Richárd Fiáth, István Ulbert, Srinjoy Mitra
We present a high electrode density and high channel count CMOS (complementary metal-oxide-semiconductor) active neural probe containing 1344 neuron sized recording pixels (20 µm × 20 µm) and 12 reference pixels (20 µm × 80 µm), densely packed on a 50 µm thick, 100 µm wide, and 8 mm long shank. The active electrodes or pixels consist of dedicated in-situ circuits for signal source amplification, which are directly located under each electrode. The probe supports the simultaneous recording of all 1356 electrodes with sufficient signal to noise ratio for typical neuroscience applications...
October 19, 2017: Sensors
https://www.readbyqxmd.com/read/29041217/generation-of-high-power-spatially-structured-beams-using-vertical-external-cavity-surface-emitting-lasers
#2
Michal L Lukowski, Jason T Meyer, Chris Hessenius, Ewan M Wright, Mahmoud Fallahi
In this paper, we demonstrate the generation of high-power and spatially structured beams using vertical external cavity surface emitting lasers (VECSEL). At the fundamental wavelength, an intracavity mode-control element is first employed to generate a range of Hermite-Gaussian (HG) modes in a linear cavity. The same HG modes are then excited and frequency doubled in a V-cavity geometry to generate a rich variety of high-power spatially structured beams. The results compare well with our numerical modeling...
October 16, 2017: Optics Express
https://www.readbyqxmd.com/read/29039202/nanoelectronic-platform-for-ultrasensitive-detection-of-protein-biomarkers-in-serum-using-dna-amplification
#3
Luye Mu, Ilia A Droujinine, Jieun Lee, Mathias Wipf, Paschall Davis, Chris Adams, Jennifer Hannant, Mark A Reed
Silicon nanowire field effect transistors (NWFETs) are low noise, low power, ultrasensitive biosensors that are highly amenable to integration. However, using NWFETs to achieve direct protein detection in physiological buffers such as blood serum remains difficult due to Debye screening, nonspecific binding, and stringent functionalization requirements. In this work, we performed an indirect sandwich immunoassay in serum combined with exponential DNA amplification and pH measurement by ultrasensitive NWFET sensors...
October 17, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/29038561/vitamin-d-and-cognitive-function-a-mendelian-randomisation-study
#4
Jane Maddock, Ang Zhou, Alana Cavadino, Elżbieta Kuźma, Yanchun Bao, Melissa C Smart, Kai-Uwe Saum, Ben Schöttker, Jorgen Engmann, Marie Kjærgaard, Ville Karhunen, Yiqiang Zhan, Terho Lehtimäki, Suvi P Rovio, Liisa Byberg, Jari Lahti, Pedro Marques-Vidal, Abhijit Sen, Laura Perna, Henrik Schirmer, Archana Singh-Manoux, Juha Auvinen, Nina Hutri-Kähönen, Mika Kähönen, Lena Kilander, Katri Räikkönen, Håkan Melhus, Erik Ingelsson, Idris Guessous, Katja E Petrovic, Helena Schmidt, Reinhold Schmidt, Peter Vollenweider, Lars Lind, Johan G Eriksson, Karl Michaëlsson, Olli T Raitakari, Sara Hägg, Nancy L Pedersen, Karl-Heinz Herzig, Marjo-Riitta Järvelin, Juha Veijola, Mika Kivimaki, Rolf Jorde, Hermann Brenner, Meena Kumari, Chris Power, David J Llewellyn, Elina Hyppönen
The causal nature of the association between hypovitaminosis D and poor cognitive function in mid- to later-life is uncertain. Using a Mendelian randomisation(MR) approach, we examined the causal relationship between 25(OH)D and cognitive function. Data came from 172,349 participants from 17 cohorts. DHCR7(rs12785878), CYP2R1 rs12794714) and their combined synthesis score were chosen to proxy 25(OH)D. Cognitive tests were standardised into global and memory scores. Analyses were stratified by 25(OH)D tertiles, sex and age...
October 16, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29035598/rpe-during-concentric-and-eccentric-cycling-are-we-measuring-effort-or-exertion
#5
Luis Peñailillo, Karen Mackay, Chris R Abbiss
Despite the terms often being used interchangeably it has been suggested that perceptions of effort and perceptions of exertion may differ. Eccentric cycling may provide a model of exercise by which differences between these perceptions can be examined. PURPOSE: of this study was to examine and compare perceptions of effort and exertion during eccentric and concentric cycling at four intensities. METHODS: Ten healthy male participants (mean ± SD; age: 29.8 ± 2...
October 16, 2017: International Journal of Sports Physiology and Performance
https://www.readbyqxmd.com/read/29033847/a-monetary-reward-alters-pacing-but-not-performance-in-competitive-cyclists
#6
Sabrina Skorski, Kevin G Thompson, Richard J Keegan, Tim Meyer, Chris R Abbiss
Money has frequently been used as an extrinsic motivator since it is assumed that humans are willing to invest more effort for financial reward. However, the influence of a monetary reward on pacing and performance in trained athletes is not well-understood. Therefore, the aim of this study was to analyse the influence of a monetary reward in well-trained cyclists on their pacing and performance during short and long cycling time trials (TT). Twentythree cyclists (6 ♀, 17 ♂) completed 4 self-paced time trials (TTs, 2 short: 4 km and 6 min; 2 long: 20 km and 30 min); in a randomized order...
2017: Frontiers in Physiology
https://www.readbyqxmd.com/read/29025828/diurnal-cortisol-and-mental-well-being-in-middle-and-older-age-evidence-from-four-cohort-studies
#7
Mai Stafford, Yoav Ben-Shlomo, Cyrus Cooper, Catharine Gale, Michael P Gardner, Marie-Claude Geoffroy, Chris Power, Diana Kuh, Rachel Cooper
OBJECTIVES: We conducted an individual participant meta-analysis to test the hypothesis that cortisol patterns indicative of dysregulated hypothalamic-pituitary-adrenal axis functioning would be prospectively associated with poorer well-being at follow-up. SETTING: Four large UK-based cohort studies. PARTICIPANTS: Those providing valid salivary or serum cortisol samples (n=7515 for morning cortisol; n=1612 for cortisol awakening response) at baseline (age 44-82) and well-being data on the Warwick Edinburgh Mental Wellbeing Scale at follow-up (0-8 years) were included...
October 12, 2017: BMJ Open
https://www.readbyqxmd.com/read/29017593/incremental-value-of-biomarker-combinations-to-predict-progression-of-mild-cognitive-impairment-to-alzheimer-s-dementia
#8
Lutz Frölich, Oliver Peters, Piotr Lewczuk, Oliver Gruber, Stefan J Teipel, Hermann J Gertz, Holger Jahn, Frank Jessen, Alexander Kurz, Christian Luckhaus, Michael Hüll, Johannes Pantel, Friedel M Reischies, Johannes Schröder, Michael Wagner, Otto Rienhoff, Stefanie Wolf, Chris Bauer, Johannes Schuchhardt, Isabella Heuser, Eckart Rüther, Fritz Henn, Wolfgang Maier, Jens Wiltfang, Johannes Kornhuber
BACKGROUND: The progression of mild cognitive impairment (MCI) to Alzheimer's disease (AD) dementia can be predicted by cognitive, neuroimaging, and cerebrospinal fluid (CSF) markers. Since most biomarkers reveal complementary information, a combination of biomarkers may increase the predictive power. We investigated which combination of the Mini-Mental State Examination (MMSE), Clinical Dementia Rating (CDR)-sum-of-boxes, the word list delayed free recall from the Consortium to Establish a Registry of Dementia (CERAD) test battery, hippocampal volume (HCV), amyloid-beta1-42 (Aβ42), amyloid-beta1-40 (Aβ40) levels, the ratio of Aβ42/Aβ40, phosphorylated tau, and total tau (t-Tau) levels in the CSF best predicted a short-term conversion from MCI to AD dementia...
October 10, 2017: Alzheimer's Research & Therapy
https://www.readbyqxmd.com/read/29017280/immunogenicity-of-the-13-valent-pneumococcal-conjugate-vaccine-in-older-adults-with-and-without-comorbidities-in-the-community-acquired-pneumonia-immunization-trial-in-adults-capita
#9
Anna M M van Deursen, Marlies A van Houten, Chris Webber, Michael Patton, Daniel A Scott, Scott Patterson, Mohinder Sidhu, Wayne Drews, William C Gruber, Emilio A Emini, Diederick E Grobbee, Marc J M Bonten, Elisabeth A M Sanders
Background: In the randomized controlled Community-Acquired Pneumonia Immunization Trial in Adults (CAPiTA), the efficacy of the 13-valent pneumococcal conjugate vaccine (PCV13) against first episodes of vaccine-type community-acquired pneumonia in adults aged ≥65 years was 46%. The long-term immunogenicity of PCV13 in pneumococcal vaccine-naive older adults was investigated as part of CAPiTA. Methods: We determined the immune responses to PCV13 before and at 1, 12, and 24 months after vaccination in 1006 PCV13 recipients and 1005 controls with 3 age-stratified study participant cohorts...
September 1, 2017: Clinical Infectious Diseases: An Official Publication of the Infectious Diseases Society of America
https://www.readbyqxmd.com/read/28993261/volatile-organic-compounds-in-feces-associate-with-response-to-dietary-intervention-in-patients-with-irritable-bowel-syndrome
#10
Megan Rossi, Raphael Aggio, Heidi M Staudacher, Miranda C Lomer, James O Lindsay, Peter Irving, Chris Probert, Kevin Whelan
BACKGROUND & AIMS: Dietary interventions are effective in management of patients with irritable bowel syndrome (IBS), although responses vary. We investigated whether fecal levels of volatile organic compounds (VOCs) associate with response to dietary interventions in patients with IBS. METHODS: Adults who fulfilled the Rome III criteria for IBS were recruited to a 2x2 factorial randomized controlled trial. Patients were randomly assigned to a group counselled to follow a diet low in fructans, galacto-oligosaccharides, lactose, fructose, and polyols (low-FODMAP diet, n=46) or a group that received placebo dietary advice (sham diet, n=47) for 4 weeks...
October 6, 2017: Clinical Gastroenterology and Hepatology
https://www.readbyqxmd.com/read/28989979/haplotype-based-association-analysis-of-general-cognitive-ability-in-generation-scotland-the-english-longitudinal-study-of-ageing-and-uk-biobank
#11
David M Howard, Mark J Adams, Toni-Kim Clarke, Eleanor M Wigmore, Yanni Zeng, Saskia P Hagenaars, Donald M Lyall, Pippa A Thomson, Kathryn L Evans, David J Porteous, Reka Nagy, Caroline Hayward, Chris S Haley, Blair H Smith, Alison D Murray, G David Batty, Ian J Deary, Andrew M McIntosh
BACKGROUND: Cognitive ability is a heritable trait with a polygenic architecture, for which several associated variants have been identified using genotype-based and candidate gene approaches. Haplotype-based analyses are a complementary technique that take phased genotype data into account, and potentially provide greater statistical power to detect lower frequency variants. METHODS: In the present analysis, three cohort studies (n total = 48,002) were utilised: Generation Scotland: Scottish Family Health Study (GS:SFHS), the English Longitudinal Study of Ageing (ELSA), and the UK Biobank...
2017: Wellcome Open Research
https://www.readbyqxmd.com/read/28983275/cortical-substrate-of-supraspinal-fatigue-following-exhaustive-aerobic-exercise-localizes-to-a-large-cluster-in-the-anterior-premotor-cortex
#12
Priyantha Herath, Martin Carmichael, Angela Murphy, Leonardo Bonilha, Roger Newman-Norlund, Chris Rorden, Mark Davis
Strenuous exercise leads to a progressive reduction in the performance of voluntary physical exercise. This is due to a process described as fatigue and is defined as the failure to maintain the required or expected power output. While some of this is muscular in origin, there are data suggestive of how fatigue is modulated by cortical signals, leading to a concept of central fatigue. The previously reported fatigue-induced changes in cortical activity may have been due to blood oxygen-dependent (BOLD) signal drift and/or neural habituation alone...
2017: Frontiers in Neurology
https://www.readbyqxmd.com/read/28972003/latent-rheumatic-heart-disease-identifying-the-children-at-highest-risk-of-unfavorable-outcome
#13
Andrea Beaton, Twalib Aliku, Alyssa Dewyer, Marni Jacobs, Jiji Jiang, Chris T Longenecker, Sulaiman Lubega, Robert McCarter, Mariana Mirabel, Grace Mirembe, Judith Namuyonga, Emmy Okello, Amy Scheel, Emmanuel Tenywa, Craig Sable, Peter Lwabi
Background -Screening echocardiography (echo) has emerged as a potentially powerful tool for early diagnosis of rheumatic heart disease (RHD). The utility of screening echo hinges on the rate of RHD progression and the ability of penicillin prophylaxis to improve outcome. We report the longitudinal outcomes of a cohort of children with latent RHD and identify risk factors for unfavorable outcomes. Methods -This was a prospective natural history study conducted under the Ugandan RHD registry. Children with latent RHD and ≥1 year of follow-up were included...
September 27, 2017: Circulation
https://www.readbyqxmd.com/read/28971338/fourier-transform-ion-cyclotron-resonance-mass-spectrometry-as-a-platform-for-characterizing-multimeric-membrane-protein-complexes
#14
Jennifer L Lippens, Michael Nshanian, Chris Spahr, Pascal F Egea, Joseph A Loo, Iain D G Campuzano
Membrane protein characterization is consistently hampered by challenges with expression, purification, and solubilization. Among several biophysical techniques employed for their characterization, native-mass spectrometry (MS) has emerged as a powerful tool for the analysis of membrane proteins and complexes. Here, two MS platforms, the FT-ICR and Q-ToF, have been explored to analyze the homotetrameric water channel protein, AquaporinZ (AqpZ), under non-denaturing conditions. This 97 kDa membrane protein complex can be readily liberated from the octylglucoside (OG) detergent micelle under a range of instrument conditions on both MS platforms...
October 2, 2017: Journal of the American Society for Mass Spectrometry
https://www.readbyqxmd.com/read/28968763/jepegmix2-improved-gene-level-joint-analysis-of-eqtls-in-cosmopolitan-cohorts
#15
Chris Chatzinakos, Donghyung Lee, Bradley T Webb, Vladimir I Vladimirov, Kenneth S Kendler, Silviu-Alin Bacanu
Motivation: To increase detection power, researchers use gene level analysis methods to aggregate weak marker signals. Due to gene expression controlling biological processes, researchers proposed aggregating signals for expression Quantitative Trait Loci (eQTL). Most gene-level eQTL methods make statistical inferences based on i) summary statistics from genome-wide association studies (GWAS) and ii) linkage disequilibrium (LD) patterns from a relevant reference panel. While most such tools assume homogeneous cohorts, our Gene-level Joint Analysis of functional SNPs in Cosmopolitan Cohorts (JEPEGMIX) method accommodates cosmopolitan cohorts by using heterogeneous panels...
September 14, 2017: Bioinformatics
https://www.readbyqxmd.com/read/28967993/production-of-purified-casrnps-for-efficacious-genome-editing
#16
Emily Lingeman, Chris Jeans, Jacob E Corn
CRISPR-Cas systems have been harnessed as modular genome editing reagents for functional genomics and show promise to cure genetic diseases. Directed by a guide RNA, a Cas effector introduces a double stranded break in DNA and host cell DNA repair leads to the introduction of errors (e.g., to knockout a gene) or a programmed change. Introduction of a Cas effector and guide RNA as a purified Cas ribonucleoprotein complex (CasRNP) has recently emerged as a powerful approach to alter cell types and organisms. Not only does CasRNP editing exhibit increased efficacy and specificity, it avoids optimization and iteration of species-specific factors such as codon usage, promoters, and terminators...
October 2, 2017: Current Protocols in Molecular Biology
https://www.readbyqxmd.com/read/28965255/snowmelt-timing-phenology-and-growing-season-length-in-conifer-forests-of-crater-lake-national-park-usa
#17
Donal S O'Leary, Jherime L Kellermann, Chris Wayne
Anthropogenic climate change is having significant impacts on montane and high-elevation areas globally. Warmer winter temperatures are driving reduced snowpack in the western USA with broad potential impacts on ecosystem dynamics of particular concern for protected areas. Vegetation phenology is a sensitive indicator of ecological response to climate change and is associated with snowmelt timing. Human monitoring of climate impacts can be resource prohibitive for land management agencies, whereas remotely sensed phenology observations are freely available at a range of spatiotemporal scales...
September 30, 2017: International Journal of Biometeorology
https://www.readbyqxmd.com/read/28947595/the-effect-of-muscle-length-on-transcranial-magnetic-stimulation-induced-relaxation-rate-in-the-plantar-flexors
#18
Alexandra F Yacyshyn, Jane Nettleton, Geoffrey A Power, Jennifer M Jakobi, Chris J McNeil
Transcranial magnetic stimulation (TMS) of the motor cortex during a maximal voluntary contraction (MVC) permits functionally relevant measurements of muscle group relaxation rate (i.e., when muscles are actively contracting under voluntary control). This study's purpose was twofold: (1) to explore the impact of muscle length on TMS-induced plantar flexor relaxation rate; and (2) to incorporate ultrasonography to measure relaxation-induced lengthening of medial gastrocnemius (MG) fascicles and displacement of the muscle-tendon junction (MTJ)...
September 2017: Physiological Reports
https://www.readbyqxmd.com/read/28931500/web-based-cognitive-remediation-improves-supported-employment-outcomes-in-severe-mental-illness-randomized-controlled-trial
#19
Anthony Wf Harris, Tanya Kosic, Jean Xu, Chris Walker, William Gye, Antoinette Redoblado Hodge
BACKGROUND: Finding work is a top priority for most people; however, this goal remains out of reach for the majority of individuals with a severe mental illness (SMI) who remain on benefits or are unemployed. Supported employment (SE) programs aimed at returning people with a severe mental illness to work are successful; however, they still leave a significant number of people with severe mental illness unemployed. Cognitive deficits are commonly found in SMI and are a powerful predictor of poor outcome...
September 20, 2017: JMIR Mental Health
https://www.readbyqxmd.com/read/28911877/validity-and-reliability-of-naturalistic-driving-scene-categorization-judgments-from-crowdsourcing
#20
Christopher D D Cabrall, Zhenji Lu, Miltos Kyriakidis, Laura Manca, Chris Dijksterhuis, Riender Happee, Joost de Winter
A common challenge with processing naturalistic driving data is that humans may need to categorize great volumes of recorded visual information. By means of the online platform CrowdFlower, we investigated the potential of crowdsourcing to categorize driving scene features (i.e., presence of other road users, straight road segments, etc.) at greater scale than a single person or a small team of researchers would be capable of. In total, 200 workers from 46 different countries participated in 1.5days. Validity and reliability were examined, both with and without embedding researcher generated control questions via the CrowdFlower mechanism known as Gold Test Questions (GTQs)...
September 12, 2017: Accident; Analysis and Prevention
keyword
keyword
107367
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"