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https://www.readbyqxmd.com/read/29221761/enrichment-of-pha-producing-bacteria-under-continuous-substrate-supply
#1
Leonie Marang, Mark C M van Loosdrecht, Robbert Kleerebezem
To enrich polyhydroxyalkanoate (PHA) producing microbial communities, generally, a feast-famine regime is applied. Here we investigated the impact of continuous substrate feeding on the enrichment of PHA-producing bacteria in two sequencing batch reactors (SBRs). In the first reactor, the substrate (acetate) was dosed continuously and Zoogloea sp. was enriched. The culture accumulated PHA upon exposure to excess carbon, but the PHA production rate and storage capacity (53wt.%) were one-fifth of that observed for enrichment cultures in a standard, pulse-fed SBR dominated by the PHA producer Plasticicumulans acidivorans...
December 5, 2017: New Biotechnology
https://www.readbyqxmd.com/read/29220309/quantifying-strength-of-chaos-in-the-population-firing-rate-of-neurons
#2
Takashi Kanamaru
In this study, I considered quantifying the strength of chaos in the population firing rate of a pulse-coupled neural network. In particular, I considered the dynamics where the population firing rate is chaotic and the firing of each neuron is stochastic. I calculated a time histogram of firings to show the variation in the population firing rate over time. To smooth this histogram, I used Bayesian adaptive regression splines and a gaussian filter. The nonlinear prediction method, based on reconstruction, was applied to a sequence of interpeak intervals in the smoothed time histogram of firings...
December 8, 2017: Neural Computation
https://www.readbyqxmd.com/read/29219566/dynamical-engineering-of-interactions-in-qudit-ensembles
#3
Soonwon Choi, Norman Y Yao, Mikhail D Lukin
We propose and analyze a method to engineer effective interactions in an ensemble of d-level systems (qudits) driven by global control fields. In particular, we present (i) a necessary and sufficient condition under which a given interaction can be decoupled, (ii) the existence of a universal sequence that decouples any (cancelable) interaction, and (iii) an efficient algorithm to engineer a target Hamiltonian from an initial Hamiltonian (if possible). We illustrate the potential of this method with two examples...
November 3, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/29218494/efficacy-of-pulsed-dye-laser-treatment-for-common-warts-is-not-influenced-by-the-causative-hpv-type-a-prospective-study
#4
Yoseph Fichman, Assi Levi, Emmilia Hodak, Shlomit Halachmi, Sigal Mazor, Dana Wolf, Orit Caplan, Moshe Lapidoth
Verruca vulgaris (VV) is a prevalent skin condition caused by various subtypes of human papilloma virus (HPV). The most common causes of non-genital lesions are HPV types 2 and 4, and to a lesser extent types 1, 3, 26, 29, and 57. Although numerous therapeutic modalities exist, none is universally effective or without adverse events (AE). Pulsed dye laser (PDL) is a favorable option due to its observed efficacy and relatively low AE rate. However, it is not known which verrucae are most likely to respond to PDL, or whether the causative viral subtype influences this response...
December 7, 2017: Lasers in Medical Science
https://www.readbyqxmd.com/read/29217881/reduced-baroreflex-sensitivity-decreased-heart-rate-variability-with-increased-arterial-stiffness-in-predialysis
#5
C Lal, M Kaur, A K Jaryal, K K Deepak, D Bhowmik, S K Agarwal
High cardiovascular morbidity and mortality is observed in predialytic chronic kidney disease (CKD) patients. The underlying mechanism of cardiovascular dysfunction often remains unclear. The present study was designed to perform multiparametric assessment of baroreflex sensitivity (BRS), arterial stiffness indices, and cardiovascular variabilities (heart rate variability [HRV] and blood pressure variability [BPV]) together in predialytic CKD patients; compare it with normal healthy controls; and determine their relationships in predialytic nondiabetic CKD patients...
November 2017: Indian Journal of Nephrology
https://www.readbyqxmd.com/read/29216230/a-comprehensive-scoring-system-in-correlation-with-perioperative-airway-management-for-neonatal-pierre-robin-sequence
#6
Ning Yin, Lei Fang, Xiaohua Shi, Hongqiang Huang, Li Zhang
PURPOSE: To evaluate a comprehensive scoring system which combines clinical manifestations of Pierre Robin Sequence (PRS) including severity of breathing difficulties, body weight and preoperative Cormack-Lehane grade, for its correlation with perioperative PRS airway management decision. DESIGN: Forty PRS children were retrospectively recruited after surgery. Specialists examined all subjects and scored for clinical manifestations (1´ - 4´), weight gain (1´- 4´), dyspnea scores (1´- 4´), and Cormack-Lehane grade (1´- 4´)...
2017: PloS One
https://www.readbyqxmd.com/read/29215148/31-p-t2-s-of-phosphomonoesters-phosphodiesters-and-inorganic-phosphate-in-the-human-brain-at-7t
#7
Wybe J M van der Kemp, Dennis W J Klomp, Jannie P Wijnen
PURPOSE: To determine the phosphorus-31 T2 s of phosphomonoesters, phosphodiesters, and inorganic phosphate in the healthy human brain at 7T. METHODS: A 3D chemical shift imaging multi-echo sequence with composite block pulses for refocusing was used to measure one free induction decay (FID) and seven full echoes with an echo spacing of 45 ms on the brain of nine healthy volunteers (age range 22-45 years; average age 27 ± 8 years). Spectral fitting was used to determine the change in metabolic signal amplitude with echo time...
December 7, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29214264/from-e-to-z-and-back-again-reversible-photoisomerisation-of-an-isolated-charge-tagged-azobenzene
#8
James N Bull, Michael S Scholz, Eduardo Carrascosa, Evan J Bieske
Substituted azobenzenes serve as chromophores and actuators in a wide range of molecular photoswitches. Here, tandem ion mobility spectrometry coupled with laser excitation is used to investigate the photoisomerisation of selected E and Z isomers of the charge-tagged azobenzene, methyl orange. Both isomers display a weak S1(nπ*) photoisomerisation response in the blue part of the spectrum peaking at 440 nm and a more intense S2(ππ*) photoisomerisation response in the near-UV with maxima at 370 and 310 nm for the E and Z isomers, respectively...
December 7, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/29209300/molecular-characteristics-of-st1193-clone-among-phylogenetic-group-b2-non-st131-fluoroquinolone-resistant-escherichia-coli
#9
Jing Wu, Fangjun Lan, Yanfang Lu, Qingwen He, Bin Li
Objectives: Sequence type 1193 is emerging as a new, virulent and resistant lineage among fluoroquinolone resistant Escherichia coli (FQrE. coli). In this study, we investigated the prevalence and molecular characteristics of this clone isolated from a Chinese university hospital. Methods: 73 phylogenetic group B2-FQr-non-ST131 isolates were collected from August 2014 and August 2015 at a Chinese university hospital. Isolates were screened for ST1193 by multilocus sequence typing. E. coli ST1193 then underwent lactose fermentation determination, susceptibility testing, virulence genotyping, PCR-based O typing, pulsed-field gel electrophoresis (PFGE) and FQr mechanism analysis...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/29209292/characterization-of-colistin-resistant-escherichia-coli-isolated-from-diseased-pigs-in-france
#10
Sabine Delannoy, Laetitia Le Devendec, Eric Jouy, Patrick Fach, Djamel Drider, Isabelle Kempf
We studied a collection of 79 colistin-resistant Escherichia coli isolates isolated from diseased pigs in France between 2009 and 2013. We determined a number of phenotypic and genetic characters using broth microdilution to characterize their antimicrobial susceptibility. We performed pulse field gel electrophoresis (PFGE) to assess their genetic diversity and assign them to phylogroups. High-throughput real-time PCR micro-array was used to screen for a selection of genetic markers of virulence, and PCR and sequencing of the main recognized resistance genes allowed us to investigate the mechanisms of colistin resistance...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/29208823/zepto-precision-pulse-capsulotomy-a-new-automated-and-disposable-capsulotomy-technology
#11
David F Chang
Despite the appeal of an automated method of creating a perfectly circular anterior capsulotomy, global adoption of femtosecond laser capsulotomy (FSLC) has been limited by its high acquisition and per case cost. In addition, the femtosecond laser's large size and the need for eye docking create surgical efficiency and workflow challenges. The Zepto precision pulse capsulotomy (PPC) technology creates a circular anterior capsulotomy of a precise diameter using a disposable handpiece and tip that are used in the normal surgical sequence...
December 2017: Indian Journal of Ophthalmology
https://www.readbyqxmd.com/read/29204016/usefulness-of-pulsed-arterial-spin-labeling-magnetic-resonance-imaging-in-new-onset-seizure-patients-and-its-comparison-with-dynamic-susceptibility-contrast-magnetic-resonance-imaging
#12
Varun Bansal, Suresh Kumar, Sudhir Sharma, Sanjiv Sharma, R G Sood
Introduction: Dynamic susceptibility contrast (DSC) perfusion and pulsed arterial spin labeling (PASL) imaging are newer advanced magnetic resonance sequences which are capable of detecting vascular changes in patients with new-onset seizure disorder even when no significant abnormalities are visualized on conventional sequences. The purpose of our study is to establish utility of arterial spin labeling (ASL) in new-onset seizure patients and compare ASL with DSC perfusion sequence. Materials and Methods: Twenty-six patients coming to emergency department with new-onset seizure disorder were evaluated using DSC and ASL sequence...
October 2017: Journal of Neurosciences in Rural Practice
https://www.readbyqxmd.com/read/29195336/control-of-electrical-turbulence-by-periodic-excitation-of-cardiac-tissue
#13
Pavel Buran, Markus Bär, Sergio Alonso, Thomas Niedermayer
Electrical turbulence in cardiac tissue is associated with arrhythmias such as life-threatening ventricular fibrillation. Recent experimental studies have shown that a sequence of low-energy electrical far-field pulses is able to terminate fibrillation more gently than a single high-energy pulse which causes severe side effects. During this low-energy antifibrillation pacing (LEAP), only tissue near sufficiently large conduction heterogeneities, such as large coronary arteries, is activated. In order to optimize LEAP, we performed extensive simulations of cardiac tissue perforated by blood vessels, employing two alternative cellular models that exhibit electrical turbulence at a similar length scale...
November 2017: Chaos
https://www.readbyqxmd.com/read/29194739/transverse-signal-decay-under-the-weak-field-approximation-theory-and-validation
#14
Avery J L Berman, G Bruce Pike
PURPOSE: To derive an expression for the transverse signal time course from systems in the motional narrowing regime, such as water diffusing in blood. This was validated in silico and experimentally with ex vivo blood samples. METHODS: A closed-form solution (CFS) for transverse signal decay under any train of refocusing pulses was derived using the weak field approximation. The CFS was validated via simulations of water molecules diffusing in the presence of spherical perturbers, with a range of sizes and under various pulse sequences...
December 1, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29194732/doppler-ultrasound-triggering-for-cardiac-mri-at-7t
#15
F Kording, C Ruprecht, B Schoennagel, K Fehrs, J Yamamura, G Adam, J Goebel, K Nassenstein, S Maderwald, H H Quick, O Kraff
PURPOSE: A prerequisite for cardiac MR (CMR) imaging is adequate synchronization of image acquisition with the cardiac cycle. Electrocardiogram triggering may be hampered by electromagnetic interferences at high field strength. The purpose of this work is to evaluate the feasibility of Doppler ultrasound triggering for CMR image synchronization at 7T ultra-high-field MRI. METHODS: A custom-built Doppler ultrasound (DUS) trigger device was developed. Magnetic resonance compatibility was evaluated using E- and H-field probes and flip angle maps prior to the study...
December 1, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29193406/online-1-h-mrs-measurements-of-time-varying-lactate-production-in-an-animal-model-of-glioma-during-administration-of-an-anti-tumoral-drug
#16
Yannick Crémillieux, Roberto Salvati, Ursule Dumont, Noël Pinaud, Véronique Bouchaud, Stéphane Sanchez, Stefan Glöggler, Alan Wong
The aims of this study were to implement a magnetic resonance spectroscopy (MRS) protocol for the online profiling of subnanomolar quantities of metabolites sampled from the extracellular fluid using implanted microdialysis and to apply this protocol in glioma-bearing rats for the quantification of lactate concentration and the measurement of time-varying lactate concentration during drug administration. MRS acquisitions on the brain microdialysate were performed using a home-built, proton-tuned, microsolenoid with an active volume of 2 μL...
November 29, 2017: NMR in Biomedicine
https://www.readbyqxmd.com/read/29193266/motion-tolerant-diffusion-mapping-based-on-single-shot-overlapping-echo-detachment-oled-planar-imaging
#17
Lingceng Ma, Congbo Cai, Hongyi Yang, Shuhui Cai, Junchao Qian, Lizhi Xiao, Kai Zhong, Zhong Chen
PURPOSE: A new diffusion-mapping method based on single-shot overlapping-echo detachment (DM-OLED) planar-imaging sequence, along with a corresponding separation algorithm, is proposed to achieve reliable quantitative diffusion mapping in a single shot. The method can resist the effects of motion and help in detecting the quick variation of diffusion under different physiological status. METHODS: The echo-planar imaging method is combined with two excitation pulses with small flip angle to gain overlapping-echo signal in a single shot...
November 28, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29193250/design-of-universal-parallel-transmit-refocusing-kt-point-pulses-and-application-to-3d-t2-weighted-imaging-at-7t
#18
Vincent Gras, Franck Mauconduit, Alexandre Vignaud, Alexis Amadon, Denis Le Bihan, Tony Stöcker, Nicolas Boulant
PURPOSE: T2 -weighted sequences are particularly sensitive to the radiofrequency (RF) field inhomogeneity problem at ultra-high-field because of the errors accumulated by the imperfections of the train of refocusing pulses. As parallel transmission (pTx) has proved particularly useful to counteract RF heterogeneities, universal pulses were recently demonstrated to save precious time and computational efforts by skipping B1 calibration and online RF pulse tailoring. Here, we report a universal RF pulse design for non-selective refocusing pulses to mitigate the RF inhomogeneity problem at 7T in turbo spin-echo sequences with variable flip angles...
November 29, 2017: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
https://www.readbyqxmd.com/read/29191732/quantification-of-aortic-valve-regurgitation-by-pulsed-doppler-examination-of-the-left-subclavian-artery-velocity-contour-a-validation-study-with-cardiovascular-magnetic-resonance-imaging
#19
Ricardo A Spampinato, Cosima Jahnke, Ingo Paetsch, Sebastian Hilbert, Franziska Busch, Valerie Schloma, Yaroslava Dmitrieva, Fernanda Bonamigo Thome, Susanne Löbe, Elfriede Strotdrees, Gerhard Hindricks, Friedrich-Wilhelm Mohr, Michael A Borger
BACKGROUND: Reflux of the aortic regurgitation (AR) causes an increased diastolic reverse flow in the aorta and its branching vessels. We aimed to evaluate the feasibility and accuracy of Doppler measurements in the left subclavian artery (LSA) for quantification of AR in a cardiovascular magnetic resonance imaging (CMR) validation study. METHODS: Systolic and diastolic flow profiles of the LSA (subclavicular approach) were evaluated prospectively by use of pulsed wave Doppler in 59 patients (55...
November 28, 2017: Journal of the American Society of Echocardiography
https://www.readbyqxmd.com/read/29190721/carriage-of-staphylococcus-aureus-among-portuguese-nursing-students-a-longitudinal-cohort-study-over-four-years-of-education
#20
Teresa Conceição, Hermínia de Lencastre, Marta Aires-de-Sousa
BACKGROUND: Staphylococcus aureus is a major human pathogen that can colonize healthy people mainly in the anterior nares. The aim of the present study was to evaluate S. aureus nasal colonization over time among Portuguese nursing students, including methicillin-resistant S. aureus (MRSA). METHODS AND FINDINGS: In this longitudinal cohort study, we collected 280 nasal swabs from nursing students at 14 time points over four years of schooling (2012-2016). The isolates were characterized by pulsed-field gel electrophoresis (PFGE), spa typing, multilocus sequence typing (MLST), and SCCmec typing for MRSA...
2017: PloS One
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