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https://www.readbyqxmd.com/read/29026092/response-of-microbial-biomass-and-co2-c-loss-to-wetting-patterns-are-temperature-dependent-in-a-semi-arid-soil
#1
Yichao Rui, Deirdre B Gleeson, Daniel V Murphy, Frances C Hoyle
One of the greatest contemporary challenges in terrestrial ecology is to determine the impact of climate change on the world's ecosystems. Here we investigated how wetting patterns (frequency and intensity) and nutrient additions altered microbial biomass and CO2-C loss from a semi-arid soil. South-western Australia is predicted to experience declining annual rainfall but increased frequency of summer rainfall events when soil is fallow. Agricultural soils (0-10 cm at 10 °C or 25 °C) received the same total amount of water (15 mL over 30 days) applied at different frequency; with either nil or added nitrogen and phosphorus...
October 12, 2017: Scientific Reports
https://www.readbyqxmd.com/read/29025748/compromised-cerebrovascular-regulation-and-cerebral-oxygenation-in-pulmonary-arterial-hypertension
#2
Simon Malenfant, Patrice Brassard, Myriam Paquette, Olivier Le Blanc, Audrey Chouinard, Valérie Nadeau, Philip D Allan, Yu-Chieh Tzeng, Sébastien Simard, Sébastien Bonnet, Steeve Provencher
BACKGROUND: Functional cerebrovascular regulatory mechanisms are important for maintaining constant cerebral blood flow and oxygen supply in heathy individuals and are altered in heart failure. We aim to examine whether pulmonary arterial hypertension (PAH) is associated with abnormal cerebrovascular regulation and lower cerebral oxygenation and their physiological and clinical consequences. METHODS AND RESULTS: Resting mean flow velocity in the middle cerebral artery mean flow velocity in the middle cerebral artery (MCAvmean); transcranial Doppler), cerebral pressure-flow relationship (assessed at rest and during squat-stand maneuvers; analyzed using transfer function analysis), cerebrovascular reactivity to CO2, and central chemoreflex were assessed in 11 patients with PAH and 11 matched healthy controls...
October 12, 2017: Journal of the American Heart Association
https://www.readbyqxmd.com/read/29020572/variability-in-the-primary-emissions-and-secondary-gas-and-particle-formation-from-vehicles-using-bio-ethanol-mixtures
#3
E Gramsch, V Papapostolou, F Reyes, Y Vásquez, M Castillo, P Oyola, G López, A Cádiz, S Ferguson, M Wolfson, J Lawrence, P Koutrakis
Bioethanol for use in vehicles is becoming a substantial part of global energy infrastructure because it is renewable and some emissions are reduced. Carbon monoxide (CO) emissions and total hydrocarbons (THC) are reduced but there is still controversy regarding emissions of nitrogen oxides (NOx), aldehydes and ethanol, this may be a concern because all these compounds are precursors of ozone and secondary organic aerosol (SOA). The amount of emissions depends on the ethanol content, but also may depend on the engine quality and ethanol origin...
October 11, 2017: Journal of the Air & Waste Management Association
https://www.readbyqxmd.com/read/29018470/phakopsora-euvitis-causes-unusual-damage-to-leaves-and-modifies-carbohydrate-metabolism-in-grapevine
#4
Antonio F Nogueira Júnior, Rafael V Ribeiro, Beatriz Appezzato-da-Glória, Marli K M Soares, Júlia B Rasera, Lilian Amorim
Asian grapevine rust (Phakopsora euvitis) is a serious disease, which causes severe leaf necrosis and early plant defoliation. These symptoms are unusual for a strict biotrophic pathogen. This work was performed to quantify the effects of P. euvitis on photosynthesis, carbohydrates, and biomass accumulation of grapevine. The reduction in photosynthetic efficiency of the green leaf tissue surrounding the lesions was quantified using the virtual lesion concept (β parameter). Gas exchange and responses of CO2 assimilation to increasing intercellular CO2 concentration were analyzed...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28990307/physiological-dead-space-and-arterial-carbon-dioxide-contributions-to-exercise-ventilatory-inefficiency-in-patients-with-reduced-or-preserved-ejection-fraction-heart-failure
#5
Erik H Van Iterson, Bruce D Johnson, Barry A Borlaug, Thomas P Olson
AIMS: Patients with heart failure (HF) with reduced (HFrEF) or preserved (HFpEF) ejection fraction demonstrate an increased ventilatory equivalent for carbon dioxide (V̇E /V̇CO2 ) slope. The physiological correlates of the V̇E /V̇CO2 slope remain unclear in the two HF phenotypes. We hypothesized that changes in the physiological dead space to tidal volume ratio (VD /VT ) and arterial CO2 tension (PaCO2 ) differentially contribute to the V̇E /V̇CO2 slope in HFrEF vs. HFpEF. METHODS AND RESULTS: Adults with HFrEF (n = 32) and HFpEF (n = 27) [mean ± standard deviation (SD) left ventricular ejection fraction: 22 ± 7% and 61 ± 9%, respectively; mean ± SD body mass index: 28 ± 4 kg/m(2) and 33 ± 6 kg/m(2) , respectively; P < 0...
October 8, 2017: European Journal of Heart Failure
https://www.readbyqxmd.com/read/28974075/elevated-preoperative-heart-rate-is-associated-with-cardiopulmonary-and-autonomic-impairment-in-high-risk-surgical-patients
#6
T E F Abbott, G Minto, A M Lee, R M Pearse, G L Ackland
Background: Elevated preoperative heart rate (HR) is associated with perioperative myocardial injury and death. In apparently healthy individuals, high resting HR is associated with development of cardiac failure. Given that patients with overt cardiac failure have poor perioperative outcomes, we hypothesized that subclinical cardiac failure, identified by cardiopulmonary exercise testing, was associated with elevated preoperative HR > 87 beats min -1 (HR > 87). Methods: This was a secondary analysis of an observational cohort study of surgical patients aged ≥45 yr...
July 1, 2017: British Journal of Anaesthesia
https://www.readbyqxmd.com/read/28954703/nitrogen-and-phosphorus-enrichment-effects-on-co2-and-methane-fluxes-from-an-upland-ecosystem
#7
William A V Stiles, Edwin C Rowe, Peter Dennis
Reactive nitrogen (N) deposition can affect many ecosystem processes, particularly in oligotrophic habitats, and is expected to affect soil C storage potential through increases in microbial decomposition rate as a consequence of greater N availability. Increased N availability may also result in changes in the principal limitations on ecosystem productivity. Phosphorus (P) limitation may constrain productivity in instances of high N deposition, yet ecosystem responses to P availability are poorly understood...
September 24, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28945759/catalase-activity-of-igg-antibodies-from-the-sera-of-healthy-donors-and-patients-with-schizophrenia
#8
Evgeny A Ermakov, Ludmila P Smirnova, Nikolay A Bokhan, Arkadiy V Semke, Svetlana A Ivanova, Valentina N Buneva, Georgy A Nevinsky
We present first evidence showing that some electrophoretically homogeneous IgGs from the sera of patients with schizophrenia (36.4%) and their Fab and F(ab)2 fragments as well as from healthy donors (33.3%) possess catalase activity. The relative catalase activity of IgGs from the sera of individual schizophrenia patients (and healthy donors) significantly varied from patient to patient, but the activity of IgGs from healthy donors is on average 15.8-fold lower than that for schizophrenia patients. After extensive dialysis of purified IgGs against EDTA chelating metal ions, the relative catalase activity of IgGs decreases on average approximately 2...
2017: PloS One
https://www.readbyqxmd.com/read/28915226/pulmonary-vascular-function-and-aerobic-exercise-capacity-at-moderate-altitude
#9
Vitalie Faoro, Gael Deboeck, Marco Vicenzi, Anne-Fleur Gaston, Bamodi Simaga, Grégory Doucende, Ilona Hapkova, Emma Roca, Enric Subirats, Fabienne Durand, Robert Naeije
PURPOSE: There has been suggestion that a greater "pulmonary vascular reserve" defined by a low pulmonary vascular resistance (PVR) and a high lung diffusing capacity (DL) allow for a superior aerobic exercise capacity. How pulmonary vascular reserve might affect exercise capacity at moderate altitude is not known. METHODS: Thirty-eight healthy subjects underwent an exercise stress echocardiography of the pulmonary circulation, combined with measurements of DL for nitric oxide (NO) and carbon monoxide (CO) and a cardiopulmonary exercise test at sea level and at an altitude of 2250 m...
October 2017: Medicine and Science in Sports and Exercise
https://www.readbyqxmd.com/read/28888452/inactivation-mechanism-of-vibrio-parahaemolyticus-via-supercritical-carbon-dioxide-treatment
#10
Feiyue Xu, Xiaomei Feng, Xiao Sui, Hong Lin, Yuqian Han
The effects of supercritical carbon dioxide (SC-CO2) treatments on Vibrio parahaemolyticus cells were determined using viable plate count method at different treatment times (10 and 40min), pressures (10-25MPa), and temperature (40°C). Using the changes in the physical (absorbance, transmission electron microscope and contents of fatty acids) and chemical indexes (pH value, activity of Na(+)K(+)-ATPase, SDS-PAGE) were for further understand the mechanisms of bacterial inactivation under SC-CO2. The result showed that 25MPa treatment for 40min in 40°C could significantly (P<0...
October 2017: Food Research International
https://www.readbyqxmd.com/read/28834605/electrocatalytic-conversion-of-co2-and-nitrate-ions-to-urea-below-1-0-v-vs-ag-agcl-by-a-tio2-nafion%C3%A2-composite-electrode
#11
Saravanakumar Duraisamy, Jieun Song, Sunhye Lee, Namhwi Hur, Woonsup Shin
CO2 and nitrate ions were successfully converted to urea by a TiO2/Nafion® nanocomposite electrode under ambient conditions. The composite electrode was constructed by drop-casting the mixture of P-25 titania and Nafion® solution on an ITO electrode. When the electrode was electrolyzed in CO2-saturated 0.1 M KNO3 (pH 4.5) solution at -0.98 V vs. Ag/AgCl, urea was formed with a Faradaic efficiency of 40%. The other reduced products obtained were ammonia, CO, and H2.
August 23, 2017: ChemSusChem
https://www.readbyqxmd.com/read/28827165/reproducibility-of-task-activation-using-the-addenbrooke-s-cognitive-examination-in-healthy-controls-a-functional-transcranial-doppler-ultrasonography-study
#12
L Beishon, C A L Williams, R B Panerai, T G Robinson, V J Haunton
INTRODUCTION: Cerebral blood flow velocity (CBFv) changes occurring with cognitive stimulation can be measured by Transcranial Doppler ultrasonography (TCD). The aim of this study was to assess the reproducibility of CBFv changes to the Addenbrooke's cognitive examination (ACE-III). NEW METHOD: 13 volunteers underwent bilateral TCD (middle cerebral artery), continuous heart rate (HR, 3-lead ECG, Finometer), beat-to-beat mean arterial pressure (MAP, Finometer), and end-tidal CO2 (ETCO2, capnography)...
November 1, 2017: Journal of Neuroscience Methods
https://www.readbyqxmd.com/read/28826405/genomic-analysis-of%C3%A2-methanogenic-archaea%C3%A2-reveals-a-shift-towards-energy-conservation
#13
Sean P Gilmore, John K Henske, Jessica A Sexton, Kevin V Solomon, Susanna Seppälä, Justin I Yoo, Lauren M Huyett, Abe Pressman, James Z Cogan, Veronika Kivenson, Xuefeng Peng, YerPeng Tan, David L Valentine, Michelle A O'Malley
BACKGROUND: The metabolism of archaeal methanogens drives methane release into the environment and is critical to understanding global carbon cycling. Methanogenesis operates at a very low reducing potential compared to other forms of respiration and is therefore critical to many anaerobic environments. Harnessing or altering methanogen metabolism has the potential to mitigate global warming and even be utilized for energy applications. RESULTS: Here, we report draft genome sequences for the isolated methanogens Methanobacterium bryantii, Methanosarcina spelaei, Methanosphaera cuniculi, and Methanocorpusculum parvum...
August 21, 2017: BMC Genomics
https://www.readbyqxmd.com/read/28806551/effects-of-agricultural-land-use-on-fluvial-carbon-dioxide-methane-and-nitrous-oxide-concentrations-in-a-large-european-river-the-meuse-belgium
#14
A V Borges, F Darchambeau, T Lambert, S Bouillon, C Morana, S Brouyère, V Hakoun, A Jurado, H-C Tseng, J-P Descy, F A E Roland
We report a data-set of CO2, CH4, and N2O concentrations in the surface waters of the Meuse river network in Belgium, obtained during four surveys covering 50 stations (summer 2013 and late winter 2013, 2014 and 2015), from yearly cycles in four rivers of variable size and catchment land cover, and from 111 groundwater samples. Surface waters of the Meuse river network were over-saturated in CO2, CH4, N2O with respect to atmospheric equilibrium, acting as sources of these greenhouse gases to the atmosphere, although the dissolved gases also showed marked seasonal and spatial variations...
January 1, 2018: Science of the Total Environment
https://www.readbyqxmd.com/read/28776683/hypercapnia-induced-active-expiration-increases-in-sleep-and-enhances-ventilation-in-unanaesthetized-rats
#15
Isabela P Leirão, Carlos A Silva, Luciane H Gargaglioni, Glauber S F da Silva
Expiration is passive at rest but becomes active through recruitment of abdominal muscles under increased respiratory drive. Hypercapnia-induced active expiration has not been well explored in unanaesthetized rats. We hypothesized that (i) CO2 -evoked active expiration is recruited in a state-dependent manner i.e. differently in sleep or wakefulness and (ii) that recruitment of active expiration enhances ventilation, hence having an important functional role in meeting metabolic demand. To test these hypotheses Wistar rats (280-330 g) were implanted with electrodes for electroencephalography (EEG) and electromyography (EMG) of the neck, diaphragm (DIA) and abdominal (ABD) muscles...
August 3, 2017: Journal of Physiology
https://www.readbyqxmd.com/read/28775283/structural-basis-for-the-mechanism-of-atp-dependent-acetone-carboxylation
#16
Florence Mus, Brian J Eilers, Alexander B Alleman, Burak V Kabasakal, Jennifer N Wells, James W Murray, Boguslaw P Nocek, Jennifer L DuBois, John W Peters
Microorganisms use carboxylase enzymes to form new carbon-carbon bonds by introducing carbon dioxide gas (CO2) or its hydrated form, bicarbonate (HCO3(-)), into target molecules. Acetone carboxylases (ACs) catalyze the conversion of substrates acetone and HCO3(-) to form the product acetoacetate. Many bicarbonate-incorporating carboxylases rely on the organic cofactor biotin for the activation of bicarbonate. ACs contain metal ions but not organic cofactors, and use ATP to activate substrates through phosphorylation...
August 3, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28765670/microleakage-in-class-v-composite-restorations-after-desensitizing-surface-treatment-with-er-yag-and-co2-lasers
#17
Hamid Reza Mozaffari, Alireza Ehteshami, Farshad Zallaghi, Nasim Chiniforush, Zohreh Moradi
Aims: Glutaraldehyde, CO2 and Er:YAG lasers can be used for treatment of dentin hypersensitivity. However, their application may have adverse effects on the clinical service of restorations. This study aimed to assess the microleakage in composite restorations following surface treatment with Glutaraldehyde desensitizer, CO2 and Er:YAG laser irradiation for treatment of dentin hypersensitivity. Materials and methods: This experimental study was conducted on 60 extracted sound human teeth. Class V cavities were prepared measuring 3×3 mm using a diamond bur...
December 30, 2016: Laser Therapy
https://www.readbyqxmd.com/read/28762180/optimum-support-by-high-flow-nasal-cannula-in-acute-hypoxemic-respiratory-failure-effects-of-increasing-flow-rates
#18
Tommaso Mauri, Laura Alban, Cecilia Turrini, Barbara Cambiaghi, Eleonora Carlesso, Paolo Taccone, Nicola Bottino, Alfredo Lissoni, Savino Spadaro, Carlo Alberto Volta, Luciano Gattinoni, Antonio Pesenti, Giacomo Grasselli
PURPOSE: Limited data exist on the correlation between higher flow rates of high-flow nasal cannula (HFNC) and its physiologic effects in patients with acute hypoxemic respiratory failure (AHRF). We assessed the effects of HFNC delivered at increasing flow rate on inspiratory effort, work of breathing, minute ventilation, lung volumes, dynamic compliance and oxygenation in AHRF patients. METHODS: A prospective randomized cross-over study was performed in non-intubated patients with patients AHRF and a PaO2/FiO2 (arterial partial pressure of oxygen/fraction of inspired oxygen) ratio of ≤300 mmHg...
July 31, 2017: Intensive Care Medicine
https://www.readbyqxmd.com/read/28724918/contrast-enhancement-of-biological-nanoporous-materials-with-zinc-oxide-infiltration-for-electron-and-x-ray-nanoscale-microscopy
#19
L E Ocola, V Sampathkumar, N Kasthuri, R P Winarski
We show that using infiltration of ZnO metal oxide can be useful for high resolution imaging of biological samples in electron and X-ray microscopy. The method is compatible with standard fixation techniques that leave the sample dry, such as finishing with super critical CO2 drying, or simple vacuum drying up to 95 °C. We demonstrate this technique can be applied on tooth and brain tissue samples. We also show that high resolution X-ray tomography can be performed on biological systems using Zn K edge (1s) absorption to enhance internal structures, and obtained the first nanoscale 10 KeV X-ray absorption images of the interior regions of a tooth...
July 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28713699/transoral-thyroidectomy-why-is-it-needed
#20
REVIEW
Gianlorenzo Dionigi, Matteo Lavazza, Chei-Wei Wu, Hui Sun, Xiaoli Liu, Ralph P Tufano, Hoon Yub Kim, Jeremy D Richmon, Angkoon Anuwong
Transoral thyroidectomy (TOT) represents reasonably the desirable minimally invasive approach to the gland due to the scarless non-visible incisions, the limited distance between the gland and the access that minimize tissue dissection and respect of the surgical anatomical planes. Patients are routinely selected according to an extensive inclusion criteria: (I) ultrasonographically (US) estimated thyroid diameter not larger than 10 cm; (II) US gland volume ≤45 mL; (III) nodule size ≤50 mm; (IV) a benign tumor, such as a thyroid cyst, single-nodular goiter, or multinodular goiter; (V) follicular neoplasm; (VI) papillary microcarcinoma without lymph node metastasis...
June 2017: Gland Surgery
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