Read by QxMD icon Read

respiration rate

Tao Bao, Renbin Zhu, Xianglan Li, Wenjuan Ye, Xiao Cheng
Summertime ecosystem respiration (ER) rates through seven sites were measured at an upland tundra on Fildes Peninsula in maritime Antarctica to investigate effects of topographic gradient, vegetation types and climatic factors on tundra ER rates. Overall the highest ER rates occurred at the tundra top, followed at the middle slope, and the lowest rates at the lower slope. The daily highest ER rates occurred at noon whereas the lowest at 6 am. There was a significant positive correlation (P < 0.05) between tundra ER and 0-10 cm soil temperature, but a significant negative correlation (P < 0...
August 17, 2018: Scientific Reports
Tímea Komlódi, Fanni F Geibl, Matilde Sassani, Attila Ambrus, László Tretter
Succinate-driven reverse electron transport (RET) is one of the main sources of mitochondrial reactive oxygen species (mtROS) in ischemia-reperfusion injury. RET is dependent on mitochondrial membrane potential (Δψm ) and transmembrane pH difference (ΔpH), components of the proton motive force (pmf); a decrease in Δψm and/or ΔpH inhibits RET. In this study we aimed to determine which component of the pmf displays the more dominant effect on RET-provoked ROS generation in isolated guinea pig brain and heart mitochondria respiring on succinate or α-glycerophosphate (α-GP)...
August 17, 2018: Journal of Bioenergetics and Biomembranes
Jianbo Cheng, Yucheng Chen, Tengbing He, Renlu Liu, Man Yi, Zhimin Yang
Ammonium (NH4 + ) in biogas slurries is readily nitrified into very mobile soil nitrate (NO3 - ) to promote nitrogen (N) leaching concerning which a few studies, however, have been reported. These slurries are regularly applied through irrigation to purple soil in the Three Gorges Reservoir Area, and therefore we explored the consequent N leaching there with a plot experiment. Biogas slurry irrigation was carried out with nitrogen application rates of 0, 48, 144, 240, 336, and 480 kg N/ha. As a result, the last two rates have triggered N leaching being detrimental to groundwater safety...
August 15, 2018: Environmental Science and Pollution Research International
Louis-Pierre Comeau, Derrick Y F Lai, Jane Jinglan Cui, Jodie Hartill
Ex-situ measurement of soil respiration is usually done with highly disturbed samples that may confound the interpretation and extrapolation of results. We have developed a lab respiration assessment method that better simulates field conditions and allows efflux estimations based on soil surface area. First, intact soil cores are extracted in the field and transferred to the lab. Next, soil moisture content and bulk density are assessed in each soil core. Immediately following this the soil cores are gently broken, pooled per treatment (or plot) and the root systems removed...
2018: MethodsX
Pierre-Andre Barbeau, Paula M Miotto, Graham P Holloway
The mechanisms regulating oxidative phosphorylation during exercise remain poorly defined, however key mitochondrial proteins, including carnitine-palmitoyl transferase-I (CPT-I) and adenine-nucleotide translocase have redox sensitive sites. Interestingly muscle contraction has recently been shown to increase mitochondrial membrane potential and reactive oxygen species (ROS) production, therefore we aimed to determine if mitochondrial derived ROS influences bioenergetic responses to exercise. Specifically, we examined the influence of acute exercise on mitochondrial bioenergetics in WT and transgenic mice (MCAT) possessing attenuated mitochondrial ROS...
August 15, 2018: Biochemical Journal
Matthew A Birk, Agnieszka K Dymowska, Brad A Seibel
Squids are thought to obtain a large portion of their oxygen via simple diffusion across the skin in addition to uptake at the gills. Although this hypothesis has support from indirect evidence and is widely accepted, no empirical examinations have been conducted to assess the validity of this hypothesis. In this study, we examined cutaneous respiration in two squid species, Doryteuthis pealeii and Lolliguncula brevis , by using a divided chamber to physically separate the mantle cavity and gills from the outer mantle surface...
August 15, 2018: Journal of Experimental Biology
David H Jang, Shawn Owiredu, Abhay Ranganathan, David M Eckmann
While barotrauma, decompression sickness and drowning-related injuries are common morbidities associated with diving and decompression from depth, it remains unclear what impact rapid decompression has on mitochondrial function. In vitro diving simulation was performed with human dermal fibroblast cells subjected to control, air, nitrogen and oxygen dive conditions. With the exception of gas mixture, all other related variables including absolute pressure exposure, dive and decompression rates, and temperature were held constant...
August 15, 2018: American Journal of Physiology. Cell Physiology
Xavier Portell, Valérie Pot, Patricia Garnier, Wilfred Otten, Philippe C Baveye
There is still no satisfactory understanding of the factors that enable soil microbial populations to be as highly biodiverse as they are. The present article explores in silico the hypothesis that the heterogeneous distribution of soil organic matter, in addition to the spatial connectivity of the soil moisture, might account for the observed microbial biodiversity in soils. A multi-species, individual-based, pore-scale model is developed and parameterized with data from 3 Arthrobacter sp. strains, known to be, respectively, competitive, versatile, and poorly competitive...
2018: Frontiers in Microbiology
Luis F Pieretti, Yehia Y Hammad
Background: Evaluation of the performance of a whole-body human dust exposure chamber is presented in this report. Methods: The volume of the chamber is 2.13 m3 and it is operated at a flow rate of 1.0 m3 /min. Makeup and exhaust air were filtered. A Wright Dust Feeder was used to generate fly ash, the testing agent. An elutriator was used to maintain particles in the respirable range. A Rupprecht and Patashnick PM-10 TEOM, a direct reading instrument, was used to monitor particle concentration...
2018: Toxicology Reports
Chin-Man Wang, Wann-Yun Shieh, Chan-Shien Ho, Yu-Wei Hu, Yih-Ru Wu
Introduction: The coordination of swallowing and respiration is important for safety swallowing without aspiration. This coordination was affected in Parkinson disease (PD). A noninvasive assessment tool was used to investigate the effect of an easy-to-perform and device-free home-based orolingual exercise (OLE) program on swallowing and respiration coordination in patients with early-stage PD. Materials and Methods: This study had a quasi-experimental before-and-after exercise program design. Twenty six patients with early-stage PD who were aged 62...
2018: Frontiers in Neurology
Nathaniel R Glasser, Paul H Oyala, Thomas H Osborne, Joanne M Santini, Dianne K Newman
Arsenate respiration by bacteria was discovered over two decades ago and is catalyzed by diverse organisms using the well-conserved Arr enzyme complex. Until now, the mechanisms underpinning this metabolism have been relatively opaque. Here, we report the structure of an Arr complex (solved by X-ray crystallography to 1.6-Å resolution), which was enabled by an improved Arr expression method in the genetically tractable arsenate respirer Shewanella sp. ANA-3. We also obtained structures bound with the substrate arsenate (1...
August 13, 2018: Proceedings of the National Academy of Sciences of the United States of America
Jerome Ogee, Lisa Wingate, Bernard Genty
Carbonic anhydrase (CA) activity in leaves catalyses the 18O exchange between CO2 and water during photosynthesis. This feature has been used to estimate the mesophyll conductance to CO2 (gm) from measurements of online C18OO photosynthetic discrimination (∆18O). Based on CA assays on leaf extracts, it has been argued that CO2 in mesophyll cells should be in isotopic equilibrium with water in most C3 species as well as many C4 dicot species. However, this seems incompatible with ∆18O data that would indicate a much lower degree of equilibration, especially in C4 plants under high light intensity...
August 13, 2018: Plant Physiology
D H Poole, S E Lyons, R K Poole, M H Poore
Fescue toxicosis is a syndrome that impairs growth and reproduction in cattle grazing endophyte-infected tall fescue [Lolium arundinaceum [(Schreb.].) Darbysh)] in the U.S., resulting in approximately $1 billion in annual economic loss in species that utilize this forage resource. Approximately 90% of tall fescue contains an endophytic fungus (Epichloë coenophiala) that produces ergot alkaloids. Ergot alkaloids cause vasoconstriction and reduced blood flow to the extremities, however it remains unknown how blood flow to the reproductive organs is affected in cattle...
August 9, 2018: Journal of Animal Science
Shohei Kawachi, Keisaku Fujimoto
Objective This study was performed to determine the usefulness of a newly developed spirometer for the quantitative assessment of dynamic lung hyperinflation (DLH) following incremental hyperventilation in chronic obstructive pulmonary disease (COPD). Methods The subjects were 54 patients with COPD and 25 healthy volunteers. Each subject was asked to hyperventilate for 30 s with stepwise increments starting at the resting respiration rate and increasing to respiratory rates of 20, 30, and finally 40 breaths/min while using a newly developed spirometer...
August 10, 2018: Internal Medicine
David P Looney, William R Santee, Laurie A Blanchard, Anthony J Karis, Alyssa J Carter, Adam W Potter
This study examined complex terrain march performance and cardiorespiratory responses when carrying different Soldier loads. Nine active duty military personnel (age, 21 ± 3 yr; height, 1.72 ± 0.07 m; body mass (BM), 83.4 ± 12.9 kg) attended two test visits during which they completed consecutive laps around a 2.5-km mixed terrain course with either a fighting load (30% BM) or an approach load (45% BM). Respiratory rate and heart rate data were collected using physiological status monitors. Training impulse (TRIMP) scores were calculated using Banister's formula to provide an integrated measure of both time and cardiorespiratory demands...
November 2018: Applied Ergonomics
Lexandra Schick, Brian Driver, Johanna C Moore, Erik Fagerstrom, James R Miner
OBJECTIVES: To determine if there is a difference in procedural amnesia and adverse respiratory events (ARE) between the target sedation levels of moderate (MS) and deep (DS) procedural sedation. METHODS: This was a prospective, randomized clinical trial of consenting adult patients planning to undergo deep procedural sedation with propofol between March 5th , 2015 and May 24th , 2017. Patients were randomized to a target sedation level of moderate or deep sedation using the American Society of Anesthesiologist's definitions...
August 11, 2018: Academic Emergency Medicine: Official Journal of the Society for Academic Emergency Medicine
Yujie Su, Huifeng Li, Chang Xu, Xiaodan Wang, Jia Xie, Jian G Qin, Liqiao Chen, Erchao Li
DCOIT (4,5-dichloro-2-n-octyl-4-isothiazolin-3-one) is the main active ingredient in an emerging water environment antifoulant, the toxicity and environmental impacts of which need to be further investigated. Thus, this study examined the toxicity of DCOIT on Nile tilapia (Oreochromis niloticus), including its effects on behavior, respiration and energy metabolism as well as the role of endoplasmic reticulum stress (ER stress) in mediating its toxicity and metabolic changes. The changes in fish behavior, respiration, neuronal signal transmission, energy metabolism, ER stress, and liver histology were examined via acute (4 days) and chronic (28 days) exposures to 0, 3, 15, 30 μg/L DCOIT in vivo...
July 11, 2018: Environmental Pollution
Salwan Al-Maliki, Mugtaba Al-Masoudi
Soil salinity has an adverse impact on soil biological properties and growth of corn plant, majorly in arid and semi-arid lands. A mesocosm experiment was conducted to investigate the effect of mycorrhizal fungi (M) ( Glomus mosseae ), tea wastes (T), algal dried biomass (A), and their combinations on soil respiration, total bacteria, total fungi, soil mean weight diameter (MWD), and corn yield ( Zea mays L.) . under saline and non-saline soils. Results showed that M, T, and A treatments increased significantly CO₂ release compared to the control...
August 8, 2018: Plants (Basel, Switzerland)
Taekhee Lee, Andrew Thorpe, Emanuele Cauda, Leah Tipton, Wayne T Sanderson, Alan Echt
A newly developed high flow rate respirable size-selective cyclone sampler (GK4.162-also known as the Respirable Air Sampling Cyclone Aluminum Large (RASCAL)) was calibrated to determine its optimum operating flow rate. The Health and Safety Laboratory in the United Kingdom and two laboratories from the National Institute for Occupational Safety and Health in the United States conducted experiments using two different methods: (1) polydisperse aerosol and time-of-flight direct reading instrument (Aerodynamic Particle Sizer (APS)) and (2) monodisperse aerosol and APS...
August 10, 2018: Journal of Occupational and Environmental Hygiene
Adrien Jacotot, Cyril Marchand, Simon Gensous, Michel Allenbach
In this study, we examined interactive effects of elevated atmospheric CO2 , concentrations, and increased tidal flooding on two mangroves species, Avicennia marina and Rhizophora stylosa. Leaf gas-exchange parameters (photosynthesis, transpiration rates, water-use efficiency, stomatal conductance, and dark respiration rates) were measured monthly on more than 1000 two-year-old seedlings grown in greenhouses for 1 year. In addition, stomatal density and light curve responses were determined at the end of the experiment...
August 9, 2018: Photosynthesis Research
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"