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https://www.readbyqxmd.com/read/29468029/patterns-of-activity-and-body-temperature-of-aldabra-giant-tortoises-in-relation-to-environmental-temperature
#1
Wilfredo Falcón, Rich P Baxter, Samuel Furrer, Martin Bauert, Jean-Michel Hatt, Gabriela Schaepman-Strub, Arpat Ozgul, Nancy Bunbury, Marcus Clauss, Dennis M Hansen
We studied the temperature relations of wild and zoo Aldabra giant tortoises ( Aldabrachelys gigantea ) focusing on (1) the relationship between environmental temperature and tortoise activity patterns ( n  = 8 wild individuals) and (2) on tortoise body temperature fluctuations, including how their core and external body temperatures vary in relation to different environmental temperature ranges (seasons; n  = 4 wild and n  = 5 zoo individuals). In addition, we surveyed the literature to review the effect of body mass on core body temperature range in relation to environmental temperature in the Testudinidae...
February 2018: Ecology and Evolution
https://www.readbyqxmd.com/read/29467050/does-the-diurnal-pattern-of-enteric-methane-emissions-from-dairy-cows-change-over-time
#2
M J Bell, J Craigon, N Saunders, J R Goodman, P C Garnsworthy
Diet manipulation and genetic selection are two important mitigation strategies for reducing enteric methane (CH4) emissions from ruminant livestock. The aim of this study was to assess whether the diurnal pattern of CH4 emissions from individual dairy cows changes over time when cows are fed on diets varying in forage composition. Emissions of CH4 from 36 cows were measured during milking in an automatic (robotic) milking station in three consecutive feeding periods, for a total of 84 days. In Periods 1 and 2, the 36 cows were fed a high-forage partial mixed ration (PMR) containing 75% forage, with either a high grass silage or high maize silage content...
February 22, 2018: Animal: An International Journal of Animal Bioscience
https://www.readbyqxmd.com/read/29467028/diurnal-variation-of-nmda-receptor-expression-in-the-rat-cerebral-cortex-is-associated-with-traumatic-brain-injury-damage
#3
Francisco Estrada-Rojo, Julio Morales-Gomez, Elvia Coballase-Urrutia, Marina Martinez-Vargas, Luz Navarro
OBJECTIVE: Data from our laboratory suggest that recovery from a traumatic brain injury depends on the time of day at which it occurred. In this study, we examined whether traumatic brain injury -induced damage is related to circadian variation in N-methyl-D-aspartate receptor expression in rat cortex. RESULTS: We confirmed that traumatic brain injury recovery depended on the time of day at which the damage occurred. We also found that motor cortex N-methyl-D-aspartate receptor subunit NR1 expression exhibited diurnal variation in both control and traumatic brain injury-subjected rats...
February 21, 2018: BMC Research Notes
https://www.readbyqxmd.com/read/29463317/adherence-to-the-face-down-positioning-after-vitrectomy-and-gas-tamponade-a-time-series-analysis
#4
Keita Suzuki, Yoshiaki Shimada, Yui Seno, Tadashi Mizuguchi, Atsuhiro Tanikawa, Masayuki Horiguchi
OBJECTIVE: To determine the adherence to the face-down positioning (FDP) in 296 patients who had undergone vitrectomy and gas tamponade. RESULTS: We studied 119 female and 177 male patients who had undergone primary vitrectomy and gas tamponade for a macular hole (MH) or for rhegmatogenous retinal detachments (RRDs). Adherence was assessed and recorded four times per day for 3 days postsurgery. The mean ± standard deviation adherence rate was 88.3 ± 11.7 (range 50...
February 20, 2018: BMC Research Notes
https://www.readbyqxmd.com/read/29462016/diurnal-variations-of-peripapillary-and-macular-vessel-density-in-glaucomatous-eyes-using-ocular-coherence-tomography-angiography
#5
Kaweh Mansouri, Harsha L Rao, Kirsten Hoskens, Elisa D'Alessandro, Elsa M Flores-Reyes, André Mermoud, Robert N Weinreb
PURPOSE: To investigate the diurnal variation in peripapillary and macular vessel density (VD) measurements using optical coherence tomography angiography (OCT-A) and its correlation to intraocular pressure (IOP) changes in glaucoma patients. METHODS: Prospective, observational cross-sectional study including 37 patients (74 eyes; age, 63.8±12.9▒y) with open angle glaucoma. OCT-A imaging and IOP measurements were performed at 08:00, 11:00, 14:00, and 16:00 on a single day...
February 16, 2018: Journal of Glaucoma
https://www.readbyqxmd.com/read/29456171/a-magnetic-resonance-imaging-framework-for-quantifying-intervertebral-disc-deformation-in-vivo-reliability-and-application-to-diurnal-variations-in-lumbar-disc-shape
#6
John T Martin, Alexander B Oldweiler, Charles E Spritzer, Brian J Soher, Melissa M Erickson, Adam P Goode, Louis E DeFrate
Low back pain is a significant socioeconomic burden in the United States and lumbar intervertebral disc degeneration is frequently implicated as a cause. The discs play an important mechanical role in the spine, yet the relationship between disc function and back pain is poorly defined. The objective of this work was to develop a technique using magnetic resonance imaging (MRI) and three-dimensional modeling to measure in vivo disc deformations. Using this method, we found that disc geometry was measurable with precision less than the in-plane dimensions of a voxel (≈100 µm, 10% of the MRI pixel size)...
February 9, 2018: Journal of Biomechanics
https://www.readbyqxmd.com/read/29454168/genetic-and-environmental-influences-on-pubertal-hormones-in-human-hair-across-development
#7
Andrew D Grotzinger, Daniel A Briley, Laura E Engelhardt, Frank D Mann, Megan W Patterson, Jennifer L Tackett, Elliot M Tucker-Drob, K Paige Harden
Puberty is a complex biopsychosocial process that can affect an array of psychiatric and medical disorders emerging in adolescence. Although the pubertal process is driven by neuroendocrine changes, few quantitative genetic studies have directly measured puberty-relevant hormones. Hair samples can now be assayed for accumulation of hormones over several months. In contrast to more conventional salivary measures, hair measures are not confounded by diurnal variation or hormonal reactivity. In an ethnically and socioeconomically diverse sample of 1286 child and adolescent twins and multiples from 672 unique families, we estimated genetic and environmental influences on hair concentrations of testosterone, DHEA, and progesterone across the period of 8-18 years of age...
February 12, 2018: Psychoneuroendocrinology
https://www.readbyqxmd.com/read/29448046/diurnal-variation-in-admission-troponin-concentrations-in-patients-with-chest-pain-in-the-emergency-department
#8
Andreas Roos, Martin J Holzmann
BACKGROUND: Recent studies have suggested that there may be large diurnal variation in cardiac troponin T (cTnT) concentrations measured with a high sensitive assay. OBJECTIVE: To investigate if clinically relevant diurnal variation in cTnT concentrations is present in patients with chest pain in the emergency department (ED). METHODS: We included all patients with chest pain, but no myocardial infarction (MI), and no other acute condition that may affect troponin concentrations in the ED at Karolinska University Hospital, Stockholm, Sweden, 2011-2014...
February 12, 2018: Clinical Biochemistry
https://www.readbyqxmd.com/read/29448026/characterization-and-source-identification-of-fine-particulate-matter-in-urban-beijing-during-the-2015-spring-festival
#9
Dongsheng Ji, Yang Cui, Liang Li, Jun He, Lili Wang, Hongliang Zhang, Wan Wang, Luxi Zhou, Willy Maenhaut, Tianxue Wen, Yuesi Wang
The Spring Festival (SF) is the most important holiday in China for family reunion and tourism. During the 2015 SF an intensive observation campaign of air quality was conducted to study the impact of the anthropogenic activities and the dynamic characteristics of the sources. During the study period, pollution episodes frequently occurred with 12days exceeding the Chinese Ambient Air Quality Standards for 24-h average PM 2.5 (75μg/m 3 ), even 8days with exceeding 150μg/m 3 . The daily maximum PM 2.5 concentration reached 350μg/m 3 while the hourly minimum visibility was <0...
February 12, 2018: Science of the Total Environment
https://www.readbyqxmd.com/read/29444421/chloroplast-signaling-gates-thermotolerance-in-arabidopsis
#10
Patrick J Dickinson, Manoj Kumar, Claudia Martinho, Seong Jeon Yoo, Hui Lan, George Artavanis, Varodom Charoensawan, Mark Aurel Schöttler, Ralph Bock, Katja E Jaeger, Philip A Wigge
Temperature is a key environmental variable influencing plant growth and survival. Protection against high temperature stress in eukaryotes is coordinated by heat shock factors (HSFs), transcription factors that activate the expression of protective chaperones such as HEAT SHOCK PROTEIN 70 (HSP70); however, the pathway by which temperature is sensed and integrated with other environmental signals into adaptive responses is not well understood. Plants are exposed to considerable diurnal variation in temperature, and we have found that there is diurnal variation in thermotolerance in Arabidopsis thaliana, with maximal thermotolerance coinciding with higher HSP70 expression during the day...
February 13, 2018: Cell Reports
https://www.readbyqxmd.com/read/29428294/role-of-light-and-the-circadian-clock-in-the-rhythmic-oscillation-of-intraocular-pressure-studies-in-vpac2-receptor-and-pacap-deficient-mice
#11
Jan Fahrenkrug, Birgitte Georg, Jens Hannibal, Henrik Løvendahl Jørgensen
The intraocular pressure of mice displays a daily rhythmicity being highest during the dark period. The present study was performed to elucidate the role of the circadian clock and light in the diurnal and the circadian variations in intraocular pressure in mice, by using animals with disrupted clock function (VPAC2 receptor knockout mice) or impaired light information to the clock (PACAP knockout mice). In wildtype mice, intraocular pressure measured under light/dark conditions showed a statistically significant 24 h sinusoidal rhythm with nadir during the light phase and peak during the dark phase...
February 8, 2018: Experimental Eye Research
https://www.readbyqxmd.com/read/29425573/diurnal-variation-of-default-mode-network-in-patients-with-restless-legs-syndrome
#12
Jeonghun Ku, Yeong Seon Lee, Hyuk Won Chang, Christopher J Earley, Richard P Allen, Yong Won Cho
OBJECTIVE: Restless legs syndrome (RLS) patients compared to controls have been found to have abnormal patterns in the default mode network (DMN) in the morning when symptom threshold is the highest and symptoms are least likely to occur. If these morning abnormalities in DMN are pertinent to disease expression, then similar or further detectable differences may be expected on a nighttime assessment when RLS symptom threshold is at its lowest. The purpose of this study was to elucidate the potential neural mechanisms underlying the circadian aspect of RLS symptom expression by assessing diurnal changes in DMN...
January 2018: Sleep Medicine
https://www.readbyqxmd.com/read/29423533/biologically-validating-the-measurement-of-oxytocin-in-western-lowland-gorilla-gorilla-gorilla-gorilla-urine-and-saliva-using-a-commercial-enzyme-immunoassay
#13
Austin Leeds, Patricia M Dennis, Kristen E Lukas, Tara S Stoinski, Mark A Willis, Mandi W Schook
The neuroendocrine hormone oxytocin, which is an important physiological driver of social behavior and bonding, is increasingly being measured in conjunction with behavior to better understand primate sociality. However, no data are available on oxytocin concentrations within the genus Gorilla, even though the members of this genus are of great interest to researchers due to their close genetic relatedness to humans and their tolerance-based social system. The purpose of this study was to validate the measurement of urinary and salivary oxytocin in western lowland gorillas (Gorilla gorilla gorilla) to facilitate future study of the interaction between oxytocin and behavior in this subspecies...
February 8, 2018: Primates; Journal of Primatology
https://www.readbyqxmd.com/read/29415552/eveningness-is-associated-with-poor-sleep-quality-and-negative-affect-in-obsessive-compulsive-disorder
#14
Péter Simor, András Harsányi, Kata Csigó, Gergely Miklós, Alpár Sándor Lázár, Gyula Demeter
Background Obsessive-compulsive disorder (OCD) is characterized by intrusive thoughts and repetitive behaviors that severely encumber daily functioning. OCD patients seem to exhibit sleep disturbances, especially delayed bedtimes that reflect disrupted circadian rhythmicity. Morningness-eveningness is a fundamental factor reflecting individual variations in diurnal preferences related to sleep and waking activities. Eveningness reflecting a delayed sleep-wake timing has repeatedly been associated with sleep problems and negative affect (NA)...
February 8, 2018: Journal of Behavioral Addictions
https://www.readbyqxmd.com/read/29415039/discovery-of-a-diverse-cave-flora-in-china
#15
Alexandre K Monro, Nadia Bystriakova, Longfei Fu, Fang Wen, Yigang Wei
Few studies document plants in caves. Our field observations of a widespread and seemingly angiosperm-rich cave flora in SW China lead us to test the following hypotheses, 1) SW China caves contain a diverse vascular plant flora, 2) that this is a relic of a largely absent forest type lacking endemic species, and 3) that the light environment plants occupy in caves is not distinct from non-cave habitats. To do so we surveyed 61 caves and used species accumulation curves (SAC) to estimate the total diversity of this flora and used a subsample of 14 caves to characterise the light environment...
2018: PloS One
https://www.readbyqxmd.com/read/29401953/diurnal-variations-of-the-optical-properties-of-phytoplankton-in-a-laboratory-experiment-and-their-implication-for-using-inherent-optical-properties-to-measure-biomass
#16
Carina Poulin, David Antoine, Yannick Huot
Diurnal variations of phytoplankton size distributions, chlorophyll, carbon and nitrogen content, in vivo fluorescence and associated optical absorption and scattering properties were observed in the laboratory to help understand in situ and spatial observations. We grew triplicate semi-continuous cultures of T. pseudonana, D. tertiolecta, P. tricornutum and E. huxleyi under a sinusoidal light regime. We observed diurnal variations in the particulate absorption (ap), scattering (bp), attenuation (cp), and backscattering coefficients (bbp), which correlate with carbon and Chl concentrations...
January 22, 2018: Optics Express
https://www.readbyqxmd.com/read/29382842/the-sr-protein-b52-srp55-regulates-splicing-of-the-period-thermosensitive-intron-and-mid-day-siesta-in-drosophila
#17
Zhichao Zhang, Weihuan Cao, Isaac Edery
Similar to many diurnal animals, Drosophila melanogaster exhibits a mid-day siesta that is more robust as temperature increases, an adaptive response that aims to minimize the deleterious effects from exposure to heat. This temperature-dependent plasticity in mid-day sleep levels is partly based on the thermal sensitive splicing of an intron in the 3' untranslated region (UTR) of the circadian clock gene termed period (per). In this study, we evaluated a possible role for the serine/arginine-rich (SR) splicing factors in the regulation of dmpi8 splicing efficiency and mid-day siesta...
January 30, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29382089/estimation-of-the-land-surface-temperature-over-the-tibetan-plateau-by-using-chinese-fy-2c-geostationary-satellite-data
#18
Yuanyuan Hu, Lei Zhong, Yaoming Ma, Mijun Zou, Kepiao Xu, Ziyu Huang, Lu Feng
During the process of land-atmosphere interaction, one of the essential parameters is the land surface temperature (LST). The LST has high temporal variability, especially in its diurnal cycle, which cannot be acquired by polar-orbiting satellites. Therefore, it is of great practical significance to retrieve LST data using geostationary satellites. According to the data of FengYun 2C (FY-2C) satellite and the measurements from the Enhanced Observing Period (CEOP) of the Asia-Australia Monsoon Project (CAMP) on the Tibetan Plateau (CAMP/Tibet), a regression approach was utilized in this research to optimize the split window algorithm (SWA)...
January 28, 2018: Sensors
https://www.readbyqxmd.com/read/29380943/evidence-of-oxygenic-phototrophy-in-ancient-phosphatic-stromatolites-from-the-paleoproterozoic-vindhyan-and-aravalli-supergroups-india
#19
T Sallstedt, S Bengtson, C Broman, P M Crill, D E Canfield
Fossil microbiotas are rare in the early rock record, limiting the type of ecological information extractable from ancient microbialites. In the absence of body fossils, emphasis may instead be given to microbially derived features, such as microbialite growth patterns, microbial mat morphologies, and the presence of fossilized gas bubbles in lithified mats. The metabolic affinity of micro-organisms associated with phosphatization may reveal important clues to the nature and accretion of apatite-rich microbialites...
January 30, 2018: Geobiology
https://www.readbyqxmd.com/read/29374207/variability-in-phase-and-amplitude-of-diurnal-rhythms-is-related-to-variation-of-mood-in-bipolar-and-borderline-personality-disorder
#20
O Carr, K E A Saunders, A Tsanas, A C Bilderbeck, N Palmius, J R Geddes, R Foster, G M Goodwin, M De Vos
Variable mood is an important feature of psychiatric disorders. However, its measurement and relationship to objective measureas of physiology and behaviour have rarely been studied. Smart-phones facilitate continuous personalized prospective monitoring of subjective experience and behavioural and physiological signals can be measured through wearable devices. Such passive data streams allow novel estimates of diurnal variability. Phase and amplitude of diurnal rhythms were quantified using new techniques that fitted sinusoids to heart rate (HR) and acceleration signals...
January 26, 2018: Scientific Reports
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