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https://www.readbyqxmd.com/read/28212018/derivation-of-hydroperoxyl-radical-ho2-levels-at-an-urban-site-via-measurement-of-pernitric-acid-ho2no2-by-iodide-chemical-ionization-mass-spectrometry-i-cims
#1
Dexian Chen, L Gregory Huey, David J Tanner, Jianfeng Li, Nga Lee Ng, Yuhang Wang
Hydroperoxyl radical (HO2) is a key species to atmospheric chemistry. At warm temperatures, the hydroperoxyl radical (HO2) and NO2 come to a rapid steady state with pernitric acid (HO2NO2). This paper presents the derivation of HO2 from observations of HO2NO2 and NO2 in metropolitan Atlanta, US in winter 2014 and summer 2015. HO2 was observed to have a diurnal cycle with morning concentrations suppressed by high NO from the traffic. At night, derived HO2 levels were nonzero and exhibited correlations with O3 and NO3, consistent with previous studies that ozonolysis and oxidation by NO3 are sources of nighttime HO2...
February 17, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28209805/effects-of-photophase-illuminance-on-locomotor-activity-urine-production-and-urinary-6-sulfatoxymelatonin-in-nocturnal-and-diurnal-south-african-rodents
#2
Ingrid van der Merwe, Maria K Oosthuizen, Andre Ganswindt, Abraham Haim, Nigel C Bennett
Effects of photophase illuminance (1, 10, 100 and 330 lux of white incandescent lighting) on daily rhythms of locomotor activity, urine production and 6-sulfatoxymelatonin (6-SMT; 10 lux vs. 330 lux) were studied in nocturnal Namaqua rock mice (Micaelamys namaquensis) and diurnal four striped field mice (Rhabdomys pumilio). Micaelamys namaquensis was consistently nocturnal (∼90-94% nocturnal activity), whereas considerable individual variation marked activity profiles in R. pumilio, but with activity mostly pronounced around twilight (∼55-66% diurnal activity)...
February 16, 2017: Journal of Experimental Biology
https://www.readbyqxmd.com/read/28209543/hpa-axis-and-inflammatory-reactivity-to-acute-stress-is-related-with-basal-hpa-axis-activity
#3
Xuejie Chen, Danielle Gianferante, Luke Hanlin, Alexander Fiksdal, Juliana G Breines, Myriam V Thoma, Nicolas Rohleder
INTRODUCTION: Inflammation is drawing attention as pathway between psychosocial stress and health, and basal HPA axis activity has been suggested to exert a consistent regulatory influence on peripheral inflammation. Here we studied the relationship between basal HPA axis activity and inflammatory and HPA axis acute stress reactivity. METHODS: We recruited 48 healthy individuals and collected saliva for diurnal cortisol sampling at 6 points. Participants were previously exposed to the Trier Social Stress Test (TSST) on two consecutive days...
February 6, 2017: Psychoneuroendocrinology
https://www.readbyqxmd.com/read/28209509/the-raptor-visual-system-an-update
#4
J González-Martín-Moro, J L Hernández-Verdejo, A Clement-Corral
OBJECTIVE: Diurnal birds of prey (raptors) are considered the group of animals with highest visual acuity (VA). The purpose of this work is to review all the information recently published about the visual system of this group of animals. MATERIAL AND METHODS: A bibliographic search was performed in PubMed. The algorithm used was (raptor OR falcon OR kestrel OR hawk OR eagle) AND (vision OR «visual acuity» OR eye OR macula OR retina OR fovea OR «nictitating membrane» OR «chromatic vision» OR ultraviolet)...
February 13, 2017: Archivos de la Sociedad Española de Oftalmología
https://www.readbyqxmd.com/read/28209308/melatonin-and-cortisol-secretion-profile-in-patients-with-pineal-cyst-before-and-after-pineal-cyst-resection
#5
Martin Májovský, David Netuka, Ondřej Bradáč, Vladimír Beneš
A pineal cyst is a benign affection of the human pineal gland on the borderline between pathology and normality. Only a small percentage of patients present with symptoms and a surgical treatment is indicated in highly selected cases. A melatonin secretion in patients with a pineal cyst before and after a pineal cyst resection has not been studied yet and the effect of surgery on human metabolism is unknown. The present study examined melatonin, cortisol and blood glucose secretion profiles perioperatively in a surgical group of 4 patients...
February 10, 2017: Journal of Clinical Neuroscience: Official Journal of the Neurosurgical Society of Australasia
https://www.readbyqxmd.com/read/28206710/sucrose-transporter2-contributes-to-maize-growth-development-and-crop-yield
#6
Kristen A Leach, Thu M Tran, Thomas L Slewinski, Robert B Meeley, David M Braun
During daylight, plants produce excess photosynthates, including sucrose, which is temporarily stored in the vacuole. At night, plants remobilize sucrose to sustain metabolism and growth. Based on homology to other sucrose transporter (SUT) proteins, we hypothesized the maize (Zea mays) SUCROSE TRANSPORTER2 (ZmSUT2) protein functions as a sucrose/H(+) symporter on the vacuolar membrane to export transiently stored sucrose. To understand the biological role of ZmSut2, we examined its spatial and temporal gene expression, determined the protein subcellular localization, and characterized loss-of-function mutations...
February 16, 2017: Journal of Integrative Plant Biology
https://www.readbyqxmd.com/read/28202701/chronobiology-differs-between-men-and-women-with-cluster-headache-clinical-phenotype-does-not
#7
Nunu Lund, Mads Barloese, Anja Petersen, Bryan Haddock, Rigmor Jensen
OBJECTIVE: To describe differences between the sexes in the phenotype of cluster headache (CH) in a large, well-characterized clinical CH population. METHODS: Patients from the Danish CH survey aged 18-65 years, diagnosed with CH according to International Classification of Headache Disorders, second edition, completed questionnaires and structured interviews. RESULTS: A total of 351 patients with CH participated, with a male:female ratio of 2:1...
February 15, 2017: Neurology
https://www.readbyqxmd.com/read/28202598/early-flowering-3-redundancy-fine-tunes-photoperiod-sensitivity
#8
Andrew J S Rubenach, Valerie Fg Hecht, Jacqueline K Vander Schoor, Lim Chee Liew, Gregoire Aubert, Judith Burstin, James L Weller
Three pea loci controlling photoperiod sensitivity, HIGH RESPONSE (HR), DIE NEUTRALIS (DNE) and STERILE NODES (SN) have recently been shown to correspond to orthologs of Arabidopsis circadian clock genes EARLY FLOWERING3 (ELF3), ELF4, and LUX ARRHYTHMO, respectively. A fourth pea locus, PHOTOPERIOD (PPD), also contributes to the photoperiod response in a similar manner to SN and DNE, and recessive ppd mutants on a spring-flowering hr mutant background show early, photoperiod-insensitive flowering. However, the molecular identity of PPD has so far remained elusive...
February 15, 2017: Plant Physiology
https://www.readbyqxmd.com/read/28202268/three-dimensional-investigation-of-ozone-pollution-in-the-lower-troposphere-using-an-unmanned-aerial-vehicle-platform
#9
Xiao-Bing Li, Dong-Sheng Wang, Qing-Chang Lu, Zhong-Ren Peng, Si-Jia Lu, Bai Li, Chao Li
Potential utilities of instrumented lightweight unmanned aerial vehicles (UAVs) to quickly characterize tropospheric ozone pollution and meteorological factors including air temperature and relative humidity at three-dimensional scales are highlighted in this study. Both vertical and horizontal variations of ozone within the 1000 m lower troposphere at a local area of 4 × 4 km(2) are investigated during summer and autumn times. Results from field measurements show that the UAV platform has a sufficient reliability and precision in capturing spatiotemporal variations of ozone and meteorological factors...
February 12, 2017: Environmental Pollution
https://www.readbyqxmd.com/read/28202252/what-worries-parents-of-a-child-with-autism-evidence-from-a-biomarker-for-chronic-stress
#10
Vicki Bitsika, Christopher F Sharpley, Nicholas M Andronicos, Linda L Agnew
BACKGROUND: Previous studies have reported correlations between various aspects of the behaviour and symptomatology of children with Autism Spectrum Disorder (ASD) and their parents' self-reports of stress via standardised scales. AIMS: To extend that literature, a physiological index of parental chronic stress was used instead of their self-reports-dysregulation of the Diurnal Rhythm (DR) of the Hypothalamic-Pituitary-Adrenal (HPA) axis. METHODS: A sample of 149 parents of a child with ASD provided salivary cortisol at the predicted time of daily maximum cortisol concentration and at a time of daily lower concentration...
February 12, 2017: Research in Developmental Disabilities
https://www.readbyqxmd.com/read/28202094/impact-of-routine-bacillus-thuringiensis-israelensis-bti-treatment-on-the-availability-of-flying-insects-as-prey-for-aerial-feeding-predators
#11
Ute Timmermann, Norbert Becker
Since 1980, mosquito breeding habitats in the Upper Rhine Valley were routinely treated with Bacillus thuringiensis var. israelensis (Bti). Bti is considered to significantly reduce the number of mosquitoes, and - especially when used in higher dosages - to be toxic to other Nematocera species, e.g. Chironomidae, which could be food sources for aerial feeding predators. To investigate direct and indirect effects of routine Bti treatment on food sources for aerial feeding predators, the availability of flying insects in treated and untreated areas was compared...
February 16, 2017: Bulletin of Entomological Research
https://www.readbyqxmd.com/read/28199858/associations-between-hippocampal-morphology-diffusion-characteristics-and-salivary-cortisol-in-older-men
#12
Simon R Cox, Maria Del Carmen Valdés Hernández, Jaeil Kim, Natalie A Royle, Sarah E MacPherson, Karen J Ferguson, Susana Muñoz Maniega, Devasuda Anblagan, Benjamin S Aribisala, Mark E Bastin, Jinah Park, John M Starr, Ian J Deary, Alasdair M J MacLullich, Joanna M Wardlaw
High, unabated glucocorticoid (GC) levels are thought to selectively damage certain tissue types. The hippocampus is thought to be particularly susceptible to such effects, and though findings from animal models and human patients provide some support for this hypothesis, evidence for associations between elevated GCs and lower hippocampal volumes in older age (when GC levels are at greater risk of dysregulation) is inconclusive. To address the possibility that the effects of GCs in non-pathological ageing may be too subtle for gross volumetry to reliably detect, we analyse associations between salivary cortisol (diurnal and reactive measures), hippocampal morphology and diffusion characteristics in 88 males, aged ∼73 years...
January 27, 2017: Psychoneuroendocrinology
https://www.readbyqxmd.com/read/28196342/decreased-salivary-alpha-amylase-levels-are-associated-with-performance-deficits-during-sleep-loss
#13
Maja Pajcin, Siobhan Banks, Jason M White, Jill Dorrian, Gemma M Paech, Crystal Grant, Kayla Johnson, Katie Tooley, Justin Fidock, Gary H Kamimori, Chris B Della Vedova
During sleep deprivation, neurobehavioral functions requiring sustained levels of attention and alertness are significantly impaired. Discrepancies between subjective measures of sleepiness and objective performance during sustained operations have led to interest in physiological monitoring of operator performance. Alertness, vigilance, and arousal are modulated by the wake-promoting actions of the central noradrenergic system. Salivary alpha-amylase (sAA) has been proposed as a sensitive peripheral measure of noradrenergic activity, but limited research has investigated the relationship between sAA and performance...
February 1, 2017: Psychoneuroendocrinology
https://www.readbyqxmd.com/read/28195849/detection-and-alterations-of-acetylcarnitine-in-human-skeletal-muscles-by-1h-mrs-at-7-t
#14
Radka Klepochová, Ladislav Valkovič, Martin Gajdošík, Thomas Hochwartner, Harald Tschan, Michael Krebs, Siegfried Trattnig, Martin Krššák
OBJECTIVES: The aims of this study were to detect the acetylcarnitine resonance line at 2.13 ppm in the human vastus lateralis and soleus muscles, assess T1 and T2 relaxation times, and investigate the diurnal and exercise-related changes in absolute concentration noninvasively, using proton magnetic resonance spectroscopy at 7 T. MATERIALS AND METHODS: All measurements were performed on a 7 T whole-body Magnetom MR system with a 28-channel knee coil. Five healthy, moderately trained volunteers participated in the assessment of the detectability, repeatability, and relaxation times of acetylcarnitine...
February 10, 2017: Investigative Radiology
https://www.readbyqxmd.com/read/28194652/hair-cortisol-in-the-evaluation-of-cushing-syndrome
#15
Aaron Hodes, Maya B Lodish, Amit Tirosh, Jerrold Meyer, Elena Belyavskaya, Charalampos Lyssikatos, Kendra Rosenberg, Andrew Demidowich, Jeremy Swan, Nichole Jonas, Constantine A Stratakis, Mihail Zilbermint
PURPOSE: Hair cortisol evaluation has been used to help detect patients with suspected Cushing syndrome. Our goal was to correlate segmental hair cortisol with biochemical testing in patients with Cushing syndrome and controls. This study was a prospective analysis of hair cortisol in confirmed Cushing syndrome cases over 16 months. METHODS: Thirty-six subjects (26.5 ± 18.9 years, 75% female, and 75% Caucasian) were analyzed by diurnal serum cortisol, 24 h urinary free cortisol corrected for body surface area (UFC/BSA), and 24 h urinary 17-hydroxysteroids corrected for creatinine (17OHS/Cr)...
February 13, 2017: Endocrine
https://www.readbyqxmd.com/read/28193809/living-in-the-dark-does-not-mean-a-blind-life-bird-and-mammal-visual-communication-in-dim-light
#16
REVIEW
Vincenzo Penteriani, María Del Mar Delgado
For many years, it was believed that bird and mammal communication 'in the dark of the night' relied exclusively on vocal and chemical signalling. However, in recent decades, several case studies have conveyed the idea that the nocturnal world is rich in visual information. Clearly, a visual signal needs a source of light to work, but diurnal light (twilight included, i.e. any light directly dependent on the sun) is not the only source of luminosity on this planet. Actually, moonlight represents a powerful source of illumination that cannot be neglected from the perspective of visual communication...
April 5, 2017: Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
https://www.readbyqxmd.com/read/28192775/intraindividual-variability-in-cortisol-approaches-illustrations-and-recommendations
#17
REVIEW
Suzanne C Segerstrom, Sandra E Sephton, Philip M Westgate
Most of the variance in diurnal cortisol is attributable to intraindividual variability (IIV), defined as relatively short-term, reversible changes. Multiple methods for measuring IIV have been proposed, and some have already been applied to cortisol IIV. In the present review, measurement methods are described and applied to simulated cortisol data with known underlying differences in IIV and to real cortisol data from first-year law students. More slope variance and more residual or net variance were well captured by their individual standard deviations...
January 28, 2017: Psychoneuroendocrinology
https://www.readbyqxmd.com/read/28192738/temporal-variations-in-water-quality-in-a-brackish-tidal-pond-implications-for-governing-processes-and-management-strategies
#18
Wenhui Cui, Ting Fong May Chui
Brackish tidal ponds have been constructed along coastal areas in many parts of the world for aquaculture, including some Ramsar Sites. Such ponds are considered a sustainable, wise use of wetlands if managed properly, but they can also pose serious environmental problems if mismanaged. To understand the governing processes and to promote sustainable management strategies, this study examines the different temporal variations in water quality parameters in a brackish tidal pond located within the wetland complex of the Mai Po Ramsar Site in Hong Kong, China...
February 10, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28188549/characteristics-and-source-apportionment-of-black-carbon-aerosols-over-an-urban-site
#19
T A Rajesh, S Ramachandran
Aethalometer based source apportionment model using the measured aerosol absorption coefficients at different wavelengths is used to apportion the contribution of fossil fuel and wood burning sources to the total black carbon (BC) mass concentration. Temporal and seasonal variabilities in BC mass concentrations, equivalent BC from fossil fuel (BC f f ), and wood burning (BC w b ) are investigated over an urban location in western India during January 2014 to December 2015. BC, BC f f , and BC w b mass concentrations exhibit strong diurnal variation and are mainly influenced by atmospheric dynamics...
February 10, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28188231/diurnal-and-long-term-variation-in-plasma-concentrations-and-renal-clearances-of-circulating-markers-of-kidney-proximal-tubular-secretion
#20
Matthew B Rivara, Leila R Zelnick, Andrew N Hoofnagle, Rick Newitt, Russell P Tracy, Mario Kratz, David S Weigle, Bryan R Kestenbaum
BACKGROUND: The renal proximal tubule is essential for removing organic solutes and exogenous medications from the circulation. We evaluated diurnal, prandial, and long-term biological variation of 4 candidate endogenous markers of proximal tubular secretion. METHODS: We used LC-MS to measure plasma and urine concentrations of hippurate (HA), cinnamoylglycine (CMG), indoxyl sulfate (IS), and p-cresol sulfate (PCS) in 25 healthy adults. We measured plasma concentrations of secreted solutes at 13 time points over a 24-h period, and again after 2 weeks and 14 weeks of follow-up...
February 10, 2017: Clinical Chemistry
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