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https://www.readbyqxmd.com/read/28445533/influence-of-temperature-on-daily-locomotor-activity-in-the-crab-uca-pugilator
#1
Audrey M Mat, Gideon P Dunster, Valerio Sbragaglia, Jacopo Aguzzi, Horacio O de la Iglesia
Animals living in the intertidal zone are exposed to prominent temperature changes. To cope with the energetic demands of environmental thermal challenges, ectotherms rely mainly on behavioral responses, which may change depending on the time of the day and seasonally. Here, we analyze how temperature shapes crabs' behavior at 2 different times of the year and show that a transition from constant cold (13.5°C) to constant warm (17.5°C) water temperature leads to increased locomotor activity levels throughout the day in fiddler crabs (Uca pugilator) collected during the summer...
2017: PloS One
https://www.readbyqxmd.com/read/28437746/catalytic-reduction-of-4-nitrophenol-and-photo-inhibition-of-pseudomonas-aeruginosa-using-gold-nanoparticles-as-photocatalyst
#2
Shafiullah Khan, Wang Runguo, Kamran Tahir, Zhang Jichuan, Liqun Zhang
A simple, green method is described for the synthesis of Gold (Au) nanoparticles (NPs) using Cotoneaster horizontalis extract as a phyto-reducer and capping agent with superior photo inhibition activity against Pseudomonas aeruginosa. Different from the other methods used elevated temperatures for nanoparticles synthesis, the novelty of our method lies in its energy saving process and fast synthesis rates (~5min for AuNPs), and its potential to tune the nanoparticles size and afterward their catalytic activity...
April 13, 2017: Journal of Photochemistry and Photobiology. B, Biology
https://www.readbyqxmd.com/read/28435109/visible-light-inactivation-of-e-%C3%A2-coli-cytotoxicity-and-ros-determination-of-biochemically-capped-gold-nanoparticles
#3
Faheem Ullah Khan, Yongmei Chen, Naeem Ullah Khan, Aftab Ahmad, Kamran Tahir, Zia UlHaq Khan, Arif Ullah Khan, Shifa Ullah Khan, Muslim Raza, Pingyu Wan
The formation of metal nanoparticles is one of the most vast and intensifying research areas in favor of prospective applications for the advancement of new technologies. It is a well-founded, significant feature of green chemistry that making marvelous interconnection between nano-biotechnology and microbial biotechnology. In the present research, the aqueous extract of medicinally important plant Coptis Chinensis (in Chinese called "gold thread") was applied for the synthesis of gold nanoparticles (Au-NPs)...
April 20, 2017: Microbial Pathogenesis
https://www.readbyqxmd.com/read/28434813/rhythmic-expressed-clock-regulates-the-transcription-of-proliferating-cellular-nuclear-antigen-in-teleost-retina
#4
Hang Song, Defeng Wang, Felipe De Jesus Perez, Rongrong Xie, Zhipeng Liu, Chun-Chun Chen, Meijuan Yu, Liudi Yuan, Russell D Fernald, Sheng Zhao
Teleost fish continues to grow their eyes throughout life with the body size. In Astatotilapia burtoni, the fish retina increases by adding new retinal cells at the ciliary marginal zone (CMZ) and in the outer nuclear layer (ONL). Cell proliferation at both sites exhibits a daily rhythm in number of dividing cells. To understand how this diurnal rhythm of new cell production is controlled in retinal progenitor cells, we studied the transcription pattern of clock genes in retina, including clock1a, clock1b, bmal1a (brain and muscle ARNT-Like), and per1b (period1b)...
April 20, 2017: Experimental Eye Research
https://www.readbyqxmd.com/read/28383025/visual-acuity-of-the-honey-bee-retina-and-the-limits-for-feature-detection
#5
Elisa Rigosi, Steven D Wiederman, David C O'Carroll
Visual abilities of the honey bee have been studied for more than 100 years, recently revealing unexpectedly sophisticated cognitive skills rivalling those of vertebrates. However, the physiological limits of the honey bee eye have been largely unaddressed and only studied in an unnatural, dark state. Using a bright display and intracellular recordings, we here systematically investigated the angular sensitivity across the light adapted eye of honey bee foragers. Angular sensitivity is a measure of photoreceptor receptive field size and thus small values indicate higher visual acuity...
April 6, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28380964/determination-of-the-excitation-rate-of-quantum-dots-mediated-by-momentum-resolved-bloch-like-surface-plasmon-polaritons
#6
M Lin, Z L Cao, H C Ong
When light emitters are being placed in close proximity to a plasmonic system, not only the emission but also the excitation can be strongly enhanced and both yield the surface plasmon polariton (SPP) mediated fluorescence enhancement. Here, we combine the rate equation model and coupled mode theory to formulate the excitation rate of light emitters located on a periodic metallic array. The rate is expressed in terms of quantities that can be measured by angle- and polarization-resolved reflectivity and photoluminescence spectroscopy...
March 20, 2017: Optics Express
https://www.readbyqxmd.com/read/28363897/differentiation-of-germinal-center-b-cells-into-plasma-cells-is-initiated-by-high-affinity-antigen-and-completed-by-tfh-cells
#7
Nike J Kräutler, Dan Suan, Danyal Butt, Katherine Bourne, Jana R Hermes, Tyani D Chan, Christopher Sundling, Warren Kaplan, Peter Schofield, Jennifer Jackson, Antony Basten, Daniel Christ, Robert Brink
Plasma cells (PCs) derived from germinal centers (GCs) secrete the high-affinity antibodies required for long-term serological immunity. Nevertheless, the process whereby GC B cells differentiate into PCs is uncharacterized, and the mechanism underlying the selective PC differentiation of only high-affinity GC B cells remains unknown. In this study, we show that differentiation into PCs is induced among a discrete subset of high-affinity B cells residing within the light zone of the GC. Initiation of differentiation required signals delivered upon engagement with intact antigen...
March 31, 2017: Journal of Experimental Medicine
https://www.readbyqxmd.com/read/28351982/the-transcription-factor-foxo1-controls-germinal-center-b-cell-proliferation-in-response-to-t-cell-help
#8
Takeshi Inoue, Ryo Shinnakasu, Wataru Ise, Chie Kawai, Takeshi Egawa, Tomohiro Kurosaki
Germinal center (GC) B cells cycle between two states, the light zone (LZ) and the dark zone (DZ), and in the latter they proliferate and hypermutate their immunoglobulin genes. How this functional transition takes place is still controversial. In this study, we demonstrate that ablation of Foxo1 after GC development led to the loss of the DZ GC B cells and disruption of the GC architecture, which is consistent with recent studies. Mechanistically, even upon provision of adequate T cell help, Foxo1-deficient GC B cells showed less proliferative expansion than controls...
April 3, 2017: Journal of Experimental Medicine
https://www.readbyqxmd.com/read/28330765/hsp90-and-pcreb-alterations-are-linked-to-mancozeb-dependent-behavioral-and-neurodegenerative-effects-in-a-marine-teleost
#9
Merylin Zizza, Mariana Di Lorenzo, Vincenza Laforgia, Emilia Furia, Giovanni Sindona, Marcello Canonaco, Rosa Maria Facciolo
The pesticide mancozeb (mz) is recognized as a potent inducer of oxidative stress due to its ability to catalyze the production of reactive oxygen species plus inhibiting mitochondrial respiration thus becoming an environmental risk for neurodegenerative diseases. Despite numerous toxicological studies on mz have been directed to mammals, attention on marine fish is still lacking. Thus, it was our intention to evaluate neurobehavioral activities of ornate wrasses (Thalassoma pavo) exposed to 0.2mg/l of mz after a preliminary screening test (0...
May 15, 2017: Toxicology and Applied Pharmacology
https://www.readbyqxmd.com/read/28315647/a-device-that-allows-rodents-to-behaviorally-thermoregulate-when-housed-in-vivariums
#10
Christopher J Gordon, Earl T Puckett, Elizabeth S Repasky, Andrew F M Johnstone
Laboratories and vivariums typically are maintained at ambient temperatures of 20 to 24 °C, leading to cold stress in mice. When mice are inactive and sleeping during the light phase, their zone of thermoneutrality associated with a basal metabolic rate is 30 to 32 °C. If given a choice, mice will use thermoregulatory behavior to seek out thermoneutral temperatures during the light phase. The cold stress of a vivarium can be problematic to researchers requiring an animal model that is not stressed metabolically...
March 1, 2017: Journal of the American Association for Laboratory Animal Science: JAALAS
https://www.readbyqxmd.com/read/28263537/chronic-unpredictable-mild-stress-paradigm-in-male-wistar-rats-effect-on-anxiety-and-depressive-like-behavior
#11
Romana Koprdova, Eszter Bögi, Kristína Belovičová, Natália Sedláčková, Monika Okuliarová, Eduard Ujházy, Mojmír Mach
OBJECTIVES: There are several models of depression. Chronic unpredictable mild stress (CMS) appears to have the greatest validity, although it is often being criticized for low reliability. METHODS: Male Wistar/DV rats were used in this study to assess our modified 2-week model of CMS as a combination of psychosocial, physical and metabolic stressors and to compare the effect of acute administration of venlafaxine (VFX) and diazepam (DZP), either in stress or no stress conditions...
December 18, 2016: Neuro Endocrinology Letters
https://www.readbyqxmd.com/read/28261669/environmental-viral-genomes-shed-new-light-on-virus-host-interactions-in-the-ocean
#12
Yosuke Nishimura, Hiroyasu Watai, Takashi Honda, Tomoko Mihara, Kimiho Omae, Simon Roux, Romain Blanc-Mathieu, Keigo Yamamoto, Pascal Hingamp, Yoshihiko Sako, Matthew B Sullivan, Susumu Goto, Hiroyuki Ogata, Takashi Yoshida
Metagenomics has revealed the existence of numerous uncharacterized viral lineages, which are referred to as viral "dark matter." However, our knowledge regarding viral genomes is biased toward culturable viruses. In this study, we analyzed 1,600 (1,352 nonredundant) complete double-stranded DNA viral genomes (10 to 211 kb) assembled from 52 marine viromes. Together with 244 previously reported uncultured viral genomes, a genome-wide comparison delineated 617 genus-level operational taxonomic units (OTUs) for these environmental viral genomes (EVGs)...
March 2017: MSphere
https://www.readbyqxmd.com/read/28244020/air-travel-circadian-rhythms-hormones-and-autoimmunity
#13
REVIEW
J Torres-Ruiz, A Sulli, M Cutolo, Y Shoenfeld
Biological rhythms are fundamental for homeostasis and have recently been involved in the regulatory processes of various organs and systems. Circadian cycle proteins and hormones have a direct effect on the inflammatory response and have shown pro- or anti-inflammatory effects in animal models of autoimmune diseases. The cells of the immune system have their own circadian rhythm, and the light-dark cycle directly influences the inflammatory response. On the other hand, patients with autoimmune diseases characteristically have sleep disorders and fatigue, and in certain disease, such as rheumatoid arthritis (RA), a frank periodicity in the signs and symptoms is recognized...
February 27, 2017: Clinical Reviews in Allergy & Immunology
https://www.readbyqxmd.com/read/28194094/food-seeking-in-a-risky-environment-a-method-for-evaluating-risk-and-reward-value-in-food-seeking-and-consumption-in-mice
#14
Sarah H Lockie, Clare V McAuley, Sasha Rawlinson, Natalie Guiney, Zane B Andrews
Most studies that measure food intake in mice do so in the home cage environment. This necessarily means that mice do not engage in food seeking before consumption, a behavior that is ubiquitous in free-living animals. We modified and validated several commonly used anxiety tests to include a palatable food reward within the anxiogenic zone. This allowed us to assess risk-taking behavior in food seeking in mice in response to different metabolic stimuli. We modified the open field test and the light/dark box by placing palatable peanut butter chips within a designated food zone inside the anxiogenic zone of each apparatus...
2017: Frontiers in Neuroscience
https://www.readbyqxmd.com/read/28100031/impact-of-melatonin-receptor-signaling-on-zeitgeber-time-dependent-changes-in-cell-proliferation-and-apoptosis-in-the-adult-murine-hippocampus
#15
Michaela Fredrich, Mareike Hampel, Kay Seidel, Elmar Christ, Horst-Werner Korf
The hippocampus is subjected to diurnal/circadian rhythms on both the morphological and molecular levels. Certain aspects of cell proliferation in the adult hippocampus are regulated by melatonin and accompanied by apoptosis to ensure proper tissue maintenance and function. The present study investigated Zeitgeber time (ZT)-dependent changes in cell proliferation and apoptosis in the adult murine hippocampus and their regulation by melatonin receptor type1 and type2 (MT1/2)-mediated signaling. Adult melatonin-proficient C3H/HeN mice and melatonin-proficient (C3H/HeN) mice with targeted deletion of MT1/2 were adapted to a 12-h light, 12-h dark photoperiod and were sacrificed at ZT00, ZT06, ZT12, and ZT18...
May 2017: Hippocampus
https://www.readbyqxmd.com/read/28069242/comparison-of-sonochemiluminescence-images-using-image-analysis-techniques-and-identification-of-acoustic-pressure-fields-via-simulation
#16
T Joyce Tiong, Tissa Chandesa, Yeow Hong Yap
One common method to determine the existence of cavitational activity in power ultrasonics systems is by capturing images of sonoluminescence (SL) or sonochemiluminescence (SCL) in a dark environment. Conventionally, the light emitted from SL or SCL was detected based on the number of photons. Though this method is effective, it could not identify the sonochemical zones of an ultrasonic systems. SL/SCL images, on the other hand, enable identification of 'active' sonochemical zones. However, these images often provide just qualitative data as the harvesting of light intensity data from the images is tedious and require high resolution images...
May 2017: Ultrasonics Sonochemistry
https://www.readbyqxmd.com/read/28002271/reproducibility-and-reliability-of-optical-coherence-tomography-angiography-for-foveal-avascular-zone-evaluation-and-measurement-in-different-settings
#17
Carlo La Spina, Adriano Carnevali, Alessandro Marchese, Giuseppe Querques, Francesco Bandello
PURPOSE: Optical coherence tomography angiography (OCTA) allows delineating the foveal avascular zone (FAZ) easily and noninvasively. The present study aims to test reproducibility and reliability of FAZ evaluation by means of OCTA in different settings. METHODS: Twenty-four eyes of 24 normal subjects were investigated using AngioVue OCTA Imaging System. A series of OCTA acquisitions were taken both in basal and in different experimental settings after vasoactive stimuli...
December 20, 2016: Retina
https://www.readbyqxmd.com/read/27867253/drosophila-ezoana-uses-an-hour-glass-or-highly-damped-circadian-clock-for-measuring-night-length-and-inducing-diapause
#18
Koustubh M Vaze, Charlotte Helfrich-Förster
Insects inhabiting the temperate zones measure seasonal changes in day or night length to enter the overwintering diapause. Diapause induction occurs after the duration of the night exceeds a critical night length (CNL). Our understanding of the time measurement mechanisms is continuously evolving subsequent to Bünning's proposal that circadian systems play the clock role in photoperiodic time measurement (Bünning, 1936). Initially, the photoperiodic clocks were considered to be either based on circadian oscillators or on simple hour-glasses, depending on 'positive' or 'negative' responses in Nanda-Hamner and Bünsow experiments (Nanda & Hammer, 1958; Bünsow, 1960)...
December 2016: Physiological Entomology
https://www.readbyqxmd.com/read/27617484/periphyton-biofilms-influence-net-methylmercury-production-in-an-industrially-contaminated-system
#19
Todd A Olsen, Craig C Brandt, Scott C Brooks
Mercury (Hg) methylation and methylmercury (MMHg) demethylation activity of periphyton biofilms from the industrially contaminated East Fork Poplar Creek, Tennessee (EFPC) were measured during 2014-2016 using stable Hg isotopic rate assays. (201)Hg(II) and MM(202)Hg were added to intact periphyton samples in ambient streamwater and the formation of MM(201)Hg and loss of MM(202)Hg were monitored over time and used to calculate first-order rate potentials for methylation and demethylation. The influences of location, temperature/season, light exposure and biofilm structure on methylation and demethylation potentials were examined...
October 18, 2016: Environmental Science & Technology
https://www.readbyqxmd.com/read/27591521/decrease-in-light-dark-cycle-of-microalgal-cells-with-computational-fluid-dynamics-simulation-to-improve-microalgal-growth-in-a-raceway-pond
#20
Zongbo Yang, Jun Cheng, Qing Ye, Jianzhong Liu, Junhu Zhou, Kefa Cen
In this study, computational fluid dynamics (CFD) was used to systemically analyze the movement of algae in a vortex flow field produced by up-down chute baffles. The average cell light/dark (L/D) cycle period, vertical fluid velocity, fraction of time the algae was resides in light zone and the L/D cycle period were investigated under different paddlewheel speeds and microalgal concentrations. Results showed that the L/D cycle period decreased but the vertical fluid velocity increased when the up-down chute baffles were used...
November 2016: Bioresource Technology
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