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https://www.readbyqxmd.com/read/29215784/neither-dark-nor-light-but-shades-in-between-cocoa-merits-a-finer-sampling
#1
Lindsey Norgrove
Abdulai et al. (2017), working in Akumadan in the forest-savannah transition zone of Ghana, compared three cocoa (Theobroma cacao) systems in periods of wet, dry and extremely dry weather. These were cocoa grown: (a) in an agroforestry system under a leguminous tree (Albizia ferruginea); (b) in an agroforestry system under one of the most common shade trees (Antiaris toxicaria) in the region; and, (c) under "full sun conditions". During the extremely dry period, the cocoa in agroforestry systems had massive stress, reduced sap flux and high mortality...
December 7, 2017: Global Change Biology
https://www.readbyqxmd.com/read/29210963/central-ellipsoid-loss-associated-with-cone-dystrophy-and-kcnv2-mutation
#2
David Xu, Daniel Su, Steven Nusinowitz, David Sarraf
PURPOSE: To report a case of central ellipsoid loss with supernormal rod electroretinogram and KCNV2 gene mutation. METHODS: Retrospective case report. PATIENT: Thirty-eight-year-old man. RESULTS: We report a patient with longstanding vision loss and photophobia who illustrated central atrophy of the inner segment ellipsoid zone band on spectral domain optical coherence tomography. Fundus autofluorescence displayed mild perifoveal mottled autofluorescence...
November 23, 2017: Retinal Cases & Brief Reports
https://www.readbyqxmd.com/read/29203177/characterisation-analysis-of-expression-and-localisation-of-the-opsin-gene-repertoire-from-the-perspective-of-photoperiodism-in-the-aphid-acyrthosiphon-pisum
#3
Jorge Mariano Collantes-Alegre, Florian Mattenberger, Miquel Barberà, David Martínez-Torres
Organisms exhibit a wide range of seasonal responses as adaptions to predictable annual changes in their environment. These changes are originally caused by the effect of the Earth's cycles around the sun and its axial tilt. Examples of seasonal responses include floration, migration, reproduction and diapause. In temperate climate zones, the most robust variable to predict seasons is the length of the day (i.e. the photoperiod). The first step to trigger photoperiodic driven responses involves measuring the duration of the light-dark phases, but the molecular clockwork performing this task is poorly characterized...
December 1, 2017: Journal of Insect Physiology
https://www.readbyqxmd.com/read/29114241/a-nanoscale-study-of-carbon-and-nitrogen-fluxes-in-mats-of-purple-sulfur-bacteria-implications-for-carbon-cycling-at-the-surface-of-coastal-sediments
#4
Cédric Hubas, Dominique Boeuf, Bruno Jesus, Najet Thiney, Yann Bozec, Christian Jeanthon
Mass blooms of purple sulfur bacteria growing seasonally on green stranded macroalgae have a major impact on the microbial composition and functionality of intertidal mats. To explore the active anoxygenic phototrophic community in purple bacterial mats from the Roscoff Aber Bay (Brittany, France), we conducted a combined approach including molecular and high-resolution secondary ion mass spectrometry (NanoSIMS) analyses. To investigate the dynamics of carbon and nitrogen assimilation activities, NanoSIMS was coupled with a stable isotope probing (SIP) experiment and a compound specific isotope analysis (CSIA) of fatty acid methyl ester (FAME)...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/29080930/dysfunction-of-gabaergic-neurons-in-the-parafacial-zone-mediates-sleep-disturbances-in-a-streptozotocin-induced-rat-model-of-sporadic-alzheimer-s-disease
#5
Jin-Zhi Song, Su-Ying Cui, Xiang-Yu Cui, Xiao Hu, Yu-Nu Ma, Hui Ding, Hui Ye, Yong-He Zhang
Sleep disturbances are prevalent among patients with Alzheimer's disease (AD) and often precede the onset and progression of dementia. However, there are no reliable animal models for investigating sleep disturbances in patients with sporadic AD (sAD), which accounts for more than 90% of all AD cases. In the present study, we characterize the sleep/wake cycles and explore a potential mechanism underlying sleep disturbance in a rat model of sAD induced via intracerebroventricular (icv) injection of streptozotocin (STZ)...
October 28, 2017: Metabolic Brain Disease
https://www.readbyqxmd.com/read/29017090/combinatory-effects-of-low-concentrations-of-17%C3%AE-etinylestradiol-and-citalopram-on-non-reproductive-behavior-in-adult-zebrafish-danio-rerio
#6
Tove Porseryd, Martin Kellner, Nasim Reyhanian Caspillo, Kristina Volkova, Lubna Elabbas, Shahid Ullah, Håkan Olsén, Patrik Dinnétz, Inger Porsch Hällström
Sewage effluents contain pharmaceuticals, personal care products and industrial chemicals, exposing aquatic organisms to complex mixtures. The consequences of exposure to combinations of different classes of drugs in fish are largely unknown. In this study, we exposed adult zebrafish (Danio rerio) males and females for two weeks to low, environmentally relevant concentrations of the endocrine disrupting chemical 17α-etinylestradiol (EE2) and the selective serotonin re-uptake inhibitor (SSRI) citalopram, alone and in combination, and analyzed behaviors of importance for population fitness, scototaxis (light/dark preference), the novel tank test and shoal cohesion...
October 4, 2017: Aquatic Toxicology
https://www.readbyqxmd.com/read/28987464/reentrainment-of-the-circadian-pacemaker-during-jet-lag-east-west-asymmetry-and-the-effects-of-north-south-travel
#7
Casey O Diekman, Amitabha Bose
The normal alignment of circadian rhythms with the 24-h light-dark cycle is disrupted after rapid travel between home and destination time zones, leading to sleep problems, indigestion, and other symptoms collectively known as jet lag. Using mathematical and computational analysis, we study the process of reentrainment to the light-dark cycle of the destination time zone in a model of the human circadian pacemaker. We calculate the reentrainment time for travel between any two points on the globe at any time of the day and year...
October 4, 2017: Journal of Theoretical Biology
https://www.readbyqxmd.com/read/28978732/diatoms-dominate-the-eukaryotic-metatranscriptome-during-spring-in-coastal-dead-zone-sediments
#8
Elias Broman, Varvara Sachpazidou, Mark Dopson, Samuel Hylander
An important characteristic of marine sediments is the oxygen concentration that affects many central metabolic processes. There has been a widespread increase in hypoxia in coastal systems (referred to as 'dead zones') mainly caused by eutrophication. Hence, it is central to understand the metabolism and ecology of eukaryotic life in sediments during changing oxygen conditions. Therefore, we sampled coastal 'dead zone' Baltic Sea sediment during autumn and spring, and analysed the eukaryotic metatranscriptome from field samples and after incubation in the dark under oxic or anoxic conditions...
October 11, 2017: Proceedings. Biological Sciences
https://www.readbyqxmd.com/read/28946369/the-effects-of-different-dry-roast-parameters-on-peanut-quality-using-an-industrial-belt-type-roaster-simulator
#9
Xiaolei Shi, Lisa O Dean, Jack P Davis, K P Sandeep, Timothy H Sanders
Peanuts roasted to equivalent surface colors at different temperature/time combinations can vary substantially in chemical and physical properties related to product quality. This study used a pilot plant scale roaster that simulates the configurations of one of the most common industrial roaster, a multi-zone belt roaster. Jumbo-size runner-type peanuts were systematically roasted at 5 temperatures (149-204°C) to three Hunter l-values of 53, 48.5, and 43, corresponding to light, medium, and dark roasts. Moisture and tocopherol contents were more closely correlated with roast color rather than temperature, with exceptions at 149°C...
February 1, 2018: Food Chemistry
https://www.readbyqxmd.com/read/28935768/the-microanatomic-segregation-of-selection-by-apoptosis-in-the-germinal-center
#10
Christian T Mayer, Anna Gazumyan, Ervin E Kara, Alexander D Gitlin, Jovana Golijanin, Charlotte Viant, Joy Pai, Thiago Y Oliveira, Qiao Wang, Amelia Escolano, Max Medina-Ramirez, Rogier W Sanders, Michel C Nussenzweig
B cells undergo rapid cell division and affinity maturation in anatomically distinct sites in lymphoid organs called germinal centers (GCs). Homeostasis is maintained in part by B cell apoptosis. However, the precise contribution of apoptosis to GC biology and selection is not well defined. We developed apoptosis-indicator mice and used them to visualize, purify, and characterize dying GC B cells. Apoptosis is prevalent in the GC, with up to half of all GC B cells dying every 6 hours. Moreover, programmed cell death is differentially regulated in the light zone and the dark zone: Light-zone B cells die by default if they are not positively selected, whereas dark-zone cells die when their antigen receptors are damaged by activation-induced cytidine deaminase...
October 13, 2017: Science
https://www.readbyqxmd.com/read/28934124/n-halamine-biocidal-materials-with-superior-antimicrobial-efficacies-for-wound-dressings
#11
Buket Demir, Roy M Broughton, Mingyu Qiao, Tung-Shi Huang, S D Worley
This work demonstrated the successful application of N-halamine technology for wound dressings rendered antimicrobial by facile and inexpensive processes. Four N-halamine compounds, which possess different functional groups and chemistry, were synthesized. The N-halamine compounds, which contained oxidative chlorine, the source of antimicrobial activity, were impregnated into or coated onto standard non-antimicrobial wound dressings. N-halamine-employed wound dressings inactivated about 6 to 7 logs of Staphylococcus aureus and Pseudomonas aeruginosa bacteria in brief periods of contact time...
September 21, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28899751/homeostatic-and-circadian-mechanisms-of-bioluminescence-regulation-differ-between-a-forest-and-a-facultative-cave-species-of-glowworm-arachnocampa
#12
Sarah E Berry, Joshua Gilchrist, David J Merritt
Glowworms, members of the keroplatid fly genus, Arachnocampa, glow to attract prey. Here we describe substantial differences in the bioluminescence regulatory systems of two species; one is a troglophile with populations both in caves and outside of caves in wet forest (Arachnocampa tasmaniensis) and the other has no known cave populations (Arachnocampa flava). We find that A. tasmaniensis is ready to initiate bioluminescence at any time darkness is encountered. In contrast, A. flava shows a homeostatic control of bioluminescence; it is unlikely to initiate bioluminescence when exposed to dark pulses during the photophase and it does so with a long latency...
September 9, 2017: Journal of Insect Physiology
https://www.readbyqxmd.com/read/28888038/influence-of-littoral-periphyton-on-whole-lake-metabolism-relates-to-littoral-vegetation-in-humic-lakes
#13
Jussi Vesterinen, Shawn P Devlin, Jari Syväranta, Roger I Jones
The role of littoral habitats in lake metabolism has been underrated, especially in humic lakes, based on an assumption of low benthic primary production (PP) due to low light penetration into water. This assumption has been challenged by recent recognition of littoral epiphyton dominance of whole-lake PP in a small highly humic lake and of epiphyton as an important basal food source for humic lake biota. However, as these studies have mostly concerned single lakes, there is a need to test their wider generality...
September 9, 2017: Ecology
https://www.readbyqxmd.com/read/28852865/microalgal-cultivation-and-hydrodynamic-characterization-using-a-novel-tubular-photobioreactor-with-helical-blade-rotors
#14
Lichen He, Weimin Yang, Changfeng Guan, Hua Yan, Pengcheng Fu
Industrial-scale microalgal cultivation for food, feedstocks and biofuel production is limited by several engineering factors, such as cultivation systems. As a closed microalgal growth system, tubular photobioreactors are the most preferred ones in the mass algae production. In this work, microalgal cultivation and hydrodynamic characterization using a novel tubular photobioreactor equipped with helical blade rotors (HBRs) were investigated, with the aid of computational fluid dynamics and cultivation experiments to evaluate the effect of HBRs on the performance of tubular photobioreactor and growth of the Chlorella sp...
December 2017: Bioprocess and Biosystems Engineering
https://www.readbyqxmd.com/read/28790889/the-calcineurin-binding-activity-dependent-splice-variant-dynamin1xb-is-highly-enriched-in-synapses-in-various-regions-of-the-central-nervous-system
#15
Marie-Lisa Eich, Ekta Dembla, Silke Wahl, Mayur Dembla, Karin Schwarz, Frank Schmitz
In the present study, we generated and characterized a splice site-specific monoclonal antibody that selectively detects the calcineurin-binding dynamin1 splice variant dynamin1xb. Calcineurin is a Ca(2+)-regulated phosphatase that enhances dynamin1 activity and is an important Ca(2+)-sensing mediator of homeostatic synaptic plasticity in neurons. Using this dynamin1xb-specific antibody, we found dynamin1xb highly enriched in synapses of all analyzed brain regions. In photoreceptor ribbon synapses, dynamin1xb was enriched in close vicinity to the synaptic ribbon in a manner indicative of a peri-active zone immunolabeling...
2017: Frontiers in Molecular Neuroscience
https://www.readbyqxmd.com/read/28770653/simple-lighting-manipulations-facilitate-behavioral-entrainment-of-mice-to-18-h-days
#16
Thijs J Walbeek, Michael R Gorman
In an invariantly rhythmic world, a robust and stable mammalian circadian clock is presumed to confer fitness advantages. In shift-work or after rapid transmeridian travel, however, a stable clock might be maladaptive and a more flexibly resettable clock may have advantages. The rate at which rodents can adjust to simulated time zone travel and the range of entrainment can be markedly increased through simple light manipulations, namely, by exposing animals to extremely dim light (<0.01 lux) at night or by bifurcating rhythms under 24-h light-dark-light-dark (LDLD) cycles...
July 1, 2017: Journal of Biological Rhythms
https://www.readbyqxmd.com/read/28748375/attenuation-of-ethanol-abstinence-induced-anxiety-and-depressive-like-behavior-by-the-phosphodiesterase-4-inhibitor-rolipram-in-rodents
#17
Mei-Fang Gong, Rui-Ting Wen, Ying Xu, Jian-Chun Pan, Ning Fei, Yan-Meng Zhou, Jiang-Ping Xu, Jian-Hui Liang, Han-Ting Zhang
RATIONALE: Withdrawal symptoms stand as a core feature of alcohol dependence. Our previous results have shown that inhibition of phosphodiesterase-4 (PDE4) decreased ethanol seeking and drinking in alcohol-preferring rodents. However, little is known about whether PDE4 is involved in ethanol abstinence-related behavior. OBJECTIVE: The objective of this study was to characterize the role of PDE4 in the development of anxiety- and depressive-like behavior induced by abstinence from ethanol exposure in different animal models...
October 2017: Psychopharmacology
https://www.readbyqxmd.com/read/28710358/latitudinal-cline-of-chronotype
#18
Mario André Leocadio-Miguel, Fernando Mazzili Louzada, Leandro Lourenção Duarte, Roberta Peixoto Areas, Marilene Alam, Marcelo Ventura Freire, John Fontenele-Araujo, Luiz Menna-Barreto, Mario Pedrazzoli
The rotation of the Earth around its own axis and around the sun determines the characteristics of the light/dark cycle, the most stable and ancient 24 h temporal cue for all organisms. Due to the tilt in the earth's axis in relation to the plane of the earth's orbit around the sun, sunlight reaches the Earth differentially depending on the latitude. The timing of circadian rhythms varies among individuals of a given population and biological and environmental factors underlie this variability. In the present study, we tested the hypothesis that latitude is associated to the regulation of circadian rhythm in humans...
July 14, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28662189/affective-and-cognitive-behavior-in-the-alpha-galactosidase-a-deficient-mouse-model-of-fabry-disease
#19
Lukas Hofmann, Franziska Karl, Claudia Sommer, Nurcan Üçeyler
Fabry disease is an X-linked inherited lysosomal storage disorder with intracellular accumulation of globotriaosylceramide (Gb3) due to α-galactosidase A (α-Gal A) deficiency. Fabry patients frequently report of anxiety, depression, and impaired cognitive function. We characterized affective and cognitive phenotype of male mice with α-Gal A deficiency (Fabry KO) and compared results with those of age-matched male wildtype (WT) littermates. Young (3 months) and old (≥ 18 months) mice were tested in the naïve state and after i...
2017: PloS One
https://www.readbyqxmd.com/read/28661071/scheduled-meal-accelerates-entrainment-to-a-6-h-phase-advance-by-shifting-central-and-peripheral-oscillations-in-rats
#20
L M Ubaldo-Reyes, R M Buijs, C Escobar, M Ángeles-Castellanos
Travelling across several time zones requires a fast adjustment of the circadian system and the differential adjustment speeds of organs and systems results in what is commonly referred as jet lag. During this transitory state of circadian disruption, individuals feel discomfort, appetite loss, fatigue, disturbed sleep and deficient performance of multiple tasks. We have demonstrated that after a 6-h phase advance of the light-dark cycle (LD) scheduled food in phase with the new night onset can speed up re-entrainment...
August 2017: European Journal of Neuroscience
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