scholarly journals The ‘dark phase’ in Sr2Ir1−x Rh x O4 revealed by Seebeck and Hall measurements

2021 ◽  
Vol 33 (21) ◽  
pp. 215602
Author(s):  
L Fruchter ◽  
V Brouet
Keyword(s):  
Dark Phase ◽  
Hall Measurements

The Souls of Muslim Folk

2012 ◽  
Vol 29 (4) ◽  
pp. 63-86
Author(s):  
Abdelwahab El-Affendi
Keyword(s):  
African Americans ◽  
Race Relations ◽  
Cultural Difference ◽  
Traumatic Experience ◽  
Recent History ◽  
Current Debate ◽  
Dark Phase ◽  
The West ◽  
European Culture

The current debate on the vices of multiculturalism and the merits of integration, of problematizing cultural difference, appears to miss important lessons from recent history in the treatment of minorities. In this paper, I start by questioning the celebration of Barack Obama’s election as a “breakthrough” for multicultural inclusiveness. I argue that the “Obama phenomenon” highlights the limits of democratic inclusiveness and sheds light on the traumatic experience of African Americans, who have been victimized precisely for seeking to assimilate. European Jews, especially in Germany, could not be accused of any reluctance to integrate either, and their contributions to European culture are legendary. But they also suffered grievously for their pains. Thus when the same xenophobic political trends traditionally hostile to the integration of minorities begin to vociferously demand that Muslims should integrate, this must be seen as a warning that we may be heading toward a very dark phase of race relations in the West.

scholarly journals Melatonin MT1 and MT2 Receptors Exhibit Distinct Effects in the Modulation of Body Temperature across the Light/Dark Cycle

2019 ◽  
Vol 20 (10) ◽  
pp. 2452 ◽  
Author(s):  
Martha López-Canul ◽  
Seung Hyun Min ◽  
Luca Posa ◽  
Danilo De Gregorio ◽  
Annalida Bedini ◽  
...  
Keyword(s):  
Body Temperature ◽  
Receptor Antagonist ◽  
Partial Agonist ◽  
Receptor Subtypes ◽  
Dark Phase ◽  
Light Phase ◽  
Dark Cycle ◽  
Simultaneous Activation ◽  
Type 3 ◽  
G Protein Coupled

Melatonin (MLT) is a neurohormone that regulates many physiological functions including sleep, pain, thermoregulation, and circadian rhythms. MLT acts mainly through two G-protein-coupled receptors named MT1 and MT2, but also through an MLT type-3 receptor (MT3). However, the role of MLT receptor subtypes in thermoregulation is still unknown. We have thus investigated the effects of selective and non-selective MLT receptor agonists/antagonists on body temperature (Tb) in rats across the 12/12-h light–dark cycle. Rectal temperature was measured every 15 min from 4:00 a.m. to 9:30 a.m. and from 4:00 p.m. to 9:30 p.m., following subcutaneous injection of each compound at either 5:00 a.m. or 5:00 p.m. MLT (40 mg/kg) had no effect when injected at 5 a.m., whereas it decreased Tb during the light phase only when injected at 5:00 p.m. This effect was blocked by the selective MT2 receptor antagonist 4P-PDOT and the non-selective MT1/MT2 receptor antagonist, luzindole, but not by the α1/MT3 receptors antagonist prazosin. However, unlike MLT, neither the selective MT1 receptor partial agonist UCM871 (14 mg/kg) nor the selective MT2 partial agonist UCM924 (40 mg/kg) altered Tb during the light phase. In contrast, UCM871 injected at 5:00 p.m. increased Tb at the beginning of the dark phase, whereas UCM924 injected at 5:00 a.m. decreased Tb at the end of the dark phase. These effects were blocked by luzindole and 4P-PDOT, respectively. The MT3 receptor agonist GR135531 (10 mg/kg) did not affect Tb. These data suggest that the simultaneous activation of both MT1 and MT2 receptors is necessary to regulate Tb during the light phase, whereas in a complex but yet unknown manner, they regulate Tb differently during the dark phase. Overall, MT1 and MT2 receptors display complementary but also distinct roles in modulating circadian fluctuations of Tb.

Electrical Characterization of Low Temperature GaAs Layers, and Observation of the Extremely Large Carrier Concentrations in Undoped Material

1991 ◽  
Vol 241 ◽  
Author(s):  
Bijan Tadayon ◽  
Mohammad Fatemi ◽  
Saied Tadayon ◽  
F. Moore ◽  
Harry Dietrich
Keyword(s):  
Molecular Beam Epitaxy ◽  
Low Temperature ◽  
Substrate Temperature ◽  
Molecular Beam ◽  
Electrical Characterization ◽  
Physical Characteristics ◽  
Hall Measurements ◽  
Undoped Material ◽  
Low Temperature Gaas

ABSTRACTWe present here the results of a study on the effect of substrate temperature, Ts, on the electrical and physical characteristics of low temperature (LT) molecular beam epitaxy GaAs layers. Hall measurements have been performed on the asgrown samples and on samples annealed at 610 °C and 850 °C. Si implantation into these layers has also been investigated.

scholarly journals Crossover from Landau Fermi liquid to non-Fermi liquid behavior: Indications from Hall measurements on CeCoIn5

2007 ◽  
Vol 460-462 ◽  
pp. 678-679
Author(s):  
C. Capan ◽  
S. Singh ◽  
S. Nair ◽  
M. Nicklas ◽  
H. Lee ◽  
...  
Keyword(s):  
Fermi Liquid ◽  
Hall Measurements ◽  
Liquid Behavior ◽  
Fermi Liquid Behavior

scholarly journals Ambient Air Temperature Assisted Crystallization for Inorganic CsPbI2Br Perovskite Solar Cells

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3398
Author(s):  
Yi Long ◽  
Kun Liu ◽  
Yongli Zhang ◽  
Wenzhe Li
Keyword(s):  
Solar Cells ◽  
Air Temperature ◽  
High Performance ◽  
Defect Density ◽  
Perovskite Solar Cells ◽  
Ambient Air ◽  
Dark Phase ◽  
High Quality ◽  
Ambient Air Temperature ◽  
Air Atmosphere

Inorganic cesium lead halide perovskites, as alternative light absorbers for organic–inorganic hybrid perovskite solar cells, have attracted more and more attention due to their superb thermal stability for photovoltaic applications. However, the humid air instability of CsPbI2Br perovskite solar cells (PSCs) hinders their further development. The optoelectronic properties of CsPbI2Br films are closely related to the quality of films, so preparing high-quality perovskite films is crucial for fabricating high-performance PSCs. For the first time, we demonstrate that the regulation of ambient temperature of the dry air in the glovebox is able to control the growth of CsPbI2Br crystals and further optimize the morphology of CsPbI2Br film. Through controlling the ambient air temperature assisted crystallization, high-quality CsPbI2Br films are obtained, with advantages such as larger crystalline grains, negligible crystal boundaries, absence of pinholes, lower defect density, and faster carrier mobility. Accordingly, the PSCs based on as-prepared CsPbI2Br film achieve a power conversion efficiency of 15.5% (the maximum stabilized power output of 15.02%). Moreover, the optimized CsPbI2Br films show excellent robustness against moisture and oxygen and maintain the photovoltaic dark phase after 3 h aging in an air atmosphere at room temperature and 35% relative humidity (R.H.). In comparison, the pristine films are completely converted to the yellow phase in 1.5 h.

scholarly journals CCK-8 and CCK-58 differ in their effects on nocturnal solid meal pattern in undisturbed rats

2012 ◽  
Vol 303 (8) ◽  
pp. R850-R860 ◽  
Author(s):  
Miriam Goebel-Stengel ◽  
Andreas Stengel ◽  
Lixin Wang ◽  
Gordon Ohning ◽  
Yvette Taché ◽  
...  
Keyword(s):  
Locomotor Activity ◽  
Food Intake ◽  
Molecular Forms ◽  
Reduce Food Intake ◽  
Dark Phase ◽  
Sprague Dawley ◽  
Solid Meal ◽  
Sprague Dawley Rats ◽  
And Behavior

Various molecular forms of CCK reduce food intake in rats. Although CCK-8 is the most studied form, we reported that CCK-58 is the only detectable endocrine peptide form in rats. We investigated the dark-phase rat chow intake pattern following injection of CCK-8 and CCK-58. Ad libitum-fed male Sprague-Dawley rats were intraperitoneally injected with CCK-8, CCK-58 (0.6, 1.8, and 5.2 nmol/kg), or vehicle. Food intake pattern was assessed during the dark phase using an automated weighing system that allowed continuous undisturbed monitoring of physiological eating behavior. Both CCK-8 and CCK-58 dose dependently reduced 1-h, dark-phase food intake, with an equimolar dose of 1.8 nmol being similarly effective (−49% and −44%). CCK-58 increased the latency to the first meal, whereas CCK-8 did not. The intermeal interval was reduced after CCK-8 (1.8 nmol/kg, −41%) but not after CCK-58. At this dose, CCK-8 increased the satiety ratio by 80% and CCK-58 by 160%, respectively, compared with vehicle. When behavior was assessed manually, CCK-8 reduced locomotor activity (−31%), whereas grooming behavior was increased (+59%). CCK-58 affected neither grooming nor locomotor activity. In conclusion, reduction of food intake by CCK-8 and CCK-58 is achieved by differential modulation of food intake microstructure and behavior. These data highlight the importance of studying the molecular forms of peptides that exist in vivo in tissue and circulation of the animal being studied.

scholarly journals Circadian Rhythm and Stress Response in Droppings ofSerinus canaria

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Maura Turriani ◽  
Nicola Bernabò ◽  
Barbara Barboni ◽  
Gianluca Todisco ◽  
Luigi Montini ◽  
...  
Keyword(s):  
Circadian Rhythm ◽  
Stress Response ◽  
Enzyme Immunoassay ◽  
Light Period ◽  
Daily Rhythm ◽  
Fecal Excretion ◽  
Dark Phase ◽  
Light Cycle ◽  
Serinus Canaria ◽  
Commercial Enzyme Immunoassay

Serinus canariais a widespread domestic ornamental songbird, whose limited knowledge of biology make compelling studies aimed to monitor stress. Here, a commercial enzyme immunoassay was adopted to measure immunoreactive corticosterone (CORT) in singleSerinus canariadropping sample, to monitor the daily fecal excretion of CORT in birds bred singly or in-group and to detect the effect promoted by aviary or small transport cage restraint. A robust daily rhythm of CORT was recorded in animals held on short-day light cycle, independent of bred conditions (single or group), which persisted when space availability was modified in single bred animal (transfer in aviary and transport cages). By contrast, a significant change in CORT excretion was recorded when group bred animals are restrained in a smaller cage. The daily rhythm in CORT excretion in response to manipulation showed the greatest response at the beginning of the light period, followed by the absence of the peak usually recorded at the end of the dark phase. These data indicated that EIA could be used as a reliable noninvasive approach to monitor the stress induced by restraint conditions inSerinus canaria.

scholarly journals Reverse Feeding Suppresses the Activity of the GH Axis in Rats and Induces a Preobesogenic State

Endocrinology ◽  
2011 ◽  
Vol 152 (3) ◽  
pp. 869-882 ◽  
Author(s):  
Camilla A.-M. Glad ◽  
Edward E. J. Kitchen ◽  
Gemma C. Russ ◽  
Sophie M. Harris ◽  
Jeffrey S. Davies ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Phase Inversion ◽  
Fatty Acid Synthase ◽  
Uncoupling Protein ◽  
Expression Patterns ◽  
Pulse Height ◽  
Male Rats ◽  
Dark Phase ◽  
Peroxisome Proliferator ◽  
Gh Secretion

Reversed feeding (RF) is known to disrupt hormone rhythmicity and metabolism. Although these effects may be mediated in part by phase inversion of glucocorticoid secretion, the precise mechanism is incompletely characterized. In this study, we demonstrate that acute nocturnal food deprivation in male rats suppressed the amplitude of spontaneous GH secretion during the dark phase by 62% (P < 0.001), without affecting baseline secretion. Prolonged RF, which reduced pituitary weight (by 22%; P < 0.05), also suppressed GH pulse height sufficiently to reduce skeletal growth (by 4–5%; P < 0.01) and terminal liver weight (by 11%; P < 0.001). Despite this suppression of the GH axis, proportionate adiposity was not elevated, probably due to the accompanying 16% reduction in cumulative food intake (P < 0.01). We demonstrate that RF also resulted in phase inversion of core clock gene expression in liver, abdominal white adipose tissue (WAT) and skeletal muscle, without affecting their expression patterns in the suprachiasmatic nucleus. In addition, RF resulted in phase inversion of hepatic peroxisome proliferator-activated receptor γ2 mRNA expression, a 3- to 5-fold elevation in fatty acid synthase mRNA in WAT in both light- and dark-phase samples (P < 0.01) and an elevation in muscle uncoupling protein 3 mRNA expression at the beginning of the light phase (P < 0.01). Consumption of a high-fat diet increased inguinal (by 36%; P < 0.05) and retroperitoneal WAT weight (by 72%; P < 0.01) only in RF-maintained rats, doubling the efficiency of lipid accumulation (P < 0.05). Thus, RF not only desynchronizes central and peripheral circadian clocks, and suppresses nocturnal GH secretion, but induces a preobesogenic state.

A Simple Method for Phase-contrast Microscopy: Improvements in Technique

1949 ◽  
Vol s3-90 (11) ◽  
pp. 323-329
Author(s):  
JOHN R. BAKER ◽  
D. A. KEMPSON ◽  
P.C. J. BRUNET
Keyword(s):  
Phase Contrast ◽  
Magnesium Fluoride ◽  
Phase Plate ◽  
Dark Phase ◽  
Phase Contrast Microscopy ◽  
Simple Method ◽  
Contrast Microscopy ◽  
Bull's Eye ◽  
Made In

The following are the main improvements that we have made in the method of phase-contrast microscopy described by Kempson, Thomas, and Baker (1948): 1. No bull's-eye condenser is used. The illuminant is an electric bulb with a ‘porcelain-processed’, ‘flashed white’, or ‘opal’ surface. 2. No oiled paper is placed over the illuminating annulus. 3. The thickness of the deposit of magnesium fluoride on the phase-plate is controlled by observations on the interference colours given by surface reflections. 4. Positive (dark) phase-contrast is preferred for most purposes to negative (bright).

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