Pair Comparison and Ascending Series NaCl Thresholds: Criterion and Residual Effects

Perception ◽  
1974 ◽  
Vol 3 (2) ◽  
pp. 185-192 ◽  
Author(s):  
M O'Mahony ◽  
H Ivory ◽  
E King
Keyword(s):  
Presentation Order ◽  
Residual Effects ◽  
Taste Receptors ◽  
Pair Comparison ◽  
Nacl Concentration ◽  
Concentration Changes ◽  
Order Of Presentation ◽  
Detection And Recognition

Ascending series detection and recognition thresholds, both with and without interstimulus water rinses, and pair comparison thresholds, with varied presentation order, were measured for NaCl. Thresholds were measured in situ against a normal salivary background and also after rinses with 60 mM and 1 M NaCl. Predicted changes in the level of adaptation of the taste receptors, due to NaCl concentration changes in the mouth, were seen to vary the measured thresholds. Ascending series thresholds without interstimulus rinses were highest of all, although they were reduced by rinsing. The order of presentation in pair comparison tests was seen to vary thresholds in a manner predicted by proposed adaptation levels. Effects were also noted which were due to criterion definition and language. The trends found in the present experiments were also found in the literature.

Soil seed bank and vegetation dynamics in Sahelian fallows; the impact of past cropping and current grazing treatments

2004 ◽  
Vol 20 (6) ◽  
pp. 683-691 ◽  
Author(s):  
Bruno Hérault ◽  
Pierre Hiernaux
Keyword(s):  
Seed Bank ◽  
Management Practices ◽  
Soil Seed Bank ◽  
Residual Effects ◽  
Ex Situ ◽  
Phosphorus Fertilizer ◽  
Wet Season ◽  
Seed Extraction ◽  
The Impact

The soil seed bank in a 5-y-old Sahelian fallow was studied through seed extraction and compared with germinations recorded either in controlled conditions, ex situ in a glasshouse, or in the field. The influence of phosphorus fertilizer and mulch application during the preceding crop period, and that of seasonal grazing regimes applied the last 2 y of fallowing, were assessed on the composition of the seed stock. Ctenium elegans, Fimbristylis hispidula, Merremia pinnata and Phyllanthus pentandrus accounted together for 75% of extracted seeds, 72% of ex situ, and 62% of in situ seedlings. Mulch treatment was correlated with the first axis of the canonical correspondence analyses performed on the seedling datasets. Mulch and phosphorus fertilizer treatments held similar responses, as they both favoured the seed bank of erect dicotyledons such as P. pentandrus and Cassia mimosoides. On the whole, the effects of grazing remained modest compared with the residual effects of past crop management practices. However, seedling densities increased as a result of dry-season grazing, while the soil seed bank decreased with wet-season grazing. Grazing also reduced the spatial heterogeneity of the seed bank rather than the overall number of species.

scholarly journals The effects of the order of picture presentation on the subjective emotional evaluation of pictures

Psicologia ◽  
2020 ◽  
Vol 34 (2) ◽  
pp. 171-178
Author(s):  
Vladimir Kosonogov
Keyword(s):  
Subjective Evaluation ◽  
Presentation Order ◽  
Neutral Picture ◽  
Affective Valence ◽  
Sequential Effects ◽  
Emotional Evaluation ◽  
Picture Presentation ◽  
Valence And Arousal ◽  
Order Of Presentation

In the last twenty years, a great number of studies on subjective emotional evaluation of affective pictures have been published. However, it is well-known that the order of presentation may entail sequential effects, which is the perception of a previous stimulus that may influence the next stimulus's perception. Our study examines whether the order of picture presentation influences the subjective evaluation of their affective valence and arousal. The results showed some influence of the order of presentation on affective valence: unpleasant pictures at the end were less unpleasant than unpleasant pictures at the beginning, and the neutral picture, when presented after unpleasant pictures, was more pleasant than when presented after pleasant pictures. No effect of presentation order on arousal was found. These findings suggest that several picture presentation orders should be used in future experiments on emotions to avoid possible effects of the order on affective valence.

scholarly journals Non-destructive mid-IR spectroscopy with quantum cascade laser can detect ethylene gas dynamics of apple cultivar ‘Fuji’ in real time

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Masaki Yumoto ◽  
Yasushi Kawata ◽  
Tetsuya Abe ◽  
Tomoki Matsuyama ◽  
Satoshi Wada
Keyword(s):  
Real Time ◽  
Quantum Cascade Laser ◽  
Detection System ◽  
Gas Cell ◽  
Sampling System ◽  
Gas Sampling ◽  
Quantum Cascade ◽  
Concentration Changes ◽  
Non Destructive

AbstractMany plants, including fruits and vegetables, release biogenic gases containing various volatile organic compounds such as ethylene (C2H4), which is a gaseous phytohormone. Non-destructive and in-situ gas sampling technology to detect trace C2H4 released from plants in real time would be attractive for visualising the ageing, ripening, and defence reactions of plants. In this study, we developed a C2H4 detection system with a detection limit of 0.8 ppb (3σ) using laser absorption spectroscopy. The C2H4 detection system consists of a mid-infrared quantum cascade laser oscillated at 10.5 µm, a multi-pass gas cell, a mid-IR photodetector, and a gas sampling system. Using non-destructive and in-situ gas sampling, while maintaining the internal pressure of the multi-pass gas cell at low pressure, the change in trace C2H4 concentration released from apples (Malus domestica Borkh.) can be observed in real time. We succeeded in observing C2H4 concentration changes with a time resolution of 1 s, while changing the atmospheric gas and surface temperature of apples from the ‘Fuji’ cultivar. This technique allows the visualisation of detailed C2H4 dynamics in plant environmental response, which may be promising for further progress in plant physiology, agriculture, and food science.

scholarly journals Исследование нейроваскулярных структур с помощью фазово-модуляционной спектрофотометрии-=SUP=-*-=/SUP=-

2019 ◽  
Vol 126 (6) ◽  
pp. 820
Author(s):  
Л.П. Сафонова ◽  
В.Г. Орлова ◽  
А.Н. Шкарубо
Keyword(s):  
Phase Modulation ◽  
Biological Tissues ◽  
Endoscopic Endonasal ◽  
Endoscopic Neurosurgery ◽  
The Difference ◽  
Neurovascular Structures ◽  
Independent Parameters ◽  
Detection And Recognition

The possibility of using phase modulation spectrophotometry for the detection and recognition of large blood vessels and nerves in the biological tissues volume in the tasks of neurosurgery with endoscopic endonasal access while removing the skull base tumors has been investigated. Optical and dynamic characteristics of various neurovascular structures types were studied. Informative independent parameters and their corresponding criteria for the detection and recognition of neurovascular structures in the tissue volume, based on the difference in the optical properties of the blood, nerves and their surrounding tissues, was proposed and experimentally investigated in vivo and in situ. The obtained preliminary results indicate the promise of applying the method of phase modulation spectrophotometry in endoscopic neurosurgery and can be used in spectrophotometry with the impulse time-domain approach.

scholarly journals Arsenazo III and antipyrylazo III calcium transients in single skeletal muscle fibers.

1982 ◽  
Vol 79 (4) ◽  
pp. 679-707 ◽  
Author(s):  
P Palade ◽  
J Vergara
Keyword(s):  
Skeletal Muscle ◽  
Voltage Clamp ◽  
Spectral Characteristics ◽  
Muscle Fibers ◽  
Calcium Transients ◽  
Arsenazo Iii ◽  
Tension Development ◽  
Skeletal Muscle Fibers ◽  
Concentration Changes

The metallochrome calcium indicators arsenazo III and antipyrylazo III have been introduced individually into cut single frog skeletal muscle fibers from which calcium transients have been elicited either by action potential stimulation or by voltage-clamp pulses of up to 50 ms in duration. Calcium transients recorded with both dyes at selected wavelengths have similar characteristics when elicited by action potentials. Longer voltage-clamp pulse stimulation reveals differences in the late phases of the optical signals obtained with the two dyes. The effects of different tension blocking methods on Ca transients were compared experimentally. Internal application of EGTA at concentrations up to 3 mM was demonstrated to be efficient in blocking movement artifacts without affecting Ca transients. Higher EGTA concentrations affect the Ca signals' characteristics. Differential effects of internally applied EGTA on tension development as opposed to calcium transients suggest that diffusion with binding from Ca++ release sites to filament overlap sites may be significant. The spectral characteristics of the absorbance transients recorded with arsenazo III suggest that in situ recorded signals cannot be easily interpreted in terms of Ca concentration changes. A more exhaustic knowledge of the dye chemistry and/or in situ complications in the use of the dye will be necessary.

Electron and X-Ray Photon Radiation Effects on Surfaces of Lead Silicate Glasses

1996 ◽  
Vol 439 ◽  
Author(s):  
Paul W. Wang
Keyword(s):  
Radiation Effects ◽  
High Vacuum ◽  
Surface Radiation ◽  
Photon Radiation ◽  
Surface Relaxation ◽  
Lead Silicate ◽  
Metallic Lead ◽  
X Ray ◽  
Concentration Changes

AbstractRadiation effects on insulators have been extensively studied in terms of radiation induced damage. However, little work has concentrated on in situ surface modification during irradiation and the evolution of surface relaxation after the termination of irradiation. In this work, 1.3 keV electrons and 1.2536 keV Mg Kα X-ray photons were applied to investigate radiation effects on surface structural changes during irradiation and relaxation. The microstructure and composition of lead silicate glass were investigated in situ in an ultra-high-vacuum (UHV) environment by X-ray Photoelectron Spectroscopy (XPS). Similar surface radiation effects were observed using both types of radiation which included permanent metallic lead separation from the glass network resulting from Pb-O bond breaking, bimodal distribution of the 0 is XPS signal due to bridging and non-bridging oxygens, gradual increase of total lead and silicon concentrations and gradual decrease of oxygen concentration during relaxation. Different radiation effects for electron beam and X-ray photons were also observed. For photon irradiation, silicon and lead continuously accumulated while the oxygen on the surface continuously decreased during irradiation and relaxation. In the case of electron irradiation, both silicon and lead were depleted from the surface during irradiation and accumulated during relaxation. Opposite concentration changes were observed for oxygen; it increased during irradiation and decreased during relaxation. The experimental results are discussed in terms of charge effects, secondary electron yield, field-enhanced diffusion, non-bridging oxygens and nucleation of metallic lead.

scholarly journals T1R2 and T1R3 subunits are individually unnecessary for normal affective licking responses to polycose: implications for saccharide taste receptors in mice

2009 ◽  
Vol 296 (4) ◽  
pp. R855-R865 ◽  
Author(s):  
Yada Treesukosol ◽  
Ginger D. Blonde ◽  
Alan C. Spector
Keyword(s):  
Taste Receptor ◽  
Latin Square ◽  
Taste Receptors ◽  
Wild Type ◽  
Protein Subunits ◽  
Normal Concentration ◽  
Receptor Cells ◽  
Taste Receptor Cells ◽  
Access Test ◽  
Order Of Presentation

The T1R2 and T1R3 proteins are expressed in taste receptor cells and form a heterodimer binding with compounds described as sweet by humans. We examined whether Polycose taste might be mediated through this heterodimer by testing T1R2 knockout (KO) and T1R3 KO mice and their wild-type (WT) littermate controls in a series of brief-access taste tests (25-min sessions with 5-s trials). Sucrose, Na-saccharin, and Polycose were each tested for three consecutive sessions with order of presentation varied among subgroups in a Latin-Square manner. Both KO groups displayed blunted licking responses and initiated significantly fewer trials of sucrose and Na-saccharin across a range of concentrations. KO mice tested after Polycose exposure demonstrated some degree of concentration-dependent licking of sucrose, likely attributable to learning related to prior postingestive experience. These results are consistent with prior findings in the literature, implicating the T1R2+3 heterodimer as the principal taste receptor for sweet-tasting ligands, and also provide support for the potential of postingestive experience to influence responding in the KO mice. In contrast, T1R2 KO and T1R3 KO mice displayed concentration-dependent licking responses to Polycose that tracked those of their WT controls and in some cases licked midrange concentrations more; the number of Polycose trials initiated overall did not differ between KO and WT mice. Thus, the T1R2 and T1R3 proteins are individually unnecessary for normal concentration-dependent licking of Polycose to be expressed in a brief-access test. Whether at least one of these T1R protein subunits is necessary for normal Polycose responsiveness remains untested. Alternatively, there may be a novel taste receptor(s) that mediates polysaccharide taste.

scholarly journals Sweet-taste receptors, low-energy sweeteners, glucose absorption and insulin release

2010 ◽  
Vol 104 (10) ◽  
pp. 1415-1420 ◽  
Author(s):  
Andrew G. Renwick ◽  
Samuel V. Molinary
Keyword(s):  
Insulin Release ◽  
Taste Receptor ◽  
Sweet Taste ◽  
Glucose Absorption ◽  
Enteroendocrine Cells ◽  
Low Energy ◽  
Taste Receptors ◽  
Sweet Taste Receptors

The present review explores the interactions between sweeteners and enteroendocrine cells, and consequences for glucose absorption and insulin release. A combination of in vitro,in situ, molecular biology and clinical studies has formed the basis of our knowledge about the taste receptor proteins in the glucose-sensing enteroendocrine cells and the secretion of incretins by these cells. Low-energy (intense) sweeteners have been used as tools to define the role of intestinal sweet-taste receptors in glucose absorption. Recent studies using animal and human cell lines and knockout mice have shown that low-energy sweeteners can stimulate intestinal enteroendocrine cells to release glucagon-like peptide-1 and glucose-dependent insulinotropic peptide. These studies have given rise to major speculations that the ingestion of food and beverages containing low-energy sweeteners may act via these intestinal mechanisms to increase obesity and the metabolic syndrome due to a loss of equilibrium between taste receptor activation, nutrient assimilation and appetite. However, data from numerous publications on the effects of low-energy sweeteners on appetite, insulin and glucose levels, food intake and body weight have shown that there is no consistent evidence that low-energy sweeteners increase appetite or subsequent food intake, cause insulin release or affect blood pressure in normal subjects. Thus, the data from extensive in vivo studies in human subjects show that low-energy sweeteners do not have any of the adverse effects predicted by in vitro,in situ or knockout studies in animals.

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