A Phase Model of Temperature-Dependent Mammalian Cold Receptors

2000 ◽  
Vol 12 (5) ◽  
pp. 1067-1093 ◽  
Author(s):  
Peter Roper ◽  
Paul C. Bressloff ◽  
André Longtin
Keyword(s):  
Temperature Sensitivity ◽  
Dynamic Range ◽  
Variable Number ◽  
Phase Model ◽  
Temperature Dependent ◽  
Firing Patterns ◽  
Temperature Changes ◽  
Cold Receptor ◽  
Cold Receptors ◽  
Deterministic Limit

We present a tractable stochastic phase model of the temperature sensitivity of a mammalian cold receptor. Using simple linear dependencies of the amplitude, frequency, and bias on temperature, the model reproduces the experimentally observed transitions between bursting, beating, and stochastically phase-locked firing patterns. We analyze the model in the deterministic limit and predict, using a Strutt map, the number of spikes per burst for a given temperature. The inclusion of noise produces a variable number of spikes per burst and also extends the dynamic range of the neuron, both of which are analyzed in terms of the Strutt map. Our analysis can be readily applied to other receptors that display various bursting patterns following temperature changes.

Temperature-Dependent Photoluminescence Spectra of PbSe Quantum Dots for Temperature Markers

2012 ◽  
Vol 482-484 ◽  
pp. 2547-2550
Author(s):  
Peng Fei Gu ◽  
Ya Nan Wang ◽  
Jia Jia Cao ◽  
Yu Yan ◽  
Tie Qiang Zhang ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Temperature Sensitivity ◽  
Peak Position ◽  
Strong Temperature Dependence ◽  
Photoluminescence Spectra ◽  
Temperature Dependent ◽  
Temperature Variations ◽  
Temperature Changes ◽  
Optical Readout ◽  
Temperature Dependent Photoluminescence

We here report the temperature effect on photoluminescence(PL) spectra of PbSe quantum dots (QDs), which exhibit a strong temperature dependence on their spectra position and intensity. They potentially act as the temperature marker, sensing temperature variations and reporting temperature changes remotely through optical readout. In addition, the temperature sensitivity characterized by peak position of PbSe QDs was found to be 0.39nm/°C in a range of 10-100 °C.

scholarly journals Emission Characteristics of Fluorescent Labels with Respect to Temperature Changes and Subsequent Effects on DNA Microchip Studies

2005 ◽  
Vol 71 (10) ◽  
pp. 6453-6457 ◽  
Author(s):  
Wen-Tso Liu ◽  
Jer-Horng Wu ◽  
Emily Sze-Ying Li ◽  
Ezrein Shah Selamat
Keyword(s):  
Melting Curve ◽  
Melting Curve Analysis ◽  
Emission Characteristics ◽  
Fluorescent Labels ◽  
Temperature Dependent ◽  
Temperature Changes ◽  
Formamide Concentration ◽  
Effects Of Temperature ◽  
Microarray Studies ◽  
Texas Red

ABSTRACT The effects of temperature, salt concentration, and formamide concentration on the emission characteristics of commonly used fluorescent labels were evaluated on DNA microchips. The emission intensities of different fluorophores without hybridization were observed to vary, each to a different extent, to mainly temperature changes. Rhodamine red, TAMRA (tetramethylrhodamine), and dyes from the carbocyanide group exhibited the largest variations, and Texas Red and Oregon Green exhibited the smallest variations. This temperature dependency was shown to affect results obtained during melting curve analysis in DNA microarray studies. To minimize the bias associated with the temperature-dependent emission of different fluorescent labels, a normalization step was proposed.

The Temperature-Dependent Ideal Shear Strength of Solid Single Crystals

2018 ◽  
Vol 85 (3) ◽  
Author(s):  
Tianbao Cheng ◽  
Daining Fang ◽  
Yazheng Yang
Keyword(s):  
Shear Strength ◽  
Theoretical Model ◽  
Melting Point ◽  
Single Crystals ◽  
Elevated Temperatures ◽  
Absolute Zero ◽  
Temperature Dependent ◽  
Temperature Changes ◽  
First Time ◽  
The Ideal

Knowledge of the ideal shear strength of solid single crystals is of fundamental importance. However, it is very hard to determine this quantity at finite temperatures. In this work, a theoretical model for the temperature-dependent ideal shear strength of solid single crystals is established in the view of energy. To test the drawn model, the ideal shear properties of Al, Cu, and Ni single crystals are calculated and compared with that existing in the literature. The study shows that the ideal shear strength first remains approximately constant and then decreases almost linearly as temperature changes from absolute zero to melting point. As an example of application, the “brittleness parameter” of solids at elevated temperatures is quantitatively characterized for the first time.

Temperature Sensitivity of Intracellular and Extracellular Soil Enzyme Activities

2021 ◽  
Author(s):  
Adetunji Alex Adekanmbi ◽  
Laurence Dale ◽  
Liz Shaw ◽  
Tom Sizmur
Keyword(s):  
Enzyme Activity ◽  
Soil Temperature ◽  
Temperature Sensitivity ◽  
Extracellular Enzymes ◽  
Extracellular Enzyme ◽  
Daily Maximum ◽  
Temperature Sensitive ◽  
Intracellular Enzyme ◽  
Temperature Changes ◽  
Som Decomposition

<p>Predicting the pattern of soil organic matter (SOM) decomposition as a feedback to climate change, via release of CO<sub>2</sub>, is extremely complex and has received much attention. However, investigations often do not differentiate between the extracellular and intracellular processes involved and work is needed to identify their relative temperature sensitivities. Samples were collected from a grassland soil at Sonning, UK with average daily maximum and minimum soil temperature of 15 °C and 5 °C. We measured potential activities of β-glucosidase (BG) and chitinase (NAG) (extracellular enzymes) and glucose-induced CO<sub>2 </sub>respiration (intracellular enzymes) at a range of assay temperatures (5 °C, 15 °C, 26 °C, 37<sup>  </sup>°C, and 45 °C). The temperature coefficient Q<sub>10</sub> (the increase in enzyme activity that occurs after a 10 °C increase in soil temperature) was calculated to assess the temperature sensitivity of intracellular and extracellular enzymes activities. Between 5 °C and 15 °C intracellular and extracellular enzyme activities had equal temperature sensitivity, but between 15 °C and 26°C intracellular enzyme activity was more temperature sensitive than extracellular enzyme activity and between 26 °C and 37 °C extracellular enzyme activity was more temperature sensitive than intracellular enzyme activity. This result implies that extracellular depolymerisation of higher molecular weight organic compounds is more sensitive to temperature changes at higher temperatures (e.g. changes to daily maximum summer temperature) but the intracellular respiration of the generated monomers is more sensitive to temperature changes at moderate temperatures (e.g. changes to daily mean summer temperature). We therefore conclude that the extracellular and intracellular steps of SOM mineralisation are not equally sensitive to changes in soil temperature. The finding is important because we have observed greater increases in average daily minimum temperatures than average daily mean or maximum temperatures due to increased cloud cover and sulphate aerosol emission. Accounting for this asymmetrical global warming may reduce the importance of extracellular depolymerisation and increase the importance of intracellular catalytic activities as the rate limiting step of SOM decomposition.</p>

scholarly journals A Computational Model of the Temperature-dependent Changes in Firing Patterns inAplysiaNeurons

2011 ◽  
Vol 15 (6) ◽  
pp. 371 ◽  
Author(s):  
Nam Gyu Hyun ◽  
Kwang-Ho Hyun ◽  
Kwang-Beom Hyun ◽  
Jin-Hee Han ◽  
Kyungmin Lee ◽  
...  
Keyword(s):  
Computational Model ◽  
Temperature Dependent ◽  
Firing Patterns

Temperature Sensitivity of Nanohole Array Sensors

2012 ◽  
Author(s):  
Mehmet Sen ◽  
Gregory Kowalski ◽  
Jason Fiering ◽  
Dale Larson
Keyword(s):  
Temperature Sensitivity ◽  
Wavelength Region ◽  
Gold Surface ◽  
Temperature Sensors ◽  
Light Sources ◽  
Nanohole Array ◽  
Temperature Changes ◽  
Helium Neon Laser ◽  
Helium Neon ◽  
Higher Sensitivity

Small, sensitive temperature sensors are required to develop chip-scale calorimeters for pharmaceutical and related industries. Laser illuminated nanohole array apertures (NHA) that produce extraordinary optical transmission (EOT) perform as temperature sensors and may be suitable for micro-calorimetry. We investigated NHA sensors by an experimental parametric study to determine the most sensitive configuration. Temperature sensitivity of EOT is discussed, and the results suggest that nanohole arrays enable thermal measurements with microscale spatial resolution. The sensing chip is a glass substrate with 105nm thick gold surface, illuminated with a helium–neon laser. 15 different designs were milled in a formation of 3×5 matrix. Each row has a different array size (3×3, 5×5 and 10×10) and each column has a different pitch size varying from 250nm to 450nm in 50nm increments. The aperture size was fixed at 150 nm, thus the overall size of the array varies from 0.65μm×0.65μm to 4.20μm×4.20μm. The highest sensitivity was achieved with 350nm and 400nm pitch sensors and a 10×10 array (up to8% intensity gain per 0.10°C). These conditions correspond to a predicted peak wavelength region with high transmission gradients, due to the transmission maxima, causing higher sensitivity. This behavior was consistent in all array sizes. Results also showed that even the smallest sensors are sensitive to temperature changes, and they suggest a means for designing future NHA sensors to accommodate different light sources and fluids.

Temperature-dependent transitions of burst firing patterns in a model pyramidal neuron

2012 ◽  
Vol 44 (4) ◽  
pp. 265-273 ◽  
Author(s):  
L. Wang ◽  
S. Liu ◽  
J. Zhang ◽  
Y. Zeng
Keyword(s):  
Pyramidal Neuron ◽  
Burst Firing ◽  
Temperature Dependent ◽  
Firing Patterns

scholarly journals The Effects of Polarizing Current on Nerve Terminal Impulses Recorded from Polymodal and Cold Receptors in the Guinea-pig Cornea

2002 ◽  
Vol 120 (3) ◽  
pp. 395-405 ◽  
Author(s):  
Richard W. Carr ◽  
Svetlana Pianova ◽  
James A. Brock
Keyword(s):  
Guinea Pig ◽  
Nerve Terminal ◽  
Sensory Nerve ◽  
Outward Current ◽  
Nerve Terminals ◽  
Functional Difference ◽  
Inward Current ◽  
Cold Receptor ◽  
Cold Receptors

It was reported recently that action potentials actively invade the sensory nerve terminals of corneal polymodal receptors, whereas corneal cold receptor nerve terminals are passively invaded (Brock, J.A., S. Pianova, and C. Belmonte. 2001. J. Physiol. 533:493–501). The present study investigated whether this functional difference between these two types of receptor was due to an absence of voltage-activated Na+ conductances in cold receptor nerve terminals. To address this question, the study examined the effects of polarizing current on the configuration of nerve terminal impulses recorded extracellularly from single polymodal and cold receptors in guinea-pig cornea isolated in vitro. Polarizing currents were applied through the recording electrode. In both receptor types, hyperpolarizing current (+ve) increased the negative amplitude of nerve terminal impulses. In contrast, depolarizing current (−ve) was without effect on polymodal receptor nerve terminal impulses but increased the positive amplitude of cold receptor nerve terminal impulses. The hyperpolarization-induced increase in the negative amplitude of nerve terminal impulses represents a net increase in inward current. In both types of receptor, this increase in inward current was reduced by local application of low Na+ solution and blocked by lidocaine (10 mM). In addition, tetrodotoxin (1 μM) slowed but did not reduce the hyperpolarization-induced increase in the negative amplitude of polymodal and cold nerve terminal impulses. The depolarization-induced increase in the positive amplitude of cold receptor nerve terminal impulses represents a net increase in outward current. This change was reduced both by lidocaine (10 mM) and the combined application of tetraethylammomium (20 mM) and 4-aminopyridine (1 mM). The interpretation is that both polymodal and cold receptor nerve terminals possess high densities of tetrodotoxin-resistant Na+ channels. This finding suggests that in cold receptors, under normal conditions, the Na+ conductances are rendered inactive because the nerve terminal region is relatively depolarized.

Cl- regulates cryoglobulin structure: a new hypothesis for the physiopathological mechanism of temperature non-dependent cryoprecipitation

2004 ◽  
Vol 42 (6) ◽  
Author(s):  
Enrico Di Stasio ◽  
Patrizia Bizzarri ◽  
Milvia Casato ◽  
Antonio Galtieri ◽  
Massimo Fiorilli ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Clinical Signs ◽  
Cold Temperature ◽  
Pathogenetic Mechanism ◽  
Temperature Dependent ◽  
Temperature Changes ◽  
Significant Temperature ◽  
Neoplastic Disorders ◽  
New Hypothesis

AbstractCryoglobulins are pathological cold-precipitable immunoglobulins associated with a number of infectious, autoimmune and neoplastic disorders. Patients, when exposed to low temperatures, show symptoms related to intravascular precipitation of such immunoglobulins. The formation of cryoaggregates induced by exposure to cold temperature is the key pathogenetic mechanism. The subsequent intravascular precipitation can account for some clinical signs of peripheral vasculitis, but fails to explain the precipitation of cryoglobulins in regions where no significant temperature changes take place. We studied, in vitro, the activity of different ions on temperature-dependent aggregation of cryoglobulins and found that the concentration of Cl

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