scholarly journals Directional sensitivity in the thermal response of the facial pit in western diamondback rattlesnakes (Crotalus atrox)

2012 ◽  
Vol 215 (15) ◽  
pp. 2630-2636 ◽  
Author(s):  
T. Kohl ◽  
S. E. Colayori ◽  
G. Westhoff ◽  
G. S. Bakken ◽  
B. A. Young
1988 ◽  
Vol 102 ◽  
pp. 41
Author(s):  
E. Silver ◽  
C. Hailey ◽  
S. Labov ◽  
N. Madden ◽  
D. Landis ◽  
...  

The merits of microcalorimetry below 1°K for high resolution spectroscopy has become widely recognized on theoretical grounds. By combining the high efficiency, broadband spectral sensitivity of traditional photoelectric detectors with the high resolution capabilities characteristic of dispersive spectrometers, the microcalorimeter could potentially revolutionize spectroscopic measurements of astrophysical and laboratory plasmas. In actuality, however, the performance of prototype instruments has fallen short of theoretical predictions and practical detectors are still unavailable for use as laboratory and space-based instruments. These issues are currently being addressed by the new collaborative initiative between LLNL, LBL, U.C.I., U.C.B., and U.C.D.. Microcalorimeters of various types are being developed and tested at temperatures of 1.4, 0.3, and 0.1°K. These include monolithic devices made from NTD Germanium and composite configurations using sapphire substrates with temperature sensors fabricated from NTD Germanium, evaporative films of Germanium-Gold alloy, or material with superconducting transition edges. A new approache to low noise pulse counting electronics has been developed that allows the ultimate speed of the device to be determined solely by the detector thermal response and geometry. Our laboratory studies of the thermal and resistive properties of these and other candidate materials should enable us to characterize the pulse shape and subsequently predict the ultimate performance. We are building a compact adiabatic demagnetization refrigerator for conveniently reaching 0.1°K in the laboratory and for use in future satellite-borne missions. A description of this instrument together with results from our most recent experiments will be presented.


Author(s):  
Peter D. Moisiuk ◽  
Daniel R. Beniac ◽  
Ross A. Ridsdale ◽  
Martin Young ◽  
Bhushan Nagar ◽  
...  

Venom from the rattlesnake Crotalus atrox contains a mixture of enzymes that induce a localized effect leading to hemorrhaging, necrosis and edema. As a member of the crotalid family of snake venoms, Crotalus atrox venom contains a C-type lectin that will agglutinate blood cells in a Ca2+-dependent fashion. The lectin is a hydrophilic protein, consisting of two covalently linked, 135 amino acid residues, identical subunits that are rich in aspartic acid, glutamic acid and lysine. Sequence homology with known carbohydrate recognition domains (CRDs) indicates that rattlesnake venom lectin (RSLV) contains a CRD motif that is not linked to accessory domains. Preliminary X-ray diffraction and sedimentation analysis has indicated that lectin from Crotalus atrox forms decamers composed of two five-fold symmetric pentamers. Single particles of RSVL imaged at – 171°C displayed two distinct orientations on the specimen support (Figure a) following incubation in a crystallization Teflon well, coated with a lipid monolayer consisting of phosphatidylcholine and monosialoganglioside. When lying in an end-on orientation, the lectin exhibited a “pentagonal ring” with an outer diameter of 6.7 nm and an inner hollow core of 1.7 nm. A side orientation was also seen, whereby a thickness of 5.8 nm was measured for the lectin. Image processing of 2280 single particles placed in 100 classes (Figure b) led to 3D reconstructions of RSVL (Figure c). Density limited 3D reconstructions showed the lectin to be made of two five-fold symmetrical rings covalently linked between the five subunits that constitute each ring of this homodimer. These results are consistent with sedimentation and preliminary X-ray diffraction analysis on the shape of RSVL and provide the framework for structural verification by 2D electron crystallography.


2020 ◽  
pp. 57-65
Author(s):  
Eusébio Conceiçã ◽  
João Gomes ◽  
Maria Manuela Lúcio ◽  
Jorge Raposo ◽  
Domingos Xavier Viegas ◽  
...  

This paper refers to a numerical study of the hypo-thermal behaviour of a pine tree in a forest fire environment. The pine tree thermal response numerical model is based on energy balance integral equations for the tree elements and mass balance integral equation for the water in the tree. The simulation performed considers the heat conduction through the tree elements, heat exchanges by convection between the external tree surfaces and the environment, heat exchanges by radiation between the flame and the external tree surfaces and water heat loss by evaporation from the tree to the environment. The virtual three-dimensional tree model has a height of 7.5 m and is constituted by 8863 cylindrical elements representative of its trunks, branches and leaves. The fire front has 10 m long and a 2 m high. The study was conducted taking into account that the pine tree is located 5, 10 or 15 m from the fire front. For these three analyzed distances, the numerical results obtained regarding to the distribution of the view factors, mean radiant temperature and surface temperatures of the pine tree are presented. As main conclusion, it can be stated that the values of the view factor, MRT and surface temperatures of the pine tree decrease with increasing distance from the pine tree in front of fire.


1997 ◽  
Vol 503 ◽  
Author(s):  
Yongxia Zhang ◽  
Yanwei Zhang ◽  
Juliana Blaser ◽  
T. S. Sriiram ◽  
R. B. Marcus

ABSTRACTA thermal microprobe has been designed and built for high resolution temperature sensing. The thermal sensor is a thin-film thermocouple junction at the tip of an Atomic Force Microprobe (AFM) silicon probe needle. Only wafer-stage processing steps are used for the fabrication. The thermal response over the range 25–s 4.5–rovolts per degree C and is linear.


Author(s):  
Nova T. Zamora ◽  
Kam Meng Chong ◽  
Ashish Gupta

Abstract This paper presented the recent application of die powerup in Thermal Imaging as applied to the detection of defects causing thermal failure on revenue products or units not being captured using other available techniques. Simulating the condition on an actual computer setup, the infrared (IR) camera should capture images simultaneously as the entire bootup process is being executed by the processor, thus revealing a series of images and thermal information on each and every step of the startup process. This metrology gives the failure analyst a better approach to acquire a set of information that substantiate in the conduct of rootcause analysis of thermal-related failure in revenue units, especially on customer returns. Defective units were intentionally engineered in order to collect the thermal response data and eventually come up with a plot of all known thermal-related defects.


Author(s):  
Yongmei Liu ◽  
Rajen Dias

Abstract Study presented here has shown that Infrared thermography has the potential to be a nondestructive analysis tool for evaluating package sublayer defects. Thermal imaging is achieved by applying pulsed external heating to the package surface and monitoring the surface thermal response as a function of time with a high-speed IR camera. Since the thermal response of the surface is affected by the defects such as voids and delamination below the package surface, the technique can be used to assist package defects detection and analysis.


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