Freezing Point Determination in Immature Stages of Insects

1964 ◽  
Vol 96 (1-2) ◽  
pp. 158-158 ◽  
Author(s):  
C. R. Sullivan ◽  
G. W. Green
Keyword(s):  
Cold Hardiness ◽  
Freezing Point ◽  
Visual Observation ◽  
Freezing Process ◽  
Immature Stages ◽  
Filter Paper Disc ◽  
Recording Potentiometer ◽  
Binocular Microscope ◽  
The Moment ◽  
Freezing Chamber

Conventional and modified methods of obtaining supercooling points of immature stages of insects have been utilized in studies of the cold-hardiness of the European pine shoot moth and the European pinesawfly. A method has been developed to permit visual observation of the freezing process of more than one specimen at a time. A freezing chamber consisting of a hole one inch in depth and one-half inch in diameter is located in the upper end of an aluminum rod partially submerged in a dry ice-alcohol mixture. A small filter paper disc, used as the insect platform, rests upon a #40 copper-constantan thermocouple located near the base of the freezing chamber. The thermocouple enters the chamber through a hole in the wall after several circuits around the circumference of the rod to prevent temperature anomalies attributable to thermal conduction within the wire. The thermocouple is connected to a sensitive recording potentiometer. The wall of the freezing chamber is blackened to prevent reflection of light from obscuring the view of the freezing process, through a binocular microscope mounted above the freezing chamber. The moment of freezing is readily recorded on the temperature trace provided by the potentiometer. At a cooling rate of approximately 5°F. per minute, a correction factor of 2.5°F. must be added to the indicated freezing point to obtain the actual temperature at the surface of the platform. When this correction is applied, the results provide data applicable to statistical analysis of freezing point determinations.

Thermodynamic Theory and Experimental Validation of a Multiphase Isochoric Freezing Process

2019 ◽  
Vol 141 (8) ◽  
Author(s):  
Matthew J. Powell-Palm ◽  
Justin Aruda ◽  
Boris Rubinsky
Keyword(s):  
First Principles ◽  
Experimental Validation ◽  
Freezing Point ◽  
Physiological Saline ◽  
Physiological Solution ◽  
Freezing Process ◽  
Hypertonic Solution ◽  
Chemical Additives ◽  
Biological Matter ◽  
High Concentrations

Freezing of the aqueous solutions that comprise biological materials, such as isotonic physiological saline, results in the formation of ice crystals and the generation of a hypertonic solution, both of which prove deleterious to biological matter. The field of modern cryopreservation, or preservation of biological matter at subfreezing temperatures, emerged from the 1948 discovery that certain chemical additives such as glycerol, known as cryoprotectants, can protect cells from freeze-related damage by depressing the freezing point of water in solution. This gave rise to a slew of important medical applications, from the preservation of sperm and blood cells to the recent preservation of an entire liver, and current cryopreservation protocols thus rely heavily on the use of additive cryoprotectants. However, high concentrations of cryoprotectants themselves prove toxic to cells, and thus there is an ongoing effort to minimize cryoprotectant usage while maintaining protection from ice-related damage. Herein, we conceive from first principles a new, purely thermodynamic method to eliminate ice formation and hypertonicity during the freezing of a physiological solution: multiphase isochoric freezing. We develop a comprehensive thermodynamic model to predict the equilibrium behaviors of multiphase isochoric systems of arbitrary composition and validate these concepts experimentally in a simple device with no moving parts, providing a baseline from which to design tailored cryopreservation protocols using the multiphase isochoric technique.

The measurement of pF in soil by freezing-point

1938 ◽  
Vol 28 (4) ◽  
pp. 644-653 ◽  
Author(s):  
R. K. Schofield ◽  
J. V. Botelho da Costa
Keyword(s):  
Moisture Content ◽  
Soil Sample ◽  
Freezing Point ◽  
Freezing Temperature ◽  
The Moment ◽  
The Relationship

Two procedures are described for ascertaining the relationship between the freezing-point and moisture content of a soil. Since the soil sample is dried in the process of freezing, it is necessary to estimate how much water has been frozen out of the soil at the moment when the freezing temperature is recorded.Procedure A embodies all the precautions which appear desirable when the greatest accuracy is required. Procedure B is simple and rapid and yet accurate enough for routine estimations.

scholarly journals Generalized enthalpy model of a high-pressure shift freezing process

2012 ◽  
Vol 468 (2145) ◽  
pp. 2744-2766 ◽  
Author(s):  
Nadia A. S. Smith ◽  
Stephen S. L. Peppin ◽  
Ángel M. Ramos
Keyword(s):  
High Pressure ◽  
Stokes Equations ◽  
Freezing Point ◽  
Food Samples ◽  
Navier Stokes ◽  
Freezing Process ◽  
Frozen Foods ◽  
Navier Stokes Equations ◽  
Pressure Shift ◽  
Pressure Shift Freezing

High-pressure freezing processes are a novel emerging technology in food processing, offering significant improvements to the quality of frozen foods. To be able to simulate plateau times and thermal history under different conditions, in this work, we present a generalized enthalpy model of the high-pressure shift freezing process. The model includes the effects of pressure on conservation of enthalpy and incorporates the freezing point depression of non-dilute food samples. In addition, the significant heat-transfer effects of convection in the pressurizing medium are accounted for by solving the two-dimensional Navier–Stokes equations. We run the model for several numerical tests where the food sample is agar gel, and find good agreement with experimental data from the literature.

Freezing point and melting point of barnacle muscle fibers

1983 ◽  
Vol 61 (10) ◽  
pp. 1116-1121
Author(s):  
Jean-Pierre Caillé
Keyword(s):  
Phase Transition ◽  
Melting Point ◽  
Structural Component ◽  
Freezing Point ◽  
Muscle Fibers ◽  
Experimental Models ◽  
Freezing Process ◽  
Melting Points ◽  
Intact Muscle ◽  
Barnacle Muscle Fibers

The freezing point and the melting point of myoplasm were measured with two experimental models. In all samples, a supercooled stage was reached by lowering the temperature of the sample to approximately −7 °C, and the freezing of the sample was mechanically induced. The freezing process was associated with a phase transition in the interstices between the contractile filaments. In intact muscle fibers, the freezing point showed a structural component (0.43 °C), and the melting point indicated that the intracellular and the extracellular compartments are isotonic. When the sample of myoplasm, previously inserted in a cylindrical cavity was incubated in an electrolyte solution, the freezing point showed a structural component similar to that of the intact muscle fiber, but the melting point was lower than the freezing and the melting points of the embedding solution. This was interpreted as evidence that the counterions around the contractile filaments occupied a nonnegligible fraction of the intracellular compartment.

scholarly journals 280 Botryosphaeria dothidea Causes Premature Breaking of Endodormancy and Reduces Cold Hardiness in Cercis canadensis

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 490E-490
Author(s):  
A.M. Shirazi ◽  
K.A. Jacobs
Keyword(s):  
Woody Plants ◽  
Cold Hardiness ◽  
Visual Observation ◽  
Spore Suspension ◽  
Limiting Factors ◽  
Ion Leakage ◽  
Botryosphaeria Dothidea ◽  
Biotic Stresses ◽  
Cercis Canadensis ◽  
Artificial Freezing

Near-lethal abiotic stresses, e.g., low or high temperatures, chemicals, etc., can break endodormancy prematurely and reduce cold hardiness in woody plants. It is not well-ducumented whether biotic stresses can cause the same effect. Botryosphaeria dothidea causes canker in redbud (Cercis canadensis) and many other woody plants and is one of the most limiting factors growing redbud in the landscape. Two-year-old seedlings were planted in a nursery in May 1998 at The Morton Arboretum. Trees were inoculated (n = 10/treatment) with the fungus in Sept. 1998 using the stem slit method (a slit was cut about 5 cm above the base of the trunk and the wound was covered with parafilm after treatment). The treatments were T1 = control (PDA, Potato Dextrose Agar),T2 = 1-mm mycelium plug, T3 = low spore suspension (25 μL), T4 = high spore suspension (25 μL). Stem cold hardiness was evaluated by artificial freezing tests in Nov. 1998. The mean LT50 (the temperature at which 50% of the tissues is killed) from ion leakage were T1 (Control) = -29.3 °C, T2 (mycelium): -24.05 °C, T3 (low spore) = -18.75 °C, and T4 (high) = -16.4 °C. T3 and T4, the low- and high-spore inoculation, significantly reduced cold hardiness in redbud stem tissues. The LST (lowest survival temperature) based on visual observation of the samples after 7 days indicated all Botryosphaeria dothidea-treated plants had lower cold hardiness compared to control. Endodormancy was broken in B. dothidea-treated plants after placing plants under 16 h of light and 23 /18 °C day/night temperature for 1 month after the treatment. The highest percent budbrealk was for T4 (high spore), followed by T3 (Low Spore) and T2 (Mycelium).

scholarly journals SUBSTANTIATION AND SELECTION OF AN INHIBITOR FOR PREVENTING THE FORMATION OF ASPHALT-RESIN-PARAFFIN DEPOSITS

2020 ◽  
Vol 17 (34) ◽  
pp. 541-551 ◽  
Author(s):  
Karina Shamilevna KHAIBULLINA ◽  
Lyaisan Rustamovna SAGIROVA ◽  
Mikhail Sergeevich SANDYGA
Keyword(s):  
Freezing Point ◽  
Visual Observation ◽  
Hole Formation ◽  
Slowing Down ◽  
Relevant Today ◽  
Stage Of Development ◽  
Bottom Hole ◽  
Formation Zone ◽  
Organic Deposits ◽  
The Impact

Currently, most oil fields are under the late stage of development, which is associated with some challenges during the production of reservoir products, including the formation of asphalt-resin-paraffin deposits (ARPD) in the “well – bottom-hole formation zone” system. Even though the problem of organic deposits creation has existed for more than 60 years, it is still relevant today. Currently, to prevent the formation of ARPD, inhibitors divided into methods based on the use of wetting agents, modifiers, depressors, and dispersants are widely used infield practice. The composition of inhibitors often includes surfactants, and according to field experience, nonionic surfactants, namely, polyesters, are widely used to prevent the formation of ARPD. However, little is known about inhibitors with a combined effect, for example, possessing depressor-dispersing properties concerning ARPD. Proceeding from the above, the work is aimed to develop a combined inhibitor with depressor-dispersing properties to prevent the formation of ARPD. The dispersing property of the prepared reagent for asphaltene particles was determined using capillary and photocolorimetric methods. The studies were conducted to assess the impact of the reagent on the freezing point. A quantitative assessment of the sedimentation process using the “Cold rod” installation was performed, and the results of studies of the developed ARPD reagent-inhibitor corrosion resistance were presented. Two methods determined the temperature of oil saturation with paraffin: the direct approach – visual observation (Axio Lab A1 microscope) and the indirect approach – rheogoniometry to determine the kinematic viscosity of oil (HVM-472 viscosity analyzer (Walter Herzog GmbH, Germany)). Thus, an ARPD inhibitor (IN-1), comprising a copolymer of ethylene with α-olefins or polymers of acrylic, methacrylic, or cyanoacrylic acid esters, an emulsifier of inverted oil-in-water emulsions and a solvent, was developed. The developed inhibitor, having depressor-dispersing properties, is capable of reducing oil-freezing point in winter and of slowing down the precipitation of paraffin crystals in well equipped and in the bottom-hole formation zone (BHFZ).

Factors Influencing Cold Hardiness during Overwintering of Streltzoviella insularis (Lepidoptera: Cossidae)

2020 ◽  
Vol 113 (3) ◽  
pp. 1254-1261
Author(s):  
Jiahe Pei ◽  
Chengcheng Li ◽  
Lili Ren ◽  
Shixiang Zong
Keyword(s):  
Body Size ◽  
Cold Tolerance ◽  
Total Lipid ◽  
Cold Hardiness ◽  
Glycogen Content ◽  
Freezing Point ◽  
Total Lipid Content ◽  
Daily Minimum Temperature ◽  
Supercooling Point ◽  
Biochemical Basis

Abstract Streltzoviella insularis (Staudinger) (Lepidoptera: Cossidae) is a woodboring pest that severely damages urban and plain afforestation trees in northern China. Cold hardiness is an important strategy for the insect to survived during low winter temperatures. Understanding the strategy of S. insularis might provide insights for pest management approaches. To assess the key factors affecting cold hardiness, we measured the supercooling point, freezing point, total water content, total fat content, glycogen content, and total protein content of overwintering larvae. The relationships between supercooling points, temperature, body size, and nutrients were analyzed. The results showed that the supercooling point and freezing point of the larvae decreased first, reached the lowest point in January, and then increased during the rest of the overwintering period. The supercooling point positively correlated with the daily average temperature and the daily minimum temperature. Total lipid content negatively correlated with the supercooling point, while glycogen content had a significant positive correlation with the supercooling point. The temperature may have a major impact on cold hardiness, whereas individual body size may have no significant influence over cold tolerance. During the overwintering process, glycogen and total lipid contents may directly affect cold hardiness. Therefore, the lipid and carbohydrate metabolism may play a role in the cold tolerance of S. insularis larvae. This study provides a physiological and biochemical basis for future metabolic studies on S. insularis larva and the research of overwintering strategies.

Molecular cloning of heat shock protein 10 (Hsp10) and 60 (Hsp60) cDNAs from Galeruca daurica (Coleoptera: Chrysomelidae) and their expression analysis

2017 ◽  
Vol 108 (4) ◽  
pp. 510-522 ◽  
Author(s):  
Y. Tan ◽  
Y. Zhang ◽  
Z.-J. Huo ◽  
X.-R. Zhou ◽  
B.-P. Pang
Keyword(s):  
Amino Acids ◽  
Heat Shock ◽  
Heat Shock Protein ◽  
Mrna Expression ◽  
Expression Analysis ◽  
Stress Responses ◽  
Cold Hardiness ◽  
Treatment Time ◽  
Freezing Point ◽  
Northern China

AbstractGaleruca daurica (Joannis) is a new outbreak pest in the Inner Mongolia grasslands in northern China. Heat shock protein 10 and 60 (Hsp10 and Hsp60) genes of G. daurica, designated as GdHsp10 and GdHsp60, were cloned by rapid amplification of cDNA ends techniques. Sequence analysis showed that GdHsp10 and GdHsp60 encoded polypeptides of 104 and 573 amino acids, respectively. Sequence alignment and phylogenetic analysis clearly revealed that the amino acids of GdHsp10 and GdHsp60 had high homology and were clustered with other Hsp10 and Hsp60 genes in insects which are highly relative with G. daurica based on morphologic taxonomy. The mRNA expression analysis by real-time PCR revealed that GdHsp10 and GdHsp60 were expressed at all development stages and in all tissues examined, but expressed highest in eggs and in adults’ abdomen; both heat and cold stresses could induce mRNA expression of GdHsp10 and GdHsp60 in the 2nd instar larvae; the two Hsp genes were expressed from high to low with the extension of treatment time in G. daurica eggs exposed to freezing point. Overall, our study provides useful information to understand temperature stress responses of Hsp60 and Hsp10 in G. daurica, and provides a basis to further study functions of Hsp60/Hsp10 relative to thermotolerance and cold hardiness mechanism.

The issue of switching between non-freezing and freezing in soils

2020 ◽  
Author(s):  
Johanna Blöcher ◽  
Michal Kuraz
Keyword(s):  
Freezing Point ◽  
Pressure Head ◽  
Important Variable ◽  
Freezing Process ◽  
Total Water ◽  
Temperature Dependent ◽  
Freezing Front ◽  
Soil System ◽  
Clapeyron Equation ◽  
Natural Systems

<p>The freezing process in soils is important in many natural systems and, consequently, it is of great interest to model it accurately. <br>The freezing of water in soil is coupled to the heat equation as freezing releases latent heat and temperature is an important variable that determines whether water is in solid or liquid state. In soils, water can remain liquid under sub-zero temperatures (freezing-point depression). This effect is often modeled with the Clapeyron equation. With the Clapeyron equation, a temperature dependent pressure head definition for the total water content (liquid + frozen water) and the liquid water can be derived. When the temperature of the soil system falls below the freezing point, the system switches between the pressure head definitions. However, this switch can cause a discontinuity at the freezing front leading to numerical issues and unrealistic results.</p><p>To compensate for the discontinuity, we discuss the use of regularisation of the switching term on, both, synthetic and experimental data of case studies of freezing column experiments. </p>

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