Oviposition Behaviour in the Two Strains of the Rice Weevil, Calandra Oryzae Linn. (Coleopt., Curculionidae)

1951 ◽  
Vol 28 (3) ◽  
pp. 281-297
Author(s):  
F. SEGROVE
Keyword(s):  
Egg Production ◽  
Initial Rate ◽  
Large Strain ◽  
Small Strain ◽  
Oviposition Behaviour ◽  
Rice Weevil ◽  
Rapid Decline ◽  
High Initial Rate ◽  
Moisture Conditions ◽  
Better Than

The oviposition behaviour of the large strain of Calandra oryzae has been investigated at 20 and 25°C. and under moisture conditions equivalent to 50 and 70% R.H. The small strain of the weevil has been investigated at 25°C. and 70% R.H. At either temperature the lower humidity shortens the life of the insect and depresses the rate of oviposition so that fecundity is of a low order. Changes of temperature with a fixed humidity alter the rate of oviposition but have little effect on the total egg production. Under all conditions the pattern of oviposition remains the same, the oviposition rate rising to a peak in the earlier weeks of maturity and subsequently declining. Increasing the amount of grain leads to increasing egg production. It is unlikely that conditions for maximum fecundity were realised in the experiments. Isolating females in the early weeks of maturity leads to a high initial rate of oviposition, followed by a more rapid decline and little overall increase in fecundity. At 25°C. and 70% R.H. the fecundity of the large strain is of the order of 50% higher than that of the small strain. The distribution of eggs between grains differs in the two strains, the small strain distributing its eggs better than random, the large strain tending to overcrowd its eggs. The evidence suggests that this is due to the larger weevils' greater preference for large grains. By correlating the results with those from other sources it is nevertheless concluded that both strains tend to avoid laying in grains already containing life. The importance of this factor in oviposition behaviour is discussed.

Sitophilus sasakii (Tak.) (Coleoptera: Curculionidae) in Canada: Anatomy and Mycetomal Symbiotes as Valid Taxonomic Characters

1962 ◽  
Vol 94 (11) ◽  
pp. 1196-1197 ◽  
Author(s):  
A. J. Musgrave ◽  
R. Homan
Keyword(s):  
Large Strain ◽  
Small Strain ◽  
Rice Weevil ◽  
Small Species ◽  
Separate Species ◽  
Male And Female ◽  
Small Strains ◽  
The U.S ◽  
Shape And Size ◽  
Ecological Differences

Large and small strains of the rice weevil Sitophilus oryza (L.) (Calandra oryzae (L.) of authors following European usage) have been reported from several localities (Birch, 1944 in Australia; Kiritani, 1956 in Japan; Kono, 1955 in Nepal; Richards 1944 in Britain; and Utida, 1958, in Canada, Japan and U.S.A.). Birch and Richards both seem to have considered it probable that the two strains were separate species: but they did not make the separation. Floyd and Newsom (1960), after careful work on both strains found in the U.S. and reared in the laboratory on a variety of materials, decided that the small strain could be validly made a separate species, thus agreeing with Takahashi who, according to Floyd and Newsom (1960), had elevated this strain to species rank as Calandra sasakii. In conformity with modern North American usage Floyd and Newsom refer to this small species as Sitophilus sasakii (Tak.). In addition to differences in size, they found differences in the male and female genitalia, interstrain sterility and various ecological differences. There were also differences in pronotal markings as had been, according to Kono (1953), noted by Takahashi (1928). Kono states “…the adult of the large strain has pits dotted densely on the central part of the pronotum, the small strain does not, and, furthermore the shape and size of the pits differ distinctly”.

The Further Exploration of Applying Small-Strain and Large-Strain Formulations to SMA

2012 ◽  
Vol 529 ◽  
pp. 228-235
Author(s):  
Jie Yao ◽  
Yong Hong Zhu
Keyword(s):  
Phase Transformation ◽  
Constitutive Model ◽  
Uniaxial Tension ◽  
Driving Force ◽  
Research Team ◽  
Large Strain ◽  
Small Deformation ◽  
Small Strain ◽  
Proportional Loading ◽  
The Difference

Recently, our research team has been considering to applying shape memory alloys (SMA) constitutive model to analyze the large and small deformation about the SMA materials because of the thermo-dynamics and phase transformation driving force. Accordingly, our team use simulations method to illustrate the characteristics of the model in large strain deformation and small strain deformation when different loading, uniaxial tension, and shear conditions involve in the situations. Furthermore, the simulation result unveils that the difference is nuance concerning the two method based on the uniaxial tension case, while the large deformation and the small deformation results have huge difference based on shear deformation case. This research gives the way to the further research about the constitutive model of SMA, especially in the multitiaxial non-proportional loading aspects.

A Zebrafish Embryo Behaves both as a “Cortical Shell – Liquid Core” Structure and a Homogeneous Solid when Experiencing Mechanical Forces

2014 ◽  
Vol 20 (6) ◽  
pp. 1841-1847 ◽  
Author(s):  
Fei Liu ◽  
Dan Wu ◽  
Ken Chen
Keyword(s):  
Mechanical Properties ◽  
Mechanical Behavior ◽  
Zebrafish Embryo ◽  
Large Strain ◽  
Liquid Core ◽  
Small Strain ◽  
Core Structure ◽  
Mechanical Forces ◽  
Cortical Shell ◽  
A Cell

AbstractMechanical properties are vital for living cells, and various models have been developed to study the mechanical behavior of cells. However, there is debate regarding whether a cell behaves more similarly to a “cortical shell – liquid core” structure (membrane-like) or a homogeneous solid (cytoskeleton-like) when experiencing stress by mechanical forces. Unlike most experimental methods, which concern the small-strain deformation of a cell, we focused on the mechanical behavior of a cell undergoing small to large strain by conducting microinjection experiments on zebrafish embryo cells. The power law with order of 1.5 between the injection force and the injection distance indicates that the cell behaves as a homogenous solid at small-strain deformation. The linear relation between the rupture force and the microinjector radius suggests that the embryo behaves as membrane-like when subjected to large-strain deformation. We also discuss the possible reasons causing the debate by analyzing the mechanical properties of F-actin filaments.

scholarly journals DOMINANCE AND EPISTASIS IN HETEROSIS OF WHITE LEGHORN STRAIN CROSSES

1987 ◽  
Vol 67 (3) ◽  
pp. 663-680 ◽  
Author(s):  
R. W. FAIRFULL ◽  
R. S. GOWE ◽  
J. NAGAI
Keyword(s):  
Body Weight ◽  
Sexual Maturity ◽  
Egg Production ◽  
Significant Contribution ◽  
Production Traits ◽  
White Leghorn ◽  
Cross Combination ◽  
Commercial Strain ◽  
Better Than

Four unrelated pure strains of White Leghorns including a grandparent strain from industry and 12 two-strain, 24 three-strain, 24 four-strain and 12 F2 strain crosses produced contemporaneously were used to examine the role of dominance and epistasis in heterosis. A control strain and a commercial strain were also included. For egg weight, the heterosis observed closely approximated that expected due to dominance alone. For sexual maturity and body weight, dominance was the major component of heterosis, but epistasis made a significant contribution — additive by additive (A × A) genetic effects for sexual maturity and 140-d body weight, and parental epistasis for mature body weight. Both dominance and epistasis played a significant role in heterosis for egg production traits. A × A, dominance by dominance (D × D) and additive by dominance (A × D) epistasis were all important for hen-housed egg production and hen-housed egg yield. For hen-day rate of egg production, A × A epistasis was significant only early in the laying year (to 273 d), A × D and D × D were significant to 385 d and in the full year (to 497 d); however, none (A × A, A × D and D × D) was significant near the end of lay (386–497 d). Overall heterosis estimates for full year egg production measured as hen-housed egg production to 497 d or hen-day rate from housing to 497 d clearly showed that on average two-strain crosses were superior to three-strain crosses which were superior to four-strain crosses which in turn exceeded the F2 crosses. Nevertheless, several three-strain crosses had performance for egg production that was equal to or better than the two-strain cross with the highest egg production. Thus, in commerce, where the level of egg production is of great economic importance, the testing and use of a specific three-way cross combination will usually result in a better commercial product. Key words: Heterosis, egg production genetics, epistasis, stocking rate, strain cross, White Leghorn

scholarly journals Tilt and strain change during the explosion at Minami-dake, Sakurajima, on November 13, 2017

2021 ◽  
Author(s):  
Kohei Hotta ◽  
Masato Iguchi
Keyword(s):  
Ground Deformation ◽  
Large Strain ◽  
Phase 1 ◽  
Small Strain ◽  
Phase 2 ◽  
The North ◽  
Strombolian Eruption ◽  
Strain Change ◽  
Tilt Change

Abstract We herein propose an alternative model for deformation caused by an eruption at Sakurajima, which have been previously interpreted as being due to a Mogi-type spherical point source beneath Minami-dake. On November 13, 2017, a large explosion with a plume height of 4,200 m occurred at Minami-dake. During the three minutes following the onset of the explosion (November 13, 2017, 22:07–22:10 (Japan standard time (UTC+9); the same hereinafter), phase 1, a large strain change was detected at the Arimura observation tunnel (AVOT) located approximately 2.1 km southeast from the Minami-dake crater. After the peak of the explosion (November 13, 2017, 22:10–24:00), phase 2, a large deflation was detected at every monitoring station due to the continuous Strombolian eruption. Subsidence toward Minami-dake was detected at five out of six stations whereas subsidence toward the north of Sakurajima was detected at the newly installed Komen observation tunnel (KMT), located approximately 4.0 km northeast from the Minami-dake crater. The large strain change at AVOT as well as small tilt changes of all stations and small strain changes at HVOT and KMT during phase 1 can be explained by a very shallow deflation source beneath Minami-dake at 0.1 km below sea level (bsl). For phase 2, a deeper deflation source beneath Minami-dake at a depth of 3.3 km bsl was found in addition to the shallow source beneath Minami-dake which turned inflation after the deflation obtained during phase 1. However, this model cannot explain the tilt change of KMT. Adding a spherical deflation source beneath Kita-dake at a depth of 3.2 km bsl can explain the tilt and strain change at KMT and the other stations. The Kita-dake source was also found in a previous study of long-term ground deformation. Not only the deeper Minami-dake source MD but also the Kita-dake source deflated due to the Minami-dake explosion.

The relationship between crop size and egg production in Rhodnius prolixus

1986 ◽  
Vol 64 (12) ◽  
pp. 2654-2657 ◽  
Author(s):  
K. G. Davey ◽  
I.-K. Maimets ◽  
R. P. Ruegg
Keyword(s):  
Egg Production ◽  
Initial Rate ◽  
Important Determinant ◽  
Virgin Female ◽  
Corpus Allatum ◽  
Current Paper ◽  
Linear Rate ◽  
Crop Size ◽  
The Difference ◽  
The Relationship

Earlier work showed that the number of eggs produced by a virgin female is smaller than that produced by a mated female. The current paper shows that this results not from a difference in rates of egg production, but from the operation of the same linear rate for different times. Denervating the corpus allatum in virgin females extends the time over which the same rate of egg production operates, thus indicating that the inhibition of egg production in virgin females results from a nervous inhibition of the corpus allatum. The initial rate of emptying of the crop is also approximately linear in both virgin and mated females. Later, crop emptying slows in virgins and remains linear in mated females. When these relationships are disturbed by plugging the anus of females before feeding, the rate of crop emptying in virgins more closely resembles that in mated females, and the difference in egg production between mated and virgin females disappears. These results are put into the context of a hypothesis which predicts that the degree of distension of the crop is an important determinant of the length of time that the corpus allatum remains active.

scholarly journals Elastic Properties of Magnetorheological Elastomers in a Heterogeneous Uniaxial Magnetic Field

2018 ◽  
Vol 19 (10) ◽  
pp. 3045 ◽  
Author(s):  
Takehito Kikuchi ◽  
Yusuke Kobayashi ◽  
Mika Kawai ◽  
Tetsu Mitsumata
Keyword(s):  
Magnetic Field ◽  
Elastic Properties ◽  
Uniform Magnetic Field ◽  
Large Strain ◽  
Small Strain ◽  
Experimental Results ◽  
The Other ◽  
Magnetorheological Elastomers ◽  
Other Hand ◽  
Strain Model

Magnetorheological elastomers (MREs) are stimulus-responsive soft materials that consist of polymeric matrices and magnetic particles. In this study, large-strain response of MREs with 5 vol % of carbonyl iron (CI) particles is experimentally characterized for two different conditions: (1) shear deformation in a uniform magnetic field; and (2), compression in a heterogeneous uniaxial magnetic field. For condition (1), dynamic viscoelastic measurements were performed using a rheometer with a rotor disc and an electric magnet that generated a uniform magnetic field on disc-like material samples. For condition (2), on the other hand, three permanent magnets with different surface flux densities were used to generate a heterogeneous uniaxial magnetic field under cylindrical material samples. The experimental results were mathematically modeled, and the relationship between them was investigated. We also used finite-element method (FEM) software to estimate the uniaxial distributions of the magnetic field in the analyzed MREs for condition (2), and developed mathematical models to describe these phenomena. By using these practicable techniques, we established a simple macroscale model of the elastic properties of MREs under simple compression. We estimated the elastic properties of MREs in the small-strain regime (neo–Hookean model) and in the large-strain regime (Mooney–Rivlin model). The small-strain model explains the experimental results for strains under 5%. On the other hand, the large-strain model explains the experimental results for strains above 10%.

Investigation of Small- to Large-Strain Moduli Correlations of Rockfill Materials – Application to Romaine-2 Dam

2021 ◽  
Author(s):  
Ibrahim Lashin ◽  
Michael Ghali ◽  
Marc Smith ◽  
Daniel Verret ◽  
Mourad Karray
Keyword(s):  
Large Strain ◽  
Deformation Behaviour ◽  
Numerical Data ◽  
Small Strain ◽  
Hyperbolic Model ◽  
Large Strains ◽  
Initial Modulus ◽  
Rockfill Materials ◽  
Materials Used

Establishment of a relationship between the shear wave velocity (Vs) and other geotechnical parameters of rockfill soils at large strains (oedometer modulus, Moedo, tangent modulus, Et) is considered a significant step towards more precise modelling of earth-structure deformation behaviour. In this study, four samples of different gradations, reconstituted from the rockfill materials used in the construction of the Romaine-2 dam, were experimented to correlate the small strain to large strain moduli. Development of Moedo and Vs with consolidation was measured in the laboratory using the piezoelectric ring-actuator technique (P-RAT) incorporated in a large oedometer. Therefore, a correlation between Moedo and small strain shear modulus Go was proposed. Moreover, numerical simulations were performed based on the Duncan-Chang hyperbolic model to correlate the Vs to Duncan-Chang initial modulus(Ei). Based on the experimental and numerical data, a relation between Ei and Vs of the tested rockfill has been established. Verification studies were also carried out on in-situ measurements during Romaine-2 dam construction, proofing the ability of the proposed relationships to predict Ei related to the minor principal stress (σ3) from in-situ Vs measurement. The proposed correlations could help the geotechnical designers to estimate accurately the deformation of rockfill materials from in-situ Vs measurement.

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