Shell Volume Research Articles

Non-destructive measurements of egg parameters and quality characteristics

Non-destructive methods for assessing egg quality are used in the egg industry and in research on avian embryogenesis, incubation, selection programmes, genetics etc. According to the purpose for which they are being used, non-destructive methods have to meet certain requirements – rapid estimation of the results in the case of industrial use and high significance when used in research. In both cases minimum measurement of the initial parameters is preferable. In this review methods are considered that allow calculation of such egg variables as volume, surface area, shell weight, shell volume, shell density and thickness; weight, volume and density of egg contents; yolk and albumen weights; Haugh unit score and consistency of the interior; and strength characteristics of an egg that keep it intact.

Mathematical model for non-destructive calculation of the morphological prameters of avian eggs

The method for non-destructive calculation of the morphological parameters of avian eggs is proposed. Such variables as shell weight, thickness, and the density of egg interior may be defined by the formulae deduced using such initial data as egg weight, volume and length which may be measured in intact egg. To deduce the formulae the relationship between egg weight and every of the following parmneters as egg specific gravity, shape index (maximum diameter to length ratio), shell volume and shell density should be determined directly beforehand on a small sample of eggs. The obtained relationships are the initial data for simulating the set of all possible combinations of egg morphological parameters which may be found in nature.

Fragmentation phase transition in atomic clusters IV

Within the micro-canonical ensemble it is well possible to identify phase-transitions in small systems. The consequences for the understanding of phase transitions in general are discussed by studying three realistic examples. We present micro-canonical calculations of the fragmentation phase transition in Na-, K-, and Fe- clusters of N = 200 to 3000 atoms at a constant pressure of 1 atm. The transition is clearly of first order with a backbending micro-canonical caloric curve T P (E, V (E,P)) = {∂S(E, V (E,P))/∂E P}−1. From the Maxwell construction of βP (E/N,P) = 1/T P one can simultaneously determine the transition temperature T tr, the specific latent heat q lat, and the specific entropy-loss Δs surf linked to the creation of intra-phase surfaces. T trΔs surf*N/(4πr ws 2 N eff 2/3 ) = γ gives the surface tension γ. Here 4πr ws 2 N eff 2/3 = ΣN i*4πr ws 2 m i 2/3 is the combined surface area of all fragments with a mass m i ≥ 2 and multiplicity N i. All these characteristic parameters are for ∼1000 atoms similar to their experimentally known bulk values. This finding shows clearly that within micro-canonical thermodynamics phase transitions can unambiguously be determined without invoking the thermodynamic limit. However, one has carefully to distinguish observables which are defined for each phase-space point, like the values of the conserved quantities, from thermodynamic quantities like temperature, pressure, chemical potential, and also the concept of pure phases, which refer to the volume of the energy shell of the N-body phase-space and thus do not refer to a single phase-space point. At the same time we present here the first successful microscopic calculation of the surface tension in liquid sodium, potassium, and iron at a constant pressure of 1 atm.

An efficient, differentiable hydration potential for peptides and proteins

An approximate method for calculating the exposed volume of the hydration shell (VHS) about an atom, the Reduced Radius Independent Gaussian Sphere (RRIGS) approximation, is presented. A key ingredient in this method is the use of reduced van der Waals radii so that the error of including only double overlap terms (and omitting multiple overlap terms) in calculating the VHS is balanced by a reduction in the magnitude of the double overlap terms. Also, the double overlap is modeled with a gaussian function. The RRIGS approximate calculation of the VHS is shown to be very accurate (the rms deviation of the VHS of each atom in avian pancreatic polypeptide and bovine pancreatic trypsin inhibitor was 14.0 and 15.8 Å3, respectively, out of a range of values between 0 and 600 Å3). The RRIGS approximation is used to develop a potential function to represent the free energy of solvation for proteins. The pairwise gaussian form of the potential enables it to be incorporated into a gaussian representation of ECEPP (Empirical Conformational Energy Program for Peptides) for use in the Diffusion Equation Method (DEM) of global optimization. Inclusion of the effects of hydration by means of this potential is shown to require less than twice the computational time needed for computing the ECEPP conformational potential energy alone; this makes inclusion of solvent computationally feasible. Furthermore, this gaussian hydration potential function and its derivatives are continuous, so that it may be readily minimized. The combined potential of ECEPP/3 plus hydration is shown to require fewer energy evaluations per local minimization than ECEPP/3 alone for two small peptides. © 1996 by John Wiley & Sons, Inc.

Extensions of polyacrylic acid ammonium salts in the adsorption layer to fluidize alumina slurries

An average shell volume occupied in the adsorption layer on alumina by a polyacrylic acid ammonium salts molecule (PAA) defined as the average area occupied by an adsorbed PAA on alumina multiplied by the average thickness of the water layer at the limit of thickening, has been calculated from the adsorbed amount of PAA and from the flow points of alumina in the presence of PAA of different molecular weights. A steric effect of the PAA dispersant on the dispersion of alumina resulted in a flow with no yield stress. This was due to the change of the extension of PAA in the adsorption shell from a sphere to an ellipsoid with a long axis which exceeded the effective distance that the van der Waals attraction force reaches at a molecular weight for the PAA of between 10 000–20 000.

Phenotypical Improvement of Morphological Defences in the Mussel Mytilus edulis Induced by Exposure to the Predator Asterias rubens

Blue mussels, Mytilus edulis, were cultured in field enclosures in close vicinity of, and in absence of its predator, the starfish Asterias rubens. After four weeks, the morphology differed, such that predator-exposed mussels were significantly smaller in outer size (shell length, height and width), but had significantly larger posterior adductor muscle, thicker shell, and more meat per shell volume. These morphological changes suggested an improvement of the defences, which was confirmed in a predation assay where starfish needed significantly longer time to open predator-exposed mussels. The adaptive value was also demonstrated by a significantly larger survival of predator-exposed mussels in an assay where starfish foraged on a mixed population of exposed and control mussels. The experiment shows that predator-induced morphological plasticity exists in M. edulis. Such phenotypic plasticity may explain some of the morphological variation that is found in the field.

Pore Structural Analysis of Charcoals by Mercury Intrusion Porosimetry

Pore volume and macropore-size distribution of charcoal produced from the wood of a wide variety of trees were measured by mercury intrusion porosimetry and the following results were obtained.The shape of the distribution curve was remarkably dependent on wood type. Total pore volume of charcoal produced by carbonizing at high temperature was less than that of charcoal produced by carbonizing at low temperature. Total pore volume of coniferous tree charcoal exceeded that of broad-leaf tree charcoal. Total pore volume of molding charcoal wassmall, eventhough it came from the coniferous tree. Total pore volume of coconut shell charcoal and Kashioak charcoal was small, since these charcoal types are hard. The distribution curves of coconut shell, coconut shell charcoal, and coconut shell activated carbon were resemble, but the pore volume of the coconut shell was smaller than the others. Total pore volume increased in proportion to that of large pores.

Physiological ecology of a mussel with methanotrophic endosymbionts at three hydrocarbon seep sites in the Gulf of Mexico

In situ growth rates were determined, using two, 1-yr mark/recapture experiments, conducted between September 1991 and July 1993, for an undescribed mytilid, Seep Mytilid Ia, at three hydrocarbon seep sites in the Gulf of Mexico. The sites are located at depths of 540 to 730m, approximately 27°45′N; 91°30′W, and are separated by distances of 6 to 18 miles. These seep mytilids harbor methanotrophic endosymbionts and use methane as both a carbon and energy source. The mussel habitats were chemically characterized by analysis of water samples taken from precisely located microenvironments over, among and below the mussels, using small-volume, interstitial water samplers and the “Johnson Sea Link” submersible. Substantial differences were found in habital conditions, growth rates, and population structure for the mussels at the three sites examined. The growth rate of these seep mytilids reflects the methane concentration in their immediate habitat. Mussels at sites with abundant methane had growth rates that were comparable to shallow water mytilids at similar temperatures (5 to 8°C) with increases in shell length up to 17 mm yr−1 documented for smaller mussels (<40 mm shell length). In conjunction with measurements of growth rates, three condition indices (glycogen content, tissue water content, and the ratio of ash-free dry weight to shell volume) were used to determine the relationship between the condition of the mussels, their growth rates, and their habitat chemistry. The three condition indices were correlated with growth rate and were often significantly different between mussels in different samples.

Population structure, shell morphology, age and condition of the freshwater mussel Hyridella menziesi (Unionacea: Hyriidae) from seven lake and river sites in the Waikato River system

Populations of the freshwater mussel Hyridella menziesi were compared from six lakes and one river site along the Waikato River system, North Island, New Zealand. Estimated densities ranged from several hundred per square metre in Lake Taupo to less than one per square metre in Lake Karapiro. Length-frequencies were similar at all sites, with unimodal distributions and a notable absence of any individuals less than 20 mm long. The extent of shell erosion varied from sites where most mussels had less than 1% of the right valve affected (i.e., Ohakuri & Karapiro), to Lake Aratiatia where most shells had erosion over 1–20% of their surface. Taupo and Ohakuri mussels showed an unusually high incidence (over 50%) of internal shell abnormalities (including dulling, deformities and protuberances). Canonical discrimination based on shell length, height, width and weight clearly separated Taupo and Ohakuri mussels from all other sites, and ANCOVA on morphological characteristics confirmed significant differences between sites. Physical condition indices (based on dry flesh weight per shell weight and shell volume) showed an increasing downstream trend, but this was not significantly correlated with food availability (i.e., chlorophyll a concentration) because of unexpectedly low condition in lakes Ohakuri and Karapiro. Length v. age relationships contained considerable scatter and did not show between-site differences. Measured differences in external erosion, internal shell abnormalities and morphology were attributed to physical, chemical and biological factors. Use of mussels for environmental monitoring must take these ‘background’ differences into account.

A model for planktic foraminiferal shell growth

In this paper we analyze the laws of growth that control planktic foraminiferal shell morphology. We assume that isometry is the key toward the understanding of their ontogeny. Hence, our null hypothesis is that these organisms construct isometric shells. To test this hypothesis, geometric models of their shells have been generated with a personal computer. It is demonstrated that early chambers in log-spirally coiled structures cannot follow a strict isometric arrangement. In the real world, the centers of juvenile chambers deviate from the logarithmic growth curve. Juvenile stages are generally more planispiral and contain more chambers per whorl than adult stages. These traits are shown to be essential in order to keep volumes of consecutive chambers in geometric progression. We are convinced that the neanic stage marks the constructional bridge from a juvenile set of growth parameters to an adult one. The adult stage can be strictly isometric, that is, the effective shape is constant and the increase in volume after a chamber addition is proportional to the preexisting volume of the shell.The shell volume is related to the biomass, the ratio of outer shell surface area to shell volume is related to the respiration rate and the ratio of the total shell surface area to shell volume is related to the total calcification effort. The influence of the parameters of the model on these relationships is investigated. Only the initial radius and the rate of radius increase affect the relationships between shell volume and surface area. The other shape parameters merely provide a fine tune-up of these relationships. Size itself plays a major role during foraminiferal development.

Factors Affecting the Shell Assessment Behaviour of the Hermit Crab, Calcinus Tibicen (Herbst, 1791) (Decapoda, Paguridea)

Factors influencing shell assessment behaviour were studied in the hermit crab, Calcinus tibicen. Visual and chemical presence of potential competition significantly lengthened the duration of shell assessment. Shell genus occupied by the hermit crab also had a significant effect. Those in Astrea shells examined an offered Cerithium shell significantly longer than hermit crabs occupying Gerithium, Pisania, or Nerita shells. Shell deficit, the difference between optimal shell volume for the hermit crab and actual shell volume, did not have a significant effect on the behavior of the hermit crabs occupying Cerithium shells. For those in Pisania shells there was a negative correlation between shell deficit and shell examination; while crabs in Nerita and Astrea shells demonstrated a positive correlation between shell deficit and shell examination. Neither the sex of the individual crab nor the presence of a predator, Calappa flammea, had a significant effect on shell assessment behaviour.

Bridging of colloidal particles through adsorbed polymers

Colloidal silica particles have been dispersed in an aqueous solution of poly(ethylene oxide) macromolecules. The macromolecules adsorb on the silica surfaces and modify the interactions between silica particles. The outer thickness of the adsorbed polymer layers has been determined from changes in the viscosity of the dispersion. Forsaturated layers on large particles this thickness equals the free solution radius of the macromolecules; with small particles the volume of the polymer shell is the same, and the thickness is reduced accordingly.Unsaturated layers are collapsed on the particle surfaces; when such unsaturated layers extend beyond the range of electrostatic repulsions they cause the particles to flocculate.

Calculation of the VIB-rotational state density of polyatomic molecules by adiabatic switching

The problem of estimating the vibrational and vib-rotor state density (both local and cumulative) for polyatomic molecules is approached using the Hertz invariant of classical Hamiltonian dynamics. Such state densities are key input to statistical theoreis of reaction dynamics such as that of RRKM and transition-state theory (TST), and have recently found to be seriously under-estimated by standard Harmonic and direct count Morse oscillator methods. In the semi-classical limit (which is quite appropriate for the very high state densities of interest here) the cumulative state density at energy E is simply the volume of the energy shell, V( E), divided by h N , h being Planck's constant, and N the number of degrees of freedom. The local state density is then h −N d V( E)/d E. Use may thus be made of the fact, noted by Hertz, that the energy shell is an adiabatic invariant for ergodic Hamiltonian systems. This invariance, combined with the time-dependent version of Liouville's theorem allows rigorous estimation of the phase volume of ergodic Hamiltonian systems which are adiabatically connected to other ergodic systems of known phase volume. As such ergodic reference systems with known phase volume are not easily found, we show that, when taken as an averaging method, the Hertz invariant gives excellent results when the reference Hamiltonian is not only non-ergodic, but in fact is separable. Thus, using an N degree of freedom isotropic oscillator reference, classical adiabatic switching is shown to give cumulative and local state densities for a model system with numbers of degrees of vibrational freedom ranging from 4, 6, 8…20… and finally up to 1000. In the regime beyond 8 degrees of freedom primitive Monte-Carlo sampling is inapplicable in a practical sense.

Scaling patterns in the Antarctic brachiopod Liothyrella uva (Broderip, 1833)

Scaling patterns of shell thickness, shell volume, total animal volume, internal tissue volume and mantle cavity volume in the brachiopod Liothyrella uva (Broderip, 1833) were investigated in relation to shell length. Exponents from double logarithmic regressions were 0.66, 2.77, 3.12, 3.06 and 3.34, respectively. The coefficients 3.12 and 3.06 were not significantly different from a cubic relationship, but the exponents 2.77 (shell volume) and 3.34 (mantle cavity volume) were different from 3.00. The amount of shell material, therefore decreases in relation to other brachiopod tissues as animals grow, while the mantle cavity gets relatively larger. These results suggest that large brachiopods may suffer space constraints because of the volume needed to house the lophophore and this has implications for all aspects of the brachiopods life style. Data on ash-free dry weight (AFDW) assessments of shells from an early winter sample showed a slope of 2.78, which is consistent with the shell volume relationship. A sample from mid summer, however, produced a relationship which was different in large and small animals. In individuals < 31.3 mm in length the exponent was 2.73 (which was indistinguishable from the 2.78 for the winter sample); however, the exponent was 3.73 for animals greater than this. 31.3 mm was also the minimum length of brooding females in this study. These data indicate that the function of caeca changes when brachiopods become reproductive.

The size variable and allometric analysis in the barnacle genusBalanus

Size variables employed in field and laboratory studies on acorn barnacles usually vary with each investigation, making accurate comparisons of results among studies difficult. The relationship of a size index to individual weight or volume is either not known, or not reported. Evaluation of 15 morphometric variables by allometric analysis, using least-squares regression, multiple step-wise regression and ANCOVA, was performed on adults of 12 species of the cosmopolitan genus Balanus. Specimens represent variation in size, shell shape, and shell design thought to occur in the genus; only isolated, complete, undamaged individuals growing on planar surfaces were used. By significance testing, within and among species, total shell volume (VTS) and basal length (LBA) increase in constant proportion with total weight, but valve weight (WTV) and soma weight (TSO) do not. Regression statistics for log-linearized data permit a discussion of other attributes which characterize these variables.

Recommendations for Quantitation of the Left Ventricle by Two-Dimensional Echocardiography

We have presented recommendations for the optimum acquisition of quantitative two-dimensional data in the current echocardiographic environment. It is likely that advances in imaging may enhance or supplement these approaches. For example, three-dimensional reconstruction methods may greatly augment the accuracy of volume determination if they become more efficient. The development of three-dimensional methods will depend in turn on vastly improved transthoracic resolution similar to that now obtainable by transesophageal echocardiography. Better resolution will also make the use of more direct methods of measuring myocardial mass practical. For example, if the epicardium were well resolved in the long-axis apical views, the myocardial shell volume could be measured directly by the biplane method of discs rather than extrapolating myocardial thickness from a single short-axis view. At present, it is our opinion that current technology justifies the clinical use of the quantitative two-dimensional methods described in this article. When technically feasible, and if resources permit, we recommend the routine reporting of left ventricular ejection fraction, diastolic volume, mass, and wall motion score.

An Evaluation of Active Noise Control in a Cylindrical Shell

This paper examines the physical mechanisms governing the use of active noise control in an extended volume of a cylindrical shell. Measured data were compared with computed results from a previously derived analytical model based on infinite shell theory. For both the analytical model and experiment, the radiation of external monopoles is coupled to the internal acoustic field through the radial displacement of the thin, elastic, cylindrical shell. An active noise control system was implemented inside the cylinder using a fixed array of discrete monopole sources, all of which lie in the plane of the exterior noise sources. Good agreement between measurement and prediction was obtained for both internal pressure response and overall noise reduction. Attenuations in the source plane greater than 15 dB were recorded along with a uniformly quieted noise environment over an indicative length inside the experimental model. Results indicate that for forced responses with extended axial distributions, axial arrays of control sources may be required. Finally, the Nyquist criteria for the number of azimuthal control sources is shown to provide for effective control over the full cylinder cross section.

Optical imagery and spectrophotometry of CTB 80

Narrow-band imagery and spectrophotometry of the central region of CTB 80 are presented. The images show weak forbidden O III and ubiquitous filamentary forbidden S II and H-alpha emission from the extended radio lobes in which the core is embedded. The data indicate that the extended component is shock heated. Balmer line-dominated emission is observed around the perimeter of the core. Assuming that the volume of the radio shell is similar to the volume of the thermal shell, it is found that a magnetic field of about 600 microG and a cosmic-ray proton-to-electron ratio of about 200 are required to explain the pressure and synchrotron volume emissivity in the radio shell. It is suggested that the optical emission form the core of CTB 80 arises behind shocks which are being driven into a magnetized thermal plasma by the confined relativistic wind from PSR 1951+32.

Shell exchanges in the hermit crab Calcinus tibicen

Shell exchange interactions of individuals of the hermit crab Calcinus tibicen were examined to see if these crabs behaved in a pattern which was similar to that observed in other species. Multiple regression analyses indicated that crab weight and shell internal volume were the best and sufficient estimators of crab and shell sizes. The model of exchange which best predicted the outcomes of naturally occurring interactions with the fewest parameters was the negotiations model (exchange should occur only if both participants gain in shell fit) using shell volume as the shell size parameter. Models which incorporated shell species considerations or both negotiations and aggressive elements increased the predictive powers, and overall the outcomes of 87% of the 202 shell exchange interactions of C. tibicen were predicted correctly.

Littoral Stratification in Growth form and Fecundity of the Rock Barnacle, Semibalanus Balanoides

The population dynamics of rock barnacles, Semibalanus balanoides (L.), residing in low and high intertidal zones are affected by conspicuously different factors. The barnacle population in the high intertidal zone tends to show longterm stability due to a low incidence of both predation and interspecific competition. Wave exposure, desiccation and intraspecific competition are more important factors affecting abundance and size distribution in this zone (Menge, 1976). In the low intertidal zone, barnacle predation by the dogwhelk, Nucella lapillus (L.) is intense (Menge, 1976) and both the adults and larvae are smaller than in the high intertidal zone (Barnes, 1953). The growth form of S. balanoides is density dependent with taller, more columnar individuals predominating at high densities and short conical barnacles at low densities. Lower fecundity of conical individuals may be due to lower internal shell volume compared with columnar forms (Wethey, 1984). Fecundity increases both with increasing age and base length (Arnold, 1977) and is positively density dependent (Wethey, 1984).