3,309 research outputs found
A Technique for Physiologically Age-Grading Female Stable Flies, Stomoxys calcitrans (L.)
A method of dissection followed by staining was initiated to allow physiological age- grading based on ovarian development in order to more completely describe the physiological development of adult female stable flies [Stomoxys calcitrans (L. )]. The gonotrophic developmental continuum from a non-differentiated cell in teneral females to mature eggs at the time of oviposition was first arbitrarily divided into six stages by using distinct landmarks within the developing oocyte . Then, nulliparous, uniparous, and biparous+ females were differentiated on the basis of the presence or absence of stained follicular relics in the ovariole sheaths. The combination of the two techniques made it possible to assign dissected adult female stable flies to one of 12 age-classes
Electrodic processes of derivatives of 2,2,4,4-tetramethylpentane on stationary solid electrodes 1. : Cyclic voltammetry of 3-hydrazones of 2,2,4,4 - tetramethylpentane
Evaluation of minor pathogen intramammary infection, susceptibility parameters, and somatic cell counts on the development of new intramammary infections with major mastitis pathogens
A storage and access architecture for efficient query processing in spatial database systems
Due to the high complexity of objects and queries and also due to extremely
large data volumes, geographic database systems impose stringent requirements on their
storage and access architecture with respect to efficient query processing. Performance
improving concepts such as spatial storage and access structures, approximations, object
decompositions and multi-phase query processing have been suggested and analyzed as
single building blocks. In this paper, we describe a storage and access architecture which
is composed from the above building blocks in a modular fashion. Additionally, we incorporate
into our architecture a new ingredient, the scene organization, for efficiently
supporting set-oriented access of large-area region queries. An experimental performance
comparison demonstrates that the concept of scene organization leads to considerable
performance improvements for large-area region queries by a factor of up to 150
An examination of the character of isabel archer from henry james\u27 the portrait of a lady
The purpose of this thesis is to examine the character of Isabel Archer, the protagonist of the Portrait of a Lady by Henry James. The subject of the novel is the journey of Isabel Archer from ignorance, illusions, and independence to understanding, realities, and a sense of duty
Relative velocities among accreting planetesimals in binary systems: the circumprimary case
We investigate classical planetesimal accretion in a binary star system of
separation ab<50AU by numerical simulations, with particular focus on the
region at a distance of 1 AU from the primary. The planetesimals orbit the
primary, are perturbed by the companion and are in addition subjected to a gas
drag force. We concentrate on the problem of relative velocities dv among
planetesimals of different sizes. For various stellar mass ratios and binary
orbital parameters we determine regions where dv exceed planetesimal escape
velocities v_esc (thus preventing runaway accretion) or even the threshold
velocity v_ero for which erosion dominates accretion. Gaseous friction has two
crucial effects on the velocity distribution: it damps secular perturbations by
forcing periastron alignment of orbits, but at the same time the
size--dependence of this orbital alignment induces a significant dv increase
between bodies of different sizes. This differential phasing effect proves very
efficient and almost always increases dv to values preventing runaway
accretion, except in a narrow domain of almost circular companion orbits. The
erosion threshold dv>v_ero is reached in a wide (ab,eb) space for small (<10km)
planetesimals, but in a much more limited region for bigger ~50km objects. In
the intermediate v_esc<dv < v_ero domain, a possible growth mode would be the
type II runaway growth identified by Kortenkmap et al.(2001)Comment: to appear in Icarus (accepted 30 january 2006
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