Gynogenetic diploids were produced from the eggs of natural tetraploid loach Misgurnus anguillicaudatus (Pisces: Cobitidae) without any manipulation for chromosome duplication. When eggs of a four-year-old diploid gynogenetic individual were fertilized with spermatozoa of specimens from normal diploid and natural tetraploid lines, viable diploid and triploid progeny were produced, respectively. Thus, egg nucleus of the diploid gynogen is haploid. In the gonads of diploid progeny, diploid (2n = 50) and tetraploid (4n = 100) mitotic metaphases were observed. The majority of oocytes (76%) showed regular 25 bivalents as in normal diploids, but the other 16% showed a few univalents. The remaining 8% exhibited about 50 bivalents, suggesting chromosome duplication by premeiotic endomitosis. In the testes, a few spermatocytes (6%) showed normal 25 bivalents, but 86% contained various number of univalents and the remaining 8% contained about 50 bivalents. No peaks of spermatozoa were identified in the testis by flow cytometry. In the triploid progeny, triploid (3n = 75) and hexaploid (6n = 150) mitotic metaphases were observed in both ovaries and testes. Most meiotic figures (about 90%) contained approximately 25 bivalents and 25 univalents in both sexes; the rest contained approximately 75 or more bivalents. Spermatozoa were not identified in the testis by flow cytometry. Thus, the diploid males between the diploid gynogens and common diploid, and both sexes of triploids between the diploid gynogens and tetraploid, show aberrant meioses such as frequent formation of univalents, but the diploid females seem to be less affected.
The inhibitory potential of primary and secondary reproductives was studied using half-orphaned colonies of Kalotermes flavicollis. Both primary and secondary reproductives (neotenics) were equally effective in inhibiting the development of replacement reproductives. Single females totally inhibited the development of female secondary reproductives but did not affect the development of male secondary reproductives. Single males had neither a stimulatory nor inhibitory effect on the development of secondary reproductives. The inhibitory ability of pairs of primary reproductives shortly after dealation and at the stage of incipient colony formation (couple with the first batch of eggs) was also examined. While pairs of freshly dealated reproductives were not able to inhibit the development of neotenics, pairs of primary reproductives that had their first batch of eggs, fully inhibited the development of neotenics.
This paper aims to provide a comprehensive survey of phrasal and clausal comparative constructions in the N. W. Caucasian language Abkhaz (in relation to data from the standard, Abzhywa dialect). Following the lead of Knecht (1976), the following three terms will be used throughout this article: (a) Remainder = in the phrasal comparative, a single NP (preceded by “than” in English); in the clausal comparative, the remains of the clause; (b) Trigger = the quantified constituent in the controlling clause; (c) Target = the compared constituent in the comparative clause obligatorily deleted by Comparative Deletion.
Extracellular single unit activity in the intralaminar thalamic nuclei (ncl. centralis lateralis, CL, n = 77 and ncl. parafascicularis, Pf, n = 163) and in the pretectal area (Pt, n = 75) was examined following chronic electrolytic lesions of the nucleus reticularis thalami (nRT) in ketamine-anaesthetized rats after single electrical stimuli to the ventrobasal complex (VB). Extensive alterations of either the ongoing ("spontaneous") activity or the pattern of VB evoked responses were observed. Four major changes were observed in the activity of these intralaminar or pretectal neurones: 1) many neurones were silent, two times more frequently than in a parallel study with control intact rats; 2) the firing pattern of all the other neurones was in the form of tonic (stationary-like) discharge, without burst discharges as previously described in intact animals. They were ranked into classes according to their spontaneous discharge: class I, silent (no resting discharge) 12 %, class II (1-15 Hz), 54 % and class III (> 16 Hz), 34 %. Class III neurones were never found in intact rats; 3) electrical stimulation of the VB evoked a short latency orthodromic excitatory response in these neurones but this response was not followed by any slowing or depression of the spontaneous activity in more than 40 % of recorded cells. When it occurred, this pause was shorter than that always observed in intact rats by more than 35 % and longer in 7 % of the responsive cells. All these changes were correlated with the extent of damage to the ipsilateral nRT; 4) VB stimulation evoked prolonged excitatory responses lasting more than 150 ms in 13 % of the responsive cells, and nRT stimulation led to a short latency response followed by a pause of activity. These findings suggest that the nRT is involved in sensory integration and modulation.
We propose results about sign-constancy of Green's functions to impulsive nonlocal boundary value problems in a form of theorems about differential inequalities. One of the ideas of our approach is to construct Green's functions of boundary value problems for simple auxiliary differential equations with impulses. Careful analysis of these Green's functions allows us to get conclusions about the sign-constancy of Green's functions to given functional differential boundary value problems, using the technique of theorems about differential and integral inequalities and estimates of spectral radii of the corresponding compact operators in the space of essential bounded functions.
In this essay the author reflects on the subject of state-building, its interpretation and impact on the society. The government usually understands state-building differently than the opposition. The question is raised whether the development does not lead from state-building to “herd-building”, when smaller and larger groups behave like an easy-to-manipulate herd. But how can we revert this process?
We offer the quantitative estimation of stability of risk-sensitive cost optimization in the problem of optimal stopping of Markov chain on a Borel space X. It is supposed that the transition probability p(⋅|x), x∈X is approximated by the transition probability p˜(⋅|x), x∈X, and that the stopping rule f˜∗ , which is optimal for the process with the transition probability p˜ is applied to the process with the transition probability p. We give an upper bound (expressed in term of the total variation distance: supx∈X∥p(⋅|x)−p˜(⋅|x)∥) for an additional cost paid for using the rule f˜∗ instead of the (unknown) stopping rule f∗ optimal for p.