Contribution à l'étude de la ptérylose chez Perisoreus canadensis (Linnaeus), (Aves : Corvidae)

1971 ◽  
Vol 49 (2) ◽  
pp. 147-158
Author(s):  
Henri Ouellet

The pterylosis of the Corvidae is generally not well known. The purpose of the present study is to describe the pterylography of the gray jay (Perisoreus canadensis). A French terminology is proposed for the various elements of the feather tracts and for the apteria. Down is present on the apteria of the winter individuals examined. The circles of feathers around the eyes are considered as feather tracts rather than elements of the other head feather tracts. There is no median fissure in the dorsal saddle, and the posterior element of the dorsal feather tract is attached to the saddle by a narrow band of feathers. There are 20 remiges; the 10th secondary is reduced in size and difficult to identify on study skins. The arrangement, shape, and orientation of the wing coverts are discussed. There are 12 rectrices, 6 on each side, but there are only 10 upper-tail coverts; a pair of filoplumes corresponds to each of them. Twelve (12) greater under tail coverts were found. A description of the natal down is provided. Individual variation in the pterylosis of the gray jay is slight, and there appears to be no sexual dimorphism; similarly, the bilateral symmetry is very high, perhaps perfect. Finally, it is suggested that the presence of down on the apteria in winter may be an adaptation to the low winter temperatures in the range of the species, and to breeding early in cold climate.

Perception ◽  
1996 ◽  
Vol 25 (7) ◽  
pp. 757-771 ◽  
Author(s):  
Peter Wenderoth

Detection of vertical bilateral symmetry has previously been studied in patterns composed of black or white dots on a grey background under four conditions: (a) same contrast (black or white) for all dots (called BB or WW, for ‘all black or all white’); (b) half of the dots black and half white with positive correspondence between symmetrical dot pairs (called MA for ‘matched’); (c) half of the dots black and half white with negative correspondence between symmetrical dot pairs (called OPP for ‘opposite’); and (d) black (white) dots on one side of the axis and white (black) dots on the other (called BW for ‘one side black the other white’). It was found that performance was ordered BB (or WW) = MA > OPP =BW, where > indicates better performance. That experiment was repeated here in experiment 1 with symmetry axes not only at vertical but also at horizontal and the two diagonals. It was found overall that BB = MA > OPP, BW. However, OPP > BW when random trials were included in the analysis but when they were excluded BW > OPP. This was due to a very high false-alarm rate in condition BW which could be accounted for if grouping by colour occurs prior to symmetry detection. In experiment 2 it was shown that vertical-symmetry salience over other orientations remained about the same as OPP patterns progressively changed into BB patterns by varying the percentage same polarity between 0% and 100% in 12%–13% steps. Thus, dot-pair polarity affects performance without affecting relative axis salience, as was also found recently when dot pattern outlines were masked. All of the data indicate that although opposite dot polarity does reduce performance slightly, the symmetry-detection mechanism is remarkably resilient to such perturbation. The high false-alarm rate in the BW condition of experiment 1 may be accounted for by extremely salient global grouping of dots by luminance which effectively creates an integral stimulus which is perceptually difficult to break down into its component dot pairs, prohibiting the required point-by-point matching necessary to reject symmetry detection. The small detrimental effect of nonmatched polarity might be due to the polarity differences masking the grouping of dots into ‘clumps’ on either side of the axis, a process for which there is a great deal of independent evidence.


1979 ◽  
Author(s):  
J. G. Kelton ◽  
P. B. Neame ◽  
I. Walker ◽  
A. G. Turpie ◽  
J. McBride ◽  
...  

Thrombotic thrombocytopenic purpura (TTP) is a rare but serious illness of unknown etiology. Treatment by plasmapheresis has been reported to be effective but the mechanism for benefit is unknown. We have investigated the effect of plasmapheresis in 2 patients with TTP by quantitating platelet associated IgG (PAIgG) levels prior to and following plasmapheresis. Both patients had very high levels of PAIgG at presentation (90 and A8 fg IgG/platelet respectively, normal 0-5). in both, the PAIgG levels progressively fell to within the normal range and the platelet count rose following plasmapheresis. One patient remained in remission with normal platelet counts and PAIgG levels. The other relapsed after plasmapheresis and the PAIgG level rose prior to the fall in platelet count. Plasmapheresis was repeated and resulted in normalization of both the platelet count and PAIgG level. It is suggested that plasmapheresis removes antiplatelet antibody or immune complexes which may be of etiological importance in this illness.


Author(s):  
I. R. Khuzina ◽  
V. N. Komarov

The paper considers a point of view, based on the conception of the broad understanding of taxons. According to this point of view, rhyncholites of the subgenus Dentatobeccus and Microbeccus are accepted to be synonymous with the genus Rhynchoteuthis, and subgenus Romanovichella is considered to be synonymous with the genus Palaeoteuthis. The criteria, exercising influence on the different approaches to the classification of rhyncholites, have been analyzed (such as age and individual variability, sexual dimorphism, pathological and teratological features, degree of disintegration of material), underestimation of which can lead to inaccuracy. Divestment of the subgenuses Dentatobeccus, Microbeccus and Romanovichella, possessing very bright morphological characteristics, to have an independent status and denomination to their synonyms, has been noted to be unjustified. An artificial system (any suggested variant) with all its minuses is a single probable system for rhyncholites. The main criteria, minimizing its negative sides and proving the separation of the new taxon, is an available mass-scale material. The narrow understanding of the genus, used in sensible limits, has been underlined to simplify the problem of the passing the view about the genus to the other investigators and recognition of rhyncholites for the practical tasks.


1994 ◽  
Vol 29 (7) ◽  
pp. 327-333
Author(s):  
Y. Matsui ◽  
F. Yamaguchi ◽  
Y. Suwa ◽  
Y. Urushigawa

Activated sludges were acclimated to p-nitrophenol (PNP) in two operational modes, a batch and a continuous. The operational mode of the PNP acclimation of activated sludges strongly affected the physiological characteristics of predominant microorganisms responsible for PNP degradation. Predominant PNP degraders in the sludge in batch mode (Sludge B) had lower PNP affinity and were relatively insensitive to PNP concentration. Those of the sludge in continuous mode (Sludge C), on the other hand, had very high PNP affinity and were sensitive to PNP. MPN enumeration of PNP degraders in sludge B and C using media with different PNP concentrations (0.05, 0.2,0.5 and 2.0 mM) supported the above results. Medium with 0.2 mM of PNP did not recover PNP degraders in sludge C well, while it recovered PNP degraders in sludge B as well as the medium with 0.05 mM did. When switching from one operational mode to the other, the predominant population in sludge B shifted to the sensitive group, but that of sludge C did not shift at the given loading of PNP, showing relative resistance to inhibitive concentration.


2019 ◽  
Vol 11 (3) ◽  
pp. 328-341
Author(s):  
Rifki Ismal ◽  
Nurul Izzati Septiana

Purpose The demand for Saudi Arabian real (SAR) is very high in the pilgrimage (hajj) season while the authority, unfortunately, does not hedge the hajj funds. As such, the hajj funds are potentially exposed to exchange rate risk, which can impact the value of hajj funds and generate extra cost to the pilgrims. The purpose of this paper is to conduct simulations of Islamic hedging for pilgrimage funds to: mitigate and minimize exchange rate risk, identify and recommend the ideal time, amount and tenors of Islamic hedging for hajj funds, estimate cost saving by pursuing Islamic hedging and propose technical and general recommendations for the authority. Design/methodology/approach Forward transaction mechanism is adopted to compute Islamic forward between SAR and Rupiah (Indonesian currency) or IDR. Findings – based on simulations, the paper finds that: the longer the Islamic hedging tenors, the better is the result of Islamic hedging, the decreasing of IDR/USD is the right time to hedge the hajj funds and, on the other hand, the IDR/SAR appreciation is not the right time to hedge the hajj funds. Findings Based on simulations, the paper finds that: the longer the Islamic hedging tenors, the better is the result of Islamic hedging, the decreasing of IDR/USD is the right time to hedge the hajj funds and, on the other hand, the IDR/SAR appreciation is not the right time to hedge the hajj funds. Research limitations/implications The research suggests the authority to (and not to) hedge the hajj fund, depending on economic conditions and market indicators. Even though the assessment is for the Indonesian case, other countries maintaining hajj funds might also learn from this paper. Originality/value To the best of author’s knowledge, this is the first paper in Indonesia that attempts to simulate the optimal hedging of hajj funds.


2021 ◽  
Vol 7 (s2) ◽  
Author(s):  
Irmtraud Kaiser ◽  
Andrea Ender

Abstract This paper explores intra-individual variation as a manifestation of language-internal multilingualism in the Central-Bavarian Austrian context. Based on speech data from children and adults in different contexts, we discuss different methods of measuring and analyzing inter-situational variation along the dialect and standard language spectrum. By contrasting measures of dialectality, on the one hand, and proportions of turns in dialect, standard language or intermediate/mixed forms on the other, we gain complementary insights not only into the individual dialect-standard repertoires but also into the consequences of different methodological choices. The results indicate that intra-individual variation is ubiquitous in adults and children and that individual repertoires need to be taken into account from the beginning of the language acquisition process. We suggest that while intra-individual variation can be attested through the use of various methods, the revealed level of granularity and the conclusions that can be drawn as to the individual repertoires on the dialect-standard spectrum largely depend on the measures used and their inherent assumptions and intrinsically necessary categorizations.


2005 ◽  
Vol 495-497 ◽  
pp. 603-608 ◽  
Author(s):  
Atsushi Todayama ◽  
Hirosuke Inagaki

On the basis of Taylor-Bishop-Hill’s theory, many previous theoretical investigations have predicted that, at high rolling reductions, most of orientations should rotate along theβfiber from {110}<112> to {123}<634> and finally into the {112}<111> stable end orientations. Although some exceptions exist, experimental observations have shown, on the other hand, that the maximum on the β fiber is located still at about {123}<634> even after 97 % cold rolling. In the present paper, high purity Al containing 50 ppm Cu was cold rolled up to 99.4 % reduction in thickness and examined whether {112}<111> stable end orientation could be achieved experimentally. It was found that, with increasing rolling reduction above 98 %, {110}<112> decreased, while orientations in the range between {123}<634> and {112}<111> increased, suggesting that crystal rotation along the βfiber from {110}<112> toward {123}<634> and {112}<111> in fact took place. At higher rolling reductions, however, further rotation of this peak toward {112}<111> was extremely sluggish, and even at the highest rolling reduction, it could not arrive at {112}<111>. Such discrepancies between theoretical predictions and experimental observations should be ascribed to the development of dislocation substructures, which were formed by concurrent work hardening and dynamic recovery. Since such development of dislocation substructures are not taken into account in Taylor-Bishop-Hill’s theory, it seems that they can not correctly predict the development of rolling textures at very high rolling reductions, i. e. stable end orientations. On annealing specimens rolled above 98 % reduction in thickness, cube textures were very weak, suggesting that cube bands were almost completely rotated into other orientations during cold rolling. {325}<496>, which lay at an intermediate position between {123}<634> and {112}<111> along theβfiber, developed strongly in the recrystallization textures.


1953 ◽  
Vol 31 (2) ◽  
pp. 171-181 ◽  
Author(s):  
D. W. R. McKinley ◽  
Peter M. Millman

In the course of the Ottawa meteor program some unusual echoes have been detected on 33 Mc. Echoes from the aurora are discussed and correlated with visual observations. Two mechanisms of radio reflections from the aurora have been proposed but the data here presented are insufficient to favor one over the other. On Aug. 4, 1948, six extremely long duration meteor echoes were observed which may have been due to abnormal ionospheric conditions. From time to time since August, 1948, a weak semipermanent echo has been recorded, usually appearing at a range of about 80 km., and enduring up to an hour. It is suggested that this echo is due to back-scatter from the same sources in the lower E-region that are presumed to be responsible for long-range very high frequency propagation.


Genetics ◽  
1996 ◽  
Vol 143 (1) ◽  
pp. 353-364 ◽  
Author(s):  
Jerry A Coyne

Abstract Females of Drosophila melanogaster and its sibling species D. simulans have very different cuticular hydrocarbons, with the former bearing predominantly 7,11-heptacosadiene and the latter 7-tricosene. This difference contributes to reproductive isolation between the species. Genetic analysis shows that this difference maps to only the third chromosome, with the other three chromosomes having no apparent effect. The D. simulans alleles on the left arm of chromosome 3 are largely recessive, allowing us to search for the relevant regions using D. melanogaster deficiencies. At least four nonoverlapping regions of this arm have large effects on the hydrocarbon profile, implying that several genes on this arm are responsible for the species difference. Because the right arm of chromosome 3 also affects the hydrocarbon profile, a minimum of five genes appear to be involved. The large effect of the third chromosome on hydrocarbons has also been reported in the hybridization between D. simulans and its closer relative D. sechellia, implying either an evolutionaly convergence or the retention in D. sechllia of an ancestral sexual dimorphism.


2021 ◽  
Vol 60 (3-4) ◽  
pp. 363-398

Abstract The Roman father and son of the same name, P. Decius Mus, became paragon heroes by deliberately giving their lives in battle that Rome might win over a fierce enemy. Both engaged in a special ritual called devotio (from which our word “devotion” derives) to offer themselves to the gods of the Underworld, with whom regular people have very little interaction and to whom they rarely sacrifice. While the Mus family is the most famous for this act, it turns out the willingness to sacrifice oneself for Rome frequently occurs within stories of great patriots, including the story of Horatius Cocles, Mettius Curtius, Atilius Regulus, and even the traitors Coriolanus and Tarpeia. Romans regarded self-sacrifice as a very high, noble endeavor, whereas they loathed and persecuted practitioners of human sacrifice. It is therefore quite amazing to read that the Romans thrice engaged in state-sponsored human sacrifice, a fact they rarely mention and generally forget. The most famous enemy practitioners of human sacrifice were the Druids, whom the Romans massacred on Mona Island on Midsummer Night's Eve, but the Carthaginians, the Germans, the Celts, and the Thracians all infamously practiced human sacrifice. To Romans, the act of human sacrifice falls just short of cannibalism in the spectrum of forbidden practices, and was an accusation occasionally thrown against an enemy to claim they are totally barbaric. On the other hand, Romans recognized their own who committed acts of self-sacrifice for the good of the society, as heroes. There can be no better patriot than he who gives his life to save his country. Often the stories of their heroism have been exaggerated or sanitized. These acts of heroism often turn out to be acts of human sacrifice, supposedly a crime. It turns out that Romans have a strong legacy of practicing human sacrifice that lasts into the historic era, despite their alleged opposition to it. Numerous sources relate one story each. Collecting them all makes it impossible to deny the longevity of human sacrifice in Rome, although most Romans under the emperors were probably unaware of it. The paradox of condemning but still practicing human sacrifice demonstrates the nature of Roman religion, where do ut des plays a crucial role in standard sacrifice as well as in unpleasant acts like human sacrifice. Devotio was an inverted form of sacrifice, precisely because it was an offering to the gods of the Underworld, rather than to Jupiter or the Parcae. Romans may have forsaken devotio, but they continued to practice human sacrifice far longer than most of us have suspected, if one widens the current narrow definition of human sacrifice to include events where a life is taken in order to bring about a better future for the commonwealth, appease the gods, or ensure a Roman victory in battle.


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