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Robert Conte has worked in virtually every aspect of the comic-book industry including retail, distribution, writing, editing, and book packaging. 'I've been blessed to have accomplished many things in the [...]

We provide closed form solutions for an equation which describes the transport of turbulent kinetic energy in the framework of a turbulence model with a single equation.

We provide a Lax pair for the surfaces of Voss and Guichard, and we show that such particular surfaces considered by Gambier are characterized by a third Painlevé function.

We perform the analytic study of the buoyancy-drag equation with a time-dependent acceleration γ(t) by two methods. We first determine its equivalence class under the point transformations of Roger Liouville, and thus for some values of γ(t) define a time-dependent Hamiltonian from which the buoyancy-drag equation can be derived. We then determine the Lie point symmetries of the buoyancy-drag equation, which only exist for values of γ(t) including the previous ones, plus additional classes of accelerations for which the equation is reducible to an Abel equation. This allows us to exhibit two régimes for the asymptotic (large time t) solution of the buoyancy-drag equation. It is shown that they describe a mixing zone driven by the Rayleigh–Taylor instability and the Richtmyer–Meshkov instability, respectively.

In order to describe the coupling between the Kerr nonlinearity and the stimulated Brillouin scattering, Mauger et al. recently proposed a system of partial differential equations in three complex amplitudes. We perform here its analytic study by two methods. The first method is to investigate the structure of singularities, in order to possibly find closed form single-valued solutions obeying this structure. The second method is to look at the infinitesimal symmetries of the system in order to build reductions to a lesser number of independent variables. Our overall conclusion is that the structure of singularities is too intricate to obtain closed form solutions by the usual methods. One of our results is the proof of the nonexistence of traveling waves. [ABSTRACT FROM AUTHOR]

A system of two discrete nonlinear Schrödinger equations of the Ablowitz-Ladik type with a saturable nonlinearity is shown to admit a doubly periodic wave, whose long wave limit is also derived. As a by-product, several new solutions of the elliptic type are provided for NLS-type discrete and continuous systems.

AbstractWe consider the anharmonic oscillator with an arbitrary-degree anharmonicity, a damping term and a forcing term, all coefficients being time-dependent:Its physical applications range from the atomic Thomas-Fermi model to Emden gas dynamics equilibria, the Duffing oscillator and numerous dynamical systems. The present work is an overview which includes and generalizes all previously known results of partial integrability of this oscillator. We give the most general two conditions on the coefficients under which a first integral of a particular type exists. A natural interpretation is given for the two conditions. We compare these two conditions with those provided by the Painlevé analysis.

AbstractWe consider the cubic and quartic Hénon-Heiles Hamiltonians with additional inverse square terms, which pass the Painlevé test for only seven sets of coefficients. For all the not yet integrated cases we prove the singlevaluedness of the general solution. The seven Hamiltonians enjoy two properties: meromorphy of the general solution, which is hyperelliptic with genus two and completeness in the Painlevé sense (impossibility to add any term to the Hamiltonian without destroying the Painlevé property).

AbstractAmong the recently found discretizations of the sixth Painlevé equation P6, only the one of Jimbo and Sakai admits a discrete Lax pair, which does establish its integrability. However, a subtle restriction in this Lax pair prevents the possibility to generalize it in order to find the other missing Lax pairs. It happens that the same restriction already exists in the matrix Lax pair of Jimbo and Miwa for the continuous P6. In this preliminary article, we remove this last restriction and give a matrix Lax pair for P6 which is traceless, rational in the dependent and independent variables, holomorphic in the monodromy exponents, with four Fuchsian singularities in the complex plane of the spectral parameter. Its only minor drawback is the presence of the apparent singularity which always exists in the scalar Lax pair.

A birational transformation is one which leaves invariant an ordinary differential equation, only changing its parameters. We first recall the consistent truncation which has allowed us to obtain the first degree birational transformation of Okamoto for the master Painlevé equation P6. Then we improve it by adding a preliminary step, which is to find all the Riccati subequations of the considered Pn before performing the truncation. We discuss in some detail the main novelties of our method, taking as an example the simplest Painlevé equation for that purpose, P2. Finally, we apply the method to P5 and obtain its two inequivalent first degree birational transformations.

Since its elaboration in 1983 by Weiss, Tabor and Carnevale, the method to explicitly build the Bäcklund transformation of a partial differential equation (PDE) from singularity analysis only has been improved in several complementary directions, and at the present time it succeeds for practically all PDEs in 1+1 -dimensions. The current state of the art is presented, and the emphasis is put on understanding the method. There are two important stages: first, the definition (identified with a Darboux transformation) of a resummation variable to make the Laurent series a finite one as requested by the definition of the word integrability; second, the link (identified with a linearizing formula to be taken from the classification of Painlevé and Gambier) between this resummation variable and the Lax pair to be found.

Relative phylogenetic divergence of the members of the Pongidae family has been based on genetic evidence. The recent isolation of subtelomeric probes specific for human (HSA) chromosomes 1q, 11p, 13q, and 16q has prompted us to cross hybridize these to the chromosomes of the chimpanzee (Pan troglodytes, PTR), gorilla (Gorilla gorilla, GGO), and orangutan (Pongo pygmaeus, PPY) to search for their equivalent locations in the great apes. Hybridization signals to the 1q subtelomeric DNA sequence probe were observed at the termini of human (HSA) 1q, PTR 1q, GGO 1q, PPY 1q, while the fluorescent signals to the 11p subtelomeric DNA sequence probe were observed at the termini of HSA 11p, PTR 9p, GGO 9p, and PPY 8p. Fluorescent signals to the 13q subtelomeric DNA sequence probe were observed at the termini of HSA 13q, PTR 14q, GGO 14q, and PPY 14q, and positive signals to the 16p subtelomeric DNA sequence probe were observed at the termini of HSA 16q, PTR 18q, GGO 17q, and PPY 19q. These findings apparently suggest sequence homology of these DNA families in the ape chromosomes. Obviously, analogous subtelomeric sequences exist in apes' chromosomes that apparently have been conserved through the course of differentiation of the hominoid species.

Chromosomal mosaicism during prenatal diagnosis has been a major concern. Nondisjunctional events can lead to mosaicism in a number of ways, including failure of chromosomal pairing, failure to separate, anaphase lag and abnormal segregation. We provide a concise review on various types of mosaicism with their clinical significance.

SummaryOne of the most frequent translocations involving the long arm of chromosome Y with autosomes is with the short arm of chromosome 15. The regions which are involved in this translocation fluoresce brightly, are highly heteromorphic and thus escape detection. Therefore, these abnormalities could not be fully characterized, especially in cases where parents are not available or paternity is disputed. Results from the employment of the selective staining techniques DA/DAPI and Q-banding have been inconclusive. FISH-technique using whole chromosome painting (WCP) probes should be used to decipher such translocations. We present a case where, even after using a battery of probes, the origin of extra material on chromosome 15p could not be identified though it was not a part of Yq.

Abstract: Pericentric inversions involving the secondary constriction (qh) region of chromosome 9 are considered to be normal variants. The evolutionary mechanisms and conservation of these inversions via Mendelian fashion have been investigated since the advent of banding techniques. Routine cytogenetic techniques cannot provide the fine characterization necessary to determine the type of genetic material involved in these rearrangements. Therefore, the fluorescence in situ hybridization technique with the human centromere-specific alpha satellite and the beta satellite (D9Z5) and classical satellite (D9Z1) human DNA probes were used to identify the breakpoints of chromosome 9 pericentric inversions. Four unique types of pericentric inversions involving the 9qh region were observed, and the mechanism may be due to breakage and reunion at the proposed breakpoints. They are: type A inversions consist of breakpoints within the alpha and beta satellite DNA regions; type B consist of breakpoints within the beta satellite DNA region and band 9q13; type C involve breakage within the beta and classical satellite DNA regions, and type D have breakpoints within the alpha and classical satellite DNA regions. Obviously, reshuffling of satellite DNA sequences has occurred, which has given rise to a variety of heteromorphisms whose clinical significance remains obscure.

Prostate cancer is the most frequent malignancy and the second leading cause of cancer deaths among males in the Western world. The clinical course of the disease is highly complex, and genetic factors underlying tumorigenesis are poorly understood. The challenge that lies ahead is to identify the important gene(s) that causes adenocarcinoma of the prostate. Chromosomal findings by cytogenetic and molecular methods, including Southern blotting, microsatellite analysis, fluorescence in situ hybridization, and comparative genomic hybridization, revealed a high frequency of chromosomal aberrations of heterogeneous nature, including: — 1, + I, —1q, +4, -6q, -7, + 7, -8, -8p, -8q, +i(8q), -9, -9p, -10, + 10, +11, -12, -13q, -16, -16q, +16, -17, +17, +17q, -18, +18, -18, +19p, +20q, +X, -Xq, — Y, and +Y. Specific chromosomal regions of alterations were 1q24-25, 2cen-q31, 5cemq23.3, 6q14-23.2, 7q22-q31, 8p12-21, 8p22, 8q24-qter, 10q22.1, 10q23-25, 11p11.2, 16q24, 17p13.1, 18q12.2, and Xq11-12. Recently, a predisposing gene for early onset has been localized on 1q42.2-43. The losses of heterozygosity at specific chromosomal loci from chromosomes 5q, 6q, 7q, 8p, 8q, 10q, 13q, 16q, 17p, 17q, and 18q are generally correlated with poor prognosis in advanced tumor stage. In addition, an abnormal function of known tumor suppressor genes from these regions have been observed in prostate cancer. Although, the amplification of the androgen receptor gene at Xq11-13 and HER-2/neu gene at 17q11.2-q12 are novel findings, no single gene has been implicated in harboring prostate cancer.Frequent inactivation of PTEN/MMACl tumor suppressor gene at 10q23, MXI-1 at 10q25, KAI-1 at 11p11.2, Rb at 13q14.2, and p53 at 17p13.1 and deregulation of c-myc oncogene at 8q24 have recently been the subject of intense scrutiny and debate.

Trisomy 4p syndrome is a distinct clinical entity which was noted almost a quarter century ago by Wilson et al. [71] and later was delineated by Gonzalez and colleagues [29]. The variation in the length of duplicated segment usually associated with monosomy of other genetic material which has resulted in confusion and as a result a socalled 4p syndrome could not be recognized without cytogenetic analysis. We wish to draw the attention of clinicians to this subject by presenting the description of over 75 cases including one from our clinic and stress the point that molecular approaches are imperative to characterize this anomaly. After extensive review, it appears that patients retaining at least the distal two-thirds to the entire short arm share an overlapping phenotypic expression that constitutes pure trisomy 4p syndrome which includes prominent glabella, bulbous nose with flat or depressed nasal bridge, retrognathia, pointed chin, short neck with low hairline, enlarged ears with abnormal helix and antihelix, rocker-bottom feet with prominent heel, Arachnodactyly and camptodactyly. Molecular characterization of 4p is imperative. We have also included an extensive bibliography for clinicians who may find it useful as a single reference source for evaluating their future cases.

The profession has long recognized that among the various lesions which may produce a peritonitis in the course of typhoid fever, rupture of the mesenteric glands is one, and yet in the many text-books which have been consulted there is not a reference given to a specific reported case. Nothnagel's "System" and Osier's "Practice," for example, fail to give a single instance of a mesenteric gland producing peritonitis; but each mentions it as a possible cause of such a complication in enteric fever. Keen1 records references under this heading, but all of them prove to be cases of obscure peritonitis of unknown origin, where the reporter has only suggested the possibility of a ruptured mesenteric gland being the cause. It would, therefore, seem that such an occurrence is very uncommon, and a search through the recent literature on the subject tends to confirm this view, for I can find but

The search for the perfect germicide began when Lister first applied the principles of Pasteur to the practice of surgery. The perfect germicide should meet two simple requirements: It must kill all parasitic life, while causing no harm to any cell of the living body.The problem has been partially solved for certain groups of infective agents, all of which, however, belong to the lower forms of animal life. The infective agents more closely related to the plant kingdom, the bacteria, have shown a greater resistance to lethal agents than is possessed by the cells of the animal body, and therefore the great problem of surgery, the prevention and control of bacterial infection, remains only partially solved.The lethal effect of all the usual germicides on the animal cells, with the clinical result of retardation and inhibition of the natural processes of repair, have become so well recognized of late

We report on a new chromosomal finding in a newborn male with hypertelorism, apparently low-set malformed ears with patent canal, micrognathia with narrow high-arched palate, bilateral webbing of neck with low posterior hairline, widely spaced nipples, and complex heart anomalies. Initially, what appeared to be a simple paracentric inversion of the long arm of chromosome 9, that is, 46,XY, inv(9)(q31q34) by routine GTG-banding technique was later determined to be a paracentric inversion with deletion of the band 9q34.1 by FISH technique using an abl unique sequence DNA probe. Thus the cytogenetic diagnosis was modified to 46,XY,der(9) inv(9)(q31q34.1)del(q34.1). Nevertheless, the presence of telomeric repeat sequences in the inverted chromosome 9 suggests that either healing has occurred by adding [TTAGGG]n sequences to the nontelomeric end (q31) by the enzyme telomerase or telomeric sequences were not affected during this inversion process. This abnormality is a rare occurrence and has never been reported before either because of a high rate of lethality or it has been undetected by routine cytogenetic techniques. The other abnormal cases with apparent paracentric inversions could also have a complex nature with congenital anomalies associated with loss of “few” DNA sequences as exemplified here. Am. J. Med. Genet. 68:409–411, 1997. © 1997 Wiley-Liss, Inc.

The Wolf-Hirschhorn syndrome (WHS) is caused by a partial deletion in the short arm of chromosome 4 band 16.3 (4p16.3). A unique-sequence human DNA probe (39 kb) localized within this region has been used to search for sequence homology in the apes' equivalent chromosome 3 by FISH-technique. The WHS loci are conserved in higher primates at the expected position. Nevertheless, a control probe, which detects alphoid sequences of the pericentromeric region of humans, is diverged in chimpanzee, gorilla, and orangutan. The conservation of WHS loci and divergence of DNA alphoid sequences have further added to the controversy concerning human descent.

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