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Owing to their specific property profile, titanium materials are particularly used in aerospace and medical technology applications. Highly β-stabilized titanium alloys are becoming more and more important for they can be strengthened by martensite decomposition and/or precipitation hardening, thus allowing the property profile to be adapted to the respective application. Not only α and β phase can occur in the respective alloys, but also the α’, α” or ω phase. The sample preparation is particularly problematic when high fractions of α” and β phase are present. They are characterized by a very low stiffness and strength, thus tending to form smear and deformation layers. Three examples will be quoted to describe the sample preparation of titanium materials with a high proportion of β-stabilizers (niobium, molybdenum, and tantalum) and various micrographs will be shown.

Nephropathic cystinosis is an autosomal recessive disorder caused by the defective transport of cystine out of lysosomes. Recently, the causative gene (CTNS) was identified and presumed to encode an integral membrane protein called cystinosin. Many of the disease-associated mutations in CTNS are deletions, including one >55 kb in size that represents the most common cystinosis allele encountered to date. In an effort to determine the precise genomic organization of CTNS and to gain sequence-based insight about the DNA within and flanking cystinosis-associated deletions, we mapped and sequenced the region of human chromosome 17p13 encompassing CTNS. Specifically, a bacterial artificial chromosome (BAC)-based physical map spanning CTNS was constructed by sequence-tagged site (STS)-content mapping. The resulting BAC contig provided the relative order of 43 STSs. Two overlapping BACs, which together contain all of the CTNS exons as well as extensive amounts of flanking DNA, were selected and subjected to shotgun sequencing. A total of 200,237 bp of contiguous, high-accuracy sequence was generated. Analysis of the resulting data revealed a number of interesting features about this genomic region, including the long-range organization of CTNS, insight about the breakpoints and intervening DNA associated with the common cystinosis-causing deletion, and structural information about five genes neighboring CTNS (human ortholog of rat vanilloid receptor subtype 1 gene, CARKL, TIP-1, P2X5, and HUMINAE). In particular, sequence analysis detected the presence of a novel gene (CARKL) residing within the most common cystinosis-causing deletion. This gene encodes a previously unknown protein that is predicted to function as a carbohydrate kinase. Interestingly, both CTNS and CARKL are absent in nearly half of all cystinosis patients (i.e., those homozygous for the common deletion). [The sequence data described in this paper have been submitted to the GenBank data library under accession nos. AF168787 and AF163573.]

Helianthus petiolaris andH. niveus are polytypic species which are morphologically distinct at the periphery of their ranges but intergrade in areas of sympatry.Helianthus niveus includes both annual and perennial members, whereasH. petiolaris is strictly annual. Chloroplast DNA and nuclear ribosomal DNA restriction site data were used to reconstruct the evolutionary history of populations of the two species. Cladistic analyses reveal the following: (1) neither species is monophyletic; (2) the annual habit is derived once in this complex; and (3) the region of morphological intergradation appears to be primary in origin. The significance of interbreeding versus common descent in defining species concepts is discussed in relation to the above cladistic analyses.

Abstract: The drug combination N-(phosphonacetyl)-l-aspartic acid (PALA), methylmercaptopurine riboside (MMPR) and 6-aminonicotinamide (6AN), referred to as PMA, induces regressions of advanced CD8F1 murine mammary carcinomas in vivo. We demonstrated that CD8F1 tumor regressions were preceded by the appearance of apoptotic bodies, as observed by microscopic examination of morphology and TUNEL end-labeling, and fragmentation of DNA into nucleosomal “ladder” patterns. These indications of apoptosis were present as early as 6 h after simultaneous administration of MMPR and 6AN and further increased by over fivefold during the next 3 to 6 h, then remained at 7 to 12.8% (0.6 to 2.4% in saline-treated controls) of the cell population for at least 24 h after MMPR + 6AN administration. The 5′-phosphate derivative of MMRP, MMPR-5P, which inhibits de novo purine biosynthesis, was present at a “steady-state” level, and significant (40%) depletion of ATP had occurred by 3 h and both of these events preceded the onset of apoptosis. In addition, MMPR-5P was retained in CD8F1 tumors at a high level over a prolonged period (>96 h) even as tumors were undergoing regression. The prolonged presence of MMPR-5P was important for optimal chemotherapeutic effect, since treatment with iodotubercidin (IodoT), an inhibitor of MMPR/adenosine kinase, 6 h after MMPR + 6AN administration prevented the prolonged accumulation of MMPR-5P and reversed the regression of CD8F1 tumors. In addition, compared to the PMA-treated group, there was a significant restoration of ATP levels after treatment with IodoT. In individual PMA-treated CD8F1 tumors the degree of ATP depletion was found to correlate with the degree of tumor shrinkage at 24 h, after tumors had sufficient time to respond to treatment. These results define the time-course of drug-induced apoptosis in CD8F1 tumors, show that ATP depletion occurs prior to apoptosis and demonstrate that prolonged retention of MMPR-5P is associated with optimal chemotherapy. Collectively, these results suggest that the depletion of ATP by PMA treatment may be a component of the biochemical apoptotic cascade in the CD8F1 tumor.

The method of dimensional reduction as applied to pure Yang-Mills theory by Manton and Harnadet al.can be related to the symplectic-reduction scheme developed by Marsden and Weinstein when applied to the phase space for a «classical» particle moving in the presence of a Yang-Mills field. If the data satisfy the appropriate conditions, one can use a technique similar to the collective motion to integrate the equations of motion of the particle. Il metodo della riduzione dimensionale come applicato alla pura teoria di Yang-Mills da Manton e Harnad può essere messo in relazione con lo schema di riduzione simplettica sviluppato da Marsden e Weinstein quando applicato allo spazio di fase per una particella ]laclassica» che si muove in presenza del campo di Yang-Mills, Se i dati soddisfano le condizioni appropriate, si può usare una tecnica simile al moto collettivo per integrare le equazioni di moto della particella. Метод размерного приведения, примененный Мантоном и Харнадом и др. к чистой теории Янга-Миллса, может быть связан с схемой симплектического приведения, развитой Марсденом и Вейнстейном применительно к фазовому пространству для «классической» частицы, движущейся в присутствии поля Янга-Миллса. Эсли данные удовлетворяют соответствующим условиям, то можно использовать технику, аналогичную коллективному движению, для интегрирования уравнений движения частицы.

Heiser [Heiser, C. B. (1951) Evolution 5, 42-51] hypothesized that Helianthus annuus ssp. texanus was derived by the introduction of H. annuus into Texas and subsequent introgression of genes from Helianthus debilis ssp. cucumerifolius into H. annuus. Although often considered to be one of the best cases of introgression in plants, alternative hypotheses to introgression, such as convergence or the joint retention of the ancestral condition, could not be ruled out in the original study. To test for the occurrence of introgression we examined 14 populations of H. annuus ssp. texanus, 14 allopatric populations of H. annuus, and three populations of H. debilis ssp. cucumerifolius with reference to diagnostic chloroplast DNA and nuclear ribosomal DNA markers. Thirteen of the 14 populations of H. annuus ssp. texanus had chloroplast DNA and/or ribosomal DNA markers of H. debilis ssp. cucumerifolius. In contrast, no chloroplast DNA or ribosomal DNA markers of H. debilis ssp. cucumerifolius were found in the 14 allopatric populations of H. annuus. Our findings provide strong support, therefore, for the hypothesized introgressive origin of H. annuus ssp. texanus.

THE TERM fetal ascites embraces a variety of conditions associated with watery accumulation in the fetal abdomen. Dorland,1 reviewing the world literature up to 1919, reported 320 cases. Since that time, an additional 18 cases2 of fetal ascites have been reported. In his excellent monograph, Dorland differentiated true fetal ascites, or an accumulation of serum in the fetal peritoneal cavity, from other conditions associated with watery accumulations in the fetal abdomen, namely, fetal urinary retention, generalized anasarca, congenital polycystic kidneys, cystic degenerations of the liver, and fluid distending the genital tract. The cause of true fetal ascites is obscure, but in many cases the condition is associated with malformations of the genital organs and imperforate anus. Fetal peritonitis is also a common finding and may result in ascites either through failure of the thickened peritoneum to reabsorb the normal peritoneal fluid or through an exudation from the inflamed

THE spectacular and bewilderingly rapid jump of the flea has always excited the curiosity and wonder of naturalists. In an attempt to explain the mechanism of the jump we have re-examined the morphology of Xenopsylla cheopis, particularly the exoskeleton and musculature, and have combined this detailed study with a series of high speed cine films.

The nature of selective penetrant permeability of synthetic polymer membranes is reviewed and discussed in terms of some of the factors that most affect the transport behavior. The interdependence of these factors is emphasized for diffusion and sorption in structurally heterogeneous membranes.A simple description of permeation behavior of asymmetric heterogeneous membranes can be employed when it is reasonable to assume that the major factors affecting penetrant transport are differences in solubilities due to a variation in polymer structure and composition through the membrane. The resultant equations have been applied to sets of hypothetical membranes of varying structures and solubility properties representative of real systems to predict rates of flow and the preference factor describing the different flow rates observed for permeation in opposite directions through an asymmetric membrane.

An electrochemical cell allowing the measurement of emf of formation cells for lead iodide was achieved. The emf of the cells with pure lead iodide was measured and formation thermodynamic functions of lead iodide in molten state have been computed. The emfs of cells with molten mixtures of PbI2+ KI were also measured, and excess thermodynamic functions of PbI2in the mixture have been computed. The excess free enthalpy GPbI2E. shows negative deviations from ideality whereas the excess entropy SPbl2Etakes positive values. This behaviour is explained by complex ion formation in the mixture.

Let G=KL and g=k+l be Lie group and Lie algebra decompositions. This identifies kowith l*. Any G-invariant function, f, on g*induces by restriction a function f|ko=l*. We prove a formula which says that the integral curve through α∈kois obtained as b(t)α, where a(t)=exp tξ with ξ=Lf(α),

In previous papers we proposed a theory of internal supersymmetry using the superalgebra su(n/1) to give rise to a unified structure that included quarks and leptons in 2n-5 generations. In the present paper we suggest that the notion of superconnections as introduced by Quillen provides a natural setting for the dynamics of an internally supersymmetric theory with the Higgs field occurring as the "zero-th order part" of the superconnection. The Higgs mechanism enters quadratically into the curvature of the superconnection and hence quartically into the Lagrangian. The supercovariant derivative gives a coupling of the Higgs field to the matter field similar to that put in "by hand" in the Lagrangian of the Weinberg-Salam theory.

The classical London equations for superconductors are written in differential form notation and recast in relativistic form, where they yield the Proca equation. In particular, the field itself acts as its own charge carrier.

The emf of the cell

Oral swab samples, serum and colostrum was taken from 15 mares and 14 of their foals, within 24 h of birth. The presence of antibody against Actinobacillusspp. isolated from the oral cavity was investigated using agar gel immunodiffusion. Antibodies against 48 out of the 77 Actinobacillusisolates from all horses in the study were present in the respective sera of 13 mares and 9 foals. In 11 mother-foal pairs, the antibody content of the foal serum was similar to that of the mare, and in 9 cases this was reflected in the antibody content of colostrum from the mare. The results indicate that an immune response to Actinobacillusspp. colonising the oral cavity is present in many adult horses and that this immune response can be transferred from mother to foal via colostrum.

Assembly pheromones are demonstrated in 2 species of soft ticks, Ornithodoros tholozani (Laboulbéne & Mégnin) and Argas brumpti Neumann. Interspecific response is observed between Argas persicus (Oken) and the following species: A. brumpti, O. tholozani, Ornithodoros savignyi (Audouin). Feeding increased pheromone production and decreased tick response to pheromone. The role of assembly pheromones in host location is considered.

Both male and female Argas persicus mated more than 10 times. Males irradiated at doses which induce 99% dominant lethals (12 KR) were fully competitive for the first 2–3 weeks after exposure, then became aspermic. Decreasing the irradiation dose to 3 KR increased fertility to about 30%, but aspermia occurred about the same time as in higher doses.

Laboratory tests of phenyl-and 2-thienyl-substituted phosphinates and phosphonates, analogs to dichlorvos, trichlorfon, and naled, against agricultural insects are reported. The insects were the Mediterranean fruit fly, Ceratitis capitata (Wiedemann); the African migratory locust, Locusta migratoria migratorioides (Reiche and Fairmaire); the thaumetopeinid caterpillar, Thaumetopoea wilkinsoni Tams; the oleander aphid, Aphis nerii Boyer; and a mite species, the two-spotted spider mite, Tetranychus telarius(L.) (= T. urticae (Koch)). In general the parent compounds were more effective than the analogs tested. Compounds containing straight chain alkoxy substituents were more active on topical application than compounds containing branched chain alkoxy groups. Trichlorfon and its analogs were more effective against the two-spotted spider mite than against the oleander aphid. Dichlorvos, naled, some of their analogs, and trichlorfon were effective within 1 to a few hours after treatment. The Mediterranean fruit fly was the insect most sensitive to all the compounds tested.