Characterization by cDNA cloning of the mRNA for seminalplasmin, the major basic protein of bull semen.

A cDNA library derived from poly(A)+RNA of bull seminal vesicle tissue was screened with synthetic DNA probes specific for seminalplasmin (SAP), the major basic protein of bull semen. From a number of positive clones, pBSV12, containing a 577-bp insert, was identified and sequenced. The derived amino acid sequence comprises the known amino acid sequence of SAP with an amino terminal representing a putative signal sequence; at the carboxyl terminus the sequence contains an additional lysine residue. Present experimental data do not distinguish between two potential SAP precursor molecules, each starting with a methionine residue and differing by 10 amino acid residues in the leader peptide. Comparative Northern analysis reveals a SAP-specific mRNA of 700 bp, which lacks RNA from bovine testis as well as from seminal vesicle tissue of a bull calf; hence, expression of the SAP gene appears to be under androgen and/or developmental control. Southern analysis indicates that one gene appears to specify SAP. SAP-like DNA sequences were detected in ovine and porcine genomic DNA

Robustness to Algorithmic Singularities and Sensitivity in Computational Kinematics

A robust approach to computational kinematics intended to cope with algorithmic singularities is introduced in this article. The approach is based on the reduction of the original system of equations to a subsystem of bivariate equations, as opposed to the multivariate polynomial reduction leading to the characteristic univariate polynomial. The effectiveness of the approach is illustrated for the exact function-generation synthesis of planar, spherical, and spatial four-bar linkages. Some numerical examples are provided for the case of the spherical four-bar function generator with six precision points to show the benefits of the proposed method with respect to methods reported in the literature.The first author acknowledges the support of Universidad Politecnica de Valencia, research project PAID-00-09. The second author acknowledges the support of McGill University by means of a James McGill Professorship.Gracia Calandin, LI.; Angeles, J. (2011). Robustness to Algorithmic Singularities and Sensitivity in Computational Kinematics. Proceedings of the Institution of Mechanical Engineers part C - Journal of Mechanical Engineering Science. 225(4):987-999. doi:10.1243/09544062JMES2464S9879992254Raghavan, M., & Roth, B. (1993). Inverse Kinematics of the General 6R Manipulator and Related Linkages. Journal of Mechanical Design, 115(3), 502-508. doi:10.1115/1.2919218Lee, H. Y., Woernle, C., & Hiller, M. (1991). A Complete Solution for the Inverse Kinematic Problem of the General 6R Robot Manipulator. Journal of Mechanical Design, 113(4), 481-486. doi:10.1115/1.2912808Innocenti, C., & Parenti-Castelli, V. (1993). Echelon form solution of direct kinematics for the general fully-parallel spherical wrist. Mechanism and Machine Theory, 28(4), 553-561. doi:10.1016/0094-114x(93)90035-tGosselin, C. M., Sefrioui, J., & Richard, M. J. (1994). On the Direct Kinematics of Spherical Three-Degree-of-Freedom Parallel Manipulators of General Architecture. Journal of Mechanical Design, 116(2), 594-598. doi:10.1115/1.2919419Alizade, R. I., & Kilit, Ö. (2005). Analytical synthesis of function generating spherical four-bar mechanism for the five precision points. Mechanism and Machine Theory, 40(7), 863-878. doi:10.1016/j.mechmachtheory.2004.12.010Cervantes-Sánchez, J. J., Gracia, L., Rico-Martínez, J. M., Medellín-Castillo, H. I., & González-Galván, E. J. (2009). A novel and efficient kinematic synthesis approach of the spherical 4R function generator for five and six precision points. Mechanism and Machine Theory, 44(11), 2020-2037. doi:10.1016/j.mechmachtheory.2009.05.006Angeles, J. (2007). Fundamentals of Robotic Mechanical Systems. Mechanical Engineering Series. doi:10.1007/978-0-387-34580-2Bai, S., Hansen, M. R., & Angeles, J. (2009). A robust forward-displacement analysis of spherical parallel robots. Mechanism and Machine Theory, 44(12), 2204-2216. doi:10.1016/j.mechmachtheory.2009.07.005Sommese, A. J., & Wampler, C. W. (2005). The Numerical Solution of Systems of Polynomials Arising in Engineering and Science. doi:10.1142/5763Forsythe, G. E. (1970). Pitfalls in Computation, or why a Math Book isn’t Enough. The American Mathematical Monthly, 77(9), 931. doi:10.2307/2318109Angeles, J., Hommel, G., & Kovács, P. (Eds.). (1993). Computational Kinematics. Solid Mechanics and Its Applications. doi:10.1007/978-94-015-8192-9Yang, A. T., & Freudenstein, F. (1964). Application of Dual-Number Quaternion Algebra to the Analysis of Spatial Mechanisms. Journal of Applied Mechanics, 31(2), 300-308. doi:10.1115/1.3629601Gupta, K. C., & Beloiu, A. S. (1998). Branch and circuit defect elimination in spherical four-bar linkages. Mechanism and Machine Theory, 33(5), 491-504. doi:10.1016/s0094-114x(97)00078-

Buildup and dephasing of Floquet-Bloch bands on subcycle time scales

Strong light fields have created spectacular opportunities to tailor novel functionalities of solids. Floquet-Bloch states can form under periodic driving of electrons and enable exotic quantum phases. On subcycle time scales, lightwaves can simultaneously drive intraband currents and interband transitions, which enable high-harmonic generation (HHG) and pave the way towards ultrafast electronics. Yet, the interplay of intra- and interband excitations as well as their relation with Floquet physics have been key open questions as dynamical aspects of Floquet states have remained elusive. Here we provide this pivotal link by pioneering the ultrafast buildup of Floquet-Bloch bands with time- and angle-resolved photoemission spectroscopy. We drive surface states on a topological insulator with mid-infrared fields - strong enough for HHG - and directly monitor the transient band structure with subcycle time resolution. Starting with strong intraband currents, we observe how Floquet sidebands emerge within a single optical cycle; intraband acceleration simultaneously proceeds in multiple sidebands until high-energy electrons scatter into bulk states and dissipation destroys the Floquet bands. Quantum nonequilibrium calculations explain the simultaneous occurrence of Floquet states with intra- and interband dynamics. Our joint experiment-theory study opens up a direct time-domain view of Floquet physics and explores the fundamental frontiers of ultrafast band-structure engineering.Comment: 45 pages, 4 figures, 10 extended data figure

The role of situations in situational judgment tests: Effects on construct saturation, predictive validity, and applicant perceptions

Recent theorizing and empirical evidence suggesting that Situational Judgment Tests (SDI's) are more context-independent than previously thought has sparked a debate about the role of situation descriptions in S.M. To contribute to this debate and add to our understanding of how SJTs work, this article conceptually embeds SJT performance in a situation construal model and examines the effects of situation descriptions on the construct saturation and predictive validity of SJT scores, as well as on applicant perceptions. Across two studies (N = 1,092 and 578) and different Sri's, personality and cognitive ability were equally important determinants of SJT performance regardless of whether situation descriptions were presented or omitted. The effects of removing situation descriptions on the criterion-related validity of SJT scores differed depending on the breadth of the criteria. For predicting global job performance criteria (in-role performance and organizational citizenship behavior), SJT validity was not significantly affected, whereas it decreased for predicting more specific criteria (interpersonal adaptability, efficacy for teamwork). Finally, the effects of omitting situation descriptions in SJTs on applicant perceptions were either negligible or small. Implications for SJT theory, research, and design are discussed

Ultra late onset group B streptococcal sepsis with acute renal failure in a child with urethral obstruction: a case report

<p>Abstract</p> <p>Introduction</p> <p>Group B streptococci are a well-known cause of early and late onset sepsis. In neonates and older children gram-negative bacteria are mostly found in urinary tract infections and urosepsis. In adults predisposing factors for group B streptococci urinary tract infection may include diabetes mellitus and chronic renal failure.</p> <p>Case presentation</p> <p>We present a rare case of a five-month-old Caucasian boy with ultra late onset urosepsis and acute renal failure caused by group B streptococci serotype V. Excretion urography showed a subvesical obstruction that consequently was surgically corrected after antibiotic treatment of the acute infection.</p> <p>Conclusions</p> <p>Group B streptococci serotype V, urogenitary tract malformations, previous hospitalization and medical interventions may be important risk factors for the development of ultra late onset Group B streptococci sepsis in non-neonates.</p

Fundamental Parameters of He-Weak and He-Strong Stars

We carried out low resolution spectroscopic observations in the wavelength range 3400-4700 A of 20 He-weak and 8 He-strong stars to determine their fundamental parameters by means of the Divan-Chalonge-Barbier (BCD) spectrophotometric system. For a few He-weak stars we also estimate the effective temperatures and the angular diameters by integrating absolute fluxes observed over a wide spectral range. Non-LTE model calculations are carried out to study the influence of the He/H abundance ratio on the emergent radiation of He-strong stars and on their Teff determination. We find that the effective temperatures, surface gravities and bolometric absolute magnitudes of He-weak stars estimated with the BCD system and the integrated flux method are in good agreement between each other, and they also agree with previous determinations based on several different methods. The mean discrepancy between the visual absolute magnitudes derived using the Hipparcos parallaxes and the BCD values is on average 0.3 mag for He-weak stars, while it is 0.5 mag for He-strong stars. For He-strong stars, we note that the BCD calibration, based on stars in the solar environment, leads to overestimated values of Teff. By means of model atmosphere calculations with enhanced He/H abundance ratios we show that larger He/H ratios produce smaller BD which naturally explains the Teff overestimation. We take advantage of these calculations to introduce a method to estimate the He/H abundance ratio in He-strong stars. The BD of HD 37479 suggests that the Teff of this star remains fairly constant as the star spectrum undergoes changes in the intensity of H and He absorption lines. Data for the He-strong star HD 66765 are reported for the first time.Comment: Accepted for publication in A&

Structure and biochemical composition of desmosomes and tonofilaments isolated from calf muzzle epidermis.

Complexes of plasma membrane segments with desmosomes and attached tonofilaments were separated from the stratum spinosum cells of calf muzzle by means of moderately alkaline buffers of low ionic strength and mechanical homogenization. These structures were further fractionated by the use of various treatments including sonication, sucrose gradient centrifugaton, and extraction with buffers containing high concentrations of salt, urea, citric acid, or detergents. Subfractions enriched in desmosome-tonofilament-complexes and tonofilament fragments were studied in detail. The desmosome structures such as the midline, the trilaminar membrane profile, and the desmosomal plaque appeared well preserved and were notably resistant to the various treatments employed. Fractions containing desmosome-tonofilament complexes were invariably dominated by the nonmembranous proteins of the tonofilaments which appeared as five major polypeptide bands (apparent molecular weights: 48,000; 51,000; 58,000; 60,000; 68,000) present in molar ratios of approx. 2:1:1:2:2. Four of these polypeptide bands showed electrophoretic mobilities similar to those of prekeratin polypeptides from bovine hoof. However, the largest polypeptide (68,000 mol wt) migrated significantly less in polyacrylamide gels than the largest component of the hoof prekeratin (~ 63,000 mol wt). In addition, a series of minor bands, including carbohydrate-containing proteins, were identified and concluded to represent constituents of the desmosomal membrane. The analysis of protein-bound carbohydrates (total 270 μg/mg phospholipid in desmosomeenriched desmosome-enriched showed the presence of relatively high amounts of glucosamine, mannose, galactose, and sialic acids. These data as well as the lipid composition (e.g. high ratio of cholesterol to phospholipids, relatively high contents of sphingomyelin and gangliosides, and fatty acid pattern) indicate that the desmosomal membrane is complex in protein and lipid composition and has a typical plasma membrane character. The similarity of the desmosome-associated tonofilaments to prekeratin filaments and other forms of intermediate-sized filaments is discussed.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Mitochondrial Data in Monocot Phylologenetics

Mitochondrial sequences are an important source of data in animal phylogenetics, equivalent in importance to plastid sequences in plants. However, in recent years plant systematists have begun exploring the mitochondrial genome as a source of phylogenetically useful characters. The plant mitochondrial genome is renowned for its variability in size, structure, and gene organization, but this need not be of concern for the application of sequence data in phylogenetics. However, the incorporation of reverse transcribed mitochondrial genes ( processed paralogs ) and the recurring transfer of genes from the mitochondrion to the nucleus are evolutionary events that must be taken into account. RNA editing of mitochondrial genes is sometimes considered a problem in phylogenetic reconstruction, but we regard it only as a mechanism that may increase variability at edited sites and change the codon position bias accordingly. Additionally, edited sites may prove a valuable tool in identifying processed paralogs. An overview of genes and sequences used in phylogenetic studies of angiosperms is presented. In the monocots, a large amount of mitochondrial sequence data is being collected together with sequence data from plastid and nuclear genes, thus offering an opportunity to compare data from different genomic compartments. The mitochondrial and plastid data are incongruent when organelle gene trees are reconstructed. Possible reasons for the observed incongruence involve sampling of paralogous sequences and highly divergent substitution rates, potentially leading to longbranch attraction. The above problems are addressed in Acorales, Alismatales, Poales, Liliaceae, the Anthericum clade (in Agavaceae), and in some achlorophyllous taxa