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Gluon-gluon interactions in the bag model

An effective spin-dependent interaction Hamiltonian for low-lying gluon modes is calculated to O(±s) in the MIT bag model. We give expressions for the energy shifts of low-lying glueballs.

Meson, baryon, and glueball masses in the MIT bag model

We present a consistent and unified study of the spectrum of low-lying mesons, baryons, and glueballs using the MIT bag model, incorporating several improvements in the model. We correct for the center-of-mass motion, use a running coupling αs(R), include self-energy terms for quarks and gluons confined in a cavity, and get the bag constant from a model of the QCD vacuum. Our fit to the meson and

Loop diagrams in boxes

Methods for computing loop diagrams in confined scalar and gauge theories are developed. We construct propagators with different types of boundary conditions in boxes (rectangular cavities) using the method of image charges, which allows for a separation of the short-distance singularities. The techniques are illustrated by a calculation of the Casimir effect in a box using a covariant gauge, and

Concepts of industrial diafiltration systems

The use of diafiltration as part of ultrafiltration processes on an industrial scale is now the state-of-the-art in the food & beverage, biotech and pharma industry for the recovery of fermentation broth. In this paper the advantages and disadvantages of the most common process modes of diafiltration - batch and continuous - will be discussed. Further, the new concept of counter-current diafil

Kinetics of the gas‐phase reactions of chlorine atoms with CH²F², CH³CCl³, and CF³CFH² over the temperature range 253–553 K

Relative rate techniques were used to study the title reactions in 930–1200 mbar of N2 diluent. The reaction rate coefficients measured in the present work are summarized by the expressions k(Cl + CH2F2) = 1.19 × 10−17 T2 exp(−1023/T) cm3 molecule−1 s−1 (253–553 K), k(Cl + CH3CCl3) = 2.41 × 10−12 exp(−1630/T) cm3 molecule−1 s−1 (253–313 K), and k(Cl + CF3CFH2) = 1.27 × 10−12 exp(−2019/T) cm3 molec

Effects of target pre-heating and expansion on terahertz radiation production from intense laser-solid interactions

The first experimental measurements of intense laser-driven terahertz (THz) radiation from a solid target which is preheated by an intense pulse of laser-accelerated protons is reported. The total energy of the THz radiation is found to decrease by approximately a factor of 2 compared to a cold target reference. This is attributed to an increase in the scale length of the preformed plasma, driven

wing blister, A new Drosophila laminin alpha chain required for cell adhesion and migration during embryonic and imaginal development

We report the molecular and functional characterization of a new α chain of laminin in Drosophila. The new laminin chain appears to be the Drosophila counterpart of both vertebrate α2 (also called merosin) and α1 chains, with a slightly higher degree of homology to α2, suggesting that this chain is an ancestral version of both αl and α2 chains. During embryogenesis, the protein is associated with

Discovery of Teneurins

Teneurins were first discovered and published in 1993 and 1994, in Drosophila melanogaster as Ten-a and Ten-m. They were initially described as cell surface proteins, and as pair-rule genes. Later, they proved to be type II transmembrane proteins, and not to be pair-rule genes. Ten-m might nonetheless have had an ancestral function in clock-based segmentation as a Ten-m oscillator. The turn of the

Epithelial synthesis of tenascin at tips of growing bronchi and graded accumulation in basement membrane and mesenchyme

The extracellular matrix protein, tenascin, has been proposed as mediator in epithelial-mesenchymal interactions because of its characteristic distribution during embryogenesis. Here we compared the accumulation of tenascin and laminin in the early chicken lung bud. Laminin is deposited in the basement membrane, starting at the tips and increasing along the shafts of growing primary and secondary

Finite Element Modeling for vibration transmission in a Cross Laminated Timber structure

This paper deals with a certain type of C.L.T. (Cross Laminated Timber) construction, in a residential building in Fristad, Sweden. The objective is to study impact noise transmission, at the lower frequency range (10-200 Hz), where wooden dwellings perform inefficiently, in terms of acoustic quality. The vibrational behavior of lightweight structures and specifically a multilayered floor separati

Starburst triggered by compressive tides in galaxy mergers

The tidal field of galaxies is known generally to be disruptive. However, in the case of galaxy mergers, a compressive mode of tidal wave may develop and last long enough to cocoon the formation of star clusters. Using an N‐body simulation of the Antennae galaxies, we derive the positions of these compressive regions and the statistics of their duration. Excellent agreement between the spatial dis