Analytical and experimental methods for determining the properties of materials at very high rates of loading

In the following report, some of the properties of ALCOA 7075 T651 aluminum, when subjected to high rates of loading, are experimentally investigated by impacting two rods of the material longitudinally. One rod is accelerated to a uniform velocity with an air gun launcher. The stationary second rod is instrumented with strain gages on its lateral surface in order to determine the strain-time history following impact. A detailed description of the experimental equipment is included. Simple, one-dimensional theory is used to determine the dynamic, elastic modulus of the test material under the impact condition. Several observations regarding the behavior of the material under dynamic, plastic loading conditions are made. The importance of equipment frequency response is noted and a method is suggested for estimating the experimental error in strain measurement resulting from equipment frequency response limitations. Several other possibilities of experimental error are noted and suggestions for improvement of the experimental apparatus are given. A theoretical development for the case of the longitudinal impact of two viscoelastic rods is presented and the numerical results are summarized for the impact of two rods of a Maxwell material. Computer programs to facilitate the determination of air gun parameters and to evaluate the solutions for the viscoelastic case are included --Abstract, page ii

On The Longitudinal Impact Of Two, Thin, Viscoelastic Rods

A one-dimensional representation of the distribution of stress and strain resulting from the longitudinal impact of two elastic rods is developed. A form of the correspondence principle is then used to obtain series solutions for stress and strain distributions resulting from the longitudinal impact of two rods of a Maxwell material. Results of the viscoelastic solutions, obtained by use of nondimensional variables, are presented graphically. © 1970 by ASME

The Heavy Quark Form Factors at Two Loops

We compute the two-loop QCD corrections to the heavy quark form factors in case of the vector, axial-vector, scalar and pseudo-scalar currents up to second order in the dimensional parameter $\epsilon = (4-D)/2$. These terms are required in the renormalization of the higher order corrections to these form factors.Comment: 131 pages, 3 figure

Heavy quark form factors at two loops in perturbative QCD

We present the results for heavy quark form factors at two-loop order in perturbative QCD for different currents, namely vector, axial-vector, scalar and pseudo-scalar currents, up to second order in the dimensional regularization parameter. We outline the necessary computational details, ultraviolet renormalization and corresponding universal infrared structure.Comment: 13 pages Latex, Proceedings of XLI International Conference of Theoretical Physics "Matter to the Deepest", Podlesice, Poland, September 3-8, 2017 and RADCOR 2017, St.~Gilgen Austria, Sept 24-29, 201

New Results on Massive 3-Loop Wilson Coefficients in Deep-Inelastic Scattering

We present recent results on newly calculated 2- and 3-loop contributions to the heavy quark parts of the structure functions in deep-inelastic scattering due to charm and bottom.Comment: Contribution to the Proc. of Loops and Legs 2016, PoS, in prin

3-Loop Corrections to the Heavy Flavor Wilson Coefficients in Deep-Inelastic Scattering

A survey is given on the status of 3-loop heavy flavor corrections to deep-inelastic structure functions at large enough virtualities $Q^2$.Comment: 13 pages Latex, 8 Figures, Contribution to the Proceedings of EPS 2015 Wie

Iterative and Iterative-Noniterative Integral Solutions in 3-Loop Massive QCD Calculations

Various of the single scale quantities in massless and massive QCD up to 3-loop order can be expressed by iterative integrals over certain classes of alphabets, from the harmonic polylogarithms to root-valued alphabets. Examples are the anomalous dimensions to 3-loop order, the massless Wilson coefficients and also different massive operator matrix elements. Starting at 3-loop order, however, also other letters appear in the case of massive operator matrix elements, the so called iterative non-iterative integrals, which are related to solutions based on complete elliptic integrals or any other special function with an integral representation that is definite but not a Volterra-type integral. After outlining the formalism leading to iterative non-iterative integrals,we present examples for both of these cases with the 3-loop anomalous dimension $\gamma_{qg}^{(2)}$ and the structure of the principle solution in the iterative non-interative case of the 3-loop QCD corrections to the $\rho$-parameter.Comment: 13 pages LATEX, 2 Figure

Squark Flavor Implications from B --> K(*) l+ l-

Recent experimental and theoretical progress regarding B --> K(*) l+ l- decays led to improved bounds on the Wilson coefficients C_9 and C_10 of four-fermion operators of the |Delta B|=|Delta S|=1 effective Hamiltonian. We analyze the resulting implications on squark flavor violation in the MSSM and obtain new constraints on flavor-changing left-right mixing in the up-squark-sector. We find the dimensionless flavor mixing parameter (delta^u_23)_LR, depending on the flavor-diagonal MSSM masses and couplings, to be as low as \lesssim 0.1. This has implications for models based on radiative flavor violation and leads to BR(B_s --> mu+ mu-) \gtrsim 1 x 10^-9. Rare top decays t --> c gamma, t --> c g, t --> c Z have branching ratios predicted to be below \lesssim few times 10^-8, 10^-6 and 10^-7, respectively.Comment: v2: 21 pages, 5 figures; Eq (A.2) and chirality-flipping mass insertion results clarified, references added, conclusions unchange

Benchmarking atomic data for astrophysics: a first look at the soft X-ray lines

A collection of the best solar and laboratory spectra in the soft X-rays is used here to perform a preliminary benchmark in this wavelength region, by comparing observed vs. predicted wavelengths and calibrated solar irradiances. The benchmark focuses on the Fe IX - Fe XIV ions,for which we have recently calculated the relevant atomic data, however a few other ions have also been benchmarked. The iron ions are dominating the soft X-rays, however a large fraction of the strongest soft X-ray lines due to n=4 -> n=3 transitions were previously unidentified. The strongest transitions are all identified here, in particular the decays from the core-excited levels (3s 3p^l 4s, l=$ 5,4,3,2,1 for Fe X, Fe XI, Fe XII, Fe XIII, and Fe XIV respectively) which are the strongest soft X-ray transitions from these ions. Many new identifications are proposed, some only tentatively. Good agreement in terms of solar irradiances between the soft X-ray and EUV (n=3 -> n=3) transitions is found, confirming the reliability of the new large-scale calculations. Some of the new atomic data and identifications are particularly important for the Solar Dynamic Observatory (SDO) Atmospheric Imaging Assembly (AIA) 94 A band.Comment: Accepted for publication in A&A (under revision

Identifying and Characterizing a Novel Protein Kinase STK35L1 and Deciphering Its Orthologs and Close-Homologs in Vertebrates

The human kinome containing 478 eukaryotic protein kinases has over 100 uncharacterized kinases with unknown substrates and biological functions. The Ser/Thr kinase 35 (STK35, Clik1) is a member of the NKF 4 (New Kinase Family 4) in the kinome with unknown substrates and biological functions. Various high throughput studies indicate that STK35 could be involved in various human diseases such as colorectal cancer and malaria. In this study, we found that the previously published coding sequence of the STK35 gene is incomplete. The newly identified sequence of the STK35 gene codes for a protein of 534 amino acids with a N-terminal elongation of 133 amino acids. It has been designated as STK35L (STK35 long). Since it is the first of further homologous kinases we termed it as STK35L1. The STK35L1 protein (58 kDa on SDS-PAGE), but not STK35 (44 kDa), was found to be expressed in all human cells studied (endothelial cells, HeLa, and HEK cells) and was down-regulated after silencing with specific siRNA. EGFP-STK35L1 was localized in the nucleus and the nucleolus. By combining syntenic and gene structure pattern data and homology searches, two further STK35L1 homologs, STK35L2 (previously known as PDIK1L) and STK35L3, were found. All these protein kinase homologs were conserved throughout the vertebrates. The STK35L3 gene was specifically lost during placental mammalian evolution. Using comparative genomics, we have identified orthologous sets of these three protein kinases genes and their possible ancestor gene in two sea squirt genomes. We found the full-length coding sequence of the STK35 gene and termed it as STK35L1. We identified a new third STK35-like gene, STK35L3, in vertebrates and a possible ancestor gene in sea squirt genome. This study will provide a comprehensive platform to explore the role of STK35L kinases in cell functions and human diseases