Measurement of the Charge-Averaged Elastic Lepton-Proton Scattering Cross Section by the OLYMPUS Experiment.

We report the first measurement of the average of the electron-proton and positron-proton elastic scattering cross sections. This lepton charge-averaged cross section is insensitive to the leading effects of hard two-photon exchange, giving more robust access to the proton's electromagnetic form factors. The cross section was extracted from data taken by the OLYMPUS experiment at DESY, in which alternating stored electron and positron beams were scattered from a windowless gaseous hydrogen target.

Challenges in the Forging of Steel-Aluminum Bearing Bushings.

The current study introduces a method for manufacturing steel-aluminum bearing bushings by compound forging. To study the process, cylindrical bimetal workpieces consisting of steel AISI 4820 (1.7147, 20MnCr5) in the internal diameter and aluminum 6082 (3.

Mechanical and Thermal Influences on Microstructural and Mechanical Properties during Process-Integrated Thermomechanically Controlled Forging of Tempering Steel AISI 4140.

Thermomechanical treatment (TMT) describes the effect of thermal and mechanical conditions on the microstructure of materials during processing and offers possible integration in the forging process. TMT materials exhibit a fine-grained microstructure, leading to excellent mechanical properties. In this study, a two-step TMT upsetting process with intermediate cooling is used to demonstrate possibilities for a process-integrated treatment and corresponding properties.

Donor-Site Morbidity after Fibula Transplantation in Head and Neck Tumor Patients: A Split-Leg Retrospective Study with Focus on Leg Stability and Quality of Life.

The free fibula flap has been one of the most important microvascular grafts for orofacial reconstruction for more than 30 years. The complication rates at the donor-site reported in literature are considered to be low, but the published data vary greatly in some cases. In particular, restrictions in the stability and balance of the involved leg and their effects on the quality of life have been described very inconsistently to date.

Study of Two-Photon Exchange via the Beam Transverse Single Spin Asymmetry in Electron-Proton Elastic Scattering at Forward Angles over a Wide Energy Range.

We report on a new measurement of the beam transverse single spin asymmetry in electron-proton elastic scattering, A_{⊥}^{ep}, at five beam energies from 315.1 to 1508.4 MeV and at a scattering angle of 30°<θ<40°.

New Measurements of the Beam Normal Spin Asymmetries at Large Backward Angles with Hydrogen and Deuterium Targets.

New measurements of the beam normal single spin asymmetry in the electron elastic and quasielastic scattering on the proton and deuteron, respectively, at large backward angles and at ⟨Q^{2}⟩=0.22  (GeV/c)^{2} and ⟨Q^{2}⟩=0.35  ( GeV/c)^{2} are reported.

Hard Two-Photon Contribution to Elastic Lepton-Proton Scattering Determined by the OLYMPUS Experiment.

The OLYMPUS Collaboration reports on a precision measurement of the positron-proton to electron-proton elastic cross section ratio, R_{2γ}, a direct measure of the contribution of hard two-photon exchange to the elastic cross section. In the OLYMPUS measurement, 2.01 GeV electron and positron beams were directed through a hydrogen gas target internal to the DORIS storage ring at DESY.

First determination of the weak charge of the proton.

The Q(weak) experiment has measured the parity-violating asymmetry in ep elastic scattering at Q(2)=0.025(GeV/c)(2), employing 145 μA of 89% longitudinally polarized electrons on a 34.4 cm long liquid hydrogen target at Jefferson Lab.

Clinical research and development of tuberculosis diagnostics: moving from silos to synergy.

The development, evaluation, and implementation of new and improved diagnostics have been identified as critical needs by human immunodeficiency virus (HIV) and tuberculosis researchers and clinicians alike. These needs exist in international and domestic settings and in adult and pediatric populations. Experts in tuberculosis and HIV care, researchers, healthcare providers, public health experts, and industry representatives, as well as representatives of pertinent US federal agencies (Centers for Disease Control and Prevention, Food and Drug Administration, National Institutes of Health, United States Agency for International Development) assembled at a workshop proposed by the Diagnostics Working Group of the Federal Tuberculosis Taskforce to review the state of tuberculosis diagnostics development in adult and pediatric populations.

Measurement of strange quark contributions to the vector form factors of the proton at Q2 = 0.22 (GeV / c)2.

A new measurement of the parity violating asymmetry in elastic electron scattering on hydrogen at backward angles and at a four momentum transfer of Q;{2} = 0.22 (Ge V / c);{2} is reported here. The measured asymmetry is A_{LR} = (-17.

A caveat in mouse genetic engineering: ectopic gene targeting in ES cells by bidirectional extension of the homology arms of a gene replacement vector carrying human PARP-1.

Here we report an approach to generate a knock-in mouse model using an 'ends-out' gene replacement vector to substitute the murine Parp-1 (mParp-1) coding sequence (32 kb) with its human orthologous sequence (46 kb). Unexpectedly, examination of mutant ES cell clones and mice revealed that site-specific homologous recombination was mimicked in three independently generated ES cell clones by bidirectional extension of the vector homology arms using the endogenous mParp-1-flanking sequences as templates. This was followed by adjacent integration of the targeting vector, thus leaving the endogenous mParp-1 locus functional.

Ageing and PARP.

Poly(ADP-ribosyl)ation, which is the posttranslational modification of proteins with poly(ADP-ribose), is catalysed by poly(ADP-ribose) polymerases. DNA-strand break induced catalytic activation of two PARP isoforms, namely PARP-1 and -2, are in involved in DNA base-excision repair and other repair pathways. A body of correlative data suggests a link between DNA-damage induced poly(ADP-ribosyl)ation and mammalian longevity.

Evidence for strange-quark contributions to the nucleon's form factors at Q2=0.108 (GeV/c)2.

We report on a measurement of the parity violating asymmetry in the elastic scattering of polarized electrons off unpolarized protons with the A4 apparatus at MAMI in Mainz at a four momentum transfer value of Q(2)=0.108 (GeV/c)(2) and at a forward electron scattering angle of 30 degrees p)=[-1.

Introduction to poly(ADP-ribose) metabolism.

Poly(ADP-ribosyl)ation is a posttranslational modification of proteins in eukaryotic cells catalysed by a family of NAD+ ADP-ribosyl transferases, the poly(ADP-ribose) polymerases (PARPs). PARP-encoding genes now constitute a superfamily of at least 18 members encoding proteins that share homology with the catalytic domain of the founding member, PARP-1. Poly(ADP-ribose) metabolism is of central importance in a wide variety of biological processes including maintenance of genomic stability, DNA repair, transcriptional regulation, centromere function, modulation of telomere length, regulation of proteasomal protein degradation, regulation of endosomal vesicle trafficking and apoptosis.

Measurement of the transverse beam spin asymmetry in elastic electron-proton scattering and the inelastic contribution to the imaginary part of the two-photon exchange amplitude.

We report on a measurement of the asymmetry in the scattering of transversely polarized electrons off unpolarized protons, A( perpendicular), at two Q2 values of 0.106 and 0.230 (GeV/c)(2) and a scattering angle of 30 degrees View Article and Find Full Text PDF

The emerging role of poly(ADP-ribose) polymerase-1 in longevity.

In the present paper, the involvement of the family of poly(ADP-ribose) polymerases (PARPs), and especially of PARP-1, in mammalian longevity is reviewed. PARPs catalyse poly(ADP-ribosyl)ation, a covalent post-translational protein modification in eukaryotic cells. PARP-1 and PARP-2 are activated by DNA strand breaks, play a role in DNA base-excision repair (BER) and are survival factors for cells exposed to low doses of ionising radiation or alkylating agents.

Measurement of strange-quark contributions to the nucleon's form factors at Q(2) = 0.230 (GeV/c)(2).

We report on a measurement of the parity-violating asymmetry in the scattering of longitudinally polarized electrons on unpolarized protons at a Q2 of 0.230 (GeV/c)(2) and a scattering angle of theta (e) = 30 degrees - 40 degrees. Using a large acceptance fast PbF2 calorimeter with a solid angle of delta omega = 0.

Poly(ADP-ribosyl)ation inhibitors: promising drug candidates for a wide variety of pathophysiologic conditions.

Poly(ADP-ribose) polymerases are involved in many aspects of regulation of cellular functions. Using NAD+ as a substrate, they catalyse the covalent transfer of ADP-ribose units onto several acceptor proteins to form a branched ADP-ribose polymer. The best characterised and first discovered member of this multiprotein family is PARP-1.

The membrane-bound DnaJ protein located at the cytosolic site of glyoxysomes specifically binds the cytosolic isoform 1 of Hsp70 but not other Hsp70 species.

DnaJ proteins are located in various compartments of the eukaryotic cell. As previously shown, peroxisomes and glyoxysomes possess a membrane-anchored form of DnaJ protein located on the cytosolic face. Hints as to how the membrane-bound co-chaperone interacts with cytosolic soluble chaperones were obtained by examining the affinity between the DnaJ protein and various potential partners of the Hsp70 family.