1,800 research outputs found
Shotgun Mass Spectrometry Workflow Combining IEF and LC-MALDI-TOF/TOF
We present a high throughput shotgun mass spectrometry workflow using a bidimensional peptide fractionation procedure consisting of isoelectric focusing and RP-HPLC prior to mass spectrometric analysis, with the aim of optimizing peptide separation and protein identification. As part of the workflow we used the ‘Isotope-Coded Protein Labeling’ (ICPL) method for accurate relative quantitation of protein expression. Such workflow was successfully applied to a comparative proteome analysis of schizophrenia versus healthy control brain tissues and can be an alternative to proteome researches
Physical Foundations of Landauer's Principle
We review the physical foundations of Landauer's Principle, which relates the
loss of information from a computational process to an increase in
thermodynamic entropy. Despite the long history of the Principle, its
fundamental rationale and proper interpretation remain frequently
misunderstood. Contrary to some misinterpretations of the Principle, the mere
transfer of entropy between computational and non-computational subsystems can
occur in a thermodynamically reversible way without increasing total entropy.
However, Landauer's Principle is not about general entropy transfers; rather,
it more specifically concerns the ejection of (all or part of) some correlated
information from a controlled, digital form (e.g., a computed bit) to an
uncontrolled, non-computational form, i.e., as part of a thermal environment.
Any uncontrolled thermal system will, by definition, continually re-randomize
the physical information in its thermal state, from our perspective as
observers who cannot predict the exact dynamical evolution of the microstates
of such environments. Thus, any correlations involving information that is
ejected into and subsequently thermalized by the environment will be lost from
our perspective, resulting directly in an irreversible increase in total
entropy. Avoiding the ejection and thermalization of correlated computational
information motivates the reversible computing paradigm, although the
requirements for computations to be thermodynamically reversible are less
restrictive than frequently described, particularly in the case of stochastic
computational operations. There are interesting possibilities for the design of
computational processes that utilize stochastic, many-to-one computational
operations while nevertheless avoiding net entropy increase that remain to be
fully explored.Comment: 42 pages, 15 figures, extended postprint of a paper published in the
10th Conf. on Reversible Computation (RC18), Leicester, UK, Sep. 201
Women's attitude towards prenatal screening for red blood cell antibodies, other than RhD
Background: Since July 1998 all Dutch women (± 200,000/y) are screened for red cell antibodies, other than anti-RhesusD (RhD) in the first trimester of pregnancy, to facilitate timely treatment of pregnancies at risk for hemolytic disease of the fetus and newborn (HDFN). Evidence for benefits, consequences and costs of screening for non-RhD antibodies is still under discussion. The screening program was evaluated in a nation-wide study. As a part of this evaluation study we investigated, according to the sixth criterium of Wilson and Jüngner, the acceptance by pregnant women of the screening program for non-RhD antibodies. Methods: Controlled longitudinal survey, including a prenatal and a postnatal measurement by structured questionnaires. Main outcome measures: information satisfaction, anxiety during the screening process (a.o. STAI state inventory and specific questionnaire modules), overall attitude on the screening program. Univariate analysis was followed by standard multivariate analysis to identify significant predictors of the outcome measures. Participants: 233 pregnant women, distributed over five groups, according to the screening result. Results: Satisfaction about the provided information was moderate in all groups. All screen- positive groups desired more supportive information. Anxiety increased in screen- positives during the screening process, but decreased to basic levels postnatally. All groups showed a strongly positive balance between perceived utility and burden of the
The ϕ6 Cystovirus Protein P7 Becomes Accessible to Antibodies in the Transcribing Nucleocapsid: A Probe for Viral Structural Elements
Protein P7 is a component of the cystovirus viral polymerase complex. In the unpackaged procapsid, the protein is situated in close proximity to the viral directed RNA polymerase, P2. Cryo-electron microscopy difference maps from the species ϕ6 procapsid have demonstrated that P7 and P2 likely interact prior to viral RNA packaging. The location of P7 in the post-packaged nucleocapsid (NC) remains unknown. P7 may translocate closer to the five-fold axis of a filled procapsid but this has not been directly visualized. We propose that monoclonal antibodies (Mabs) can be selected that serve as probe- reagents for viral assembly and structure. A set of Mabs have been isolated that recognize and bind to the ϕ6 P7. The antibody set contains five unique Mabs, four of which recognize a linear epitope and one which recognizes a conformational epitope. The four unique Mabs that recognize a linear epitope display restricted utilization of Vκ and VH genes. The restricted genetic range among 4 of the 5 antibodies implies that the antibody repertoire is limited. The limitation could be the consequence of a paucity of exposed antigenic sites on the ϕ6 P7 surface. It is further demonstrated that within ϕ6 nucleocapsids that are primed for early-phase transcription, P7 is partially accessible to the Mabs, indicating that the nucleocapsid shell (protein P8) has undergone partial disassembly exposing the protein’s antigenic sites
Search for Charged Higgs Bosons in e+e- Collisions at \sqrt{s} = 189 GeV
A search for pair-produced charged Higgs bosons is performed with the L3
detector at LEP using data collected at a centre-of-mass energy of 188.6 GeV,
corresponding to an integrated luminosity of 176.4 pb^-1. Higgs decays into a
charm and a strange quark or into a tau lepton and its associated neutrino are
considered. The observed events are consistent with the expectations from
Standard Model background processes. A lower limit of 65.5 GeV on the charged
Higgs mass is derived at 95 % confidence level, independent of the decay
branching ratio Br(H^{+/-} -> tau nu)
Diffractive Dijet Production at sqrt(s)=630 and 1800 GeV at the Fermilab Tevatron
We report a measurement of the diffractive structure function of
the antiproton obtained from a study of dijet events produced in association
with a leading antiproton in collisions at GeV at the
Fermilab Tevatron. The ratio of at GeV to
obtained from a similar measurement at GeV is compared with
expectations from QCD factorization and with theoretical predictions. We also
report a measurement of the (-Pomeron) and ( of parton in
Pomeron) dependence of at GeV. In the region
, GeV and , is
found to be of the form , which obeys
- factorization.Comment: LaTeX, 9 pages, Submitted to Phys. Rev. Letter
- …