100 research outputs found
Spiranthes vernalis Engelm. & A. Gray
https://thekeep.eiu.edu/herbarium_specimens_byname/21408/thumbnail.jp
Faculty accountability and faculty workload: A preliminary cost analysis of their relationship as revealed by PhD productivity
General concerns for faculty accountability are examined in the context of faculty workload and costs. Graduating a PhD student is used as the unit for analysis. The unit is compared to instructional productivity. The data came from a 10-year interval at a major graduate university. Six liberal arts departments with a 225-member faculty provide the PhD output and workload information. Work equivalents are determined from institutional and faculty self-reports. Graduating a PhD is found to be equivalent to one-third of a full workload. Implications are given for comparisons between programs within a university and between types of institutions in the larger system of higher education. Concerns also emerge for improved personnel practices with respect to faculty work assignments.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43583/1/11162_2004_Article_BF00991561.pd
Antibody Complementarity-Determining Regions (CDRs) Can Display Differential Antimicrobial, Antiviral and Antitumor Activities
Background: Complementarity-determining regions (CDRs) are immunoglobulin (Ig) hypervariable domains that determine specific antibody (Ab) binding. We have shown that synthetic CDR-related peptides and many decapeptides spanning the variable region of a recombinant yeast killer toxin-like antiidiotypic Ab are candidacidal in vitro. An alanine-substituted decapeptide from the variable region of this Ab displayed increased cytotoxicity in vitro and/or therapeutic effects in vivo against various bacteria, fungi, protozoa and viruses. the possibility that isolated CDRs, represented by short synthetic peptides, may display antimicrobial, antiviral and antitumor activities irrespective of Ab specificity for a given antigen is addressed here.Methodology/Principal Findings: CDR-based synthetic peptides of murine and human monoclonal Abs directed to: a) a protein epitope of Candida albicans cell wall stress mannoprotein; b) a synthetic peptide containing well-characterized B-cell and T-cell epitopes; c) a carbohydrate blood group A substance, showed differential inhibitory activities in vitro, ex vivo and/or in vivo against C. albicans, HIV-1 and B16F10-Nex2 melanoma cells, conceivably involving different mechanisms of action. Antitumor activities involved peptide-induced caspase-dependent apoptosis. Engineered peptides, obtained by alanine substitution of Ig CDR sequences, and used as surrogates of natural point mutations, showed further differential increased/unaltered/decreased antimicrobial, antiviral and/or antitumor activities. the inhibitory effects observed were largely independent of the specificity of the native Ab and involved chiefly germline encoded CDR1 and CDR2 of light and heavy chains.Conclusions/Significance: the high frequency of bioactive peptides based on CDRs suggests that Ig molecules are sources of an unlimited number of sequences potentially active against infectious agents and tumor cells. the easy production and low cost of small sized synthetic peptides representing Ig CDRs and the possibility of peptide engineering and chemical optimization associated to new delivery mechanisms are expected to give rise to a new generation of therapeutic agents.Department of Education, Universities and Research, Basque GovermentFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Istituto Superiore di Sanita, National Research Project on A.I.D.S.Cariparma Banking FoundationBrazilian National Research CouncilUniv Parma, Sez Microbiol, Dipartimento Patol, I-43100 Parma, ItalyUniv Basque Country, Fac Med Odontol, Dept Inmunol, Microbiol Parasitol, Bilbao, SpainUniv Basque Country, Dept Enfermeria I, Bilbao, SpainUniv Milan, Dipartimento Sci Cliniche L Sacco, Sez Malattie Infettive Immunopatol, Milan, ItalyUniv Studi Parma, Dipartimento Clin Med, Nefrol Sci Prev, Parma, ItalyUniversidade Federal de São Paulo, Departamento Microbiol, Imunol Parasitol, Unidade Oncol Expt, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biofis, São Paulo, BrazilUniversidade Federal de São Paulo, Departamento Microbiol, Imunol Parasitol, Unidade Oncol Expt, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Biofis, São Paulo, BrazilDepartment of Education, Universities and Research, Basque Goverment: IT-264-07FAPESP: 06/50634-2Istituto Superiore di Sanita, National Research Project on A.I.D.S.: 50G.30Istituto Superiore di Sanita, National Research Project on A.I.D.S.: 40D.14Cariparma Banking Foundation: 2004.0190Brazilian National Research Council: research fellowshipWeb of Scienc
Neutrino-driven wind simulations and nucleosynthesis of heavy elements
Neutrino-driven winds, which follow core-collapse supernova explosions,
present a fascinating nuclear astrophysics problem that requires understanding
advanced astrophysics simulations, the properties of matter and neutrino
interactions under extreme conditions, the structure and reactions of exotic
nuclei, and comparisons against forefront astronomical observations. The
neutrino-driven wind has attracted vast attention over the last 20 years as it
was suggested to be a candidate for the astrophysics site where half of the
heavy elements are produced via the r-process. In this review, we summarize our
present understanding of neutrino-driven winds from the dynamical and
nucleosynthesis perspectives. Rapid progress has been made during recent years
in understanding the wind with improved simulations and better micro physics.
The current status of the fields is that hydrodynamical simulations do not
reach the extreme conditions necessary for the r-process and the proton or
neutron richness of the wind remains to be investigated in more detail.
However, nucleosynthesis studies and observations point already to
neutrino-driven winds to explain the origin of lighter heavy elements, such as
Sr, Y, Zr.Comment: Submitted to: J. Phys. G: Nucl. Phy
Serum Stabilities of Short Tryptophan- and Arginine-Rich Antimicrobial Peptide Analogs
Several short antimicrobial peptides that are rich in tryptophan and arginine residues were designed with a series of simple modifications such as end capping and cyclization. The two sets of hexapeptides are based on the Trp- and Arg-rich primary sequences from the "antimicrobial centre" of bovine lactoferricin as well as an antimicrobial sequence obtained through the screening of a hexapeptide combinatorial library.HPLC, mass spectrometry and antimicrobial assays were carried out to explore the consequences of the modifications on the serum stability and microbicidal activity of the peptides. The results show that C-terminal amidation increases the antimicrobial activity but that it makes little difference to its proteolytic degradation in human serum. On the other hand, N-terminal acetylation decreases the peptide activities but significantly increases their protease resistance. Peptide cyclization of the hexameric peptides was found to be highly effective for both serum stability and antimicrobial activity. However the two cyclization strategies employed have different effects, with disulfide cyclization resulting in more active peptides while backbone cyclization results in more proteolytically stable peptides. However, the benefit of backbone cyclization did not extend to longer 11-mer peptides derived from the same region of lactoferricin. Mass spectrometry data support the serum stability assay results and allowed us to determine preferred proteolysis sites in the peptides. Furthermore, isothermal titration calorimetry experiments showed that the peptides all had weak interactions with albumin, the most abundant protein in human serum.Taken together, the results provide insight into the behavior of the peptides in human serum and will therefore aid in advancing antimicrobial peptide design towards systemic applications
AWAKE, the advanced proton driven plasma wakefield acceleration experiment at CERN
The Advanced Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE) aims at studying plasma wakefield generation and electron acceleration driven by proton bunches. It is a proof-of-principle R&D experiment at CERN and the world׳s first proton driven plasma wakefield acceleration experiment. The AWAKE experiment will be installed in the former CNGS facility and uses the 400 GeV/c proton beam bunches from the SPS. The first experiments will focus on the self-modulation instability of the long (rms ~12 cm) proton bunch in the plasma. These experiments are planned for the end of 2016. Later, in 2017/2018, low energy (~15 MeV) electrons will be externally injected into the sample wakefields and be accelerated beyond 1 GeV. The main goals of the experiment will be summarized. A summary of the AWAKE design and construction status will be presented
Women and power: a theoretical approach using the example of copreneurial businesses
Despite the gradual recognition of strategic issues related to the integration of women into the economy, female entrepreneurship continues to receive little attention. Family business research attributes this situation to a lack of recognition given to the (decisive) role of women in these organizations. However, there is one type of family governance that formally acknowledges the man/woman combination: the copreneurial company. Copreneurs are couples who run a business together. This theoretical article highlights the role of women in the copreneurial context by distinguishing between formal and informal power- the latter being primarily held by women, but which is no less influential. The distribution of power reduces opposition costs between partners and the social costs of non-compliance, and improves the clarity of the entrepreneurial structure. Moreover, it increases satisfaction and a feeling of equality between the partners. These results can be generalized and shed light on the role of women in other entrepreneurial and social contexts. This article is published as part as part of a collection on the role of women in management and business
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