25,285 research outputs found
Protection of outbred mice against a vaginal challenge by a Chlamydia trachomatis serovar E recombinant major outer membrane protein vaccine is dependent on phosphate substitution in the adjuvant.
Chlamydia trachomatis is the most common bacterial sexually-transmitted pathogen for which there is no vaccine. We previously demonstrated that the degree of phosphate substitution in an aluminum hydroxide adjuvant in a TLR-4-based C. trachomatis serovar E (Ser E) recombinant major outer membrane protein (rMOMP) formulation had an impact on the induced antibody titers and IFN-Îł levels. Here, we have extended these observations using outbreed CD-1 mice immunized with C. trachomatis Ser E rMOMP formulations to evaluate the impact on bacterial challenge. The results confirmed that the rMOMP vaccine containing the adjuvant with the highest phosphate substitution induced the highest neutralizing antibody titers while the formulation with the lowest phosphate substitution induced the highest IFN-Îł production. The most robust protection was observed in mice vaccinated with the formulation containing the adjuvant with the lowest phosphate substitution, as shown by the number of mice with positive vaginal cultures, number of positive cultures and number of C. trachomatis inclusion forming units recovered. This is the first report showing that vaccination of an outbred strain of mice with rMOMP induces protection against a vaginal challenge with C. trachomatis
Career Barriers and Coping Efficacy with International Students in Counseling Psychology Programs
This study uses Lent, Brown, and Hackett’s (1994) Social Cognitive Career Theory (SCCT) as a framework for understanding the career barriers and coping efficacy experienced by master’s counseling psychology international students. Grounded in SCCT, we described coping efficacy as international students’ perceived capability to navigate career barriers. Using Braun and Clarke’s thematic analysis (2006), we explored the career barriers and coping efficacy of 12 master’s counseling psychology international students. The first focus area, “international journey with multiple barriers,” includes five themes: interpersonal stress; language barriers; financial pressures; advising concerns; and visa and immigration-related stress. The second focus area, “agents of change in the midst of barriers,” includes five themes: self-regulating; stepping into discomfort; cognitive reappraising; becoming a change agent; and social support seeking. Findings demonstrate participants’ coping efficacy and perceptions of themselves as agents of change. This study deepens our understanding of career development among master’s counseling psychology international students
Does the thermal spike affect low-energy ion-induced interfacial mixing?
Molecular dynamics simulations have been used to obtain the three-dimensional
distribution of interfacial mixing and cascade defects in Ti/Pt multilayer
system due to single 1 keV impacts at grazing angle of incidence. The
Ti/Pt system was chosen because of its relatively high heat of mixing in the
binary alloy and therefore a suitable candidate for testing the effect of heat
of mixing on ion-beam mixing. However, the calculated mixing profile is not
sensitive to the heat of mixing. Therefore the thermal spike model of mixing is
not fully supported under these irradiation conditions. Instead we found that
the majority of mixing occurs after the thermal spike during the relaxation
process. These conclusions are supported by liquid, vacancy as well as adatom
analysis. The interfacial mixing is in various aspects anomalous in this
system: the time evolution of mixing is leading to a phase delay for Ti mixing,
and Pt exhibits an unexpected double peaked mixing evolution. The reasons to
these effects are discussed.Comment: 7 pages, 12 figures, Nucl. Instr. Meth. B211, 524. (2003
Promoting transparency through information : A global review of school report cards
The report examines the development of school report cards (SRCs) in selected countries around the world, with a particular emphasis on developing countries. It is intended to assist policy-makers and programme implementers in making informed decisions about how to use SRCs. The report includes: a review of the existing literature, interviews with 22 individuals at various levels of government covering different areas of responsibility connected with implementing countries, a descriptive summary of 14 countries, a summary of structures that can help review efforts undertaken to date, a set of newly developed indicators that integrate issues of accountability and anti-corruption effectiveness in the interpretation of SRCs, selected summaries and suggestions for improvement. The document builds on a USAID Working Paper developed in 2006 for the EQUIP 2 Project (Cameron, Moses, and Gillies, 2006) and examines cases in which report cards have proven especially successful in helping to improve transparency and accountability in education systems. It presents interview and survey findings from 14 countries where SRCs have been implemented in recent years, and compares their design and implementation. It gauges the settings for SRCs through an accountability and transparency index based on the authors’ observations, and examines whether and how SRCs can be used as part of the toolkit in the fight against corruption in the education sector. Finally, it proposes an implementation framework to help improve the delivery of education services and reduce corrupt practices. Some key highlights are: School report cards can be powerful tools to engage communities and hold schools accountable for providing students with a high-quality education. If the process is inclusive and participatory, SRCs can serve as a unique channel allowing education stakeholders to make more informed decisions based on school-level data. Reporting in SRCs appears to be more comprehensive than before. More comprehensive models include measuring outputs – a key factor in accountability – and parent perception. Most countries that appear to be less successful in SRC implementation lack a good understanding of SRC standards and what consequences can be expected based on SRC results. Most SRCs are missing clear, effective accountability measures, as well as clear links to those capable of making changes. More systematic efforts to employ SRCs to identify corruption often focus on specific areas, such as corruption in finance, teacher behaviour, and information systems. The exact relationship between implementation of SRCs and a country’s perceived level of education corruption is unclear. A number of countries with higher levels of perceived corruption in education are among those using more sophisticated SRC approaches. Accountability is a key element in the fight against corruption, and is led, in part, by transparency. Three case study areas, namely Indonesia, Brazil, and the state of Virginia in the United States, employ a combination of transparency and measurable consequences, which increase the accountability of schools
Far Ultraviolet Observations of the Dwarf Nova VW Hyi in Quiescence
We present a 904-1183 A spectrum of the dwarf nova VW Hydri taken with the
Far Ultraviolet Spectroscopic Explorer during quiescence, eleven days after a
normal outburst, when the underlying white dwarf accreter is clearly exposed in
the far ultraviolet. However, model fitting show that a uniform temperature
white dwarf does not reproduce the overall spectrum, especially at the shortest
wavelengths. A better approximation to the spectrum is obtained with a model
consisting of a white dwarf and a rapidly rotating ``accretion belt''. The
white dwarf component accounts for 83% of the total flux, has a temperature of
23,000K, a v sin i = 400 km/s, and a low carbon abundance. The best-fit
accretion belt component accounts for 17% of the total flux, has a temperature
of about 48,000-50,000K, and a rotation rate Vrot sin i around 3,000-4,000
km/s. The requirement of two components in the modeling of the spectrum of VW
Hyi in quiescence helps to resolve some of the differences in interpretation of
ultraviolet spectra of VW Hyi in quiescence. However, the physical existence of
a second component (and its exact nature) in VW Hyi itself is still relatively
uncertain, given the lack of better models for spectra of the inner disk in a
quiescent dwarf nova.Comment: 6 figures, 10 printed page in the journal, to appear in APJ, 1 Sept.
2004 issue, vol. 61
Experimental identification of aminomethanol (NH2CH2OH)—the key intermediate in the Strecker Synthesis
The Strecker Synthesis of (a)chiral α-amino acids from simple organic compounds, such as ammonia (NH3), aldehydes (RCHO), and hydrogen cyanide (HCN) has been recognized as a viable route to amino acids on primordial earth. However, preparation and isolation of the simplest hemiaminal intermediate – the aminomethanol (NH2CH2OH)– formed in the Strecker Synthesis to even the simplest amino acid glycine (H2NCH2COOH) has been elusive. Here, we report the identification of aminomethanol prepared in low-temperature methylamine (CH3NH2) – oxygen (O2) ices upon exposure to energetic electrons. Isomer-selective photoionization time-of-flight mass spectrometry (PI-ReTOF-MS) facilitated the gas phase detection of aminomethanol during the temperature program desorption (TPD) phase of the reaction products. The preparation and observation of the key transient aminomethanol changes our perception of the synthetic pathways to amino acids and the unexpected kinetic stability in extreme environments
Virasoro Symmetry of Constrained KP Hierarchies
Additional non-isospectral symmetries are formulated for the constrained
Kadomtsev-Petviashvili (\cKP) integrable hierarchies. The problem of
compatibility of additional symmetries with the underlying constraints is
solved explicitly for the Virasoro part of the additional symmetry through
appropriate modification of the standard additional-symmetry flows for the
general (unconstrained) KP hierarchy. We also discuss the special case of \cKP
--truncated KP hierarchies, obtained as Darboux-B\"{a}cklund orbits of initial
purely differential Lax operators. The latter give rise to Toda-lattice-like
structures relevant for discrete (multi-)matrix models. Our construction
establishes the condition for commutativity of the additional-symmetry flows
with the discrete Darboux-B\"{a}cklund transformations of \cKP hierarchies
leading to a new derivation of the string-equation constraint in matrix models.Comment: LaTeX, 11 pg
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