3,112 research outputs found
Expanding Our Reach: Cross-Institutional Collaborations and Teacher Preparation in Hispanic Serving Institutions
This paper addresses the role of cross-institutional collaborations among Hispanic Serving Institutions (HSI). Specifically, we focus on the Enseñamos en el Valle Central Initiativeâa five-year, Title V, Developing Hispanic Serving Institutions (DHSI) grant for recruiting and preparing bilingual, Latinx teachers with a strong sense of self and service to their communities. While California four-year state institutions have historically been at the helm of preparing bilingual Kindergarten through 12th grade (K-12) teachers, this has not been the case for community colleges, which continue to be the first entry point into higher education for many Latinx communities. We discuss how the process of a two-week summer institute among two- and four-year faculty at two community colleges and one university expands conventional notions of teacher preparation, and how these non-normative approaches can lend to stronger pathways into the profession. Moreover, we share how our faculty development approaches disrupt the status quo in teacher preparation and how non-tenured Faculty of Color navigate the politics of disruption and how these race-gendered experiences hold relevance for how we understand teacher preparation and expanding access to underrepresented Teachers of Color into the teaching profession
Characterization of quaternary ammonium compounds in Flourensia xerophytic communities and response to UV-B radiation
As part of ongoing studies aimed at characterizing molecular components involved in the ecophysiological adaptations of native xerophytic plants from central Argentina, we demonstrated the presence of compatible solutes in Flourensia campestris (FC) and Flourensia oolepis (FO), specifically glycine betaine (GB) through TLC, LC, 1H NMR and 13C-NMR. GB content (leaves: 38±7ÎŒmolg-1 DW; adult plants>seedlings), and distribution (capitula>vegetative leaves>reproductive leaves>shoots>roots) were similar to other quaternary ammonium compound (QAC) accumulators. Flourensia seedlings from both species protected from UV-B exposure - a major abiotic stress in these natural environments - showed a significant increase of GB in the leaves (p<0.01) and a significant decrease in the roots (p<0.05). In FC and FO xerophytic shrub-dominated communities QACs were detected for the first time in 41% of co-occurring species (N=39), 14 of 28 natives (50%) and 2 of 11 exotics (18%), being GB in natives only (57% of QAC accumulators). GB may be considered as a chemotaxonomical character for the genus Flourensia, since it was also detected in Flourensia hirta, Flourensia niederleinii, Flourensia riparia, Flourensia fiebrigii, Flourensia macroligulata and Flourensia heterolepis. Our controlled UV-B experiments, set up in the same natural environment where these species grow, clearly show that solar UV-B - and therefore oxidative stress - is involved in regulating GB contents and within-plant distribution in FC and FO seedlings. The findings in Flourensia co-occurring native species suggest that QACs accumulation may be considered as a community-specific ecophysiological trait in these xerophytic environments. .Fil: Piazza, Leonardo A.. Universidad de Buenos Aires. Facultad de Agronomia. Sede Polo Universitario Punilla Centro; ArgentinaFil: LĂłpez, D.. Universidad de Buenos Aires. Facultad de Agronomia. Sede Polo Universitario Punilla Centro; ArgentinaFil: Silva, Mariana Paola. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Universidad de Buenos Aires. Facultad de Agronomia. Sede Polo Universitario Punilla Centro; ArgentinaFil: Lopez Rivilli, Marisa Juana. Universidad de Buenos Aires. Facultad de Agronomia. Sede Polo Universitario Punilla Centro; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Cantero, Juan Jose. Universidad Nacional de RĂo Cuarto. Facultad de AgronomĂa y Veterinaria; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba. Instituto Multidisciplinario de BiologĂa Vegetal. Universidad Nacional de CĂłrdoba. Facultad de Ciencias Exactas FĂsicas y Naturales. Instituto Multidisciplinario de BiologĂa Vegetal; ArgentinaFil: Tourn, G. M.. Universidad de Buenos Aires. Facultad de Agronomia. Sede Polo Universitario Punilla Centro; ArgentinaFil: Scopel, Ana Leonor. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Instituto de Investigaciones en Biociencias AgrĂcolas y Ambientales. Universidad de Buenos Aires. Facultad de AgronomĂa. Instituto de Investigaciones en Biociencias AgrĂcolas y Ambientales; Argentin
Magnetic and magnetorheological properties of nanofiber suspensions
International audienceIn this work the preparation and characterization of magnetorheological (MR) fluids constituted by CoNi nanofibers (56 nm length, 6.6 nm width) are reported. The properties of these new fluids were characterized by usual techniques (including magnetometry and magnetorheology). The results were compared with those obtained for conventional suspensions constituted by CoNi nanosperes
Fermionic Chern-Simons theory for the Fractional Quantum Hall Effect in Bilayers
We generalize the fermion Chern-Simons theory for the Fractional Hall Effect
(FQHE) which we developed before, to the case of bilayer systems. We study the
complete dynamic response of these systems and predict the experimentally
accessible optical properties. In general, for the so called
states, we find that the spectrum of collective excitations has a gap, and the
wave function has the Jastrow-Slater form, with the exponents determined by the
coefficients , and . We also find that the states, {\it
i.~e.~}, those states whose filling fraction is , have a gapless mode
which may be related with the spontaneous appearance of the interlayer
coherence. Our results also indicate that the gapless mode makes a contribution
to the wave function of the states analogous to the phonon
contribution to the wave function of superfluid . We calculate the
Hall conductance, and the charge and statistics of the quasiparticles. We also
present an generalization of this theory relevant to spin unpolarized
or partially polarized single layers.Comment: 55 pages, Urbana Prepin
Chern_simons Theory of the Anisotropic Quantum Heisenberg Antiferromagnet on a Square Lattice
We consider the anisotropic quantum Heisenberg antiferromagnet (with
anisotropy ) on a square lattice using a Chern-Simons (or
Wigner-Jordan) approach. We show that the Average Field Approximation (AFA)
yields a phase diagram with two phases: a Ne{\`e}l state for
and a flux phase for separated by a
second order transition at . We show that this phase diagram does
not describe the regime of the antiferromagnet. Fluctuations around the
AFA induce relevant operators which yield the correct phase diagram. We find an
equivalence between the antiferromagnet and a relativistic field theory of two
self-interacting Dirac fermions coupled to a Chern-Simons gauge field. The
field theory has a phase diagram with the correct number of Goldstone modes in
each regime and a phase transition at a critical coupling . We identify this transition with the isotropic Heisenberg point. It
has a non-vanishing Ne{\` e}l order parameter, which drops to zero
discontinuously for .Comment: 53 pages, one figure available upon request, Revte
Changes in interleukin-1 signal modulators induced by 3,4-methylenedioxymethamphetamine (MDMA): regulation by CB2 receptors and implications for neurotoxicity
Effect of pasture in oak and chestnut groves on chemical and sensorial traits of cured lard of Cinta Senese pigs
The objective of this study was to evaluate the effect of pasture in oak and chestnut groves on the chemical and sensorial traits of cured lard. Thirty Cinta Senese barrows (124kg of l.w. on average) were allotted to three groups: one group (CONC) was reared outdoors in a confined area and fed commercial feedstuff. The other two groups were raised under free-range conditions on acorns (AC) or chestnuts (CH). At slaughtering (148kg of LW) the backfat was seasoned for 60 days to obtained cured lard. Results demonstrated that the lard of CH and AC respect to CONC group was the richest in MUFA (46.9 and 47.76 vs 44.78% respectively) because of the higher content of oleic acid (44.2 and 44.91 vs 42.05%, P<0.05, respectively). CH showed a higher percentage of PUFA-n3 than AC and CONC (1.18 vs 1.06 and 1.03%, P<0.05, respectively), a lower content of α-tocopherol (9.77 vs 14.46 and 13.31ÎŒ/g, P<0.05 respectively) and a higher content of Îł-tocopherol (13.73 vs 6.02 and 4.32ÎŒ/g, P<0.05, respectively). As regards sensorial traits, the lard of CH and AC groups exhibited a lower value of pinkness than CONC (29.3 and 32.4 vs 49.2, P<0.05, respectively) and higher scores of yellowness (31.4 and 28.6 vs 18.6, P<0.05, respectively) and oiliness (37.0 and 33.7 vs 24.0, P<0.05, respectively). The pasture in the acorn and chestnut groves affected the chemical traits of lard, prevalently the composition of fatty acids . The consumption of acorns or chestnuts led to a higher content of oleic acid with respect to concentrate, affecting some sensorial traits of lard
Generalised Chern-Simons Theory of Composite Fermions in Bilayer Hall Systems
We present a field theory of Jain's composite fermion model as generalised to
the bilayer quantum Hall systems. We define operators which create composite
fermions and write the Hamiltonian exactly in terms of these operators. This is
seen to be a complexified version of the familiar Chern Simons theory. In the
mean-field approximation, the composite fermions feel a modified effective
magnetic field exactly as happens in usual Chern Simons theories, and plateaus
are predicted at the same values of filling factors as Lopez and Fradkin and
Halperin . But unlike normal Chern Simons theories, we obtain all features of
the first-quantised wavefunctions including its phase, modulus and correct
gaussian factors at the mean field level. The familiar Jain relations for
monolayers and the Halperin wavefunction for bilayers come out as special
cases.Comment: Revtex file; 20 pages after processing; no figure
Ribavirin as a First Treatment Approach for Hepatitis E Virus Infection in Transplant Recipient Patients
The hepatitis E virus (HEV) is the major cause of acute hepatitis of viral origin worldwide. Despite its usual course as an asymptomatic self-limited hepatitis, there are highly susceptible populations, such as those with underlying immunosuppression, which could develop chronic hepatitis. In this situation, implementation of therapy is mandatory in the sense to facilitate viral clearance. Currently, there are no specific drugs approved for HEV infection, but ribavirin (RBV), the drug of choice, is used for off-label treatment. Here, we present two cases of chronic HEV infection in transplant patients, reviewing and discussing the therapeutic approach available in the literature. The use of RBV for the treatment of an HEV infection in organ transplant patients seems to be effective. The recommendation of 12 weeks of therapy is adequate in terms of efficacy. Nevertheless, there are important issues that urgently need to be assessed, such as optimal duration of therapy and drug dosage
Fiber Optic Sensing System for Temperature and Gas Monitoring in Coal Waste Pile Combustion Environments
International audienceIt is presented an optical fiber sensing system projected to operate in the demanding conditions associated with coal waste piles in combustion. Distributed temperature measurement and spot gas sensing are requirements for such a system. A field prototype has been installed and is continuously gathering data, which will input a geological model of the coal waste piles in combustion aiming to understand their dynamics and evolution. Results are presented on distributed temperature and ammonia measurement, being noticed any significant methane emission in the short time period considered. Carbon dioxide is also a targeted gas for measurement, with validated results available soon. The assessment of this technology as an effective and reliable tool to address the problem of monitoring coal waste piles in combustion opens the possibility of its widespread application in view of the worldwide presence of coal related fires
- âŠ