1,259 research outputs found
Existence of weak-renormalized solution for a nonlinear system
We prove an existence result for a coupled system of the reactiondiffusion kind. The fact that no growth condition is assumed on some nonlinear terms motivates the search of a weak-renormalized solution.We prove an existence result for a coupled system of the reactiondiffusion kind. The fact that no growth condition is assumed on some nonlinear terms motivates the search of a weak-renormalized solution
ALGUNAS APLICACIONES DE LA TEORÃA DE SISTEMAS AL DESARROLLO ORGANIZACIONAL
In the routine of daily activities, and the eagerness to obtain quantitative results, organizations run the risk of becoming absorbed in reductionist notions concerning their task environments (internal and external). This position has counterproductive effects on the learning and renovation capacities of the own organizations, reducing their success and permanence possibilities. The properties and tools of the systemic approach provide information about relevant issues and problems that, in countless cases, are unnoticed by administration and management schemes of rationalist character. Different arguments holding this thesis are exposed through the analysis of several topics and examples.Holism, organizational development, organizational learning, strategic planning, systemic thinking, systems theory, task environment., Agribusiness,
82: Severe Hemorrhagic Cystitis (HC) After Allogeneic Hematopoeitic Stem Cell Transplantation (HSCT): Incidence and Risk Factors
With the purpose to investigate the radio emission of new ultracool objects,
we carried out a targeted search in the recently discovered system VHS
J125601.92125723.9 (hereafter VHS 12561257); this system is composed by
an equal-mass M7.5 binary and a L7 low-mass substellar object located at only
15.8\,pc. We observed in phase-reference mode the system VHS 12561257 with
the Karl G. Jansky Very Large Array at - and - band and with the European
VLBI Network at -band in several epochs during 2015 and 2016. We discovered
radio emission at -band spatially coincident with the equal-mass M7.5 binary
with a flux density of 60 Jy. We determined a spectral index between 8 and 12 GHz, suggesting that non-thermal,
optically-thin, synchrotron or gyrosynchrotron radiation is responsible for the
observed radio emission. Interestingly, no signal is seen at -band where we
set a 3- upper limit of 20 Jy. This might be explained by strong
variability of the binary or self-absorption at this frequency. By adopting the
latter scenario and gyrosynchrotron radiation, we constrain the turnover
frequency to be in the interval 5--8.5 GHz, from which we infer the presence of
kG-intense magnetic fields in the M7.5 binary. Our data impose a 3-
upper bound to the radio flux density of the L7 object of 9 Jy at 10\,GHz.Comment: 6 pages, 4 figures. Accepted for publication in A&
Composition, nanostructure, and optical properties of silver and silver-copper lusters
Lusters are composite thin layers of coinage metal nanoparticles in glass displaying peculiar optical
properties and obtained by a process involving ionic exchange, diffusion, and crystallization. In
particular, the origin of the high reflectance (golden-shine) shown by those layers has been subject of
some discussion. It has been attributed to either the presence of larger particles, thinner multiple
layers or higher volume fraction of nanoparticles. The object of this paper is to clarify this for which
a set of laboratory designed lusters are analysed by Rutherford backscattering spectroscopy,
transmission electron microscopy, x-ray diffraction, and ultraviolet-visible spectroscopy. Model
calculations and numerical simulations using the finite difference time domain method were also
performed to evaluate the optical properties. Finally, the correlation between synthesis conditions,
nanostructure, and optical properties is obtained for these materials
Sociological and Human Developmental Explanations of Crime: Conflict or Consensus
This paper examines multidisciplinary correlates of delinquency in an attempt to integrate sociological and environmental theories of crime with human developmental and biological explanations of crime. Structural equation models are applied to assess links among biological, psychological, and environmental variables collected prospectively from birth through age 17 on a sample of 800 black children at high risk for learning and behavioral disorders. Results show that for both males and females, aggression and disciplinary problems in school during adolescence are the strongest predictors of repeat offense behavior. Whereas school achievement and family income and stability are also significant predictors of delinquency for males, early physical development is the next strongest predictor for females. Results indicate that some effects on delinquency also vary during different ages. It is suggested that behavioral and learning disorders have both sociological and developmental correlates and that adequate educational resources are necessary to ensure channels of legitimate opportunities for high-risk youths
Pseudo-single crystal electrochemistry on polycrystalline electrodes : visualizing activity at grains and grain boundaries on platinum for the Fe2+/Fe3+ redox reaction
The influence of electrode surface structure on electrochemical reaction rates and mechanisms is a major theme in electrochemical research, especially as electrodes with inherent structural heterogeneities are used ubiquitously. Yet, probing local electrochemistry and surface structure at complex surfaces is challenging. In this paper, high spatial resolution scanning electrochemical cell microscopy (SECCM) complemented with electron backscatter diffraction (EBSD) is demonstrated as a means of performing ‘pseudo-single-crystal’ electrochemical measurements at individual grains of a polycrystalline platinum electrode, while also allowing grain boundaries to be probed. Using the Fe2+/3+ couple as an illustrative case, a strong correlation is found between local surface structure and electrochemical activity. Variations in electrochemical activity for individual high index grains, visualized in a weakly adsorbing perchlorate medium, show that there is higher activity on grains with a significant (101) orientation contribution, compared to those with (001) and (111) contribution, consistent with findings on single-crystal electrodes. Interestingly, for Fe2+ oxidation in a sulfate medium a different pattern of activity emerges. Here, SECCM reveals only minor variations in activity between individual grains, again consistent with single-crystal studies, with a greatly enhanced activity at grain boundaries. This suggests that these sites may contribute significantly to the overall electrochemical behavior measured on the macroscale
Abnormalities on 1q and 7q are associated with poor outcome in sporadic Burkitt's lymphoma. A cytogenetic and comparative genomic hybridization study
Comparative genomic hybridization (CGH) studies have demonstrated a high incidence of chromosomal imbalances in non-Hodgkin's lymphoma. However, the information on the genomic imbalances in Burkitt's Lymphoma (BL) is scanty. Conventional cytogenetics was performed in 34 cases, and long-distance PCR for t(8;14) was performed in 18 cases. A total of 170 changes were present with a median of four changes per case (range 1-22). Gains of chromosomal material (143) were more frequent than amplifications (5) or losses (22). The most frequent aberrations were gains on chromosomes 12q (26%), Xq (22%), 22q (20%), 20q (17%) and 9q (15%). Losses predominantly involved chromosomes 13q (17%) and 4q (9%). High-level amplifications were present in the regions 1q23-31 (three cases), 6p12-p25 and 8p22-p23. Upon comparing BL vs Burkitt's cell leukemia (BCL), the latter had more changes (mean 4.3 +/- 2.2) than BL (mean 2.7 +/- 3.2). In addition, BCL cases showed more frequently gains on 8q, 9q, 14q, 20q, and 20q, 9q, 8q and 14q, as well as losses on 13q and 4q. Concerning outcome, the presence of abnormalities on 1q (ascertained either by cytogenetics or by CGH), and imbalances on 7q (P=0.01) were associated with a short survival
On natural metalinguistic abilities in aphasia: a preliminary study
Natural metalinguistic abilities, which are put into play without explicit instructions, constitute the cognitive basis for a 'reflexive' use of language, a particular manifestation of the executive function when applied to language and verbal behaviour. This reflexive use entails a specific attentional activity by speakers and hearers with regard to linguistic outputs, and an intentional experience-based control over the language use. Putting into play natural metalinguistic abilities can be considered a significant factor for explaining different kinds of adaptive processes. Our results permit us to conclude that an impairment of metalinguistic abilities is involved in aphasia to different degrees. Moreover, the examination of preserved metalinguistic abilities provides an alternative way for assessing the degree of severity of impaired communicative behaviour by people with aphasia. Our procedure, presumably, will also be useful for suggesting new factors when designing therapeutic programmes
Surface imaging of cool evolved stars in the era of the ELT
Cool evolved stars are the main source of chemical enrichment of the
interstellar medium. Understanding their mass loss offers a unique opportunity
to study the cycle of matter. We discuss interferometric studies and their
comparison to latest state-of-the-art dynamic model atmospheres. They show
broad agreement for asymptotic giant branch stars. For red supergiants,
however, current models cannot explain observed extensions by far, pointing to
missing physical processes in their models, and uncertainties in our general
understanding of mass loss. We present ongoing imaging and time-series
observations that may provide the strongest constraint and may help to identify
missing dynamic processes. VLTI studies will remain the highest spatial
resolution observations at ESO into the ELT era, complemented by ALMA
observations. We discuss crucial improvements in both instrumental and
operational areas for surface imaging of cool evolved stars in the era of the
ELT.Comment: 5 pages, 5 figures. Contribution at ESO Workshop "The Very Large
Telescope in 2030", held at ESO Garching, June 17-20, 201
LMO2 expression reflects the different stages of blast maturation and genetic features in B-cell acute lymphoblastic leukemia and predicts clinical outcome
BACKGROUND: LMO2 is highly expressed at the most immature stages of lymphopoiesis. In T-lymphocytes, aberrant LMO2 expression beyond those stages leads to T-cell acute lymphoblastic leukemia, while in B cells LMO2 is also expressed in germinal center lymphocytes and diffuse large B-cell lymphomas, where it predicts better clinical outcome. The implication of LMO2 in B-cell acute lymphoblastic leukemia must still be explored.
DESIGN AND METHODS: We measured LMO2 expression by real time RT-PCR in 247 acute lymphoblastic leukemia patient samples with cytogenetic data (144 of them also with survival and immunophenotypical data) and in normal hematopoietic and lymphoid cells.
RESULTS: B-cell acute lymphoblastic leukemia cases expressed variable levels of LMO2 depending on immunophenotypical and cytogenetic features. Thus, the most immature subtype, pro-B cells, displayed three-fold higher LMO2 expression than pre-B cells, common-CD10+ or mature subtypes. Additionally, cases with TEL-AML1 or MLL rearrangements exhibited two-fold higher LMO2 expression compared to cases with BCR-ABL rearrangements or hyperdyploid karyotype. Clinically, high LMO2 expression correlated with better overall survival in adult patients (5-year survival rate 64.8% (42.5%-87.1%) vs. 25.8% (10.9%-40.7%), P= 0.001) and constituted a favorable independent prognostic factor in B-ALL with normal karyotype: 5-year survival rate 80.3% (66.4%-94.2%) vs. 63.0% (46.1%-79.9%) (P= 0.043).
CONCLUSIONS: Our data indicate that LMO2 expression depends on the molecular features and the differentiation stage of B-cell acute lymphoblastic leukemia cells. Furthermore, assessment of LMO2 expression in adult patients with a normal karyotype, a group which lacks molecular prognostic factors, could be of clinical relevance
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