530 research outputs found
The Influence of Silicon Nanoclusters on the Optical Properties of a-SiNx Samples: A Theoretical Study
By means of ab-initio calculations we investigate the optical properties of
pure a-SiN samples, with , and samples embedding silicon
nanoclusters (NCs) of diameter nm. In the pure samples
the optical absorption gap and the radiative recombination rate vary according
to the concentration of Si-N bonds. In the presence of NCs the radiative rate
of the samples is barely affected, indicating that the intense
photoluminescence of experimental samples is mostly due to the matrix itself
rather than to the NCs. Besides, we evidence an important role of Si-N-Si bonds
at the NC/matrix interface in the observed photoluminescence trend
Helping carers to care: the 10/66 dementia research group's randomized control trial of a caregiver intervention in Peru
OBJECTIVE
There is a need, in the absence of formal services, to design interventions aimed at improving the lives of people with dementia and their families. This study tested the effectiveness of the 10/66 caregiver intervention among people with dementia and their caregivers in Lima, Peru.
METHOD
Design/participants: a randomized controlled trial was performed involving 58 caregivers of people with dementia that received the intervention in the beginning of the trial (n = 29) or six months later (n = 29). The intervention consisted of three modules: 1) assessment (one session); 2) basic education about dementia (two sessions); and 3) training regarding specific problem behaviors (two sessions). Main outcome measures: Caregivers and patients with dementia were assessed at baseline and after six months. For caregivers, the measures included strain (Zarit Burden Interview), psychological distress (SRQ-20), and quality of life (WHOQOL-BREF). Dementia patients completed scales assessing behavioral and psychological symptoms (NPI-Q) and quality of life (DEMQOL).
RESULTS
Caregivers in the intervention group reported significantly decreased strain measures six months after the intervention compared to controls. No group differences were found in respect to the caregivers' psychological distress and to quality of life in both caregivers and patients.
CONCLUSION
The 10/66 intervention seems to be as effective as similar interventions used in more developed countries
La biodiversitÃ
Il tema ci consente di affrontare l’evoluzione
del rapporto tra terra e alimentazione, osservando
i cambiamenti che hanno interessato le tecniche di
produzione e l’attenzione ai problemi legati alla salute
e alla tutela dell’ambiente. La vita delle generazioni
passate ha sempre avuto come unico centro
di riferimento la terra ed i suoi frutti: possedere un
appezzamento di terra costituiva una enorme ricchezza
perché garantiva il necessario sostentamento
per una o più famiglie. La presenza di animali
da cortile o di bestiame forniva un contributo allo
svolgimento delle attività nei campi e consentiva di
variare i pasti da presentare a tavola. Il rapporto del
cibo con la terra era diretto, non subiva alcun tipo di
passaggio, se non per raggiungere il mercato o la fiera
dei paesi limitrofi, dove si proponevano la frutta e
la verdura di stagione, il latte prodotto in eccedenza
rispetto al fabbisogno domestico, le uova o la carne
macellata direttamente dall’allevatore, sebbene molto
più raramente
Exchange-spring behavior in bimagnetic CoFe2O4/CoFe2 nanocomposite
In this work we report a study of the magnetic behavior of ferrimagnetic
oxide CoFe2O4 and ferrimagnetic oxide/ferromagnetic metal CoFe2O4/CoFe2
nanocomposites. The latter compound is a good system to study hard
ferrimagnet/soft ferromagnet exchange coupling. Two steps were used to
synthesize the bimagnetic CoFe2O4/CoFe2 nanocomposites: (i) first preparation
of CoFe2O4 nanoparticles using the a simple hydrothermal method and (ii) second
reduction reaction of cobalt ferrite nanoparticles using activated charcoal in
inert atmosphere and high temperature. The phase structures, particle sizes,
morphology, and magnetic properties of CoFe2O4 nanoparticles have been
investigated by X-Ray diffraction (XRD), Mossbauer spectroscopy (MS),
transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM)
with applied field up to 3.0 kOe at room temperature and 50K. The mean diameter
of CoFe2O4 particles is about 16 nm. Mossbauer spectra reveal two sites for
Fe3+. One site is related to Fe in an octahedral coordination and the other one
to the Fe3+ in a tetrahedral coordination, as expected for a spinel crystal
structure of CoFe2O4. TEM measurements of nanocomposite show the formation of a
thin shell of CoFe2 on the cobalt ferrite and indicate that the nanoparticles
increase to about 100 nm. The magnetization of nanocomposite showed hysteresis
loop that is characteristic of the exchange spring systems. A maximum energy
product (BH)max of 1.22 MGOe was achieved at room temperature for CoFe2O4/CoFe2
nanocomposites, which is about 115% higher than the value obtained for CoFe2O4
precursor. The exchange-spring interaction and the enhancement of product
(BH)max in nanocomposite CoFe2O4/CoFe2 have been discussed.Comment: 9 pages, 10 figure
The length of the expressed 3′ UTR is an intermediate molecular phenotype linking genetic variants to complex diseases
Non-invasive assessment of the seasonal stress response to veterinary procedures and transportation of zoo-housed lesser anteater (Tamandua tetradactyla)
Management procedures affect behavioural and physiological stress responses of wild mammals under human care. According to the Reactive Scope Model, normal values are presumed to exist within predictive and reactive ranges. First, stress parameters of zoo-housed adult Tamandua tetradactyla were evaluated in winter and summer (29 days each), determining the level of behaviour and/or physiological parameters needed to respond to predictable environmental changes. Secondly, the effects of veterinary procedures and transportation were studied in both seasons. Non-invasive methods were applied, assessing behaviour through videos and adrenocortical activity by faecal glucocorticoid metabolites (FGMs). Lesser anteaters exhibited seasonality (summer > winter) in some behavioural parameters, such as nocturnal activities, as well as in the activity cycle (e.g., acrophase) and FGMs. A veterinary check elicited an increase in total activity (TA), natural behaviours and repetitive locomotion and affected the activity cycle, particularly in summer. Transport produced changes in TA, nocturnal and natural activity and some variables of the activity cycle, mostly during summer. Although the effects of routine management procedures were different from each other and presumably stressful, they elicited changes only at the behavioural level, which was greater during summer. The differences observed according to non-invasive methodologies highlight the importance of a multidisciplinary approach in this context and suggest that it is unlikely that individual welfare was affectedFil: Eguizabal, Gabina Victoria. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, FÃsicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas FÃsicas y Naturales. Instituto de Ciencias y TecnologÃa de los Alimentos; Argentina. Parque de la Biodiversidad (ex JardÃn Zoológico Córdoba); ArgentinaFil: Superina, Mariella. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Mendoza. Instituto de Medicina y BiologÃa Experimental de Cuyo; ArgentinaFil: Palme, Rupert. Veterinarmedizinische Universitat Wien; AustriaFil: Asencio, Camila Julieta. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, FÃsicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas FÃsicas y Naturales. Instituto de Ciencias y TecnologÃa de los Alimentos; Argentina. Parque de la Biodiversidad (ex JardÃn Zoológico Córdoba); ArgentinaFil: Villarreal, Daniel P.. Parque de la Biodiversidad (ex JardÃn Zoológico Córdoba); ArgentinaFil: Borrelli, Luciana. Facultad de Ciencias Agrarias y Veterinarias ; Universidad Catolica de Salta; Argentina. Gobierno de la Provincia de Salta. Ministerio de Produccion Trabajo y Desarrollo Sustentable.; ArgentinaFil: Busso, Juan Manuel. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, FÃsicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas FÃsicas y Naturales. Instituto de Ciencias y TecnologÃa de los Alimentos; Argentina. Parque de la Biodiversidad (ex JardÃn Zoológico Córdoba); Argentin
Antibody-mediated blockade of JMJD6 interaction with collagen I exerts antifibrotic and antimetastatic activities
JMJD6 is known to localize in the nucleus, exerting histone arginine demethylase and lysyl hydroxylase activities. A novel localization of JMJD6 in the extracellular matrix, resulting from its secretion as a soluble protein, was unveiled by a new anti-JMJD6 mAb called P4E11, which was developed to identify new targets in the stroma. Recombinant JMJD6 binds with collagen type I (Coll-I), and distinct JMJD6 peptides interfere with collagen fibrillogenesis, collagen-fibronectin interaction, and adhesion of human tumor cells to the collagen substrate. P4E11 and collagen binding to JMJD6 are mutually exclusive because the amino acid sequences of JMJD6 necessary for the interaction with Coll-I are part of the conformational epitope recognized by P4E11. In mice injected with mouse 4T1 breast carcinoma cells, treatment with P4E11 reduced fibrosis at the primary tumor and prevented lung metastases. Reduction of fibrosis has also been documented in human breast and ovarian tumors (MDA-MB-231 and IGROV1, respectively) xenotransplanted into immunodeficient mice treated with P4E11. In summary, this study uncovers a new localization and function for JMJD6 that is most likely independent from its canonical enzymatic activities, and demonstrates that JMJD6 can functionally interact with Coll-I. P4E11 mAb, inhibiting JMJD6/Coll-I interaction, represents a new opportunity to target fibrotic and tumor diseases
Translating self-efficacy in job performance over time: The role of job crafting
This investigation intends to uncover the mechanisms linking self-efficacy to job performance by analyzing the mediating role of job crafting. A two-wave study on 465 white-collar workers was conducted, matching participants’ self-report data (i.e., self-efficacy and job crafting) with supervisory performance ratings. The structural equation model showed a positive reciprocal relationship between self-efficacy and crafting behaviors. In turn, job crafting predicted performance positively over time. More importantly, results confirmed the mediating role of crafting actions, which may represent the behavioral process underlying the positive effect of self-efficacy on individual outcomes. Practical implications for organizations, such as encouraging bottom-up job design or designing job-crafting interventions, and future research directions are also offered
Interferon γ–independent Rejection of Interleukin 12–transduced Carcinoma Cells Requires CD4+T Cells and Granulocyte/Macrophage Colony– stimulating Factor
We analyzed the ability of interferon (IFN)-
γ knockout mice (GKO) to reject a colon carcinoma
transduced with interleukin (IL)-12 genes (C26/IL-12). Although the absence of IFN-γ
impaired the early response and reduced the time to tumor onset in GKO mice, the overall tumor
take rate was similar to that of BALB/c mice. In GKO mice, C26/IL-12 tumors had a reduced
number of infiltrating leukocytes, especially CD8 and natural killer cells. Analysis of the
tumor site, draining nodes, and spleens of GKO mice revealed reduced expression of IFNinducible
protein 10 and monokine induced by
γ-IFN. Despite these defects, GKO mice that
rejected C26/IL-12 tumor, and mice that were primed in vivo with irradiated C26/IL-12 cells,
showed the same cytotoxic T lymphocyte activity but higher production of granulocyte/macrophage
colony–stimulating factor (GM-CSF) as compared with control BALB/c mice. Treatment
with monoclonal antibodies against GM-CSF abrogated tumor regression in GKO but
not in BALB/c mice. CD4 T lymphocytes, which proved unnecessary or suppressive during
rejection of C26/IL-12 cells in BALB/c mice, were required for tumor rejection in GKO
mice. CD4 T cell depletion was coupled with a decline in GM-CSF expression by lymphocytes
infiltrating the tumors or in the draining nodes, and with the reduction and disappearance
of granulocytes and CD8 T cells, respectively, in tumor nodules. These results suggest that
GM-CSF can substitute for IFN-γ
in maintaining the CD8–polymorphonuclear leukocyte
cross-talk that is a hallmark of tumor rejection
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