En este trabajo se evalúa la eficacia de un proceso de formación basado en la resolución de problemas matemáticos mediante la experimentación y el uso de materiales manipulativos, sobre el dominio ...afectivo, definido como creencias, emociones y actitudes hacia las matemáticas de futuros maestros. Se ha utilizado un diseño preexperimental con grupo pretest y postest sobre una muestra de 91 estudiantes de los grados en Maestro en Educación Infantil y Primaria. El instrumento utilizado es un autoinforme sobre creencias, emociones y actitudes acerca de las matemáticas validado previamente. El diseño de instrucción ha incidido de forma positiva en el dominio afectivo, pues ha generado cambios significativos en sus creencias acerca de la naturaleza de las matemáticas y de su enseñanza y aprendizaje, del papel del docente, de ellos mismos como aprendices de matemáticas y en sus actitudes y emociones, pues muestran un mayor interés, satisfacción y seguridad como futuros maestros.
Serotonin (5-HT) modulates key aspects of the immune system. However, its precise function and the receptors involved in the observed effects have remained elusive. Among the different serotonin ...receptors, 5-HT1A plays an important role in the immune system given its presence in cells involved in both the innate and adaptive immune responses, but its actual levels of expression under different conditions have not been comprehensively studied due to the lack of suitable tools. To further clarify the role of 5-HT1A receptor in the immune system, we have developed a fluorescent small molecule probe that enables the direct study of the receptor levels in native cells. This probe allows direct profiling of the receptor expression in immune cells using flow cytometry. Our results show that important subsets of immune cells including human monocytes and dendritic cells express functional 5-HT1A and that its activation is associated with anti-inflammatory signaling. Furthermore, application of the probe to the experimental autoimmune encephalomyelitis model of multiple sclerosis demonstrates its potential to detect the specific overexpression of the 5-HT1A receptor in CD4+ T cells. Accordingly, the probe reported herein represents a useful tool whose use can be extended to study the levels of 5-HT1A receptor in ex vivo samples of different immune system conditions.
Antibiotic stewardship programs (ASP) have already demonstrated clinical benefits. We aimed to describe the Point Prevalence Surveys (PPS) methodology implemented in our hospital as an efficient tool ...to guide ASP strategies. Annually repeated PPS were conducted from 2012 to 2019 at a 750-bed university hospital in South Spain. Key quality indicators and inappropriateness of antimicrobial treatment, defined strictly according to local guidelines, were described. Variables associated with inappropriate treatment were identified by bi/multivariable analysis. A total of 1,600 patients were included. We found that 49% of the prescriptions were inappropriate due to unnecessary treatment (14%), not first line drug recommended (14%), inadequate drug according to microbiological results (9%), unsuitable doses (8%), route (3%) or duration (7%). Samples collection presented a significant protective effect together with sepsis presentation at onset and intensive care unit admission. However, age, receiving an empirical treatment and an unknown or urinary source of the infections treated were independent risk factors for inappropriateness. Site and severity of infection were documented in medical charts by prescribers (75 and 61% respectively). PPS may allow identifying the main risk factors for inappropriateness. This simple methodology may be useful for ASP to select modifiable factors to be prioritized for targeted interventions.
Excessive fat accumulation within the liver is known as "simple hepatic steatosis", which is the most benign form of non-alcoholic fatty liver disease (NAFLD). The aim of the present study was to ...determine whether pterostilbene improves this hepatic alteration in Zucker (
/
) rats. Animals were distributed in two experimental groups (
= 10) and fed a standard laboratory diet. Rats in the pterostilbene group were given a dose of 30 mg/kg body weight/d for six weeks. After sacrifice, serum glucose, transaminase, and insulin concentrations were quantified and the liver triacylglycerol content and fatty acid profile was analyzed. Different pathways of triacylglycerol metabolism in liver were studied, including fatty acid synthesis and oxidation, triglyceride assembly, fatty acid uptake, and glucose uptake. With pterostilbene administration, a reduction in insulin concentrations (consequently in the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR)) and hepatic triacylglycerol content were observed. No effects were observed in pterostilbene-treated rats in the activity of
lipogenesis enzymes. An improvement in the fatty acid profile was observed in pterostilbene-treated rats. In conclusion, pterostilbene is a useful molecule to reduce liver steatosis. Its delipidating effect is due, at least in part, to reduced fatty acid availability and triacylglycerol synthesis, as well as to an increased very low-density lipoprotein assembly and fatty acid oxidation.
Aims
The AT(N) classification system not only improved the biological characterization of Alzheimer's disease (AD) but also raised challenges for its clinical application. Unbiased, data‐driven ...techniques such as clustering may help optimize it, rendering informative categories on biomarkers' values.
Methods
We compared the diagnostic and prognostic abilities of CSF biomarkers clustering results against their AT(N) classification. We studied clinical (patients from our center) and research (Alzheimer's Disease Neuroimaging Initiative) cohorts. The studied CSF biomarkers included Aβ(1–42), Aβ(1–42)/Aβ(1–40) ratio, tTau, and pTau.
Results
The optimal solution yielded three clusters in both cohorts, significantly different in diagnosis, AT(N) classification, values distribution, and survival. We defined these three CSF groups as (i) non‐defined or unrelated to AD, (ii) early stages and/or more delayed risk of conversion to dementia, and (iii) more severe cognitive impairment subjects with faster progression to dementia.
Conclusion
We propose this data‐driven three‐group classification as a meaningful and straightforward approach to evaluating the risk of conversion to dementia, complementary to the AT(N) system classification.
We compared CSF biomarkers clustering results against their AT(N) classification in two cohorts. Clustering yielded three groups: non‐defined AD, early stages with delayed risk of dementia, and severe cognitive impairment subjects with faster progression to dementia. We propose this data‐driven categorization as a meaningful and straightforward approach to evaluating dementia risk, complementary to the AT(N) system classification.
El objetivo de este estudio fue analizar la estrategia que instrumentan 19 microempresas que elaboran quesos artesanales en el trópico de México. El análisis se llevó a cabo mediante el cálculo de un ...índice de estrategia a partir de la detección de las acciones implementadas en los ámbitos de colaboración, innovación, canales de comercialización, supervivencia financiera, diferenciación y relación con el consumidor, para comparar la combinación de estrategias con la que se enfrentan a un mercado cambiante. A partir de un análisis de conglomerados no jerárquico, cuya variable de agrupación fue el índice de estrategia por categoría, se diferenció el comportamiento de cada grupo de microempresas. Resultaron cuatro mecanismos a partir de la combinación de estrategias que cada grupo de microempresas lleva a cabo. Se concluyó que, para sobrevivir en el mercado, estas microempresas han desarrollado acciones estratégicas diferenciadas, entre las que predominan las de canal de venta, en tres de cuatro conglomerados, y las de colaboración, en dos de cuatro conglomerados. No se detectaron diferencias entre grupos respecto a las acciones relacionadas con la sobrevivencia financiera y con la diferenciación.
The replacement of pyridine by 1-methyl-imidazol in the arms of a N
6
-tripodal ligand allows preparing two new Co
II
complexes with quasi-ideal triangular prismatic geometry, which behave as SIMs ...(Single Ion Magnets) at zero dc field with enhanced axial magnetic anisotropy, magnetic relaxation times and magnetic hysteresis.
We have demonstrated that the smaller the distortion of the coordination sphere from the ideal trigonal prismatic geometry in mononuclear Co
II
complexes, the larger the axial anisotropy, the relaxation times and the magnetic hysteresis.
Monoacylglycerols (MAG) containing polyunsaturated fatty acids (PUFA) have been synthesized by glycerolysis of anchovy oil using Lipozyme RM-IM in a solvent-free system. The experimental conditions, ...reaction temperature, substrate molar ratio (glycerol/triacylglycerol, Gly/TAG) and enzyme concentration were studied. A response surface methodology was employed to analyze the effect of the individual variables on MAG production and oxidative stability with respect to induction time. The operating conditions that simultaneously optimized MAG yields and oxidative stability were a reaction temperature of 40 °C, a Gly/TAG molar ratio of 2:1 and 6% enzyme load. The yield obtained was 20.34% of MAG (with 12.12% of 2-MAG) and an induction time of 1.88 h.
•PUFA-rich monoacylglycerols (MAG) are of interest due to their health benefits.•MAG were produced by enzymatic glycerolysis of anchovy oil in solvent-free medium.•The effect of process parameters in yield and oxidative stability of MAG was studied.•The desirability function suitably maximized MAG production and oxidative stability.•An oil with 20% of MAG (12% of 2-MAG) and an induction time of 1.9 h was obtained.
The replacement of pyridine by 1-methyl-imidazol in the arms of a N6-tripodal ligand allows preparing two new CoII complexes with quasi-ideal triangular prismatic geometry, which behave as SIMs ...(Single Ion Magnets) at zero dc field with enhanced axial magnetic anisotropy, magnetic relaxation times and magnetic hysteresis.
The complexes Co(L)X·S (X = CoCl
4
2−
, S = CH
3
CN (
1
); X = ZnCl
4
2−
, S = CH
3
OH (
2
)), Co(L)X
2
·S (X = ClO
4
−
, S = 2CH
3
OH (
3
) and X = BF
4
−
(
4
)) and Co(L)(NCS)
2
(
5
), where L = ...the N
6
-tripodal ligand tris(pyridylhydrazonyl)phosphorylsulfide, were prepared and studied by X-ray crystallography, ac and dc magnetic data, FIRMS and HFEPR spectra, and theoretical calculations. On passing from
1
to
4
, the change of the counteranion decreases slightly the distortion of the CoN
6
coordination polyhedron from trigonal prismatic to octahedral, with a parallel increase of the easy-axis magnetic anisotropy. Compound
1
does not show slow magnetic relaxation, even in the presence of a dc magnetic field, due to fast QTM triggered by dipolar interactions. Although the complexes
2-4
show a weak frequency and temperature dependence of the ac susceptibility below 10 K at zero field, they exhibit slow relaxation and single-molecule magnet (SMM) behaviour under the corresponding optimal field. The relaxation of the magnetization takes place mainly through a Raman relaxation process above 4 K, whereas below this temperature QTM and/or direct processes dominate. The relaxation time increases with the parallel increase of the uniaxial anisotropy on passing from
1
to
4
. The width of the hysteresis for the trigonal prismatic complexes at 0.4 K decreases in the order
3
>
2
>
4
>
1
, which is due to combined effects of QTM relaxation and axial anisotropy. Magnetic dilution of complexes
3
and
4
with Zn
II
triggers the slow relaxation of the magnetization at zero-field, so that these complexes can be considered as "hidden mononuclear SMMs". Compound
5
, with a compressed octahedral geometry, exhibits easy-plane magnetic anisotropy (
D
= +34.7 cm
−1
), and it is a field-induced mononuclear SMM with magnetization relaxation faster than compounds
2-4
and a smaller hysteresis loop.
A N
6
-tripodal ligand allows the preparation of a family of prismatic mononuclear cationic Co
II
complexes with SMM behavior. Their axial anisotropy, magnetic relaxation and hysteresis width are modulated by the anion effects on the crystal structure.
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