11,075 research outputs found
Efecto de la dosis de irradiación UV-C y tiempo de almacenamiento sobre las características fisicoquímicas, contenido de antocianinas, recuento de mohos y levaduras y aceptabilidad general en jugo de granada (punica granatum L.) variedad wonderful
Se evaluó el efecto de la dosis ( 18 y 36 kJ/L ) de irradiación de UV-C y
tiempo de almacenamiento a 2 ºC, en el pH, contenido de sólidos
solubles, contenido de antocianinas, recuento de mohos y levaduras y
aceptabilidad general en jugo de granada variedad Wonderful,
procedente de la provincia de Virú, Región La Libertad. Los frutos fueron
lavados, desinfectados con agua clorada 100 ppm y los arilos separados
manualmente. El jugo fue extraído en una pulpeadora con malla 0.5 mm.
Posteriormente el jugo fue almacenado a 5 ºC durante 30 min para lograr
la sedimentación de los sólidos suspendidos. El tratamiento de
irradiación con UV-C se realizó en un reactor que consta de una lámpara
UV-C de mercurio de baja presión ( Philips TUV-G16, 16 W ) , cubierta por
una funda de cuarzo e instalada concéntricamente en una carcasa de
acero inoxidable. El jugo tratado fue envasado y almacenado a 2 ºC
durante 14 días. Se determinó efecto significativo de la dosis de
irradiación con UV-C y el tiempo de almacenamiento sobre el contenido
de antocianinas y recuento de mohos y levaduras en jugo de granada
almacenado a 2 ºC, pero no en el pH y contenido de sólidos solubles. La
prueba preferencia pareada mostró diferencia significativa entre los
tratamientos sólo en el día 14 de almacenamiento refrigerado. La
muestra de jugo de granada irradiado con dosis de 18 kJ/L presentó
mayor contenido de antocianinas, recuento de mohos y levaduras,
dentro del límite permisible y mayor preferencia sensorial en el día 14 de
almacenamiento refrigerado.The effect of UV-C irradiation dosage ( 18 and 36 kJ/L ) and storage time
at 2 ºC was measured on pH, dry matter content, anthocyanins, mold and
yeast count and general acceptance in Grenade Juice, variety
Wonderful, originated from the province of Viru, region La Libertad. The
fruit was washed, disinfected with chlorinated water 100 ppm and the arils
manually separated. The juice was extracted using a pulper with a 0.5
mm net. Then, the juice was stored at 5 ºC for 30 min to achieve the
sedimentation of the dry matter. The UV-C irradiation treatment was
managed in a reactor with a low pressure UV-C mercury lamp
( Phillips TUV-G16, 16W ) , covered with a quartz cover and installed concentrically
in a stainless steel case. The juice was packed and stored at 2 ºC for 14
days. A significant effect for the UV-C irradiation dose and storage time
was determined over the content of anthocyanins and mold and yeast
count in Grenade juice stored at 2 ºC. On the other hand, there was no
significant effect for the pH or the dry matter content. Paired preference
test showed significant difference of the irradiated Grenade juice only at
the 14 th day of cold storage. The Grenade juice irradiated with doses of
18 kJ/L had a higher content of anthocyanins, yeast and mold count
within the permissible limit and higher sensory preference at the 14 day of cold storage. t
Characterizing the variation of propagation constants in multicore fibre
We demonstrate a numerical technique that can evaluate the core-to-core
variations in propagation constant in multicore fibre. Using a Markov Chain
Monte Carlo process, we replicate the interference patterns of light that has
coupled between the cores during propagation. We describe the algorithm and
verify its operation by successfully reconstructing target propagation
constants in a fictional fibre. Then we carry out a reconstruction of the
propagation constants in a real fibre containing 37 single-mode cores. We find
that the range of fractional propagation constant variation across the cores is
approximately .Comment: 17 pages; preprint format; 5 figures. Submitted to Optics Expres
Quantitative T1 mapping using multi-slice multi-shot inversion recovery EPI
An efficient multi-slice inversion–recovery EPI (MS-IR-EPI) sequence for fast, high spatial resolution, quantitative T1 mapping is presented, using a segmented simultaneous multi-slice acquisition, combined with slice order shifting across multiple acquisitions. The segmented acquisition minimises the effective TE and readout duration compared to a single-shot EPI scheme, reducing geometric distortions to provide high quality T1 maps with a narrow point-spread function. The precision and repeatability of MS-IR-EPI T1 measurements are assessed using both T1-calibrated and T2-calibrated ISMRM/NIST phantom spheres at 3 and 7 T and compared with single slice IR and MP2RAGE methods. Magnetization transfer (MT) effects of the spectrally-selective fat-suppression (FS) pulses required for in vivo imaging are shown to shorten the measured in-vivo T1 values. We model the effect of these fat suppression pulses on T1 measurements and show that the model can remove their MT contribution from the measured T1, thus providing accurate T1 quantification. High spatial resolution T1 maps of the human brain generated with MS-IR-EPI at 7 T are compared with those generated with the widely implemented MP2RAGE sequence. Our MS-IR-EPI sequence provides high SNR per unit time and sharper T1 maps than MP2RAGE, demonstrating the potential for ultra-high resolution T1 mapping and the improved discrimination of functionally relevant cortical areas in the human brain
Exploring the Relationship Between Impulsivity and Shame and Guilt-Proneness
The emotional experience of shame is characterized by negative self-evaluations, while guilt is characterized by negative behavioral-evaluations. Previous research has found shame to be the more maladaptive of these “self-conscious” emotions due to its association with various health-risk behaviors. This study investigated the relationship between impulsivity and shame and guilt-proneness in a population of undergraduate students. Whether this relationship predicts behavioral internalization or externalization was also examined. Students from the Texas A&M Psychology subject pool completed behavioral and self-report measures of impulsivity, shame-and guilt-proneness, and behavioral tendencies. Structural equation modeling was used to determine if shame and guilt-proneness mediate relationships between impulsivity and behavioral internalization and externalization
Tattoo Antenna Temporary Transfers Operating On-Skin (TATTOOS)
This paper discusses the development of RFID logo antennas based on the logos of Loughborough University and the University of Kent which can be tattooed directly onto the skin’s surface. Hence, this paper uses aesthetic principles to create functional wearable technology. Simulations of possible designs for the tattoo tags have been carried out to optimize their performance. Prototypes of the tag designs were fabricated and read range measurements with the transfer tattoos on a volunteers arm were carried out to test the performance. Measured Read ranges of approximately 0.5 m have been achieved with the antenna 10 µm from the body
GPER limits adverse changes to Ca2+ signalling and arrhythmogenic activity in ovariectomised guinea pig cardiomyocytes
Background: The increased risk of post-menopausal women developing abnormalities of heart function emphasises the requirement to understand the effect of declining oestrogen levels on cardiac electrophysiology and structure, and investigate possible therapeutic targets, namely the G protein-coupled oestrogen receptor 1 (GPER). Methods: Female guinea pigs underwent sham or ovariectomy (OVx) surgeries. Cardiomyocytes were isolated 150-days post-operatively. Membrane structure was assessed using di-8-ANEPPs staining and scanning ion conductance microscopy. Imunnohistochemistry (IHC) determined the localisation of oestrogen receptors. The effect of GPER activation on excitation-contraction coupling mechanisms were assessed using electrophysiological and fluorescence techniques. Downstream signalling proteins were investigated by western blot. Results: IHC staining confirmed the presence of nuclear oestrogen receptors and GPER, the latter prominently localised to the peri-nuclear region and having a clear striated pattern elsewhere in the cells. Following OVx, GPER expression increased and its activation reduced Ca2+ transient amplitude (by 40%) and sarcomere shortening (by 32%). In these cells, GPER activation reduced abnormal spontaneous Ca2+ activity, shortened action potential duration and limited drug-induced early after-depolarisation formation. Conclusion: In an animal species with comparable steroidogenesis and cardiac physiology to humans, we show the expression and localisation of all three oestrogen receptors in cardiac myocytes. We found that following oestrogen withdrawal, GPER expression increased and its activation limited arrhythmogenic behaviours in this low oestrogen state, indicating a potential cardioprotective role of this receptor in post-menopausal women
Identification of the bHLH Factor Math6 as a Novel Component of the Embryonic Pancreas Transcriptional Network
Background: Basic helix-loop-helix (bHLH) transcription factors play important roles in differentiation processes during embryonic development of vertebrates. In the pancreas, the atonal -related bHLH gene Neurogenin3 (Neurog3) controls endocrine cell fate specification in uncommitted progenitor cells. Therefore, it is likely that Neurog3-regulated factors will have important functions during pancreatic endocrine cell differentiation. The gene for the atonal -related bHLH factor Math6 was recognized as a potential target of Neurog3 in a genomic scale profiling during endocrine differentiation. Herein we have explored the role of Math6 during endocrine pancreas development. Results: We demonstrate that the Math6 gene is a direct target of Neurog3 in vitro and that, during mouse development, Math6 is expressed in both endocrine and exocrine pancreatic precursor cells. We have investigated the role of Math6 in endocrine differentiation by over-expressing this factor in pancreatic duct cells. Math6 possesses intrinsic transcriptional repressor activity and, in contrast to Neurog3 it does not induce the endocrine differentiation program; however, it can modulate some of the pro-endocrine functions of Neurog3 in this system. In addition, we show that Math6 is broadly expressed in mouse embryonic tissues and its expression is induced by tissue-specific bHLH genes other than Neurog3. Furthermore, inactivation of the Math6 gene in the mouse results in early embryonic lethality demonstrating an essential role of this factor in organismal development. Conclusions: These data demonstrate that Math6 is a novel component of the pancreatic transcriptional network during embryonic development and suggest a potential role for Math6 as a modulator of the differentiation program initiated by the pro-endocrine factor Neurog3. Furthermore, our results demonstrate that Math6 is indispensable for early embryonic development and indicate a more widespread function for this factor in tissue-specific differentiation processes that are dependent on class II bHLH genes
Universal Screening in Early Childhood Populations: A Systematic Review
Early childhood is an important period for the development of social, emotional and behavioral (SEB) skills. Deficits in these skills often lead to negative outcomes; thus, early identification is essential for the provision of services. Unfortunately, only a fraction of students with deficits are identified and receive services. One cause of this is the methods used to identify students, such as teacher nominations which do not identify all students in need (Dowdy et al., 2013). Proactive practices, such as universal screening, are a more systematic way of identification. The purpose of this review was to examine commonly used early childhood screeners and their evidence base, effectiveness, and the feasibility and accessibility of their use in early childhood settings. This critical review analysed 18 screeners using Southam-Gerow & Prinstein’s (2014) review criteria for evidence-based treatments and a technical adequacy rubric based on Glover and Albers’ (2007) considerations for evaluating universal screening assessments. Of the 18 screening tools reviewed, four screeners are highly recommended based on their technical adequacy and usability within early childhood settings. These results highlight the need for further research in the evaluation of early childhood universal screeners
Spherical collapse model in dark energy cosmologies
We study the spherical collapse model for several dark energy scenarios using
the fully nonlinear differential equation for the evolution of the density
contrast within homogeneous spherical overdensities derived from Newtonian
hydrodynamics. While mathematically equivalent to the more common approach
based on the differential equation for the radius of the perturbation, this
approach has substantial conceptual as well as numerical advantages. Among the
most important are that no singularities at early times appear, which avoids
numerical problems in particular in applications to cosmologies with dynamical
and early dark energy, and that the assumption of time-reversal symmetry can
easily be dropped where it is not strictly satisfied. We use this approach to
derive the two parameters characterising the spherical-collapse model, i.e.~the
linear density threshold for collapse and the virial
overdensity , for a broad variety of dark-energy models and
to reconsider these parameters in cosmologies with early dark energy. We find
that, independently of the model under investigation, and
are always very close to the values obtained for the
standard CDM model, arguing that the abundance of and the mean density
within non-linear structures are quite insensitive to the differences between
dark-energy cosmologies. Regarding early dark energy, we thus arrive at a
different conclusion than some earlier papers, including one from our group,
and we explain why.Comment: 11 pages, 7 figures, accepted for publications on MNRA
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