Perceptually-Motivated Coded Apertures

Computational perception techniques are gaining increasing importance in all different steps of the imaging pipeline, from data capture to final display. The goal of these techniques is usually the same: to minimize visible errors in the final image. We present a method to compute coded apertures for defocus deblurring that takes into account human perception to obtain the optimal aperture pattern. We pose the problem of finding the optimal aperture as an optimization, and -to our knowledge- propose the first algorithm that makes use of perceptual quality metrics in its objective function. We explore the performance of different quality metrics for the design of such coded apertures, including the well-established SSIM, the state-of-the-art HDR-VDP-2, which features a comprehensive model of the HVS, as well as the L2 norm, previously used in related works.Our results outperform both conventional circular apertures and a previously published aperture pattern specifically designed for defocus deblurring [1], both in simulated and real scenarios (see Figures 1 and 2). The best apertures are obtained when a combination of the three metrics is used in the objective function. This work has been recently accepted for publication at the Computer Graphics Forum [2]

Decreased parenchymal arteriolar tone uncouples vessel-to-neuronal communication in a mouse model of vascular cognitive impairment

Chronic hypoperfusion is a key contributor to cognitive decline and neurodegenerative conditions, but the cellular mechanisms remain ill-defined. Using a multidisciplinary approach, we sought to elucidate chronic hypoperfusion-evoked functional changes at the neurovascular unit. We used bilateral common carotid artery stenosis (BCAS), a well-established model of vascular cognitive impairment, combined with an ex vivo preparation that allows pressurization of parenchymal arterioles in a brain slice. Our results demonstrate that mild (~ 30%), chronic hypoperfusion significantly altered the functional integrity of the cortical neurovascular unit. Although pial cerebral perfusion recovered over time, parenchymal arterioles progressively lost tone, exhibiting significant reductions by day 28 post-surgery. We provide supportive evidence for reduced adenosine 1 receptor-mediated vasoconstriction as a potential mechanism in the adaptive response underlying the reduced baseline tone in parenchymal arterioles. In addition, we show that in response to the neuromodulator adenosine, the action potential frequency of cortical pyramidal neurons was significantly reduced in all groups. However, a significant decrease in adenosine-induced hyperpolarization was observed in BCAS 14 days. At the microvascular level, constriction-induced inhibition of pyramidal neurons was significantly compromised in BCAS mice. Collectively, these results suggest that BCAS uncouples vessel-to-neuron communication—vasculo-neuronal coupling—a potential early event in cognitive decline.Fil: Kim, Ki Jung. Augusta University. Departament of Physiology; Estados UnidosFil: Diaz, Juan Ramiro. Augusta University. Departament of Physiology; Estados UnidosFil: Presa, Jessica Lorena. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Augusta University. Departament of Physiology; Estados UnidosFil: Muller, P. Robinson. Augusta University. Departament of Physiology; Estados UnidosFil: Brands, Michael W.. Augusta University. Departament of Physiology; Estados UnidosFil: Khan, Mohammad B.. Augusta University. Medical College of Georgia; Estados UnidosFil: Hess, David C.. Augusta University. Medical College of Georgia; Estados UnidosFil: Althammer, Ferdinand. Georgia State University; Estados UnidosFil: Stern, Javier E.. Georgia State University; Estados UnidosFil: Filosa, Jessica A.. Augusta University. Departament of Physiology; Estados Unido

Trends and extremes of drought episodes in Vietnam sub-regions during 1980–2017 at different timescales

This study investigated the temporal occurrence of dry conditions in the seven climatic sub-regions of Vietnam during the 1980–2017 period. This assessment was performed using the Standardized Precipitation Evapotranspiration Index (SPEI) and the Standardized Precipitation Index (SPI) at 1 to 24 months timescales. Results show that the main periods of extreme drought occurred simultaneously throughout the country in 1992–1993 and 2003–2004, except for 2015–2016, when it was not identified in the southern region. In addition, a slight temporal lag was identified latitudinally (north–south) at the beginning of dry conditions, revealing the largest difference between the northern and southern regions. A positive trend in the time series of both indices (SPEI and SPI) prevailed in all sub-regions, with the SPEI minus SPI difference always being negative, suggesting the importance of temperature and evapotranspiration for this trend. Further detailed analyses were then performed using SPEI at 1-month and 12-months timescales for all climate sub-regions, as well as the main indicators to characterize duration and severity. Results show that the number of drought episodes did not vary much between regions, but they did vary in duration and severity at the annual scale. Moreover, changes in the soil root zone are largely associated with dry and wet conditions not only from season to season, but also in longer accumulation periods and more strongly in the northern regions of Vietnam. Indeed, a study of the most severe drought episodes also revealed the occurrence of negative anomalies of the root-soil moisture in the subsequent four or more months. Dynamic atmospheric conditions associated with the peak of most severe drought episodes show the crucial role of subsidence of dry air in the middle and high atmosphere, which prevents convection in the lower troposphere. Finally, the linkages between drought conditions in Vietnam and large-scale atmospheric and oceanic teleconnection patterns were revealed to be quite different among northern and southern sub-regions. During the positive phase of El Niño–Southern Oscillation (ENSO), drought episodes at different timescales were identified in the southern climate sub-regions, while the negative phase was associated with drought conditions in the northern regions.Xunta de Galicia | Ref. ED481B 2019/070Fundação para a Ciência e a Tecnología | Ref. UIDB/50019/2020–IDLXunta de Galicia | Ref. ED481B 2018/062Xunta de Galicia | Ref. ED431C 2017/64-GRCMinisterio de Ciencia, Innovación y Universidades | Ref. RTI2018-095772-B-I00Fundação para a Ciência e a Tecnología | Ref. PTDC/CTA-MET/29233/201

Functionalization of La0.33Ca0.67MnO3 with biologically active small ligand at room temperature

Wereportthestructural,morphological andopticalactivities of a paramagneticmanganite(La0.33Ca0.67MnO3) synthesized at 900�C. A simple method of formation of complex was employed. A complex was formed between a pre-prepared manganite dissolved in HCl and reacted with an organic ligand (ethyl 4-nitrobenzoate). The optical and antimicrobial properties of a complex were determined. The Ultraviolet-visible and Fourier-transforminfra-red spectroscopy wereused inmonitoringoptical activitiesof theresultingproduct. Itwasobserved toabsorb in thevisible region (205nmand256nm). The peaks observed from the infra-red spectra indicated that the reaction occurred at the nitroso end of the ethyl 4- nitrobenzoate. The bacterial inhibitorypropertyoftheLCMO-ethyl 4-nitrobenzoatewasdetermined against Pseudomonas aeruginosa, Candida albican, Aspergillus niger and Staphylococcus auerus. It was observed to inhibit the growth of all the microbes with zone of inhibitions of 60mm, 56mm, 45mm and 32mm, for Pseudomonas aeruginosa, Candida albican, Aspergillus niger and Staphylococcus auerus, respectivel

Increased circulating ANG II and TNF-α represents important risk factors in obese Saudi adults with hypertension irrespective of diabetic status and BMI

Central adiposity is a significant determinant of obesity-related hypertension risk, which may arise due to the pathogenic inflammatory nature of the abdominal fat depot. However, the influence of pro-inflammatory adipokines on blood pressure in the obese hypertensive phenotype has not been well established in Saudi subjects. As such, our study investigated whether inflammatory factors may represent useful biomarkers to delineate hypertension risk in a Saudi cohort with and without hypertension and/or diabetes mellitus type 2 (DMT2). Subjects were subdivided into four groups: healthy lean controls (age: 47.9±5.1 yr; BMI: 22.9±2.1 Kg/m2), non-hypertensive obese (age: 46.1±5.0 yr; BMI: 33.7±4.2 Kg/m2), hypertensive obese (age: 48.6±6.1 yr; BMI: 36.5±7.7 Kg/m2) and hypertensive obese with DMT2 (age: 50.8±6.0 yr; BMI: 35.3±6.7 Kg/m2). Anthropometric data were collected from all subjects and fasting blood samples were utilized for biochemical analysis. Serum angiotensin II (ANG II) levels were elevated in hypertensive obese (p<0.05) and hypertensive obese with DMT2 (p<0.001) compared with normotensive controls. Systolic blood pressure was positively associated with BMI (p<0.001), glucose (p<0.001), insulin (p<0.05), HOMA-IR (p<0.001), leptin (p<0.01), TNF-α (p<0.001) and ANG II (p<0.05). Associations between ANG II and TNF-α with systolic blood pressure remained significant after controlling for BMI. Additionally CRP (p<0.05), leptin (p<0.001) and leptin/adiponectin ratio (p<0.001) were also significantly associated with the hypertension phenotype. In conclusion our data suggests that circulating pro-inflammatory adipokines, particularly ANG II and, TNF-α, represent important factors associated with a hypertension phenotype and may directly contribute to predicting and exacerbating hypertension risk

Positive psychology of Malaysian students: impacts of engagement, motivation, self-compassion and wellbeing on mental health

Malaysia plays a key role in education of the Asia Pacific, expanding its scholarly output rapidly. However, mental health of Malaysian students is challenging, and their help-seeking is low because of stigma. This study explored the relationships between mental health and positive psychological constructs (academic engagement, motivation, self-compassion, and wellbeing), and evaluated the relative contribution of each positive psychological construct to mental health in Malaysian students. An opportunity sample of 153 students completed the measures regarding these constructs. Correlation, regression, and mediation analyses were conducted. Engagement, amotivation, self-compassion, and wellbeing were associated with, and predicted large variance in mental health. Self-compassion was the strongest independent predictor of mental health among all the positive psychological constructs. Findings can imply the strong links between mental health and positive psychology, especially selfcompassion. Moreover, intervention studies to examine the effects of self-compassion training on mental health of Malaysian students appear to be warranted.N/

Corrosion inhibitory properties of La0.5Ca0.5MnO3-gold nanoparticles in 1 M HCl

The morphological, magnetic, transport and corrosion inhibitory property of La0.5Ca0.5MnO3-AuNPs prepared by sol gel method was determined. The structural property determined by XRD indicated that the unusual broadening of the Bragg’s reflection despite the elevated sintering temperature was as a result of the inhibition of the grain growth by the gold nanoparticles (Au-NPs). The morphological property of the sample as determined by SEM and TEM show heterogeneously sized and shaped nanoparticles of an average particle size of 40 nm. The magnetic measurements of La0.5Ca0.5MnO3-AuNPs showed that the sample undergoes a paramagnetic – ferromagnetic phase transition with TC = 250K and TB = 150K. Two metalinsulator transitions were observed at T1 and T2. The resistivity of the sample was observed to reduce as temperature increased to 300 K. The gravimetric method was used to determine the corrosion inhibitory properties with 1.0 M HCl using different concentration of La05Ca0.5MnO3- AuNPs. The anti-corrosion study was carried out for 21 days and was observed to reduce as concentration of La0.5Ca0.5MnO3-AuNPs increased, but corrosion rate increased as the exposure time increased. The inhibitory property of the sample increased as the concentration of the sample increased. The reaction best fitted the Langmuir isotherm, indicating a monolayer of La0.5Ca0.5MnO3-AuNPs inhibiting the corrosion of the mild steel

Particle interactions in liquid magnetic colloids by zero field cooled measurements: effects on heating efficiency

The influence of magnetic interactions in assemblies formed by either aggregated or disaggregated uniform gamma-Fe_2O_3 particles are investigated as a function of particle size, concentration, and applied field. Hyperthermia and magnetization measurements are performed in the liquid phase of colloids consisting of 8 and 13 nm uniform gamma-Fe_2O_3 particles dispersed in water and hexane. Although hexane allows the disagglomerated obtaining particle system; aggregation is observed in the case of water colloids. The zero field cooled (ZFC) curves show a discontinuity in the magnetization values associated with the melting points of water and hexane. Additionally, for 13 nm gamma-Fe_2O_3 dispersed in hexane, a second magnetization jump is observed that depends on particle concentration and shifts toward lower temperature by increasing applied field. This second jump is related to the strength of the magnetic interactions as it is only present in disagglomerated particle systems with the largest size, i.e., is not observed for 8 nm superparamagnetic particles, and surface effects can be discarded. The specific absorption rate (SAR) decreases with increasing concentration only for the hexane colloid, whereas for aqueous colloids, the SAR is almost independent of particle concentration. Our results suggest that, as a consequence of the magnetic interactions, the dipolar field acting on large particles increases with concentration, leading to a decrease of the SAR