Γ To Xz Electron Transfer Times In Type-ii Superlattices Due To Emission Of Confined Phonons

We calculate the Γ→Xz electron transfer times due to the emission of confined longitudinal optical phonons in type-II GaAs-AlAs and AlGaAs-AlAs superlattices. A dielectric continuum model is employed to describe the electron-confined-phonon interaction and the electron envelope wave functions are obtained from a Kronig-Penney model. The calculated transfer times compare within order of magnitude, or better, with available experimental results and we obtain a good qualitative description of the transfer time dependence on the layer thicknesses.65101281128

Investigating the impact of combining handwritten signature and keyboard keystroke dynamics for gender prediction

© 2019 IEEE. The use of soft-biometric data as an auxiliary tool on user identification is already well known. Gender, handorientation and emotional state are some examples which can be called soft-biometrics. These soft-biometric data can be predicted directly from the biometric templates. It is very common to find researches using physiological modalities for soft-biometric prediction, but behavioural biometric is often not well explored for this context. Among the behavioural biometric modalities, keystroke dynamics and handwriting signature have been widely explored for user identification, including some soft-biometric predictions. However, in these modalities, the soft-biometric prediction is usually done in an individual way. In order to fill this space, this study aims to investigate whether the combination of those two biometric modalities can impact the performance of a soft-biometric data, gender prediction. The main aim is to assess the impact of combining data from two different biometric sources in gender prediction. Our findings indicated gains in terms of performance for gender prediction when combining these two biometric modalities, when compared to the individual ones

Effects of foliar versus soil water application on ecophysiology, leaf anatomy and growth of pineapple

In the subtropics, pineapple [Ananas comosus (L.) Merr.] can be grown in plastic greenhouses to avoid low temperature, which is the main limiting factor to production outside of the tropics. Foliar water application and subsequent evaporative cooling can help avoid excessive leaf temperatures in greenhouses during the hot seasons. The effects of foliar versus soil irrigation on ecophysiology, leaf anatomy and leaf temperature of pineapple in protected culture were tested to determine if the crop could receive sufficient irrigation to avoid plant stress solely from misting the foliage. Materials and methods - Relative water content, relative chlorophyll content, normalized difference vegetation index, membrane stability, and cross sectional leaf anatomy were measured at periodic intervals. Pineapple plants were subjected to soil irrigation, misting and drought. At the beginning and at the end of the experiment, total leaf area, plant biomass and assimilate partitioning to leaves, stems and roots were measured. Results and discussion - The normalized difference vegetation index revealed differences among treatments after fifteen days without irrigation. Pineapple plants endured thirty days of water stress without membrane damage. Plants irrigated by applying water only to the leaves did not receive adequate water amounts and showed similar signs of drought stress as those of the non-irrigated treatment. Conclusion - Based on ecophysiological, anatomical and growth responses, soil water application alone is sufficient for avoiding water stress and excessively high leaf temperatures of pineapple plants grown in protected culture in the subtropics, whereas only misting the leaves does not provide adequate water supply to prevent water stress.Fil: Demarco, Paula. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Departamento de Produccion Vegetal.; ArgentinaFil: Gómez Herrera, Melanie Desirée. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Química Básica y Aplicada del Nordeste Argentino. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas Naturales y Agrimensura. Instituto de Química Básica y Aplicada del Nordeste Argentino; ArgentinaFil: Gonzalez, A.M.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Alayón Luaces, Paula. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Departamento de Produccion Vegetal.; Argentin

Comparing ray-theoretical and finite-frequency teleseismic traveltimes:Implications for constraining the ratio of S-wave to P-wave velocity variations in the lower mantle

A number of seismological studies have indicated that the ratio R of S-wave and P-wave velocity perturbations increases to 3–4 in the lower mantle with the highest values in the large low-velocity provinces (LLVPs) beneath Africa and the central Pacific. Traveltime constraints on R are based primarily on ray-theoretical modelling of delay times of P waves (ΔTP) and S waves (ΔTS), even for measurements derived from long-period waveforms and core-diffracted waves for which ray theory (RT) is deemed inaccurate. Along with a published set of traveltime delays, we compare predicted values of ΔTP, ΔTS, and the ΔTS/ΔTP ratio for RT and finite-frequency (FF) theory to determine the resolvability of R in the lower mantle. We determine the FF predictions of ΔTP and ΔTS using cross-correlation methods applied to spectral-element method waveforms, analogous to the analysis of recorded waveforms, and by integration using FF sensitivity kernels. Our calculations indicate that RT and FF predict a similar variation of the ΔTS/ΔTP ratio when R increases linearly with depth in the mantle. However, variations of R in relatively thin layers ( 20 s). This is because FF predicts that ΔTP and ΔTS vary smoothly with epicentral distance even when vertical P-wave and S-wave gradients change abruptly. Our waveform simulations also show that the estimate of R for the Pacific LLVP is strongly affected by velocity structure shallower in the mantle. If R increases with depth in the mantle, which appears to be a robust inference, the acceleration of P waves in the lithosphere beneath eastern North America and the high-velocity Farallon anomaly negates the P-wave deceleration in the LLVP. This results in a ΔTP of about 0, whereas ΔTS is positive. Consequently, the recorded high ΔTS/ΔTP for events in the southwest Pacific and stations in North America may be misinterpreted as an anomalously high R for the Pacific LLVP

Body image association and habitual physical activity in institutionalized elderly

Research clearly shows that physical activity (PA) is one important factor in developing and maintaining good health and function in older people. Knowledge of the underlying processes that influence the elderly to initiate and maintain lifestyle changes is an important requirement for the development of a PA intervention. The aim of this study is to analyse the variation of the body image at its component parts of perception and satisfaction and the ha- bitual PA in institutionalized old people of both genders who are physically active or not. Methods: The sample (n=33; 77,6 ± 5,75, years) was divided into two different groups, the Physical Active Group (PAG, n =18) and the Physical Inactive Group (PIG, n = 15). The PAG comprises 10 fe- males and 8 males and PIG comprises 6 females and 9 males. The perception of the body image was assessed by the Body Size Estimation Method; the satisfaction with the body image was assessed by the Body Image Satisfaction Questionnaire. The questionnaire Physical Activity Scale for the Elderly (PASE) was used to evaluate the habitual PA. We adopted the following statistical procedures: Descrip- tive Statistics (mean, standard deviation and frequency dis- tribution) and Inferential Statistic (nonparametric tests for independent samples, Mann Whitney U and Chi- Square test). Results: The following results have shown that in average, no statistics significance was found between the mean of satisfaction with the body image, when comparing genders and the physically active elderly and the physically inactive elderly. Conclusion: The main conclusions are:(i) the perceptions of the body image do not differ between old people, neither in gender nor in PA; (ii) the satisfaction with the body image does not differ in gender neither in PA; (iii) the habitual PA does not differ in gender.info:eu-repo/semantics/publishedVersio

High intensity tapping regime in a frustrated lattice gas model of granular compaction

In the frame of a well established lattice gas model for granular compaction, we investigate the high intensity tapping regime where a pile expands significantly during external excitation. We find that this model shows the same general trends as more sophisticated models based on molecular dynamic type simulations. In particular, a minimum in packing fraction as a function of tapping strength is observed in the reversible branch of an annealed tapping protocol.Comment: 5 pages, 4 figure

Metabolomic analysis of the toxicity pathways elicited by subtoxic concentrations of methylone in primary mouse hepatocytes

info:eu-repo/semantics/publishedVersio

Classification of the pre-exam anxiety levels in physically inactive students from 48 countries: application of the K-means clustering machine learning algorithm.

Physical inactivity is a behavioral factor that is strongly associated with anxiety symptoms in children and adolescents. Anxiety is a disabling condition that reduces academic performance (Kandola et al., 2020).info:eu-repo/semantics/publishedVersio

Accessing gelling ability of vegetable proteins using rheological and fluorescence techniques

This work aims to present a comprehensive study about the macroscopic characteristics of globular vegetable proteins, in terms of their gelling ability, by understanding their molecular behaviour, when submitted to a thermal gelling process. The gels of soy, pea and lupin proteins were characterized by rheological techniques. Gelation kinetics, mechanical spectra, as well as the texture of these gels were analyzed and compared. Additionally, capillary viscometry, steady-state fluorescence and fluorescence anisotropy were used to monitor the structural changes induced by the thermal denaturation, which constitutes the main condition for the formation of a gel structure. Based on these techniques it was possible to establish a relationship between the gelling ability of each protein isolate and their structural resistance to thermal unfolding, enabling us to explain the weakest and the strongest gelling ability observed for lupin and soy proteins isolates, respectivel

Immunogenetic features of steroid-sensitive nephrotic syndrome and focal segmental glomeru losclerosis in Brazilian patients of the northeast region of the state of São Paulo

A síndrome nefrótica corticossensível (SNCS) e a glomerulonefrite esclerosante segmentar e focal (GESF) compartilham características imunológicas e patogênicas. Foram estudados 93 pacientes brasileiros (46 com SNCS e 47 com GESF) e 104 indivíduos-controle, para caracterizar os perfis imunogenéticos dessas variedades de síndromes nefróticas idiopáticas. Os antígenos HLA-A, -B e –DR foram tipificados, usando-se método sorológico. Embora nenhuma associação com os antígenos HLA-A ou –B fosse observada, as freqüências dos antígenos HLAB7 e –B12 estavam significantemente elevadas nos pacientes com SNCS. Os antígenos HLADR7, HLA-DR1 e a combinação de antígenos HLA-DR1/DR7 estavam significantemente elevados nos pacientes com SNCS, em relação aos indivíduos-controle, ou em relação aos pacientes com GESF. A avaliação somente de pacientes caucasóides revelou que o antígeno HLA-DR7 continuava elevado nos pacientes com SNCS. O haplótipo HLA-B7/DR7 estava significantemente elevado nos pacientes com SNCS e GESF. Embora a população brasileira seja altamente miscigenada, a freqüência do antígeno HLA-DR7, que confere susceptibilidade a SNCS em outras populações, estava também elevada na série de pacientes caucasóides aqui estudada.Steroid-sensitive nephrotic syndrome (SSNS) and focal segmental glomerulosclerosis (FSGC) share immunologic and pathogenetic features. We studied 93 Brazilian patients (46 with SSNS and 47 with FSGC) and 104 control subjects with the objective of characterizing the immunogenetic profile of these varieties of idiopathic nephrotic syndrome. HLA-A, -B, and -DR antigens were typed using a complement-dependent microlymphocytotoxicity assay. No significanty association was observed with HLA-A or -B antigens in either group; however, HLA-B7 and -B12 antigens were increased in SSNS patients. HLA-DR7, -DR1 and the combination of HLA-DR1/DR7 antigens were significantly increased in the total group of patients with SSNS compared to controls or to FGSC patients. The study of only Caucasoid individuals revealed that HLA-DR7 antigen remained significantly increased in SSNS patients. The HLA-B7/DR7 haplotype was siginificantly increased in both SSNS and FSGC patients. Although the Brazilian population is highly miscigenated, the same antigen (HLA-DR7) which confers susceptibility to SSNS in other Caucasian population is still prevalent in this series