Interval regression model adequacy checking and its application to estimate school dropout in Brazilian municipality educational scenario

Pattern Analysis and Applications - Interval-valued data have been commonly encountered in practice, and Symbolic Data Analysis provides a solution to the statistical treatment of these data....     

Preconceptional Immunization Can Modulate Offspring Intrathymic IL-17-Producing γδT Cells with Epigenetic Implications Mediated by microRNAs

The mechanisms through which maternal immunization can modulate offspring thymic maturation of lymphocytes are not fully understood. Here, we aimed to evaluate whether maternal OVA-immunization can inhibit the maturation of IL-17-producing γδT cells in offspring thymus, and if this mechanism has epigenetic implications mediated by microRNAs (miRNAs) expression. Wild-type (WT) C57BL/6 females were immunized with OVA in Alum or Alum alone and were mated with normal WT males. Evaluating their offspring thymus at 3 or 20 days old (d.o.), we observed that maternal OVA immunization could inhibit the thymic frequency of offspring CD27- and IL-17⁺ γδT cells at the neonatal and until 20 days old. Furthermore, we evaluated the expression of function-related γ and δ variable γδTCR chains (Vγ1, Vγ2, Vγ3, Vδ4, and Vδ6.3), observing that maternal OVA-immunization inhibits Vγ2 chains expression. The small RNAs (sRNAs), particularly miRNAs, and messenger RNAs (mRNA) expression profiles by pools of thymus tissue samples (from 9 to 11 mice) from offspring OVA-immunized or Alum-immunized mothers were analyzed via Illumina sequencing platform and bioinformatics approaches. Using a fold change >4, our results showed that seven miRNAs (mmu-miR-126a-3p, 101a-3p, 744-3p,142-5p, 15a-5p, 532-5p, and 98-5p) were differentially expressed between both groups. Ten target genes were predicted to interact with the seven selected miRNAs. There were no enriched categories of gene ontology functional annotation and pathway enrichment analysis for the target genes. Interestingly, four of the identified miRNAs (mmu-miR-15a, mmu-miR-101 mmu-miR-126, and mmu-miR-142) are related to IL-17 production. Our data is of significance because we demonstrate that maternal immunization can modulate offspring thymic maturation of IL-17-producing γδT cells possibly by an epigenetic mechanism mediated by miRNAs.     

A novel bioactive agent improves adhesion of resin-modified glass-ionomer to dentin

Bioactive glasses are surface-active and able to induce remineralization of dentin. Two resin-modified glass-ionomer cements (RMGICs) doped with bioactive glass (Biosilicate^®) were used as restorative materials in dentin. Experimental powders were made by incorporating 2, 5, and 10 wt% of Biosilicate^® in Vitremer^® (VT) and Fuji II LC^® (FL) powders. Commercial FL and VT were used as control materials. Six cylinders of each material were tested for failure in compression (1.0 mm/min), after 24 h storage in distilled water at 37 °C. For microtensile bond strength (MTBS) test, cavity preparations were performed on 30 noncarious human molars and restored with the tested materials. Teeth were stored in water (37 °C) for 24 h or 7 days, sectioned into beams and tested for failure in tension (0.5 mm/min). Data were analyzed by analysis of variance and multiple-comparison tests (p < 0.05). Analysis of debonded specimens was performed by scanning electron microscopy. Only incorporation of 2 wt% of Biosilicate^® did not decrease compressive strength of the RMGICs. Two weight percent of Biosilicate^® into RMGICs produced an increase in MTBS after 24 h for FL and after 24 h and 7 days for VT. Two weight percent of Biosilicate^® particles into RMGICs did not affect compressive strength and improved MTBS to dentin.     

Influence of a crosslinked system on the morphology and properties of TPVs based on PA/NBR

The mechanical properties of thermoplastic vulcanizates (TPVs), depend strongly on their morphologies, which themselves depend on the properties of the primary polymers, the composition of the TPV, and the crosslink system and crosslink process. The morphology is defined during the dynamic vulcanization. This work deals with the study of the influence of crosslink systems on TPVs based on PA/NBR (copolyamide PA6/6‐6 and nitrile rubber) in a 40/60 composition. Dicumyl peroxide, bismaleimide, phenolic resin, a sulfur‐accelerated system, and dicumyl peroxide with two coagents were used as crosslinkers. TPVs were characterized by taking into account their mechanical strength, solvent resistance, compression set, and morphology. The curing system constituted by dicumyl peroxide and sulfur/bismaleimide as coagents resulted in a more defined morphology, and therefore the TPV exhibited the best properties. For these TPVs, a morphology consisting of spherical domains of rubber distributed homogeneously on the polyamide matrix could be observed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Bioactive Compounds and Stability of Organic and Conventional Vitis labrusca Grape Seed Oils

The aim of this study was to determine the differences between organic and conventional grape seed oils extracted from different grapes (Bordô and Isabel). The physicochemical quality, bioactive compounds and oxidative stability of the oils were investigated. The organic samples exhibited the best color parameters, and all samples were within the limits established by the Codex Alimentarius regarding their quality parameters. Only Bordô grape seed oils presented lutein and the best results regarding α‐ and β‐carotene and α‐tocopherol contents. All samples exhibited the same antioxidant activity results, but the Bordô ones exhibited higher oxidative stability. Overall, the results from this study suggest no differences between organic and conventional grape seed oils but between the grape varieties.     

Pharmacological Proprieties of the Ethanol Extract of Muehlenbeckia platyclada (F. Muell.) Meisn. Leaves

Antinociceptive and anti-inflammatory activities of the Muehlenbeckia platyclada leaves' ethanol extract were investigated in animal models. The extract (p.o.) reduced the number of abdominal contortions induced by acetic acid by 21.57% (400 mg/kg). After intraplantar injection of formalin, a dose of 400 mg/kg (p.o.) inhibited the time spent paw licking in the first phase (26.43%), while the second phase was inhibited by 10.90 and 36.65% at the doses of 200 and 400 mg/kg, respectively. The extract (p.o.) increased the reaction time on a hot plate at a dose of 400 mg/kg (32.68 and 40.30%) after 60 and 90 minutes of treatment, respectively. The paw edema was reduced by extract (p.o.) at doses of 100 (15.46 and 16.67%), 200 (22.68 and 25.64%) and 400 mg/kg (29.50 and 37.33%) after 3 to 4 h of carrageenan application, respectively. Doses of 100, 200 and 400 mg/kg (p.o.), administered 4 h after the carrageenan injection, reduced the exudate volume (11.28, 21.54 and 45.13%), while leukocyte migration was reduced by 21.21 and 29.70% at the doses of 200 and 400 mg/kg, respectively. These results indicate that the ethanol extract from M. platyclada may constitute a potential target for the discovery of new molecules with antinociceptive and anti-inflammatory activities that can be explored for their therapeutic use.     

Metal strip reflectivity and NSPUDT orientations in langanite,langasite, and gallium phosphate

New materials of the trigonal 32 class have received much attention recently, due to their quartz-like temperature behavior and the promise of higher electromechanical coupling coefficients. The magnitude and phase of the reflection coefficient of the metal strips that form the SAW transducers and reflector structures is a critical parameter that allows proper device designs and optimal material surface orientation. This paper describes an investigation of the magnitude and phase of the SAW metal strip reflectivity in some new materials and along now orientations. The materials are langanite, langasite, and gallium phosphate. The results are presented as contour plots of the magnitude and phase of the reflection coefficient. In addition, the phase velocity, temperature coefficient of delay, electromechanical coupling coefficient, and power flow angle are given, thus allowing proper orientation selection for SAW device designs. The results presented highlight the reflection coefficient calculations in the selection of natural single-phase unidirectional transducer orientations (NSPUDT) for these new materials. The orientation regions suggested in this paper for the new materials are thus very promising for low-loss, high-performance consumer and communications SAW designs, such as NSPUDT filters, resonator-based filters, and other devices that can benefit from a high metal strip reflectivity     

An On-Chip Sensor to Monitor NBTI Effects in SRAMs

The increasing need to store more and more information has resulted in the fact that Static Random Access Memories (SRAMs) occupy the greatest part of Systems-on-Chip (SoCs). Therefore, SRAM’s robustness is considered crucial in order to guarantee the reliability of such SoCs over lifetime. In this context, one of the most important phenomena that degrades Nano-Scale SRAMs reliability is related to Negative-Bias Temperature Instability (NBTI), which causes the memory cells aging. The main goal of this paper is to present a hardware-based approach able to monitor SRAMs’ aging during the SoC’s lifetime based on the insertion of On-Chip Aging Sensors (OCASs). In more detail, the proposed strategy is based on the connection of one OCAS to every SRAM column, each periodically monitoring write operations on the SRAM cells. It is important to note that in order to prevent the OCAS from aging and to reduce leakage power dissipation, the OCAS circuitry is powered-off during its idle periods. The proposed hardware-based approach has been evaluated throughout SPICE simulations using 65 nm CMOS technology and the results demonstrate the sensor’s capacity to detect early aging states and therefore, guaranteeing high SRAM reliability. To conclude, a complete analysis of the sensor’s overheads is presented.     

Investigation on recent quartz-like materials for SAW applications

Recent progress in growing and characterizing quartz-like materials of the trigonal system class 32 has been reported by several groups. The promising perspective for bulk acoustic wave frequency control applications indicates the potentiality of employing these materials for SAW applications as well. This paper reports results of investigations focused on SAW orientations of langasite (LGS), gallium phosphate (GaPO(4)), and langanite (LGN), both singly and doubly rotated cuts. Among the characteristics explored, major attention is paid to the temperature coefficient of delay (TCD), the electromechanical coupling coefficient (K(2)), and the power flow angle (PFA). Contour graphs are plotted based on our calculated results and show the regions in space in which low TCD and high K(2 ) can be obtained; they also exhibit the associated PFA and phase velocity characteristics. The influence of different sets of material constants is addressed. The spatial investigation performed shows that there are promising orientation regions in these materials at which zero or reduced TCD (<10 ppm/ degrees C) and PFA are obtained. Additional attractive characteristics for SAW applications have been observed: values of K(2) a few times higher than the K(2) of quartz ST-X, thus finding applications in larger bandwidth devices; variation of the TCD with respect to temperature, which is comparable to the variation found for quartz ST-X and less than that for zero TCD Li (2)B(4)O(7) cuts like 45 degrees X-Z and (0 degrees 78 degrees 90 degrees ); and phase velocity values circa 13 to 26% smaller than the phase velocity of quartz ST-X thus allowing a reduction in size for intermediate frequency device applications.