Dosimetric verification of the dynamic intensity-modulated radiation therapy of 92 patients

The initial period in the establishment of syringe exchange projects is often characterized by overt conflict: between community AIDS activists, on the one hand, and public officials and political leaders who remain ideologically opposed to the introduction of measures perceived as condoning illicit drug use. In this context, professionals concerned with legitimating the new institutions of syringe exchange may sometimes neglect aspects of their everyday logistics and social organization, obscuring the important choices which have to be made to carry these initiatives forward. In particular, the contrast between formally-constituted institutions-the "storefront" or "community-based" syringe exchange programs (SEPs)-and the model of low-threshold syringe availability through pharmacies, vending machines, and user networks, is here presented not as an either/or choice but rather as a pair of complementary strategies which respond to diverse needs and target different populations. The advantages and disadvantages of each particular approach make it likely that maximum effectiveness will be achieved through a combination of every possible form of needle distribution, each tailored to specific and cultural circumstances. The case is here examined in the light of the experience of the SEPs in New York City, from their clandestine origins in 1990 through their first years of official functioning in 1992-1996.     

Merging a DSP-Oriented Signal Integrity Technique and SW-Based Fault Handling Mechanisms to Ensure Reliable DSP Systems

Hereafter, we present an approach aiming to improve the reliability of digital signal processing (DSP) systems operating in real noisy (electromagnetic interference—EMI) environments. The approach is based on the coupling of two techniques: the DSP-oriented signal integrity improvement technique deals with increasing the signal-to-noise ratio (SNR) and is essentially a modification of the classic Recovery Blocks Scheme. The second technique, named SW-based fault handling aims to detect in real-time data- and control-flow faults throughout modifications of the processor code. When compared to conventional approaches using Fast Fourier Transform (FFT) and Hamming Code, the primary benefit of such an approach is to improve system reliability by means of a considerably low complexity, reasonably low performance degradation and, when implemented in hardware, with reduced area overhead. Aiming to illustrate the proposed approach, we implemented a HW/SW prototype to operate as a speech recognition system (SRS). This prototype was tested under a home-tailored EMI environment according to the IEC 61000-4-29 International Standard Normative. The obtained results indicate that the proposed approach can effectively improve the reliability of DSP systems operating in real noise (EMI) environments.     

Radiofrequency catheter ablation of an incessant supraventricular tachycardia initiated by a Hisian parasystole

The coexistence of a parasystolic focus, tachycardia dependent right bundle branch aberrancy, and an AV accessory pathway is reported here. This condition was present in a 40-year-old man, which led to an incessant AV reciprocating tachycardia. Further electrophysiological study revealed that the parasystolic focus was located somewhere in the His bundle; endocardial mapping disclosed a right posterior accessory pathway. Radiofrequency current was delivered at the atrial level of the right posterolateral AV groove and successfully ablated the accessory pathway, leading to a dramatic improvement in cardiac function. In conclusion, the recognition of the electrophysiological mechanism of incessant supraventricular tachycardia was of crucial importance for the therapy decision. A definitive intervention using radiofrequency catheter ablation should be considered early and not postponed in patients with tachycardia-induced cardiomyopathy.     

A simultaneous approach for compliance minimization and piezoelectric actuator design considering the polarization profile

This article addresses the compliance problem along with the piezoelectric actuator design for active vibration control. The topology structural design is obtained by solving a compliance minimization problem with volume constraint, whereas the actuator design is carried out by the maximization of a control performance index written in terms of the controllability Gramian. This measure describes the ability of the actuator to move the structure from an initial condition to a desired final state, at rest for instance, in a finite time interval. The actuator design is also characterized by the polarization profile, which is defined according to the distribution of an additional design variable. Therefore, the actuators can yield both tensile and compressing fields at different points of the structure using the same applied control voltage. To achieve this goal, a material interpolation scheme based on the solid isotropic material with penalization and the piezoelectric material with penalization and polarization (PEMAP-P) models is employed, and both the optimum structure/actuator layout and polarization profile are obtained simultaneously. The sensitivities with respect to the polarization and design variables are calculated analytically. Numerical examples are presented considering the design and vibration control for a cantilever beam, a beam fixed at both ends, and an L-bracket structure to show the efficiency of the proposed formulation. The control performance of the designed structures are analyzed employing a linear-quadratic regulator simulation, and these results are compared to verify the influence of the optimized polarization profiles.     

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.     

Study of particle packing of plywood,Eucalyptus spp. and Pinus spp. from construction and demolition waste

Wood from construction and demolition waste (CDW) can be incorporated into composites to produce new materials, contributing to the mitigation of environmental impacts. The objective of this work is to compare the particle size distribution (PSD) of wood particles of plywood, Eucalyptus spp. and Pinus spp., obtained by recycling CDW with the PSD curves proposed by particle packing models described in the literature. Three particle packing models were used for the comparison: the Fuller curve, the Andreasen model and the modified Andreasen model. All three models should represent an ideal PSD used as goal to be achieved. The packing density of these PSD curves was calculated using the Compressible Packing Model (CPM) and measured experimentally. When comparing the experimental PSD of the wood particles to the PSD from the packing models, the results demonstrated that they do not fit exactly. This was expected and since wood particles present unique morphology characteristics, it is possible that an ideal PSD curve used for concrete (packing density models used were originally proposed for the use in concrete technology field) is different from an ideal PSD to be used for wood composites. Thus, packing density determination is needed. The PSD curve from the modified Andreasen model provided higher experimental packing density regardless of wood types. Using particle packing models based on ideal PSD increased the packing density by 19.3% on average, compared with experimental packing density of the individual classes for each wood particle size. This represents savings in the consumption of binder paste when producing mineral composites containing these wood particles using the studied PSD curves.

     

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....     

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