Endocrine disruptors (ED) are exogenous agents that interfere with the normal function of the endocrine system and they are considered environmental chemicals with estrogen-like and/or anti-androgenic activity with important impact on the reproductive axis. They act via nuclear receptors, non-nuclear steroid receptors, nonsteroidal receptors, orphan receptors, and different enzyme pathways involved in the biosynthesis and/or metabolism of steroids. The molecules identified as ED and sources of exposure are diverse and vary worldwide, including from natural chemicals found in human and animal food (the main source) up to synthetic chemicals, such as as solvents, plasticizers, pesticides, fungicides, pharmaceuticals etc. ED are incriminated in the occurrence of malignant tumors, birth defects, attention deficit disorders, cognitive impairment, brain development, deformations of the body (including limbs), disturbance of sexual development, menstrual irregularity, precocious puberty, feminizing or masculinizing effects, abortion, not least obesity and decreased fertility. The principles of action are still studied and controversial, therefore, it is difficult to determine the minimum level at which adverse effect occurs and further studies are required.

New developments in ultralow power electronic devices can now use much solution to energy harvesting systems designed to interface directly with a piezoelectric transducer. However, these environmental energy sources are typically very low power. Recently, a significant number of piezoelectric devices based on lead titanate zirconate (PZTN) have been designed with the purpose of the piezoelectric transducer. At INCDIE ICPE-CA Bucharest we have realized a piezoelectric transducer for which a PZT+Nb piezoelectric ceramic element was used for low energy source build with piezoelectric circular and linear transducers. Due to their dielectric proprieties and small size, (38 mm x 14 mm x 2 mm), the piezoelectric linear transducers can be optimize the energy harvesting systems applications for which the vibration duration is very short. A multiphysics numerical simulation further illustrates such piezoelectric transducer operation. The energy harvesting system is constituted of five functional blocks which are described in this paper.

In the present paper (1-x)Pb (Zr1-yTiy)O3 – xPb (Mn1/3Sb2/3)O3 – z at%E system, with E = Pr3+, Nd5+ and Gd3+ where x = 0.12; y = 0.48; z = 0 and 0.02 ceramic synthesized by solid state reaction technique is analysed. The investigation aims studying of the effect of dopants on the dielectric and piezoelectric properties of such piezoelectric ceramic. The prepared powders have been uniaxially pressed into discs with diameter of 10 – 12 mm and thickness of 1.2 mm. Sintering has been carried out in air atmosphere at temperatures of 1150°C and 1200°C, respectively, for 2 hours each, followed by a controlled cooling at a rate of 200°C /h. The piezoelectric properties have been investigated after a suitable preparation, including polishing, metallization. The structure of the samples has been determined by X-ray diffractometry (XRD), while the morphology and grains size have been investigated by the scanning electron microscopy (SEM). The piezoelectric properties have been studied by the resonance - antiresonance method. XRD analysis reveals a perovskite tetragonal structure and, as expected for ceramic materials, SEM analysis indicates that the average grain size increases as sintering temperature increases. The dielectric and piezoelectric properties have been determined measuring the ceramic discs, and properties, as dielectric permittivity (εr), dielectric loss (tg δ), and the electromechanical coupling factor (kp) have been obtained. The acquired results indicate a significant effect of the dopants on the dielectric and piezoelectric properties of such materials.

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Purpose: The purpose of this study was to determine the factors associated with the outcomes of selective laser trabeculoplasty (SLT). Patients and Methods: This was a database analysis (Lausanne Laser Trabeculoplasty Registry) of patients who had SLT between 2015 and 2017. Exclusion criteria were age below 40 years and diagnosis other than ocular hypertension and open-angle glaucoma. Intraocular pressure (IOP) and number of medications were recorded before and at various follow-ups after laser treatment. Success was defined as “complete” if an IOP reduction of at least 20% was observed at a given time, and “qualified” if any reduction of IOP was observed with either at least a 20% difference from baseline or a reduction in IOP-lowering medications. Associations of complete and qualified success with patients’ baseline characteristics, laser settings, and clinical examination findings were studied using multivariate regression and survival analysis. Results: A total of 170 eyes (126 patients) were included. Mean age was 68.3±12.2 years and 57.9% of the study cohort were female individuals. Average baseline IOP was 18.7±4.8 mm Hg, and average IOP reduction was 3.3±4.3 (−17.6% from baseline) and 3.5±3.9 mm Hg (−18.7% from baseline) at years 1 and 2, respectively. Male sex [odds ratio (OR)=2.79, P=0.02], baseline IOP (OR=1.15, P<0.01), and medical treatment before SLT (OR=2.57, P=0.03) were positive predictors of success. Total energy was associated with the duration of success. SLT outcome was strongly correlated to the outcome of the fellow eye, which represented the strongest predictor (OR=17.33, P<0.01). Conclusions: SLT achieved good IOP-lowering in a majority of patients with mild-to-moderate glaucoma, while it was inefficient in up to 35% of eyes. SLT success in the fellow eye was a strong predictive factor.