An Efficient Green Synthesis of 3-Amino-1H-chromenes Catalyzed by ZnO Nanoparticles Thin-film

A very simple and environmentally benign approach for the synthesis of 3-amino-1H-chromenes is described using ZnO nanoparticles thin-film as an efficient heterogeneous catalyst in green media, namely water. The mild reaction conditions, reusability of the catalyst, easy work-up and high yields of products make the present protocol sustainable and advantageous compared to conventional methods.KEYWORDS:  3-Amino-1H-chromene, aqueousmedium,hydrothermalsolution method, reusability of the catalyst,ZnOnanoparticles thin-film

A simple analytical method for heterogeneity corrections in low dose rate prostate brachytherapy

In low energy brachytherapy, the presence of tissue heterogeneities contributes significantly to the discrepancies observed between treatment plan and delivered dose. In this work, we present a simplified analytical dose calculation algorithm for heterogeneous tissue. We compare it with Monte Carlo computations and assess its suitability for integration in clinical treatment planning systems. The algorithm, named as RayStretch, is based on the classic equivalent path length method and TG-43 reference data. Analytical and Monte Carlo dose calculations using Penelope2008 are compared for a benchmark case: a prostate patient with calcifications. The results show a remarkable agreement between simulation and algorithm, the latter having, in addition, a high calculation speed. The proposed analytical model is compatible with clinical real-time treatment planning systems based on TG-43 consensus datasets for improving dose calculation and treatment quality in heterogeneous tissue. Moreover, the algorithm is applicable for any type of heterogeneities

Excitatory amino acidergic pathways and receptors in the basal ganglia

The striatum receives the majority of excitatory amino acidergic input to the basal ganglia from neocortical and allocortical sources. The subthalamic nucleus and the substantia nigra also receive excitatory amino acidergic inputs from neocortex. The subthalamic nucleus, which has prominent projections to the pallidum and nigra, is the only known intrinsic excitatory amino acidergic component of the basal ganglia. Possible excitatory amino acidergic inputs reach the basal ganglia from the intralaminar thalamic nuclei and the pedunculo-pontine nucleus. The striatum is richly endowed with all subtypes of excitatory amino acid receptors and these appear to be inhomogeneously distributed within the striatal complex. The non-striatal nuclei contain lesser levels of excitatory amino acid receptors and the relative proportion of these receptors varies between nuclei. The presence of high densities of excitatory amino acid receptors is a phylogenetically conserved feature of the striatum and its non-mammalian homologues. In Huntington's disease, there is substantial depletion of α -amino-3-hydroxy-5-methylisoxazole-4-propionic acid, N-methyl-D-aspartate, and kainate receptors within the striatum. In Parkinson's disease substantia nigra, there is significant loss of N-methyl-D-aspartate and α -amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptors.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41734/1/726_2004_Article_BF00814003.pd

Frequency of hearing defect and ear abnormalities in newborns conceived by assisted reproductive techniques in Royan institute

Background: Assisted reproductive techniques (ART) are used with increasing frequency worldwide. The present research was conducted to determine the effects of ART on hearing defects and ear abnormalities. Materials and Methods: In a descriptive, cross-sectional, non-randomized study, the status of hearing and ear abnormalities was assessed in 300 newborns conceived by ART at Royan Institute, Tehran, Iran. This study was performed over a sixteen month period. Data were collected from parents, otoscopic examinations and transiently evoked otoacoustic emissions (TEOAE) tests of the newborns. The external ear was assessed by otoscopic examination, followed by the TEOAE test (an objective test that does not need the infant's collaboration) which was performed by an audiologist. In this test, the OAE wave was registered after a click (stimulus) at 5-20 millisecond intervals with an 82 dB SPL altitude. Data were analyzed by statistical tests. Results: Of the 300 cases examined by otoscopy, two cases (0.66) had bilateral malformation in the auricle, two (0.66) had unilateral perforation of the tympanic membrane, five (1.66) had unilateral retraction of the tympanic membrane, eight (2.66) had bilateral retraction of the tympanic membrane, one (0.33) had unilateral tympanic membrane inflammation, one (0.33) had bilateral tympanic membrane inflammation and one case (0.33) had wax obstruction of the external ear canal. A total of 289 out of 300 newborns undewent the TEOAE test. Of these, three cases (1.03) did not have a bilateral registered wave and were diagnosed with bilateral hearing loss. Conclusion: This study shows that hearing and ear screening in newborns conceived by ART is contemplative and emphasizes the profitability of continual check up in these infants