Analysis of the Hexagonal Split Ring Resonator using Machine Learning by Considering Split Gap as a Prime Factor

The Hexagonal split-ring resonators (HSRR) are one of the prime elements of metamaterial and patch antenna design in the millimetre-wave range. Even though it's widely used there is no particular mathematic model is available for it. This analysis presents the mathematical nature of the relation between split widths, resonance frequencies; reflection (s11) and mutual coupling (s12) by identifying tend of the data with the aid of machine learning algorithms. The predicted relation will help to design efficient metamaterial, antennas and related appliances

Molecular structure, hirshfeld surface analysis, theoretical investigations and nonlinear optical properties of a novel crystalline chalcone derivative: (E)-1-(5-bromothiophen-2-yl)-3-(p-tolyl)prop-2-en-1-one

In the present work, the crystal structure of a novel chalcone derivative, (E)-1-(5-bromothiophen-2-yl)-3-(p-tolyl) prop-2-en-1-one has been confirmed by X-ray diffraction studies. Hirshfeld surface analysis was carried out to explore the intermolecular interactions. From the Hirshfeld surface analysis it was observed that H⋯H (26.7) and C⋯H (26.3) are the major contributors to the intermolecular interactions which stabilizes the crystal structure. The coordinates were optimized using the density functional theory (DFT) calculations using B3LYP hybrid functions with 6-31G(d) basis set. The structural parameters obtained from XRD studies compliment with those calculated using DFT calculations. The HOMO and LUMO energy gap was found to be 4.1778 eV. The molecular electrostatic potential (MEP) was plotted to identify the possible reactions sites of the molecule. Further, non-linear optical (NLO) properties were investigated by calculating hyperpolarizabilities which indicate that the title compound would be a potential candidate for the NLO applications

Cis and trans isomers of 1-(5-bromothiophen-2-yl)-3-(10-chloroanthracen-9-yl)prop-2-en-1-one: synthesis and characterization

Chalcone derivatives are simple chemical scaffold found in natural products and have been extensively used as an effective template in medicinal chemistry for drug discovery. Two new geometrical isomers of 1-(5-bromothiophen-2-yl)-3-(10-chloroanthracen-9-yl)prop-2-en-1-one were synthesized, isolated and characterized by various spectroscopic techniques (FT-IR, NMR, LC-MS and UV-visible). Two different shaped ( cis and trans ) yellow colored single crystals were obtained by slow evaporation method and the molecular structures were confirmed by X-ray diffraction studies. The cis configuration crystallizes in the monoclinic P2(1)/c space group, whereas, trans configuration crystallizes in the orthorhombic P2(1)2(1)2(1) space group. The conformational changes lead to variations in molecular packing arrangement. In cis , 2-D layer-like architecture is constructed by C-H...O and S...S contacts, whereas, in trans 3-D zig-zag pattern is generated by C-H...O, C-H...Cl and Br...pi interactions. The unique supramolecular topology of the isomers established by diverse intra and intermolecular interactions was analysed by Hirshfeld surfaces, 2D fingerprint plots, 3D energy framework and NCI index model. The Frontier molecular orbitals explored HOMO-LUMO energy gap and associated electronic properties were calculated. The molecular electrostatic potential (MEP) was plotted to identify the reactive sites in the molecule. (C) 2021 Elsevier B.V. All rights reserved

Importance of cannulated prolactin test in the definition of hyperprolactinaemia

Purpose Recent guidelines suggest that a single prolactin measurement is adequate to confirm hyperprolactinaemia. This may lead to unnecessary investigation of artefactual hyperprolactinaemia. Prolactin measurement drawn from an indwelling cannula after rest removes stress as a con-founding variable. The objective was to determine the frequency of true hyperprolactinaemia amongst patients referred following a single prolactin measurement. Methods A cannulated study was considered if prolactin on referral(‘ReferralProlactin’)was\5,500 mU/L(260 ng/mL) but [410 mU/L (19 ng/mL) in males or [510 mU/L (24 ng/mL) in females, irrespective of clinical context. Case-notes of 267 patients undergoing cannulated prolactin measurement over a 10-year period (2000–2010) were reviewed. Pre-existing pituitary disease, dopamine antago-nist use, and macroprolactinaemia were excluded. Morning ante-cubital vein cannulation was followed immediately by withdrawal of ‘Repeat Prolactin’ sample. After 120-min bed-rest, ‘Resting Prolactin’ was withdrawn through the cannula. Results 235 patients were included for analysis. 64 (27 %) were within normal range; following Repeat Prolactin in 41 (17 %) and Resting Prolactin in 23 (9 %) cases. Referral Prolactin was higher in patients with true hyperprolactina-emia, 1,637 ± 100 mU/L (77.2 ± 4.7 ng/mL) than with artefactualhyperprolactinaemia,1,122 ± 68 mU/L(52.9 ± 3.2 ng/mL; P\0.001) but there was substantial overlap. 21 out of 171 cases (12 %) with true hyperprolactinaemia had a macroadenoma. Presenting symptoms did not pre-dict true hyperprolactinaemia. Referral Prolactin of 2,000 mU/L (94 ng/mL) had 97 % specificity to identify true hyperprolactinaemia. Conclusions Reliance on a single, non-rested prolactin value may lead to over-diagnosis of hyperprolactinaemia. A resting sample should be considered with random values \2,000 mU/L (94 ng/mL)

Importance of cannulated prolactin test in the definition of hyperprolactinaemia

Purpose Recent guidelines suggest that a single prolactin measurement is adequate to confirm hyperprolactinaemia. This may lead to unnecessary investigation of artefactual hyperprolactinaemia. Prolactin measurement drawn from an indwelling cannula after rest removes stress as a con-founding variable. The objective was to determine the frequency of true hyperprolactinaemia amongst patients referred following a single prolactin measurement. Methods A cannulated study was considered if prolactin on referral(‘ReferralProlactin’)was____5,500 mU/L(260 ng/mL) but [410 mU/L (19 ng/mL) in males or [510 mU/L (24 ng/mL) in females, irrespective of clinical context. Case-notes of 267 patients undergoing cannulated prolactin measurement over a 10-year period (2000–2010) were reviewed. Pre-existing pituitary disease, dopamine antago-nist use, and macroprolactinaemia were excluded. Morning ante-cubital vein cannulation was followed immediately by withdrawal of ‘Repeat Prolactin’ sample. After 120-min bed-rest, ‘Resting Prolactin’ was withdrawn through the cannula. Results 235 patients were included for analysis. 64 (27 %) were within normal range; following Repeat Prolactin in 41 (17 %) and Resting Prolactin in 23 (9 %) cases. Referral Prolactin was higher in patients with true hyperprolactina-emia, 1,637 ± 100 mU/L (77.2 ± 4.7 ng/mL) than with artefactualhyperprolactinaemia,1,122 ± 68 mU/L(52.9 ± 3.2 ng/mL; P____0.001) but there was substantial overlap. 21 out of 171 cases (12 %) with true hyperprolactinaemia had a macroadenoma. Presenting symptoms did not pre-dict true hyperprolactinaemia. Referral Prolactin of 2,000 mU/L (94 ng/mL) had 97 % specificity to identify true hyperprolactinaemia. Conclusions Reliance on a single, non-rested prolactin value may lead to over-diagnosis of hyperprolactinaemia. A resting sample should be considered with random values ____2,000 mU/L (94 ng/mL)