Near-Infrared Visual Differentiation in Normal and Abnormal Breast Using Hemoglobin Concentrations

Introduction: Near-infrared (NIR) optical imaging is a non-ionizing modality that is emerging as a diagnostic/prognostic tool for breast cancer according to NIR differentiation of hemoglobin (Hb)concentration.Methods: The transmission values of LED-sourced light at 625 nm were measured by power meter to evaluate the optical properties of Hb in breast phantom containing major and minor vessels. For the simulation of blood variations in cancerous breast condition, we prepared 2 concentrations of pre-menopausal Hb and 4 concentrations of post-menopausal Hb and, for comparison with normal tissue, one concentration of Hb injected inside the phantom’s vessels. Imaging procedure on the phantom was also conducted by LED source and CCD camera. The images from the experiments were compared with the results obtained from the images analyzed by MATLAB software. Finally, mammography of phantom including various concentration of Hb was prepared.Results: The transmitting intensities of NIR in blood containing 1, 2 and 4 concentrations of Hb in the major vessels were 52.83 ± 2.85, 43.00 ± 3.11 and 31.17 ± 2.27 μW, respectively, and in minor vessels containing similar Hb concentrations were 73.50 ± 2.43, 60.08 ± 5.09 and 42.42 ± 4.86 μW, respectively. The gray-scale levels on the major vessel were about 96, 124, 162 and on the minor vessel about 72, 100, 130 measured for 1, 2 and 4 Hb concentrations, respectively. The sensitivity and specificity of NIR imaging differentiation were 97.4% and 91.3%, respectively.Conclusion: Significant differences in transmitting intensity, optical imaging as well as software analysis of images were observed for 1, 2 and 4 concentrations of Hb in major and minor breast phantom vessels. Differentiation capability of minor vessels was higher than major vessels for Hb concentrations. Despite a good detection for location of vessels by mammography, it could not show differences between vessels with various concentrations. However, NIR optical imaging demonstrated a good image contrast for showing vessels in terms of concentration. This study recommends NIR optical imaging for prescreening breast cancer due to its potential for early diagnosis

Construction of new 1D and 2D coordination polymers generated from rigid N,N′-bis(4-pyridylmethylene)-1,5-naphthalenediamine ligand:Syntheses, crystal structures and luminescence properties

Treatment of N,N′-bis(4-pyridylmethylene)-1,5-naphthalenediamine (L) with Pb(OAc)2/KBr, Cu(acac)2, and Cu(OAc)2 afforded three new coordination polymers [Pb(μ-L)(μ-Br)2]n (1), [Cu(μ-L)(acac)2]n (2), and [Cu2(μ-L)(μ-OAc)4]n (3). These coordination polymers have been structurally characterized by single crystal X-ray diffraction. Compound 1 has a 2D sheet structure in which the lead(II) centers are bridged by both L and bromide ligands. Compound 2 adopts a 1D neutral coordination chain and consists of bis(2,4-pentanedionato) copper(II) units connected by rigid bridging L ligands. The structure of compound 3 also adopts a 1D neutral coordination chain in which two copper centers are connected through four acetate groups to form a Cu(OAc)4Cu paddle-wheel-type cage between two bridging L ligands. The FT-IR spectra, thermal behavior and photoluminescence properties of these coordination polymers have also been investigated.</p

Effect of magnetic nanoparticles on the nematic-smectic-A phase transition

Recent experiments on mixed liquid crystals have highlighted the hugely significant role of ferromagnetic nanoparticle impurities in defining the nematic-smectic-A phase transition point. Structured around a Flory-Huggins free energy of isotropic mixing and Landau-de Gennes free energy, this article presents a phenomenological mean-field model that quantifies the role of such impurities in analyzing thermodynamic phases, in a mixture of thermotropic smectic liquid crystal and ferromagnetic nanoparticles. First we discuss the impact of ferromagnetic nanoparticles on the isotropic-ferronematic and ferronematic-ferrosmectic phase transitions and their transition temperatures. This is followed by plotting and discussing various topologies in the phase diagrams. Our model results indicate that there exists a critical concentration of nanoparticle impurities for which the second order N-SmA transition becomes first order at a tricritical point. Calculations based on this model show remarkable agreement with experiment

Collaborative information behaviour of graduate students in Tehran University of Medical Sciences (TUMS)

Collaborative information behavior is an important and growing area of research in the field of information behavior. Although collaboration is a key component of work in organizational and other settings Studies when two or more actors identify, seek, search, and use information to accomplish a task. This poster reports on a recent research investigating the collaborative information behavior of graduate students in Tehran University of Medical sciences, students of in the context of Medical science research groups projects. A total of 25 graduate students who participated in a collaborative research project were asked to complete process surveys throughout the project. Data analysis showed that collaborative information behaviors dynamically occur in different stages of the project through different levels depending on the corresponding project tasks that trigger different collaborative information related activities.published or submitted for publicationis peer reviewe

Contribution of environment polarity effects on the nonlinear hyperpolarizability and linear optical characteristics of some phenothiazines

Solvents as complex environments can induce considerable effects on the physical, chemical, and biological properties of solute molecules. In this work, solvent polarity sensitive characteristics of phenothiazines were studied by using spectroscopic technique. In this case, the interactional behavior of selected samples was investigated by Kamlet-Abboud-Taft and Catalan models. Moreover, the results from the spectroscopic technique provide a proper condition for providing a new method for investigation of environment polarity effects on the molecular first and second order hyperpolarizability. According to the results, solute�solvent specific and nonspecific interactions with different contributions tend to modify the value of molecular hyperpolarizability. In this case, the studies on the contribution of various molecular interactions can indicate some advantages such as decreasing the complexity of investigations on the environment polarity effects on the molecular hyperpolarizability and provide an effective method for controlling molecular first and second order hyperpolarizability. Therefore, the results can give useful information about the capability of selected samples for various applications in optics. © 2021 Elsevier B.V

Study of the variation of intra/intermolecular interactions and configuration of a group of Enone anticancer drugs as a result of solvation

During the last decade, the naturally occurring yellow Enone has drawn considerable attention due to its wide applications in biological, medical and pharmaceutical phenomena. The properties of molecular surrounding media can modify its various properties. In this work, spectral properties of three Enone derivatives were studied in various solvents by spectroscopic and theoretical techniques. As expected, the results show that photo-physical behavior of the Enone solutes depends strongly on the solvent�solute interactions and the nature of the solvent, along with different attached groups on the solute structures. In order to investigate the solvent�solute interactions and media effect on spectral variations, linear solvation energy relationships suggested by Kamlet�Abboud�Taft and Catalán parameters, were used. It was observed that the excited state dipole moments of Enone drugs are higher than those in the ground state, which increase the probability of charge transfer mechanism. The experimental results were also confirmed by density functional theory and its related time-dependent calculations including NBO analysis. The achieved results would help us to better understand the photo-physical properties and reveal essential information about the interaction of structural functional groups of Enone drugs in different media. © 201