Computed Tomography Pulmonary Angiography during Pregnancy: Radiation Dose of Commonly Used Protocols and the Effect of Scan Length Optimization

Babs M.F. Hendriks,Roald S. Schnerr,Gianluca Milanese,Cécile R.L.P.N. Jeukens,Sandra Niesen,Nienke G. Eijsvoogel,Joachim E. Wildberger,Marco Das 대한영상의학회 2019 Korean Journal of Radiology Vol.20 No.2

Objective: To evaluate the radiation dose for pregnant women and fetuses undergoing commonly used computed tomography of the pulmonary arteries (CTPA) scan protocols and subsequently evaluate the simulated effect of an optimized scan length. Materials and Methods: A total of 120 CTPA datasets were acquired using four distinctive scan protocols, with 30 patients per protocol. These datasets were mapped to Cristy phantoms in order to simulate pregnancy and to assess the effect of an effective radiation dose (in mSv) in the first, second, or third trimester of pregnancy, including a simulation of fetal dose in second and third trimesters. The investigated scan protocols involved a 64-slice helical scan at 120 kVp, a high-pitch dual source acquisition at 100 kVp, a dual-energy acquisition at 80/140 kVp, and an automated-kV-selection, high pitch helical scan at a reference kV of 100 kVref. The effective dose for women and fetuses was simulated before and after scan length adaptation. The original images were interpreted before and after scan length adaptations to evaluate potentially missed diagnoses. Results: Large inter-scanner and inter-protocol variations were found; application of the latest technology decreased the dose for non-pregnant women by 69% (7.0–2.2 mSv). Individual scan length optimization proved safe and effective, decreasing the fetal dose by 76–83%. Nineteen (16%) cases of pulmonary embolism were diagnosed and, after scan length optimization, none were missed. Conclusion: Careful CTPA scan protocol selection and additional optimization of scan length may result in significant radiation dose reduction for a pregnant patient and her fetus, whilst maintaining diagnostic confidence.

Proteomic changes induced by histone demethylase JMJD3 in TNF alpha-treated human monocytic (THP-1) cells

Das, A.,Das, N.D.,Jung, K.H.,Park, J.H.,Lee, H.T.,Han, D.,Choi, M.R.,Kang, S.C.,Chai, Y.G. Pergamon Press 2013 Molecular immunology Vol.56 No.1

JMJD3, a Jumonji C family histone demethylase, plays an important role in the regulation of inflammation induced by the transcription factor nuclear factor-kappa B (NF-κB) in response to various stimuli. JMJD3 is a histone-3 lysine-27 trimethylation (H3K27me3) demethylase, a histone mark associated with transcriptional repression and activation of a diverse set of genes. The present study assessed stable JMJD3 knockdown (KD)-dependent proteomic profiling in human leukemia monocyte (THP-1) cells to analyze the JMJD3-mediated differential changes of marker expression in inflammatory cells. To analyze the protein expression profile of tumor necrosis factor-alpha (TNF-α)-stimulated JMJD3-kd THP-1 cells, we employed matrix-assisted-laser-desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS). Additionally, Ingenuity Pathways Analysis (IPA) was applied to establish the molecular networks. A comparative proteomic profile was determined in TNF-α-treated both of JMJD3-kd THP-1 cells and THP-1 scrambled (sc) cells. The expression of tripartite motif protein (TRIM5), glutathione peroxidase (GPx), glia maturation factor-γ (GMFG), caspase recruitment domain family, member 14 (CARMA2), and dUTP pyrophosphatase were significantly down-regulated, whereas heat shock protein beta-1 (HspB1) and prohibition were significantly up-regulated in JMJD3-kd THP-1 cells. The molecular and signaling networks of the differentially expressed proteins in JMJD3-kd THP-1 cells were determined by IPA. The molecular network signatures and functional proteomics obtained in this study may facilitate the suppression of different key inflammatory regulators through JMJD3-attenuation, which would be crucial to evaluate potential therapeutic targets and to elucidate the molecular mechanism of JMJD3-kd dependent effects in THP-1 cells.

Searching for Resonances in the Unbound 6Be Nucleus by Using a Radioactive 7Be Beam

채경육,D. W. Bardayan,J. C. Blackmon,M. S. Smith,A. E. Champagne,J. J. Das,R. P. Fitzgerald,D. W. Visser,V. Guimaraes,K. L. Jones,S. D. Pain,J. S. Thomas,M. S. Johnson,R. L. Kozub,R. J. Livesay,Z. Ma,C. 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.61 No.11

Knowledge of the ³He(³He,²<i>p</i>)⁴He reaction is important for understanding stellar burning and solar neutrino production. Previous measurements have found a surprisingly large rise in the cross section at low energies that could be due to a low-energy resonance in the ³He + ³He (⁶Be) system or electron screening. In the ⁶Be nucleus, however, no excited states have been observed above the first 2⁺ state at <i>E_x</i> = 1.67 MeV up to 23 MeV, even though several are expected. The ²H(⁷Be,³H)⁶Be reaction has been studied for the first time to search for resonances in the ⁶Be nucleus that may affect our understanding of the ³He(³He,²<i>p,</i>)⁴He reaction. A 100-MeV radioactive ⁷Be beam from the Holifield Radioactive Ion Beam Facility (HRIBF) was used to bombard CD₂ targets, and tritons were detected by using the silicon detector array (SIDAR). A combination of reaction mechanisms appears to be necessary to explain the observed triton energy spectrum.

Growth and characterization of pure and doped L-Lysine monohydrochloride dihydrate (L-LMHCl) nonlinear optical single crystals

R. Robert,C. Justin Raj,S. Jerome Das 한국물리학회 2010 Current Applied Physics Vol.10 No.2

Semi-organic nonlinear optical single crystals of pure, Ni2+ and Cd2+ doped L-Lysine monohydrochloride dihydrate (L-LMHCl) were grown from aqueous solution by slow evaporation technique. Single crystal Xray diffraction analysis reveal that the pure and doped L-LMHCl crystals belong to monoclinic system with the space group P21. The presence of functional groups present in the pure and doped crystals was determined qualitatively by using Fourier Transform Infrared (FTIR) spectroscopy. Optical absorption studies reveal very low absorption for the doped crystal than that of the pure crystal. Dielectric studies have been carried out for the grown crystals and the results were discussed in detail.

Radio and infrared study of southern H II regions G346.056−0.021 and G346.077−0.056

Das, S. R.,Tej, A.,Vig, S.,Liu, T.,Ghosh, S. K.,Chandra, C. H. I. EDP Sciences 2018 Astronomy and astrophysics Vol.612 No.-

<P><I>Aim.</I> We present a multiwavelength study of two southern Galactic H II regions G346.056−0.021 and G346.077−0.056 which are located at a distance of 10.9 kpc. The distribution of ionized gas, cold and warm dust, and the stellar population associated with the two H II regions are studied in detail using measurements at near-infrared, mid-infrared, far-infrared, submillimeter and radio wavelengths.</P><P><I>Methods.</I> The radio continuum maps at 1280 and 610 MHz were obtained using the Giant Metrewave Radio Telescope to probe the ionized gas. The dust temperature, column density, and dust emissivity maps were generated using modified blackbody fits in the far-infrared wavelength range 160-500 <I>μ</I>m. Various near- and mid-infrared color and magnitude criteria were adopted to identify candidate ionizing star(s) and the population of young stellar objects in the associated field.</P><P><I>Results.</I> The radio maps reveal the presence of diffuse ionized emission displaying distinct cometary morphologies. The 1280 MHz flux densities translate to zero age main sequence spectral types in the range O7.5V-O7V and O8.5V-O8V for the ionizing stars of G346.056−0.021 and G346.077−0.056, respectively. A few promising candidate ionizing star(s) are identified using near-infrared photometric data. The column density map shows the presence of a large, dense dust clump enveloping G346.077−0.056. The dust temperature map shows peaks towards the two H II regions. The submillimeter image shows the presence of two additional clumps, one being associated with G346.056−0.021. The masses of the clumps are estimated to range between ~1400 and 15250 <I>M</I>⊙. Based on simple analytic calculations and the correlation seen between the ionized gas distribution and the local density structure, the observed cometary morphology in the radio maps is better explained invoking the champagne-flow model.</P>

Bounds on the entries of the principal eigenvector of the distance signless Laplacian matrix

Das, K.Ch.,da Silva Junior, C.M.,de Freitas, M.A.A.,Del-Vecchio, R.R. North Holland [etc.] 2015 Linear Algebra and its Applications Vol.483 No.-

The distance signless Laplacian spectral radius of a connected graph G is the largest eigenvalue of the distance signless Laplacian matrix of G, defined as D<SUP>Q</SUP>(G)=Tr(G)+D(G), where D(G) is the distance matrix of G and Tr(G) is the diagonal matrix of vertex transmissions of G. In this paper we determine upper and lower bounds on the minimal and maximal entries of the principal eigenvector of D<SUP>Q</SUP>(G) and characterize the extremal graphs. In addition, we obtain a lower bound on the distance signless Laplacian spectral radius of G based on its order and independence number, and characterize the extremal graph.

Bulk crystal growth and characterization of non-linear optical bisthiourea zinc chloride single crystal by unidirectional growth method

R. Uthrakumar,C. Vesta,C. Justin Raj,S. Krishnan,S. Jerome Das 한국물리학회 2010 Current Applied Physics Vol.10 No.2

The unidirectional crystal growth method has been employed for the bulk growth of semi-organic nonlinear optical bisthiourea zinc chloride single crystal along a-axis with high solute-crystal conversion efficiency. Single crystal X-ray diffraction studies confirm the orthorhombic structure. Optical studies reveal very high transmission of the crystal along the growth axis. Dielectric study shows that the dielectric constant decreases with increase in frequency. Microhardness measurements along the growth axis enunciate the favorable hardness behavior.

Changes in Skin Temperature and Physiological Reactions in Murrah Buffalo During Solar Exposure in Summer

Das, S.K.,Upadhyay, R.C.,Madan, M.L. Asian Australasian Association of Animal Productio 1997 Animal Bioscience Vol.10 No.5

Six adult female Murrah buffaloes of about 12 years were exposed to solar radiation during summer when minimum and maximum ambient temperatures were 27.1 and $44.1^{\circ}C$, respectively. The skin surface temperature at forehead, middle pinna, neck, rump, foreleg, hind legs were recorded using non-contact temperature measuring instrument and respiration rate and rectal temperature were measured throughout the 24 hours starting from 6:30 AM. The diurnal fluctuations and temperature gradients have been reported for buffaloes. During summer when ambient temperature and solar radiation was maximum, adult buffaloes were not able to maintain their thermal balance even after increasing the pulmonary frequency 5 - 6 times. The changes in skin temperature at various sites indicate that the temperature of skin surface not only varies in relation to exposure but also due to water diffusion and evaporation.

Carboxylated Nitrile Elastomer/Filler Nanocomposite

R. N. Mahaling,G. K. Jana,C. K. Das,H. Jeong,C. S. Ha 한국고분자학회 2005 Macromolecular Research Vol.13 No.4

FLUORESCENCE STUDY OF CdSe QUANTUM DOTS SUSPENDED IN LIQUID PARAFFIN

S. C. DEY,R. DAS,S. S. NATH,R. BHATTACHERJEE 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2010 NANO Vol.5 No.6

Here we report a safer, easier, and quicker chemical route for synthesis of CdSe quantum dots (QDs), followed by their characterizations by UV/vis Spectroscopy (UV/vis), X-ray diffraction study (XRD), High Resolution Transmission Electron Microscopy (HRTEM) and fluorescence (FL) spectroscopy. The average size of the quantum dots is 7.5 nm. Fluorescence study reveals that CdSe quantum dots emit green light when excited by optical source of wavelength of 550 nm or less.