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https://www.readbyqxmd.com/read/28535909/dynamic-simulation-and-doppler-ultrasonography-validation-of-blood-flow-behavior-in-abdominal-aortic-aneurysm
#1
Cristian C Botar, Árpád Á Tóth, Olivera R Klisurić, Dijana D Nićiforović, Viktorija A Vučaj Ćirilović, Viktor E Till
Criteria for rupture prediction of Abdominal Aortic Aneurysm (AAA) are based only on the diameter of AAA. This method does not consider complex hemodynamic forces exerted on AAA wall. The methodology used in our study combines Computer-Aided Design (CAD) with Computational Fluid Dynamics (CFD). Three-dimensional vascular structures reconstructions were based on Computed Tomography (CT) images and CAD. CFD theory was used for mathematical modeling and simulations. In this way, dynamic behavior of blood flow in bounded three-dimensional space was described...
May 2017: Physica Medica: PM
https://www.readbyqxmd.com/read/28513677/regular-and-red-shifted-fluorescence-of-the-donor-acceptor-compound-5-1h-pyrrole-1-yl-thiophenecarbonitrile-tcn-is-efficiently-quenched-by-internal-modes-of-thiophene
#2
Mercedes V Bohnwagner, Irene Burghardt, Andreas Dreuw
The photochemical properties of thiophene analogs of N-pyrrolobenzonitrile (PBN), notably the two isomers 5-(1H-pyrrole-1-yl)thiophene-2-carbonitrile (2-TCN) and 5-(1H-pyrrole-1-yl)thiophene-3-carbonitrile (3-TCN) have been investigated. The aim of this study is to reveal whether the donor-acceptor compound TCN shows a fluorescence behavior similar to other benzonitrile derivatives like PBN and N,N-dimethylaminobenzonitrile (DMABN). For this purpose high-level ab initio methods have been employed comprising approximate coupled cluster (CC2) methods, the algebraic-diagramatic construction scheme for the polarization propagator (ADC(2) and ADC(3)) as well as time-dependent density functional theory (TDDFT)...
May 17, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28505565/dft-and-td-dft-theoretical-studies-on-photo-induced-electron-transfer-process-on-cefamandole-c60-nano-complex
#3
Avat Arman Taherpour, Morteza Jamshidi, Omid Rezaei
The C60 fullerene displays a considerable electronegativity. It has a unique photophysical and electrochemical behavior that can be used as a suitable drug carrier. In the present study, the interaction of C60 fullerene as an electron recipient with the Cefamandole antibiotic was investigated in both ground and excited states using DFT and TD-DFT methods. The study of the interaction of C60 and Cefamandole via electron localization function (ELF) and reduced density gradient (RDG) revealed that the complex formation is of van der Waals type...
April 27, 2017: Journal of Molecular Graphics & Modelling
https://www.readbyqxmd.com/read/28493805/creating-three-dimensional-printed-models-of-acetabular-fractures-for-use-as-educational-tools
#4
Matthew S Manganaro, Yoav Morag, William J Weadock, Corrie M Yablon, Kara Gaetke-Udager, Erica B Stein
Acetabular fractures are frequently encountered in some clinical practices, and the precise classification of these fractures greatly influences treatments and outcomes. The authors identified the need for an educational aid when teaching acetabular fracture classifications, given the complex spatial anatomy and the nonintuitive classification system that is commonly used. Three-dimensional ( 3D three-dimensional ) printing is an evolving technique that has applications as an educational aid, providing the student with a tangible object to interact with and learn from...
May 2017: Radiographics: a Review Publication of the Radiological Society of North America, Inc
https://www.readbyqxmd.com/read/28493717/-2-2-type-reaction-of-metal-metal-%C3%AF-bond-with-fullerene-forming-an-%C3%AE-1-c60-metal-complex-mechanistic-details-of-formation-reaction-and-prediction-of-a-new-%C3%AE-1-c60-metal-complex
#5
Hong Zheng, Xiang Zhao, Shigeyoshi Sakaki
C60[CpRu(CO)2]2 is only one transition-metal fullerene complex with pure η(1)-coordinated bonds, which was recently synthesized through the reaction between dinuclear Ru complex [CpRu(CO)2]2 and C60. Though new properties can be expected in the η(1)-coordinated metal-fullerene complex, its characteristic features are unclear, and the [2 + 2]-type formation reaction is very slow with a very small yield. A density functional theory study discloses that the η(1)-coordinated bond is formed by a large overlap between the Ru dσ orbital and C pσ one involved in the lowest unoccupied molecular orbital (LUMO) (π*) of C60 unlike the well-known η(2)-coordinated metal-fullerene complex which has a π-type coordinate bond with metal dπ orbital...
May 11, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28475959/a-turn-on-type-stimuli-responsive-fluorescent-dye-with-specific-solvent-effect-implication-for-a-new-prototype-of-paper-using-water-as-the-ink
#6
Xiaochen Hu, Yang Liu, Yuai Duan, Jingqi Han, Zhongfeng Li, Tianyu Han
In this study, we reported the photoluminescence (PL) behaviour of a new intramolecular charge transfer (ICT) compound, ((E)-2-(((2-hydroxynaphthalen-1-yl)methylene)amino)benzoic acid, (HABA), which shows ICT solvent effect in aprotic solvents as confirmed by absorption and emission spectra. While in protic solvents including water and ethanol, the charge transfer (CT) band significantly reduces. Remarkable fluorescence enhancement in the blue region was also observed for HABA in polar protic solvents. We described such phenomena as "specific solvent effect"...
April 29, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28465264/quantitative-susceptibility-mapping-as-a-possible-tool-to-radiographically-diagnose-sentinel-headache-associated-with-intracranial-aneurysm-case-report
#7
Daichi Nakagawa, Cameron Cushing, Yasunori Nagahama, Lauren Allan, David Hasan
BACKGROUND: Sentinel headache (SH) is estimated to occur prior to rupture of an aneurysm in 15-60% of aneurysmal subarachnoid hemorrhage (aSAH) cases. Non-contrasted computed tomography (CT) of brain and lumbar puncture are both negative, by definition, in patients presenting with SH. One of the theories explaining this phenomenon is micro-hemorrhage (MH) from the aneurysm wall contributing to iron deposition in the interface between the aneurysm wall and brain parenchyma. Quantitative susceptibility mapping (QSM) is a recently introduced magnetic resonance imaging (MRI) technique that has been shown capable of localizing the deposition of paramagnetic metals, particularly ferric iron...
April 29, 2017: World Neurosurgery
https://www.readbyqxmd.com/read/28448902/surface-modified-tio2-nanoparticles-with-ascorbic-acid-antioxidant-properties-and-efficiency-against-dna-damage-in-vitro
#8
Vladan Bajić, Biljana Spremo-Potparević, Lada Živković, Andrea Čabarkapa, Jelena Kotur-Stevuljević, Esma Isenović, Dušan Sredojević, Ivana Vukoje, Vesna Lazić, S Phillip Ahrenkiel, Jovan M Nedeljković
The antigenotoxic and antioxidative properties of surface-modified TiO2 nanoparticles (NPs) with ascorbic acid (AA) were compared with those of constituents (free AA and bare TiO2 NPs). Colloids consisting of the TiO2 NPs with anatase crystal structure were prepared by acidic hydrolysis of TiCl4. The synthesized TiO2 NPs were characterized using transmission electron microscopy and X-ray diffraction analysis. The charge transfer (CT) complex formation between surface Ti atoms and AA is indicated by immediate appearance of red color...
April 14, 2017: Colloids and Surfaces. B, Biointerfaces
https://www.readbyqxmd.com/read/28436852/frequency-selective-computed-tomography-applications-during-periodic-thoracic-motion
#9
Jacob Herrmann, Eric A Hoffman, David W Kaczka
We seek to use computed tomography (CT) to characterize regional lung parenchymal deformation during highfrequency and multi-frequency oscillatory ventilation. Periodic motion of thoracic structures results in artifacts of CT images obtained by standard reconstruction algorithms, especially for frequencies exceeding that of the X-ray source rotation. In this study, we propose an acquisition and reconstruction technique for high resolution imaging of the thorax during periodic motion. Our technique relies on phase-binning projections according to the frequency of subject motion relative to the scanner rotation, prior to volumetric reconstruction...
April 18, 2017: IEEE Transactions on Medical Imaging
https://www.readbyqxmd.com/read/28426947/structural-neuroplasticity-of-the-superior-temporal-plane-in-early-and-late-blindness
#10
Hicret Atilgan, Olivier Collignon, Uri Hasson
Blindness is associated with well-documented changes to the morphometry and function of the occipital cortex. By comparison, its impact on the perisylvian regions in the superior temporal plane (STP) is poorly understood, with many studies reporting null findings on this issue. Here we re-approach this question using a morphometric analysis that relied on fine-scale, manual annotation of 13 sub-regions within the STP and that quantified both univariate and multivariate differences in morphometry. We applied these analyses to both cortical thickness (CT) and surface area (SA) data from congenitally and late blind, as compared to two matched sighted control groups...
April 17, 2017: Brain and Language
https://www.readbyqxmd.com/read/28406648/mechanisms-of-change-in-cognitive-therapy-for-major-depressive-disorder-in-the-community-mental-health-setting
#11
Paul Crits-Christoph, Robert Gallop, Caroline K Diehl, Seohyun Yin, Mary Beth Connolly Gibbons
OBJECTIVE: This study examined the relation of change in theory-relevant cognitive variables to depressive symptom change over the course of cognitive therapy, as well as the specificity of change mechanisms to cognitive therapy as compared with dynamic therapy. METHOD: There were 237 adult outpatients who were randomized to either cognitive (n = 119) or dynamic (n = 118) therapy for major depressive disorder in a community mental health setting. Assessments of compensatory skills (Ways of Responding Community Version and Self-Report Version), dysfunctional attitudes (Dysfunctional Attitudes Scale), and depressogenic schemas (Psychological Distance Scaling Task) were obtained at baseline and months 1, 2, and 5 following baseline...
June 2017: Journal of Consulting and Clinical Psychology
https://www.readbyqxmd.com/read/28388105/charge-transfer-excitations-from-particle-particle-random-phase-approximation-opportunities-and-challenges-arising-from-two-electron-deficient-systems
#12
Yang Yang, Adriel Dominguez, Du Zhang, Vitalij Lutsker, Thomas A Niehaus, Thomas Frauenheim, Weitao Yang
The particle-particle random phase approximation (pp-RPA) is a promising method for studying charge transfer(CT) excitations. Through a detailed analysis on two-electron deficient systems, we show that the pp-RPA is always able to recover the long-distance asymptotic -1/R trend for CT excitations as a result of the concerted effect between orbital energies and the pp-RPA kernel. We also provide quantitative results for systems with relatively short donor-acceptor distances. With conventional hybrid or range-separated functionals, the pp-RPA performs much better than time-dependent density functional theory (TDDFT), although it still gives underestimated results which are not as good as TDDFT with system-dependent tuned functionals...
March 28, 2017: Journal of Chemical Physics
https://www.readbyqxmd.com/read/28321787/a-mathematical-theory-of-shape-and-neuro-fuzzy-methodology-based-diagnostic-analysis-a-comparative-study-on-early-detection-and-treatment-planning-of-brain-cancer
#13
Subrata Kar, D Dutta Majumder
BACKGROUND: Investigation of brain cancer can detect the abnormal growth of tissue in the brain using computed tomography (CT) scans and magnetic resonance (MR) images of patients. The proposed method classifies brain cancer on shape-based feature extraction as either benign or malignant. The authors used input variables such as shape distance (SD) and shape similarity measure (SSM) in fuzzy tools, and used fuzzy rules to evaluate the risk status as an output variable. We presented a classifier neural network system (NNS), namely Levenberg-Marquardt (LM), which is a feed-forward back-propagation learning algorithm used to train the NN for the status of brain cancer, if any, and which achieved satisfactory performance with 100% accuracy...
March 20, 2017: International Journal of Clinical Oncology
https://www.readbyqxmd.com/read/28294604/solvent-controlled-doublet-emission-of-an-organometallic-gold-i-complex-with-a-polychlorinated-diphenyl-4-pyridyl-methyl-radical-ligand-dual-fluorescence-and-enhanced-emission-efficiency
#14
Yasuyo Ogino, Tetsuro Kusamoto, Yohei Hattori, Masaki Shimada, Mizuho Tsuchiya, Yoshinori Yamanoi, Eiji Nishibori, Kunihisa Sugimoto, Hiroshi Nishihara
A paramagnetic, luminescent organometallic gold(I) complex Au(I)(C6F5)(PyBTM), where PyBTM is a photostable fluorescent polychlorinated diphenyl(4-pyridyl)methyl radical, was prepared, and its crystal and electronic structures and magnetic and optical properties were investigated. Magnetic studies using electron spin resonance spectroscopy and a superconducting quantum interference device magnetometer indicated the existence of S = (1)/2 spin per molecule, with the spin density distributed mainly on the PyBTM ligand...
April 3, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28282451/c-tactile-afferent-stimulating-touch-carries-a-positive-affective-value
#15
Ralph Pawling, Peter R Cannon, Francis P McGlone, Susannah C Walker
The rewarding sensation of touch in affiliative interactions is hypothesized to be underpinned by a specialized system of nerve fibers called C-Tactile afferents (CTs), which respond optimally to slowly moving, gentle touch, typical of a caress. However, empirical evidence to support the theory that CTs encode socially relevant, rewarding tactile information in humans is currently limited. While in healthy participants, touch applied at CT optimal velocities (1-10cm/sec) is reliably rated as subjectively pleasant, neuronopathy patients lacking large myelinated afferents, but with intact C-fibres, report that the conscious sensation elicited by stimulation of CTs is rather vague...
2017: PloS One
https://www.readbyqxmd.com/read/28225355/assessing-cardiac-function-from-total-variation-regularized-4d-c-arm-ct-in-the-presence-of-angular-undersampling
#16
O Taubmann, V Haase, G Lauritsch, Y Zheng, G Krings, J Hornegger, A Maier
Time-resolved tomographic cardiac imaging using an angiographic C-arm device may support clinicians during minimally invasive therapy by enabling a thorough analysis of the heart function directly in the catheter laboratory. However, clinically feasible acquisition protocols entail a highly challenging reconstruction problem which suffers from sparse angular sampling of the trajectory. Compressed sensing theory promises that useful images can be recovered despite massive undersampling by means of sparsity-based regularization...
April 7, 2017: Physics in Medicine and Biology
https://www.readbyqxmd.com/read/28216521/technique-and-theory-of-hollow-fiber-phantom-for-cerebral-ct-perfusion
#17
Eiji Okaniwa, Hiroyuki Hashimoto, Kazufumi Suzuki, Hiroshi Iimura, Shingo Suzaki, Kayoko Abe, Mituhiro Ejima, Shuji Sakai
We developed a phantom using a hollow-fiber hemodialyzer to evaluate the quantitative reliability of cerebral computed tomography (CT) perfusion. Our phantom consisted of a hollow-fiber hemodialyzer and a syringe-shaped X-ray device made up of resin. The phantom can give theoretical true values for cerebral blood volume, cerebral blood flow, and mean transit time. We compared the values measured in the phantom with predicted theoretical values. The purpose of the current report is to describe the theory and experimental technique used to obtain an absolute value in a phantom...
2017: Nihon Hoshasen Gijutsu Gakkai Zasshi
https://www.readbyqxmd.com/read/28186469/blood-based-nucleic-acid-biomarkers-as-a-potential-tool-to-determine-radiation-therapy-response-in-non-small-cell-lung-cancer
#18
REVIEW
Christopher R Deig, Marc S Mendonca, Tim Lautenschlaeger
Lung cancer is the leading cause of cancer deaths worldwide, with smoking as the main risk factor. The use of low-dose computed tomography (LDCT) as a screening method has shown a 20% lung cancer specific mortality benefit; however, widespread implementation is estimated to add $1.3-$2.0 billion in annual national health care expenditures. Blood-based microRNAs (miRNAs) have been investigated in detail and found to be potentially useful biomarkers indicating the presence of lung cancer, especially when used as a companion test to LDCT...
March 2017: Radiation Research
https://www.readbyqxmd.com/read/28149991/exciton-vibrational-resonance-and-dynamics-of-charge-separation-in-the-photosystem-ii-reaction-center
#19
Vladimir I Novoderezhkin, Elisabet Romero, Javier Prior, Rienk van Grondelle
The dynamics of charge separation in the photosystem II reaction center (PSII-RC) in the presence of intramolecular vibrations with their frequency matching the energy gap between the exciton state acting as the primary electron donor and the first charge-transfer (CT) state are investigated. A reduced PSII-RC 4-state model explicitly including a CT state is analyzed within Redfield relaxation theory in the multidimensional exciton-vibrational (vibronic) basis. This model is used to study coherent energy/electron transfers and their spectral signatures obtained by two-dimensional electronic spectroscopy (2DES)...
February 2, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28147535/simulating-the-absorption-spectra-of-helium-clusters-n%C3%A2-%C3%A2-70-150-231-300-using-a-charge-transfer-correction-to-superposition-of-fragment-single-excitations
#20
Qinghui Ge, Yuezhi Mao, Alec F White, Evgeny Epifanovsky, Kristina D Closser, Martin Head-Gordon
Simulations of the n = 2 absorption spectra of HeN (N = 70, 150, 231, 300) clusters are reported, with nuclear configurations sampled by path integral molecular dynamics. The electronic structure is treated by a new approach, ALMO-CIS+CT, which is a formulation of configuration interaction singles (CIS) based on absolutely localized molecular orbitals (ALMOs). The method generalizes the previously reported ALMO-CIS model [K. D. Closser et al. J. Chem. Theory Comput. 11, 5791 (2015)] to include spatially localized charge transfer (CT) effects...
January 28, 2017: Journal of Chemical Physics
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