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Ruhuai Mei, Cuiju Zhu, Lutz Ackermann
C-H arylations of weakly coordinating benzoic acids were achieved by versatile ruthenium(ii) catalysis with ample substrate scope. Thus, user-friendly ruthenium(ii) biscarboxylate complexes modified with tricyclohexylphosphine enabled C-H functionalizations with aryl electrophiles. The unique versatility of the ruthenium(ii) catalysis manifold was reflected by facilitating effective C-H activations with aryl, alkenyl and alkynyl halides.
October 21, 2016: Chemical Communications: Chem Comm
J Mushanyu, F Nyabadza, G Muchatibaya, A G R Stewart
The abuse of drugs is now an epidemic globally whose control has been mainly through rehabilitation. The demand for drug abuse rehabilitation has not been matched with the available capacity resulting in limited placement of addicts into rehabilitation. In this paper, we model limited rehabilitation through the Hill function incorporated into a system of nonlinear ordinary differential equations. Not every member of the community is equally likely to embark on drug use, risk structure is included to help differentiate those more likely (high risk) to abuse drugs and those less likely (low risk) to abuse drugs...
October 20, 2016: Bulletin of Mathematical Biology
Liangyan Gui, Xiaoying Tang, José M F Moura
We propose a geodesic distance on a Grassmannian manifold that can be used to quantify the shape progression patterns of the bilateral hippocampi, amygdalas, and lateral ventricles in healthy control (HC), mild cognitive impairment (MCI), and Alzheimer's disease (AD). Longitudinal magnetic resonance imaging (MRI) scans of 754 subjects (3092 scans in total) were used in this study. Longitudinally, the geodesic distance was found to be proportional to the elapsed time separating the two scans in question. Cross-sectionally, utilizing a linear mixed-effects statistical model, we found that each structure's annualized rate of change in the geodesic distance followed the order of AD > MCI > HC, with statistical significance being reached in every case...
October 15, 2016: NeuroImage
Archontis Giannakidis, Gerd Melkus, Guang Yang, Grant T Gullberg
Diffusion tensor magnetic resonance imaging (DT-MRI) allows a unique insight into the microstructure of highly-directional tissues. The selection of the most proper distance function for the space of diffusion tensors is crucial in enhancing the clinical application of this imaging modality. Both linear and nonlinear metrics have been proposed in the literature over the years. The debate on the most appropriate DT-MRI distance function is still ongoing. In this paper, we presented a framework to compare the Euclidean, affine-invariant Riemannian and log-Euclidean metrics using actual high-resolution DT-MRI rat heart data...
November 7, 2016: Physics in Medicine and Biology
Sabine Fuchs, Britta Olberg, Dimitra Panteli, Matthias Perleth, Reinhard Busse
OBJECTIVES: Health Technology Assessment (HTA) of Medical devices (MDs) and MD-based procedures can be challenging due to the unique features and particularities of this group of technologies, such as device-operator interaction. The aim of this study was to (1) clarify, and supplement earlier findings on European HTA institutions' structural, procedural and methodological characteristics with regard to the assessment of MDs and to (2) capture the institutions' perceptions regarding challenges and future trends...
September 14, 2016: Health Policy
Benjamin Kick, Samantha Hensler, Florian Praetorius, Hendrik Dietz, Dirk Weuster-Botz
The bacteriophage M13 has found frequent applications in nanobiotechnology due to its chemically and genetically tunable protein surface and its ability to self-assemble into colloidal membranes. Additionally, its single-stranded (ss) genome is commonly used as scaffold for DNA origami. Despite the manifold uses of M13, upstream production methods for phage and scaffold ssDNA are underexamined with respect to future industrial usage. Here, the high-cell-density phage production with Escherichia coli as host organism was studied in respect of medium composition, infection time, multiplicity of infection and specific growth rate...
October 17, 2016: Biotechnology and Bioengineering
Soumitra Shome, Anupam Das Talukdar, Manabendra Dutta Choudhury, Mrinal Kanti Bhattacharya, Hrishikesh Upadhyaya
OBJECTIVES: Nanotechnology-based drug delivery systems can resolve the poor bioavailability issue allied with curcumin. The therapeutic potential of curcumin can be enhanced by making nanocomposite preparation of curcumin with metal oxide nanoparticles, poly lactic-co-glycolic acid (PLGA) nanoparticles and solid lipid nanoparticles that increases its bioavailability in the tissue. KEY FINDINGS: Curcumin has manifold therapeutic effects which include antidiabetic, antihypertensive, anticancer, anti-inflammatory and antimicrobial properties...
October 17, 2016: Journal of Pharmacy and Pharmacology
Chi K Tang, Abhay Vaze, Min Shen, James F Rusling
Microchip-based microfluidic electrochemical arrays hold great promise for fast, high-throughput multiplexed detection of cancer biomarker proteins at low cost per assay using relatively simple instrumentation. Here we describe an inexpensive high-throughput electrochemical array featuring 32 individually addressable microelectrodes that is further multiplexed with an 8-port manifold to provide 256 sensors. The gold electrode arrays were fabricated by wet-etching commercial gold compact discs (CD-R) followed by patterned insulation...
August 26, 2016: ACS Sensors
Thomas J Hinton, Andrew Hudson, Kira Pusch, Andrew Lee, Adam W Feinberg
Polydimethylsiloxane (PDMS) elastomer is used in a wide range of biomaterial applications including microfluidics, cell culture substrates, flexible electronics, and medical devices. However, it has proved challenging to 3D print PDMS in complex structures due to its low elastic modulus and need for support during the printing process. Here we demonstrate the 3D printing of hydrophobic PDMS prepolymer resins within a hydrophilic Carbopol gel support via freeform reversible embedding (FRE). In the FRE printing process, the Carbopol support acts as a Bingham plastic that yields and fluidizes when the syringe tip of the 3D printer moves through it, but acts as a solid for the PDMS extruded within it...
October 10, 2016: ACS Biomaterials Science & Engineering
R N Makroo, Soma Agrawal, Mohit Chowdhry, Brinda Kakkar, Uday K Thakur
BACKGROUND: Liver transplantation is one of the solid organs most commonly being transplanted across the world. The indications, affordability and accessibility have grown manifold. To increase the donor pool, inclusion of ABO incompatible liver donors is being considered. To enhance the graft functioning and survival, immunoadsorption apheresis to reduce the ABO hemagglutination titres are on the rise. CASE REPORT: We report three cases ABO incompatible liver transplantation with immunoadsorption protocol...
September 28, 2016: Transfusion and Apheresis Science
Sébastien Renaux-Petel, Krzysztof Turzyński
We show the existence of a general mechanism by which heavy scalar fields can be destabilized during inflation, relying on the fact that the curvature of the field space manifold can dominate the stabilizing force from the potential and destabilize inflationary trajectories. We describe a simple and rather universal setup in which higher-order operators suppressed by a large energy scale trigger this instability. This phenomenon can prematurely end inflation, thereby leading to important observational consequences and sometimes excluding models that would otherwise perfectly fit the data...
September 30, 2016: Physical Review Letters
Oleksandr Kyriienko, Anders S Sørensen
We propose a microwave frequency single-photon transistor which can operate under continuous wave probing and represents an efficient single microwave photon detector. It can be realized using an impedance matched system of a three level artificial ladder-type atom coupled to two microwave cavities connected to input-output waveguides. Using a classical drive on the upper transition, we find parameter space where a single photon control pulse incident on one of the cavities can be fully absorbed into hybridized excited states...
September 30, 2016: Physical Review Letters
Pol Cirujeda, Yashin Dicente Cid, Henning Muller, Daniel Rubin, Todd A Aguilera, Billy W Loo, Maximilian Diehn, Xavier Binefa, Adrien Depeursinge
This paper proposes a novel imaging biomarker of lung cancer relapse from 3-D texture analysis of CT images. Three-dimensional morphological nodular tissue properties are described in terms of 3-D Riesz-wavelets. The responses of the latter are aggregated within nodular regions by means of feature covariances, which leverage rich intra- and inter- variations of the feature space dimensions. When compared to the classical use of the average for feature aggregation, feature covariances preserve spatial co-variations between features...
July 18, 2016: IEEE Transactions on Medical Imaging
Stefano Martiniani, K Julian Schrenk, Jacob D Stevenson, David J Wales, Daan Frenkel
We propose an efficient Monte Carlo method for the computation of the volumes of high-dimensional bodies with arbitrary shape. We start with a region of known volume within the interior of the manifold and then use the multistate Bennett acceptance-ratio method to compute the dimensionless free-energy difference between a series of equilibrium simulations performed within this object. The method produces results that are in excellent agreement with thermodynamic integration, as well as a direct estimate of the associated statistical uncertainties...
September 2016: Physical Review. E
William L Czaplyski, Christina G Na, Erik J Alexanian
Intermolecular functionalizations of aliphatic C-H bonds offer unique strategies for the synthesis and late-stage derivatization of complex molecules, but the chemical space accessible remains limited. Herein, we report a transformation significantly expanding the chemotypes accessible via C-H functionalization. The C-H xanthylation proceeds in useful chemical yields with the substrate as the limiting reagent using blue LEDs and an easily prepared N-xanthylamide. The late-stage functionalizations of complex molecules occur with high levels of site selectivity, and a variety of common functionality is tolerated in the reaction...
October 14, 2016: Journal of the American Chemical Society
Ivano Alessandri, John R Lombardi
Dielectrics represent a new frontier for surface-enhanced Raman scattering. They can serve as either a complement or an alternative to conventional, metal-based SERS, offering key advantages in terms of low invasiveness, reproducibility, versatility, and recyclability. In comparison to metals, dielectric systems and, in particular, semiconductors are characterized by a much greater variety of parameters and properties that can be tailored to achieve enhanced Raman scattering or related effects. Light-trapping and subwavelength-focusing capabilities, morphology-dependent resonances, control of band gap and stoichiometry, size-dependent plasmons and excitons, and charge transfer from semiconductors to molecules and vice versa are a few examples of the manifold opportunities associated with the use of semiconductors as SERS-active materials...
October 14, 2016: Chemical Reviews
O I Afanas'eva, E A Pylaeva, E A Klesareva, A V Potekhina, S I Provatorov, M I Afanas'eva, T L Krasnikova, V P Masenko, T I Aref'eva, S N Pokrovsky
AIM: To study the role of lipoprotein(a) [Lp(a)] as a potential autoantigen causing the activation of immunocompetent cells in atherosclerosis. SUBJECTS AND METHODS: A total of 104 men with stable coronary artery (CA) disease and different degrees of progressive coronary atherosclerosis were examined. Clinical blood analysis was carried out and lymphocyte subpopulations (CD4+, Th1, Th17, and Treg) were determined using immunofluorescence and flow cytometry. In addition, the indicators of blood lipid composition, Lp(a), autoantibody (autoAb) titer to Lp(a), and low-density lipoproteins (LDL), and the lymphocyte activation marker sCD25 were also measured...
2016: Terapevticheskiĭ Arkhiv
Helena Pillich, Madhu Puri, Trinad Chakraborty
Listeria monocytogenes is a ubiquitously occurring gram-positive bacterium in the environment that causes listeriosis, one of the deadliest foodborne infections known today. It is a versatile facultative intracellular pathogen capable of growth within the host's cytosolic compartment. Following entry into the host cell, L. monocytogenes escapes from vacuolar compartments to the cytosol, where the bacterium begins a remarkable journey within the host cytoplasm, culminating in bacterial spread from cell to cell, to deeper tissues and organs...
September 21, 2016: Current Topics in Microbiology and Immunology
M Schädel-Höpfner, B Bickert, C Dumont, P Laier, R Meier, A Nusche, T Pillukat, H Rosenthal, R Schmitt, F Siemers, A Zach, M Jung
BACKGROUND: Scaphoid fractures represent the most common carpal fractures and are often problematic and frequently lead to nonunion with osteoarthritis and collapse of the wrist. The reasons for the nonunion are manifold. Therefore, the main goal of diagnosis and therapy of acute fractures is to achieve bony union and to restore the anatomic shape of the scaphoid. In the long run, only this can preserve the normal function of the wrist. METHODOLOGY: The given recommendations are based on the new S3-level guideline of the AWMF (Association of the Scientific Medical Societies)...
October 10, 2016: Der Orthopäde
Shibing Zhou, Zhenyuan Xu, Fei Liu
It is crucial to determine the optimal number of clusters for the clustering quality in cluster analysis. From the standpoint of sample geometry, two concepts, i.e., the sample clustering dispersion degree and the sample clustering synthesis degree, are defined, and a new clustering validity index is designed. Moreover, a method for determining the optimal number of clusters based on an agglomerative hierarchical clustering (AHC) algorithm is proposed. The new index and the method can evaluate the clustering results produced by the AHC and determine the optimal number of clusters for multiple types of datasets, such as linear, manifold, annular, and convex structures...
October 5, 2016: IEEE Transactions on Neural Networks and Learning Systems
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