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https://www.readbyqxmd.com/read/28343125/structural-modeling-of-human-organic-cation-transporters
#1
Tikam Chand Dakal, Rajender Kumar, Dindial Ramotar
Human organic cation transporters (hOCTs) belong to solute carriers (SLC) 22 family of membrane proteins that play a central role in transportation of chemotherapeutic drugs for several clinical and pathological conditions, including cancer and diabetes. These transporters mediate drug transport; however, the precise mechanism of drug-binding and transport by them is not fully uncovered yet, partly due to unavailability of any crystal structure record. In this work, we performed a multi-phasic approach to compute the 3D structural models of seven human organic cation transporters (hOCTs) starting from primary protein sequence...
March 18, 2017: Computational Biology and Chemistry
https://www.readbyqxmd.com/read/28342572/exploring-the-atomic-structure-of-1-8nm-monolayer-protected-gold-clusters-with-aberration-corrected-stem
#2
Jian Liu, Nan Jian, Isabel Ornelas, Alexander J Pattison, Tanja Lahtinen, Kirsi Salorinne, Hannu Häkkinen, Richard E Palmer
Monolayer-protected (MP) Au clusters present attractive quantum systems with a range of potential applications e.g. in catalysis. Knowledge of the atomic structure is needed to obtain a full understanding of their intriguing physical and chemical properties. Here we employed aberration-corrected scanning transmission electron microscopy (ac-STEM), combined with multislice simulations, to make a round-robin investigation of the atomic structure of chemically synthesised clusters with nominal composition Au144(SCH2CH2Ph)60 provided by two different research groups...
November 22, 2016: Ultramicroscopy
https://www.readbyqxmd.com/read/28340224/the-association-of-context-specific-sitting-time-and-physical-activity-intensity-to-working-memory-capacity-and-academic-achievement-in-young-adults
#3
Mireia Felez-Nobrega, Charles H Hillman, Eva Cirera, Anna Puig-Ribera
To examine combined associations between self-reported context-specific sitting time (ST) and physical activity (PA) with working memory capacity (WMC) and academic achievement in a sample of Spanish adults. Undergraduate students ( n = 371; 21 years ± 3 years, 44% female) were recruited from University of Vic-Central University of Catalonia. Participants completed a 54-item survey that assessed socio-demographic variables (e.g. age, gender, academic year), min/week of light (LPA), moderate (MPA) and vigorous (VPA) intensity PA (International Physical Activity Questionnaire), min/day of domain-specific ST (Last 7 days sedentary behavior questionnaire) and academic performance (grade point average)...
March 18, 2017: European Journal of Public Health
https://www.readbyqxmd.com/read/28339828/single-session-of-functional-electrical-stimulation-assisted-walking-produces-corticomotor-symmetry-changes-related-to-changes-in-poststroke-walking-mechanics
#4
Jacqueline A Palmer, HaoYuan Hsiao, Tamara Wright, Stuart A Binder-Macleod
Background: Recent research demonstrated that symmetry of corticomotor drive to paretic and nonparetic plantarflexor muscles are related to the biomechanical ankle moment strategy that individuals with chronic stroke used to achieve their greatest walking speeds. Rehabilitation strategies that promote corticomotor balance could potentially improve post-stroke walking mechanics and enhance functional ambulation. Objective: To 1) test the effectiveness of a single session of gait training using functional electrical stimulation (FES) to improve plantarflexor corticomotor symmetry and plantarflexion ankle moment symmetry and 2) determine if changes in corticomotor symmetry relate to changes in ankle moment symmetry within the session...
February 23, 2017: Physical Therapy
https://www.readbyqxmd.com/read/28339274/exact-model-of-vacancy-mediated-solute-transport-in-magnesium
#5
Ravi Agarwal, Dallas R Trinkle
Most substitutional solutes in solids diffuse via vacancies. However, widely used analytic models for diffusivity make uncontrolled approximations in the relations between atomic jump rates that reduce accuracy. Symmetry analysis of the hexagonal close packed crystal identifies more distinct vacancy transitions than prior models, and a Green function approach computes diffusivity exactly for solutes in magnesium. We find large differences for the solute drag of Al, Zn, and rare earth solutes, and improved diffusion activation energies-highlighting the need for exact analytic transport models...
March 10, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28339249/electric-control-of-dirac-quasiparticles-by-spin-orbit-torque-in-an-antiferromagnet
#6
L Šmejkal, J Železný, J Sinova, T Jungwirth
Spin orbitronics and Dirac quasiparticles are two fields of condensed matter physics initiated independently about a decade ago. Here we predict that Dirac quasiparticles can be controlled by the spin-orbit torque reorientation of the Néel vector in an antiferromagnet. Using CuMnAs as an example, we formulate symmetry criteria allowing for the coexistence of topological Dirac quasiparticles and Néel spin-orbit torques. We identify the nonsymmorphic crystal symmetry protection of Dirac band crossings whose on and off switching is mediated by the Néel vector reorientation...
March 10, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28339237/current-noise-from-a-magnetic-moment-in-a-helical-edge
#7
Jukka I Väyrynen, Leonid I Glazman
We calculate the two-terminal current noise generated by a magnetic moment coupled to a helical edge of a two-dimensional topological insulator. When the system is symmetric with respect to in-plane spin rotation, the noise is dominated by the Nyquist component even in the presence of a voltage bias V. The corresponding noise spectrum S(V,ω) is determined by a modified fluctuation-dissipation theorem with the differential conductance G(V,ω) in place of the linear one. The differential noise ∂S/∂V, commonly measured in experiments, is strongly dependent on frequency on a small scale τ_{K}^{-1}≪T set by the Korringa relaxation rate of the local moment...
March 10, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28339231/chiral-dark-sector
#8
Raymond T Co, Keisuke Harigaya, Yasunori Nomura
We present a simple and natural dark sector model in which dark matter particles arise as composite states of hidden strong dynamics and their stability is ensured by accidental symmetries. The model has only a few free parameters. In particular, the gauge symmetry of the model forbids the masses of dark quarks, and the confinement scale of the dynamics provides the unique mass scale of the model. The gauge group contains an Abelian symmetry U(1)_{D}, which couples the dark and standard model sectors through kinetic mixing...
March 10, 2017: Physical Review Letters
https://www.readbyqxmd.com/read/28338692/computational-design-of-self-assembling-cyclic-protein-homo-oligomers
#9
Jorge A Fallas, George Ueda, William Sheffler, Vanessa Nguyen, Dan E McNamara, Banumathi Sankaran, Jose Henrique Pereira, Fabio Parmeggiani, T J Brunette, Duilio Cascio, Todd R Yeates, Peter Zwart, David Baker
Self-assembling cyclic protein homo-oligomers play important roles in biology, and the ability to generate custom homo-oligomeric structures could enable new approaches to probe biological function. Here we report a general approach to design cyclic homo-oligomers that employs a new residue-pair-transform method to assess the designability of a protein-protein interface. This method is sufficiently rapid to enable the systematic enumeration of cyclically docked arrangements of a monomer followed by sequence design of the newly formed interfaces...
April 2017: Nature Chemistry
https://www.readbyqxmd.com/read/28338147/symmetry-breaking-during-nanocrystal-growth
#10
Kyle D Gilroy, Hsin-Chieh Peng, Xuan Yang, Aleksey Ruditskiy, Younan Xia
Symmetry breaking is a ubiquitous phenomenon that occurs spontaneously when a system is subjected to changes in size and/or variations in terms of thermodynamic parameters. As a stochastic process, even small fluctuations acting on a system can arbitrarily push it down one of the branches of a bifurcation. In this feature article, we use nanocrystal growth to illustrate the concept of symmetry breaking. Our aim is to convey its importance from a mechanistic perspective, by which one can rationally alter the experimental conditions to manipulate the growth pattern (symmetric vs...
March 24, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28337994/the-new-phases-due-to-symmetry-protected-piecewise-berry-phases-enhanced-pumping-and-non-reciprocity-in-trimer-lattices
#11
Xuele Liu, G S Agarwal
Finding new phase of matter is a fundamental task in physics. Generally, various phases or states of matter (for instance solid/liquid/gas phases) have different symmetries, the phase transitions among them can be explained by Landau's symmetry breaking theory. The topological phases discovered in recent years show that different phases may have the same symmetry. The different topological phases are characterized by different integer values of the Berry phases. By studying one dimensional (1D) trimer lattices we report new phases beyond topological phases...
March 24, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28337133/inferring-master-painters-esthetic-biases-from-the-statistics-of-portraits
#12
Hassan Aleem, Ivan Correa-Herran, Norberto M Grzywacz
The Processing Fluency Theory posits that the ease of sensory information processing in the brain facilitates esthetic pleasure. Accordingly, the theory would predict that master painters should display biases toward visual properties such as symmetry, balance, and moderate complexity. Have these biases been occurring and if so, have painters been optimizing these properties (fluency variables)? Here, we address these questions with statistics of portrait paintings from the Early Renaissance period. To do this, we first developed different computational measures for each of the aforementioned fluency variables...
2017: Frontiers in Human Neuroscience
https://www.readbyqxmd.com/read/28336837/pnma-bn-another-boron-nitride-polymorph-with-interesting-physical-properties
#13
Zhenyang Ma, Zheng Han, Xuhong Liu, Xinhai Yu, Dayun Wang, Yi Tian
Structural, mechanical, electronic properties, and stability of boron nitride (BN) in Pnma structure were studied using first-principles calculations by Cambridge Serial Total Energy Package (CASTEP) plane-wave code, and the calculations were performed with the local density approximation and generalized gradient approximation in the form of Perdew-Burke-Ernzerhof. This BN, called Pnma-BN, contains four boron atoms and four nitrogen atoms buckled through sp³-hybridized bonds in an orthorhombic symmetry unit cell with Space group of Pnma...
December 28, 2016: Nanomaterials
https://www.readbyqxmd.com/read/28336530/using-chiral-tactoids-as-optical-probes-to-study-the-aggregation-behavior-of-chromonics
#14
Karthik Nayani, Jinxin Fu, Rui Chang, Jung Ok Park, Mohan Srinivasarao
Tactoids are nuclei of an orientationally ordered nematic phase that emerge upon cooling the isotropic phase. In addition to providing a natural setting for exploring chromonics under confinement, we show that tactoids can also serve as optical probes to delineate the role of temperature and concentration in the aggregation behavior of chromonics. For high concentrations, we observe the commonly reported elongated bipolar tactoids. As the concentration is lowered, breaking of achiral symmetry in the director configuration is observed with a predominance of twisted bipolar tactoids...
March 23, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28336270/the-natural-history-of-cystic-echinococcosis-in-untreated-and-albendazole-treated-patients
#15
N Solomon, M Kachani, E Zeyhle, C N L Macpherson
The World Health Organization (WHO) treatment protocols for cystic echinococcosis (CE) are based on the standardized ultrasound (US) classification. This study examined whether the classification reflected the natural history of CE in untreated and albendazole-treated patients. Data were collected during mass US screenings in CE endemic regions among transhumant populations, the Turkana and Berber peoples of Kenya and Morocco. Cysts were classified using the WHO classification. Patient records occurring prior to treatment, and after albendazole administration, were selected...
March 20, 2017: Acta Tropica
https://www.readbyqxmd.com/read/28336256/nose-burns-4-dimensional-analysis
#16
J Bouguila, C Ho Quoc, R Viard, A Brun, D Voulliaume, J-P Comparin, J-L Foyatier
The nose is the central organ of the face. It has two essential roles, aesthetic and breathing. It is often seriously damaged in the context of facial burns, causing grotesque facial disfigurement. As this disfigurement is visible on frontal and profile views, the patient suffers both socially and psychologically. The nose is a three-dimensional organ. Reconstruction is therefore more difficult and needs to be more precise than in other parts of the face. Maintaining symmetry, contour and function are essential for successful nasal reconstruction...
March 20, 2017: European Annals of Otorhinolaryngology, Head and Neck Diseases
https://www.readbyqxmd.com/read/28334489/ce-iv-gd-iii-mixed-oxides-as-hosts-for-er-iii-based-upconversion-phosphors
#17
Cecilia Sorbello, Petra Gross, Cristian A Strassert, Matías Jobbágy, Beatriz C Barja
A family of Er(III) and Er(III) -Yb(III) based nanophosphors, hosted in monophasic oxidic Ce(IV) -Gd(III) binary solid solutions, was prepared. The samples were formulated with a constant Er(III) content as the activator, with the eventual addition of Yb(III) as a sensitizer. The amorphous Ce0.94-x Gdx Er0.06 (OH)CO3 ⋅H2 O and Ce0.94-x Gdx Er0.05 Yb0.01 (OH)CO3 ⋅H2 O precursors were prepared by following the urea method to obtain monodispersed spheres of tunable size ranging from 30 to 450 nm. After being decomposed at 1273 K under an atmosphere of air, the precursors of 200 nm in diameter evolved into monophasic polycrystalline particles preserving the parent shape and size...
March 23, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/28334327/autologous-vs-irradiated-homologous-costal-cartilage-as-graft-material-in-rhinoplasty
#18
Jee Hye Wee, Sue Jean Mun, Woo Sung Na, Heejin Kim, Joo Hyun Park, Dong-Kyu Kim, Hong-Ryul Jin
Importance: Studies comparing surgical results of rhinoplasty using autologous costal cartilage (ACC) and irradiated homologous costal cartilage (IHCC) are rare. Objectives: To compare the clinical results of major augmentation rhinoplasty using ACC vs IHCC and analyze the histologic properties of both types of cartilage. Design, Setting, and Participants: A retrospective clinical study was conducted among patients who had undergone rhinoseptoplasty using ACC or IHCC from January 1, 2009, to December 31, 2014...
March 23, 2017: JAMA Facial Plastic Surgery
https://www.readbyqxmd.com/read/28334152/repeated-and-diverse-losses-of-corolla-bilateral-symmetry-in-the-lamiaceae
#19
Jinshun Zhong, Jill C Preston, Lena C Hileman, Elizabeth A Kellogg
Background and Aims: Independent evolution of derived complex characters provides a unique opportunity to assess whether and how similar genetic changes correlate with morphological convergence. Bilaterally symmetrical corollas have evolved multiple times independently from radially symmetrical ancestors and likely represent adaptations to attract specific pollinators. On the other hand, losses of bilateral corolla symmetry have occurred sporadically in various groups, due to either modification of bilaterally symmetrical corollas in late development or early establishment of radial symmetry...
March 1, 2017: Annals of Botany
https://www.readbyqxmd.com/read/28333433/high-performance-complementary-transistors-and-medium-scale-integrated-circuits-based-on-carbon-nanotube-thin-films
#20
Zhiyong Zhang, Yingjun Yang, Li Ding, Jie Han, Lian-Mao Peng
Solution-derived carbon nanotube (CNT) network films with high semiconducting purity are suitable materials for the wafer-scale fabrication of field-effect transistors (FETs) and integrated circuits (ICs). However, it is challenging to realize high-performance complementary metal-oxide-semiconductor (CMOS) FETs with high yield and stability on such CNT network films, and this difficulty hinders the development of CNT-film-based ICs. In this work, we developed a doping-free process for the fabrication of CMOS FETs based on solution-processed CNT network films, in which the polarity of the FETs was controlled by using Sc or Pd as the source/drain contacts to selectively inject carriers into the channels...
March 23, 2017: ACS Nano
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