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https://www.readbyqxmd.com/read/28732283/deciphering-the-mechanism-of-interaction-of-edifenphos-with-calf-thymus-dna
#1
Ajaz Ahmad, Masood Ahmad
Edifenphos is an important organophosphate pesticide with many antifungal and anti-insecticidal properties but it may cause potential hazards to human health. In this work, we have tried to explore the binding mode of action and mechanism of edifenphos to calf thymus DNA (CT-DNA). Several experiments such as ultraviolet-visible absorption spectra and emission spectroscopy showed complex formation between edifenphos and CT-DNA and low binding constant values supporting groove binding mode. These results were further confirmed by circular dichroism (CD), CT-DNA melting studies, viscosity measurements, density functional theory and molecular docking...
July 13, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28732165/complexity-reduction-in-large-quantum-systems-fragment-identification-and-population-analysis-via-a-local-optimized-minimal-basis
#2
Stephan Mohr, Michel Masella, Laura Elizabeth Ratcliff, Luigi Genovese
We present, within Kohn-Sham Density Functional Theory calculations, a quantitative method to identify and assess the partitioning of a large quantum mechanical system into fragments. We then show how within this framework simple generalizations of other well-known population analyses can be used to extract, from first principles, reliable electrostatic multipoles for the identified fragments. Our approach reduces arbitrariness in the fragmentation procedure, and enables the possibility to assess, quantitatively, whether the corresponding fragment multipoles can be interpreted as observable quantities associated to a system's moiety...
July 21, 2017: Journal of Chemical Theory and Computation
https://www.readbyqxmd.com/read/28731795/plant-size-and-competitive-dynamics-along-nutrient-gradients
#3
Deborah E Goldberg, Jason P Martina, Kenneth J Elgersma, William S Currie
Resource competition theory in plants has focused largely on resource acquisition traits that are independent of size, such as traits of individual leaves or roots or proportional allocation to different functions. However, plants also differ in maximum potential size, which could outweigh differences in module-level traits. We used a community ecosystem model called mondrian to investigate whether larger size inevitably increases competitive ability and how size interacts with nitrogen supply. Contrary to the conventional wisdom that bigger is better, we found that invader success and competitive ability are unimodal functions of maximum potential size, such that plants that are too large (or too small) are disproportionately suppressed by competition...
August 2017: American Naturalist
https://www.readbyqxmd.com/read/28731706/automated-construction-of-molecular-active-spaces-from-atomic-valence-orbitals
#4
Elvira R Sayfutyarova, Qiming Sun, Garnet Kin-Lic Chan, Gerald Knizia
We introduce the atomic valence active space (AVAS), a simple and well-defined automated technique for constructing active orbital spaces for use in multi-configuration and multi-reference (MR) electronic structure calculations. Concretely, the technique constructs active molecular orbitals capable of describing all relevant electronic configurations emerging from a targeted set of atomic valence orbitals (e.g., the metal d orbitals in a redcoordination complex). This is achieved via a linear transformation of the occupied and unoccupied orbital spaces from an easily obtainable single-reference wavefunction (such as from a Hartree-Fock or Kohn-Sham calculations) based on projectors to targeted atomic valence orbitals...
July 21, 2017: Journal of Chemical Theory and Computation
https://www.readbyqxmd.com/read/28731109/the-preference-for-dual-gold-i-catalysis-in-the-hydro-alkoxylation-vs-phenoxylation-of-alkynes
#5
Èric Casals-Cruañas, Oscar F González-Belman, Pau Besalú-Sala, David J Nelson, Albert Poater
Dinuclear gold complexes and their use in catalysis have received significant recent attention, but there are few critical comparisons of mono- versus dual gold-catalysed pathways. Herein we study the hydroalkoxylation and hydrophenoxylation of alkynes using density functional theory calculations, and compare two possible mechanisms that have been proposed previously on the basis of theoretical and experimental studies, which unravel different preferences because of both the nature of the alkyne and alcohol and the non-innocent role of the counter-anion of a dual gold based catalyst...
July 21, 2017: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/28731099/novel-phosphorescent-cationic-iridium-iii-complexes-with-o-carboranylation-on-the-ancillary-n-n-ligand
#6
Xiang Li, Yongheng Yin, Hong Yan, Changsheng Lu, Qiang Zhao
A novel series of heteroleptic iridium complexes with 2-phenyl-pyridine as a main ligand and carborane-functionalized 2,2'-bipyridine as an ancillary ligand were synthesized, and characterized as [Ir(ppy)2(By)]PF6 (where ppy is 2-phenyl-pyridine, By is 5-(2-R-Cb)-2,2'-bipyridine, R = H (2a), CH3 (2b), Ph (2c), iPr (2d) and iBu (2e), or By is 4-(2-R-Cb)-2,2'-bipyridine while R = H (3a), CH3 (3b), Ph (3c), iPr (3d) and iBu (3e), Cb = o-carboran-1-yl). The R groups and the substitution sites of carborane on the pyridine ring have caused differences in the emission properties of these complexes...
July 21, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28731081/metal-mediated-reactions-between-dialkylcyanamides-and-acetamidoxime-generate-unusual-nitrosoguanidinate-nickel-ii-complexes
#7
Zarina M Bikbaeva, Alexander S Novikov, Vitalii V Suslonov, Nadezhda A Bokach, Vadim Yu Kukushkin
The nitrosoguanidinate complexes [Ni{NH[double bond, length as m-dash]C(NR2)NN(O)}2] (R2 = Me21, (CH2)4O 2, (CH2)43, (CH2)54, (Me)Ph 5, Ph26, (p-MeC6H4)27) were obtained in low-to-moderate (12-26%) yields but reproducible yields in an unexpected metal-mediated reaction in MeOH between the nickel salt NiCl2·2H2O, N,N-disubstituted cyanamides NCNR2, and the amidoxime MeC([double bond, length as m-dash]NOH)NH2. These complexes were formed along with a spectrum of cyanamide-oxime coupling products. The IR and X-ray data indicate the delocalization within the NNO and NCN systems of the nitrosoguanidinate ligand...
July 21, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/28730755/the-unusual-role-of-the-aromatic-solvent-in-single-site-al-i-chemistry-insights-from-theory
#8
Shailja Jain, Kumar Vanka
The single site activation of strong σ bonds (such as that of H-H, P-H and N-H) remains a significant challenge in main group chemistry, with only a few cases reported to date. In this regard, recent exciting experiments done with Al(I) complexes hold significance, because they, too, have been seen to activate a variety of strong σ bonds. Such chemistry is generally seen to occur in aromatic solvents. The current computational studies with density functional theory (DFT) reveal the interesting reason for this: it is seen that an explicit aromatic solvent molecule acts as a catalyst by converting the Al(I) complex to Al(III) during the process...
July 21, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28729900/unravelling-functional-neurology-a-scoping-review-of-theories-and-clinical-applications-in-a-context-of-chiropractic-manual-therapy
#9
REVIEW
Anne-Laure Meyer, Amanda Meyer, Sarah Etherington, Charlotte Leboeuf-Yde
BACKGROUND: Functional Neurology (FN), a seemingly attractive treatment approach used by some chiropractors, proposes to have an effect on a multitude of conditions but some of its concepts are controversial. OBJECTIVES AND DESIGN: A scoping review was performed to describe, in the context of chiropractic manual therapy, 1) the FN theories, and 2) its clinical applications (i.e. its indications, examination procedures, treatment modalities, treatment plans, and clinical outcomes) using four sources: i) one key textbook, ii) the scientific peer-reviewed literature, iii) websites from chiropractors using FN, and iv) semi-structured interviews of chiropractors using FN...
2017: Chiropractic & Manual Therapies
https://www.readbyqxmd.com/read/28729850/drug-resistant-epilepsy-multiple-hypotheses-few-answers
#10
REVIEW
Fei Tang, Anika M S Hartz, Björn Bauer
Epilepsy is a common neurological disorder that affects over 70 million people worldwide. Despite the recent introduction of new antiseizure drugs (ASDs), about one-third of patients with epilepsy have seizures refractory to pharmacotherapy. Early identification of patients who will become refractory to ASDs could help direct such patients to appropriate non-pharmacological treatment, but the complexity in the temporal patterns of epilepsy could make such identification difficult. The target hypothesis and transporter hypothesis are the most cited theories trying to explain refractory epilepsy, but neither theory alone fully explains the neurobiological basis of pharmacoresistance...
2017: Frontiers in Neurology
https://www.readbyqxmd.com/read/28729844/not-merely-experiential-unconscious-thought-can-be-rational
#11
Katie E Garrison, Ian M Handley
Individuals often form more reasonable judgments from complex information after a period of distraction vs. deliberation. This phenomenon has been attributed to sophisticated unconscious thought during the distraction period that integrates and organizes the information (Unconscious Thought Theory; Dijksterhuis and Nordgren, 2006). Yet, other research suggests that experiential processes are strengthened during the distraction (relative to deliberation) period, accounting for the judgment and decision benefit...
2017: Frontiers in Psychology
https://www.readbyqxmd.com/read/28729843/is-a-transdisciplinary-theory-of-engagement-in-organized-settings-possible-a-concept-analysis-of-the-literature-on-employee-engagement-consumer-engagement-and-patient-engagement
#12
REVIEW
Guendalina Graffigna
Organizations are experiencing increased competition, disruptive innovation, and continuous changes in their social and economic context. Furthermore, the decrease of resources (economic and human) in such a demanding context make it imperative for organizations to find new models and strategies to make their service delivery more sustainable at the economic, environmental and psychological levels. In such a complex scenario the concept of engagement of the individuals involved in organized settings (either as service providers or as final receivers) is a promising lever for innovation...
2017: Frontiers in Psychology
https://www.readbyqxmd.com/read/28728857/-rosacea-new-data-for-better-care
#13
B Cribier
In the last 10 years, numerous studies have been published that throw new light on rosacea, in all areas of the disease. This overview summarises all the key developments, based on the indexed bibliography appearing in Medline between 2007 and 2017. Recent epidemiological data show that the prevalence of the disease is doubtless greater than estimated hitherto (more than 10% of adults in some countries) and that we should not overlook rosacea in subjects with skin phototypes V or VI, a condition that exists on all continents...
July 17, 2017: Annales de Dermatologie et de Vénéréologie
https://www.readbyqxmd.com/read/28727626/system-level-shared-governance-structures-and-processes-in-healthcare-systems-with-magnet%C3%A2-designated-hospitals-a-descriptive-study
#14
Carlisa M Underwood, Arlene N Hayne
OBJECTIVE: The purpose was to identify and describe structures and processes of best practices for system-level shared governance in healthcare systems. BACKGROUND: Currently, more than 64.6% of US community hospitals are part of a system. System chief nurse executives (SCNEs) are challenged to establish leadership structures and processes that effectively and efficiently disseminate best practices for patients and staff across complex organizations, geographically dispersed locations, and populations...
July 2017: Journal of Nursing Administration
https://www.readbyqxmd.com/read/28727547/designing-and-implementation-of-stable-sinusoidal-rough-neural-identifier
#15
Ghasem Ahmadi, Mohammad Teshnehlab
A rough neuron is defined as a pair of conventional neurons that are called the upper and lower bound neurons. In this paper, the sinusoidal rough-neural networks (SR-NNs) are used to identify the discrete dynamic nonlinear systems (DDNSs) with or without noise in series-parallel configuration. In the identification of periodic nonlinear systems, sinusoidal activation functions provide more efficient neural networks than the sigmoidal activation functions. Based on the Lyapunov stability theory, an online learning algorithm is developed to train the SR-NNs...
August 2017: IEEE Transactions on Neural Networks and Learning Systems
https://www.readbyqxmd.com/read/28727434/ellipsometry-of-colloidal-solutions-new-experimental-setup-and-application-to-metallic-colloids
#16
Yann Battie, Michel Stchakovsky, Aotmane En Naciri, Suzanna Akil, Nouari Chaoui, Laurent Broch
An ellipsometric cell is developed to simultaneously determine the shape distribution, the volume fraction, and the complex refractive index of gold and silver colloids. Simulation reveals that this cell drastically improves the detection limit of ellipsometry. Indeed, Ag and Au nanoparticles (NPs) are detected at the ppmv level. We demonstrate that the NPs shape distribution can be estimated from ellipsometric measurements by analyzing them with a shape distributed effective medium theory (SDEMT). The obtained distributions from ellipsometry are in agreement with those deduced from transmission electron microcopy (TEM)...
July 20, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28726931/electron-transfer-reactions-of-halogenated-electrophiles-a-different-look-into-the-nature-of-halogen-bonding
#17
Sergiy V Rosokha
The rates of oxidation of ferrocene derivatives by brominated molecules R-Br (CBr3CN, CBr4, CBr3NO2, CBr3COCBr3, CBr3CONH2, CBr3F, and CBr3H) were consistent with the predictions of the outer-sphere dissociative electron-transfer theory. The similar redox-reactions of the R-Br electrophiles with the typical halogen-bond acceptors tetramethyl-p-phenylenediamine (TMPD) or iodide were much faster than calculated using the same model. The fast redox-processes in these systems were related to the involvement of the transient halogen-bonded [R-Br, TMPD] or [R-Br, I(-)] complexes in which barriers for electron transfer were lowered by the strong electronic coupling of reactants...
July 20, 2017: Faraday Discussions
https://www.readbyqxmd.com/read/28726900/potential-energy-surface-stationary-points-and-dynamics-of-the-f-ch3i-double-inversion-mechanism
#18
Yong-Tao Ma, Xinyou Ma, Anyang Li, Hua Guo, Li Yang, Jiaxu Zhang, William L Hase
Direct dynamics simulations were performed to study the SN2 double inversion mechanism SN2-DI, with retention of configuration, for the F(-) + CH3I reaction. Previous simulations identified a transition state (TS) structure, i.e. TS0, for the SN2-DI mechanism, including a reaction path. However, intrinsic reaction coordinate (IRC) calculations from TS0 show it is a proton transfer (PT) TS connected to the F(-)HCH2I SN2 pre-reaction complex and the FHCH2I(-) proton transfer post-reaction complex. Inclusion of TS0 in the SN2-DI mechanism would thus involve non-IRC atomistic dynamics...
July 20, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28726873/local-decomposition-of-imaginary-polarizabilities-and-dispersion-coefficients
#19
Ignat Harczuk, Balazs Nagy, Frank Jensen, Olav Vahtras, Hans Ågren
We present a new way to compute the two-body contribution to the dispersion energy using ab initio theory. By combining the complex polarization propagator method and the LoProp transformation, local contributions to the Casimir-Polder interaction is obtained. The full dispersion energy in dimer systems consisting of pairs of molecules including H2, N2, CO, CH4, pyridine, and benzene is investigated, where anisotropic as well as isotropic models of dispersion are obtained using a decomposition scheme for the dipole-dipole polarizability...
July 20, 2017: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/28726745/dual-source-linear-energy-prediction-line-p-model-in-the-context-of-wsns
#20
Faisal Ahmed, Gert Tamberg, Yannick Le Moullec, Paul Annus
Energy harvesting technologies such as miniature power solar panels and micro wind turbines are increasingly used to help power wireless sensor network nodes. However, a major drawback of energy harvesting is its varying and intermittent characteristic, which can negatively affect the quality of service. This calls for careful design and operation of the nodes, possibly by means of, e.g., dynamic duty cycling and/or dynamic frequency and voltage scaling. In this context, various energy prediction models have been proposed in the literature; however, they are typically compute-intensive or only suitable for a single type of energy source...
July 20, 2017: Sensors
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