Read by QxMD icon Read

Strong ion difference

Yan Peng, Tilmann Bodenstein, Karin Fink, Valeriu Mereacre, Christopher E Anson, Annie K Powell
The single ion magnetic properties of Co(ii) are affected by the details of the coordination geometry of the ion. Here we show that a geometry close to trigonal prismatic which arises when the ligand 6,6'-((1Z)-((piperazine-1,4-diylbis(propane-3,1-diyl))bis(azanylylidene))bis(methanylylidene))bis(2-methoxyphenol) coordinates to Co(ii) does indeed lead to enhanced single-ion behaviour as has previously been predicted. Synthesis of the compound, structural information, and static as well as dynamic magnetic data are presented along with an analysis using quantum chemical ab initio calculations...
October 25, 2016: Physical Chemistry Chemical Physics: PCCP
Jingyi Nie, Zhengke Wang, Qiaoling Hu
As one of the most important polysaccharide, chitosan (CS) has generated a great deal of interest for its desirable properties and wide applications. In the utilization of CS materials, hydrogel is a major and vital branch. CS has the ability to coordinate with many metal ions by a chelation mechanism. While most researchers focused on the applications of complexes between CS and metal ions, the complexes can also influence gelation process and structure of CS hydrogel. In the present work, such influence was studied with different metal ions, revealing two different kinds of mechanisms...
October 25, 2016: Scientific Reports
Taiping Qing, Xiaoxiao He, Dinggeng He, Zhihe Qing, Kemin Wang, Yanli Lei, Ting Liu, Peng Tang, Yue Li
In this work, we developed a simple, rapid and mild strategy for synthesis of DNA-templated fluorescent gold nanoclusters (AuNCs) through association of gold ions to DNA templates and reduction with 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES). After systematical investigation on the formation of fluorescent AuNCs by using different DNA templates, C5 DNA was found as the best template for the formation of fluorescent AuNCs in this system. This process could be completed within 5min after the reaction beginning under ambient conditions...
December 1, 2016: Talanta
Wei Fan, Yanyun Li, Qing Sun, Tengjiao Ma, Bing Fan
BACKGROUND: In infected periapical tissues, Enterococcus faecalis is one of the most common dominant bacteria. Chlorhexidine has been proved to show strong antibacterial ability against E. faecalis but is ineffective in promoting mineralization for tissues around root apex. Mesoporous calcium-silicate nanoparticles are newly synthesized biomaterials with excellent ability to promote mineralization and carry-release bioactive molecules in a controlled manner. In this study, mesoporous calcium-silicate nanoparticles were functionalized with chlorhexidine and their releasing profile, antibacterial ability, effect on cell proliferation and in vitro mineralization property were evaluated...
October 21, 2016: Journal of Nanobiotechnology
Debojit Bhattacharya, Suranjan Shil, Anirban Misra, Laimutis Bytautas, Douglas J Klein
Here we study a set of novel magnetic organic molecular species with different halide ions (fluoride, chloride, bromide) absorbed ~2Å above or below the center of an aromatic π-ring in an m-aminyl diradical. Focus is on the nature of anion-π interaction and its impact on magnetic properties, specifically on magnetic anisotropy and on intramolecular magnetic exchange coupling. In the development of single molecule magnets, magnetic anisotropy is considered to be the most influential factor. A new insight regarding the magnetic anisotropy which determines the barrier height for relaxation of magnetization of m-aminyl diradical-derived anionic complexes is obtained from calculations of the axial Zero-Field-Splitting (ZFS) parameter D...
October 20, 2016: Journal of Physical Chemistry. A
Samuel A Neymotin, Benjamin A Suter, Salvador Dura-Bernal, Gordon M G Shepherd, Michele Migliore, William W Lytton
Corticospinal neurons (SPI), thick-tufted pyramidal neurons in motor cortex layer 5B that project caudally via the medullary pyramids, display distinct class-specific electrophysiological properties in vitro: strong sag with hyperpolarization, lack of adaptation, and a nearly linear frequency-current (FI) relationship. We used our electrophysiological data to produce a pair of large archives of SPI neuron computer models in two model classes: 1. Detailed models with full reconstruction; 2. Simplified models with 6 compartments...
October 19, 2016: Journal of Neurophysiology
Yann Desfougères, Jean-Michel Poitou, Henri Wróblewski, Laure Béven
Spiralin is the most abundant protein of several species of spiroplasmas, helical, motile bacteria pathogenic for arthropods and plants. This amphiphilic protein is anchored to the outer face of the plasma membrane by a lipoylated N-terminal cysteine. Although spiroplasma pathogenicity in mammals is controversial, it was shown that spiralin is highly immunogenic and endowed with immunomodulatory activity. In this paper, we describe a high performance method for the purification of Spiroplasma melliferum spiralin under non-denaturing conditions...
October 12, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
P Sławuta, G Sapikowski, B Sobieraj
: Buffer systems of blood and tissues, which have the ability to bind with and give up hydrogen ions, participate in maintaining the acid-base balance (ABB) of the organism. According to the classic model, the system of carbonic acid and bicarbonates, where the first component serves the role of an acid and the second a base, determines plasma pH. The so-called Stewart model, which assumes that ions in blood serum can be separated into completely dissociated - nonbuffer and not dissociated - buffer ions which may give up or accept H+ions, also describes the ABB of the organism...
September 1, 2016: Polish Journal of Veterinary Sciences
Ting Yu, Guangnan Zhou, Xia Hu, Shuji Ye
Understanding the transport behavior of the cholesterol molecules within cell membrane is a key challenge in cell biology at present. Here, we applied sum frequency generation vibrational spectroscopy (SFG-VS) to characterize the transport and organization of the cholesterol in different kinds of planar solid-supported lipid bilayers by combining achiral and chiral-sensitive polarization measurements. This method allows us to distinguish cholesterol organizations in the tail to tail, head to tail, head to head, and side-by-side manners...
October 18, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Žakula Jelena, Korićanac Lela, Keta Otilija, Todorović Danijela, A P Cirrone Giuseppe, Romano Francesco, Cuttone Giacomo, Petrović Ivan, Ristić-Fira Aleksandra
BACKGROUND & OBJECTIVES: The main goal when treating malignancies with radiation is to deprive tumour cells of their reproductive potential. One approach is to induce tumour cell apoptosis. This study was conducted to evaluate the ability of carbon ions ( [12] C) to induce apoptosis and cell cycle arrest in human HTB140 melanoma cells. METHODS: In this in vitro study, human melanoma HTB140 cells were irradiated with the 62 MeV/n carbon ( [12] C) ion beam, having two different linear energy transfer (LET) values: 197 and 382 keV/μm...
May 2016: Indian Journal of Medical Research
Alexander von Weber, Scott L Anderson
Mass-selected Ptn(+) ion deposition in ultrahigh vacuum (UHV) was used to prepare a series of size-selected electrodes with Ptn (n ≤ 14) clusters supported on either glassy carbon (GC) or indium tin oxide (ITO). After characterization of the physical properties of the electrodes in UHV, an in situ method was used to study electrocatalytic activity for the oxygen reduction and ethanol oxidation reactions, without significant air exposure. For each reaction studied, there are similarities between the catalytic properties of Ptn-containing electrodes and those of nanoparticulate or bulk Pt electrodes, but there are also important differences that provide mechanistic insights...
October 17, 2016: Accounts of Chemical Research
Ashima Sharma, Monu Yadav, B Rajesh Kumar, P Sai Lakshman, Raju Iyenger, Gopinath Ramchandran
BACKGROUND: A major change in anesthesia practice as regards to intraoperative infusion therapy is the present requirement. Switching over to balanced fluids can substantially decrease the incidence of lactic acidosis and hyperchloremic acidosis. The deleterious effects of unbalanced fluids are more recognizable during major surgeries. We prospectively studied the influence of Sterofundin (SF) and Ringer lactate (RL) on acid-base changes, hemodynamics, and readiness for extubation during scoliosis surgery...
September 2016: Anesthesia, Essays and Researches
Luke J Higgins, Cristian A Marocico, Vasilios D Karanikolas, Alan P Bell, John J Gough, Graham P Murphy, Peter J Parbrook, A Louise Bradley
A range of seven different Ag plasmonic arrays formed using nanostructures of varying shape, size and gap were fabricated using helium-ion lithography (HIL) on an InGaN/GaN quantum well (QW) substrate. The influence of the array geometry on plasmon-enhanced Förster resonance energy transfer (FRET) from a single InGaN QW to a ∼80 nm layer of CdSe/ZnS quantum dots (QDs) embedded in a poly(methyl methacrylate) (PMMA) matrix is investigated. It is shown that the energy transfer efficiency is strongly dependent on the array properties and an efficiency of ∼51% is observed for a nanoring array...
October 14, 2016: Nanoscale
Peter B Karadakov, David L Cooper
Spin-coupled (SC) theory is used to obtain modern valence-bond (VB) descriptions of the electronic structures of local minimum and transition state geometries of three species that have been considered to exhibit homoconjugation and homoaromaticity: the homotropenylium ion, C8H9(+), the cyclohepatriene neutral ring, C7H7, and the 1,3-bishomotropenylium ion, C9H11(+). The resulting compact SC wavefunctions are of comparable quality to CASSCF constructions that are based on the same "N electrons in M orbitals" active spaces, but they are much easier to interpret directly...
October 14, 2016: Journal of Physical Chemistry. A
Ekaterina Darii, Sandra Alves, Yves Gimbert, Alain Perret, Jean-Claude Tabet
Non-covalent complexes (NCC) between hexose monophosphates (HexP) and arginine (R) were analyzed using ESI MS and MS/MS in negative mode under different (hard, HC and soft, SC) desolvation conditions. High resolution mass spectrometry (HRMS) revealed the presence of different ionic species, namely, homo- and heteromultimers of R and HexP. Deprotonated heterodimers and corresponding sodiated species were enhanced under HC likely due to a decrease in available charge number associated with the reduction of H(+)/Na(+) exchange...
September 26, 2016: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Tongtong Li, Baosheng Liu, Shaotong Duan, Mengmeng Cui
In this study, the fluorescence spectra of sarafloxacin (SAR) under different pH conditions were investigated to determine the structural changes due to protonation that result from change in pH. At pH < 1.02, SAR exists in the H3 L(2)(+) form for which the maximum fluorescence emission wavelength was about 455 nm. At pH 1.87-4.94, SAR exists in the H2 L(+) form in which H3 L(2)(+) loses one proton in the nitrogen molecule at the 1-position in the quinoline ring. Fluorescence intensity was strong and steady and the maximum emission wavelength was 458 nm...
October 10, 2016: Luminescence: the Journal of Biological and Chemical Luminescence
Yue Wu, Sebastian Henke, Gregor Kieslich, Inke Schwedler, Miaosen Yang, Duncan A X Fraser, Dermot O'Hare
Versatility in metal substitution is one of the key aspects of metal-organic framework (MOF) chemistry, allowing properties to be tuned in a rational way. As a result, it important to understand why MOF syntheses involving different metals arrive at or fail to produce the same topological outcome. Frequently, conditions are tuned by trial-and-error to make MOFs with different metal species. We ask: is it possible to adjust synthetic conditions in a systematic way in order to design routes to desired phases? We have used in situ X-ray powder diffraction to study the solvothermal formation of isostructural M2 (bdc)2 dabco (M=Zn, Co, Ni) pillared-paddlewheel MOFs in real time...
October 11, 2016: Angewandte Chemie
Cristina Emilia Chițu-Tișu, Ecaterina Constanța Barbu, Mihai Lazăr, Mihai Bojincă, Ana-Maria Tudor, Adriana Hristea, Adrian Octavian Abagiu, Daniela Adriana Ion, Anca Ioana Bădărău
BACKGROUND: The development of combination antiretroviral therapies (cART) represents a significant advance in the treatment of (human immunodeficiency virus) HIV infection. However, several studies report that a large percentage of individuals with HIV, particularly those receiving cART, present body composition differences compared with the general population. The aim of this study was to explore body composition differences by dual-energy X-ray absorptiometry (DEXA), among HIV-positive patients receiving cART, in comparison to healthy controls...
October 11, 2016: Acta Clinica Belgica
Thomas J P Hersbach, Vladislav A Mints, Federico Calle-Vallejo, Alexei I Yanson, Marc T M Koper
Cathodic corrosion is a phenomenon in which negatively polarized metal electrodes are degraded by cathodic etching and nanoparticle formation. Though these changes are dramatic and sometimes even visible by eye, the exact mechanisms underlying cathodic corrosion are still unclear. This work aims to improve the understanding of cathodic corrosion by studying its onset on rhodium and gold electrodes, which are subjected to various constant cathodic potentials in 10 M NaOH. After this polarization, the electrodes are studied using cyclic voltammetry and scanning electron microscopy, allowing a corrosion onset potential of -1...
September 15, 2016: Faraday Discussions
Lei Wang, Yi-Hong Qiu, Yanjun Zeng
As the sole output neurons in the retina, ganglion cells play significant roles in transforming visual information into spike trains, and then transmitting them to the higher visual centers. However, coding strategies that retinal ganglion cells (RGCs) adopt to accomplish these processes are not completely clear yet. To clarify these issues, we investigate the coding properties of three types of RGCs (repetitive spiking, tonic firing, and phasic firing) by two different measures (spike-rate and spike-latency)...
2016: Frontiers in Computational Neuroscience
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"