Search results for "LOD"

Enzyme-Controlled Nanodevice for Acetylcholine-Triggered Cargo Delivery Based on Janus Au–Mesoporous Silica Nanoparticles

2017

[EN] This work reports a new gated nanodevice for acetylcholine-triggered cargo delivery. We prepared and characterized Janus Au-mesoporous silica nanoparticles functionalized with acetylcholinesterase on the Au face and with supramolecular b-cyclodextrin: benzimidazole inclusion complexes as caps on the mesoporous silica face. The nanodevice is able to selectively deliver the cargo in the presence of acetylcholine via enzyme-mediated acetylcholine hydrolysis, locally lowering the pH and opening the supramolecular gate. Given the key role played by ACh and its relation with Parkinson's disease and other nervous system diseases, we believe that these findings could help design new therapeuti…

Central pain processing in patients with shoulder pain : a review of the literature

2017

Background Shoulder pain is a common health problem in which changes in shoulder structure cannot always explain the patient's perceived pain. Central sensitization (CS) might play a role in a subgroup of these patients. Methods The literature was systematically reviewed to address the role of CS in patients with shoulder pain. Electronic databases PubMed and Web of Knowledge were searched for relevant studies. Results Eighteen full-text articles were included, methodological quality was scored, and information was extracted. Studies were clustered on those studying patients with musculoskeletal (MSK) shoulder pain and those studying patients with hemiplegic shoulder pain (HSP). In particul…

Artūrs Holitschers un viņa ceļojumu apraksti

2018

Šis bakalaura darbs apskata Artūra Holitschera ceļojumu aprakstus. Darba mērķis ir analizēt viņa biogrāfiju un ceļojumus tā laika sabiedrības un literatūras attīstības tendenču kontekstā. Pētījumā rezultātā tika secināts, ka Artūrs Holitschers ienesa nozīmīgu ieguldījumu 20. gadsimta ceļojumu aprakstos un aprakstīja ne tikai arhitektūru, plisētas un valstis, bet arī sociālās un politiskās problēmas. Kā arī ņemot par piemēru viņa darbus, tos var uzskatīt gan par reportāžām, gan par ceļojumu aprakstiem, gan par ceļvežiem. Tika konstatēts, ka ceļojumu literatūru var sadalīt divos virzienos: fikcionālie un nefikcionālie teksti.

Low temperature plasma treatment of monomolecular Langmuir-Blodgett films

1993

Abstract The structure of the surface layer of materials is usually quite different from the bulk. Detailed information about the surface structure is often not available. This, together with the complex nature of low temperature plasma treatment, hinders the investigations of plasma chemical processes on solid surfaces. Monomolecular Langmuir-Blodgett (LB) structures offer a unique opportunity to prepare model surfaces with known thickness and molecular architecture. From the data obtained, the depth of the Ar plasma influence on solid organic surfaces was estimated to be about 400–1000 A depending on the nature of the surface layer. An oxygen plasma penetrates deeper with a penetration li…

Phase composition of Fe-containing Langmuir-Blodgett layers after thermal treatment in a reactive atmosphere

1993

By the Langmuir-Blodgett technique, mono- and multilayers of ferric stearate were drawn onto silicon wafers. They were thermodesorbed in air at 250–300°C, and the layers formed in this way were found to consist of γ-FeOOH with defective stoichiometry. By heating in H2, the layers can be reduced to Fe2− and even to α-Fe. The latter is magnetically ordered and highly corrosion resistant. Chloride ions, however, induce fast corrosion. FeCl2, formed by this corrosion, is rather unstable and transforms to an Fe3+ phase. The high corrosion resistance of the metallic Fe layer is assumed to be due to its excellent homogeneity. The experiments were performed using XPS, AES, CEMS, and SEM.

CEMS/XPS study of iron stearate Langmuir-Blodgett layers

1991

Langmuir-Blodgett mono- and multilayers of ferric stearate have been formed on oxidized silicon wafers. Thermodesorption of these layers was investigated by conversion electron Mossbauer and photoelectron spectroscopy and some complementary methods. Heating of samples in air up to 523 K leads to a desorption of the fatty acid chains, while the ferric ions are left on the substrate surface. These ions do not cluster laterally like it was found for Cd ions. They form a rather homogeneous, closed oxidic layer. This well defined layer may be used afterwards for further studies of surface reactions as well as interface and intra-layer interactions. The surface iron ions were found to exhibit a r…

Host—Guest Interactions Involving Cyclodextrins: Useful Complementary Insights Achieved by Polarimetry.

2007

Abstract By means of simple polarimetry, we studied the binding abilities of native α-, β-, and γ-cyclodextrins toward a group of suitably chosen model guests. We were able to get reliable estimations of the binding constants K, spread over a wide range (from 3.7 to 12,300 M−1), allowing us to carry on interesting comparisons. A comprehensive discussion of polarimetric data, and in particular a detailed analysis of the variations ΔΘ of molar optical activities consequent to inclusion, offered us the opportunity to get useful insights into the structure and dynamic behavior of host–guest complexes.

Dual-emitting Langmuir-Blodgett film-based organic light-emitting diodes.

2010

Langmuir-Blodgett (LB) films containing alternating layers of the metallosurfactants bis(4,4'-tridecyl-2,2'-bipyridine)-(4,4'-dicarboxy-2,2'-bipyridine) ruthenium(II)-bis(chloride) (1) and bis[2-(2,4-difluorophenyl)pyridine](4,4'-dinonadecyl-2,2'-bipyridine)iridium(III) chloride (2) have been prepared. Langmuir monolayers at the air-water interface of 1 and 2 with different anions in the subphase have been characterized by pi-A compression isotherms and Brewster angle microscopy (BAM). The transferred LB films have been characterized by IR, UV-vis and emission spectroscopy, and atomic force microscopy (AFM). Electroluminescent devices formed by LB films containing alternating layers of thes…

Studio polarimetrico degli equilibri di inclusione tra ciclodestrine native ed opportuni guest modello alifatici e aromatici

Enantiomeric separation of chiral phenoxy acid herbicides by electrokinetic chromatography. Application to the determination of analyte-selector appa…

2001

The enantiomeric resolution of chiral phenoxy acid herbicides was performed by electrokinetic chromatography using a cyclodextrin as chiral pseudophase (CD-EKC). A systematic evaluation of several neutral and charged cyclodextrins was made. Among the cyclodextrins tested, (2-hydroxy)propyl beta-cyclodextrin (HP-beta-CD) was found to be the most appropriate for the enantioseparation of phenoxy acids. The influence of some experimental conditions, such as nature and pH of the background electrolyte, chiral selector concentration, and temperature, on the enantiomeric separation of phenoxy acids was also studied. The use of a 50 mM electrolyte solution in ammonium formate at pH 5 and a temperat…