Search results for "table"
showing 10 items of 2807 documents
The importance of sedimenting organic matter, relative to oxygen and temperature, in structuring lake profundal macroinvertebrate assemblages
2012
We quantified the role of a main food resource, sedimenting organic matter (SOM), relative to oxygen (DO) and temperature (TEMP) in structuring profundal macroinvertebrate assemblages in boreal lakes. SOM from 26 basins of 11 Finnish lakes was analysed for quantity (sedimentation rates), quality (C:N:P stoichiometry) and origin (carbon stable isotopes, δ13C). Hypolimnetic oxygen and temperature were measured from each site during summer stratification. Partial canonical correspondence analysis (CCA) and partial regression analyses were used to quantify contributions of SOM, DO and TEMP to community composition and three macroinvertebrate metrics. The results suggested a major contribution o…
Fluoreszierende und nicht fluoreszierende (Aryl)(vinyl)sulfone — Reagenzien zum Schutz und Nachweis von Thiolfunktionen
1985
Konkurrenzversuche und kinetisch verfolgte Umsetzungen geben Aufschlus uber die Geschwindigkeit der Addition von primaren, sekundaren und tertiaren Thiolen an die (Aryl)- bzw. (Alkyl)-(vinyl)sulfone 1 und 4 – 7. Die gebildeten saurestabilen 2-(Alkyl-/arylthio)ethylsulfone werden durch Basen in einer der Bildung analogen Geschwindigkeitsabstufung wieder in die Thiole und Vinylsulfone zerlegt. Eine kinetisch gesteuerte, selektive Einfuhrung und selektive Ablosung unterschiedlicher Arylsulfonylethyl-Schutzgruppen in dem gleichen Molekul ist damit moglich. – Die Verwendung fluoreszierender Vinylsulfone (5, 10 und 11) eroffnet der Analyse und Synthese neue Einsatzfelder. Die SH-selektiven Vinyls…
(1aR,2aS,5aS,5bS)-Perhydro-4H-oxireno[3,4]cyclopenta[1,2-b]furan-4-one
2007
The structure of the title compound, C7H8O3, was determined in the course of our studies of the synthesis of cyclopenta[1,2-b]furan-4-one derivatives. The molecule has four chiral C atoms. The X-ray crystal structure analysis shows the compound to possess an epoxide group with an endo orientation with respect to the lactone group.
Methyl 3-(4-hydroxyphenyl)propionate
2018
The title compound, C10H12O3, crystallizes in the orthorhombicP212121space group. The structure contains a phenolic group with the OH being coplanar with the phenyl ring. The structure exhibits significant hydrogen bonding between the O—H group of one molecule and the CO group of an adjacent one. These O—H...O=C interactions form chains of molecules parallel to thebaxis. No π–π or C—H...π intermolecular interactions are observed.
Confocal Endomicroscopy Shows Food-Associated Changes in the Intestinal Mucosa of Patients With Irritable Bowel Syndrome
2014
Background & Aims We investigated suspected food intolerances in patients with irritable bowel syndrome (IBS) using confocal laser endomicroscopy (CLE) for real-time visualization of structural/functional changes in the intestinal mucosa after food challenge. Patients with functional changes after food challenge (CLE+) were placed on personalized exclusion diets and followed up for long-term symptom relief. Methods Thirty-six IBS patients with suspected food intolerance and 10 patients with Barrett's esophagus (controls) without IBS symptoms were examined by CLE at University Hospital Schleswig-Holstein (Kiel, Germany). Diluted food antigens were administered directly to the duodenal mucosa…
From Food Map to FODMAP in Irritable Bowel Sindrome.
2016
Irritable bowel syndrome (IBS) is one of the most common gastrointestinal diseases in the general population, with a prevalence ranging from 12 % to 30 %, mainly affecting younger patients (i.e., <50 years of age) and women [1]. As in other chronic functional gastrointestinal disorders, abdominal discomfort or pain, abnormal bowel habits, and often bloating and abdominal distension are the main clinical features. Their diagnosis is based on symptom patterns (i.e., the Rome III criteria), which also allow categorization in diarrhea-predominant (D-IBS), constipation-predominant (C-IBS), mixed diarrhea and constipation (M-IBS), and unclassified (U-IBS) IBS [2]. Symptom severity ranges from tol…
Trophic habits of Muscardinus avellanarius (Mammalia Gliridae) as revealed by multiple stable isotope analysis
2007
Multiple stable isotope analysis was used to investigate the diet of the common dormouse Muscardinus avellanarius in a mixed Mediterranean forest. δ13C and δ15N values of dormouse tissues compared to those of the vegetal and animal sources available in the area showed that the isotopic composition of both adult and juvenile M. avellanarius could be explained by a mixture of vegetal and animal organic matter. The isotopic composition of the assimilated nitrogen was mostly explained by the organic matter from flora. Among the vegetal components, flowers of Fagus silvatica, Quercus robur, and the rarer Crataegus oxyacantha, berries of Ilex aquifolium and acorns of Q. robur were found in the ad…
Water Adsorption Characteristics of Acyclic Oligosaccharides of α-Gluose Studied by Near Infrared Spectroscopy
2013
The adsorption properties of water molecules on maltooligosaccharides are attributed to the OH groups of the glucose rings in maltooligosaccharides. The water molecules are adsorbed onto OH groups by hydrogen bond formation. Near infrared spectroscopic and gravimetric techniques were used in analysing the adsorption characteristics of maltooligosaccharides. Near infrared spectra of the dry maltooligosaccharides were acquired during the adsorption of wa- ter molecules at a relative humidity of 50%. The amounts of water adsorbed by the samples were also recorded by an ana- lytical balance. Second derivative techniques were used in decomposing the OH combination frequency of the adsorbed water…
1,3-Di(hetero)aryl-7-substituted Pyrenes—An Undiscovered Area of Important Pyrene Derivatives
2019
Despite the pyrene derivatives have been covered extensively by scientists during the last years, many interesting properties and applications of pyrene derivatives have been presented, nowadays there are still areas of pyrenes’ chemistry that need to be fulfilled. Most of the described in literature pyrenes are 1,3,6,8-tetrasubstituted followed by 4,5,9,10-tetrasubstituted, 2,7-, and 1,6-, and 1,8-disubstituted pyrene derivatives. In the case of 1,3-di(hetero)aryl-7-substituted, there are only a few examples of derivatives containing at position 7 - tert-butyl group. In this work, the necessity of synthesis of 1,3-di(hetero)aryl-7-substituted pyrenes is presented based on the results of th…
4-Bromophenyl 2,4-dibromophenyl ether
2002
The title compound, C12H7Br3O, belongs to a group of flame retardants known as polybrominated diphenyl ethers (PBDE). Salient features of the packing of the title compound are infinite intermolecular Br⋯Br contact chains along the b direction.