bluuebunny/crossref_metadata_2025 huggingface dataset:
Cyclometallierende Photodecarboxylierung von Übergangsmetallkomplexen
Authors: Pavlovski Valeri I. , Poznyak Anatoli L.
Published: September 2010

Photodecarboxylation reactions of chelated transition metal carboxylates leading to cyclometallated coordination compounds are considered. The possibilities of such reactions for the synthesis of compounds with three‐, four‐ or five‐membered metallocycles are demonstrated.
Die Reduktion von Bariumsulfat mit Kohlenstoff; Der Reaktionsverlauf
Authors: Kempe Gottfried , Bögel Monika , Meyer Gerhard
Published: September 2010

Barium sulphate is reduced by carbon to barium sulphide at higher temperatures. BaCO3, SO2, Sn and COS are found as by‐products in small amounts. It has been confirmed experimentally that barium sulphite is an intermediate of the reduction process. This compound, however, is not stable at temperatures above 500°C and decomposes mainly to BaSO4 and BaS and to a little extent to BaO and SO2. This reactions even take place in the presence of carbon which obviously only attacks the BaSO4 whilst the barium sulphide is enriched in the reaction products. A series of consecutive and side reactions is proposed describing the stepwise reduction of barium sulphate to barium sulphide.
Näherungsverfahren zur Ermittlung von Teilgeschwindigkeitskonstanten eines komplexen, linear abhängigen Reaktionsmodells
Authors: Füllbier Barbara , Haberland Detlef
Published: September 2010

A system of linear dependent competitive secondary reactions is regard to, for the kinetical investigation of the synthesis of dimethoate. An analytical solution of this simultane differential equation system is not possible. Various most integral methods of approximation for the solution of this problem are proposed and their usefulness are tested on the basis of experimental data. A complete solution of the differential equations, which is permitted to test the quality of the applied methods of approximations, are obtained by French‐transformation. A good correspondence between experimental and calculated data, is obtained by using a numerical procedure of Range‐Kutta.
Struktur und Aggregation von Dimethylammonium‐dimethylcarbamat (Dimcarb) und analogen Dialkylammonium‐dialkylcarbamaten
Authors: Schroth Werner , Schädler Hans‐Dieter , Andersch Jörg
Published: September 2010

In the wide range of carbamic acid derivatives, dialkylammonium‐dialkylcarbamates receive an exceptional position concerning their structure, molecular aggregation, and thermal behaviour. Among them the first member of this series, dimethylammonium‐dimethylcarbamate, briefly called dimcarb, represents a distillable liquid and claims additional interest in view of preparative utilizations. Its unusual properties have been investigated with regard to other ammonium‐carbamates, resulting in some remarkable conclusions by means of different physical methods. Thus, dimcarb is highly structured in dependence on temperature (viscosimetry, refractometry, cryoscopy). Dimethylamine and carbondioxide are bonded only weakly by binding energies in the order of non‐specific solvation energies (caloric measurements). The ionic species are predominantly involved in contact ion pairs (conductivity) and display a dynamic behaviour along with different prototropic interactions including dimethylcarbamic acid (N M R spectra). Informations about favoured structure combinations are given (quantum chemical calculations, I R and Raman spectra, mass spectra). Altogether, the unusual properties of dimcarb are based on a flexible structure behaviour, sensitively influenced by external factors (temperature, medium, reaction partners).
Rotationsbarrieren exocyclischer, partieller C,N‐Doppelbindungen in aromatischen Verbindungen — Indikatoren der n,π‐Mesomerie
Authors: Kleinpeter Erich
Published: September 2010

The rotational barriers about the exocyclic partial C,N‐double bonds of dimethylamino‐substituted aromatic π‐electron systems, studied so far, have been discussed with respect to the degree of n,π‐mesomerism of the dimethylamino substituent (n‐electrons) and the aromatic system (π‐electrons). Hereby, the possibility arises to estimate the π‐electron deficiency of the heteroaromatic systems studied if the dimethylamino substituent is hold constant. Relevant influences of steric hindrance, of heteroatoms involved, of one positive charge in the aromatic spezies, of further substituents on the same ring system and of the solvent on the dynamic process studied were considered. The parallelism of the rotational barriers to other useful parameters to classify the present degree of n,π‐mesomerisms (1H, 13C and 15N chemical shifts, Hammett substituent constants. C,H coupling constants) is critically estimated.

Additionally, special barrier (and adequately the chemistry) determining substructures (vinylogous amides and thioamides, tri‐ and pentamethine cyanines) could be identified.
Aktuelle Aufgaben der chemischen Toxikologie bei der Chemikalienbewertung
Authors: Titephan Ursula
Published: September 2010

The increasing of chemical products and chemical processes in the last years required new concepts for chemical safety. This new laws and governmental regulations based on the knowledge of the chemical, physical and toxicological properties of substances. In the field of safetycodes the chemical toxicology takes a leading part. The risk assessment includes knowledge about chemical reactivity, biotransformation, decomposition and accumulation in the biosphere and the migration of chemicals in water, air and/or soils. Knowledge about the behaviour of chemicals in the biosphere are necessarily for the replacement of toxic chemicals by nontoxic substances demanded by law of poisons or for the waste management. Some topics about the interdependence of progress of chemical toxicology and more chemical safety by laws are discussed.
Elektrochemisches Verhalten von 2,4‐Diamino‐1,3,5‐triazinen und ihren Photolyseprodukten
Authors: Schmidt Silke , Mattusch Jürgen , Werner Gerhard
Published: September 2010

2,4‐Diamino‐1,3,5‐triazines are widely applied as herbicides. These compounds are very stable which leads to a accumulation in soil and plants. To detect this group of compounds chromatographic methods (gas chromatography, HPLC, TLC) were employed in the past. The present work was done with the aim to determine electrochemically triazines in flowing systems like HPLC and FIA. Therefore the polarographic and voltammetric behaviour of these compounds was investigated. A sensitive detection was possible on a mercury electrode in the cathodic range and on a glassy carbon electrode pretreated by galvanostatic pulses in the anodic range. The sensitivity can be improved by photochemical derivatization of the triazines in 6‐position to create phenol‐like compounds. The photochemical response of simazine, prometryne, atrazine and ametryne depends on the substitutes in 2‐ and 4‐position and also in 6‐position. The degree of the photochemical conversion was measured with an amperometric detector in a FIA equipment.
Gifte sukkulenter Pflanzen: Cyanogene Glycoside, Glucosinolate, Amine
Authors: Swart Hans
Published: September 2010

Many of the about 10,000 succulents are cultivated in Botanical Gardens or amateur collections. Some of them are poisonous plants anl may cause health injuries by careless handling or misuse. Several succulents are used as medicinal, narcotic, or magic plants in their habitats, others are applied for fishing or making poisonous arrows for hunting. Poisoning of livestock may happen due to feeding of special succulents, too. This review mainly describes cyanogenic glycosides of the genus Adenia, glucosinolates in some Moringa species, and phenethylamines of the Cactaceae. As to await, further investigations in this field will get increasing importance, especially for the development of new drugs.
N‐Heterocyclen aus Diaminen
Authors: Kempter Gerhard , Spindler Jürgen
Published: September 2010

Pesticide chemistry has still a special importance for protection of human food; new pesticides to develop is necessary because of economical and ecological reasons. A description is given of the synthesis of numerous new heterocycles containing triazino‐, triazolino‐ and thiazolo‐condensed quinazolines, benzodiazepines and benzodiazocines. On principle, all of them are in possession of pesticide‐relevant structure elements like cyclic ureas and thioureas and allow correlations between ring‐size and bioactivity. The starting materials are o‐amino‐phenylalkylamines especially aromatic‐aliphatic 1,3‐, 1, 4‐and 1, 5‐diamines; their preparation is also given.
p‐Chinone und p‐Chinonfragmente; „Non‐innocent”︁‐Liganden in elektronenreichen Komplexen der späten d‐Elemente
Authors: Uhlig Egon
Published: September 2010

The coordination behaviour of p‐quinones and p‐quinone fragments in electron‐rich complexes is variable. Considering primarily the nickel triade elements, p‐quinones are bound to palladium(0) or platinum(0) by the CC‐groups (η2‐or η4‐interaction).

With nickel(0) the behavior is more complicated. η4(CC)‐coordination is found for Ni(Dch)2 and η2‐coordination for (dipy)Ni(Nch). But because of the stronger oxophilic properties of this element, also an η2(CO)‐coordination is possible, as was shown for (Cy3P)2Ni(Achθ•) · Et2O. In complexes with a low content of phosphine the donors R‐cum or Nch have the function of η2(CC, O)‐bridging ligands.

Chloranile with its high half‐wave potential oxidises nickel(0) to nickel(II) and is simultaneously reduced to the dianion of the corresponding hydroquinone. In another case — (Cy3P)Ni(Ach⊖) — the redox process stops at the state of nickel(I) and of the radical anion. It is a general rule, that both 1,5‐cyclooctadiene as a simple diolefine and normal p‐quinones can coordinate to nickel(0) or nickel(I) as n‐acceptor ligands by the CC‐ or in the case of Ach even by the CO‐group. This is not possible with nickel(II) which is only a weak †‐donor.

Tertiary phosphines attack Bch, CA, NCh or MSA nucleophilically forming phosphabetaines. Because of the lower nucleophilicity of the phosphine and the lower electrophilicity of the p‐quinone in the coordination sphere of electron‐rich central atoms this reaction does not proceed. The systems of (Cy3P)2Ni(C2H4) with CA, Bch and MSA are exceptional. In these cases the formation of phosphabetaines is connected with an one‐electron transfer. The products are nickel(II)‐species with radical anions as ligands.

In general the normal reactions of p‐quinones are hindered in the coordination sphere of electron‐rich complexes. But sometimes other pathways of synthetic use are opend.
Hexacoordinated Complexes of Phosphorus, Arsenic and Antimony Pentafluorides with Oxygen, Nitrogen and Sulphur Containing Ligands
Authors: Buslaev Yuryi , Ilyin Evgenyi , Calov Ursula
Published: September 2010

The paper considers complex formation and structure of phosphorus, arsenic and antimony fluorine‐containing octahedral compounds in organic solvents, aqueous and peroxide solutions, on the basis of results obtained by chemists of the USSR and G.D.R. in the course of recent year scientific cooperation.
Reaktionsverhalten der Kohlenhydrate in wasserfreiem, flüssigem Fluorwasserstoff
Authors: Miethchen Ralf
Published: September 2010

The present review discusses reactions of unprotected and protected carbohydrates in hydrogen fluoride as well as the synthesis of fluorinated carbohydrates by use of anhydrous liquid hydrogen fluoride or Systems containing hydrogen fluoride (e.g. HF/pyridine, triethylamine trishydrofluoride). Our results concerning the stereo‐selective synthesis of kinetically controlled glycosyl fluorides and the micellar aggregation of amphiphilic 3‐0‐(n‐alkyl)‐D‐gluco‐pyranose derivatives in HF are involved. The paper presents a brief introduction in a survey concerning the application of fluorinated carbohydrates. The literature published since the article of Lenard (1969) is summarized.
NMR‐Spektroskopie an phosphororganischen Verbindungen — Beiträge zur Molekülstruktur
Authors: Zschunke Adolf
Published: September 2010

The paper demonstrates the use of N M R‐spectroscopy of organic phosphorus compounds for the detailed description of the molecular structure in the liquid state. It gives special emphasis to the application of 31P‐coupling constants in solving stereochemical problems. An example is the estimation of the conformations and of the relative configuration of phosphorheterocycles.

The N M R‐detection of intramolecular mobility is demonstrated on Berry process of (CHs)2N P F4, bond‐fluctuation of Li3P7, phosphorus‐inversion of 1,3‐diphosphorheterocycles and simultaneous processes of allyl‐palladium‐phosphin‐complexes. The autoassociation of organo‐phosphides in different solvents is finally investigated by means of N M R‐spectroscopy.
Nichtklassische Kettenreaktionen
Authors: Eggert Lutz , Kuz'min Michail Georgievič , Ivanov Vladimir Leonidovič
Published: September 2010

The review considers non‐classical mechanisms of chain reactions, which were proposed in recent years. In contrary to classical radical chain mechanisms such mechanisms include electron transfer, heterolytic and other non‐heterolytic elementary propagation steps and a variety of transients (ions, ion‐radicals, biradicals etc.). Most of the known non‐classical chain reactions include electron transfer propagation step. A lot of new speculative chain mechanisms was proposed in literature, but further experimental investigations of short living transient and kinetics of these reactions is necessary to prove their mechanisms. Such investigations will open new possibilities to use chain reactions in chemical and other processes.
Koordinationschemische Stabilisierung „nackter”︁ Elemente der V. Hauptgruppe (außer Stickstoff) — Synthese, Struktur und Bindung
Authors: Scheer Manfred , Herrmann Eckhard
Published: September 2010

The complexchemisty of “nacked” Ex‐unites (E = P, As, Sb, Bi; x = 1–6) has developed rapidly since the end of the seventies. Most of the Ex‐groups, except P4, are unstable in the free state but can be stabilized by complexation with transition metal fragments. They are isolobal to the corresponding (CH)x‐arrangements. This article gives a comprehensive review of this young and dynamic field of chemistry up to 1988. It generalizes methods of synthesis, compares modes of coordination and types of polyeders of these complexes. The article describes the analogies and differences in the coordination behaviour of “nacked” Ex‐groups of phosphorus, arsenic, antimony and bismuth. Thus, there is an anomaly of bismuthine complexes by reason of the metallic character of Bi.
Zur Bestimmung der Grenzflächenspannung Salzhydratschmelze‐Halogenkohlenwasserstoff von „Galisol”︁‐Latentwärmespeicher‐Stoffkombinationen
Authors: Emons Hans‐heinz , Müller Armin , Naumann Rüdiger
Published: September 2010

The characterization of „Galisol”︁‐heat storage units requires the determination of interfacial tension between the heat storage material (salt hydrate) and the heat transfer liquid (halogened hydrocarbon). Hence, an apparatus was developed to investigate this interfacial tension under „Galisol”︁ ‐conditions (working temperature, pressure higher than 0, 1 MPa). The apparatus based on the pendant drop method. The interfacial tension in the system Na2SO4‐H2O‐n‐alkylsulphate‐C2H5Br was investigated as a function of the concentration of the surfactant and the time to adjust the equilibrium of the surfactant at the interface. The typical behaviour of the interfacial tension as a function of surfactant concentration in the investigated system can be observed. The cmc was found at 0,025% surfactant.
A Survey of Electrodes used for Voltammetric Analysis
Authors: Bond Alan M. , Scholz Fritz
Published: September 2010

This review describes the properties of the most common electrodes used for voltammetric analysis. Electrode construction and electrode materials are discussed as are applications under various conditions, such as aqueous and nonaqueous solvents, unstirred and flowing solutions. Less common electrodes are also discussed when a broader applicability in the field of analytical chemistry can be expected in the future. This review is intended to assist the analyst in choosing the appropriate electrode for a particular problem.
IR‐Spektroskopie mit Polarisierter Strahlung
Authors: Jordanov Bojidar
Published: September 2010

IR spectroscopic polarization methods for studying linear and circular dichroism, linear and circular birefringence are considered. A special attention is paid to the differential measurement of these phenomena by means of dispersive and FTIR spectrometers. Specific examples obtained by FTIR technique are presented.
Tandem‐Massenspektrometrie — Grundlagen und Applikationen
Authors: Stach Joachim , Möder Monika , Herzschuh Rainer
Published: September 2010

The fragmentation of metastable and collisionally activated ions as well as different experimental techniques which can be used to record daughter, parent and neutral loss spectra are discussed in the first part of this review. Advanced MS/MS methods are represented by the Neutralization Reionisation Mass Spectrometry (NRMS) which allows the characterization of neutral species and the angular resolution of the ion beam emerging from a collision cell, lending to Angle Resolved Mass Spectrometry (ARMS).

Typical applications of the tandem mass spectrometry are given by the determination of ion structures, the gas phase reactions of ions and the analysis of compounds in complex mixtures.
Lignin – Biosynthese, Struktur, Biodegradation
Authors: Härtig Ciaus , Meyer Dietrich , Fischer Klaus
Published: September 2010

Lignin is the second abundant natural material on the earth and get increasing importance as a compartment of renewable lignocelluloses. Based on a survey biosynthesis, structure, and biodegradation of lignin is under consideration. The known facts about biosynthesis and the newer results about mechanisms in biodegradation show some remarkable common features. In both cases there are enzymatic and nonenzymatic catalyzed reactions, the latter with radicalic character. In this connection several peroxidases play an important role.
Die Natur der Protein–Protein‐Wechselwirkung und ihr spektroskopischer Nachweis, dargestellt am Beispiel der Polyglycin–Insulin‐Aggregate
Authors: Mehlhorn Achim , Herzog Klaus , Noack Heike , Losse Günter
Published: September 2010

Weak intermolecular interactions between proteins may lead to mutual adaption of their secondary structures with the consequence of modified bioactivities. The basic possibilities of protein‐protein interactions are summarized in the light of their quantumchemically elucidated nature as well as their spectroscopic indications including modern mathematical tools for artficial resolution enhancement. In this way a clear differentiation between a mixture of proteins and their definite aggregates (complexes) becomes feasible. The example of insulin‐polyglycine mixtures and complexes is used to demonstrate scope and limitations of the FT‐IR spectroscopy in recognizing and interpreting protein‐protein interactions.
β-Phase Morphology in Ordered Poly(9,9-dioctylfluorene) Nanopillars by Template Wetting Method
Authors: Palacios R , Formentin P , Martinez-Ferrero E , Pallarès J , Marsal LF
Published: September 2010

An efficient method based in template wetting is applied for fabrication of ordered Poly(9,9-dioctylfluorene) (PFO) nanopillars with β-phase morphology. In this process, nanoporous alumina obtained by anodization process is used as template. PFO nanostructures are prepared under ambient conditions via infiltration of the polymeric solution into the pores of the alumina with an average pore diameter of 225 nm and a pore depth of 500 nm. The geometric features of the resulting structures are characterized with environmental scanning electron microscopy (ESEM), luminescence fluorimeter (PL) and micro μ-X-ray diffractometer (μ-XRD). The characterization demonstrates the β-phase of the PFO in the nanopillars fabricated. Furthermore, the PFO nanopillars are characterized by Raman spectroscopy to study the polymer conformation. These ordered nanostructures can be used in optoelectronic applications such as polymer light-emitting diodes, sensors and organic solar cells.
Liquid Chromatography–Light Scattering Detector–Mass Spectrometric Analysis of Digested Oxidized Rapeseed Oil
Authors: Tarvainen Marko , Suomela Jukka‐Pekka , Kuksis Arnis , Kallio Heikki
Published: September 2010

Rapeseed oil was oxidized chemically and thermally to produce two distinct oxidized oils. These oils, along with unoxidized oils, were subjected to an artificial digestion model to simulate the digestive processes in humans. Lipid digestion involves lipases that break down the intact triacylglycerol (TAG) molecules first to diacylglycerols, and eventually to sn‐2‐monoacylglycerols (MAG) and free fatty acids. A high performance liquid chromatography‐evaporative light scattering detector‐electrospray ionization‐mass spectrometric (HPLC–ELSD–ESI–MS) method was developed to monitor the lipolysis and the presence of oxidized lipids. The HPLC–ELSD–ESI–MS analysis enabled the separation and detection of nearly all the lipid species present in the sample after TAG hydrolysis. The HPLC–MS analyses of digestion products revealed that oxidized triacylglycerols are hydrolyzed by the digestive enzymes in a manner similar to that of native, unoxidized molecules. Significant amounts of sn‐1(3)‐MAG were found in all the samples after lipolysis, however, more of these were found in unoxidized rapeseed oil samples than in the oxidized oils. Several oxidized molecules were identified with the aid of synthesized oxylipids. This novel method is scalable to small‐scale preparative fractionation of oxidized lipid molecules from a complex digestion sample. Also, the fingerprint‐like, diagnostic, MS profiles of oxidized oils, reference compounds, and digestion products may be a great aid in comprehensive analysis of lipid oxidation and lipolysis.
Selectively Functionalized Glycerol/Diacid Dendrimers via Click Chemistry of Azido Fatty Acids
Authors: Zerkowski Jonathan A. , Nuñez Alberto , Solaiman Daniel K. Y.
Published: September 2010

Dendrimers consisting of glycerol and dicarboxylic acid units were synthesized using a convergent or “outside‐in” strategy. The multimeric arms, or dendrons, are joined to a central core in the final step using the azide/alkyne click reaction. The combination of these approaches allows the preparation of dendrimers with variable and controlled degrees of substitution at their periphery. For example, a single protected amino acid has been situated at the periphery, with all other substituents being hydrophobic. In another example, all the peripheral substituents are protected amino acids. The identity of the dendrimers is unambiguous due to the purification and characterization of all the synthetic intermediates. Functional groups have also been selectively incorporated along the arms (dicarboxylic acids) and at the cores.
Distribution of Triacylglycerols and Fatty Acids in Soybean Oil with Thermal Oxidation and Methylene Blue Photosensitization
Authors: Park Young Woo , Jeong Min Kyu , Park ChanUk , Lee JaeHwan
Published: September 2010

Profiles of triacylglycerols (TAG) and fatty acids were compared in soybean oil thermally oxidized at 180 °C for 60 min or methylene blue photosensitized for 10 h. Headspace oxygen in thermally oxidized and photosensitized soybean oil decreased significantly (p < 0.05) as oxidation time increased. Relative contents of linoleic and linolenic acids decreased and those of oleic acid increased during oxidation. In both thermal and photosensitized oxidation, TAG with lower than 44 equivalent carbon number including dilinoleoyllinolenoylglycerol (LLLn, 40), trilinolein (LLL, 42), oleoyllinoleoyllinolenoylglycerol (OLLn, 42), dilinoleoyloleoylglycerol (LLO, 44), and dilinoleoylpalmitoylglycerol (PLL, 44) significantly decreased, while those with dioleoyllinoleoylglycerol (OOL, 46) increased significantly in relative peak areas (p < 0.05). Photosensitized oxidation decreased TAG containing linoleic and linolenic acids significantly faster than thermal oxidation in soybean oil (p < 0.05), which may be due to the singlet oxygen reaction. Photosensitized soybean oils can be differentiated from thermally oxidized samples using the distributions of TAG by principal component analysis.
Continuity of the blow-up profile with respect to initial data and to the blow-up point for a semilinear heat equation
Authors: Zaag H. , Khenissy S. , Rébaï Y.
Published: September 2010

We consider blow-up solutions for semilinear heat equations with Sobolev subcritical power nonlinearity. Given a blow-up point

\hat a

, we have from earlier literature, the asymptotic behavior in similarity variables. Our aim is to discuss the stability of that behavior, with respect to perturbations in the blow-up point and in initial data. Introducing the notion of “profile order”, we show that it is upper semicontinuous, and continuous only at points where it is a local minimum.

Nous considérons des solutions explosives de l'équation semilinéaire de la chaleur avec une nonlinéarité sous-critique au sens de Sobolev. Etant donné un point d'explosion

\hat a

, grâce à des travaux antérieurs, on connaît le comportement asymptotique des solutions en variables auto-similaires. Notre objectif est de discuter la stabilité de ce comportement, par rapport à des perturbations du point d'explosion et de la donnée initiale. Introduisant la notion de « l'ordre du profil », nous montrons qu'il est semi-continu supérieurement, et continu uniquement aux points où il est un minimum local.
Imaging of Ulnar-Sided Wrist Pain
Authors: Porteous Rory , Harish Srinivasan , Parasu Naveen
Published: September 2010

Pain on the ulnar side of the wrist is a complex diagnostic dilemma. This is mainly due to the small size and complexity of the anatomical structures. The issue is compounded by the occurrence of positive imaging findings that are clinically asymptomatic. This pictorial essay deals with the imaging manifestations of different causes of ulnar-sided wrist pain.
The Canadian Association of Radiologists Guidelines for the Prevention of Contrast-induced Nephropathy: A Critical Appraisal
Authors: Lepanto Luigi , Tang An , Murphy-Lavallée Jessica , Billiard Jean-Sébastien
Published: September 2010

Objective

The purpose of this study is to critically appraise the Canadian Association of Radiologists (CAR) guidelines on the prevention of contrast-induced nephropathy (CIN).

Methods

The Appraisal of Guidelines Research and Evaluation (AGREE) tool is a questionnaire that consists of 23 key items organized in 6 domains (scope and purpose, stakeholder involvement, rigor of development, clarity and presentation, applicability, editorial independence). Four radiologists read the guidelines and completed the questionnaire independently. To assess the quality of the evidence, the articles listed in the bibliography were reviewed, and the following data were collected and tabulated: the type of contrast, the administration route, and the level of evidence (Centre for Evidence Based Medicine, University of Oxford).

Results

The highest score was for scope and purpose (92%), whereas the lowest scores were for rigor of development (50%) and applicability (40%). The score for the remaining domains were the following: stakeholder involvement (59%), clarity and presentation (69%), and editorial independence (63%). Although the bibliography of the CAR guidelines list 46 articles, only 33 were deemed pertinent to support the recommendations related to risk stratification or risk reduction of CIN. Only 3 articles dealt specifically with intravenous injection of iodinated contrast. Four articles dealt with ionic contrast, and, in 17 references, the contrast type was not specified. The best evidence (level 1) was in support of risk-reduction recommendations, but, in 8 of the 9 articles cited, the route of administration studied was exclusively intra-arterial.

Conclusion

It would be appropriate to revisit the topic of CIN and formulate new guidelines. A formal systematic review of the literature should be undertaken and the data extraction should specifically address contrast type and route of administration, as well as the applicability of any recommendations.
Patulous eustachian tube in bariatric surgery patients
Authors: Muñoz Daniel , Aedo Cristian , Der Carolina
Published: September 2010

OBJECTIVE

Patulous eustachian tube (PET) is associated with several factors, including weight loss. Rapid and significant weight loss in bariatric surgery patients may be risk factors for developing PET. The aim of this study is to provide information about the prevalence of PET after bariatric surgery and its association to weight loss.

STUDY DESIGN

Case series with planned data collection. SETTING: Tertiary center.

SUBJECTS AND METHODS

We recruited 163 patients who had undergone bariatric surgery at the Clinical Hospital of the University of Chile between 2006 and 2009. One hundred fortyone patients were finally analyzed by clinical interview and physical examination. Two groups were formed, with and without PET. The degree, time, and velocity of weight loss were compared between groups. Demographic information and clinical presentation are also presented.

RESULTS

The mean age was 38.9 years, and 76.6 percent of the patients were female. We found PET in 21.28 percent of the patients. Autophony was present in 96.6 percent of patients diagnosed with PET. Patients without PET experienced weight loss at an average of 39.54 kg during 16.59 months, while patients with PET experienced weight loss at an average of 48.63 kg in 12.11 months. The weight loss velocity in the PET group had a mean of 5.34 ±3.4 kg/month versus 2.98 ±1.3 kg/month in patients without PET. Time (P = 0.0037), magnitude (P = 0.0002), and velocity (P = 0.0005) of weight loss was higher in patients with PET.

CONCLUSION

Our case series shows a significant prevalence of PET in bariatric surgery patients, which has a correlation with weight loss velocity and magnitude.
The Role of Radiofrequency Ablation for Sacroiliac Joint Pain: A Meta‐Analysis
Authors: Aydin Steve M. , Gharibo Christopher G. , Mehnert Michael , Stitik Todd P.
Published: September 2010

Radiofrequency ablation (RFA) has become an option for those with chronic or refractory sacroiliac (SI) joint pain. The purpose of this critical review is to assess the existing literature and conduct a meta‐analysis to assess the effectiveness of RFA of the SI joint for pain relief at 3 and 6 months' after an RFA procedure. An electronic search of PubMed, OVID, Medline, and CINAHL were conducted with keywords; sacroiliac joint, sacroiliac pain, sacroiliac syndrome, sacroiliac radiofrequency ablation, sacroiliac neurolysis, sacroiliac injection, and low back pain. Articles that addressed RFA of the SI joint were reviewed. Ten articles ranging from inception to January 1, 2010, were found. The main outcome measure was a reduction of pain by ≥50% post‐RFA procedure. At 3 months, 7 groups met the criteria and at 6 months, 6 groups met the criteria. A meta‐analysis with a forest plot was done at the 3‐ and 6‐month patient follow‐up intervals. The associated standard error was calculated for each study group. An overall weighted average with respective standard error was also obtained. A calculation of 95% confidence intervals (95% CI) was then derived. A test for heterogeneity, publication bias, and file drawer effect was also done at the 3‐ and 6‐month intervals. At 3 months, a range of 0.538‐0.693 was found to have a 95% CI, with a pooled mean of 0.616. At 6 months, a 95% CI of 0.423‐0.576 was found, with a pooled mean of 0.499. The meta‐analysis demonstrated that RFA is an effective treatment for SI joint pain at 3 months and 6 months. This study is limited by the available literature and lack of randomized controlled trials. Further standardization of RFA lesion techniques needs to be established, coupled with prospective randomized controlled trials.
Joint Replacement and Hip Fracture Readmission Rates: Impact of Discharge Destination
Authors: Riggs Richard V. , Roberts Pamela S. , Aronow Harriet , Younan Tamer
Published: September 2010

Objective

To determine if discharge destination after hospitalization for hip replacement or repair influences the hospital readmission rate.

Design

A retrospective cohort study that included consecutive patients with a primary diagnosis of hip replacement or repair who were discharged from the acute hospital in a 3‐year period.

Setting

Urban academic nonprofit hospital.

Patients

Data for 606 orthopedic patients discharged alive from the acute hospital between January 2004 and September 2006 were abstracted from the University HealthSystem Consortium (UHC) Clinical DataBase/Resource Manager clinical database for the study hospital.

Main Outcome Measures

Unplanned readmission rate to the study‐site hospital within 180 days after discharge after hip replacement or repair.

Results

Unplanned readmission within 180 days occurred at a rate of 8.3% and varied significantly by discharge destination: home 5.1%, home with home health care services 10.5%, skilled nursing facility 12.3%, inpatient rehabilitation 4.2%, and other 42.9%. Variables from the surgical admission that were significantly associated with higher risk of readmission included admission severity, burden of comorbidities, any days in the intensive care unit, long length of stay, and cost. When controlling for multiple independent risk factors, discharge to inpatient rehabilitation (P = .015) remained a significant independent predictor of lower risk of readmission within 180 days.

Conclusion

Discharge to acute inpatient rehabilitation was associated with a lower risk of hospital readmission. Identification of patients with orthopedic procedures who may benefit from inpatient rehabilitation and further medical management before discharge from the acute hospital may be an important strategy in prevention of hospital readmission.
Does a 3‐Sip Test Detect Dysphagia in Acute Stroke Rehabilitation Patients?
Authors: Kopey Stephanie A. , Chae John , Vargo Mary M.
Published: September 2010

Objectives

(1) Evaluate sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of a 3‐sip test within 24 hours of acute stroke as a screening for clinically relevant dysphagia during acute rehabilitation. (2) For those patients who pass the 3‐sip test, identify factors predictive of later detection of clinically relevant dysphagia.

Design

A retrospective review.

Setting

Acute stroke rehabilitation unit of a tertiary academic medical center.

Patients

223 patients undergoing dysphagia screening after stroke.

Main Outcome Measure

Development of clinically relevant dysphagia.

Results

Seventeen of 223 patients (7.6%) failed the 3‐sip test. Of the 206 patients who passed the 3‐sip test, 57 (27.7%) manifested clinically relevant dysphagia. Sensitivity and specificity of the 3‐sip test were 20.8% and 98.7%, respectively. PPV and NPV were 88.2% and 72.3%, respectively. Among those who passed the 3‐sip test, logistic regression identified the Functional Independence Measure (FIM) total score as the only independent predictor (B = −0.066, P < .001) of clinically relevant dysphagia. Of those patients who passed the 3‐sip test, 54.6% with an FIM total score <60 had clinically relevant dysphagia compared with 11.9% with an FIM total score >60.

Conclusions

The sensitivity of the 3‐sip test was poor for stroke rehabilitation patients. For those who passed the 3‐sip test, a low FIM total score was predictive of development of clinically relevant dysphagia. A high degree of clinical suspicion for dysphagia should remain after passing a 3‐sip screening test, especially for those with FIM total score <60.
A Valid and Reliable Clinical Determination of Footedness
Authors: Schneiders Anthony G. , Sullivan S. John , O'Malley Kate J. , Clarke Stephanie V. , Knappstein Stuart A. , Taylor Lauren J.
Published: September 2010

Objective

To develop a valid and reliable clinical performance measure of foot dominance.

Design

Prospective cross‐sectional study with repeated measures.

Setting

Laboratory.

Participants

A total of 175 healthy male and female subjects ages 16 to 37 years.

Interventions

A total of 12 lower limb functional performance skilled and unskilled tasks.

Main Outcome Measure

Internal consistency and reliability of selected measures.

Results

Principal components factor analysis with varimax rotation resulted in tasks being grouped into 3 components with Eigen values greater than 1, which explained 55% of the variance. An inventory of 4 skilled component tasks was found to reliably determine footedness. Internal consistency derived from Cronbach's alpha produced a value of 0.819 for the skilled tasks. Three of the 4 skilled tasks were found to have excellent reliability (>0.75) with almost perfect agreement.

Conclusions

Determining foot dominance is important in a rehabilitation setting, considering the normal laterality variation in cerebral hemisphere function, limb morphology, and motor performance parameters encountered in humans. This study developed an inventory of skilled performance tasks to reliably determine footedness. Four bilateral tasks were identified that had excellent test‐retest reliability and high internal consistency and are recommended as global determinants of footedness.
Accuracy of Ultrasound‐Guided Versus Palpation‐Guided Acromioclavicular Joint Injections: A Cadaveric Study
Authors: Peck Evan , Lai Jim K. , Pawlina Wojciech , Smith Jay
Published: September 2010

Objective

To describe a technique for sonographically guided acromioclavicular joint (ACJ) injections and compare its accuracy to palpation‐guided injections in a cadaveric model.

Design

Prospective laboratory investigation.

Setting

Procedural skills laboratory at a tertiary medical center.

Methods

A single experienced operator completed 10 sonographically guided and 10 palpation‐guided ACJ injections in unembalmed cadavers. Injection order was randomized and all injections were completed with diluted colored latex. Co‐investigators blinded to the injection technique dissected each specimen and graded colored latex location as accurate (in the ACJ), partially accurate (within and outside the ACJ), or inaccurate (no latex in the ACJ).

Main Outcome Measurements

Direct assessment of injected dye within the ACJ via dissection.

Results

All 10 sonographically guided ACJ injections accurately placed latex into the ACJ (100% accuracy), whereas only 4 of 10 (40%) palpation‐guided injections accurately placed latex within the ACJ (P = .0054).

Conclusions

This cadaveric investigation suggests that sonographic guidance can be used to inject the ACJ with a high degree of accuracy, and should be considered superior to palpation guidance. Clinicians should consider using sonographic guidance to inject the ACJ when diagnostic specificity is paramount or when otherwise clinically indicated.
The Use of Elevation and Dependency to Enhance the Predictive Value of Transcutaneous Oxygen Pressure Measurements in the Assessment of Foot Amputation Healing
Authors: Andrews Karen L. , Boon Andrea J. , Dib Mansour , Liedl David A. , Yacyshyn Alison , Yacyshyn Vincent
Published: September 2010

Objective

To determine whether transcutaneous oxygen pressure (TcPO2) measurements taken while the patient is supine, with the limb elevated, and/or with the limb dependent (below the level of the heart) can be used to predict the healing of partial‐foot amputations.

Design

Retrospective, observational study.

Setting

A tertiary care, outpatient, multidisciplinary practice.

Patients

A total of 373 patients who had supine, elevated, and dependent TcPO2 measurements and underwent partial‐foot amputation were identified by the use of a search of the Surgical Index database for procedure crossed with an electronic note retrieval database search.

Intervention

None.

Main Outcome Measurements

Amputation site healing.

Results

For patients who underwent partial‐foot amputation and healed in 3 months, the mean TcPO2 value was 40.37 torr (SD 0.09); in the delayed‐healing group, the mean TcPO2 value was 28.36 torr (SD 1.16); in the nonhealed group, the mean TcPO2 value was 22.79 torr (SD 1.14; P < .01 for each torr value). For the subgroup of patients with a TcPO2 greater than 20 torr and less than 40 torr, in whom healing is more difficult to predict, the use of maneuvers of elevation and dependency increased both the positive and negative predictive values (56% and 74%, respectively) of the test compared with the use of supine measurements in isolation.

Conclusion

Supine TcPO2 measurements can help predict amputation site healing in patients with ischemic wounds who require a partial‐foot amputation. For the subgroup of patients with TcPO2 values greater than 20 torr and less than 40 torr, adding TcPO2 measurements with the limb elevated and/or dependent further improves the posttest probability and predictive values of the TcPO2 measurements.
A multi-proxy approach to assessing isolation basin stratigraphy from the Lofoten Islands, Norway
Authors: Balascio Nicholas L. , Zhang Zhaohui , Bradley Raymond S. , Perren Bianca , Dahl Svein Olaf , Bakke Jostein
Published: September 2010

This study takes a comprehensive approach to characterizing the isolation sequence of Heimerdalsvatnet, a coastal lake in the Lofoten Islands, northern Norway. We use established methods and explore new techniques to assess changes in marine influence. Bathymetric and sub-bottom profiles were acquired to examine basin-wide sedimentation and a 5.8 m sediment core spanning the last 7800 cal yr BP was analyzed. We measured magnetic susceptibility, bulk organic matter properties, molecular biomarkers, diatom assemblages, and elemental profiles acquired by scanning X-ray fluorescence. These characteristics of the sediment reflect detailed changes in salinity and water column conditions as the lake was progressively isolated. Three distinct litho/chemo-stratigraphic units represent a restricted marine phase (7800–6500 cal yr BP), a transitional phase characterized by intermittent marine influence (6500–4900 cal yr BP), and complete isolation and freshwater sedimentation (4900 cal yr BP to present). Although there are uncertainties in the estimate of the threshold elevation of the lake, the timing of these phases generally corresponds with previous interpretations of the local relative sea-level history. This record captures sea-level regression following the Tapes transgression and supports the interpretation of a subsequent sea-level stillstand, dated in Heimerdalsvatnet from 6500 to 4900 cal yr BP.
Gross-Hopkins duality and the Gorenstein condition
Authors: Dwyer W. G. , Greenlees J. P. C. , Iyengar S. B.
Published: September 2010

Gross and Hopkins have proved that in chromatic stable homotopy, Spanier-Whitehead duality nearly coincides with Brown-Comenetz duality. We give a conceptual interpretation of this phenomenon in terms of a Gorenstein condition [8] for maps of ring spectra.
The Apocryphal Suicide of Saigō Takamori: Samurai,Seppuku, and the Politics of Legend
Authors: Ravina Mark J.
Published: September 2010

According to standard reference works, the Meiji leader Saigō Takamori committed ritual suicide in 1877. A close reading of primary sources, however, reveals that Saigō could not have killed himself as commonly described; instead, he was crippled by a bullet wound and beheaded by his followers. Saigō's suicide became an established part of Japanese history only in the early 1900s, with the rise ofbushidōas a national ideology. By contrast, in the 1870s and 1880s, the story of Saigō's suicide was just one of many fantastic accounts of his demise, which also included legends that he ascended to Mars or escaped to Russia. Remarkably, historians have treated Saigō's suicide as an unproblematic account of his death, rather than as a legend codified some four decades later. This essay links the story of Saigō's suicide to the rise of modern Japanese nationalism, and examines other Saigō legends as counternarratives for modern Japan.
Middle ear structures in fossorial mammals: a comparison with non‐fossorial species
Authors: Mason M. J.
Published: September 2010

A large data set, comprising certain measurements of middle ear structures in mammals, was compiled both from measurements made by the author and from the literature. Parameters of the middle ear apparatus believed to be important to audition were compared between fossorial and non‐fossorial species, in an attempt to identify general trends among fossorial groups. Although their tympanic membranes are not of unusual size, many fossorial mammals possess enlarged stapes footplate areas, resulting in low anatomical area ratios. Low anatomical lever ratios are also common, and the reduction or loss of middle ear muscles seems to be a consistent trend. These characteristics might be associated with poor sensitivity to airborne sound. Other features of the middle ear apparatus are more variable both between and within fossorial families. The middle ear ossicles of fossorial rodents, talpid moles and some golden moles were not found to differ in mass from those of non‐fossorial mammals of similar body size. The similar ossicular morphologies of these animals suggest convergent adaptation towards a subterranean environment, but the middle ear structure alone does not seem to explain the restricted hearing range observed in certain of these species. Some genera of golden moles possess extraordinarily hypertrophied auditory ossicles, which, relative to body mass, are the largest of all mammals for which data are available. These ossicles seem to be adaptations towards a form of inertial bone conduction, used for the detection of substrate vibrations. In stark contrast, the marsupial mole Notoryctes has particularly small ossicles. The unusual middle ear structures of this animal may well be degenerate.