bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and implementation of a diffserv enabled HFC system offering Strict QoS support
Authors: Angelopoulos John , Leligou Helen‐Catherine , Boettle Dietrich , Wahl Stephan , Christ Paul , Jaehnert Juergen
Published: September 2008

Widespread deployment of Hybrid Fiber Coaxial (HFC) systems created a new residential access platform upgrading traditional cable TV networks, which were limited to distributed services. This evolution is driven by demand for faster Internet access from customers frustrated by slow telephone line and ISDN modem speeds. As residential traffic with voice and video‐intensive content proliferates, the current generation of cable modems, which are oriented towards best‐effort traffic, will need to be enhanced with new capabilities to handle the increased bandwidth and quality requirements. To integrate telecom services presenting diverse quality requirements over the same HFC access infrastructure necessitates a degree of isolation of traffic classes. The difficulty of handling finer aggregations because of the limited MAC reservation resources and the cost limitation of residential access make the scalability of the differentiated services architecture as relevant in the HFC access network as in any traffic multiplexer. An implementation integrating IP and ATM and aligning the system to the DiffServ philosophy is presented in this paper. It constitutes an affordable system solution for residential customers enabling the support of QoS‐demanding services.
α-Antitrypsin Deficiency
Authors: Alagille Daniel
Published: September 2008

Liver disease related to a-1-antitrypsin deficiency occurs only in Pi ZZ homozygous children. Eleven per cent of Pi ZZ infants present with prolonged neonatal cholestasis. In our group, 25 of 45 Pi ZZ infants with prolonged neonatal cholestasis presented with later cirrhosis. Persistence of jaundice beyond the sixth month of age, early development of splenomegaly, persistence of hard hepatomegaly and liver function abnormalities, and early portal fibrosis have a poor prognostic significance. The most severe course occurs in infants with an early histologic pattern of paucity of interlobular bile ducts. Portal hypertension was present in 19 of 25 children presenting with cirrhosis; 8 of 25 Pi ZZ children with cirrhosis died during childhood.

Long-term protein-restricted diet and portal systemic shunts were helpful in treatment of four Pi ZZ children with cirrhosis; however, the long-term course in Pi ZZ children with cirrhosis is unpredictable.
An Assessment of Orthotopic Liver Transplantation in Acute Liver Failure
Authors: Williams Roger , Gimson A. E. S.
Published: September 2008

Mortality of fulminant hepatic failure with standard supportive therapy is high (80 to 85%), but unfortunately most patients present to hospital already in Grade IV encephalopathy with severe liver dysfunction, and many have secondary organ damage. If seen earlier, during Grade III encephalopathy, recent experience with charcoal hemoperfusion can give good results (65% survival). Transplantation has a place in those patients who do not respond, and in cases with early Grade IV encephalopathy. Transplantation should also be considered in patients with subacute hepatic failure in whom mortality is equally high and progression to cirrhosis may occur in those who recover. In both groups, the ability to correct the hemorrhagic diathesis and an adequate supply of donor organs are essential to achievement of a successful transplant at this critical time.
Hepatic Vein Thrombosis (Budd-Chiari Syndrome)
Authors: Maddrey Willis C.
Published: September 2008

Hepatic vein thrombosis (Budd-Chiari Syndrome) is a rare disorder resulting from obstruction to the outflow of blood from the liver. The characteristic pathologic findings are intense congestion most pronounced around the terminal hepatic venules, cell necrosis, and a scant inflammatory reaction. Major clinical manifestations include hepatomegaly, right upper quadrant abdominal pain, and ascites. Disorders associated with hepatic vein thrombosis include those associated with a thrombotic tendency, such as polycytermia vera and paroxysmal nocturnal hemoglobinuria. Use of oral contraceptive agents probably increases tendency to develop hepatic vein thrombosis. Biochemical tests of the liver are of little value. The hepatic scan may be useful in suggesting the diagnosis with a marked decrease in uptake of isotope over affected areas of the liver. The diagnosis is confirmed by inferior vena caval and attempted hepatic venous catheterization. An associated thrombosis of the inferior vena cava is frequently found. Therapy in hepatic vein thrombosis is directed towards correction, in so far as possible, the underlying disorder, prevention of further extention of thrombosis, and management of ascites. Side-to-side portacaval or mesocaval shunt operation may convert the portal vein into an effective hepatic outflow vessel and reduce intrahepatic pressure and decrease injury. Mesoatrial shunts have proven useful in a few patients with hepatic vein thrombosis and either an inferior vena caval thrombosis or a marked pressure gradient from the abdomen to the thorax from ascites and an hypertrophied caudate lobe of the liver. For patients with extensive hepatocellular disease and portal hypertension, hepatic transplantation would seem to offer the best chance for survival.
Orthotopic Liver Transplantation in Groningen, The Netherlands (1979-1983)
Authors: Krom Ruud A. F. , Gips Chris H. , Houthoff Hendrik J. , Newton Douglas , Waaij Dirk V. D. , Beelen José , Haagsma Elizabeth B. , Slooff Maarten J. H.
Published: September 2008

From March, 1979 to March, 1983, 26 orthotopic liver transplantations and 1 retransplantation were performed in our center. Sixteen patients are alive, 5 beyond22 years and 1 longer than 4 years after transplantation. The actuarial 1- and 2-year survival is 60%. Factors contributing to this result are patient selection and biliary anastomosis. In cirrhotic patients, the degree of deterioration of liver function correlated with survival; in patients with hepatocellular carcinoma, extrahepatic spread of tumor was the most frequent limiting factor. Choledochocholedochostomy with a widening plasty had a low complication rate providing that the arterial blood supply was undisturbed. Until now, HLA-matching has not contributed to the result of liver transplantation, although the effect for long-term survival is still unknown. The high survival rate and excellent quality of life of long-term survivors justify liver transplantation as treatment for otherwise noncurable liver diseases.
Human Liver Transplantation: Analysis of Data on 540 Patients from Four Centers
Authors: Scharschmidt Bruce F.
Published: September 2008

The results of liver transplantation in a total of 540 patients from four centers in the United States and Western Europe have been collated. Twenty-five per cent of all transplants were performed for neoplastic disease. One- and 3-year survivals for this group were approximately 26 and 12% overall, and survival differed little for patients transplanted before and after January 1, 1980. Among the 44% of patients transplanted for endstage cirrhosis, 3-year survival was lowest for patients with alcoholic cirrhosis (20%). Three-year survival was greater for patients with nonalcoholic cirrhosis (29% overall), did not differ markedly among the various subtypes, and was greater for patients transplanted after January 1, 1980 (42%), as compared with before (22%). Patients with biliary atresia, sclerosing cholangitis, and metabolic and miscellaneous disorders constituted the remaining 30% of patients; 3-year survival varied from about 20 to 44% overall for the various subgroups, with a consistent trend toward improved survival among patients transplanted after January 1, 1980. The use of cyclosporin may not wholly explain this improved survival among more recently transplanted patients. Quality of life for transplant recipients surviving at least 3 months, as judged by a limited amount of data regarding time-in-hospital and functional status, appears to be good.
Techniques for Studying Biliary Secretion: Electrolytes in Bile
Authors: Bear Christine E. , Strasberg Steven M.
Published: September 2008

A major limitation in understanding bile formation has been technical. The liver and ductular epithelium are relatively inaccessible, necessitating indirect techniques of uncertain validity. This is well seen in attempts to define the role of electrolyte secretion in bile. It is widely agreed that bile salts stimulate a component of canalicular flow and that inorganic electrolyte secretion is stimulated by bile salts. The choleretic efficiency of a bile salt is directly related to the magnitude of the electrolyte effect. But there is no consensus regarding how and where bile salts stimulate electrolyte secretion. Some evidence points to a paracellular route by processes of solvent drag and diffusion. Other studies suggest stimulation of specific transcellular electrolyte pathways. It has been believed that canalicular bile salt-independent bile flow is generated by active blood-to-bile electrolyte transport. Actually, available methods do not permit us to conclude with absolute certainty that there is canalicular bile salt-independent flow, although there is considerable evidence for it. New studies suggest that electrolyte transport in this type of flow is passive and that flow is due to transport of organic anions. Ductular flow does seem to be due to active transport of electrolytes, particularly bicarbonate. Better and more direct techniques are required to settle the controversies in this area.
Biliary Proteins
Authors: Reuben Adrian
Published: September 2008

The study of biliary proteins has grown enormously in the last 10 years. Although much has been recently learned about the nature, origin and hepatobiliary transport of these proteins, little is known of their function in bile or their effect on its physical state. This review will focus on description of the proteins and mechanisms by which they are secreted into bile.
Bile Salts as Atypical Surfactants and Solubilizers
Authors: Mukerjee Pasupati , Moroi Yoshikiyo , Murata Moriyasu , Yang Alex Y. S.
Published: September 2008

Recent research has suggested that self-association of bile salts does not follow the micellar pattern of self-association exhibited by typical flexible chain surfactants and detergents. A working model for the self-association of bile salts is proposed. It includes a mild degree of cooperativity in the early stages of the growth of aggregates and coexistence of a number of aggregates of different aggregation numbers. The polydispersity implies an increase in the average aggregation number with increasing concentration of the bile salt. Bile salts can be purified by foam fractionation. Surface tension data for sodium cholate are in agreement with the above qualitative model of self-association. An isoextraction method is useful for estimating monomer activities. Results for sodium deoxycholate suggest little self-association in dilute solutions and a mildly cooperative self-association at higher concentrations. A comparative study of the interactions of the fluorescent probe, 2-p-toluidinyl-naphthalene-6-sulfonate, with sodium alkyl sulfates and sodium deoxycholate indicates that bile salts may differ significantly from classical micellar systems in their solubilization characteristics also. The evidence suggests strongly that a specific adduct formation with an optimum number of bile salt anions may be important in solubilization brought about by the rigidity and the complex shape of the bile salt anions.
Counter-Ion Binding by Bile Acid Solutions
Authors: Rajagopalan Natarajan , Lindenbaum Siegfried
Published: September 2008

The binding of Ca2+ to micelles of glycine and taurine bile acid conjugates was studied using a Ca2+−-specific electrode. An investigation of the effect of buffer concentration, pH, added electrolyte and lecithin was also performed. The results indicate that the binding of Ca2+ to bile salt micelles is dependent on the number of hydroxyl groups on the steroid nucleus and on the nature of the head conjugating group, namely, glycine or taurine. It is speculated that the binding of Ca2+ to bile salt micelles may act as one mechanism to lower Ca2+ activity in bile and, thus, reduce its tendency to precipitate as insoluble calcium salts and further growth into gallstones.
Bile Salt Structure and Phase Equilibria in Aqueous Bile Salt and Bile Salt-Lecithin Systems
Authors: Carey Martin C.
Published: September 2008

The hydrophilic-hydrophobic balance of bile salt monomers can be readily quantified by their elution sequence during reverse-phase high-performance liquid chromatography. Such studies have demonstrated that subtle variations in bile salt structure have profound effects on the hydrophilic-hydrophobic balance of this important family of detergent-like molecules. The common trihydroxy bile salt, cholate, is more hydrophilic than dihydroxy bile salts with alpha-oriented OH groups. In contrast, dihydroxy bile salts with one equatorial OH function are more hydrophilic than cholate. Hydrophilic bile salts have, in general, higher critical micellar concentrations than do hydrophobic bile salts and their primary micelles polymerize less readily to form secondary micelles either with increasing bile salt concentrations or with increases in ionic strength. Hydrophilic bile salts also disperse lecithin into mixed micelles at a slower rate than do hydrophobic bile salts. The structure of mixed bile salt-lecithin micelles is more complex than previously believed and varies with bile salt-to-lecithin ratio. These micelles are disc-like in which bile salts saturate the lecithin bilayer “core” presumably as reverse micelles, as well as coating the perimeter as a bilayered “ribbon”. The ratio of bile salt to lecithin in the bilayer and the intermicellar monomeric bile salt concentration (critical micellar concentration) determines the macroscopic phase limit. With the common bile salt species, the lecithin-to-bile salt phase limit does not correlate closely with the hydrophilic-hydrophobic balance of the bile salt monomers. However, with very hydrophilic bile salts such as the pansulfated species in physiological ionic strength, the equilibria between the large intermicellar bile salt concentrations and the bile salt molecules interacting with lecithin in mixed micelles favors the former state. As a consequence, the lecithin-to-bile salt molar ratio at the phase limit is greatly reduced. However, when the charges of the sulfate groups are electrostatically shielded (e.g., in 4 MNaCl), the lecithin-to-bile salt molar ratio at the phase limit approaches and even exceeds that of the nonsulfated bile salt species.
Aqueous Bile Salt-Lecithin-Cholesterol Systems: Equilibrium Aspects
Authors: Carey Martin C.
Published: September 2008

Cholesterol is solubilized by bile salt and bile salt-lecithin micelles without appreciable alteration in preexisting micellar size or structure. In dilute (˜ 3 gm per dl) model bile, but not in concentrated (˜ 10 gm per dl) systems, supramicellar concentrations of cholesterol are also solubilized in “stable” microdispersions of small lecithin-cholesterol vesicles (˜ 200 to 400 A in radius). Under physical-chemical conditions of physiological importance, the micellar solubilities of cholesterol are influenced by the total lipid concentrations, lecithin-to-bile salt ratio and bile salt species. The hydro-philic-hydrophobic balance of the bile salt monomer also influences the number and composition of precipitate phases coexisting in equilibrium with saturated micelles. When diluted below the critical micellar concentration (more correctly, the intermicellar concentration) of the bile salt species, the systems no longer contain micelles, but cholesterol remains dispersed in unilamellar liposomes that form spontaneously from the mixed micellar concentrations of the biliary lipids.
Metastability Behavior of Supersaturated Bile
Authors: Holzbach Thomas R.
Published: September 2008

Major discrepancies exist between both the degree (or cholesterol excess limit) and duration of metastable cholesterol supersaturation in concentrated model biles and native human gallbladder bile. The comparatively reduced metastability of in vitro model systems suggests that a stabilizing factor is absent in these more concentrated systems. In contrast, the metastable supersaturation behavior of the dilute model and hepatic biles is similar particularly with respect to their markedly prolonged metastability, i.e., nucleation time. These observations suggest that changes in the lipid component alone (e.g., structural alterations resulting from dilution) could account for the similarity. The structural component in hepatic biles and in comparable dilute model systems appears to be small unilamellar vesicles which have an unusual duration of metastability and a high capacity for cholesterol transport. In this sense, metastability properties characteristic of pure micellar systems are neither observed nor to be expected in human hepatic bile and are only partially responsible for metastability in gallbladder bile.
Factors Influencing Cholesterol Nucleation in Bile
Authors: Holzbach Thomas R.
Published: September 2008

Dilution induces structural alterations (i.e., vesicle formation) in the lipid particles of supersaturated human hepatic bile and in dilute model bile systems of comparable composition. These alterations strikingly increase both the degree and duration of metastable supersaturation. Concentrated normal human gallbladder bile also shows an increased but less striking degree and duration of metastability compared to comparable model biles. These differences, particularly with respect to gallbladder bile, cannot be attributed solely to compositional or lipid structural differences between native and model systems. They imply that additional factors are responsible for metastability. Furthermore, recent data suggest that biliary proteins may be involved. A limited number of these unidentified proteins have been shown to have the capacity to prolong metastability in supersaturated in vitro model systems. Thus, these recombined systems more nearly resemble the behavior of native bile. The mechanism of the nucleation inhibitory effect of these proteins is not clearly established.
Evidence for a Nucleation Defect in Bile from Gallstone Patients
Authors: Gallinger Steven , Harvey Robert P.C. , Strasberg Steven M.
Published: September 2008

When modern methods of estimating cholesterol saturation in bile were first applied to human bile samples, it seemed that a clear distinction could be made between normal and abnormal biles on the basis of cholesterol saturation. Supersaturation of bile with cholesterol appeared to be the only critical defect required for stone formation. A variety of evidence has now accumulated which indicates that a nucleation defect is also important. Chief among these observations is the fact that gallbladder bile from stone patients nucleates cholesterol crystals more rapidly than equally saturated gallbladder bile from controls. To determine whether the gallbladder contributes to the nucleation defect, hepatic and gallbladder bile nucleation times have been compared. Although the former is more supersaturated, the latter nucleates faster suggesting that the gallbladder is important. In another study, the nucleation times of crystal-free abnormal bile, normal bile and a mixture of the two were obtained. The mixture nucleated as rapidly as the abnormal bile even when the abnormal bile contributed only 5% of the volume of the mixture. This indicated that a nucleating factor is added to abnormal bile in the gallbladder.
Animal Models of Calcium Cholelithiasis
Authors: Hofmann Alan F.
Published: September 2008

Bile contains four calcium anions which are readily precipitated by calcium: bilirubinate, “palmitate”, carbonate and phosphate. Precipitation of insoluble calcium salts is common in calculous biliary disease. All animal models of calcium cholelithiasis probably share a common pathogenesis-an increased concentration of a calcium-sensitive anion. In calcium bilirubinate cholelithiasis, an increased concentration of bilirubinate occurs. In mice, this occurs in animals having a genetic hemolytic anemia; in rats, it may be induced by an essential fatty acid in combination with diet modification; in dogs, by a low-taurine, low-protein diet; and in prairie dogs, by ileal resection which probably increases the bilirubinate/bile acid ratio in bile. In the two models of calcium-bile acid cholelithiasis, an increased biliary concentration of a calcium-sensitive glycine conjugated bile acid is induced by administration of a suitable precursor. In the rabbit, gallstones composed mostly of calcium allodeoxycholyl glycine are induced by the feeding of 5β-cholestan-3β-ol. In the taurine-deficient rat, the feeding of lithocholate leads to formation of gallstones which contain a mixture of calcium lithocholyl glycine and 3α,6β-dihydroxy cholanoyl glycine. These animal models may be of value in testing agents designed to lower calcium activity in bile.
The Role of Calcium in the Pathogenesis of Gallstones: Ca++ Electrode Studies of Model Bile Salt Solutions and Other Biologic Systems†
Authors: Moore Edward W.
Published: September 2008

Calcium is present in all pigment gallstones as a salt of one or more of the anions in bile which are most readily precipitable by calcium: (i) carbonate; (ii) bilirubinate; (iii) phosphate, and (iv) “palmitate”. We term these “calcium-sensitive” anions. In addition, since cholesterol stones have been found to contain pigment stone centers, we postulate that calcium precipitation in bile is a critical event in the initiation of cholesterol gallstones, so that the latter should be considered a two-stage process: (i) precipitation of calcium salts to form a nidus, and (ii) precipitation of cholesterol from its supersaturated state on this nidus. Any measure which will reduce free [Ca++] in bile will reduce calcium lithogenicity; possible ways to reduce [Ca++] in bile are presented. One way is to increase Ca++ binding by normal biliary constituents; we have recently pointed out that bile salts are important buffers for Ca++ in bile by virtue of binding to both free and micellar bile salts. Here, we consider some of our Ca++ electrode studies of taurocholate, glycocholate, serum albumin, and simple molecules having terminal carboxyl (COO−) or sulfonic (SO−3) ions. A brief history of the development of the Ca++ electrode is given, along with theoretical considerations of ionic activities and techniques of electrode measurements. From the various studies, a unifying hypothesis is proposed for the structural requirements of Ca++−binding to proteins (albumin) and free monomeric bile salts. For proteins, unconjugated bile salts and glycine-conjugated bile salts, it is proposed that Ca++ binding involves a reversible ion-exchange “site” in which a Ca++ ion is interposed between carboxyl (CO0− ) and hydroxyl (OH) groups. For taurine-conjugated bile salts, this “site” is proposed to involve the interposition of a Ca++ ion between the side-chain SO−3 and cholanic ring OH groups. These studies are a first step toward modulation of Ca++ activity in bile.
The assessment of genotoxic effects of wastewater from a fertilizer factory
Authors: Durgo Ksenija , Oreščanin Višnja , Lulić Stipe , Kopjar Nevenka , elježić Davor Ž , Čolić Jasna Franekić
Published: September 2008

In this study we investigated cytotoxic, mutagenic and genotoxic effects of different concentrations of wastewater from the phosphoric gypsum depot near the factory for fertilizing agents ‘INA Petrokemija’ (Kutina, Croatia). The Ames test was performed on Salmonella typhimurium TA98 and TA100 strains, in the presence of S9 mix, glutathione and buffer, respectively. Cytotoxicity was studied on human laryngeal carcinoma cells (HEp2) and human cervical cells (HeLa). The level of lipid peroxidation in these two cell lines was evaluated in parallel. To establish the levels of primary DNA damage, the alkaline comet assay was performed on treated human peripheral blood leukocytes. No mutagenic effects of phosphoric gypsum on Salmonella typhimurium strains in the presence of S9 mix, GSH or PBS were observed. However, strong cytotoxic effect was observed on both human cell lines when they were treated with different concentrations of wastewater. Lipid peroxidation was induced and increased by prolonged time of incubation, highlighting that the damage was not repaired, but increased with the time of incubation. The results of the alkaline comet assay indicate significant DNA damaging potential of wastewater for human leukocytes. Since phosphoric gypsum transport water in its present composition and acidity is highly toxic and acts as prooxidant, causing free radicals formation and DNA damage, urgent neutralization/purification of the wastewater to a level acceptable for disposal into the environment is mandatory. Copyright © 2008 John Wiley & Sons, Ltd.
Concentration of aluminium in breast cyst fluids collected from women affected by gross cystic breast disease
Authors: Mannello Ferdinando , Tonti Gaetana A. , Darbre Philippa D.
Published: September 2008

Gross cystic breast disease (GCBD) is the most common benign breast disorder, but the molecular basis of cyst formation remains to be identified. If the use of aluminium‐based antiperspirant salts is involved in the etiology of gross breast cyst formation, it might be expected that aluminium would be at elevated levels in human breast cyst fluid (BCF). Aluminium was measured by ICP‐MS in 48 samples of BCF, 30 samples of human blood serum and 45 samples of human breast milk at different stages of lactation (colostrum, intermediate, mature). The median level of aluminium in apocrine type I BCF (n = 27, 150 µg l−1) was significantly higher than in transudative type II BCF (n = 21, 32 µg l−1; P <0.0001). By comparison, aluminium measurements gave a median concentration of 6 µg l−1 in human serum and 25 µg l−1 in human breast milk, with no difference between colostrum, intermediate and mature milk. Levels of aluminium were significantly higher in both types of BCF than in human serum (P <0.0001). However when compared with human breast milk, aluminium levels were only significantly higher in apocrine type I BCF (P <0.0001) and not in transudative type II BCF (P = 0.152). It remains to be identified why such high levels of aluminium were found in the apocrine type I BCF and from where the aluminium originated. However, if aluminium‐based antiperspirants are found to be the source and to play any causal role in development of breast cysts, then it might become possible to prevent this common breast disorder. Copyright © 2008 John Wiley & Sons, Ltd.
Role and effective treatment of dispersive forces in materials: Polyethylene and graphite crystals as test cases
Authors: Barone Vincenzo , Casarin Maurizio , Forrer Daniel , Pavone Michele , Sambi Mauro , Vittadini Andrea
Published: September 2008

A semiempirical addition of dispersive forces to conventional density functionals (DFT‐D) has been implemented into a pseudopotential plane‐wave code. Test calculations on the benzene dimer reproduced the results obtained by using localized basis set, provided that the latter are corrected for the basis set superposition error. By applying the DFT‐D/plane‐wave approach a substantial agreement with experiments is found for the structure and energetics of polyethylene and graphite, two typical solids that are badly described by standard local and semilocal density functionals. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Biomimetic mineralization synthesis of calcium‐deficient carbonate‐containing hydroxyapatite in a three‐dimensional network of bacterial cellulose
Authors: Shi Shuaike , Chen Shiyan , Zhang Xiang , Shen Wei , Li Xin , Hu Weili , Wang Huaping
Published: September 2008

BACKGROUND: Both hydroxyapatites (HAp) and bacterial cellulose (BC) are excellent biomaterials. The former has outstanding osteoconductivity and bioactivity, while the latter has been proven to be a remarkably versatile biomaterial. By alkaline treatment, Ca2+ activation, and biomimetic mineralization, the nanocomposites (CaDHCAp/BC) consisting of calcium‐deficient carbonate‐containing hydroxyapatite (CaDHCAp) in the three‐dimensional (3D) network of BC nanofibers were synthesized.

RESULTS: The CaDHCAp/BC nanocomposites obtained were characterized by inductively coupled plasma atomic emission spectroscopy (ICP‐AES), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X‐ray diffraction spectroscopy (XRD). The results indicated that alkaline treatment improved the apatite nucleation ability of BC, and the apatite crystals deposited along BC nanofibers were partially substituted with calcium carbonate and the uniform spherical apatite particles were composed of squama‐shaped nano‐sized apatite crystals. The crystallite sizes of apatite crystals are below 10 nm and the crystallinities are below 1%. The formation mechanism of CaDHCAp crystals along the BC fibers was described.

CONCLUSION: Alkaline treatment was introduced before the biomimetic mineralization process. Compared with the results without alkaline treatment, the mineralization efficiency was obviously improved. The nanocomposites obtained may have potential application as an orthopedic biomaterial. Copyright © 2008 Society of Chemical Industry
A causal analysis of the impact of job performance on the voluntary turnover process
Authors: Jackofsky Ellen F. , Slocum John W.
Published: September 2008

A model of job turnover that includes job performance as a predictor was presented and tested longitudinally using path analysis. Out of seven hypothesized paths, six were significant and in the predicted direction. The seventh one was significant but in a direction opposite to that predicted.
Psychological ownership within the job design context: revision of the job characteristics model
Authors: Pierce Jon L. , Jussila Iiro , Cummings Anne
Published: September 2008

In this paper, we offer a theoretical modification to the Hackman and Oldham (1975) Job Characteristics Model by integrating research on the psychological aspects of job design with emerging theory on psychological ownership. We develop the connection between job design and (a) the motives facilitating psychological ownership, (b) the routes through which psychological ownership emerges, and (c) the individual‐level outcomes (e.g., emotional, attitudinal, motivational, and behavioral) that result from an employee's psychological ownership of his or her job. Our work covers several previously ignored positive and negative effects. We conclude by positioning psychological ownership as a plausible substitute for other proposed mediating psychological states in the job design–employee response relationship. Copyright © 2008 John Wiley & Sons, Ltd.
Volatile components in flavour concentrates from crayfish processing waste
Authors: Cha Yong‐Jun , Baek Hyung‐Hee , Hsieh Thomas C‐Y
Published: September 2008

Volatile components in flavour concentrates prepared from crayfish (Procambarus clarkii Girard) processing waste at two temperatures (85°C and 100°C) were compared. The presence of 121 compounds was established. Among these, 78 compounds were positively identified of which 50 were detected in crayfish for the first time. These compounds were mainly N‐ and S‐containing compounds, ketones and aldehydes. The amounts of aldehydes and ketones were 1.5 and 1.4 times higher in the 85°C concentrates, respectively; and the amounts of N‐containing compounds were 2.3 times higher in the 100°C concentrates.
Multidimensional gas chromatography with capillary flow technology and LTM‐GC
Authors: Luong Jim , Gras Ronda , Yang Grace , Cortes Hernan , Mustacich Robert
Published: September 2008

2‐D GC is a logical and cost effective extension to 1‐D GC for improving the separation resolution, selectivity, and peak capacity of an analytical system. The advent of electronic pressure control systems that are accurate to the third decimal place, combined with recently innovated chromatographic devices such as capillary flow technology, has eliminated many deficiencies encountered in current conventional 2‐D GC by making the technique reliable and simple to implement in both production and research analytical facilities. Low thermal mass GC (LTM‐GC) was successfully integrated with capillary flow technology to further enhance overall 2‐D GC chromatographic system performance by providing not only faster throughput via rapid heating and cooling, but independent temperature control for each dimension to maximize separation power. As an example, despite the enhanced peak capacity obtained from conventional 2‐D GC, alkyl naphthalene isomers such as 2,3‐dimethyl and 1,4‐dimethyl naphthalene coeluted. These two critical compounds were well resolved (R = 5.2) using 2‐D GC with LTM‐GC with a similar analytical time. This paper demonstrates the benefits of combining capillary flow technology with LTM‐GC to provide major enhancements to conventional 2‐D GC. The synergy of these techniques is highlighted with practical industrial applications.
Multidimensional LC×LC analysis of phenolic and flavone natural antioxidants with UV‐electrochemical coulometric and MS detection
Authors: Hájek Tomáš , Škeříková Veronika , Česla Petr , Vyňuchalová Kateřina , Jandera Pavel
Published: September 2008

A comprehensive 2‐D LC×LC system was developed for the separation of phenolic and flavone antioxidants, using a PEG‐silica column in the first dimension and a C18 column with porous‐shell particles or a monolithic column in the second dimension. Combination of PEG and C18 or C8 stationary phase chemistries provide low selectivity correlations between the first dimension and the second dimension separation systems. This was evidenced by large differences in structural contributions to the retention by ‐COOH, ‐OH and other substituents on the basic phenol or flavone structure. Superficially porous columns with fused core particles or monolithic columns improve the resolution and speed of second dimension separation in comparison to a fully porous particle C18 column. Increased peak capacity and high orthogonality in different 2‐D setups was achieved by using gradients with matching profiles running in parallel in the two dimensions over the whole 2‐D separation time range. Multi‐dimensional set‐up combining the LC×LC separation on‐line with UV and multi‐channel coulometric detection and off‐line with MS/MS technique allowed positive peak identification. The Coularray software compensates for the effects of the baseline drift during the gradient elution and is compatible with parallel gradient comprehensive LC×LC technique. Furthermore, it provides significant improvement in the sensitivity and selectivity of detection in comparison to both UV and MS detection. The utility of these systems has been demonstrated in the analysis of beer samples.
Solid‐phase extraction method for determination of volatile compounds in traditional balsamic vinegar
Authors: Durán Guerrero Enrique , Chinnici Fabio , Natali Nadia , Marín Ramón Natera , Riponi Claudio
Published: September 2008

A solid‐phase extraction method for the determination of volatile compounds in traditional balsamic vinegar (TBV) has been developed. The optimisation has been carried out using a two‐level factorial design expanded further to a central composite design. LiChrolut‐EN SPE cartridges were used and the optimised analytical conditions were: 7 g of TBV diluted 1:4, 5 mL of washing water, and elution with 10 mL of dichloromethane. The linear ranges and detection and quantitation limits were adequate for the analysis of the studied compounds in TBV. The accuracy of the method was also studied: recoveries up to 80% and repeatability values lower than 15% were obtained for the majority of the studied compounds. Two TBVs of different age were analysed by the optimised method.
Dispersion engineering with resonant‐type metamaterial transmission lines
Authors: Sisó G. , Gil M. , Aznar F. , Bonache J. , Martín F.
Published: September 2008

Metamaterial transmission lines are artificial lines consisting on a host conventional line (such as a microstrip or a coplanar waveguide) loaded with reactive elements. The main relevant characteristic of these propagating structures is the fact that, due to the greater number of parameters (as compared to conventional lines), it is possible to tailor (engineer) their dispersion characteristics to achieve certain functionalities not achievable though conventional lines. Enhanced bandwidth components and multiband components are the main benefits of dispersion engineering with metamaterial transmission lines. In this paper, dispersion engineering will be carefully reviewed, and several examples illustrative of the application of this technique to microwave circuit design will be reported.
Fabrication of Conjugated Polymer Supramolecules in Electrospun Micro/Nanofibers
Authors: Yoon Jaewon , Kim Jong‐Man
Published: September 2008

A combination of top‐down (electrospinning for fabrication of high surface area micro/nanofibers) and bottom‐up (creation of supramolecular structures through self‐assembly processes in fiber) approaches has enabled the generation of conjugated polymer‐embedded fibers. The efficiency of fiber formation, encapsulated with colorimetric, and fluorogenic conjugated polydiacetylene supramolecules, was dependent on electrospinning conditions, such as concentration, molecular weight, type of matrix polymer, and solvent. In general, electrospinning of a chloroform solution containing 1.6 wt.‐% of a diacetylene monomer and 4 wt.‐% PEO of molecular weight 300 000 g · mol−1 followed by 254 nm UV irradiation resulted in clean formation of polydiacetylene‐embedded fibers. In addition, UV irradiation during electrospinning can be used for in situ and continuous generation of polydiacetylenes‐encapsulated fibers.

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Macromol. Chem. Phys. 18/2008
Authors: Kahveci Muhammet U. , Tasdelen M. Atilla , Cook Wayne D. , Yagci Yusuf
Published: September 2008

Cover: The cover schematically shows how photoinitiated cationic polymerization of vinyl ethers is achieved in aqueous medium by using diphenyliodonium iodide (DPII) in the presence of a water‐tolerant Lewis acid, ytterbium triflate (Yb(OTf)3). Further details can be found in the article by M. U. Kahveci, M. A. Tasdelen, W. D. Cook, and Y. Yagci* on page 1881.
An experimental test of brand insulation against competitor attacks: Effects of consumer heterogeneity and residual desire
Authors: DelVecchio Devon , Heath Timothy B.
Published: September 2008

Price discounts generally move consumers from lower‐quality brands to higher‐quality brands more than from higher‐quality brands to lower‐quality brands. This asymmetry can reverse, however, to favor the lower‐quality brand when improvements are made to product quality. Whether such variations exist when the goal is to retain rather than steal customers remains untested and constitutes the focus of this study. Experimental results indicate that customer retention strategies tend to favor higher‐quality brands. Higherquality brands are able to retain customers by matching the form of the lower‐quality brand's attack (price reduction or quality improvement). For lower‐quality brands, matching is effective only in the case of a price attack by a higher‐quality brand. Furthermore, higher‐quality brands are able to effectively retain customers with price reductions that are smaller than the discount offered by a lower‐quality competitor, whereas lower‐quality brands must match the magnitude of a discount by a higher‐quality brand to retain customers. The findings suggest that differences in customer retention across quality levels arise from (1) heterogeneity among consumers of different quality levels in the relative weightings of price and quality, and (2) switching decisions based on reasons that are biased toward continuing to purchase, or moving to, higher quality products. © 2008 Wiley Periodicals, Inc.
Mutation analysis of Parkin, PINK1, DJ‐1 and ATP13A2 genes in Chinese patients with autosomal recessive early‐onset Parkinsonism
Authors: Guo Ji‐Feng , Xiao Bin , Liao Bing , Zhang Xue‐Wei , Nie Li‐Luo , Zhang Yu‐Hu , Shen Lu , Jiang Hong , Xia Kun , Pan Qian , Yan Xin‐Xiang , Tang Bei‐Sha
Published: September 2008

Autosomal recessive early‐onset Parkinsonism (AREP) has been associated with mutations in the Parkin, PINK1, DJ‐1, and ATP13A2 genes. We studied the prevalence of mutations in all four genes in 29 Chinese unrelated families with AREP using direct sequencing analysis and real‐time quantitative PCR analysis assay. There are 14 families (48.3%) with mutations of Parkin gene, 2 families (6.9%) with mutations of PINK1 gene, and 1 family (3.4%) with mutation of DJ‐1 gene. No pathogenic mutations in ATP13A2 gene were found in these families. Three Parkin gene mutations (c.G859T, c.1069‐1074delGTGTCC, and c.T1422C) and one DJ‐1 gene mutation (c.T29C) have not been reported previously. In conclusion, Parkin gene mutation is the most common pathogenic factor in Chinese patients with AREP. Mutations of DJ‐1 and PINK1 gene are also found in Chinese families with AREP. Mutations in ATP13A2 gene may be rare in Chinese families with AREP. © 2008 Movement Disorder Society
Extracting more information from behaviour checklists by using components of mean based scores
Authors: Taffe John R. , Tonge Bruce J. , Gray Kylie M. , Einfeld Stewart L.
Published: September 2008

Sums of responses to behaviour checklist items are commonly used as outcome measures. We argue for the use of mean scores. For sets of responses registering absence and presence at different levels of intensity of behaviours we also show that mean scores may usefully be ‘decomposed’ into separate measures of the range and the intensity of problematic behaviours. These separate measures are the proportion of items positively endorsed and the ‘intensity index’ – the proportion of positive scores that are above one. We illustrate their use with primary outcome scores from the Developmental Behaviour Checklist (DBC) in the Australian Child to Adult Development Study. The low mean scores of young people with profound intellectual disability are shown to be a function of the narrow range of behaviours they display rather than of the level of intensity of these behaviours, which is relatively high. Change over time in mean scores is shown to be attributable to change in both the range and the intensity of behaviours as young people age in the study. We show how the technique of measuring these two separate strands contributing to mean scores may be applied to checklists with sets of responses longer than the zero, one, two of the DBC. Copyright © 2008 John Wiley & Sons, Ltd.
Psychometric properties of the World Health Organization Disability Assessment Schedule used in the European Study of the Epidemiology of Mental Disorders
Authors: Buist‐Bouwman M. A. , Ormel J. , De Graaf R. , Vilagut G. , Alonso J. , Van Sonderen E. , Vollebergh W. A. M. ,   The ESEMeD/MHEDEA 2000 Investigators
Published: September 2008

This study assessed the factor structure, internal consistency, and discriminatory validity of the World Health Organization Disability Assessment Schedule (WHODAS) version used in the European Study of the Epidemiology of Mental Disorders (ESEMeD). In total 8796 adults were assessed using the ESEMeD WHODAS (22 severity and 8 frequency items). An Exploratory Factor Analysis (EFA) with promax rotation was done with a random 50%. The other half was used for confirmatory factor analysis (CFA) comparing models (a) suggested by EFA; (b) hypothesized a priori; and (c) reduced with four items. A CFA model with covariates was conducted in the whole sample to assess invariance across Mediterranean (Spain, France and Italy) and non‐Mediterranean (Belgium, Germany and the Netherlands) countries. Cronbach's alphas and discriminatory validity were also examined. EFA identified seven factors (explained variance: 80%). The reduced model (six factors, four frequency items excluded) presented the best fit [Confirmatory Fit Index (CFI) = 0.992, Tucker–Lewis Index (TLI) = 0.996, Root Mean Square Error of Approximation (RMSEA) = 0.024]. The second‐order factor structure also fitted well (CFI = 0.987, TLI = 0.991, RMSEA = 0.036). Measurement non‐invariance was found for Embarrassment. Cronbach's alphas ranged from 0.84 for Participation to 0.93 for Mobility. Preliminary data suggest acceptable discriminatory validity. Thus, the ESEMeD WHODAS may well be a valuable shortened version of the WHODAS‐II, but future users should reconsider the filter questions. Copyright © 2008 John Wiley & Sons, Ltd.
Estimation of psycholeptic and psychoanaleptic medicine use in an adult general population sample using the Anatomical Therapeutic Chemical classification
Authors: John U. , Baumeister S. E. , Völzke H. , Grabe H. J. , Freyberger H. J. , Alte D.
Published: September 2008

Little is known about psycholeptic and psychoanaleptic medicine (PM) use in the general population. This study presents prevalence data about PM use. The sample included 4310 individuals aged 20–79 from a general population health examination in a northern German area (participation proportion: 68.8%; Study of Health in Pomerania, SHIP). Medicines taken during the past seven days were assessed from the medicine packages or self‐reports and classified according to the Anatomical Therapeutic Chemical (ATC) classification developed by the World Health Organization. In total, 6.3% of the sample reported PM intake, 8.7% of the women and 4.7% of the men. During the past 12 months prior to the health examination, 49.2% of the individuals with PM use consulted a general practitioner but not a neurologist or a psychiatrist. Among the study participants with PM use, 88.8% had one or more mental disorders during lifetime according to a screening questionnaire. It is concluded that considerable proportions of individuals with current PM use exist although lower than may be expected on the basis of the number of individuals with mental disorder in the general population. Copyright © 2008 John Wiley & Sons, Ltd.
Open to experience—closed to intelligence: Why the ‘Big Five’ are really the ‘Comprehensive Six’
Authors: Brand Chris R.
Published: September 2008

The quasi‐consensual ‘Big Five’ personality variables of the Five Factor Model (FFM) have typically been advanced and welcomed as dimensions that are purely orectic. By contrast, people's differences in general intelligence (g) are held to exist in some separate, noetic, cognitive ‘domain’. However, the exclusion of g from the realm of personality cannot be sustained either theoretically or empirically. The FFM's ‘fifth’ dimension (whether called Intellect (from lexical studies) or Openness (from questionnaire studies)) would be substantially correlated with g in the general population—across a normal population range of IQ and Mental Age. FFM fifth factors are thus loaded too highly by aesthetic, cultural, and theoretical interests, while qualities of tender‐mindedness, sympathy, and trust are displaced to load on the Agreeableness dimension. FFM Agreeableness thus becomes highly value‐loaded: it literally pits ‘love’, ‘empathy’, and ‘co‐operation’ against ‘aggression’, ‘autonomy’ and ‘competition’. No such simple contrast is viable. Social theorists as varied as Adam Smith, Freud, Adler, and Lorenz have all rejected the option. No fewer than six major, independent dimensions of personality require recognition. These ‘Comprehensive Six’ are (g), neuroticism/emotionality (n), energy/extraversion (e), conscientiousness/control (c), will/independence (w), and affection/pathemia (a). These are essentially the same as those recovered most often in the work of Cattell, so they furnish a six‐dimensional model (SDM) having a long track record of cross‐cultural validation. Several look interpretable in terms of basic Freudian concepts; and, in the terms of folk psychology, the SDM's ‘Comprehensive Six’ might be considered to reflect individual differences in the qualities of the mind (g), the heart (n), the soul (a), the spirit (e), the will (w), and the conscience (c).