bluuebunny/crossref_metadata_2025 huggingface dataset:
Antigen‐specific T‐cell activation in hyperplastic thymus in myasthenia gravis
Authors: Utsugisawa Kimiaki , Nagane Yuriko , Suzuki Shigeaki , Kondoh Ryushi
Published: April 2007

In order to determine whether antigen‐specific T‐cell activation by dendritic cells (DCs) is accelerated in thymuses exhibiting lymphofollicular hyperplasia (TLFH) among patients with early‐onset myasthenia gravis (EOMG), we investigated the expression levels of phosphorylated protein kinase C (PKC)θ and the local relationship between the presence of phosphorylated PKCθ and the homing receptor CD44 or CD83, a marker for mature DCs, in samples taken from EOMG patients with early improvement following thymectomy, in remnant thymuses from late‐onset MG patients, and in non‐MG control thymuses. Antigen‐specific T‐cell activation was markedly accelerated in TLFH from EOMG patients. Activated T cells and adjacent DCs appeared to be components of a CD44high cell population circulating from the blood to the thymus. Although there is no convincing evidence that thymectomy is of benefit in MG, in some EOMG patients with early improvement following thymectomy, blockade of CD44‐associated circulation mechanisms is probably the cause for the early benefits of thymectomy and is a potential alternative to thymectomy. Muscle Nerve, 2007
A moving‐mesh finite‐volume method to solve free‐surface seepage problem in arbitrary geometries
Authors: Darbandi M. , Torabi S. O. , Saadat M. , Daghighi Y. , Jarrahbashi D.
Published: April 2007

The main objective of this work is to develop a novel moving‐mesh finite‐volume method capable of solving the seepage problem in domains with arbitrary geometries. One major difficulty in analysing the seepage problem is the position of phreatic boundary which is unknown at the beginning of solution. In the current algorithm, we first choose an arbitrary solution domain with a hypothetical phreatic boundary and distribute the finite volumes therein. Then, we derive the conservative statement on a curvilinear co‐ordinate system for each cell and implement the known boundary conditions all over the solution domain. Defining a consistency factor, the inconsistency between the hypothesis boundary and the known boundary conditions is measured at the phreatic boundary. Subsequently, the preceding mesh is suitably deformed so that its upper boundary matches the new location of the phreatic surface. This tactic results in a moving‐mesh procedure which is continued until the nonlinear boundary conditions are fully satisfied at the phreatic boundary. To validate the developed algorithm, a number of seepage models, which have been previously targeted by the other investigators, are solved. Comparisons between the current results and those of other numerical methods as well as the experimental data show that the current moving‐grid finite‐volume method is highly robust and it provides sufficient accuracy and reliability. Copyright © 2007 John Wiley & Sons, Ltd.
Heuristic solutions for general concave minimum cost network flow problems
Authors: Fontes Dalila B.M.M. , Gonçalves José Fernando
Published: April 2007

We address the single‐source uncapacitated minimum cost network flow problem with general concave cost functions. Exact methods to solve this class of problems in their full generality are only able to address small to medium size instances, since this class of problems is known to be NP‐Hard. Therefore, approximate methods are more suitable. In this work, we present a hybrid approach combining a genetic algorithm with a local search. Randomly generated test problems have been used to test the computational performance of the algorithm. The results obtained for these test problems are compared to optimal solutions obtained by a dynamic programming method for the smaller problem instances and to upper bounds obtained by a local search method for the larger problem instances. From the results reported it can be shown that the hybrid methodology improves upon previous approaches in terms of efficiency and also on the pure genetic algorithm, i.e., without using the local search procedure. © 2007 Wiley Periodicals, Inc. NETWORKS, Vol. 50(1), 67–76 2007
Incremental flow
Authors: Hartline Jeff , Sharp Alexa
Published: April 2007

This paper defines an incremental version of the maximum flow problem. In this model, the capacities increase over time and the resulting solution is a sequence of flows that build on each other incrementally. Thus far, incremental problems considered in the literature have been built on NP‐complete problems. To the best of our knowledge, our results are the first to find a polynomial time problem whose incremental version is NP‐complete. We present approximation algorithms and hardness results for many versions of this problem, and comment on the relation to multicommodity flow. © 2007 Wiley Periodicals, Inc. NETWORKS, Vol. 50(1), 77–85 2007
Global microRNA profiles in cervical squamous cell carcinoma depend on Drosha expression levels
Authors: Muralidhar B , Goldstein LD , Ng G , Winder DM , Palmer RD , Gooding EL , Barbosa‐Morais NL , Mukherjee G , Thorne NP , Roberts I , Pett MR , Coleman N
Published: April 2007

Gain of chromosome 5p is seen in over 50% of advanced cervical squamous cell carcinomas (SCCs), although the genes responsible for the selective advantage provided by this abnormality are poorly understood. In the W12 cervical carcinogenesis model, we observed that 5p gain was rapidly selected over ∼15 population doublings and was associated with the acquisition of a growth advantage and invasiveness. The most significantly upregulated transcript following 5p gain was the microRNA (miRNA) processor Drosha. In clinically progressed cervical SCC, Drosha copy‐number gain was seen in 21/36 clinical samples and 8/10 cell lines and there was a significant association between Drosha transcript levels and copy‐number gain. Other genes in the miRNA processing pathway, DGCR8, XPO5 and Dicer, showed infrequent copy‐number gain and over‐expression. Drosha copy‐number and expression were not elevated in pre‐malignant cervical squamous intraepithelial lesions. Importantly, global miRNA profiling showed that Drosha over‐expression in cervical SCC appears to be of functional significance. Unsupervised principal component analysis of a mixed panel of cervical SCC cell lines and clinical specimens showed clear separation according to Drosha over‐expression. miRNAs most significantly associated with Drosha over‐expression are implicated in carcinogenesis in other tissues, suggesting that they regulate fundamental processes in neoplastic progression. Our evidence suggests that copy‐number driven over‐expression of Drosha and consequent changes in miRNAs are likely to be important contributors to the selective advantage provided by 5p gain in cervical neoplastic progression. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Single nucleotide polymorphism array analysis of chromosomal instability patterns discriminates rectal adenomas from carcinomas
Authors: Lips EH , de Graaf EJ , Tollenaar RAEM , van Eijk R , Oosting J , Szuhai K , Karsten T , Nanya Y , Ogawa S , van de Velde CJ , Eilers PHC , van Wezel Tom , Morreau H
Published: April 2007

Total mesorectal excision (TME) is the standard treatment for rectal cancer, while transanal endoscopic microsurgery (TEM) is a recently introduced surgical approach for the treatment of rectal adenomas. Incorrect preoperative staging before TEM is a problem. To identify genetic changes that might correlate with tumour stage and could lead to optimized treatment selection we performed a genome‐wide chromosomal instability search in a homogeneous, clinical cohort of rectal tumours. 78 rectal tumours during different clinical stages were analysed with 10K single nucleotide polymorphism (SNP) arrays. Logistic regression was performed to build a quantitative model of specific chromosomal aberrations. Overall, most cases (95%) had one or more chromosomal aberrations. We observed a clear correlation between the total number of aberrations and the different tumour stages. Specifically, the chromosomal events: gain of 8q22–24, 13q and 20q, and loss of 17p and 18q12–22, were far more abundant in carcinoma than in adenoma. In adenoma fractions from cases with a carcinoma (infiltrating at least in the submucosa), twice the amount of such ‘malignant aberrations’ was observed, compared to pure adenomas. Furthermore, combined aberrations such as gain of 13q and loss of 18q were only found in adenomatous fractions of carcinomas and not in benign lesions. Based on these five genomic events associated with carcinoma, a clear distinction between adenoma and carcinoma tissue could be made. These data should be validated further in order that they may be used in preoperative staging of rectal tumours. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Signet ring cell differentiation in mucinous colorectal carcinoma
Authors: Börger ME , Gosens MJEM , Jeuken JWM , van Kempen LCLT , van de Velde CJH , van Krieken JHJM , Nagtegaal ID
Published: April 2007

Approximately 10% of all colorectal carcinomas are mucinous carcinomas, characterized by extracellular mucin. Occasionally, mucin accumulates intracellularly in these tumours, causing signet ring cell differentiation. We hypothesized that signet ring cells arise from a separate genetic pathway. In this study the molecular background of signet ring cell differentiation was investigated by analysing genetic changes, changes in the expression of adhesion molecules, and mucin content. Furthermore, its clinical relevance was addressed.

Cell lines of colorectal tumours with non‐mucinous (AC), mucinous (MC), and signet ring cell phenotype (MCSRC) were used for Multiplex Ligation‐dependent Probe Amplification to detect deletions and amplifications in specific oncogenes and tumour suppressor genes. Furthermore, the expression of E‐cadherin, β‐catenin, ITF (intestinal trefoil factor), and MUC2 in signet ring cells was studied by immunohistochemistry, immunofluorescence, and mRNA in situ hybridization. Results were validated using a large cohort of rectal carcinomas from which clinicopathological data were available. Specific amplifications and deletions in cell lines of AC, MC, and MCSRC were detected. Bcl‐2 was amplified in MCSRC and MC cell lines, but not in AC cell lines. Bcl‐2 FISH analysis confirmed this in patient material.

Signet ring cells had decreased expression of adhesion molecules (E‐cadherin, β‐catenin) and were strongly positive for ITF and MUC2, two peptides which are normally only produced by goblet cells. RNA in situ hybridization confirmed the production of ITF. Mucinous carcinomas with signet ring cell differentiation presented at a higher T stage than adenocarcinomas and mucinous carcinomas (16% pT4 versus 3‐5%, p < 0.001) and were more frequently node positive (77% vs 39–44%; p < 0.001). Prognosis was significantly worse. In conclusion, the presence of signet ring cells in carcinomas with mucinous differentiation correlates with increased T‐stage and poor prognosis. These cells, characterized by ITF and MUC2 production, show disruption of the E‐cadherin/β‐catenin complex, as well as amplification of Bcl‐2. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
ADAM 12 as a second‐trimester maternal serum marker in screening for Down syndrome
Authors: Christiansen Michael , Spencer Kevin , Laigaard Jennie , Cowans Nicholas J. , Larsen Severin Olesen , Wewer Ulla M.
Published: April 2007

Background

ADAM 12 is a placenta‐derived glycoprotein that is involved in growth and differentiation. The maternal serum concentration of ADAM 12 is a potential first‐trimester maternal serum marker of Down syndrome (DS). Here we examine the potential of ADAM 12 as a second‐trimester maternal serum marker of DS.

Materials and Methods

The concentration of ADAM 12 was determined in gestational week 14–19 in 88 DS pregnancies and 341 matched control pregnancies. Medians of normal pregnancies were established by polynomial regression and the distribution of log10 MoM ADAM 12 values in DS pregnancies and controls determined. Correlations with alpha‐fetoprotein (AFP) and free β‐human chorionic gonadotrophin (free β‐hCG) were established and used to model the performance of maternal serum screening with ADAM 12 in combination with other second‐trimester serum markers.

Results

The ADAM 12 maternal serum concentration was significantly increased with a median MoM of 1.85 and a mean log10 MoM (SD) of 0.268 (0.2678) compared to a mean log10 MoM (SD) of 0.013 (0.4318) in controls. ADAM 12 correlated with maternal weight and ethnicity (with the serum concentration increased in Afro‐Caribbeans), but neither with maternal age nor gestational age, and only marginally with AFP (r(DS) = 0.078, r(controls) = 0.093) and free β‐hCG (r(DS) = 0.073, r(controls) = 0.144. The increase in detection rate—for a false positive rate of 5%—by adding ADAM 12 to the double test (AFP + free β‐hCG) was 4%, similar to that of adding uE3 to the double test.

Conclusion

ADAM 12 is an efficient second‐trimester marker for DS. Further studies should be conducted to determine whether it may be a useful additonal or alternative marker to those currently used in the second‐trimester. Copyright © 2007 John Wiley & Sons, Ltd.
Noticeable viscosity reduction of polycarbonate melts caused jointly by nano‐silica filling and TLCP fibrillation
Authors: Wu Li‐Chuan , Chen Peng , Chen Jun , Zhang Jun , He Jia‐Song
Published: April 2007

Nano‐SiO2 was introduced into in‐situ composites of polycarbonate (PC) and a thermotropic liquid crystalline polymer (TLCP) using a twin‐screw extruder. The rheology of these composites was characterized with capillary rheometry, and the morphology of the dispersed TLCP observed with scanning electron microscopy. The rheological data revealed that the viscosity decrease of PC melts by only the addition up to 20 wt% TLCP remained smaller than 30%, while it became ∼48% upon further addition of only about 1 wt% nano‐SiO2 and larger than 60% upon ∼9 wt% nano‐SiO2 filling, in contrast to a 50% viscosity increase of PC melts with increase in nanosilica loading up to ∼9 wt%. These silica‐filled composites exhibited markedly low viscosity, especially at relatively high shear rates. The morphology of TLCP extracted from unfilled and silica‐filled composites indicated that the largest viscosity reduction was correlated well with the fibrillation of TLCP droplets enhanced by nano‐SiO2. The TLCP/SiO2/PC composites exhibited rheological hybrid effect with fillers at nanometer scale. POLYM. ENG. SCI., 47:757–764, 2007. © 2007 Society of Plastics Engineers
Spatial orientation of nanoclay and crystallite in microcellular injection molded polyamide‐6 nanocomposites
Authors: Yuan Mingjun , Song Qing , Turng Lih‐Sheng
Published: April 2007

Three different types of characteristic structures‐microcells, nanoclay, and crystallite lamella‐exist in injection molded polyamide‐6 microcellular nanocomposites. These structures are in completely different scales. The spatial orientation of these microscale structures crucially determines the material's bulk properties. Based on scanning electron microscopy, transmission electron microscopy, and two‐dimensional X‐ray diffractometry measurements, it was found that the nanoclay and the crystallite formed special geometric structures around the microcells and near the part skins. The nanoclay platelets lay almost parallel to the surfaces of the molded parts. Preferred orientation of the crystallites was induced by the presence of the nanoclay. A molecular‐based model is proposed to describe the structural hierarchy and correlations among the microcells, nanoclay, and crystallite lamella. From the small‐angle X‐ray scattering experiments, it was found that microcellular injection molding produces relatively smaller crystallite lamella than that of conventional injection molding, and that for both solid and microcellular neat resin parts the crystallite lamella thickness at the part skin is smaller than that at the core. Polarized optical microscopy results also indicated that the size of crystallites in the microcellular neat resin and nanocomposite parts is smaller than that in the corresponding solid parts. POLYM. ENG. SCI., 47:765–779, 2007. © 2007 Society of Plastics Engineers
Optimization and scale‐up of starch cationization in a twin screw extruder
Authors: Berzin F. , Tara A. , Vergnes B.
Published: April 2007

In a previous work, a theoretical model for the cationization of wheat starch in a modular self‐wiping corotating twin screw extruder has been developed and experimentally validated. Our objective in the present article was to use this model in a first step to optimize the cationization reaction on a laboratory scale extruder, and, in a second step, to extrapolate the results to an industrial scale extruder. We will show that the use of a theoretical model of reactive extrusion allowed us to define screw profiles and processing conditions according to the end‐use properties of the desired product and the limits of the process. Based on the performances obtained at laboratory scale, it permitted also to predict the performances of an industrial production line. POLYM. ENG. SCI., 47:814–823, 2007. © 2007 Society of Plastics Engineers
Injection molding quality control by integrating weight feedback into a cascade closed‐loop control system
Authors: Chen Zhongbao , Turng Lih‐Sheng
Published: April 2007

Quality control plays a crucial role in injection molding control to meet stringent tolerance requirements and to facilitate automation. Previous work has tackled this challenging subject mainly through consistent machine operations or process variable control. In this paper, a direct quality feedback control system has been proposed and developed. The system has a cascade structure and combines both feedback and feedforward controls. An important quality index, namely, part weight, is measured in each molding cycle. The difference between this measurement and a quality target is used to adjust the mold separation at the process level. The mold separation is controlled via both a cycle‐to‐cycle mass‐based switchover point and a within‐cycle holding pressure control. Molding experiments have been conducted using different mold geometries and resins. Compared with the cavity pressure based control system currently used in industry, the control system in this study results in a significant improvement of both long‐term and short‐term consistencies in part quality. In addition, this direct quality feedback control has other benefits, such as 100% quality inspection and automatic process tuning. POLYM. ENG. SCI., 47:852–862, 2007. © 2007 Society of Plastics Engineers
Influence of the amount of salts of rosin acid on the nonisothermal crystallization, morphology, and properties of isotactic polypropylene
Authors: Wang Jingbo , Dou Qiang , Wu Shishan , Chen Xianyi
Published: April 2007

The nonisothermal crystallization of Isotactic polypropylene (iPP) containing different concentration of nucleating agent potassium dehydroabietate (DHAA‐K) or sodium dehydroabietate (DHAA‐Na) at the cooling rate of 10°C/min was investigated using differential scanning calorimetry (DSC) together with Jeziorny's method. It was found that the temperature at which the maximum rate of crystallization occurred shifted to a higher region by about 13.7–16.9°C, and the rate of crystallization became faster for iPP with DHAA‐K (PPK) or DHAA‐Na (PPNa) in comparison to the virgin iPP. Avrami exponent for virgin PP, PPK, and PPNa was about 3.1, 2.2, and 2.2, respectively, suggesting the change of the crystal growth mechanism of iPP with the addition of the nucleating agents. The morphology of iPP with and without nucleating agent examined by a cross polarized light microscope indicated that the size of spherulites marginally decreased, which then remained stable with the increase of the concentration of DHAA‐K or DHAA‐Na. The measurements of the optical and mechanical properties of iPP showed that the transparency, gloss, and flexural modulus increased with increasing nucleating agent before its optimal concentration. POLYM. ENG. SCI., 47:889–897, 2007. © 2007 Society of Plastics Engineers
Effect of melt annealing on the phase structure and rheological behavior of propylene–ethylene copolymers
Authors: De La Torre Vanesa , Fris Jorge A. Rodríguez , Failla Marcelo D. , Quinzani Lidia M.
Published: April 2007

The morphological and rheological properties of a commercial propylene‐ethylene copolymer (PEC) and a series of blends with different concentrations of poly (ethylene‐co‐propylene) are investigated. The blends are prepared mixing PEC with fractions obtained from it by solvent extraction. The phase structure of samples exposed to different thermal and mechanical histories was analyzed using scanning electron microscopy. The linear viscoelastic properties of the molten polymers were measured using different test sequences that include dynamic frequency and time sweeps. The phase structure of most blends changes dramatically with time when the polymers are kept in the molten state due to the coalescence of the domains. For example, the initial morphology of PEC which presents domains of ∼1 μm diameter changes to regions of more than 10 μm of average diameter after 90 min at 178°C at rest. Coincidentally, the dynamic moduli of the blends change during annealing reaching values that depend on the mechanical history. For example, the elastic modulus of PEC increases ∼32% during a dynamic time sweep of 45 min using a frequency of 0.1 s−1, while it decreases ∼18% when a frequency of 1 s−1 is applied. Moreover, the modulus measured at 0.1 s−1 of samples annealed at rest during 45 min is ∼58% larger than that of the fresh material. POLYM. ENG. SCI., 47:912–921, 2007. © 2007 Society of Plastics Engineers
Structure and properties of in situ compatibilized polystyrene/polyolefin elastomer blends
Authors: Guo Zhenghong , Tong Lifang , Xu Zhongbin , Fang Zhengping
Published: April 2007

To increase the compatibility of polystyrene (PS) and polyolefin elastomer (POE) blends, a Lewis acid catalyst, aluminum chloride (AlCl3), was adopted to initiate the Friedel–Crafts alkylation reaction for the formation of PS‐graft‐POE copolymer. Dynamic mechanical analysis indicated that PS/POE and PS/POE/AlCl3 blends are partially miscible, and the formation of PS‐graft‐POE copolymer increased the compatibility between PS and POE. Scanning electron microscope and transmission electron microscope results showed that the domain size of the blends decreased dramatically and the size distribution became more uniform with the addition of AlCl3. Such in situ compatibilization also induced hindrance to the macromolecular chain movement, as reflected by the results of the dynamic rheological analysis. The dynamic rheological behaviors of PS/POE and PS/POE/AlCl3 blends under different temperature showed that in situ compatibilization weakened the effects of thermooxidation on PS/POE blends. Moreover, in situ compatibilization decreased the activation energy of viscous flow and reduced the influence of temperature on PS/POE blends. POLYM. ENG. SCI., 47:951–959, 2007. © 2007 Society of Plastics Engineers
Effects of dam removal on brook trout in a Wisconsin stream
Authors: Stanley Emily H. , Catalano Matt J. , Mercado‐Silva Norman , Orr Cailin H.
Published: April 2007

Dams create barriers to fish migration and dispersal in drainage basins, and the removal of dams is often viewed as a means of increasing habitat availability and restoring migratory routes of several fish species. However, these barriers can also isolate and protect native taxa from aggressive downstream invaders. We examined fish community composition two years prior to and two years after the removal of a pair of low‐head dams from Boulder Creek, Wisconsin, U.S.A. in 2003 to determine if removal of these potential barriers affected the resident population of native brook trout (Salvelinus fontinalis). Despite the presence of other taxa in the downstream reaches, and in other similar streams adjacent to the Boulder Creek (including the brown trout, Salmo trutta), no new species had colonized the Boulder Creek in the two years following dam removal. The adults catch per unit effort (CPUE) was lower and the young‐of‐the‐year catch per unit effort (YOY CPUE) was higher in 2005 than in 2001 in all reaches, but the magnitude of these changes was substantially larger in the two dam‐affected sample reaches relative to an upstream reference reach, indicating a localized effect of the removal. Total length of the adults and the YOY and the adult body condition did not vary between years or among reaches. Thus, despite changes in numbers of adults and the YOYs in some sections of the stream, the lack of new fish species invading Boulder Creek and the limited extent of population change in brook trout indicate that dam removal had a minor effect on these native salmonids in the first two years of the post‐removal. Copyright © 2007 John Wiley & Sons, Ltd.
Comparative characterisation by atomic force microscopy and ellipsometry of soft and solid thin films
Authors: Mykhaylyk T. A. , Dmitruk N. L. , Evans S. D. , Hamley I. W. , Henderson J. R.
Published: April 2007

Ellipsometry and atomic force microscopy (AFM) were used to study the film thickness and the surface roughness of both ‘soft’ and solid thin films. ‘Soft’ polymer thin films of polystyrene and poly(styrene–ethylene/butylene–styrene) block copolymer were prepared by spin‐coating onto planar silicon wafers. Ellipsometric parameters were fitted by the Cauchy approach using a two‐layer model with planar boundaries between the layers. The smooth surfaces of the prepared polymer films were confirmed by AFM. There is good agreement between AFM and ellipsometry in the 80–130 nm thickness range. Semiconductor surfaces (Si) obtained by anisotropic chemical etching were investigated as an example of a randomly rough surface. To define roughness parameters by ellipsometry, the top rough layers were treated as thin films according to the Bruggeman effective medium approximation (BEMA). Surface roughness values measured by AFM and ellipsometry show the same tendency of increasing roughness with increased etching time, although AFM results depend on the used window size. The combined use of both methods appears to offer the most comprehensive route to quantitative surface roughness characterisation of solid films. Copyright © 2007 John Wiley & Sons, Ltd.
Analysis of cluster ion sputtering yields: correlation with the thermal spike model and implications for static secondary ion mass spectrometry
Authors: Seah M. P.
Published: April 2007

An assessment is made of the behaviours in ion sputtering and static secondary ion mass spectrometry to provide a framework to understand the enhanced secondary ion yield of molecular fragments, from molecules on defined substrates, achieved by using primary ion clusters. First, an analysis is made of the published ion sputtering yield data for mono‐elemental solids sputtered by mono‐elemental primary ion clusters, mainly of the type Aun+. These are evaluated using Sigmund and Claussen's thermal spike model. That theory is shown to be consistent with, and an excellent description of, the published ion sputtering yields for elemental targets over a wide energy range for primary ion cluster sizes from 1 to 13 for gold primary ion clusters and for a number of different primary ion species. This theory is then used to evaluate the molecular ion yield behaviour of interest in static secondary ion mass spectrometry (SIMS). This is done for measurements on Irganox 1010. The thermal spike sputtering yield is first related to the total secondary ion yield. The secondary ion yield of the molecular ion, whether protonated or de‐protonated, is then shown to be proportional to the square of the total secondary ion yield and hence to the square of the sputtering yield. This rule is valid for all primary ions, both single atom and cluster, over 5 decades of emission intensity, largely independent of the chemical identity of the primary ions for those data. This enables recommendations for future sources of higher efficiency for the analysis of organic materials. © Crown copyright 2007. Reproduced with the permission of Her Majesty's Stationery Office. Published by John Wiley & Sons, Ltd.
Seilnetze – Eigenschaften, Besonderheiten bei der Montage, Lastabtragung
Authors: Ströbel Dieter , Singer Peter , Oswald Rudi
Published: April 2007

Seilnetze besitzen eine große Flexibilität im Bauen von dreidimensionalen Flächen. Die Vorteile von Seilnetzen aus Stahl sind, dass die Stahlseile einen großen Widerstand gegen Beschädigung und mutwillige Zerstörung besitzen, aufgrund des hohen Anprallwiderstandes als Absturzsicherung oder Absperrung dienen und eine sehr große Transparenz aufweisen. Mit Seilnetzen werden heute weltweit Geländerausfachungen, Absturzsicherungen an Bauten, Fassaden, Tiergehege und Gartenmöbel gebaut. Die Seilnetze finden für die Innenraumgestaltungen bei Messen und Ausstellungen zunehmend Interesse. Dargestellt werden die Eigenschaften der Seilnetze, die Besonderheiten bei der Montage und ihre Lastabtragung. Die Kinematik der Vierecksmaschen ist die Ursache für die freie Formbarkeit der Netze. Für die ingenieurtechnische Erfassung der Netze ist es erforderlich, dass Methoden zur Verfügung gestellt werden, die eine Berechnung der Gleichgewichtsflächen ermöglichen, das Verhalten der Seilnetze unter äußeren Einwirkungen und unter Berücksichtigung der Vorspannung beschreiben und den Prozess des Montageprozesses erfassen.
Ein orthotropes Werkstoffgesetz für Folien
Authors: Karwath Michael , Wagner Rosemarie , Kröplin Bernd
Published: April 2007

Folien besitzen, bedingt durch den Herstellungsprozess, ein orthotropes Tragverhalten, das im Allgemeinen bisher nicht berücksichtigt wurde. In diesem Beitrag wird eine Theorie vorgestellt, um die Werkstoffkenngrößen für einen beliebigen ebenen Spannungszustand zu ermitteln und ein experimenteller Weg angegeben, um diese zu verifizieren. Damit wird die Voraussetzung geschaffen, die Lastabtragung in Membranbauten wesentlich genauer vorherzusagen, als dies bisher möglich ist.
Zuschriften zu: Peil, U., Steiln, O.: Regen‐Wind‐induzierte Schwingungen – ein State‐of‐the‐Art‐Report
Authors: Peil Udo , Steiln Oliver
Published: April 2007

[Stahlbau 76 (2007), H. 1, S. 34–46, 10.1002/stab.200710005]
Decision‐Making About Reproductive Choices Among Individuals At‐Risk for Huntington's Disease
Authors: Klitzman Robert , Thorne Deborah , Williamson Jennifer , Chung Wendy , Marder Karen
Published: April 2007

We explored how individuals at‐risk for HD who have or have not been tested make reproductive decisions and what factors are involved. We interviewed 21 individuals (8 with and 4 without the mutation, and 9 un‐tested) in‐depth for 2 hours each. At‐risk individuals faced a difficult series of dilemmas of whether to: get pregnant and deliver, have fetal testing, have pre‐implantation genetic diagnosis, adopt, or have no children. These individuals weighed competing desires and concerns: their own desires vs. those of spouses vs. broader moral concerns (e.g., to end the disease; and/or follow dictates against abortion) vs. perceptions of the interests of current or future offspring. Quandaries arose of how much and to whom to feel responsible. Some changed their perspectives over time (e.g., first “gambling,” then being more cautious). These data have critical implications for genetic counselors and other health care workers and future research, particularly as more genetic tests become available.
The Location of Phenolic Antioxidants and Radicals at Interfaces Determines Their Activity
Authors: Heins Anja , McPhail Donald B. , Sokolowski Tobias , Stöckmann Heiko , Schwarz Karin
Published: April 2007

To characterize parameters influencing the antioxidant activity at interfaces a novel ESR approach was developed, which facilitates the investigation of the reaction stoichiometry of antioxidants towards stable radicals. To relate the activity of antioxidants towards the location of radicals at interfaces NMR experiments were conducted. Micellar solutions of SDS, Brij and CTAB were used to model interfaces of different chemical nature. The hydrophilic Fremy's radical was found to be solubilized exclusively in the aqueous phase of SDS micellar solution but partitioned partly into the hydrophilic headgroup area of Brij micelles. In contrast the hydrophobic galvinoxyl was exclusively located in the micellar phase with the increasing depth of intercalation in the order SDS < Brij < CTAB. Gallates revealed a higher stoichiometric factor towards galvinoxyl in CTAB systems, which is accounted to a concentration effect of antioxidant and radical being both solubilized in the palisade layer. In contrast, in SDS solutions hardly any reaction between galvinoxyl and gallates was found. SDS acted as a physical barrier between radical (palisade layer) and antioxidant (stern layer). The influence of the hydrophobic properties of the antioxidant was clearly seen in Brij micelles. Elongation of the alkyl chain in gallate molecule resulted in increasing stoichiometric factors in the presence of galvinoxyl being located in the deeper region of the bulky headgroup area. The reverse trend was found in the presence of Fremy's radical being located in the hydrated area of the micelles.
Impact of heart rate on mechanical dyssynchrony and left ventricular contractility in patients with heart failure and normal QRS duration
Authors: Kurita Tairo , Onishi Katsuya , Dohi Kaoru , Tanabe Masaki , Fujimoto Naoki , Tanigawa Takashi , Setsuda Morimichi , Isaka Naoki , Nobori Tsutomu , Ito Masaaki
Published: April 2007

Aims:

The quantification of mechanical dyssynchrony has important diagnostic value and may help to determine optimal therapy in heart failure (HF). We hypothesized that mechanical dyssynchrony may be augmented at increased heart rates in patients with HF and normal QRS duration.

Methods and results:

From online segmental conductance catheter signals, we derived indices to quantify temporal and spatial aspects of mechanical dyssynchrony during systole in 20 control subjects, 20 HF patients with normal QRS duration, and 12 HF patients with complete left bundle branch block (CLBBB). Data were collected at baseline, and then following a 40 bpm increase in heart rate induced by right atrial pacing. Mechanical dyssynchrony in HF patients with normal QRS duration or CLBBB was higher than that found in control subjects. In HF patients with normal QRS duration, mechanical dyssynchrony increased from 37.4±4.8% at baseline to 43.2±4.4% with increased heart rate (p<0.01), the resultant degree of mechanical dyssynchrony was similar to that at baseline in the HF patients with CLBBB. Increased heart rate did not affect dyssynchrony in the control patients.

Conclusion:

Mechanical dyssynchrony was augmented as heart rate increased by right atrial pacing in patients with HF and normal QRS duration.
The Evidence for Physiologic Management of the Active Phase of the First Stage of Labor
Authors: Albers Leah L.
Published: April 2007

The active phase of first stage labor is generally defined as the period between 3 cm to 4 cm to complete cervical dilatation, in the presence of regular uterine contractions. Most women will experience this portion of labor within hospital obstetric units, where care commonly features restriction to bed, electronic fetal monitoring, early treatment of “slow” labors, and few pain management options beyond epidurals and narcotics. However, the available evidence on appropriate care for healthy childbearing women favors activity in labor, intermittent auscultation, patience from caregivers, and nonpharmacologic methods of pain relief. This article reviews the evidence for care practices that support physiologic labor. Modifying intrapartum care to reflect current evidence will improve women's health, and will require a multilevel approach and consistent midwifery demonstration of the model.
Management of the Third Stage of Labor
Authors: McDonald Susan
Published: April 2007

Management of the third stage of labor has been an issue of discussion, concern, and continued debate for the past two decades. Despite the many strategies employed and the divergent approaches to care and philosophies espoused, there has not been a significant, consistent reduction in the postpartum hemorrhage rates reported in industrialized countries in recent times. This article explores the strategies that have been and are currently being used in an effort to reduce the risk of postpartum hemorrhage.
Hygienic quality of ewes' milk cheeses manufactured with artisan-produced lamb rennet pastes
Authors: Gil Pilar F , Conde Socorro , Albisu Marta , Pérez-Elortondo Francisco J , Etayo Iñaki , Virto Mailo , de Renobales Mertxe
Published: April 2007

The use of artisan-produced lamb rennet pastes, but not any of the other commercial animal rennets, imparts a characteristic flavour to the cheese, so most Mediterranean ewes' milk cheeses are coagulated with this kind of rennet paste. In contrast to the advantages of using lamb or kid rennet pastes from the sensory point of view, questions are still raised as to their hygienic quality. The goal was to examine the microbiological and enzymic quality of lamb rennet pastes prepared by cheese manufacturers for their own use, and evaluate the hygienic quality of raw sheeps' milk cheeses made with them, using Idiazabal cheese as a model. Lamb rennet pastes prepared by artisan cheese makers from the Basque region of Spain (27), and Italy (8) were evaluated. For cheese making experiments 5 different lamb rennet pastes were selected among the 27 samples from the Basque Country region of Spain. Microbiological analyses were carried out on samples from rennet pastes, rennet extracts, milks and cheeses during ripening. Enzymic activities studied in rennet paste were: total coagulating strength and lipase. Analysis of variance and Student's t-tests was performed. The results show that the artisan-produced rennet pastes contain high levels of a variety of microorganisms. After 60 ripening days, which is the minimum ripening period required for Idiazabal cheese prior to its commercialization, no Eschericia coli, Clostridium, Salmonella spp. or Listeria monocytogenes were detected, and levels for the rest of the microorganisms were below the limits of the European legislative standards for cheese manufactured with raw milk. We can conclude that the use of artisan-produced lamb rennet pastes of questionable hygienic quality for the manufacture of raw milk hard cheeses yields products of good hygienic quality.
Development of a monoclonal antibody-based immunoassay for specific quantification of bovine milk alkaline phosphatase
Authors: Geneix Nathalie , Dufour Eric , Venien Annie , Levieux Didier
Published: April 2007

The detection of alkaline phosphatase (ALP) activity is used as a legal test to determine whether milk has been adequately pasteurized or recontaminated with raw milk. However, a wide variety of microorganisms produce both heat labile and heat stable ALPs which cannot be differentiated from the milk ALP by current enzymatic methods. Monoclonal antibodies specific of the bovine milk ALP were obtained in mice from a raw bovine milk ALP preparation. Coated in microtitre plates, these antibodies specifically capture the bovine milk ALP from dairy products. After washing, the enzymatic activity of the captured ALP is revealed by addingp-nitrophenyl-phosphate as a substrate. This simple immunoassay does not react with ALPs of intestinal or bacterial origin and, once optimized, was found to be the first immunoassay suitable to detect raw milk in boiled milk down to a 0·02% dilution. Moreover, in contrast with competitive indirect ELISA formats, the capture immunoassay does not require purified ALP.
Nutritional management of gut health in pigs around weaning
Authors: Lallès Jean-Paul , Bosi Paolo , Smidt Hauke , Stokes Chris R.
Published: April 2007

Early weaning of piglets is often accompanied by a severe growth check and diarrhoea. It is well established that this process is multi-factorial and that post-weaning anorexia and undernutrition are major aetiological factors. Gastrointestinal disturbances include alterations in small intestine architecture and enzyme activities. Recent data indicate transiently-increased mucosal permeability, disturbed absorptive–secretory electrolyte balance and altered local inflammatory cytokine patterns after weaning. These responses appear to operate according to two distinct temporal patterns, an acute response followed by a long-lasting adaptation response. Pigs coexist with a diverse and dense commensal microbiota in their gastrointestinal tract. Most of these microbes are beneficial, providing necessary nutrients or protection against harmful pathogens for the host. The microbial colonisation of the porcine intestine begins at birth and follows a rapid succession during the neonatal and weaning period. Following the withdrawal of sow's milk the young piglets are highly susceptible to enteric diseases partly as a result of the altered balance between developing beneficial microbiota and the establishment of intestinal bacterial pathogens. The intestinal immune system of the newborn piglet is poorly developed at birth and undergoes a rapid period of expansion and specialisation that is not achieved before early (commercial) weaning. Here, new insights on the interactions between feed components, the commensal microbiota and the physiology and immunology of the host gastrointestinal tract are highlighted, and some novel dietary strategies are outlined that are focused on improving gut health. Prebiotics and probiotics are clear nutritional options, while convincing evidence is still lacking for other bioactive substances of vegetable origin.
Internet-based cognitive behavioural therapy for subthreshold depression in people over 50 years old: a randomized controlled clinical trial
Authors: SPEK VIOLA , NYKLÍČEK IVAN , SMITS NIELS , CUIJPERS PIM , RIPER HELEEN , KEYZER JULES , POP VICTOR
Published: April 2007

Background

Subthreshold depression is a highly prevalent condition and a risk factor for developing a major depressive episode. Internet-based cognitive behaviour therapy may be a promising approach for the treatment of subthreshold depression. The current study had two aims: (1) to determine whether an internet-based cognitive behaviour therapy intervention and a group cognitive behaviour therapy intervention are more effective than a waiting-list control group; and (2) to determine whether the effect of the internet-based cognitive behaviour therapy differs from the group cognitive behaviour therapy intervention.

Method

A total of 191 women and 110 men with subthreshold depression were randomized into internet-based treatment, group cognitive behaviour therapy (Lewinsohn's Coping With Depression course), or a waiting-list control condition. The main outcome measure was treatment response after 10 weeks, defined as the difference in pre- and post-treatment scores on the Beck Depression Inventory (BDI). Missing data, a major limitation of this study, were imputed using the Multiple Imputation (MI) procedure Data Augmentation.

Results

In the waiting-list control group, we found a pre- to post-improvement effect size of 0·45, which was 0·65 in the group cognitive behaviour therapy condition and 1·00 within the internet-based treatment condition. Helmert contrasts showed a significant difference between the waiting-list condition and the two treatment conditions (p=0·04) and no significant difference between both treatment conditions (p=0·62).

Conclusions

An internet-based intervention may be at least as effective as a commonly used group cognitive behaviour therapy intervention for subthreshold depression in people over 50 years of age.
Exploring the inter-relationship of smoking age-at-onset, cigarette consumption and smoking persistence: genes or environment?
Authors: MORLEY KATHERINE I. , LYNSKEY MICHAEL T. , MADDEN PAMELA A. F. , TRELOAR SUSAN A. , HEATH ANDREW C. , MARTIN NICHOLAS G.
Published: April 2007

Background

We investigated the genetic and environmental contributions to covariation between smoking age-at-onset, cigarette consumption and smoking persistence.

Method

Multivariate biometrical modelling methods were applied to questionnaire data from Australian twins and their siblings (14 472 individuals from 6247 families). The contributions of genetic and environmental factors to covariation between the three traits were estimated, allowing for sex differences in both trait prevalence and the magnitude of genetic and environmental effects.

Results

All traits were moderately heritable in males and females (estimates between 0·40 and 0·62), but there were sex differences in the extent to which additive genetic influences were shared across traits. Twin-specific environmental factors accounted for a substantial proportion of the variance in smoking age-at-onset in females (0·19) and males (0·12), but had little influence (<0·08) on other traits. Unique environmental factors were estimated to have a moderate influence on smoking age-at-onset (0·17 for females, 0·19 for males), but a stronger influence on other traits (between 0·39 and 0·49).

Conclusions

These results provide some insight into observed sex differences in smoking behaviour, and suggest that searching for pleiotropic genes may prove fruitful. However, further work on phenotypic definitions of smoking behaviour, particularly persistence, is warranted.
SOCIAL CHOICE AND JUST INSTITUTIONS: NEW PERSPECTIVES
Authors: FLEURBAEY MARC
Published: April 2007

It has become accepted that social choice is impossible in the absence of interpersonal comparisons of well-being. This view is challenged here. Arrow obtained an impossibility theorem only by making unreasonable demands on social choice functions. With reasonable requirements, one can get very attractive possibilities and derive social preferences on the basis of non-comparable individual preferences. This new approach makes it possible to design optimal second-best institutions inspired by principles of fairness, while traditionally the analysis of optimal second-best institutions was thought to require interpersonal comparisons of well-being. In particular, this approach turns out to be especially suitable for the application of recent philosophical theories of justice formulated in terms of fairness, such as equality of resources.
A NOTE ON CONDITIONAL EGALITARIANISM
Authors: HOLTUG NILS
Published: April 2007

Roughly, according to conditional egalitarianism, equality is non-instrumentally valuable, but only if it benefits at least one individual. Some political theorists have argued that conditional egalitarianism has the important virtue that it allows egalitarians to avoid the so-called ‘levelling down’ objection. However, in the present article I argue that conditional egalitarianism does not offer the egalitarian a plausible escape route from this objection. First, I explain the levelling down objection and suggest some particular concerns from which it derives its force. Then I provide a more precise definition of conditional egalitarianism. Finally, I give two arguments against this principle. According to the first, it violates the transitivity of the betterness relation (or more specifically, ‘betterness with respect to equality’). According to the second, there is no plausible explanation of why equality must benefit at least one individual in order to be non-instrumentally valuable.