bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhanced secretion of prostaglandin E2 from osteoblasts by exposure to a strong static magnetic field
Authors: Sakurai Tomonori , Terashima Shingo , Miyakoshi Junji 
Published: December 2007

AbstractExposure to static magnetic fields (SMFs) has been reported to promote osteoblast differentiation in vitro, and increase bone formation in vivo and in clinical studies. Prostaglandins respond early to exogenous mechanical loading, and play an important role in bone formation. In this study, we investigated whether exposure to a strong SMF affects prostaglandin E2 (PGE2) secretion from a mouse osteoblastic cell line, MC3T3‐E1. We also investigated the PGE2‐synthesizing enzyme, cyclooxygenase 2 (Cox‐2), and translocation of the transcription factor nuclear factor kappa B (NF‐κB), which is involved in the induction of Cox‐2 expression. In the SMF exposures, experiments were performed at the 10 T‐exposure position, at which the magnetic flux density was highest, and at the 6 T‐exposure position, at which the magnetic field gradient was highest (41.7 T/m). PGE2 secretion was not affected by exposure at the 10 T‐exposure position compared to sham‐exposure, but was enhanced at the 6 T‐exposure position (about 1.5‐fold). Similarly, Cox‐2 expression and NF‐κB translocation were not enhanced at the 10 T‐exposure position, but increased at the 6 T‐exposure position (about twofold, two‐ to threefold, respectively). These findings suggested that exposure to a high magnetic field gradient induced secretion of PGE2 and expression of the Cox‐2 protein, which was mediated through increased translocation of NF‐κB. Bioelectromagnetics 29:277–283, 2008. © 2007 Wiley‐Liss, Inc.
Psychomotor performance is not influenced by brief repeated exposures to mobile phones
Authors: Curcio G. , Valentini E. , Moroni F. , Ferrara M. , De Gennaro L. , Bertini M. 
Published: December 2007

AbstractThe present study investigated the presence of a cumulative effect of brief and repeated exposures to a GSM mobile phone (902.40 MHz, 217 Hz modulated; peak power of 2 W; average power of 0.25 W; SAR = 0.5 W/kg) on psychomotor functions. To this end, after each of 3 15‐min exposures, both an acoustic simple reaction time task (SRTT) and a sequential finger tapping task (SFTT) were administered to 24 subjects. The present study was unable to detect the cumulative effects of brief and repeated EMF exposure on human psychomotor performance, although there was a non‐statistical trend to shorter reaction times. In summary, these data show an absence of effects with these particular exposure conditions; however, possible cognitive effects induced by different signal characteristics cannot be excluded. Bioelectromagnetics 29:237–241, 2008. © 2007 Wiley‐Liss, Inc.
Comparison of outcomes of ileal pouch–anal anastomosis for familial adenomatous polyposis with and without previous ileorectal anastomosis
Authors: von Roon A C , Tekkis P P , Lovegrove R E , Neale K F , Phillips R K S , Clark S K 
Published: December 2007

Abstract

Background
It is reported that previous colectomy and ileorectal anastomosis (IRA) has no effect on postoperative complications and functional outcomes of secondary proctectomy and ileal pouch–anal anastomosis (IPAA) in patients with familial adenomatous polyposis (FAP). This retrospective study re-examined the question in a single centre.

Methods
Some 185 patients were grouped by either IPAA as the initial prophylactic surgical procedure (primary IPAA) or IPAA preceded by IRA (secondary IPAA). Data on functional outcomes were available for 104, 83 and 56 patients at years 1, 5 and 10 respectively.

Results
The 78 patients who had secondary IPAA were older at the time of operation than the 107 who underwent primary IPAA (35·7 versus 29·2 years; P &lt; 0·001). Six (8 per cent) of the secondary IPAA procedures could not be completed. Otherwise, apart from more wound infections in the secondary IPAA group (9 versus 0·9 per cent in the primary IPAA group; P = 0·012), there were no significant differences in rates of complications, functional outcomes, desmoid disease or pouch failure.

Conclusion
Conversion from IRA to IPAA may not be possible in patients with FAP. Where conversion is successful, pouch outcomes are similar but wound infections are more frequent.
Management of concomitant hepatic artery injury in patients with iatrogenic major bile duct injury after laparoscopic cholecystectomy
Authors: Li J , Frilling A , Nadalin S , Paul A , Malagò M , Broelsch C E 
Published: December 2007

Abstract

Background
Concomitant hepatic artery injury is a rare but severe complication associated with bile duct injury during laparoscopic cholecystectomy (LC).

Methods
Sixty patients referred with biliary injury after LC between April 1998 and December 2005 were divided into two groups according to the time elapsed between injury and definitive surgical revision; patients in group 1 were referred early (within 4 days) after operation and those in group 2 were referred later. Hepatic rearterialization was performed in addition to biliary reconstruction when technically possible.

Results
Damage to the hepatic artery was detected in ten patients. Hepatic rearterialization was carried out in five patients by end-to-end anastomosis (one), or by using an autologous graft (three) or allogeneic vascular graft (one). Three patients in group 2 underwent right hemihepatectomy without arterial reconstruction owing to liver necrosis or lobar atrophy. Three of ten patients died from postoperative complications.

Conclusion
Combined bile duct and hepatic artery injury during LC led to a complicated clinical course, with a high mortality rate. Reconstruction of the right hepatic artery might be helpful in reducing hepatic ischaemia, but is usually feasible only if the injury is identified early.
Length of follow-up after fistulotomy and fistulectomy associated with endorectal advancement flap repair for fistula in ano
Authors: Ortiz H , Marzo M , de Miguel M , Ciga M A , Oteiza F , Armendariz P 
Published: December 2007

Abstract

Background
The length of follow-up required after surgical repair of cryptoglandular fistula in ano has not been established. This prospective study determined the follow-up time needed to establish that an anal fistula has been cured after elective fistulotomy or fistulectomy associated with endorectal advancement flap (ERAF) repair.

Methods
Between January 2001 and June 2004, consecutive patients with anal fistula of cryptoglandular aetiology were included provided that they lived within the catchment area of the hospital and agreed to participate in a follow-up programme, which comprised scheduled visits every month until complete wound healing and annually thereafter.

Results
Some 206 of 219 eligible patients were evaluable; fistulotomy was performed in 115 and ERAF repair in 91. Median follow-up was 42 (range 24–65) months. Eighteen patients had recurrence of the fistula during follow-up, with a median time to relapse of 5·0 (range 1·0–11·7) months. There were no recurrences after 1 year.

Conclusion
Recurrence of fistula in ano of cryptoglandular origin treated by means of fistulotomy or ERAF repair occurs within the first year of operation.
Detoxification enzyme polymorphisms are not involved in duodenal adenomatosis in familial adenomatous polyposis
Authors: Berkhout M , Roelofs H M J , te Morsche R H M , Dekker E , van Krieken J H J M , Nagengast F M , Peters W H M 
Published: December 2007

Abstract

Background
Patients with familial adenomatous polyposis (FAP) are at high risk of developing duodenal adenomas and carcinomas. Besides germline mutations in the adenomatous polyposis coli (APC) gene, additional factors may influence the age of onset and number of duodenal adenomas. This study compared the genotype distributions of duodenal detoxification enzyme isoforms in patients with FAP and controls.

Methods
The study included 85 patients with FAP and 218 healthy age- and sex-matched controls. Genotyping of all participants using polymerase chain reaction was performed to detect polymorphisms in isoforms of uridine 5′-diphosphate glucuronosyltransferases (UGTs) and glutathione S-transferases (GSTs): UGT1A1, UGT1A3, UGT1A4, UGT1A6, UGT1A10, UGT2B4, UGT2B7, UGT2B15, GSTA1, GSTP1, GSTM1 and GSTT1.

Results
The variant genotypes of UGT1A3 were less common in patients with FAP than in controls (odds ratio 0·39 (95 per cent confidence interval 0·22 to 0·67)). There were no associations between FAP and the other polymorphic genes. The polymorphisms investigated had no predictive value for the severity of duodenal adenomatosis in patients with FAP.

Conclusion
Although the variant genotypes of UGT1A3 were less common in patients with FAP than in those without, this did not modulate the severity of duodenal adenomatosis.
Carbohydrate antigen 19·9 accurately selects patients for laparoscopic assessment to determine resectability of pancreatic malignancy
Authors: Halloran C M , Ghaneh P , Connor S , Sutton R , Neoptolemos J P , Raraty M G T 
Published: December 2007

Abstract

Background
Laparoscopy with laparoscopic ultrasonography (L–LUS) may be useful in the selection of patients for surgery to resect peripancreatic malignancy in addition to contrast-enhanced computed tomography (CE–CT). The present prospective study assessed the strategy of using carbohydrate antigen 19·9 (CA19·9) levels to select patients for L–LUS.

Methods
Patients with suspected peripancreatic malignancy that appeared resectable on CE–CT were selected for immediate surgery if CA19·9 was low (up to 150 kU/l, or up to 300 kU/l if serum bilirubin was above 35 µmol/l), or to L–LUS if CA19·9 was high (over 150 kU/l, or over 300 kU/l if serum bilirubin was above 35 µmol/l). Data were assessed to determine the clinical utility of this strategy.

Results
A total of 94 patients went straight to surgery, of whom 65 proved resectable: 63 of 80 with a low CA19·9 level but only two of 14 with a high CA19·9 level and gastric outlet obstruction. From 55 patients with high CA19·9 levels, L–LUS correctly identified 26 of 31 resectable tumours and eight of 24 unresectable tumours.

Conclusion
Using CA19·9 levels to help select patients with pancreatic malignancy for immediate surgery or L–LUS for further assessment of resectability effectively increased resection rates and reduced unnecessary laparotomies.
Letter 1: Functional results after extended myotomy for diffuse oesophageal spasm (Br J Surg 2007; 94: 1113–1118)
Authors: Storr M 
Published: December 2007

Abstract
The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses should be sent electronically via the BJS website (www.bjs.co.uk). All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length.
Solubility Calculation of Oil‐Conta‐minated Drill Cuttings in Supercritical Carbon Dioxide Using Statistical Associating Fluid Theory (PC‐SAFT)
Authors: Esmaeilzadeh F. , Goodarznia I. , Daneshi R. 
Published: December 2007

AbstractSupercritical fluid extraction is a new technology that could be effectively used to treat oil‐contaminated drill cuttings generated during drilling for oil and gas. In this work, the solubility of oil‐contaminated drill cuttings in supercritical carbon dioxide is obtained by an experimental flow type apparatus. The solubility was measured at 200 bar pressure, over a temperature range of 55–79.5 °C. The measured solubility and experimental data for oil in drill cuttings were correlated using the PC‐SAFT, PR and SRK EOS models, without any adjustable parameters. Average absolute derivations of less than 15.1 %, 98.7 %, and 99.3 % are achieved between predicted and experimental values for the PC‐SAFT, PR and SRK EOS models, respectively, over a wide range of temperatures.
Modification of Nafion Membranes by Impregnation with Ionic Liquids
Authors: Schmidt C. , Glück T. , Schmidt‐Naake G. 
Published: December 2007

AbstractNafion 117 membranes were impregnated with various imidazolium (1‐hexyl‐3‐methyl‐imidazolium/HMI, 1‐butyl‐3‐methyl‐imidazolium/BMI) and pyrrolidinium (1‐butyl‐1‐methyl‐pyrrolidinium/BMPyr) based ionic liquids bearing hydrophobic (tris(pentafluoroethyl)trifluorophosphate/FAP, bis(trifluoromethylsulfonyl)imide/BTSI, hexafluorophosphate/PF6) and more hydrophilic (tetrafluoroborate/BF4) anions. The modified membranes were characterized in terms of uptake behavior, washing out of the ionic liquids by water, swelling in humidified environment, thermal stability, mechanical properties, ion exchange capacity and ion conductivity. Upon this treatment, the ionic liquids' cations partially replace the protons of the sulfonic acid groups in Nafion. While the ionic liquids act as potent plasticizers in the polymer matrix, thermal stability of these systems remains unchanged and swelling by water of the dried ionomer membranes is reduced. Ion conductivities at 120 °C under dry conditions have been found to be up to 100 times higher than for dry Nafion 117. In particular, modification of Nafion by ionic liquids bearing the bulky hydrophobic FAP anion seems promising.
Factors Affecting Scale Formation in Sea Water Environments – An Experimental Approach
Authors: Alahmad M. 
Published: December 2007

AbstractSea water is a complex aqueous environment with a large tendency for scale formation, which is usually ascribed to scaling from dissolved salts and suspended particles. Scale formation is causing many problems in thermal processes such as desalination and steam generation plants. In a typical desalination plant, ca. 40 % of the heat transfer area is provided to allow for scale formation problems, which is equivalent to a ca. 10 % increase of the whole capital cost of the plant. The main constituents forming scale in sea water environments, i.e., calcium carbonate, calcium sulfate and magnesium hydroxide, are extensively investigated in the present work. In order to obtain a better understanding of the scaling tendency of the seawater environment, an experimental unit was precisely designed and coupled with a data acquisition system for continuous monitoring of the investigated parameters. Significant factors affecting scale formation such as concentration of salts, flow velocity, water temperature and pH of the environments were studied at length using mild steel and stainless steel (smooth and rough). Hydrodynamic parameters such as Reynolds number and shear stress were used in the analysis of the collected data and revealed the role of shear stress in the effective removal of scale. The Kern‐Seaton scale model was used to calculate the fouling resistance in each case and the values obtained were compared with the experimental results. A modification of this model was also undertaken to provide better agreement with experimental findings.
Study of the Characteristics of Methanol Synthesis in a Recirculation Slurry Reactor – A Novel Three‐Phase Synthesis Reactor
Authors: Hu L. H. , Wang X. J. , Yu G. S. , Wang F. C. , Yu Z. H. 
Published: December 2007

AbstractA process feasibility analysis on the liquid phase methanol synthesis (LPMeOHTM) process was performed in a recirculation slurry reactor (RSR). In the three‐phase RSR system, a fine catalyst is slurried in the paraffin and this catalyst slurry is continuously recirculated through the nozzle from the slurry sector to the entrained sector by a pump. The syngas is fed concurrently with the downward flow of slurry to form the methanol product. A laboratory scale mini‐pilot plant version of a recirculation slurry reactor system was successfully designed and built to carry out process engineering research, and in addition, an identical cold model was built to measure the mass transfer coefficient in the recirculation slurry reactor. The effects of operating conditions, including temperature, pressure, gas flow rate and catalyst slurry recirculation flow rate on the productivity of methanol were studied. This experimental data helps the scale‐up and commercialization of the methanol synthesis process in recirculation slurry reactors.
Measuring Average Particle Size for Fluidized Bed Reactors by Employing Acoustic Emission Signals and Neural Networks
Authors: Chen X. M. , Chen D. Z. 
Published: December 2007

AbstractAverage particle size is one of the key parameters of fluidized bed reactors. A novel method to measure the average particle size in fluidized bed reactors by acoustic emission (AE) signal is proposed. The measurement of the average particle size by AE is superior to other methods since it is inherently safe to use and it is also a non‐invasive method. AE signals originating from different particle sizes were 8‐level decomposed by a Daubechies wavelet of order 3 after being denoised with a sym8 wavelet filter combined with the rigrsure threshold method. Principal component analysis (PCA) was applied to overcome the complex collinearity and reduce the number of input variables of the neural network. A feed‐forward back propagation neural network with two hidden layers was used to predict the average particle size according to the principal components. The results show that this soft‐measuring model is suitable for measuring the average particle size in the fluidized bed reactors by online AE. It achieved high accuracy when applied to a model‐scale fluidized bed.
Particle Shape and Purity in Membrane Based Crystallization
Authors: Weckesser D. , König A. 
Published: December 2007

AbstractWell‐controlled crystallization is the best method for preparing materials that are uniform in shape, size, structure and purity. The driving forces for crystallization are local gradients of supersaturation as the source and desupersaturation as the drain. Very high local supersaturation causes a high growth rate and represents a limiting factor for unstable modifications and product impurities. Hybrid membrane technology provides an interesting tool for controlling and limiting the maximum level of supersaturation due to defined mass transfer across the membrane. In this paper, the level of crystal growth rate in the system NaCl/KCl/water is varied by using different crystallization techniques. Vacuum evaporation crystallization (high growth rate) is compared to membrane based evaporation crystallization (low growth rate) and the results are interpreted in terms of product purity, particle shape and size. Membrane based crystallization in combination with effective solid/liquid separation as well as high performance analytics is suggested as a significant ultrapurification methodology.
Numerical Investigation of Hydrocarbon Enrichment of Process Gas Mixtures by Permeation through Polymeric Membranes
Authors: Kawachale N. , Kumar A. , Kirpalani D. M. 
Published: December 2007

AbstractIn membrane‐based gaseous separations, a consensus on the distribution of the components of the permeate stream in the immediate membrane vicinity has yet to be reached and the possibility of an underestimation of selective gas permeance due to lack of gas mixing on the permeate side exists. In this work, a numerical study of the permeation of ethylene and propylene in their binary mixtures with nitrogen through a composite poly(dimethylsiloxane) coated polysulfone membrane was performed. Continuity and momentum equations, along with gas compressibility and permeance properties for individual species of the gas mixture, were introduced into a comprehensive computational fluid dynamics (CFD) model. Simulation results showed that irrespective of the stage‐cut, gases with higher selectivity were well mixed in the vicinity of the membrane on the permeate side.
Co‐current and Countercurrent Configurations for a Membrane Dual Type Methanol Reactor
Authors: Rahimpour M. R. , Lotfinejad M. 
Published: December 2007

AbstractA dynamic model for a membrane dual‐type methanol reactor was developed in the presence of catalyst deactivation. This reactor is a shell and tube type where the first reactor is cooled with cooling water and the second one with feed synthesis gas. In this reactor system, the wall of the tubes in the gas‐cooled reactor is covered with a palladium‐silver membrane which is only permeable to hydrogen. Hydrogen can penetrate from the feed synthesis gas side into the reaction side due to the hydrogen partial pressure driving force. Hydrogen permeation through the membrane shifts the reaction towards the product side according to the thermodynamic equilibrium. Moreover, the performance of the reactor was investigated when the reaction gas side and feed gas side streams are continuously either co‐current or countercurrent. Comparison between co‐current and countercurrent mode in terms of temperature, activity, methanol production rate as well as permeation rate of hydrogen through the membrane shows that the reactor in co‐current configuration operates with lower conversion and also lower permeation rate of hydrogen but with longer catalyst life than does the reactor in countercurrent configuration.
Flue Gas Desulfurization by a Powder‐Particle Spouted Bed
Authors: Moeini M. , Hatamipour M. S. 
Published: December 2007

AbstractThe powder‐particle spouted bed process is one of the semi‐dry processes that have been developed for flue gas desulfurization. In this study, which is designed for SO2 removal by a powder‐particle spouted bed, the reaction term is included in one‐dimensional and streamtube models that were presented previously for spouted beds. Hydrated lime is used as the sorbent in this process. The predictions of the models are compared with some published experimental data and it is found that the developed models are valid. The results of two models are compared with each other and their various properties are evaluated. The effects of different operating conditions on SO2 removal efficiency are also investigated and preferred operating conditions are discussed.
The Effect of Oxygen Concentration on the Reaction of NOx with Soot Over BaAl2O4
Authors: Li Y. J. , Lin H. , Shangguan W. F. , Huang Z. 
Published: December 2007

AbstractThe effect of oxygen concentration on the catalytic reaction of NOx with soot over BaAl2O4 has been studied by Diffuse Reflectance Fourier Transform Infrared Spectroscopy (DRIFTS). The introduction of O2 into the NO flow can result in a reactant mixture of NO/NO2/O2. Increasing the O2 concentration from 2 % to 5 % in the NO‐containing flow promotes the formation of NO2 from the gas phase oxidation of NO. The reactant mixture with high O2/NO flow, allows for the formation of greater amounts of nitrate species than that with low O2/NO flow, which further promotes the reaction of soot with NOx and leads to a high conversion efficiency of NOx into N2 and N2O. In the absence of O2, N2O is not observed since the N2O produced at high temperatures has reacted with soot before it can be detected.
Temperature‐Programmed Oxidation of Soot in a Hybrid Catalysis‐Plasma System
Authors: Lin H. , Huang Z. , Shangguan W. F. 
Published: December 2007

AbstractNon‐thermal plasma (NTP) technology was applied to promote the temperature‐programmed oxidation (TPO) of soot over a perovskites type of La0.8K0.2MnO3 catalyst. The O radicals originating from the decomposition of O2, as well as NO dissociation if nitrogen oxide were involved, reduce the ignition temperatures of soot. In NO‐O2‐He, for example, the ignition temperature decreased to 240 °C from 290 °C as the voltage increased from 0 kV to 15 kV. The higher voltage also benefited the adsorption of NO molecules onto the catalyst surface (NOad). As a result, the maximum N2/NO ratio (conversion ratio of NO into N2) rose from 23 % to 53 %. Some of the NO molecules were dissociated into N and O radicals in plasma, and hence, the N2/NO ratio was further enhanced due to the combination of N atoms. In any case, the redox process between NOx and soot proved to be important in soot oxidation.