bluuebunny/crossref_metadata_2025_split huggingface dataset:
Patterns of strain in the macaque tibia during functional activity
Authors: Demes Brigitte , Qin Yi‐Xian , Stern Jack T. , Larson Susan G. , Rubin Clinton T. 
Published: November 2004

AbstractThe strain environment of the tibial midshaft of two female macaques was evaluated through in vivo bone strain experiments using three rosette gauges around the circumference of the bones. Strains were collected for a total of 123 walking and galloping steps as well as several climbing cycles. Principal strains and the angle of the maximum (tensile) principal strain with the long axis of the bone were calculated for each gauge site. In addition, the normal strain distribution throughout the cross section was determined from the longitudinal normal strains (strains in the direction of the long axis of the bone) at each of the three gauge sites, and at the corresponding cross‐sectional geometry of the bone. This strain distribution was compared with the cross‐sectional properties (area moments) of the midshaft. For both animals, the predominant loading regime was found to be bending about an oblique axis running from anterolateral to posteromedial. The anterior and part of the medial cortex are in tension; the posterior and part of the lateral cortex are in compression. The axis of bending does not coincide with the maximum principal axis of the cross section, which runs mediolaterally. The bones are not especially buttressed in the plane of bending, but offer the greatest strength anteroposteriorly. The cross‐sectional geometry therefore does not minimize strain or bone tissue. Peak tibial strains are slightly higher than the peak ulnar strains reported earlier for the same animals (Demes et al. [1998] Am J Phys Anthropol 106:87–100). Peak strains for both the tibia and the ulna are moderate in comparison to strains recorded during walking and galloping activities in nonprimate mammals. Am J Phys Anthropol 116:257–265, 2001. © 2001 Wiley‐Liss, Inc.
Field methodology for lateral cranial radiography of nonhuman primates
Authors: Schillaci Michael A. , Jones‐Engel Lisa , Heidrich John E. , Miller Gerald P. , Froehlich Jeffery W. 
Published: November 2004

AbstractThe historical lack of field‐based radiographic studies of nonhuman primates within the field of anthropology is likely due to the perceived difficulty of transporting and operating X‐ray equipment. Here we present a method for taking lateral cranial radiographs of nonhuman primates in the field that is simple to employ, and that produces exposed films suitable for collection of measurement data useful for growth and development studies, as well as for investigating bone and soft‐tissue pathology. Several different X‐ray units, film types, and portable power sources were used, all producing suitable images of similar quality, indicating that this methodology is likely not overly sensitive to these important parameters. Am J Phys Anthropol 116:278–284, 2001. © 2001 Wiley‐Liss, Inc.
An open source agenda for research linking text and image content features
Authors: Goodrum Abby A. , Rorvig Mark E. , Jeong Ki‐Tai , Suresh Chitturi 
Published: November 2004

AbstractThe use of primitive content features of images for classification and retrieval has matured over the past decade. However, human beings often prefer to locate images using words. This article proposes a number of methods to utilize image primitives to support term assignment for image classification. Further, the authors propose to release code for image analysis in a common tool set for other researchers to use. Of particular interest to the authors is the expansion of work by researchers in image indexing to include image content based feature extraction capabilities in their work.
Using clustering techniques to detect usage patterns in a Web‐based information system
Authors: Chen Hui‐Min , Cooper Michael D. 
Published: November 2004

AbstractDifferent users of a Web‐based information system will have different goals and different ways of performing their work. This article explores the possibility that we can automatically detect usage patterns without demographic information about the individuals. First, a set of 47 variables was defined that can be used to characterize a user session. The values of these variables were computed for approximately 257,000 sessions. Second, principal component analysis was employed to reduce the dimensions of the original data set. Third, a two‐stage, hybrid clustering method was proposed to categorize sessions into groups. Finally, an external criteria‐based test of cluster validity was performed to verify the validity of the resulting usage groups (clusters). The proposed methodology was demonstrated and tested for validity using two independent samples of user sessions drawn from the transaction logs of the University of California's MELVYL® on‐line library catalog system (www.melvyl.ucop.edu). The results indicate that there were six distinct categories of use in the MELVYL system: knowledgeable and sophisticated use, unsophisticated use, highly interactive use with good search performance, known‐item searching, help‐intensive searching, and relatively unsuccessful use. Their characteristics were interpreted and compared qualitatively. The analysis shows that each group had distinct patterns of use of the system, which justifies the methodology employed in this study.
Hydrazine‐induced post‐chemiluminescence phenomenon of permanganate–luminol reaction and its applications
Authors: Du Jianxiu , Lu Jiuru 
Published: November 2004

AbstractThe post‐chemiluminescence phenomenon arising from the permanganate–luminol reaction induced by hydrazine and isoniazid was investigated. When hydrazine or isoniazid was injected into the mixture after the end of the reaction of permanganate with alkaline luminol, a new chemiluminescence (CL) reaction was initiated and strong CL signal was detected. A possible CL mechanism is suggested, based upon the studies of the kinetic characteristics of the CL reaction, the UV‐visible spectra, the CL spectra and some other experiments. The present reactions allow the determination of 0.1–10.0 mg/L hydrazine and 0.02–1.0 mg/L isoniazid, with detection limits of 0.03 mg/L and 0.006 mg/L, respectively. The method was applied to the determination of isoniazid in pharmaceutical preparations. Copyright © 2004 John Wiley & Sons, Ltd.
Long-term results and risk factors influencing outcome of major bile duct injuries following cholecystectomy
Authors: Schmidt S C , Langrehr J M , Hintze R E , Neuhaus P 
Published: November 2004

Abstract

Background
Major bile duct injuries usually need operative repair and remain a challenge even for surgeons who specialize in hepatobiliary surgery. The purpose of this study was to evaluate management and short- and long-term outcomes of patients with major complications after cholecystectomy.

Methods
Data were analysed for 54 patients who underwent operation for major bile duct injuries after cholecystectomy between January 1990 and January 2002. Univariate and multivariate analyses were performed to identify risk factors for the development of biliary complications.

Results
Complete follow-up data were available for all 54 patients (median duration 61·9 (range 2·6–154·3) months). All underwent Roux-en-Y hepaticojejunostomy. Three patients (6 per cent) died from biliary tract complications during follow-up. Long-term biliary complications occurred in ten patients (19 per cent). Nine patients developed biliary stricture of whom five developed secondary biliary cirrhosis. A successful long-term result was achieved in 50 (93 per cent) of 54 patients, including those who required subsequent procedures. Biliary reconstruction in the presence of peritonitis (P = 0·002), combined vascular and bile duct injuries (P = 0·029), and injury at or above the level of the biliary bifurcation (P = 0·012) were significant independent predictors of poor outcome.

Conclusion
Successful repair of bile duct injuries after cholecystectomy can be achieved in specialized hepatobiliary units.
Emergency surgery for colonic cancer in a defined population
Authors: Jestin P , Nilsson J , Heurgren M , Påhlman L , Glimelius B , Gunnarsson U 
Published: November 2004

Abstract

Background
The aim of this study was to identify risk factors in emergency surgery for colonic cancer in a large population and to investigate the economic impact of such surgery.

Methods
Data from the colonic cancer registry (1997–2001) of the Uppsala/Örebro Regional Oncological Centre were analysed and classified by hospital category. Some 3259 patients were included; 806 had an emergency and 2453 an elective procedure. Data for calculating effects on health economy were derived from a national case-costing register.

Results
Patients who had emergency surgery had more advanced tumours and a lower survival rate than those who had an elective procedure (5-year survival rate 29·8 versus 52·4 per cent; P &lt; 0·001). There was a stage-specific difference in survival, with poorer survival both for patients with stage I and II tumours and for those with stage III tumours after emergency compared with elective surgery (P &lt; 0·001). Emergency surgery was associated with a longer hospital stay (mean 18·0 versus 10·0 days; P &lt; 0·001) and higher costs (relative cost 1·5 (95 per cent confidence interval 1·4 to 1·6)) compared with elective surgery. The duration of hospital stay was the strongest determinant of cost (r2 = 0·52, P &lt; 0·001).

Conclusion
Emergency surgery for colonic cancer is associated with a stage-specific increase in mortality rate.
Early prediction of organ failure by combined markers in patients with acute pancreatitis
Authors: Mentula P , Kylänpää M-L , Kemppainen E , Jansson S-E , Sarna S , Puolakkainen P , Haapiainen R , Repo H 
Published: November 2004

Abstract

Background
Several biological markers and clinical scoring systems have been used to predict the course of acute pancreatitis. Because organ failure is the most severe complication of the disease, prognostic markers and their combinations that would predict organ failure on hospital admission were sought.

Methods
Some 351 consecutive patients with acute pancreatitis were studied. Blood samples were taken within 12 h of admission. This case–control study included all 33 patients with organ failure and 99 matched controls without organ failure. Measurements included 19 prognostic markers and Acute Physiology And Chronic Health Evaluation (APACHE) II score.

Results
Plasma interleukin 10, serum glucose and serum calcium were identified as independent predictors of organ failure by logistic regression analysis. Calcium level correlated with clinical onset of organ failure. The combination of interleukin 10 (more than 50 pg/ml) or calcium (less than 1·65 mmol/l) was a significantly better predictor than any single marker or APACHE II score, with a sensitivity of 88 per cent, specificity 93 per cent and diagnostic odds ratio 94.

Conclusion
Organ failure in acute pancreatitis can be predicted with high accuracy at hospital admission using a combination of plasma interleukin 10 and serum calcium measurements.
Randomized clinical trial of the effect of intravenous fluid administration on hormonal and renal dysfunction in patients with obstructive jaundice undergoing endoscopic drainage
Authors: Padillo F J , Briceño J , Cruz A , Chicano M , Naranjo A , Vallejo J , Martín-Malo A , Pera-Madrazo C , Sitges-Serra A 
Published: November 2004

Abstract

Background
Renal dysfunction in patients with biliary obstruction is associated with extracellular water depletion. This study examined the effect of preoperative saline infusion before biliary drainage on hormonal and renal functional derangements in patients with obstructive jaundice.

Methods
In a randomized study, 49 patients with malignant obstructive jaundice were investigated at baseline, on the day of drainage, and at 24 h, 72 h and 7 days after internal endoscopic biliary drainage. Patients were randomized to receive (n = 22) or not to receive (n = 27) 3000 ml normal saline intravenously for 24 h before drainage. Variables analysed included extracellular water volume, creatinine clearance, and serum levels of aldosterone, renin, atrial natriuretic peptide (ANP), vasopressin and albumin.

Results
Preoperative saline infusion produced a rise in creatinine clearance, diuresis, ANP concentration and extracellular water volume but this did not translate into better recovery of renal function after operation. Drainage produced a fall in creatinine clearance in all patients, but hormonal and renal function had recovered by 2 days after restoration of bile flow, independently of preoperative hydration.

Conclusion
Fluid administration expands the extracellular water compartment before drainage but fails to improve renal function after drainage. Definitive improvement in endocrine and renal function requires the restoration of bile flow into the duodenum.
Synaptic structural abnormalities in the Ts65Dn mouse model of down syndrome
Authors: Belichenko Pavel V. , Masliah Eliezer , Kleschevnikov Alexander M. , Villar Angela J. , Epstein Charles J. , Salehi Ahmad , Mobley William C. 
Published: November 2004

AbstractThe Ts65Dn mouse is a genetic model for Down syndrome. Although this mouse shows abnormalities in cognitive function that implicate hippocampus as well as marked deficits in hippocampal long‐term potentiation, the structure of the hippocampus has been little studied. We characterized synaptic structure in Ts65Dn and control (2N) mice, studying the hippocampus (fascia dentata, CA1) as well as the motor and somatosensory cortex, entorhinal cortex, and medial septum. Confocal microscopy was used to examine immunostained presynaptic boutons and to detail the structure of dendrites after Lucifer yellow microinjection. Both presynaptic and postsynaptic elements were significantly enlarged in Ts65Dn in all regions examined. The changes were detected at the youngest age examined (postnatal day 21) and in adults. In studies detailing the changes in fascia dentata and motor cortex, the enlargement of spines affected the entire population, resulting in the presence of spines whose volume was greatly increased. Electron microscopy confirmed that boutons and spines were enlarged and demonstrated abnormalities in the internal membranes of both. In addition, spine density was decreased on the dendrites of dentate granule cells, and there was reorganization of inhibitory inputs, with a relative decrease in inputs to dendrite shafts and an increase in inputs to the necks of spines. Taken together, the findings document widespread abnormalities of synaptic structure that recapitulate important features seen in Down syndrome. They establish the Ts65Dn mouse as a model for abnormal synapse structure and function in Down syndrome and point to the importance of studies to elucidate the mechanisms responsible for synapse enlargement. J. Comp. Neurol. 480:281–298, 2004. © 2004 Wiley‐Liss, Inc.
A Stereoselective Carbocyclization of Bis(allenes) with Germylstannane Catalyzed by Palladium Complexes
Authors: Hong Young‐Taek , Yoon Seok‐Keun , Kang Suk‐Ku , Yu Chan‐Mo 
Published: November 2004

AbstractDiastereoselective germastannylation of bis(allenes) with germylstannanes, catalyzed by palladium complexes, for the construction of cis or trans five‐membered cyclic systems has been investigated. We observed that the relative stereochemical arrangements of the reaction products depends on the substituents in the reagents containing Ge−Sn σ‐bonds. When the reagent Ph3GeSnBu3 was employed in the Pd0‐catalyzed carbocyclization of bis(allenes), trans‐cyclized products and/or cis‐fused bicyclic dienes were produced. In contrast, cis cyclic compounds were obtained, again along with cis‐fused bicyclic dienes, from the reaction with Bu3GeSnBu3. NMR experiments to establish the stereochemical relationships and a mechanistic speculation for this transformation as a possible explanation for the different stereochemical outcomes are also described. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Total Synergistic Effect between Triflic Acid and Bismuth(III) or Antimony(III) Chlorides in Catalysis of the Methanesulfonylation of Arenes
Authors: Peyronneau Magali , Boisdon Marie‐Thérèse , Roques Nicolas , Mazières Stéphane , Le Roux Christophe 
Published: November 2004

AbstractA total synergistic effect between bismuth(III) or antimony(III) chlorides and triflic acid has been observed in the Friedel−Crafts methanesulfonylation of arenes and has resulted in the development of the first efficient catalytic systems usable for the methanesulfonylation of both activated and deactivated arenes. A proposed mechanism to explain the observed effects is also discussed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Stereochemical Assignment of Diastereomeric Imidazolidinone‐Ring‐Containing Bicyclic Sugar‐Peptide Adducts: NMR Spectroscopy and Molecular Calculations
Authors: Roščić Maja , Eklund Robert , Nordmark Eva‐Lisa , Horvat Štefica , Widmalm Göran 
Published: November 2004

AbstractA combination of NMR spectroscopy and molecular simulations is used to determine trans/cis configurational features of two diastereomeric bicyclic imidazolidinone compounds obtained by intramolecular cyclization of the monosaccharide ester of leucine‐enkephalin related to D‐glucose. The stereochemical assignment of the five‐membered imidazolidinone ring system was performed by consideration of long‐range proton‐proton coupling observed between protons at C2 and C4 in the COSY spectrum of the major isomer only. A long‐range 4JH,H coupling across the nitrogen atoms is larger in the trans isomer than in the cis. In addition, comparison of these results with the NMR spectroscopic data obtained for the major isomer of D‐galactose‐related imidazolidinone and those previously obtained by X‐ray methods for the corresponding minor isomer, show that the substituents attached to the imidazolidinone ring moiety in the studied compounds preferentially adopt the trans (2R,4S) orientation. The experimental results were complemented by density functional theory calculations of NMR‐observable parameters, such as 1H and 13C chemical shifts and 4JH,H coupling constants, performed on simplified imidazolidinone ring systems. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Intramolecular Ritter Reactions of 2‐(2‐Cyanoethyl)tetrahydrocyclopenta[b]indole and ‐carbazole Derivatives
Authors: Maertens Faye , Van den Bogaert An  , Compernolle Frans , Hoornaert Georges J. 
Published: November 2004

AbstractIntramolecular Ritter reactions of 2‐(2‐cyanoethyl)tetrahydrocyclopenta[b]indole and ‐carbazole derivatives, prepared by a sequence of two different α‐substitutions and Grignard reactions of the indole‐based ketones 4‐methyl‐1,4‐dihydrocyclopenta[b]indol‐3(2H)‐one and 9‐methyl‐2,3,4,9‐tetrahydro‐1H‐carbazol‐1‐one, were used as key steps in the construction of various tetracyclic lactam compounds. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Effective Activation of the Chiral Salen/Ti(OiPr)4 Catalyst with Achiral Phenolic N‐Oxides as Additives in the Enantioselective Cyanosilylation of Ketones
Authors: He Bin , Chen Fu‐Xue , Li Yan , Feng Xiaoming , Zhang Guolin 
Published: November 2004

AbstractThe activation of chiral titanium(IV) complexes with phenolic N‐oxides additives has been found to provide an alternative strategy for the asymmetric cyanosilylation of ketones. By using 10 mol % of chiral salen−titanium(IV) complex in combination with 1 mol % achiral phenolic N‐oxide as an additive, aromatic, aliphatic and heterocyclic ketones have been converted into the corresponding cyanohydrin trimethylsilyl ethers in 58−96% yields with 56−82% ee. Several factors concerning the reactivity and enantioselectivity have been discussed. A catalytic cycle based on experimental phenomena and studies has been proposed to explain the origin of this activation and the asymmetric induction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Towards a Selective Functionalization of Amino‐Terminated Dendrimers
Authors: Vögtle Fritz , Fakhrnabavi Hassan , Lukin Oleg , Müller Sonja , Friedhofen Jörg , Schalley Christoph A. 
Published: November 2004

AbstractSelective functionalization of the periphery of commercial polypropyleneamine (POPAM) and polyamidoamine (PAMAM) dendrimers has been investigated in preparative scale. The first generation (G1) POPAM dendrimer was for the first time selectively N,N‐bis(sulfonylated) with tosyl chloride and the corresponding mono‐, di‐, tri‐, and tetra‐N‐tosylsulfonamides were isolated and fully characterized. Unexpectedly, similar persulfonylation of G2 POPAM results in splitting of a central C−N bond and only fully and partially sulfonylated halves of the initial dendrimer could be isolated. Higher generations of POPAM are also split during the persulfonylation yielding complex mixtures of persulfonylated dendritic fragments which could hardly be identified. A plausible mechanism of the POPAM decomposition on the basis of the reaction product analysis is proposed. N‐Sulfonylation of a peripheral octasulfonamide of G2 POPAM with tosyl chloride also leads to the destruction of the dendrimer, while its N‐alkylation with benzyl bromide proved to be not selective yielding a completely alkylated derivative. Unlike POPAM dendrimers, PAMAM dendrimers were shown to be more stable during their sulfonylation and no decomposition of the dendritic backbone was detected. In contrast to the POPAM dendrimers, PAMAM dendrimers were shown to be rather inert with respect to the formation of N‐tosylsulfonamides since they could only be N‐monosulfonylated at all peripheral amino groups. The combination of MALDI‐TOF and ESI‐FT‐ICR tandem mass spectrometry has been shown to be an effective method for structure assignment and purity check of selectively or fully persulfonylated dendritic oligoamines. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Stationary Fuel Cells at Work – An Interim Report
Authors: Edel M. , Frey H. , Kessler A. , Münch W. 
Published: November 2004

AbstractDifferent fuel cell systems, in various numbers, have been installed and run at customers' sites using natural gas. Operational results from these field tests are presented, which demonstrate that several fuel cell systems can be used successfully to generate heat and electricity. Improved reliability and cutting costs are the most urgent challenges for commercialisation.
Mathematical Model of a Residential Fuel Cell Power Plant and its Application to Start‐up Optimisation
Authors: Jahn H.‐J. , Schroer W. 
Published: November 2004

AbstractFuel cell power plants are complex, non‐linear systems. Their control is not yet sufficiently resolved. According to recent publications [1] and based on our own experience, with a demonstration plant, problems exist especially at plant start‐up and under dynamic operating conditions.In an ongoing project, optimal control concepts are developed with the main focus on plant start‐up.The first part of this paper describes the demonstration plant and depicts the present problems. The second part describes the plant model, which was derived based on physical and chemical laws. It is the basis for control system design and optimisation. The third part covers the start‐up process and its optimisation.Our project partners are the Department for Energy Conversion and Storage of the University of Ulm and the Centre for Solar Energy and Hydrogen Research Baden‐Württemberg (ZSW).