bluuebunny/crossref_metadata_2025 huggingface dataset:
Improvement in alkoxide anionic initiation technique by using a colorimetric titration
Authors: Compos Delphine , Delaite Christelle , Hurtrez Guy , Dumas Philippe
Published: August 2005

We developed a colorimetric method to follow and to control the complete transformation of an alcohol into an alkoxide. It was first tested on a small molecule and then extended to a macroinitiator. It allows us to obtain a final product without residual prepolymer and without side initiation due to an excess of carbanion. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1339–1343, 2005
Specialization in pyramidal cell structure in the sensory‐motor cortex of the Chacma baboon (Papio ursinus) with comparative notes on macaque and vervet monkeys
Authors: Elston Guy N. , Benavides‐Piccione Ruth , Elston Alejandra , Manger Paul R. , Defelipe Javier
Published: August 2005

The systematic study of pyramidal cell structure has revealed new insights into specialization of the phenotype in the primate cerebral cortex. Regional specialization in the neuronal phenotype may influence patterns of connectivity and the computational abilities of the circuits they compose. The comparative study of pyramidal cells in homologous cortical areas is beginning to yield data on the evolution and development of such specialized circuitry in the primate cerebral cortex. Recently, we have focused our efforts on sensory‐motor cortex. Based on our intracellular injection methodology, we have demonstrated a progressive increase in the size of, the branching structure in, and the spine density of the basal dendritic trees of pyramidal cells through somatosensory areas 3b, 1, 2, 5, and 7 in the macaque and vervet monkeys. In addition, we have shown that pyramidal cells in premotor area 6 are larger, more branched, and more spinous than those in the primary motor cortex (MI or area 4) in the macaque monkey, vervet monkey, and baboon. Here we expand the basis for comparison by studying the basal dendritic trees of layer III pyramidal cells in these same sensory‐motor areas in the chacma baboon. The baboon was selected because it has a larger cerebral cortex than either the macaque or vervet monkeys; motor cortex has expanded disproportionately in these three species; and motor cortex in the baboon reportedly has differentiated to include a new cortical area not present in either the macaque or vervet monkeys. We found, as in monkeys, a progressive increase in the morphological complexity of pyramidal cells through areas 3b, 5, and 7, as well as from area 4 to area 6, suggesting that areal specialization in microcircuitry was likely to be present in a common ancestor of primates. In addition, we found subtle differences in the extent of the interareal differences in pyramidal cell structure between homologous cortical areas in the three species. © 2005 Wiley‐Liss, Inc.
Determination of enantiomeric composition by negative‐ion electrospray ionization–mass spectrometry using deprotonated N‐(3,5‐dinitrobenzoyl)amino acids as chiral selectors
Authors: Brewer Bobby N. , Zu Chengli , Koscho Michael E.
Published: August 2005

The ability to use mixtures of deprotonated N‐(3,5‐dinitrobenzoyl)amino acids as chiral selectors for the determination of enantiomeric composition by electrospray ionization–mass spectrometry is demonstrated. For each experiment, two N‐(3,5‐dinitrobenzoyl)amino acids were chosen such that each would have opposite selectivity for the enantiomers of the analyte. Electrospray ionization–mass spectrometry, monitored in the negative ion mode, of solutions containing the two N‐(3,5‐dinitrobenzoyl)amino acids, sodium hydroxide, and the analyte, in a one‐to‐one mixture of methanol and water, afford peaks in the mass spectrum that correspond to the deprotonated 1:1 analyte–selector complexes. The ratio of the intensities of the complexes in the mass spectrum can be related to the enantiomeric composition of the analyte. Additionally, the sense and extent of chiral recognition is consistent with chromatographic observations, using chiral stationary phases derived from N‐(3,5‐dinitrobenzoyl)amino acids. Each analysis of enantiomeric composition requires less than 10 s to complete, indicating that this method has great potential for the development of fast‐/high‐throughput chiral analyses. © 2005 Wiley‐Liss, Inc. Chirality 17:456–463, 2005.
Electrophoresis‐assisted open‐tubular liquid chromatography/mass spectrometry for the analysis of lipooligosaccharide expressed by Campylobacter jejuni
Authors: Li Jianjun , Koga Michiaki , Brochu Denis , Yuki Nobuhiro , Chan Kenneth , Gilbert Michel
Published: August 2005

Lipooligosaccharide (LOS) is the major component of the external membrane of Campylobacter jejuni. LOS contains a hydrophobic moiety, lipid A, and a hydrophilic moiety, oligosaccharide. Due to the unique mimicry of human ganglioside structures and potential involvement in the induction of the autoimmune polyneuropathies, Guillain–Barré and Miller Fisher syndromes, the structural characterization of C. jejuni LOS has received much attention. We have been using capillary zone electrophoresis–mass spectrometry to analyze O‐deacylated LOS from C. jejuni. In an attempt to optimize the separation conditions, the effect of methanol on the separation of LOS was investigated. It was found that methanol resulted in stronger adsorption of LOS onto the wall of fused‐silica capillary. In this paper, we applied this adsorption to perform electrophoresis‐assisted open‐tubular liquid chromatography electrospray mass spectrometry for the analysis of O‐deacylated LOS mixtures from C. jejuni. The analytical potential of the proposed strategy for the analysis of O‐deacylated LOS glycoforms from five bacterial colonies is demonstrated. Online tandem mass spectrometry is shown to provide a powerful tool for characterization of variations in the hexosamine backbone, phosphorylation of the lipid A, and sialic acid sequence information.
Effect of background electrolyte on the estimation of protein hydrodynamic radius and net charge through capillary zone electrophoresis
Authors: Piaggio Maria V. , Peirotti Marta B. , Deiber Julio A.
Published: August 2005

Two physicochemical models are proposed for the estimation of both hydrodynamic radius and net charge of a protein when the capillary zone electrophoretic mobility at a given protocol, the set of pK of charged amino acids, and basic data from Protein Data Bank are available. These models also provide a rationale to interpret appropriately the effects of solvent properties on protein hydrodynamic radius and net charge. To illustrate the numerical predictions of these models, experimental data of electrophoretic mobility available in the literature for well‐defined protocols are used. Five proteins are considered: lysozyme, staphylococcal nuclease, human carbonic anhydrase, bovine carbonic anhydrase, and human serum albumin. Numerical predictions of protein net charges through these models compare well with the results reported in the literature, including those found asymptotically through protein charge ladder techniques. Model calculations indicate that the hydrodynamic radius is sensitive to changes of the protein net charge and hence it cannot be assumed constant in general. Also, several limitations associated with models for estimating protein net charge and hydrodynamic radius from protein structure, amino acid sequence, and experimental electrophoretic mobility are provided and discussed. These conclusions also show clear requirements for further research.
Software framework for distributed experimental–computational simulation of structural systems
Authors: Takahashi Yoshikazu , Fenves Gregory L.
Published: August 2005

Supported by the recent advancement of experimental test methods, numerical simulation, and high‐speed communication networks, it is possible to distribute geographically the testing of structural systems using hybrid experimental–computational simulation. One of the barriers for this advanced testing is the lack of flexible software for hybrid simulation using heterogeneous experimental equipment. To address this need, an object‐oriented software framework is designed, developed, implemented, and demonstrated for distributed experimental–computational simulation of structural systems. The software computes the imposed displacements for a range of test methods and co‐ordinates the control of local and distributed configurations of experimental equipment. The object‐oriented design of the software promotes the sharing of modules for experimental equipment, test set‐ups, simulation models, and test methods. The communication model for distributed hybrid testing is similar to that used for parallel computing to solve structural simulation problems. As a demonstration, a distributed pseudodynamic test was conducted using a client–server approach, in which the server program controlled the test equipment in Japan and the client program performed the computational simulation in the United States. The distributed hybrid simulation showed that the software framework is flexible and reliable. Copyright © 2005 John Wiley & Sons, Ltd.
Endoluminal hydrogel films made of alginate and polyethylene glycol: Physical characteristics and drug‐eluting properties
Authors: Livnat Maya , Beyar Rafael , Seliktar Dror
Published: August 2005

Drug‐eluting stents signify a major achievement in reducing the incidence of coronary restenosis after percutaneous transluminal coronary angioplasty. However, where drug‐eluting stents have been unsuccessful, endoluminal gel‐paving strategies offer renewed optimism, mainly in a variety of vascular procedures requiring catheter‐based sustained, localized delivery of therapeutic drugs, and biological factors. Despite promising results in animals, endoluminal paving has met with very limited clinical success because of the technical difficulties and stringent safety demands. The current study presents an alternative to gel paving using 40‐μm‐thick biodegradable polymeric films for deployment onto the artery wall during balloon angioplasty and stenting. The films are made from a durable yet compliant network of alginate and polyethylene glycol (PEG), and are securely held affixed to the vessel wall by the expanded stent struts. The alginate‐based films are characterized by measuring their strength, elasticity, degree of swelling, degradability in water and saline, and drug release properties. The combination of alginate and PEG afforded the films sufficient strength and compliance for endoluminal deployment using an in vitro organ culture system. In characterizing the film degradability, it was discovered that the ionic concentration of the buffered saline was the main determinant in regulating the degradation kinetics and the release kinetics of the drug molecule Paclitaxel. These results suggest that the use of alginate‐based, PEG‐containing polymeric films for endoluminal coverage offers an alternative solution to conventional drug‐eluting stents, with the added advantage of uniform endoluminal coverage of the treated segment and homogeneous endoluminal application of the active substance. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2005
Assessing the impact of cancer: development of a new instrument for long‐term survivors
Authors: Zebrack Brad J. , Ganz Patricia A. , Bernaards Coen A. , Petersen Laura , Abraham Laura
Published: August 2005

Objective: To develop and evaluate a new instrument that measures aspects of long‐term survivorship not measured by existing tools.

Methods: In qualitative interviews, 47 long‐term cancer survivors (LTS) detailed ways that cancer has impacted their lives. Content analysis resulted in the creation of 325 candidate items for inclusion in a new Impact of Cancer (IOC) instrument. Following expert review, item reduction and pilot testing, 81 items were administered with other established health status and quality of life (QOL) instruments to 193 LTS of breast, prostate, colorectal cancers and lymphoma. Internal consistency reliability and validity of newly‐derived scales was assessed.

Results: Factor analysis of items using a priori QOL domains resulted in the derivation of ten new and specific subscales: Health Awareness, Body Changes, Health Worries, Positive and Negative Self‐Evaluation, Positive and Negative Life Outlook, Social Life Interferences, Relationships, and Meaning of Cancer. Internal consistency measurements for these subscales ranged from 0.67 to 0.89. Expected associations within and among the IOC subscales and standardized measures of health status and QOL were observed, as were some unexpected findings.

Conclusions: Psychometric analysis indicated that this initial version of the Impact of Cancer instrument measures distinct and relevant constructs for LTS. Future work is necessary to confirm the factor structure, responsiveness and further validation of the instrument. Copyright © 2005 John Wiley & Sons, Ltd.
Heterotic strings on homogeneous spaces
Authors: Israël D. , Kounnas C. , Orlando D. , Petropoulos P.M.
Published: August 2005

We construct heterotic string backgrounds corresponding to families of homogeneous spaces as exact conformal field theories. They contain left cosets of compact groups by their maximal tori supported by NS‐NS 2‐forms and gauge field fluxes. We give the general formalism and modular‐invariant partition functions, then we consider some examples such as SU (2)/U (1) ~
S2 (already described in a previous paper) and the SU (3)/U(1)2 flag space. As an application we construct new supersymmetric string vacua with magnetic fluxes and a linear dilaton.
Carbon at Si(111)‐twins: TEM analysis supported by molecular dynamics structure relaxations
Authors: Scheerschmidt Kurt , Werner Martina
Published: August 2005

Carbon supersaturation and high density of twin lamellae influence the physical properties of multi‐crystalline silicon and restrict its applicability as a material in photovoltaics. To understand, e.g., the resulting structural modifications and the stress relief, the carbon incorporation in silicon has to be investigated by total energy minimizations using molecular dynamics simulations either at ab‐initio level or applying classical methods with empirical potentials. The relaxed structure models support the interpretation of transmission electron micrographs by contrast simulations and thus the analysis of carbon incorporation at twins or elsewhere in silicon. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
PTIS investigation of hydrogenated CVD diamond films
Authors: Hikavyy A. , Clauws P. , Deferme W. , Bogdan G. , Haenen K. , Nesladek M.
Published: August 2005

Photo‐thermal ionization spectroscopy has been applied for investigation of hydrogenated diamond. All investigated films have shown presence of B after hydrogenation though no PTIS could be measured when they were oxidized. The presence of shallow levels with energy around 100 meV has been found in all hydrogenated samples at temperatures lower than 120–77 K depending on the sample. The photocurrent spectrum due to these shallow levels consists of features similar to two‐phonon absorption in diamond. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Exploring protein energy landscapes with hierarchical clustering
Authors: Gront Dominik , Hansmann Ulrich H. E. , Kolinski Andrzej
Published: August 2005

In this work we present a new method for investigating local energy minima on a protein energy landscape. The Cα(CA), Cβ(B), and the center of mass of the side chain (CABS) method was employed for generating protein models, but any other method could be used instead. Cα traces from an ensemble of models are hierarchical clustered with the hierarchical clustering of protein models (HCPM) method. The efficiency of this method for sampling and analyzing energy landscapes is shown. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Automated mechanism generation: From symbolic calculation to complex chemistry
Authors: Ratkiewicz Artur , Truong Thanh N.
Published: August 2005

Different aspects of the symbolic algebra computations for generating elementary reactions of complex systems are reviewed. Such calculations are the heart of each automated mechanism generator system and are employed extensively in different stages of mechanism generation. The range of symbolic calculation topics and basic ideas of these implementations, together with some specific examples, are given. Particular attention is devoted to the transition between the symbolic calculation and the real complex chemistry. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Autonomic influences on colorectal motility and pelvic surgery
Authors: Varma J. S.
Published: August 2005

The nervous control of the motility of the human distal bowel was investigated by two physiological studies of electrical stimulation of sacral parasympathetic outflow in patients with high spinal injuries and in patients with intractable constipation following pelvic surgery. Identical and reproducible motility responses of the left colon, rectum, and anal sphincters were obtained by sequential electrical stimulation of anterior sacral roots S2, S3, and S4 in patients with spinal injury. S2 stimulation provoked isolated low‐pressure colorectal contractions. S3 stimulation initiated frequency‐dependent high‐pressure colorectal motor activity which appeared peristaltic and was enhanced with repetitive stimuli. S4 stimulation increased colonic and rectal tone. Quantitative responses were maximal at the splenic flexure and rectum. Pelvic floor activity was stimulated in increasing magnitude from S2 to S4. These results of distal bowel motility were achieved by an implanted Brindley stimulator. A newer generation of externally active stimulators are envisaged for the control of lower bowel in fecal incontinence.

Women with intractable constipation following hysterectomy had significantly increased rectal volume and compliance together with deficits of rectal sensory function. Following stimulation with Prostigmin (neostigmin) a colorectal motility gradient was paradoxically reversed in the patients following hysterectomy, thus constituting a functional obstruction. Denervation supersensitivity was demonstrable in 2 patients tested with carbachol provocation. These findings suggest dysfunction in the autonomic innervation of the hindgut in some patients following hysterectomy.
Fecal incontinence: Indications for repairing the anal sphincter
Authors: Penninckx F.
Published: August 2005

Incontinent patients should be comprehensively investigated by objective tests, especially manometry, continence tests, and electromyography. Manometry can be used to predict the functional outcome and to calibrate the sphincter repair. Pure anatomical defects of the anal and pelvic musculature deserve surgical correction with or without overlapping the muscle ends. If the repair is delayed it should be done after a 3 month interval. A protective colostomy has to be performed in complex cases and in cases with septic complications. Before closing the colostomy, the ano‐rectal function should be assessed. Acceptable continence can be restored in the majority of the patients, the outcome depending on the extent of local defects and the severity of concomitant pelvic floor neuropathy. Skeletal muscle transposition remains an esoteric approach to be used only in selected patients; the implantation of a neuromuscular stimulator seems to be warranted. In the presence of important functional deficits, sphincter repair may create a situation where additional conservative measures become more effective. A post‐anal repair may be considered 3–12 months after rectopexy or sphincter repair. Incontinence based on pure functional defects is initially treated conservatively. A post‐anal repair may improve the situation in two thirds of the patients but fails to help those who need it most. Failure seems to be related to a continuing neuropathic process. A peri‐anal prosthetic band implant may be a valuable alternative in such patients. A sigmoidostomy is a measure of last resort. The prevention of fecal incontinence is most important and concerns surgeons, obstetricians, and physicians.
Anismus: The cause of constipation? Results of investigation and treatment
Authors: Duthie G. S. , Bartolo D. C. C.
Published: August 2005

Anismus, or failure of the somatic sphincter apparatus to relax at defecation, has been implicated as a major contributor to the problem of obstructed defecation. Current diagnostic methods depend on laboratory measurements of attempted defecation and the most complex, dynamic proctography has been the mainstay of diagnosis. Using a new computerized ambulatory method of recording sphincter function in these patients at home, we report an 80% reduction in our diagnostic rate suggesting that conventional tests fail to accurately diagnose this condition, probably because they poorly represent the natural physiology of defecation. Treatment of this distressing condition is more complex and a variety of surgical and pharmacological measures have failed. Biofeedback retraining of anorectal function of these patients has been very successful and represents the management of choice.
The results of pouch surgery after ileo‐anal anastomosis for inflammatory bowel disease: The manometric assessment of pouch continence and its reservoir function
Authors: Pescatori Mario
Published: August 2005

Anal sphincter function after restorative proctocolectomy has mainly been investigated by anal manometry. A significant decrease of basal pressure up to 45%, has been recorded postoperatively, possibly due to sphincter stretch during endoanal mucosectomy. Both abdominal mucosectomy and anastomosis at the level of the anorectal ring have been reported to prevent anal sphincter damage and lead to better continence. The striated sphincter is not significantly affected by the surgical procedure. Pouchanal inhibitory reflex is partly maintained in the presence of a rectal cuff which leaves the ganglionic plexus unaltered; a satisfactory continence is also retained in the absence of the reflex when the rectum is totally excised.

Pouch capacity, compliance and motility have been investigated by endoluminal balloon and probes. Pouch emptying has been studied by a “porridge” test, by a semi‐solid medium labelled with technetium‐99, and by other methods. A more effective storage function is achieved by large capacity reservoirs which lower the bowel frequency. The motor response to pouch distension, to a meal, and to pharmacological stimuli is usually counteracted by sphincter contraction. Ileal hypermotility may lead to fecal leakage mainly in the presence of weak sphincters. Poor pouch emptying may be related to an anal stricture.
Crush injury and crush syndrome
Authors: Michaelson Moshe
Published: August 2005

Crush injury is caused by continuous prolonged pressure on the limbs. It is found in patients extricated after being trapped for at least 4 hours. The main injury is to the muscles of the limbs. Treatment should be conservative and fasciotomy should be avoided. If fasciotomy is performed, it should be followed by radical debridement of the injured muscle in an attempt to avoid infection of the injured limb. Infection endangers the patient's life and is the main cause of morbidity and mortality today. The outcome of conservative local treatment of crush injury is much superior to that of operative treatment. The pathophysiology of crush injury is not fully understood and no good animal model is known. Crush syndrome, which is the general manifestation of crush injury, is better understood. If not prevented, it will lead to acute renal failure. A method for preventing acute renal failure is discussed and a protocol is described. There is no doubt that prevention of acute renal failure is the goal in the treatment of crush syndrome and can be achieved.
Triage: In austere environments and echeloned medical systems
Authors: Llewellyn Craig H.
Published: August 2005

Although triage as a medical sorting process was originally developed and applied to echeloned military field medical systems dealing with mass casualties, the term has now permeated most aspects of medical practice. This essay attempts to refocus on triage in military and disaster settings, emphasizing the relationship of the echeloned system organization to the triage process, and the various non‐medical factors which may influence triage decisions and priorities. Due to the lack of any analogous civilian experience, it is essential that all health personnel who may be involved in an echeloned care system gain and maintain proficiency by frequent involvement in appropriate training exercises, the characteristics of which are described.
The red cross classification of war wounds: The E.X.C.F.V.M. scoring system
Authors: Coupland Robin M.
Published: August 2005

The Red Cross classification of war wounds is based upon features of the wound, not upon weaponry. It is proposed as a new means of understanding, communicating, and gathering information about war wounds and their management. The wound score is based on the skin wounds and the presence of a cavity, fracture, vital injury, or metallic bodies in the wound. All wounds so scored can be graded according to severity and typed according to structures injured; consequently, wounds are identified by their clinical significance. A study of 247 wounds shows the feasibility of scoring wounds in the field and yields surgically relevant information about bullet and fragment wounds. The applications of the classification are to wound assessment, establishing a scientific basis to war surgery, surgical audit, and collecting wound data from the field.
Prevention of deep vein thrombosis in patients with hip fractures: Low molecular weight heparin versus dextran
Authors: Oertli D. , Hess P. , Dūrig M. , Laffer U. , Fridrich R. , Jaeger K. , Kaufmann R. , Harder F.
Published: August 2005

A randomized open trial was undertaken to compare the antithrombotic efficacy of a low molecular weight heparin (LMWH; Sandoparin®) with that of dextran 70 in patients undergoing surgery for hip fracture. One hundred thirteen patients received LMWH once daily subcutaneously at a fixed dosage while 103 patients received intravenous dextran 70. Postoperative deep vein thrombosis (DVT) was assessed by a diagnostic algorithm using the125Iodine fibrinogen uptake test as screening and Duplex ultrasonography and/or ascending venography as confirming techniques for suspected DVT. The frequency of DVT was significantly lower in the LMWH group than in the dextran group (15.5 versus 32.6%,p<0.005). Proximal DVT was rare in both groups (LMWH: 2%, Dextran: 1%). Only one case of fatal fat pulmonary embolism was observed during the 10 day prophylaxis period in a patient receiving Dextran. Three cases of pulmonary embolism occurred later; one fatal event in the dextran group on day 14, and two cases in the LMWH group (one fatal and one non‐fatal event) on day 14 and 17, respectively. There was no major bleeding complication in either group. We conclude that the LMWH we used is safe, was well tolerated, and has a significantly better thromboprophylactic effect than dextran 70.
Patterns of internal echoes in lymph nodes in the diagnosis of lung cancer metastasis
Authors: Lee Noritoshi , Inoue Kiyotoshi , Yamamoto Ryoji , Kinoshita Hiroaki
Published: August 2005

In 1989–90, all 37 lung cancer patients scheduled for surgery underwent transesophageal endoscopic ultrasonography (EUS) for pre‐operative detection of hilar and mediastinal lymph node metastases. An electronic ultrasonic fiberscope with a linear array (EPB‐503‐FS, Machida‐Toshiba) was used. Of 380 nodes surgically removed and that could have been detected by EUS, the detection rates for histologically metastatic and non‐metastatic nodes were 65% (33 of 51) and 44% (144 of 329), respectively (p<0.01). Metastatic nodes were detected readily in every lymph node site, especially subaortic and subcarinal. Non‐metastatic nodes were detected at low rates, especially in the superior mediastinum, paratracheal, and tracheobronchial locations. For greater long or short axes of the detected nodes, or for rounder nodes, the metastasis rate was higher. Detected nodes were classified into six types by their internal echo patterns; three were rarely metastatic (called “negative”) and the other three were often metastatic (called “positive”). Of the “negative” nodes histologically proved to be metastatic, metastasis was often diffuse. The “positive” nodes found to be metastatic tended to have one of two patterns of internal echoes when invasion was diffuse and a third pattern when it was localized. In an examination of the diagnostic usefulness of EUS, we made more correct diagnoses from the internal echo pattern than by reference to either the long or short axis alone. The short axes, node shape, and internal echoes were examined by Hayashi's second method of quantification. The sensitivity, specificity, and accuracy of the diagnoses were 85%, 84%, and 84%, respectively, superior to those by computed tomography done of the same patients.
24‐Hour intragastric pH measurement in the assessment of duodenogastric reflux
Authors: Brown T. H. , Holbrook I. , King R. F. G. , Ibrahim K.
Published: August 2005

In this study we compared the results of measurement of duodenogastric reflux using 24‐hour intragastric pH monitoring and nasogastric aspiration with analysis of bile acid and alpha amylase concentrations. Eight patients were studied at least 5 months after biliary and/or gastric surgery. The correlation coefficient of pH and bile acid concentration was 0.36 (p<0.001) and of pH and amylase concentration was 0.48 (p<0.001). If a pH > 4.0 was taken to indicate duodenogastric reflux this had a sensitivity of 84% compared with either high bile acid or amylase concentration. Bile acid concentration has been the “standard” method of measuring duodenogastric reflux. pH monitoring is relatively simple to perform, causes little patient distress, and can measure episodes of duodenogastric reflux over a continuous 24‐hour period.
Surgical problems in octogenarians: Epidemiological analysis of 1,083 consecutive admissions
Authors: Reiss R. , Deutsch A. , Nudelman I.
Published: August 2005

Patients older than 80 years of age are the most rapidly increasing group among surgical admissions and patients visiting emergency rooms. Epidemiological data of this group are of enormous medical and economic relevance. The principle aim of this study was to determine factors predictive of operative mortality in octagenarians, their clinical profiles, and length of stay compared to younger patients in similar diagnostic categories. A computer‐based registry of geriatric surgery was used to record and analyze all relevant clinical and epidemiological data. The rate of admissions in octogenarians increased during the 18‐year period (1973–1989) from 0.7% to 7.5% of all admissions. The number of patients undergoing surgery was 700. Three hundred and seventy‐one of the procedures were elective and 329 were emergencies. Operations in octagenarians as a percentage of all operative procedures increased during the period considered from 1.1% to 5.1%. The operative mortality in this series was 10.5% prior to 1984 and decreased to 6% during the last 5 years. The average hospital stay of octagenarians was 9.8 days as opposed to 4.9 days in patients <70 years of age. The prognostic classification described by the authors proved very helpful in predicting mortality.
Pre‐Operative radiotherapy as adjuvant treatment in rectal cancer
Authors: Izar F. , Fourtanier G. , Pradere B. , Chiotasso P. , Bloom E. , Fontes‐Dislaire I. , Bugat R. , Daly N.
Published: August 2005

From January, 1975 to December, 1987, 241 patients with rectal cancer underwent pre‐operative irradiation and surgical resection. The radiation was delivered with 25 MeV photons, 5 days per week by 2.4 grays fractions up to a total dose of 36 grays. Surgery was curative in 195 patients; 57% had abdomino‐perinal resection. Irradiation had to be discontinued in 3 patients and 4 patients subsequently developed severe acute ileitis. Postoperative mortality rate was 2.9%. The most frequent postoperative complications were delayed healing of abdominal wounds (18%) and perineal wounds (14%). Severe late complications occurred in 27 (13%) patients. The incidence of intestinal obstruction was 5%. Follow‐up survivors ranged from 18 months to 13 years. Local failure occurred in 24 (12%) of the 195 patients. Local failure rates were 10% for Dukes' A tumors, 11.6% for Dukes' B, and 22.7% for Dukes' C tumors. Five and 10 years actuarial survival rates after curative surgery were 70% and 52%. The Dukes' classification was the only factor that influenced survival.
Percutaneous drainage of pancreatic pseudocysts: A prospective study
Authors: D'Egidio Angelo , Schein Moshe
Published: August 2005

We classify pancreatic pseudocysts in 3 types: post‐necrotic type I, related to acute pancreatitis; post‐necrotic type II, related to an acute attack superimposed on chronic pancreatitis; and retention type III, due to chronic pancreatitis with ductal stricture. A prospective study on percutaneous catheter drainage of post‐necrotic pseudocysts (type I and II) was undertaken from 1987 to 1990. Twenty‐three pseudocysts in 21 patients were drained. Overall recurrence rate was 4%; 2 patients had fistulization of the catheter into bowel; no deaths occurred. The procedure was successful in all type I cysts; in type II cysts it was associated with prolonged drainage and increased risk of complications when cyst‐duct communication was present. Percutaneous drainage has no role to play in type III retention cysts. Guidelines regarding indications for treatment and the techniques employed are described.
Almost ASAP semantics: from timed models to timed implementations
Authors: Wulf Martin De , Doyen Laurent , Raskin Jean-François
Published: August 2005

In this paper, we introduce a parametric semantics for timed controllers called theAlmostASAP (as soon as possible) semantics. This semantics is a relaxation of the usual ASAP semantics (also called themaximal progress semantics) which is a mathematical idealization that cannot be implemented by any physical device no matter how fast it is. On the contrary, any correct Almost ASAP controller can be implemented by a program on a hardware if this hardware is fast enough. We study the properties of this semantics and show how it can be analyzed using the tool HyTech.
Decreased sensitivity to experimental pain in adjustment disorder
Authors: Bär Karl‐Jürgen , Brehm Stanislaw , Boettger Michael Karl , Wagner Gerd , Boettger Silke , Sauer Heinrich
Published: August 2005

An altered perception of pain has been described for several psychiatric disorders. To date the influence of adjustment disorders (AD) on pain perception has not been described.

Here, we investigated perception of experimentally induced pain in 15 patients suffering from AD (subtype with depressive symptoms) and controls matched for age and sex. Thresholds and tolerances were assessed for thermal and electrical pain on both sides of the body.

We found an overall increase of pain thresholds and tolerances in AD patients as compared to controls, predominately on the right side of the body. Analogue findings have been reported for pain perception in major depressive disorder (MDD). Of the data obtained, only thermal pain threshold on the right arm correlated with the severity of depressive symptoms.

Although the underlying pathology is elusive it is likely that the mechanisms for reduced pain sensitivity are comparable in MDD and AD.
Inhibition of the osteoclast V‐ATPase by small interfering RNAs
Authors: Hu Yingwei , Nyman Jonas , Muhonen Pirkko , Väänänen H. Kalervo , Laitala-Leinonen Tiina
Published: August 2005

The multisubunit enzyme V‐ATPase harbours isoforms of individual subunits. a3 is one of four 116 kDa subunit a isoforms, and it is crucial for bone resorption. We used small interfering RNA (siRNA) molecules to knock down a3 in rat osteoclast cultures. Labeled siRNA‐molecules entered osteoclasts via endocytosis and knocked down the a3 mRNA. Bone resorption was decreased in siRNA‐treated samples due to decreased acidification and osteoclast inactivation. Expression of a1 did not respond to decreased a3 levels, suggesting that a1 does not compensate for a3 in osteoclast cultures. Subunit a3 is thus an interesting target for novel nucleic acid therapy.
Up‐ and downregulated genes in muscles that undergo developmentally programmed cell death in the insect Manduca sexta
Authors: Löw Péter , Talián Gábor Csaba , Sass Miklós
Published: August 2005

This study was designed to investigate changes in gene expression associated with stage‐specific programmed cell death (PCD) in intersegmental muscles (ISMs) of the moth, Manduca sexta. The technique of differential display reverse transcription PCR was applied to compare mRNA levels before and after the onset of PCD in ISMs. Expression of E75B transcription factor was repressed while another factor, βFTZ‐F1, stayed at a very low level. However, gene coding for a translation‐initiation factor (eIF1A) was upregulated. Expression of these genes had not been previously reported to be altered in dying ISMs. An ecdysteroid agonist, RH‐5849, that prevented PCD in ISMs also blocked these changes.
The introduction of artificial structures on marine soft- and hard-bottoms: ecological implications of epibiota
Authors: BULLERI FABIO
Published: August 2005

Artificial structures, such as seawalls, breakwaters, jetties, pontoons and pier pilings are becoming ubiquitous features of landscape in shallow coastal waters of urbanized areas. Nonetheless, few published studies have focused on their ecology and little effort has been devoted to determine how the various objectives (economic, social and ecological) involved in their introduction into natural systems can be reconciled.
Recent freshening in the Kara Sea (Siberia) recorded by stable isotopes in Arctic bivalve shells
Authors: Simstich Johannes , Harms Ingo , Karcher Michael J. , Erlenkeuser Helmut , Stanovoy Vladimir , Kodina Lyudmila , Bauch Dorothea , Spielhagen Robert F.
Published: August 2005

Oxygen and stable carbon isotope records along the growth direction on shells of the bivalve species Astarte borealis and Serripes groenlandicus reliably record all important aspects of the bottom water hydrography in the shallow southeastern Kara Sea, despite uncertainties about the isotopic range due to sparse sampling and the possibility of growth rate changes. Changing freshwater supply from the rivers Ob and Yenisei is the main cause for seasonal temperature and salinity variations near the three sampling locations in 20 to 70 m water depth as suggested by CTD measurements and modeling. Peak winter salinity of the simulated hydrographic data series and peak winter values in the isotope records follow negative trends, which indicate a freshening of the bottom water due to an increasing fraction of river water during the 1990s. This freshening affected the whole Kara Sea, and coincided with a lowering of regional air pressure gradients, as indicated by the declining Arctic oscillation index. The resulting weakening of the prevailing southwesterly winds diminished the inflow of saline Atlantic‐derived water from the Barents Sea through the Kara Strait in the southwest, and, additionally, reduced the export of river water toward the north and northeast into the Arctic basin. Saline Atlantic‐derived water thus was replaced by freshwater, which was successively accumulated in the Kara Sea and accordingly imprinted on the stable isotope composition of the bivalve shells. The 1990s freshening in the Kara Sea thus may be caused by natural variations rather than being a signal for global change.
Interdecadal sea surface temperature–sea level pressure coupled variability in the South Pacific Ocean
Authors: Montecinos Aldo , Pizarro Oscar
Published: August 2005

The main coupled sea surface temperature (SST)‐sea level pressure (SLP) variability at interdecadal timescale in the South Pacific is studied by means of correlation and combined complex empirical orthogonal function (CCEOF) analyses. The SST‐SLP coupled variability presents a bidecadal cycle from mid‐1950s to 1970s and a decadal cycle from 1980s to early 1990s, reproducing the ENSO‐like interdecadal oscillation. Particularly, the first SST‐SLP CCEOF mode describes the bidecadal cycle characterized by westward progression of SST and SLP anomalies along the tropical Pacific, while the second SST‐SLP CCEOF mode shows the decadal cycle with eastward development. During both bidecadal and decadal cycles the SST fluctuations in the eastern equatorial Pacific and along the western coast of South America are primarily forced by equatorial zonal wind variability. Specially during the bidecadal cycle, the alongshore SST variability south of 30°S is maintained and reinforced by meridional coastal wind fluctuations associated with a stationary SLP pattern off southern Chile. This stationary SLP pattern appears connected to SST fluctuations in the central tropical Pacific.
Aquatic habitats and diffusion constraints affecting microbial coexistence in unsaturated porous media
Authors: Long Tao , Or Dani
Published: August 2005

Evidence suggests that the diversity of microbial life in the vadose zone exceeds diversity found in all other compartments of the biosphere. Such rich diversity is believed to be promoted by complexity of resource and microenvironments and by fragmentation of aquatic habitats in unsaturated soils that limit diffusion pathways and form physically isolated niches capable of supporting diverse species within small soil volumes. We investigated the role of heterogeneity of substrate diffusion through loosely connected water films in promoting coexistence of species that otherwise would not coexist under homogeneous conditions. The mesoscale modeling approach employed in this study tracks nutrient diffusion and consumption within a domain inhabited by microbial communities that expand and move about in response to spatial and temporal variations in nutrients and hydration conditions (termed active walkers). Numerical results on hypothetical rough surfaces support the hypotheses concerning the role of diffusion limitations in sustaining nutrient gradients and sheltering less competitive species, thereby promoting coexistence in heterogeneous domains.
Submicron sea spray fluxes
Authors: Geever Michael , O'Dowd Colin D. , van Ekeren Stefan , Flanagan Robert , Nilsson E. Douglas , de Leeuw Gerrit , Rannik Üllar
Published: August 2005

Eddy covariance aerosol flux measurements were conducted at the Mace Head coastal station in the North East Atlantic. Footprint and micrometeorological analysis under clean marine air mass conditions indicated that fluxes representative of open ocean conditions could be derived during high tide conditions and an oceanic fetch. Sea‐spray fluxes were derived for total particle sizes larger than 10 nm and total particle sizes larger than 100 nm (i.e. covering the Aitken and Accumulation mode). The source fluxes (F) were found to be strongly correlated with both wind speed (U) and friction velocity (u*), following, by convention, an exponential relationship (LogF = aU + c) relationship. Comparison of source fluxes at sizes larger than 10 nm and larger than 100 nm demonstrates that approximately 50% of the number flux can be attributed to the accumulation mode and 50% to the Aitken mode. At 10 ms−1 wind speeds, the total primary marine aerosol flux is of the order of 2 × 106 m−2 s−1, increasing to 20 × 106 m−2 s−1 at 20 ms−1.
El Niño induced anomalies in global data sets of total column precipitable water and cloud cover derived from GOME on ERS‐2
Authors: Wagner T. , Beirle S. , Grzegorski M. , Sanghavi S. , Platt U.
Published: August 2005

Global data sets of total column precipitable water and cloud cover derived from the Global Ozone Monitoring Experiment (GOME) are analyzed with respect to anomalies induced by the strong El Niño 1997/1998. In contrast to other satellite observations of water vapor, the GOME nadir observations in the visible spectral range are of similar sensitivity over both land and ocean. In addition, they are sensitive in particular to the water vapor concentration close to the surface where a major fraction of the water vapor column is present. Information on the atmospheric cloud cover was derived from the observed broadband intensity as well as the oxygen (O2) absorption. While the first quantity is mainly a measure of geometrical cloud fraction, the latter also yields information on the cloud altitude. We investigated the time series of monthly mean values as well as anomalies calculated for a 6‐month period during the El Niño 1997/1998. For all three quantities we found strong anomalies over large areas and for extended periods. Especially for the total column precipitable water, significant anomalies were found even in mid and high latitudes indicating substantial changes in the hydrological cycle and the global circulation patterns.
Solvation of sodium-chloride ion pair in water cluster at atmospheric conditions: Grand canonical ensemble Monte Carlo simulation
Authors: Zidi Z. S.
Published: August 2005

Open statistical ensemble simulations are used to study the mechanism of nucleation of atmospheric water on sodium-chloride ion pair in a wide range of temperature and relative humidity values. The extended simple point-charge model is used for water molecules. Ions-water nonadditive interactions are taken into account by introducing the mutual polarization of ions and water in the field of each other. Gibbs free-energy variations are calculated from Na+–Cl− pair-correlation function and used as a criterion for determining the possible stable states of the cluster. In this relation, it was found that the dissociation of ion pairs in water clusters occurs even at vapor pressures of only a few millibars. In the conditions under consideration solvent-separated ion-pair states are found to be more probable than contact ion-pair configurations. The susceptibilities of water and ions are found to play an essential role in the stabilization of ions at large separations. The structure of ion-induced clusters is analyzed in terms of binary correlation functions. The nonpair interactions influence essentially the structure of ion solvation shells. The results of simulation show that the separation of the charges in water clusters containing simple ions can take place under atmospheric conditions.
Threshold collision-induced dissociation of diatomic molecules: A case study of the energetics and dynamics of O2− collisions with Ar and Xe
Authors: Ahu Akin F. , Ree Jongbaik , Ervin Kent M. , Kyu Shin Hyung
Published: August 2005

The energetics and dynamics of collision-induced dissociation of O2− with Ar and Xe targets are studied experimentally using guided ion-beam tandem mass spectrometry. The cross sections and the collision dynamics are modeled theoretically by classical trajectory calculations. Experimental apparent threshold energies are 2.1 and 1.1eV in excess of the thermochemical O2− bond dissociation energy for argon and xenon, respectively. Classical trajectory calculations confirm the observed threshold behavior and the dependence of cross sections on the relative kinetic energy. Representative trajectories reveal that the bond dissociation takes place on a short time scale of about 50fs in strong direct collisions. Collision-induced dissociation is found to be remarkably restricted to the perpendicular approach of Ar∕Xe to the molecular axis of O2−, while collinear collisions do not result in dissociation. The higher collisional energy-transfer efficiency of xenon compared with argon is attributed to both mass and polarizability effects.