bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantum phenomena via complex measure: Holomorphic extension
Authors: Srinivasan S.K. 
Published: May 2006

AbstractThe complex measure theoretic approach proposed earlier is reviewed and a general version of density matrix as well as conditional density matrix is introduced. The holomorphic extension of the complex measure density (CMD) is identified to be the Wigner distribution function of the conventional quantum mechanical theory. A variety of situations in quantum optical phenomena are discussed within such a holomorphic complex measure theoretic framework. A model of a quantum oscillator in interaction with a bath is analyzed and explicit solution for the CMD of the coordinate as well as the Wigner distribution function is obtained. A brief discussion on the assignment of probability to path history of the test oscillator is provided.
New core configurations of the c‐edge dislocation in wurtzite GaN
Authors: Belabbas I. , Chen J. , Akli Belkhir M. , Ruterana P. , Nouet G. 
Published: May 2006

AbstractIn the framework of empirical potentials (Modified Stillinger‐Weber), we modelled and studied the energy and the core structure of the c‐edge basal dislocation in wurtzite GaN. Further to the core configurations already known, we report two new ones without wrong bonds. Our calculations show that the configurations containing wrong bonds are the most energetically favourable in both glide and shuffle sets. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Freestanding two inch c‐plane GaN layers grown on (100) γ‐lithium aluminium oxide by hydride vapour phase epitaxy
Authors: Richter E. , Hennig Ch. , Zeimer U. , Weyers M. , Tränkle G. , Reiche P. , Ganschow S. , Uecker R. , Peters K. 
Published: May 2006

Abstract(100) γ‐lithium aluminium oxide substrates of two inch diameter were fabricated from crystals grown by the Czochralski technique. Onto these substrates c‐plane GaN with a thickness of about 200 µm has been grown by hydride vapour phase epitaxy in a horizontal AIX HVPE reactor. The GaN layer spontaneously separates from the bottom lithium aluminium oxide substrate during the cool‐down resulting in complete freestanding 2 inch GaN wafers. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Characterization of structural defects in (11$ \bar 2 $0) GaN films grown on (1$ \bar 1 $02) sapphire substrates
Authors: Vennéguès P. , Mathal F. , Bougrioua Z. 
Published: May 2006

AbstractThe microstructure of (11‐20) GaN films grown on (1‐102) sapphire substrates is studied by transmission electron microscopy. The predominant defects emerging at the surface of a 1‐2 μm thick layers are basal stacking faults of I1 type (1/6<20‐23> displacement vector). These defects are either terminated in the films by partial dislocations with a 1/6<20‐23> Burgers vector or are connected to another basal stacking fault by a prismatic stacking fault with a 1/2<10‐11> displacement vector. All the stacking faults, originate from the interfacial region. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Information systems success in free and open source software development: theory and measures
Authors: Crowston Kevin , Howison James , Annabi Hala 
Published: May 2006

AbstractInformation systems success is one of the most widely used dependent variables in information systems (IS) research, but research on free/libre and open source software (FLOSS) often fails to appropriately conceptualize this important concept. In this article, we reconsider what success means within a FLOSS context. We first review existing models of IS success and success variables used in FLOSS research and assess them for their usefulness, practicality and fit to the FLOSS context. Then, drawing on a theoretical model of group effectiveness in the FLOSS development process, as well as an on‐line discussion with developers, we present additional concepts that are central to an appropriate understanding of success for FLOSS.In order to examine the practicality and validity of this conceptual scheme, the second half of our article presents an empirical study that demonstrates operationalizations of the chosen measures and assesses their internal validity. We use data from SourceForge to measure the project's effectiveness in team building, the speed of the project at responding to bug reports and the project's popularity. We conclude by discussing the implications of this study for our proposed extension of IS success in the context of FLOSS development and highlight future directions for research. Copyright © 2006 John Wiley & Sons, Ltd.
Glycogen storage diseases in animals and their potential value as models of human disease
Authors: Walvoort H. C. 
Published: May 2006

AbstractGlycogen storage diseases (GSD) are inborn errors of glycogen metabolism. Of the eight human GSD types in which the enzymatic deficiency has been identified, spontaneous animal counterparts have been reported for GSD I (glucose‐6‐phosphatase deficiency) in the mouse, for GSD II (acid α‐glucosidase deficiency) in the dog, in cattle and in the quail, for GSD III (debrancher enzyme deficiency) in the dog and for GSD VIII (phosphorylase kinase deficiency) in the rat and the mouse. Experimentally induced GSD‐like conditions have been described in the rat (Acarbose‐induced GSD II‐like conditions, iodoacetate‐induced symptoms of myophosphorylase (GSD V) and myophosphofructokinase (GSD VII) deficiency) and the chicken (ochratoxin A‐induced symptoms of cyclic AMP‐dependent protein kinase deficiency). Enzymatic defects that are typical of the human GSD types have not been clearly identified in the induced animal conditions. The homology of animal and human GSD types is discussed. It is concluded that clinical, pathogenic and therapeutic studies of GSD may benefit from the use of animal models. For genetic studies of human GSD these models may prove to be of limited value, as the picture of several human GSD types is already obscured by genetic heterogeneity.
Immunofluorescence staining and immunological studies of arylsulphatase a of multiple sulphatase deficiency (MSD) and metachromatic leukodystrophy (MLD) fibroblasts
Authors: Tanaka A. , Higami S. , Isshiki G. , Matsumoto T. , Furusawa M. 
Published: May 2006

AbstractMultiple sulphatase deficiency (MSD) and metachromatic leukodystrophy (MLD) are both characterized by a deficiency of arylsulphatase A (ARS A) activity, although they are inherited as separate autosomal recessive traits. However, it has been found that the immunologically active substance with anti‐ARS A antibody is present in quite normal levels in MLD and in smaller quantities in MSD fibroblasts (Fiddler, 1979).Indirect immunofluorescence staining with anti‐ARS A antibody displayed a coarse granular and diffuse distribution of ARS A or cross‐reacting material (CRM) in the normal control and MLD fibroblasts, whereas very weak fluorescence staining was observed in MSD fibroblasts proportional to the decrease in the ARS A activity observed in the lysate enzyme assay.These results suggest that ARS A deficiency in MLD cells is due to an enzymatically deficient ARS A molecule, which is immunologically cross‐reactive with anti‐normal ARS A antibody. ARS A deficiency in MSD cells appears to be due to a reduced amount of normal ARS A.
Restraint‐induced stress ulcer. II. biochemical and ultrastructural studies of gastric mucosa
Authors: Balibrea Jose L. , Merchan Jaime , Gomez Jose , Alemany Jose A. , Aznar Jose , Fariña Juliana , Barreno Pedro G. , Fernandez Jose L. , Prado Josefina 
Published: May 2006

AbstractThe aim of these studies was to evaluate the light and electron microscopic changes of the gastric mucosa of restrained rats, and to determine if there were correlations between structural changes, histidine decarboxylase activity, histamine content, and gastric secretion.In areas with high‐grade mucosal lesions, signs of functional hyperactivity of the oxyntic and chief cells and cytoplasmic degranulation of the enterochromaffin‐like cells were observed. These changes were not influenced by vagotomy. The hyperactivity of the chief cells was related to a higher proteolytic activity of the gastric juice and to an increased excretion of uropepsinogen (p<0.01). The hyperactivity of the oxyntic cells was not accompanied by an increase in total acidity, which could be explained by hydrogen ion back‐diffusion through a damaged gastric mucosal barrier. The increase in histidine decarboxylase activity (p<0.01) and the decrease of histamine content (p<0.01) in the glandular mucosa of restrained rats, together with the microscopic and ultrastructural observations, suggest that the early microcirculatory changes are due to local alterations in the metabolism of vasoactive amines.
Candida infection in surgical patients
Authors: Solomkin Joseph S. , Simmons Richard L. 
Published: May 2006

AbstractCandida infections have become a common and serious problem in non‐neutropenic general surgical patients. This paper reviews the etiologic factors, pathogenesis of systemic candidiasis, and the more common syndromes of infection in surgical patients. Prophylactic and systemic therapy is detailed. The most significant factor inCandida infections is depression of host immune function. Significant abnormalities of T‐cells, monocytes, and neutrophils have been described in patients with systemicCandida infection and in patients shown to be at high risk of such infection (burned, malnourished, or septic patients). Systemic infection is a consequence of high density colonization at 1 or more sites. Topical therapy with nystatin, amphotericin B, or the imidazole derivatives is usually effective in terminating local colonization of skin lesions, the gastrointestinal tract, or the bladder. If local colonization is not controlled, the patient may progress to systemic infection. The primary diagnostic difficulty is determining when conversions to systemic infection has occurred. Serologic testing and blood culture techniques appear to be of value only late in the course of infection. For this reason, the assessment of culture results from multiple sites appears to be of value. Treatment is begun with systemic amphotericin if the patient is immunodepressed or has ≥ 3 sites positive forCandida. In nonneutropenic patients, relatively short therapy appears effective. Treatment of endocarditis requires several (4–6) weeks of therapy, and current evidence suggests that early surgery with valve replacement may improve survival.
Surgical infections in drug addicts
Authors: Hau Toni , Kallick Charles A. 
Published: May 2006

AbstractInfectious complications are responsible for a majority of the medical and surgical hospital admissions and 15% of the deaths of drug addicts. The most common and serious complication is endocarditis, mostly of the right heart, caused by Staphylococci and/or gram‐negative rods. If the endocarditis is caused by the latter group of organisms, early operative intervention with excision of the tricuspid and/or replacement of the mitral and aortic valves is frequently necessary because of poor response to antibiotic treatment. Other complications of generalized sepsis are septic pulmonary emboli, which frequently gives rise to pulmonary abscesses, and splenic abscesses. Infections of the vascular system occur as either suppurative thrombophlebitis or mycotic aneurysms. Soft tissue infections in the form of subcutaneous abscesses, cellulitis, myositis, and necrotizing fasciitis are caused by a mixed flora consisting of gram‐positive and gram‐negative aerobes and anaerobes. The majority of patients with tetanus seen in large cities are drug addicts. Infections of the skeletal system are typically caused bySerratia marcescens orPseudomonas, and present as septic arthritis of the sternoclavicular or sacroiliac joints or osteomyelitis of the spine originating from a disc space infection.
The overwhelming postsplenectomy sepsis problem
Authors: Leonard Arnold S. , Giebink G. Scott , Baesl Thomas J. , Krivit William 
Published: May 2006

AbstractPostsplenectomy vulnerability to infection is not limited to age or disease process. Postsplenectomy infection is an emergency problem that requires immediate and accurate treatment because death is potential within a few hours of onset. Although the pathogenesis of overwhelming postsplenectomy sepsis is not completely understood, experimental evidence suggests that loss of mechanical filtration is more important than immunologic deficiences resulting from splenectomy. Certainly, a combination of both may be present. While no single measure seems to completely protect against overwhelming postsplenectomy sepsis, experimental evidence suggests that by reducing or minimizing the amount of spleen removed by newer surgical techniques, and by the addition of pneumococcal vaccine and prophylactic penicillin, the incidence of overwhelming sepsis can be reduced. Further evaluation of splenic function is necessary to assess the role of autotransplantation in the prevention of postsplenectomy sepsis (Fig. 1).
Predicting surgical infection before the operation
Authors: Meakins Jonathan L. , Pietsch John B. , Christou Nicolas V. , Maclean Lloyd D. 
Published: May 2006

AbstractTo date, simple skin testing using recall antigens has proven to be the most accurate method of assessing preoperative risk for serious infectious complications. When used in conjunction with measures to control the microorganisms and the environment, evaluation of host defense mechanisms with skin testing can aid in reducing postoperative infectious morbidity and mortality.There are 3 possible therapeutic approaches to anergic patients. Surgery and specific nonsurgical treatments (restoration of blood volume, red cell mass, antibiotics), total parenteral nutrition, and immunorestoration. The challenge for the future is to develop the criteria that will indicate the most important defects which account for the anergic state in individual patients.
Long‐term effects of bile on the gastric mucosa of the dog
Authors: Cardoso de Oliveira M. , Azevedo Isabel 
Published: May 2006

AbstractBile was allowed to act on the gastric mucosa of dogs for periods of time ranging from 60 to 540 days. Then the mucosa was studied by light microscopy and morphometric techniques to determine height of the mucosa, infundibulum and glands, number of mast cells, and number of interepithelial lymphocytes. Marked acute inflammatory lesions and decrease in cellular mucin content were observed mainly in the antral mucosa exposed to bile for up to 130 days. Other changes appearing both in the antrum and fundus of the same dogs included an increase in the number of interepithelial lymphocytes, architectural distortion, and decrease in the height of the mucosa, the infundibulum being the most affected component in the antrum and the glands in the fundus. Positive alkaline phosphatase activity was observed in the antral area up to 130 days. With continuous exposure to bile, the gastric mucosa appeared to undergo adaptation, since all the described alterations gradually disappeared.
Prevention of postoperative deep vein thrombosis in Sweden results of a survey
Authors: Bergqvist David 
Published: May 2006

AbstractAll 236 clinics in Sweden dealing with general, urologic, orthopedic, and gynecologic surgery were sent a questionnaire concerning their policy about prophylaxis against postoperative thromboembolism and 94% replied. Of these, 76% claimed that they use some kind of prophylaxis. Decisive factors for the adoption of routine prophylaxis and prophylactic methods in current use varied among the 4 surgical specialties surveyed. In spite of the evidence that age is the most important single risk factor for thromboembolic complications, only 45% of the clinics considered age to be important. The estimated frequency of prophylaxis among patients undergoing operations was only 19%. Side effects of prophylaxis were reported in 55% of the clinics. Dextran 70 and low‐dose heparin were the most frequently used prophylactic methods.
Contraction and the control of contraction
Authors: Rudolph Ross 
Published: May 2006

AbstractWound contraction is a basic mechanism for wound closure that can be lifesaving. Yet, wound contraction can also produce considerable deformity and misery in conditions as diverse as burn scar contracture, cirrhosis, Dupuytren's contracture, and contracture around silicone tissue implants. Current evidence suggests that wound contraction is a cellular function of contractile fibroblasts (myofibroblasts). These cells share the electron microscopic appearance of both fibroblasts and smooth muscle cells. Pharmacologically and immunologically, myofibroblasts have many characteristics of smooth muscle cells. Active wound contraction caused by myofibroblasts can lead to fixed, rigid scar contracture. Contracture associated with poor joint positioning can also occur passively due to collagen reorganization alone, without myofibroblast involvement.Control of contraction (and contracture) can be achieved theoretically by 3 modes of therapy. Physical means, including range of motion exercises, splinting, and full thickness skin grafting after surgical release, are used currently. Biochemical control of myofibroblast contraction by agents that affect tissue‐cultured fibroblasts has the potential of reducing wound contraction. Inhibition of collagen synthesis, inhibition of cross‐linking, or increased collagenolysis may eventually be clinically useful, and would be of value in controlling both contracture due to active wound contraction, and contracture due to passive positioning.
Management of graft infections following abdominal aortic aneurysm replacement
Authors: Bernhard Victor M. 
Published: May 2006

AbstractGraft infection following resection of an abdominal aortic aneurysm is a rare but highly lethal complication. It is most commonly associated with aortoenteric fistula or external contamination when graft limbs extend to the groin. Other sources are bowel or urinary tract entry, latent infection in the aneurysm wall, breaks in sterile technique, or bacteremia. Diagnosis should be suspected when a patient with an aortic graft develops unexplained fever, especially with back or abdominal pain, gastrointestinal bleeding of any kind, or metastatic infection to the limbs. Diagnosis is difficult to establish. Endoscopy to demonstrate erosion into the distal duodenum or to rule out other sources of bleeding was useful in all 6 patients in which it was employed. Positive arterial cultures distal to the graft, the finding of bilateral hydronephrosis, and demonstration of periaortic inflammation on gallium scan are highly suggestive. Aortography was helpful in 2 of 6 patients but was useless when negative. Barium contrast x‐ray studies were usually negative (90%) or confusing. Management requires excision of all infected graft material, usually the entire prosthesis. Restoration of limb circulation, usually with axillo femoral bypass, should be done in all patients except those with prior amputation or previous iliac artery or graft occlusion with adequate collaterals. A 35% patient survival rate was achieved in 20 patients with graft infection and aortoenteric fistula. However, when a correct diagnosis was made without delay and appropriate principles of management were instituted, 78% (7 of 9) patients survived and no amputations were required in the 5 patients with intact limbs. Prevention of postaneurysmectomy graft infection requires meticulous aseptic technique, effective graft coverage and separation from loops of bowel with viable tissue, and the use of prophylactic systemic and local antibiotics.
Small artery reconstruction with a new vascular prosthesis
Authors: Raithel Dieter , Groitl Heinrich 
Published: May 2006

AbstractIn the Surgical Department of the University of Erlangen, 307 reconstructions in all areas of the arterial tree were performed with PTFE (GORE‐TEX®) grafts, of which 188 were performed in the femoral‐popliteal and femoral‐crural areas. Femoral‐popliteal bypass grafts above the knee joint remained patent in 93% of the patients during an average follow‐up time of 6.7 months. Below the knee joint, the patency rate was 85% during an average follow‐up time of 5.6 months. In the proximal aorta, aorta‐renal, and aorta‐femoral areas, long‐term results with the PTFE graft have been excellent.
Transapical left ventricular bypass with local heparinization for prolonged circulatory support
Authors: Taguchi Kazumi , Murashita Junji , Nakagaki Mitsuru , Mochizuki Takaaki 
Published: May 2006

AbstractAn avcothanized vinyl sheet consisting of a Pall filter®, 2 pressure monitoring lines, 2 heparinization lines, and a roller pump was used for transapical left ventricular bypass in 36 calves and 11 patients. Blood was returned to the abdominal or ascending aorta or carotid artery. Prolonged left ventricular flow unloading was carried out. All 31 calves that underwent left ventricular bypass and 5 calves that underwent biventricular bypass survived the scheduled period of bypass of up to 7 weeks except for 2 calves that died of accidental air embolism and 2 that were deliberately sacrificed due to infection. Local heparinization for 6 days followed by oral anticoagulation to maintain the prothrombin time at 150–200% of normal were effective in keeping the animals from bleeding and preventing thromboembolism. Eleven critically ill patients with severe heart disease were supported with left or biventricular bypass for periods of up to 172 hours. Four patients ultimately recovered, and 3 others were successfully weaned from bypass and expired 1–4 months later.
Gallstone ileus: An analysis of 20 patients
Authors: Heuman Rolf , Sjödahl Rune , Wetterfors Jarl 
Published: May 2006

AbstractAn analysis of 20 patients with gallstone ileus treated at the University Hospital in Linköping during a 10‐year period is presented. The patients had a median age of 75 years and 70% were women. The symptomatology was usually vague and consisted of diffuse abdominal pain, often accompanied by vomiting. The delay before admission to the hospital averaged 4 days. Radiography with both plain abdominal x‐rays and a barium meal showed mechanical intestinal obstruction in all but 1 patient and gallstone ileus was diagnosed before laparotomy in 60% of patients. Enterolithotomy was performed in all patients but there was no surgery on the gallbladder and/or the fistula. The frequency of postoperative wound infection was 25%. There was only 1 death, a mortality rate of 5%. It is our opinion that the low mortality was due to early diagnoses, careful preoperative preparation, an operative procedure aiming only at relief of the obstruction, and improved anesthesia and prophylactive short‐term antibiotics. The only indication for an elective cholecystectomy is persistent symptoms of gallbladder disease.