bluuebunny/crossref_metadata_2025 huggingface dataset:
Small groups' ecological reasoning while making an environmental management decision
Authors: Hogan Kathleen
Published: August 2002

The objective of this study was to explore the ideas and reasoning students use to make a collaborative environmental management decision. Eight groups of 8th‐grade students (n = 24) considered ecological and economic information about an invasive aquatic species to make a management recommendation. In addition to discussing the exact information they were given, the groups made a variety of interpretations, elaborations, and inferences concerning ecological structure and dynamics and practical aspects of the management scenario. Value judgments and concerns with uncertainty also appeared in students' discussions, to differing degrees. The students' discussions were compared with scientists' guidelines for making environmental management decisions, and with one expert's analysis of the particular management scenario the students considered. A major finding was that whereas across groups students touched on all of the themes that scientists consider to be important for making environmental management decisions, within most groups students focused more narrowly on particular themes, giving cursory treatment to other dimensions of the problem. The results point to a need to foster students' ecological background knowledge and integrative, systems thinking skills for making principled decisions about complex environmental issues. © 2002 Wiley Periodicals Inc. J Res Sci Teach 39: 341–368, 2002
Promoting understanding of chemical representations: Students' use of a visualization tool in the classroom
Authors: Wu Hsin‐Kai , Krajcik Joseph S. , Soloway Elliot
Published: August 2002

Many students have difficulty learning symbolic and molecular representations of chemistry. This study investigated how students developed an understanding of chemical representations with the aid of a computer‐based visualizing tool, eChem, that allowed them to build molecular models and view multiple representations simultaneously. Multiple sources of data were collected with the participation of 71 eleventh graders at a small public high school over a 6‐week period. The results of pre‐ and posttests showed that students' understanding of chemical representations improved substantially (p < .001, effect size = 2.68‐. The analysis of video recordings revealed that several features in eChem helped students construct models and translate representations. Students who were highly engaged in discussions while using eChem made referential linkages between visual and conceptual aspects of representations. This in turn may have deepened their understanding of chemical representations and concepts. The findings also suggest that computerized models can serve as a vehicle for students to generate mental images. Finally, students demonstrated their preferences of certain types of representations and did not use all types of three‐dimensional models interchangeably. © 2001 John Wiley & Sons, Inc. J Res Sci Teach 38: 821–842, 2001
Students' science perceptions and enrollment decisions in differing learning cycle classrooms
Authors: Cavallo Ann M.L. , Laubach Timothy A.
Published: August 2002

This investigation examined 10th‐grade biology students' decisions to enroll in elective science courses, and explored certain attitudinal perceptions of students that may be related to such decisions. The student science perceptions were focused on student and classroom attitudes in the context of differing learning cycle classrooms (high paradigmatic/high inquiry, and low paradigmatic/low inquiry). The study also examined possible differences in enrollment decisions/intentions and attitudinal perceptions among males and females in these course contexts. The specific purposes were to: (a) explore possible differences in students' decisions, and in male and female students' decisions to enroll in elective science courses in high versus low paradigmatic learning cycle classrooms; (b) describe patterns and examine possible differences in male and female students' attitudinal perceptions of science in the two course contexts; (c) investigate possible differences in students' science perceptions according to their decisions to enroll in elective science courses, participation in high versus low paradigmatic learning cycle classrooms, and the interaction between these two variables; and (d) examine students' explanations of their decisions to enroll or not enroll in elective science courses. Questionnaire and observation data were collected from 119 students in the classrooms of six learning cycle biology teachers. Results indicated that in classrooms where teachers most closely adhered to the ideal learning cycle, students had more positive attitudes than those in classrooms where teachers deviated from the ideal model. Significantly more females in high paradigmatic learning cycle classrooms planned to continue taking science course work compared with females in low paradigmatic learning cycle classrooms. Male students in low paradigmatic learning cycle classrooms had more negative perceptions of science compared with males in high paradigmatic classrooms, and in some cases, with all female students. It appears that using the model as it was originally designed may lead to more positive attitudes and persistence in science among students. Implications include the need for science educators to help teachers gain more thorough understanding of the learning cycle and its theoretical underpinnings so they may better implement this procedure in classroom teaching. © 2001 John Wiley & Sons, Inc. J Res Sci Teach 38: 1029–1062, 2001
Symbiotic International Business Networks: Collaboration between Small and Large Firms
Authors: Etemad Hamid , Wright Richard W. , Dana Leo Paul
Published: August 2002

As the drivers of globalization remove barriers that traditionally segmented the competitive environments of
small and large firms, firms of all sizes are beginning to share the same competitive space. Symbiotic
arrangements are evolving through which smaller firms enter the value chains of larger firms, to the benefit of
both sides. Using a conceptual framework with illustrative examples, this article explains how smaller firms can
use symbiotic, collaborative arrangements with larger firms to overcome inherent constraints of size and to
achieve the efficiencies required for world‐class competitiveness. © 2001 John Wiley &
Sons,Inc.
Hexokinase PII: structural analysis and glucose signalling in the yeast Saccharomyces cerevisiae
Authors: Mayordomo Isabel , Sanz Pascual
Published: August 2002

Hexokinase PII (Hxk2) is a yeast glucose phosphorylating enzyme that, besides its role in glycolysis, seems to have an additional role in glucose signalling. To study the domains in Hxk2 that may participate in this latter process, we have constructed 11 mutant alleles using site‐directed mutagenesis. Six of them were clustered charged‐to‐alanine mutants in which clusters of charged residues were changed to alanine residues. Two of them contained substitutions in Ser15 to either alanine or glutamic acid and three of them had deletions at either the N‐terminus or the C‐terminus of the protein. In most of them, the catalytic activity correlated directly with their functionality in glucose signalling. However, we found two mutants (Δ1–15 and Δ476–486) that, having low catalytic activity, were still fully functional in glucose signalling. This may indicate that other factors and not just the catalytic activity of the enzyme may be important for the functionality of the protein in glucose signalling. Copyright © 2001 John Wiley & Sons, Ltd.
Identification of a Candida glabrata homologue of the S. cerevisiaeVRG4 gene, encoding the Golgi GDP‐mannose transporter
Authors: Nishikawa Akiko , Mendez Barbara , Jigami Yoshifumi , Dean Neta
Published: August 2002

Mannoproteins on the cell wall of yeast and fungi help regulate cell shape, porosity, and cell–cell interactions, including those required for attachment to host cells by fungal pathogens. The mannose‐containing oligosaccharides on proteins and lipids are extended in the Golgi by glycosyltransferases that use GDP‐mannose as the sugar substrate. A membrane‐bound transporter that, in Saccharomyces cerevisiae, is encoded by the VRG4 gene catalyses delivery of GDP‐mannose into the lumen of the Golgi. We report here the cloning of the homologous VRG4 gene from the pathogenic yeast, Candida glabrata, by functional complementation of an S. cerevisiae vrg4 mutant. The sequence of the CgVrg4 protein displays significant homology to GDP‐mannose transporters from other yeast, fungi, protozoa, and plants. CgVRG4 fully complements the glycosylation defect and other cell wall associated vrg4 mutant phenotypes. Like ScVRG4, CgVRG4 is essential for the viability of C. glabrata. These results suggest that, as in S. cerevisiae, CgVrg4p accounts for all of the GDP‐mannose transport activity in the Golgi lumen. The GenBank Accession No. for CgVRG4 is #AF360395. Copyright © 2002 John Wiley & Sons, Ltd.
Body weights of ruffed lemurs (Varecia variegata) in European zoos with reference to the problem of obesity
Authors: Schwitzer Christoph , Kaumanns Werner
Published: August 2002

Qualitative observations in several European zoos revealed a high proportion of obese individuals in different species of lemurs. This phenomenon was examined in both subspecies of the ruffed lemur (Varecia variegata variegata and Varecia variegata rubra). Data on body weight were obtained from 43 animals in 13 European zoos and were compared with body weights of wild ruffed lemurs. The captive individuals’ mean weight was significantly higher than either of two different samples of wild V. variegata variegata. Using a weight‐based definition of obesity, 46.5% of the individuals in our sample were obese. Neither significant differences in body weight between the two subspecies nor between sexes could be found. Body weight did not correlate with age.

The findings are discussed with reference to the feeding ecology of ruffed lemurs and their nutrition in captivity and to implications for captive breeding programs for this species. Zoo Biol 20:261–269, 2001. © 2001 Wiley‐Liss, Inc.
Breast Microcalcifications: Multivariate Analysis of Radiologicand Clinical Factors for Carcinoma
Authors: Fondrinier Eric , Lorimier Gérard , Guerin‐Boblet Véronique , Bertrand Andrée‐Françoise , Mayras Claude , Dauver Nicolette
Published: August 2002

Screening mammography contributes to theimprovement of breast carcinoma survival through early detection andtreatment of non‐palpable lesions. Microcalcifications are offundamental importance in this process. The percentage of malignantlesions found in biopsies for microcalcifications varies from 10% to40%. The purpose of this study was to evaluate the relationshipbetween clinical and radiologic records and the presence of malignantbreast diseases. To establish the basis for the study, 211 mammographicfiles showing clustered microcalcifications from 204 women wereprospectively reviewed and clinical records were retrospectively drawn.Definitive pathologic analysis was available for all. The value forcancer of each criterion was investigated by univariate andmultivariate analyses. A first analysis was performed on the entirepopulation and a second one was performed with stratification onmorphologic subgroups. There were 99 malignant lesions (47%). In theentire group, no clinical criterion was significant. In the univariateanalysis, five radiologic variables were significant: morphologic type(p < 0.0001), number of calcifications per cluster(p < 0.0001), linear or triangular distribution(p < 0.0002), diameter of the area (p < 0.01),and number of clusters (p = 0.011). In themultivariate analysis, two criteria remained significant: morphologictype 4 (irregularly punctiform) or 5 (vermicular) microcalcifications(Le Gal’s classification) (p < 0.0001) and diameter of thecluster larger than 25 mm (p = 0.032). In subgroups,in the multivariate analysis, the "age > 60 years" criterion wasstatistically significant in the group of regular punctiformmicrocalcifications (type 2); for irregularly punctiformmicrocalcifications (type 4), "number of microcalcifications > 20" was significant. The morphologic features of microcalcifications mustbe the first criterion evaluated. They permit identification ofcharacteristically benign (annular calcifications) or malignantcalcifications (vermicular calcifications). For the remainder of thecalcification types, other criteria must be taken into account, and their value vary with (according to) themorphologic aspect. These findings have implications for the managementof women with microcalcifications and could help breast specialistsmake treatment decisions.
Comparison of the Functional Outcome after Pylorus‐preservingPancreatoduodenectomy: Pancreatogastrostomy and Pancreatojejunostomy
Authors: Jang Jin‐Young , Kim Sun‐Whe , Park Sang‐Jae , Park Yong‐Hyun
Published: August 2002

To determine if there is any differencein pancreatic function after pylorus‐preserving pancreatoduodenectomy(PPPD) according to the type of pancreatoenterostomy[pancreatojejunostomy (P‐J) or pancreatogastrostomy (P‐G)], weevaluated the long‐term functional status of 34 patients who underwentPPPD and survived for more than 1 year without clinical evidence ofrecurrence. Altogether 20 patients underwent P‐J and 14 P‐G. To comparethe two groups, we analyzed the (1) general nutritional status; (2)quality of life using three scoring systems; (3) gastrointestinalsymptoms; and (4) pancreatic exocrine function by the stool elastase Itest and endocrine function by oral glucose tolerance test (GTT). AfterPPPD, body weight decreased in both groups, with no difference betweenthe two groups. No statistical differences were found in tricepsskinfold thickness or serum protein/albumin. Regarding the quality oflife and postoperative gastrointestinal symptoms, there were nodifferences between the two groups except steatorrhea. There were 4mild and 15 severe cases of pancreatic exocrine insufficiency amongthose who underwent P‐J, whereas all of the patients who underwent P‐Gshowed severe pancreatic insufficiency. On GTT, excluding preoperativediabetes patients, 43.8% (7/16) of the P‐J group had abnormal resultsafter surgery, whereas, 75.0% (9/12) of the PG group had an abnormalpostoperative GTT (p = 0.11). Severe exocrine andendocrine pancreatic insufficiency developed after PPPD in both the P‐Jand P‐G groups, but there was more functional deterioration in the P‐Ggroup than in the P‐J group. General nutritional status and quality oflife were not affected by the pancreatoenterostomy method in eithergroup.
Expanding Role of Fine‐needle Aspiration Cytology in Thyroid Diagnosis and Management
Authors: Werga Petra , Wallin Göran , Skoog Lamberth , Hamberger Bertil
Published: August 2002

In non‐iodine‐deficient areas, 4% to 7% of the population are reported to have thyroid abnormalities. Prophylactic operations of these nodules in the thyroid are not indicated and not cost‐effective, as at least four of five nodules are colloid goiter and only a few are malignant. The need for a reliable preoperative diagnosis is great, and fine‐needle aspiration (FNA) is now considered the first choice during workup for thyroid nodules. The steps in the FNA procedure are clinical examination and localization of the target lesion, aspiration, preparation of smears, and collecting material for ancillary microscopy techniques. All these steps must be exercised to allow optimal use of FNA. It can also be combined with various other methods, such as immunohistochemistry of thyroglobulin and calcitonin, analysis of nuclear DNA, DNA preparation for molecular biology analyses, and magnetic resonance spectra. The accuracy of the clinical routine in our unit was evaluated by studying the 5‐year outcomes of almost 4000 FNAs of the thyroid. The results were good, with only a few false‐negative and false‐positive results; but the problem of differentiating follicular adenoma from follicular carcinoma remains a significant problem. It is now well established that FNA biopsy and cytology is the best modality available for the workup of thyroid nodules and is widely utilized in endocrine surgical centers worldwide.
Effect of CO2 Pneumoperitoneum on Growth of Liver Micrometastases in a Rabbit Model
Authors: Ishida Hideyuki , Murata Nobuo , Yamada Hirofumi , Nomura Tomohisa , Shimomura Kazuyuki , Fujioka Masashi , Idezuki Yasuo
Published: August 2002

Little is known about the risk of metachronous liver metastases following laparoscopic resection for gastrointestinal malignancies. The effect of CO2 pneumoperitoneum on the growth of established liver micrometastases was investigated in a rabbit model. Male Japanese white rabbits weighing 2.8 to 3.3 kg were randomized to three groups (n= 15 per group) 3 days following intraportal inoculation of a tumor suspension containing 5 × 104 cells of VX2 cancer. In the pneumoperitoneum group, insufflation with CO2 was maintained at a pressure of 10 mmHg for 30 minutes. In the laparotomy group the abdominal cavity remained open through a 45 mm midline incision for 30 minutes; in the control group no treatment other than anesthesia was performed. Cancer nodules on the liver surface were compared among the three groups on day 17. There was no difference in the number of cancer nodules among the groups (p= 0.72). A significant difference in the total area of cancer nodules (mean ± SEM) was found only between the pneumoperitoneum group (696.0 ± 177.0 mm2) and the control group (247.2 ± 60.7 mm2) (p < 0.05). The frequency of cancer nodules larger than 3.0 mm in maximal diameter tended to be highest in the pneumoperitoneum group (p= 0.053). These results suggests that CO2 pneumoperitoneum may promote the growth of established liver micrometastases in this animal model.
Ingredients of Organ Dysfunction or Failure
Authors: Gullo A. , Berlot G.
Published: August 2002

The simultaneous dysfunction of several organs (MODS, or multiple organ dysfunction) represents the most challenging task for the intensivist. In recent years more and more patients have been diagnosed as suffering from MODS due to several causes, including better immediate treatment of injuries that only a few years ago would have been considered incompatible with life or with consequent reduced organ reserve. Even if initially MODS has been associated with infections and sepsis, because of its similarity with a generalized inflammatory reaction mediated by a wide array of mediators, it is now clear that noninfectious insults, such as multiple trauma, acute pancreatitis, and retroperitoneal bleeding, can start a chain reaction ultimately leading to the onset of MODS. A specific trigger factor has not yet been identified, but experimental and clinical evidence suggests that the gut, endothelium, and immune system interact to produce the altered metabolic and cardiorespiratory patterns commonly observed in patients with MODS. It is thus possible that a target‐oriented approach, including rapid correction of intestinal underperfusion, supply of specific nutrients, and down‐regulation of the inflammatory cascade, can act as either a preventive measure for subjects at risk or as a main treatment for patients with full‐blown MODS.
Intussusception in Children: International Perspective
Authors: Meier Donald E. , Coln C. Dale , Rescorla Frederick J. , OlaOlorun Akintayo , Tarpley John L.
Published: August 2002

Fifty consecutive cases of children with intussusception treated at a hospital in a developing country were compared with 50 consecutive cases treated at an American inner city children’s hospital and 50 consecutive cases treated at an American referral children’s hospital. The plan was to recommend ways of improving the treatment of children with intussusception in the developing world. Nonoperative reduction was attempted in the two American hospitals but was not available in the developing world hospital where all children were treated operatively. Children in the developing world hospital had a significantly longer duration of symptoms, an increased incidence of nonviable bowel, and a mortality of 18%. There were no deaths in either American hospital. The poorer outcome for developing world children was related to delay in treatment, the higher incidence of nonviable bowel, and the lack of adequate nursing care for acutely ill children. The use of nonoperative reduction would not have significantly improved the mortality rate among the developing world children. The mortality can best be reduced by: (1) earlier recognition and treatment of the intussusception; and (2) improvement in the postanesthetic care with better monitoring leading to prompt recognition and treatment of postoperative complications.
Combined Gunshot Injuries of the Trachea and Esophagus
Authors: Weiman Darryl S. , Pate James W. , Walker William A. , Brosnan Kathleen M. , Fabian Timothy C.
Published: August 2002

During an 8‐year period between 1985 and 1993, twelve patients were treated with combined gunshot wounds to the trachea and esophagus. All patients survived, but there were complications, including one tracheoesophageal fistula. Combined injuries of the trachea and esophagus should be repaired primarily, and drains do not necessarily have to be placed. The benefit of a muscle flap placed between the repairs was not confirmed in this series. Complications should be recognized early and treated aggressively to minimize damage to the airway.
Endoscopic Sphincterotomy: 7‐Year Experience
Authors: Lo Chung‐Yau , Lai Edward C.S. , Lo Chung‐Mau , Mok Francis P.T. , Chu Kent‐Man , Liu Chi‐Leung , Fan Sheung‐Tat
Published: August 2002

The present study documents the indications and results of endoscopic sphincterotomy (ES) performed over 7 years in a surgical endoscopy unit. Potential improvement of results over this time period was analyzed. ES was associated with rare but undesirable morbidity and mortality. Specific improvement of results over time has not been reported. ES was attempted in 706 patients (336 men, 370 women) from 1987 to 1994 and was accomplished in 689 patients (97.6%). Complications occurred in 50 patients (7.1%), 13 of whom required emergency operative intervention. The overall 30‐day mortality was 4.7% (n= 33), and procedure‐related mortality was 0.7% (n= 5). There was a significant decrease in hospital mortality (p< 0.01) and operative intervention for procedure‐related complications (p< 0.001) after 1990. Procedure‐related mortality has been reduced from 1.3% to 0.3% since 1990 (p= 0.1). ES in emergency situations or for malignant biliary obstruction did not adversely affect the outcome. It was concluded that ES can be performed safely in most patients. With increasing experience, procedure‐related morbidity and mortality can possibly be reduced.
Clinical Trials and Projected Future of Liver Xenotransplantation
Authors: Fung John , Rao Abdul , Starzl Thomas
Published: August 2002

The trial and error of the pioneering xenotransplant trials over the past three decades has defined the limitation of the species used. Success was tantalizingly close with the chimpanzee, baboon, and other primates. The use of more disparate species has been frustrated by the xenoantibody barrier. Future attempts at clinical xenotransplantation will be hampered by the consideration of the species of animals and the nature of the organs to be transplanted. On one hand, primate donors have the advantage of genetic similarity (and therefore potential compatibility) and less risk of immunologic loss. On the other hand, pig donors are more easily raised, are not sentient animals, and may be less likely to harbor transmissible disease. It is recognized that the success of xenotransplantation may very with different organs. Because it is relatively resistant to antibody‐mediated rejection, the liver is the organ for which there is the greatest chance of long‐term success. Consideration of using xenotransplants on a temporary basis, or as a “bridge” to permanent human transplantation, may allow clinical trials utilizing hearts or kidney xenografts. Issues on metabolic compatibility and infection risks cannot be accurately determined until routine success in clinical xenotransplantation occurs. Based on a limited experience, the conventional approaches to allotransplantation are unlikely to be successful in xenotransplantation. The avoidance of immediate xenograft destruction by hyperacute rejection, achieved using transgenic animals bearing human complement regulatory proteins or modulating the antigenic target on the donor organ, is the first step to successful xenotransplantation. The ability to achieve tolerance by establishing a state of bone marrow chimerism is the key to overcoming the long‐term immunologic insults and avoiding the necessarily high doses of nonspecific immunosuppression that would otherwise be required and associated with a high risk of infectious complications. Xenotransplantation faces criticism that is strongly reminiscent of that leveled against human‐to‐human transplantation during the late 1960s and early 1970s. Yet with persistence, the field of human‐to‐human transplantation has proved highly successful. This success was the result of a stepwise increase in our understanding of the biology of rejection, improvements in drug management, and experience. It is possible that xenotransplantation may not be universally successful until further technologic advances occur; yet cautious exploration of xenotransplantation appears warranted to identify those areas that require further study.
Gene Rearrangement of Immunoglobulin as a Marker of Thyroid Lymphoma
Authors: Matsuzuka Fumio , Fukata Shuji , Kuma Kanji , Miyauchi Akira , Kakudo Kenichi , Sugawara Masahiro
Published: August 2002

Thyroid lymphoma occurs most commonly in the thyroid gland in association with Hashimoto's thyroiditis. Histologic findings occasionally cannot distinguish lymphoma from Hashimoto's thyroiditis, which creates a serious problem of whether treatment should be initiated. For this study, we examined 33 lymphoma tissues and 10 thyroid tissues from patients with Hashimoto's thyroiditis for the presence of gene rearrangement of immunoglobulin, which represents clonality of B‐cell‐derived tumors. Genomic DNA from thyroid tissues was digested with Bam H1 and Hind III restriction enzymes followed by electrophoresis. A Southern blot was performed with an IgH‐JH probe or IgL‐Jκ probe to detect gene rearrangement. Of the 33 lymphoma tissues, 27 (85%) showed gene rearrangement of immunoglobulin, whereas none of Hashimoto's thyroiditis tissue showed gene rearrangement. Five patients with a positive histologic diagnosis of lymphoma showed a negative gene rearrangement and were treated as having lymphoma. We encountered one case of lymphoma (plasmacytoma) in which gene rearrangement (not histologic findings) was diagnostic. Gene rearrangement of immunoglobulin can be used to detect thyroid lymphoma, particularly when the histologic diagnosis is inconclusive. The sensitivity of detecting thyroid lymphoma by the Southern blot method was about 85% in the present series.
Effects of Surgical Sympathectomy on Skin Blood Flow in a Rat Model of Chronic Limb Ischemia
Authors: van Dielen François M.H. , Kurvers Harrie A.J.M. , Dammers Ruben , oude Egbrink Mirjam G.A. , Slaaf Dick W. , Tordoir Jan H.M. , Kitslaar Peter J.E.H.M.
Published: August 2002

The role of lumbar sympathectomy in the treatment of limb ischemia secondary to arteriosclerosis obliterans has been controversial. Increased temperature and rubor of the skin, which usually follow sympathectomy, have generally been interpreted as indicative of improved nutritive skin blood flow. However, the existence of a (nonnutritive) thermoregulatory level of skin microcirculation makes such an extrapolation questionable. We investigated the total (mainly thermoregulatory) skin blood flow (TSBF) in the hindlimb of 15 male Lewis rats by means of laser Doppler flowmetry and the nutritive skin blood flow (NSBF) by means of capillary microscopy (red blood cell velocity). Transcutaneous oximetry was used to assess skin oxygenation (SO). Measurements were performed before and 2 and 28 days after ligation of the common iliac and iliolumbar artery. Subsequently, either a surgical resection of the sympathetic chain (L2–L6) was performed or a sham operation. Measurements were repeated 2 and 28 days later. For the group of 15 rats as a whole, TSBF (p < 0.05), NSBF (p < 0.05), and SO (p < 0.05) were found to be drastically reduced at day 2 after ligation compared to preligation values. This reduction partially recovered during the following weeks. TSBF (p < 0.05) and NSBF (p < 0.05), however were still reduced at day 28 after ligation compared to preligation values, whereas the SO at this time tended to be lower (p= 0.11). In the sympathectomy group the TSBF was found to be increased at day 2 (p < 0.05) and day 28 (p < 0.05) after sympathectomy, both compared to values obtained at day 28 after ligation. Sympathectomy did not have an effect on NSBF and SO. The sham procedure had no effect on the TSBF, NSBF, or SO. These results indicate that in case of lower limb ischemia, sympathectomy improves skin blood flow at the thermoregulatory but not the nutritive level of skin microcirculation. This may be related to the fact that the thermoregulatory vessels are mainly sympathetically controlled, whereas the nutritive capillaries are mainly controlled by local (nonneural) factors.
Influence of Brain Death and Cardiac Preservation on Systolic and Diastolic Function and Coronary Circulation in the Cross‐circulated Canine Heart RID="" ID="" This International Society of Surgery (ISS)/Société Internationale de Chirurgie (SIC) article was presented at the 37th World Congress of Surgery International Surgical Week (ISW97), Acapulco, Mexico, August 24–30, 1997.
Authors: Szabó Gábor , Sebening Christian , Hackert Thilo , Hoffmann Lutz , Sonnenberg Karin , Hagl Christian , Tochtermann Ursula , Vahl Christian F. , Hagl Siegfried
Published: August 2002

Previous studies have demonstrated hemodynamic instability and cardiac dysfunction in the brain‐dead organ donor. It remains unclear if primary cardiac dysfunction is responsible for hemodynamic deterioration or decreased cardiac function is secondary to brain death‐associated altered loading conditions. Therefore in the present study the effects of brain death on hemodynamics and cardiac function were analyzed in vivo in an open chest model and ex vivo in a cross‐circulated heart preparation. In a second protocol, the impact of brain death‐associated hemodynamic changes on postischemic graft function was investigated. Brain death was induced injecting saline in a subdural Foley catheter. Induction of brain death led to a hyperdynamic reaction followed by hemodynamic deterioration with a decrease of systemic vascular resistance and myocardial contractility. If the hearts were explanted and assessed ex vivo, no differences were found between control and brain‐dead hearts. Furthermore, both control and brain‐dead hearts showed full functional recovery after 4 hours of hypothermic ischemic storage. Despite hemodynamic deterioration in situ after brain death, there were no differences between the postischemic function of control and brain‐dead hearts. These results indicate that myocardial dysfunction is not irreversible and may be secondary to altered loading conditions, and that the recovery of cardiac function after long‐term hypothermic storage is not impaired by the hemodynamic changes observed in situ after brain death induction. These data may also indicate that potential donor hearts might not be excluded from transplantation on the basis of impaired hemodynamic characteristics, especially if they are evaluated by load‐dependent parameters.
Pylorus‐preserving Pancreaticoduodenectomy versus Conventional Whipple Operation
Authors: Di Carlo Valerio , Zerbi Alessandro , Balzano Gianpaolo , Corso Vittorio
Published: August 2002

During 1990 to 1997 a series of 39 patients underwent a classic pancreaticoduodenectomy and 74 a pylorus‐preserving pancreaticoduodenectomy for pancreatic adenocarcinoma. The two groups had similar tumor characteristics and received comparable adjuvant treatments. No significant differences were found between the two groups in terms of mortality, morbidity, gastric emptying, food intake resumption, and hospital stay. Postoperative survival was not affected by the preservation of the pylorus, determined by both univariate and multivariate analyses. Postoperative nutritional outcome was similar in the two groups, although patients receiving adjuvant chemotherapy had a better nutritional recovery if the whole stomach was preserved. In our opinion pylorus‐preserving pancreatoduodenectomy is the treatment of choice of pancreatic head cancer.
APON's First 25 Years: A Lighter Look from the past Presidents
Authors: Walker Carolyn L.
Published: August 2002

This report uses an oral history methodology to look back at 25 years of the Association of Pediatric Oncology Nurses (APON) from the perspective of the past presidents. The different roles and responsibilities of the president and how they have evolved over the years are identified. Amusing, behind-the-scenes anecdotes from different presidential terms are revealed.
Using Research to Change Practice: Enteral Feedings for Pediatric Oncology Patients
Authors: Deswarte-Wallace Joetta , Firouzbakhsh Shahin , Finklestein Jerry Z.
Published: August 2002

This report details a study whose purpose was to show the safety of and describe the clinical and financial outcomes of nasogastric (NG) and nasojejeunal (NJ) tube feedings for nutritional support during and after intensive treatment for cancer. During a 17-month period, NG or NJ tubes were inserted in 25 patients who experienced, or were anticipated to experience, suboptimal nutrition during or after their chemotherapy (n = 14), radiation therapy (n = 2), or chemotherapy plus radiation (n = 5), after bone marrow transplant (n = 2), and as a result of neurological impairment (n = 2). Patient ages ranged from 1 month to 14 years. NG/NJ tubes were used for a total of 1415 patient days (median 40 days). Of those, 756 days occurred in the hospital (median, 18 days) and 659 were outpatient days (median = 12 days). Total parenteral nutrition (TPN) was used during 104 patient days (range, 1 to 35 days), and combination NG/NJ feedings were given with TPN for a total of 101 days. A comparable number of days of TPN therapy for the NG-fed patients would have cost $177,390 (average $135/day), compared with $65,700 (average, $50/day) for enteral feedings, for a savings of $111,690. Ten patients experienced grade 2 to 3 diarrhea and/or vomiting during the study. No untoward outcomes were identified. Enteral feedings were found to be a safe and cost-effective method for providing nutrition to these children with cancer.
Reduction and Temporary Stabilization of Acetabular Fractures Using ASIF Mandibular Reduction Forceps: Technique and Results Using Plate Fixation in 25 Dogs
Authors: Boswell Kimberly A. , Boone Ernest G. , Boudrieau Randy J.
Published: August 2002

Objective— To report the results of acetabular fracture fixation in 25 dogs in which a specialized forceps (ASIF mandibular reduction forceps, Synthes USA, Paoli, PA) was used to obtain fracture reduction and stabilization.

Study Design— A retrospective clinical study.

Animal Population— Twenty‐five client‐owned dogs with traumatic acetabular fractures.

Methods— The mandibular reduction forceps (MRF) use a screw on each side of the fracture to attach the clamp directly to the bone and permit direct manipulation of the fragments. Medical records from 25 dogs with acetabular fractures were reviewed to determine the effectiveness of this technique in obtaining, and then maintaining, fracture reduction while a plate was being applied.

Results— Clinical results were considered successful in 24 of 25 dogs; the small size of 1 dog prevented application of the MRF. The final reduction and fixation of the fractures was evaluated as anatomic in 17 dogs, near‐anatomic in 6 dogs, and nonanatomic in 1 dog.

Conclusions and Clinical Relevance— Application of the MRF is an effective technique for aiding the reduction of acetabular fractures in dogs. It maintains reduction while simultaneously permitting unimpeded access to the dorsal acetabular rim, thus facilitating accurate contouring of a plate. Accurate reduction and rigid fixation of articular fractures is essential to prevent secondary osteoarthritis.
Strangulating Obstruction Caused by Intestinal Herniation Through the Proximal Aspect of the Cecocolic Fold in 9 Horses
Authors: Gayle J'Mai M. , Macharg Margaret A. , Smallwood J. Edgar
Published: August 2002

Objective—To report the clinical and surgical findings and outcome for horses with strangulating obstruction caused by herniation through the proximal aspect of the cecocolic fold.

Study Design—Retrospective study.

Animals—Nine horses.

Methods—Medical records were reviewed for clinical signs, surgical findings and technique, and outcome. Cadaver ponies and necropsy specimens were also used to study the regional anatomy of the cecocolic fold.

Results—The ileum and distal jejunum were strangulated in 8 horses, whereas in 1 horse the small intestine and the left ascending colons were incarcerated in a rent in the cecocolic fold. Two horses were euthanatized at surgery, 6 horses had a small intestinal resection (mean length, 3 m; range, 1.5–6.4 m) and an end‐to‐side jejunocecostomy, and the entrapment was reduced without resection in the horse that had small intestine and ascending colon incarceration; cecocolic fold defects were not closed. One horse was euthanatized 36 hours after surgery because of endotoxemia. Six horses were discharged; 4 were available for long‐term follow‐up, of which 2 were euthanatized, and 2 were euthanatized 12 and 18 months after surgery because of colic signs. Variations in thickness of the cecocolic fold were observed in specimens obtained from necropsy of other horses and ponies.

Conclusions—Reasons for this defect are unknown, although observed anatomic differences in cecocolic fold thickness may contribute to the development of defects.

Clinical Relevance—Reduction of the entrapped bowel is easiest when traction is placed on the bowel at a 90° to the base of the cecum. Intestinal incarceration through rents within the proximal part of the cecocolic fold should be considered as a differential diagnosis for strangulating obstruction in horses.
Theory of hypernumbers and extrafunctions: Functional spaces and differentiation
Authors: Burgin Mark
Published: August 2002

The theory of hypernumbers and extrafunctions is a novel approach in functional analysis aimed at problems of mathematical and computational physics. The new technique allows operations with divergent integrals and series and makes it possible to distinct different kinds of convergence and divergence. Although, it resembles nonstandard analysis, there are several distinctions between these theories. For example, while nonstandard analysis changes spaces of real and complex numbers by injecting into them infinitely small numbers and other nonstandard entities, the theory of extrafunctions does not change the inner structure of spaces of real and complex numbers, but adds to them infinitely big and oscillating numbers as external objects. In this paper, we consider a simplified version of hypernumbers, but a more general version of extrafunctions and their extraderivatives in comparison with previous works.
Automatic Recognition of Muscle‐Invasive T‐Lymphocytes Expressing Dipeptidyl‐Peptidase IV (CD26) and Analysis of the Associated Cell Surface Phenotypes
Authors: Schubert W. , Friedenberger M. , Haars R. , Bode M. , Philipsen L. , Nattkemper T. , Ritter H.
Published: August 2002

A neural cell detection system (NCDS) for the automatic quantitation of fluorescent lymphocytes in tissue sections was used to analyze CD26 expression in muscle‐invasive T‐cells. CD26 is a cell surface dipeptidyl‐peptidase IV (DPP IV) involved in co‐stimulatory activation of T‐cells and also in adhesive events. The NCDS system acquires visual knowledge from a set of training cell image patches selected by a user. The trained system evaluates an image in 2 min calculating (i) the number, (ii) the positions and (iii) the phenotypes of the fluorescent cells. In the present study we have used the NCDS to identity DPP IV (CD26) expressing invasive lymphocytes in sarcoid myopathy and to analyze the associated cell surface phenotypes. We find highly unusual phenotypes characterized by differential combination of seven cell surface receptors usually involved in co‐stimulatory events in T‐lymphocytes. The data support a differential adhesive rather than a co‐stimulatory role of CD26 in muscle‐invasive cells. The adaptability of the NCDS algorithm to diverse types of cells should enable us to approach any invasion process, including invasion of malignant cells.
Modelling Tumor Progression, Heterogeneity, and Immune Competition
Authors: Ambrosi D. , Bellomo N. , Preziosi L.
Published: August 2002

This paper deals with the modeling of the immune response to the evolution of the progression of endothelial cells which have lost the differentiation and start their evolution towards metastatic states. The modeling is developed in the framework of the so‐called kinetic cellular theory. The model is critically analyzed on the basis of analytic solutions, asymptotic behaviors and numerical simulations that illustrate the scenarios predicted by the model. Finally, possible developments and generalizations that could describe other known phenomena are pointed out.
Marchuk′s Model of Immune System Dynamics with Application to Tumour Growth
Authors: Foryś Urszula
Published: August 2002

Marchuk′s model of a general immune reaction is presented in the paper. The results of investigation of the model are summarized. The qualitative behaviour of solutions to the model and its simplification is described. Many illustrations of recovery process, oscillations or lethal outcomes of a disease are shown. The model with time‐dependent immune reactivity is also considered. Periodic dynamics caused by different reasons are compared.

In the last section adaptation of the model to tumour–immune interactions is proposed. The role of interleukins in immune processes is taken into account to adapt Marchuk′s model to tumour growth dynamics. Possible immunotherapy is also considered in the proposed model. Some preliminary analysis of the model is presented.
The Single Row Routing Problem Revisited: A Solution Based on Genetic Algorithms
Authors: Zomaya Albert Y. , Karpin Roger , Olariu Stephan
Published: August 2002

With the advent of VLSI technology, circuits with more than one million transistors have been integrated onto a single chip. As the complexity of ICs grows, the time and money spent on designing the circuits become more important. A large, often dominant, part of the cost and time required to design an IC is consumed in the routing operation. The routing of carriers, such as in IC chips and printed circuit boards, is a classical problem in Computer Aided Design. With the complexity inherent in VLSI circuits, high performance routers are necessary. In this paper, a crucial step in the channel routing technique, the single row routing (SRR) problem, is considered. First, we discuss the relevance of SRR in the context of the general routing problem. Secondly, we show that heuristic algorithms are far from solving the general problem. Next, we introduce evolutionary computation, and, in particular, genetic algorithms (GAs) as a justifiable method in solving the SRR problem. Finally, an efficient O (nk) complexity technique based on GAs heuristic is obtained to solve the general SRR problem containing n nodes. Experimental results show that the algorithm is faster and can often generate better results than many of the leading heuristics proposed in the literature.
HIF‐1 and AP‐1 Cooperate to Increase Gene Expression in Hypoxia: Role of MAP Kinases
Authors: Michiels Carine , Minet Emmanuel , Michel Gaetan , Mottet Denis , Piret Jean‐Pascal , Raes Martine
Published: August 2002

HIF‐1 is the main transcription factor responsible for increased gene expression in hypoxia: VEGF, erythropoietin, GLUT‐1, and glycolytic enzymes are such target genes and all participate in the adaptative response of cells to hypoxia. AP‐1 activation by hypoxia has also been demonstrated in several cell lines and it cooperates with HIF‐1 for increasing VEGF gene transcription in hypoxia. Both HIF‐1 and AP‐1 activation by hypoxia seems to involve members of the MAP kinase family. Here, we summarize the data indicating that ERK and JNK are needed for activation of HIF‐1 and AP‐1, respectively.
Several Features of Tribochemical Synthesis Based on Aromatic Amines
Authors: Krasnov Alexander P , Kireev Vyacheslav V , Mit' Vera A , Kudasheva Dina S , Komarova Lidia I
Published: August 2002

The present work was devoted to the investigation of aromaticam in ereactions under the conditions of non-traditional tribochemical synthesis at room temperature in different triboreactors. Experimental data indicate the formation of reactive pre-polymer products of interaction, of low-molecular-weight non-melting and non-soluble pyromellitimide with bismaleimide, running the reaction of migratory copolymerization in the solid phase under the conditions in the vibromixer.

On the example of paraphenylenediamine and terephthalic aldehyde, the principal possibility of Schiff base synthesis has been demonstrated under the conditions in the shear micromixer, and the optimal regime has been determined. The obtained oligomer products contain thermostable fragments and reactive amino and aldehyde end-groups as well as double bonds of the maleimido cycle still remain. This composition allowed us to use them in polyheteroarylene synthesis of different structures in order to modify their properties.
Carbon-fibre-reinforced Composites of Epoxidized Novolac Resins
Authors: Patel M. B. , Patel R. H. , Patel V. S. , Patel R. G.
Published: August 2002

Epoxidized novolac cardanol (ENC) was prepared from cardanol-a component of cashew nut shell liquid. Various uniand bidirectional carbon-fibre-reinforced composites were fabricated using ENC and other novolac resins. Diaminodiphenyl methane was used as curing agent for the systems. The mechanical properties of the composites were determined.
Health and medical coverage in the UK national press
Authors: Entwistle Vikki , Hancock-Beaulieu Micheline
Published: August 2002

The growth of UK public interest in health in the last decade is reflected by the inclusion in most national newspapers of regular health or medical sections. These potentially allow subjects to be covered in detail, with more background information and useful advice. This paper reports on a content analysis study of eight national newspapers, which aimed to obtain an overview of press health coverage, to compare the coverage of popular and quality papers, and to analyse differences in health topic coverage between 1981 and 1990. The subject coverage, information provision and presentation of health related articles were considered. The most common subject categories were diseases, preventive medicine (including diet and exercise) and the National Health Service. Class inequalities in health received very little coverage. Clear differences were confirmed between quality broadsheet and popular tabloid newspapers. Quality papers provided more scientific information about health and paid more attention to political contexts. They made more use of authoritative journals and reports than popular papers, which focused on individual case histories and tended to quote a lay viewpoint. Popular press articles were generally more sensationalized and less objective in their reporting style. Newspapers do not exist solely to further public understanding, but have potential to contribute to it. Some informative, useful articles about health are found, but the study shows room for improvement, especially among the papers whose readership is concentrated in lower socio-economic groups.