bluuebunny/crossref_metadata_2025_split huggingface dataset:
Standardless analysis of small amounts of mineral samples by SR‐XRF and conventional XRF analyses
Authors: D'Angelo J. , Perino E. , Marchevsky E. , Riveros J. A. 
Published: November 2002

AbstractStandardless synchrotron radiation x‐ray fluorescence (SR‐XRF) and conventional XRF analytical results are presented. The method was applied to determine sample mass thickness. Concentrations of the major constituents of samples were also determined. Small samples (∼30 mg cm−2) were mounted on suitable substrates prepared with a mixture of chemicals. The intensity reduction of fluorescent lines emitted by substrates was analyzed. The choice of the substrate depends on the number of elements to be analyzed, since elemental concentrations are determined through the attenuation of substrate fluorescent lines. Comparative results obtained by using SR and conventional XRF are also presented. Although this method is used to characterize minerals, it may also be applied to several kinds of samples. Copyright © 2002 John Wiley & Sons, Ltd.
X‐ray fluorescence determination of major and minor elements in ferrotitanium, ferroniobium and ferrovanadium from compressed pellets and fusion beads
Authors: Coedo A. G. , Dorado T. , Padilla I. , Alguacil F. J. 
Published: November 2002

AbstractThis paper describes the x‐ray fluorescence determination of major and minor elements in ferrotitanium, ferroniobium and ferrovanadium. Samples preparation was accomplished using two different procedures: compressed pellets and fusion beads. Calibration graphs were prepared by mixing two ferroalloys of each of the considered types in different proportions. These ferroalloys were selected from industrial batches, providing the most varied composition available in order to cover as completely as possible the ranges of composition listed in ISO specifications. Total reproducibility tests, incorporating sample preparation and measurement, were performed using six samples prepared with the ferroalloys having the highest alloying grade. The relative standard deviation (RSD) values referred to the major element in Fe–Ti, Fe–Nb and Fe–V were 0.20, 0.17 and 0.21%, respectively, when using compressed pellets, and 0.16, 0.14 and 0.13% when using fusion beads. As regards the minor elements, the RSD values were in all cases below 5% for compressed pellets and below 3% for fused beads. The criterion applied to test the agreement of the two methods showed that the difference between the results provided by both samples preparation systems may be explained in terms of random errors. Accuracy was checked by analysing Certified Reference Materials of each of the types of ferroalloys studied. Copyright © 2002 John Wiley & Sons, Ltd.
Total electron yield of electrons emitted by x‐ray excitation from layered AlxGa1 − xAs–GaAs structures
Authors: Ebel Horst , Svagera Robert , Ebel Maria F. 
Published: November 2002

AbstractThin layers of AlxGa1 − xAs on GaAs substrates are characterized by thickness t and composition x. Measuring the GaK total electron yield (TEY) jumps delivers either x for known t or vice versa. A result of this investigation is the possibility of determining both quantities of a single layer structure by a systematic variation of the incidence angle of x‐radiation with regard to the specimen surface in the range 1–10°. Owing to the influence of the statistical significance of the measured data on the computed values of x and t, an x‐ray source with sufficient photon flux is an essential requirement. Possible applications are x‐values from 0 up to 0.5 and thicknesses from 0 up to 100 nm. Copyright © 2002 John Wiley & Sons, Ltd.
Analytical potential of EDXRF using toroidal focusing systems of highly oriented pyrolytic graphite (HOPG)
Authors: Kolmogorov Yuriy , Trounova Valentina 
Published: November 2002

AbstractTo solve a number of geochemical problems for ultrabasic and basic rocks, we applied the simplest and most accessible EDXRF method on an x‐ray tube with the use of toroidal double concave focusing systems and highly oriented pyrolytic graphite (HOPG). The results of measurements on clinopyroxene grains are shown. The weight of clinopyroxene grains was about 100 µm. Correlations of the element (Sr, Y, and Zr) concentrations in clinopyroxene grains determined by ICP‐MS and by EDXRF with a focusing HOPG monochromator and filter are shown. Copyright © 2002 John Wiley & Sons, Ltd.
Large volume hepatic freezing: association with significant release of the cytokines interleukin‐6 and tumor necrosis factor a in a rat model
Authors: Seifert Joachim K. , France Malcolm P. , Zhao Jing , Bolton Elaine J. , Finlay Ian , Junginger Theodor , Morris David L. 
Published: November 2002

AbstractAlthough cryotherapy of liver tumors is generally considered a safe procedure, a syndrome of coagulopathy and fatal multiorgan failure has been observed in some patients and is called the cryoshock phenomenon. Our aim was to establish an animal model of this phenomenon and examine the effects of the basic parameters of freezing or cryotherapy on it. A group of 75 female Sprague‐Dawley rats were allocated randomly to five groups: (1) sham laparotomy (n=15); (2) small (25% liver volume) single freeze (n=15); (3) small (25% liver volume) double freeze (n=15); (4) large (50% liver volume) single freeze (n=15); (5) large (50% liver volume) double freeze (n=15). Blood samples were collected at different postoperative times, and organs were harvested for histopathology. There was a significant release of tumor necrosis factor‐α (TNFα:) and interleukin 6 (IL‐6) following hepatic freezing, which was greatest in group 5. Postoperative serum cytokine levels were significantly associated with hepatocellular injury, as measured by postoperative serum aspartate transaminase (AST) concentrations. Severe hemoglobinuria and renal injury, as demonstrated by the serum creatinine level and the glomerular neutrophil count, were observed and were greatest in group 5. Hepatic cryosurgery is associated with release of IL‐6 and TNFα and renal injury in a rat model. It is likely that the cryoshock phenomenon is another form of the systemic inflammatory response syndrome. Based on the results of this study, it is possibly mediated by cytokines released from the frozen liver tissue. We therefore caution against cryothérapy of large tumor volumes.
Hepatic resection for colorectal metastases: Can preoperative scoring predict patient outcome?
Authors: Mala Tom , Bøhler Geir , Mathisen Øystein , Bergan Anstein , Søreide Odd 
Published: November 2002

AbstractA retrospective study was performed to define patient selection, safety, and efficacy of hepatic resection for colorectal metastases. The recently proposed preoperative clinical risk score (CRS) for selection of patients for surgery was also assessed. In all, 146 consecutive hepatic resections in 137 patients operated in the period between 1977 and 1999 were studied. Of these patients, 113 were classified into five CRS groups. Perioperative mortality was 1.4% (2 patients; no death in 120 patients operated after 1985) and morbidity was 38%. Five‐year actuarial survival (perioperative mortality included) was 29% (median 37 months), and actual 5‐year survival was 25% (17/69 patients). Patients operated after 1995 lived longer than those operated before 1995. Multiple regression analyses identified preoperative carcinoembryonic antigen CEA<100 µg/L, nodal status at resection of primary tumor, and RO vs. R1/R2 resection as prognostic parameters. CRS grouping had prognostic importance. The relative risk (hazard rate) of tumor recurrence in patients with CRS 3–4 was 2.1, compared to that of patients with CRS 0–2. Five‐year actuarial survival in the two groups was 12% and 40%, respectively. Fourteen of 15 long‐term survivors (τ;5 years) classified by the CRS system had CRS of 2 or less. Resection for colorectal liver metastases is safe, and long‐term survival rates are acceptable. CRS predicts patient outcome, but the clinical role in patient selection will have to be defined in prospective studies.
Effect of internal biliary drainage on plasma levels of endotoxin, cytokines, and C‐reactive protein in patients with obstructive jaundice
Authors: Padillo Francisco J. , Muntane Jordi , Montero Jose L. , Briceño Javier , Miño Gonzalo , Solorzano Guillermo , Sitges‐Serra Antonio , Pera‐Madrazo Carlos 
Published: November 2002

AbstractPreoperative biliary drainage may improve the cytokine and acute‐phase response derangements observed in patients with obstructive jaundice. We conducted a prospective longitudinal, before‐after trial in our 600‐bed teaching hospital. Twenty‐four patients with obstructive jaundice were investigated, 11 with benign obstruction and 13 with malignant disease. Endoscopic internal biliary drainage was performed in all patients (7 by papillotomy and 17 by endoprostheses). Endotoxin, tumor necrosis factor alpha (TNF‐α), interIeukin‐6 (IL‐6), nitric oxide production, and C‐reactive protein (CRP) were determined at admission and on days 2 and 7 after internal biliary drainage was accomplished. Bile cultures were obtained before and at the time of drainage. Endotoxin, IL‐6, TNF‐α, and CRP were significantly higher in patients with cancer. After internal drainage, endotoxin (11.4 vs. 2 EU/L; p<0.05), TNF‐α (87.5 vs. 48 pg/ml; p=0.03), and IL‐6 (324 vs. 232 pg/ml;/ p<0.05) plasma levels decreased significantly in the early postdrainage period in patients with cancer. Endotoxin, cytokines, as well as the CRP plasma values, however, increased again on day 7 after drainage. This trend was less marked in patients with benign obstruction. Patients with positive bile cultures after drainage displayed higher levels of CRP (115 vs. 62 mg/L; p=0.03), IL‐6 (598 vs. 330 pg/ml; p=0.04), and endotoxin (10.6 vs. 4.8 EU/L; p=0.02) than those with negative bile cultures. Biliary tract obstruction is associated with an increase in endotoxin levels, a positive acute‐phase response, and plasma cytokine elevation. After biliary drainage a transitory improvement of these alterations was observed, although values remained high 1 week postdrainage. These findings were associated with positive bile cultures.
Predictors of successful hepatic resection: Prognostic usefulness of hepatic asialoglycoprotein receptor analysis
Authors: Kokudo Norihiro , Vera David R. , Tada Keiichiro , Koizumi Mitsuru , Seki Makoto , Matsubara Toshiki , Ohta Hirotoshi , Yamaguchi Toshiharu , Takahashi Takashi , Nakajima Toshifusa , Muto Tetsuichiro 
Published: November 2002

AbstractTo test the clinical usefulness of hepatic asialogycoprotein receptor analysis in liver surgery, we have conducted univariate and multivariate analysis for the detection of cirrhotic patients and prediction of morbidity after hepatic resection. Liver scintigraphy using technetium 99m‐labeled asialoglycoprotein analog (TcGSA), ICG test, and CT hepatic volumetry were undertaken in 158 surgical patients including 111 who underwent hepatic resection. Hepatic functional parameters including Child‐Pugh score, indocyanine green retention at 15 minutes (ICG‐R15), clearance index (HH15), receptor index (LHL15), receptor concentration ([R]0), total hepatic receptor amount (R0) and hepatic parenchymal volume (HPV) were compared among patients with normal, cirrhotic, and non‐cirrhotic damaged liver. Preoperative hepatic functional parameters, resected parenchymal fraction (RPf), operative blood loss, and total receptor amount of the remnant liver (R0‐remnant) were compared between patients with and without signs of postoperative liver failure. All parameters but HPV were significantly different among patients with normal, cirrhotic, and noncirrhotic damaged liver. The multivariate analysis selected two significant (p<0.05) parameters, [R]0 and Child‐Pugh score for the detection of liver cirrhosis. Of the 111 patients who underwent resection, 14 developed transient signs of postoperative liver failure. Of the parameters tested, presence of liver cirrhosis, LHL15, R0, intraoperative blood loss, and R0‐remnant were significantly different between patients with and without signs of postoperative liver failure (p<0.05). The multivariate logistic regression analysis selected only R0‐remnant as a significant (p=0.022) parameter for the prediction of liver failure. The morbidity rate in patients with R0‐remnant under 0.05 µmoles was 100%, and the rate decreased in inverse proportion to R0‐remnant. in conclusion, combining the ASGP‐R concentration ([R]0) and the Child‐Pugh score best detected liver cirrhosis in surgical candidates. Cirrhotic patients and patients with a low R0‐remnant are at higher risk for postoperative liver failure. The present study confirms the usefulness of hepatic asialogycoprotein receptor analysis in liver surgery.
Influence of diabetes on persistent nonhealing ischemic foot ulcer in end‐stage renal disease
Authors: Yasuhara Hiroshi , Naka Shuji , Yanagie Hironobu , Nagawa Hirokazu 
Published: November 2002

AbstractThe aim of this study was to identify important atherosclerotic risk factors for characteristic nonhealing ischemic foot ulcers in patients with end‐stage renal failure. We retrospectively studied 534 consecutive hemodialysis patients in five dialysis units of the Tokyo metropolitan area between 1980 and 1999. The influence of risk factors for ischemic foot ulcers in hemodialysis patients was determined using a multivariate logistic model. The characteristic features were also evaluated with further comparison of the prevalence of risk factors between hemodialyzed diabetic patients with ischemic foot ulcers and another 61 age‐ and gender‐matched nonhemodialyzed diabetic patients with ischemic foot ulcers. In the logistic model, two factors emerged as important risk factors for ischemic foot ulcers: renal failure due to diabetes [odds ratio 21.580 (95% CI 4.838–96.251); p=0.0001] and a history of cerebrovascular disease [odds ratio 2.782 (1.015–7.624); p=0.0467]. On the basis of a comparison of age‐ and gender‐matched control patients, associated diabetic triopathy, a history of cerebrovascular disease, and hypertension were more frequent in the hemodialysis patients. The development of ischemic foot ulcers in those with end‐stage renal failure is strongly influenced by underlying advanced diabetic microangiopathy and such other factors as sequelae of cerebrovascular disease and patient debilitation.
Patient generated index: New instrument for measuring quality of life in patients with rectal cancer
Authors: Camilleri‐Brennan John , Ruta Danny A. , Steele Robert J. C. 
Published: November 2002

AbstractThe objective of this study was to assess the validity and responsiveness of a new quality of life instrument, the Patient Generated Index (PGI), in patients with rectal cancer. Thirty‐three patients with rectal cancer were administered the PGI, the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaires QLQ‐C30 and QLQ‐CR38, and the Medical Outcomes Study short form SF‐36 questionnaire preoperatively and at 3 months postoperatively. The PGI was assessed in this group of patients for validity and responsiveness. PGI scores achieved significant correlations with a number of domains on the three quality of life (QOL) questionnaires. Stepwise regression analysis showed that 91.3% of the variation in PGI scores could be explained by three health‐related QOL variables alone: pain, role limitations due to physical problems, and a global rating of health and QOL. The mean PGI score showed significant improvement 3 months following surgery. The PGI was found to be more responsive to change than the SF‐36, the QLQ‐C30, or the QLQ‐CR38 items except the micturition item. The PGI assesses the extent to which the expectations of patients suffering from rectal cancer are matched by reality; and it satisfies the criteria of validity and responsiveness of this instrument for this cancer. Further studies are needed to determine its psychometric properties in other areas of surgery and oncology. If these studies support our findings, we believe that patient‐centered measures such as the PGI may provide a meaningful assessment of the outcome of surgery for patients with cancer.
Predictive value of blood flow in the gastric tube in anastomotic insufficiency after thoracic esophagectomy
Authors: Miyazaki Tatsuya , Kuwano Hiroyuki , Kato Hiroyuki , Yoshikawa Minako , Ojima Hitoshi , Tsukada Katsuhiko 
Published: November 2002

AbstractAnastomotic insufficiency is considered to be one of the most serious complications associated with esophageal reconstruction. The purposes of this study were to identify (1) the relationship between anastomotic insufficiency and tissue blood flow (TBF) in the gastric tube in the perioperative period, and (2) the effects of intravenous prostaglandin E1 (PGE1) on TBF in the gastric tube. The study group consisted of 44 patients who were to undergo esophagectomy for esophageal cancer. Intraoperative and postoperative TBF on the serosal side of the gastric tube were measured by laser‐Doppler tissue blood flowmetry. The TBF of the Leakage(+) group (n=5) was poorer than that of the Leakage(−) group (n=39) during the intraoperative and postoperative periods. There was a significant difference in TBF between the two groups at postoperative day (POD) 3. There was a tendency in the PGE1(+) group (n=18) to exhibit richer blood flow through the anastomosis than the PGE1(−) group (n=26), intraoperatively, but the difference was not significant. Two of five Leakage(+) cases were also in the PGE11(+) group. There was no relationship between intraoperative medication with PGE1 and incidence of leakage. The TBF of three‐field lymph node dissection and reconstruction of the retrosternal route group (n=21) was poorer than that of the two‐field lymph‐node dissection and reconstruction of the posterior mediastinal route group (n=23). The TBF in the gastric tube after esophagectomy may be a predictor of anastomotic insufficiency. However, PGE1 treatment in the intraoperative period alone is not effective in preventing anastomotic insufficiency.
Sentinel node biopsy in early breast cancer in Taiwan
Authors: Yu Jvh‐Cherng , Hsu Giu ‐Cheng , Liu Yao ‐Chi , Sheu Lai ‐Fa , Li Su ‐Hui , Chao Tsu ‐Yi 
Published: November 2002

AbstractThe purpose of this study is to report the results of sentinel node (SN) biopsy for assessment of early breast cancer in Taiwan and to compare our results with those in other Asian countries and worldwide. We used methylene blue dye to identify SN in patients with clinically non‐palpable breast mass and palpable breast mass smaller than 3 cm. We also explored the role of imprint cytology and immunochemical studies to identify metastatic cancer cells in the lymph nodes. A total of 221 procedures on 218 patients were performed by a single surgeon. The SN was identified in 85.5% of the cases. The overall accuracy of identifying tumors in SN was 97.4%, with a sensitivity of 90.9%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 96.4%. The use of immunochemical techniques helped to identify micrometasta‐sis in SN or non‐SN. Our results on SN biopsy with the dye method were similar to those reported from Japan and elsewhere. We concluded that sentinel node biopsy, together with the use of immunochemical techniques to identify micrometastatic foci, has allowed surgeons to decide at the time of surgery whether to perform axillary node dissection.
Surface modification of W-Ti coatings induced by TEA
CO2 laser beam
Authors: PETROVIĆ SUZANA , GAKOVIĆ B. , TRTICA M. , NENADOVIĆ T. 
Published: November 2002

In this work, the interaction of a transversely excited
atmospheric (TEA) CO2 laser with tungsten–titanium
(W-Ti) alloy deposited on austenitic stainless steel is considered.
The W-Ti alloy as a refractory material possesses very good
physicochemical characteristics such as thermochemical stability
and high melting temperature. Studying of interactions of different
energetic particles or laser beams with W-Ti coatings has both
application and fundamental importance.The morphological features of the W-Ti coating, deposited on
austenitic stainless steel AISI 316, induced by a TEA
CO2 laser after multipulse cumulative laser action,
have been considered. The laser pulses with tail (FWHM = 120
ns, tail = 2 μs) and free-tail pulses (FWHM = 80 ns) have
been employed. Laser pulses used in the experiment had equal
peak power density I = 120 MWcm−2.
For the given peak power density, excessive surface changes
on the coating were registered. From direct observation on a
microscopic scale (OM, SEM), it can be concluded that W-Ti coatings
show different behavior under laser irradiation with various
temporal pulse shapes.
ON PARALLEL QUEUING WITH RANDOM SERVER CONNECTIVITY AND ROUTING
CONSTRAINTS
Authors: Bambos Nicholas , Michailidis George 
Published: November 2002

We study systems of parallel queues with finite buffers, a
single server with random connectivity to each queue,
and arriving job flows with random or class-dependent
accessibility to the queues. Only currently connected queues
may receive (preemptive) service at any given time, whereas
an arriving job can only join one of its accessible queues.
Using the coupling method, we study three key models,
progressively building from simpler to more complicated structures.In the first model, there are only random server connectivities.
It is shown that allocating the server to the Connected queue
with the Fewest Empty Spaces (C-FES) stochastically minimizes
the number of lost jobs due to buffer overflows, under conditions
of independence and symmetry.In the second model, we additionally consider random accessibility
of queues by arriving jobs. It is shown that allocating the
server to the C-FES and routing each arriving job to the currently
Accessible queue with the Most Empty Spaces (C-FES/A-MES) minimizes
the loss flow stochastically, under similar assumptions.In the third model (addressing a target application), we consider
multiple classes of arriving job flows, each allowed
access to a deterministic subset of the queues. Under analogous
assumptions, it is again shown that the C-FES/A-MES policy
minimizes the loss flow stochastically.The random connectivity/accessibility aspect enhances
significantly the structure and application scope of the classical
parallel queuing model. On the other hand, it introduces essential
additional dynamics and considerable complications. It is
interesting that a simple policy like FES/MES, known to be optimal
for the classical model, extends to the C-FES/A-MES in our case.
OPTIMAL CONTROL OF A TWO-STAGE TANDEM QUEUING SYSTEM WITH
FLEXIBLE SERVERS
Authors: Ahn Hyun-soo , Duenyas Izak , Lewis Mark E. 
Published: November 2002

We consider the optimal control of two parallel servers in
a two-stage tandem queuing system with two flexible servers.
New jobs arrive at station 1, after which a series of two
operations must be performed before they leave the system. Holding
costs are incurred at rate h1 per unit time
for each job at station 1 and at rate h2 per
unit time for each job at station 2.The system is considered under two scenarios; the collaborative
case and the noncollaborative case. In the prior, the servers
can collaborate to work on the same job, whereas in the latter,
each server can work on a unique job although they can work
on separate jobs at the same station. We provide simple conditions
under which it is optimal to allocate both servers to station
1 or 2 in the collaborative case. In the noncollaborative case,
we show that the same condition as in the collaborative case
guarantees the existence of an optimal policy that is exhaustive
at station 1. However, the condition for exhaustive service
at station 2 to be optimal does not carry over. This case is
examined via a numerical study.