bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the dependence structure and bounds of correlated parallel queues and their applications to synchronized stochastic systems
Authors: Li Haijun , Xu Susan H. 
Published: October 2002

This paper studies the dependence structure and bounds of several basic prototypical parallel queueing systems with correlated arrival processes to different queues. The marked feature of our systems is that each queue viewed alone is a standard single-server queuing system extensively studied in the literature, but those queues are statistically dependent due to correlated arrival streams. The major difficulty in analysing those systems is that the presence of correlation makes the explicit computation of a joint performance measure either intractable or computationally intensive. In addition, it is not well understood how and in what sense arrival correlation will improve or deteriorate a system performance measure.The objective of this paper is to provide a better understanding of the dependence structure of correlated queueing systems and to derive computable bounds for the statistics of a joint performance measure. In this paper, we obtain conditions on arrival processes under which a performance measure in two systems can be compared, in the sense of orthant and supermodular orders, among different queues and over different arrival times. Such strong comparison results enable us to study both spatial dependence (dependence among different queues) and temporal dependence (dependence over different time instances) for a joint performance measure. Further, we derive a variety of upper and lower bounds for the statistics of a stationary joint performance measure. Finally, we apply our results to synchronized queueing systems, using the ideas combined from the theory of orthant and supermodular dependence orders and majorization with respect to weighted trees (Xu and Li (2000)). Our results reveal how a performance measure can be affected, favourably or adversely, by different types of dependencies.
Modulation of growth and radiochemosensitivity of human malignant glioma cells by acidosis
Authors: Reichert Manuela , Steinbach Joachim P. , Supra Petra , Weller Michael 
Published: October 2002

AbstractBACKGROUNDGlioblastoma commonly is characterized by hypoxia and acidosis and the histologic features of tissue necrosis and neovascularization. Current approaches of adjuvant radiochemotherapy for patients with glioblastoma have only a modest impact on the natural course of this disease.METHODSThe authors examined the effects of acidosis on growth and response to irradiation and chemotherapy in cultured human malignant glioma cells.RESULTSThe authors found that mild acidosis (pH 7.0) inhibited the growth of cell lines that retained wild type p53 activity but did not inhibit the growth of cell lines that were devoid of p53 function. Transfer of a dominant‐negative p53 gene into p53 wild type cells failed to override the acidosis‐conferred growth arrest, suggesting that loss of p53 activity per se does not mediate escape from acidosis‐induced growth inhibition. Moderate acidosis (pH 6.6) inhibited the growth of all cell lines. Acidosis‐mediated growth arrest was not associated with a specific type of cell cycle arrest, e.g., in G0/G1 or G2/M phase. Acidosis did not result in consistent changes in radiosensitivity; however, it enhanced the cytotoxic effects of lomustine but conferred protection from topotecan, vincristine, teniposide, and cisplatin cytotoxicity. Lomustine exhibited enhanced stability at low pH, providing a putative mechanism for the enhanced cytotoxic effects of lomustine in acidotic conditions. Decreased sensitivity to the other drugs did not result from altered multidrug resistance drug transport activity.CONCLUSIONSTaken together, the current results suggest that tissue acidosis may be an important determinant of glioma cell responses to adjuvant radiochemotherapy. The superior activity of nitrosoureas, such as lomustine, compared with other agents in patients with glioblastoma may result in part from prolonged drug stability in an acidotic microenvironment. Cancer 2002;95:1113–9. © 2002 American Cancer Society.DOI 10.1002/cncr.10767
Immunomodulatory effects of high‐dose and low‐dose interferon α2b in patients with high‐risk resected melanoma
Authors: Kirkwood John M. , Richards Thomas , Zarour Hassane M. , Sosman Jeffrey , Ernstoff Marc , Whiteside Theresa L. , Ibrahim Joseph , Blum Ronald , Wieand Samuel , Mascari Ruth 
Published: October 2002

AbstractBACKGROUNDThe clinical antitumor activity of recombinant interferon α2b (IFNα2b) has been well documented in patients with advanced and high‐risk melanoma; however, its mechanism of action remains conjectural. Trial E2690 evaluated the immunomodulatory effects of IFNα2b in vivo during treatment at high doses (the HDI arm; n = 51 patients) and at low doses (the LDI arm; n = 54 patients) in relation to standard observation (OBS; n = 43 patients).METHODSThis study evaluated peripheral blood lymphocytes (PBLs) for phenotypic markers and cytotoxic functions at 1 month, 3 months, and 12 months in the HDI arm, the LDI arm, and the OBS arm and examined correlations between changes observed in PBLs or in tumors with regard to treatment dosage and disease outcome. Tumor biopsy samples were studied for response to IFNα2b at a range of concentrations in vitro.RESULTSBaseline blood phenotypic and functional assays did not predict disease outcome; however, modulation of these immunologic assays by IFNα2b treatment was observed and was associated with IFNα2b dosage. Tumor cell class II major histocompatibility antigen expression (human leukocyte/lymphocyte antigen DR) and adhesion molecule expression (ICAM‐1) were modulated by exposure to IFNα2b in a dose dependent manner. Blood natural killer (NK) cell function, T‐cell function, and subset distribution were modulated early by patients in the HDI arm and later by patients in the LDI arm. None of the variables tested in these studies predicted recurrence free survival. The numbers of patients studied were smaller than may be needed to detect potentially clinically significant changes.CONCLUSIONSThese data demonstrate changes in immunologic parameters associated with IFNα2b treatment and dosage that may account for some of the differences in the clinical efficacy of this modality. The current results also suggest the need for further study of newer molecular intermediates of IFNα2b and T‐cell response to specific antigens of melanoma. Cancer 2002;95:1101–12. © 2002 American Cancer Society.DOI 10.1002/cncr.10775
Thirteen‐year, long‐term efficacy of interferon 2α and interleukin 2‐based home therapy in patients with advanced renal cell carcinoma
Authors: Atzpodien Jens , Hoffmann Reinhard , Franzke Marcus , Stief Christian , Wandert Thomas , Reitz Martina 
Published: October 2002

AbstractBACKGROUNDThe goal of the current report was to demonstrate the long‐term efficacy of outpatient subcutaneous (sc) interferon α (IFN‐α) and sc interleukin 2 (IL‐2)‐based combination regimens in patients with metastatic renal cell carcinoma.METHODSIn three consecutive clinical trials, 443 patients received combined sc IFN‐α and sc IL‐2 (n = 97 patients); combined sc IFN‐α, sc IL‐2, and intravenous (iv) 5‐fluorouracil (5‐FU) (n = 260 patients); or combined sc IFN‐α, sc IL‐2, and iv 5‐FU with oral 13cis‐retinoic acid (n = 86 patients).RESULTSThe median overall survival was 21+ months. The 2‐year, 5‐year, and 13‐year survival rates were calculated at 45.26%, 15.96%, and 8.96%, respectively. The median time to disease progression was 6 months. The 2‐year, 5‐year, and 13‐year progression free survival rates were 17.84%, 9.54%, and 9.20%, respectively.CONCLUSIONSThe current data suggest that combined outpatient sc IFN‐α and sc IL‐2, according to the Atzpodien regimen, achieves long‐term survival benefits in a subset of patients with metastatic renal cell carcinoma, both with and without 13‐cis‐retinoic acid and/or 5‐fluorouracil. Cancer 2002;95:1045–50. © 2002 American Cancer Society.DOI 10.1002/cncr.10783
Role of ultrasound‐guided fine‐needle aspiration of indeterminate and suspicious axillary lymph nodes in the initial staging of breast carcinoma
Authors: Krishnamurthy Savitri , Sneige Nour , Bedi Deepak G. , Edieken Beth S. , Fornage Bruno D. , Kuerer Henry M. , Singletary S. Eva , Hunt Kelly K. 
Published: October 2002

AbstractBACKGROUNDUltrasound (US) is more sensitive than physical examination alone in determining axillary lymph node involvement during preliminary staging of breast carcinoma. Due to occasional overlap of sonographic features of benign and indeterminate lymph nodes, fine‐needle aspiration (FNA) of sonographically indeterminate/suspicious lymph nodes can provide a more definitive diagnosis than US alone. This study was undertaken to determine the diagnostic accuracy of US‐guided FNA of indeterminate/suspicious/metastatic‐appearing axillary lymph nodes during the initial staging of breast carcinoma.METHODSThe cytology of 103 cases of US‐guided FNA of nonpalpable indeterminate/suspicious/metastatic‐appearing lymph nodes was compared with the final histopathologic status of the entire axilla after axillary dissection. The final axillary lymph node status was categorized as either negative when all lymph nodes were negative for metastasis or positive when there was evidence of metastasis in one or more lymph nodes. The sensitivity, specificity, diagnostic accuracy, and false‐negative rate of US‐guided FNA of nonpalpable axillary lymph nodes in the preliminary staging process were calculated.RESULTSIn 51 of 103 cases (49.5%), the US‐guided FNA and histopathology were both positive for metastasis. In 24 of 103 cases (23.3%), both were negative. The apparent false‐positive FNA in 16 (15.5%) cases was explained by the complete response of the metastatic lymph nodes to neoadjuvant chemotherapy in the interval between FNA and axillary dissection. In 12 cases (11.6%), US‐guided FNA was negative, but metastasis was seen in histologic sections. All cases with three or more lymph nodes with metastatic disease and 93% of those with metastatic deposit measuring more than 0.5 mm were detected by US‐guided FNA. The probability of detecting lymph nodes with smaller metastatic deposit measuring less than 0.5 cm was 44%. The overall sensitivity of US‐guided FNA was 86.4%, the specificity was 100%, the diagnostic accuracy was 79.0%, the positive predictive value was 100%, and the negative predictive value was 67%.CONCLUSIONSUS‐guided FNA of nonpalpable indeterminate and suspicious axillary lymph nodes is a simple, minimally invasive, and reliable technique for the initial determination of axillary lymph node status in breast carcinoma. The common causes of discrepancy between the initial and final axillary lymph node status include failure to visualize all lymph nodes during US examination, small‐sized metastases, and preoperative neoadjuvant chemotherapy. Cancer 2002;95:982–8. © 2002 American Cancer Society.DOI 10.1002/cncr.10786
Salvage combination chemotherapy with 5‐fluorouracil and actinomycin D for patients with refractory, high‐risk gestational trophoblastic tumors
Authors: Matsui Hideo , Suzuka Kiyomi , Iitsuka Yoshinori , Yamazawa Koji , Tanaka Naotake , Mitsuhashi Akira , Seki Katsuyoshi , Sekiya Souei 
Published: October 2002

AbstractBACKGROUNDThe objective of this study was to evaluate the efficacy and toxicity of a high‐dose 5‐fluorouracil and actinomycin D regimen (the FA regimen) as salvage chemotherapy for patients with high‐risk gestational trophoblastic tumors (GTTs).METHODSFrom 1985 to 1997, 10 patients with refractory, high‐risk GTTs were treated with the FA regimen at Chiba University Hospital. Of those 10 patients, 7 patients developed drug resistance to methotrexate, etoposide, and actinomycin D combination chemotherapy (the MEA regimen); 1 patient developed recurrent disease after receiving the MEA regimen; and 2 patients developed recurrent disease after receiving combination chemotherapy with etoposide, methotrexate, and actinomycin D alternating with cyclophosphamide and vincristine (the EMA/CO regimen). The hematologic toxicity of the FA regimen was graded at every chemotherapy course.RESULTSWith the FA regimen, the survival rate was 80.0% (8 of 10 patients) for a mean follow‐up of 10 years. Two patients died due to multidrug resistance, and two patients subsequently developed recurrent disease. The two patients with recurrent disease were successfully salvaged again with the MEA regimen. The toxicity of the FA regimen was evaluated in 78 cycles. Myelosuppression seemed to be the dose‐limiting toxicity, and the incidences of World Health Organization Grade 4 leukocytopenia and thrombocytopenia were 6.4% and 3.8%, respectively, of 78 cycles.CONCLUSIONSAlthough etoposide‐containing chemotherapy is currently the most effective and well‐tolerated regimen for patients with high‐risk GTTs, 20–30% of patients develop resistance to etoposide‐containing regimens. Salvage combination chemotherapy with FA is effective for these patients with refractory disease, and the toxicity is predictable and manageable. Cancer 2002;95:1051–4. © 2002 American Cancer Society.DOI 10.1002/cncr.10790
Outbreak of jaundice and hemorrhagic fever in the Southeast of Brazil in 2001: Detection and molecular characterization of yellow fever virus
Authors: de Filippis A.M.B. , Nogueira R.M.R. , Schatzmayr H.G. , Tavares D.S. , Jabor A.V. , Diniz S.C.M. , Oliveira J.C. , Moreira E. , Miagostovich M.P. , Costa E.V. , Galler R. 
Published: October 2002

AbstractBetween January and March 2001, an outbreak of jaundice and hemorrhagic fever occurred in the state of Minas Gerais, Southeast region of Brazil, in which a mortality rate of 53% was reported. Seroconversion, virus isolation, histopathological and immunohistochemical findings, and reverse transcription‐polymerase chain reaction (RT‐PCR) identified yellow fever virus (YFV) as the etiological agent responsible for the outbreak. Partial nucleotide sequence analysis from a fragment of the YFV genome spanning parts of nonstructural (NS) 5 gene and 3′ noncoding region (3′ UTR) showed that the YFV involved in this outbreak belongs to South American genotype I and differs from the Brazilian virus identified in 1996. J. Med. Virol. 68:620–627, 2002. © 2002 Wiley‐Liss, Inc.
Genetic diversity of echovirus 30 during a meningitis outbreak, demonstrated by direct molecular typing from cerebrospinal fluid
Authors: Bailly Jean‐Luc , Brosson Damien , Archimbaud Christine , Chambon Martine , Henquell Cécile , Peigue‐Lafeuille Hélène 
Published: October 2002

AbstractEchovirus 30 is one of the enterovirus serotypes isolated most frequently in meningitis cases. The genetic diversity of echovirus 30 was investigated in patients hospitalised during an outbreak in 2000 in Clermont‐Ferrand, France. A nested reverse transcription‐PCR (RT‐PCR) assay was developed for qualitative analysis of the echovirus 30 VP1 encoding sequence directly from cerebrospinal fluid. The viral sequences obtained for 22 patients were compared with those of virus isolates obtained from nine patients with echovirus 30 meningitis admitted to hospital in 1996–1997 and with echovirus 30 sequences from international databases. In 2000, meningitis cases were caused by two virus variants (C3 and C4) distinct genetically from the other two variants (C1 and C2) identified during the period 1996–1997. A detailed phylogenetic analysis established that the C1, C2, and C3 variants had close relatives among viruses previously identified in other geographical areas. The C4 variant had not been described earlier. The genomic differences observed between the four echovirus 30 variants arose at synonymous sites indicating that the viruses shared similar antigenic sites in the VP1 encoding sequence. Overall, these observations suggest wide circulation of different echovirus 30 variants and periodic importation of new viruses. The apparent displacement observed between virus variants did not result from a selective advantage caused by antigenic variation. J. Med. Virol. 68:558–567, 2002. © 2002 Wiley‐Liss, Inc.
Convergence of finite element approximations of large eddy motion
Authors: Iliescu Traian , John Volker , Layton William J. 
Published: October 2002

AbstractFluid motion in many applications occurs at higher Reynolds numbers. In these applications dealing with turbulent flow is thus inescapable. One promising approach to the simulation of the motion of the large structures in turbulent flow is large eddy simulation in which equations describing the motion of local spatial averages of the fluid velocity are solved numerically. This report considers “numerical errors” in LES. Specifically, for one family of space filtered flow models, we show convergence of the finite element approximation of the model and give an estimate of the error. © 2002 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 18: 689–710, 2002; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/num.10027.
On the finite‐differences schemes for the numerical solution of two dimensional Schrödinger equation
Authors: Subaşi Murat 
Published: October 2002

AbstractIn this study three different finite‐differences schemes are presented for numerical solution of two‐dimensional Schrödinger equation. The finite difference schemes developed for this purpose are based on the (1, 5) fully explicit scheme, and the (5, 5) Noye‐Hayman fully implicit technique, and the (3, 3) Peaceman and Rachford alternating direction implicit (ADI) formula. These schemes are second order accurate. The results of numerical experiments are presented, and CPU times needed for this problem are reported. © 2002 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 18: 752–758, 2002; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/num.10029.
On the subdomain‐Galerkin/least squares method for 2‐ and 3‐D mixed elliptic problems with reaction terms
Authors: Yang Suh‐Yuh 
Published: October 2002

AbstractIn this article we apply the subdomain‐Galerkin/least squares method, which is first proposed by Chang and Gunzburger for first‐order elliptic systems without reaction terms in the plane, to solve second‐order non‐selfadjoint elliptic problems in two‐ and three‐dimensional bounded domains with triangular or tetrahedral regular triangulations. This method can be viewed as a combination of a direct cell vertex finite volume discretization step and an algebraic least‐squares minimization step in which the pressure is approximated by piecewise linear elements and the flux by the lowest order Raviart‐Thomas space. This combined approach has the advantages of both finite volume and least‐squares methods. Among other things, the combined method is not subject to the Ladyzhenskaya‐Babus̆ka‐Brezzi condition, and the resulting linear system is symmetric and positive definite. An optimal error estimate in the H1(Ω) × H(div; Ω) norm is derived. An equivalent residual‐type a posteriori error estimator is also given. © 2002 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 18: 738–751, 2002; Published online in Wiley InterScience (www.interscience.wiley.com); DOI 10.1002/num.10030.
Teachers implementing writing‐to‐learn strategies in junior secondary science: A case study
Authors: Hand Brian , Prain Vaughan 
Published: October 2002

AbstractAlthough there is now strong support for the use of writing‐to‐learn in science, research in this field has tended to ignore the challenges facing teachers in developing new understandings and practices in relation to this use of writing. This paper reports on a 4‐year study examining teachers' concerns in implementing writing‐to‐learn strategies within science classrooms based on using a model of writing‐to‐learn. The study reports in detail on two teachers' participation in an ongoing in‐service program to develop pedagogical practices to support writing‐to‐learn strategies. The three central issues for the two teachers were assessment, planning and setup, and their changing roles as classroom teachers. © 2002 Wiley Periodicals, Inc.Sci Ed86:737–755, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/sce.10016
A study of MRP benefits and costs
Authors: Schroeder Roger G. , Anderson John C. , Tupy Sharon E. , White Edna M. 
Published: October 2002

AbstractThis paper describes benefits and costs of MRP systems based on a large survey of MRP users. These users report they have achieved significant improvements in inventory turnover, delivery performance, and other benefits, and that further improvements are expected when their MRP systems are fully implemented. A series of regression models are also described in the paper which explain why some companies achieve more benefits from MRP than others. The models are not only fitted to the sample data, but they obtain good predictive results on a holdout sample. These models indicate that companies should stress a broad approach to implementation; there is no one overriding factor which guarantees MRP success.
The implementation of computer based systems
Authors: Meredith Jack R. 
Published: October 2002

AbstractThe difficulty of implementing planned change in an organization is legend. In the last 20 years the implementation of computer based models and systems in particular has received a significant amount of attention in the form of hundreds of conference presentations, published case studies, and research reports. Yet, system implementation failures are still prevalent. p]This paper surveys the implementation literature primarily in three fields: management information systems, operations research/management science, and production‐inventory management. Common difficulties are identified and managerial proverbs, consultants' insights, statistically verified procedures, research conclusions. and other such documented wisdom for improving the chances of implementation are analyzed. p]A classification scheme is developed which divides this documented material into three diverse categories of pitfalls in implementation. These categories are then discussed from the perspective of providing managers with the information needed to analyze their own organization in terms of the likelihood of successfully implementing such computer based information systems as Material Requirements Planning (MRP).
Static vs. dynamic priority rules for check processing in multiple dispatch‐multiple branch banking
Authors: Mabert Vincent A. 
Published: October 2002

AbstractThis paper presents a study comparing the use of four static and two dynamic priority rules for sequencing bundled checks in the check clearing operations in a bank's back office. The six priority rules are tested in a controlled computer simulation experiment, where bank factors of check bundle size, check bundle value, transit deadlines (dispatches), and destination proportions are systematically varied over prescribed levels. The results indicate that priority rule performance, measured by reduced float, is significantly affected by bank factors. The test results indicate that the two dynamic priority rules performed statistically better than three of the four static rules tested.The study reported here should prove useful to bank operation managers. The sequencing rules investigated here influence the level of float for a bank faced with multiple dispatches during the day. The test environments duplicated a variety of operating conditions that can be present in commercial banks. Therefore, the robustness of the tested static and dynamic rules were observed in reducing float under different conditions. Dynamic rules require recomputing priorities to reflect changes in time and create greater implementation effort to use effectively. Static rules require only one priority computation, resulting in easier implementation. This study indicates that one of the static priority rules tested provides comparable performance to the two dynamic rules.