bluuebunny/crossref_metadata_2025_split huggingface dataset:
African‐American/White differences in breast carcinoma
Authors: Jones Beth A. , Kasl Stanislav V. , Howe Christine L. , Lachman Mary , Dubrow Robert , Curnen Mary McCrea , Soler‐Vila Hosanna , Beeghly Alicia , Duan Fenghai , Owens Patricia 
Published: August 2004

AbstractBACKGROUNDDespite mounting evidence that breast tumors in African‐American (AA) women are more aggressive compared with breast tumors in white (W) women, little is known regarding racial/ethnic differences in genetic alterations that may be of prognostic importance.METHODSIn this population‐based cohort of 322 AA women (45%) and W women (55%) who were diagnosed with breast carcinoma between 1987–1989, the authors evaluated available archived tumor tissue (n = 247 samples) for racial differences in selected genetic alterations and other prognostic indicators. Tumor characteristics were assessed by immunohistochemistry and/or expert review.RESULTSAlterations in p53 were significantly more common in AA women compared with W women (odds ratio, 4.00; 95% confidence interval, 1.77–9.01) and remained statistically significant in models that were adjusted for disease stage at diagnosis, according to American Joint Committee on Cancer (AJCC) criteria, and for other prognostic indicators. No racial difference with regard to HER‐2/neu status was observed, but alterations in c‐met were more common in AA women once the model was adjusted for negative confounders (not significant). Among other tumor characteristics, significant findings included later AJCC stage and higher histologic and nuclear grade tumors in AA women. In addition, the burden of aggressive tumor characteristics was greater in AA women because they were more likely to be at high risk on multiple factors (e.g., both high histologic grade and high nuclear grade [P = 0.03] and negative status for both estrogen receptors and progesterone receptors [P = 0.01]).CONCLUSIONSData from this population‐based cohort confirmed that breast tumors in AA women most likely are more aggressive compared with breast tumors in W women and offer new evidence for possible racial/ethnic differences with regard to p53 alterations. Cancer 2004. © 2004 American Cancer Society.
Breast carcinoma in African‐American and White women
Authors: Newman Lisa A. 
Published: August 2004

The door to improved understanding of ethnicity‐related variations in breast carcinoma risk and outcome has now been wedged open by the powerful tools of molecular biology. It is the responsibility of clinicians and investigators to accept the challenge of conducting the studies, collecting and interpreting the data, and validating the results.See also pages 1293–301.
Intramammary lymph node metastases are an independent predictor of poor outcome in patients with breast carcinoma
Authors: Shen Jeannie , Hunt Kelly K. , Mirza Nadeem Q. , Krishnamurthy Savitri , Singletary S. Eva , Kuerer Henry M. , Meric‐Bernstam Funda , Feig Barry , Ross Merrick I. , Ames Frederick C. , Babiera Gildy V. 
Published: August 2004

AbstractBACKGROUNDBreast carcinoma with intramammary lymph node (intraMLN) metastases is considered to be Stage II disease, even in the absence of axillary lymph node involvement. Nonetheless, little is known regarding the clinical significance of intraMLN metastases. The goals of the current retrospective analysis were to elucidate the clinical relevance of intraMLN metastases and to assess the relation between such metastases and outcome in patients with breast carcinoma.METHODSOne hundred ninety‐six intraMLN specimens obtained between 1983 and 2003 were identified in the pathology database at The University of Texas M. D. Anderson Cancer Center (Houston, TX); 130 of these specimens were obtained in association with a primary breast malignancy. Data on the clinical and pathologic features of these specimens were collected and evaluated on univariate and multivariate analysis for potential correlations with 5‐year rates of disease‐free survival (DFS), disease‐specific survival (DSS), and overall survival (OS). The median follow‐up duration was 36 months (range, 12–180 months).RESULTSThe median age of the 130 patients in the current study was 53 years (range, 27–84 years). Twenty‐four patients (18%) had intraMLNs that were identified preoperatively by either mammographic or sonographic methods; in the remaining 106 cases, intraMLNs were detected on pathologic examination of surgical breast specimens. IntraMLN metastases were found in 28% of all cases (n = 36). Most patients who had intraMLN metastases (81%) also had axillary metastases; however, isolated intraMLN metastases were documented in 6 patients (5%). Univariate analysis revealed that patients with intraMLN metastases (compared with all other patients) had poorer 5‐year rates of DFS (54% vs. 89%; P = 0.001), DSS (66% vs. 90%; P = 0.001), and OS (64% vs. 88%; P = 0.004). Furthermore, multivariate analysis indicated that intraMLN involvement was an independent predictor of reduced DFS (hazard ratio, 2.33; P = 0.03), DSS (hazard ratio, 5.32; P = 0.002), and OS (hazard ratio, 3.22; P = 0.006).CONCLUSIONSThe current retrospective analysis demonstrated that the presence of intraMLN metastases is an independent predictor of poor outcome in patients with breast carcinoma. Identification of an intraMLN on preoperative imaging should prompt further histopathologic assessment. Identification of malignant intraMLNs by lymphatic mapping may help to identify high‐risk patients for whom further evaluation of the axillary lymph nodes is warranted despite otherwise clinically negative findings in the axilla. Cancer 2004. Published 2004 American Cancer Society.
Adjuvant postoperative radiotherapy for colon carcinoma
Authors: Mendenhall William M. , Amos E. Henry , Rout W. Robert , Zlotecki Robert A. , Hochwald Steven N. , Cance William G. 
Published: August 2004

AbstractBACKGROUNDThe objective of this report was to review the role of adjuvant postoperative radiotherapy (RT) for patients with adenocarcinoma of the colon.METHODSThe authors reviewed the pertinent literature.RESULTSData suggested that locoregional postoperative RT improves both local control and survival for patients with T4N0–N1 tumors. There also may be a benefit for patients with T3N1–N2 tumors, but the data were equivocal. Whole abdominal RT may result in a similar benefit but is associated with increased toxicity.CONCLUSIONSPostoperative RT should be considered for patients with T4N0–N1 colon carcinoma. Locoregional fields should be used. Cancer 2004. © 2004 American Cancer Society.
Access‐controlled resource discovery in pervasive networks
Authors: Raman Sanjay , Clarke Dwaine , Burnside Matt , Devadas Srinivas , Rivest Ronald 
Published: August 2004

AbstractNetworks of the future will be characterized by a variety of computational devices that display a level of dynamism not seen in traditional wired networks. Because of the dynamic nature of these networks, resource discovery is one of the fundamental problems that must be solved. While resource discovery systems are not a novel concept, securing these systems in an efficient and scalable way is challenging. This paper describes the design and implementation of an architecture for access‐controlled resource discovery. This system achieves this goal by integrating access control with the Intentional Naming System (INS), a resource discovery and service location system. The integration is scalable, efficient, and fits well within a proxy‐based security framework designed for dynamic networks. We provide performance experiments that show how our solution outperforms existing schemes. The result is a system that provides secure, access‐controlled resource discovery that can scale to large numbers of resources and users. Copyright © 2004 John Wiley & Sons, Ltd.
A role‐based infrastructure management system: design and implementation
Authors: Shin Dongwan , Ahn Gail‐Joon , Cho Sangrae , Jin Seunghun 
Published: August 2004

AbstractOver the last decade there has been a tremendous advance in the theory and practice of role‐based access control (RBAC). One of the most significant aspects of RBAC can be viewed from its management of permissions on the basis of roles rather than individual users. Consequently, it reduces administrative costs and potential errors. The management of roles in various RBAC implementations, however, tends to be conducted on an ad hoc basis, closely coupled with a certain context of system environments. This paper discusses the development of a system whose purpose is to help manage a valid set of roles with assigned users and permissions for role‐based authorization infrastructures. We have designed and implemented the system, called RolePartner. This system enables role administrators to build and configure various components of a RBAC model so as to embody organizational access control policies which can be separated from different enforcement mechanisms. Hence the system helps make it possible to lay a foundation for role‐based authorization infrastructures. Three methodological constituents are introduced for our purposes, together with the design and implementation issues. The system has a role‐centric view for easily managing constrained and hierarchical roles as well as assigned users and permissions. An LDAP‐accessible directory service was used for a role database. We show that the system can be seamlessly integrated with an existing privilege‐based authorization infrastructure. Copyright © 2004 John Wiley & Sons, Ltd.
Salicylic acid‐mediated potentiation of Hsp70 induction correlates with reduced apoptosis in tobacco protoplasts
Authors: Cronjé Marianne J. , Weir Iona E. , Bornman Liza 
Published: August 2004

AbstractBackgroundElevated temperatures jeopardize plant disease resistance, as mediated by salicylic acid (SA). SA potentiates heat‐induced expression of the 70‐kDa heat shock protein (Hsp70) in tomato cells. In mammalian cells, Hsp70 suppresses apoptosis. We hypothesized that potentiation of heat‐induced Hsp70 by SA contributes to a reduction in apoptosis in tobacco protoplasts.MethodsTobacco protoplasts (Nicotiana tabacum) were exposed to SA (70 μM) at normal temperatures or in combination with heat shock. Hsp70/Hsc70 accumulation and phosphatidylserine (PS) exposure, DNA fragmentation, as well as loss of mitochondrial membrane potential were quantified by flow cytometry.Results and ConclusionsSA at normal temperatures did not influence Hsp70/Hsc70 accumulation, but were found to induce apoptosis. In contrast, SA in combination with HS potentiated heat‐induced Hsp70/Hsc70 accumulation in tobacco protoplasts that correlated negatively with apoptosis, illustrated by decreased PS exposure and DNA fragmentation and enhanced mitochondrial membrane potential. We propose that this correlation supports a possible role for apoptosis suppression by Hsp70 under elevated temperatures during pathogen infection. © 2004 Wiley‐Liss, Inc.
Architectural analysis of oral cancer, dysplastic, and normal epithelia
Authors: Landini Gabriel , Othman Ibrahim E. 
Published: August 2004

AbstractBackgroundWe present a novel, automated, and quantitative approach to evaluate local epithelial tissue architecture based on mathematical graph theory.MethodsFour hundred forty‐one images of three diagnostic classes of oral epithelium (normal, dysplastic, and neoplastic) were analysed. The epithelial compartment was partitioned into exclusive areas associated with each nucleus to approach the theoretical cell extents. The spatial arrangement of cells in neighbourhoods of two sizes was characterised by constructing graph networks based on the cell centroids and recording 29 statistical properties. We analysed 104,627 and 67,590 neighbourhoods of diameters 37.5 and 75 μm, respectively.ResultsThe discrimination power of the architectural descriptors was evaluated by using discriminant analysis. The best neighbourhood discrimination rate was 75% for normal versus carcinoma. For the pooled data, discrimination into three classes based on largest number of neighbourhoods associated with each class was 100% correct. Case‐wise, discrimination rates were 67%, 100%, and 80% correct for normal, premalignant, and malignant. When considering two classes, discrimination rates was 89% (normal) and 100% (malignant) correct, with 71% of premalignant cases assigned to the malignant class.ConclusionsThe results indicate that unbiased and reproducible quantification of tissue architectural features is possible and may provide valuable morphological information for diagnostic purposes. © 2004 Wiley‐Liss, Inc.
QOS and call admission control of multimedia traffic in a PCS network
Authors: Lee Duan‐Shin , Chen Chun‐Chia 
Published: August 2004

AbstractIn this paper we study the quality of service of integrated voice and data services in a wireless network. The voice traffic is transmitted in circuit‐switched mode and data traffic is transmitted in packet‐switched mode. Voice traffic has high transmission priority and data packets are transmitted only when there are available channels not used by the voice traffic. Otherwise, the data packets wait in a data buffer. We consider two schemes to reduce the forced termination probability for the handoff voice calls. The two schemes are the reserved channel scheme and the queueing priority scheme. We apply a fluid analysis to study the performance of the data buffer under the two handoff schemes and the basic system in which there is no arrangement to reduce the forced termination probability of handoff calls. From this analysis, we derive admission controls for voice traffic as well as for data traffic. This analysis also enables us to conclude that the reserved channel scheme not only is more effective in reducing the forced termination probability of handoff calls, it is also more effective in providing the QOS guarantee for the data traffic. Another contribution of this paper is to develop a perturbation analysis to solve the fluid models efficiently and quickly. Copyright © 2004 John Wiley & Sons, Ltd.
The study of handoff prediction schemes for resource reservation in mobile multimedia wireless networks
Authors: Lu Li‐Liann , Wu Jean‐Lien C. , Chen Wei‐Yeh 
Published: August 2004

AbstractIn this paper, the mobility‐dependent predictive resource reservation (MDPRR) scheme is proposed to provide flexible usage of scarce resource in mobile multimedia wireless networks. An admission control scheme is also considered to further guarantee the QoS of real‐time traffic. The area of a cell is divided into non‐handoff, pre‐handoff, and handoff zones so that bandwidth is reserved in the target/sub‐target cell as mobile stations move into the pre‐handoff zone and leave the serving base station. The amount of bandwidth to be reserved is dynamically adjusted according to the location, the instantaneous variation of velocity and direction of mobile stations. Two scenarios of the MDPRR scheme are compared by considering the velocity threshold in the calculation of the weight of direction. A number of designs are investigated to further enhance the performance of the proposed scheme. The results show that employing the velocity threshold in the MDPRR scheme can indeed reduce connection dropping probability, and make better usage of the reserved bandwidth. Copyright © 2004 John Wiley & Sons, Ltd.
A multi‐service link layer architecture for the wireless Internet
Authors: Xylomenos George , Polyzos George C. 
Published: August 2004

AbstractThe performance of Internet applications over wireless links is disappointing due to the adverse effects of wireless errors on higher layer protocols and applications. This paper focuses on link layer enhancement mechanisms which attempt to hide these wireless impairments. We simulate file transfer and WWW browsing over TCP and continuous media distribution over UDP, in conjunction with various link layer schemes. Our results reveal that WWW browsing behaves differently than bulk file transfer, that some TCP aware enhancements have limited applicability and that UDP applications are best served by schemes inappropriate for TCP. We then describe a multi‐service link layer architecture that simultaneously enhances the performance of diverse applications by supporting multiple error recovery schemes in parallel. In order to evaluate our architecture, we repeat our previous simulations with all applications executing simultaneously. The results reveal that with our approach each application achieves similar improvements as when it operates alone over its preferred link layer. Copyright © 2004 John Wiley & Sons, Ltd.
Capacity optimizing channel allocation schemes for multi‐service cellular systems
Authors: Yang Ming , Chong Peter H. J. 
Published: August 2004

AbstractThe trend of the wireless communication system is to provide various types of services such as voice, data and video etc. Due to the limited radio resources with international agreement, how to achieve the optimum system capacity becomes a paramount issue. In this paper, we use the idea of channel partitioning (CP) employing different reuse factors to support multiple services that require different signal‐to‐interference ratios (SIRs) in cellular systems. Two types of services are considered in this paper. Thus, we use a large reuse factor to support high SIR required service while we use a small reuse factor to support low SIR required service. From the system point of view, the average reuse factor becomes smaller and the system capacity can be improved. The system performance of CP with fixed channel allocation (FCA) scheme, namely fixed channel partitioning (FCP), is first proposed and analysed using Markov chain in a single cell model. Then a dynamic channel allocation scheme with CP called dynamic channel partitioning with interference information (DCP‐WI) is proposed and studied in the multiple‐cell model by computer simulation. The analysis and simulation results show that our proposed schemes can improve the system capacity depending on the traffic load fraction for each service. For equal arrival rate for both services, FCP and DCP‐WI provide about 33 and 60% capacity improvement respectively over a conventional FCA system using a single reuse factor to support two types of services. Copyright © 2004 John Wiley & Sons, Ltd.
Token bank fair queuing: a new scheduling algorithm for wireless multimedia services
Authors: Wong William K. , Tang Helen Y. , Leung Victor C. M. 
Published: August 2004

AbstractThe token bank fair queuing algorithm (TBFQ) is a novel scheduling algorithm that is suitable for wireless multimedia services. The bandwidth allocation mechanism integrates the leaky bucket structure with priority handling to address the problem of providing quality‐of‐service (QoS) guarantees to heterogeneous applications in the next generation packet‐switched wireless networks. Scheduling algorithms are often tightly integrated with the wireless medium access control (MAC) protocol. However, when heterogeneous wireless systems need to be integrated and interoperate with each other, it is desirable from the QoS provisioning standpoint to decouple scheduling algorithm from the MAC protocol. In this paper we propose a framework of seamless QoS provisioning and the application of TBFQ for uplink and downlink scheduling in wireless networks. We study its performance under a generic medium access framework that enables the algorithm to be generalized to provide QoS guarantees under various medium access schemes. We give a brief analysis of the algorithm and compare its performance with common scheduling algorithms through simulation. Our results demonstrate that TBFQ significantly increases wireless channel utilization while maintaining the same QoS, unlike many fair queuing algorithms, TBFQ does not require time‐stamping information of each packet arrival—an impractical feature in an already resource scarce environment. This makes TBFQ suitable for wireless multimedia communication. Copyright © 2004 John Wiley & Sons, Ltd.
Fair scheduling for spectrally efficient multi‐service wireless data provisioning
Authors: Sunay M. Oǧuz , Ekşim Ali 
Published: August 2004

AbstractEfficient wireless packet data access is possible by exploiting multi‐user diversity. This is done by using an opportunistic multiple access system that allocates system resources to one user at a time while using adaptive modulation and coding. Based on this outcome, recently the IS‐856 system was developed. A scheduling algorithm provides resource allocation in the IS‐856 system, and its proper design is perhaps one of the most crucial aspects ensuring good system performance. We present a number of such algorithms in this paper, two of which are new, and provide a comparative performance evaluation. The proposed algorithms appear to have the best overall performance of achieving high system throughputs without diverging much from the optimal latency performance. We then show that the IS‐856 system can easily be adjusted to provide a multitude of services, each with different QoS requirements. Extensive performance evaluations show that good system performance can be maintained in the multi‐service scenario. The paper also presents means of providing multicast service provisioning in the IS‐856 system. Copyright © 2004 John Wiley & Sons, Ltd.
Out‐of‐band polling scheme for QoS support in wireless LANs
Authors: Lim Teck Meng , Tantra Juki Wirawan , Foh Chuan Heng , Lee Bu Sung 
Published: August 2004

AbstractRecent researches in wireless local area networks (WLANs) have shown the challenges in providing an effective scheme to realize high throughput and transmission of real‐time traffic with a certain quality of service. This scheme must facilitate low worst‐case delay bounds and scale with the increase of data rate as technology advances. We introduce out‐of‐band polling scheme (OBPS), which separates the signalling for packet transmissions from the data channel; it uses an efficient polling method on a signalling channel for an access point to schedule packet transmissions with different priorities for upstream transmission. We also include a transmission sequences to efficiently schedule delivery of real‐time downstream packets. OBPS can adopt any packet scheduling algorithms to provide service differentiation. We choose deficit round robin scheduling algorithm for upstream and downstream traffic to provide rate differentiation and fairness. Through analytical and simulation results, we show that OBPS can achieve high throughput, provide rate differentiation and support bidirectional transmissions of real‐time packets. We derive upstream and downstream worst‐case delay bounds for OBPS, which serve as parameters for analysing scheduling algorithms that can be deployed to achieve a certain quality of service for real‐time packets. To illustrate that, we derive the worst‐case delay bounds of OBPS with DRR. Our delay bounds are realistic as it is based on upstream and downstream packet transmissions on a half‐duplex channel. We also show that OBPS is scalable for deployment in future high speed WLANs. Copyright © 2004 John Wiley & Sons, Ltd.