bluuebunny/crossref_metadata_2025 huggingface dataset:
A General Seifert–Van Kampen Theorem for Algebraic Fundamental Groups
Authors: Stix Jakob
Published: November 2007

A Seifert–Van Kampen theorem describes the fundamental group of a space in terms of the fundamental groups of the constituents of a covering and the conﬁguration of connected components of the covering. Here we provide the combinatorial part of such a theorem for the most general sort of coverings. Thus a Seifert–Van Kampen theorem is reduced to a purely geometric statement of effective descent.
On the Occupation Time on the Half Line of Pinned Diffusion Processes
Authors: Yano Yuko
Published: November 2007

The aim of the present paper is to generalize Lévy’s result of the occupation e time on the half line of pinned Brownian motion for pinned diﬀusion processes. An asymptotic behavior of the distribution function at the origin of the occupation time

Γ_+(t)

and limit theorem for the law of the fraction

Γ_+(t)/t

when

t → ∞

are studied. An expression of the distribution function by the Riemann–Liouville fractional integral for pinned skew Bessel diffusion processes is also obtained. Krein’s spectral theory and Tauberian theorem play important roles in the proofs.
Duality‐Mathematics
Authors: Gao David Yang
Published: November 2007

The sections in this article are

Introduction

Framework in Quadratic Minimization

Canonical Lagrangian Duality Theory

Primal‐Dual Solutions and Central Path

Canonical Duality Theory in Nonconvex Systems

Application in Nonconvex Variational Problem

Applications in Global Optimization

Conclusions
Electromagnetic Shielding
Authors: Celozzi Salvatore , Lovat Giampiero , Araneo Rodolfo
Published: November 2007

The sections in this article are

Basic Definitions

Electrostatics

Magnetostatics

Electromagnetics

Plane Waves Against Multilayer Planar Shields

Characterization of Near‐Field Sources

Apertures Effects on Shielding Performance

Shielding Performance Measurement and Standards

Shielding Effectiveness of Metallic Enclosures

Current Research Topics
Thermal Spray Coatings
Authors: Fauchais P. , Vardelle A.
Published: November 2007

Thermal spraying is a group of processes in which finely divided metallic or nonmetallic surfacing materials are deposited
in a molten or semi‐molten condition
on a
prepared substrate
to form a spray deposit. The surfacing material may be in the form of powder, rod, cord, or wire, and the different spraying processes are generally categorized into two groups according to the method of heat generation: combustion or electrical. This article is restricted to electrical processes: plasmas jets (nontransferred direct current arcs or induction discharges), wire arcs, and transferred arcs. Nowadays, thermal spray is part of engineering technology for wear protection, thermal insulation or barriers, oxidation protection, corrosion or oxidation resistance, abradable seals, electrically conductive or insulating materials, dimensional restoration or manufacture, free‐standing shapes, and medical implants.
Trifluoromethylboranes and ‐Borates: New Synthetic Strategies and Applications
Authors: Finze Maik , Bernhardt Eduard , Willner Helge
Published: November 2007

The synthesis of salts with the [B(CF3)4]− anion has been the starting point for new developments in the field of trifluoromethylboron chemistry. In contrast to the previous syntheses of (CF3)nB derivatives (n=1–3), achieved exclusively by CF3 transfer, the synthesis of the [B(CF3)4]− anion was accomplished by fluorination of the [B(CN)4]− anion with ClF or ClF3 in anhydrous HF. Owing to its thermal and chemical stability, [B(CF3)4]− is an attractive weakly coordinating anion. However, in concentrated sulfuric acid one of the four CF3 groups is solvolyzed to a CO ligand to yield the neutral borane carbonyl (CF3)3BCO. It has been shown that the borane carbonyl compound is a versatile synthetic building block, and numerous reactions have been investigated. The addition of nucleophiles to the C atom of the CO ligand is favored, and examples for new derivatives are the anions [(CF3)3BCPnic]− (Pnic=N, P, As). Under certain conditions, ligand‐exchange reactions are also observed, for example, the formation of (CF3)3BNCH. Finally, the borane carbonyl compound is a component of the conjugated Brønsted–Lewis superacid HF/(CF3)3BCO.
A new measure of clustering effectiveness: Algorithms and experimental studies
Authors: Dang E.K.F. , Luk R.W.P. , Ho K.S. , Chan S.C.F. , Lee D.L.
Published: November 2007

We propose a new optimal clustering effectiveness measure, called CS1, based on a combination of clusters rather than selecting a single optimal cluster as in the traditional MK1 measure. For hierarchical clustering, we present an algorithm to compute CS1, defined by seeking the optimal combinations of disjoint clusters obtained by cutting the hierarchical structure at a certain similarity level. By reformulating the optimization to a 0‐1 linear fractional programming problem, we demonstrate that an exact solution can be obtained by a linear time algorithm. We further discuss how our approach can be generalized to more general problems involving overlapping clusters, and we show how optimal estimates can be obtained by greedy algorithms.
Protein tyrosine kinases as new potential targets against human schistosomiasis
Authors: Dissous Colette , Ahier Arnaud , Khayath Naji
Published: November 2007

In spite of the numerous efforts made to control their transmission, parasite schistosomes still represent a serious public health concern and a major economic problem in many developing countries. Praziquantel (PZQ) is the drug of choice for the treatment of schistosomiasis and the only one that is available for mass chemotherapy. However, its widespread use and its inefficacy on juvenile parasites raise fears that schistosomes will develop drug resistance, and make the development of alternative drugs highly desirable. Protein tyrosine kinases (PTKs) are key molecules that control cell differentiation and proliferation and they already represent important targets for molecular cancer therapy. The recent characterization in Schistosoma mansoni of several cytosolic and receptor PTKs, with properties similar but also divergent from their vertebrate counterparts, opens new perspectives for the development of novel strategies in chemotherapy of schistosomiasis, which could be based on the use of parasite‐specific tyrosine phosphorylation inhibitors. BioEssays 29:1281–1288, 2007. © 2007 Wiley Periodicals, Inc.
Androgen signaling and its interactions with other signaling pathways in prostate cancer
Authors: Kaarbø Mari , Klokk Tove I. , Saatcioglu Fahri
Published: November 2007

Prostate cancer is the most frequently diagnosed non‐skin cancer and the third leading cause of cancer mortality in men. In the initial stages, prostate cancer is dependent on androgens for growth, which is the basis for androgen ablation therapy. However, in most cases, prostate cancer progresses to a hormone refractory phenotype for which there is no effective therapy available at present. The androgen receptor (AR) is required for prostate cancer growth in all stages, including the relapsed, “androgen‐independent” tumors in the presence of very low levels of androgens. This review focuses on AR function and AR‐target genes and summarizes the major signaling pathways implicated in prostate cancer progression, their crosstalk with each other and with AR signaling. This complex network of interactions is providing a deeper insight into prostate carcinogenesis and may form the basis for novel diagnostic and therapeutic strategies. BioEssays 29:1227–1238, 2007. © 2007 Wiley Periodicals, Inc.
Bacterial L‐forms require peptidoglycan synthesis for cell division
Authors: Casadesús Josep
Published: November 2007

Cell‐wall‐less bacterial variants, or L‐forms, have been described in many bacterial species under laboratory conditions, in infected eukaryotic cell cultures and inside animals. Of special interest for human health is the formation of L‐forms as a consequence of specific antibiotic treatments, and the potential involvement of L‐forms in persistent and relapsing infections. An old enigma about L‐forms is how they can divide in the absence of cell wall synthesis, since septum formation is an essential requisite for cell division. However, the classical definition of L‐forms as cell‐wall‐less bacterial variants may need a revision to accomodate recent observations by Richard d'Ari and coworkers:1 genetic and biochemical evidence indicates that E. coli L‐forms induced by β‐lactam antibiotics do contain small amounts of peptidoglycan, essential for their growth and probably required for septum formation. If these observations are extrapolated to all known L‐forms, the very concept of cell‐wall‐less bacteria may need revision, and be restricted to mycoplasmas and their relatives. BioEssays 29:1189–1191, 2007. © 2007 Wiley Periodicals, Inc.
On the usage of agricultural raw materials – energy or food? An assessment from an economics perspective
Authors: Lenk Fabian , Bröring Stefanie , Herzog Philipp , Leker Jens
Published: November 2007

Bioenergies are promoted across the globe as the answer for global warming and the chance to reduce dependency from fossil energy sources. Despite the fact that renewable energy sources offer the opportunity to reduce CO2 emission and present a chance to increase agricultural incomes, they also come along with some drawbacks that have been mostly neglected in the current discussion. This paper seeks to build a basis for discussing the impacts of the growing subsidization of bioenergy and the resulting usage competition of agricultural raw materials between foods and energy. To assess the usage competition and the subsidization of bioenergy, this article employs a welfare economics perspective associated with an emphasize on the construct of externalities. This will help to foster the discussion on the further subsidization of bioenergy, where funding for R&D on new ways of using non‐food raw materials ought to play a significant role.
High‐resolution 3‐D imaging of living cells in suspension using confocal axial tomography
Authors: Renaud Olivier , Viña Jose , Yu Yong , Machu Christophe , Trouvé Alain , Van der Voort Hans , Chalmond Bernard , Shorte Spencer L.
Published: November 2007

Conventional flow cytometry (FC) methods report optical signals integrated from individual cells at throughput rates as high as thousands of cells per second. This is further combined with the powerful utility to subsequently sort and/or recover the cells of interest. However, these methods cannot extract spatial information. This limitation has prompted efforts by some commercial manufacturers to produce state‐of‐the‐art commercial flow cytometry systems allowing fluorescence images to be recorded by an imaging detector. Nonetheless, there remains an immediate and growing need for technologies facilitating spatial analysis of fluorescent signals from cells maintained in flow suspension. Here, we report a novel methodological approach to this problem that combines micro‐fluidic flow, and microelectrode dielectric‐field control to manipulate, immobilize and image individual cells in suspension. The method also offers unique possibilities for imaging studies on cells in suspension. In particular, we report the system's immediate utility for confocal “axial tomography” using micro‐rotation imaging and show that it greatly enhances 3‐D optical resolution compared with conventional light reconstruction (deconvolution) image data treatment. That the method we present here is relatively rapid and lends itself to full automation suggests its eventual utility for 3‐D imaging cytometry.
Cancer vaccines
Authors: Kiessling R , Choudhury A
Published: November 2007

Stormy fortunes
Retroperitoneal sarcoma (Br J Surg 2007; 94: 1057–1058)
Authors: Shukla P J , Barreto S G , Shrikhande S V
Published: November 2007

The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses should be sent electronically via the BJS website (www.bjs.co.uk). All letters will be reviewed and, if approved, appear on the website.A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length.
Complexity in Modeling and Understanding Protonation States: Computational Titration of HIV‐1‐Protease–Inhibitor Complexes
Authors: Tripathi Ashutosh , Fornabaio Micaela , Spyrakis Francesca , Mozzarelli Andrea , Cozzini Pietro , Kellogg Glen E.
Published: November 2007

The computational‐titration (CT) algorithm based on the ‘natural’ Hydropathic INTeractions (HINT) force field is described. The HINT software model is an empirical, non‐Newtonian force field derived from experimentally measured partition coefficients for solvent transfer between octanol and H2O (log Po/w). The CT algorithm allows the identification, modeling, and optimization of multiple protonation states of residues and ligand functional groups at the protein–ligand active site. The importance of taking into account pH and ionization states of residues, which strongly affect the process of ligand binding, for correctly predicting binding free energies is discussed. The application of the CT protocol to a set of six cyclic inhibitors in their complexes with HIV‐1 protease is presented, and the advance of HINT as a virtual‐screening tool is outlined.
Hydropathic Analysis and Comparison of KcsA and Shaker Potassium Channels
Authors: Peng Yong , Scarsdale J. Neel , Kellogg Glen E.
Published: November 2007

The similarity in structure of potassium (K+) channels from different families has been revealed by only recently available crystallographic 3D structural data. The hydropathic analysis presented in this work illuminates whether homologous residues perform the same functions in channels that use different gating mechanisms. We calculated and compared the hydropathic profiles of two K+ channels, KcsA and Kv1.2 (the latter a member of the Shaker family), at their pore‐forming domain. Quantitative information describing important interactions stabilizing the protein beyond obvious secondary‐structure elements was extracted from the analysis and applied as a template for subsequent molecular‐dynamics (MD) analyses. For example, two key groups of interactions, defining the turns that connect the transmembrane helices and responsible for the orientation of the pore helix, were identified. Our results also indicate that Asp80 and Asp379 play a similar role in stabilizing the P‐loop of KcsA and Kv1.2, respectively, but to significantly different extents.
Identification of Novel Allosteric Regulators of Human‐Erythrocyte Pyruvate Kinase
Authors: Kharalkar Shilpa S. , Joshi Gajanan S. , Musayev Faik N. , Fornabaio Micaela , Abraham Donald J. , Safo Martin K.
Published: November 2007

Erythrocyte pyruvate kinase (PK) is an important glycolytic enzyme, and manipulation of its regulatory behavior by allosteric modifiers is of interest for medicinal purposes. Human‐erythrocyte PK was expressed in Rosetta cells and purified on an Ni‐NTA column. A search of the small‐molecules database of the National Cancer Institute (NCI), using the UNITY software, led to the identification of several compounds with similar pharmacophores as fructose‐1,6‐bisphosphate (FBP), the natural allosteric activator of the human kinases. The compounds were subsequently docked into the FBP binding site using the programs FlexX and GOLD, and their interactions with the protein were analyzed with the energy‐scoring function of HINT. Seven promising candidates, compounds 1–7, were obtained from the NCI, and subjected to kinetics analysis, which revealed both activators and inhibitors of the R‐isozyme of PK (R‐PK). The allosteric effectors discovered in this study could prove to be lead compounds for developing medications for the treatment of hemolytic anemia, sickle‐cell anemia, hypoxia‐related diseases, and other disorders arising from erythrocyte PK malfunction.
Predicting Aging/Longevity‐Related Genes in the Nematode Caenorhabditis elegans
Authors: Witten Tarynn M. , Bonchev Danail
Published: November 2007

We present a novel mathematical/computational strategy for predicting genes/proteins associated with aging/longevity. The novelty of our method arises from the topological analysis of an organismal longevity gene/protein network (LGPN), which extends the existing cellular networks. The LGPN nodes represent both genes and corresponding proteins. Links stand for all known interactions between the nodes. The LGPN of C. elegans incorporated 362 genes/proteins, 160 connecting and 202 age‐related ones, from a list of 321 with known impact on aging/longevity. A ‘longevity core’ of 129 directly interacting genes or proteins was identified. This core may shed light on the large‐scale mechanisms of aging. Predictions were made, based upon the finding that LGPN hubs and centrally located nodes have higher likelihoods of being associated with aging/longevity than do randomly selected nodes. Analysis singled‐out 15 potential aging/longevity‐related genes for further examination: mpk‐1, gei‐4, csp‐1, pal‐1, mkk‐4, 4O210, sem‐5, gei‐16, 1O814, 5M722, ife‐3, ced‐10, cdc‐42, 1O776Co, and 1O690.
Drug eluting stents versus coronary artery bypass surgery in patients with isolated proximal lesion in left anterior descending artery suffering from chronic stable angina
Authors: Toutouzas Konstantinos , Patsa Chrysoula , Vaina Sophia , Tsiamis Eleftherios , Vavuranakis Manolis , Stefanadi Elli , Spanos Anastasios , Iliopoulos Dimitiros , Panagiotou Mathaios , Chlorogiannis Ioannis , Pattakos Eustratios , Stefanadis Christodoulos
Published: November 2007

Objective: To compare the efficacy of drug eluting stents (DES) compared with bypass surgery (CABG) with left internal mammary artery (LIMA) in patients with single vessel disease suffering from chronic stable angina. Background: There are a limited number of studies investigating this group of patients. Methods: We included 257 consecutive patients with isolated lesion in the proximal segment of left anterior descending artery (LAD). All patients suffered from chronic stable angina or from stress‐induced ischemia. Of 257 patients, 147 underwent DES implantation and 110 CABG with LIMA. All patients were followed‐up clinically for major adverse cardiac events. Results: The baseline demographic and angiographic characteristics were similar between the two groups. In the DES group we used sirolimus‐, paclitaxel‐, and ABT‐578‐eluting stents. The mean duration of hospitalization after CABG was 7.86 ± 3.84 days vs. 1.02 ± 0.19 days after PCI (P < 0.01). The incidence of MACE was 2.72% in the DES and 2.72% in the surgical group during a mean follow‐up period of 18.71 ± 6.27 months for PCI and 18.70 ± 7.31 months for CABG (P = 0.99). There was one cardiac related death in the DES group and two in the surgical group (P = 0.58). There were three reinterventions in the DES group versus none in the surgical group (P = 0.26). Recurrence of angina was observed in 4.08% of pts in the DES group versus 6.36% in the CABG group (P = 0.57). Conclusions: The present study demonstrated that patients suffering from chronic stable angina with isolated lesion in the proximal segment of LAD have excellent long‐term outcome in both surgical and DES treatment. © 2007 Wiley‐Liss, Inc.
Technology preview: X‐ray fused with magnetic resonance during invasive cardiovascular procedures
Authors: Gutiérrez Luis F. , Silva Ranil de , Ozturk Cengizhan , Sonmez Merdim , Stine Annette M. , Raval Amish N. , Raman Venkatesh K. , Sachdev Vandana , Aviles Ronnier J. , Waclawiw Myron A. , McVeigh Elliot R. , Lederman Robert J.
Published: November 2007

Background:

We have developed and validated a system for real‐time X‐ray fused with magnetic resonance imaging, MRI (XFM), to guide catheter procedures with high spatial precision. Our implementation overlays roadmaps—MRI‐derived soft‐tissue features of interest—onto conventional X‐ray fluoroscopy. We report our initial clinical experience applying XFM, using external fiducial markers, electrocardiogram (ECG)‐ gating, and automated real‐time correction for gantry and table movement.

Methods:

This prospective case series for technical development was approved by the NHLBI Institutional Review Board and included 19 subjects. Multimodality external fiducial markers were affixed to patients' skin before MRI, which included contrast‐enhanced, 3D T1‐weighted, or breath‐held and ECG‐gated 2D steady state free precession imaging at 1.5T. MRI‐derived roadmaps were manually segmented while patients were transferred to a calibrated X‐ray fluoroscopy system. Image spaces were registered using the fiducial markers and thereafter permitted unrestricted gantry rotation, table panning, and magnification changes. Static and ECG‐gated MRI data were transformed from 3D to 2D to correspond with gantry and table position and combined with live X‐ray images.

Results:

Clinical procedures included graft coronary arteriography, right ventricular free‐wall biopsy, and iliac and femoral artery recanalization and stenting. MRI roadmaps improved operator confidence, and in the biopsy cases, outperformed the best available alternative imaging modality. Registration errors were increased when external fiducial markers were affixed to more mobile skin positions, such as over the abdomen.

Conclusion:

XFM using external fiducial markers is feasible during X‐ray guided catheter treatments. Multimodality image fusion may prove a useful adjunct to invasive cardiovascular procedures. © 2007 Wiley‐Liss, Inc.
Co‐evolution of non‐linear PLS model components
Authors: Searson Dominic , Willis Mark , Montague Gary
Published: November 2007

The issue of outer model weight updating is important in extending partial least squares (PLS) regression to modelling data that shows significant non‐linearity. This paper presents a novel co‐evolutionary component approach to the weight updating problem. Specification of the non‐linear PLS model is achieved using an evolutionary computational (EC) method that can co‐evolve all non‐linear inner models and all input projection weights simultaneously. In this method, modular symbolic non‐linear equations are used to represent the inner models and binary sequences are used to represent the projection weights. The approach is flexible, and other representations could be employed within the same co‐evolutionary framework. The potential of these methods is illustrated using a simulated pH neutralisation process data set exhibiting significant non‐linearity. It is demonstrated that the co‐evolutionary component architecture can produce results which are competitive with non‐linear neural network‐based PLS algorithms that use iterative projection weight updating. In addition, a data sampling method for mitigating overfitting to the training data is described. Copyright © 2007 John Wiley & Sons, Ltd.
Reduced‐order model for monitoring spectroscopic and chromatographic polymer properties
Authors: Rantow Felix S. , Soroush Masoud , Grady Michael C.
Published: November 2007

A reduced‐order mechanistic polymerization model and its application in the design of a low‐dimension multi‐rate state estimator (soft sensor) for monitoring spectroscopic and chromatographic polymer properties are presented. A model reduction approach is used to simplify a method‐of‐moments mechanistic model. Using this approach, the order (number of the state variables) of the model is reduced from 20 to 7. The soft sensor estimates spectroscopic and chromatographic polymer properties from (a) frequent measurements of the reactor temperature and the flow rates of monomer (n‐butyl acrylate), initiator (t‐butyl peroxy acetate) solution and solvent (xylene) feed streams, and (b) infrequent and delayed measurements of polymer number‐ and weight‐average molecular weights and the concentrations of terminal solvent groups, terminal double bonds and short chain branches. The benefits of using the infrequent measurements in the estimation are shown. The soft sensor is implemented in real‐time, and the calculated continuous estimates of polymer number‐ and weight‐average molecular weights and the concentrations of solvent, terminal double bonds and short chain branches are compared to the corresponding chromatographic and spectroscopic measurements. Copyright © 2007 John Wiley & Sons, Ltd.
Chemical Clockwise Tridifferentiation of α‐ and β‐Cyclodextrins: Bascule‐Bridge or Deoxy‐Sugars Strategies
Authors: Bistri Olivia , Sinaÿ Pierre , Jiménez Barbero Jesùs , Sollogoub Matthieu
Published: November 2007

The selective and efficient functionalisation of large concave molecules is a chemical challenge opening the door to various applications, such as artificial enzymes. We propose here a method, based on deprotection of benzylated cyclodextrins, to selectively access a variety of complex structures with two or three new different functionalities on the primary platform. Our strategy is based on a mechanistic hypothesis involving the approach of an aluminium reagent between the primary oxygen atom and the endocyclic one of the same sugar unit. Due to its cyclic directionality, a change in steric hindrance on a given position of the cyclodextrin has a different effect on the clockwise or the counterclockwise directions. This concept is illustrated and exploited in two complementary ways: deoxygenation of the primary position of two diametrically opposed sugars induces a debenzylation reaction on the neighbouring clockwise sugars of α‐ and β‐cyclodextrins. Reversible capping, or bascule‐bridging, of the same pair of sugars has the same effect on the debenzylation of α‐cyclodextrin, but induces an important change of the geometry of β‐cyclodextrin, hence allowing the selective access to yet another functionalisation pattern. A combined use of deoxygenation and bascule‐bridging allows the access to an α‐cyclodextrin with its three pairs of primary functions differentiated and ready for further modifications. Bascule‐bridge or deoxy‐sugars are two complementary means to operate steric decompression and induce selective reactions to efficiently access a number of new patterns of functionalities on concave molecules.
Prognostic significance of mesenteric tumor nodules in patients with stage III colorectal cancer
Authors: Lo Dorothy S. , Pollett Aaron , Siu Lillian L. , Gallinger Steve , Burkes Ronald L.
Published: November 2007

BACKGROUND.

Tumor nodules are occasionally found in adjacent mesentery of colorectal cancer specimens and are felt to reflect a worse prognosis. The clinical significance of mesenteric tumor nodules was investigated.

METHODS.

A review of 786 patients with stage III colorectal cancer referred between 1995 and 1999 was undertaken. TNM staging was standardized by considering mesenteric nodules separately and not assigning them to T or N categories. Survival analyses were performed.

RESULTS.

Mesenteric tumor nodules were found in 116 (14.8%) patients: 48 (41.4%) with colon cancer and 68 (58.6%) rectal cancer. Mean age at surgery was 63 years. Adjuvant chemotherapy was given to 84.8% of colon cancer patients. Two (2.9%) rectal cancer patients received neoadjuvant chemoradiation, and 63 (92.6%) received adjuvant therapy (chemotherapy and/or radiation). In the cohort with mesenteric nodules, the median time to progression was 23.1 months, the median 5‐year disease‐free survival was 35%, and the median overall survival (OS) was 47.9 months, with 44% OS at 5 years. In the 19 (16.4%) patients with mesenteric nodules and no lymph nodes the 5‐year OS was 60% (SEER stage II 5‐year survival 82.5%), whereas in 97 patients who were lymph node‐positive the 5‐year OS was 40% (SEER 5‐year survival stage IIIc 44.3%; stage IV 8.1%).

CONCLUSIONS.

In comparison to SEER survival data, the presence of mesenteric nodules appears to worsen the prognosis of any T/N0 disease to that of overall stage III disease. Mesenteric nodules with any T/N+ disease had prognosis similar to that of stage IIIC disease, but the prognosis was better than M1 disease. Cancer 2008. © 2007 American Cancer Society.
Barriers to recruiting underrepresented populations to cancer clinical trials: A systematic review
Authors: Ford Jean G. , Howerton Mollie W. , Lai Gabriel Y. , Gary Tiffany L. , Bolen Shari , Gibbons M. Chris , Tilburt Jon , Baffi Charles , Tanpitukpongse Teerath Peter , Wilson Renee F. , Powe Neil R. , Bass Eric B.
Published: November 2007

Racial and ethnic minorities, older adults, rural residents, and individuals of low socioeconomic status are underrepresented among participants in cancer‐related trials. The authors conducted a systematic review to determine the barriers to participation of underrepresented populations in cancer‐related trials. Their search included English‐language publications that reported original data on the recruitment of underrepresented groups to cancer treatment or prevention trials between 1966 and December 2005 in multiple electronic databases. They also hand‐searched titles in 34 journals from January 2003 to December 2005 and they examined reference lists for eligible articles. Titles and abstracts were reviewed to identify relevant studies. Data on barriers to participation were synthesized both qualitatively and based on statistically significant associations with trial enrollment. Of 5257 studies that were cited, 65 studies were eligible for inclusion in the current analysis, including 46 studies on recruitment into cancer therapeutic trials, 15 studies on recruitment into prevention trials, and 4 studies on recruitment into both prevention and treatment trials. Numerous factors were reported as barriers to participation in cancer‐related trials. However, only 20 of the studies reported statistically significant associations between hypothesized barriers and enrollment. The available evidence had limitations in quality regarding representativeness, justification of study methods, the reliability and validity of data‐collection methods, potential for bias, and data analysis. The results indicated that underrepresented populations face numerous barriers to participation in cancer‐related trials. The current systematic review highlighting the literature on recruitment of underrepresented populations to cancer trials and may be used as the evidence base toward developing an agenda for etiologic and intervention research to reduce the disparities in participation in cancer‐related trials. Cancer 2008. © 2007 American Cancer Society.
A 35‐year retrospective study of carcinoid tumors in Taiwan
Authors: Li Anna Fen‐Yau , Hsu Chih‐Yi , Li Alice , Tai Ling‐Chen , Liang Wen‐Yih , Li Win‐Yin , Tsay Shyh‐Haw , Chen Jeou‐Yuan
Published: November 2007

BACKGROUND.

A comprehensive study of carcinoid tumors from United States‐based databases indicated that the small intestine, colon, rectum, and bronchopulmonary system are common locations for carcinoid tumors. In addition, certain carcinoid tumors, such as rectal carcinoids, appeared to be overrepresented in nonwhite populations in the United States. High frequencies of associated noncarcinoid malignancies were reported in some articles. The objective of the current study was to address the organ distribution, frequency of metastasis, and survival rates of carcinoid tumors and the associated noncarcinoid tumors in Taiwanese, Asian populations.

METHODS.

Two hundred twenty‐eight patients with carcinoid tumors were identified and evaluated from the surgical pathology files and medical records of the Veterans General Hospital, Taipei, Taiwan from January 1970 to December 2005.

RESULTS.

In 228 carcinoid tumors that were analyzed, the rectum (60.5%) was the most common location followed by the lung (20.2%) and the thymus (6.6%). Metastatic lesions were demonstrated in 16.2% of patients. Disease extent was associated with survival. The 5‐year survival rates for patients with localized, regional metastatic, and distant metastatic disease were 94.1%, 49.1%, and 0%, respectively (P < .001). Associated noncarcinoid malignancies were noted in 14% of patients with carcinoids, mainly in the gastrointestinal tract (52.9%), lung, and genitourinary system.

CONCLUSIONS.

A different organ distribution of carcinoids was observed in Taiwanese patients, who had with significantly more carcinoids located in the rectum and thymus compared with patients in Western countries. The patients with carcinoids in the current study had a high possibility of developing associated, noncarcinoid neoplasms. Surveillance of the colon, stomach, lung, and genitourinary system for second malignant tumors is recommended. Cancer 2008. © 2007 American Cancer Society.
Comparison of 7 staging systems for patients with hepatocellular carcinoma undergoing transarterial chemoembolization
Authors: Cho Yun Ku , Chung Jin Wook , Kim Jae Kyun , Ahn Yong Sik , Kim Mi Young , Park Yoon Ok , Kim Wan Tae , Byun Jong Hoon
Published: November 2007

BACKGROUND.

Many liver staging systems have been proposed for patients with hepatocellular carcinoma after locoregional therapy; however, controversies persist regarding which system is the best. In this study, the authors compared the performance of 7 staging systems in a cohort of patients with hepatocellular carcinoma who underwent transarterial chemoembolization.

METHODS.

In total, 131 patients with hepatocellular carcinoma who underwent transarterial chemoembolization between August 1998 and February 2005 were included in the study. Demographic, laboratory, and tumor characteristics were determined at diagnosis and before therapy. At the time of censorship, 109 patients had died (83.2%). Predictors of survival were identified by using the Cox proportional hazards model. The likelihood‐ratio chi‐square statistic and the Akaike Information Criterion were calculated for 7 prognostic systems to evaluate their discriminatory ability. Comparisons of the survival rate between each stage were performed to evaluate the monotonicity of the gradients using Kaplan‐Meier estimation and the log‐rank test.

RESULTS.

The 5‐year survival rate for the entire cohort was 13.6%. The independent predictors of survival were serum albumin level (≤3.4 g/dL), the presence of ascites, serum α‐fetoprotein level (>60 ng/mL), and portal or hepatic vein tumor thrombosis (P= .001,P= .001,P= .004, andP= .000, respectively). The Cancer of the Liver Italian Program classification system was superior to the other 6 prognostic systems regarding discriminatory ability and the monotonicity of the gradients.

CONCLUSIONS.

In this comparison of many staging systems, the Cancer of Liver Italian Program system provided the best prognostic stratification for a cohort the patients with hepatocellular carcinoma who underwent transarterial chemoembolization. Cancer 2008. © 2007 American Cancer Society.
Why complex systems engineering needs biological development
Authors: Banzhaf W. , Pillay N.
Published: November 2007

Here we shall discuss the need of Complex Systems Engineering to adopt principles from natural development of complex biological organisms—besides principles of natural evolution—to acomplish the type of performance that biology achieves regularly. We shall situate Complex Systems Engineering and discuss an example of how it could be employed. © 2007 Wiley Periodicals, Inc. Complexity, 2007
The influence of a ferroelectric domain wall on the fabrication of a pyroelectric laser energymeter
Authors: Satapathy S. , Gupta P. K. , Wadhawan V. K.
Published: November 2007

A region across a ferroelectric domain wall has been scanned, using an Nd:YAG laser beam (beam size 440 μm), in a thin crystal of TGS (triglycine sulphate), cut normal to the polar axis and the pyroelectric response of the crystal has been recorded. If a laser pulse of fixed beam size falls on the domain completely, then the output pyroelectric signal is maximum. But when the laser beam (diameter of beam greater than width of domain wall) falls on the domain wall, the pyroelectric signals from two opposite domains tries to cancel each other and net signal depends on the position of laser beam across the domain wall. When the domain wall lies in the middle of the laser beam the output pyroelctric signal will be zero. In our experiment when beam of size 440 μm falls on positive domain the pyroelectric voltage of ‐2.76 mV recorded and when beam starts crossing the domain wall (i.e from positive domain to negative domain), the pyoelectric signal changes its sign from negative to positive through zero. After 220 μm the signal decreased to minimum and again increases to maximum (+2.46 mV) in opposite direction after 440 μm i.e when beam falls on the negative domain completely. This shows that the polarization in the domain wall region (separating two domains) is zero i.e the paraelectric nature of domain wall. So before detector fabrication the sample must be poled sufficiently to avoid the non uniformity of pyroelectric signal due to the domain wall. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth and characterization of a new semi organic NLO material: L‐tyrosine hydrochloride
Authors: Natarajan S. , Shanmugam G. , Martin Britto Dhas S. A.
Published: November 2007

Single crystals of L‐Tyrosine hydrochloride were grown by using the submerged seed solution method. The grown crystals were characterized by using single crystal X‐ray diffraction. Functional groups and the modes of vibrations were identified by FTIR spectroscopy. The TGA/DTA studies showed that the crystal is stable up to 232°C. Microhardness study revealed that the crystal is a hard material. It is transparent in the entire visible region. The SHG efficiency was determined by the Kurtz and Perry method. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystal structure refinement of the ternary compound Cu2SnTe3 by X‐ray powder diffraction
Authors: Delgado G. E. , Mora A. J. , Marcano G. , Rincón C.
Published: November 2007

The ternary compound Cu2SnTe3 crystallizes in the Imm2 (Nº 44) space group, Z = 2, with a = 12.833(4) Å, b = 4.274(1) Å, c = 6.043(1) Å, V = 331.5(1) Å3. Its structure was refined from X‐ray powder diffraction data using the Rietveld method. The refinement of 25 instrumental and structural variables led to Rp = 10.2%, Rwp = 11.8%, Rexp = 7.7%, RB = 10.6%, S = 1.6 and χ2 = 2.6, for 5501 step intensities and 163 independent reflections. This compound is isostructural with Cu2GeSe3, and consists of a three‐dimensional arrangement of slightly distorted CuTe4 and SnTe4 tetrahedra connected by common corners. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of substrate temperature on the structure of ZnO:Al thin films
Authors: Rozati S. M. , Akeste Sh.
Published: November 2007

ZnO: Al films were prepared using low cost spray pyrolysis technique. The dependence of the physical properties on the substrate temperature was studied. The best films obtained at 500°C substrate temperature with preferred [002] orientation. The sheet resistance decreases with increased substrate temperature, and values as low as Rsh = 207 Ω/cm2 are reached for substrate temperature of 500°C. The optical transmittance of films increased by increasing the substrate temperature and received to 75% at 500°C. (© 2007 WILEY ‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Continuing Care of the Renal Patient: A Guide for Nurses
Authors: Leatherland Samantha
Published: November 2007

The purpose of this article is to examine aspects of chronic renal failure in order to create a guide for nurses to help them manage patients with this condition more effectively. This is a literature review, with the literature search conducted using online databases and health science libraries. Two themes pertinent to chronic renal failure management‐coping and adaptation and self‐efficacy and empowerment‐are discussed. Reflections from my practice are related to the discussion, and as a result of the findings, suggestions are made on how nursing practice and research can be improved in the area of chronic renal failure.
Fine needle aspiration biopsy of the prostate gland
Authors: Maksem John A. , Berner Aasmund , Bedrossian Carlos
Published: November 2007

With the worldwide acceptance of mechanically assisted, ultrasound guided thin needle biopsy of the prostate gland, prostate fine needle aspiration (FNA) has fallen out of favor with both urologists and cytopathologists. Nonetheless, given today's trend to submit from 12 to 18 core biopsies per patient, prostate FNA remains less expensive, more expedient and more economical than any other sampling method so far developed. This short overview presents prostate FNA as a sensitive, specific and reliable diagnostic modality that should not be dismissed, as an anachronism, from the diagnostic armamentarium of either the urologist or the pathologist. Diagn. Cytopathol. 2007;35:778–785. © 2007 Wiley‐Liss, Inc.
Fine‐needle aspiration cytology of soft tissue lesions: Diagnostic challenges
Authors: Domanski Henryk A.
Published: November 2007

Clinical and radiographic data provide important information in the evaluation of soft tissue lesions/neoplasms. Morphologic tissue and cytologic examination is considered to be a necessary part of the diagnostic work‐up.

The standard procedure for obtaining tumor tissue for morphologic evaluation has been incisional (open) or core needle biopsy. An increasing use of minimally invasive diagnostic procedures has resulted in better acceptance of fine‐needle aspiration cytology (FNAC) in the diagnosis of soft tissue lesions.

This article discusses challenges in FNAC of soft tissue lesions based on the experience at a multidisciplinary referral sarcoma center.

Obtaining sufficient specimens from deeply seated small and necrotic/cystic lesions is technically a potential pitfall and misdiagnosis of cells from reactive zones surrounding the tumor as well as the correct evaluation of spindle cell lesions, rare soft tissue neoplasms, and “new entities” lacking reproducible cytological criteria are other important challenges in FNAC of soft tissues.

The successful cytological evaluation of soft tissue lesions requires the application of strict, reproducible morphological criteria in the context of the clinical findings as well as ancillary techniques. The minimal criteria for diagnostic intervention in various clinical settings and the relative advantages and disadvantages of FNAC must be understood. FNAC of soft tissue lesions is facilitated when limited to specialized orthopedic‐oncologic centers with a well‐integrated multidisciplinary team and experience in the evaluation and therapy of soft tissue lesions. Diagn. Cytopathol. 2007;35:768–773. © 2007 Wiley‐Liss, Inc.
Cellular adequacy for thyroid aspirates prepared by ThinPrep: How many cells are needed?
Authors: Michael Claire W. , Pang Yijun , Pu Robert T. , Hasteh Farnaz , Griffith Kent A.
Published: November 2007

Although it is well established that ThinPrep introduces artifacts to thyroid aspirates, no criteria have been established for adequacy of such specimens. This study evaluates the adequate number of cells needed to establish the correct diagnosis based on ThinPrep alone. A total of 218 thyroid aspirates prepared by TP with surgical pathology follow‐up were reviewed. The cellularity was calculated as follows: Count the total number of clusters, randomly select 10 clusters and count each, calculate the average number per cluster and multiply by the total number of clusters. A minimum number of 6 clusters with 10 cells each was arbitrary established to assume adequacy for a definitive diagnosis. Cytologic diagnoses were classified as: Nondiagnostic (ND), cystic contents, thyroiditis, nodular hyperplasia (NH), follicular/Hurthle (F/H) cell lesion, F/H cell neoplasm, and carcinoma: qualify. Histologic diagnoses were classified as: Cyst (colloid or otherwise), thyroiditis, NH, F/H adenoma, F/H carcinoma, carcinoma: qualify. Appropriate treatment triage was considered to be clinical for the former 4 cytologic categories and surgical for the latter 3 with ND warranting repeat aspiration. The results were subjected to logistic regressions analysis and contingency tables correlating the number of cells with the cytologic and histologic diagnosis as well as with treatment triage. Cellularity of sample was ranked in 10 deciles according to the number of cells and in 4 quartiles according to the number of clusters. The agreement percentage, for both diagnostic and treatment, was computed for each decile and quartile. 146 (67%) cases had cells and received a diagnosis while 72 (33%) were acellular. Of the 146 cases, 21 contained histiocytes or colloid only. 91/146 (62.3%) were correctly diagnosed and 123/146 (84.3%) would have been correctly triaged for treatment based upon the cytologic diagnosis. Samples with 180 cells or fewer had an agreement rate below 50%. Agreement rate increases to 80% when cellularity is 180–320. Above 320 agreement rate remains high but not uniformly. Total number of clusters did not play an independent role and only the number of cells per cluster had a significant correlation with diagnostic agreement. A 25‐cell increase in average cells per cluster increases the odds of agreement between diagnoses by 65%. Diagn. Cytopathol. 2007;35:792–797. © 2007 Wiley‐Liss, Inc.
Fine‐needle aspiration in the diagnosis of head and neck lesions: A review and discussion of problems in differential diagnosis
Authors: Layfield Lester J.
Published: November 2007

Fine‐needle aspiration (FNA) has become the predominant initial diagnostic technique for lesions at a number of sites within the head and neck. The technique has achieved this level of usage because it is relatively inexpensive, rapid to perform, well accepted by patients, associated with low morbidity, and has a relatively high diagnostic accuracy. Sites in the head and neck amenable to FNA include the thyroid, cervical masses and nodules, salivary glands, intraoral lesions and lesions in the paraspinal area and base of skull. Diagnostic accuracy is dependent on the site of aspiration as well as the skill of the individual performing and interpreting the FNA. Studies have shown that FNA is most accurate when the individual interpreting the FNA is the same individual who obtained the aspirate material. Each site undergoing FNA within the head and neck is associated with a set of differential diagnoses and diagnostic challenges which will be discussed. Diagn. Cytopathol. 2007;35:798–805. © 2007 Wiley‐Liss, Inc.
On transmission techniques for multi‐antenna W‐CDMA systems
Authors: da Silva Mário Marques , Correia Américo M. C. , Dinis Rui
Published: November 2007

In this paper we present and evaluate a new pre‐processing scheme for Multiple Input Multiple Output (MIMO) channels. Its performance is compared with other MIMO schemes proposed for the downlink of Wideband‐Code Division Multiple Access (W‐CDMA) systems, namely a variation of the Beam Forming (BF), entitled Beam‐Selective Transmit Diversity (BSTD) or post‐processing schemes, such as the Alamouti‐like MIMO or the Vertical Bell Laboratories Layered Space‐Time (V‐BLAST) MIMO scheme. It is assumed that the Base Station (BS) hasM ⩾ 2 transmit antennas and the Mobile Station (MS) receiver has space enough to accommodateN = 2 uncorrelated receive antennas.

It is shown that the proposed pre‐processing scheme allows receivers with very low complexity, contrarily to the case where a post‐processing approach is followed, simplifying the MS receiver. Therefore, the proposedM × NMIMO pre‐processing scheme can be seen as an alternative to post‐processing schemes. It is also shown that the pre‐processing scheme for MIMO channels tends to achieve the best performance in most scenarios, being followed by the BSTD, which allows interference cancellation and provides diversity. Copyright © 2007 John Wiley & Sons, Ltd.