bluuebunny/crossref_metadata_2025 huggingface dataset:
Cr(VI)‐containing wastewater treatment by means of ion exchange on weak‐ and strong‐base anion exchangers
Authors: Untea I. , Tudorache Elena , Neagu Violeta
Published: October 2002

The aim of this research work was a thermodynamic and kinetic study of the retention of Cr(VI) ions from a K2CrO4 solution on macroporous weak‐ and strong‐base anion exchangers, Lewatit M 64 A and Lewatit MP 500 A, respectively. Also, the correlations among the ion‐exchange rate, the retention capacity of Cr(VI), and some process parameters were established. The parameters studied mainly were the concentration of Cr(VI) ions and the type of the counterions coupled with active groups from the anion exchangers. The results led to the conclusion that, for the Lewatit M 64 A resin, there is the following order of the Cr(VI) retention capacity: RCl > R2SO4 > ROH, while for the strong‐base anion exchanger, the retention capacity for the Cr(VI) ions is different: ROH > RCl > R2SO4. In the Cl− form, both anion exchangers have the same retention‐capacity values. On the other side, the weak‐base anion exchanger in SO and OH− forms presents the lowest retention‐capacity values. The process kinetics also presents some differences: for the Lewatit M 64 A resin, the ion‐exchange rate has lower values, especially in the OH− form. This result is attributed to the increase of the OH− ion concentration in the solution and its presence hinders the dissociation of the active groups of a weak‐base anion exchanger. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2093–2098, 2002
Spatial distribution of fiber types within skeletal muscle fascicles from Standardbred horses
Authors: Grotmol Sindre , Totland Geir K. , Kryvi Harald , Breistøl Arild , Essén‐Gustavsson Birgitta , Lindholm Arne
Published: October 2002

Skeletal muscle fascicles from superficial and deep portions of semitendinosus (ST) and gluteus medius (GM) muscles from Standardbred trotters were analyzed with regard to muscle fiber type proportion (types I, IIA, and IIB) and spatial distribution. Muscle fibers within a fascicle were divided into four layers (L1–4) from the fascicle periphery toward the center. The observed proportions of fiber types among layers were found to be statistically significantly different from a random distribution of fiber types. Type IIB fibers predominated in the peripheral layer, type I fibers prevailed in the layer underneath, and proportions close to the mean of the whole fascicles were observed in the central layer. This pattern of spatial distribution of fiber types within the layers of the fascicles was observed at all four muscle sampling sites. The functional significance of the common pattern is unknown, but possible functional roles are discussed. Anat Rec 268:131–136, 2002. © 2002 Wiley‐Liss, Inc.
Knowledge integration in virtual teams: The potential role of KMS
Authors: Alavi Maryam , Tiwana Amrit
Published: October 2002

Virtual teams are becoming a preferred mechanism for harnessing, integrating, and applying knowledge that is distributed across organizations and in pockets of collaborative networks. In this article we recognize that knowledge application, among the three phases of knowledge management, has received little research attention. Paradoxically, this phase contributes most to value creation. Extending communication theory, we identify four challenges to knowledge integration in virtual team environments: constraints on transactive memory, insufficient mutual understanding, failure in sharing and retaining contextual knowledge, and inflexibility of organizational ties. We then propose knowledge management system (KMS) approaches to meet these challenges. Finally, we identify promising avenues for future research in this area.
Exact permutation tests for unreplicated factorials
Authors: Pesarin Fortunato , Salmaso Luigi
Published: October 2002

Exact permutation testing of effects in unreplicated two‐level multifactorial designs is developed based on the notion of realigning observations and on paired permutations. This approach preserves the exchangeability of error components for testing up to k effects. Advantages and limitations of exact permutation procedures for unreplicated factorials are discussed and a simulation study on paired permutation testing is presented. Copyright © 2002 John Wiley & Sons, Ltd.
Electrical impedance tomography via filtered‐back projection of fan current distribution: A numerical simulation
Authors: De Simone B.C. , Siciliano R. , Pachi′ A. , Cametti C. , De Luca F.
Published: October 2002

An approach to electrical impedance tomography (EIT) data acquisition inspired by NMR‐filtered back‐projection imaging with fan isochromat distribution is proposed. A current projection is generated by injecting current at a certain point of the sample and simultaneously collecting the current itself at different points on the half space opposite the point of current injection. After that, the injection is shifted to another point and collected as above and so on. A very simple algebra and software support the numerical simulations. This method is expected to be more sensitive than the traditional method based on potential measurements. A preliminary low resolution experiment is presented. Bioelectromagnetics 23:516–521, 2002. © 2002 Wiley‐Liss, Inc.
Verapamil protective effect on natural and artificial magnetic field cardiovascular impact
Authors: Gmitrov Juraj , Ohkubo Chiyoji
Published: October 2002

Previously we found an opposite effect of artificial static magnetic field (SMF) and natural geomagnetic field (GMF) on arterial baroreceptors. A 0.35 T SMF increased baroreflex sensitivity (BRS), whereas GMF disturbance decreased BRS. Here, we investigated interrelated impacts on arterial baroreceptors of 0.35 T SMF, generated by Nd2‐Fe14‐B alloy magnets, GMF, and verapamil, a Ca2+ channel blocking agent. We measured BRS in rabbits before and after local SMF exposure of sinocarotid baroreceptors or after simultaneous SMF and verapamil application, in conjunction with geomagnetic disturbance during actual experimental run (determined by K‐index) and geomagnetic disturbance over the preceding 24 h of each experiment (Ak‐index). BRS was estimated from peak responses of mean arterial pressure (MAP) and heart rate, expressed as percentages of the resting values preceding each pair of pressure (phenylephrine) and depressor drug (nitroprusside) injections. Prior to verapamil and/or SMF application we found a significant positive correlation of K‐index with MAP (t = 2.39, P = .021, n = 44), but negative with BRS (t = −4.60, P = .0003, n = 44), and found a negative correlation of Ak‐index with BRS (t = −2.7, P = 0.01, n = 44). SMF induced an increase in BRS (0.79 ± 0.1 vs. 1.15 ± 0.1 bpm%/mmHg%, initial value vs. SMF exposure, P < .0002, n = 26). Verapamil infusion blocked the SMF and GMF effect on BRS, indicating Ca2+ channels as a possible site of both fields' impact. SMF and GMF probably affect baroreceptor sensory transduction, modulating baroreceptor membranes' Ca2+ channel permeability. Bioelectromagnetics 23:531–541, 2002. © 2002 Wiley‐Liss, Inc.
Matrix metalloproteinases and collagen catabolism
Authors: Lauer‐Fields Janelle L. , Juska Darius , Fields Gregg B.
Published: October 2002

The matrix metalloproteinase (MMP)/matrixin family has been implicated in both normal tissue remodeling and a variety of diseases associated with abnormal turnover of extracellular matrix components. The mechanism by which MMPs catabolize collagen (collagenolysis) is still largely unknown. Substrate flexibility, MMP active sites, and MMP exosites all contribute to collagen degradation. It has recently been demonstrated that the ability to cleave a triple helix (triple‐helical peptidase activity) can be distinguished from the ability to cleave collagen (collagenolytic activity). This suggests that the ability to cleave a triple helix is not the limiting factor for collagenolytic activity—the ability to properly orient and potentially destabilize collagen is. For the MMP family, the catalytic domain can unwind and cleave a triple‐helical structure, while the C‐terminal hemopexin‐like domain appears to be responsible for properly orienting collagen and destabilizing it to some degree. It is also possible that exosites within the catalytic and/or C‐terminal hemopexin‐like domain may exclude some MMPs from cleaving collagen. Overall, it appears that many proteases of distinct mechanisms possess triple‐helical peptidase activity, and that convergent evolution led to a few proteases possessing collagenolytic activity. Proper orientation and distortion of the triple helix may be the key factor for collagenolysis. © 2002 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 66: 19–32, 2002
Novel electrochemical–enzymatic model which quantifies the effect of the solution Eh on the kinetics of ferrous iron oxidation with Acidithiobacillus ferrooxidans
Authors: Meruane G. , Salhe C. , Wiertz J. , Vargas T.
Published: October 2002

The influence of solution Eh on the rate of ferrous iron oxidation by Acidithiobacillus ferrooxidans is characterized. The experimental approach was based on the use of a two‐chamber bioelectrochemical cell, which can determine the ferrous iron oxidation rate at controlled potential. Results enabled the formulation of a novel kinetic model, which incorporates the effect of solution Eh in an explicit form but still integrates the effect of ferrous iron concentration and ferric inhibition. The results showed that at Eh values below 650 mV (standard hydrogen electrode, SHE) the bacterial oxidative activity is mainly dependent on ferrous iron concentration. At Eh values between 650 and 820 mV (SHE) the oxidation rate is mainly controlled by ferric inhibition. Over 820 mV (SHE) the bacterial oxidative activity is strongly inhibited by the Eh increase, being completely inhibited at Eh = 840 mV (SHE). © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 80: 280–288, 2002.
Green marketing, public policy and managerial strategies
Authors: Prakash Aseem
Published: October 2002

Green marketing subsumes greening products as well as greening firms. In addition to manipulating the 4Ps (product, price, place and promotion) of the traditional marketing mix, it requires a careful understanding of public policy processes. This paper focuses primarily on promoting products by employing claims about their environmental attributes or about firms that manufacture and/or sell them. Secondarily, it focuses on product and pricing issues. Drawing on multiple literatures, it examines issues such as what needs to be greened (products, systems or processes), why consumers purchase/do not purchase green products and how firms should think about information disclosure strategies on environmental claims. Copyright © 2002 John Wiley & Sons, Ltd and ERP Environment.
The Sustainability Balanced Scorecard – linking sustainability management to business strategy
Authors: Figge Frank , Hahn Tobias , Schaltegger Stefan , Wagner Marcus
Published: October 2002

The Balanced Scorecard of Kaplan and Norton is a management tool that supports the successful implementation of corporate strategies. It has been discussed and considered widely in both practice and research. By linking operational and non‐financial corporate activities with causal chains to the firm's long‐term strategy, the Balanced Scorecard supports the alignment and management of all corporate activities according to their strategic relevance. The Balanced Scorecard makes it possible to take into account non‐monetary strategic success factors that significantly impact the economic success of a business. The Balanced Scorecard is thus a promising starting‐point to also incorporate environmental and social aspects into the main management system of a firm. Sustainability management with the Balanced Scorecard helps to overcome the shortcomings of conventional approaches to environmental and social management systems by integrating the three pillars of sustainability into a single and overarching strategic management tool. After a brief discussion of the different possible forms of a Sustainability Balanced Scorecard the article takes a closer look at the process and steps of formulating a Sustainability Balanced Scorecard for a business unit. Before doing so, the basic conventional approach of the Balanced Scorecard and its suitability for sustainability management will be outlined in brief. Copyright © 2002 John Wiley & Sons, Ltd and ERP Environment.
Processes of appraisal and coping in the development and maintenance of Premenstrual Dysphoric Disorder
Authors: Ussher Jane M.
Published: October 2002

This article examines the role of appraisal and coping strategies in relation to women's subjective negotiation of premenstrual changes, drawing on a series of narrative interviews conducted with women who met diagnostic criteria for Premenstrual Dysphoric Disorder (PMDD). The major themes that emerged from the interviews were: the PMDD sufferer as split; over‐responsibility is linked to PMDD; PMDD = lack of control; methods of coping; attributions for symptoms; and PMDD as a relational issue. This article draws on each of these narrative themes, in order to illustrate three interrelated psychological processes of appraisal and coping central to the development and maintenance of ‘PMDD’ or ‘PMS’ (Premenstrual Syndrome). The first process is awareness of changes in psychological or physical experiences, ability to cope, or reactivity to others, premenstrually. The second process involves expectations and perceptions of premenstrual changes. The third is women's response and ways of coping. This study thus stands in contrast to research positioned within a positivist epistemological framework, where PMDD is viewed as a fixed entity; and women's subjective experience of premenstrual changes, is marginalized or negated. It is argued that premenstrual changes evolve in the context of an ongoing interaction between internal experiences, perceptions, reactions, relationships, and cultural expectations, that differ between women, across menstrual cycles, and can shift within a specific cycle: described as a material‐discursive‐intrapsychic interaction. Copyright © 2002 John Wiley & Sons, Ltd.
Nonneutropenic febrile episodes associated with docetaxel‐based chemotherapy in patients with solid tumors
Authors: Souglakos John , Kotsakis Athanaslos , Kouroussis Charalambos , Kakolyris Stylianos , Mavroudis Dimitrios , Kalbakis Konstadinos , Agelaki Sofia , Vlachonikolis John , Georgoulias Vassilis , Samonis George
Published: October 2002

BACKGROUND

Docetaxel is associated with severe lymphopenia and increased incidence of nonneutropenic infection. This study investigated the incidence of nonneutropenic infections and/or febrile episodes in patients with solid tumors receiving frontline docetaxel‐based chemotherapy.

METHODS

Chemotherapy‐naive patients with solid tumors treated with docetaxel‐based chemotherapy were studied prospectively for the development of nonneutropenic infections.

RESULTS

During a 2‐year period, 680 cancer patients enrolled in 24 protocols received 2867 cycles of docetaxel‐containing chemotherapy. Fifty‐three patients (7.8%) developed nonneutropenic infections and/or febrile episodes. The most common of these were pulmonary infections (n = 25), Pneumocystis carinii interstitial pneumonias (n = 5), and candidal (n =11), herpetic (n =4), and cytomegaloviral (n =3) infections. Thirty‐six patients (68%) had severe lymphopenia (< 900 cells per deciliter) and 49 (92%) had less than 400 CD4+ cells per deciliter. Patients with a low CD4+ cell count (≤ 200 cells per deciliter) had a significantly higher probability to develop opportunistic than common infections (P = 0.002). The incidence of nonneutropenic infections and/or febrile episodes was significantly higher in patients treated with docetaxel/gemcitabine (18.3%; P = 0.0001) and docetaxel/CDDP (11.7%; P = 0.012) than in those treated with docetaxel alone (3.6%). Conversely, 175 patients who received 752 cycles of chemotherapy with paclitaxel‐containing regimens and 410 patients who received 2174 cycles with nontaxane‐based regimens developed 6 (3.4%; p=0.042) and 12 (3%; p=0.001) nonneutropenic infections, respectively. Less than 10% of the patients of the two latter groups were lymphopenic. The risk of nonneutropenic infection in patients receiving docetaxel‐based chemotherapy was 2.38 and 2.8 times higher than in patients receiving paclitaxel and nontaxane‐based chemotherapy, respectively.

CONCLUSIONS

Patients treated with docetaxel‐based chemotherapy are at increased risk of developing nonneutropenic infections. This may be related, at least partly, to severe postchemotherapy CD4+ lymphopenia. Cancer 2002;95:1326–33. © 2002 American Cancer Society.

DOI 10.1002/cncr.10802
Prospective randomized study of four novel chemotherapy regimens in patients with advanced nonsmall cell lung carcinoma
Authors: Greco F. Anthony , Gray James R. , Thompson Dana S. , Burris Howard A. , Erland Joan B. , Barton John H. , Litchy Sharlene , Houston Gerry A. , Butts James A. , Webb Charles , Scott Charles , Hainsworth John D.
Published: October 2002

BACKGROUND

The authors compared the toxicity, response rate, and progression free survival of four chemotherapy regimens for patients with advanced (Stage IIIB and IV) nonsmall cell lung carcinoma.

METHODS

A total of 267 patients entered this randomized Phase II trial on one of four arms: paclitaxel, carboplatin, and gemcitabine (Arm A); paclitaxel, carboplatin, and vinorelbine (Arm B); paclitaxel and gemcitabine (Arm C); and gemcitabine and vinorelbine (Arm D). Patient characteristics were similar in all treatment arms. At the time of tumor progression, patients were removed from study and were treated at the discretion of their physician.

RESULTS

Patients received a median of four courses of chemotherapy in all arms, and there was no difference in the dose delivered. There were no statistical differences in response rates (range, 32–45%), median progression free survival (range, 4.9–6.6 months), or progression free survival at 1 year (range, 8–19%). Actuarial survival in all four arms was not different, with a median survival ranging from 8.7 months to 10.7 months and a 1‐year survival rate of 38–44%. Each arm was compared with a historic control with a median survival of 8 months. Arm D (gemcitabine and vinorelbine) approached significance at the 0.05 level.

CONCLUSIONS

Two‐drug combinations containing the newer drugs without a platinum drug were less toxic than three‐drug, platinum‐based regimens. There were no significant differences in objective response rates or progression free survival when the four regimens were compared. The two‐drug combination of gemcitabine and vinorelbine was the least toxic and, thus, may be superior. A Phase III trial comparing combined gemcitabine and vinorelbine with combined paclitaxel, carboplatin, and gemcitabine is ongoing. Cancer 2002;95:1279–85. © 2002 American Cancer Society.

DOI 10.1002/cncr.10810
Pretreatment cognitive performance predicts survival in patients with leptomeningeal disease
Authors: Sherman Audrey M. , Jaeckle Kurt , Meyers Christina A.
Published: October 2002

BACKGROUND

Leptomeningeal disease (LMD) involves the spread of malignant cells from solid tumors to the cerebrospinal fluid or to the leptomeninges. LMD has a very poor prognosis and it is difficult to diagnose and follow with traditional diagnostic tools. The purposes of this study were to characterize cognitive functioning of LMD patients before treatment and to determine if measurement of cognitive functioning could be used to predict survival time.

METHODS

Thirty‐seven subjects with LMD were administered the Mattis Dementia Rating Scale (DRS) before they received treatment and statistical analyses were performed.

RESULTS

The Conceptualization subtest of the DRS was the most sensitive to disease course. It was the only individual subtest to predict survival and it was the most impaired subtest across individual subjects. These results support earlier findings of a frontal‐subcortical pattern of dysfunction in LMD patients. Cognitive performance at time of LMD diagnosis predicts survival time. Age and clinical status, two factors often correlated with survival in the cancer literature, did not predict survival time for our LMD population. In addition, there were no correlations between survival time and previous medical history or demographic factors.

CONCLUSIONS

Neuropsychological assessment appears to be a valuable tool both for tracking disease course over time and for predicting survival of patients. Cancer 2002;95:1311–6. © 2002 American Cancer Society.

DOI 10.1002/cncr.10816
Expression of endothelial and inducible nitric oxide synthase in benign and malignant lesions of the breast and measurement of nitric oxide using electron paramagnetic resonance spectroscopy
Authors: Loibl Sibylle , von Minckwitz Gunter , Weber Sonja , Sinn Hans‐Peter , Schini‐Kerth Valérie B. , Lobysheva Irina , Nepveu Françoise , Wolf Georg , Strebhardt Klaus , Kaufmann Manfred
Published: October 2002

BACKGROUND

Nitric oxide (NO) is present in various human solid tumors and tumor cell lines, and it is believed that NO plays an important role in tumor growth. An increased NO concentration catalyzed by NO synthase (NOS) is cytotoxic and can promote apoptosis. The expression of endothelial NOS (e‐NOS) and induced NOS (i‐NOS) was examined in various breast tumors.

METHODS

Immunohistochemical staining with a monoclonal antibody (Ab) against e‐NOS and a polyclonal Ab against i‐NOS was performed on paraffin embedded tissues from 41 benign breast lesions, 9 in situ breast lesions, and 54 invasive breast lesions. Functionality was confirmed by detection of NO using spin‐trapping electron paramagnetic resonance (EPR) spectroscopy.

RESULTS

e‐NOS expression was found in 2 benign lesions (5%; 1 fibroadenoma and 1 proliferative mastopathy), in 5 in situ lesions (56%), and in 33 invasive lesions (61%). None of the benign lesions was positive for i‐NOS, but 6 in situ lesions (67%) and 33 invasive lesions (61%) showed tumor cell staining. In particular, capillaries that were embedded in lymphocytic stroma showed a positive reaction for e‐NOS. The functionality of NOS was demonstrated by direct NO formation using the EPR spin‐trapping method. Tumors that were positive for e‐NOS were observed more often in younger patients (P = 0.05). These tumors more frequently were highly differentiated or moderately differentiated and more often showed invasive ductal subtypes and a lower proliferation rate. Tumors that were positive for both e‐NOS and i‐NOS were more likely to be lymph node negative tumors. Both i‐NOS‐expressing lesions and e‐NOS‐expressing lesions showed strong coexpression (P = 0.00001).

CONCLUSIONS

NOS is detected predominantly in in situ lesions and invasive breast lesions but rarely in benign lesions. NOS is found more frequently in invasive carcinomas with low malignancy. Using the spin‐trapping EPR method, this study demonstrates direct NO formation in human breast tumors for the first time. Cancer 2002;95:1191–8. © 2002 American Cancer Society.

DOI 10.1002/cncr.10817
Tissue microarray analysis of cytoskeletal actin‐associated biomarkers gelsolin and E‐cadherin in urothelial carcinoma
Authors: Rao JianYu , Seligson David , Visapaa Harri , Horvath Steve , Eeva Mervi , Michel Kia , Pantuck Allan , Belldegrun Arie , Palotie Aarno
Published: October 2002

BACKGROUND

Alterations of expression of the cytoskeletal proteins Gelsolin and E‐cadherin have been implicated in urothelial carcinoma tumorigenesis. However, it is not clear how these altered expressions associate with tumor progression, nor is it clear how these protein markers provide prognostic value for urothelial carcinomas.

METHODS

Primary urothelial carcinoma tissue microarrays were constructed for 146 patients with urothelial carcinoma. Where available, four replicate tissue samples of invasive tumor, adjacent dysplastic and in situ lesions, and benign tumors were arrayed for each case, resulting in a total of 1208 tissue spots. Immunohistochemical staining for Gelsolin, E‐cadherin, p53, and Ki67 (MIB‐1) was performed on the arrays. For each marker, the maximum staining intensity (Max), the percentage of positive staining (Pos), and the product of both Max and Pos (MaxPos) were analyzed.

RESULTS

Compared with the benign fields, the expression of both cytoskeletal proteins decreased in premalignant and malignant lesions. For Gelsolin, decreased MaxPos was seen in premalignant and preinvasive lesions. However, with an increase in tumor grade and stage, there was a gradual increase in Gelsolin (P < 0.05 for both). E‐cadherin expression decreases mainly in high‐grade lesions (carcinoma in situ and Grade 3 tumors). Univariate and multivariate analyses showed that Gelsolin Max was a strong independent predictor for the probability of tumor recurrence and for early tumor recurrence in high‐grade or high‐stage tumors, as well as a strong indicator for tumor progression.

CONCLUSIONS

Gelsolin and E‐cadherin have distinctive expression patterns. Gelsolin, but not E‐cadherin, provides independent prognostic information for high‐grade urothelial carcinomas. Cancer 2002;95:1247–57. © 2002 American Cancer Society.

DOI 10.1002/cncr.10823
In vivo modulation of a cortical functional sensory representation shortly after topical cholinergic agent application
Authors: Penschuck Silke , Chen‐Bee Cynthia H. , Prakash Neal , Frostig Ron D.
Published: October 2002

The aim of the present study was to determine whether cholinergic increase in the size of a functional representation (collective evoked response from a large population of neurons) can be observed shortly (within an hour) after treatment onset and whether nicotinic receptors can participate in this type of modulation. Cholinergic agonist application has been found previously to increase the response of a single cortical neuron to a stimulus. Also, pairing cholinergic basal forebrain stimulation with delivery of a tone has been reported to increase the size of that tone's functional representation. Whereas the increase in a single cortical neuron response can occur within seconds after cholinergic agonist application, to date the increase in the size of a functional representation has only been investigated within one to several weeks after the onset of pairing basal forebrain stimulation with tone delivery. Furthermore, primarily muscarinic receptors have been implicated in these types of changes in cortical activity. By using optical imaging of intrinsic signals in vivo, we found that the size of a whisker's functional representation in the primary somatosensory cortex of the rat increases substantially within 69 or 46 minutes after topical application of either a muscarinic or nicotinic agonist to the exposed cortex, respectively, and decreases within 23 minutes after topical application of a muscarinic antagonist. For each cholinergic agent, we verified that delivery of a cholinergic agent by means of topical application can lead to the agent's successful penetration through the cortical layers in the time allotted to complete an imaging experiment. Furthermore, the time course of penetration for each agent was characterized. Based on the combined imaging/penetration results, we speculate on potential sites of cholinergic action in the cortex. Irrespective of the exact mechanism of action, we demonstrate here that an increase in the size of a functional sensory representation can occur shortly by means of activation of either nicotinic or muscarinic receptors. J. Comp. Neurol. 452:38–50, 2002. © 2002 Wiley‐Liss, Inc.
A note on the equivalence of two recent time‐integration schemes for N‐body problems
Authors: Graham E. , Jelenić G. , Crisfield M. A.
Published: October 2002

This paper investigates the relationship between the energy‐ and momentum‐conserving time‐integration scheme of Simo and Gonzalez (Papers—American Society of Mechanical Engineers—All Series, 1993; 93(4)) and a momentum‐conserving time‐integration scheme due to Betsch and Steinmann (Int. J. Numer. Meth. Engng 2000; 49: 599) for N‐body problems. The schemes are shown to be identical if the potential energy of interaction between masses is a polynomial function of the distances between the masses, of degree two or lower. In addition, they are shown to recover the same relative equilibria. Copyright © 2002 John Wiley & Sons, Ltd.
Application of triangular differential quadrature to problems with curved boundaries
Authors: Zhong Hongzhi
Published: October 2002

The recently proposed concept of triangular differential quadrature is consolidated and extended to curvilinear triangles. First, a unit isosceles right triangle is taken as a standard triangle on which all derivatives are expressed in accordance with the triangular differential quadrature rule. Geometric transformations in which the basis functions for determination of weighting coefficients in the triangular differential quadrature are employed to map an arbitrary curvilinear triangle onto the standard triangle are introduced. A simple example is provided to validate the present strategy. Copyright © 2002 John Wiley & Sons, Ltd.
Novel stability criteria for bidirectional associative memory neural networks with time delays
Authors: Liao Xiaofeng , Yu Juebang , Chen Guanrong
Published: October 2002

In this paper, the bidirectional associative memory (BAM) neural network with axonal signal transmission delay is considered. This model is also referred to as a delayed dynamic BAM model. By combining a number of different Lyapunov functionals with the Razumikhin technique, some sufficient conditions for the existence of a unique equilibrium and global asymptotic stability of the network are derived. These results are fairly general and can be easily verified. Besides, the approach for the analysis allows one to consider several different types of activation functions, including piecewise linear sigmoids with bounded activations as well as C1‐smooth sigmoids. It is believed that these results are significant and convenient in the design and applications of BAM neural networks. Copyright © 2002 John Wiley & Sons, Ltd.
EVA: a better TCP version for resource‐insufficient networks
Authors: Li Jung‐Shian , Ma Chung‐Wen
Published: October 2002

TCP Vegas exhibits unfair congestion avoidance mechanism, which aggravates when there are insufficient network resources to accommodate buffer space of a pipe (bandwidth delay product). To remedy this shortcoming, we propose an Enhanced VegAs (EVA) that employs three auxiliary mechanisms: Δ revision, congestion detection and congestion tendency detection. A 2kfactorial design with replications is used to study the effect of the three mechanisms. Our results show that TCP EVA achieves better performance than Vegas under various network conditions. Furthermore, congestion avoidance schemes, such as TCP EVA, perform much better than congestion control schemes, such as TCP Reno, in resource‐insufficient networks. Copyright © 2002 John Wiley & Sons, Ltd.
Standard measures of executive function in predicting instrumental activities of daily living in older adults
Authors: Bell‐McGinty Sandra , Podell Kenneth , Franzen Michael , Baird Anne D. , Williams Michael J.
Published: October 2002

Objective

The purpose of this study was to examine the ability of specific, commonly used neuropsychological tests of executive function to predict functional status among a group of elderly subjects.

Methods

Fifty study participants underwent a brief neuropsychological evaluation of executive functions and assessment of instrumental activities of daily living (IADL).

Results

A multiple stepwise regression analysis indicated that executive function tests accounted for 54% of the variance in functional status. An examination of the standardized regression coefficients revealed that Trail Making Test‐Part B and the Wisconsin Card Sorting Test were the only two of the five executive function tests that significantly predicted functional status. These executive function measures contributed significantly to the prediction of functional status even after statistically controlling for age, sex, and education.

Conclusion

Thus, the common clinical measures of executive function are useful in predicting functional status in older adults. Copyright © 2002 John Wiley & Sons, Ltd.
Psychotropics among the home‐dwelling elderly—increasing trends
Authors: Linjakumpu T. , Hartikainen S. , Klaukka T. , Koponen H. , Kivelä S.‐L. , Isoaho R.
Published: October 2002

Objective

To assess the level of and changes in the use of psychotropics among the home‐dwelling elderly in the 1990s.

Methods

A descriptive analysis based on data from two cross‐sectional interview and health examination surveys of elderly persons aged 64 years or over conducted in Lieto, a typical semi‐rural Finnish municipality, in 1990–91 and 1998–99. National prescription data were utilized to compare the use of psychotropics in the late 1990s by all Finnish home‐dwelling elderly and the elderly in Lieto. In Lieto drug information was obtained from 1131 persons in 1990–91 and from 1197 in 1998–99, and the mean age of the informants was 73 years in both surveys. The brand names of the prescription drugs (both irregular and regular medication) taken by each interviewee during seven days prior to the interview were recorded and categorized by the Anatomical Therapeutic Chemical (ATC) classification system.

Results

Every fourth person was taking at least one psychotropic drug in both surveys. Most users were on regular psychotropic medication. The use of hypnotics and antidepressants increased most during the study period. Polypharmacy and the use of psychotropics were most prevalent among those aged 85 years or over, with women predominating. Concomitant use of two or more psychotropics increased statistically significantly from 7% to 10% between the surveys. The young elderly, aged 64–71 years, used cyclic antidepressants equally commonly in both surveys. None of the young elderly used new atypical antipsychotics in 1998–99.

Conclusions

Psychotropics tend to be overprescribed and overused among the elderly, a group at the highest risk of adverse drug reactions. The tendency of prescribing for the elderly is not going in a better direction. New‐generation psychotropics were not used. The need for long‐standing use of psychotropics should be assessed regularly. Copyright © 2002 John Wiley & Sons, Ltd.
Cognitive science and the work of reform
Authors: Halpern Diane F.
Published: October 2002

If academic leaders are serious about enhancing student learning, then what we are learning about how people learn from research in cognitive science must guide the redesign of higher education.
Effective assessment and institutional change
Authors: Brooks Cote Christine , Jordan Marianne
Published: October 2002

Assessment can result in a better match between educational goals and student involvement in achieving them.
Learning and teaching centers: Hubs of educational reform
Authors: Singer Susan R.
Published: October 2002

Learning and teaching centers serve as repositories of institutional memory and catalysts of campus conversations about critical educational issues.
The people and process of investing in facilities
Authors: Boylan Elizabeth S.
Published: October 2002

How people are drawn into and engaged with the process of planning new facilities for science has a direct relationship with the quality and character of the spaces that emerge from that effort.
Nutrition and pharyngeal cancer: Results from a case‐control study in Spain
Authors: Uzcudun Ana Escribano , Retolaza Iñaki Rabanal , Fernández Pilar Bravo , Sánchez Hernández José Javier , Grande Antonio García , García Alfredo García , Olivar Lara Miralles , de Diego Sastre Ignacio , Barón Manuel González , Bouzas José Gavilán
Published: October 2002

Background

Oropharyngeal and hypopharyngeal cancer is increasing all over the world, frequently affecting more and more women and younger individuals and not only the typical 50‐ to 60‐year‐old heavy smoker and drinking man. In addition, 5‐year overall survival rate remains poor (30% to 40% in most series), despite advances in treatment. Therefore, it is crucial to understand as accurately as possible the risk factors for these malignancies to improve primary prevention.

Methods

We report the results from a case‐control study of pharyngeal cancer risk factors conducted in Spain involving 232 consecutive patients who were gender‐ and age‐matched with 232 controls. Data were collected by interviewer‐administered personal interview.

Results

Our results show that low intake of fruit, fruit juice, uncooked vegetables, dietary fiber–containing foods (legume and cereals), fish, milk, and dairy products is an independent risk factor for pharyngeal cancer and that high consumption of meat and fried foods also increases the risk once data are adjusted for tobacco smoking and alcohol drinking.

Conclusions

Although findings for fruit, juice, and uncooked vegetables are in accordance with those from other authors and can be explained on a biologic basis, the relationship between pharyngeal cancer and dietary excess of saturated fatty acids needs experimental investigation. Findings for milk, dairy products, and fish also warrant more detailed epidemiologic research because of conflicting data reported in the literature and because of the reportedly ambiguous role of retinol in human cancers. No conclusive explanations for the protective effect of dietary fiber–containing foods can be put forward today. Our results are uniquely attributable to oropharyngeal and hypopharyngeal cancers because of the small size of our nasopharyngeal cancer subsample. © 2002 Wiley Periodicals, Inc. Head Neck 24: 830–840, 2002
Lipopolysaccharide‐induced metastatic growth is associated with increased angiogenesis, vascular permeability and tumor cell invasion
Authors: Harmey Judith H. , Bucana Corazon D. , Lu Weixin , Byrne Anne Marie , McDonnell Susan , Lynch Conor , Bouchier‐Hayes David , Dong Zhongyun
Published: October 2002

Endotoxin/lipopolysaccharide (LPS), a cell wall component of Gram‐negative bacteria, is a potent inflammatory stimulus. We previously reported that LPS increased the growth of experimental metastases in a murine tumor model. Here, we examined the effect of LPS exposure on key determinants of metastasis—angiogenesis, tumor cell invasion, vascular permeability, nitric oxide synthase (NOS) and matrix metalloproteinase 2 (MMP2) expression. BALB/c mice bearing 4T1 lung metastases were given an intraperitoneal (i.p.) injection of 10 μg LPS or saline. LPS exposure resulted in increased lung weight and incidence of pleural lesions. LPS increased angiogenesis both in vivo and in vitro. Vascular permeability in lung tissue was increased 18 hr after LPS injection. LPS increased inducible nitric oxide synthase (iNOS) and MMP2 expression in lung tumor nodules. 4T1 cells transfected with green fluorescent protein (4T1‐GFP) were injected via lateral tail vein. LPS exposure resulted in increased numbers of 4T1‐GFP cells in mouse lung tissue compared to saline controls, an effect blocked by the competitive NOS inhibitor, NG methyl‐L‐arginine (NMA). LPS‐induced growth and metastasis of 4T1 experimental lung metastases is associated with increased angiogenesis, vascular permeability and tumor cell invasion/migration with iNOS expression implicated in LPS‐induced metastasis. © 2002 Wiley‐Liss, Inc.
A population‐based prospective study of Chlamydia trachomatis infection and cervical carcinoma
Authors: Wallin Keng‐Ling , Wiklund Fredrik , Luostarinen Tapio , Ångström Tord , Anttila Tarja , Bergman Frank , Hallmans Göran , Ikäheimo Irma , Koskela Pentti , Lehtinen Matti , Stendahl Ulf , Paavonen Jorma , Dillner Joakim
Published: October 2002

Persistent human papillomavirus (HPV) infection is an established cause of cervical cancer, but the role of other sexually transmitted agents, most notably Chlamydia trachomatis, has not been well defined. The women participating in the population‐based cervical cancer screening program in Västerbotten county of Northern Sweden were followed up for up to 26 years to identify 118 women who developed cervical cancer after having had a normal Pap smear (on average 5.6 years later; range 0.5 months–26 years). As controls, we selected another 118 women who were matched by birth cohort, time‐point of sampling of the baseline normal smear and who had a normal smear at the time when the corresponding case was diagnosed with cancer. The Pap smears and cervical cancer biopsies were analyzed by PCR for C. trachomatis DNA and for HPV DNA. At baseline, C. trachomatis DNA was present in 8% of cases but not among any one of the controls. The relative risk for cervical cancer associated with past C. trachomatis infection, adjusted for concomitant HPV DNA positivity, was 17.1 (95% CI 2.6–∞).The presence of C. trachomatis and of HPV were not interrelated. Whereas C. trachomatis was primarily found in specimens taken many years before cancer diagnosis, HPV DNA was associated with a short lag time before cancer diagnosis. Whereas most women who were HPV DNA‐positive in the prediagnostic smear were also positive for the same virus in the cervical cancer biopsy, none of the women were positive for C. trachomatis in both the prediagnostic smear and in the subsequent cervical cancer. In conclusion, a prior cervical C. trachomatis infection was associated with an increased risk for development of invasive cervical cancer. © 2002 Wiley‐Liss, Inc.
In vivo evaluation of 188Re‐labeled alpha‐melanocyte stimulating hormone peptide analogs for melanoma therapy
Authors: Miao Yubin , Owen Nellie K. , Whitener Donna , Gallazzi Fabio , Hoffman Timothy J. , Quinn Thomas P.
Published: October 2002

The purpose of our study was to optimize melanoma tumor uptake of 188Re‐CCMSH and reduce its nonspecific kidney retention. Nephrotoxicity is often a serious problem associated with targeted radiotherapy, therefore, increasing the tumor/kidney uptake ratio of 188Re‐CCMSH is crucial for optimizing its therapeutic efficacy. Structural modification of the peptide and amino acid co‐infusion were investigated as strategies to improve the tumor/kidney uptake ratio of 188Re‐CCMSH. The substitution of Lys11 with Arg11 was examined to determine if removal of lysine from the peptide would improve kidney clearance without sacrificing tumor uptake. The pharmacokinetics of 188Re‐CCMSH and 188Re‐(Arg11)CCMSH were determined in B16/F1 murine melanoma‐bearing C57 mice. Tumor uptake values of 188Re‐CCMSH and 188Re‐(Arg11)CCMSH were 15.03 ± 5.20% ID/g and 20.44 ± 1.91% ID/g at 1 hr postinjection and 1.94 ± 0.47% ID/g and 3.50 ± 2.32% ID/g at 24 hr postinjection. Renal retention of 188Re‐(Arg11)CCMSH was 11.79 ± 1.29 ID/g and 3.67 ± 0.51 ID/g at 1 hr and 4 hr postinjection, which was a greater than 50% reduction compared to 188Re‐CCMSH. The Arg for Lys substitution in 188Re‐(Arg11)CCMSH resulted in improved tumor uptake and reduced kidney retention. Renal retention of both 188Re‐CCMSH and 188Re‐(Arg11)CCMSH were significantly reduced by co‐injection of 20 mg of L‐lysine, L‐arginine and a combination of L‐lysine:L‐arginine. Tumor/kidney uptake values for 188Re‐CCMSH and 188Re‐(Arg11)CCMSH were maximally reduced by 52.9% and 46.3%, respectively. However, even with amino acid co‐injection, the tumor/kidney ratio of 188Re‐CCMSH was lower than that of 188Re‐(Arg11)CCMSH. Improved tumor uptake and reduced kidney retention of 188Re‐(Arg11)CCMSH will facilitate targeted irradiation of melanoma tumors while minimizing the dose to the kidneys. © 2002 Wiley‐Liss, Inc.
Cell adhesion on poly(propylene fumarate‐co‐ethylene glycol) hydrogels
Authors: Tanahashi Kazuhiro , Mikos Antonios G.
Published: October 2002

We synthesized poly(propylene fumarate‐co‐ethylene glycol) block copolymers [P(PF‐co‐EG)] that were crosslinked to form hydrogels and investigated the effect of copolymer composition on cell adhesion to the hydrogels. These copolymers were water soluble when the molar ratio of ethylene glycol repeating unit to propylene fumarate repeating unit was higher than 4.4. The water content of swollen hydrogels increased from 29 to 63% and the water contact angle decreased from 38 to 21° as the molar ratio increased from 0.6 to 4.4. No significant change in either property was observed for ratios higher than 4.4. In a cell adhesion assay under serum‐free conditions, the number of adherent platelets and smooth muscle cells decreased from 21 to 2% and from 78 to 20% of the initial seeding density, respectively, as the molar ratio increased from 0.6 to 7.8. Adherent smooth muscle cells did not spread on the hydrogels of the compositions tested. Adherent platelets did not show any filopodia. These results suggest that the hydrophilicity of P(PF‐co‐EG) hydrogels is one of the factors affecting cell adhesion, and that copolymer modification may be required for enhancing cell adhesion for an application involving the copolymers as in situ crosslinkable cell carriers. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 62: 558–566, 2002
Introduction of the green fluorescent protein gene into hematopoietic stem cells results in prolonged discrepancy of in vivo transduction levels between bone marrow progenitors and peripheral blood cells in nonhuman primates
Authors: Hanazono Yutaka , Terao Keiji , Shibata Hiroaki , Nagashima Takeyuki , Ageyama Naohide , Asano Takayuki , Ueda Yasuji , Kato Ikunoshin , Kume Akihiro , Hasegawa Mamoru , Ozawa Keiya
Published: October 2002

Background

The green fluorescent protein (GFP) has proven a useful marker in retroviral gene transfer studies targeting hematopoietic stem cells (HSCs) in mice. However, several investigators have reported very low in vivo peripheral blood marking levels in nonhuman primates after transplantation of HSCs transduced with the GFP gene. We retrovirally marked cynomolgus monkey HSCs with the GFP gene, and tracked in vivo marking levels within both bone marrow progenitor cells and mature peripheral blood cells following autologous transplantation after myeloablative conditioning.

Methods

Bone marrow cells were harvested from three cynomolgus macaques and enriched for the primitive fraction by CD34 selection. CD34+ cells were transduced with one of three retroviral vectors all expressing the GFP gene and were infused after myeloablative total body irradiation (500 cGy × 2). Following transplantation, proviral levels and fluorescence were monitored among clonogenic bone marrow progenitors and mature peripheral blood cells.

Results

Although 13–37% of transduced cells contained the GFP provirus and 11–13% fluoresced ex vivo, both provirus and fluorescence became almost undetectable in the peripheral blood within several months after transplantation regardless of the vectors used. However, on sampling of bone marrow at multiple time points, significant fractions (5–10%) of clonogenic progenitors contained the provirus and fluoresced ex vivo reflecting a significant discrepancy between GFP gene marking levels within bone marrow cells and their mature peripheral blood progeny. The discrepancy (at least one log) persisted for more than 1 year after transplantation. Since no cytotoxic T lymphocytes against GFP were detected in the animals, an immune response against GFP is an unlikely explanation for the low levels of transduced peripheral blood cells. Administration of granulocyte colony stimulating factor and stem cell factor resulted in mobilization of transduced bone marrow cells detectable as mature granulocyte progeny which expressed the GFP gene, suggesting that transduced progenitor cells in bone marrow could be mobilized into the peripheral blood and differentiated into granulocytes.

Conclusions

Low levels of GFP‐transduced mature cells in the peripheral blood of nonhuman primates may reflect a block to differentiation associated with GFP; this block can be overcome in part by nonphysiological cytokine treatment ex vivo and in vivo. Copyright © 2002 John Wiley & Sons, Ltd.