bluuebunny/crossref_metadata_2025 huggingface dataset:
Revealing the chromophoric composition of multichromophoric polypyridyl complexes of Re(I) and Os(II): a resonance Raman study
Authors: Flood Amar , Girling Reuben B. , Gordon Keith C. , Hester Ronald E. , Moore John N. , Polson Matthew I. J.
Published: October 2002

Several binuclear Re(I) and Re(I)Os(II) complexes with polypyridyl bridging ligands, 6,7‐dimethyl‐2,3‐di(2‐pyridyl)quinoxaline (dpqMe2) and [2,3‐a:3′,2′‐c]dipyrido‐6,7‐dimethylphenazine (ppbMe2), were synthesized and studied. The visible region of the electronic absorption spectrum is dominated by a single metal‐to‐ligand charge‐transfer band (ca 600 nm) and a dpqMe2‐ or ppbMe2‐based ligand‐centred band (ca 400 nm). The resonance Raman spectra of these complexes were recorded at several excitation wavelengths. Analysis of the resonance Raman spectra identified a number of strongly enhanced chromophore‐specific signatures with excitation wavelengths coincident with the main absorption bands, and weakly enhanced chromophore‐specific signatures at intermediate excitation wavelengths. Resonance Raman excitation profiles (RREPs) are presented for selected marker bands. Analysis of the chromophore‐specific signatures and the RREPs allowed a more complete assignment of the features in the electronic absorption spectra to be made. Copyright © 2002 John Wiley & Sons, Ltd.
Polyphenoloxidase activity and total phenolic content as related to browning of minimally processed ‘Jonagored’ apple
Authors: Rocha Ada M C N , Morais Alcina M M B
Published: October 2002

Phenolic content, polyphenoloxidase (PPO) activity and browning have been reported by different authors to vary in different ways, depending on cultivar, picking maturity, storage conditions, etc. Numerous authors have attempted to correlate browning results with the phenolic content and/or enzymatic activity of apples, but data published in the literature are divergent as to which of the two factors, ie the enzyme or the substrate, plays the decisive role in the overall phenomenon of enzymatic browning. The aim of this work was to follow the PPO activity and phenolic content of minimally processed apple (cv ‘Jonagored’) during cold storage and to establish a potential relationship with enzymatic browning. Increasing storage time of minimally processed apple seemed to result in an increase in PPO activity. No changes (P > 0.05) in total phenolic content were observed during storage. Colour degradation of apple cubes, as indicated by changes in colour parameters, was found to be highly correlated with PPO activity. Browning of ‘Jonagored’ apple cubes during storage was found to be moderately correlated with PPO activity. No correlation was found between the browning index and the total phenolic content.

© 2001 Society of Chemical Industry
Effect of enzymatic hydrolysis of proteins on growth of Bifidobacterium bifidus in milk
Authors: Vijaya G V , Gireesh T , Bhat Gajanan S
Published: October 2002

The effect of enzymatic hydrolysis of proteins in milk using neutrase on the growth of the probiotic strain Bifidobacterium bifidus was evaluated by estimation of microbial growth, acidity, viscosity and flavour production. A significant increase in the growth of B bifidus was observed in neutrase‐hydrolysed milk. The setting time of bifidus‐cultured milk was advanced by about 12 h at 5% degree of hydrolysis. Enzymatic hydrolysis of proteins prior to cultivation also significantly increased the viscosity of the product. An approximately 60% increase in viscosity of the product was observed in neutrase‐hydrolysed milk. Production of steam‐volatile monocarbonyls as an indication of development of flavour was also higher in neutrase‐hydrolysed milk. The concentration of steam‐volatile monocarbonyls was 2.47 µmol per 100 ml in neutrase‐hydrolysed milk but only 1.84 µmol per 100 ml in control milk at the setting point of the curd.

© 2002 Society of Chemical Industry
Effect of glucose and glycine addition to cocoa mass before roasting on Maillard precursor consumption and pyrazine formation
Authors: de Brito Edy S , Narain Narendra , Pezoa García Nelson H , Valente Antonio L P , Pini Gláucia F
Published: October 2002

Cocoa mass was treated with glucose and/or glycine before roasting. For glucose‐treated samples the reductions in reducing sugars and free amino acids were 41.1 and 56.9% respectively, whereas for glycine‐treated samples the respective reductions were 16.2 and 37.4%. The combination of glucose plus glycine treatment led to 39.0 and 48.9% reductions in reducing sugars and free amino acids respectively. For free amino acids the reductions in control and glucose‐treated samples were similar, 56.2 and 56.9% respectively, indicating that the added glucose did not significantly (P < 0.05) influence the free amino acid uptake. When glycine was added, the consumption of free amino acids (37.4%) was lower than for the control and glucose treatments. When glucose and glycine were added, the reduction in free amino acids (48.9%) was lower than for the control and glucose treatments but higher than for the glycine treatment. Apparently, glycine addition inhibited the reducing sugar and free amino acid consumption, whereas glucose addition enhanced the reducing sugar and free amino acid consumption. The glucose plus glycine treatment was similar to the glycine treatment in the contents of 2,5‐dimethyl‐ and trimethylpyrazines. For 2‐methylpyrazine the value for glucose‐treated samples was lower than for control and glycine‐treated samples but almost equal to the value for the glucose plus glycine treatment. It is concluded that the addition of glucose and/or glycine does not affect pyrazine production.

© 2002 Society of Chemical Industry
In vitro fermentation of cereal dietary fibre carbohydrates by probiotic and intestinal bacteria
Authors: Crittenden Ross , Karppinen Sirpa , Ojanen Suvi , Tenkanen Maija , Fagerström Richard , Mättö Jaana , Saarela Maria , Mattila‐Sandholm Tiina , Poutanen Kaisa
Published: October 2002

A range of probiotic and other intestinal bacteria were examined for their ability to ferment the dietary fibre carbohydrates β‐glucan, xylan, xylo‐oligosaccharides (XOS) and arabinoxylan. β‐Glucan was fermented by Bacteroides spp and Clostridium beijerinckii but was not fermented by lactobacilli, bifidobacteria, enterococci or Escherichia coli. Unsubstituted xylan was not fermented by any of the probiotic bacteria examined. However, many Bifidobacterium species and Lactobacillus brevis were able to grow to high yields using XOS. XOS were also efficiently fermented by some Bacteroides isolates but not by E coli, enterococci, Clostridium difficile, Clostridium perfringens or by the majority of intestinal Lactobacillus species examined. Bifidobacterium longum strains were able to grow well using arabinoxylan as the sole carbon source. These organisms hydrolysed and fermented the arabinosyl residues from arabinoxylan but did not substantially utilise the xylan backbone of the polysaccharide. Arabinoxylan was not fermented by lactobacilli, enterococci, E coli, C perfringens or C difficile and has potential to be an applicable carbohydrate to complement probiotic Bif longum strains in synbiotic combinations.

© 2002 Society of Chemical Industry
Genetic differentiation between the clam species Ruditapes decussatus (grooved carpet shell) and Venerupis pullastra (pullet carpet shell) by PCR–SSCP analysis
Authors: Fernández Alicia , García Teresa , Asensio Luis , Rodríguez Miguel Ángel , González Isabel , Lobo Esther , Hernández Pablo E , Martín Rosario
Published: October 2002

Genetic differentiation of the clam species Ruditapes decussatus (grooved carpet shell) and Venerupis pullastra (pullet carpet shell) has been achieved based on polymerase chain reaction–single‐strand conformation polymorphism (PCR–SSCP) analysis. A short fragment (150 bp) of the α‐actin gene was amplified by PCR. Amplicons were denatured to obtain single‐stranded DNA, electrophoresed on a non‐denaturing polyacrylamide gel and visualised by silver staining for detection of SSCPs. Species‐specific DNA band patterns were obtained for R decussatus and V pullastra, allowing clear differentiation of the two clam species.

© 2002 Society of Chemical Industry
Browning in processed yams: peroxidase or polyphenol oxidase?
Authors: Chilaka Ferdinand C , Eze Sabinus , Anyadiegwu Clement , Uvere Peter O
Published: October 2002

Polyphenol oxidase and peroxidase were purified from white yam (Dioscorea rotundata) using DEAE‐cellulose ionexchange chromatography. Thermoinactivation curves for polyphenol oxidase showed monophasic kinetics, while those for peroxidase were biphasic. Urea partially stabilised peroxidase against irreversible thermoinactivation, but did not do so in the case of polyphenol oxidase. Only peroxidase was capable of regenerating activity after thermoinactivation. The results showed that thermoinactivation of peroxidase was mainly due to conformational changes, while that of polyphenol oxidase was probably due to covalent damage. Peroxidase reactivation might play an important role in the browning of processed yam.

© 2002 Society of Chemical Industry
Processing factors affecting the level of residual cyanohydrins in gari
Authors: Onabolu A O , Oluwole O S A , Rosling H , Bokanga M
Published: October 2002

Intake of cyanogens in gari, a food processed from cassava roots, is implicated in the causation of tropical ataxic neuropathy (TAN). This neurological syndrome is endemic in some communities in south‐western Nigeria. Studies have shown that methods of processing cassava roots determine the quantity of cyanogens in gari. This study was conducted to investigate the effects of the method of dewatering and the duration of fermentation on cyanogens in gari. Cassava roots (400 kg) were peeled, washed, grated and divided into 14 woven polyethylene sacks. The mash in seven of the sacks was dewatered continuously during fermentation, while the mash in the remaining seven sacks was fermented without dewatering, but dewatered at the end of fermentation. Cassava mash from each treatment was roasted into gari at 24 h intervals up to 168 h. Mean cyanohydrin content in gari roasted from cassava mash dewatered continuously during fermentation was 10.8 mg HCN eq kg−1 dw (CI 9.7–11.9), while mean cyanohydrin content in gari roasted from cassava mash dewatered after fermentation was 6.3 mg HCN eq kg−1 dw (CI 5.3–7.4). Mean linamarin content was 4.0 mg HCN eq kg−1 dw (CI 3.1–4.9) and mean HCN content was 1.6 mg kg−1 dw (CI 1.3–1.9) in gari roasted from cassava mash dewatered continuously, while mean linamarin content was 3.2 mg HCN eq kg−1 dw (CI 2.3–4.0) and mean HCN content was 1.2 mg kg−1 dw (CI 0.9–1.5) in gari roasted from cassava mash dewatered after fermentation. The method of dewatering cassava mash and the duration of fermentation were significantly associated with the level of cyanohydrin in gari (p < 0.001). This study shows that dewatering of cassava mash continuously during fermentation contributes to the dietary cyanide load in TAN‐affected communities.

© 2002 Society of Chemical Industry
The effect of feeding regimen on apparent and true ileal nitrogen digestibility for rats fed diets containing different sources of protein
Authors: James Kerry A C , Butts Christine A , Koolaard John P , Donaldson Helen E , Scott Margaret F , Moughan Paul J
Published: October 2002

A standard protocol is required for carrying out routine ileal nitrogen (N) digestibility rat bioassays. The aim of this study was to determine the effects of feeding regimen on ileal N digestibility in rats fed diets containing different protein sources and chromic oxide as an indigestible marker. The experimental design was seven diets (protein‐free (PF), enzyme‐hydrolysed casein (EHC), lactalbumin (LAC), wheat gluten (GLU), fish fillets (FIS), soy protein isolate (SOY), zein) by three feeding regimens (frequent, meal, ad libitum) with 10 rats per diet. In frequent feeding, food was provided for eight 10 min periods between 09:00 and 16:00; in meal feeding, food was provided for one 3 h period at 09:00; in ad libitum feeding, food was available at all times. Rats were fed for 8 days, killed and digesta were collected from the terminal 20 cm of the ileum. The diets and freeze‐dried digesta were then analysed for N and chromium (Cr). There were statistically significant effects of feeding regimen on ileal digesta weight, ileal N/Cr ratio and apparent (AND) and true (PF TND, EHC TND) N digestibility. Mean N digestibilities, averaged over four dietary treatments (LAC, GLU, FIS, SOY), for the frequent, meal and ad libitum feeding regimens respectively were: AND, 88.8, 90.4, 85.8; PF TND, 94.9, 96.4, 97.0; EHC TND, 92.7, 94.0, 95.6. Although the N digestibilities were higher for rats on meal feeding compared with frequent feeding, the only statistically significant differences were for the lactalbumin treatment, and these were small in absolute terms. This study demonstrated that meal feeding was suitable and frequent feeding was unnecessary for most protein sources tested, and that ad libitum feeding was not ideal because of the smaller and more variable quantities of digesta collected and the more variable ileal N/Cr ratios.

© 2002 Society of Chemical Industry
Effect of prebaking and frozen storage on the sensory quality and instrumental texture of bread
Authors: Fik Mirosław , Surówka Krzysztof
Published: October 2002

The effect of part‐baking, freezing, frozen storage, thawing and rebaking on the quality of bread has been investigated. Quality evaluation of the stored bread was done using sensory analysis, instrumental texture profile analysis (TPA) and cutting tests of the crumb and crust. It was found that frozen bread with 71% fraction of baking time showed high stability of sensory features and rheological parameters during the entire storage period (11 weeks) and, after thawing and rebaking, had superior quality in comparison with its frozen and thawed full‐baked (100%) counterpart. Second‐order regression showed that the optimal time for the initial prebaking lies within the wide range from 74 to 86% of the time needed for the full‐baking of unfrozen bread. It is therefore a good method for preventing the staling process and obtaining a product of a quality close to that of fresh, not frozen bread. It has also been shown that a fraction of baking time equal to 43% was too small to ensure desirable sensory and textural features of bread after its frozen storage and rebaking.

© 2002 Society of Chemical Industry
Comparative content of some phytochemicals in Spanish apples, peaches and pears
Authors: Gorinstein Shela , Martin‐Belloso Olga , Lojek Antonin , Číž Milan , Soliva‐Fortuny Robert , Park Yong‐Seo , Caspi Abraham , Libman Imanual , Trakhtenberg Simon
Published: October 2002

Dietary fibre, total polyphenols and phenolic acids in Spanish apples, peaches and pears were analysed and compared with their total radical‐trapping antioxidative potential (TRAP). There were no significant differences in the content of dietary fibre among the studied fruits. The content of total polyphenols was 2.4 ± 0.4, 2.1 ± 0.3 and 6.9 ± 0.7 g kg−1 in peeled fruits and 4.7 ± 0.4, 4.5 ± 0.4 and 11.1 ± 1.2 g kg−1 in their peels for peaches, pears and apples respectively. The contents of dietary fibre, total polyphenols, caffeic, p‐coumaric and ferulic acids and the TRAP values were significantly (P < 0.05) higher in peels than in peeled fruits. The contents of all studied compounds and the TRAP values were significantly higher in peeled apples and their peel than in peaches and pears. We observed a strong correlation between the contents of total polyphenols and phenolic acids and the total radical‐trapping antioxidative potential in all three fruits. The relatively high content of dietary fibre, the highest contents of total polyphenols, caffeic, p‐coumaric and ferulic acids and the highest value of TRAP make apples preferable among the studied fruits for dietary prevention of atherosclerosis and other diseases.

© 2002 Society of Chemical Industry
Evaluation of heat and oxidative damage during storage of processed tomato products. I. Study of heat damage indices
Authors: Giovanelli Gabriella , Lavelli Vera
Published: October 2002

The evolution of heat damage during storage of tomato pulp, puree and paste was studied by accelerated aging tests. Heat damage indices—5‐hydroxymethyl‐2‐furfural (HMF), furosine and colour changes (ΔE)—were evaluated for tomato products stored at 30, 40 and 50 °C for up to 90 days. Furosine and ΔE values increased following pseudo‐zero‐order kinetics, and the higher the solid content of the products, the higher were the rate constant values. HMF formation followed pseudo‐first‐order kinetics in tomato pulp and pseudo‐zero‐order kinetics in puree and paste samples. Data show that heat damage reactions in tomato products proceed even at room temperature, and the kinetic model provided can be used to predict changes occurring during shelf‐life.

© 2002 Society of Chemical Industry
Predictors of nodal metastasis in salivary gland cancer
Authors: Korkmaz Hakan , Yoo George H. , Du Wei , Hocwald Eitan , Otero‐Garcia Jose E. , Volkan Adsay N. , Shibuya Terry , Jacobs John R.
Published: October 2002

Objectives

This study was conducted to determine clinical and histologic factors that would predict nodal metastasis in patients with major salivary gland cancer.

Methods

A retrospective study of 40 patients who underwent surgery, including neck dissection, for major salivary gland cancer between 1975 and 1997 was performed. Patient charts were reviewed, and clinical and pathologic data were extracted along with outcome. Predictive factors were identified and survival curves were obtained.

Results

Neck dissections were performed in 40 patients, which revealed histologic evidence of tumor in lymph nodes in 15 cases. Histologically proven metastasis was found in 16% of specimens from elective and 73% of specimens from therapeutic neck dissection. Five‐year overall and locoregional disease‐free survival rates for histologically positive and negative groups were 40% versus 63% (P < 0.05) and 67% versus 69% (P = 0.59), respectively. Univariate analysis of the factors revealed that clinical evidence of nodal metastasis (P < 0.001) and high‐grade cancer (P < 0.033) predicted histologic nodal involvement. Multivariate analysis revealed that only a positive neck examination was a significant predictive factor (OR = 31, 95%CI = 2.99–312).

Conclusions

Our results suggest that clinical neck examination is a reliable predictor of regional metastasis in patients with major salivary gland cancer. In view of the low frequency of occult metastases, routine elective treatment of the neck is not recommended. J. Surg. Oncol. 2002;80:186–189. © 2002 Wiley–Liss, Inc.
The Singapore Gold Circle: Perceptions of local customers of travel agencies
Authors: Litvin Stephen W.
Published: October 2002

The Singapore Tourism Board has created an ambitious service quality programme, the Singapore Gold Circle (SGC), for the local tourism industry. To date, the Board has made the programme available to the retail, travel agent and tour operator, and spa sectors. This study looks at the SGC to determine, from a travel consumer perspective and with a focus on the travel agency sector, the value and effectiveness of the programme. In addition to the value of the findings to the local tourism community, if successful, such a programme may serve as a blueprint for other national tourism organisations or regional associations seeking to raise the quality of their product. Copyright © 2002 John Wiley & Sons, Ltd.
Gay men's holiday destination choice: a case of risk and avoidance
Authors: Hughes Howard
Published: October 2002

Gay men are subject to discrimination and social disapproval in many parts of the world. This paper examines the possible impact of this on choice of holiday destination, drawing on the concepts of risk and destination avoidance. A number of interviews were held with gay men and it was concluded that risk of adverse reactions and of the need to modify behaviour were significant issues in destination avoidance and choice. It is possible, as a consequence, to classify holiday‐taking by gay men into a typology including gay‐centric and gay‐related. In addition, it is appropriate to modify existing models of risk‐avoidance through the addition of the risks that are more applicable to gay men than to other tourists. Copyright © 2002 John Wiley & Sons, Ltd.
Aluminum inhibition of microglial function in vitro
Authors: He Bei Ping , Strong Michael J.
Published: October 2002

We have previously observed in vivo that chronic AlCl3 exposure in young adult New Zealand white rabbits induces a reversible motor neuron degeneration. In addition to the development of neurofilamentous aggregates within degenerating neurons, we have also observed a reduction of microglial number and activation. To determine if aluminum could directly effect microglial function in vivo, we used an immortalized murine microglial cell line (BV‐2) to study the effect of organic (aluminum lactate) and inorganic (AlCl3) compounds on microglial function. We have observed a dose‐dependent inhibition of phagocytosis, proliferation, migration, and release of TNF‐α and nitric oxide in the absence of inducing microglial death. Both organic and inorganic aluminum decreased the extent of LPS‐activated microglia‐mediated death of a motor neuron hybridoma cell line (NSC 34). These findings demonstrate that aluminum compounds can directly affect microglial in vitro. J. Trace Elem. Exp. Med. 15:141–152, 2002. © 2002 Wiley‐Liss, Inc.
Importance of cutaneous cooling during photothermal epilation: Theoretical and practical considerations
Authors: Klavuhn Kurt G. , Green David
Published: October 2002

Background and Objectives

Sapphire contact cooling is widely used to prevent non‐specific epidermal injury from occurring during selective laser treatment of unwanted hair and vascular lesions. This small study was performed to examine the clinical response of the skin to 800‐nm laser irradiation with varying extent of cutaneous sapphire contact cooling. Observed clinical responses are compared to those predicted by theoretical analysis in an attempt to construct a more complete picture of sapphire contact cooling and its role in preventing non‐targeted tissue devitalization during laser treatment of the skin using a wavelength, pulse duration, and radiant exposure commonly used for laser hair removal.

Study Design/Materials and Methods

Three subjects each received a total of three pulses of laser light (800 nm) of equal radiant exposure (60 J/cm2), pulse duration (30 msec), and spot size (9 mm × 9 mm), but with varying extent of cutaneous cooling. One site was pre‐cooled and heat‐sinked with a chilled (5°C) sapphire window in contact with the skin; another site was heat‐sinked only with a room‐temperature (20°C) sapphire window in contact with the skin; and a third site received no pre‐cooling or heat‐sinking. Each site was examined immediately after treatment and at intervals throughout a 3‐month period. The thermal response of the tissue was calculated in each case using a Monte Carlo model for light transport in multi‐layered tissues coupled with an axisymmetric finite‐difference heat diffusion model. Thermal injury was modeled as a first‐order kinetic rate process using an Arrhenius expression.

Results

In all three subjects, the sites that were pre‐cooled and heat‐sinked showed no evidence of epidermal or dermal devitalization. The three sites that were heat‐sinked only had a few patches of perifollicular epidermal devitalization and subsequent desquamation without any permanent epidermal or dermal injury, as would be evidenced by pigmentary alteration or textural change. In each subject, the site that received no pre‐cooling or heat‐sinking sustained epidermal and dermal devitalization, appearing as ulceration and resulting in sustained erythema and textural alteration. Clinical responses predicted by theoretical analysis agree with the clinical observations and show that the dominant effect of sapphire contact cooling for pulse durations of 30 msec or less is the reduction of fluence within the epidermis resulting from index matching at the skin surface.

Conclusions

The results of this small study suggest that by judiciously selecting the laser pulse duration and pre‐cooling and heat‐sinking the epidermis in a manner that provides index matching and compression of the skin, epidermal damage can be avoided while administering the highest, most effective radiant exposures. Lasers Surg. Med. 31:97–105, 2002. © 2002 Wiley‐Liss, Inc.
Language and advertising effectiveness: Mediating influences of comprehension and cognitive elaboration
Authors: Wyer Robert S.
Published: October 2002

Both memory for an advertisement and its impact on attitudes can be influenced by a number of linguistic factors, including the typeface in which the information is presented, familiarity with its semantic features, and syntactic complexity. In the case of bilinguals, more general differences may result from persons' facility with the language in which the information is conveyed. Many of these diverse effects seem likely to be mediated by the influence of linguistic variables both on the comprehension of the information and on the amount and type of cognitive elaboration of its implications. The present article presents a simplified conceptual framework within which these effects can be viewed. © 2002 Wiley Periodicals, Inc.
Mutation rate and specificity analysis of tetranucleotide microsatellite DNA alleles in somatic human cells
Authors: Eckert Kristin A. , Yan Guang , Hile Suzanne E.
Published: October 2002

We have systematically varied microsatellite sequence composition to determine the effects of repeat unit size, G+C content, and DNA secondary structure on microsatellite stability in human cells. The microsatellites were inserted in frame within the 5′ region of the herpes simplex virus thymidine kinase (HSV‐tk) gene. The polypyrimidine/polypurine microsatellites displayed enhanced S1 nuclease sensitivity in vitro, consistent with the formation of non–B‐form DNA structures. Microsatellite mutagenesis studies were performed with a shuttle vector system in which inactivating HSV‐tk mutations are measured after replication in a nontumorigenic cell line. A significant increase in the HSV‐tk mutation frequency per cell generation was observed after insertion of [TTCC/AAGG]9, [TTTC/AAAG]9, or [TCTA/AGAT]9 sequences (P ≤ 0.0002), relative to the HSV‐tk gene control. We observed that the G + C content of the microsatellite may affect mutagenesis, as the mean microsatellite mutation rates of the [TTTC/AAAG]9 and [TCTA/AGAT]9 alleles were sevenfold and 11‐fold higher, respectively, than the [TTCC/AAGG]9 allele. A bias toward expansion mutations was noted for the majority of clones bearing the [TTCC/AAGG]9 allele as well as a [TC/AG]17 microsatellite of similar allele length. The mean microsatellite mutation rate of the [TTCC/AAGG]9 allele did not differ significantly from that for a [TC/AG]11 allele, demonstrating that these tetranucleotide and dinucleotide alleles are of equivalent stability. It is known that microsatellite mutagenesis is affected by the number of repeat units within an allele. Our data suggest that additional biochemical factors may regulate both the rate and specificity of somatic cell microsatellite mutagenesis. © 2002 Wiley‐Liss, Inc.
Competitor identification and competitor analysis: a broad‐based managerial approach
Authors: Bergen Mark , Peteraf Margaret A.
Published: October 2002

Managerial myopia in identifying competitive threats is a well‐recognized phenomenon (Levitt, 1960; Zajac and Bazerman, 1991). Identifying such threats is particularly problematic, since they may arise from substitutability on the supply side as well as on the demand side. Managers who focus only on the product market arena in scanning their competitive environment may fail to notice threats that are developing due to the resources and latent capabilities of indirect or potential competitors. This paper brings together insights from the fields of strategic management and marketing to develop a simple but powerful set of tools for helping managers overcome this common problem. We present a two‐stage framework for competitor identification and analysis that brings into consideration a broad range of competitors, including potential competitors, substitutors, and indirect competitors. Specifically we draw from Peteraf and Bergen's (2001) framework for competitor identification to develop a hierarchy of competitor awareness. That is used, in combination with resource equivalence, to generate hypotheses on competitive analysis. This framework not only extends the ken of managers, but also facilitates an assessment of the strategic opportunities and threats that various competitors represent and allows managers to assess their significance in relative terms. Copyright © 2002 John Wiley & Sons, Ltd.
Why do gas prices vary, or towards understanding the micro‐structure of competition
Authors: Bromiley Philip , Papenhausen Chris , Borchert Patricia
Published: October 2002

Strategic management work on competition considers industry segments or industries for the most part. We argue that real competition occurs at much lower levels of aggregation in many industries: what we term the micro‐structure of competition. Micro‐structures arise from boundedly rational firms searching imperfectly for business opportunities and boundedly rational consumers searching in a behaviorally determined manner for products and services. This paper lays out the basics of the micro‐structural approach to competitive analysis and presents initial propositions from that approach. Copyright © 2002 John Wiley & Sons, Ltd.
The performance effects of unintended and purposive multimarket contact
Authors: Gimeno Javier
Published: October 2002

Multimarket contact may arise from unintended encounters among competitors pursuing uncoordinated market expansion strategies, as well as from the strategic intent of firms seeking mutual forbearance with their rivals. Are the performance effects of unintended multimarket contacts different from those of purposeful contacts? Results in the US airline industry indicate that they are not. Multimarket contacts have a constant marginal effect on margins regardless of whether they occur at a level below or above the level that would be expected just by chance. In this case, the performance effect of multimarket contact is determined by the realized strategy, regardless of whether it was deliberate or emergent. Implications for other areas of strategy research are discussed. Copyright © 2002 John Wiley & Sons, Ltd.
Turnarounds
Authors: Furman Jeffrey L. , McGahan Anita M.
Published: October 2002

For many years, business turnarounds have captured the attention of scholars and fascinated executives. Yet despite their centrality as a business phenomenon, little is known about the prevalence or trajectory of turnarounds. This paper provides evidence on a broad cross‐section of publicly traded companies to fill the gap. The results indicate that since 1987 the financial‐market premium on businesses with very low performance has been higher than the premium on companies with moderately low performance. Since 1993 the premium escalated dramatically, consistent with the idea that investors became increasingly enthusiastic about the prospect of turnarounds. The evidence suggests that this enthusiasm may be unfounded: During the 1980s and 1990s, businesses that experienced an episode of profitability in the lowest quintile of the economy rarely both retained their organizational stability and rebounded to achieve performance in the top quintile. In particular, very low performers that reported financial results as stable entities for 5 years were 3.4 times as likely to sustain their very low performance as to become very high performers. Similarly, only 3% of businesses that posted very high performance after having survived a 5‐year period had been very low performers at the beginning of the period. The paper also identifies several of the exceptional businesses that remained independent, survived, and accomplished turnarounds during the 1980s and 1990s, and shows that the financial markets were not effective at identifying their impending turnarounds ex ante. Copyright © 2002 John Wiley & Sons, Ltd.
Dopamine transporter density is decreased in parkinsonian patients with a history of manganese exposure: What does it mean?
Authors: Kim Y. , Kim J.‐M. , Kim J.‐W. , Yoo C.‐I. , Lee C.R. , Lee J.H. , Kim H.K. , Yang S.O. , Chung H.K. , Lee D.S. , Jeon B.
Published: October 2002

Manganese (Mn) exposure can cause parkinsonism. Pathological changes occur mostly in the pallidum and striatum. Two patients with a long history of occupational Mn exposure presented with Mn‐induced parkinsonism. In one patient, magnetic resonance imaging (MRI) showed findings consistent with Mn exposure, and Mn concentration was increased in the blood and urine. However, this patient's clinical features were typical of idiopathic Parkinson disease (PD). Previous pathological and positron emission tomography studies indicate that striatal dopamine transporter density is normal in Mn‐induced parkinsonism, whereas it is decreased in PD. Therefore, we performed [123I]‐(1r)‐2β‐carboxymethoxy‐3β‐(4‐iodophenyl)tropane ([123I]‐β‐CIT) single‐photon emission computed tomography. Severe reduction of striatal β‐CIT binding was indicated, which is consistent with PD. We propose three interpretations: (1) the patients have PD, and Mn exposure is incidental; (2) Mn induces selective degeneration of presynaptic dopaminergic nerve terminals, thereby causing parkinsonism; or (3) Mn exposure acts as a risk of PD in these patients. Our results and careful review of previous studies indicate that the axiom that Mn causes parkinsonism by pallidal lesion may be over‐simplified; Mn exposure and parkinsonism may be more complex than previously thought. Further studies are required to elucidate the relationship between Mn and various forms of parkinsonism. © 2002 Movement Disorder Society
Bilateral pallidotomy in Parkinson's disease: A retrospective study
Authors: De Bie Rob M.A. , Schuurman P. Richard , Esselink Rianne A.J. , Bosch D.Andries , Speelman Johannes D.
Published: October 2002

We evaluated the effects of bilateral pallidotomy in patients with advanced Parkinson's disease. Thirteen patients with Parkinson's disease had a staged bilateral pallidotomy if they had severe response fluctuations, dyskinesias, painful dystonia, or bradykinesia despite optimum pharmacological treatment. Assessment scales were the Unified Parkinson's Disease Rating scale (UPDRS), the Schwab and England scale, and a questionnaire on the effects of disability in activities of daily living and adverse effects. Postoperative magnetic resonance imaging was evaluated for lesion location and extension. The median off‐phase UPDRS motor score was reduced from 43.5 to 29 after the first pallidotomy, and it was further reduced to 23.5 after the second pallidotomy (n = 8). The UPDRS activities of daily living off‐phase score improved from 28.5 to 20.5 after the first pallidotomy and to 19 after the second pallidotomy (n = 6). The Schwab and England scale off‐phase score showed an improvement after both procedures, first from 40 to 60, and thereafter to 90 (n = 8). On‐phase dyskinesias were reduced substantially. Eight patients had adverse effects, of whom five had problems with speech. One patient became hemiplegic due to a delayed infarction. Ten patients experienced further benefit from the second procedure. Bilateral pallidotomy reduces dyskinesias. A second contralateral pallidotomy may reduce parkinsonism, although to a lesser degree compared with the first pallidotomy and with an increased risk for adverse effects. © 2002 Movement Disorder Society
Therapeutic efficacy of bilateral prefrontal slow repetitive transcranial magnetic stimulation in depressed patients with Parkinson's disease: An open study
Authors: Dragaševic Nataša , Potrebić Aleksandra , Damjanović Aleksandar , Stefanova Elka , Kostić Vladimir S.
Published: October 2002

Recent studies have suggested that both high‐ and low‐frequency repetitive transcranial magnetic stimulation (rTMS) have antidepressant effects in patients with major depression. We conducted an open study to assess the effects of slow rTMS on mood changes in patients with depression associated with Parkinson's disease (PD). Ten depressed patients with PD (four with major depression and six with dysthymia) received daily sessions of rTMS (frequency, 0.5 Hz; pulse duration, 0.1 msec; field intensity, 10% above the motor threshold) over both prefrontal regions (a total of 100 stimuli per prefrontal region daily) over 10 consecutive days. This treatment resulted in a moderate but significant decrease in scores of the Hamilton Depression Rating Scale (33–37%) and the Beck Depression Inventory (24–34%), which persisted 20 days after finishing the stimulation. In parallel, we observed mild improvement (18–20%) of motor symptoms. No significant adverse effects were reported. These preliminary results suggest the therapeutic potential of daily prefrontal low‐frequency rTMS (0.5 Hz) in depression associated with PD. © 2002 Movement Disorder Society
Camptocormia in Parkinson's disease mimicked by focal myositis of the paraspinal muscles
Authors: Wunderlich Silke , Csoti Ilona , Reiners Karlheinz , Günthner‐Lengsfeld Thomas , Schneider Christiane , Becker Georg , Naumann Markus
Published: October 2002

We report on a 63‐year‐old man with idiopathic Parkinson's disease who developed kyphosis and a severe forward flexion of the thoracolumbar spine. A typical feature was an increase during walking or standing and it completely disappeared in the supine position, mimicking the clinical phenomenon of camptocormia (bent spine). In addition to the abnormal posture, a weakness of the erector spinal muscles, local pain, reddening, and elevated temperature of the paraspinal muscles were evident. Creatine kinase was initially elevated, electromyography showed spontaneous activity and a myopathic pattern. Magnetic resonance imaging and bioptic examinations revealed a focal myositis of the paraspinal muscles. This case indicates that camptocormia can be mimicked by focal myositis of paraspinal muscles and must be included in the differential diagnosis, especially when additional symptoms as inflammatory signs or weakness are present. © 2002 Movement Disorder Society.
Descending control of muscles in patients with cervical dystonia
Authors: Tijssen Marina A.J. , Münchau Alex , Marsden John F. , Lees Andrew , Bhatia Kailash P. , Brown Peter
Published: October 2002

It was reported recently that specific features in the frequency analysis of electromyographic (EMG) activity in the sternocleidomastoid (SCM) and splenius (SPL) muscles were able to distinguish between rotational idiopathic cervical dystonia (CD) and voluntary torticollis in individual subjects. Those with CD showed an abnormal drive to muscles at 5 to 7 Hz and an absence of the normal 10 to 12 Hz peak in the autospectrum of SPL. We sought to determine whether the same abnormalities in the frequency domain are found in complex CD, in which the head is displaced in more than two planes. EMG activity was recorded in the SCM, SPL, trapezius, and levator scapulae muscles bilaterally in 10 patients with complex CD. Frequency analysis of EMG was compared with conventional clinical and polymyographic assessment. The autospectrum of SPL during free dystonic contraction showed an absence of a significant peak at 10 to12 Hz in 8 of the 10 patients. The presence of a 5 to 7 Hz frequency drive showed a significant association with muscle pairs determined as dystonic by means of polymyography (P < 0.005). The neck posture predicted blindly, based on the low‐frequency drive, correlated significantly with the clinical assessment of posture (P < 0.01). Conventional assessment and the results of frequency analysis correlated, suggesting that a low‐frequency drive to neck muscle may be a general feature of simple rotational and more complex cervical dystonia. The pattern of coherence between the EMG in different neck muscles may provide a means of identifying leading dystonic muscles, especially in patients with complex cervical dystonia. © 2002 Movement Disorder Society
Diet and arterial hypertension: Is the sodium ion alone important?
Authors: Buemi Michele , Senatore Massimino , Corica Francesco , Aloisi Carmela , Romeo Adolfo , Tramontana Domenico , Frisina Nicola
Published: October 2002

Hypertension is a widespread phenomenon whose ultimate cause is still unknown. Many factors contribute to this disease, and partially for this reason, hypertension responds to different treatments in different individuals. It is difficult to generalize about therapies for general populations. In particular, the role of electrolytes in hypertension varies widely across individuals. This review focuses its attention on sodium, potassium, calcium, and magnesium ions in order to investigate whether these electrolytes play a role in the pathogenesis of arterial hypertension and its treatment. Some individuals are especially sensitive to sodium, and changing their intake of dietary sodium may lead to variations in the levels of the other electrolytes. These changes in electrolyte levels can complicate treatments for arterial hypertension in some patients. © 2002 Wiley Periodicals, Inc. Med Res Rev, 22, No. 4, 419–428, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/med.10013
A model of a general elastic curved rod
Authors: Ignat Anca , Sprekels Jürgen , Tiba Dan
Published: October 2002

We indicate a new approach to the deformation of three‐dimensional curved rods with variable cross‐section. The model consists of a system of nine ordinary differential equations for which we prove existence and uniqueness via the coercivity of the association bilinear form. From the geometrical point of view, we are using the Darboux frame or a new local frame requiring just a C1‐parameterization of the curve. Our model also describes the deformation occurring in the cross‐sections of the rod. Copyright © 2002 John Wiley & Sons, Ltd.
A slow‐wave structure with Koch fractal slot loops
Authors: Kim Jung‐Hyo , Kim Il‐Kwon , Yook Jong‐Gwan , Park Han‐Kyu
Published: October 2002

In this Letter, a Koch slot loop in the ground plane has been utilized to obtain slow‐wave characteristics, and its electrical performances are analyzed with the use of the ABCD matrix approach. The validity of this approach has been verified through experimental results, and this technique was then applied to microstrip patch antennas in order to obtain a small antenna size. The cross‐sectional areas of this type of antenna are 47% to 65% smaller than those of conventional square patches. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 87–88, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10381
Simple CAD formula for inductance calculation of square spiral inductors with grounded substrate by duality and synthetic asymptote
Authors: Tang Wan C. , Chow Y. Leonard
Published: October 2002

This Letter gives simple CAD formulas for the inductance calculation of a square spiral inductor on a grounded substrate, by duality and synthetic asymptote at low frequency. The average errors of the formulas are less than 2%. The formulas also give good physical insights to the layout of the spiral inductor. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 93–96, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10383
Two novel methods for analyzing multipath interference in distributed fiber Raman amplifiers
Authors: Mei Jin‐Jie , Liu De‐Ming , Huang De‐Xiu
Published: October 2002

Based on comparing the analyzing methods in existence for multipath interference (MPI) resulted from Rayleigh backscattering in distributed fiber Raman amplifiers (DFRA), two novel methods are presented. A simple analytical expression is developed in the first method. The evolution of optical powers within each step is calculated by a semianalytical method in the second so that the MPI calculating time can be saved and the precision can be improved. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 109–112, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10388
Optical WDM rings using a smart wavelength routing assignment
Authors: Podcameni Abelardo , Mosso Marbey
Published: October 2002

Functionality is inserted into the physical layer of WDM optical networks in order to provide for an efficient carrier routing and packet‐addressing scheme. No optoelectronic conversions are needed along the network nodes, except at the source and destination nodes. Tuned transmitters or receivers are not used. The ancillary network routing management structure is dramatically reduced, together with the total network cost. Simple and efficient mechanisms to avoid optical carrier modulation inefficiency and data collision are introduced. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 121–125, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10392
An equivalent waveguide approach to designing of reflect arrays with the use of variable‐size microstrip patches
Authors: Tsai Feng‐Chi E. , Bialkowski Marek E.
Published: October 2002

An equivalent unit cell waveguide approach (WGA) is described to study the behavior of a multilayer reflect array of variable‐size patches/dipoles. The approach considers normal incidence of a plane wave on an infinite periodic array of identical radiating elements and introduces an equivalent unit cell waveguide to obtain the reflection coefficient. A field matching technique and method of moments (MoM) is used to determine fields in different layers of the equivalent waveguide. Good agreements for the phase of the reflection coefficient between the proposed model and those published in selected literatures are obtained. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 172–175, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10407
A coaxial probe feed model for FDTD
Authors: Mäkinen Riku , Kangas Ville , Lahtinen Janne , Kivikoski Markku
Published: October 2002

A new FDTD model for a coaxial probe feed based on transmission lines is proposed. Both the metal probe and a material boundary at the transmission line to FDTD interface are accurately modeled. Comparisons with experimental data indicate a significant improvement compared with a previously published transmission‐line feed model. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 193–198, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10415
Application of the preconditioned conjugate‐gradient algorithm to the integral equations for microwave circuits
Authors: Tsang K. F. , Chen R. S. , Lei Mo , Yung Edward K. N.
Published: October 2002

In this Letter, both the banded diagonal matrix and the symmetric successive overrelaxation (SSOR) precondition CG techniques are applied to dense matrix equations from the mixed potential integral equation (MPIE) to enhance computational efficiency. Numerical calculations show that the banded diagonal matrix preconditioned conjugate‐gradient (CG) technique is efficient only for the discretization along one dimension, whereas the SSOR scheme is efficient for the discretization in two dimensions. Some typical microstrip discontinuities are analyzed and good results demonstrate the validity of the proposed algorithms. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 34: 266–270, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10434