bluuebunny/crossref_metadata_2025_split huggingface dataset:
Browning in processed yams: peroxidase or polyphenol oxidase?
Authors: Chilaka Ferdinand C , Eze Sabinus , Anyadiegwu Clement , Uvere Peter O 
Published: October 2002

AbstractPolyphenol 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

AbstractIntake 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

AbstractA 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

AbstractThe 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

AbstractDietary 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

AbstractThe 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

AbstractObjectivesThis study was conducted to determine clinical and histologic factors that would predict nodal metastasis in patients with major salivary gland cancer.MethodsA 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.ResultsNeck 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).ConclusionsOur 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

AbstractThe 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

AbstractGay 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

AbstractWe 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

AbstractBackground and ObjectivesSapphire 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 MethodsThree 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.ResultsIn 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.ConclusionsThe 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

AbstractBoth 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

AbstractWe 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

AbstractManagerial 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

AbstractStrategic 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

AbstractMultimarket 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.