bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacterial diversity promotes community stability and functional resilience after perturbation
Authors: Girvan M. S. , Campbell C. D. , Killham K. , Prosser J. I. , Glover L. A. 
Published: January 2005

SummaryThe relationships between bacterial community diversity and stability were investigated by perturbing soils, with naturally differing levels of diversity, to equivalent toxicity using copper sulfate and benzene. Benzene amendment led to large decreases in total bacterial numbers and biomass in both soils. Benzene amendment of an organo‐mineral/improved pasture soil altered total soil bacterial community structure but, unlike amendment of the mineral/arable soil, maintained genetic diversity, based on polymerase chain reaction‐denaturing gradient gel electrophoresis (PCR‐DGGE ) analysis targeting DNA and RNA, until week 9 of the perturbation experiment. Assuming equivalent toxicity, the genetic diversity of the naturally more diverse soil was more resistant to benzene perturbation than the less diverse soil. The broad scale function (mineralization of 14C‐labelled wheat shoot) of both benzene‐ and copper‐treated soil communities was unaffected. However, narrow niche function (mineralization of 14C‐labelled 2,4‐dichlorophenol) was impaired for both benzene‐polluted soils. The organo‐mineral soil recovered this function by the end of the experiment but the mineral soil did not, suggesting greater resilience in the more diverse soil. Despite a large reduction in bacterial numbers and biomass in the copper‐treated soils, only small differences in bacterial community diversity were observed by week 9 in the copper‐polluted soils. The overall community structure was little altered and functionality, measured by mineralization rates, remained unchanged. This suggested a non‐selective pressure and a degree of genetic and functional resistance to copper perturbation, despite a significant reduction in bacterial numbers and biomass. However, initial shifts in physiological profiles of both copper‐polluted soils were observed but rapidly returned to those of the controls. This apparent functional recovery, accompanied by an increase in culturability, possibly reflects adaptation by the surviving communities to perturbation. The findings indicate that, although soil communities may be robust, relationships between diversity and stability need to be considered in developing a predictive understanding of response to environmental perturbations.
Sensitive skin: mechanisms and diagnosis
Authors: Primavera G. , Berardesca E. 
Published: February 2005

SynopsisSensitive skin is a condition of subjective cutaneous hyperreactivity to environmental factors. Subjects experiencing this condition report exaggerated reactions when their skin is in contact with cosmetics, soaps and sunscreens, and they often report worsening after exposure to dry and cold climate. Although no sign of irritation is commonly detected, itching, burning, stinging and a tight sensation are constantly present. Generally substances that are not commonly considered irritants are involved in this abnormal response. They include many ingredients of cosmetics such as: dimethyl sulfoxide, benzoyl peroxide preparations, salicylic acid, propylene glycol, amyldimethylaminobenzoic acid and 2‐ethoxyethyl methoxycinnamate. Sensitive skin and subjective irritation are widespread but still far from being completely defined and understood. The aim of this paper is to summarize the relevant literature in order to elucidate the underlying mechanisms of sensitive skin and the best testing methodologies for investigation of sensitive skin.
NATIONAL IDENTITY IN NIAGARA FALLS, CANADA AND THE UNITED STATES
Authors: STIEVE THOMAS 
Published: January 2005

ABSTRACTSome theories contend that national identity is dependent and contingent on having others. However, other theories suggest that national identity is based on traits that all members of the group share. These two competing ideas, called relational and unifying characters respectively, are explored using the two border cites of Niagara Falls, Canada and Niagara Falls, the United States. I argue that each national identity present, the Canadian and American, represent the two characters and that national identity can be viewed as a spectrum. Using content analysis, each city's newspaper is studied for its expression of both characters.
GLOBALISATION AND RESTRUCTURING IN RURAL MEXICO: THE CASE OF FRUIT GROWERS
Authors: ECHÁNOVE FLAVIA 
Published: January 2005

ABSTRACTMexico is the leading mango‐exporting country in the world. In this global commodity chain there is an important participation by small‐scale farmers whose products end up in US supermarkets. This paper analyses the linkages between the agriculture sector in a developing country and the global agro‐food system. Drawing on the development geography approach and the global commodity‐chain perspective, the effects and responses of global processes on local development are analysed by examining the relations between fruit export companies, local growers and consumer markets. Our case study is of small farmers (ejidatarios) who grow mangos in one of Mexico's main export‐oriented agricultural areas, the Bahía de Banderas Valley, and whose situation is similar to other small‐scale producers of non‐traditional products. The study examines the impact on the farmers of structural adjustment policies that have been implemented in Mexico since the mid‐1980s. It also examines the main livelihood strategies that ejidatarios and their households have been adopting during the same period.
Reflectivity in supervised practice: conventional and transformative approaches to physiotherapy
Authors: Lähteenmäki Marja‐Leena 
Published: January 2005

AbstractThis article sets out to discover how learning could be enhanced in the physiotherapy training given on placements. The study describes the experiences of 32 physiotherapy students during their trainee periods and focuses on their views of the supervision provided and of its effects on their performance. The research data were collected from discussions conducted in six small groups over a period of 2.5 years. In order to refresh the participants’ memory, videotaped extracts from their training sessions were shown during the discussions. An ethnomethodological method was applied in both collecting and analysing the data. The results show that conventional instruction led to continued adherence to the model given. The transformative approach, in contrast, encouraged the students to learn through reflection as they observed and analysed physiotherapy sessions, discussed with their supervisor and worked on their written assignments. Moreover, reflective learning helped the students as they were given more responsibility for their own actions. When supervisors asked the students questions or did not immediately provide direct answers, students learned to analyse situations themselves as well as to look for information and to find solutions. These methods appear to be the ‘keys’ in transformative physiotherapy training in which four phases are cyclically repeated: the experience gained from therapy sessions; the reflection prompted by supervisor–student discussions; the planning which incorporates clinical reasoning; and the actual therapy sessions together with guidance. Based on these findings and on the empirical evidence, a model of supervision, which encourages reflective learning and transformative physiotherapy, has been outlined.
INTERSTATE BANKING DEREGULATION AND THE CHANGING NATURE OF BANK MERGERS
Authors: Becher David A. , Campbell Terry L. 
Published: February 2005

AbstractWe examine a sample of 443 bank mergers between publicly traded banks announced during the 1990s to investigate empirically the role of full interstate banking deregulation. The pre‐deregulation 1990s are characterized by value creation, with mergers involving a high degree of branch overlap experiencing significant announcement gains. Bank mergers in the post‐deregulation 1990s, however, fail to create value, and mergers with a high degree of branch overlap actually experience significant losses. Consistent with prior research, these valuation consequences are magnified for large bank mergers in the 1990s. Overall, our results are consistent with the broader literature on corporate control, suggesting that an economic shock can materially alter industry structure and the economic rationale for the efficient reallocation of assets through merger activity.
THE MEAN‐GINI EFFICIENT PORTFOLIO FRONTIER
Authors: Shalit Haim , Yitzhaki Shlomo 
Published: February 2005

AbstractA main advantage of the mean‐variance (MV) portfolio frontier is its simplicity and ease of derivation. A major shortcoming, however, lies in its familiar restrictions, such as the quadraticity of preferences or the normality of distributions. As a workable alternative to MV, we present the mean‐Gini (MG) efficient portfolio frontier. Using an optimization algorithm, we compute MG and mean‐extended Gini (MEG) efficient frontiers and compare the results with the MV frontier. MEG allows for the explicit introduction of risk aversion in building the efficient frontier. For U.S. classes of assets, MG and MEG efficient portfolios constructed using Ibbotson (2000) monthly returns appear to be more diversified than MV portfolios. When short sales are allowed, distinct investor risk aversions lead to different patterns of portfolio diversification, a result that is less obvious when short sales are foreclosed. Furthermore, we derive analytically the MG efficient portfolio frontier by restricting asset distributions. The MG frontier derivation is identical in structure to that of the MV efficient frontier derivation. The penalty paid for simplifying the search for the MG efficient frontier is the loss of some information about the distribution of assets.
TRADE SIZE AND INFORMED TRADING: WHICH TRADES ARE “BIG”?
Authors: Heflin Frank , Shaw Kenneth W. 
Published: February 2005

AbstractWe find adverse‐selection spread components increase sharply in the ratio of trade size to quoted depth, and spike when trade size equals quoted depth. We find that two previously documented and prominent indicators of informed trading, raw trade size and high‐trading volume half‐hours, offer almost no explanatory power for informed trading measures beyond trade size to quoted depth, and a third indicator, time of day, offers no explanatory power among trades with high trade size to quoted depth. Our results suggest trade size to quoted depth is perhaps the single most important indicator that a trade is informed.
Frequent promoter hypermethylation of RASSF1A and p16INK4a and infrequent allelic loss other than 9p21 in betel‐associated oral carcinoma in a Vietnamese non‐smoking/non‐drinking female population
Authors: Tran Tu Ngoc , Liu Yenchun , Takagi Minoru , Yamaguchi Akira , Fujii Hiroaki 
Published: February 2005

Background:  Betel‐chewing, a risk factor for oral carcinoma, is a common habit of elderly Vietnamese females, but concomitant habits of tobacco and alcohol are uncommon.Methods:  In the present study, 36 paraffin‐embedded betel‐associated oral carcinoma samples including 27 squamous cell carcinoma (SCC) and nine verrucous carcinomas (VC) were analyzed for the hypermethylation of tumor suppressor genes (TSGs) and loss of heterozygosity (LOH) of important TSG loci. Methylation‐specific polymerase chain reaction (MSP) was used to identify promoter hypermethylation of p16INK4a and RASSF1A. For LOH analysis, 39 microsatellite markers at 12 chromosomal arms were examined by p olymerase chain reaction (PCR)‐based microsatellite assay.Results:  Hypermethylation of p16IKN4a was detected in 63% of SCC and 67% of VC. In addition, LOH at 9p21 (locus for p16INK4a) was 58% for SCC and 22% for VC, and hypermethylation of RASSF1A was 93% for SCC and 100% for VC. LOH at 3p21.3–3p22.1 (where RASSF1A is located) was detected in only 12% of SCC and 0% of VC. LOH of other chromosomal arms were infrequent.Conclusion:  As LOH for chromosomes other than 9p was uncommon, epigenetic silencing of RASSF1A and p16INK4a gene expression by promoter hypermethylation may play a critical role in betel‐associated oral carcinogenesis.
Functional assessment of a washing emulsion for sensitive skin: mild impairment of stratum corneum hydration, pH, barrier function, lipid content, integrity and cohesion in a controlled washing test
Authors: Bornkessel A. , Flach M. , Arens‐Corell M. , Elsner P. , Fluhr J. W. 
Published: February 2005

Background/purpose: Sensitive skin has been described as a skin type with higher reactivity than normal skin and exaggerated reactions to external irritants. Washing with soaps is harmful for barrier‐related parameters. Cutaneous irritation induced by cleansing products under exaggerated test conditions, e.g. patch testing, is not necessarily predictive of the irritation occurring under standardized daily use conditions. The purpose of the study was to assess the effect of an improved washing solution for sensitive skin in a half‐site comparison on barrier‐related parameters.Methods: Thirty healthy volunteers with self‐reported sensitive and so‐called problematic skin performed standardized washings with a soap‐free washing emulsion with mild acidity (pH 5.5) for 3 weeks. Test areas were both forearms and the cheek. Non‐invasive biophysical measurements of the following skin parameters, epidermal permeability barrier function measured as transepidermal water loss (TEWL), stratum corneum (SC) hydration, pH value, skin surface lipids, skin temperature and SC integrity/cohesion, were assessed prior to the first washing, on days 7, 14 and 21 after beginning the washing procedure. SC cohesion was quantified using two independent methods on D‐Squame tapes: optical spectroscopy measuring the absorbance and a protein assay assessing the total protein (Bradford). Both methods showed a good correlation. SC integrity was quantified by measuring TEWL after sequential stripping with D‐Squame tapes.Results: The use of the washing emulsion led to a mild damage of the epidermal permeability barrier function with no marked difference to water application. Furthermore, a mild but significant dehydration was assessed after 21 days vs. baseline without any differences between the water‐treated and the washing emulsion‐treated forearm. On the cheek no dehydration was detectable but the lipid content was reduced under the washing emulsion. The pH value increased in all three test areas after 21 days, again without significant differences between water and the washing solution. SC cohesion was quantified using two independent methods on D‐Squame tapes: optical spectroscopy measuring the absorbance and a protein assay assessing the total protein (Bradford). Both methods showed a good correlation. The SC cohesion decreased after 21 days on the water‐treated as well as on the washing emulsion‐treated arm. The decrease over time was significant when used the optical spectroscopy measuring. A standardized questionnaire revealed positive characteristics of the washing emulsion and good acceptance.Conclusion: The investigated standardized washing model with the endpoints epidermal barrier function, SC hydration, surface pH, skin surface lipids, skin temperature and SC integrity/cohesion showed only mild damage comparable to washing with water.
Colors in atypical nevi: a computer description reproducing clinical assessment
Authors: Seidenari Stefania , Pellacani Giovanni , Grana Costantino 
Published: February 2005

Background/purpose: Atypical nevi (AN) share some dermoscopic features with early melanoma (MM), and computer elaboration of digital images could represent a useful support to diagnosis to assess automatically colors in AN, and to compare the data with those referring to clearly benign nevi (BN) and MMs.Methods: An image analysis program enabling the numerical description of color areas in melanocytic lesions was used on 459 videomicroscopic images, referring to 76 AN, 288 clearly BN and 95 MMs.Results: Black, white and blue‐gray were more frequently found in AN than in clearly BN, but less frequently than in MMs. Color area values significantly differed between the three groups.Conclusion: The clinical–morphological interpretation of the numerical data, based on the mathematical description of the aspect and distribution of different color areas in different lesion types may contribute to the characterization of AN and their distinction from MMs.
Effect of a preparation containing a fucose‐rich polysaccharide on periorbital wrinkles of human voluntaries
Authors: Robert C. , Robert A.M. , Robert L. 
Published: February 2005

Background: Skin aging is accompanied by wrinkle formation. At some sites, as the periorbital skin, this is a relatively early phenomenon, variable from one woman to the other and even between the right and left eye.Purpose: We tested the effect of a preparation with fucose‐rich oligo‐ and polysaccharide (FROP‐3) on periorbital wrinkles (crow's feet) on a team of voluntaries.Method: The efficiency of a preparation containing as active principle a fucose‐rich polysaccharide in a base‐cream for the treatment of temporal periorbital wrinkles on 20 voluntary women was tested as follows: the women applied the cream twice a day for 4 weeks. Negative replicas were taken on the periorbital skin before and after 4 weeks of application of the cream. The results were evaluated by semi‐automated morphometry on the plastic replicas and expressed as the ‘wrinkle‐factor’ obtained by multiplying total wrinkle length in millimeters by the average wrinkle width.Results: After 4 weeks of treatment, there was a significant improvement of the periorbital wrinkles for the majority of the voluntary team who tested the cream. On the 29 periocular wrinkles examined 65% showed an improvement at the end of the treatment. In two cases, the improvement was 100% on one eye (disappearance of the crow's feet) and of 75% and 79% on the other eye. On six eyes, there was no significant change after the end of the treatment, and on four eyes a worsening was observed. The age‐dependent modifications showed that improvement was independent of age and was the result of individual skin reactions to the cream. The occurrence and the severity of crow's feet is highly individual, and differs from one side of the face to the other for the same person. These strong individual variations explain the highly variable results, not only from one woman to the other but also comparing one side of the face to the other for the same person.Conclusion: Under the effect of 4 weeks of treatment with the FROP‐3‐containing cream, most of the voluntaries had their periorbital wrinkles attenuated and some women showed a total regression of crow's feet on one of their eyes.
Low-Valent Titanocene Products from Attempted Syntheses of Titanocene Bearing Dimethyl(3,3,3-trifluoropropyl)silyl Groups
Authors: Lukešová Lenka , Horáček Michal , Gyepes Róbert , Císařová Ivana , Štěpnička Petr , Kubišta Jiří , Mach Karel 
Published: February 2005

Reduction of silyl-substituted titanocene dichloride [TiCl2{η5-C5Me4(SiMe2CH2CH2CF3)}2] (1) with one molar equivalent of magnesium afforded a mixture of products, thus precluding the isolation of the possibly formed titanocene [Ti{(η5-C5Me4(SiMe2CH2CH2CF3)}2]. The presence of isolable monochloride [TiCl{η5-C5Me4(SiMe2CH2CH2CF3)}2] (2) in the mixture indicates that the mangnesium is consumed in concurrent reactions, that produce various titanocene compounds of which some were obtained by the reduction of 1 with excess magnesium. Those include the trinuclear TiIII-MgII-TiIII hydride-bridged complex [Ti{η5-C5Me4- (SiMe2CH2CH2CF3)}2(μ-H)2]2Mg (3) and a dimeric dinuclear Ti-Mg complex 4 containing the [TiIII(μ-H)2Mg(μ-X)]2 core where, however, the nature of the bridging moiety X remains unknown. The reduction of 1 with excess magnesium in the presence of bis(trimethylsilyl)ethyne afforded the product of C-H activation [Ti{η5-C5Me4(SiMe2CH2CH2CF3)}- {η5:η1-C5Me3(CH2)(SiMe2CH2CH2CF3)}] (5) in 47% yield. This compound reacted rapidly with tert-butylethyne to give the TiIII-acetylide complex [Ti(η1-C≡CCMe3){η5-C5Me4- (SiMe2CH2CH2CF3)}2] (6). All the reductions of 1 at molar ratios Mg:Ti ≥ 1 gave mixtures, where a good deal of the reduction products remained in the mother liquors unidentified. The structures of 1, 2, 3, 5, and 6 were determined by X-ray diffraction analysis and, for 2, 3, 4, 5, and 6, further corroborated by ESR spectra.
Transmembrane CEACAM1 affects integrin-dependent signaling and regulates extracellular matrix protein–specific morphology and migration of endothelial cells
Authors: Müller Mario M. , Singer Bernhard B. , Klaile Esther , Öbrink Björn , Lucka Lothar 
Published: February 2005

AbstractCarcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1/CD66a), expressed on leukocytes, epithelia, and endothelia mediates homophilic cell adhesion. It plays an important role in cell morphogenesis and, recently, soluble CEACAM1 isoforms have been implicated in angiogenesis. In the present study, we investigated the function of long transmembrane isoform of CEACAM1 (CEACAM1-L) in cultured rat brain endothelial cells. We observed that expression of CEACAM1-L promotes network formation on basement membrane Matrigel and increased cell motility after monolayer injury. During cell-matrix adhesion, CEACAM1-L translocated into the Triton X-100–insoluble cytoskeletal fraction and affected cell spreading and cell morphology on Matrigel and laminin-1 but not on fibronectin. On laminin-1, CEACAM1-L–expressing cells developed protrusions with lamellipodia, showed less stress fiber formation, reduced focal adhesion kinase (FAK) tyrosine phosphorylation, and decreased focal adhesion formation leading to high motility. CEACAM1-L–mediated morphologic alterations were sensitive to RhoA activation via lysophosphatidic acid (LPA) treatment and dependent on Rac1 activation. Furthermore, we demonstrate a matrix protein–dependent association of CEACAM1-L with talin, an important regulator of integrin function. Taken together, our results suggest that transmembrane CEACAM1-L expressed on endothelial cells is implicated in the activation phase of angiogenesis by affecting the cytoskeleton architecture and integrin-mediated signaling.
Deficiency in the p110α subunit of PI3K results in diminished Tie2 expression and Tie2-/-–like vascular defects in mice
Authors: Lelievre Etienne , Bourbon Pierre-Marie , Duan Li-Juan , Nussbaum Robert L. , Fong Guo-Hua 
Published: February 2005

AbstractPhosphoinositide 3-kinase (PI3K) is activated by transmembrane tyrosine kinases such as vascular endothelial growth factor (VEGF) receptors and Tie2 (tunica intima endothelial kinase 2), both of which are key regulators of vascular development. However, the in vivo role of PI3K during developmental vascularization remains to be defined. Here we demonstrate that mice deficient in the p110α catalytic subunit of PI3K display multiple vascular defects, including dilated vessels in the head, reduced branching morphogenesis in the endocardium, lack of hierarchical order of large and small branches in the yolk sac, and impaired development of anterior cardinal veins. These vascular defects are strikingly similar to those in mice defective in the Tie2 signaling pathway. Indeed, Tie2 protein levels were significantly lower in p110α-deficient mice. Furthermore, RNA interference of p110α in cultured endothelial cells significantly reduced Tie2 protein levels. These findings raise the possibility that PI3K may function as an upstream regulator of Tie2 expression during mouse development.