bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simultaneous constraining of model and data smoothness for regularization of geophysical inverse problems
Authors: Gholami A. , Siahkoohi H. R. 
Published: November 2008

Summary
In this paper, a new approach is introduced to solve ill-posed linear inverse problems in geophysics. Our method combines classical quadratic regularization and data smoothing by imposing constraints on model and data smoothness simultaneously. When imposing a quadratic penalty term in the data space to control smoothness of the data predicted by classical zero-order regularization, the method leads to a direct regularization in standard form, which is simple to be implemented and ensures that the estimated model is smooth. In addition, by enforcing Tikhonov's predicted data to be sparse in a wavelet domain, the idea leads to an efficient regularization algorithm with two superior properties. First, the algorithm ensures the smoothness of the estimated model while substantially preserving the edges of it, so, it is well suited for recovering piecewise smooth/constant models. Second, parsimony of wavelets on the columns of the forward operator and existence of a fast wavelet transform algorithm provide an efficient sparse representation of the forward operator matrix. The reduced size of the forward operator makes the solution of large-scale problems straightforward, because during the inversion process, only sparse matrices need to be stored, which reduces the memory required. Additionally, all matrix–vector multiplications are carried out in sparse form, reducing CPU time.
Applications on both synthetic and real 1-D seismic-velocity estimation experiments illustrate the idea. The performance of the method is compared with that of classical quadratic regularization, total-variation regularization and a two-step, wavelet-based, inversion method.
EGFR, HER‐2 and COX‐2 levels in colorectal cancer
Authors: Antonacopoulou A G , Tsamandas A C , Petsas T , Liava A , Scopa C D , Papavassiliou A G , Kalofonos H P 
Published: November 2008

Aims:  Receptor tyrosine kinases epidermal growth factor receptor (EGFR) and HER‐2 and cyclooxygenase‐2 (COX‐2) are promising molecular targets for cancer therapy and/or prevention. The aim was to evaluate EGFR, HER‐2 and COX‐2 mRNA and protein expression in colorectal cancer patients.Methods and results:  EGFR, HER‐2 and COX‐2 protein levels were evaluated by immunohistochemistry in malignant tissue, dysplastic tissue and normal mucosa samples from 124 cases with primary colorectal carcinoma. Moreover, the corresponding mRNA levels were assessed by quantitative reverse transcriptase‐polymerase chain reaction in 46 colorectal carcinomas. There was strong correlation between mRNA and protein expression for EGFR (P < 0.001), HER‐2 (P < 0.004) and COX‐2 (P < 0.007). EGFR levels did not correlate with stage of the disease or tumour differentiation. HER‐2 and COX‐2 levels increased in advanced stages and in differentiated carcinomas. Furthermore, a correlation between HER‐2 and COX‐2 expression was revealed in neoplastic tissue.Conclusions:  EGFR as well as HER‐2 and COX‐2 overexpression represent important alterations that are related to the molecular pathways underpinning colorectal carcinogenesis. Further investigation is required to evaluate the impact of these markers on the management of patients with colorectal cancer.
Deregulated expression of p16INK4a and p53 pathway members in benign and malignant myoepithelial tumours of the salivary glands
Authors: Vékony H , Röser K , Löning T , Raaphorst F M , Leemans C R , Van der Waal I , Bloemena E 
Published: November 2008

Aims:  Myoepithelial salivary gland tumours are uncommon and follow an unpredictable biological course. The aim was to examine their molecular background to acquire a better understanding of their clinical behaviour.Methods and results:  Expression of protein (E2F1, p16INK4a, p53, cyclin D1, Ki67 and Polycomb group proteins BMI‐1, MEL‐18 and EZH2) was investigated in 49 benign and 30 primary malignant myoepithelial tumours and five histologically benign recurrences by immunohistochemistry and the findings correlated with histopathological characteristics. Benign tumours showed a higher percentage of cells with expression of p16INK4a pathway members [p16INK4a and E2F1 (both P < 0.001), and cyclin D1, P = 0.002] compared with normal salivary gland. Furthermore, malignant tumours expressed p53 (P = 0.003) and EZH2 (P = 0.09) in a higher percentage. Recurrences displayed more p53 + tumour cells (P = 0.02) than benign primaries. Amongst the benign tumours, the clear cell type had the highest proliferation fraction (P = 0.05) and a higher percentage of EZH2 was detected in the plasmacytoid cell type (P = 0.002).Conclusions:  This study is the first to demonstrate that deregulation of the p16INK4a senescence pathway is involved in the development of myoepithelial tumours. We propose that additional inactivation of p53 in malignant primaries and benign recurrences contributes to myoepithelial neoplastic transformation and aggressive tumour growth.
Alternative fish species for cold‐smoking process
Authors: Gómez‐Guillén Ma Carmen , Gómez‐Estaca Joaquín , Giménez Begońa , Montero Pilan 
Published: November 2008

SummarySuitability of sardine (lean and fatty), dolphinfish and blue whiting for cold‐smoking was evaluated. Stable water‐holding capacity was observed in dolphinfish and blue whiting, but this tended to decrease in sardine throughout the storage. The 2‐thiobarbituric acid index was not suitable for lipid oxidation measure in these smoked fishes and rancid flavours were only detected in sardine at the end of storage period. Total volatile basic nitrogen tended to increase in all three species. Lactic acid bacteria became the dominant microflora and Enterobacteriaceae did not show any growth. A bacteriostatic effect of at least 21 days was observable in all the smoked species. Sensory shelf life was 11 weeks for both types of sardine and 9 weeks for dolphinfish and blue whiting. Softening of muscle tissue and the development of bitter and off flavours were the main causes of rejection. Smoking as a processing technology can be used to add value to excess sardine and dolphinfish catches, due to sensory acceptability ratings. In contrast, the blue whiting was not suitable for smoking due to unacceptable soft texture, a characteristic of this species.
Effects of high‐pressure treatment on the extraction yield, phenolic content and antioxidant activity of litchi (Litchi chinensis Sonn.) fruit pericarp
Authors: Prasad Nagendra K. , Yang Bao , Zhao Mouming , Wang Biao S. , Chen Feng , Jiang Yueming 
Published: November 2008

SummaryAs a promising technique, high‐pressure extraction (HPE) method was used to extract bioactive compounds from litchi fruit pricarp. The study involved in different experimental factors such as solvent, ethanol concentration (35‐95, v/v), material to solvent ratio (1:25‐1:100, w/v), acidic medium, extraction pressure (200‐500 MPa), time (2.5‐30 min) and temperature (30‐90 °C). The extraction yield, total phenolic contents, 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging activity and superoxide anion scavenging capability of the HPE sample were examined and then compared with those of ultrasonic extraction and conventional extraction samples. The application of HPE obtained higher extraction yield compared to other extraction methods. However, there were no significant differences (P > 0.05) in the total phenolic content and the antioxidant activities among these various extractions. Compared with some conventional extraction method, the HPE exhibited higher extraction efficiency in terms of higher extraction yield and extraction time.
Nonstationary spatio‐temporal small rodent dynamics: evidence from long‐term Norwegian fox bounty data
Authors: Henden John‐André , Ims Rolf A. , Yoccoz Nigel G. 
Published: November 2008

Summary

The geographical pattern in Fennoscandian small rodent population dynamics with a southern noncyclic and a northern cyclic region, and with latitudinal gradients in density‐dependent structure, cycle period length and spatial synchrony within the northern cyclic region, has been widely publicized and interpreted in the ecological literature. However, the time‐series data on which these inferences have been established are relatively short and originate from a specific time period (mostly around 1970–90). Hence, it can be questioned whether the geographical population dynamics patterns are consistent over time (i.e. whether they are stationary).
Here we analyse an almost century long (1880–1976) panel of fox bounty time series including 18 counties of Norway, thus spanning the whole range of latitudes of Fennoscandia (i.e. 15 latitudinal degrees). These fox time series mirror the dynamics of their dominant small rodent prey, in particular, with respect to cycle period length and spatial synchrony.
While we found some evidence consistent with previous analyses showing a clearly patterned dynamics according to latitude, such patterns were not stationary on a longer time‐scale. In particular, we observed a shift from an extensively synchronous (i.e. regionalized) 4‐year cycle north of 60°N just after the ‘Little Ice Age’ (1880–1910) to a diversification of cycle period length (3–5 years) and eventually, partial loss of cyclicity and synchronicity in later periods. Incidents of loss of cyclicity appeared to be preceded by changes in cycle period (i.e. period lengthening and shortening).
These results show that the dynamics of Fennoscandian small rodents, and their associated guild of predators, are more prone to change than previously acknowledged.
Regression of language and non‐language skills in pervasive developmental disorders
Authors: Meilleur A.‐A. S. , Fombonne E. 
Published: November 2008

AbstractBackground  As part of the pervasive developmental disorders (PDD), there is a subgroup of individuals reported to have a different onset of symptom appearance consisting of an apparently normal early development, followed by a loss of verbal and/or non‐verbal skills prior to 2 years of age. This study aims at comparing the symptomatology of children who displayed a regression and often an associated intellectual disability through investigation of two types of loss, namely language and other skill regression.Methods  This study examined the occurrence of regression in 135 children with PDD, mean age 6.3 years. The sample was composed of 80 (59.4%) children diagnosed with autism, 44 (32.6%) with pervasive developmental disorder‐not otherwise specified (PDD‐NOS) and 11 (8%) with Asperger syndrome. The Autism Diagnostic Interview Revised (ADI‐R) was used to evaluate the type of loss and to characterise associated factors including birth rank, gender and thimerosal exposure through vaccination.Results  A total of 30 (22%) subjects regressed: nine (30%) underwent language regression alone, 17 (57%) lost a skill other than language and four (13%) lost both language and another skill. Significantly higher levels of regression were found in autism (30%) compared with PDD‐NOS (14%) and Asperger syndrome (0%). Children who regressed in language skills spoke at a significantly earlier age ( = 12 months) than those who did not regress in this domain ( = 26 months). Parents and interviewers consistently reported developmental abnormalities prior to the loss. ADI‐R domain mean scores indicated a more severe autistic symptomatology profile in children who regressed compared with those who did not, especially in the repetitive behaviour domain. Regression was not associated to thimerosal exposure, indirectly estimated by year of birth.Conclusions  A loss of skill, present in one out of five children with PDD, is associated with a slightly more severe symptomatology as measured by the ADI‐R, particularly in the repetitive behaviours domain. Furthermore, although abnormalities are often noticed by the caregivers at the time of regression, the ADI‐R reveals that other atypical behaviours were in fact present prior to the onset of regression in most cases. None of the secondary factors investigated were associated with regression. In children unexposed to thimerosal‐containing vaccines, the rate of regression was similar to that reported in studies of samples exposed to thimerosal, suggesting that thimerosal has no specific association with regressive autism.
The ARGONAUTE10 gene modulates shoot apical meristem maintenance and establishment of leaf polarity by repressing miR165/166 in Arabidopsis
Authors: Liu Qili , Yao Xiaozhen , Pi Limin , Wang Hua , Cui Xiaofeng , Huang Hai 
Published: November 2008

SummaryThe shoot apical meristem (SAM) of angiosperms comprises a group of undifferentiated cells which divide to maintain the meristem and also give rise to all the above‐ground structures of the plant. Previous studies revealed that the Arabidopsis ARGONAUTE10 [AGO10, also called PINHEAD (PNH) or ZWILLE (ZLL)] gene is one of the critical SAM regulators, but the mechanism by which AGO10 modulates the SAM is unknown. In the present study we show that AGO10 genetically represses microRNA165/166 (miR165/166) for SAM maintenance as well as establishment of leaf adaxial–abaxial polarity. Levels of miR165/166 in leaves and embryonic SAMs of pnh/zll/ago10 mutants are abnormally elevated, leading to a reduction in the quantity of homeodomain‐leucine zipper (HD‐ZIP) III gene transcripts, the targets of miR165/166. This reduction is the primary cause of pnh/zll SAM and leaf defects, because the aberrant pnh/zll phenotypes were partially rescued by either increasing levels of HD‐ZIP III transcripts or decreasing levels of miR165/166 in the SAM and leaf. Furthermore, plants with an abnormal apex were more frequent among pnh/zll rdr6 and pnh/zll ago7 double mutants and increased levels of miR165/166 were detected in rdr6 apices. These results indicate that AGO10 and RDR6/AGO7 may act in parallel in modulating accumulation of miR165/166 for normal plant development.
Patients’ perceptions of safety if interpersonal continuity of care were to be disrupted
Authors: Pandhi Nancy , Schumacher Jessica , Flynn Kathryn E. , Smith Maureen 
Published: November 2008

AbstractObjective  To determine if patients vary in perceptions of safety if interpersonal continuity were to be disrupted. If so, which characteristics are associated with feeling unsafe?Background  The extent to which patients’ preference for continuity with a personal physician is due to perceptions of safety is unclear.Design  Observational study (Wisconsin Longitudinal Study Graduate and Sibling Survey).Setting and participants  A total of 6827 respondents (most aged 63–66 years) who completed the 2003–06 survey round.Main variables studied  Age, gender, marital status, education, health insurance type, illnesses, medications, length of relationship with provider and place, personality type, decision‐making preference and trust in physician deliberation.Main outcome measures  Safety perception when visiting another doctor or clinic if own doctor were not available.Results  Twelve percent of respondents felt unsafe. After adjustment, as compared to those who felt safe, those who felt unsafe were more likely to be women (Odds ratio = 1.65, 95% confidence interval = 1.35–2.01), have more chronic conditions (1.27, 1.08–1.50) and have a longer relationship with a usual provider: 5–9 years (1.53, 1.11–2.10) 10–14 years (1.41, 1.02–1.95) and 15 or more years (1.62, 1.20–2.17) compared to 0–4 years. Those who preferred active participation in decision making and had trust in their physician were less likely to feel safe (1.63, 1.10–2.41).Conclusions  Certain older adults perceive being unsafe if not seeing their usual physician. Further research should investigate reasons for perceptions of safety if continuity were disrupted and any implications for care.
Patient evaluations of accessibility and co‐ordination in general practice in Europe
Authors: Wensing Michel , Hermsen Jan , Grol Richard , Szecsenyi Joachim 
Published: November 2008

AbstractObjective  To determine whether patient evaluations of the accessibility to general practice and co‐ordination with other care providers were associated with characteristics of general practice organizations.Background  In 1998 patients across Europe perceived that small general practices have better accessibility than large practices. Since then a number of changes in primary care have had impact on accessibility and co‐ordination of care.Design, setting and participants  The study was based on data from the European Practice Assessment study, an observational study in 284 general practices in 10 countries in 2004.Main outcome measures  Patient evaluations of general practice were measured with the 23‐item Europep instrument, from which seven items on accessibility and co‐ordination were selected in a principal factor analysis. Six practice characteristics were examined: percentage of female general practitioners, mean age of physicians, mean number of physician hours worked per week, number of general practitioners, number of care providers, urbanization level. Mixed regression models were applied, in which patients were clustered within practices, and practices within countries.Results  Practices with a higher numbers of care providers received less positive patient evaluations (b = −0.112, P = 0.004). The other practice characteristics were not related to patient evaluations. Only a small proportion of the total variation in patient evaluations of accessibility and co‐ordination (1.8%) was explained by characteristics of the general practice organizations.Conclusions  General practices have become larger in most developed countries in recent years, but patients seemed to prefer general practice organizations with fewer health professionals.
Multiple glacial refugia and complex postglacial range shifts of the obligatory woodland plant Polygonatum verticillatum (Convallariaceae)
Authors: Kramp K. , Huck S. , Niketić M. , Tomović G. , Schmitt T. 
Published: November 2008

AbstractThe phylogeography of typical alpine plant species is well understood in Europe. However, the genetic patterns of boreo‐montane species are mostly unstudied. Therefore, we analysed the AFLPs of 198 individuals of Polygonatum verticillatum over a major part of its European distribution. We obtained a total of 402 reproducible fragments, of which 96.8% were polymorphic. The average ΦST over all samples was high (73.0%). The highest number of private fragments was observed in the Cantabrian Mountains; the highest genetic diversities of the populations were detected in populations from the Alps. BAPS, Principal Coordinates and Cluster analyses revealed a deep split between the Cantabrian population and all other samples. The latter further distinguished two major groups in western and eastern Europe. These results suggest a complex biogeographical history of P. verticillatum. The Cantabrian population was most probably isolated for the longest time. Furthermore, putative glacial survival centres might have existed in the western group around the glaciated Alps and in the eastern group in the foothills of the Carpathian and Balkan mountain systems. The origin of the Scandinavian populations is still unresolved, but an origin from the southeastern Alps or the western Balkans appears the most likely scenario.
Morphological variation in the flowers of Jacaratia mexicana A. DC. (Caricaceae), a subdioecious tree
Authors: Aguirre A. , Vallejo‐Marín M. , Piedra‐Malagón E. M. , Cruz‐Ortega R. , Dirzo R. 
Published: November 2008

AbstractThe Caricaceae is a small family of tropical trees and herbs in which most species are dioecious. In the present study, we extend our previous work on dioecy in the Caricaceae, characterising the morphological variation in sexual expression in flowers of the dioecious tree Jacaratia mexicana. We found that, in J. mexicana, female plants produce only pistillate flowers, while male plants are sexually variable and can bear three different types of flowers: staminate, pistillate and perfect. To characterise the distinct types of flowers, we measured 26 morphological variables. Our results indicate that: (i) pistillate flowers from male trees carry healthy‐looking ovules and are morphologically similar, although smaller than, pistillate flowers on female plants; (ii) staminate flowers have a rudimentary, non‐functional pistil and are the only flowers capable of producing nectar; and (iii) perfect flowers produce healthy‐looking ovules and pollen, but have smaller ovaries than pistillate flowers and fewer anthers than staminate flowers, and do not produce nectar. The restriction of sexual variation to male trees is consistent with the evolutionary path of dioecy from hermaphrodite ancestors through the initial invasion of male‐sterile plants and a subsequent gradual reduction in female fertility in cosexual individuals (gynodioecy pathway), but further work is needed to confirm this hypothesis.
The effect of tibia morphology on vector competency of mushroom sciarid flies
Authors: Shamshad A. , Clift A. D. , Mansfield S. 
Published: November 2008

AbstractMushroom sciarid flies Lycoriella ingenua (Dufour) and Bradysia ocellaris (Comstock) are major pests of cultivated mushrooms, Agaricus bisporus (Lange) Imbach. The economic threshold of these pests is very low because they vector pathogens across mushroom beds, e.g. Verticillium fungicola which causes ‘dry bubble’ disease. Under controlled conditions, B. ocellaris transported more V. fungicola spores than L. ingenua from infected to sterile culture plates. Similar results were obtained when L. ingenua and B. ocellaris were collected from a growing room infected with V. fungicola then introduced onto sterile culture plates for 90 min. The external morphology of B. ocellaris and L. ingenua was examined using scanning electron microscopy. The micrographs showed clusters of V. fungicola spores attached to the inner side of a comb‐like row of bristles on the fore tibia of B. ocellaris whereas L. ingenua does not possess an equivalent structure on the fore tibia. These morphological differences are the most probable explanation for the greater competence of B. ocellaris as a vector of V. fungicola compared with L. ingenua.