bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nanoscale imaging in DNA nanotechnology
Authors: Jungmann Ralf , Scheible Max , Simmel Friedrich C. 
Published: November 2011

AbstractDNA nanotechnology has developed powerful techniques for the construction of precisely defined molecular structures and machines, and nanoscale imaging methods have always been crucial for their experimental characterization. While initially atomic force microscopy (AFM) was the most widely employed imaging method for DNA‐based molecular structures, in recent years a variety of other techniques were adopted by researchers in the field, namely electron microscopy (EM), super‐resolution fluorescence microscopy, and high‐speed AFM. EM is now typically applied for the characterization of compact nanoobjects and three‐dimensional (3D) origami structures, as it offers better resolution than AFM and can be used for 3D reconstruction from single‐particle analysis. While the small size of DNA nanostructures had previously precluded the application of fluorescence microscopic methods, the development of super‐resolution microscopy now facilities the application of fast and powerful optical methods also in DNA nanotechnology. In particular, the observation of dynamical processes associated with DNA nanoassemblies—e.g., molecular walkers and machines—requires imaging techniques that are both fast and allow observation under native conditions. Here single‐molecule fluorescence techniques and high‐speed AFM are beginning to play an increasingly important role. WIREs Nanomed Nanobiotechnol 2012, 4:66–81. doi: 10.1002/wnan.173This article is categorized under:

Nanotechnology Approaches to Biology > Nanoscale Systems in Biology
Atorvastatin reduces vascular endothelial growth factor (VEGF) expression in human non‐small cell lung carcinomas (NSCLCs) via inhibition of reactive oxygen species (ROS) production
Authors: Chen Jie , Liu Bing , Yuan Jiayi , Yang Jie , Zhang Jingjie , An Yu , Tie Lu , Pan Yan , Li Xuejun 
Published: November 2011

The high metastatic potential of non‐small cell lung cancers (NSCLCs) is closely correlated with the elevated expression of vascular endothelial growth factor (VEGF) and resultant tumor angiogenesis. However, no effective strategies against VEGF expression have been available in NSCLCs therapy. This study demonstrated that elevated reactive oxygen species (ROS) levels derived from both mitochondria and NADPH oxidase were required for VEGF expression in NSCLC cells. Atorvastatin administration could significantly inhibit VEGF expression both in vitro and in vivo via inhibition of ROS production. Atorvastatin inhibited ROS generation partly through suppression of Rac1/NADPH oxidase activity. Specifically, atorvastatin could upregulate the activity of glutathione peroxidase (GPx) and catalase, which are responsible for elimination of hydrogen peroxide (H2O2) in the mitochondria and peroxisomes, respectively. Thus, inhibition of ROS production by concomitant suppression of Rac1/NADPH oxidase activity and upregulation of the activity of GPx and catalase contributes critically to atorvastatin‐reduced VEGF expression in NSCLCs. Atorvastatin may be a potential alternative against VEGF expression and angiogenesis in NSCLCs therapy.
Involvement of interleukin‐1β mediated nuclear factor κB signalling pathways to down‐regulate prostate‐specific antigen and cell proliferation in LNCaP prostate cancer cells
Authors: Bouraoui Yosra , Rais Nawfel Ben , Culig Zoran , Oueslati Ridha 
Published: November 2011

AbstractInvolvement of NF‐κB (nuclear factor κB) mediated by IL‐1β (interleukin‐1β) on cell proliferation and PSA (prostate‐specific antigen) production of LNCaP prostate cell lines and the possible cross‐talk with Akt (also known as protein kinase B) signalling pathway has been investigated. NF‐κB and Akt were analysed by Western blotting from LNCaP cells treated by IL‐1β before proliferation and PSA production were measured. IL‐1β inhibited proliferation and decreased PSA production. The Akt pathway was not sensitive, whereas NF‐κB phosphorylation occurred as a result of treatment. PSA production and proliferation of LNCaP cells were down‐regulated by NF‐κB mediated by IL‐1β promoting anti‐apoptotic signalling and co‐suppressor factors of PSA expression. IL‐1β through NF‐κB activation provides a rationale for therapeutic approaches in the anticancer treatment of prostate.
T regulatory cells in B‐cell malignancy – tumour support or kiss of death?
Authors: Lindqvist Camilla A. , Loskog Angelica S. I. 
Published: November 2011

SummaryIt is well established that T regulatory (Treg) cells counteract tumour immunity. However, conflicting results describing the role of Treg cells in haematological tumours warrant further investigations to clarify the interactions between Treg cells and the tumour. B‐cell malignancy derives from different stages of B‐cell development and differentiation in which T cells play a profound role. The transformed B cell may still be in need of T‐cell help to thrive but simultaneously they may be recognized and destroyed by cytotoxic lymphocytes. Recent reports demonstrate that Treg cells can suppress and even kill B cells as part of their normal function to rescue the body from autoimmunity. An emerging body of evidence points out that Treg cells not only inhibit tumour‐specific T cells but may also have a role in suppressing the progression of the B‐cell tumour. In this review, we discuss the origin and function of Treg cells and their role in patients with B‐cell tumours.
Influence of salt concentration on properties of marinated meat from fresh and frozen herring (Clupea harengus L.)
Authors: Szymczak Mariusz , Kołakowski Edward , Felisiak Katarzyna 
Published: November 2011

SummarySalt concentrations of brine above 10% are still commonly used in fish marinating process. The study has showed an increasing salt concentrations affect to adversely all the properties of marinated herring meat. Increase in salt concentration from 5% to 15% resulted in significantly (P < 0.05) decrease content of water, non‐protein nitrogen and products of protein hydrolysis. Consequently, weight yield of marinated fresh herring decreased from 83% to 74%. The most palatable marinades contained 2–3% NaCl in meat only. The higher salt concentrations applied significantly (P < 0.05) worsened the taste, texture and colour of marinated herring. Texture profile analyses (TPA), free hydroxyproline content and colour analyses (L*a*b) confirmed the negative influence of high salt concentration on the marinades quality. Frozen and thawed herring tissue showed greater sensitivity to salt. Namely, marinades from frozen fish contained by 0.3 more salt (P < 0.05), and the weight yield was by 2.3–10.3 percent point lower than from the fresh herring. Meat from frozen herring when matured has significantly (P < 0.05) lower sensory value, lower content of protein hydrolysis products, free hydroxyproline and higher parameter b* value of than the fresh one.
Warming effects on consumption and intraspecific interference competition depend on predator metabolism
Authors: Lang Birgit , Rall Björn C. , Brose Ulrich 
Published: November 2011

Summary1. Model analyses show that the stability of population dynamics and food web persistence increase with the strength of interference competition. Despite this critical importance for community stability, little is known about how external factors such as the environmental temperature affect intraspecific interference competition.2. We aimed to fill this void by studying the functional responses of two ground beetle species of different body size, Pterostichus melanarius and Poecilus versicolor. These functional response experiments were replicated across four predator densities and two temperatures to address the impact of temperature on intraspecific interference competition.3. We generally expected that warming should increase the speed of movement, encounter rates and in consequence interference among predator individuals. In our experiment, this expectation was supported by the results obtained for the larger predator, P. melanarius, whereas the opposite pattern characterized the interference behaviour of the smaller predator P. versicolor.4. These results suggest potentially nontrivial implications for the effects of environmental temperature on intraspecific interference competition, for which we propose an explanation based on the different sensitivity to warming of metabolic rates of both species. As expected, increasing temperature led to stronger interference competition of the larger species, P. melanarius, which exhibited a weaker increase in metabolic rate with increasing temperature. The stronger increase in the metabolic rate of the smaller predator, P. versicolor, had to be compensated by increasing searching activity for prey, which did not leave time for increasing interference.5. Together, these results suggest that any generalization how interference competition responds to warming should also take the species’ metabolic response to temperature increases into account.
Validation of reflex indicators for measuring vitality and predicting the delayed mortality of wild coho salmon bycatch released from fishing gears
Authors: Raby Graham D. , Donaldson Michael R. , Hinch Scott G. , Patterson David A. , Lotto Andrew G. , Robichaud David , English Karl K. , Willmore William G. , Farrell Anthony P. , Davis Michael W. , Cooke Steven J. 
Published: November 2011

Summary1. Effective management of fish and wildlife populations benefits from an understanding of the effects of stressors on individual physiology. While physiological knowledge can provide a mechanistic understanding of organismal responses, its applied utility is limited because it cannot easily be used by stakeholders.2. Reflex action mortality predictors (RAMP) is a method that involves checking for the presence or absence of natural animal reflexes to generate a condition (RAMP) score in response to stressors and to predict fate. The method has previously been validated with fishes in artificial laboratory‐ and field‐based holding studies as a responsive measure of fisheries capture stress and a predictor of delayed mortality, but has not been evaluated in the wild.3. We used radio telemetry to monitor migration success of 50 endangered coho salmon Oncorhynchus kisutch following incidental capture in an aboriginal beach seine fishery in the lower Fraser River (Canada). RAMP was used to measure the condition of fish at release and to predict migration success following capture. Biopsy of an additional 43 coho profiled physiological condition at time of release.4. Individuals with greater reflex impairment (higher RAMP scores) at release experienced significantly higher rates of migration failure. RAMP scores were also significantly correlated with fishery handling time. Plasma variables showed that captured coho had experienced physiological stress characteristic of exhaustive exercise and hypoxia, with significantly elevated cortisol and lactate values for fish entangled longer in fishing gear.5. Synthesis and applications. This is the first validation of RAMP in a wild setting. Based on our findings, fishers could use the method and make adjustments in fishing behaviour in real‐time to improve fish condition and reduce the mortality of bycatch, and conservation practitioners could monitor animal condition and identify problems that deserve management attention. RAMP is an easy, rapid and inexpensive approach to predicting mortality and measuring vitality and performed better than traditional physiological tools that cannot easily be used by stakeholders.
Combined transcriptome, genetic diversity and metabolite profiling in tomato fruit reveals that the ethylene response factor SlERF6 plays an important role in ripening and carotenoid accumulation
Authors: Lee Je Min , Joung Je‐Gun , McQuinn Ryan , Chung Mi‐Young , Fei Zhangjun , Tieman Denise , Klee Harry , Giovannoni James 
Published: November 2011

SummarySolanum lycopersicum (tomato) and its wild relatives harbor genetic diversity that yields heritable variation in fruit chemistry that could be exploited to identify genes regulating their synthesis and accumulation. Carotenoids, for example, are essential in plant and animal nutrition, and are the visual indicators of ripening for many fruits, including tomato. Whereas carotenoid synthesis is well characterized, factors regulating flux through the pathway are poorly understood at the molecular level. To exploit the impact of tomato genetic diversity on carotenoids, Solanum pennellii introgression lines were used as a source of defined natural variation and as a resource for the identification of candidate regulatory genes. Ripe fruits were analyzed for numerous fruit metabolites and transcriptome profiles generated using a 12 000 unigene oligoarray. Correlation analysis between carotenoid content and gene expression profiles revealed 953 carotenoid‐correlated genes. To narrow the pool, subnetwork analysis of carotenoid‐correlated transcription revealed 38 candidates. One candidate for impact on trans‐lycopene and β‐carotene accumulation was functionally charaterized, SlERF6, revealing that it indeed influences carotenoid biosynthesis and additional ripening phenotypes. Reduced expression of SlERF6 by RNAi enhanced both carotenoid and ethylene levels during fruit ripening, demonstrating an important role for SlERF6 in ripening, integrating the ethylene and carotenoid synthesis pathways.
Does Competition Affect Schools' Performance? Evidence from Italy through OECD‐PISA Data
Authors: Agasisti Tommaso 
Published: November 2011

This article evaluates the impact of competition on the performance of Italian schools. The study is based on policy experiments developed in 2000 by the Lombardy Regional government which introduced a voucher plan to encourage families to enrol their children in private schools. After this intervention, many other Regions launched similar policies. Despite the high political attention to this theme in Italy, there is almost no economic research on the possible role of such policies in fostering competition, and on the effects of competition on schools’ outputs.As there are not data collected by the Italian authorities for the purpose, the article uses the OECD‐PISA 2006 dataset with some additional administrative information.The empirical analysis shows that while some indicators of school competition have been found significant in – positively – affecting schools’ performances (in terms of student achievement), there is not strong evidence that voucher policies implemented in the Lombardy Region did improve school competition.
Evaluation of the quality of an online geocoding resource in the context of a large Brazilian city
Authors: Davis Jr. Clodoveu A. , de Alencar Rafael Odon 
Published: November 2011

AbstractGeocoding urban addresses usually requires the use of an underlying address database. Under the influence of the format defined for TIGER files decades ago, most address databases and street geocoding algorithms are organized around street centerlines, associating numbering ranges to thoroughfare segments between two street crossings. While this method has been successfully employed in the USA for a long time, its transposition to other countries may lead to increased errors. This article presents an evaluation of the centerline‐geocoding resources provided by Google Maps, as compared to the point‐geocoding method used in the city of Belo Horizonte, Brazil, which we took as a baseline. We generated a textual address for each point object found in the city's point‐based address database, and submitted it to the Google Maps geocoding API. We then compared the resulting coordinates with the ones recorded in Belo Horizonte's GIS. We demonstrate that the centerline segment interpolation method, employed by the online resources following the American practice, has problems that can considerably influence the quality of the geocoding outcome. Completeness and accuracy have been found to be irregular, especially within lower income areas. Such errors in online services can have a significant impact on geocoding efforts related to social applications, such as public health and education, since the online service can be faulty and error‐prone in the most socially demanding areas of the city. In the conclusion, we point out that a volunteered geographic information (VGI) approach can help with the enrichment and enhancement of current geocoding resources, and can possibly lead to their transformation into more reliable point‐based geocoding services.
Inferring the Location of Twitter Messages Based on User Relationships
Authors: Davis Jr. Clodoveu A. , Pappa Gisele L. , de Oliveira Diogo Rennó Rocha , de L. Arcanjo Filipe 
Published: November 2011

AbstractUser interaction in social networks, such as Twitter and Facebook, is increasingly becoming a source of useful information on daily events. The online monitoring of short messages posted in such networks often provides insight on the repercussions of events of several different natures, such as (in the recent past) the earthquake and tsunami in Japan, the royal wedding in Britain and the death of Osama bin Laden. Studying the origins and the propagation of messages regarding such topics helps social scientists in their quest for improving the current understanding of human relationships and interactions. However, the actual location associated to a tweet or to a Facebook message can be rather uncertain. Some tweets are posted with an automatically determined location (from an IP address), or with a user‐informed location, both in text form, usually the name of a city. We observe that most Twitter users opt not to publish their location, and many do so in a cryptic way, mentioning non‐existing places or providing less specific place names (such as “Brazil”). In this article, we focus on the problem of enriching the location of tweets using alternative data, particularly the social relationships between Twitter users. Our strategy involves recursively expanding the network of locatable users using following‐follower relationships. Verification is achieved using cross‐validation techniques, in which the location of a fraction of the users with known locations is used to determine the location of the others, thus allowing us to compare the actual location to the inferred one and verify the quality of the estimation. With an estimate of the precision of the method, it can then be applied to locationless tweets. Our intention is to infer the location of as many users as possible, in order to increase the number of tweets that can be used in spatial analyses of social phenomena. The article demonstrates the feasibility of our approach using a dataset comprising tweets that mention keywords related to dengue fever, increasing by 45% the number of locatable tweets.
Participation, characteristics and retention rates of HIV‐positive immigrants in the Swiss HIV Cohort Study*
Authors: Thierfelder C , Weber R , Elzi L , Furrer H , Cavassini M , Calmy A , Bernasconi E , Gutmann C , Ledergerber B ,   the Swiss HIV Cohort Study Group
Published: November 2011

ObjectiveData from observational cohorts may be influenced by population structure and loss to follow‐up (LTFU). Quality of care may be associated with participation in cohort networks. We aimed to study the participation, characteristics and retention rates of immigrants in the Swiss HIV Cohort Study (SHCS).MethodsWe compared enrolment over time (1996–1999, 2000–2003 and 2004–2008) and LTFU between individuals from different geographical regions. In 2008, we performed a cross‐sectional survey to investigate the proportion of individuals not participating in the SHCS but who were in care at SHCS institutions. Predictors for LTFU were analysed using Cox proportional hazard models, and those for nonparticipation using logistic regression.ResultsA total of 7840 individuals entered the SHCS during the observation period. The proportion of immigrants increased over time, especially the proportion of women from sub‐Saharan Africa, which increased from 21 to 48% during the observation period. Overall LTFU was 3.76 [95% confidence interval (CI) 3.58–3.95]/100, with the highest hazard ratio in men from sub‐Saharan Africa (2.82/100 patient‐years; 95% CI 2.30–3.46/100), compared with men from northwestern countries. Other predictors for LTFU were age <30 years, lower education, injecting drug use, and higher baseline CD4 cell counts. Participants taking antiretroviral therapy had reduced LTFU. The survey showed that 84% of HIV‐infected patients in care at SHCS institutions were enrolled in the cohort. Nonparticipation was more likely among men from non‐European regions (odds ratio 2.73; 95% CI 2.29–3.24), women from sub‐Saharan Africa (odds ratio 3.01; 95% CI 2.40–3.77) and women from Latin America/Caribbean (odds ratio 2.10; 95% CI 1.30–3.39).ConclusionsNumbers of HIV‐infected immigrants are increasing but they are underrepresented in the SHCS, and immigrants are more likely to be lost to follow‐up.
Artistic Urbanization: Creative Industries and Creative Control in Beijing
Authors: REN XUEFEI , SUN MENG 
Published: November 2011

AbstractThe discourse of creative industries arrived in China in the early 2000s via the epistemic network of international scholars and consultants. It has since garnered enthusiastic support on the domestic policy circuit, where it is viewed as the key to making the transition from ‘Made in China’ to ‘Created in China’. This article situates China's creative industry development in its urban context, examining the state spatial strategies of reconstituting control over cultural production by turning the formerly organic artist villages into official art districts. Drawing upon fieldwork on the visual and performing arts sectors in Beijing, we find that the local state has extended its creative control over artists by using interlocking directorates — a practice of appointing the same government officials to serve across the executive boards of multiple governing organizations in art districts. The districtification of artist villages has led to ‘artistic urbanization’, a process whereby rural villages quickly urbanize in the midst of art‐led development endorsed and monitored by the local state. Artistic urbanization is a spatial strategy by the state to reconstitute its control over cultural production and to profit from real estate development, and it has led to renewed censorship of artists and widespread property speculation.RésuméLe discours des industries créatives a été amené en Chine au début des années 2000 par le réseau épistémique des chercheurs et des consultants internationaux. Depuis, il a gagné un appui enthousiaste dans les circuits de politique intérieure où on le considère comme la clé de la transition du ‘Fabriqué’ au ‘Créé’ en Chine. Cet article replace l’essor de l’industrie créative chinoise dans son contexte urbain, en s’attachant aux stratégies spatiales de l’État, lequel cherche à recontrôler la production culturelle en transformant d’anciens villages d’artistes organiques en quartiers d’art officiels. À partir d’un travail de terrain sur les arts visuels et du spectacle à Beijing, il apparaît que l’État local a étendu son contrôle de la créativité artistique en ‘croisant’ les conseils d’administration, par la nomination des mêmes représentants gouvernementaux comme administrateurs dans de nombreux organismes régissant les quartiers artistiques. La redéfinition des villages d’artistes en quartiers a entraîné une ‘urbanisation artistique’ rapide de villages ruraux dans le cadre d’un aménagement autour des arts, validé et piloté par l’État local. L’urbanisation artistique est une stratégie spatiale pour que l’État récupère son contrôle de la production culturelle et tire parti de l’essor immobilier. Elle a conduit à un regain de censure artistique et à une vaste spéculation foncière.