bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterisation of DDT and Pyrethroid Resistance in Trinidad and Tobago populations ofAedes aegypti
Authors: Polson K.A. , Rawlins S.C. , Brogdon W.G. , Chadee D.D. 
Published: January 2011

AbstractInsecticide resistance is an important factor in the effectiveness ofAedes aegypticontrol and the related spread of dengue. The objectives of this study were to investigate the status of the organochlorine dichlorodiphenyltrichloroethane (DDT) and pyrethroid (permethrin and deltamethrin) resistance in Trinidad and Tobago populations ofAe. aegyptiand the underlying biochemical mechanisms. Nine populations ofAe. aegyptilarvae from Trinidad and Tobago were assayed to DDT and PYs using the Centers for Disease Control and Prevention (CDC) time-mortality-based bioassay method. A diagnostic dosage (DD) was established for each insecticide using the CAREC reference susceptibleAe. aegyptistrain and a resistance threshold (RT), time in which 98–100% mortality was observed in the CAREC strain, was calculated for each insecticide. Mosquitoes which survived the DD and RT were considered as resistant, and the resistance status of each population was categorised based on the WHO criteria with mortality <80% indicative of resistance. Biochemical assays were conducted to determine the activities of α and β esterases, mixed function oxidases (MFO) and glutathione-S-transferases (GST) enzymes which are involved in resistance of mosquitoes to DDT and PYs. Enzymatic activity levels in each population were compared with those obtained for the CAREC susceptible strain, and significant differences were determined by Kruskal-Wallis and Tukey's non-parametric tests (P<0.05). The established DDs were 0.01 mg l−1, 0.2 mg l−1and 1.0 mg l−1for deltamethrin, permethrin and DDT, respectively; and the RTs for deltamethrin, permethrin and DDT were 30, 75 and 120 min, respectively. AllAe. aegyptipopulations were resistant to DDT (<80% mortality); two strains were incipiently resistant to deltamethrin and three to permethrin (80–98% mortality). Biochemical assays revealed elevated levels of α-esterase and MFO enzymes in allAe. aegyptipopulations. All, except three populations, showed increased levels of β-esterases; and all populations, except Curepe, demonstrated elevated GST levels.Metabolic detoxification of enzymes is correlated with the manifestation of DDT and PY resistance in Trinidad and Tobago populations ofAe. aegypti.The presence of this resistance also suggests that knock down (kdr)-type resistance may be involved, hence the need for further investigations. This information can contribute to the development of an insecticide resistance surveillance programme and improvement of resistance management strategies aimed at combatting the spread of dengue in Trinidad and Tobago.
Soil organic carbon dynamics and crop yield for different crop rotations in a degraded ferruginous tropical soil in a semi-arid region: a simulation approach
Authors: SOLER C. M. TOJO , BADO V. B. , TRAORE K. , BOSTICK W. MCNAIR , JONES J. W. , HOOGENBOOM G. 
Published: January 2011

SUMMARYIn recent years, simulation models have been used as a complementary tool for research and for quantifying soil carbon sequestration under widely varying conditions. This has improved the understanding and prediction of soil organic carbon (SOC) dynamics and crop yield responses to soil and climate conditions and crop management scenarios. The goal of the present study was to estimate the changes in SOC for different cropping systems in West Africa using a simulation model. A crop rotation experiment conducted in Farakô-Ba, Burkina Faso was used to evaluate the performance of the cropping system model (CSM) of the Decision Support System for Agrotechnology Transfer (DSSAT) for simulating yield of different crops. Eight crop rotations that included cotton, sorghum, peanut, maize and fallow, and three different management scenarios, one without N (control), one with chemical fertilizer (N) and one with manure applications, were studied. The CSM was able to simulate the yield trends of various crops, with inconsistencies for a few years. The simulated SOC increased slightly across the years for the sorghum–fallow rotation with manure application. However, SOC decreased for all other rotations except for the continuous fallow (native grassland), in which the SOC remained stable. The model simulated SOC for the continuous fallow system with a high degree of accuracy normalized root mean square error (RMSE)=0·001, while for the other crop rotations the simulated SOC values were generally within the standard deviation (s.d.) range of the observed data. The crop rotations that included a supplemental N-fertilizer or manure application showed an increase in the average simulated aboveground biomass for all crops. The incorporation of this biomass into the soil after harvest reduced the loss of SOC. In the present study, the observed SOC data were used for characterization of production systems with different SOC dynamics. Following careful evaluation of the CSM with observed soil organic matter (SOM) data similar to the study presented here, there are many opportunities for the application of the CSM for carbon sequestration and resource management in Sub-Saharan Africa.
Current use of and attitudes to e-learning in otolaryngology: questionnaire survey of UK otolaryngology trainees
Authors: Fraser L , Gunasekaran S , Mistry D , Ward V M M 
Published: January 2011

AbstractIntroduction:The E-lefENT programme is a collaborative e-learning project developed by the Department of Health and ENTUK. Prior to its introduction, we aimed to assess current use of and attitudes towards e-learning amongst UK otolaryngology trainees.Method:A web-based questionnaire was distributed to UK otolaryngology trainees via regional programme directors.Results:A total of 117 responses was received (35 per cent response rate). Most trainees reported increasing exposure to e-learning throughout their training and rated their current computer literacy skills highly, although satisfaction with current e-learning resources was found to vary widely for a variety of reasons.Conclusion:Meeting the educational needs of otolaryngology trainees in the current era continues to be a challenge. Most trainees are already familiar with e-learning, although the quality and delivery of available websites is currently variable. The majority of trainees who responded seemed receptive to the implementation of a free, otolaryngology-specific e-learning resource.
Immune-mediated pathology of nematode infection in sheep – is immunity beneficial to the animal?
Authors: WILLIAMS ANDREW R. 
Published: January 2011

SUMMARYNematode parasitism is a severe impediment to sustainable and profitable sheep production in many countries in the world. Parasite resistance to anthelmintic treatment and consumer demand for organic agricultural products has led to much research into harnessing natural immunity as a long-term control measure. However, there is evidence that many of the clinical signs of nematode infection in sheep are due to immune-mediated pathology rather than direct effects of the parasite. Therefore, the desirability of promoting a strong natural immunity in sheep has been questioned. This review attempts to clarify some of the arguments for and against promoting strong natural immunity, particularly through selective breeding of parasite-resistant animals. It is concluded that the detrimental effects of immune-mediated pathology are outweighed by epidemiological and welfare benefits. Thus, control of nematode parasites through selection of naturally resistant sheep is a sustainable and desirable objective.
The changing occurrences of tetralogy of Fallot and simple transposition of the great arteries in Southern Nevada
Authors: Evans William N. , Acherman Ruben J. , Castillo William J. , Restrepo Humberto 
Published: January 2011

AbstractWe analysed the occurrence of tetralogy of Fallot and simple transposition in the Hispanic and non-Hispanic populations of Clark County, Nevada, in the United States of America over a 30-year period from 1980 to 2009. We found a downward trend in the incidence of simple transposition of the great arteries in the non-Hispanic population but an upward trend in the incidence in the Hispanic population. For tetralogy of Fallot, we found an upward trend in the incidence in both populations; the trend, however, was more dramatic in the Hispanic population. We also noted differences in the male to female ratios in the different groups. Even though we make no definitive conclusions regarding the causes of these incidence curves or the differences in occurrence between males or females, the data suggest an interplay of genetics and the environment.
Consumer segmentation based on the level and structure of fruit and vegetable intake: an empirical evidence for US adults from the National Health and Nutrition Examination Survey (NHANES) 2005–2006
Authors: Demydas Tetyana 
Published: January 2011

AbstractObjectiveTo identify consumption patterns of fruit and vegetables within a representative sample of US adults with a focus on degree of produce processing and to explore sociodemographic, lifestyle and nutritional profiles associated with these patterns.DesignCross-sectional analysis. Fruit and vegetable (F&V) consumption data were collected using two non-consecutive 24 h recalls. For the purpose of the study, F&V intakes were aggregated into seven subgroups indicating degree of processing, which afterwards were used as inputs into cluster analysis.SettingThe 2005–2006 National Health and Nutrition Examination Survey.SubjectsThe sample consisted of 2444 adults aged 20–59 years.ResultsTotal average F&V intake of the adults was below the recommended level. Thereby, 20 % of the respondents consumed fruit only in the form of juice. Three F&V consumption patterns were identified: ‘low-intake F&V consumers’ (74 % of respondents), ‘consumers of healthier F&V options’ (13 %) and ‘intensive fruit juice consumers’ (13 %). These groups differed markedly in terms of their sociodemographic, lifestyle and health characteristics, such as gender, age, race/ethnicity, education, smoking, weight status, etc. Differences in nutrient profiles were also found, with the ‘consumers of healthier F&V options’ showing better nutritional quality compared with other clusters.ConclusionsOnly a small share of US adults combines high F&V intakes with healthier F&V options that lead to a better nutritional profile. This raises discussion about a need to deliver more specific F&V promotion messages, including advice on healthier preparation methods, especially for the specific population groups.
Recovering key biological constituents through sparse representation of gene expression
Authors: Prat Yosef , Fromer Menachem , Linial Nathan , Linial Michal 
Published: January 2011

Abstract
Motivation: Large-scale RNA expression measurements are generating enormous quantities of data. During the last two decades, many methods were developed for extracting insights regarding the interrelationships between genes from such data. The mathematical and computational perspectives that underlie these methods are usually algebraic or probabilistic.
Results: Here, we introduce an unexplored geometric view point where expression levels of genes in multiple experiments are interpreted as vectors in a high-dimensional space. Specifically, we find, for the expression profile of each particular gene, its approximation as a linear combination of profiles of a few other genes. This method is inspired by recent developments in the realm of compressed sensing in the machine learning domain. To demonstrate the power of our approach in extracting valuable information from the expression data, we independently applied it to large-scale experiments carried out on the yeast and malaria parasite whole transcriptomes. The parameters extracted from the sparse reconstruction of the expression profiles, when fed to a supervised learning platform, were used to successfully predict the relationships between genes throughout the Gene Ontology hierarchy and protein–protein interaction map. Extensive assessment of the biological results shows high accuracy in both recovering known predictions and in yielding accurate predictions missing from the current databases. We suggest that the geometrical approach presented here is suitable for a broad range of high-dimensional experimental data.
Contact: michall@cc.huji.ac.il
Supplementary information: Supplementary data are available at Bioinformatics online.
Computational inference of grammars for larger-than-gene structures from annotated gene sequences
Authors: Tsafnat Guy , Schaeffer Jaron , Clayphan Andrew , Iredell Jon R. , Partridge Sally R. , Coiera Enrico 
Published: January 2011

Abstract
Motivation: Larger than gene structures (LGS) are DNA segments that include at least one gene and often other segments such as inverted repeats and gene promoters. Mobile genetic elements (MGE) such as integrons are LGS that play an important role in horizontal gene transfer, primarily in Gram-negative organisms. Known LGS have a profound effect on organism virulence, antibiotic resistance and other properties of the organism due to the number of genes involved. Expert-compiled grammars have been shown to be an effective computational representation of LGS, well suited to automating annotation, and supporting de novo gene discovery. However, development of LGS grammars by experts is labour intensive and restricted to known LGS.
Objectives: This study uses computational grammar inference methods to automate LGS discovery. We compare the ability of six algorithms to infer LGS grammars from DNA sequences annotated with genes and other short sequences. We compared the predictive power of learned grammars against an expert-developed grammar for gene cassette arrays found in Class 1, 2 and 3 integrons, which are modular LGS containing up to 9 of about 240 cassette types.
Results: Using a Bayesian generalization algorithm our inferred grammar was able to predict &gt; 95% of MGE structures in a corpus of 1760 sequences obtained from Genbank (F-score 75%). Even with 100% noise added to the training and test sets, we obtained an F-score of 68%, indicating that the method is robust and has the potential to predict de novo LGS structures when the underlying gene features are known.
Availability: http://www2.chi.unsw.edu.au/attacca.
Contact: guyt@unsw.edu.au
Multiple effects of benzamide antibiotics on FtsZ function
Authors: Adams David W. , Wu Ling Juan , Czaplewski Lloyd G. , Errington Jeff 
Published: January 2011

SummaryCell division in almost all bacteria is orchestrated by the essential tubulin homologue FtsZ, which assembles into a ring‐like structure and acts as a scaffold for the division machinery. Division was recently validated as an important target for antibiotics by the demonstration that low‐molecular‐weight inhibitors of FtsZ, called benzamides, can cure mice infected with Staphylococcus aureus. In treated cells of Bacillus subtilis we show that FtsZ assembles into foci throughout the cell, including abnormal locations at the cell poles and over the nucleoid. These foci are not inactive aggregates because they remain dynamic, turning over almost as rapidly as untreated polymers. Remarkably, although division is completely blocked, the foci efficiently recruit division proteins that normally co‐assemble with FtsZ. However, they show no affinity for components of the Min or Nucleoid occlusion systems. In vitro, the benzamides strongly promote the polymerization of FtsZ, into hyperstable polymers, which are highly curved. Importantly, even at low concentrations, benzamides transform the structure of the Z ring, resulting in abnormal helical cell division events. We propose that benzamides act principally by promoting an FtsZ protomer conformation that is incompatible with a higher‐order level of assembly needed to make a division ring.
Temporal matching among diurnal photosynthetic patterns within the crown of the evergreen sclerophyll Olea europaea L.
Authors: GRANADO‐YELA C. , GARCÍA‐VERDUGO C. , CARRILLO K. , RUBIO DE CASAS R. , KLECZKOWSKI L. A. , BALAGUER L. 
Published: January 2011

ABSTRACTTrees are modular organisms that adjust their within‐crown morphology and physiology in response to within‐crown light gradients. However, whether within‐plant variation represents a strategy for optimizing light absorption has not been formally tested. We investigated the arrangement of the photosynthetic surface throughout one day and its effects on the photosynthetic process, at the most exposed and most sheltered crown layers of a wild olive tree (Olea europaea L.). Similar measurements were made for cuttings taken from this individual and grown in a greenhouse at contrasted irradiance‐levels (100 and 20% full sunlight). Diurnal variations in light interception, carbon fixation and carbohydrate accumulation in sun leaves were negatively correlated with those in shade leaves under field conditions when light intensity was not limiting. Despite genetic identity, these complementary patterns were not found in plants grown in the greenhouse. The temporal disparity among crown positions derived from specialization of the photosynthetic behaviour at different functional and spatial scales: architectural structure (crown level) and carbon budget (leaf level). Our results suggest that the profitability of producing a new module may not only respond to construction costs or light availability, but also rely on its spatio‐temporal integration within the productive processes at the whole‐crown level.
Majocchi's granuloma in solid organ transplant recipients
Authors: Romero F.A. , Deziel P.J. , Razonable R.R. 
Published: January 2011

F.A. Romero, P.J. Deziel, R.R. Razonable. Majocchi's granuloma in solid organ transplant recipients. Transpl Infect Dis 2011: 13: 424–432. All rights reservedAbstract: Superficial fungal infections are fairly prevalent in transplant recipients and the incidence increases with more intense graft‐conserving immunosuppressive therapy. Majocchi's granuloma is a deep folliculitis caused by dermatophytes that involves deeper layers of the dermis. Only a few case reports of the condition have been documented in transplant recipients. After an extensive review of the medical literature, 21 cases were retrieved and are summarized here, together with a new case that occurred in a recent heart transplant recipient from our institution. This report aims to provide a comprehensive analysis of Majocchi's granuloma in solid organ transplant (SOT) recipients, with special focus on potential risk factors, offending pathogens, clinical presentation, therapeutic approaches, and outcome. General observations are presented emphasizing the relevance of close clinical and dermatologic follow‐up in high‐risk SOT patients with specific comments regarding treatment regimens and outcomes.
Redox changes during cold acclimation affect freezing tolerance but not the vegetative/reproductive transition of the shoot apex in wheat
Authors: Soltész A. , Tímár I. , Vashegyi I. , Tóth B. , Kellős T. , Szalai G. , Vágújfalvi A. , Kocsy G. , Galiba G. 
Published: January 2011

AbstractCold acclimation is necessary for winter wheat (Triticum aestivum L.) to achieve its genetically determined maximum freezing tolerance, and cold also fulfils the vernalisation requirement. Chromosome 5A is a major regulator of these traits. The aim of the present study was to discover whether changes in the half‐cell redox potential of the glutathione/glutathione disulphide (GSH/GSSG) and ascorbate/dehydroascorbate (AA/DHA) couples induced by cold acclimation are related to freezing tolerance and vernalisation requirement in a specific genetic system including chromosome 5A substitution lines. The amounts of H2O2 and AA, and the AA/DHA ratio showed a rapid and transient increase in the crown of all genotypes during the first week of acclimation, followed by a gradual increase during the subsequent 2 weeks. The amount of GSH and its ratio compared to GSSG quickly decreased during the first day, while later these parameters showed a continuous slow increase. The H2O2, AA and GSH concentrations, AA/DHA and GSH/GSSG ratios and the half‐cell reduction potential of the GSH/GSSG couple were correlated with the level of freezing tolerance after 22 days at 2 °C; hence these parameters may have an important role in the acclimation process. In contrast to H2O2 and the non‐enzymatic antioxidants, the lipid peroxide concentration and activity of the four antioxidant enzymes exhibited a transient increase during the first week, with no significant difference between genotypes. None of the parameters studied showed any relationship with the vegetative/generative transition state monitored as apex morphology and vernalisation gene expression.
Zoobenthos as an environmental quality element: the ecological significance of sampling design and functional traits
Authors: Aarnio Katri , Mattila Johanna , Törnroos Anna , Bonsdorff Erik 
Published: January 2011

AbstractThe EC Water Frame Directive (WFD) states that all coastal water bodies must achieve ‘good ecological status’ by the year 2015. A range of different classification methods have been developed and used to define ecological status to support the WFD. The aim of this study was to compare the effects of using two different mesh sizes of sieve (1.0 and 0.5 mm) on zoobenthic assemblages and on the ecological status of benthic macrofauna (using the Brackish water benthic index, BBI) in three ecologically distinct archipelago areas (Inner, Middle and Outer) in the Åland Islands, Northern Baltic Sea. We performed a biological trait analysis (BTA) to evaluate differences in the functional (trait) diversity of macrofauna collected using different mesh sizes and estimate the ecological relevance of mesh size. The results showed that sieve mesh size had significant effects on the recorded number of species, abundance, and total biomass of the zoobenthos. Small‐bodied species and juveniles (e.g. Macoma balthica) were not observed when using a 1.0‐mm mesh. The ecological status (sensu WFD) was only slightly affected by the mesh size, and all areas had good or high ecological status. BTA showed a difference in trait composition when using 0.5‐ or 1.0‐mm mesh, particularly in the Outer area, where the proportion of small‐sized species was high. Our results highlight how biological traits, in addition to species number and biomass, can play a key role when analyzing ecosystem structure for assessment and classification of coastal ecosystems. We show that combining traditional monitoring for the EU WFD with a functional analysis strengthens our ability to interpret environmental quality, and thus increases the precision of our advice for management purposes.
Hydrurus foetidus (Chromista, Chrysophyceae): A large freshwater chromophyte alga in laboratory culture
Authors: Klaveness Dag , Lindstrøm Eli‐Anne 
Published: January 2011

SUMMARYThe psychrophilic freshwater alga Hydrurus foetidus (Villars) Trevisan has previously resisted laboratory culturing in liquid media. We investigated the use of microbiological techniques adapted to specific requirement for low temperature and high turbulence of the alga. We found that successful culturing required cleaning steps, where pieces of the alga were dissected out and plated on agar under cold conditions. From here, unialgal colonies could be isolated and inoculated into liquid media under appropriate conditions. Turbulence, created by a laboratory shaker, is critical. Sufficient light (30–100 µmol m–2 s–1) and low temperature (here 2–3°C) are necessary. This rather common but highly under‐investigated freshwater alga has potential for basic and applied research when available as laboratory cultures.