bluuebunny/crossref_metadata_2025 huggingface dataset:
Desenvolvimento neuropsicomotor: o teste de Denver na triagem dos atrasos cognitivos e neuromotores de pré-escolares
Authors: Brito Cileide Mascarenhas Lopes , Vieira Graciete Oliveira , Costa Maria da Conceição Oliveira , Oliveira Nelson Fernandes de
Published: August 2011

O objetivo deste estudo foi verificar a prevalência e fatores associados no que se refere ao desempenho anormal do desenvolvimento neuropsicomotor de crianças matriculadas na educação infantil pública em Feira de Santana, Bahia, Brasil, em 2009 (n = 438). Esta é uma pesquisa epidemiológica de corte transversal, com amostragem por conglomerado e sorteio das escolas e crianças. Foram verificados os fatores associados por meio de aplicação de questionário às mães e de teste Denver II ao filho. A análise estatística realizou o teste χ2 com intervalo de 95% de confiança e α = 5%. A prevalência de desempenho anormal do desenvolvimento foi 46,3%. Na análise de regressão logística, as variáveis estatisticamente significantes associadas foram: sexo masculino (RP = 1,43; p = 0,00), cinco anos de idade (RP = 1,42; p = 0,00), não realização de pré-natal (RP = 1,41; p = 0,00), início do pré-natal > 3 meses (RP = 1,25; p = 0,00) e consumo alcoólico na gestação (RP = 1,55; p = 0,00). A prevalência foi elevada, apontando a necessidade de pré-natal precoce, alertando sobre o consumo alcoólico, e de vigilância nos primeiros anos de vida, visando a prevenir ou tratar precocemente as alterações.
Rastreamento oportunístico do câncer de mama entre mulheres jovens no Estado do Maranhão, Brasil
Authors: Lima Ana Lívia Pontes de , Rolim Nívya Carla de Oliveira Pereira , Gama Mônica Elinor Alves , Pestana Aline Lima , Silva Elza Lima da , Cunha Carlos Leonardo Figueiredo
Published: August 2011

Apesar de infrequente, o câncer de mama em mulheres com menos de 40 anos merece destaque, pois o diagnóstico exige alto índice de suspeição clínica; assim, as práticas preventivas devem ser valorizadas entre mulheres em idade fértil com o rastreamento oportunístico configurando-se em estratégia relevante na abordagem às mulheres. Objetivou-se estudar as práticas adotadas por mulheres jovens para prevenção do câncer de mama no Maranhão, Brasil. Trata-se de estudo de base populacional, descritivo, realizado de junho/2007 a janeiro/2008. A maioria das maranhenses tem baixa renda (42,1%) e menos de oito anos de escolaridade (62,6%). Cerca de 30% relataram o autoexame da mama; entre as mulheres acima de 35 anos, 71,6% nunca realizaram mamografia. Prevaleceu o exame clínico (35,2%) dentre as medidas preventivas, observando-se incremento de 11,5% nessa prática nos últimos dez anos. Tais informações acerca do rastreamento oportunístico do câncer de mama no Maranhão irão auxiliar na formulação das políticas públicas de saúde específicas para o estado.
Soil aquifer treatment using advanced primary effluent
Authors: Sharma Saroj K. , Hussen Mustefa , Amy Gary
Published: August 2011

Soil aquifer treatment (SAT) using primary effluent (PE) is an attractive option for wastewater treatment and reuse in many developing countries with no or minimal wastewater treatment. One of the main limitations of SAT of PE is rapid clogging of the infiltration basin due to high suspended solid concentrations. Some pre-treatment of PE before infiltration is likely to reduce this limitation, improve performance of SAT and help to implement this technology effectively. The effects of three pre-treatment options namely sedimentation (SED), coagulation (COAG) and horizontal roughing filtration (HRF) on SAT were analyzed by conducting laboratory-scale batch and soil column experiments. The sedimentation and coagulation pre-treatments led to less head loss development and reduction of clogging effect. The head loss development in soil column using PE + COAG and PE + SED was reduced by 85 and 72%, respectively, compared to PE alone without any pre-treatment. The overall dissolved organic carbon (DOC) removal of pre-treatments and soil column collectively were 34, 44, 51 and 43.5% for PE without any pre-treatment, PE + SED, PE + COAG and PE + HRF, respectively. Coagulation pre-treatment of PE was found to be the most effective option in terms of suspended solids, DOC and nitrogen removal. Sedimentation pre-treatment of PE could be attractive where land is relatively less expensive for the construction of sedimentation basins.
Chemical disinfection of Legionella in hot water systems biofilm: a pilot-scale 1 study
Authors: Farhat Maha , Trouilhé Marie-Cécile , Forêt Christophe , Hater Wolfgang , Moletta-Denat Marina , Robine Enric , Frère Jacques
Published: August 2011

Legionella bacteria encounter optimum growing conditions in hot water systems and cooling towers. A pilot-scale 1 unit was built in order to study the biofilm disinfection. It consisted of two identical loops, one used as a control and the other as a ‘Test Loop’. A combination of a bio-detergent and a biocide (hydrogen peroxide + peracetic acid) was applied in the Test Loop three times under the same conditions at 100 and 1,000 mg/L with a contact time of 24 and 3–6 hours, respectively. Each treatment test was preceded by a three week period of biofilm re-colonization. Initial concentrations of culturable Legionella into biofilm were close to 103 CFU/cm2. Results showed that culturable Legionella spp. in biofilm were no longer detectable three days following each treatment. Nevertheless, initial Legionella spp. concentrations were recovered 7 days after the treatments (in two cases). Before the tests, Legionella spp. and L. pneumophila PCR counts were both about 104 GU/cm2 in biofilm and they both decreased by 1 to 2 log units 72 hours after each treatment. The three tests had a good but transient efficiency on Legionella disinfection in biofilm.
Impact of operating history on mixed culture fermentation microbial ecology and product mixture
Authors: Lu Y. , Slater F. R. , Mohd-Zaki Z. , Pratt S. , Batstone D. J.
Published: August 2011

Mixed culture fermentation is an alternative to pure culture fermentation for production of biofuels and valuable products. A glucose-fed, continuous reactor was operated cyclically to a central pH of 5.5 from a number of precedent pHs, from 4.5 to 7.5. At each pH, stable chemical production was reached after 2 retention times and was held for least 2 further retention times prior to the next change. Bacterial groups were identified by phylogenetic analysis of 16S rRNA gene clones. Bacterial community dynamics were monitored by terminal-restriction fragment length polymorphism. More ethanol was produced at high pH, and more butyrate at lower pH. At pH 5.5, the product spectrum was not measurably influenced by precedent pH but showed seemingly random changes. The impact of precedent pH on community structure was more systematic, with clear indications that when the pH was returned to 5.5, the bacterial group that was dominant at the precedent pH remained at high abundance. This result is important, since it indicates a decoupling between microbial function (as indicated by product spectrum), and community structure. More work is needed to determine the longevity of this hysteresis effect. There was evidence that groups retained their ability to re-emerge even after times of low abundance.
‘Recovery’, a New Western Wheatgrass Cultivar with Improved Seedling Establishment on Rangelands
Authors: Waldron Blair L. , Jensen Kevin B. , Palazzo Antonio J. , Cary Timothy J. , Robins Joseph G. , Peel Michael D. , Ogle Daniel G. , John Loren St.
Published: August 2011

‘Recovery’ western wheatgrass [Pascopyrum smithii (Rydb.) Barkworth & D. R. Dewy] (Reg. No. CV‐32, PI 660509) was released in December 2009 by the USDA‐ARS, the Engineer Research and Development Center of the U.S. Army Corps of Engineers, and the USDA‐NRCS. Recovery was developed for reseeding rangelands following severe disturbance, frequent fires, and soil erosion, and it was selected with emphasis on improved and faster seedling establishment. Recovery was evaluated as TC3, TC‐Rich, Army WWG, SERDP WWG, and NRCS‐9076517 and was developed as a synthetic cultivar using two cycles of recurrent selection for plant vigor, seed yield, and rate of seedling emergence from a deep planting depth. In field evaluations, Recovery had an increased frequency of seedlings during the establishment year, when averaged across eight locations, than ‘Arriba’, ‘Barton’, ‘Flintlock’, ‘Rodan’, and ‘Rosana’ western wheatgrasses. Recovery continued to have superior stand until 4–6 yr after planting, when due to their rhizomatous nature, all the western wheatgrasses had similar stand frequencies. Recovery western wheatgrass provides land managers with a new western wheatgrass cultivar possessing rapid establishment for use in areas that are frequently disturbed, such as military training lands. The use of Recovery will help reduce soil erosion and weed invasion following such disturbances.
Registration of ‘York’ Peanut
Authors: Gorbet Daniel W. , Tillman Barry L.
Published: August 2011

‘York’ (Reg. No. CV‐114, PI 653717) peanut (Arachis hypogaea L. subsp. hypogaea var. hypogaea) cultivar was developed at the University of Florida, Florida Agricultural Experiment Station, North Florida Research and Education Center near Marianna, FL, and was approved for release in 2006. York was tested as UF04321 and has runner market‐type pods and seed with a prostrate runner growth habit. Under irrigated production in Florida, York matures in approximately 150 d, making it a late‐maturing cultivar. York has good‐to‐excellent multiple disease resistance, namely to late leaf spot [caused by Cercosporidium personatum (Berk. & M.A. Curtis) Deighton], Tomato spotted wilt virus, and white mold/stem rot (caused by Sclerotium rolfsii Sacc.). York has shown good‐to‐excellent pod yields and disease resistance in Florida tests. Seed of York have a high‐oleic oil chemistry (approximately 80% oleic fatty acid), which greatly enhances shelf life and quality characteristics. York should provide southeastern U.S. growers with a cultivar having excellent disease resistance and quality characteristics.
Low genetic diversity, moderate local adaptation, and phylogeographic insights in Cornus nuttallii (Cornaceae)
Authors: Keir Karolyn R. , Bemmels Jordan B. , Aitken Sally N.
Published: August 2011

•Premise of the study: Genetic knowledge is completely lacking for Pacific dogwood (Cornus nuttallii), a western North American temperate tree that is pollinated and dispersed by biological vectors. We investigated how history, geography, and climate have affected population genetic structure, local adaptation, and the phylogeography of this species.

•Methods: We examined patterns and levels of diversity in nuclear microsatellites (SSRs) and cpDNA haplotypes in populations from across the species range. We compared these results to population differentiation and genetic clines in phenotypic traits in a common garden.

•Key results: Genetic diversity was low for both nuclear SSRs and cpDNA. There was a lack of population structure (FST = 0.090) in the coastal portion of the species range, with estimates of population genetic diversity in microsatellite markers decreasing with latitude from California to British Columbia. A disjunct interior population in Idaho 450 km from the coastal range had the lowest diversity but the highest divergence of all populations studied. Only a single nucleotide polymorphism was discovered after sequencing 5547 base pairs in seven noncoding regions of cpDNA. Both cpDNA haplotypes were widely distributed throughout the species range. Quantitative variation among populations was moderate (0.11 ≤ QST ≤ 0.63), and weak but significant adaptive clines were found between quantitative traits and population climatic variables (0.09 ≤ R2 ≤ 0.34).

•Conclusions: Cornus nuttallii likely faced a population bottleneck in a single southern refugium during the Last Glacial Maximum. Despite low genetic diversity, it is weakly to moderately locally adapted.
Frequent pseudogenization and loss of the plastid‐encoded sulfate‐transport genecysA throughout the evolution of liverworts
Authors: Wickett Norman J. , Forrest Laura L. , Budke Jessica M. , Shaw Blanka , Goffinet Bernard
Published: August 2011

•Premise of the study:The presence or absence of a functional copy of a plastid gene may reflect relaxed selection, and may be phylogenetically significant, reflecting shared ancestry. In some liverworts, the plastid genecysA is a pseudogene (inferred to be nonfunctional). We surveyed 63 liverworts from all major clades to determine whether the loss ofcysA is phylogenetically significant, whether intact copies ofcysA are under selective constraints, and whether rates of nucleotide substitution differ in other plastid genes from taxa with and without a functional copy ofcysA.

•Methods:Primers annealing to flanking and internal regions were used to amplify and sequencecysA from 61 liverworts. Two additionalcysA sequences were downloaded from NCBI. The ancestral states ofcysA were reconstructed on a phylogenetic hypothesis inferred from seven markers. Rates of nucleotide substitution were estimated for three plastid loci to reflect the intrinsic mutation rate in the plastid genome. The ratio of nonsynonymous to synonymous substitutions was estimated for intact copies ofcysA to infer selective constraints.

•Key results:Throughout liverworts,cysA has been lost up to 29 times, yet intact copies ofcysA are evolving under selective constraints. Gene loss is more frequent in groups with an increased substitution rate in the plastid genome.

•Conclusions:The number of inferred losses ofcysA in liverworts exceeds any other reported plastid gene. Despite frequent losses,cysA is evolving under purifying selection in liverworts that retain the gene. It appears thatcysA is lost more frequently in lineages characterized by a higher rate of nucleotide substitutions in the plastid.
Amputation of Finger by Horse Bite With Complete Avulsion of Both Flexor Tendons
Authors: Koren Lior , Stahl Shalom , Rovitsky Alexey , Peled Eli
Published: August 2011

Amputation of fingers with tendon avulsion occurs through a traction injury, and most occur through a ring avulsion mechanism. Usually the flexor digitorum profundus is torn out with the amputated finger. Replantation usually is recommended only when the amputation is distal to the flexor digitorum superficialis insertion. Animal bites are relatively common, with a decreasing order of frequency of dogs, cats, and humans. Horse bites are relatively infrequent but are associated with crush injuries and tissue loss when they occur.

This article describes a 23-year-old man with amputation of his middle finger at the level of the proximal phalanx after being bitten by a horse. The amputated stump was avulsed with the middle finger flexor digitorum profundus and flexor digitorum superficialis torn from the muscle-tendon junction from approximately the middle of the forearm. The patient had no other injuries, and he was able to move his other 4 fingers with only mild pain. As the amputated digit was not suitable for replantation, the wound was irrigated and debrided. The edges of the phalanx were trimmed, and the edges of the wound were sutured. Tetanus toxoid and rabies vaccine were administered, along with intravenous amoxicillin and clavulanic acid. The patient was discharged from the hospital 2 days later, with no sign of infection of the wound or compartment syndrome of the forearm. This case demonstrates the weakest point in the myotendinous junction and emphasizes the importance of a careful physical examination in patients with a traumatic amputation.
Decreased Parasite Load and Improved Cognitive Outcomes Caused by Deworming and Consumption of Multi-Micronutrient Fortified Biscuits in Rural Vietnamese Schoolchildren
Authors: Nga Tran T. , Winichagoon Pattanee , Dijkhuizen Marjoleine A. , Khan Nguyen C. , Wasantwisut Emorn , Wieringa Frank T.
Published: August 2011

Micronutrient deficiencies are associated with impaired growth and cognitive function. A school-based fortification program might benefit schoolchildren but a high prevalence of parasite infestation might affect effectiveness. A randomized, double-blind, placebo-controlled 2 × 2 factorial trial was conducted to assess the efficacy of multi-micronutrient fortified biscuits with or without de-worming on growth, cognitive function, and parasite load in Vietnamese schoolchildren. Schoolchildren (n = 510), 6–8 years of age were randomly allocated to receive albendazole or placebo at baseline and four months of multi-micronutrient fortified biscuits (FB) or non-fortified biscuits. Children receiving FB for four months scored higher on two cognitive tests: Raven's Colored Progressive Matrices and the Digit Span Forward test. Children receiving albendazole plus FB had the lowest parasite load after four months. In children receiving FB, mid-upper arm circumference was slightly improved (+0.082 cm) but there were no differences in other indexes of anthropometry. Combining multi-micronutrient fortified biscuits with de-worming is an effective strategy.
The Impact of Private Long-Term Care Insurance on the Use of Long-Term Care
Authors: Li Yong , Jensen Gail A.
Published: August 2011

This paper investigates the effects of privately purchased long-term care insurance (LTCI) on three major types of long-term care services: nursing home care, paid home care, and informal care received from family and friends. Using 2002–2008 data from the ongoing Health and Retirement Study, we analyze the determinants of long-term care utilization simultaneously with the determinants of holding LTCI. We find that LTCI has modest effects on the likelihood of using long-term care services. For the very frail elderly, private LTCI enhances their access to nursing home care. For those with moderate disability, LTCI makes it more likely that they can remain at home and receive home care services, instead of going to a nursing home. We find no evidence that formal care substitutes for informal care in the presence of LTCI. These findings suggest that if LTCI becomes much more prevalent in the future, many older adults will be able to choose the type of long-term care arrangement that best suits their needs.
Simulating the oxygen content of ambient organic aerosol with the 2D volatility basis set
Authors: Murphy B. N. , Donahue N. M. , Fountoukis C. , Pandis S. N.
Published: August 2011

Abstract. A module predicting the oxidation state of organic aerosol (OA) has been developed using the two-dimensional volatility basis set (2D-VBS) framework. This model is an extension of the 1D-VBS framework and tracks saturation concentration and oxygen content of organic species during their atmospheric lifetime. The host model, a one-dimensional Lagrangian transport model, is used to simulate air parcels arriving at Finokalia, Greece during the Finokalia Aerosol Measurement Experiment in May 2008 (FAME-08). Extensive observations were collected during this campaign using an aerosol mass spectrometer (AMS) and a thermodenuder to determine the chemical composition and volatility, respectively, of the ambient OA. Although there are several uncertain model parameters, the consistently high oxygen content of OA measured during FAME-08 (O:C = 0.8) can help constrain these parameters and elucidate OA formation and aging processes that are necessary for achieving the high degree of oxygenation observed. The base-case model reproduces observed OA mass concentrations (measured mean = 3.1 μg m−3, predicted mean = 3.3 μg m−3) and O:C (predicted O:C = 0.78) accurately. A suite of sensitivity studies explore uncertainties due to (1) the anthropogenic secondary OA (SOA) aging rate constant, (2) assumed enthalpies of vaporization, (3) the volatility change and number of oxygen atoms added for each generation of aging, (4) heterogeneous chemistry, (5) the oxidation state of the first generation of compounds formed from SOA precursor oxidation, and (6) biogenic SOA aging. Perturbations in most of these parameters do impact the ability of the model to predict O:C well throughout the simulation period. By comparing measurements of the O:C from FAME-08, several sensitivity cases including a high oxygenation case, a low oxygenation case, and biogenic SOA aging case are found to unreasonably depict OA aging, keeping in mind that this study does not consider possibly important processes like fragmentation that may offset mass gains and affect the prediction bias. On the other hand, many of the cases chosen for this study predict average O:C estimates that are consistent with the observations, illustrating the need for more thorough experimental characterizations of OA parameters including the enthalpy of vaporization and oxidation state of the first generation of SOA products. The ability of the model to predict OA concentrations is less sensitive to perturbations in the model parameters than its ability to predict O:C. In this sense, quantifying O:C with a predictive model and constraining it with AMS measurements can reduce uncertainty in our understanding of OA formation and aging.
TiO2 Nanocrystals Synthesized by Laser Pyrolysis for the Up‐Scaling of Efficient Solid‐State Dye‐Sensitized Solar Cells
Authors: Melhem Hussein , Simon Pardis , Beouch Layla , Goubard Fabrice , Boucharef Mourad , Di Bin Catherine , Leconte Yann , Ratier Bernard , Herlin‐Boime Nathalie , Bouclé Johann
Published: August 2011

A crucial issue regarding emerging nanotechnologies remains the up‐scaling of new functional nanostructured materials towards their implementation in high performance applications on a large scale. In this context, we demonstrate high efficiency solid‐state dye‐sensitized solar cells prepared from new porous TiO2 photoanodes based on laser pyrolysis nanocrystals. This strategy exploits a reduced number of processing steps as well as non‐toxic chemical compounds to demonstrate highly porous TiO2 films. The possibility to easily tune the TiO2 nanocrystal physical properties allows us to demonstrate all solid‐state dye‐sensitized devices based on a commercial benchmark materials (organic indoline dye and molecular hole transporter) presenting state‐of‐the‐art performance comparable with reference devices based on a commercial TiO2 paste. In particular, a drastic improvement in pore infiltration, which is found to balance a relatively lower surface area compared to the reference electrode, is evidenced using laser‐synthesized nanocrystals resulting in an improved short‐circuit current density under full sunlight. Transient photovoltage decay measurements suggest that charge recombination kinetics still limit device performance. However, the proposed strategy emphasizes the potentialities of the laser pyrolysis technique for up‐scaling nanoporous TiO2 electrodes for various applications, especially for solar energy conversion.
Relational Aggression in Women during Emerging Adulthood: A Social Process Model
Authors: Ostrov Jamie M. , Hart Emily J. , Kamper Kimberly E. , Godleski Stephanie A.
Published: August 2011

Two studies investigated potential mediators of the association between relational victimization and relational aggression. Self‐report measures of aggressive behavior among peers, exclusivity, hostile attribution biases, and borderline personality disorder (BPD) symptoms were collected. In study 1, participants were 180 female emerging adults (M = 18.82, SD = 1.18). Both exclusivity and hostile attribution biases for relational provocations were found to partially mediate the association between relational victimization and relational aggression. In study 2, participants were 54 female emerging adults (M = 19.16, SD = 1.11). Symptoms of BPD were not found to mediate the association between relational victimization and relational aggression, yet unique associations with relational aggression were observed. The results add to recent research guided by a social process model in which links between victimization and aggression are more clearly understood. Copyright © 2011 John Wiley & Sons, Ltd.
Impact of gene vector design on the control of recombinant monoclonal antibody production by chinese hamster ovary cells
Authors: Davies Sarah L. , O'Callaghan Peter M. , McLeod Jane , Pybus Leon P. , Sung Yun Hee , Rance James , Wilkinson Stephen J. , Racher Andrew J. , Young Robert J. , James David C.
Published: August 2011

In this study, we systematically compare two vector design strategies for recombinant monoclonal antibody (Mab) synthesis by Chinese hamster ovary (CHO) cells; a dual open reading frame (ORF) expression vector utilizing separate cytomegalovirus (CMV) promoters to drive heavy chain (HC) and light chain (LC) expression independently, and a single ORF vector design employing a single CMV promoter to drive HC and LC polypeptide expression joined by a foot and mouth disease virus F2A polypeptide self‐cleaving linker sequence. Initial analysis of stable transfectants showed that transfectants utilizing the single ORF vector designs exhibited significantly reduced Mab production. We employed an empirical modeling strategy to quantitatively describe the cellular constraints on recombinant Mab synthesis in all stable transfectants. In all transfectants, an intracellular molar excess of LC polypeptide over HC polypeptide was observed. For CHO cells transfected with the single ORF vectors, model‐predicted, and empirical intracellular intermediate levels could only be reconciled by inclusion of nascent HC polypeptide degradation. Whilst a local sensitivity analysis showed that qMab of all transfectants was primarily constrained by recombinant mRNA translation rate, our data indicated that all single ORF transfectants exhibited a reduced level of recombinant gene transcription and that Mab folding and assembly reactions generically exerted greater control over qMab. We infer that the productivity of single ORF transfectants is limited by ER processing/degradation “capacity” which sets a limit on transcriptional input. We conclude that gene vector design for oligomeric recombinant proteins should be based on an understanding of protein‐specific synthetic kinetics rather than polypeptide stoichiometry. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011
Separated and Trafficked Children: The Challenges for Child Protection Professionals
Authors: Rigby Paul
Published: August 2011

Unaccompanied asylum‐seeking children are one of the most vulnerable groups of children and those who have been trafficked present with additional needs, posing new challenges for child protection professionals. Drawing on a research programme commissioned to inform policy and practice in Glasgow, this paper identifies issues emerging for practitioners working with separated children who have been trafficked. The commitment of frontline staff and increased multiagency working appear to be positive aspects of the work. Initial identification and assessment present a major challenge for reasons including cultural issues, the trauma and fear of children affecting engagement and the potential for ongoing contact with traffickers to compromise safeguarding. Trafficking is a particularly complex area of child protection work, made more problematic by the international dimensions to the trade and the absence of a clear definition and conceptual framework that can fully inform interventions and practice. Copyright © 2011 John Wiley & Sons, Ltd.

‘Initial identification and assessment present a major challenge’
Robust exponential l2 − l ∞  control for discrete‐time switched system: A cone complement linearization method
Authors: Hou Linlin , Zong Guangdeng , Wu Yuqiang
Published: August 2011

The robust exponential l2 − l ∞  control problem is considered in this paper for discrete‐time switched systems with both time‐varying delay and norm‐bounded parameter uncertainties. An exponential l2 − l ∞  performance index is first introduced for the discrete‐time switched systems. The designed controller is a memory exponential l2 − l ∞  controller. By introducing an average dwell time approach and a Lyapunov–Krasovskii functional technique, some sufficient criteria guaranteeing exponential stability are presented, and the desired memory exponential l2 − l ∞  controller is established by resorting to a cone complement linearization method. Some results on exponential stability using memoryless exponential l2 − l ∞  controller and asymptotical stability with traditional l2 − l ∞  performance index are also established. Finally, a numerical example is provided to demonstrate that the proposed approach can lead to less conservatism compared with the developed result using memoryless exponential l2 − l ∞  controller and asymptotical stability analysis with traditional l2 − l ∞  performance index. Copyright © 2011 John Wiley & Sons, Ltd.
Nanostructure and properties of proton‐conducting sulfonated poly(ether ether ketone) (SPEEK) and zirconia–SPEEK hybrid membranes for direct alcohol fuel cells: effect of the nature of swelling solvent and incorporation of heteropolyacid
Authors: Kawaguti Carla Akimi , Dahmouche Karim , Gomes Ailton de Souza
Published: August 2011

The influence, on membrane nanostructure and properties, of water or ethanol as swelling solvent of sulfonated poly(ether ether ketone) (SPEEK) and zirconia–SPEEK hybrid membranes prepared using the sol–gel process has been investigated. Independent of the solvent, small‐angle X‐ray scattering measurements reveal the existence of a two‐level hierarchical structure in SPEEK of greater sulfonation level, consisting of solvent‐swelled spatially correlated primary SO3H‐rich ionic clusters of around 15 Å in size, forming larger secondary aggregates well dispersed in the PEEK matrix. The size of the primary nanodomains and the connectivity between domains are determining parameters for protonic conductivity, solvent swelling ability and permeability of the membranes. For both SPEEK and zirconia–SPEEK membranes containing ethanol, the pronounced affinity of ethanol molecules with SPEEK leads to an increase in the size of ionic clusters and of the number of connecting channels between clusters compared to membranes containing water. This promotes solvent swelling and proton conductivity. The increase in permeability to water induced by incorporation of ethanol in place of water in both polymeric and hybrid membranes is less in the hybrid membranes. This result suggests that the potential use of zirconia–SPEEK hybrid membranes in direct alcohol fuel cells is more promising than that of pure SPEEK, due not only to the less probable alcohol and water penetration in the membranes associated with their lower permeability, but also to the fact that an eventual penetration of alcohol in hybrid membranes should reduce the risk of cathode flooding compared to zirconia‐free SPEEK membranes. Copyright © 2011 Society of Chemical Industry
Use of legume green manures as nitrogen sources for corn production
Authors: Liebman Matt , Graef Rhonda L. , Nettleton Daniel , Cambardella Cynthia A.
Published: August 2011

Recent volatility in supplies and prices of natural gas and synthetic nitrogen (N) fertilizer suggests a need to develop and refine alternative strategies for supplying N to corn. In this study, conducted in north-eastern Iowa, we examined the use of red clover and alfalfa green manures as means of supplying N to a succeeding corn crop. Red clover intercropped with oat produced significantly more biomass and contained more N than alfalfa intercropped with oat. Tilling green manures in the fall or delaying tillage until the following spring did not have a consistent effect on green manure N content. Without N fertilizer, corn grain yield following oat–red clover and oat–alfalfa was 25–63% greater than following oat grown alone, but at the highest fertilizer rate (202 kg N ha−1), there was no difference in corn yield between oat–legume and oat-alone treatments. These patterns support the premise that legume green manure effects on corn yield were N-related. Red clover green manure had an N fertilizer replacement value for corn of 87–184 kg N ha−1; alfalfa supplied corn with the equivalent of 70–121 kg N ha−1. At a fossil energy cost for N fertilizer of 57 MJ kg−1N, reducing synthetic N fertilizer applications to corn by 70–184 kg N ha−1would represent a fossil fuel savings of 3990–10,488 MJ ha−1, equivalent to the energy content of 104–274 m3of natural gas. These types of savings are likely to become increasingly important as fossil energy supplies become scarcer and fertilizer prices rise.
Body Fat, Abdominal Fat, and Body Fat Distribution Is Related to Left Atrial Diameter in Young Children
Authors: Dencker Magnus , Thorsson Ola , Karlsson Magnus K. , Lindén Christian , Andersen Lars B. , Wollmer Per
Published: August 2011

In adults, the size of the left atria (LA) has important prognostic information. In obese adults, adolescents and children enlargement of LA have been observed. This has not been investigated on a population‐based level in young children. We therefore assessed if total body fat mass (TBF), abdominal fat, and body fat distribution were related to LA diameter. Cross‐sectional study of 244 children (boys = 137 and girls n = 107) aged 8–11 years, recruited from an urban population‐based cohort. Dual‐energy X‐ray absorptiometry (DXA) measured total lean body mass, TBF, and abdominal fat mass (AFM). Body fat was also calculated as a percentage of body mass (BF%). Body fat distribution (AFM/TBF) was calculated. Echocardiography was performed with two‐dimensional guided M‐mode. LA diameter was measured and left ventricular mass (LVM) was calculated. Systolic blood pressure and diastolic blood pressure were measured and maturity assessed according to Tanner. There were significant (P < 0.05) univariate correlations for all children between TBF (r = 0.40), BF% (r = 0.32), AFM (r = 0.41), and AFM/TBF (r = 0.41) vs. LA diameter. Multiple regression analyses with the inclusion of possible confounders such as lean body mass, blood pressure, gender, age, and Tanner stage revealed that TBF, AFM, and AFM/TBF were all independently related to LA diameter. Differences in the different body fat measurements explained 6–9% of the variance in LA size. These results demonstrated that both total body fat, AFM, and body fat distribution are already at a young age negatively and independently associated to LA diameter.
Spin-dependent transport in II-VI magnetic semiconductor resonant tunneling diode
Authors: Mnasri S. , Nasrallah S. Abdi-Ben , Bouazra A. , Sfina N. , Said M.
Published: August 2011

Spin-dependent transport through the CdTe/CdMgTe/CdMnTe/CdMgTe/CdTe heterostructure is investigated theoretically. Using the transfer matrix method and the effective-mass approximation, the effect of resonant states on spin transport is studied in a magnetic semiconductor resonant tunneling diode. The magnetic field dependences of the transmission coefficients, current densities, and tunnel magnetoresistance for the considered system have been studied. The doping and temperature effects on the current are also investigated theoretically. The numerical results show that the CdMnTe layers, which act as spin filters, polarize the electric currents. This spin splitting of the energy levels enables one to select the resonant condition for the desired spin by adjusting the magnetic field or the applied bias. The spin-up component of the current-density shows a strong suppression for increasing magnetic fields; the total current density is dominated by the spin-down component. It is also found that the tunnel magnetoresistance depends strongly on the magnetic field and the applied voltage.
Dual-trap optical tweezers with real-time force clamp control
Authors: Wallin Anders E. , Ojala Heikki , Ziedaite Gabija , Hæggström Edward
Published: August 2011

Single molecule force clamp experiments are widely used to investigate how enzymes, molecular motors, and other molecular mechanisms work. We developed a dual-trap optical tweezers instrument with real-time (200 kHz update rate) force clamp control that can exert 0–100 pN forces on trapped beads. A model for force clamp experiments in the dumbbell-geometry is presented. We observe good agreement between predicted and observed power spectra of bead position and force fluctuations. The model can be used to predict and optimize the dynamics of real-time force clamp optical tweezers instruments. The results from a proof-of-principle experiment in which lambda exonuclease converts a double-stranded DNA tether, held at constant tension, into its single-stranded form, show that the developed instrument is suitable for experiments in single molecule biology.
Electronic spectroscopy of the previously unknown arsenic carbide (AsC) free radical
Authors: Yang Jie , Clouthier Dennis J.
Published: August 2011

The previously unknown arsenic carbide (AsC) free radical has been identified in the gas phase through a combination of laser-induced fluorescence (LIF), single vibronic level emission, and stimulated emission pumping (SEP) spectroscopy in a supersonic expansion. The As12C and As13C isotopologues have been detected as products of an electric discharge in mixtures of arsine (AsH3) and carbon dioxide (12CO2 or 13CO2) in high pressure argon. The B 2Σ+-X 2Σ+ band system was recorded by LIF spectroscopy and emission transitions from the B state down to the ground state and to the low-lying A 2Πi state were observed. High resolution studies of the B−X 0–0 band by LIF and the B−A 0–0 band by SEP spectroscopy enabled a determination of the molecular structures in the three states. Although CN, CP, and AsC have similar X 2Σ+ and A 2Πi. states, the B 2Σ+ state molecular orbital configuration of CP and AsC differs from that of the CN free radical.
Silicon structuring by etching with liquid chlorine and fluorine precursors using femtosecond laser pulses
Authors: Radu C. , Simion S. , Zamfirescu M. , Ulmeanu M. , Enculescu M. , Radoiu M.
Published: August 2011

The aim of this study is to investigate the micrometer and submicrometer scale structuring of silicon by liquid chlorine and fluorine precursors with 200 fs laser pulses working at both fundamental (775 nm) and frequency doubled (387 nm) wavelengths. The silicon surface was irradiated at normal incidence by immersing the Si (111) substrates in a glass container filled with liquid chlorine (CCl4) and fluorine (C2Cl3F3) precursors. We report that silicon surfaces develop an array of spikes with single step irradiation processes at 775 nm and equally at 387 nm. When irradiating the Si surface with 400 pulses at 330 mJ/cm2 laser fluence and a 775 nm wavelength, the average height of the formed Si spikes in the case of fluorine precursors is 4.2 μm, with a full width at half maximum of 890 nm. At the same irradiation wavelength chlorine precursors develop Si spikes 4 μm in height and with a full width at half maximum of 2.3 μm with irradiation of 700 pulses at 560 mJ/cm2 laser fluence. Well ordered areas of submicrometer spikes with an average height of about 500 nm and a width of 300 nm have been created by irradiation at 387 nm by chlorine precursors, whereas the fluorine precursors fabricate spikes with an average height of 700 nm and a width of about 200 nm. Atomic force microscopy and scanning electron microscopy of the surface show that the formation of the micrometer and sub-micrometer spikes involves a combination of capillary waves on the molten silicon surface and laser-induced etching of silicon, at both 775 nm and 387 nm wavelength irradiation. The energy-dispersive x-ray measurements indicate the presence of chlorine and fluorine precursors on the structured surface. The fluorine precursors create a more ordered area of Si spikes at both micrometer and sub-micrometer scales. The potential use of patterned Si substrates with gradient topography as model scaffolds for the systematic exploration of the role of 3D micro/nano morphology on cell adhesion and growth is envisaged.
Anisotropic bonded magnets fabricated via surfactant-assisted ball milling and magnetic-field processing
Authors: Poudyal Narayan , Nguyen Van Vuong , Rong Chuan-bing , Liu J Ping
Published: August 2011

Anisotropic bonded magnets are fabricated by surfactant-assisted ball milling in a magnetic field and magnetic field alignment of the milled chip-like nanoparticles of the Sm–Co and Nd–Fe–B materials. It is found that the application of magnetic fields during the ball milling strengthens the anisotropy of the chips and therefore improves the alignment. For SmCo5 phase-based chips, for instance, energy products up to 26.0 MG Oe and 19.1 MG Oe are obtained for the chips and the bonded magnets, respectively. This combined technique opens a new approach to the fabrication of anisotropic bonded magnets for various applications.
Miniaturization of electrostatic ion engines by ionization and acceleration coupling
Authors: Ferrer P , Tchonang M P
Published: August 2011

We introduce a thruster concept where the same electric field is responsible for both ionization of the neutrals and acceleration of the ions, by letting the propellant gas escape into a high-field region through a thin, hollow needle at high electric potential. Ionization occurs via the corona mechanism. The configuration is very similar to the FEEP, the difference being in the ionization mechanism and the use of gaseous propellant. Although tests showed that such a thruster only ionizes a small fraction of the neutral gas (<1%), the ions nevertheless impart a great deal of momentum to the plume, creating an ionic wind. We propose a model to estimate the electric behaviour of the system. A proof-of-concept thruster was tested, whose mass was <5 g, operating around 1500 V at thrust levels of 330 (±75) µN, consuming ∼1.5 W and using air as a propellant. Comparison of electrical data with the models showed decent agreement. The tests were only suitable for initial data collection and the thruster only moderately resembled a working design, hence data such as efficiency cannot yet be meaningfully stated.
Immunogenic and tolerogenic signatures in human immunodeficiency virus (HIV)-infected controllers compared with progressors and a conversion strategy of virus control
Authors: Whittall T , Peters B , Rahman D , Kingsley C I , Vaughan R , Lehner T
Published: August 2011

Epidemiological studies have identified a small cohort of controllers of human immunodeficiency virus (HIV)-1 infection, who without treatment have no detectable virus, and others who progress at a variable rate. The objective of this study was to distinguish immune signatures in HIV controllers and progressors, by evaluating tolerogenic and immunogenic factors in untreated HIV-1 infected individuals. The recruited population was divided into putative elite controllers (PEC), long-term non-progressors (LTNP), normal progressors (NP) and fast progressors (FP). The proportion of regulatory T cells [Tregs, CD4+CD25+forkhead box P3 (FoxP3+)], programmed death (PD)-1 and cytotoxic T lymphocyte antigen (CTLA)-inhibitory molecules and CD40L, CD69 and Ki67 activation markers were evaluated in peripheral blood mononuclear cells (PBMC) by flow cytometry. Significant differences were found between HIV controllers and HIV progressors, with up-regulation of Tregs, PD-1 and CTLA-4 and decrease of CD40L expression in progressors compared with controllers. Expression of CD40L and concentrations of interleukin (IL)-6, CCL-3, and CCL-4 were significantly higher in PEC and LTNP than in NP and FP. In an attempt to convert immune signatures of progressors to those of controllers, seven agents were used to stimulate PBMC from the four cohorts. Treatment with CD40L and IL-4 or PD-1 antibodies in vitro were most effective in converting the immune signatures of progressors to those observed in controllers by down-regulating Tregs and up-regulating CD40L expression in CD4+ T cells. The conversion concept merits translation to in vivo immune control of HIV infection.
Testing for allocation efficiencies in water quality tenders across catchments, industries and pollutants: a north Queensland case study*
Authors: Rolfe John , Greiner Romy , Windle Jill , Hailu Atakelty
Published: August 2011

The design of competitive tenders to purchase environmental services requires judgements to be made about the funding scale and tender scope, with the latter incorporating considerations of geographic area, industries involved and the types of environmental outputs required. Increasing the scale and scope of tenders increases the likelihood that a larger range of proposals will be proposed and cost‐effective ones selected. However, the use of larger and more broadly scoped tenders may reduce landholder participation and increase asking bids. In the study reported here, these issues have been tested with a single water quality tender run in north‐eastern Australia in 2007 and 2008. Post hoc tests and workshop exercises show that while larger‐scale and scope tenders can generate efficiency gains, care has to be taken to maintain participation and avoid higher bid levels.
On approximation of the Laplace–Beltrami operator and the Willmore energy of surfaces
Authors: Hildebrandt Klaus , Polthier Konrad
Published: August 2011

Discrete Laplace–Beltrami operators on polyhedral surfaces play an important role for various applications in geometry processing and related areas like physical simulation or computer graphics. While discretizations of the weak Laplace–Beltrami operator are well‐studied, less is known about the strong form. We present a principle for constructing strongly consistent discrete Laplace–Beltrami operators based on the cotan weights. The consistency order we obtain, improves previous results reported for the mesh Laplacian. Furthermore, we prove consistency of the discrete Willmore energies corresponding to the discrete Laplace–Beltrami operators.
VASE: Volume‐Aware Surface Evolution for Surface Reconstruction from Incomplete Point Clouds
Authors: Tagliasacchi Andrea , Olson Matt , Zhang Hao , Hamarneh Ghassan , Cohen‐Or Daniel
Published: August 2011

Objects with many concavities are difficult to acquire using laser scanners. The highly concave areas are hard to access by a scanner due to occlusions by other components of the object. The resulting point scan typically suffers from large amounts of missing data. Methods that use surface‐based priors rely on local surface estimates and perform well only when filling small holes. When the holes become large, the reconstruction problem becomes severely under‐constrained, which necessitates the use of additional reconstruction priors. In this paper, we introduce weak volumetric priors which assume that the volume of a shape varies smoothly and that each point cloud sample is visible from outside the shape. Specifically, the union of view‐rays given by the scanner implicitly carves the exterior volume, while volumetric smoothness regularizes the internal volume. We incorporate these priors into a surface evolution framework where a new energy term defined by volumetric smoothness is introduced to handle large amount of missing data. We demonstrate the effectiveness of our method on objects exhibiting deep concavities, and show its general applicability over a broader spectrum of geometric scenario.
Gender Differences and Anti-School Boys
Authors: Abraham John
Published: August 2011

This paper explores and contrasts the gender value systems of two groups of anti-school boys. It suggests that cultural differences in specifically gender values can lead to (i) polarisation between anti-school boys and (ii) confrontation with school authorities in ways not explained by the traditional theory of culture clash between the working class pupil and the middle class school. It is also noted that the label ‘counter-school’ used by Willis to convey the culture of some working class boys (‘the lads’) may need to be refined if the culture is reassessed in a way which acknowledges the commonality between the gender value systems of ‘the lads’ and those of the school. In fact, the research reported in this paper found that another group of anti-school boys (not working class) was much more counter the gender value system of the school than ‘the lads’ and did not uphold traditional masculine values.