bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlations in V1 Are Reduced by Stimulation Outside the Receptive Field
Authors: Snyder Adam C. , Morais Michael J. , Kohn Adam , Smith Matthew A.
Published: September 2014

The trial-to-trial response variability of nearby cortical neurons is correlated. These correlations may strongly influence population coding performance. Numerous studies have shown that correlations can be dynamically modified by attention, adaptation, learning, and potent stimulus drive. However, the mechanisms that influence correlation strength remain poorly understood. Here we test whether correlations are influenced by presenting stimuli outside the classical receptive field (RF) of visual neurons, where they recruit a normalization signal termed surround suppression. We recorded simultaneously the activity of dozens of cells using microelectrode arrays implanted in the superficial layers of V1 in anesthetized, paralyzed macaque monkeys. We presented annular stimuli that encircled—but did not impinge upon—the RFs of the recorded cells. We found that these “extra-classical” stimuli reduced correlations in the absence of stimulation of the RF, closely resembling the decorrelating effects of stimulating the RFs directly. Our results suggest that normalization signals may be an important mechanism for modulating correlations.
Tat 101-Mediated Enhancement of Brain Pericyte Migration Involves Platelet-Derived Growth Factor Subunit B Homodimer: Implications for Human Immunodeficiency Virus-Associated Neurocognitive Disorders
Authors: Niu Fang , Yao Honghong , Zhang Wenting , Sutliff Roy Lee , Buch Shilpa
Published: September 2014

In the era of antiretroviral therapy, although the human immunodeficiency virus (HIV) replication can be successfully controlled, complications of the CNS continue to affect infected individuals. Viral Tat protein is not only neurotoxic but has also been shown to disrupt the integrity of the blood–brain barrier (BBB). Although the role of brain microvascular endothelial cells and astrocytes in Tat-mediated impairment has been well documented, pericytes, which are important constituents of the BBB and play a key role in maintaining the integrity of the barrier, remain poorly studied in the context of HIV-associated neurocognitive disorders (HAND). In the present study, we demonstrated that exposure of human brain microvascular pericytes and C3H/10T1/2 cells to HIV-1 Tat101 resulted in increased expression of platelet-derived growth factor subunit B homodimer (PDGF-BB) and increased migration of the treated cells. Furthermore, we also demonstrated that this effect of Tat was mediated via activation of mitogen-activated protein kinases and nuclear factor-κB pathways. Secreted PDGF-BB resulted in autocrine activation of the PDGF-BB/PDGF β receptor signaling pathway, culminating ultimately into increased pericyte migration.Ex vivorelevance of these findings was further corroborated in isolated microvessels of HIV Tg26 mice that demonstrated significantly increased expression of PDGF-BB in isolated brain microvessels with a concomitant loss of pericytes. Intriguingly, loss of pericyte coverage was also detected in sections of frontal cortex from humans with HIV-encephalitis compared with the uninfected controls. These findings thus implicate a novel role of PDGF-BB in the migration of pericytes, resulting in loss of pericyte coverage from the endothelium with a subsequent breach of the BBB.
Integration of Multiple Determinants in the Neuronal Computation of Economic Values
Authors: Raghuraman Anantha P. , Padoa-Schioppa Camillo
Published: September 2014

Economic goods may vary on multiple dimensions (determinants). A central conjecture in decision neuroscience is that choices between goods are made by comparing subjective values computed through the integration of all relevant determinants. Previous work identified three groups of neurons in the orbitofrontal cortex (OFC) of monkeys engaged in economic choices: (1) offer value cells, which encode the value of individual offers; (2) chosen value cells, which encode the value of the chosen good; and (3) chosen juice cells, which encode the identity of the chosen good. In principle, these populations could be sufficient to generate a decision. Critically, previous work did not assess whether offer value cells (the putative input to the decision) indeed encode subjective values as opposed to physical properties of the goods, and/or whether offer value cells integrate multiple determinants. To address these issues, we recorded from the OFC while monkeys chose between risky outcomes. Confirming previous observations, three populations of neurons encoded the value of individual offers, the value of the chosen option, and the value-independent choice outcome. The activity of both offer value cells and chosen value cells encoded values defined by the integration of juice quantity and probability. Furthermore, both populations reflected the subjective risk attitude of the animals. We also found additional groups of neurons encoding the risk associated with a particular option, the risky nature of the chosen option, and whether the trial outcome was positive or negative. These results provide substantial support for the conjecture described above and for the involvement of OFC in good-based decisions.
Fast Phasic Release Properties of Dopamine Studied with a Channel Biosensor
Authors: Kress Geraldine J. , Shu Hong-Jin , Yu Andrew , Taylor Amanda , Benz Ann , Harmon Steve , Mennerick Steven
Published: September 2014

Few other neurotransmitters are of as intense interest to neuropsychiatry and neurology as dopamine, yet existing techniques to monitor dopamine release leave an important spatiotemporal gap in our understanding. Electrochemistry and fluorescence imaging tools have been developed to fill the gap, but these methods have important limitations. We circumvent these limitations by introducing a dopamine-gated chloride channel into rat dorsal striatal medium spiny neurons, targets of strong dopamine innervation, thereby transforming dopamine from a slow transmitter into a fast transmitter and revealing new opportunities for studying moment-to-moment regulation of dopamine release. We demonstrate pharmacological and biophysical properties of the channel that make it suitable for fast, local dopamine measurements, and we demonstrate for the first time spontaneous and evoked responses to vesicular dopamine release in the dorsal striatum. Evoked dopamine currents were separated into a fast, monosynaptic component and a slower-rising and decaying disynaptic component mediated by nicotinic receptor activation. In summary, LGC-53 represents a dopamine biosensor with properties suitable for temporal separation of distinct dopamine signals in targets of dopamine innervation.
Spatial Irregularities of Sensitivity along the Organ of Corti of the Cochlea
Authors: Temchin Andrei N. , Ruggero Mario A.
Published: September 2014

Fine structures of spatial profiles were computed from existing records of cat and chinchilla auditory-nerve fibers on the basis of their characteristic frequencies and cochlear maps. The spatial fine structures of characteristic-frequency thresholds and of “spontaneous” and driven firing rates were mutually correlated, implying the presence of sensitivity fluctuations due to spatial irregularities of presynaptic structures or processes of the inner hair cells and their input. These findings suggest that activity that appears spontaneous is not actually spontaneous and may indicate irregularities of tonotopic mapping in cochlear mechanics.
Clone Mapper: An Online Suite of Tools for RNAi Experiments in Caenorhabditis elegans
Authors: Thakur Nishant , Pujol Nathalie , Tichit Laurent , Ewbank Jonathan J
Published: September 2014

RNA interference (RNAi), mediated by the introduction of a specific double-stranded RNA, is a powerful method to investigate gene function. It is widely used in the Caenorhabditis elegans research community. An expanding number of laboratories conduct genome-wide RNAi screens, using standard libraries of bacterial clones each designed to produce a specific double-stranded RNA. Proper interpretation of results from RNAi experiments requires a series of analytical steps, from the verification of the identity of bacterial clones, to the identification of the clones’ potential targets. Despite the popularity of the technique, no user-friendly set of tools allowing these steps to be carried out accurately, automatically, and at a large scale, is currently available. We report here the design and production of Clone Mapper, an online suite of tools specifically adapted to the analysis pipeline typical for RNAi experiments with C. elegans. We show that Clone Mapper overcomes the limitations of existing techniques and provide examples illustrating its potential for the identification of biologically relevant genes. The Clone Mapper tools are freely available via http://www.ciml.univ-mrs.fr/EWBANK_jonathan/software.html.
Multiple crack identification in stepped beam by measurements of natural frequencies
Authors: Khiem Nguyen Tien , Hung Duong The , Ninh Vu Thi An
Published: September 2014

A new approach is proposed for calculating natural frequencies and crack detection in a stepped cantilever beam with arbitrary number of cracks. This is based an explicit expression of the natural frequencies in term of crack parameter derived in the form similar to the so-called Rayleigh quotient for vibrating beam. The obtained simple relationship between natural frequencies and crack parameters enables not only accurate calculating the natural frequencies but also to develop an efficient procedure for detecting multiple cracks from given natural frequencies. The proposed technique called crack scanning method is illustrated and validated by numerical results.
PRINCIPALITIES, POWERS, AND FOOLS DOES PREACHING MAKE AN ETHICAL DIFFERENCE
Authors: Campbell Charles L.
Published: September 2014

This paper is the text of a keynote speech delivered at the eighth international conference of Societas Homiletica, held in Copenhagen, Denmark, 19-25 July 2008. The conference theme was “In search for meaning: does preaching make a difference?” This paper along with the response paper by Johan Cilliers, also in this issue of Homiletic, will be published along with the other papers from the conference in the forthcoming book of papers published by Societas Homiletica. Used with permission.
Are Congregations Texts?
Authors: Hearlson Adam
Published: September 2014

It is a common sentiment among homileticians that preaching requires exegeting both the scriptural text and the congregational context. The relevancy of the preaching message, it is argued, depends in part upon a deep knowledge of the congregational culture. The preacher is therefore encouraged to “read” the culture of the congregation and discern how the symbols, practices, and actions of the congregation are used to make meaning so that the preacher might construct a fitting sermon. In this way, the congregation is likened to a text that awaits a reading by a literate observer. In this paper, I examine the limitations of such an analogy arguing that while a semiotic approach to congregations has merit it is often blind to the ways in which power and production influence the creation and reproduction of the congregational culture. Finally, the paper concludes with descriptions from recent homiletical works that offer productive alternatives to the semiotic approach to congregational study.
Joseph Blenkinsopp, David Remembered: Kingship and National Identity in Ancient Israel
Authors: Woodruff Shelley Hasty
Published: September 2014

N/A
Richard Horsley and Tom Thatcher, John, Jesus, and the Renewal of Israel
Authors: Park Sam
Published: September 2014

N/A
Debra J. Mumford, Exploring Prosperity Preaching: Biblical Health, Wealth, and Wisdom
Authors: Jon Song Bok (Bob)
Published: September 2014

N/A
Ruth C. Duck, Worship for the Whole People of God: Vital Worship for the 21st Century
Authors: Yang Sunggu
Published: September 2014

N/A
Lead tolerance of water hyacinth (Eichhornia crassipes Mart. - Pontederiaceae) as defined by anatomical and physiological traits
Authors: PEREIRA FABRICIO J. , CASTRO EVARISTO M. DE , OLIVEIRA CYNTHIA DE , PIRES MARINÊS F. , PEREIRA MARCIO P. , RAMOS SILVIO J. , FAQUIN VALDEMAR
Published: September 2014

This study aimed at verifying the lead tolerance of water hyacinth and at looking at consequent anatomical and physiological modifications. Water hyacinth plants were grown on nutrient solutions with five different lead concentrations: 0.00, 0.50, 1.00, 2.00 and 4.00 mg L–1 by 20 days. Photosynthesis, transpiration, stomatal conductance and the Ci/Ca rate were measured at the end of 15 days of experiment. At the end of the experiment, the anatomical modifications in the roots and leaves, and the activity of antioxidant system enzymes, were evaluated. Photosynthetic and Ci/Ca rates were both increased under all lead treatments. Leaf anatomy did not exhibit any evidence of toxicity effects, but showed modifications of the stomata and in the thickness of the palisade and spongy parenchyma in the presence of lead. Likewise, root anatomy did not exhibit any toxicity effects, but the xylem and phloem exhibited favorable modifications as well as increased apoplastic barriers. All antioxidant system enzymes exhibited increased activity in the leaves, and some modifications in roots, in the presence of lead. It is likely, therefore, that water hyacinth tolerance to lead is related to anatomical and physiological modifications such as increased photosynthesis and enhanced anatomical capacity for CO2 assimilation and water conductance.
Obesity, insulin resistance and comorbidities ? Mechanisms of association
Authors: Castro Ana Valeria B. , Kolka Cathryn M. , Kim Stella P. , Bergman Richard N.
Published: September 2014

Overall excess of fat, usually defined by the body mass index, is associated with metabolic (e.g. glucose intolerance, type 2 diabetes mellitus (T2DM), dyslipidemia) and non-metabolic disorders (e.g. neoplasias, polycystic ovary syndrome, non-alcoholic fat liver disease, glomerulopathy, bone fragility etc.). However, more than its total amount, the distribution of adipose tissue throughout the body is a better predictor of the risk to the development of those disorders. Fat accumulation in the abdominal area and in non-adipose tissue (ectopic fat), for example, is associated with increased risk to develop metabolic and non-metabolic derangements. On the other hand, observations suggest that individuals who present peripheral adiposity, characterized by large hip and thigh circumferences, have better glucose tolerance, reduced incidence of T2DM and of metabolic syndrome. Insulin resistance (IR) is one of the main culprits in the association between obesity, particularly visceral, and metabolic as well as non-metabolic diseases. In this review we will highlight the current pathophysiological and molecular mechanisms possibly involved in the link between increased VAT, ectopic fat, IR and comorbidities. We will also provide some insights in the identification of these abnormalities. Arq Bras Endocrinol Metab. 2014;58(6):600-9
Correlação entre ruptura de ligamento cruzado cranial e lesão de meniscomedial em cães
Authors: Dal-Bó Ísis dos Santos , Ferrigno Cássio Ricardo Auada , Caquías Daniela Fabiana Izquierdo , Nina Marcos Ishimoto Della , Ferreira Márcio Poletto , Figueiredo Adriana Valente de , Cavalcanti Renato Albuquerque de Oliveira , Santos Jaqueline França do , Ferraz Vanessa Couto de Magalhães
Published: September 2014

O presente trabalho correlacionou o tempo de ruptura do ligamento cruzado cranial (RLCCr) à lesão em menisco medial e ao tipo de lesão observada em cães tratados por estabilização dinâmica (osteotomias) ou estática (sutura fabelo-tibial). Este estudo retrospectivo avaliou os registros de 104 cães (117 joelhos). As osteotomias foram realizadas em 98 articulações, a sutura fabelo-tibial em 15 joelhos e, em 4 joelhos, foi realizada apenas artrotomia exploratória. A média de idade foi 4,5 anos, 41% dos cães eram machos e 59%, fêmeas e a média da massa corporal foi 32,7kg. Os tipos de lesão do menisco medial observados foram: tipo 1, 2, 3, 4, 6, 7 e associações dos tipos 1-4, 1-6 e 1-7. O tipo 1 foi o mais prevalente, sendo responsável por 32,5% dos casos. Não foram encontradas correlações entre a presença ou não de lesão de menisco medial e o tempo de ocorrência da RLCCr e entre o tipo de lesão de menisco medial e o tempo de RLCCr.
Ensino de História, Didática de História, Educação Histórica: alguns dados de pesquisa (2000-2005)
Authors: Evangelista Olinda , Triches Jocemara
Published: September 2014

O presente texto sistematiza informações, coligidas no site do Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), sobre grupos que pesquisam Ensino de História, Didática da História, Educação Histórica no Brasil, entre 2000 e 2005. Busca dar visibilidade a estes temas de investigação no âmbito das áreas de História e Educação. Constata a alta incidência do verbete Ensino de História; Didática da História apareceu timidamente em 2004 e Educação Histórica apenas em 2005. Verifica-se um crescimento exponencial no ano de 2004 de Grupos de Pesquisa (GP) de Ensino de História na área História e forte presença de GPs Ensino de História na área Educação. Os GPs, em sua maioria, estão sediados em instituições públicas de ensino superior e nas regiões Sul e Sudeste. A maior parte dos líderes é formada em História, tanto na graduação como na pós-graduação. Tal formação ocorreu majoritariamente na região Sudeste. Os líderes estão majoritariamente sediados em Centros de Educação ou de Ciências Humanas. A tendência acima se verifica também no que se refere às Linhas de Pesquisa nas duas áreas, constatando-se: crescimento no ano de 2004; maior presença na região Sudeste; concentração em instituições públicas. No que se refere aos dois outros verbetes - Didática da História e Educação Histórica - demonstra-se que GPs de DH apareceram em 2004 e de EH apenas em 2005. Sua presença é maior nas instituições públicas de ensino, na região sul e sudeste.
Práticas eróticas e limites da sexualidade: contribuições de estudos recentes
Authors: Gregori Maria Filomena
Published: September 2014

Este artigo examina as contribuições dos estudos antropológicos recentes feitos no Brasil sobre diferentes experiências envolvidas nos erotismos contemporâneos, sobretudo no que elas permitem decifrar articulações entre práticas sexuais, normas de gênero e limites da sexualidade (isto é, a zona fronteiriça onde habitam norma e transgressão, consentimento e abuso, prazer e dor). O balanço dessa bibliografia pretende lançar luz sobre as principais abordagens empregadas e, em particular, examinar como os prazeres e os perigos dos erotismos têm sido tratados a partir das problemáticas do consentimento, do contrato, da erotização dos corpos e, finalmente, dos riscos envolvidos nessas práticas.
Diferenças e desigualdades negociadas: raça, sexualidade e gênero em produções acadêmicas recentes
Authors: Moutinho Laura
Published: September 2014

Muitas das recentes reflexões acerca da produção da diferença e da análise da desigualdade social vêm investindo na articulação entre os chamados "marcadores sociais da diferença". Nesse amplo cenário que envolve os debates acerca dos direitos diferenciados e das políticas de reconhecimento, da produção de novas sensibilidades e da concomitante ressemantização de antigas formas de exclusão, a intersecção entre raça, nação, sexualidade e gênero ganha destaque. O objetivo deste artigo é refletir sobre a forma como um certo conjunto de marcadores da diferença vem sendo agenciado em reflexões acadêmicas e políticas recentes. Mais especificamente, este artigo irá focar três eixos: 1) o da (re)construção dos Estados nacionais e de certas representações de nação; 2) o campo dos direitos humanos: da regulação à construção de sujeitos de direitos; e 3) o das identidades subjetivas, do espaço de agência, do cuidado de si e da inserção em novas ou renovadas redes de sociabilidade.
Biografia do Orvalho: considerações sobre narrativa, vida e pesquisa em Educação Matemática
Authors: Fernandes Filipe Santos
Published: September 2014

Neste texto, buscamos articular três temas: a narrativa, a vida e a pesquisa em Educação Matemática. Atravessados por uma discussão junto à poesia de Manoel de Barros e a diversos autores contemporâneos, destacamos, em termos filosóficos, metodológicos e históricos, os encantamentos e perigos da mobilização de narrativas de vida, em suas mais variadas formas, na pesquisa em ciências humanas. Ao final, pretendemos que as discussões apresentadas sejam um convite para novos modos de se praticar a pesquisa e, como que em uma reverberação, a pesquisa em Educação Matemática.
[NO TITLE AVAILABLE]
Authors: Neves Frederico de Castro
Published: September 2014

Este artigo procura analisar as mudanças ocorridas nas concepções sobre a caridade nos anos iniciais do século XX, no Brasil, especialmente com relação aos pobres camponeses deslocados pela seca, chamados de retirantes. As fontes são principalmente jornais, relatórios e depoimentos de contemporâneos, assim como partes diárias da Polícia da capital do Ceará. As posições da Igreja Católica e do Estado são confrontadas com movimentos dos próprios retirantes, que interpretam de diferentes maneiras as concepções sobre a caridade e o crime, exigindo, em resposta, transformações nas políticas de assistência aos pobres.
SEROLOGICAL SCREENING FOR INFECTIOUS CATTLE DISEASES: I. INFLUENCE OF REPRODUCTIVE STATUS
Authors: Barajas-Rojas Jose Alfonso , Riemann Hans , Franti Charles
Published: September 2014

A cohort of 125 cows (Zebu-Holstein crosses) were screened every two months during a period of two years for IgG antibodies to 20 viral, bacterial, rickettsial and parasitic agents. The screening was performed on sera using the ELISA procedure. The IgG levels fluctuated during pregnancy in a regular and similar way for all the antigens tested. IgG reached its lowest levels in the fourth and seventh month of pregnancy, a significant increase ocurred during the last month of pregnancy and this was followed by a precipitous decline during the first month post partum. The IgG fluctuations associated with the different phases of reproductive status may interact with seasonal changes in IgG levels. The changes in IgG levels during pregnancy may have the result that an individual animal oscillates between being seropositive and seronegative. This can have an important impact on serological studies of abortion epidemiology.
CONSÓRCIO DE SUBSTITUIÇÃO DE CULTURAS: ALTERNATIVA PARA A PEQUENA PROPRIEDADE RURAL
Authors: Trezzi Michelangelo Müzell , Silva Paulo Regis Ferreira da
Published: September 2014

No consórcio de substituição de culturas uma segunda cultura é implantada após a primeira ter atingido a antese, mas antes da colheita, ocorrendo menor competição por recursos do ambiente entre as culturas do que no consórcio simultâneo. Por requerer a semeadura manual da segunda cultura a ser implantada, similarmente ao plantio direto, proporciona melhor conservação da umidade e controle da erosão, além de manter a temperatura do solo mais favorável em relação ao sistema de sucessão. Além disso, o efeito do sombreamento exercido pelas folhas remanescentes da primeira cultura pode dificultar o desenvolvimento de ervas daninhas nos estádios iniciais da segunda espécie. No Rio Grande do Sul, diversas culturas apresentam potencial para uso em consórcio de substituição. Para que haja sucesso na sua utilização, entretanto, deve-se ter cuidados com relação à utilização de espécies e cultivares compatíveis, arranjo de plantas adequado, escolha de época apropriada para introdução da segunda cultura e controle eficiente de plantas daninhas durante o desenvolvimento da primeira cultura.
EFEITO DA COMBINAÇÃO DA SILAGEM DE AVEIA EMURCHECIDA E DA SILAGEM DE MILHO, NO DESEMPENHO DE NOVILHOS EM CONFINAMENTO
Authors: Nostre Frederico Taques , Brondam Ivan Luiz
Published: September 2014

RESUMO O experimento constou de três tratamentos: T1 - silagem de milho mais concentrado mais uréia; T2- silagem de milho (70%) mais silagem de aveia (Avena strigosa, Screb.) emurchecida (30%) mais concentrado mais uréia; T3- silagem de milho (40%) mais silagem de aveia (60%) mais concentrado. O concentrado utilizado foi de igual composição e as quantidades médias utilizadas nas dietas foram as seguintes: 31,35; 33,34 e 32,28%, para T1, T2 e T3 respectivamente. A uréia acondicionada aos tratamentos T1 e T2 teve como função tornar os tratamentos isonitrogenados (12% de Proteína Bruta). Foram utilizados 18 novilhos da raça Canchin, com idade média de 24 meses e peso médio inicial de 377kg. Os animais foram mantidos sob regime de confinamento durante 84 dias, com adaptação de 39 dias. O ganho médio diário de peso foi de 1,05; 0,87 e 0,85kg para T1, T2 e T3 (P > 0,20468), respectivamente. O consumo diário de matéria seca foi de 9,54; 9,50 e 8,67kg (P > 0,18363) e a conversão alimentar foi de 9,77; 11,36 e 10,62 (P > 0,05) respectivamente. Conclui-se que a adição de silagem de aveia emurchecida, na alimentação dos animais, não proporcionou diferença significativa em relação às variáveis estudadas.
Underground coal gasification: issues in commercialisation
Authors: Walker Leonard Keith
Published: September 2014

Back in 2007, it was expected that commercial gas production from underground coal gasification (UCG) technology would be in progress within the following 5 years. This has not occurred, particularly in Australia, where at the time three commercial projects were being aggressively pursued. This paper reviews each of five key issues that may be considered to have delayed UCG commercialisation. Of these, it is concluded that the primary factor is the use of government environmental policy to achieve its preferred energy outcomes, as in the development of the coal seam gas industry in Australia. It is concluded that the UCG industry must select appropriate markets and utilise small-scale financially viable projects to achieve its required commercial breakthrough.
Freeze–thaw resistance of normal strength powder concretes
Authors: Tikkanen Johanna , Cwirzen Andrzej , Penttala Vesa
Published: September 2014

The effects of mineral powders on scaling, water absorption and internal deterioration of concretes are studied. Properties of a reference concrete produced with Portland cement are compared with corresponding mineral powder concretes. In the mineral powder concretes the Portland cement is replaced by 10 or 20 wt% by either limestone or quartz powder. Some mixes also contain a further addition of 10 and 20 wt% of these powders to the Portland cement. Surface scaling and internal damage tests and a capillary suction test are performed on the concretes, to obtain a basic understanding of the freeze–thaw durability of the mineral powder concretes. The results suggest that the use of mineral powders itself does not have an effect on the freeze–thaw resistance, but the consequent binder reduction and loss of strength impairs durability. The loss of strength resulting from the replacement of the cement and the consequent reduction in the freeze–thaw durability might be compensated for by reducing the water/cement (w/c) ratio of the mineral powder concretes. This may be possible because the use of mineral powders increases the flow, that is, reduces the water demand of the test concretes.
A late‐Quaternary perspective on atmospheric pCO2, climate, and fire as drivers of C4‐grass abundance
Authors: Urban Michael A. , Nelson David M. , Street-Perrott F. Alayne , Verschuren Dirk , Hu Feng Sheng
Published: September 2014

Various environmental factors, including atmospheric CO2 (pCO2), regional climate, and fire, have been invoked as primary drivers of long‐term variation in C4 grass abundance. Evaluating these hypotheses has been difficult because available paleorecords often lack information on past C4 grass abundance or potential environmental drivers. We analyzed carbon isotope ratios (δ13C) of individual grains of grass pollen in the sediments of two East African lakes to infer changes in the relative abundance of C3 vs. C4 grasses during the past 25 000 years. Results were compared with concurrent changes in pCO2, temperature, moisture balance, and fire activity. Our grass‐pollen δ13C analysis reveals a dynamic history of grass‐dominated vegetation in equatorial East Africa: C4 grasses have not consistently dominated lowland areas, and high‐elevation grasses have not always been predominantly C3. On millennial timescales, C4 grass abundance does not correlate with charcoal influx at either site, suggesting that fire was not a major proximate control of the competitive balance between C3 and C4 grasses. Above the present‐day treeline on Mt. Kenya, C4 grass abundance declined from an average of ~90% during the glacial period to less than ~60% throughout the Holocene, coincident with increases in pCO2 and temperature, and shifts in moisture balance. In the lowland savanna southeast of Mt. Kilimanjaro, C4 grass abundance showed no such directional trend, but fluctuated markedly in association with variation in rainfall amount and seasonal‐drought severity. These results underscore spatiotemporal variability in the relative influence of pCO2 and climate on the interplay of C3 and C4 grasses and shed light on an emerging conceptual model regarding the expansion of C4‐dominated grasslands in Earth's history. They also suggest that future changes in the C3/C4 composition of grass‐dominated ecosystems will likely exhibit striking spatiotemporal variability as a result of varying combinations of environmental controls.
What Is the Best Predictor for Oral Cleanliness After Brushing? Results From an Observational Cohort Study
Authors: Harnacke Daniela , Winterfeld Tobias , Erhardt Jörg , Schlueter Nadine , Ganss Carolina , Margraf‐Stiksrud Jutta , Deinzer Renate
Published: September 2014

Background: Brushing performance is an important factor for brushing success. Thus, observing brushing performance might help to explain deficits in oral hygiene. However, it is unknown how brushing behavior observed at one time relates to brushing capabilities observed at another time. The authors assessed the predictive validity of video‐observed habitual brushing behavior for the capability to achieve oral cleanliness several weeks later.

Methods: Study participants (N = 101) were video‐recorded while cleaning their teeth. Two independent, calibrated examiners assessed brushing duration, evenness of distribution of brushing time across areas of the mouth as one indicator of brushing systematics, and duration of specific brushing movements. Weeks later (mean: 6.4 weeks; range: 1 to 24 weeks), 70 participants were asked to remove plaque to the best of their ability, and degree of oral cleanliness was assessed immediately afterward. A forward regression analysis was performed to assess the predictive values of brushing parameters.

Results: Regression analysis revealed that evenness of distribution of brushing time and duration of circling movements explained 20.8% of variance of oral cleanliness (P <0.001).

Conclusion: Evenness of distribution of brushing time and duration of circling movements are aspects of observed habitual brushing behavior that predict brushing capabilities in terms of oral cleanliness.
Localized Aggressive Periodontitis Treatment Response in Primary and Permanent Dentitions
Authors: Merchant Sherin N. , Vovk Andrea , Kalash Danny , Hovencamp Nicole , Aukhil Ikramuddin , Harrison Peter , Zapert Edward , Bidwell John , Varnado Phyllis , Shaddox Luciana M.
Published: September 2014

Background: The comparative treatment response of children and young adults with localized aggressive periodontitis treatment (LAgP) affecting primary and permanent dentition is unknown. The objective of this study is to evaluate the influence of non‐surgical periodontal therapy with adjunctive systemic antibiotics on the clinical outcome of children and young adults with primary versus permanent dentition affected by LAgP.

Methods: A cohort of 97 African American participants aged 5 to 21 years (30 males and 67 females; 22 primary and 75 permanent dentitions affected) diagnosed with LAgP were included. Patients presented with no significant medical history. All patients underwent periodontal therapy, which consisted of full‐mouth mechanical debridement at baseline and the 3‐, 6‐, and 12‐month appointments. Additionally, all patients were prescribed a 1‐week regimen of systemic antibiotics at the initial appointment. Clinical parameters were analyzed, including probing depth, clinical attachment level (CAL), bleeding on probing, and percentage of visible plaque.

Results: Overall, periodontal therapy was found to be effective in improving the clinical outcomes of both primary and permanent dentitions. Although baseline CALs were similar between the groups, the reduction in mean CAL at 3, 6, and 12 months and reduction in percentage plaque at 3 months were significantly greater in primary dentition compared with permanent dentition.

Conclusions: Non‐surgical therapy with systemic antibiotics is effective for LAgP in both primary and permanent dentitions. A greater reduction in CAL in LAgP of primary dentition may suggest that younger children may carry a greater propensity for positive treatment outcomes and healing potential compared with children/young adults with permanent dentition.
Azithromycin Enhances Phagocytic Killing of Aggregatibacter actinomycetemcomitans Y4 by Human Neutrophils
Authors: Lai Pin‐Chuang , Schibler Mark R. , Walters John D.
Published: September 2014

Background: Aggregatibacter actinomycetemcomitans resists killing by neutrophils and is inhibited by azithromycin (AZM) and amoxicillin (AMX). AZM actively concentrates inside host cells, whereas AMX enters by diffusion. The present study is conducted to determine whether AZM is more effective than AMX at enhancing phagocytic killing of A. actinomycetemcomitans by neutrophils.

Methods: Killing assays were conducted in the presence of either 2 μg/mL AZM or 16 μg/mL AMX (equipotent against A. actinomycetemcomitans). Neutrophils were loaded by incubation with the appropriate antibiotic. Opsonized A. actinomycetemcomitans strain Y4 was incubated with the indicated antibiotic alone, with loaded neutrophils and antibiotic, or with control neutrophils (without antibiotic) at multiplicities of infection (MOIs) of 30 and 90 bacteria per neutrophil.

Results: Neutrophil incubation with 2 μg/mL AZM yielded an intracellular concentration of 10 μg/mL. At an MOI of 30, neutrophils loaded with AZM failed to kill significantly more bacteria than control neutrophils during the 60‐ and 90‐minute assay periods. At an MOI of 90, neutrophils loaded with AZM killed significantly more bacteria than either AZM alone or control neutrophils during 60‐ and 90‐minute incubations (P <0.05), and killed significantly more bacteria after 90 minutes than the sum of the killing produced by AZM alone or neutrophils alone. Neutrophils incubated with AMX under identical conditions also killed significantly more bacteria than either AMX alone or control neutrophils, but there was no evidence of synergism between AMX and neutrophils.

Conclusions: Neutrophils possess a concentrative transport system for AZM that may enhance killing of A. actinomycetemcomitans. Its effects are most pronounced when neutrophils are greatly outnumbered by bacteria.
Fluid Shear Stress Stimulates Osteogenic Differentiation of Human Periodontal Ligament Cells via the Extracellular Signal‐Regulated Kinase 1/2 and p38 Mitogen‐Activated Protein Kinase Signaling Pathways
Authors: Tang Min , Peng Zhuli , Mai Zhihui , Chen Lin , Mao Qin , Chen Zheng , Chen Qi , Liu Limin , Wang Yuxuan , Ai Hong
Published: September 2014

Background: Fluid shear stress (FSS) is a major type of mechanical stress that is loaded on human periodontal ligament cells (hPDLCs) during mastication and orthodontic tooth movement. This study aims to clarify the effect of FSS on the osteogenic differentiation of hPDLCs and to further verify the involvement of mitogen‐activated protein kinase (MAPK) signaling in this process.

Methods: After isolation and characterization, hPDLCs were subjected to 2‐hour FSS at 12 dynes/cm2, and cell viability, osteogenic gene mRNA expression, alkaline phosphatase (ALP) activity, secretion of Type I collagen (COL‐I), and calcium deposition were assayed. The levels of phosphorylated p38 and phosphorylated extracellular signal‐regulated kinase 1/2 (ERK1/2) in response to FSS were detected by Western blot, and the involvement of ERK1/2 and p38 MAPK signaling pathways in hPDLC osteogenesis under FSS was investigated using the specific MAPK inhibitors U0126 (2Z,3Z)‐2,3‐bis[amino(2‐aminophenylthio)methylene]succinonitrile,ethanol) and SB203580 (4‐[4‐(4‐fluorophenyl)‐2‐(4‐[methylsulfinyl]phenyl)‐1H‐imidazol‐5‐yl]pyridine).

Results: The application of FSS on hPDLCs induced an early morphologic change and rearrangement of filamentous actin. ALP activity, messenger RNA (mRNA) levels of osteogenic genes, COL‐I, and osteoid nodules were significantly increased by FSS. Moreover, ERK1/2 and p38 were activated in different ways after FSS exposure. U0126 and SB203580 completely blocked the FSS‐induced increases in ALP activity and osteogenic gene mRNA expression and osteoid nodules formation.

Conclusions: FSS is an effective approach for stimulating osteogenic differentiation of hPDLCs. The ERK1/2 and p38 MAPK signaling pathways are involved in this cellular process.
A Study of Multiphase Flow Behavior in Vertical Oil Wells: Part I—Theoretical Treatment
Authors: Hasan A. R. , Kabir C. S.
Published: September 2014

Many models and correlations exist to predict pressure gradient in vertical two- or three-phase flow in oilwells. Most of these are develeoped from large experimental data bases, relying almost entirely on empiricism, thereby making extrapolation hazardous. The calculation procedure involved in these correlations are also rather complicated. Experience indicate that a sound model must be mechanistically based and be capable of accounting for the various flow patterns associated with multi phase flow. The predictive methods of Orkiszewski, Aziz et al., and Chierici et al. do take into account the four main flow regimes – bubbly, slug, churn and annular – and propose separate correlations for pressure drop in each flow regime. Recent developments in multiphase flow, especially in predicting flow pattern transitions and entrainment estimation during annular flow, necessitate a fresh look at the problem.

In the first part of this two-paper set, we present a theoretical model for predicting pressure drop during multiphase flow. Model development consists of studying the hydrodynamic conditions that give rise to the various flow pattern transitions. The method for estimating pressure drop in each flow regime is then developed. In developing the equations for pressure gradient, the contribution of the static head, the frictional loss, and the kinetic energy loss are examined. This aspect of the study points out the importance of the static head term and the necessity of estimating the insitu gas void fraction accurately.

Laboratory data, gathered by us and others, are presented in support of the proposed model. The agreement between the theory and experimental works is excellent. Field verification of the model and its comparison with existing correlations are the subjects of the second part of the paper.
Use and Misuse of Pendulum Arbitration in Expert Redetermination of Tract Participation
Authors: Worthington Paul F.
Published: September 2014

Over the past two decades, pendulum arbitration has been increasingly incorporated into dispute-resolution procedures for the redetermination of tract participation (equity) for unitized oil and gas fields that straddle domestic license boundaries or international borders. In such cases, the pendulum has been prescribed for use in expert redetermination, ideally so that an expert determines tract participation and then selects the closer submission made by one of the parties. The tract participation of the selected submission then constitutes the expert's final decision. The process can function reasonably well in the originally envisaged situations (e.g., two opposing cases each originating from one of two straddled license areas). It is much more difficult to apply in the more-complex situations to which it has been extrapolated subsequently. These include multiphase reservoirs with separately unitized fluids, several straddled license areas, and the use of the same subsurface model for both field-development and equity-redetermination purposes. An analysis of such situations has allowed the further identification of those circumstances for which the pendulum can be applied meaningfully in expert redetermination and those for which it should not be adopted. These additional expectations include a meaningful basis for tract participation in terms of one (equivalent) unit substance, fully prescribed technical procedures leading to a compliant reservoir model, and a single (as opposed to a staged) expert redetermination that post-dates the parties' submissions but allows for rebuttal in the event of manifest error. Case histories illustrate the difficulties that can arise where these principles are infringed. They also reaffirm the overarching message that each straddling field situation differs from others and therefore every redetermination of tract participation must be assessed separately and thoroughly.
Perceived Health Status of Women with Knee Osteoarthritis: A Cross-Sectional Study of the Relationships of Age, Body Mass, Pain and Walking Limitations
Authors: R Marks
Published: September 2014

Persons with knee osteoarthritis (OA) often experience considerable physical disability. Although some studies suggest women with this condition suffer more than men, few have attempted to characterize the magnitude and that impact of this condition specifically among women with moderate knee osteoarthritis as well as the relationships that exist between their perceived health status and well established physical, emotional and perceptual factors found in this disease. This exploratory study strove to better understand factors that underpin the perceived impact of the condition, and to describe the extent of pain and function among women with mild to moderate knee osteoarthritis, and how this impacts this condition. The records of 20 women with the condition who had undergone multiple tests using a standardized protocols and validated instruments were examined. The primary outcome measure was the perceived impact of the disease using the Arthritis Impact Measurement Scale. Secondary outcome measures included six minute walking distance, fastest walking velocity, self-reported pain, pain and functional self-efficacy, body mass, and depression. The variables were subjected to t-tests, and correlational analyses. Results demonstrated pain is the clinical factor most consistently impacting the disease experience, along with deficiencies in walking ability (p <0.05). Important mediating variables of ambulatory capacity were body mass and pain self-efficacy.
A small library of 4-(alkylamino)-3-nitrocoumarin derivatives with potent antimicrobial activity against gastrointestinal pathogens
Authors: Radulovic Niko , Stojanovic-Radic Zorica , Stojanovic Predrag , Stojanovic Nikola , Dekic Vidoslav , Dekic Biljana
Published: September 2014

Due to a confirmed antimicrobial activity of both natural and synthetic
coumarin derivatives, the present study was envisaged to provide a further
insight into the antimicrobial potential of coumarins through a screening of
a designed library of nine 4-(alkylamino)-3-nitrocoumarins against a panel of
24 laboratory strains and resistant (isolates) bacterial and fungal
pathogens. All compounds showed some degree of strain-selective activity,
that was, in some cases, very pronounced, reaching the value of 0.04 nmol/ml
(i.e. 12 ng/ml) for the minimal inhibitory concentration against Candida
albicans. The observed activity was higher against Gram-negative strains,
among which the most susceptible strain, among both ATCC strains and clinical
isolates, was Salmonella enteritidis. These results point out to a high
potential of these coumarins as antimicrobials for the treatment of
gastrointestinal and other infections caused by highly resistant microbial
strains. Finally, a multivariate statistical analysis of the herein obtained
and previous results on the antimicrobial activity of related selected
coumarins was performed to allow an easier structure-activity discussion.
Glucocorticoids Transcriptionally Regulate miR-27b Expression Promoting Body Fat Accumulation Via Suppressing the Browning of White Adipose Tissue
Authors: Kong Xiaocen , Yu Jing , Bi Jianhua , Qi Hanmei , Di Wenjuan , Wu Lin , Wang Long , Zha Juanmin , Lv Shan , Zhang Feng , Li Yan , Hu Fang , Liu Feng , Zhou Hong , Liu Juan , Ding Guoxian
Published: September 2014

Long-term glucocorticoid (GC) treatment induces central fat accumulation and metabolic dysfunction. We demonstrate that microRNA-27b (miR-27b) plays a central role in the pathogenesis of GC-induced central fat accumulation. Overexpression of miR-27b had the same effects as dexamethasone (DEX) treatment on the inhibition of brown adipose differentiation and the energy expenditure of primary adipocytes. Conversely, antagonizing miR-27b function prevented DEX suppression of the expression of brown adipose tissue–specific genes. GCs transcriptionally regulate miR-27b expression through a GC receptor–mediated direct DNA-binding mechanism, and miR-27b suppresses browning of white adipose tissue (WAT) by targeting the three prime untranslated region of Prdm16. In vivo, antagonizing miR-27b function in DEX-treated mice resulted in the efficient induction of brown adipocytes within WAT and improved GC-induced central fat accumulation. Collectively, these results indicate that miR-27b functions as a central target of GC and as an upstream regulator of Prdm16 to control browning of WAT and, consequently, may represent a potential target in preventing obesity.
Assessment of β-Cell Mass and α- and β-Cell Survival and Function by Arginine Stimulation in Human Autologous Islet Recipients
Authors: Robertson R. Paul , Bogachus Lindsey D. , Oseid Elizabeth , Parazzoli Susan , Patti Mary Elizabeth , Rickels Michael R. , Schuetz Christian , Dunn Ty , Pruett Timothy , Balamurugan A.N. , Sutherland David E.R. , Beilman Gregory , Bellin Melena D.
Published: September 2014

We used intravenous arginine with measurements of insulin, C-peptide, and glucagon to examine β-cell and α-cell survival and function in a group of 10 chronic pancreatitis recipients 1–8 years after total pancreatectomy and autoislet transplantation. Insulin and C-peptide responses correlated robustly with the number of islets transplanted (correlation coefficients range 0.81–0.91; P < 0.01–0.001). Since a wide range of islets were transplanted, we normalized the insulin and C-peptide responses to the number of islets transplanted in each recipient for comparison with responses in normal subjects. No significant differences were observed in terms of magnitude and timing of hormone release in the two groups. Three recipients had a portion of the autoislets placed within their peritoneal cavities, which appeared to be functioning normally up to 7 years posttransplant. Glucagon responses to arginine were normally timed and normally suppressed by intravenous glucose infusion. These findings indicate that arginine stimulation testing may be a means of assessing the numbers of native islets available in autologous islet transplant candidates and is a means of following posttransplant α- and β-cell function and survival.