bluuebunny/crossref_metadata_2025 huggingface dataset:
Treating rhinophyma: A case report illustrating decortication/vaporization with an 808-nm diode laser
Authors: Gubitosi Adelmo , Ruggiero Roberto , Docimo Giovanni , Esposito Alessandro , Esposito Emanuela , Villaccio Giuseppe , Foroni Fabrizio , Agresti Massimo
Published: March 2012

Rhinophyma is a skin disease that is not only disfiguring but can also have a negative impact on respiratory function by causing nasal obstruction. There is a wide range of techniques used in the surgical management of rhinophyma, including laser treatment, all of which involve tissue ablation. With regard to the laser therapy, there is no consensus as to which laser is most effective. The authors present a case report to illustrate their method of treating rhinophyma with an 808-nm diode laser, which included the use of exogenous pigment to define the target area and the application of human fibrin glue to obtain good hemostasis and wound healing and prevent infection.
Triple-pass technique of pulsed dye laser in the treatment of port-wine stains
Authors: Aboelatta Yasser Abdallah
Published: March 2012

Pulsed dye laser (PDL) is considered the treatment of choice for port-wine stains (PWS). However, multiple laser sessions are required over a long period.

The aim of the study is to evaluate the ability of multiple passes of PDL to bring about faster PWS fading and reduce the treatment period.

Twenty patients with PWS were treated by triple passes of PDL with variable pulse durations (3, 6, and 10 ms). Each patient received three to six laser treatment sessions (spot size: 7 mm, fluencies: 8–12 J/cm

Minimal improvement occurred in only two patients.

Multiple passes of PDL did not result in faster fading of PWS lesions. The triple-pass technique may be of value if used in a different way or with different parameters.
“No-scar” surgery – A new field for lasers
Authors: Leonhard Martin
Published: March 2012

In the early days of abdominal surgery
Copolymerization of norbornene with styrene catalyzed by Ni{CF3C(O)CHC[N(naphthyl)]CH3}2/B(C6F5)3 and transparent films
Authors: Xing Yuepeng , Chen Yiwang , He Xiaohui
Published: March 2012

Copolymerization of norbornene (NB) with styrene (St) was carried out with the catalytic system of Ni{CF3C(O)CHC[N(naphthyl)]CH3}2 and B(C6F5)3 in toluene. The catalytic system exhibited higher activity 1.37×105(gpolymer/molNi·h) for copolymerization of NB and St. The influence of the comonomer feed content on the polymerization activity, as well as on the incorporation rates, was investigated. The St content in copolymers can be controlled to be 1.1–5.6 mol% at a content of 10–50 mol% of the St in the monomer feeds ratios. The reactivity ratios were determined to be rSt=0.453 and rNB=19.810 by the Kelen-TÜdÕs method catalyzed by the Ni{CF3C(O)CHC[N(naphthyl)]CH3}2/B(C6F5)3 system. The prepared copolymers had very high glass transition temperatures (Tg>320°C). Copolymers were processed by the solution casting method and the copolymer films showed good transparency in the visible region with 75–80% transmittance.
fMRI Repetition Suppression for Familiar But Not Arbitrary Actions with Tools
Authors: Valyear Kenneth F. , Gallivan Jason P. , McLean D. Adam , Culham Jody C.
Published: March 2012

For humans, daily life is characterized by routine interaction with many different tools for which corresponding actions are specified and performed according to well-learned procedures. The current study used functional MRI (fMRI) repetition suppression (RS) to identify brain areas underlying the transformation of visually defined tool properties to corresponding motor programs for conventional use. Before grasping and demonstrating how to use a specific tool, participants passively viewed either the same (repeated) tool or a different (non-repeated) tool. Repetition of tools led to reduced fMRI signals (RS) within a selective network of parietal and premotor areas. Comparison with newly learned, arbitrarily defined control actions revealed specificity of RS for tool use, thought to reflect differences in the extent of previous sensorimotor experience. The findings indicate that familiar tools are visually represented within the same sensorimotor areas underlying their dexterous use according to learned properties defined by previous experience. This interpretation resonates with the broader concept of affordance specification considered fundamental to action planning and execution whereby action-relevant object properties (affordances) are visually represented in sensorimotor areas. The current findings extend this view to reveal that affordance specification in humans includes learned object properties defined by previous sensorimotor experience. From an evolutionary perspective, the neural mechanisms identified in the current study offer clear survival advantage, providing fast efficient transformation of visual information to appropriate motor responses based on previous experience.
Regulation of GABA and Glutamate Release from Proopiomelanocortin Neuron Terminals in Intact Hypothalamic Networks
Authors: Dicken Matthew S. , Tooker Ryan E. , Hentges Shane T.
Published: March 2012

Hypothalamic proopiomelanocortin (POMC) neurons and their peptide products mediate important aspects of energy balance, analgesia, and reward. In addition to peptide products, there is evidence that POMC neurons can also express the amino acid transmitters GABA and glutamate, suggesting these neurons may acutely inhibit or activate downstream neurons. However, the release of amino acid transmitters from POMC neurons has not been thoroughly investigated in an intact system. In the present study, the light-activated cation channel channelrhodopsin-2 (ChR2) was used to selectively evoke transmitter release from POMC neurons. Whole-cell electrophysiologic recordings were made in brain slices taken from POMC-Cre transgenic mice that had been injected with a viral vector containing a floxed ChR2 sequence. Brief pulses of blue light depolarized POMC-ChR2 neurons and induced the release of GABA and glutamate onto unidentified neurons within the arcuate nucleus, as well as onto other POMC neurons. To determine whether the release of GABA and glutamate from POMC terminals can be readily modulated, opioid and GABABreceptor agonists were applied. Agonists for μ- and κ-, but not δ-opioid receptors inhibited transmitter release from POMC neurons, as did the GABABreceptor agonist baclofen. This regulation indicates that opioids and GABA released from POMC neurons may act at presynaptic receptors on POMC terminals in an autoregulatory manner to limit continued transmission. The results show that, in addition to the relatively slow and long-lasting actions of peptides, POMC neurons can rapidly affect the activity of downstream neurons via GABA and glutamate release.
Más allá del mito: mujeres, tequila y nación
Authors: Gaytán Marie Sarita , Zapata Ana G. Valenzuela
Published: March 2012

Junto con el mariachi y los charros, el tequila es uno de los íconos mexicanos más reconocidos en el mercado internacional. Sin embargo, en los dos primeros contamos con una presencia femenina indiscutible—mariachis con mujeres y escaramuzas. ¿Dónde están las mujeres del tequila? La presente investigación busca responder a esta pregunta al documentar la participación de mujeres en la cultura e industria del tequila, destacando sus contribuciones en relación a uno de los productos más importantes de México.
Ultraviolet Action Spectrum for Cell Killing of Primary Porcine Lens Epithelial Cells
Authors: Okuno Tsutomu , Nakanishi‐Ueda Takako , Ueda Toshihiko , Yasuhara Hajime , Koide Ryohei
Published: March 2012

Ultraviolet Action Spectrum for Cell Killing of Primary Porcine Lens Epithelial Cells: Tsutomu OKUNO, et al. Human Engineering and Risk Management Research Group, National Institute of Occupational Safety and Health, Japan—

Objectives

The aim of this study was to determine ultraviolet (UV) action spectra for cell killing of primary porcine lens epithelial cells (LECs) that can be used to establish guidelines for evaluation of the hazard of cataract due to UV exposure in the workplace.

Methods

Primary porcine LECs were exposed to different doses (radiant exposure) of UV at 17 different wavelengths from 235 nm to 311 nm. At 2 days after exposure, cell viability was assessed by measuring crystal violet staining of the cells and lactate dehydrogenase release into the culture medium. The exposure dose required to kill 50% of cells (LD50) was determined from the dose‐effect relationship obtained at each wavelength and was used to construct action spectra.

Results

The action spectra had a broad minimum in the approximate range of 250–280 nm, indicating that UV is most hazardous to porcine LECs within this wavelength range. The spectra rose steeply at both longer and shorter wavelengths. These action spectra are consistent with the in vivo action spectra for opacities in the rabbit lens and for light scattering in the rat lens, taking the transmittance of the ocular media into account.

Conclusions

These results will help to determine a UV hazard function for cataract formation, which can be used to draft guidelines for evaluation of the hazard of cataract due to UV exposure in the workplace.
Sintering and Dielectric Properties of SrTiO3-based Ceramics
Authors: Li Juan , Jin Dengren , Zhou Lixin , Cheng Jinrong
Published: March 2012

High dielectric tunability, low dielectric loss tangent and appropriate level of dielectric constant are the basic requirements for applications as electrically tunable dielectric microwave devices. In our experiments, the SrTiO3 green compacts made of the powder mixtures with various particle sizes were infiltrated with a BaTiO3 precursor solution and sintered at different temperatures between 1280 and 1350 ºC for 2 hours and 1350 ºC for 6 hours. The sintering, microstructural and dielectric properties were investigated. Results showed that the relative density of SrTiO3 ceramics could reached 93% when sintered at 1280 ºC for 2 hours. When sintered for 6 hours at 1350 °C, the room temperature dielectric constant of SrTiO3 reaches 900 at a frequency of 1MHz. It has only weak temperature dependence between 100 and 500K. The reason of the low sintering temperature for the dense SrTiO3 ceramics and the effects of sintering scheme on the dielectric properties from 100 K to 500 K are discussed in this paper.
Síndrome de desmielinização osmótica: relato de caso com evolução favorável
Authors: Jurno Mauro Eduardo , Castro Marina Horta Azevedo de , Lage Mariana de Assis , Dupin João Henrique , Paula Antonio José Fonseca de , Bello Gustavo de Vasconcelos
Published: March 2012

Os autores relatam um caso de paciente apresentando evolução favorável após confirmado diagnóstico de síndrome de desmielinização osmótica (mielinólise pontina central e extrapontina) através de exame de ressonância magnética.
The effect of a diet education with six iso-caloric meals on the body weight and blood glucose of diabetes type 2 patients
Authors: Salehi Musa , Yousefinejad Abbas , Pishdad Gholamreza
Published: March 2012

The treatment of Diabetes should not only be sought through drug administration; diet is also a part of its treatment. The aim of this study was to determine the effect of a diet with six meals having equal calories on the body weight and blood glucose on diabetes type 2 patients. This research is an Experimental study conducted in 2009 on 181 patients with diabetes. The patients visited the IDSF (Iranian Diabetes Society of Fars) weekly and the patients to be studied were randomly divided into two groups of 85 and 96 patients, respectively. The participants were repeatedly requested to consume their calculated calorie in six equal parts. The average age in the Experimental and Control groups were 51.2 ± 13.3 and 53.1 ± 9.4, respectively. The mean body weight and fasting blood glucose at the beginning of the study in Experimental and Control groups were 66.3 ± 9.4 and 69.1 ± 11.1 kg, 198.9 ± 35.1, and 199.8 ± 39.1 mg.dL-1, respectively. At the end of the study, however, the values were 63.5 ± 7.5 and 66.98 ± 9 kg, 139.5 ± 34.6 and 164.2 ± 22.1 mg.dL-1, respectively. Only the mean fasting blood glucose at the end of the study revealed a significant difference (p-value = 0.001). The results show that educating those afflicted with Diabetes Type 2 aiming at changing their diet can greatly help them manage their blood glucose.
Como você fez sua escolha?: o papel do foco motivacional sobre a tendência a inovar
Authors: Mantovani Danielle , Korelo Jose Carlos , Prado Paulo Henrique Muller
Published: March 2012

As intenções de adotar novos produtos são guiadas pelos sistemas de motivação nos sentidos de promoção de realizações (experiências positivas) e de prevenção de arrependimentos (experiência negativa). Este artigo supre uma lacuna teórica ao propor que tais sistemas motivacionais atuam por meio de um conjunto de objetivos de escolha, que, por sua vez, determinam a tendência do consumidor em inovar na categoria de produtos. A partir de entrevistas exploratórias e de um survey junto a consumidores que haviam adquirido produtos eletrônicos de uso pessoal recentemente, os autores examinam o problema como quatro objetivos de escolha. Destes, dois são de promoção (justificar e confiar na escolha) e dois de prevenção (evitar o arrependimento e avaliar os custos dessa mesma escolha), sendo que todos direcionam as tendências a adotar novos produtos. Conforme o grau de adoção de novas tecnologias, dois grupos de respondentes emergiram das análises. A comparação dos modelos dos grupos sugere que os respondentes com maior tendência a inovar demonstram maior confiança na escolha, maior capacidade de justificar a escolha, e também são mais capazes de evitar se arrepender. Tais resultados sugerem que os objetivos de escolha são antecedentes explicativos do comportamento de escolha e adoção de produtos inovadores.
Bem-estar no trabalho: um estudo sobre suas relações com clima social, coping e variáveis demográficas
Authors: Rocha Sobrinho Fábio , Porto Juliana Barreiros
Published: March 2012

O presente estudo teve como objetivo identificar o impacto de variáveis demográficas, do clima social e coping no bem-estar no trabalho. Para abordar bem-estar foi utilizado modelo que unifica as correntes eudaimônicas e hedonistas, e foram utilizadas as escalas de bem-estar no trabalho, compostas pelos fatores: realização no trabalho, afetos positivos e negativos; clima social. Esta, por sua vez, composta pelos aspectos: inovação e desempenho, reconhecimento e autonomia, adaptada para o contexto organizacional, validada no estudo e coping, composta pelos fatores: esquiva, manejo e controle. Participaram da pesquisa 2.438 funcionários de uma organização confessional do ramo de educação, que corresponde a 58% da população. As análises de correlação e regressão demonstraram que os fatores de clima impactam no bem-estar, dentre esses, autonomia apresentou correlação positiva e de moderada a alta com bem-estar, e os fatores inovação, desempenho e reconhecimento apresentaram correlações mais fortes. Nos fatores de coping, esquiva teve resultado fraco na correlação, porém, manejo e controle tiveram resultado significativo. Concluiu-se que o clima social e as estratégias de enfrentamento do estresse impactam no bem-estar no trabalho. Apesar das contribuições, foram limitações a coleta ter sido realizada pela própria organização, e o estudo se restringir a uma organização apenas.
Valor e vantagem competitiva: buscando definições, relações e repercussões
Authors: Ito Nobuiuki Costa , Hayashi Junior Paulo , Gimenez Fernando Antonio Prado , Fensterseifer Jaime Evaldo
Published: March 2012

O tópico central que motiva o presente trabalho é o papel que o valor desempenha nas teorias de estratégia e que, apesar de ser considerado nas principais correntes de pensamento do campo, ainda apresenta indefinição. O objetivo é explorar as principais definições de valor e suas implicações para o desenvolvimento teórico no campo da Administração Estratégica, mais especificamente, para as investigações sobre vantagem competitiva sustentável. Ao trabalhar com conceitos de valor, como valor de uso, valor de troca, criação de valor, valor capturado, valor percebido e uso do valor, pode-se demonstrar que a formação e a sustentação de vantagem competitiva estão além do olhar predominantemente econômico. Elas necessitam ser complementadas por dimensões que atinjam o consumidor, alterando seu estado de espírito, seus desejos e suas emoções. A vantagem competitiva, nesse novo contexto, pode ser entendida como uma governança de um sistema de firmas que se alinham para a criação e a entrega de um valor de uso, e que se relaciona mutuamente para dividir o valor. Em um movimento recursivo, as informações e valores seguem a montante e a jusante da cadeia de firmas, formando um fenômeno complexo em que o processo de formação da estratégia é determinado por uma heurística própria de cada estrategista.
Efeito da aplicação de maravilha (Mirabilis jalapa L.), primavera (Bougainvillea spectabilis L.) e isolados de Trichoderma na produção de alface
Authors: Azevedo Filho JA , Lucon CMM , Duarte LML , Chaves ALR , Donadelli A , Alexandre MAV , Kano C.
Published: March 2012

Objetivou-se com esse trabalho avaliar o efeito de extratos foliares de primavera (Bougainvillea spetabilis L.) e maravilha (Mirabilis jalapa L.) e de Trichoderma spp., isoladamente ou em combinação, no manejo de viroses e na produção de alface. Os ensaios foram conduzidos em área de produção de hortaliças folhosas no município de Pinhalzinho/SP. O delineamento experimental foi de blocos casualizados, com dez tratamentos comparados com controle químico convencional. Foram observadas reduções de 18% e 32% na população de bactérias da rizosfera nas plantas de alface tratadas com o isolado IB18/22 e extrato de primavera + isolados de Trichoderma spp., respectivamente. Verificou-se que o extrato de maravilha estimulou o aumento do número de UFC/g da população de fungos. Entretanto, não houve diferença significativa na massa fresca da parte aérea e, apesar da pressão de inóculo e da alta densidade populacional de insetos vetores de vírus no local, não foi constatada a ocorrência de viroses, com exceção do espessamento de nervuras, que ocorreu em menor número em plantas tratadas, comparadas as do controle. Economicamente, houve 27,8% de lucratividade e margem bruta de 38,5%, indicando a viabilidade do uso de ferramentas de base ecológica no cultivo de alface. Além disso, os produtos usados são de fácil aquisição, seguros em termos de aplicação, meio ambiente e para o consumidor.
Sobre cómo el conocimiento científico intenta aproximarse a la realidad
Authors: Solaz-Portolés Joan Josep
Published: March 2012

A partir de la creencia errónea de que el conocimiento científico ofrece un cuadro detallado del mundo en que vivimos y muestra los caminos para adentrarnos en él, en este trabajo se analizan las estructuras y los procesos de la ciência para permitir vislumbrar cómo se produce el acercamiento de la ciência a la realidad. En concreto, se examinan teorías, conceptos, modelos y explicaciones científicas desde bases epistemologicas que se fundamentan en la história de la ciência. Se concluye que las construcciones teoricas de los científicos, que siempre son provisionales, les permiten aproximarse al mundo real y avanzar en sus programas de investigación, pero son independientes de la realidad y no la copian
Perturbações cosmológicas e a taxa de crescimento das flutuações da matéria
Authors: Vom Marttens R.F. , Ribeiro F.K. , Zimdahl W.
Published: March 2012

As estruturas observadas no universo (galáxias, aglomerados e superaglomerados de galáxias) são resultados da instabilidade gravitacional. Esta instabilidade amplifica perturbações, originalmente muito pequenas, até o regime não linear. Neste artigo comparamos as taxas de crescimento das perturbacães da matéria para vários modelos cosmologicos. Geralmente, a presenca da energia escura diminui o crescimento. Os detalhes dependem das características do modelo, por exemplo do acoplamento com as perturbações da energia escura ou de uma interação no setor escuro do universo.
Morphology and morphometry of three Plasmodium juxtanucleare (Apicomplexa: Plasmodiidae) isolates
Authors: Elisei Carina , Fernandes Kátia, R. , Forlano Maria D. , Madureira Renata C. , Scofield Alessandra , Yotoko Karla S. C. , Soares Cleber O. , Araújo Flábio Ribeiro , Massard Carlos L.
Published: March 2012

In this work, three isolates of Plasmodium juxtanucleare have been analyzed based on morphological, morphometric and parasitic parameters. Each isolate was sampled from naturally infected adult chicken (Gallus gallus) from rural areas of three Brazilian municipalities: Seropédica (22º 48' S; 43º 41'W), in the state of Rio de Janeiro; Cruzeiro (22º 33' S; 44º 57'W), in the state of São Paulo; and Santa Bárbara do Tugúrio (21º 15' S; 43º 27' W), in the state of Minas Gerais. The blood samples taken from each infected chicken were inoculated in three groups of ten young chicken (21 days old). Blood smears of the experimentally infected chicken were sampled every two days until the 69th day in order to evaluate the parasitemia. For the morphological-descriptive and morphometric analyses, we measured 30 individuals from each of the intraerythocytic states, measures of the major (MD) and minor diameters (md), the estimation of morphometric index (Mi=md/MD) and size (T=pab, a= md/2; b=MD/2). The results indicated low and homogeneous parasitemia rates in the three strains, which showed differences among shape and size of the parasitic stadia displayed.
Infestação por Lynxacarus radovskyi (Tenorio, 1974) em gatos domésticos procedentes da região metropolitana do Recife, Pernambuco, Brasil
Authors: Romeiro Edenilze T. , Alves Leucio C. , Soares Ylka Maria V. , Matoso Ulysses N. V. , Faustino Maria Aparecida Da G.
Published: March 2012

Este estudo foi realizado com o objetivo de investigar a infestação por Lynxacarus radovskyi em gatos provenientes da Região Metropolitana de Recife, estado de Pernambuco, Brasil, durante o período de maio a dezembro de 2003. Foram coletadas amostras de pêlo de gatos de ambos os sexos e idades variadas, e submetidas a exame microscópico. Os resultados mostraram que 75,84% (254/335) dos animais estavam infestados com L radovskyi, não havendo, porém, diferença estatisticamente significativa entre a presença do ácaro e o sexo, a raça e a idade. Os resultados indicam que o ácaro L. radovskyi está disseminado na população felina estudada.
Desenvolvimento dos fungos Metarhizium anisopliae (Metschnikoff, 1879) Sorokin, 1883 E Beauveria bassiana (Balsamo) Vuillemin, 1912 sobre Ctenocephalides felis felis (Bouché, 1835)
Authors: Melo Denise R. De , Cruz Geraldo B. da , Reis Rosana C.S. , Bittencourt Vânia R.E.P.
Published: March 2012

A pulga Ctenocephalides felis felis é um parasita causador dermatites alérgicas e também pode transmitir diversos agentes etiológicos aos animais domésticos e aos homens. O objetivo deste trabalho foi verificar o desenvolvimento do fungo sobre a cutícula da pulga, através da microscopia eletrônica de varredura. Os isolados fúngicos testados foram o Metarhizium anisopliae 959 e Beauveria bassiana 986, ambos na concentração 10(8) conídios/ml. Após a exposição dos isolados fúngicos no período de duas, 15, 26 e 96 horas , o material foi processado para a microscopia eletrônica de varredura. Com a obtenção das micrografias, pode-se observar que com 2 horas após exposição aos fungos, os conídios estavam aderidos por toda a cutícula, situando-se preferencialmente nas membranas intersegmentais do abdome. Com 15 horas observou-se a formação do tubo de germinação e a cabeça do apressório e após 26 horas foi possível observar as ramificações e o engrossamento das hifas sobre a cutícula das pulgas. Os resultados indicam que os fungos testados foram capazes de se desenvolver sobre a cutícula de C. f. felis.
Measuring the Effects of Invasive Plants on Ecosystem Services: Challenges and Prospects
Authors: Eviner Valerie T. , Garbach Kelly , Baty Jill H. , Hoskinson Sarah A.
Published: March 2012

Plant invasions can have large effects on ecosystem services. Some plant invaders were introduced specifically to restore key services to ecosystems, and other invaders are having unintended, detrimental effects on services, such as the quantity and quality of water delivered, flood control, erosion control, and food production. Many ecosystem services are difficult to measure directly, and although there are extensive studies on plant invaders and ecosystem processes, a number of challenges prevent us from confidently extrapolating those processes as proxies for services. To extrapolate local, short-term measures of processes to ecosystem services, we must: (1) determine which processes are the key contributors to a service, (2) assess how multiple processes interact to provide a given service, (3) determine how vegetation types and species affect those processes, and (4) explicitly assess how ecosystem services and their controls vary over space and time, including reliance of ecosystem services on “hot spots” and “hot moments” and a minimum size of a vegetation type in the landscape. A given invader can have positive effects on some services and negative effects on others. It is important to consider that, in some systems, shifting environmental conditions may no longer support native species and that invasive species may be critical contributors to the resilience of ecosystem services.
Preparation of flat-polished specimens of slag-blended cement paste for backscattered electron imaging
Authors: Feng Shuxia , Wang Peiming , Liu Xianping
Published: March 2012

Scanning electron microscopy (SEM)-backscattered electron imaging and analysis (BSE-IA) is invaluable in blended cement research owing to its quantitative analysis qualities. For BSE-IA, flat-polished specimens without any artefacts are essential. However, preparation procedures of polished specimens are indefinite and are not stated in detail for cement paste, and no reports about it for slag-blended cement paste exist in published works. In this paper, excellent flat-polished specimens of slag-blended cement paste were prepared, and several factors influencing specimen quality were studied. Based on the authors' research, appropriate operations were suggested for the specimens to achieve high epoxy intrusion depth – that is, apply coarse emery papers for dry pre-grinding, let specimens stay under vacuum of 0·1 bar for at least 2 min before epoxy feeding, release the vacuum after epoxy feeding immediately. Moreover, it was found that increasing grinding force was effective in improving the planeness level of the polished surfaces, and 30 N was needed for slag-blended cement paste specimens to avoid obvious relief and altitude difference.
Effect of slab bottom reinforcement on seismic performance of post-tensioned flat plate frames
Authors: Han Sang Whan , Moon Ki Hoon , Park Young-Mi
Published: March 2012

The purpose of this study is to evaluate the seismic performance of gravity-designed post-tensioned flat plate frames with and without slab bottom reinforcement passing through the column. In low and moderate seismic regions, the seismic demands may not control the design, and buildings are often designed considering only gravity loads. This study focuses on the seismic performance of gravity load designed post-tensioned flat plate frames. For this purpose, three-, six- and nine-storey post-tensioned flat plate frames are designed considering only gravity loads. For reinforced concrete flat plate frames, continuous slab bottom reinforcement (integrity reinforcement) passing through the column should be placed to prevent progressive collapse; however, for the post-tensioned flat plate frames, the slab bottom reinforcement is often omitted since the requirement for the slab bottom reinforcement for post-tensioned flat plates is not clearly specified in ACI 318-05. This study evaluates the seismic performance of the model frames by conducting non-linear static pushover analyses and non-linear response history analyses. For conducting non-linear response history analyses, six sets of ground motions are used as input ground motions, which represent two different hazard levels (return periods of 475 and 2475 years) and three different locations (Boston, Seattle and Los Angeles). An analytical model is developed for emulating the non-linear hysteretic behaviour and the failure mechanism of post-tensioned slab–column connections. This study shows that gravity-designed post-tensioned flat plate frames have some seismic resistance. In addition, the seismic performance of post-tensioned flat plate frames is significantly improved by placing slab bottom reinforcement to pass through the column.
Effectiveness of CNI in slabs with a construction joint in a marine environment
Authors: Lopez-Calvo Herwing Z. , Montes-Garcia Pedro , Thomas Michael D. A. , Bremner Theodore W.
Published: March 2012

In marine concrete structures, construction joints, formed at the intersect of the end of one concrete placement and the beginning of a new placement, have been identified as vulnerable zones that may permit the intrusion of chlorides over a relatively small area of the reinforcement, thus accelerating corrosion. The present paper reports a research study to evaluate the effectiveness of calcium-nitrite corrosion inhibitor in combination with pulverised fly ash on the corrosion protection of reinforced concrete slabs manufactured with a construction joint intersecting the reinforcement at right angles and exposed to a marine environment for seven years. Electrochemical testing, chloride profiling using the scanning electron microscope/energy dispersive X-ray analyser and assessment of the damage caused by chloride-induced corrosion on the reinforcing bars, were conducted. Results showed that bars retrieved from low water/cementitious material ratio concretes containing calcium nitrite and fly ash experienced negligible corrosion damage; conversely, in specimens prepared with high water/cementitious material ratio, this combination provided a low level of protection.
Safety Testing of a New Electronic Toothbrush
Authors: Engel David , Nessly Michael , Morton Thomas , Martin Roy
Published: March 2012

While there have been major advances in understanding the causes and treatments of the inflammatory periodontal diseases in the past decade, there is still high reliance on the patient to prevent progression of disease through daily oral hygiene, primarily toothbrushing and flossing. A new electronic toothbrush, which produces mild fluid cavitation as well as rapid fluid streaming, has been developed and has shown promise in the ease and efficacy with which it removes plaque. In order to determine the safety of frequent and prolonged use of this device, the gingival tissues of 6 mongrel dogs were exposed to excessively long daily exposures to this toothbrush for up to 2 months. Each quadrant of each dog's mouth was randomly assigned a different treatment: no brushing, manual brush 1.0 minute, electronic brush 1.0 minute, or electronic brush 7.5 minutes. The dogs were examined weekly by a periodontist who was blinded to the treatments. Plaque scores and bleeding on probing scores were calculated, and possible gingival irritation was monitored carefully. At the end of the trial gingival biopsies taken from all the test areas. These were processed for conventional histopathologic evaluation and examined by an oral pathologist who was also blinded as to the treatments. The results showed that brushing a single posterior segment of teeth for 7.5 minutes daily for 2 months with the electronic brush did not result in any clinically or histologically evident damage to the gingiva. Rather, the areas so treated showed excellent health as determined by both clinical and histologic criteria. These findings support the contention that daily use of this electronic toothbrush is safe and effective in removal of dental plaque. J Periodontol 1993; 64:941–946.
Success and Failure Rates of Cylinder Implants in Type IV Bone
Authors: Fugazzotto Paul A. , Wheeler Stephen L. , Lindsay John A.
Published: March 2012

It is well documented that implant success rates are much lower in Type IV bone than in Types I, II, and III. However, all of these studies have reported on the use of screw type implants. The present study demonstrates the efficacy of cylinder implant use in Type IV bone. A total of 513 cylinders were placed in Type IV bone and were followed for 0 to 60+ months in function. The absolute success rate was 95.7%. Of the 22 fixture failures encountered, 8 were discovered at the time of second stage surgery, 3 during the first year following uncovering, and 11 occurred after 24 to 36 months in function. A possible rationale for the higher success rate of cylinders as compared to that reported for screw type implants in Type IV bone is presented. Further well‐controlled studies directly comparing various implant designs in a range of bony sites are needed to better understand and to fully document the differences suggested by the present study. J Periodontol 1993; 64:1085–1087.
The Management of Peri‐implant Breakdown Around Functioning Osseointegrated Dental Implants
Authors: Jovanovic Sascha A.
Published: March 2012

Peri‐implant tissue breakdown can be the result of microbial action as well as of biomechanical and occlusal overload. The long‐term goal of the treatment of peri‐implant breakdown is to arrest the progression of the disease and to achieve a maintainable site for the patient. Peri‐implant bony defects around functioning implants can be treated with either non‐surgical or surgical (resective or regenerative) techniques. Bone regeneration is possible in selected peri‐implant bony defects of functioning implants if appropriate surgical techniques are utilized and the etiologic cause is eradicated. J Periodontol 1993; 64:1176–1183.
The Distribution and Interrelationship of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, and BANA Scores Among Older Adults
Authors: Drake Claude W. , Hunt Ronald J. , Beck James D. , Zambon Joseph J.
Published: March 2012

In a random sample of subgingival dental plaque samples from 375 blacks and 300 whites aged 65 and older, immunofluorescence assays for 3 target pathogens including Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia, and BANA enzyme analysis were carried out. Blacks had significantly greater proportions of P. gingivalis and P. intermedia in their subgingival plaque and had significantly higher BANA scores. These assay results were investigated for concordance with each other and with 2 cariogenic salivary bacteria, Streptococcus mutans and lactobacilli. In general for both races, the periodontal pathogens were more likely to occur in combination with each other than with either S. mutans or lactobacilli. P. gingivalis and P. intermedia were more frequently associated with each other than with A. actinomycetemcomitans. There was a significant negative concordance between BANA and A. actinomycetemcomitans in whites and a significant positive concordance between BANA and P. intermedia in blacks. J Periodontol 1993; 64:89–94.
Periodontal Indices Around Natural and Titanium Abutments: A Longitudinal Multicenter Study
Authors: van Steenberghe Daniel , Klinge Björn , Lindén Ulf , Quirynen Marc , Herrmann Irene , Garpland Christina
Published: March 2012

This multicenter prospective study on the use of an implant system involved 9 centers and reports on the periodontal aspects after 3 years of observation. A total of 558 implants in 159 patients with 197 bridges all independent from natural teeth were originally included. Because of failures and patient withdrawals the number of implants was reduced to 460 and bridges to 174. The cumulative success rate for implants, starting from implant placement, is 94.3% after 2 years and 93.9% after 3 years indicating a leveling of implant loss. Failures concentrated in patients with a high plaque index. The loss of marginal bone was during the second and third years only 0.03 mm per year as an average while it was 0.4 mm during the first year. There were no reports of intense gingival inflammation in any of the patients and the plaque and gingivitis index behaved similarly around abutments and teeth. The probing pocket depth was significantly reduced over the observation time. The resistance towards marginal bone loss around these implants confirms the previous studies on fully edentulous patients. J Periodontol 1993; 64:538–541.
Short‐Term Sequential Administration of Amoxicillin/Clavulanate Potassium and Doxycycline in the Treatment of Recurrent/Progressive Periodontitis
Authors: Matisko Michael W. , Bissada Nabil F.
Published: March 2012

The systemic use of a single antibiotic was compared to that of a sequential antibiotic regimen in the treatment of A. actinomycetemcomitans and/or P. gingivalis‐associated periodontitis. Eleven patients with recurrent/progressive periodontitis and demonstrating subgingival infection with A.a. and/or P.g. were selected. Six patients received oral administration of doxycycline (Do), 200 mg the first day and 100 mg for 4 days thereafter, and then amoxicillin/clavulanate potassium (Au), 500 mg 3 times daily for 5 days. The other 5 patients received only doxycycline for 10 days. Eight sites with ≥5 mm probe depth per patient were selected, of which 4 received root planing at time 0. Clinical measurements (GI and PI, probing pocket depth, probing attachment level, and bleeding upon probing/suppuration) and microbial infection levels (2 sites/patient as per DNA probe) for A.a. and P.g. were recorded at 0, 4, 12, and 25 weeks. Clinical data were subjected to statistical analysis of variance and t‐tests for significance. The Do + Au groups produced significant reduction in probing pocket depth (PPD) at 4, 12, and 25 weeks (1.1, 1.3, and 1.1 mm, respectively). The Do group produced significant reduction in PPD only at 4 and 12 weeks (0.8 and 0.8 mm); the Do + Au group produced significant gain of 0.8 mm in probing attachment level at 4 and 12 weeks; and the Do + Au group in conjunction with root planing produced the most sustained reduction in PPD and gain in PAL. These findings suggest that the sequential use of multiple antibiotic agents may offer greater promise as an adjunctive treatment approach for the management of recurrent and/or progressive periodontitis than a single antibiotic regimen. J Periodontol 1993; 64:553–558.
Current Status of Systemic Antibiotic Usage in Destructive Periodontal Disease
Authors: Gordon Jeffrey M. , Walker Clay B.
Published: March 2012

The recognition that periodontal diseases are primarily caused by specific microorganisms has led researchers to explore the possibility that antibiotics may enhance the effect of mechanical debridement procedures such as scaling and surgery. For some selected periodontal diseases, this has proven to be true. This paper will review systemically‐administered antibiotics and the clinical studies and case reports supporting their use. In periodontal therapy, the tetracyclines are the most commonly‐used antibiotics in the United States. Tetracycline hydrochloride, minocycline, and doxycycline have been shown to inhibit in vitro most putative periodontal pathogens. Several studies support the use of tetracyclines in the treatment of localized juvenile periodontitis. Penicillins such as amoxicillin are effective in vitro against most periodontal pathogens but have limited efficacy due to the presence of beta‐lactamases in gingival fluid. Amoxicillin/ clavulanate potassium (Au) has proven effective in treating adult refractory periodontitis characterized by a Gram‐positive flora. Metronidazole is an effective adjunct in adult periodontitis associated with high numbers of “black‐pigmented Bacteroides” and spirochetes. A combination of metronidazole and amoxicillin produces a synergistic effect against A. actinomycetemcomitans and has been shown to be effective at eliminating this organism. Clindamycin is an effective adjunct in the treatment of adult refractory periodontitis associated with a predominantly Gram‐negative flora.

The use of macrolides, quinolones, and combinations of antibiotics is discussed. Clinical studies do not support the use of systemically‐administered antibiotics in routine adult periodontitis. Clinical studies do, however, support the use of antibiotics in the treatment of specific periodontal diseases. J Periodontol 1993; 64:760–771.
A Role for Antibiotics in the Treatment of Refractory Periodontitis
Authors: Walker Clay B. , Gordon Jeffrey M. , Magnussen Ingvar , Clark William B.
Published: March 2012

Refractory periodontitis is considered by many investigators to be a separate disease entity that is descriptive of a particular patient who has multiple sites, rather than a few individual sites, that do not respond to conventional periodontal treatment modalities. Such patients continue to demonstrate loss of attachment and alveolar bone despite frequent periodontal treatment which includes surgical intervention, scaling and root planing, and often systemically‐administered tetracycline. Controlled clinical studies have demonstrated that both clindamycin‐hydrochloride and amoxicillin/clavulanate potassium (Au) are beneficial when used in conjunction with periodontal scaling. Gordon et al. found improvements in attachment levels, inflammation, suppuration, and a decrease in pocket depths for up to 2 years following a 7‐day course of Clindamycin given in conjunction with a full‐mouth scaling. The incidence of disease activity decreased from an annual rate of 8% of all sites prior to antibiotic treatment to 0.5% after treatment. Magnusson, reporting on a similar group treated with a 14‐day course of Au, found an average loss of attachment of 2.2 mm and an increase in pocket depth of 1.5 mm in sites demonstrating disease progression prior to antibiotic treatment. At 3 months post‐antibiotic therapy, these sites had regained an average of 2 mm of attachment and pocket depths had decreased an equivalent amount. Both attachment levels and pocket depths remained relatively stable for up to 12 months post‐therapy. In an ongoing study, 30 subjects with refractory Periodontitis were treated with either Clindamycin or Au in conjunction with scaling or scaling plus a placebo. Prior to antibiotic treatment, but while being scaled at 3‐month intervals, sites with disease activity lost an average 2.4 mm of attachment. At 3 months post‐treatment, the clindamycin‐treated group showed an average gain of 2.1 mm, the Au‐treated group gained 1.9 mm, and the scaling group gained 1.4 mm in attachment. The clindamycin group remained relatively stable for up to 21 months and the Au group remained stable for about 15 months without additional treatment. Five of the 6 subjects treated with scaling alone required additional treatment within 9 months. Preliminary analyses have indicated that at least two patterns or rates of attachment loss may be associated with refractory periodontitis and that each pattern may be indicative of a different microflora. The pattern associated with a relatively rapid loss of attachment was characterized by a Gram‐negative flora which contained spirochetes, P. intermedia, and Fusobacterium species. A slow, continuous rate was associated with a predominantly Gram‐positive flora containing a high proportion of S. intermedius and/or a S. intermedius‐like organism. J Periodontol 1993; 64:772–781.
Erythema Multiforme Involving Gingiva
Authors: Barrett Andrew W. , Scully Crispian M. , Eveson John W.
Published: March 2012

Erythema multiforme is a vesiculobullous condition that may affect skin and/or mucosa. Oral lesions are characterized by hemorrhagic crusting of the lips and ulceration mainly of the non‐keratinized mucosa. This paper describes a patient who presented with gingival lesions as well as the more typical oral signs of erythema multiforme. J Periodontol 1993; 64:910–913.
The double tragedy of irrigation systems in Tamil Nadu, India: assessment of the replacement of traditional systems by private wells
Authors: Kajisa Kei
Published: March 2012

This paper investigates the impact of the replacement of traditional communal irrigation systems called tanks by modern irrigation systems, that is, private wells with pumps, using a village and household data set collected in Tamil Nadu, India. Our statistical analyses find that, once the tanks deteriorate, the rice yield of farmers who have no access to wells and thus rely solely on traditional irrigation systems will decrease, whereas those of farmers with well access will not be affected. Since compensation for yield loss by income diversification is difficult, the reduction of income is so large that poverty among farmers without well access increases. Our analyses also find that, even among farmers with well access, the dissemination of private wells results in no significant increase in net return or profit of rice cultivation, presumably because the overexploitation of groundwater increases the cost of irrigation and cancels out the well users' high revenue from high yield. In this way, the replacement process creates a double tragedy: increased poverty among farmers without well access and overexploitation and profit reduction among farmers with well access. Policy options to avoid the tragedy are discussed in the concluding section.
Evaluation of Chemical Treatment on Zirconia Surface with Two Primer Agents and an Alkaline Solution on Bond Strength
Authors: Lorenzoni FC , Leme VP , Santos LA , de Oliveira PCG , Martins LM , Bonfante G
Published: March 2012

Objectives

This study evaluated the effect of an alkaline solution and two 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-based primer agents on bond strength to zirconia (yttria-stabilized tetragonal zirconium polycrystal [Y-TZP]) through the shear bond strength (SBS) test.

Materials and Methods

Sixty square-shaped Y-TZP samples were embedded in an acrylic resin mold, polished, and randomly assigned to one of six groups (n=10) according to treatment surface: group CR, no treatment (control); group NaOH, 0.5 M NaOH; group AP, Alloy Primer; group ZP, Z-Primer Plus; group NaOH-AP, 0.5 M NaOH + Alloy Primer; and group NaOH-ZP, 0.5 M NaOH + Z-Primer Plus. The resin cement (Rely X U100) was applied inside a matrix directly onto the Y-TZP surface, and it was light-cured for 40 seconds. The samples were stored in distilled water at 37°C for 24 hours prior to the test, which was performed in a universal machine at a crosshead-speed of 0.5 mm/min. The data were analyzed by one-way analysis of variance and Tukey tests (p<0.05). Light stereomicroscopy and scanning electron microscopy were used to assess the surface topography and failure mode.

Results

The SBS was significantly affected by the chemical treatment (p<0.0001). The AP group displayed the best results, and the use of NaOH did not improve SBS results relative to either AP or ZP. The samples treated with Alloy Primer displayed mainly mixed failures, whereas those conditioned with Z-Primer Plus or with 0.5 M NaOH presented a balanced distribution of adhesive and mixed failure modes.

Conclusions

The use of a NaOH solution may have modified the reactivity of the Y-TZP surface, whereas the employment of a MDP/6-4-vinylbenzyl-n-propyl amino-1,3,5-triazine-2,4-dithione–based primer enhanced the Y-TZP bond strength.
Weak Versions of Stochastic Adams-Bashforth and Semi-implicit Leapfrog Schemes for SDEs
Authors: Ewald Brian
Published: March 2012

We consider the weak analogues of certain strong stochastic
numerical schemes, namely an Adams-Bashforth scheme and a semi-implicit leapfrog scheme. We show
that the weak version of the Adams-Bashforth scheme converges weakly
with order 2, and the weak version of the semi-implicit leapfrog
scheme converges weakly with order 1. We also note that the weak
schemes are computationally simpler and easier to implement than the
corresponding strong schemes, resulting in savings in both
programming and computational effort.