bluuebunny/crossref_metadata_2025 huggingface dataset:
Activity patterns of South American silver catfish (Rhamdia quelen)
Authors: Schulz U. H. , Leuchtenberger C.
Published: August 2006

The South American silver catfish (Rhamdia quelen) is a widely distributed species in Central and South America in areas east of the Andes between Venezuela and the northern parts of Argentina. The bottom dwelling species occurs in lakes and reservoirs as well as in rivers. Between June 2000 and December 2001, sixteen silver catfish were tracked during fourteen 24-h cycles in two-hour-intervals, with the aim of investigating daily movements and habitat use. Covered distances varied between 0 m/2 h and 326 m/2 h and the mean distance covered in 2 h was 25.6 m. The mean activity of individual silver catfish varied between 5.6 m/2 h and 81.4 m/2 h. The swimming activity was linearly related to the total fish length. The highest mean swimming activity occurred in the morning and at nightfall. Silver catfish concentrated in three areas of frequent use. All of them were characterized by steep banks providing shelter in the form of rip-rap or large woody debris. Vertically, silver catfish preferred the upper 2 m layer where tracked fish encountered higher temperatures and higher dissolved oxygen concentrations.
Soil characteristics of a hyperseasonal cerrado compared to a seasonal cerrado and a floodplain grassland: implications for plant community structure
Authors: Amorim P. K. , Batalha M. A.
Published: August 2006

Savannas may be divided according to their seasonality into semi-seasonal, seasonal, hyperseasonal, or marshy savannas. Hyperseasonal savannas are characterized by the alternation of two contrasting stresses during each annual cycle, one induced by drought and fire and the other, by waterlogging. In South America, the largest savanna region is the Brazilian cerrado, in which there are few hyperseasonal areas that become waterlogged in the rainy season. The cerrado soils are generally well drained, but in central Brazil there is a small cerrado area in which the soil is poorly drained and which becomes waterlogged in the middle of the rainy season, allowing the appearance of a hyperseasonal cerrado. As long as soil is important in the ecology of the cerrado vegetation, we asked whether the waterlogging in this hyperseasonal cerrado implied that there were differences in soil characteristics in relation to a seasonal cerrado, which is not waterlogged in the rainy season, and to a floodplain grassland, which remains waterlogged throughout the year. In each environment, we randomly selected ten points, in which we collected soil samples in the mid-rainy season for chemical and granulometric analyses. For all variables, we found significant differences among the three environments, at least at one of the depths. Nevertheless, when we took into account all the variables together, we observed that the soils under the hyperseasonal and seasonal cerrados were similar and both were different to the soil under the floodplain grassland. The soil under the floodplain grassland was related to larger amounts of clay, silt, organic matter, phosphorus, aluminium, aluminium saturation, cation exchange capacity, and sum of bases, whereas soils under hyperseasonal and seasonal cerrados were related to higher pH values, base saturation, calcium, magnesium, and sand. As long as the soil under both cerrados was chemically and physically similar, the duration of waterlogging in the hyperseasonal cerrado is not long enough to alter its soil characteristics. Limitations to the plants growing on the hyperseasonal cerrado soil must be a consequence of the direct effects of flooding. Since cerrado plant species are dryland ones, the hypoxia caused by waterlogging may limit the number of cerrado species able to withstand these conditions.
Aspectos comparativos das comunidades de aranhas (Araneae) em dois remanescentes de Mata Atlântica do Estado da Bahia, Brasil
Authors: Benati Kátia Regina , Souza-Alves João Pedro , Silva Elizabete Alves , Peres Marcelo Cesar Lima , Coutinho Érica Oliveira
Published: August 2006

A Mata Atlântica vem sofrendo um acelerado processo de fragmentação, o que está afetando sua biodiversidade. O objetivo do trabalho foi inventariar as comunidades de aranhas em dois remanescentes de Mata Atlântica do Estado da Bahia, permitindo uma comparação entre a abundância, riqueza e diversidade de espécies entre estas áreas, visando fornecer subsídios para estudos da dinâmica de fragmentos florestais. Foram amostrados remanescentes com tamanhos bastante distintos, o Parque Metropolitano de Pituaçu - Salvador (PMP) com 425 ha e o Parque Municipal da Matinha - Itapetinga (PMM) com nove ha. As aranhas foram capturadas por coleta manual noturna, num transecto de trinta por cinco metros durante uma hora, com esforço total de 10h. Foi coletado um total de 362 indivíduos, distribuídos em 20 famílias, com 152 adultos e 60 espécies, sendo 37 spp. e 12 famílias no PMP e 30 spp. e 16 famílias no PMM. Ao comparar a abundância das famílias mais freqüentes (mínimo de dez capturas) não houve diferenças significativas entre as áreas (U=46,00; p=0,7959), com um índice de similaridade de Sorensen de 82,4%. Quando comparada a riqueza estimada e a abundância de espécies, não houve diferenças significativas entre as duas áreas (U=65.000; p=0,2799) e (U=20755, p=0,1451), respectivamente. Já a diversidade encontrada nas duas áreas, foi maior no PMP (D=8,1922) do que no PMM (D=6,8032). A partir dos resultados, sugere-se que as semelhanças encontradas entre as áreas podem estar relacionadas a fatores ligados aos processos da fragmentação, como histórico de perturbações. Contudo, sugerimos que seja feita uma avaliação a posteriori de outros fatores, como a forma do fragmento, o tipo de vizinhança e efeito de borda, além de outras variáveis, i.e. da composição florística, que possam estar interferindo na dinâmica destes fragmentos e influenciando na comunidade destas aranhas.
Comunidade de aranhas (Arachnida, Araneae) do pantanal norte (Mato Grosso, Brasil) e sua similaridade com a araneofauna amazônica
Authors: Raizer Josué , Japyassú Hilton F. , Indicatti Rafael P. , Brescovit Antonio D.
Published: August 2006

As aranhas são excelentes objetos de estudo para a avaliação da organização das comunidades animais e da influência do hábitat sobre estas comunidades. Contudo, para o entendimento da organização de uma dada comunidade é preciso o registro dos seus componentes (espécies). Para tanto, foi feito um levantamento das espécies de aranhas na região das cabeceiras da Bacia do Rio Paraguai. Foram realizadas coletas sistemáticas (guarda-chuva entomológico e transecto noturno) e ocasionais. Este esforço de coleta permitiu a descoberta de pelo menos 16 novas espécies, além do registro de 39 novas ocorrências de espécies para o estado do Mato Grosso. Foram coletadas 2114 aranhas (601 adultas), agrupadas em 206 morfoespécies de 35 famílias (sete apenas com indivíduos imaturos) e 105 gêneros, sendo que as estimativas estatísticas apontam para a existência de 290 espécies na área. As famílias mais ricas em espécies foram Araneidae (51 espécies), Theridiidae (46 spp.) e Salticidae (36 spp.), que representam juntas mais de 65% das espécies registradas. A estrutura da comunidade apresenta alto número de espécies e baixo número de indivíduos por espécie, o que é característico de comunidades tropicais de aranhas. Comparando-se a distribuição das espécies no pantanal e na Amazônia Legal, vê-se que a influência amazônica existe já em localidades mais ao sul, como Cáceres (47% fauna amazônica), aumentando progressivamente à medida que se prossegue para o norte (Indiavaí - 75%; Reserva do Cabaçal - 82%; Jauru - 86%).
Uma nova espécie de Tityus C. L. Koch, 1836 (Scorpiones, Buthidae) do estado da Bahia, Brasil
Authors: Candido Denise Maria , Lucas Sylvia , Souza Cláudio Augusto Ribeiro de , Diaz Diego , Lira-da-Silva Rejâne Maria
Published: August 2006

Uma nova espécie do gênero Tityus C.L. Koch, 1836 (Scorpiones, Buthidae) é descrita dos municípios de Anagé (36'44''14S - 08'08''41W) e Poções (31'47''14S - 21'55''40W) no estado da Bahia, Brasil. Tityus aba n. sp pertence ao grupo Tityusbahiensis (Lourenço, 2002), caracterizado por espécies de tamanho que variam de cinco a sete cm de comprimento, com colorido variando do amarelo - palha ao marrom avermelhado e sem a lâmina mediana basal dilatada nas fêmeas. Neste grupo, aproxima-se das espécies do complexo Tityusstigmurus (Lourenço, 2001). A nova espécie é mais próxima de Tityus stigmurus (Thorell, 1876), Tityus martinpaechi Lourenço, 2001 e de Tityus melici Lourenço, 2003, distinguindo-se da primeira por apresentar o prossoma quase totalmente negro, maior número de dentes pectíneos e tamanho maior; da segunda por não apresentar manchas nos palpos e pernas, ausência de uma mancha negra de forma triangular sobre o prossoma e também tamanho maior, a da última pela ausência de manchas confluentes no mesossoma e de faixa longitudinal na face ventral dos segmentos de I a IV do metassoma. Tityus aba n.sp. apresenta indivíduos de médio a grande porte, medindo de 6,0 a 7,65 centímetros, de colorido geral castanho claro, com prossoma escuro quase negro e tergitos com três faixas escuras longitudinais, sendo uma mediana e duas laterais; carenas medianas dorsais dos segmentos II a IV com o último granulo maior, tornando-se espiniforme nos segmentos III e IV. Os machos apresentam os palpos mais delgados em relação às fêmeas e os segmentos IV e V do metassoma mais dilatados.
Reproductive activity and vocalizations of Leptodactylus labyrinthicus (Anura: Leptodactylidae) in southeastern Brazil
Authors: Zina Juliana , Haddad Célio F. B.
Published: August 2006

Vocalizations and reproductive activity of two Leptodactylus labyrinthicus populations were studied from Jun/2001 to Feb/2003 in the State of São Paulo, Brazil. Observations began at dusk and ended around 2300 h. Occasionally individuals were monitored throughout the night. Data on reproductive period, calling sites, adult snout-vent length (SVL), oviposition sites, and oviposition period was collected. Leptodactylus labyrinthicus had an extended breeding period associated mainly with rainfall. Males called from the edge of temporary or permanent ponds, began vocalization activity at dusk, and finished around 2300 or 2400h. During the peak of the vocalization period (Dec- Jan), calling activity could extend up to 0400 or 0500h. Three types of vocalizations associated with reproduction were recorded: advertisement call, territorial call, and courtship call. The advertisement call was the most common vocalization. Males and females showed no sexual dimorphism in SVL. However, the males of one population were significantly larger than those of the other population studied. This fact could be explained by frog-hunting in one of the areas, which could wipe out the larger males of the population. Foam nests were recorded mainly in Oct-Nov 2001/2002 in depressions at the edge of temporary ponds, always protected by vegetation. A mean of 6.5% of the eggs present in the foam were fertilized and the other 93.5% possibly are used as a food source by the tadpoles. Mean diameter of the foam nest was 25.4 cm and mean height was 11.4 cm.
Habitat use by two species of Hypostomus (Pisces, Loricariidae) in southeastern brazilian streams
Authors: Casatti Lilian , Rocha Fabíola C. , Pereira Danusa C.
Published: August 2006

In this study, habitat use of the armored catfishes Hypostomus ancistroides and Hypostomus sp. was investigated in 21 streams from the Upper Rio Paraná system in São Paulo State, Brazil, a pasture dominated region. The abundance of Hypostomus sp. was positively correlated with the amount of riffles and riparian vegetation condition, whereas H. ancistroides abundance was negatively correlated with riparian vegetation condition. Thirteen ecomorphological attributes analyzed by principal component analysis showed that when compared to H. ancistroides, Hypostomus sp. presented a wider mouth and more flattened body, suggesting an adapted body to faster waters. The most abundant populations of Hypostomus sp. were predominantly associated with good riffle availability and good riparian quality, suggesting that populational features of this species may be incorporated in the stream biotic integrity assessment in that region.
Effect of fluoridated varnish and silver diamine fluoride solution on enamel demineralization: pH-cycling study
Authors: Delbem Alberto Carlos Botazzo , Bergamaschi Maurício , Sassaki Kikue Takebayashi , Cunha Robson Frederico
Published: August 2006

OBJECTIVE: In the present investigation, the anticariogenic effect of fluoride released by two products commonly applied in infants was evaluated. METHODS: Bovine sound enamel blocks were randomly allocated to each one of the treatment groups: control (C), varnish (V) and diamine silver fluoride solution (D). The blocks were submitted to pH cycles in an oven at 37ºC. Next, surface and cross-sectional microhardness were assessed to calculate the percentage loss of surface microhardness (%SML) and the mineral loss (deltaZ). The fluoride present in enamel was also determined. RESULTS: F/Px10-3 (ANOVA, p<0.05) in the 1st layer of enamel before pH-cycling were (C, V and D): 1.61ª; 21.59b and 3.98c. The %SMH (Kruskal-Wallis, p<0.05) were: -64.0ª, -45.2b and -53.1c. %deltaZ values (ANOVA, p<0.05) were: -18.7ª, -7.7b and -17.3ª. CONCLUSION: The data suggested that the fluoride released by varnish showed greater interaction with sound enamel and provided less mineral loss when compared with silver diamine solution.
Fiber-reinforced fixed partial dentures: a preliminary retrospective clinical study
Authors: Piovesan Edno Moacir , Demarco Flávio Fernando , Piva Evandro
Published: August 2006

The aim of this study was to evaluate the clinical performance (retention rate) of fiber-reinforced composite fixed partial dentures (FPDs). Polyethylene fiber (Ribbond®) was used combined with restorative composite during FPDs fabrication. FPDs were placed in thirteen patients in a private clinic. Nineteen FPDs were evaluated. The prosthetic space was filled with only one pontic using extracted teeth (2 cases), acrylic resin teeth (11 cases), or with composite resin (6 cases), combined with Polyethylene fiber. The clinical criterion used was based on retention rate of FPDs. If FPDs were in function in the mouth at the time of examination without previous repair they were classified as Complete Survival (CS) restorations. A classification of Survival with Rebonding (SR) was assigned in the event of an adhesive failure, but after rebonding the FPD still remained under evaluation. Treatment was classified as a Failure (F) if the FPD restoration was lost. The time of evaluation was 41.15 months (±15.13). The FPDs evaluated were retained (CS=94.75%), and no failure was found except for in one situation which required rebonding (SR=5.25%). According to the survival estimation method of Kaplan-Meyer the mean survival time was 42.3 months. At the time of evaluation investigated, polyethylene-reinforced FPDs showed a favorable retention rate in preliminary data.
TENS and low-level laser therapy in the management of temporomandibular disorders
Authors: Kato Melissa Thiemi , Kogawa Evelyn Mikaela , Santos Carlos Neanes , Conti Paulo César Rodrigues
Published: August 2006

Pain relief and reestablishment of normal jaw function are the main goals of conservative management of Temporomandibular Disorders (TMD). Transcutaneous electrical nerve stimulation (TENS) and laser therapy are part of these modalities, although little is known about their real efficacy in controlled studies. This research compared these two treatments in a sample of 18 patients with chronic TMD of muscular origin, divided into two groups (LASER and TENS). Treatment consisted of ten sessions, in a period of 30 days. Active range of motion (AROM), visual analogue scale (VAS) of pain and muscle (masseter and anterior temporalis) palpation were used for follow-up analysis. Data were analyzed by Friedman test and ANOVA for repeated measurements. Results showed decrease in pain and increase in AROM for both groups (p<0.05), and improvement in muscle tenderness for the LASER group. Authors concluded that both therapies are effective as part of TMD management and a cumulative effect may be responsible for the improvement. Caution is suggested when analyzing these results because of the self-limiting feature of musculoskeletal conditions like TMD.
Avaliação da capacidade de exercício em portadores de doença pulmonar obstrutiva crônica: comparação do teste de caminhada com carga progressiva com o teste de caminhada com acompanhamento
Authors: Rosa Fernanda Warken , Camelier Aquiles , Mayer Anamaria , Jardim José Roberto
Published: August 2006

OBJETIVO: Avaliar a aplicabilidade do teste de caminhada com carga progressiva em portadores de doença pulmonar obstrutiva crônica, e comparar o desempenho desses pacientes durante esse teste e o de caminhada de seis minutos com acompanhamento. MÉTODOS: Foi realizado um estudo de corte descritivo, em que foram selecionados 24 portadores de doença pulmonar obstrutiva crônica. Em ordem aleatória, realizou-se um teste de caminhada com carga progressiva e um de caminhada de seis minutos com acompanhamento, após um período de prática inicial. RESULTADOS: Os pacientes alcançaram no teste de caminhada com carga progressiva, em média, uma freqüência cardíaca máxima de 76,4 ± 9,7%, valor inferior aos 84,1 ± 11,4% alcançados no de caminhada de seis minutos com acompanhamento, em relação ao máximo previsto para idade e gênero (p = 0,003). A sensação de dispnéia ao final do teste (escala de Borg) também foi maior no de caminhada de seis minutos com acompanhamento. Os pacientes caminharam, em média, 307,0 ± 89,3 metros no teste de caminhada com carga progressiva, contra 515,5 ± 102, 3 metros no de caminhada de seis minutos com acompanhamento (p < 0,001). Houve boa correlação entre as distâncias percorridas entre os dois testes (r = 0,80, p < 0,001). CONCLUSÃO: O teste de caminhada com carga progressiva é simples e fácil de ser realizado em portadores de doença pulmonar obstrutiva crônica. O teste de caminhada de seis minutos com acompanhamento levou a uma maior freqüência cardíaca e a maior sensação de dispnéia ao seu final.
Effects of a glass-ionomer cement on the remineralization of occlusal caries: an in situ study
Authors: Amaral Mônica Tostes , Guedes-Pinto Antônio Carlos , Chevitarese Orlando
Published: August 2006

This work evaluated the remineralization of demineralized enamel of pits and fissures of human third molars sealed with a glass ionomer cement (Fuji IX, GC Corporation - Japan) or with a Bis-GMA sealant (Delton - Dentsply). Ten volunteers participated in this in situ study that consisted of two thirty-day periods using intra-oral devices, with a week’s interval in between. Four experimental treatment procedures and one control were randomly assigned to the volunteers’ specimens: Group I, no treatment, control; Group II, artificial caries process; Group III, same treatment as Group II, but sealed with Delton (Dentsply); Group IV, same treatment as Group II, but sealed with Fuji IX (GC Corporation - Japan); Group V, same treatment as Group II and no sealing. Groups I and II were not submitted to the oral environment and served as controls. After a period of 30 days in the oral environment, the specimens were removed from the devices, embedded in acrylic resin, ground flat and polished. Then, Knoop hardness tests were performed, with a 25 g static load applied for 15 seconds. The measurements were made from the base of the fissure up to an opening of 600 µm, pre-established between the inclines of the cusps. Three indentations were then made, located at 25, 75, and 125 µm in depth from the outer enamel margin and 100 µm apart from each other (Micromet 2003). The Brieger F and Bonferroni’s tests were applied to the measurements. It was concluded that sealing with the glass ionomer cement Fuji IX was capable of making the enamel of pits and fissures more resistant by increasing the value of Knoop hardness.
Cytologic alterations in the oral mucosa after chronic exposure to ethanol
Authors: Reis Sílvia Regina de Almeida , Espírito Santo Alexandre Ribeiro do , Andrade Miguel Gustavo Setúbal , Sadigursky Moysés
Published: August 2006

The effects of ethanol alone on the oral mucosa are still poorly understood, especially because there are few non-smoking chronic consumers of alcoholic beverages. The aim of this study was to evaluate the frequency of micronucleus, abnormal nucleus/cytoplasm ratio, pyknosis, karyorrhexis and karyolysis in exfoliated cells from the buccal mucosa and from the lateral border of the tongue in 36 non-smoker alcoholics (ethanol group) and 18 non-smokers and non-drinkers (control group). The Papanicolaou method was used. Since alcoholics generally have hepatobiliary involvement, the association between serum gamma-glutamyl transpeptidase (GGT) and some of the analyzed oral mucosa alterations was also investigated. The ethanol group showed a significant increase in the frequency of all alterations analyzed in the tongue cells when compared with the control group (p < 0.01; Mann-Whitney). However, the presence of these changes in buccal mucosa cells was not statistically significant (p > 0.05; Mann-Whitney). In the ethanol group, the correlation between serum GGT and the frequency of micronucleus and abnormal nucleus/cytoplasm ratio in oral mucosa cells was not significant (p > 0.05; Spearman). In conclusion, chronic exposure to ethanol may be associated with carcinogenic cytologic changes in the oral mucosa, even in the absence of tobacco smoking. These alterations were not correlated with hepatobiliary injury.
Activity, distribution and regulation of phosphofructokinase in salivary gland of rats with streptozotocin-induced diabetes
Authors: Nicolau José , Souza Douglas Nesadal , Nogueira Fernando Neves
Published: August 2006

Although the influence of diabetes on salivary glands is well studied, it still presents conflicting results. In this work, the regulation of the phosphofructokinase-1 enzyme (PFK-1) was studied utilizing the salivary glands of rats. Diabetes was induced by a single intraperitoneal injection of streptozotocin (60 mg/Kg of body weight) in rats (180-200 g). The animals were killed 30 days after the induction of diabetes and the submandibular and parotid salivary glands were used. Hyperglycemia was evaluated by blood sugar determination. The distribution of PFK-1 between the soluble and cytoskeleton fractions, the phosphate content of PFK-1, the content of fructose-2,6-bisphosphate and the activity of the PFK-2 enzyme were determined. The calculated relative glandular weight showed a higher value for the parotid gland in comparison with the control, but not for the submandibular gland. The activity of PFK-1 expressed per gland showed no variation between diabetic and control animals. However, considering the specific activity, the soluble enzyme presented a value 50% higher than that of the control and the cytoskeleton bound form increased by 84% compared to the control. For the parotid gland, no difference in the specific activity between diabetic and control animals was observed. On the other hand, the activity per gland of the soluble enzyme increased in the diabetic animals. The phosphate content of PFK-1 increased in the submandibular and parotid glands of diabetic rats. Both the content of fructose-2,6-bisphosphate and the active form of PFK-2 were reduced in the diabetic glands. In conclusion, the increase in the activity of PFK-1 observed in the salivary glands of rats with streptozotocin-induced diabetes does not seem to be due to its modulator fructose-2,6-bisphosphate.
Evaluation of the antimicrobial activity of each component in Grossman’s sealer
Authors: Savioli Ricardo Novak , Pecora Jesus Djalma , Mian Henis , Ito Izabel Yoko
Published: August 2006

The antimicrobial activity of Grossman’s sealer and its components was evaluated on 13 different strains using the double layer well-diffusion method. Results revealed that Grossman’s sealer presented antimicrobial activity against all the tested strains. Among the components of the cement, sodium tetraborate presented the greatest antimicrobial activity, both in type and diameter of the halo and ring of inhibition. Sealer powder, rosin, and eugenol presented similar activity, with no effect on P. aeruginosa and C. albicans. Among these, only eugenol had an effect on E. coli. Zinc oxide was only active against S. sobrinus and E. coli. Barium sulfate and bismuth subcarbonate did not show any antimicrobial effect.
Efficacy of a herbal toothpaste on patients with established gingivitis: a randomized controlled trial
Authors: Ozaki Fabiana , Pannuti Claudio Mendes , Imbronito Ana Vitória , Pessotti Wellington , Saraiva Luciana , Freitas Nívea Maria de , Ferrari Graziella , Cabral Veronica Neto
Published: August 2006

The aim of this randomised, double blind controlled trial was to verify the efficacy of a herbal dentifrice on the reduction of plaque and gingivitis. Forty eight volunteers with established gingivitis were randomly assigned to either a test group (herbal dentifrice) or positive control group (dentifrice with triclosan and fluoride). The dentifrices were distributed in plain white tubes by an independent pharmacy, which revealed the contents of each tube only after the experimental period. Plaque and gingivitis assessments were carried out on baseline and after 28 days of product use. All examinations were conducted by the same calibrated investigator. Subjects were instructed to brush their teeth three times daily using their assigned dentifrice for 28 days. There was a significant reduction in plaque levels in both the test and control groups. However, there was no significant difference between the groups. A significant reduction in gingivitis was observed in both groups, although there was no significant difference between them. No adverse reactions were reported. The authors concluded that both dentifrices were effective in reducing plaque and gingivitis in subjects with established gingivitis.
Herbicide dynamics in the Bogue Phalia watershed in the Yazoo River basin of Mississippi
Authors: Shaw David R. , Schraer Stephen M. , Prince Joby , Boyette Michele
Published: August 2006

A two-year surface water reconnaissance of the Bogue Phalia and its tributaries was conducted in 1997 and 1998. Cyanazine and metolachlor in surface water samples were quantified using enzyme-linked immunosorbent assays (ELISA). Cyanazine and metolachlor were detected in 101 and 132 of 160 samples, respectively. Cyanazine concentrations ranged from 0.1 to 2.2 g L−1and exceeded the U.S. Environmental Protection Agency (EPA) lifetime health advisory level (HAL) of 1 g L−1in eight samples. However, concentrations never exceeded the HAL for shorter exposure times. Metolachlor concentrations never reached the lifetime HAL of 100 g L−1. Metolachlor concentrations ranged from 0.1 to 20.6 g L−1. Metolachlor was detected more frequently and found to be more persistent throughout the growing season than was cyanazine. Higher cyanazine and metolachlor concentrations were detected at sampling dates that coincided with herbicide applications. One of the Bogue Phalia's tributaries, Clear Creek, was found to be a point-source of cyanazine for the watershed.
Pollen-mediated gene flow between paraquat-resistant and susceptible hare barley (Hordeum leporinum)
Authors: Hidayat Imam , Baker Jeanine , Preston Christopher
Published: August 2006

Pollen movement between individuals can increase the rate of herbicide resistance evolution by spreading resistance alleles within or between populations and by facilitating the rapid accumulation of resistance alleles within individuals. This study investigated the level of pollen-mediated gene flow between paraquat-resistant and paraquat-susceptible populations of the self-pollinated weed species hare barley. The experiment was conducted in both directions, from resistant to susceptible and susceptible to resistant, across 2 yr. To maximize the potential for pollen flow, individual plants were grown in a single pot. The level of gene flow was similar across years and between genotypes. The level of pollen-mediated gene flow ranged from 0.06 to 0.15%. Gene flow from resistant to susceptible plants was confirmed by demonstrating segregation for resistance in the progeny of suspected crosses. This study suggests that pollen-mediated gene flow will occur in this species at frequencies less than 0.16% and could assist the accumulation of resistance alleles within a population. These low levels of gene flow through pollen movement suggest that cross-pollination over larger distances would be unlikely and pollen movement probably does not contribute to gene flow between populations.
Timing of tillage is an important filter on the assembly of weed communities
Authors: Smith Richard G.
Published: August 2006

A trait-based community assembly approach to weed management may enhance our understanding of how weed communities respond to specific management practices and increase the utility of weed management based on ecological principles. Therefore, identifying management practices that operate as assembly filters and the species traits upon which they act is an important first step in developing a more predictive weed science. Here, I report results from a 3-yr investigation of the effects of timing of annual tillage (spring vs. fall) on the annual assembly of arable weed communities. The timing of tillage had consistent and dramatic effects on the composition of weed communities; spring tillage led to weed communities dominated by early emerging spring annual forbs and C4 grasses, and fall tillage led to communities dominated by later-emerging forbs and C3 grasses. Traits determining a species' susceptibility to tillage time likely include germination syndrome and life cycle, both of which influence how species respond to changes in soil resource levels and light availability driven by seasonal disturbance regime. Manipulating the timing of tillage and other major soil disturbances may therefore be an important tool for managers interested in influencing community composition or targeting species with similar germination and life-history traits.
Physiological and antioxidant responses of cotton and spurred anoda (Anoda cristata) under nitrogen deficiency
Authors: Bettmann Greg T. , Ratnayaka H. Harish , Molin William T. , Sterling Tracy M.
Published: August 2006

Spurred anoda is a major competitor with cotton in the southern United States. Physiological and antioxidant responses of two species of cotton (Gossypium barbadenseL. cv. ‘Pima S-7’ andGossypium hirsutumL., Delta and Pine Land Company cv. ‘Delta Pine 5415’) and two accessions of spurred anoda [New Mexico (NM) and Mississippi (MS)] were investigated under nitrogen (N) -sufficient and -deficient conditions in the greenhouse. Pima S-7 had the highest leaf N content of all the plants regardless of treatment. Biomass decreased in all species when N was withheld, with Pima S-7 exhibiting the least reduction and MS the greatest. Plant height decreased in cotton but not spurred anoda under N stress. Height:node ratio increased 9% in MS, but decreased 8% in DP 5415 when they were deprived of N. Withholding N reduced photosynthesis 45% regardless of species. Comparable decreases were found in stomatal conductance and transpiration, suggesting strong stomatal regulation of gas exchange under N stress. The quantum efficiency of photosystem II (dark-adaptedFv/Fm) decreased 4% under N deficiency. Alpha-carotene decreased for all species when N was withheld, except for the NM accession, in which the levels increased. Total chlorophyll and lutein decreased under N stress regardless of species, but alpha-tocopherol and the xanthophyll cycle conversion state increased. Pima S-7 had the most chlorophyll and lutein, and both cotton species had more alpha-tocopherol, anthocyanins, and free-radical scavenging capacity than spurred anoda. These enhanced pigment and antioxidant profiles of cotton, particularly Pima S-7, may contribute to cotton's ability to compete for N with spurred anoda.
Herbicidal activity of glucosinolate-containing seedmeals
Authors: Vaughn Steven F. , Palmquist Debra E. , Duval Sandra M. , Berhow Mark A.
Published: August 2006

Defatted seedmeals from 15 glucosinolate-containing plant species were analyzed for herbicidal activity by determining inhibition of seedling emergence when added to a sandy loam soil containing wheat and sicklepod seeds at concentrations of 0.1, 0.5, and 1% (w/w). In general, the seedmeals were more phytotoxic to wheat than sicklepod. For wheat, all of the seedmeals significantly inhibited seedling emergence at the 1.0% concentration. At the 0.1% concentration three of the seedmeals (Indian mustard, money plant, and field pennycress) completely inhibited wheat emergence. For sicklepod emergence, eight of the seedmeals were completely inhibitory at the 1% level (Indian mustard, field pennycress, garden rocket, Siberian wallflower, English wallflower, garden cress, sweet alyssum, and evening stock) and four were completely inhibitory at the 0.5% level (brown mustard, garden rocket, English wallflower, and sweet alyssum). Intact glucosinolates and their corresponding hydrolysis products varied among the seedmeals with the highest activity. Major hydrolysis products produced by the seedmeals with the most phytotoxicity, respectively, included 2-propenyl (allyl) isothiocyanate (AITC) by brown mustard seedmeal, allyl thiocyanate and AITC by field pennycress seedmeal, erucin (4-methylthiobutyl isothiocyanate) by arugula seedmeal, 3-butenyl isothiocyanate and lesquerellin (6-methylthiohexyl isothiocyanate) by sweet alyssum seedmeal, and isopropyl isothiocyanate by money plant seedmeal. From our data it appears that both the type and concentration of glucosinolates and their hydrolysis products present in the seedmeals affect seed-emergence inhibition.
REPLACING RELATIVE REINFORCING EFFICACY WITH BEHAVIORAL ECONOMIC DEMAND CURVES
Authors: Johnson Matthew W. , Bickel Warren K.
Published: August 2006

Relative reinforcing efficacy refers to the behavior‐strengthening or maintaining property of a reinforcer when compared to that of another reinforcer. Traditional measures of relative reinforcing efficacy sometimes have led to discordant results across and within studies. By contrast, previous investigations have found traditional measures to be congruent with behavioral economic measures, which provide a framework for integrating the discordant results. This study tested whether the previously demonstrated congruence between traditional relative reinforcing efficacy measures and behavioral economic demand curve measures is sufficiently robust to persist when demand for one reinforcer is altered. Cigarette smokers pulled plungers for cigarettes or two magnitudes of money on progressive‐ratio schedules that increased the response requirement across sessions. Demand for the two different reinforcers was assessed in single‐schedule and concurrent‐schedule sessions. Demand curve measures Pmax and Omax correlated significantly with traditional measures of breakpoint and peak response rate, respectively. Relative locations of demand curves for money and cigarettes under single schedules predicted preference in concurrent schedules in most cases. Although measures of relative reinforcing efficacy for money changed with money magnitude, the congruence between traditional and behavioral economic measures remained intact. This robust congruence supports the proposal that demand curves should replace measures of relative reinforcing efficacy. The demand curve analysis illustrates why concordance between traditional measures is expected under some experimental conditions but not others.
Sampling Strategy for Intraoral Detection of Periodontal Pathogens Before and Following Periodontal Therapy
Authors: Beikler Thomas , Schnitzer Stefan , Abdeen Ghiath , Ehmke Benjamin , Eisenacher Martin , Flemmig Thomas F.
Published: August 2006

Background: The aim of this study was to identify a sampling strategy with high probability for detecting oral colonization by Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Eikenella corrodens, Tannerella forsythensis, Prevotella intermedia, Prevotella nigrescens, and Treponema denticola before and following mechanical periodontal therapy.

Methods: Samples were taken from the following intraoral sites in 35 patients with untreated chronic periodontitis before and 1.5, 3, and 6 months after non‐surgical periodontal therapy: supra‐ and subgingival plaque from the deepest pockets in each sextant; pooled supra‐ and subgingival plaque from another six randomly selected, less affected teeth; mucosal swab samples from the tongue, tonsils, throat, and buccal mucosa; and stimulated and unstimulated saliva. Microbial species were identified by polymerase chain reaction (PCR).

Results: Of the sampling of all assessed sites, the highest probability for simultaneously detecting the tested pathogens was found in respect to the combination of supra‐ and subgingival plaque samples taken from the most affected tooth in each sextant in untreated patients (probability: 83% to 95% for the assessed bacteria). These results were consistently observed throughout the study period.

Conclusions: For determining the intraoral carrier state of patients with periodontitis, a combined sample of supra‐ and subgingival plaque taken from the deepest periodontal pocket in each sextant may yield the most reliable result. This sampling strategy may be used in routine microbial testing and clinical research.
New Composite Endpoints to Assess Efficacy in Periodontal Therapy Clinical Trials
Authors: Lynch Samuel E. , Lavin Philip T. , Genco Robert J. , Beasley William G. , Wisner‐Lynch Leslie A.
Published: August 2006

Background: Clinical attachment level (CAL) and bone height (radiographic or clinical) are two well‐accepted endpoint measures for periodontal clinical trials; however, neither one has been shown to be more predictive of long‐term success than the other. We propose using a composite endpoint analysis combining clinical and radiological parameters to assess the beneficial effects on both hard and soft tissues following periodontal therapy using a single statistical test. To address this need, two composite endpoint alternatives are offered as a yardstick for clinical success; each includes the improvement in CAL and either improvement in linear bone growth or percent bone fill.

Methods: The data for composite endpoint analyses were derived from a clinical trial evaluating two concentrations of recombinant human platelet‐derived growth factor‐BB (rhPDGF‐BB) with beta‐tricalcium phosphate (β‐TCP) compared to β‐TCP plus buffer as follows: group I, β‐TCP + 0.3 mg/ml rhPDGF‐BB; group II, β‐TCP + 1.0 mg/ml rhPDGF‐BB; and group III, β‐TCP + buffer. The construction of composite endpoints was based on the greatest values for change, accepted by the U.S. Food and Drug Administration (FDA), for clinical attachment level (ΔCAL), mean change in radiographic linear bone gain (LBG), and mean radiographic percent bone fill (%BF), with the following dual standards defining a successful clinical result: CAL gain ≥2.67 mm and radiographic LBG ≥1.1 mm at 6 months and CAL gain ≥2.67 mm and radiographic %BF ≥14.1% at 6 months.

Results: Group I (β‐TCP + 0.3 mg/ml rhPDGF‐BB) demonstrated statistically significant differences from group III (active control) for both composite endpoints. For the CAL/LBG composite endpoint, 61.7% of sites in group I versus 30.4% of sites in group III met the composite endpoint benchmarks (P <0.001). For the CAL/%BF composite endpoint, 70% of sites in group I versus 44.6% of sites in group III met the composite endpoint benchmarks (P = 0.003). A non‐significant trend was observed for group II versus group III with 37.9% (P = 0.20) and 55.2% (P = 0.13) of sites meeting the CAL/LBG and CAL/%BF composite endpoints, respectively. These results are further emphasized by findings demonstrating a low correlation between the individual efficacy endpoints (ΔCAL and %BF; ΔCAL and LBG) for each of the three treatment groups.

Conclusions: Composite endpoints are advantageous in periodontal clinical trials where no single efficacy endpoint has been established as the most important. A composite endpoint, combining outcome measures of both hard and soft tissue components of the periodontium, may be preferable for assessing efficacy of periodontal regenerative therapies. Two composite endpoints are offered to meet this need.
Prostanoid– and Interleukin‐1–Induced Primary Genes in Cementoblastic Cells
Authors: Nervina Jeanne M. , Camargo Paulo M. , Bezouglaia Olga , Tetradis Sotirios
Published: August 2006

Background: Cementum is a key component of a functional periodontal organ. However, regenerating lost cementum is difficult and often incomplete. Identifying molecular mediators of cementoblast differentiation and function should lead to better targeted treatment for periodontitis. Prostaglandins increase mineralization of murine cementoblastic OCCM cells and alveolar bone formation, whereas the cytokine interleukin‐1 (IL‐1) inhibits alveolar bone formation. We hypothesized that differentially induced primary genes in OCCM cells may mediate anabolic and catabolic responses. Our objective was to identify primary genes differentially induced by the synthetic prostanoid fluprostenol and IL‐1 in cementoblastic cells.

Methods: Confluent OCCM cells were pretreated with the protein synthesis inhibitor cycloheximide followed by fluprostenol or IL‐1 for 1.5 hours. cDNA generated from each group was used for cDNA subtraction hybridization to identify differentially induced genes. Preferential gene induction was verified by Northern blot analysis.

Results: Thirteen fluprostenol‐ and seven IL‐1–regulated genes were identified. Among the fluprostenol‐induced genes was mitogen‐activated protein (MAP) kinase phosphatase 1 (MKP1), a negative regulator of MAP kinase signaling. To verify the cDNA subtraction hybridization results, OCCM cells were treated with fluprostenol or prostaglandin F2α (PGF2α), and MKP1 mRNA levels were determined. The 0.001 to 1 μM fluprostenol and 0.01 to 1 μM PGF2α significantly induced MKP1 mRNA levels, which peaked at 1 hour of treatment and returned to baseline at 2 hours.

Conclusions: Fluprostenol enhanced, whereas IL‐1 inhibited, OCCM mineralization. Using cDNA subtraction hybridization, we identified primary genes that correlate with the observed anabolic and catabolic responses. These findings further our understanding of cementoblast function and suggest that differentially induced genes may mediate cementum formation and resorption.
Clinical Efficacy of Flossing Versus Use of Antimicrobial Rinses
Authors: Zimmer Stefan , Kolbe Claudia , Kaiser Gerrit , Krage Tracy , Ommerborn Michelle , Barthel Claudia
Published: August 2006

Background: Dental floss is only used by a small part of the population on a daily basis. Therefore, an easy, applicable alternative is needed. This alternative could be a mouthrinse with antimicrobial activity for daily use. The aim of the present study was to evaluate the efficacy of two mouthrinses in reducing interdental plaque and gingivitis compared to dental floss.

Methods: A total of 156 healthy volunteers were randomly assigned to the following groups: 1) toothbrushing and rinsing (0.06% chlorhexidine and 0.025% fluoride); 2) toothbrushing and rinsing (0.1% cetylpyridiniumchloride and 0.025% fluoride); 3) toothbrushing and flossing; and 4) toothbrushing only (N = 39 subjects in each group). At baseline, the modified proximal plaque index (MPPI) and papillary bleeding index (PBI) were recorded. Thereafter, subjects had to brush in the usual manner during 8 weeks. Additionally, test groups had to rinse once a day (groups 1 and 2: 30 seconds) or to floss (group 3). Eight weeks after baseline, indices were recorded again and improvements were calculated. Analysis of variance (ANOVA) and the Bonferroni test served for statistical analysis.

Results: After 8 weeks, reductions for all indices were found in all groups (P <0.05). With respect to the MPPI, mouthrinse groups performed better than the control and floss groups: 1) 0.73; 2) 0.82; 3) 0.40; and 4) 0.32 (P <0.05). The PBI showed no statistically significant difference between groups: 1) 0.46; 2); 0.50; 3); 0.42; and 4) 0.37.

Conclusion: The results suggest that, in combination with toothbrushing, daily use of the tested mouthrinses may result in a higher interproximal plaque reduction than daily flossing.
Maintaining Primary Closure After Guided Bone Regeneration Procedures: Introduction of a New Flap Design and Preliminary Results
Authors: Fugazzotto Paul A.
Published: August 2006

Background: Various flap designs have been proposed by numerous authors for the maintenance of passive primary soft tissue closures following guided bone regeneration (GBR) procedures. A previous publication by the present author documented the maintenance of passive soft tissue primary closures 96.1% of the time at least 6 months after GBR therapy in all areas of the mouth. Although seemingly impressive, a 96.1% success rate means that there is premature membrane exposure 3.9% of the time. A new flap design is introduced for use in conjunction with previously described flap designs to lessen the incidence of premature membrane exposure.

Methods: A total of 173 sites treated with GBR therapy were examined up to 6 months postoperatively to assess the ability to maintain passive soft tissue primary closure. Any membrane exposure during this 6‐month postoperative period was deemed a failure, even if the site was successfully treated with an implant placement and restoration.

Results: A total of 171 of 173 GBR‐treated sites demonstrated the maintenance of a soft tissue passive primary closure 6 months postoperatively, yielding a success rate of 98.8%.

Conclusion: The introduction of the proposed flap design for use in conjunction with previously described flap designs significantly reduced the incidence of premature membrane exposure after a variety of GBR procedures.
Dental Plaque, Gingival Inflammation, and Elevated Levels of Interleukin‐6 and Cortisol in Gingival Crevicular Fluid From Women With Stress‐Related Depression and Exhaustion
Authors: Johannsen Annsofi , Rylander Gunnar , Söder Birgitta , Marie Åsberg
Published: August 2006

Background: The aim of the present study was to investigate the importance of stress for the development of periodontitis by comparing oral health status, proinflammatory markers, and cortisol in gingival crevicular fluid (GCF) and saliva in patients with stress‐related mental depression and controls.

Methods: The participants consisted of 43 women with stress‐related depression and exhaustion (Diagnostic and Statistical Manual of Mental Disorders, 4th edition [DSM‐IV]), with a mean age of 42.0 (±9.3 SD) years, and 29 controls, with a mean age of 54.5 (±2.9 SD) years. Clinical examination included the assessment of dental plaque, gingival inflammation (GI), bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), and number of teeth. GCF was collected with an intracrevicular washing technique from four sites in each subject. Interleukin (IL)‐1β, IL‐6, and matrix metalloproteinase‐9 were determined with enzyme‐linked immunosorbent assay and cortisol with radioimmunoassay (125I RIA). Analysis of covariance (one‐way covariance analyses) was used to remove the influence of age and smoking.

Results: The amount of plaque was significantly higher in patients compared to controls (P <0.003). The patients had an average GI of 1.53 (±0.13 SD) compared to 0.89 (±0.10 SD) for the controls (P <0.001). The levels of cortisol in GCF was significantly higher in patients than in controls, 3.46 nmol/l (±3.25 SD) and 0.30 nmol/l (±0.25 SD), respectively (P <0.001), whereas cortisol in saliva did not differ between groups. The levels of IL‐6 in GCF were significantly higher in the patients than in controls (P <0.05).

Conclusion: Women with stress‐related depression and exhaustion had more plaque accumulation, GI, and increased levels of IL‐6 and cortisol in GCF compared to normal controls, suggesting that depression might affect immune function, which could lead to impaired periodontal health.