Carbon stock and its compartments in a subtropical oxisol under long-term tillage and crop rotation systems

Soil organic matter (SOM) plays a crucial role in soil quality and can act as an atmospheric C-CO2 sink under conservationist management systems. This study aimed to evaluate the long-term effects (19 years) of tillage (CT-conventional tillage and NT-no tillage) and crop rotations (R0-monoculture system, R1-winter crop rotation, and R2- intensive crop rotation) on total, particulate and mineral-associated organic carbon (C) stocks of an originally degraded Red Oxisol in Cruz Alta, RS, Southern Brazil. The climate is humid subtropical Cfa 2a (Köppen classification), the mean annual precipitation 1,774 mm and mean annual temperature 19.2 ºC. The plots were divided into four segments, of which each was sampled in the layers 0-0.05, 0.05-0.10, 0.10-0.20, and 0.20-0.30 m. Sampling was performed manually by opening small trenches. The SOM pools were determined by physical fractionation. Soil C stocks had a linear relationship with annual crop C inputs, regardless of the tillage systems. Thus, soil disturbance had a minor effect on SOM turnover. In the 0-0.30 m layer, soil C sequestration ranged from 0 to 0.51 Mg ha-1 yr-1, using the CT R0 treatment as base-line; crop rotation systems had more influence on soil stock C than tillage systems. The mean C sequestration rate of the cropping systems was 0.13 Mg ha-1 yr-1 higher in NT than CT. This result was associated to the higher C input by crops due to the improvement in soil quality under long-term no-tillage. The particulate C fraction was a sensitive indicator of soil management quality, while mineral-associated organic C was the main pool of atmospheric C fixed in this clayey Oxisol. The C retention in this stable SOM fraction accounts for 81 and 89 % of total C sequestration in the treatments NT R1 and NT R2, respectively, in relation to the same cropping systems under CT. The highest C management index was observed in NT R2, confirming the capacity of this soil management practice to improve the soil C stock qualitatively in relation to CT R0. The results highlighted the diversification of crop rotation with cover crops as a crucial strategy for atmospheric C-CO2 sequestration and SOM quality improvement in highly weathered subtropical Oxisols.

Tissue transglutaminase (TG2) activity regulates osteoblast differentiation and mineralization in the SAOS-2 cell line

Tissue transglutaminase (type II, TG2) has long been postulated to directly promote skeletal matrix calcification and play an important role in ossification. However, limited information is available on the expression, function and modulating mechanism of TG2 during osteoblast differentiation and mineralization. To address these issues, we cultured the well-established human osteosarcoma cell line SAOS-2 with osteo-inductive conditioned medium and set up three time points (culture days 4, 7, and 14) to represent different stages of SAOS-2 differentiation. Osteoblast markers, mineralization, as well as TG2 expression and activity, were then assayed in each stage. Furthermore, we inhibited TG activity with cystamine and then checked SAOS-2 differentiation and mineralization in each stage. The results showed that during the progression of osteoblast differentiation SAOS-2 cells presented significantly high levels of osteocalcin (OC) mRNA, bone morphogenetic protein-2 (BMP-2) and collagen I, significantly high alkaline phosphatase (ALP) activity, and the increased formation of calcified matrix. With the same tendency, TG2 expression and activity were up-regulated. Furthermore, inhibition of TG activity resulted in a significant decrease of OC, collagen I, and BMP-2 mRNA and of ALP activity and mineralization. This study demonstrated that TG2 is involved in osteoblast differentiation and may play a role in the initiation and regulation of the mineralization processes. Moreover, the modulating effects of TG2 on osteoblasts may be related to BMP-2.

Cellular and molecular studies of the effects of a selective COX-2 inhibitor celecoxib in the cardiac cell line H9c2 and their correlation with death mechanisms

Cardiovascular disease is one of the leading causes of death worldwide, and evidence indicates a correlation between the inflammatory process and cardiac dysfunction. Selective inhibitors of cyclooxygenase-2 (COX-2) enzyme are not recommended for long-term use because of potentially severe side effects to the heart. Considering this and the frequent prescribing of commercial celecoxib, the present study analyzed cellular and molecular effects of 1 and 10 µM celecoxib in a cell culture model. After a 24-h incubation, celecoxib reduced cell viability in a dose-dependent manner as also demonstrated in MTT assays. Furthermore, reverse transcription-polymerase chain reaction analysis showed that the drug modulated the expression level of genes related to death pathways, and Western blot analyses demonstrated a modulatory effect of the drug on COX-2 protein levels in cardiac cells. In addition, the results demonstrated a downregulation of prostaglandin E2 production by the cardiac cells incubated with celecoxib, in a dose-specific manner. These results are consistent with the decrease in cell viability and the presence of necrotic processes shown by Fourier transform infrared analysis, suggesting a direct correlation of prostanoids in cellular homeostasis and survival.

Five generations of peace operations: from the "thin blue line" to "painting a country blue"

This article combines both international practice and analytical contributions into a systematic and synthetic presentation of the evolution of peace operations from their modern inception in 1948 to the present. It seeks to serve a didactic purpose in proposing a basic structure for Brazilian scholars' burgeoning debate on peace operations and intervention, rather than a definitive characterization of blue helmet practice. Peace operations' progression is traced through five analytical "generations," each adding a crucial factor distinguishing it from its predecessors. Each generation is placed in relation to changes in the nature of conflict and in the interpretation of the foundational principles of peace operations, and links to broader theoretical issues in International Relations are made explicit at each stage.

Chemical treatment of papaya seeds aiming at long-term storage and control of damping off

Damping off is a nursery disease of great economic importance in papaya and seed treatment may be an effective measure to control. The aim of this work was to evaluate the quality of papaya seeds treated with fungicides and stored under two environmental and packaging conditions. Additionally, the efficiency of fungicide treatments in the control of damping-off caused by Rhizoctonia solani was evaluated. Papaya seeds were treated with the fungicides Captan, Tolylfluanid and the mixture Tolylfluanid + Captan (all commercial wettable powder formulations). Seeds of the control group were not treated. The seeds were stored for nine months in two conditions: packed in aluminum coated paper and kept at 7 ± 1ºC and in permeable kraft paper and kept in non-controlled environment. At the beginning of the storage and every three months the seed quality (germination and vigor tests), emergence rate index, height, dry mass and damping of plants in pre and post-emergence (in contaminated substrate and mycelia-free substrate) were analyzed. Both storage conditions as well as the fungicide treatments preserved the germination and seed vigor. In the infested substrate, seedling emergence was favored by fungicides, but in post-emergence, fungicides alone did not control the damping off caused by R. solani. Symptoms of damping off were not observed in the clean substrate. The results showed that the fungicide treatments may be used to pretreat papaya seed for long-term storage and commercialization.

Is the pollination efficiency of long-lived orchid flowers affected by age?

The long-lived flowers of orchids increase the chances of pollination and thus the reproductive success of the species. However, a question arises: does the efficiency of pollination, expressed by fruit set, vary with the flower age? The objective of this study was to verify whether the flower age of Corymborkis flava(Sw.) Kuntze affects pollination efficiency. The following hypotheses were tested: 1) the fruit set of older flowers is lower than that of younger ones; 2) morphological observations (perianth and stigmatic area), stigma receptivity test by using a solution of hydrogen peroxide and hand-pollination tests are equally effective in defining the period of stigmatic receptivity. Flowers were found to be receptive from the first to the fourth day of anthesis. Fruit set of older flowers (third and fourth day) was lower than that of younger flowers. Morphological observations, the stigma receptivity test and hand-pollinations were equally effective in defining the period of stigmatic receptivity. However, to evaluate the maximum degree of stigma receptivity of orchid species with long-lived flowers, we recommend hand-pollinations, beyond the period of receptivity.

Fatores de impacto no sucesso do marketing boca a boca on-line

O marketing boca a boca caracteriza-se pela divulgação de produtos e serviços por canais interpessoais e consiste em um componente essencial no composto de comunicação de diversas empresas. Nesse sentido, o crescimento do número de consumidores conectados à Internet motiva as empresas a buscarem caminhos para maximizar o marketing boca a boca por meio de ferramentas on-line, como o marketing viral. Com o objetivo de identificar as principais características de uma ação eficaz de marketing boca a boca virtual, realizou-se uma pesquisa exploratória com usuários de Internet em janeiro e fevereiro de 2001. Ao final, são indicados seis fatores que podem influenciar o sucesso do marketing boca a boca virtual.

Conhecendo o "valor do cliente" de um jornal on-line

Com o advento da Internet, uma questão parece peculiar ao marketing: conhecer o comportamento de um "novo" consumidor, o on-line. Uma proposta é o conhecimento do "valor do cliente", que é a percepção do consumidor sobre como atributos de produtos podem propiciar benefícios que o ajudem a atingir suas metas. A teoria de cadeias de meios-fim é a forma de se pensar sistematicamente nessa representação. O método mais amplamente utilizado para atingir as cadeias de meios-fim é o laddering. A pesquisa foi realizada com uma amostra de 78 usuários de um grande jornal on-line. Os principais "valores do cliente" dos usuários do jornal propiciaram conclusões importantes. Foram identificados leitores que se preocupam muito com seus objetivos pessoais, mas que também desejam interagir com os outros e que demonstraram interesse com questões sociais. Com base nisso, implicações gerenciais são discutidas e sugestões para futuras pesquisas são indicadas.

A compra por impulso em ambientes on-line

Este estudo tem como propósito avaliar os antecedentes e as conseqüências da compra por impulso em lojas virtuais da Internet. Para tanto, foi desenvolvido um modelo teórico que procura apresentar as relações existentes entre o ambiente de loja (site), a impulsividade individual, a circulação na loja (navegação no site) e a realização de compras impulsivas. A partir de uma pesquisa survey realizada com compradores de produtos pela Internet, por meio de modelagem de equações estruturais, foi evidenciado que o ambiente do site afeta o nível de impulsividade, a navegação no site e a ocorrência de compras por impulso, bem como se encontrou uma relação entre compra por impulso e emoções positivas. Elementos ambientais que influenciam a compra por impulso foram identificados e rotas para futuras pesquisas apresentadas, juntamente com implicações acadêmicas e gerenciais dos resultados.

Inovatividade, envolvimento, atitude e experiência na adoção da compra on-line

Este trabalho procura analisar as inter-relações entre a inovatividade, o envolvimento, a atitude dentro do modelo Theory of Planned Behavior (TPB) decomposto desenvolvido na psicologia social, e a experiência com a Internet com o processo de adoção da compra pela internet. Foi elaborado um modelo integrativo que possibilitasse explicar a relação entre esses fatores e a compra pela internet, e foi desenvolvida uma pesquisa de campo considerando uma amostra não probabilística de estudantes. Foi utilizado o método multivariado de modelagem de equações estruturais, aplicado por meio da técnica Partial Least Squares (PLS) para a verificação, explicação e comparação das relações entre os construtos. Os resultados mostram que a intenção da compra pela internet é diretamente influenciada pela atitude e pela inovatividade, e a atitude é influenciada pelo envolvimento. Não foi encontrada relação entre a experiência com a internet e a compra pela internet.

RC-IAL cell line: sensitivity of rubella virus grow

OBJECTIVE: The rapid growth of the rubella virus in RC-IAL² with development of cytopathic effect, in response to rubella virus infection, is described. For purposes of comparison, the rubella virus RA-27/3 strain was titered simultaneously in the RC-IAL, Vero, SIRC and RK13 cell lines. METHODS: Rubella virus RA-27/3 strain are inoculated in the RC-IAL cell line (rabbit Kidney, Institute Adolfo Lutz). Plates containing 1.5x10(5) cells/ml of RC-IAL line were inoculated with 0.1ml s RA-27/3 strain virus containing 1x 10(4)TCID50/0.1ml. A 25% cytopathic effect was observed after 48 hours and 100% after 96 hours. The results obtained were compared to those observed with the SIRC, Vero and RK13 cell lines. Rubella virus was detected by immunohistochemistry. RESULTS: With the results, it was possible to conclude that the RC-IAL cell line is a very good substrate for culturing rubella virus. The cells inoculated with rubella virus were examined by phase contrast microscopy and showed the characteristic rounded, bipolar and multipolar cells. The CPE in RC-IAL was observed in the first 48 hours and the curve of the increased infectivity was practically the same as observed in other cell lines. CONCLUSIONS: These findings are important since this is one the few cell lines described in the literature with a cytopathic effect. So it can be used for antigen preparation and serological testing for the diagnosis of specific rubella antibodies.

Autonomy of long-stay psychiatric inpatients

OBJECTIVE: To assess personal autonomy of long-stay psychiatric inpatients, to identify those patients who could be discharged and to evaluate the impact of sociodemographic variables, social functioning, and physical disabilities on their autonomy was also assessed. METHODS: A total of 584 long-stay individuals of a psychiatric hospital (96% of the hospital population) in Southern Brazil was assessed between July and August 2002. The following instruments, adapted to the Brazilian reality, were used: independent living skills survey, social behavioral schedule, and questionnaire for assessing physical disability. RESULTS: Patients showed severe impairment of their personal autonomy, especially concerning money management, work-related skills and leisure, food preparation, and use of transportation. Autonomy deterioration was associated with length of stay (OR=1.02), greater physical disability (OR=1.54; p=0.01), and male gender (OR=3.11; p<0.001). The risk estimate of autonomy deterioration was 23 times greater among those individuals with severe impairment of social functioning (95% CI: 10.67-49.24). CONCLUSIONS: In-patients studied showed serious impairment of autonomy. While planning these patients' discharge their deficits should be taken into consideration. Assessment of patients' ability to function and to be autonomous helps in identifying their needs for care and to evaluate their actual possibilities of social reinsertion.

Long-stay patients in a psychiatric hospital in Southern Brazil

OBJECTIVE: To describe the demographic profile, social functioning, and quality of life of a population of long-stay care patients in a psychiatric hospital. METHODS: A study was carried out in Porto Alegre, Southern Brazil, in 2002. A total of 584 (96%) long-stay patients were assessed by means of the following instruments: the World Health Organization Quality of Life, the Social Behavior Schedule, the Independent Living Skills Survey, the Brief Psychiatric Rating Scale and another instrument for assessing disability (Questionnaire for Assessing Physical Disability). RESULTS: The average hospital stay was 26 years (SD: 15.8) and 46.6% of inpatients had no physical disability. Patients had their social functioning skills and autonomy largely impaired. Few of them (27.7%) answered the instrument for assessing quality of life, and showed significant impairments in all domains. The Brief Psychiatric Rating Scale evidenced a low prevalence of positive symptoms in this population. CONCLUSIONS: The institutionalized population studied presented significantly impaired social functioning, autonomy, and quality of life. These aspects need to be taken into consideration while planning for their deinstitutionalization.

Long-term health benefits of appetite suppressants remain unproven

Because of the increasing prevalence of obesity, prevention and treatment of overweight has become a major public health concern. In addition to diet and exercise, drugs are needed for patients who failed to lose weight with behavioral treatment. The current article aimed to summarize recent concerns on the safety and efficacy of appetite suppressants. Several appetite suppressants have been banned for safety reasons. In 2010, sibutramine was withdrawn from the market because a long-term study showed it increased the risks of cardiovascular events. So far no study with a sufficiently large sample size has demonstrated that appetite suppressants can reduce morbidity and mortality associated with overweight. The withdrawal of sibutramine highlights that guidelines for the evaluation of weight control drugs must be more stringent, and studies on their long-term health benefits are needed prior to their marketing.

Impact of long-stay beds on the performance of a tertiary hospital in emergencies

ABSTRACT OBJECTIVE To assess the impact of implementing long-stay beds for patients of low complexity and high dependency in small hospitals on the performance of an emergency referral tertiary hospital. METHODS For this longitudinal study, we identified hospitals in three municipalities of a regional department of health covered by tertiary care that supplied 10 long-stay beds each. Patients were transferred to hospitals in those municipalities based on a specific protocol. The outcome of transferred patients was obtained by daily monitoring. Confounding factors were adjusted by Cox logistic and semiparametric regression. RESULTS Between September 1, 2013 and September 30, 2014, 97 patients were transferred, 72.1% male, with a mean age of 60.5 years (SD = 1.9), for which 108 transfers were performed. Of these patients, 41.7% died, 33.3% were discharged, 15.7% returned to tertiary care, and only 9.3% tertiary remained hospitalized until the end of the analysis period. We estimated the Charlson comorbidity index – 0 (n = 28 [25.9%]), 1 (n = 31 [56.5%]) and ≥ 2 (n = 19 [17.5%]) – the only variable that increased the chance of death or return to the tertiary hospital (Odds Ratio = 2.4; 95%CI 1.3;4.4). The length of stay in long-stay beds was 4,253 patient days, which would represent 607 patients at the tertiary hospital, considering the average hospital stay of seven days. The tertiary hospital increased the number of patients treated in 50.0% for Intensive Care, 66.0% for Neurology and 9.3% in total. Patients stayed in long-stay beds mainly in the first 30 (50.0%) and 60 (75.0%) days. CONCLUSIONS Implementing long-stay beds increased the number of patients treated in tertiary care, both in general and in system bottleneck areas such as Neurology and Intensive Care. The Charlson index of comorbidity is associated with the chance of patient death or return to tertiary care, even when adjusted for possible confounding factors.