Weed control with saturated steam in organic highbush blueberry

Weed management is often a predominant and costly problem in the production of organic blueberries. Geotextile weed fabrics of woven polyethylene are widely used in organic blueberry fields to suppress weeds growing within the rows. Weeds, such as Convolvulus arvensis L., grow at the base of the blueberry plants or through openings and around the edges of the weed fabric, thus requiring hand weeding. This study evaluates the integration of saturated steam (SS), a rotary brush (RB), and organic herbicides for weed control in blueberries. Dose–response studies indicated that SS applied at 121°C and at 7.4 m3 ha−1 of steam (3,655 MJ ha−1) resulted in over 90% control and a reduction in the dry weights of C. arvensis. When treatments were directed to the base of the blueberry plants, SS at 7.4 m3 ha−1 provided 80% control of C. arvensis 28 days after treatment (DAT) and was comparable to hand weeding. Both of these treatments outperformed capric plus caprylic acid (CC) (33.2 kg ai ha−1) or ammonium nonanoate (AN) (24.3 kg ai ha−1) applications, despite C. arversis regrowth being observed. Four repetitive basal applications of SS of up to 29.6 m3 ha−1 over two consecutive years caused minimal and transient damage to new basal shoots of ‘Elliot’ and ‘Duke’ blueberries; basal shoot cross-sectional area compared with the non-treated was unaffected. In contrast, basal application of AN treatments damaged or killed basal shoots. When treatments were applied to the edge of the weed fabric, SS (7.4 m3 ha−1) reduced weed biomass by 42% to 93% at 28 DAT compared with the non-treated. The RB treatment reduced weed biomass from 72% to 99% in all experiments, while CC and AN reduced biomass by 18% to 54%. A partial budget analysis indicated that SS and the RB were 3- and 6.5-fold less expensive than organic herbicides, respectively. Integrating physical (SS) and mechanical (RB) treatments improved weed control. The latter, however, damaged the weed-suppressing fabric where preexisting holes were present, generated dust, and increased the chance of fruit contamination. The SS was safe for the weed-suppressing fabric and the blueberry, but weed regrowth following treatment and copious water requirements hindered its feasibility

[a Socioeconomic Classification And The Discussion Related To Prevalence Of Dental Caries And Dental Fluorosis].

The aim of this study was to evaluate the relationship between a socioeconomic classification model and prevalence of dental caries and dental fluorosis in Piracicaba, Sâo Paulo, Brazil. For this classification five indicators were used (family monthly income, number of residents in the same household, parents' formal educational level, type of housing and occupation of person responsible for the family). A scoring system was used in order to arrange in a hierarchy, 812 12 year old school children distributed between six different social classes. Volunteers were examined in the school's back patio under natural light with a dental mirror, by two examiners calibrated for DMFT index (dental caries) and T-F (dental fluorosis). The qui-square test (p<0.01) was used in the statistical analysis for the association of DMFT and the dental fluorosis and between the socioeconomic variable and the proposed social classes. The DMFT average was 1.7, while 31.4%, of the children had dental fluorosis (T-Fe1). With respect to socioeconomic class a statistically significant association was only verified with dental caries.12523-

A socioeconomic classification and the discussion related to prevalence of dental caries and dental fluorosis

OBJECTIVE: The aim of this study was to evaluate the relationship between a socioeconomic classification model and prevalence of dental caries and dental fluorosis in Piracicaba, Sâo Paulo, Brazil. METHODS: For this classification five indicators were used (family monthly income, number of residents in the same household, parents' formal educational level, type of housing and occupation of person responsible for the family). A scoring system was used in order to arrange in a hierarchy, 812 12 year old school children distributed between six different social classes. Volunteers were examined in the school's back patio under natural light with a dental mirror, by two examiners calibrated for DMFT index (dental caries) and T-F (dental fluorosis). The qui-square test (p<0.01) was used in the statistical analysis for the association of DMFT and the dental fluorosis and between the socioeconomic variable and the proposed social classes. RESULTS: The DMFT average was 1.7, while 31.4%, of the children had dental fluorosis (T-Fe1). CONCLUSION: With respect to socioeconomic class a statistically significant association was only verified with dental caries.OBJETIVO: avaliar a relação entre classificação socioeconômica e a prevalência de cárie e fluorose dentária em Piracicaba, São Paulo,Brasil. MÉTODOS: A classificação foi baseada na seleção de cinco indicadores (renda familiar mensal, número de pessoas residentes na mesma moradia, grau de instrução dos pais, tipo de habitação e profissão do responsável pela família), buscando-se por sistema de pontuação hierarquizar 812 escolares na idade de 12 anos em até seis classes sociais distintas. Para a determinação da prevalência de cárie e fluorose dentária, os voluntários foram examinados no pátio das escolas, sob luz natural e com espelho bucal, por dois examinadores previamente calibrados para os índices CPO-D (WHO,1997) e T-F (Thylstrup & Fejerskov, 1978). O teste qui-quadrado (p<0,01) foi utilizado na análise estatística para a associação do CPO-D e da fluorose entre as variáveis socioeconômicas e entre as classes sociais propostas. RESULTADOS: Piracicaba apresentou média do CPO-D de 1,7, enquanto que em 31,4%, das crianças encontrou-se fluorose (T-F³1). CONCLUSÃO: em relação à classe socioeconômica, verificou-se associação estatisticamente significante somente com a cárie dentária.52352

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio