RESUMO
Abstract Worldwide, conventional agriculture makes extensive use of pesticides. Although the effects of herbicides are relatively well known in terms of environmental impacts on non-target organisms, there is very little scientific evidence regarding the impacts of herbicide residues on aquatic arthropods from tropical conservation areas. This study evaluates for the first time the toxicity of the herbicides ametryn, atrazine, and clomazone on the aquatic insect Limnocoris submontandoni (Hemiptera: Naucoridae). The lethal concentration (LC50) of herbicides was evaluated for these insects, as well as the effect of the herbicides on the insects tissues and testicles. The estimated LC50 was 1012.41, 192.42, and 46.09 mg/L for clomazone, atrazine, and ametryn, respectively. Spermatocyte and spermatid changes were observed under the effect of atrazine, and effects on spermatogenesis were observed for some concentrations of clomazone, with apparent recovery after a short time. Our results provide useful information on the effects of herbicide residues in aquatic systems. This information can help minimize the risk of long-term reproductive effects in non-target species that have been previously overlooked in ecotoxicology studies.
Resumo Em todo o mundo, a agricultura convencional faz uso extensivo de pesticidas. Embora os efeitos dos herbicidas sejam relativamente bem conhecidos em termos de impactos ambientais em organismos não-alvo, há pouca evidência científica sobre os impactos de resíduos de herbicidas em artrópodes aquáticos de áreas de conservação tropicais. Este estudo avalia pela primeira vez a toxicidade dos herbicidas ametryn, atrazine e clomazone sobre o inseto aquático Limnocoris submontandoni (Hemiptera: Naucoridae). A concentração letal (LC50) de herbicidas foi avaliada para esses insetos, bem como o efeito dos herbicidas nos tecidos e testículos dos insetos. A LC50 estimada foi de 1012,41, 192,42 e 46,09 mg/L para clomazone, atrazine e ametryn, respectivamente. Alterações nos espermatócitos e espermátides foram observadas sob o efeito de atrazine, e efeitos na espermatogênese foram observados para algumas concentrações de clomazone, com aparente recuperação após um curto período de tempo. Nossos resultados fornecem informações úteis sobre os efeitos de resíduos de herbicidas em sistemas aquáticos. Essas informações podem ajudar a minimizar o risco de efeitos reprodutivos de longo prazo em espécies não-alvo que foram negligenciadas anteriormente em estudos de ecotoxicologia.
RESUMO
Abstract Worldwide, conventional agriculture makes extensive use of pesticides. Although the effects of herbicides are relatively well known in terms of environmental impacts on non-target organisms, there is very little scientific evidence regarding the impacts of herbicide residues on aquatic arthropods from tropical conservation areas. This study evaluates for the first time the toxicity of the herbicides ametryn, atrazine, and clomazone on the aquatic insect Limnocoris submontandoni (Hemiptera: Naucoridae). The lethal concentration (LC50) of herbicides was evaluated for these insects, as well as the effect of the herbicides on the insects' tissues and testicles. The estimated LC50 was 1012.41, 192.42, and 46.09 mg/L for clomazone, atrazine, and ametryn, respectively. Spermatocyte and spermatid changes were observed under the effect of atrazine, and effects on spermatogenesis were observed for some concentrations of clomazone, with apparent recovery after a short time. Our results provide useful information on the effects of herbicide residues in aquatic systems. This information can help minimize the risk of long-term reproductive effects in non-target species that have been previously overlooked in ecotoxicology studies.
Resumo Em todo o mundo, a agricultura convencional faz uso extensivo de pesticidas. Embora os efeitos dos herbicidas sejam relativamente bem conhecidos em termos de impactos ambientais em organismos não-alvo, há pouca evidência científica sobre os impactos de resíduos de herbicidas em artrópodes aquáticos de áreas de conservação tropicais. Este estudo avalia pela primeira vez a toxicidade dos herbicidas ametryn, atrazine e clomazone sobre o inseto aquático Limnocoris submontandoni (Hemiptera: Naucoridae). A concentração letal (LC50) de herbicidas foi avaliada para esses insetos, bem como o efeito dos herbicidas nos tecidos e testículos dos insetos. A LC50 estimada foi de 1012,41, 192,42 e 46,09 mg/L para clomazone, atrazine e ametryn, respectivamente. Alterações nos espermatócitos e espermátides foram observadas sob o efeito de atrazine, e efeitos na espermatogênese foram observados para algumas concentrações de clomazone, com aparente recuperação após um curto período de tempo. Nossos resultados fornecem informações úteis sobre os efeitos de resíduos de herbicidas em sistemas aquáticos. Essas informações podem ajudar a minimizar o risco de efeitos reprodutivos de longo prazo em espécies não-alvo que foram negligenciadas anteriormente em estudos de ecotoxicologia.
Assuntos
Animais , Artrópodes , Poluentes Químicos da Água/toxicidade , Hemípteros , Herbicidas/toxicidade , Ecotoxicologia , GenitáliaRESUMO
Trees occurring on the margins of agricultural areas can mitigate damage from residual herbicides. Rhizospheric microbial activity associated with trees is one of the main remedial capacity indicators. The objective of this study was to evaluate the rhizospheric microbiological activity in tree species subjected to the herbicides atrazine and sulfentrazone via the rhizosphere. The experiment was designed in four blocks and a 6 × 3 factorial scheme. The first factor consisted of six tree species from Brazil and the second of atrazine, sulfentrazone, and water solutions. Four herbicide applications were performed via irrigation. The total dry mass of the plants, mycorrhizal colonization, number of spores, basal respiration of the rhizospheric soil, and survival rate of bioindicator plants after phytoremediation were determined. Trichilia hirta had higher biomass when treated with atrazine and sulfentrazone. Herbicides decreased the microbial activity in Triplaris americana and did not affect the microbiological indicators of Myrsine gardneriana, Schizolobium parahyba, and Toona ciliata. Fewer bioindicator plants survived in soil with Triplaris americana and sulfentrazone. Microbiological indicators were influenced in different ways between species by the presence of herbicides in the rhizosphere.(AU)
As árvores que ocorrem nas margens das áreas agrícolas podem mitigar os danos dos herbicidas residuais. A atividade microbiana rizosférica associada às árvores é um dos principais indicadores de capacidade corretiva. O objetivo deste trabalho foi avaliar a atividade microbiológica rizosférica em espécies arbóreas submetidas aos herbicidas atrazina e sulfentrazone via rizosfera. O experimento foi estruturado em quatro blocos e esquema fatorial 6 × 3. O primeiro fator consistiu em seis espécies de árvores do Brasil e o segundo em soluções de atrazine, sulfentrazone e água. Quatro aplicações de herbicidas foram realizadas via irrigação. Foram determinados a massa seca total das plantas, colonização micorrízica, número de esporos, respiração basal do solo rizosférico e taxa de sobrevivência de plantas bioindicadoras após fitorremediação. Trichilia hirta apresentou maior biomassa quando tratada com atrazina e sulfentrazone. Os herbicidas diminuíram a atividade microbiana em Triplaris americana e não afetaram os indicadores microbiológicos de Myrsine gardneriana, Schizolobium parahyba e Toona ciliata. Menos plantas bioindicadoras sobreviveram no solo com Triplaris americana e sulfentrazone. Os indicadores microbiológicos foram influenciados de formas distintas entre as espécies pela presença dos herbicidas na rizosfera.(AU)
Assuntos
Rizosfera , Meliaceae/efeitos dos fármacos , Meliaceae/microbiologia , Polygonaceae/efeitos dos fármacos , Polygonaceae/microbiologia , Myrsine/efeitos dos fármacos , Myrsine/microbiologia , Fabaceae/efeitos dos fármacos , Fabaceae/microbiologia , Herbicidas/administração & dosagem , AtrazinaRESUMO
Trees occurring on the margins of agricultural areas can mitigate damage from residual herbicides. Rhizospheric microbial activity associated with trees is one of the main remedial capacity indicators. The objective of this study was to evaluate the rhizospheric microbiological activity in tree species subjected to the herbicides atrazine and sulfentrazone via the rhizosphere. The experiment was designed in four blocks and a 6 × 3 factorial scheme. The first factor consisted of six tree species from Brazil and the second of atrazine, sulfentrazone, and water solutions. Four herbicide applications were performed via irrigation. The total dry mass of the plants, mycorrhizal colonization, number of spores, basal respiration of the rhizospheric soil, and survival rate of bioindicator plants after phytoremediation were determined. Trichilia hirta had higher biomass when treated with atrazine and sulfentrazone. Herbicides decreased the microbial activity in Triplaris americana and did not affect the microbiological indicators of Myrsine gardneriana, Schizolobium parahyba, and Toona ciliata. Fewer bioindicator plants survived in soil with Triplaris americana and sulfentrazone. Microbiological indicators were influenced in different ways between species by the presence of herbicides in the rhizosphere.
As árvores que ocorrem nas margens das áreas agrícolas podem mitigar os danos dos herbicidas residuais. A atividade microbiana rizosférica associada às árvores é um dos principais indicadores de capacidade corretiva. O objetivo deste trabalho foi avaliar a atividade microbiológica rizosférica em espécies arbóreas submetidas aos herbicidas atrazina e sulfentrazone via rizosfera. O experimento foi estruturado em quatro blocos e esquema fatorial 6 × 3. O primeiro fator consistiu em seis espécies de árvores do Brasil e o segundo em soluções de atrazine, sulfentrazone e água. Quatro aplicações de herbicidas foram realizadas via irrigação. Foram determinados a massa seca total das plantas, colonização micorrízica, número de esporos, respiração basal do solo rizosférico e taxa de sobrevivência de plantas bioindicadoras após fitorremediação. Trichilia hirta apresentou maior biomassa quando tratada com atrazina e sulfentrazone. Os herbicidas diminuíram a atividade microbiana em Triplaris americana e não afetaram os indicadores microbiológicos de Myrsine gardneriana, Schizolobium parahyba e Toona ciliata. Menos plantas bioindicadoras sobreviveram no solo com Triplaris americana e sulfentrazone. Os indicadores microbiológicos foram influenciados de formas distintas entre as espécies pela presença dos herbicidas na rizosfera.
Assuntos
Fabaceae/efeitos dos fármacos , Fabaceae/microbiologia , Herbicidas/administração & dosagem , Meliaceae/efeitos dos fármacos , Meliaceae/microbiologia , Myrsine/efeitos dos fármacos , Myrsine/microbiologia , Polygonaceae/efeitos dos fármacos , Polygonaceae/microbiologia , Rizosfera , AtrazinaRESUMO
Edaphic predatory mites could be introduced in pest management programs of pests that live, or spend part of their life cycle, in the soil. Some mesostigmatic mites have been widely used for the management of different species of thrips (Thysanoptera), especially in protected cultivation. The edaphic predator Cosmolaelaps sabelis (Mesostigmata: Laelapidae) was a model species in this study, being exposed to the most applied insecticides for the control of thrips in Brazil. After lethal, sublethal and transgenerational effects were evaluated. The pesticides acephate, acetamiprid + etofenprox, azadirachtin, spinetoram, formetanate hydrochloride, and imidacloprid were classified according to the IOBC/WPRS (International Organization for Biological Control-West Paleartic Regional Section) recommendation, considering the acute toxicity and the effects on adult females' reproduction, in the maternal and first generation. The pesticides acetamiprid + etofenprox and azadirachtin were classified as slightly harmful (Class 2), while spinetoram was classified as moderately harmful (Class 3). Acephate and formetanate hydrochloride were classified as harmful (Class 4). Only imidacloprid didn't cause negative effects on the females. Regarding effects on the first generation, acetamiprid + etofenprox, azadirachtin, and spinetoram caused reduction in the oviposition rates. Therefore, we suggest that complimentary bioassays should be done under semi-field and field conditions using the pesticides that were considered harmful in this study, to assess their effects on this predator in other environments prior to recommending not to use them in integrated programs to manage soil-based pests using chemical and biological tools.
Assuntos
Ácaros , Praguicidas , Tisanópteros , Animais , Feminino , Controle Biológico de Vetores , Praguicidas/farmacologia , Comportamento Predatório , SoloRESUMO
Data analytics techniques have been gaining more space in the scientific environment with applications in various areas of knowledge, including education. This paper aims to analyse data taken from a questionnaire of the Organization for Economic Development Cooperation (OECD) given to teachers and school managers. In this questionnaire, school environment issues are assessed, specifically: school environment, professional development, school leadership, and efficient management. As a methodology, Teaching and Learning Analytics (TLA) was used, particularly correlation analysis, which enables the extraction of useful information from raw data, relating issues that interfere with the teaching and learning relationship, besides specific analysis of student learning. The results obtained about the school environment are not linear. They do not present moderate or a solid linear correlation, making it impossible to validate and integrate answers related to the statements of the themes and sub-themes chosen for this analysis. In this sense, the research found dichotomous observations that mirrored many controversies and insecurities, enabling considerations about possible school scenarios and their effective practices.
RESUMO
Worldwide, conventional agriculture makes extensive use of pesticides. Although the effects of herbicides are relatively well known in terms of environmental impacts on non-target organisms, there is very little scientific evidence regarding the impacts of herbicide residues on aquatic arthropods from tropical conservation areas. This study evaluates for the first time the toxicity of the herbicides ametryn, atrazine, and clomazone on the aquatic insect Limnocoris submontandoni (Hemiptera: Naucoridae). The lethal concentration (LC50) of herbicides was evaluated for these insects, as well as the effect of the herbicides on the insects' tissues and testicles. The estimated LC50 was 1012.41, 192.42, and 46.09 mg/L for clomazone, atrazine, and ametryn, respectively. Spermatocyte and spermatid changes were observed under the effect of atrazine, and effects on spermatogenesis were observed for some concentrations of clomazone, with apparent recovery after a short time. Our results provide useful information on the effects of herbicide residues in aquatic systems. This information can help minimize the risk of long-term reproductive effects in non-target species that have been previously overlooked in ecotoxicology studies.
Assuntos
Artrópodes , Hemípteros , Herbicidas , Poluentes Químicos da Água , Animais , Ecotoxicologia , Genitália , Herbicidas/toxicidade , Poluentes Químicos da Água/toxicidadeRESUMO
Watershed studies that account for nutrient loadings are crucial for suitable river basin and estuarine management. This study aims to contribute to the environmental planning and decision making regarding nitrogen and phosphorus loadings for the watershed of the Vitória Bay Estuarine System (VBES; 1925 km2) in southeast Brazil. Here, we estimate that the VBES had annual loadings (in 2016) from ten tributary river basins of 5480 and 10,784 t for P and N, respectively, based on emission factors for natural and anthropogenic sources. The main contribution sources were related to livestock farming (4801 t of P and 8000 t of N) and domestic wastewater (492 t of P and 1706 t of N). However, urban loadings have higher expressions when considering the input by watershed area (0.25 and 0.87 t km-2 year-1 of P and N yields, respectively), which are mainly due to wastewater since 70% of the sewage is untreated. Urban emissions play a prominent role and have a tendency to be aggravated due to Brazilian population growth (0.8% annual rate). If the current wastewater emissions continue, P and N loadings will likely increase by 1.316% to totals of 713 and 2474 t year-1 in 2050 for P and N, respectively. Considering that the wastewater tertiary treatment cost is US$ 0.50 m-3, and that in the future 70% of all wastewater will be collected, the P and N loadings will drop to 18.4 and 424.1 t year-1, respectively, with a treatment cost of 25 million USD year-1. The model holds well for non-regulated watersheds. However, for regulated basins, such as the Santa Maria de Vitória, the model overestimates the loadings mainly due to the damming systems in these watersheds (accounting for 49% retention of P and 0.13% retention of N).
Assuntos
Monitoramento Ambiental , Nitrogênio/análise , Fósforo/análise , Rios/química , Esgotos/química , Solo/química , Animais , Brasil , Gado , Modelos Teóricos , Tecnologia de Sensoriamento Remoto , Purificação da Água/economiaRESUMO
The interactive function between intrafollicular factors related with ovum competence and embryo development played an important role getting high quality embryos during the embryo transference in in-vitro fertilization programs. Urinary gonadotropins are used widely to get homogeneous follicles during ovarian stimulation. Recombinant technology has been applied in these compounds to correlate with a best egg formation and higher pregnancy rates. We developed a prospective, linear and comparative study to aim the ovum/embryo development using urinary and recombinant FSH. A total of 100 patients were included in the study, 56 patients received rFSH (group I) and 44 hMG (group II). There were not differences in age, weight and body mass index as well as ovarian reserve. However, patients who used urinary gonadotrophins required a higher number of ampoules [31.7 +/- 8.6 vs. 20.7 +/- 6.4 (p < 0.001)]. No differences in peak E2, day of hCG and endometrial thickness. Although, no differences in number of egg mature, the fertilization rate was higher in the recombinant group [5.9 +/- 3.7 vs. 3.4 +/- 2.3 (p < 0.02)]. A higher number of embryo transfer were observed in the same group (3.4 +/- 1.7 vs. 1.9 +/- 2.2 (p < 0.004)]. The pregnancy rates were 34.3% and 29.6% for each group respectively.
Assuntos
Fertilização in vitro , Hormônio Foliculoestimulante/farmacologia , Hormônio Foliculoestimulante/urina , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/urina , Adulto , Feminino , Humanos , Gravidez/estatística & dados numéricos , Estudos ProspectivosRESUMO
In recent years endoscopic surgery has became a highly demanded procedure because it is an easy method for diagnosis and treatment in gynecological field. Post-operative pain is considered as a condition in the morbidity status. The objective of this study was to evaluate the nociceptive suppression in laparoscopic surgery. A prospective randomized trial was performed in order to evaluate this condition. A total of 45 patients were included. Three groups were randomized using two different anesthetics applied in the cult-de-sac and uterine-bladder union. Group A (n-15) received bupivacaine, group B (n = 15) ropivacaine and group C (control) saline solution was instilled. The pain was scored using the visual analog scale as same as blood pressure and heart rate in a 15 minute intervals in the recovery room. For study design there were no differences in age, weight, height and body mass index (EMI). The surgical and anesthetic times were similar among groups. However there were significant differences when pain was evaluated. For a less toxic effects and good preventive analgesia we recommend to use ropivacaine in the postoperative status.