1,720,988 research outputs found
Alternative hosts for the mass creation of the parasitoid Tetrastichus howardi (Hymenoptera: Eulophidae)
No full textParasitoides são usados como inimigos naturais no controle biológico reduzindo populações de insetos pragas. A criação em massa desses inimigos naturais depende da disponibilidade de hospedeiros alternativos com baixo custo de produção e alta qualidade, sem reduzir a eficiência do hospedeiro natural. O parasitoide Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae), tem sido estudado como agente de controle biológico de espécies pragas de lepidópteras em culturas importantes. O objetivo deste estudo foi avaliar os parâmetros reprodutivos, qualidade da prole e a preferência do parasitoide T. howardi em pupas de Anticarsia gemmatalis, Spodoptera frugiperda e Tenebrio molitor. Pupas dos três hospedeiros foram individualizadas e expostas a um casal de T. howardi por 72 h. O número de indivíduos de T. howardi emergidos por pupa hospedeira, o ciclo de vida (ovo-adulto) e a razão sexual foram obtidos, e submetidos a análises morfométricas. A preferência do parasitoide nas pupas das três espécies hospedeiras foi obtido em testes de livre escolha. A sobrevivência de T. howardi, emergido de T. molitor e S. frugiperda foi maior, onde a troca de hospedeiro teve custo de sobrevivência inicial para os parasitoides emergidos de A. gemmatalis. Porém, o tamanho dos adultos emergidos de A. gemmatalis e S. frugiperda, foram maiores, sendo os mesmos, frequentemente, correlacionados com o tamanho e qualidade nutricional dos hospedeiros. O menor ciclo de vida de T. howardi em pupas de A. gemmatalis pode ser explicado pela competição entre larvas dos parasitoides onde grandes densidades e recursos limitados, diminuem o potencial de absorção dos nutrientes. O maior número de indivíduos emergidos de A. gemmatalis e S. frugiperda ocorreu devido a maiores quantidades de recursos nas pupas desses hospedeiros. A razão sexual, com predominância de fêmeas, foi semelhante. A preferência do parasitoide por pupas de A. gemmatalis e S. frugiperda, é uma resposta olfativa, onde a aceitação do hospedeiro é marcada pela oviposição. T. howardi não mostrou preferência por pupas de T. molitor, onde os hospedeiros alternativos, A. gemmatalis e S. frugiperda, apresentaram melhores condições de desenvolvimento e sejam preferíveis para a criação do parasitoide. Palavras-chave: Controle biológico. Morfometria. Pragas. Sobrevivência.Parasitoids are used as natural enemies in biological control by reducing populations of insect pests. The mass creation of these natural enemies depends on the availability of alternative hosts with low production cost and high quality, without reducing the efficiency of the natural host. The parasitoid Tetrastichus howardi (Olliff) (Hymenoptera: Eulophidae), has been studied as a biological control agent for lepidopteran pest species in important crops. The aim of this study was to evaluate the reproductive parameters, quality of offspring and the preference of the parasitoid T. howardi in pupae of Anticarsia gemmatalis, Spodoptera frugiperda and Tenebrio molitor. Pupae from the three hosts were individualized and exposed to a couple of T. howardi for 72 h. The number of T. howardi individuals emerged per host pupa, the life cycle (egg-adult) and the sex ratio were obtained, and submitted to morphometric analysis. The preference of the parasitoid in the pupae of the three host species was obtained in free choice tests. The survival of T. howardi, emerged from T. molitor and S. frugiperda was higher, where the change of host had an initial survival cost for the parasitoids emerged from A. gemmatalis. However, the size of the adults emerged from A. gemmatalis and S. frugiperda, were larger, and they are often correlated with the size and nutritional quality of the hosts. The shorter life cycle of T. howardi in pupae of A. gemmatalis can be explained by the competition between larvae of parasitoids, where large densities and limited resources, reduce the potential for nutrient absorption. The largest number of individuals emerged from A. gemmatalis and S. frugiperda occurred due to greater amounts of resources in the pupae of these hosts. The sex ratio, with a predominance of females, was similar. The preference of the parasitoid for pupae of A. gemmatalis and S. frugiperda, is an olfactory response, where host acceptance is marked by oviposition. T. howardi showed no preference for pupae of T. molitor, where the alternative hosts, A. gemmatalis and S. frugiperda, presented better development conditions and are preferable for the parasitoid creation. Keywords: Biological control. Morphometry. Pests. Survival.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Climate change impacts, adaptatition, and mititigatition in global agriculture
No full textClimate change has become an immediate and systemic stressor on global agrifood systems, with agriculture being both highly vulnerable to climate impacts and a major source of greenhouse gas emissions. Rising temperatures, water instability, soil degradation, and shifting pest and disease pressures are already reducing crop and livestock productivity, especially for smallholder farmers in Latin America, Sub-Saharan Africa, and South Asia. Using the Climate-Smart Agriculture framework, this editorial note highlights integrated responses that combine digital agriculture, agroecology, advanced breeding, and modeling for adaptation and mitigation. It emphasizes that technology alone is inadequate without strong institutions, inclusive knowledge systems, coherent policies, and green economy investments. Addressing persistent research gaps and moving beyond incremental change toward transformative and equitable transitions is essential to safeguard food security, livelihoods, and ecosystems while meeting climate goals.Climate change has become an immediate and systemic stressor on global agrifood systems, with agriculture being both highly vulnerable to climate impacts and a major source of greenhouse gas emissions. Rising temperatures, water instability, soil degradation, and shifting pest and disease pressures are already reducing crop and livestock productivity, especially for smallholder farmers in Latin America, Sub-Saharan Africa, and South Asia. Using the Climate-Smart Agriculture framework, this editorial note highlights integrated responses that combine digital agriculture, agroecology, advanced breeding, and modeling for adaptation and mitigation. It emphasizes that technology alone is inadequate without strong institutions, inclusive knowledge systems, coherent policies, and green economy investments. Addressing persistent research gaps and moving beyond incremental change toward transformative and equitable transitions is essential to safeguard food security, livelihoods, and ecosystems while meeting climate goals.Climate change has become an immediate and systemic stressor on global agrifood systems, with agriculture being both highly vulnerable to climate impacts and a major source of greenhouse gas emissions. Rising temperatures, water instability, soil degradation, and shifting pest and disease pressures are already reducing crop and livestock productivity, especially for smallholder farmers in Latin America, Sub-Saharan Africa, and South Asia. Using the Climate-Smart Agriculture framework, this editorial note highlights integrated responses that combine digital agriculture, agroecology, advanced breeding, and modeling for adaptation and mitigation. It emphasizes that technology alone is inadequate without strong institutions, inclusive knowledge systems, coherent policies, and green economy investments. Addressing persistent research gaps and moving beyond incremental change toward transformative and equitable transitions is essential to safeguard food security, livelihoods, and ecosystems while meeting climate goals
Compatibility of insecticides to the parasitoid Palmistichus elaeisis (Hymenoptera: Eulophidae)
No full textPalmistichus elaeisis Delvare & LaSalle (Hymenoptera: Eulophidae) é um endoparasitoide gregário que pode controlar pragas em culturas agrícolas e florestais. Inseticidas químicos podem causar efeitos colaterais em parasitoides e, portanto, devem ser investigados quanto a sua compatibilidade com esses agentes de controle. O objetivo deste estudo foi avaliar os efeitos subletais dos inseticidas abamectina, clorantraniliprole, clorfenapir e tiametoxam em P. elaeisis parasitando pupas de Anticarsia gemmatalis. Casais de P. elaeisis, com cerca de 24 horas da emergência, foram individualizados em tubos de vidro por 72 horas com uma pupa de A. gemmatalis tratada com os inseticidas (dose de campo) ou controle (apenas com água). A produção de imaturos, morfometria, sobrevivência e parâmetros reprodutivos de P. ela eisis foram avaliados. O número de imaturos produzidos por P. elaeisis foi menor em pupas de A. gemmatalis expostas aos inseticidas abamectina e tiametoxam que no controle. A largura do abdómen e da cabeça, de adultos emergidos de pupas tratadas com tiametoxam, foi menor que no controle. O comprimento da tíbia foi menor com abamectina, clorfenapir e tiametoxam. A largura do tórax do inseto foi menor com todos os inseticidas. A abamectina, tiametoxam e clorantraniliprole reduziram a probabilidade de sobrevivência de P. elaeisis em 35, 20 e 10 %, respectivamente, 31 dias após a emergência de fêmeas desse parasitoide. O período de desenvolvimento ovo-adulto, de parasitoides obtidos de pupas expostas ao tiametoxam, foi maior que o daquelas expostas ao clorantraniliprole. O número de adultos emergidos por hospedeiro e a proporção de fêmeas foram menores de pupas expostas ao tiametoxam que no controle. A toxicidade dos inseticidas abamectina, clorantraniliprole, clorfenapir e tiametoxam a P. elaeisis os tornam incompatíveis com esse parasitoide. Palavras-chave: Controle biológico. Controle químico. Longevidade. Razão sexual. Tamanho do corpo.Palmistichus elaeisis Delvare & LaSalle (Hymenoptera: Eulophidae) is a gregarious endoparasitoid that can control pests in agricultural and forest crops. Chemical insecticides can cause side effects in parasitoids and, therefore, they should be investigated for their compatibility with these control agents. The aim of this study was to evaluate the sublethal effects of the insecticides abamectin, chloranthranilprole, chlorfenapyr and thiamethoxam in P. elaeisis parasitizing pupae of Anticarsia gemmatalis. P. elaeisis couples, about 24 hours after emergence, were individualized in glass tubes for 72 hours with an A. gemmatalis pupa treated with insecticides (field dose) or control (only water). The production of immatures, morphometry, survival and reproductive parameters of P. elaeisis were evaluated. The number of immatures produced by P. elaeisis was lower in pupae of A. gemmatalis exposed to the insecticides abamectin and thiamethoxam than in the control. The width of the abdomen and head of adults emerging from pupae treated with thiamethoxam was smaller than in the control. The length of the tibia was shorter with abamectin, chlorfenapyr and thiamethoxam. The thorax width was smaller with all insecticides. Abamectin, thiamethoxam and chloranthraniliprole reduced the probability of P. elaeisis survival by 35, 20 and 10%, respectively, 31 days after the emergence of females of this parasitoid. The egg-adult development period of parasitoids obtained from pupae exposed to thiametoxam was longer than those exposed to chloranthranilprole. The number of adults emerged per host and the proportion of females were lower in pupae exposed to thiametoxam than in control. The toxicity of the insecticides abamectin, chlorantraniliprole, chlorfenapyr and thiamethoxam to P. elaeisis make them incompatible with this parasitoid. Keywords: Biological control. Body size. Chemical control. Longevity. Sex ratioCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
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