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Imunobiologia das infestações de bovinos pelo carrapato Rhipicephalus (Boophilus) microplus: estudo dos correlatos imunes de resistência e de susceptibilidade; The immunobiology of infestations with the cattle tick Rhipiceplahus (Boophilus) microplus: comparative immunologic and molecular studies of the tick-host interface in susceptible and resistant bovine hosts.

Franzin, Alessandra Mara
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 31/08/2009 PT
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A pele dos vertebrados é alvo da maioria das 15.000 espécies de artrópodes hematófagos existentes e pouco se sabe sobre as estratégias imunológicas utilizadas pelos hospedeiros para expulsar esse tipo de ectoparasitos. É fato que carrapatos, como artrópodes hematófagos, são capazes também de induzi-las. Entre a grande variedade de hospedeiros, os bovinos, que apresentam fenótipos variáveis de resistência ao Ripicephalus (Boophilus) microplus, constituem o único modelo no qual é possível correlacionar as respostas imunológicas entre os fenótipos contrastantes na mesma espécie hospedeira. Para tal, as populações celulares do infiltrado induzido na pele pelo carrapato foram quantificadas nos bovinos resistentes, Bos taurus indicus e nos suscetíveis, Bos taurus taurus. Como esperado, o carrapato induziu inflamação cutânea local nos bovinos estudados e a composição celular do infiltrado apresentou diferenças que variaram entre os fenótipos contrastantes de infestação. A pele resistente apresentou maior número de basófilos em comparação a pele suscetível infestada pelo carrapato adulto (P < 0,05) o que sugere a participação desse tipo de granulócito na resposta imune, prejudicando a hematofagia do carrapato. Eosinófilos não foram observados na pele naïve...

Um novo gênero e espécie de Baetidae (Ephemeroptera) do Estado de Minas Gerais Sudeste do Brasil

Salles,Frederico F.; Lugo-Ortiz,Carlos R.
Fonte: Fundação Zoobotânica do Rio Grande do Sul Publicador: Fundação Zoobotânica do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2003 PT
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Iguaira gen. nov., type species, I. poranga, sp. nov., based on one nymph from the State of Minas Gerais, Brazil, are proposed. The new taxon is distinguished by the labrum with multiple, unorganized setae dorsally; hypopharynx with three-lobed lingua; cleft mandibular incisors; labium with internally curved paraglossae; labial palps with second segment with strong, apically rounded distomedial process and third segment with truncate medial and apical margins; elongate tarsal claws with minute denticles; and absence of scales and scale bases.

Perianal integument of the nymph and adults stage of Ambloyomma cajennense (Fabricius, 1787) (Acari: Ixodidae): a New Cuticular structure by scanning electron microscopy

Famadas,Kátia Maria; Lanfredi,Reinalda Marisa; Serra-Freire,Nicolau Maués da
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/1994 EN
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Laboratory evaluation of the effects of triflumuron on the development of Rhodnius prolixus nymph

Mello,CB; Mendonça-Lopes,D; Feder,D; Uzeda,CD; Carneiro,RM; Rocha,MA; Gonzalez,MS
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2008 EN
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Studies were carried out to evaluate the efficacy of the growth regulator, triflumuron (TFM) (Starycide® sc 480 Bayer), for disrupting the development of Rhodnius prolixus fifth-instar nymph by oral, topical or continuous treatment. All treatments were able to induce high levels of mortality, delay development and molt inhibition. Oral treatment induced molt inhibition in all insects that survived at doses of 0.25, 0.50 and 5.0 mg/mL of a blood meal. The highest levels of both mortality in 24 h and molt inhibition were always observed after topical treatment. The lowest doses needed to obtain considerable biological effects were always observed after continuous treatment. In this way, the highest levels of mortality within 30 days were detected after continuous treatment, which also induced an extended inter-molting period, a lower number of over-aged nymphs and the highest level of molting in nymphs that survived. Moreover, the effects of TFM on insects were often displayed in a dose response manner. These results indicate that TFM acts as a potent growth inhibitor of R. prolixus nymphs and has the potential to be used in integrated vector control programs against hematophagous triatomine species.

Nymph developmental time and survivorship, adult longevity, reproduction and body weight of Dichelops melacanthus (Dallas) feeding on natural and artificial diets

Panizzi,Antônio R.; Duo,Leandro J. S.; Bortolato,Nágila M.; Siqueira,Fábio
Fonte: Sociedade Brasileira De Entomologia Publicador: Sociedade Brasileira De Entomologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2007 EN
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The biology of nymphs and adults of the neotropical pentatomid, Dichelops melacanthus (Dallas), feeding on the natural foods, soybean, Glycine max (L.) Merrill immature pods, and corn, Zea mays L. immature seeds, and on an artificial dry diet, was studied in the laboratory. Nymph developmental time was shorter on the natural foods (ca. 21-22 days) than on the artificial diet (28 days), and most nymphs reached adulthood on the food plants (55% on soybean and 73% on corn) than on the artificial diet (40%). Fresh body weight at adult emergence was similar and higher for females raised as nymphs on the natural foods, compared to females from nymphs raised on the artificial diet; for males, weights were similar on all foods. Mean (female and male) survivorship up to day 20, decreased from 55% on soybean to 40% on corn, down to 0% on the artificial diet. Total longevity for females was higher on soybean, while for males was similar on all foods. About three times more females oviposited on soybean than on corn, but fecundity/female was similar on both foods. On the artificial diet, only one out of 30 females oviposited. Fresh body weight of adults increased significantly during the first week of adult life, and at the end of the 3rd week...

Nymph and Adult Performance of the Small Green Stink Bug, Piezodorus guildinii (Westwood) on Lanceleaf Crotalaria and Soybean

Panizzi,Antônio Ricardo; Cardoso,Shirlei Regina; Chocorosqui,Viviane Ribeiro
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2002 EN
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Lanceleaf crotalaria, Crotalaria lanceolata E. Mey (Leguminosae) was found hosting the small green stink bug, Piezodorus guildinii (Westwood), in Paraná State, Brazil. In the laboratory, nymphs showed less mortality when fed on immature pods of crotalaria (64%) than when fed on immature pods of soybean, Glycine max (L.) Merrill (88%). From 2nd stadium to adult, nymphs required less time to complete development on crotalaria (mean of females and males = 18.4 days) than on soybean (21.5 days). Fresh body weight at adult emergence was greater on crotalaria (mean of females and males = 51.4 mg) than on soybean (42.2 mg). Adult P. guildinii tended to live longer on crotalaria than on soybean. Mean adult longevity was 34.6 days on crotalaria, and 28.8 days on soybean. However, the reproductive performance of females, although similar on both foods, tended to be greater on soybean. These results indicated that P. guildinii was able to develop and reproduce on the wild host lanceleaf crotalaria. Compared to soybean, this weed plant was more suitable for nymph development, and equally suitable for adult reproduction.

A new species of Crypticerya Cockerell (Hemiptera: Monophlebidae) from Colombia, with a key to species of the tribe iceryini found in South America

Kondo,Takumasa; Unruh,Corinne M
Fonte: Sociedade Entomológica do Brasil Publicador: Sociedade Entomológica do Brasil
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2009 EN
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The adult female and first-instar nymph of a new species of iceryine scale insect, Crypticerya multicicatrices Kondo & Unruh sp. n., are described and illustrated. The new scale insect is polyphagous and was collected on 13 plant species distributed in seven botanical families, including fruit trees of economic importance such as mango and soursop. A taxonomic key to the species of the tribe Iceryini known from South America is provided. Previous records of C. brasiliensis (Hempel) from Colombia are confirmed to be misidentifications of this new species.

Toxicidad de spiromesifen en los estados biológicos de Bactericera cockerelli (Sulc) (Hemiptera: Triozidae)

Tucuch-Haas,Jorge I; Rodríguez-Maciel,J Concepción; Lagunes-Tejeda,Ángel; Silva-Aguayo,Gonzalo; Aguilar-Medel,Sotero; Robles-Bermudez,Agustín; Gonzalez-Camacho,Juan M
Fonte: Sociedade Entomológica do Brasil Publicador: Sociedade Entomológica do Brasil
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2010 ES
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Spiromesifen is an insecticide that inhibits the synthesis of lipids and, in Mexico, its use against the Tomato-Potato Psyllid, Bactericera cockerelli (Sulc), on chili pepper (Capsicum annum), tomato (Lycopersicon sculentum) and potato (Solanum tuberosum) began in 2005; however more information is needed to understand its toxicity on this insect pest. The aim of this research was to determine the toxicity of spiromesifen against each of the biological stages of tomato-potato psyllid, its effect on fertility and viability of eggs deposited by treated females, as well as the female preference to lay eggs on treated and non treated plants. The relative toxicity at 95% mortality (highest LC95 value /LC95 value of the respective biological stage) of spiromesifen in egg, nymph 1, nymph 2, nymph 3, nymph 4, and nymph 5 were 517.5; 31316.2; 2950.1; 315.6; 18.2 and 1-fold, respectively. There were no differences in the toxicity of spiromesifen between adult males and females. The number of laid eggs was reduced as the spiromesifen concentration used to treat female increased and egg hatch was reduced in all tested doses. In the "no choice" test, females deposited 38.6 ± 2.01 eggs by leaf of non treated chili pepper type jalapeño, while in the treated with 360 mg L-1 we observed 0.3 ± 0.08 eggs by leaf. In the "choice" test...

Alcmeone robustus (Hemiptera: Membracidae: Darninae): description of the last-instar nymph and biological notes

Lencioni-Neto,Frederico; Sakakibara,Albino M.
Fonte: Sociedade Brasileira de Zoologia Publicador: Sociedade Brasileira de Zoologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2013 EN
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The last-instar nymph of Alcmeone robustus (Butler, 1877) (Membracidae, Darninae, Darnini) is described and illustrated, and some biological and behavioral notes are provided. The nymphs were observed on Pera sp. (Euphorbiaceae) in the locality of Jacareí, state of São Paulo, Brazil, until they became adults. The newly emerged adults, male and female, are also briefly re-described.

Alarm Pheromones and Chemical Communication in Nymphs of the Tropical Bed Bug Cimex hemipterus (Hemiptera: Cimicidae)

Liedtke, H. Christoph; Åbjörnsson, Kajsa; Harraca, Vincent; Knudsen, Jette T.; Wallin, Erika A.; Hedenström, Erik; Ryne, Camilla
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 30/03/2011 EN
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The recent resurge of bed bug infestations (Cimex spp.; Cimicidae) and their resistance to commonly used pesticides calls for alternative methods of control. Pheromones play an important role in environmentally sustainable methods for the management of many pest insects and may therefore be applicable for the control of bed bugs. The tropical bed bug, Cimex hemipterus, is a temporary ectoparasite on humans and causes severe discomfort. Compared to the common bed bug, Cimex lectularius, little is known about the chemical signalling and pheromone-based behaviour of the tropical species. Here, we show that the antennal morphology and volatile emission of C. hemipterus closely resembles those of C. lectularius and we test their behavioural responses to conspecific odour emissions. Two major volatiles are emitted by male, female and nymph C. hemipterus under stress, (E)-2-hexenal and (E)-2-octenal. Notably, nymph emissions show contrasting ratios of these compounds to adults and are further characterized by the addition of 4-oxo-(E)-2-hexenal and 4-oxo-(E)-2-octenal. The discovery of this nymph pheromone in C. hemipterus is potentially the cause of a repellent effect observed in the bio-tests, where nymph odours induce a significantly stronger repellent reaction in conspecifics than adult odours. Our results suggest that pheromone-based pest control methods developed for C. lectularius could be applicable to C. hemipterus...

Morphology of the first-instar nymph and adult female of Kermes echinatus Balachowsky, with a comparison to K. vermilio Planchon (Hemiptera, Coccoidea, Kermesidae)

Spodek, Malkie; Ben-Dov, Yair
Fonte: Pensoft Publishers Publicador: Pensoft Publishers
Tipo: Artigo de Revista Científica
Publicado em 29/11/2012 EN
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Thefirst-instar nymph and the adult female of Kermes echinatus Balachowsky (Hemiptera, Coccoidea, Kermesidae) are described and illustrated. This species is compared with Kermes vermilio Planchon, a morphologically similar species known in the Palaeractic region.

Cues of Maternal Condition Influence Offspring Selfishness

Wong, Janine W. Y.; Lucas, Christophe; Kölliker, Mathias
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 30/01/2014 EN
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The evolution of parent-offspring communication was mostly studied from the perspective of parents responding to begging signals conveying information about offspring condition. Parents should respond to begging because of the differential fitness returns obtained from their investment in offspring that differ in condition. For analogous reasons, offspring should adjust their behavior to cues/signals of parental condition: parents that differ in condition pay differential costs of care and, hence, should provide different amounts of food. In this study, we experimentally tested in the European earwig (Forficula auricularia) if cues of maternal condition affect offspring behavior in terms of sibling cannibalism. We experimentally manipulated female condition by providing them with different amounts of food, kept nymph condition constant, allowed for nymph exposure to chemical maternal cues over extended time, quantified nymph survival (deaths being due to cannibalism) and extracted and analyzed the females’ cuticular hydrocarbons (CHC). Nymph survival was significantly affected by chemical cues of maternal condition, and this effect depended on the timing of breeding. Cues of poor maternal condition enhanced nymph survival in early broods...

Nymph developmental time and survivorship, adult longevity, reproduction and body weight of Dichelops melacanthus (Dallas) feeding on natural and artificial diets.

PANIZZI, A. R.; DUO, L. J. S.; BORTOLATO, N. M.; SIQUEIRA, F.
Fonte: Revista Brasileira de Entomologia, São Paulo, v. 51, n. 4, p. 484-488, out./dez. 2007. Publicador: Revista Brasileira de Entomologia, São Paulo, v. 51, n. 4, p. 484-488, out./dez. 2007.
Tipo: Artigo em periódico indexado (ALICE)
EN
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ABSTRACT: The biology of nymphs and adults of the neotropical pentatomid, Dichelops melacanthus (Dallas), feeding on the natural foods, soybean, Glycine max (L.) Merrill immature pods, and corn, Zea mays L. immature seeds, and on an artificial dry diet, was studied in the laboratory. Nymph developmental time was shorter on the natural foods (ca. 21-22 days) than on the artificial diet (28 days), and most nymphs reached adulthood on the food plants (55% on soybean and 73% on corn) than on the artificial diet (40%). Fresh body weight at adult emergence was similar and higher for females raised as nymphs on the natural foods, compared to females from nymphs raised on the artificial diet; for males, weights were similar on all foods. Mean (female and male) survivorship up to day 20, decreased from 55% on soybean to 40% on corn, down to 0% on the artificial diet. Total longevity for females was higher on soybean, while for males was similar on all foods. About three times more females oviposited on soybean than on corn, but fecundity/female was similar on both foods. On the artificial diet, only one out of 30 females oviposited. Fresh body weight of adults increased significantly during the first week of adult life, and at the end of the 3rd week...

Mosaic with satyr and nymph

Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Imagem
ENG
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From the House of the Faun

Mosaic with satyr and nymph

Fonte: Universidade Rice Publicador: Universidade Rice
Tipo: Imagem
ENG
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From the House of the Faun

Composition and diversity of Ephemeroptera (Insecta) nymph communities in the middle section of the Jacuí River and some tributaries, southern Brazil; Composição taxonômica e diversidade das comunidades de ninfas de Ephemeroptera (Insecta) do curso médio do Rio Jacuí e afluentes, sul do Brasil

SIEGLOCH, Ana Emilia; FROEHLICH, Claudio Gilberto; KOTZIAN, Carla B.
Fonte: Fundação Zoobotânica do Rio Grande do Sul Publicador: Fundação Zoobotânica do Rio Grande do Sul
Tipo: Artigo de Revista Científica
ENG
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The taxonomic composition and diversity of assemblages of Ephemeroptera nymphs of four lotic environments in the central region of State of Rio Grande do Sul, a subtropical area in southern Brazil, were evaluated. Samplings were done monthly, with a Surber sampler, from June 2001 to May 2002, in the Jacuí River and three of its tributaries. The total number of nymphs collected in the four sampling sites was 11,007 in five families and 19 genera, of these, 11 are new records for the State. The highest diversity occurred in Point 4 (H'=2.41) and the lowest in Point 2 (H'=1.69). Point 4 had the highest environmental stability, conservation of the riparian vegetation and the lowest anthropic impact, while Point 2 presented a large environmental simplification due to a direct anthropic influence (e.g. domestic sewerage, trampling by cattle). The diversity of nymphs observed in the total area is high, compared to the estimated maximum theoretical diversity; a result of the high evenness and richness recorded. Rarefaction curves, calculated for a sample of 1,018 specimens, showed a similar expectation of richness for the four sampling sites. This result seems to be associated with the overall environmental homogeneity of the region caused by long-term alterations (land use and deforestation). In summary...

Life cycle and reproductive parameters of Clerada apicicornis signoret (Hemiptera: Lygaeidae) under laboratory conditions

Cárdenas,Estrella; Morales,Alberto; Torres,Mariela
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2001 EN
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The life cycle of Clerada apicicornis was determined under laboratory conditions. Mean development times in days were: egg 27.2, nymph I 12.5, nymph II 12, nymph III 13.4, nymph IV 16.4, nymph V 26. The life expectancy of adults ranged from 117 to 317 days (mean 196 days). Based on a cohort of 29 females of C. apicicornis, a horizontal life table was constructed. The following predictive parameters were obtained: net rate of reproduction (Ro = 48.31), intrinsic rate of population increase (r m = 0.153), generation time (Tc = 28.20 weeks), and finite rate of population increment (lambda = 1.16). The reproductive value (Vx) for each age class of the cohort females was calculated. The following observed parameters were calculated after mortality in each stage: net rate of reproduction (R'o=13.4), intrinsic rate of population increase (r c' =0.09 ), and finite rate of population increment (lambda' =1.1). The generation time (Tc' =27.4) was estimated using the methods of Laughlin and Bengstron. A vertical life table was elaborated and mortality was described for one generation of the cohort.

Composition and diversity of Ephemeroptera (Insecta) nymph communities in the middle section of the Jacuí River and some tributaries, southern Brazil

Siegloch,Ana Emilia; Froehlich,Claudio Gilberto; Kotzian,Carla B.
Fonte: Fundação Zoobotânica do Rio Grande do Sul Publicador: Fundação Zoobotânica do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2008 EN
Relevância na Pesquisa
26.95%
The taxonomic composition and diversity of assemblages of Ephemeroptera nymphs of four lotic environments in the central region of State of Rio Grande do Sul, a subtropical area in southern Brazil, were evaluated. Samplings were done monthly, with a Surber sampler, from June 2001 to May 2002, in the Jacuí River and three of its tributaries. The total number of nymphs collected in the four sampling sites was 11,007 in five families and 19 genera, of these, 11 are new records for the State. The highest diversity occurred in Point 4 (H'=2.41) and the lowest in Point 2 (H'=1.69). Point 4 had the highest environmental stability, conservation of the riparian vegetation and the lowest anthropic impact, while Point 2 presented a large environmental simplification due to a direct anthropic influence (e.g. domestic sewerage, trampling by cattle). The diversity of nymphs observed in the total area is high, compared to the estimated maximum theoretical diversity; a result of the high evenness and richness recorded. Rarefaction curves, calculated for a sample of 1,018 specimens, showed a similar expectation of richness for the four sampling sites. This result seems to be associated with the overall environmental homogeneity of the region caused by long-term alterations (land use and deforestation). In summary...

Why do mayflies change their gill kinematics as they grow?

Chabreyrie, Rodolphe; Abdelaziz, Khaled; Balaras, Elias; Kiger, Kenneth
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 22/11/2013
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The mayfly nymph breathes under water through an oscillating array of wing-shaped tracheal gills. As the nymph grows, the kinematics of these gills change abruptly from rowing to flapping. The classical fluid dynamics approach to consider the mayfly nymph as a pumping device fails in giving clear reasons to this switch. In order to understand the whys and the hows of this switch between the two distinct kinematics, we analyze the problem under a Lagrangian viewpoint. We consider that a good Lagrangian transport that distributes and spreads water and dissolved oxygen well between and around the gills is the main goal of the gill motion. Using this Lagrangian approach we are able to provide the reason behind the switch from rowing to flapping that the mayfly nymph experiences as it grows. More precisely, recent and powerful tools from this Lagrangian approach are applied to in-sillico mayfly nymph experiments, where body shape, as well as, gill shapes, structures and kinematics are matched to those from in-vivo. In this letter, we show both qualitatively and quantitatively how the change of kinematics enables a better attraction, stirring and confinement of water charged of dissolved oxygen inside the gills area. From the computational velocity field we reveal attracting barriers to transport...

Do omnivorous shrimp influence mayfly nymph life history traits in a tropical island stream?

Macías,Nicholas A.; Colón-Gaud,Checo; Duggins,Jonathan W.; Ramírez,Alonso
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2014 EN
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Interspecific interactions can play an important role in determining habitat selection and resource use between competing species. We examined interactions between an omnivorous shrimp and a grazing mayfly, two co-dominant taxa found in Puerto Rican headwater streams, to assess how predator presence may influence mayfly resource use and instantaneous growth in a tropical rainforest ecosystem. We conducted a series of behavioral and growth experiments to determine the effects of the freshwater shrimp, Xiphocaris elongata, on the growth rate and resource selection of mayfly nymphs in the family Leptophlebiidae. For resource choice assessments, we conducted a series of five day laboratory experiments where mayflies were given access to two resource substrate choices (cobble vs. leaves) in the presence or absence of shrimp. To assess for the effects of shrimp on mayfly fitness, we measured mayfly growth in laboratory aquaria after five days using four treatments (cobble, leaves, cobble + leaves, no resource) in the presence or absence of shrimp. In resource choice experiments, mayflies showed preference for cobble over leaf substrata (p<0.05) regardless of the presence of shrimps, however, the preference for cobble was significantly greater when shrimp were present in the leaf habitat. In growth experiments...