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The Alimentary Canal and Female Reproductive System of a Collembolan, Podura aqauticaPhillips, Richard S. January 1940 (has links)
No description available.
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The Alimentary Canal and Female Reproductive System of a Collembolan, Podura aqauticaPhillips, Richard S. January 1940 (has links)
No description available.
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The reliability of esterase patterns in the determination of species of insects in the order CollembolaHart, John William January 1978 (has links)
Polyacrylamide gel electrophoresis was used to study B-esterases (EC 3.1.1.1) and C-esterases (EC 3.1.1.6) in five species of Collembola--; Folsomia candida, Proisotoma vesiculata, H,ypogastrura denticulata, and two undescribed species of Isotoma,. Ef values were computed for zymograms of 105 individuals and compared both within and among species. Certain bands-three to six in number--predominated on the zymograms of each species. The predominating bands differed among the five species resulting in a unique zymogram for each.It was also found that zymograms of normal and ecomorphic forms of Proisotoma vesiculata were dissimilar. Zymograms of specimens of Folsomia candida with access to food and those without food for 48 and 72 hours were similar. Zymograms from mascerated specimens frozen in buffer were not satisfactory.
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Diversity of the genus Seira (Collembola: Entomobryidae: Seirinae) in the Fynbos and Southern Afrotemperate forestLiu, Wing Pui Amy 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Soil is one of the most complex and understudied terrestrial habitats, and it comprises a wide
range of organisms that affect the functioning of terrestrial ecosystems. Despite the importance
of these below-ground fauna, our understanding of this diversity remains limited, especially in the
Cape Floristic Region (CFR), where higher plants and other more conspicuous invertebrates have
been better represented in the literatures. The main aim of this thesis is to provide the first insights
into the taxonomic, cryptic and spatial diversity of one of the more diverse Collembola genera,
Seira (Collembola: Entomobryidae: Seirinae), in the Fynbos and Southern Afrotemperate forest
habitats of the CFR. Collembola constitute an important component of terrestrial biodiversity and
are essential for ecosystem functioning.
The thesis is divided into two data chapters. The first data chapter examines the mitochondrial
barcoding COI (Cytochrome-c oxidase subunit I) gene of 496 Seira specimens from 41 Fynbos
and forest sites. Discrete Molecular Operational Taxonomic Units (MOTUs) are identified within
Seira. Furthermore, divergence times are estimated and tentatively used to propose historical
triggers for the diversification of Seira. Habitat specificity of Seira is assessed through
phylogenetic reconstruction using Parsimony and Bayesian analyses based on the nucleotide
and amino acid sequences. Genetic divergence indicates that Seira is composed of at least 91
MOTUs, suggesting that morphological taxonomy has vastly under-estimated the richness of this
genus by at least four folds. Most of the MOTUs are highly habitat specific and geographically
localised. The reconstruction of an evolutionary time frame of these lineages reveals several deep
diversifications in the Miocene and a spate of more recent radiations in the Pleistocene and
Holocene. Palaeo-environmental fluctuations and vegetation composition shifts are hypothesised
as having increased the environmental complexity of the region and this may have influenced the
diversification patterns of Seira.
In the second data chapter, the spatial variation of Seira diversity is examined and compared
between and within two major habitat types, Fynbos and forest, across nine study sites. Abiotic
variables were recorded and compared for the investigation of environmental differences among
habitat types. The habitat specificity of Seira is assessed, as well as the relative effects of habitat
types and study sites on assemblage structure. Species richness of Seira is higher in Fynbos than
in forest, and this could be due to the high heterogeneity of niches and resources created by the
steep environmental and floristic gradients in the Fynbos habitats. Perhaps one of the most striking results is the high levels of beta diversity exhibited by Seira. The spatial turnover of the
Seira assemblage is complete or nearly complete among and within habitat types across study
sites within the CFR. Low dispersal abilities and consequently isolated evolutionary histories may
account for the strong assemblage differences within the same habitat type of different study
sites. However, the substantial differences in assemblage composition between adjacent habitat
types in the same site are likely to be the result of the contrasting abiotic conditions exhibited by
the Fynbos and forest habitats, as found by this study.
Overall, the results of this thesis suggest that Seira species richness is much greater than
previously thought. It follows similar diversity patterns to the well-described and hyper-diverse
plant communities of the CFR. Here, for both CFR plants and Seira, the spectacular regional
diversity displayed is not the result of high alpha diversity, but rather of substantial beta diversity.
Because of the high beta diversity and the fact that only two CFR vegetation types were sampled
from a limited number of study sites, I predict that the Seira species richness presented here is
but the tip of the iceberg. / AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar
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Collembola como bioindicadores da qualidade do solo de áreas recuperadas da floresta nacional de Saracá-Taquera, Porto Trombetas, PASerrano, Mariana Botelho 04 June 2007 (has links)
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Previous issue date: 2007-06-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This paper presents the results of the analysis of the ecological structure on
collembolo treated with parameters of richness and diversity, and taxonomic aspect, in
reforestation areas and two primary forests. The main focus of this study was to verify
the recovery of degraded areas and recovered areas over time, comparing the dynamics
which species of Collembola can serve as bioindicators of major changes occurring over
the years of planting.
The comparison in these areas showed that diversity was higher in forests.
However, despite the disturbance, the reforestation show high capacity for colonization
where diversity was not affected. The collembolos are extremely sensitive to changes in
the natural environment. However, the results from this study suggest that the model for
restoration of impacted areas employed by the North River Mining, has led to a positive
process of rehabilitation of these areas, revealed the high diversity of species recorded
in plots reforested with native threes. Moreover, species of Collembolas can be used as
bioindicators of soil quality in these areas. / Neste trabalho são apresentados os resultados da análise da estrutura ecológica
de colêmbolos, tratados através de parâmetros de riqueza e diversidade, bem como
aspecto taxonômico em áreas de reflorestamento e de duas florestas primárias. O foco
principal do trabalho foi verificar a recuperação de áreas degradadas e recuperadas ao
longo do tempo, comparando-se a dinâmica da comunidade de Collembola dessas áreas
com a de uma floresta primária, e assim, determinar espécies de Collembola que possam
servir como bioindicador das principais mudanças que ocorrem ao longo dos anos de
plantio.
A comparação específica nessas áreas de estudo mostrou que a diversidade foi
maior nas florestas. No entanto, apesar da perturbação sofrida, os reflorestamentos
mostram alta capacidade de colonização onde a diversidade não foi afetada. Os
colêmbolos são extremamente sensíveis às mudanças do ambiente natural. Entretanto,
os resultados obtidos neste estudo sugerem que o modelo de restauração das áreas
impactadas empregado pela Mineração Rio do Norte, tem conduzido a um processo de
reabilitação positiva destas áreas, revelado pela alta diversidade de espécies registrada
nas parcelas reflorestadas com árvores nativas. Além disso, espécies de Collembola
podem ser usadas como bioindicadores da qualidade do solo destas áreas.
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Padrões de distribuição da diversidade de Collembola (Arthropoda, Hexapoda) no semiárido ParaíbaLima, Iara Cristina da Silva 28 August 2015 (has links)
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Previous issue date: 2015-08-28 / The Domain Caatinga spans much of the Northeast, the semiarid climate and xerophytic vegetation are striking characteristics of this area. Collembola are found in all zoogeographic regions of the Earth, are non-insect hexapods animals, edaphic and highly dependent on soil moisture. The diversity of this group is closely linked to seasonal and environmental characteristics.The aim of this paper was to verify the Collembola distribution patterns in three areas of environmental protection in the semiarid Paraiba, in the cities of São João do Cariri, São João do Tigre and Santa Teresinha. The search was conducted for two seasonal periods of the year, the dry season and rainy season. In each study area, they were drawn ten plots of 100m² and each plot was traced three distant points among themselves five meters for the removal and measurement of litter and phytosociological survey; in each plot was taken a soil sample. The organisms collected were screened and identified the species level. Absolute and relative abundances were estimated richness, diversity indices, equitability and similarity. To analyze the abundance of the regions between the samples was the Kruskal-Wallis test. The representativeness of the inventory was estimated using species accumulation curve. Within the Protected Areas and between areas: alpha diversity and estimated the beta diversity into two distinct scales was quantified. The diversity indices of Shannon-Wiener, α-Fisher, Margalef, Simpson and Whittaker were used; and the evenness index of Pielou. A cluster analysis was performed to verify the formation of groups among the studied areas. Multivariate as Canonical Correspondence Analysis were used to evaluate the composition of communities and associate this composition habitat. It was collected 6,226 individuals of Collembola during the two periods of collections, represented by 24 species, 17 genera and 9 families; where the dry season (PS) were recorded 50 individuals distributed in 4 families, 7 genera and 7 species During the rainy season (PC) were collected 6,176 individuals in nine families, 17 genera and 24 species. The most representative species were Brachystomella purma and B. agrosa totaling 83.74% of the individuals found. According to statistical analysis, areas of São João do Cariri and Santa Teresinha are most closely related and are more homogeneous than the areas of São João do Tigre. Therefore, any strategies for environmental conservation areas studied should take into account the spatial scales presented in this study, since the change in diversity was highest within each study area. / O Domínio da Caatinga se estende por grande parte da região Nordeste, o clima semiárido e a vegetação xerófila são características marcantes dessa área. Collembola são encontrados em todas as regiões zoogeográficas da Terra, são animais hexápodes não-insetos, edáficos e bastante dependentes da umidade do solo. A diversidade desse grupo está intimamente ligada às características sazonais e ambientais. O objetivo do trabalho foi verificar os padrões de distribuição de Collembola em três regiões de proteção ambiental no semiárido Paraibano, localizadas nas cidades de São João do Cariri, São João do Tigre e Santa Teresinha. A pesquisa foi realizada durante dois períodos estacionais do ano, o período de estiagem e período chuvoso. Em cada área de estudo, foram traçados dez parcelas de 100m² e em cada parcela foi traçados três pontos distantes entre si cinco metros para a retirada e medição do folhiço e levantamento fitossociólogico; em cada parcela foi retirada uma amostra de solo. Os organismos coletados foram triados e identificados a nível de espécies. Foram estimadas abundâncias absoluta e relativa, riqueza, índices de diversidade, equitabilidade e similaridade. Para analisar a abundância entre as amostras das regiões foi utilizado o teste de Kruskal-Wallis. A representatividade do inventário foi estimada por meio de curva de acumulação de espécies. Foi quantificada a diversidade alfa e estimada a diversidade beta em duas escalas distintas: dentro das Áreas de Proteção e entre as Áreas. Foram utilizados os índices de diversidade de Shannon-Wiener, α-Fisher, Margalef, Simpson e Whittaker; e o índice de equitabilidade de Pielou. Uma análise de agrupamento de cluster foi realizada para verificar a formação de grupos entre as áreas estudadas. Técnicas de análise multivariada como Análise de Correspondência Canônica foram usadas para avaliar a composição das comunidades e associar esta composição ao habitat. Foram coletados 6.226 indivíduos de Collembola durante os dois períodos de coletas, representados por 24 espécies, 17 gêneros e 9 famílias; no qual no período seco (PS) foram registrados 50 indivíduos distribuídos em 4 famílias, 7 gêneros e 7 espécies No período chuvoso (PC) foram coletadas 6.176 indivíduos distribuídos em 9 famílias, 17 gêneros e 24 espécies. As espécies mais representativas foram Brachystomella purma e B. agrosa que somaram 83,74% dos indivíduos encontrados. De acordo com as análises estatísticas, as áreas de São João do Cariri e de Santa Teresinha estão mais intimamente relacionadas e são mais homogêneas do que as áreas de São João do Tigre. Sendo assim, quaisquer estratégias voltadas à conservação ambiental das áreas estudadas devem levar em consideração as escalas espaciais apresentadas neste estudo, já que a variação da diversidade foi maior dentro de cada área estudada.
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Características populacionais da classe Collembola (Arthropoda: Hexapoda) no perfil do solo em cincos ambientes da Região de Dourados-MS.Silva, Rosimeire Fernandes da 31 August 2007 (has links)
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Previous issue date: 2007-08-31 / O objetivo deste trabalho foi estudar a composição e a dinâmica das populações dos organismos da Classe Collembola como bioindicadores de impactos ambientais, através da comparação de amostras do solo em ambientes naturais e em agroecossistemas e inferir sobre o seu papel no funcionamento e na sustentabilidade dos sistemas de plantio. O material do estudo foi retirado em cinco ambientes distintos localizados na Fazenda Experimental da Universidade Federal da Grande Dourados (UFGD) e Mata do Azulão (Fazenda Coqueiro): plantio direto irrigado (PDI), plantio direto de sequeiro (PDS), plantio convencional irrigado (PCI) plantio convencional de sequeiro (PCS), e ambiente natural (mata), em cinco profundidades do perfil do solo para cada local amostrado no município de Dourados-MS, no período de agosto à dezembro de 2006. Foram obtidos 108 indivíduos divididos em 6 famílias. O ambiente natural registrou um efeito decrescente em número de indivíduos da primeira para a última camada amostrada. Em PDI e ambiente natural ocorreu a maior média de organismos, seguidos por PDS. Os representantes das famílias Isotomidae e Entomobryidae foram encontrados em maior quantidade nestes sistemas. A Família Isotomidae teve um aumento no número de indivíduos encontrados da primeira para a última época amostrada.
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Structure and functions of the ventral tube of the clover springtail Sminthurus viridis (Collembola Sminthuridae)Chen, C-G., Chen, T., Hua, B-Z., Wan, Tao Ruan 29 January 2019 (has links)
Yes / Springtails (Collembola) are unique in Hexapoda for bearing a ventral tube (collophore) on the first abdominal segment. Although numerous studies have been conducted on the functions of the ventral tube, its fine structure has not been thoroughly elucidated to date. In this paper, we observed the jumping behavior of the clover springtail Sminthurus viridis (Linnaeus, 1758) and dissected the ventral tube using light microscopy to elucidate the fine structure and the possible function of the ventral tube. The results show that a pair of eversible vesicles can be extended from the apical opening of the ventral tube. The eversible vesicles are furnished with numerous small papillae, and can be divided into a basal part and a distal part. The eversible vesicles have a central lumen connected to the tiny papillae and leading to the body cavity. The eversible vesicles can reach any part of the body, and may serve as following functions: (a) absorbing moisture; (b) uptaking water; (c) cleaning the body surface; and (d) fastening the body on a smooth surface.
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Diversidade de collembola (Arthropoda, Hexapoda) do arquipélago Fernando de Noronha, BrasilLima, Estevam Cipriano Araújo de 20 February 2014 (has links)
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Previous issue date: 2014-02-20 / The terrestrial fauna on oceanic islands is highly vulnerability and diversity
particular due to the geographical limited and unique space. Conservation Strategies
of island must be strict to ensure the maintenance of diversity. The recognition of
distribution patterns of diversity is important to determine the appropriate spatial
scales for the development of conservation strategies biogeographic. This work, by
partitioning the diversity of Collembola in Oceanic Islands of the Archipelago
Fernando de Noronha, we present the distribution pattern the diversity of arthropods
and also described a new species of Collembola endemic to this island environment.
This work was structured in three chapters. In the first we present the state of the art,
the objectives (general and specific), hypothesis, inquiry and characterization of the
study area. The remaining chapters were developed in article format, respecting the
proposed by the respective magazines format. The second chapter presents a study
on the spatial distribution of Collembola, which determine the appropriate scale for
the conservation of the Archipelago Fernando de Noronha and will be submitted for
Diversity and Distributions ( IF 6.122 ) magazine and third present the first species of
collembola endemic and restricted the sandy strand of the Archipelago Fernando de
Noronha published in The Florida Entomologist (IF 1.163 ) in December 2013
(volume 96 , pages 1579-1587) titled " A New Species of Isotogastrura (Collembola :
Isotogastruridae) from Northeastern Brazil " (PALACIOS - VARGAS et al., 2013) . / A fauna terrestre em ilhas oceânicas apresenta alta vulnerabilidade e
diversidade particular, devido ao espaço geográfico restrito e único. As estratégias
de conservação dos ambientes insulares devem ser rigorosas para garantir a
manutenção da diversidade. O reconhecimento dos padrões de distribuição da
diversidade é importante para determinar as escalas espaciais apropriadas para o
desenvolvimento de estratégias de conservação biogeográfica. No presente
trabalho, através do particionamento da diversidade de Collembola em Ilhas
Oceânicas do Arquipélago Fernando de Noronha, apresentamos o padrão de
distribuição da diversidade destes artrópodes e também descrevemos uma nova
espécie de Collembola endêmica deste ambiente insular. Este trabalho foi
estruturado em três capítulos. No primeiro apresentamos o estado da arte, os
objetivos (gerais e específicos), hipótese, pergunta e a caracterização da área de
estudo. Os demais capítulos foram desenvolvidos em formato de artigo, respeitando
o formato proposto pelas respectivas revistas. O segundo capítulo traz um estudo
sobre a distribuição espacial de Collembola, onde determinamos a escala apropriada
para a conservação do Arquipélago Fernando de Noronha e será submetido à
revista Diversity and Distributions (IF 6.122) e no terceiro apresentamos a primeira
espécie de collembola endêmica e restrita ao cordão arenoso do Arquipélago
Fernando de Noronha publicado na revista The Florida Entomologist (IF 1.163) em
dezembro de 2013 (volume 96, páginas 1579-1587) intitulado A New Species Of
Isotogastrura (Collembola: Isotogastruridae) From Northeastern Brazil (PALACIOSVARGAS
et
al.,
2013).
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Comparative phylogeographic patterns among selected indigenous and introduced Collembola on Marion IslandMyburgh, Marike 04 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: Marion Island is situated approximately 2600 km southeast of Cape Town and is the larger of
the two islands that comprise the Prince Edward Island group. During past glaciation events,
Marion was partially covered by ice with fauna and flora confined to isolated refugia across
the island. As a result of these long-term isolation events, it is postulated that species
predating these glaciation events might show geographic partitioning of genetic variation.
Subsequently, the majority of Southern Oceanic islands have a history of sealing activities
with vessels frequenting various islands in their hunt for seals. These combined visits to
several islands could have facilitated the introduction of alien species, or the reintroduction of
species already present on islands. These incidents, combined with more recent scientific
voyages, have led to the establishment of several exotic species on Marion Island. Two
indigenous Collembola species (Cryptopygus antarcticus (Willem, 1901) and Tullbergia
bisetosa (Börner, 1903)) were chosen as model species to investigate the possible effects of
glaciation on the spatial distribution of genetic variation on indigenous species. Given the
negative impact that alien taxa have on indigenous species and ecosystems, the
phylogeographic population structure of the recently introduced Isotomurus cf. palustris
(Müller, 1876) was determined and compared to those described for the two indigenous
species. To address these questions, two mitochondrial DNA genes were targeted:
cytochrome oxidase subunit I (COI) and cytochrome oxidase subunit II (COII). These genes
were sequenced (GENBANK accession numbers DQ147289-DQ147558) and analysed using,
amongst others, AMOVA (Analysis of Molecular Variance), SAMOVA (Spatial Analysis of
Molecular Variance) and NCA (Nested Clade Analysis). As expected, the two indigenous
species showed distinct signs of population expansion, whilst the recently introduced species
exhibits little genetic variance across its range. The life histories of species have an influence
on their resultant genetic signature; therefore life history parameters were incorporated to
explain differences in the phylogeographic patterns observed for these three species. / AFRIKAANSE OPSOMMING: Marion Eiland is die groter van twee eilande wat die Prins Edward eilandgroep vorm,
ongeveer 2600 km suid-oos vanaf Kaapstad. Gedurende glasiasie episodes in die verlede, was
Marion gedeeltelik met ys bedek en fauna en flora was geisoleer in klein gedeeltes van die
eiland wat beskut was. As gevolg van hierdie langtermyn isolasie word daar voorgestel dat
spesies wat op die eiland was voor hierdie gebeurtenisse plaasgevind het, ‘n geografiese
verdeling van genetiese variasie sal toon. Sedertdien het die meerderheid van die eilande in
die Suidelike Oseaan ook ‘n geskiedenis van skepe wat op een of meer van die eilande
aangedoen het in die jag op robbe. Hierdie besoeke deur die robjagters aan die eilande het
meegebring dat daar eksotiese spesies op die eiland aangekom het of dat spesies wat reeds op
die eiland voorgekom het, opnuut daar geland het. Hierdie, tesame met die onlangse
wetenskaplike reise na Marion Eiland, het daartoe gelei dat baie eksotiese spesies ingevoer is
na die eiland. Twee inheemse spesies, naamlik Cryptopygus antarcticus (Willem, 1901) en
Tullbergia bisetosa (Börner, 1903) is gekies om as model spesies te dien om die moontlike
gevolge van glasiasie op die geografiese verspreiding van genetiese variasie te toets. In ag
geneem die moontlike negatiewe impak wat eksotiese spesies op die inheemse spesies mag
hê, is die filogeografie van ‘n uitheemse spesie, Isotomurus cf. palustris (Müller, 1876) ook
bepaal en vergelyk met díe van die bogenoemde inheemse spesies. Dit is gedoen deur twee
gene, sitokroom oksidase I (COI) en sitokroom oksidase II (COII) te analiseer. Hierdie gene
se basispaarvolgordes is bepaal (GENBANK toetreenommers DQ147289-DQ147558), en
hulle is ge-analiseer deur gebruik te maak van AMOVA (Analise van Molekulêre Variasie),
SAMOVA (Ruimtelike Analises van Molekulêre Variasie) en NCA
(geseteldegroepsanalises). Net soos verwag, het die twee inheemse spesies albei duidelike
tekens getoon van ‘n bevolkingstoename terwyl die uitheemse spesie amper geen variasie oor
sy verspreidingsgebied getoon het nie. Die lewensstyle van spesies het ‘n beduidende invloed
op hulle genetiese bevolkingstruktuur. As sulks is díe in ag geneem om die verskille tussen
hulle genetiese strukture te verduidelik.
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