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1

Doumeng, Valérie. "L’état civil des populations marginales de la Guyane française". Bulletin de la Société d'Histoire de la Guadeloupe, n.º 146-147 (2007): 149. http://dx.doi.org/10.7202/1040656ar.

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2

Raoulx, Benoît. "La pratique de l'espace urbain des populations marginales : l'exemple des « binners » de Vancouver". Espace, populations, sociétés 17, n.º 2 (1999): 353–57. http://dx.doi.org/10.3406/espos.1999.1898.

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3

de Robert, Pascale. "Le café dans la montagne, quels enjeux pour les populations marginales non productrices ?" Caravelle 61, n.º 1 (1993): 165–76. http://dx.doi.org/10.3406/carav.1993.2556.

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4

Trenta, Arnaud. "Argentine. Le développement productif contre l’environnement ?" Chronique Internationale de l'IRES N° 184, n.º 4 (19 de diciembre de 2023): 107–22. http://dx.doi.org/10.3917/chii.184.0107.

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En Argentine, la préoccupation pour le développement du système productif relègue au second plan la question environnementale. Le modèle extractiviste-exportateur fondé sur l’exploitation des ressources naturelles à grande échelle provoque des dégâts environnementaux majeurs et des conflits avec les populations autochtones. Les organisations syndicales dominantes soutiennent ce modèle de développement économique, d’autres plus marginales défendent la cause environnementale en s’alliant avec les mouvements sociaux autochtones.
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5

Meister, Albert. "La formation des adultes et le développement". Débat, n.º 6 (1 de febrero de 2016): 141–49. http://dx.doi.org/10.7202/1034977ar.

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S’agissant des pays en voie de développement, lorsqu’on parle de formation des adultes, c’est essentiellement l’alphabétisation fonctionnelle (liée au travail) et l’enseignement des techniques élémentaires qu’on évoque. L’échec reconnu des campagnes d’alphabétisation doit conduire à remettre en cause plusieurs vérités non démontrées sur lesquelles elles reposaient, telles la prétendue soif d’apprendre, la volonté de changement, la transformation des attitudes face au travail et au développement, l’évolution vers une vie plus démocratique, la réduction des inégalités sociales, la diminution de la violence. Que va-t-il advenir des programmes de formation des adultes en période de restriction des budgets ? N’est-on pas en train de considérer que les populations marginales n’ont d’autre fonction historique que de contribuer à créer la plus-value indispensable au développement et à l’amélioration des niveaux de vie de la population intégrée ?
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6

Fierro Herrera, Claudia Yanet, Josefina Sarahi Candia Arredondo, Sandra Cristina Pillon, María Magdalena Alonso Castillo y Francisco Rafael Guzmán Facundo. "Percepción de riesgo y religiosidad en el consumo de marihuana en adolescentes de zonas marginales". Horizonte Sanitario 22, n.º 2 (29 de abril de 2023): 255–61. http://dx.doi.org/10.19136/hs.a22n2.5427.

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Objective: To describe the effect of the perception of risk and religiosity on the consumption of marijuana in adolescents from marginal areas of the State of Chihuahua, Chihuahua. Materials and methods: Study descriptive correlational design. The sampling was simple random probabilistic. The final sample consisted of 248 adolescents between the ages of 12 and 17 from marginal areas of Chihuahua. A personal data card, religiosity inventory and the risk perception scale were used. Results: 59.3% of the adolescents interviewed were men, of whom 59.7% said they were Catholic and 23% Christian. 16.1% indicated marijuana use at some time in their life, and 6.5% in the last year. The logistic regression model of the religiosity and risk perception variables showed an explained variance of 19% for marijuana use at some time in life, highlighting that the higher the risk perception (β=-0.032, p<.001) and a higher religiosity index (β=-0.023, p<0.001), the lower the probability of marijuana use. Conclusions: Risk perception and religiosity in adolescents from marginal areas show to be protective factors for marijuana use. These results should be analyzed in greater depth to be considered in prevention programs for drug use in marginal populations. Keywords: Adolescence; Marihuana; Religion; Perception; Risk.
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7

Mével, Adrien. "La définition de la participation des polices municipales françaises à la production locale de l’ordre". Revue française d'administration publique 185, n.º 1 (23 de septiembre de 2024): 109–32. http://dx.doi.org/10.3917/rfap.185.0111.

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L’activité des polices municipales des trois grandes villes françaises étudiées dans l’article s’organise, sous l’effet de la commande politique, autour de deux missions centrales : la contention de l’économie illicite et le contrôle des populations marginales ; dans le même temps, le temps consacré à la gestion des véhicules se réduit par délégation aux agents de surveillance de la voie publique (ASVP). Des différences subsistent néanmoins entre villes sur le plan de la recherche du flagrant délit et de la réponse aux appels 17. Les caractéristiques organisationnelles de chaque police municipale délimitent sa capacité à investir ces tâches, mais elles n’expliquent pas à elles seules les écarts constatés : la police nationale joue aussi un rôle de définition du mandat de la police municipale, selon qu’elle lui délègue des missions ou la tient à distance.
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8

ΤΣΙΜΠΙΡΙΔΟΥ, ΦΩΤΕΙΝΗ. "«ΜΑΣ ΛΕΝΕ ΠΟΜΑΚΟΥΣ!» ΚΛΗΡΟΝΟΜΙΕΣ ΚΑΙ ΠΟΛΙΤΙΚΕΣ, ΚΑΤΑΣΚΕΥΕΣ ΚΑΙ ΒΙΩΜΑΤΑ ΣΕ ΜΕΙΟΝΟΤΙΚΕΣ, ΠΕΡΙΘΩΡΙΑΚΕΣ ΤΑΥΤΟΤΗΤΕΣ". Μνήμων 21 (1 de enero de 1999): 163. http://dx.doi.org/10.12681/mnimon.789.

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<p>Fotini Tsibiridou, «On nous appelle Pomah). Héritages et politiques, constructionset expériences des identités minoritaires et marginales</p><p>Ce texte puise ses données et ses arguments d'une «ethnographie» quiest en voie de publication en France. La dernière traite des constructionssocioculturelles des identités dans la montagne du Rhodope de la Thracegrecque. Elle cherche à relever les manières avec lesquelles les identitésculturelles, sexuelles et sociales dont la plus récente, l'identité ethnique,sont vécues par les sujets. La montagne du Rhodope est habitée par despopulations musulmanes slavophones qui sont marginales par rapport à la majorité de la «minorité musulmane» de la Thrace grecque, à partirde 1923.Dans le texte présent, la problématique anthropologique (théorie,terrain, ethnographe) est d'abord exposée de manière raccourcie; par lasuite, ce texte est centré sur le passé de ces populations, ou, mieux, surle traitement du passé et de son héritage sur le présent.Dans ce cadre, ambiguïtés, ambivalences, états conflictuels et réticencessemblent définir des identités culturelles et sociales différentessous le poids des macro- et micro-politiques et des conditions sociohistoriquesprécises. Or, toutes ces sociétés montagnardes avaient unpoint au moins en commun: l'héritage du passé d'une identificationcommune hétérodéfinie par les groupes voisins, stigmatisée par des attributsnégatifs comme «différent» et «inférieur», «minoritaire» et «marginal», «infidèle» et «peu fiable».Ces discriminations en héritage sont littéralement «incorporées» dansles attitudes quotidiennes et rituelles des sujets sociaux, comme la recherchesur le terrain l'a constaté; leurs pratiques comprennent, entreautres, l'adoption du silence, l'hésitation de s'extrérioriser et de s'exposer, l'immobilisation devant la présence de tout pouvoir, la symbolisationdans la situation suspendue, le passage dans la marge de la modernité.</p>
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9

Morin, Hubert. "Importance et évolution des épidémies de la tordeuse des bourgeons de l’épinette dans l’est du Canada : l’apport de la dendrochronologie". Géographie physique et Quaternaire 52, n.º 2 (2 de octubre de 2002): 237–44. http://dx.doi.org/10.7202/004856ar.

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Résumé La compilation de toutes les chronologies publiées sur les épidémies de la tordeuse des bourgeons de l'épinette établies à partir de la largeur des cernes de croissance des arbres hôtes a été utilisée pour étudier l'évolution spatiale et temporelle des épidémies survenues au cours du XX e siècle dans l'est de l'Amérique du Nord et particulièrement dans les régions nordiques. L'étude inclue 19 chronologies comprenant 1 257 arbres échantillonnés. Les données sont nombreuses pour certaines régions du Québec mais fragmentaires dans d'autres régions comme l'est et le centre de l'Ontario. On observe un remarquable synchronisme des plus faibles croissances radiales associées à la défoliation entre les différentes régions représentées pour les trois épidémies enregistrées au XX e siècle. La plus faible croissance radiale a été atteinte dans la majorité des régions vers 1914 pour la première épidémie du XX e siècle, entre 1948 et 1952 pour la deuxième et entre 1977 et 1979 pour la troisième. L'analyse des chronologies existantes ne montre pas une expansion des épidémies des régions méridionales vers les régions plus nordiques à moins forte proportion de sapin. Les chronologies du sud du Québec sont synchrones avec celles de la réserve des Laurentides et du nord du Saguenay - Lac Saint-Jean pour les trois épidémies, jusqu'au 50 e parallèle où les populations de sapin sont marginales. Il y a un léger décalage vers l'est pour la première épidémie, dans le Bas-Saint-Laurent et en Gaspésie. Les résultats des analyses dendrochronologiques présentées appuient l'hypothèse selon laquelle la dynamique des populations de tbe dans les forêts boréales nordiques du domaine de la pessière noire ne serait pas fondée sur un débordement des populations plus méridionales en période d'épidémies graves mais résulterait d'une augmentation relativement synchrone de populations présentes à l'état endémique.
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10

Albergel, J., S. Nasri y J. M. Lamachère. "Programme de recherche sur les lacs collinaires dans les zones semi-arides du pourtour méditerranéen". Revue des sciences de l'eau 17, n.º 2 (12 de abril de 2005): 133–51. http://dx.doi.org/10.7202/705526ar.

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Un lac collinaire est une retenue créée par un petit barrage en terre. Les lacs collinaires contiennent quelques dizaines de milliers à 1 million de m3 d'eau recueillie sur des bassins versants d'une superficie de quelques hectares à quelques km2. Ils s'intègrent de façon naturelle dans le paysage en ne créant pas de nuisance particulière. Ils sont aptes à réguler les flux hydriques et donc susceptibles de maintenir les populations en place en leur assurant de réelles possibilités de développement. HYDROMED est un programme de recherche mené dans quatre pays (Liban, Maroc, Syrie et Tunisie), engagés dans une politique de construction de petits barrages en complément des réalisations de grande hydraulique. L'objectif du projet HYDROMED a été d'étudier l'aménagement " lac collinaire" et ses impacts sur l'environnement proche et sur les sociétés rurales riveraines. Outre les opérations de coordination et de formation, quatre opérations de recherches ont été menées - Synthèse des travaux existants et choix des sites pour les expérimentations, - Eau - Sol - Environnement, - Agronomie - Impacts sociaux et économiques, - Pérennité du lac collinaire et son intégration dans le développement durable des régions marginales.
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11

Bernardot, Marc. "Chronique d'une institution : la "sonacotra" (1956-1976)". Sociétés contemporaines 33-34, n.º 1-2 (1 de julio de 1999): 39–58. http://dx.doi.org/10.3917/soco.p1999.33n1.0039.

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Résumé RÉSUMÉ: Pendant la guerre d’Algérie et dans un contexte de crise du logement, le ministère de l’Intérieur crée une société de logement originale: la Sonacotra (Société nationale de construction pour les travailleurs algériens). Ce programme de construction spécialisé consiste en l’érection et la gestion de logements pour les travailleurs invités célibataires en France. Sous la pression des bidonvilles autour de Paris, Lyon et Marseille, la Sonacotra applique cette politique de lutte contre l’habitat insalubre. Dans ces espaces sont concentrés des «Nords-Africains». La résorption des taudis et des habitats auto-construits est l’occasion de sélectionner des populations dans le processus de restructuration urbaine. Les célibataires étrangers sont hébergés dans des hôtels spéciaux et les familles nords-africaines dans des cités d’urgences temporaires en périphérie des villes. En revanche les familles françaises sont logées dans des programmes sociaux dans les aires rénovées. Cette politique permet à la Sonacotra de mener des programmes prestigieux de rénovation et d’aménagement urbain conduisant à la disparition des formes de logements marginales comme les meublés et les squatts. Mais la conséquence de cette politique de rénovation est la concentration et la stigmatisation des résidents des hôtels et des cités.
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12

Smyth, Gemma. "Strengthening Social Justice in Informal Dispute Resolution Processes Through Cultural Competence". Windsor Yearbook of Access to Justice 27, n.º 1 (1 de febrero de 2009): 112. http://dx.doi.org/10.22329/wyaj.v27i1.4565.

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Professor Voyvodic’s call for cultural competence as an ethical requirement challenges perceptions of the legal profession as inherently and necessarily morally neutral. While lawyers wrestle with the boundaries of ethical mandates, alternative dispute resolution practitioners have adopted their own codes of ethics following very much in the path of the law. Although expanding dispute resolution options for disputants, many theorists have warned of the potential of informalism to undermine natural justice principals. I will argue that the choice to omit any explicit commitment to a “social justice ethic” leaves the practice of ADR vulnerable to these decades-old arguments that informalism erodes protections for marginalized populations. As such, I will argue that mediators must call for an explicit social justice mandate in their codes of conduct, training and practices to cement the place of informal processes as equitable – not just efficient – options for settlement. In doing so, informal processes, particularly mediation, may increase discourse in civil society about human rights, thus strengthening their congruence with lived realities of citizens.L’appel que fait la professeure Voyvodic en faveur de compétence culturelle comme exigence éthique lance un défi aux avocats de considérer la compétence culturelle comme étant centrale à leur rôle professionnel, et conteste les suppositions de neutralité morale qui sont centrales à la pratique juridique traditionnelle. Pendant que les avocats débattent les frontières de mandats éthiques, ceux et celles qui s’intéressent au règlement extrajudiciaire de conflits (REC) ont adopté leurs propres codes de déontologie qui, suivant de près les sentiers du droit, omettent généralement toute mention de justice sociale, de compétence culturelle ou de droits de la personne. À mon avis, le choix d’omettre un engagement explicite envers la compétence culturelle et la justice sociale expose la pratique du REC aux arguments vieux de plusieurs décennies que l’informalisme ronge les protections pour les populations marginales. Ainsi je soutiendrai que les médiateurs doivent exiger un mandat explicite de justice sociale dans leurs codes de déontologie, leur formation et leurs pratiques afin de cimenter la place des processus informels comme alternatives équitables – et non seulement efficaces – de règlement de conflits. De cette façon, les processus informels, surtout la médiation, pourraient devenir des lieux importants de discours au sujet des droits de la personne qui reflètent mieux les défis envisagés par les membres les plus vulnérables de la société.
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13

Jarosz, A. M. y J. J. Burdon. "Host-pathogen interactions in natural populations of Linum marginale and Melampsora lini". Oecologia 89, n.º 1 (enero de 1992): 53–61. http://dx.doi.org/10.1007/bf00319015.

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14

Lazarenko, E. V., L. I. Shaposhnikova y N. V. Yermolova. "SEASONAL CHANGES IN THE IMAGO PHYSIOLOGICAL AGE IN THE DERMACENTOR MARGINATUS (ACARI, IXODIDAE) NATURAL POPULATION IN THE CENTRAL CISCAUCASIA". Medical Parasitology and Parasitic Diseases, n.º 1 (2021): 3–8. http://dx.doi.org/10.33092/0025-8326mp2021.1.3-8.

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The article discusses the seasonal changes in the age composition (physiological age) of imagoes of Dermacentor marginatus ticks natural populations. To determine the physiological age, we used 1477 hungry imagoes of D. marginatus, collected on a flannel flag, under the conditions of a stationary observation site. During the entire observation period, ticks of the third physiological age prevailed. Wintering imagoes include ticks of third and fourth physiological ages. In April, at the peak of activity, the nucleus of the population is made up of ticks of second and third physiological age. A small part of the population during this period is made up of individuals of fourth physiological age. In May, the percentage of recently activated individuals decreases markedly. In collections of this period, strongly emaciated individuals of fourth physiological age predominate. The summer population of ticks is represented by individuals of the third and fourth physiological ages. Their share is over 90%. Individuals of second physiological age were found by us only in early June and late August. In autumn, the bulk of the population is also represented by individuals of third and fourth physiological ages. Keywords: imagoes, Ixodes ticks, Dermacentor marginatus, Central Ciscaucasia, physiological age, age composition
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15

Kushel, Margot B., Judith A. Hahn, Jennifer L. Evans, David R. Bangsberg y Andrew R. Moss. "Revolving Doors: Imprisonment Among the Homeless and Marginally Housed Population". American Journal of Public Health 95, n.º 10 (octubre de 2005): 1747–52. http://dx.doi.org/10.2105/ajph.2005.065094.

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16

Shoaib, Muhammad. "Prevalence and Molecular Characterization of Anaplasma marginale in Cattle Population of Khyber Pakhtunkhwa Province, Pakistan". International Journal of Agriculture and Biology 25, n.º 05 (1 de mayo de 2021): 1016–23. http://dx.doi.org/10.17957/ijab/15.1759.

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Anaplasmosis is a hemo-rickettsial disease of cattle and is most prevalent in tropical and subtropical regions of the world including Pakistan. This disease has been placed as one of the most economically important haemoparasitic diseases. The aim of the current study was to determine the molecular characterization and to assess the prevalence of Anaplasma marginale (A. marginale) infection in cattle and associated risk factors in three districts of Khyber Pakhtunkhwa (KP) province of Pakistan viz., Mardan, Kohat and Swat. The blood samples were collected conveniently from 434 tick-infested animals keeping the aseptic measures. A. marginale was identified from blood samples by microscopy and PCR. Sequencing and phylogenetic analysis of the sequenced isolates of this study showed close sequence similarity with the reported strains of USA, Thailand, Uganda, Uruguay, Zimbabwe, Philippines and China. Moreover, multiple sequence alignment of the 16S ribosomal RNA gene sequences of 5 different clones of the A. marginale depicts substantial variation in the genotypes of A. marginale found in different locations of KP. The prevalence of A. marginale infection was non-significantly associated (P > 0.05) with districts, season, breed, age and sex of cattle. The highest prevalence of A. marginale infection was recorded in district Swat (20.30%) followed by Kohat (16.81%) and Mardan (15.00%) districts of KP. The prevalence of infection was highest in exotic breeds and their crosses, adults and female cattle. 10.70, 16.11, 46.70 and 26.70% were the prevalence of infection recorded for winter, spring, summer and autumn season, respectively. This study concludes that A. marginale infection is dominant in district Swat followed by Kohat and Mardan districts of KP province of Pakistan, respectively. © 2021 Friends Science Publishers
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17

Landau, Philippe-Efraïm. "Nation marginale, population dangereuse ? Considérations sur les Juifs à Paris sous Louis XV". Archives Juives 44, n.º 2 (2011): 26. http://dx.doi.org/10.3917/aj.442.0026.

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18

Burdon, J. J. y A. M. Jarosz. "Host-Pathogen Interactions in Natural Populations of Linum marginale and Melampsora lini: I. Patterns of Resistance and Racial Variation in a Large Host Population". Evolution 45, n.º 1 (febrero de 1991): 205. http://dx.doi.org/10.2307/2409494.

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19

Thavornkanlapachai, Rujiporn, Margaret Byrne, Colin J. Yates y Philip G. Ladd. "Degree of fragmentation and population size do not adversely affect reproductive success of a rare shrub species, Banksia nivea (Proteaceae), in a naturally fragmented community". Botanical Journal of the Linnean Society 191, n.º 2 (6 de septiembre de 2019): 261–73. http://dx.doi.org/10.1093/botlinnean/boz041.

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Abstract Fragmentation of plant communities is generally considered to be detrimental to the survival of the constituent species, especially those that are rare. We investigated the effects of fragmentation on reproductive biology in nine populations of the rare taxon Banksia nivea subsp. uliginosa, differing in size and habitat context. Small mammals were the main pollinator, with lower contributions from honeybees and birds (honeyeaters). There was no significant relationship between population size, fruit set and seed germinability. Fruit set was marginally highest (25.5 ± 3.4) in medium size populations and was variable over years. Lower fruit set (1.0 ± 0.6) in the smallest population may be due to inbreeding depression or lack of pollinators in a degraded habitat, but low fruit set was also observed in the largest population despite high levels of gene flow, possibly due to low pollinator visitation rate in a low-density population. Seeds from all populations had high germination success (>93.4%). Predation occurred in up to 56% of fruit and increased with increasing population size, but was not significantly different between populations of different size. Our study provided evidence that the reproductive output in species in a naturally fragmented landscape system may be resilient to reduced population size and other influences of anthropogenic fragmentation.
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20

Vaini, Jussara Oliveira, Rodrigo Rodrigues Domingues, Bruno Lopes da Silva Ferrette, Eric M. Hallerman, Kenneth Gabriel Mota, João Pedro Barreiros y Alexandre Wagner Silva Hilsdorf. "Global population genetic structure of the sequential hermaphrodite, dusky grouper ( Epinephelus marginatus )". Aquatic Conservation: Marine and Freshwater Ecosystems 31, n.º 8 (14 de mayo de 2021): 2119–30. http://dx.doi.org/10.1002/aqc.3608.

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21

Maggio, Teresa, Franco Andaloro y Marco Arculeo. "Genetic population structure ofEpinephelus marginatus(Pisces, Serranidae) revealed by two molecular markers". Italian Journal of Zoology 73, n.º 3 (septiembre de 2006): 275–83. http://dx.doi.org/10.1080/11250000600804599.

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22

Barbet, Anthony F., Anna Lundgren, Jooyoung Yi, Fred R. Rurangirwa y Guy H. Palmer. "Antigenic Variation of Anaplasma marginale by Expression of MSP2 Mosaics". Infection and Immunity 68, n.º 11 (1 de noviembre de 2000): 6133–38. http://dx.doi.org/10.1128/iai.68.11.6133-6138.2000.

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ABSTRACT Anaplasma marginale is a tick-borne pathogen, one of several closely related ehrlichial organisms that cause disease in animals and humans. These Ehrlichia species have complex life cycles that require, in addition to replication and development within the tick vector, evasion of the immune system in order to persist in the mammalian reservoir host. This complexity requires efficient use of the small ehrlichial genome. A. marginaleand related ehrlichiae express immunoprotective, variable outer membrane proteins that have similar structures and are encoded by polymorphic multigene families. We show here that the major outer membrane protein of A. marginale, MSP2, is encoded on a polycistronic mRNA. The genomic expression site for this mRNA is polymorphic and encodes numerous amino acid sequence variants in bloodstream populations of A. marginale. A potential mechanism for persistence is segmental gene conversion of the expression site to link hypervariable msp2 sequences to the promoter and polycistron.
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23

Smith, Curtis y Ernesto Castañeda-Tinoco. "Improving Homeless Point-In-Time Counts: Uncovering the Marginally Housed". Social Currents 6, n.º 2 (23 de noviembre de 2018): 91–104. http://dx.doi.org/10.1177/2329496518812451.

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This article discusses improvements made to the methodology of the Housing and Urban Development (HUD) point-in-time (PIT) homeless census. HUD’s PIT results are presented to Congress as official data for policy consideration. Yet, PIT methodology focuses on visible street homeless individuals and those in shelters while neglecting the “marginally housed” or less visible homeless who live in automobiles or temporarily stay with friends and extended family. Being a hidden population, the marginally housed has been a traditionally difficult population to study. We replicated HUD’s PIT count but additionally targeted the marginally housed to improve traditional methods of counting the homeless. We improve the PIT count in two ways: (1) by extensively training counters, and (2) by using the personal networks of hundreds of counters to seek out the marginally housed. Student researchers from a local university located 333 more homeless individuals than the local PIT, of which 153 were marginally housed. We do not claim this to be an exhaustive count of all the marginally housed in the region, but it is an initial step in developing methodologies to include this hidden population when calculating the total homeless population. This approach can also improve traditional homeless counts in other cities.
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24

Bergenius, Mikaela A. J., Anna Gårdmark, Didzis Ustups, Olavi Kaljuste y Telja Aho. "Fishing or the environment – what regulates recruitment of an exploited marginal vendace (Coregonus albula (L.)) population?" Advances in Limnology 64 (30 de octubre de 2013): 57–70. http://dx.doi.org/10.1127/1612-166x/2013/0064-0029.

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25

Salsabilla, Vinka, Sudarjat Sudarjat y Yani Maharani. "Effectiveness of Neem Seed Extract Formulation (Azadirachta Indica) and Bitung (Barringtonia asiatica) against Mealybug Papaya (Paracoccus marginatus) (Hemiptera: Pseudococcidae)". CROPSAVER - Journal of Plant Protection 5, n.º 1 (6 de julio de 2022): 38. http://dx.doi.org/10.24198/cropsaver.v5i1.39803.

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The papaya mealybug (Paracoccus marginatus) Williams & Granara de Wilink (Hemiptera: Pseudococcidae) is a main pest of papaya plants. Attacks by these pests can cause plants failed to produce the fruit and even to death. The usual control technique used by farmers is the use of synthetic pesticides that have a negative impact on human health and the environment. The alternative to control using botanical insecticides is a good solution to control the population of P. marginatus. The purpose of this study is to know the effect of neem seed oil formulation and bitung to know which treatments with concentrations are most effective in reducing the population density of papaya mealybug pests. The experiment took place in Rejasari Village, Langensari Subdistrict, Banjar City, West Java, from March 2021 to July 2021. Experiment using the Randomized Block Design consisted of ten treatments with three replications. The results were obtained that a formulation of bitung 3% could suppress the densities of papaya mealybug ( P. marginatus) populations at 65%. The average weight of the resulting papaya contained a 3% formulation of bitung found at 9.8 kg/tree. botanical pesticides of bitung oil 3% can be used instead of synthetic pesticides to control the population of P.marginatus.
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26

Vallejo Esquerra, Eduardo, David R. Herndon, Francisco Alpirez Mendoza, Juan Mosqueda y Guy H. Palmer. "Anaplasma marginale Superinfection Attributable to Pathogen Strains with Distinct Genomic Backgrounds". Infection and Immunity 82, n.º 12 (6 de octubre de 2014): 5286–92. http://dx.doi.org/10.1128/iai.02537-14.

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ABSTRACTStrain superinfection occurs when a second pathogen strain infects a host already infected with a primary strain. The selective pressures that drive strain divergence, which underlies superinfection, and allow penetration of a new strain into a host population are critical knowledge gaps relevant to shifts in infectious disease epidemiology. In regions of endemicity with a high prevalence of infection, broad population immunity develops againstAnaplasma marginale, a highly antigenically variant rickettsial pathogen, and creates strong selective pressure for emergence of and superinfection with strains that differ in their Msp2 variant repertoires. The strains may emerge either bymsp2locus duplication and allelic divergence on an existing genomic background or by introduction of a strain with a differentmsp2allelic repertoire on a distinct genomic background. To answer this question, we developed a multilocus typing assay based on high-throughput sequencing of non-msp2target loci to distinguish among strains with different genomic backgrounds. The technical error level was statistically defined based on the percentage of perfect sequence matches of clones of each target locus and validated using experimental single strains and strain pairs. Testing ofA. marginale-positive samples from tropical regions whereA. marginaleinfection is endemic identified individual infections that contained unique alleles for all five targeted loci. The data revealed a highly significant difference in the number of strains per animal in the tropical regions compared to infections in temperate regions and strongly supported the hypothesis that transmission of genomically distinctA. marginalestrains predominates in high-prevalence areas of endemicity.
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27

Scoles, Glen A., Massaro W. Ueti y Guy H. Palmer. "Variation Among Geographically Separated Populations ofDermacentor andersoni(Acari: Ixodidae) in Midgut Susceptibility toAnaplasma marginale(Rickettsiales: Anaplasmataceae)". Journal of Medical Entomology 42, n.º 2 (1 de marzo de 2005): 153–62. http://dx.doi.org/10.1093/jmedent/42.2.153.

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28

BAHRAMI, S., H. HAMIDINEJAT, MR HAJI HAJIKOLAEI y S. KAVIANIFAR. "Concurrent occurrence of Anaplasma phagocytophilum and A. marginale in bovine peripheral blood samples from southwest of Iran". Journal of the Hellenic Veterinary Medical Society 71, n.º 3 (15 de octubre de 2020): 2301. http://dx.doi.org/10.12681/jhvms.25076.

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Anaplasma phagocytophilum and A. marginale are the most important tick-borne bacteria of veterinary and public health significance. Anaplasma phagocytophilum causes febrile disease in humans (human granulocytic-HGA) and animals. Anaplasma marginale is the aetiological agent of acute anaplasmosis, a bovine syndrome characterized by progressive hemolytic anemia associated with fever, weight loss, abortion, decreased milk production, and in some cases, death of the infected cattle. The present study was designed to investigate the prevalence of A. phagocytophilum and A. marginale in cattle from Khuzestan province, southwest of Iran. Samples were collected between March to August 2016. Farmed cattle were selected from the four geographic regions of Khuzestan province with the highest population of cattle herds: Behbahan; Dezful; Shushtar; and Ahvaz. Blood samples were collected from the jugular vein of 200 cattle Species specification was accomplished by specific Nested PCR according to amplification of the 16SrRNA gene. To identify A. marginale, semi-nested PCR product was cut with restriction endonucleases Bst 1107 I. The prevalence of the A. marginale infection (21.5 %) was higher than that of A. phagocytophilum (7.5 %), which was found in a mixed infection with A. marginale. Overall, in the present study 7.5% of cattle were infected with both A. phagocytophilum and A. marginale. Despite the healthy appearance of infected cattle, they can transmit Anaplasma to ticks and are potential continuous sources for maintaining and disseminating the organisms to the human and animals’ population. More epidemiological studies are needed to determine the vectors and reservoir animals for the Anaplasma species and to clarify the pathogenicity of A. marginale and A. phagocytophilum for humans and animals in Iran.
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29

Freitag, Gudrun, Claudia Czado y Axel Munk. "A nonparametric test for similarity of marginals—With applications to the assessment of population bioequivalence". Journal of Statistical Planning and Inference 137, n.º 3 (marzo de 2007): 697–711. http://dx.doi.org/10.1016/j.jspi.2006.06.003.

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30

Coates, DJ. "Genetic Diversity and Population Genetic Structure in the Rare Chittering Grass Wattle, Acacia anomala Court". Australian Journal of Botany 36, n.º 3 (1988): 273. http://dx.doi.org/10.1071/bt9880273.

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There are 10 known populations of Acacia anomala occurring in two small disjunct groups some 30 km apart. The Chittering populations reproduce sexually whereas the Kalamunda populations appear to reproduce almost exclusively by vegetative multiplication. The level and distribution of genetic variation were studied at 15 allozyme loci. Two loci were monomorphic in all populations. In the Chittering populations the mean number of alleles per locus was 2.0 and the expected panmictic heterozygosity (genetic diversity) 0.209. In the Kalamunda populations the mean number of alleles per locus was 1.15 and the expected panmictic heterozygosity 0.079, although the observed heterozygosity of 0.150 was only marginally less than the Chittering populations (0.177). These data support the contention that the Chittering populations are primarily outcrossing whereas the Kalamunda populations are clonal, with each population consisting of individuals with identical and, in three of the four populations, heterozygous, multilocus genotypes. The level of genetic diversity within the Chittering populations is high for plants in general even though most populations are relatively smsll and isolated. It is proposed that either the length of time these populations have been reduced in size and isolated is insufficient for genetic diversity to be reduced or the genetic system of this species is adapted to small population conditions. Strategies for the adequate conservation of the genetic resources of Acacia anomala are discussed.
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31

Aspinwall, Joseph A., Shelby M. Jarvis, Susan M. Noh y Kelly A. Brayton. "The Effect of Rickettsia bellii on Anaplasma marginale Infection in Dermacentor andersoni Cell Culture". Microorganisms 11, n.º 5 (22 de abril de 2023): 1096. http://dx.doi.org/10.3390/microorganisms11051096.

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Anaplasma marginale is a tick-borne pathogen that causes bovine anaplasmosis, which affects cattle around the world. Despite its broad prevalence and severe economic impacts, limited treatments exist for this disease. Our lab previously reported that a high proportion of Rickettsia bellii, a tick endosymbiont, in the microbiome of a population of Dermacentor andersoni ticks negatively impacts the ticks’ ability to acquire A. marginale. To better understand this correlation, we used mixed infection of A. marginale and R. bellii in D. andersoni cell culture. We assessed the impacts of different amounts of R. bellii in coinfections, as well as established R. bellii infection, on the ability of A. marginale to establish an infection and grow in D. andersoni cells. From these experiments, we conclude that A. marginale is less able to establish an infection in the presence of R. bellii and that an established R. bellii infection inhibits A. marginale replication. This interaction highlights the importance of the microbiome in preventing tick vector competence and may lead to the development of a biological or mechanistic control for A. marginale transmission by the tick.
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32

Laine, Anna-Liisa, Jeremy J. Burdon, Adnane Nemri y Peter H. Thrall. "Host ecotype generates evolutionary and epidemiological divergence across a pathogen metapopulation". Proceedings of the Royal Society B: Biological Sciences 281, n.º 1787 (22 de julio de 2014): 20140522. http://dx.doi.org/10.1098/rspb.2014.0522.

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The extent and speed at which pathogens adapt to host resistance varies considerably. This presents a challenge for predicting when—and where—pathogen evolution may occur. While gene flow and spatially heterogeneous environments are recognized to be critical for the evolutionary potential of pathogen populations, we lack an understanding of how the two jointly shape coevolutionary trajectories between hosts and pathogens. The rust pathogen Melampsora lini infects two ecotypes of its host plant Linum marginale that occur in close proximity yet in distinct populations and habitats. In this study, we found that within-population epidemics were different between the two habitats. We then tested for pathogen local adaptation at host population and ecotype level in a reciprocal inoculation study. Even after controlling for the effect of spatial structure on infection outcome, we found strong evidence of pathogen adaptation at the host ecotype level. Moreover, sequence analysis of two pathogen infectivity loci revealed strong genetic differentiation by host ecotype but not by distance. Hence, environmental variation can be a key determinant of pathogen population genetic structure and coevolutionary dynamics and can generate strong asymmetry in infection risks through space.
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33

Lawrence, G. J. "Flax rust from Linum marginale: pathogenicity reactions on the Linum usitatissimum set of differential varieties". Canadian Journal of Botany 67, n.º 11 (1 de noviembre de 1989): 3187–91. http://dx.doi.org/10.1139/b89-397.

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Flax rust, Melampsora lini (Ehrenb.) Lév., occurs on Linum marginale Cunn., the only Linum species indigenous to Australia. Evidence suggests that the rust is native to L. marginale and is not a recent introduction. Forty-five isolates from this rust population, collected from 21 locations, were tested for reaction type on the standard set of 28 flax (L. usitatissimum) differential lines. All isolates were avirulent on the majority of differentials and only three clearly different virulence phenotypes were distinguished. This finding contrasts with the results of a companion study in which the same isolates displayed many different virulence phenotypes when tested on a set of L. marginale lines. Two factors apparently contribute to the failure of the L. usitatissimum differentials to detect most of the variation for virulence present in this rust population. First, 10 of the differentials have been reported to possess resistance gene L9 in addition to their designated gene. Since all isolates recognize the L9 gene, these differentials could make no contribution to differentiating between the isolates. Second, many of the L. usitatissimum resistance genes apparently do not occur in L. marginale and with no selection on the rust to conserve or evolve the corresponding virulence genes, the corresponding avirulence genes appear to have become, or remained, fixed in the rust population.
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34

Hilfiker, Karin, Rolf Holderegger, Peter Rotach y Felix Gugerli. "Dynamics of genetic variation in Taxus baccata: local versus regional perspectives". Canadian Journal of Botany 82, n.º 2 (1 de febrero de 2004): 219–27. http://dx.doi.org/10.1139/b03-136.

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Increasing loss of habitat tends to reduce biodiversity at the inter- and intra-specific levels. Within species, the remaining diversity is often partitioned so that a great amount of neutral genetic variation is assigned to among-population variation. This implies reduced gene flow as a consequence of population isolation. We tested whether random amplified polymorphic DNA (RAPD) markers indicate population and (or) regional differentiation in Swiss populations of English yew (Taxus baccata L.), a dioecious forest tree species with scattered distribution. Our sampling included three northern Swiss regions, each containing four populations, and a central-Alpine region with two populations. Four RAPD primers, giving rise to 41 scorable marker bands, identified all but two sampled individuals as unique genotypes. Analyses of molecular variance (AMOVA) detected no significant differentiation among the three northern Swiss regions yet a marginally significant differentiation of these regions versus the central-Alpine region. Concordantly, Mantel tests revealed isolation by distance only when considering all 14 populations. We postulate that the inferred level of gene flow, through wind-borne pollen and occasional long-distance seed dispersal, prevents isolation by distance in northern Switzerland, where stands of T. baccata are relatively abundant. This perpetuates a coherent regional network of occurrences of T. baccata, as might be expected in a metapopulation.Key words: genetic variation, isolation by distance, metapopulation, population differentiation, RAPD-PCR, Taxus baccata.
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35

Nzo-Ayum Ntub Mubanga, Godefroid. "DYNAMIQUE DES RISQUES D’ÉROSION RAVINANTE DES TERRES MARGINALES DE LA COMMUNE RURALE D’IDIOFA (KWILU/R.D. CONGO)". Journal Africain des Sciences 1, n.º 1 (20 de mayo de 2024): 105–14. http://dx.doi.org/10.70237/jafrisci.2024.v1.i1.11.

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The erosion of marginal lands in the Idiofa Rural Commune is a major problem for urban authorities and the local population. This Commune has no integrated stormwater management plan, which has a detrimental impact on its site and its overall socio-economic and cultural development. The main objective of this study is to: (i) Identify the various gullies and their morphometric characteristics, (ii) Map the marginal areas in Idiofa, (iii) Identify the causes of the accelerated gully erosion observed in Idiofa, (iv) Assess the resulting socio-environmental consequences, (v) Understand, discuss and assess the risks, and (vi) Propose strategies to respond to these risks. The method used consisted of two stages: (i) a survey carried out among a sample of 200 people to obtain a population view of the degradation of its environment, (ii) field observations on the inventory of gullies and their dimensions, to complement and validate the data from radar interpretation. EpiData 3.0, Microsoft Excel 2016 and SPSS 22 were used to process the data collected. Thematic maps of the studied phenomenon were designed using ArcMap 10.8, QGIS Desktop 3.36 and Google Earth Pro. According to the results obtained, all the 133 identified ravines left a void volume of approximately 2,530,246 m3. This represents a loss of land of more than 2,000,000 tonnes, with considerable collateral damage.
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36

Bowen, Elizabeth A., Sarah K. Bowen y Anamika Barman-Adhikari. "Prevalence and covariates of food insecurity among residents of single-room occupancy housing in Chicago, IL, USA". Public Health Nutrition 19, n.º 6 (17 de agosto de 2015): 1122–30. http://dx.doi.org/10.1017/s1368980015002384.

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AbstractObjectiveEmerging evidence suggests that food insecurity is a significant public health concern among people who are homeless or marginally housed. The present study assessed prevalence of food insecurity and its covariates among a group of marginally housed individuals living in single-room occupancy (SRO) dwellings, a population for which there is little extant health or nutrition research.DesignCross-sectional survey incorporating the Household Food Insecurity Access Scale.SettingTen private SRO residences in the Uptown neighbourhood of Chicago, IL, USA, 2013.SubjectsSRO residents over 18 years of age who were able to communicate verbally in English (n153).ResultsFood insecurity was widespread among SRO residents, with 75 % of the sample considered food insecure and 52 % meeting criteria for severe food insecurity. Bivariate analyses indicated that female gender, eating most meals at a soup kitchen, having a mental health condition, problem drinking, having at least one chronic health condition, and diabetes were all significantly associated with food insecurity. In the multivariate ordered logistic regression model, eating most meals at a soup kitchen remained as the only significant correlate of food insecurity (OR=10·13).ConclusionsSRO residents and other marginally housed populations face unique food access challenges. Although targeted assistance in the form of food stamps and congregate meal programmes remains critical, efforts to prevent and address food insecurity among homeless and marginally housed individuals should include policy interventions that recognize poverty as the root cause of food insecurity and aim to increase overall income and improve housing conditions.
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37

Helfer, Véronique, Jérôme Pellet y Glenn Yannic. "Estimating population size in the European tree frog (Hyla arborea) using individual recognition and chorus counts". Amphibia-Reptilia 28, n.º 2 (2007): 287–94. http://dx.doi.org/10.1163/156853807780202530.

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AbstractChorus counts are widely used to assess population abundance in breeding anurans. It is however unclear how such counts translate into true population sizes. We monitored chorus activity in two populations of the European tree frog (Hyla arborea) over three years, while simultaneously conducting a capture-mark-recapture (CMR) study on breeding males. Three to four capture sessions were made each year, spread across the acme of the breeding season. Individual recognition was ensured by photographs of the linea marginalis. We used Pollock's robust design to test several biological hypotheses and estimate demographic parameters. Male survival was estimated as mean ±SE = 0.297 ± 0.154. Population trends deduced from chorus counts (maximum or mean) and modelled male population sizes were not concordant. We showed that there is no simple relationship between maximum or mean chorus size and modelled male population sizes estimated from CMR study and that population trends inferred from chorus counts are likely to be biased to an unknown extent. Even though CMR methods need significant time and personnel investments in order to produce reliable results, we advocate their use in the study of pond breeding amphibians' demography, as it provides unbiased and more precise estimates.
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38

Jiang, Shangjun, Mirriam Mikhail, Jackie Slomovic, Austin Pereira, Gerald Lebovic, Christopher Noel y Myrna Lichter. "Prevalence and impact of eye disease in an urban homeless and marginally housed population". Canadian Journal of Ophthalmology 55, n.º 1 (febrero de 2020): 76–81. http://dx.doi.org/10.1016/j.jcjo.2019.07.006.

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39

ROBERTS, JOHN M. K. y ANDREW R. WEEKS. "Genetic structure and long-distance dispersal in populations of the wingless pest springtail, Sminthurus viridis (Collembola: Sminthuridae)". Genetics Research 93, n.º 1 (11 de enero de 2011): 1–12. http://dx.doi.org/10.1017/s0016672310000510.

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SummaryThe lucerne flea, Sminthurus viridis (Collembola: Sminthuridae) (L.) is a major pest of broadacre agriculture across southern Australia. Few molecular studies have been conducted on S. viridis and none have examined its population genetics, despite the importance for developing effective control strategies. Here, we characterize the genetic structure of Australian populations using three allozyme and eight microsatellite loci, as well as sequencing a fragment of the mitochondrial DNA cytochrome oxidase I gene. We found that S. viridis in Australia are diploid, sexually reproducing and exhibit significant population structure as a result of limited gene flow. Despite significant differentiation between populations, there was very low cytochrome oxidase subunit I (COI) gene sequence variation, indicating the presence of a single species in Australia. The observed structure only marginally complied with an ‘isolation by distance’ model with human-mediated long-distance dispersal likely occurring. Allozymes and microsatellites gave very similar FST estimates, although differences found for novel alternative estimates of differentiation suggest that the allozymes did not capture the full extent of the population structure. These results highlight that control strategies may need to vary for locally adapted S. viridis populations and strategies aimed at limiting the spread of any future pesticide resistance will need to manage the effects of human-mediated dispersal.
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40

Reñones, Olga, Amalia Grau, Xavier Mas, Francesc Riera y Fran Saborido-Rey. "Reproductive pattern of an exploited dusky grouper Epinephelus marginatus (Lowe 1834) (Pisces: Serranidae) population in the western Mediterranean". Scientia Marina 74, n.º 3 (25 de mayo de 2010): 523–37. http://dx.doi.org/10.3989/scimar.2010.74n3523.

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41

Lutz, Wolfgang. "Population: The Dynamics of Change". Outlook on Agriculture 22, n.º 4 (diciembre de 1993): 211–19. http://dx.doi.org/10.1177/003072709302200402.

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Global population growth is generally considered to be one of the major driving forces of global change. Population changes, however, follow their own dynamics and can be influenced only marginally in the short run. This paper outlines the basic structure of these dynamics, including the important momentum of population growth. It also presents alternative population projections that show that in the long run much depends on fertility trends in the near future, and that a successful curbing of population growth will result in very rapid and significant population aging.
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42

Kortz, Alessandra, Martin Hejda, Jan Pergl, Josef Kutlvašr, Petr Petřík, Jiří Sádlo, Michaela Vítková, Martin Vojík y Petr Pyšek. "Impacts of native and alien plant dominants at different spatial scales". NeoBiota 92 (12 de marzo de 2024): 29–43. http://dx.doi.org/10.3897/neobiota.92.116392.

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Plant invasion science has made a substantial progress in documenting the impacts of aliens, but comparisons with the impacts of native dominants are still rare. Further, the impacts on larger spatial scales remain poorly understood. We recorded the impacts of 10 native and nine invasive dominant plants in the Czech Republic on species richness and Shannon diversity by comparing communities with high vs. low cover of the dominant species. To estimate the impacts at the (i) population level and (ii) between-population level, we compared the Jaccard dissimilarity, nestedness and turnover of high- and low-dominance plots. Further, we calculated the Jaccard dissimilarity, nestedness and turnover between the high- and low-dominance plots within each population to express the impacts on species composition. We tested whether (i) native and invasive dominants affect the population- and between population levels of diversity by making the vegetation more homogenous; (ii) whether these effects differ between the native and alien dominants; and (iii) whether the impacts at different spatial levels are related. At the population level, high-dominance plots (with both native and alien dominants) showed higher nestedness and lower turnover compared to the low-dominance plots. Further, all plots with native dominants, both with high- and low dominance, showed higher similarity but lower nestedness than plots with alien dominants. Most importantly, high-dominance plots with native dominants were more similar to each other but showed marginally significantly lower nestedness compared to high-dominance plots with alien dominants. At the between-population level, high-dominance plots with native dominants showed a marginally significantly lower turnover compared to high-dominance plots with alien dominants. The differences in Jaccard dissimilarity, nestedness and turnover between the low- and high-dominance plots at the population level showed strong positive relations to low- and high-dominance differences at the between-populations level. Further, compositional impacts, expressed as the dissimilarity between high- vs. low-dominance plots, positively related to the plot-level impacts on Shannon diversity. Our results show that (i) both native and invasive dominants tend to reduce the diversity over larger areas and that the effect of native dominants may be even stronger, and (ii) the effects on plot-level richness and diversity cannot be easily extrapolated to larger scales but the impacts at the population- and between-populations levels are positively related.
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43

Chen, S., A. Hill, W. Jackson, B. Munk, M. Saunders, S. Gassama y G. Maier. "Prevalence and risk factors for Anaplasma marginale seropositivity in cattle in California". American Association of Bovine Practitioners Conference Proceedings, n.º 56 (10 de mayo de 2024): 189. http://dx.doi.org/10.21423/aabppro20238899.

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Bovine anaplasmosis, a tick-borne disease caused by Anaplasma marginale, imposes considerable economic bur­den on cattle industries throughout the world. Clinical signs of bovine anaplasmosis include fever, weight loss, lethargy, jaundice, abortion and death. The severity of the disease in­creases with age, and calves under 1 year of age generally do not progress to clinical disease or develop mild disease. Once infected, cattle remain persistently infected carriers for life. Climate change and drought conditions may affect the distri­bution and prevalence of tick populations and tick-borne dis­eases and re-evaluating the seroprevalence of Anaplasma would provide a better understanding of the disease dynamics in California. To our knowledge, there has been no updated study regarding the distribution of Anaplasma infection status in California since 2008, and the information on weather factors related to the disease is also limited. There is an urgent need to evaluate the prevalence of Anaplasma infection in different regions of California. The goal of this study is to estimate the seroprevalence of Anaplasma infection in California cattle over time, and the specific goal is to identify potential risk factors for infection including animal demographics, region, Anaplasma seroprevalence of wild ruminants, Dermacentor tick species presence, and weather effects.
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44

Burdon, J. J. y John N. Thompson. "Changed Patterns of Resistance in a Population of Linum Marginale Attacked by the Rust Pathogen Melampsora Lini". Journal of Ecology 83, n.º 2 (abril de 1995): 199. http://dx.doi.org/10.2307/2261558.

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Nemri, Adnane, Luke G. Barrett, Anna-Liisa Laine, Jeremy J. Burdon y Peter H. Thrall. "Population Processes at Multiple Spatial Scales Maintain Diversity and Adaptation in the Linum marginale - Melampsora lini Association". PLoS ONE 7, n.º 7 (31 de julio de 2012): e41366. http://dx.doi.org/10.1371/journal.pone.0041366.

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46

Wright, John M., Laura M. Parker, Wayne A. O’Connor, Mark Williams, Peter Kube y Pauline M. Ross. "Populations of Pacific Oysters Crassostrea gigas Respond Variably to Elevated CO2 and Predation by Morula marginalba". Biological Bulletin 226, n.º 3 (junio de 2014): 269–81. http://dx.doi.org/10.1086/bblv226n3p269.

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47

French, Dorothy M., Terry F. McElwain, Travis C. McGuire y Guy H. Palmer. "Expression of Anaplasma marginale Major Surface Protein 2 Variants during Persistent Cyclic Rickettsemia". Infection and Immunity 66, n.º 3 (1 de marzo de 1998): 1200–1207. http://dx.doi.org/10.1128/iai.66.3.1200-1207.1998.

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ABSTRACT Anaplasma marginale is an intraerythrocytic rickettsial pathogen of cattle in which infection persists for the life of the animal. Persistent A. marginale infection is characterized by repetitive rickettsemic cycles which we hypothesize reflect emergence of A. marginale antigenic variants. In this study, we determined whether variants of major surface protein 2 (MSP-2), a target of protective immunity encoded by a polymorphic multigene family, arise during persistent rickettsemia. By using a quantitative competitive PCR to identify rickettsemic cycles,msp-2 transcripts expressed in vivo were isolated from peak rickettsemia of sequential cycles. Cloning and sequencing ofmsp-2 cDNA revealed that genetic variants of MSP-2 emerge representing a minimum of four genetic variant types in each cycle during persistent infection. Two-color immunofluorescence using variant-specific antibody showed that emergence of MSP-2 variants resulted in expression of a minimum of three antigenic types of MSP-2 within one rickettsemic cycle. Therefore immune control of each cycle would require responses to an antigenically diverse A. marginale population. These findings demonstrate that polymorphic MSP-2 variants emerge during cyclic rickettsemia in persistent A. marginale infection and suggest that emergent variants play an important role in persistence.
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48

Silva, Daniela de M. e., Aparecido D. da Cruz, Rogério P. Bastos, Mariana P. de C. Telles y José Alexandre F. Diniz-Filho. "Morphometric and genetic differentiation among populations of Eupemphix nattereri (Amphibia, Anura, Leiuperidae) from central Brazil". Iheringia. Série Zoologia 98, n.º 4 (diciembre de 2008): 493–500. http://dx.doi.org/10.1590/s0073-47212008000400013.

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To assess genetic structure and phenotypic diversity of Eupemphix nattereri Steindachner, 1863, morphometric and molecular analyses were carried out for nine populations from the State of Goiás. A total of 11 morphometric traits were evaluated and genetic information was estimated using RAPD markers. Genetic and phenotypic distances were determined as a function of geographical origin. Correlation among genetic, morphometric, micro, and macroenviromental were analyzed by the Mantel test. Genetic data indicated high levels of genetic diversity (Φst= 0.3) among the nine populations. Mantel tests did not reveal a significant positive correlation between genetic and geographical distances, indicating that locally geographical populations were not genetically similar, even in distances smaller than 50 km. Discriminant analysis on 11 morphometric measurements showed a high divergence among the nine populations. However, a marginally significant correlation (P=0.08) between genetic and morphometric distances was found. The observed correlation was not causal in terms of the relationship between phenotype and genotype, but indicated common spatial structures. Thus, our results suggest that isolation-by-distance processes may explain population divergence in Eupemphix nattereri.
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49

Mc Crae, Katherine y Marie Lacroix. "L’intervention en contexte de crise économique : le travail social avec les mineurs non accompagnés en Espagne". Service social 60, n.º 1 (22 de mayo de 2014): 34–48. http://dx.doi.org/10.7202/1025132ar.

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Dans le cadre d’un stage international de maîtrise réalisé à Grenade, Espagne, nous avons eu l’occasion de nous pencher sur la problématique des jeunes mineurs non accompagnés et de repenser le rôle du travailleur social dans un contexte de crise économique avec une population vulnérable. La question des mineurs se pose avec beaucoup d’acuité pour les travailleurs sociaux de divers pays d’Europe à l’heure actuelle, surtout si l’on considère l’impact des mesures d’austérité dans tous les domaines des politiques sociales du social. Le présent article documente cette expérience de stage et soulève des questions pour la pratique du service social qui sont valables tant pour le Québec que pour d’autres sociétés où de plus en plus les populations immigrantes se voient reléguées à une position marginale dans les sociétés d’accueil.
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de la Fuente, José y Katherine M. Kocan. "Expression of Anaplasma marginale Major Surface Protein 2 Variants in Persistently Infected Ticks". Infection and Immunity 69, n.º 8 (1 de agosto de 2001): 5151–56. http://dx.doi.org/10.1128/iai.69.8.5151-5156.2001.

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ABSTRACT Anaplasma marginale, an intraerythrocytic ehrlichial pathogen of cattle, establishes persistent infections in both vertebrate (cattle) and invertebrate (tick) hosts. The ability ofA. marginale to persist in cattle has been shown to be due, in part, to major surface protein 2 (MSP2) variants which are hypothesized to emerge in response to the bovine immune response. MSP2 antigenic variation has not been studied in persistently infected ticks. In this study we analyzed MSP2 in A. marginalepopulations from the salivary glands of male Dermacentor variabilis persistently infected with A. marginaleafter feeding successively on one susceptible bovine and three sheep. New MSP2 variants appeared in each A. marginale population, and sequence alignment of the MSP2 variants revealed multiple amino acid substitutions, insertions, and deletions. These results suggest that selection pressure on MSP2 occurred in tick salivary glands independent of the bovine immune response.
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