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1.
Phys Rev Lett ; 132(9): 096001, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38489619

ABSTRACT

We suggest a theoretical description of the photogalvanic phenomena arising in superconducting condensates in the field of electromagnetic wave. The ac Hall effect and photon drag are shown to originate from the second-order nonlinear response of superconducting carriers caused by the suppression of their concentration due to the combined influence of the electron-hole asymmetry and charge imbalance generated by the incident electromagnetic wave. Starting from the time-dependent Ginzburg-Landau theory with the complex relaxation constant, we develop a phenomenological description of these phenomena and investigate the resulting behavior of the dc supercurrent and second harmonic induced by microwave radiation incident on a superconductor surface.

2.
Phys Rev Lett ; 126(13): 137002, 2021 Apr 02.
Article in English | MEDLINE | ID: mdl-33861134

ABSTRACT

The Cooper pairs in superconducting condensates are shown to acquire a temperature-dependent dc magnetic moment under the effect of the circularly polarized electromagnetic radiation. The mechanisms of this inverse Faraday effect are investigated within the simplest version of the phenomenological dynamic theory for superfluids, namely, the time-dependent Ginzburg-Landau (GL) model. The light-induced magnetic moment is shown to be strongly affected by the nondissipative oscillatory contribution to the superconducting order parameter dynamics, which appears due to the nonzero imaginary part of the GL relaxation time. The relevance of the latter quantity to the Hall effect in the superconducting state allows us to establish the connection between the direct and inverse Faraday phenomena.

3.
Ticks Tick Borne Dis ; 10(2): 377-385, 2019 02.
Article in English | MEDLINE | ID: mdl-30509727

ABSTRACT

The study objective was to get more information on C. burnetii prevalence in wild birds and ticks feeding on them, and the potentialities of the pathogen dissemination over Europe by both. MATERIALS: Blood, blood sera, feces of wild birds and ticks removed from those birds or from vegetation were studied at two sites in Russia: the Curonian Spit (site KK), and the vicinity of St. Petersburg (site SPb), and at two sites in Bulgaria: the Atanasovsko Lake (site AL), and the vicinity of Sofia (site SR). METHODS: C. burnetii DNA was detected in blood, feces, and ticks by PCR (polymerase chain reaction). All positive results were confirmed by Sanger's sequencing of 16SrRNA gene target fragments. The antibodies to C. burnetii in sera were detected by CFR (complement fixation reaction). RESULTS: Eleven of 55 bird species captured at KK site hosted Ixodes ricinus. C. burnetii DNA was detected in three I. ricinus nymphs removed from one bird (Erithacus rubecula), and in adult ticks flagged from vegetation: 0.7% I. persulcatus (site SPb), 0.9% I. ricinus (site KK), 1.0% D. reticulatus (AL site). C. burnetii DNA was also detected in 1.4% of bird blood samples at SPb site, and in 0.5% of those at AL site. Antibodies to C. burnetii were found in 8.1% of bird sera (site SPb). C. burnetii DNA was revealed in feces of birds: 0.6% at AL site, and 13.7% at SR site. CONCLUSIONS: Both molecular-genetic and immunological methods were applied to confirm the role of birds as a natural reservoir of C. burnetii. The places of wild bird stopover in Russia (Baltic region) and in Bulgaria (Atanasovsko Lake and Sofia region) proved to be natural foci of C. burnetii infection. Migratory birds are likely to act as efficient "vehicles" in dispersal of C. burnetii -infested ixodid ticks.


Subject(s)
Animals, Wild/microbiology , Bird Diseases/epidemiology , Birds/microbiology , Coxiella burnetii/isolation & purification , Ixodes/microbiology , Q Fever/veterinary , Animal Migration , Animals , Antibodies, Bacterial/blood , Baltic States/epidemiology , Bird Diseases/microbiology , Bulgaria/epidemiology , Coxiella burnetii/genetics , DNA, Bacterial/isolation & purification , Disease Reservoirs/microbiology , Disease Reservoirs/veterinary , Europe/epidemiology , Feces/microbiology , High-Throughput Nucleotide Sequencing , Nymph/microbiology , Polymerase Chain Reaction , Prevalence , Q Fever/epidemiology , RNA, Ribosomal, 16S/isolation & purification , Russia/epidemiology , Tick Infestations/epidemiology , Tick Infestations/microbiology
4.
Phys Rev Lett ; 121(7): 077002, 2018 Aug 17.
Article in English | MEDLINE | ID: mdl-30169060

ABSTRACT

We show that a wide class of layered superconductor-ferromagnet (S/F) hybrids demonstrates the emergence of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase well below the superconducting transition temperature. By decreasing the temperature, one can switch the system from uniform to the FFLO state which is accompanied by the damping of the diamagnetic Meissner response down to zero and also by the sign change in the curvature of the current-velocity dependence. Our estimates show that an additional layer of the normal metal (N) covering the ferromagnet substantially softens the conditions required for the predicted FFLO instability, and for existing S/F/N systems, the temperature of the transition into the FFLO phase can reach several kelvins.

5.
Nat Commun ; 7: 12801, 2016 Sep 28.
Article in English | MEDLINE | ID: mdl-27677835

ABSTRACT

Magnetic field can penetrate into type II superconductors in the form of Abrikosov vortices, which are magnetic flux tubes surrounded by circulating supercurrents often trapped at defects referred to as pinning sites. Although the average properties of the vortex matter in superconductors can be tuned with magnetic fields, temperature or electric currents, handling of individual Abrikosov vortices remains challenging and has been demonstrated only with sophisticated scanning local probe microscopies. Here we introduce a far-field optical method based on local heating of the superconductor with a focused laser beam to realize a fast and precise manipulation of individual vortices, in the same way as with optical tweezers. This simple approach provides the perfect basis for sculpting the magnetic flux profile in superconducting devices like a vortex lens or a vortex cleaner, without resorting to static pinning or ratchet effects.

6.
Phys Rev Lett ; 115(2): 027601, 2015 Jul 10.
Article in English | MEDLINE | ID: mdl-26207504

ABSTRACT

We report direct evidence of the electric field induced by a magnetization inhomogeneity in an iron garnet film. This inhomogeneity was created by the nonuniform magnetic fields generated at domain boundaries of a type-I superconductor in the intermediate state. At liquid helium temperatures, Stark shifts of sharp single-molecule zero-phonon lines were used to probe the local electric fields generated by this flexomagnetoelectric effect. The measured electric fields are in accordance with theoretical estimations.

7.
Phys Rev Lett ; 114(22): 227001, 2015 Jun 05.
Article in English | MEDLINE | ID: mdl-26196639

ABSTRACT

We show that the critical current of the Josephson junction consisting of superconducting electrodes coupled through a nanowire with two conductive channels can reveal the multiperiodic magnetic oscillations. The multiperiodicity originates from the quantum mechanical interference between the channels affected by both the strong spin-orbit coupling and the Zeeman interaction. This minimal two-channel model is shown to explain the complicated interference phenomena observed recently in Josephson transport through Bi nanowires.

8.
Parazitologiia ; 47(3): 212-27, 2013.
Article in Russian | MEDLINE | ID: mdl-24455905

ABSTRACT

Various data considered as possible cases where metazoans return form the obligate parasitism to free mode of life (a violation of ecological interpretation of Dollo's law). It is shown that among temporary and phase parasites their return to the free mode of life is a rare but not exceptional phenomenon. It is possibly to conclude that these cases are displayed only by those ectoparasitic arthropods, ancestors of which were predators. The only, although incompletely proven cases of the violation of Dollo's law among permanent parasites is suggested to be acariform mites of the family Pyroglyphidae (Acariformes: Psoroptoidea).


Subject(s)
Parasites/physiology , Phylogeny , Psoroptidae/physiology , Animals
10.
Article in Russian | MEDLINE | ID: mdl-20499691

ABSTRACT

In the Nizhegorod Medical Academy a sociological survey was conducted to ascertain the attitude of students to their health and lifestyle. The results of the questionnaire survey showed that the majority of future health workers do not seek to follow a healthy lifestyle. The findings were used in the working out of a target complex program "Health of students of the Nizhegorod Medical Academy for 2006-2009" for the future retrospective analysis of activities conducted.


Subject(s)
Educational Measurement/methods , Health Status , Life Style , Students, Medical , Adolescent , Female , Humans , Male , Retrospective Studies , Russia , Young Adult
11.
J Parasitol ; 95(5): 1093-107, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19281277

ABSTRACT

Three new species of the feather mite genus Proterothrix (Proctophyllodidae: Pterodectinae) are reported from parrotbills (Passeriformes: Paradoxornithidae) in China. We describe Proterothrix paradoxornis n. sp. from Paradoxornis webbianus (type host) and Par. alphonsianus, P. longicaula n. sp. from Par. gularis, and P. sarahbushae n. sp. from Par. verreauxi (type host) and Par. alphonsianus. These are the first records of mites of the Pterodectinae from the Paradoxornithidae. Within Proterothrix, the new species constitutes a distinct complex, characterized by the presence of a long, whip-like aedeagus and spindle-shaped setae e on tarsi I in males.


Subject(s)
Bird Diseases/parasitology , Feathers/parasitology , Mite Infestations/veterinary , Mites/classification , Passeriformes/parasitology , Animals , China , Diagnosis, Differential , Female , Male , Mite Infestations/parasitology , Mites/anatomy & histology
12.
Parazitologiia ; 42(2): 81-100, 2008.
Article in Russian | MEDLINE | ID: mdl-18664065

ABSTRACT

The term synhospitality means the association of two or more closely related parasite species with one host species (Eichler, 1966). The cases of two or three synhospitalic species are known from the same host species, and especially ones where parasites were recorded from different parts of the host range, are quite common. The most ordinary reason causing synhospitality in permanent parasites is the host switching. Nevertheless, there are a number of synhospitality cases, where the parasite complex is monophyletic because evolved on a single host species. The special term--"phylogenetic synhospitality" (FS) is proposed for these cases of synhospitality. Most known cases of FS in acariform mites, permanent parasites of vertebrates, are analysed. It is found out that both astigmatan and prostigmatan parasite mites demonstrate a numbers of FS. The majority of these examples represent parasitism of two or three synhospitalic parasite species. Impressive examples of FS involving a number of synhospitalic species is shown by only astigmatan mites inhabiting the fur of mammals or plumage of birds. Most known examples involving four or more mite species are discussed: 51 mite species of the genus Schizocarpus (Chirodiscidae) parasitizing Castor fiber and C. canadensis (Castoridae); 6 species of Listrophorus spp. (Listrophoridae) from Ondatra zibethicus (Cricetidae); 23 species of Listrophoroides s. 1. (Atopomelidae) from Maxomys surifer (Muridae); 21 species of Cytostethum (Atomelidae) from Potorous tridactylus (Potoridae); 4 species of Listrophoroides (Afrolistrophoroides) from Malacomys longipes (Muridae); 7 species of Fainalges (Xolalgidae) from Aratinga holochlora (Psittacidae); 4 species of Zygepigynia (Pteronyssidae) from Chrysocolaptes lucidus (Picidae). The main reason of FS is that, in spite of the Fahrenholz's rule, the speciation of many parasites proceeds much more intensively than in their hosts because of the more rapid replacement of the parasitic generations. The first factor causing FS is the mite speciation it temporary segregated populations of the host (allopatric speciation). In this case, the "multispecies complexes" appeared after the subsequent reintegration of the host populations formerly isolated. The second factor is the speciation due to the specialization of mites to local microhabitats in the fur or plumage of host (sympatric or synxenic speciation). The second way of speciation is most characteristic for mites with highly specialized attaching structures. The phenomenon of FS more resides in ectoparasites of mammals rather than in feather mites in spite of much more structural complicacy of plumage rather than the fur. The high mobility of birds and wide dispersion of their new generations probably embarrass the process of sympatric speciation in their parasites. As a rule, only really significant geographical barriers play role for population isolation in birds. Thus, it could be concluded that two independent factors or their combination lead to FS. (i) The complex and/or disjunctive host range giving a possibility for allopatric speciation in parasites. (ii) The deep mite specialization to local microhabitats on the host body causing sympatric (synxenic) speciation. Fur of mammals and plumage of birds are very complicated in structure and microconditions and provide a considerable number of different microhabitats for mites inhabiting them. The prevalence of one of these two factors depends on the biological peculiarities of both parasites and their hosts. In mites with lesser specialized attaching organs, for example in atopomelids, allopatric speciation dominates. In mites with strongly specialized attaching organs, for example in listrophorids or chirodiscids, both pathways of speciation may take place. In feather mites, sympatric speciation should be more probable due to quite complicate and various structure of feathers in avian hosts. In fur mites, sympatric speciation is more likely in mites parasitizing hosts with peculiar ecology, for example in semiaquatic rodents possessing quite different fur structure in different parts of the body.


Subject(s)
Acari/physiology , Symbiosis , Vertebrates/parasitology , Animals , Host-Parasite Interactions , Rodentia/parasitology
13.
J Parasitol ; 94(6): 1243-8, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18576859

ABSTRACT

A new feather mite species, Ingrassia eudyptula n. sp. (Xolalgidae: Ingrassiinae), is described from the blue penguin Eudyptula minor (J.B. Forster, 1781) in Australia. This is the first description of a feather mite species from representatives of the avian order Sphenisciformes, which had previously been considered free from feather mites due to their strongly modified plumage and highly aquatic lifestyle. We suggest that most probably this mite species or its ancestor moved onto penguins from a shearwater species (Procellariiformes: Procellariidae) via shared nesting burrows in seabird colonies. In support of this argument, we illustrate similarities between I. eudyptula n. sp. and the closely related I. dubinini Cerny, 1967 from shearwaters (Puffinus spp.).


Subject(s)
Bird Diseases/parasitology , Feathers/parasitology , Mite Infestations/veterinary , Mites/classification , Spheniscidae/parasitology , Animals , Australia , Female , Male , Mite Infestations/parasitology , Mites/anatomy & histology
14.
Morfologiia ; 131(2): 43-5, 2007.
Article in Russian | MEDLINE | ID: mdl-17583007

ABSTRACT

Two lines of rats, selected according to the excitability of nervous system to the action of an electric current, served as the model objects to study the changes of heterochromatin characteristics in neurons of hippocampus (area CA3) 24 hours, 2 weeks, 2 and 6 months after exposure to prolonged emotional painful stress. It was shown that exposure to stress caused changes in the area, occupied by heterochromatin, only in rats with low-excitability: it was decreased 24 hours, 2 weeks and 2 months following the stress, while it was increased after 6 months as compared to control values. Thus, it was demonstrated for the first time that long-term modifications of heterochromatin structural characteristics of neurons in hippocampus (area CA3) could depend on genetically determined functional state of the nervous system.


Subject(s)
Heterochromatin/ultrastructure , Hippocampus/ultrastructure , Neurons/ultrastructure , Stress Disorders, Post-Traumatic/pathology , Stress, Psychological/pathology , Animals , Disease Models, Animal , Electric Stimulation , Male , Nervous System Physiological Phenomena , Rats , Rats, Inbred Strains , Stress, Psychological/genetics
15.
Bull Exp Biol Med ; 138(2): 113-5, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15662448

ABSTRACT

New data were obtained on modification of heterochromatin parameters in the nuclei of medulla oblongata neurons in Wistar rats after stimulation of the vagus nerve: decrease in the area of heterochromatin regions and redistribution of chromocenters within the neuronal nuclear system. It was concluded that realization of the viscero-visceral reflex is associated with rearrangement of chromatin in neurons involved in transmission of the corresponding information.


Subject(s)
Heterochromatin/ultrastructure , Medulla Oblongata/physiology , Vagus Nerve/physiology , Animals , Electric Stimulation , Male , Medulla Oblongata/ultrastructure , Neurons/ultrastructure , Rats , Rats, Wistar , Reflex/physiology , Solitary Nucleus/physiology , Solitary Nucleus/ultrastructure
16.
Bull Exp Biol Med ; 135(2): 161-3, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12802424

ABSTRACT

The structural (number and area of chromocenters) and optical (relative optical density of chromocenters) characteristics of condensed chromatin in hippocampal CA3 neurons in rats differing by excitability of the nervous system (intact and exposed to short-term emotional painful stress) depended on the time of the day and genotypical characteristics of the experimental animals. The detected changes were independent, which attests to specificity of mechanisms determining these features and/or can be attributed to structural and functional heterogeneity of condensed chromatin (heterochromatin, euchromatin, etc.).


Subject(s)
Chromatin/metabolism , Hippocampus/cytology , Interphase , Neurons/physiology , Stress, Psychological , Animals , Circadian Rhythm/genetics , Male , Rats , Rats, Inbred Strains
17.
Parazitologiia ; 36(5): 356-74, 2002.
Article in Russian | MEDLINE | ID: mdl-12481604

ABSTRACT

A process of infecting the chaffinch nestlings Fringilla coelebs with three analgoid feather mites, Analges passerinus L., 1758, Monojoubertia microphylla (Robin, 1877), and Pteronyssoides striatus (Robin, 1977), commonly occurred on this bird species was investigated. 15 nests contained totally 65 nestlings, from 2 to 6 individuals in a brood, have been examined from the day of hatching till 11th day. Observations were held in the neighbourhood of the bird banding station "Rybachy" (Russia, Kaliningrad Province) in June of 1982. Number of mites on alive nestlings taken temporarily from their nest was counted by means of binocular lens under the magnification x12.5 and x25. The nestlings receive the mites from the chaffinch female during the night time, when the female sits together with the young birds and heats them. In the condition of this prolonged direct contact the mites migrate from the female onto the nestlings. As it was shown in our study of seasonal dynamics of mites on the chaffinch (Mironov, 2000), the chaffinch female only gives its mites to young generation and looses about three quarter of its mite micropopulation during the nesting period (June), hile in the chaffinch males the number of mites continues to increase during all summer. The infections with three feather mite species happen in the second part of the nestling's stay in the nest. The starting time of this process, its intensity, and sex and age structure of mite micropopulations on the nestlings just before their leaving the nest are different in the mite species examined. These peculiarities of feather mite species are determined by the biology of examined species, and first of all by their morphological characteristic and specialisation to different microhabitats, i.e. certain structural zones of plumage. Pteronyssoides striatus (Pteronyssidae) is rather typical mite specialised to feathers with vanes. In adult birds with completely developed plumage this species occupies the ventral surface of the big upper coverts of primary flight feathers. This species appears on the chaffinch nestlings in a significant number on 7th day. The mites occupy the basal parts of primary flight feathers represented in that moment by the rods only. They sit on practically open and smooth surface of this microhabitat, which is uncommon for them, because the vanes of the big upper coverts are not yet open and also represented by thin rods. During the period of the last 5 days (from 7 to 11th day) the mean number of mites per one nestling increases from 2.3 +/- 0.5 to 17.1 +/- 1.8 mites. Just before the day, when the nestling leave the nest, the tritonymphs absolutely predominate (82.4%) in the micropopulation of P. striatus. Analges passerinus (Analgidae) is specialised to live in the friable layer formed by numerous not-engaged thread barbles of the down feathers and basal parts of the body covert feathers. Mites have special hooks on legs used for hard attaching to the barbles and for fast moving in the friable layer of feathers. On the chaffinch nestlings, these mites appear usually on 8th day, when the rod-like body covert feathers begin to open on apices and form short brushes; however some individuals occur on the skin of nestlings even on 6th day. The mean number of mites per nestling on the 11th day reaches 16.5 +/- 1.4 individuals. The micropopulation of A. passerinus is represented on the nestlings mainly by the females (45.5%), tritonymphs (23.6%) and males (11.5%). Monojobertia microphylla (Proctophyllodidae) is a typical dweller of feathers with large vanes. Mites of this species commonly occupy the ventral surface of primary and secondary flight feathers and also respective big upper covert feathers of wings. M. microphylla appears on the nestlings in a significant number (7.1 +/- 1.2 mites) on 9th day, only when the primary flight feathers already have short vanes about 10 mm in length. In next three days the number of mites increases very fast and reaches on 11th day 60.3 +/- 5.7 mites per nestling. In the micropopulation of this species, the tritonymphs count 38.3%, and the quota of males and females is 25.3% each. The migration of this species goes most intensively, than in two other species. An analitic selection of logistic curves shows, that the increasing of mite number during the process of infection with three mite species may be most adequately described by the sigmoid curves with clearly recognizable levels of saturation, which can be theoretically reached. Indeed, the number of mite individuals being able to migrate onto the nestlings is limited by their number on a respective chaffinch female. In a contrast, the increasing of plumage indices, for instance the length of flight feathers, has almost linear character during the period of observation. The beginning of mite migration is determined by the development of respective microhabitats in the plumage of nestlings, or at least by the development of certain structure elements of plumage, where mites are able to attach for a while, before that moment, when the nestlings will develop the plumage completely and begin to fly. In three mite species examined, the process of infection was performed by older stages, namely by the imago and/or tritonymphs. This can be explained by two reasons. On the one hand, the older stages are most active in their movement, resistible and able to survive successfully on new host individuals. On the other hand, the older stage are ready for the reproduction or will be ready after one moulting. The older stages of mites can quickly create a large and self-supporting micropopulations on the birds, therefore this strategy ensures a successful subsequent existence of the parasite species. In cases, when mites (A. passerinus, M. microphylla) migrate into the respective microhabitats structurally corresponding to their normal microhabitats on adult birds, the micropopulations of these mite species include a significant or dominant quota of females and males. When the normal microhabitat is not yet formed, feather mites migrate into neighboring structure elements of plumage, where they can survive and wait for the development of normal microhabitat, to which they are well adapted. Therefore, in the case of P. striatus, its micropopulations on the chaffinch nestlings are represented mainly by the tritonymphs.


Subject(s)
Bird Diseases/parasitology , Feathers/parasitology , Mite Infestations/parasitology , Mites/physiology , Songbirds/parasitology , Animals , Arachnid Vectors , Host-Parasite Interactions , Mites/classification , Population Density , Russia
18.
Parazitologiia ; 35(4): 284-90, 2001.
Article in Russian | MEDLINE | ID: mdl-11605453

ABSTRACT

A representative of the family Apionacaridae is recorded from the passerine birds Passeriformes for the first time. Fringillosphaera bochkovi gen. n., sp. n. is described from the chaffinch Fringilla coelebs (Fringillidae). The new genus obtains main diagnostic characters as follows. Vertical setae vi absent. Prodorsal shield free from scapular sheilds and epimerites Ia. Humeral sheilds present. Epimerites I convergent, connected by sclerotized plate. Lateral setae f2 and pseudanal setae ps3 absent. Coxal fields I-IV sclerotized. In male: legs IV present, genital apparatus at level of trochanters IV, genital arch with divergent branches. Epiandrium absent. Coxal setae 3a absent. Morphological peculiarities, host associations and phylogenetic relationships of the family Apionacaridae are briefly discussed. It is suggested that this family represents and ancient and relic phylogenetic branch, which had split rather early from the common ancestor of the superfamily Analgoidea in the period of formation of the Neognathae birds.


Subject(s)
Feathers/parasitology , Mites/anatomy & histology , Songbirds/parasitology , Animals , Mites/classification , Phylogeny , Russia
19.
Parazitologiia ; 35(2): 135-41, 2001.
Article in Russian | MEDLINE | ID: mdl-11548579

ABSTRACT

Thirty nine specimens of passerine birds belonging to 19 species and eight families were investigated by blood smear technique in four localities of Southern Turkmenistan in 3-18 August 1991. The overall prevalence of infection was 59%. Protists from the orders Haemosporida (genera Haemoproteus, Plasmodium, Leucocytozoon), Kinetoplastida (Trypanosoma), and Adeleida (Hepatozoon), as well as Microfilaria were found. Haemoproteids (the prevalence of infection is 44%), leucocytozoids (23%), malarial parasites (13%) and trypanosomes (13%) were most frequently recorded. Only low chronic infections (< 1% of infected cells for the great majority of intracellular parasites, and a few trypanosomes and Microfilaria in each blood smear) were seen. Haemoproteus belopolskyi, H. balmorali, H. dolniki, H. magnus, H. minutus, H. fringillae, H. majoris, Leucocytozoon dubreuili, and Trypanosoma avium were recorded for the first time in Turkmenistan. The former five above-mentioned species of haemoproteids are new records for the fauna of Middle Asia. Gametocytes of leucocytozoids in fusiform host cells were found for the first time in passerine birds in the Holarctic. The host is Parus bokharensis. Due to the wide distribution and the opportunity to collect a large parasitological material using harmless for hosts methods, bird haemosporidian parasites can be used as convenient models for ecological and evolutionary biology studies in South Turkmenistan. The heavily infected Orphean Warbler Sylvia hortensis is an especially convenient host for such purposes.


Subject(s)
Parasites/parasitology , Songbirds/parasitology , Animals , Parasites/classification , Parasites/physiology , Songbirds/blood , Turkmenistan
20.
Mol Phylogenet Evol ; 20(1): 124-35, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11421653

ABSTRACT

Phylogenetic relationships among feather mites of the subfamily Avenzoariinae (Acari: Analgoidea: Avenzoariidae) were reconstructed by parsimony analysis of a combined data matrix. We analyzed 41 morphological characters and 246 molecular characters from a fragment of the 16S rDNA. Morphological trees were well supported at deep branches (genera and above), but showed much less support and resolution within genera. Molecular analyses produced trees with better resolution and support on terminal branches and worse support on basal branches. I(MF) index for the combined matrix pointed to the significant congruence of both data subsets with the whole of the data. The topology of the combined tree was close to the morphological tree in the deep branches and had well-resolved terminal branches as in the molecular tree. This suggests a considerable level of complimentarity between the two data sets. An analysis of association patterns of the mites and their hosts was conducted based on the results of the combined analyses for the Avenzoariinae and a phylogeny of their charadriiform hosts (compiled from various bird phylogeny hypotheses). The trees could be reconciled by the invoking of 12-13 cospeciation events, 6-7 duplications, 2 host shifts, and 26-29 sorting events. This suggests a high degree of cospeciation.


Subject(s)
Mites/genetics , Phylogeny , Animals , Birds/genetics , Birds/parasitology , DNA, Mitochondrial/chemistry , DNA, Mitochondrial/genetics , Evolution, Molecular , Host-Parasite Interactions , Mites/anatomy & histology , Mites/classification , Molecular Sequence Data , RNA, Ribosomal, 16S/genetics , Species Specificity
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