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1.
The population of white-tailed sea eagles (Haliaeetus albicilla) in the Czech Republic declined dramatically during the twentieth century. None were observed in the area for more than 60 years until population recoveries were observed beginning in the 1980s. It is currently estimated that 25–30 breeding pairs of white-tailed sea eagles nest in the Czech Republic. This article analyses surveillance data from three periods between 1973 and 2003 on the occurrence and nesting of white-tailed sea eagles in the Czech Republic. We investigated recolonization of European white-tailed sea eagles in the Czech Republic in terms of migration patterns and population structures. Bird ringing data suggest the Czech population may be recovered from various areas encompassing northern Europe. Using data collected by DNA microsatellite, no population structure was revealed through Bayesian and cluster analyses with an existing Hardy–Weinberg equilibrium, which suggests mixed panmictic populations of white-tailed sea eagles in the Czech Republic and Slovakia. While analysis of genetic diversity showed no difference between recovered populations in the southeastern Czech Republic and those persisting in Slovakia, there was genetic diversity between eagles of the southeastern subpopulation and eagles in other parts of the Czech Republic. Taken together, these observations on the population structure of white-tailed sea eagles in the Czech Republic imply that other European birds contributed to the recovery of the Czech population, likely through breeding mixture with an identifiable centre in the southeastern Czech Republic.  相似文献   

2.
ABSTRACT

The Roma represents a transnational ethnic group, with a current European population of 8–10 million. The evolutionary process that had the greatest impact on the gene pool of the Roma population is called the founder effect. Renal hypouricemia (RHUC) is a rare heterogenous inherited disorder characterized by impaired renal urate reabsorption. The affected individuals are predisposed to recurrent episodes of exercise-induced nonmyoglobinuric acute kidney injury and nephrolithiasis. To date, more than 150 patients with a loss-of-function mutation for the SLC22A12 (URAT1) gene have been found, most of whom are Asians. However, RHUC 1 patients have been described in a variety of ethnic groups (e.g., Arab Israelis, Iraqi Jews, Caucasians, and Roma) and in geographically noncontiguous countries. This study confirms our previous findings regarding the high frequency of SLC22A12 variants observed. Frequencies of the c.1245_1253del and c.1400C>T variants were found to be 1.92% and 5.56%, respectively, in a subgroup of the Roma population from five regions in three countries: Slovakia, Czech Republic, and Spain. Our findings suggested that the common dysfunction allelic variants of URAT1 exist in the general Roma population and thus renal hypouricemia should be kept in differential diagnostic algorithm on Roma patients with defect in renal tubular urate transport. This leads to confirm that the genetic drift in the Roma have increased the prevalence of hereditary disorders caused by very rare variants in major population.  相似文献   

3.
豆科紫藤属Wisteria约有5-6个现生种,间断分布于中国、日本和美国的温带地区,但化石记录表明,该属在新近纪可能广泛分布于捷克、荷兰、格鲁吉亚阿布哈兹、保加利亚、罗马尼亚、俄罗斯远东、日本和中国。因此,研究紫藤属化石有助于深入认识它的早期演化、分类、多样性、古生态和生物地理,其中荚果化石的分类价值和演化意义尤为显著。文中基于对产自山东临朐中中新世山旺组的山旺紫藤W.shanwangensis荚果化石的再观察,并结合紫藤属3个现生种——紫藤W.sinensis、藤萝W.villosa和多花紫藤W.floribunda的荚果发育特征,讨论这些化石的分类、演化、发育和埋藏学意义。结果进一步证明,山旺紫藤荚果化石与国产的2个现生种——紫藤和藤萝的荚果更为相似,呈倒披针形、种子较少和室间缢缩明显。比较而言,日本和美国产的紫藤属现生种——多花紫藤和美国紫藤W.frutescens的荚果呈线形、种子较多和室间缢缩不明显,而且日本中新世和上新世报道的紫藤属荚果化石与多花紫藤的荚果更为相似。然而,中国和日本报道的紫藤属荚果化石迄今都没发现被毛,这与现生种中最原始的美国紫藤的荚果相似,而与东亚紫藤属现生种密被绒毛的荚果形成显著差别。因此,中国、日本和美国的紫藤属种类可能早在中新世就已经发生了形态地理分化,而荚果无毛或许是该属演化过程中一个比较原始的性状;紫藤属现生种荚果在发育的中、后期果壁上具有与纵轴方向成锐角的倾斜纤维纹饰,它们在荚果完全成熟后导致果瓣沿缝线开裂并卷曲,卷曲的果瓣放入水中又能恢复平整。值得注意的是,山旺紫藤荚果化石果壁上也发现了类似的倾斜纤维纹饰,这表明它们在脱落保存时处在发育的中、后期,这一发育时期脱落的荚果更有可能保存为化石记录;山旺紫藤荚果化石果壁的碳质残片中还富含硅藻类,近似于远距直链藻Melosira distans和颗粒直链藻M.granulata这些浮游相的、生活在深水区的优势种。因此,山旺紫藤荚果脱离母体后可能沉积在湖水较深的地方,而且它也可能是在成熟开裂的状态下脱落,瓣片本来卷曲,被短程搬运至湖中,又在湖水的浸泡下恢复平整状态,而后经沉积物掩埋后形成化石。  相似文献   

4.
On 6-9 May 1985, an international conference on "Children in the information age," organized by the State Committee on Science and Technical Progress of the People's Republic of Bulgaria, was held in Varna, Bulgaria. Among the participants were [representatives of] the International Institute of Applied Systems Analysis (Austria), UNESCO, the International Fund of Ludmila Zhivkova (People's Republic of Bulgaria), and the World Health Organization. The purpose of the conference was to exchange experience on current problems in the computerization of learning, computer literacy, and information sciences in schools. About two hundred scientists from 45 different countries took part in the conference. The results of studies of methodological, psychological, pedagogical, physiological, and technical aspects of the problem of computerization of learning were discussed at plenary and workshop sessions. In addition, a special exhibit acquainted people with modern computer teaching devices, microprocessor teaching technology, dialogue teaching systems, logical and algorithmic games, programs, etc.  相似文献   

5.
In this paper, activity concentrations of radiocesium in mushrooms from various locations in the Czech Republic and the Slovak Republic in the years 2000–2004 are presented. Summary reports of Czech regulatory bodies have judged the average activity concentrations in mushrooms to be remarkably below the maximum permissible level of contamination. However, there are certain regions where radiocesium activities have approached the maximum permissible level for contamination of basic foodstuff. For example, the highest activity concentration of 137Cs measured by gamma-spectrometry was 2,263 Bq kg−1 (on a dry mass basis), in Xerocomus badius from Staré Ransko (a locality in the Czech-Moravian Highlands, Czech Republic). The highest activity concentration of 137Cs measured in Slovakia was 966 Bq kg−1 (on a dry mass basis), for Suillus luteus from Senica. For comparison, the corresponding activity concentration in a sample taken within the 30 km zone around Chernobyl was measured to be 6,000 Bq kg−1 (on a dry mass basis). Our results have also demonstrated remarkably lower activity concentrations of 137Cs in Slovakia compared to those in the Czech Republic.  相似文献   

6.
Brachycaudus divaricatae (Hemiptera: Aphididae), a recent invader to Europe, has already reached Czech Republic. Partial sequences of mitochondrial COI and nuclear EF-1α genes have been analysed across the sixteen Czech samples of B. divaricatae, together with morphometric analysis of the same samples based on eighteen morphological characters of the apterous viviparous females. For comparative studies, thirteen samples from the Eastern Baltic region of Europe (Latvia, Lithuania and Poland) were used. All sampled populations appeared similar in their genetic and morphological characters studied. One haplotype of mitochondrial COI gene was predominant; it was characteristic for all samples from Czech Republic and 8 out of 13 samples from Eastern Baltic region. Two other haplotypes were found in the Eastern Baltic region only. Four different haplotypes of EF-1α gene were detected. Most of the samples (except one sample from the Eastern Baltic region and two samples from Czech Republic) had the same haplotype. Out of remaining three haplotypes, one was unique for the Eastern Baltic region, whilst two were found in Czech Republic only. For the present, Moravia is the southernmost region in Europe, where B. divaricatae has been already reported. Presumably, this invasive aphid species has entered the Czech Republic from the north via the Moravian Gate, a natural pass formed by the depression between the Western Carpathians and Eastern Sudetes.  相似文献   

7.
Abstract: Aphidius colemani Vier. (a Chilean strain) was introduced and became established in the field between 1992 and 2000 in the Czech Republic. The target aphid species, Aphis spiraephaga Muell. on Spiraea ornamentals, and later the Russian wheat aphid, Diuraphis noxia (Kurdj.) on small grains were found parasitized, but an increasing number of other host aphid species in various urban ecosystems, crops and native communities was also detected. The establishment of A. colemani is classified as positive in supplementing the native parasitoid guilds as well as in contributing to the overall biodiversity of hymenopterous parasitoids in the cultivated landscape.  相似文献   

8.
9.
The distribution and ecology of four threatened lichens in the Czech Republic, Evernia mesomorpha, Hyperphyscia adglutinata, Hypotrachyna revoluta and Parmotrema perlatum, have been studied. All species are mainly epiphytic, but recent records from the Czech Republic are largely from siliceous rocks in river/brook valleys. Changes in distribution and substrate preferences are documented and discussed.  相似文献   

10.
Sika deer (Cervus nippon), native to Asia, formed two well-established free-living populations in the Czech Republic over the last century and continue to spread. Sika are also maintained in a large number of enclosures; these continue to introduce new individuals from the places of its origin as well as from other European countries. Despite extensive research into the morphology and ethology of the Czech sika deer, conducted over the last three decades, no study using genetic methods has been done. This study aimed to determine the genetic variability and the geographic origin of the Czech sika deer population. Two mitochondrial markers, the cytochrome b and the control region were analyzed in this study. Analysis of the two markers confirmed that the founder individuals of the Czech population originated from both native island (Japanese Islands) and native mainland (Far East Russia) populations. Results showed that the genetic variability of the Czech sika deer population is lower than the variability of the native Japanese population, but higher than that of the sampled part of the native Russian population. Also, the genetic variability was found to be higher within the samples from enclosures.  相似文献   

11.
The sequences of the 3′‐terminal region of four Czech Potato virus M isolates VIRUBRA 4/007, VIRUBRA 4/009, VIRUBRA 4/016 and VIRUBRA 4/035 were determined and compared with sequences of PVM isolates available in GenBank. Among the Czech isolates, VIRUBRA 4/007 and 4/016 as well as VIRUBRA 4/016 and 4/035 showed the highest nucleotide identity (93%). Isolates VIRUBRA 4/007, 4/016 and 4/035 were most similar to the PV0273 isolate from Germany and to the wild isolate from Russia. Interestingly, isolate VIRUBRA 4/009 significantly differed from the other three Czech isolates and was the only European isolate that showed the highest nucleotide identity with American isolates. Moreover, the PVM isolates from the Czech Republic and Germany differed in their host range. Phylogenetic analysis based on ORF5 coding for coat protein showed that the Czech isolates could be classified in two of the three groupings of the phylogenetic tree obtained. This is the first report on molecular and biological analysis of the genome sequences of PVM isolates from the Czech Republic.  相似文献   

12.
The 1997 check list of Dolichopodidae of the Czech Republic and Slovakia has recently been reviewed and updated. The new species list includes 346 species with 22 species added as new to the fauna of the Czech Republic. While the check list itself is published elsewhere, largely unpublished new records of Hercostomus argentifrons, H. nigrilamellatus, Medetera adjaniae, M. melancholica and M. setiventris are presented here, together with data on their distribution in Europe and their biology and ecology. The status of the newly added Sympycnus desoutteri is discussed. H. argentifrons is recorded here for the first time from the Czech Republic (Bohemia; Moravia) and background information is given on its discovery. While the Czech fauna with 324 species can be considered well known, the fauna of Slovakia is definitely much richer than its current national list of 217 species suggests. In the latter country, in particular surveys of sandy habitats with heathland or peatmoor, saltmarshes, reedmarshes, humid forests on loamy soils, and of rothole and saprun microhabitats on trees might quickly yield new species records.  相似文献   

13.
The problem of HIV infection spread in Russian Federation is examined in the article. Data on HIV infection dynamics and predominate risk groups of the population during different years are presented. Age structure of HIV infected individuals in Russian Federation is examined. Main factors that promote HIV infection spread in Russian Federation are specified and means of control are proposed.  相似文献   

14.
Invasive organisms represent great threats to ecosystems and great challenges to forest management. In Europe, the black timber bark beetle (Xylosandrus germanus) is an invasive secondary pest that mostly attacks the logs of felled trees. We showed the invasion history for Europe and using many local surveys, we summarize the current distribution and other available information on X. germanus in the Czech Republic. We report that this species is distributed from the lowlands to the mountains in the Czech Republic; it is widespread in the eastern half of the country, where it is more abundant in the warmer south and southeast areas than in the cooler areas. Most (78%) of the known localities are at elevation below 400 m a.s.l. Although an ice storm greatly increased X. germanus abundance near the border with Austria, its high abundance did not result in damage to standing trees. Presence of X. germanus in the Czech Republic for over 10 years has not led to heavy tree infestation.  相似文献   

15.
According to the data, presented by the author and based on the study of opinions expressed by HIV-infected persons, 80% of them are subjected to discrimination. The article deals with the problem of the legal protection of HIV-infected persons in the Russian Federation. Additions and changes in the current legislation regarding foreign citizens and persons in places of confinement are proposed.  相似文献   

16.
Tomáš Grim 《Biologia》2006,61(2):235-239
Despite being considered a classical example of protective Batesian mimicry hoverflies (Syrphidae) are known to be preyed upon by various passerines. The aim of the present study was to examine in detail food brought by reed warblers Acrocephalus scirpaceus to their nests to better understand the importance of hoverflies in the diet of small passerines. Using neck collars, 273 food samples containing 8,545 food items delivered to reed warbler and parasitic common cuckoo Cuculus canorus nestlings in warbler nests were recorded. The study was conducted during three breeding seasons in South Moravia, Czech Republic. An unusually high diversity of hoverflies was found — 27 species, including Mesembrius peregrinus (critically endangered species in the Czech Republic) and Mallota cimbiciformis (endangered species) — a new taxon to the Czech Republic. This indicates that nestling diet analyses may provide not only information on avian foraging behaviour but also important faunistic data. Thus, without the detailed identification to species level of material from foraging behaviour studies valuable scientific information may be lost. Overall dominance of Syrphidae was 3.7%, the most common species being Episyrphus balteatus (55.7%, n = 318). However, this number seriously underestimates the importance of hoverflies in the diet of reed warblers as hoverflies are one of the largest prey taken by warblers. Both larvae and pupae were rare, imagines strongly dominating (92.7%). Both specific wasp mimics (e.g., Chrysotoxum verrali) and bee mimics (e.g., Eristalis spp.) were not avoided by foraging reed warblers. The presence of a parasitic cuckoo chick did not affect host foraging behaviour with respect to overall dominance of hoverflies in the diet (warbler 3.3%, cuckoo 3.8%).  相似文献   

17.
Two species of Tatria Kowalewski, 1904 are redescribed from grebes in Bulgaria: T. biremis Kowalewski, 1904 (specimens from Podiceps nigricollis) and T. minor Kowalewski, 1904 (specimens from P. cristatus and P. nigricollis). T. mircia Gulyaev, 1990 is synonymised with T. minor. The previous records of T. biremis, T. minor and T. mircia are critically analysed in view of the present results. T. gulyaevi n. sp. is described from P. nigricollis from Bulgaria and the Czech Republic and from an unidentified grebe species from Turkey. Some of the previous records of T. minor and T. biremis are recognised as belonging to T. gulyaevi. One specimen illustrated by Kowalewski (1904) is designated as a lectotype of T. minor in order to stabilise the nomenclatural standing of this species.  相似文献   

18.
19.
Chromosome numbers forEleocharis palustris subsp.palustris (based on 70 samples from Austria, Bulgaria, Croatia, the Czech Republic, Germany, Greece, Hungary, Lithuania, Romania, Russia, Slovakia, Slovenia, and Sweden) andEleocharis palustris subsp.vulgaris (based on 74 samples from Austria, the Czech Republic, Denmark, Germany, Ireland, Latvia, Luxembourg, the Netherlands, Portugal, and Sweden) are given. Also the chromosome number estimates based on relative DNA contents of plants from 8 localitiesE. palustris subsp.palustris from Croatia, the Czech Republic, Germany, Italy, Israel, and Slovenia, and from 18 localities ofE. palustris subsp.vulgaris from the Czech Republic, Germany and Sweden are included. InE. palustris subsp.palustris, 2n=16 prevailed, the mixoploid 2n=15, 16 was rare and a lone hypoploid 2n=15 was detected. InE. palustris subsp.vulgaris 2n=38 was most frequently detected, the hyperploid 2n=39 and mixoploid 2n=38, 39 were common, and the hypoploid 2n=36 and mixoploids in which 2n ranges from 36 to 42 were rarer. Distribution maps based on plants investigated either by chromosome counting or by flow cytometry, augmented by similar data from published sources are given for both subspecies in Europe.  相似文献   

20.
A comparative analysis was performed on sixteen morphometric characters, in three different juvenile sterlet Acipenser ruthenus L. populations. Specimens were collected from a wild population in the Serbian part of the Danube River (n = 46), from aquaculture stocks in the Czech Republic originating from Russia (n = 40), and aquaculture stocks in the Slovak Republic originating from Slovakian part of the Danube River (n = 28). Average values for total length were 29·9 ± 3·9 cm, 29·1 ± 3·7 cm and 27·3 ± 7·7 cm for Serbia, Czech Republic and Slovak Republic, respectively. Populations were compared using t‐test and sequential Bonferroni correction for multiple comparisons was applied in order to determine significant differences between them. Results of analysis showed that all three populations differed in prebarbel length, interocular distance and maximum head width. Although all these characters are head‐related, head length itself was very uniform among all populations. The natural population from the Serbian part of the Danube River differed from the populations reared in aquaculture in seven morphometric characters. The two populations reared in aquaculture consistently showed lower morphological variability than the wild population, even though they had different genetic backgrounds (Russia and Slovakia). Future genetic studies will show if this tendency is caused by a reduction in genetic variability.  相似文献   

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