Population Sampling (population + sampling)

Distribution by Scientific Domains


Selected Abstracts


The identity of Paeonia corsica Sieber ex Tausch (Paeoniaceae), with special reference to its relationship with P. mascula (L.) Mill.

FEDDES REPERTORIUM, Issue 1-2 2006
Hong De-Yuan
The taxonomy of the genus Paeonia in central Mediterranean islands has been controversial, with number of recognized taxa changing greatly from one species without infraspecific division to three species or five infraspecific taxa in one species, and with the number of synonyms as great as 30. In the present work, the taxonomic history is thoroughly reviewed and a taxonomic revision is made based on extensive field work, chromosome observation, population sampling, examination of a large amount of herbarium specimens, and subsequent statistic analysis. As a result of the studies P. corsica Sieber ex Tausch, an ignored specific name, is restored at specific rank, and the species is found distinct from all the three subspecies of P. mascula in this region in having mostly nine (vs , 10) leaflets/segments, shorter hairs (1.5 mm vs 3 mm long) on carpels, rather densely holosericeous (vs glabrous or very sparsely hirsute) on the lower surface of leaves. It is a diploid, confined to Corsica France), Sardinia (Italy), Ionian Islands and Akarnania Province of Greece, whereas P. mascula is a tetraploid, widely distributed from Spain to Turkey and Iraq, but not in Corsica, Sardinia and W Greece. In addition, type specimens of four taxa are designated, and 29 botanic names are listed as synonyms of P. corsica in this paper. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Die Identität von Paeonia corsica Sieber ex Tausch (Paeoniaceae), mit besonderem Bezug auf ihre Verwandtschaft mit P. mascula (L.) Mill. Die Taxonomie der Gattung Paeonia auf den zentralen Mittelmeerinseln ist stets kontrovers gewesen. Die Anzahl der Taxa wechselte zwischen einer Art ohne infraspezifische Differenzierung bis zu drei oder fünf infraspezifische Taxa innerhalb einer Art. Die Anzahl der Synonyme beträgt bis zu 30 Taxa. In vorliegender Arbeit wird die Geschichte der Taxonomie sorgfältig betrachtet und eine taxonomische Revision auf der Basis extensiver Feldstudien, Chromosomen-Bewertung, Sammlungen von Populationen, der Untersuchung zahlreicher Herbarproben und abschließender statistischer Analysen vorgenommen. Im Ergebnis dieser Untersuchungen wird Paeonia corsica Sieber ex Tausch, ein bislang unbeachteter Artname, erneut in den Rang einer Art erhoben. Diese in dieser Region gefundene Spezies wurde als verschieden von den drei Unterarten von Paeonia mascula befunden. Sie hat meist neun (, 10) Blättchen, kürzere Haare (1.5 mm vs 3 mm lang) auf dem Karpell dichtere holoserios (vs glabrous oder selten hirsut) auf der Blattunterseite. Paeoniacorsica ist diploid auf Korsika (Frankreich), Sardinien (Italien), den Ionischen Inseln und der Provinz Akarnania in Griechenland, während Paeonia mascula tetraploid ist und weit verbreitet von Spanien bis in die Türkei und den Irak, fehlt aber auf Korsika, Sardinien und in Westgriechenland. Außerdem werden Typspecimen für 4 Taxa festgelegt. Als Synonyme von P. corsica wurden 29 Namen aufgelistet. [source]


Population genetics suggests effectiveness of habitat connectivity measures for the European tree frog in Switzerland

JOURNAL OF APPLIED ECOLOGY, Issue 4 2009
Sonia Angelone
Summary 1.,Governmental authorities in many countries financially support the implementation of habitat connectivity measures to enhance the exchange of individuals among fragmented populations. The evaluation of the effectiveness of such measures is crucial for future management directions and can be accomplished by using genetic methods. 2.,We retraced the population history of the European tree frog in two Swiss river valleys (Reuss and Thur), performed comprehensive population sampling to infer the genetic structure at 11 microsatellite markers, and used first-generation migrant assignment tests to evaluate the contemporary exchange of individuals. 3.,Compared with the Thur valley, the Reuss valley has lost almost double the number of breeding sites and exhibited a more pronounced genetic grouping. However, similar numbers of contemporary migrants were detected in both valleys. In the Reuss valley, 81% of the migration events occurred within the identified genetic groups, whereas in the Thur valley migration patterns were diffuse. 4.,Our results show that the connectivity measures implemented in the Reuss valley facilitated effective tree frog migration among breeding sites within distances up to 4 km. Nevertheless, the Reuss valley exhibited high genetic differentiation, which reflected the impact of barriers to tree frog movement such as the River Reuss. By contrast in the Thur valley, a larger number of breeding sites have been preserved and high admixture indicated exchange of individuals at distances up to 16 km. 5.,Synthesis and applications. We show that genetic methods can substantiate the effectiveness of connectivity measures taken in conservation management at the landscape scale. We urge responsible authorities from both river valleys to continue implementing connectivity measures and to create a dense network of breeding sites, as spatial gaps of 8 km are rarely traversed by tree frogs. [source]


Prevalence of latex sensitization and allergy in Portuguese children

PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 6 2006
Arminda Jorge
The prevalence of latex allergy has been increasing not only in risk groups but also in the general population, where it is accepted to average 1%. In children, latex sensitization prevalence studies are scarce and involve different population sampling and allergy testing methods, which makes it difficult to compare across studies. Nevertheless, existing studies point towards a low prevalence of latex allergy in children, which still needs to be confirmed in the Portuguese population. Aiming at studying the prevalence of latex sensitization and allergy in a sample of Portuguese children, we studied 182 children from two different hospital outpatient clinics. A standardized questionnaire focusing on atopic background, previous history and allergic signs or symptoms on exposure to latex or fruits was given to all children and parents. Skin prick testing was performed with a battery of common aeroallergens as well as latex. Serum total IgE, Phadiatop, F × 5E and latex-specific IgE were determined in all children. Specific IgE to latex-crossreacting fruits was determined in latex-sensitized children. Based upon the questionnaire, the prevalence of latex allergy would be 0.5%. The prevalence of latex sensitization would be 3.8%, when based solely upon skin prick testing, and 12.1% (,0.35 IU/ml) or 6.6% (,0.70 IU/ml) when based singly upon determination of latex-specific IgE. When positive results for either test were considered, the prevalence of latex sensitization was 14.3%. All latex-sensitized children were atopic. Sensitivity to latex-crossreacting foodstuffs was demonstrated in 61.5% of latex-sensitized children (16/26). This study shows that the prevalence of latex allergy and sensitization in Portuguese atopic and non-atopic children, as analysed using various diagnostic methods, is similar to that observed in other countries. In addition, the assessment of latex allergy and sensitization should always include skin prick testing and determination of serum IgE. [source]


Paeonia (Paeoniaceae) in the Caucasus

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2003
DE-YUAN HONG
The taxonomy of the genus Paeonia in the Caucasus has been controversial, with recognized species varying in number from one to 13. The taxonomic history of Paeonia in this area is reviewed (including an analysis of the characters used by previous authors) based on extensive field observations, population sampling and critical examination of a large number of herbarium specimens. The results show that Paeonia may be divided into three groups. The P. intermedia group is known from only a single population. In the P. tenuifolia group, all the characters used for distinguishing the three previously recognized species were found to be polymorphic. In the P. daurica group, petal colour, shape and size of leaflets, and indumentum of leaflets and carpels were used to distinguish nine species, but these characters were found to be polymorphic or continuous in variation, and thus can only be used for infraspecific classification. Thus, three species are recognized: P. intermedia, P. tenuifolia and P. daurica. The last species is further divided into five subspecies: sspp. coriifolia, wittmanniana, mlokosewitschii, macrophylla and tomentosa stat. nov. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 143, 135,150. [source]