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1.
Background: Taxonomic analysis provides a basic understanding for taxon identification and contributes to preliminary information for several branches of applied biology, while studies on reproductive strategies and plant fitness are essential to interpret population status and dynamics.

Aims: We tested the reliability of diagnostic characters for identification and to characterise sexual resource allocation, the breeding system and seed predation among subspecies of Gentiana lutea.

Methods: We analysed morphological characters in 70 herbarium specimens. In five natural populations we counted pollen and ovule numbers, assessed reproductive output after pollination treatments and evaluated pre-dispersal predation.

Results: Taxonomic traits previously indicated as diagnostic were not sufficient to discriminate among subspecies. The pollen number and pollen:ovule (P:O) ratio varied strongly among subspecies; self-pollinated flowers produced a significantly lower number of seeds than open-pollinated flowers. Retention of empty fruits and high levels of pre-dispersal seed predation were observed in every case.

Conclusions: The variation of P:O ratios among subspecies suggests different efficiency in pollen transfer. The species is self-compatible, nevertheless all subspecies require pollen vectors to enhance cross pollination and viable seed production. Fruit retention may have evolved as a strategy to reduce predation, ensuring higher plant fitness.  相似文献   


2.
Capsule: Northern Lapwing Vanellus vanellus avoid nesting close to small woodland patches but nest predation rates do not vary with distance to woodland patches, either because risky areas are avoided or perceived nest predation risk does not reflect actual risk.

Aims: To explore the effects of woodland patches in wet grassland landscapes on nest distribution and success of Lapwings.

Methods: We quantified the effect of woodland patches on the distribution and outcome of Lapwing nests across four wet grassland sites by mapping nest distribution and monitoring nest outcomes.

Results: Lapwing nested significantly further from woods than expected by chance. Neither nest predation rates nor the probability of predation occurring at night (thus primarily mammalian predators) or day (primarily avian predators) varied in relation to distance from woodland patches.

Conclusions: High levels of nest and chick predation in wet grassland landscapes limit the capacity for breeding wader populations to be self-sustaining. Consequently, identifying manageable landscape features that influence predation rates is an important focus of conservation research. Lapwing avoid breeding close to woodland but, as nest predation rates do not vary with distance from woodland patches, their removal may increase the area of suitable nesting habitat but is unlikely to substantially influence productivity.  相似文献   


3.
Capsule: The diet of Black Guillemot Cepphus grylle grylle chicks in the Baltic Sea region was dominated by Viviparous Eelpout Zoarces viviparus. Risk of nest predation by avian and mammalian predators was perceived to be low, and hatching and fledging success were high.

Aims: To gain insight into the ecology of nestling Black Guillemots in the Baltic Sea region to fill knowledge gaps and benefit its conservation.

Methods: Two island groups in the Baltic Sea were visited several times during the breeding season of 2014 and 2015 to monitor nestling survival and fledging. In addition, camera traps were used in 2014 to monitor prey brought to chicks by adults and record possible nest predation events.

Results: Hatching success was 0.89 and 0.73 in 2014 and 2015, respectively, and fledging success was very high (0.95 and 0.97). No incidences of avian or mammalian predation were observed. Chicks fledged at night between 32 and 38 days after hatching. Viviparous Eelpout made up 95% of the prey items brought to the chicks by adults.

Conclusions: The hatching rate and fledging rate of the Black Guillemot was high in our study region. Juveniles seemed highly dependent on the availability of eelpout. Changes in the abundance of this species may therefore have negative effects on chick survival.  相似文献   


4.
Capsule The analyses support the grouping of the three Acanthis species, although a large split is observed between the A. hornemanni subspecies.

Aims To investigate the morphological variation in A. f. islandica among different periods of the year and its morphological differentiation from the other subspecies A. f. flammea and A. f. rostrata, and also from the redpoll species, A. cabaret and the two subspecies of A. hornemanni, exilipes and hornemanni.

Methods The subspecies status of the Icelandic population was evaluated with Amadon's rule, by comparing its variation of traits to the distribution of the traits in different species/subspecies of the group.

Results A. f. islandica is characterized by intermediate wing, bill and tail lengths. Based on the 75% rule, wing length and bill depth can be used to discriminate A. f. islandica from both extreme morphs of redpolls (currently classified as different species); A. hornemanni and A. cabaret, and tail and wing length can distinguish A. f. islandica from its conspecifics A. f. flammea. The overall morphological divergence within the redpoll complex is not supported by association to the studied nuclear markers.

Conclusion The taxonomic status of the three redpoll species is supported by Amadon's rule, however the subspecies status of the Icelandic Redpoll remains unclear.  相似文献   


5.
Introduction. We found an unusual specimen collected in 1975 from Xinjiang Province, China which may represent Grimmia exquisita J.Muñoz. However, this species is known only from the type localities and its taxonomic status is still controversial.

Methods. A voucher of the Chinese specimen is deposited in IFP herbarium. This specimen was studied with the typical anatomical and morphological methods applied within Grimmia (Maier, 2010).

Key Results. The Chinese species represents G. exquisita. After examining the type specimens of G. exquisita, we confirmed that it should be recognised as a distinct species.

Conclusions. This study expands the distribution area of G. exquisita to East Asia. The Chinese specimen was discovered in a rather different habitat to its types and consequently, G. exquisita may be a more widely distributed species. Evaluation of the Grimmia specimens in many different herbaria is needed.  相似文献   


6.
Capsule: Predation rates of artificial nests along elevational gradients were higher closer to the treeline in the European Alps.

Aims: Alpine grassland birds tend to show an avoidance of mature trees, possibly due to an edge effect, such as higher predation pressure close to the treeline. This study aimed to estimate potential predation pressure in relation to the distance from the treeline and other environmental variables by using artificial nests positioned along elevational transects in the Italian Alps.

Methods: A total of 119 artificial nests were positioned and monitored during the breeding season. For each nest, habitat data at small and large scales were collected. Daily nest survival was estimated using MARK.

Results: The most informative model included date, distance from the treeline and a micro-habitat structure variable. In particular, the model showed a positive relationship between nest survival and the distance from the treeline.

Conclusions: This study suggests that if treelines advance due to climate change, the functional habitat loss may be greater than physical habitat loss, since the optimal breeding area would be further away from the forest edge. The conservation of high-elevation grasslands in relation to environmental changes may therefore be addressed through management strategies to maintain open habitats.  相似文献   


7.
Capsule: Although survival of nests was similar between forest fragments and continuous forest, the range of predators differed. Artificial nests provide an under-estimate of nest predation by snakes.

Aims: To estimate the natural nest predation rate in continuous primary forest, compare it with predation rates in forest fragments. To assess the reliability of nest survival rates determined by the use of artificial nests with clay eggs and identify the main nest predators.

Methods: We observed survival of natural nests during the incubation period in continuous primary forest in Papua New Guinea. Some nests were monitored with infrared cameras. We also used artificial nests deployed with clay eggs to identify predators.

Results: There was a predation rate of 50% for natural nests and snakes were major predators of nest contents. Clutch daily survival rates (DSRs) differed among nest types. The DSR of artificial nests (0.977) was not significantly different to that of natural cup nests (0.969). Survival rates of artificial nests were similar in forest fragments and continuous forest. Forest fragments had, however, a higher proportion of avian predators than continuous forest.

Conclusion: Although, we observed similar survival rates in artificial and natural nests, the composition of nest predators was different between natural and artificial nests. Artificial nests were not suitable for estimating the real predation caused by reptiles. Nevertheless, we find that participation of avian nest predators can be estimated correctly with the use of artificial nests.  相似文献   


8.
The present study deals with four Chinese camaenid species based on museum collections and newly obtained materials. Pseudiberus liuae Wu, n. sp., diagnosed by two long mucous glands and the smallest shell size in the genus and inhabiting bare rock like other congeneric members, is described from southern Gansu. Aegista (Plectotropis) wardi (Preston, 1912) is conchologically re-described and moved out of Aegista Alber, 1860 to Pseudiberus Ancey, 1887 based on the keeled periphery and the absence of hairs, scales or their scars on the teleoconch, which are present in Aegista but partially absent in Pseudiberus. The first Chinese fluorescent snail Bradybaena qixiaensis Wu & Asami n. sp. is reported from Nanjing, Jiangsu. The species shares many characters with the Japanese fluorescent snail Bradybaena pellucida Kuroda & Habe, 1953 but is distinct in the pattern of microsculpture on the internal surface of the penis. Nesiohelix yeni Wu & Asami n. sp., sympatric with N. moreletiana (Heude, 1882), is distinguished from its congener by possession of a bubble-shaped penial caecum.

Pseudiberus liuae Wu in Wu & Asami, In Press

LSID urn:lsid:zoobank.org:act:3C9299AA-5089-4E43-9B26-85A0D6C23B66

Bradybaena qixiaensis Wu & Asami, In Press

LSID urn:lsid:zoobank.org:act:7991C4D5-5E0B-46DF-8B19-BE26511806CD

Nesiohelix yeni Wu & Asami, In Press

LSID urn:lsid:zoobank.org:act:68CFF173-AACC-4DA8-B347-9ABB5CA569A3  相似文献   


9.
Context: Genetics play a major role in development and pathophysiology of Type 2 diabetes mellitus (T2DM).

Objective: To asses the association of Guanine nucleotide-binding protein (GNB3) (C825T) gene's polymorphism with T2DM.

Materials and methods: A case–control study including 400 North Indians was performed using Polymerase Chain Reaction–Restriction Fragment Length Polymorphism (PCR-RFLP) approach to analyze genetic polymorphism.

Results: No significant difference was observed in genotype and allele frequencies of GNB3 gene on comparing cases with controls.

Discussion: Our study is in agreement with studies on Polish, Japanese, Hispanic-American and Danish populations who observed no significant association between GNB3 (C825T) polymorphism and T2DM.

Conclusion: GNB3 (C825T) polymorphism is not associated with T2DM.  相似文献   


10.
Context: Drugs such as positive allosteric modulators (PAMs) produce complex behaviors when acting on tissues in different physiological contexts in vivo.

Objective: This study describes the use of functional assays of varying receptor sensitivity to unveil the various behaviors of PAMs and thus quantify allosteric effect through system independent scales.

Materials and methods: Muscarinic receptor activation with acetylcholine (ACh) was used to the demonstrate activity of the PAM agonist 1–(4-methoxybenzyl)-4-oxo-1,4-dihydroquinoline-3-carboxylic acid, Benzyl quinolone carboxylic acid (BQCA) in terms of direct agonism, potentiation of ACh affinity, and ACh efficacy. Concentration–response curves were fit to the functional allosteric model to yield indices of agonism (τB), effects on affinity (α cooperativity), and efficacy (β cooperativity).

Results: It is shown that a highly sensitive functional assay revealed the direct efficacy of BQCA as an agonist and relatively insensitive cells (produced by chemical alkylation of muscarinic receptor with phenoxybenzamine) revealed a positive allosteric effect of BQCA on ACh efficacy. A wide range of functional assay sensitivities produced a complex pattern of behavior for BQCA all of which was accurately quantified through the system-independent parameters of the functional allosteric model.

Conclusions: The study of complex allosteric molecules in a range of functional assays of varying sensitivity allows the measurement of the complete array of activities of these molecules on receptors and also better predicts which will be seen with these in vivo where a range of tissue sensitivities is encountered.  相似文献   


11.
Upon a thorough investigation, it has been determined that the paper titled “Integrating Microbial Composting and Vermicomposting for Effective Utilization of By-Products of Sugar Cane-Processing Industries” by Shweta, Rahul Kumar, B.L. Singh, and Verma Deepshikha published in the Bioremediation Journal, 2010, Volume 14, pages 158–167, was simultaneously submitted and published in two journals. The same study with minor textual variations titled “Composting of sugar-cane waste by-products through treatment with microorganisms and subsequent vermicomposting” also written by Shweta, Rahul Kumar, B.L. Singh, and Verma Deepshikha published in the Elsevier publication, Bioresource Technology, 2010, 6707–6711, three months prior to publishing in Bioremedation Journal.

As a result the article published in Bioremediation Journal has been retracted and should not be cited in the electronic or print version of the journal.

Dr. Hanadi S. Rifai

Editor-in-Chief

Bioremediation Journal

Please click here to view the article to which this statement of retraction relates.  相似文献   


12.
Context: Three-dimensional tumor spheroid cultures are a better representative of in vivo solid tumors than monolayer cultures and should be used for testing potential nanotherapeutics in vitro.

Objective: To develop techniques to test the disposition and efficacy of nanocarrier formulations in spheroids in a cost-effective manner amenable to high-throughput testing.

Methods: Spheroids were obtained using a modified liquid overlay technique in a 96-well plate. Several nanocarrier formulations were prepared and tested in the spheroid model. The disposition of the formulations in the spheroids was determined by confocal microscopy while the effect of the drug-loaded formulations was assessed in terms of the cell viability, loss of membrane integrity, induction of caspases and inhibition of growth of the spheroids.

Results: The surface charge of the formulations influenced the accumulation of the nanocarrier and drug in the spheroid, with the cationic formulation accumulating to the greatest extent. Also, the smallest particle size formulation, micelles, penetrated to the greatest extent in the spheroid. The iRGD tumor-penetrating peptide co-administered with unmodified liposomes exhibited both high accumulation and penetration. The effect studies revealed that the formulations that penetrated or accumulated to the highest extent in the spheroid exhibited better antitumor activity compared to the other formulations.

Conclusion: The 96-well plate format spheroid model developed in the study can be used toward the rational selection of nanocarrier therapeutics prior to their testing in in vivo models.  相似文献   


13.
Context and objective: To evaluate if YKL-40 can provide prognostic information in patients with ischemic heart failure (HF) and identify patients who may benefit from statin therapy.

Materials and methods: The association between serum YKL-40 and predefined outcome was evaluated in 1344 HF patients assigned to rosuvastatin or placebo.

Results: YKL-40 was not associated with outcome in adjusted analysis. In YKL-40 tertile 1, an effect on the primary outcome (HR 0.50, p?=?0.006) and CV death (HR 0.54, p?=?0.040) was seen by rosuvastatin in adjusted analysis.

Conclusions: A beneficial modification of outcome was observed with statin therapy in patients with low YKL-40 levels.  相似文献   


14.
Capsule: The diversity of mammal hair found in nest linings varied between bird species and with season.

Aims: We examined mammal species composition in the guard hair material of four cavity-nesting songbirds, focusing on their numbers and occurrence, nest predation and seasonality.

Methods: We surveyed 219 nests of four cavity-nesting songbirds breeding in a Central European woodland and identified hairs from 28 mammal species.

Results: Roe Deer Capreolus capreolus hair was the most commonly used hair type in the nests of all four songbird species. This was especially the case in Blue Tit Cyanistes caeruleus nests, which may suggest a preference for Roe Deer hair. The greatest diversity of hairs was found in the nests of Great Tits Parus major, while the lowest was found in the Collared Flycatcher Ficedula albicollis. In flycatchers, 59% of females used only plant material for nest construction. Interestingly, we found a strong seasonal effect in hair use. Flycatcher nests that were initiated early in the season were more likely to contain mammal hair than those initiated later in the season. Similar, albeit weaker, negative seasonal effect was detected in Great and Blue Tit nests. There were no significant effects of any potential anti-predatory functions of mammalian hair in nests.

Conclusion: Our study showed a clear prevalence of Roe Deer in the hair material of all bird species and certain preferences of birds for particular mammal species. When the aim is to detect a wide range of mammal species, for example, during biodiversity surveys, we advise to consider sampling effort and to focus on early breeding birds.  相似文献   


15.
Capsule All British Marsh Tits belong to subspecies Poecile palustris dresseri, being smaller than nominate P. p. palustris of central Europe.

Aims Determining the subspecies of Marsh Tit in Britain to test whether ssp. P. p. palustris occurs in northern England and Scotland, by assessing regional variation in size compared with central European birds.

Methods 1147 wing length and 250 tail length measurements from 953 Marsh Tits were compared between eight British locations to test for regional variation. Biometrics were compared between birds from Britain and six locations within the continental European range of ssp. palustris.

Results There was no regional variation in wing or tail lengths among British Marsh Tits, indicating that all resident birds belong to ssp. dresseri. There was no evidence supporting the existence of ssp. palustris in northern England. British birds were significantly smaller than those from continental Europe, with proportionately shorter tails, consistent across all age and sex classes.

Conclusion All British Marsh Tits should be considered as ssp. dresseri, with ssp. palustris being limited to continental Europe. With no evidence of regional variation in size within Britain, reliable sexing methods based on biometrics could be applied in demographic studies throughout the country.  相似文献   


16.
Capsule: There is low genetic diversity in the Macqueen’s Bustard Chlamydotis macqueenii in Iran.

Aims: To investigate the genetic diversity and population structure of Macqueen’s Bustard in Iran, using two mitochondrial DNA loci.

Methods: Molecular diversity of the mitochondrial cytochrome oxidase c subunit I (COI) gene and part of the mitochondrial control region D-loop (in total 1183 base pairs) were analysed from 26 individual Macqueen’s Bustards from three regions of Iran.

Results: There was little variation in nucleotides and haplotypes in the populations for genes of both CR and COI. The population had free breeding and gene flow between the three study regions in Iran: Petregan, Ferdows and Yazd.

Conclusion: The use of molecular and genetic studies is essential to strengthen the protection of genetic diversity of the Macqueen’s Bustard.  相似文献   


17.
Capsule: There were only weak effects of winter flooding episodes on apparent annual survival of a White-throated Dipper breeding population in northern Iberia.

Aims: To test whether extreme winter flooding episodes affected survival in a breeding population of White-throated Dippers Cinclus cinclus.

Methods: Dippers were ringed during the breeding seasons of seven consecutive years on rivers in northern Iberia. Cormack–Jolly–Seber models were used to estimate apparent annual survival in relation to flooding during the winter periods.

Results: We obtained weak evidence for an effect of flooding during the winter on the surveyed population. Two of the six winters were characterized by having an exceptionally high discharge. Our models showed that survival in the subsequent breeding period tended to be lower, although models assuming constant survival were equally well supported.

Conclusion: Extreme flooding in winter may affect survival of some White-throated Dippers in northern Iberia, but its impact at the population level seems to be weak.  相似文献   


18.
Capsule: There are significant biometric differences between Pied Flycatchers from Iberian and north African populations which are consistent with proposals to classify the two forms into separate species.

Aims: To determine the similarities and differences in the main biometrical and plumage sex traits between populations of the Iberian Pied Flycatcher Ficedula hypoleuca iberiae and the Atlas Flycatcher Ficedula hypoleuca speculigera.

Methods: Biometric and plumage traits of 193 breeding individuals of Iberian Pied Flycatchers and 43 Atlas Flycatchers were measured in 2014 with standardized protocols.

Results: Both sexes of Atlas Flycatchers were larger than Iberian Pied Flycatchers in skeletal (tarsus) and wing size and also differed in bill morphology, which was wider but shallower in speculigera than iberiae, with females (but not males) having shorter bills than iberiae females. Males differed in mantle colour and forehead patch size, with speculigera males being darker and displaying larger forehead patches than iberiae males. As in populations of iberiae, some speculigera females also expressed a white forehead patch.

Conclusion: We demonstrate significant phenotypic differences between Iberian Pied Flycatchers and Atlas Flycatchers with respect to size and traits of ecological and evolutionary relevance, supporting the recently proposed scenarios on their independent evolution.  相似文献   


19.
20.
Background: Climate warming has been causing an increase in tall shrub cover around the Arctic, however, mammalian herbivory has been shown to inhibit shrub expansion. Though the effect of reindeer (Rangifer tarandus) and many other mammals has been widely studied in this context, the role of the mountain hare (Lepus timidus) in subarctic Scandinavia remains unknown.

Aims: To quantify browsing from mountain hare and reindeer on tall shrubs in different vegetation types and to investigate differences in shrub preference between the two.

Methods: In the summers of 2013 and 2014, we counted signs of browsing by hare and reindeer on tall shrub species in 31 study plots at three alpine locations in the Scandes range, Sweden.

Results: Hare browsing was significantly more frequent than that by reindeer in two (dry-mesic heath and dry meadow) out of seven vegetation types studied. Reindeer browsing was significantly higher in the low herb meadow and Långfjället shrub heath. Two shrub species, Betula nana and Salix hastata, were significantly more browsed by hare, while reindeer browsing was significantly higher on S. phylicifolia and S. lapponum.

Conclusions: Our results show that mountain hares can cause extensive damage to tall shrubs in the subarctic and may have a stronger impact on shrub communities than previously recognised.  相似文献   


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