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912. A new species of the rare endoparasitic copepod Entobius (Copepoda: Entobiidae) from Mexico with a key to the species of the genus
- Creator:
- Suárez-Morales, Eduardo and Carrera-Parra, Luis F.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- symbiotic copepods, parasitic crustaceans, invertebrate taxonomy, benthic polychaetes, and endoparasites
- Language:
- English
- Description:
- In a study of the benthic polychaete fauna of the southern Gulf of Mexico and the Caribbean Sea, several specimens of the terebellid polychaete Scionides reticulata (Ehlers) were found to host endoparasitic copepods that represent an undescribed species of the rare cyclopoid genus Entobius Dogiel, 1948. The new species, E. scionides sp. n., can be distinguished from its congeners by a combination of characters including a genital region without constrictions, three-segmented antennules, a reduced antenna with a blunt terminal process, reduced ornamentation of endopods of legs 1-4 and its relatively small size (2.3-2.7 mm). It is the smallest species of the genus. Comments on immature females are also provided, but males of this species remain unknown. It has a high prevalence (53%) in populations of the terebellid S. reticulata in the southern Gulf of Mexico, but it is absent from the Caribbean. This is the first occurrence of this copepod genus in the Americas. The finding of the new species of Entobius in S. reticulata confirms the strict specificity of most members of the genus and expands the host range of this copepod genus. A key for the identification of the species of Entobius is provided.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
913. A new species, Gnathia nkulu sp. n. (Crustacea: Isopoda: Gnathiidae) from southern Africa
- Creator:
- Smit, Nico J. and Van As, Jo G.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Gnathia nkulu, description, taxonomy, and morphology
- Language:
- English
- Description:
- A new species, Gnathia nkulu sp. n. is described from material collected off the South African coast at 80-200m depth. It differs from the intertidal species Gnathia africana Barnard, 1914 in that the mediofrontal process is not deeply divided into two lobes, article 2 of the pylopod is rounded and small wart-like tubercles and long simple setae are present on both the cephalosome and pereon.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
914. A new suite of twenty-two polymorphic microsatellite loci in the parasitic wasp, Habrobracon hebetor (Hymenoptera: Braconidae): Promising molecular tools for studying the population genetics of several beneficial braconid species
- Creator:
- Gerba, Madougou, Loiseau, Anne, Benoit, Laure, and Gauthier, Nathalie
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, blanokřídlí, lumčíkovití, populační genetika, Hymenoptera, Braconidae, population genetics, Habrobracon hebetor, Bracon spp., biological control, parasitic wasp, microsatellite, gene flow, 2, and 59
- Language:
- English
- Description:
- Combining a biotin-enrichment protocol and 454GS-FLX titanium pyrosequencing technology, we characterised 22 polymorphic microsatellite loci from the parasitic wasp, Habrobracon hebetor (Say) (Hymenoptera: Braconidae), a cosmopolitan species commonly used in biological control against a wide range of both major lepidopterous pests of stored products and field crops in different parts of the world. Three multiplex PCR sets were optimised and characterised across 46 H. hebetor specimens from two samples collected from millet fields in Niger. Two to 11 alleles were found per locus and observed heterozygosity ranged from 0.289 to 0.826. Polymorphism was detected in both samples with a similar level of observed heterozygosity (0.482 vs. 0.502) and number of alleles (4.1 vs. 3.6). Deviation from Hardy-Weinberg equilibrium was detected at the same five loci in both samples and five or seven more loci in each sample but was not associated with heterozygote deficiencies. Even though evidence for linkage disequilibrium was found between a few alleles, these new loci segregated independently. The variability of the 22 loci will enable estimates of genetic diversity and structure patterns, as well as gene flow between H. hebetor populations at different spatial scales. Cross-species amplifications were successful among the six Bracon spp. tested and nine loci will be particularly appropriate for population genetic studies in B. brevicornis., Madougou Garba, Anne Loiseau, Laure Benoit, Nathalie Gauthier., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
915. A new trematode species Neoplagioporus kajika sp. n. (Digenea: Opecoelidae), parasitic in the Japanese fluvial sculpin, Cottus pollux (Osteichthyes: Scorpaeniformes: Cottidae), from Japan
- Creator:
- Urabe, Misako and Higa, Eriko
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Digenea, Neoplagioporus kajika, adult, freshwater sculpin, Cottus pollux, and Japan
- Language:
- English
- Description:
- The adult morphology is described and illustrated of Neoplagioporus kajika sp. n. (Digenea: Opecoelidae) found in the Japanese fluvial sculpin Cottus pollux Günther (Osteichthyes: Scorpaeniformes: Cottidae) collected in the Naka River at Terase Bridge, Narutake, Nakagawa Town, Fukuoka Prefecture, Kyushu, Japan. This new species is characterized by that the body shape is oval, that the intestinal caeca end posteriorly at the middle level of the testicular region, that the ovary is trilobed, and that the vitelline follicles are distributed between the pharyngeal level and usually the posterior end of body and fill up the lateral fields of body. The new species is different from three hitherto known Neoplagioporus species, N. zacconis (Yamaguti, 1934) Shimazu, 1990 (type species), N. ayu (Takahashi, 1928) Shimazu, 1990, and N. elongatus (Goto et Ozaki, 1930) Shimazu, 1990, in a combination of these characteristics. The new species is considered mainly infective to C. pollux in the river.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
916. A new viewpoint to understand the response of leaf dark respiration to elevated CO2 concentration
- Creator:
- Qiao, Y.-Z., Zhang, Y.-B., Wang, K.-Y., Wang, Y.-P., Xu, Y., and Li, Q.-C.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- controlled environment chambers, Fargesia denudata, net photosynthetic rate, Populus cathayanna, and species differences
- Language:
- Multiple languages
- Description:
- By investigating the RD-Ca (dark respiration rate-atmospheric CO2 concentration) and PN (net photosynthetic rate)-Ca curves of bamboo (Fargesia denudata) and poplar (Populus cathayanna), we found that: (1) the minimal RD was close to ambient CO2 concentration, and the elevated or decreased atmospheric CO2 concentration enhanced the RD of both species; (2) the response curves of RD-Ca were simulated well by quadratic function. This phenomenon might be an inherent property of leaf R of F. denudata and P. cathayanna. If this was true, it implies that effect of CO2 on RD could be interpreted with the relationship of RD-Ca curves and the quadratic function. and Y.-Z. Qiao ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
917. A newly developed SGB buffer greatly enhances energy transfer efficiency from phycobilisomes to photosystem II in cyanobacteria in vitro
- Creator:
- Chen, L. P., Wang, Q. X., and Ma, W. M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, energy transfer efficiency, photosystem II, phycobilisome, SGB buffer, Synechocystis sp. PCC 6803, thylakoid membrane, 2, and 58
- Language:
- Multiple languages
- Description:
- The transfer of light energy from phycobilisomes (PBS) to photosystem II (PSII) reaction centers is vital for photosynthesis in cyanobacteria and red algae. To investigate the relationship between PBS and PSII and to optimize the energy transfer efficiency from PBS to PSII, isolation of the PBS-PSII supercomplex is necessary. SPC (sucrose/phosphate/citrate) is a conventional buffer for isolating PBS-PSII supercomplex in cyanobacteria. However, the energy transfer occurring in the supercomplex is poor. Here, we developed a new buffer named SGB by adding 1M glycinebetaine and additional sucrose to SPC buffer. Compared to SPC, the newly developed SGB buffer greatly enhanced the associated populations of PBS with thylakoid membranes and PSII and further improved the energy transfer efficiency from PBS to PSII reaction centers in cyanobacteria in vitro. Therefore, we conclude that SGB is an excellent buffer for isolating the PBS-PSII supercomplex and for enhancing the energy transfer efficiency from PBS to PSII reaction centers in cyanobacteria in vitro., L. P. Chen, Q. X. Wang, W. M. Ma., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
918. A non-invasive method for detecting the metabolic stress response in rodents: characterization and disruption of the circadian corticosterone rhythm
- Creator:
- Thanos, P. K., Cavigelli, S. A., Michaelides, M., Olvet, D. M., Patel, U., Diep, M. N., and Volkow, N. D.
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, fyziologie, stres (fyziologie), metabolity, cirkadiánní rytmy, physiology, stress (physiology), metabolites, circadian rhythms, corticosterone, fecal steroid metabolites, 2, and 577
- Language:
- English
- Description:
- Plasma corticosterone (CORT) measures are a common procedure to detect stress responses in rodents. However, the procedure is invasive and can influence CORT levels, making it less than ideal for monitoring CORT circadian rhythms. In the current paper, we examined the applicability of a non-invasive fecal CORT metabolite measure to assess the circadian rhythm. We compared fecal CORT metabolite levels to circulating CORT levels, and analyzed change in the fecal circadian rhythm following an acute stressor (i.e. blood sampling by tail veil catheter). Fecal and blood samples were collected from male adolescent rats and analyzed for CORT metabolites and circulating CORT respectively. Fecal samples were collected hourly for 24 h before and after blood draw. On average, peak fecal CORT metabolite values occurred 7-9 h after the plasma CORT peak and time-matched fecal CORT values were well correlated with plasma CORT. As a result of the rapid blood draw, fecal production and CORT levels were altered the next day. These results indicate fecal CORT metabolite measures can be used to assess conditions that disrupt the circadian CORT rhythm, and provide a method to measure long-term changes in CORT production. This can benefit research that requires long-term glucocorticoid assessment (e.g. stress mechanisms underlying health)., P. K. Thanos ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
919. A non-linear rainfall-runoff model with a sigmoid gain factor to simulate flow frequency distribution curves for Amazon catchments
- Creator:
- Vinagre, Marco Valério A., Blanco, Claudio J. C., and Amarante Mesquita, André L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- hydrological modeling, flow frequency distribution curves, Amazon small catchments, hydrologické modelovanie, čiara rozdelenia prietokov, and malé povodia riekyAmazonka
- Language:
- Slovak
- Description:
- The objective of this paper is to simulate flow frequency distribution curves for Amazon catchments with the aim of scaling power generation from small hydroelectric power plants. Thus, a simple nonlinear rainfall-runoff model was developed with sigmoid-variable gain factor due to the moisture status of the catchment, which depends on infiltration, and is considered a factor responsible for the nonlinearity of the rainfall-runoff process. Data for a catchment in the Amazon was used to calibrate and validate the model. The performance criteria adopted were the Nash-Sutcliffe coefficient (R²), the RMS, the Q95% frequency flow percentage error, and the mean percentage errors ranging from Q5% to Q95%.. Calibration and validation showed that the model satisfactorily simulates the flow frequency distribution curves. In order to find the shortest period of rainfall-runoff data, which is required for applying the model, a sensitivity analysis was performed whereby rainfall and runoff data was successively reduced by 1 year until a 1.5-year model application minimum period was found. This corresponds to one hydrological year plus the 6-month long ''memory''. This analysis evaluates field work in the ungauged sites of the region. and Cieľom tohto príspevku je simulácia čiar rozdelenia prietokov pre povodia rieky Amazonka pre potreby hodnotenia premeny energie v malých hydroelektrárňach. Preto bol vyvinutý jednoduchý nelineárny zrážko-odtokový model so sigmoidálne sa meniacim zdrojovým faktorom v závislosti od obsahu vody v povodí, ktorý závisí od infiltrácie a je považovaný za faktor, spôsobujúci nelinearitu zrážkoodtokových procesov. Pre kalibráciu a validizáciu modelu boli použité údaje z povodí rieky Amazonka. Použili sme tieto hodnotiace kritériá: Nashov-Sutcliffov koeficient (R²), RMS, Q95%, chyba určenia odtoku v percentách, a priemerná percentuálna chyba v rozsahu od Q5% do Q95%. Kalibrácia a validizácia ukázala, že model simuluje čiary rozdelenia prietokov uspokojivo. Aby bolo možné nájsť najkratšie obdobie pre nájdenia závislosti zrážky - odtok, ktorá je potrebná pre aplikáciu v modeli, použili sme citlivostnú analýzu tak, že údaje zrážky - odtok boli postupne redukované o jeden rok, až kým nebolo nájdené minimálne obdobie pre aplikáciu vzťahu zrážky - odtok 1,5 roka. Toto obdobie zodpovedá jednému hydrologickému roku, plus 6 mesiacov dlhá ''pamäť''. Touto analýzou boli vyhodnotené výsledky terénnych meraní v oblastiach, kde neboli k dispozícii merania odtoku.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
920. A note on integral vortex strength
- Creator:
- Kolář, Václav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- circulation, unsteady Taylor vortex, vortex intensity, vortex strength, vorticity, vorticity decomposition, cirkulace, nestacionární Taylorův vír, intenzita víru, síla víru, vířivost, and rozklad vířivosti
- Language:
- Slovak
- Description:
- Controversial aspects of the conventional and widely used concept of the integral vortex strength are briefly discussed. The strength of a vortex is usually calculated as the circulation along the vortex boundary, or equivalently due to Green’s theorem, as the surface integral of vorticity over the planar vortex cross section. However, the local effect of an arbitrary ''superimposed shear'' is fully absorbed by vorticity what makes the circulation a shear-biased vortex characteristic. The present paper shows that different vortexstrength models can be derived on the basis of different local vortex intensities proposed in the literature. The outcome of these models naturally differs, even for an ideally axisymmetric vortex. Three different vortex-strength models are compared and discussed by examining the unsteady Taylor vortex. and V práci jsou stručně diskutovány sporné stránky konvenčního a široce užívaného pojetí integrální síly víru. Síla víru je obvykle počítána jako cirkulace podél hranice víru nebo ekvivalentně podle Greenovy věty jako plošný integrál vířivosti přes příčný rovinný řez vírem. Lokální efekt libovolného ''superponovaného smyku'' je však plně absorbován vířivostí, což činí z cirkulace smykově zkreslenou vírovou charakteristiku. Tento článek ukazuje, že lze odvodit různé modely síly víru na základě různých lokálních intenzit víru navržených v odborné literatuře. Výsledky těchto modelů se přirozeně liší, dokonce i pro ideálně osově symetrický vír. Na podkladě zkoumání nestacionárního Taylorova víru jsou porovnány a diskutovány tři různé modely síly víru.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public