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92. A new species of Nothobomolochus (Copepoda: Bomolochidae) parasitic on Engraulis anchoita (Pisces: Engraulidae) from Argentina
- Creator:
- Timi, Juan Tomás and Sardella, Norma Haydée
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Nothobomolochus cresseyi sp. п., parasitic Copepoda, and Engraulis anchoita
- Language:
- English
- Description:
- Nothobomolochus cresseyi sp. n. (Copepoda: Bomolochidae), a parasite from gills of the engraulid fish Engraulis anchoita Hubbs et Marini (Pisces: Engraulidae) from the coast of Argentina, is described and illustrated. The new species can be distinguished from other species of Nothobomolochus Vervoort, 1962 by the following combination of characters: three modified setae on the base of the antennule similar in length to the plumose setae, the nature of the armature of the third segment of the fourth endopod and the length and width of the thoracic somites 2 to 4 decreasing gradually. The new species represents the first record of this genus for Argentina.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
93. A new species of Paraberrapex Jensen, 2001 (Cestoda: Lecanicephalidea) from Squatina guggenheim Marini (Squatiniformes: Squatinidae) off Argentina
- Creator:
- Mutti, Leonardo D and Ivanov, Verónica A
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- tasemnice, tapeworms, Paraberrapex atlanticus sp. n., angel sharks, southwestern Atlantic Ocean, 2, and 59
- Language:
- English
- Description:
- Paraberrapex atlanticus sp. n. (Cestoda: Lecanicephalidea) is described from the spiral intestine of the angel shark Squatina guggenheim Marini from coastal waters off Buenos Aires Province, Argentina. Paraberrapex atlanticus sp. n. can be distinguished from the only species described in the genus, P. manifestus Jensen, 2001 in having cocoons 5-6 times longer with more eggs per cocoon, the extension of the uterine duct, the distribution of vitelline follicles, and the size and density of microtriches on the bothridial surfaces. The presence of P. atlanticus sp. n. in S. guggenheim confirms the specificity of Paraberrapex Jensen, 2001 for squatiniform sharks., Leonardo D. Mutti, Verónica A. Ivanov., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
94. A new species of Spirorchis MacCallum, 1918 (Digenea: Schistosomatoidea) and Spirorchis cf. scripta from chicken turtle, Deirochelys reticularia (Emydidae), with an emendation and molecular phylogeny of Spirorchis
- Creator:
- Roberts, Jackson R, Orélis-Ribeiro, Raphael, Halanych, Kenneth M, Arias, Cova R, and Bullard, Stephen A
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitologie, parasitology, taxonomy, Spirorchiidae, Spirhapalum, 28S phylogeny, Baracktrema, 2, and 59
- Language:
- English
- Description:
- Chicken turtles, Deirochelys reticularia (Latreille in Sonnini et Latreille) (Testudines: Emydidae) from Alabama, USA were infected by Spirorchis collinsi Roberts et Bullard sp. n. and Spirorchis cf. scripta. The new species is most easily differentiated from its congeners by the combination of having caeca that extend far beyond the genitalia, intercaecal genitalia positioned in the middle portion of the body, a testicular column that nearly abuts the caecal bifurcation, a cirrus sac positioned between the testes and ovary, a massive Mehlis' gland, an elongate, longitudinal metraterm that extends anteriad beyond the level of the ovary, a pre-ovarian genital pore, and a prominent, intercaecal Manter's organ. The specimens of S. cf. scripta differed from the holotype and published descriptions of Spirorchis scripta Stunkard, 1923 by several subtle morphological features, perhaps comprising intraspecific variation, but collectively warranted a detailed description herein. Based on examinations of the aforementioned specimens plus the holotype, paratypes and vouchers of morphologically-similar congeners, Spirorchis MacCallum, 1918 is emended to include the presence of oral sucker spines, a pharynx, lateral oesophageal diverticula ('plicate organ') and a median oesophageal diverticulum ('oeseophageal pouch'). Phylogenetic analysis of the nuclear large subunit rDNA (28S) recovered S. collinsi sister to Spirorchis picta Stunkard, 1923, > 99% similarity between S. cf. scripta and S. scripta, and a monophyletic Spirorchis MacCallum, 1918. No blood fluke infection has been reported previously from these drainages, Alabama, or this turtle species. This is the first new species of Spirorchis to be described from North America in 26 years., Jackson R. Roberts, Raphael Orélis-Ribeiro, Kenneth M. Halanych, Cova R. Arias, Stephen A. Bullard., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
95. 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
96. 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
97. 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
98. A note on infinite aS-groups
- Creator:
- Nikandish, Reza and Miraftab, Babak
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- matematika, mathematics, infinite aS-group, supplemented subgroup, nilpotent group, 13, and 51
- Language:
- English
- Description:
- Let G be a group. If every nontrivial subgroup of G has a proper supplement, then G is called an aS-group. We study some properties of aS-groups. For instance, it is shown that a nilpotent group G is an aS-group if and only if G is a subdirect product of cyclic groups of prime orders. We prove that if G is an aS-group which satisfies the descending chain condition on subgroups, then G is finite. Among other results, we characterize all abelian groups for which every nontrivial quotient group is an aS-group. Finally, it is shown that if G is an aS-group and |G| ≠ pq, p, where p and q are primes, then G has a triple factorization., Reza Nikandish, Babak Miraftab., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
99. A note on model structures on arbitrary Frobenius categories
- Creator:
- Li, Zhi-Wei
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- matematika, mathematics, Frobenius categorie, triangulated categories, model structure, 13, and 51
- Language:
- English
- Description:
- We show that there is a model structure in the sense of Quillen on an arbitrary Frobenius category F such that the homotopy category of this model structure is equivalent to the stable category F as triangulated categories. This seems to be well-accepted by experts but we were unable to find a complete proof for it in the literature. When F is a weakly idempotent complete (i.e., every split monomorphism is an inflation) Frobenius category, the model structure we constructed is an exact (closed) model structure in the sense of Gillespie (2011)., Zhi-Wei Li., and Seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
100. A note on representing dowling geometries by partitions
- Creator:
- Matúš, František and Ben-Efraim, Aner
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- kybernetika, cybernetics, matroid representations, partition representations, Dowling geometries, Frobenius groups, 23, and 007
- Language:
- English
- Description:
- We prove that a rank ≥3 Dowling geometry of a group H is partition representable if and only if H is a Frobenius complement. This implies that Dowling group geometries are secret-sharing if and only if they are multilinearly representable., František Matúš and Aner Ben-Efraim., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public