1,558 research outputs found
Fish Assemblage of Cedar Fork Creek, Ohio, Unchanged for 28 Years
Author Institution: Dept of Evolution, Ecology & Organismal Biology, The Ohio State University, Mansfield, OHAuthor Institution: Museum of Comparative Zoology, Dept of Ichthyology, Harvard University, Cambridge, MAA 270 m section of Cedar Fork Creek, a clear, gravel-bottomed, headwater stream of the Ohio River System in north-central Ohio, was sampled 48 times from 1975-2003. During the 28 year period 32,237
individuals of 10 fish families and 44 species were collected. Eight taxa made up 86% of the total number collected. Cyprinids (Luxilus cornutus, Campostoma anomalum, Pimephales notatus, Semotilus atromaculatus,
and Notropis buccatus) accounted for 65% of the individuals. Two darter species Etheostoma caeruleum, E. nigrum) made up 17.4% of the total, and the white sucker, Catostomus commersoni, accounted for 3.3%. The same common species were abundant throughout the 28 years, and the same rare species were consistently present in small numbers. Species richness averaged 23 species per year. Margalef’s index of diversity varied only slightly from 2.8 to 3.6 during the study indicating the constancy
of species composition. Two jackknife estimators (nonparametric resampling procedures) suggested that the collections detected 97-100% of the species present. Exotic species failed to make inroads into the Cedar Fork community except for carp, Cyprinus carpio, that have been in Ohio since 1879, and brown trout, Salmo trutta, that were recently stocked by the Ohio Department of Natural Resources
Ecological Analysis of the Fish Distribution in Green Creek, A Spring-Fed Stream in Northern Ohio
Author Institution: Department of Zoology, The Ohio State UniversityThe distribution of fishes in Green Creek, a spring-fed tributary of Sandusky Bay in northern Ohio, was studied from June 1976 through June 1977. A total of 31 species representing 22 genera and 10 families was taken at 8 stations along the length of the creek. Two cold water springs interrupt the longitudinal succession of fishes and cause the stream to be divided into 4 divisions, each with its own ecological characteristics and fauna: I. Upland warm water tributaries with Catostomous commersoni and cyprinids dominant. II. Cold water trout stream produced by stocking Salmo gairdneri near the spring; Coitus bairdi is an abundant native species in this division. III. Marl substrate of low gradient with Catostomous commersoni, cyprinids, darters, and Coitus bairdi. IV. Estuary of Lake Erie with typical lake fishes. The stations with the highest macroinvertebrate biomass also had the highest fish biomass. Various physical and chemical measurements were made, and it was determined that the marl deposits of the springs were not conducive to fish productivity. The distribution of fishes in Green Creek does not follow the classical pattern of longitudinal zonation but is determined by the unusual physical and chemical parameters induced by the springs
Incidence of Black Spot Disease in Fishes in Cedar Fork Creek, Ohio
Author Institution: Department of Zoology, The Ohio State University, Mansfield CampusA total of 4175 fishes belonging to 29 taxa in 6 families was examined for black spot disease. Of that total, 89% were infected with one or more metacercariae of the strigeid fluke, Uvulifer ambloplitis. Rhinichthys atratulus, Semotilus atromaculatus and Campostoma anomalum had the highest incidence of infection and the greatest number of individual parasites. Other pool-dwelling minnows such as Notropis cornutus and Pimephales notatus were also heavily infected, whereas Noiropis photogenus, which prefers deep, swift riffles, had very few cysts. The only non-minnows to approach the high totals of the pool-dwelling cyprinids were Catostomus commersoni and Etheostoma nigrum. Hypentelium nigricanz, which prefers faster water than Catostomus and three species of Etheostoma, which, unlike E. nigrum, are rime dwelling forms, also had lower incidences of infection and fewer cysts. Coitus bairdi, another rapid water species, did not develop black spot disease. Only 1 specimen of 225 Ericymba buccata, which occur over shifting, sandy bottoms, had a single cyst. Our data suggest that the species which inhabit the slower flowing waters of a stream are likely to be more heavily infected than their relatives which prefer faster water because snail hosts are absent and any cercariae present are more likely to be swept away in rapid water and thus have less of a chance to penetrate a host
U–Pb zircon geochronology of volcanic deposits from the Permian basin of the Orobic Alps (Southern Alps, Lombardy): chronostratigraphic and geological implications
U\u2013Pb zircon ages from volcanic rocks of Early Permian age (Southern Alps, Lombardy), associated with fault-controlled transtensional continental basins, were determined with the laser ablation (LA)-ICP-MS technique. Four samples were collected at the base and at the top of the up to 1000 m thick volcaniclastic unit of the Cabianca Volcanite. This unit pre-dates the development of a sedimentary succession that still contains, at different stratigraphic levels, volcanic intercalations. Age results from a tuff in the basal part of the unit constrain the onset of the volcanic activity to 280 \ub1 2.5 Ma. Ignimbritic samples from the upper part of the unit show a large scatter in the age distribution. This is interpreted as the occurrence of antecrystic and autocrystic zircons. The youngest autocrystic zircons (c. 270 Ma) are thus interpreted as better constraining the eruption age, constraining the duration of the volcanic activity in the Orobic Basin to about 10 Ma. The new geochronological results compared with those of other Early Permian basins of the Southern Alps reveal important differences that may reflect (1) a real time-transgressive beginning and end of the volcanic activity or (2) the complex mixing of antecrystic and autocrystic zircon populations in the analysed samples
Large-scale progradation, demise and rebirth of a high-relief carbonate platform (Triassic, Lombardy Southern Alps, Italy)
The Upper Anisian to Early Carnian succession of the Middle Val Brembana-Pegherolo Massif (Central Southern Alps of Italy) records a complete depositional cycle from platform inception to growth, demise and rebirth. The depositional architecture of this system reflects different evolutionary stages: an inception stage which postdates a previous drowning of an Anisian carbonate platform with progradation of the carbonate platform from the nucleation areas, an aggradational stage with increasing water depth in the basins, a progradational stage where steep slopes composed of margin-derived breccias develop and a final crisis corresponding to the subaerial exposure of the platform top, followed by the deposition of shales in the basin before the rebirth of a different type of carbonate factory. The record of this evolution reflects the effects of the change in accommodation space (interplay of subsidence and eustacy), which controls the type and storage sites of the sediments produced by the carbonate factory. The effects of the changes in accommodation space are recorded in the shallow water platform as well as in the intraplatform basins, where the sediments, delivered at different rates from the platform top are stored. As a consequence, the aggradational stage corresponds to reduced sedimentation in the basins (i.e. sediments are stored on the platform top) whereas during progradation resedimented limestones are more common in the basin. Subaerial exposure rapidly halted the carbonate production on the platform top, while a major input of shales (probably reflecting a climate change and/or lowering of the base level) is recorded in the basin, where shales onlap the slope of the previous carbonate system. The rebirth of the carbonate factory after subaerial exposure of the platform top is characterized by a different composition of the carbonate factory, probably reflecting changes of the environmental conditions. The step-by-step recording of the evolution of the carbonate system represents a unique opportunity to record a seismic-scale complete evolutionary cycle of a carbonate system in its different sub-environments, from the platform top to the basin
Reindentification of William Bartram\u27s Savannah River \u3cem\u3eAmbloplites\u3c/em\u3e, with Early Evidence for a Tennessee-Savannah Faunal Exchange
Risk genes in head and neck cancer: a systematic review and meta-analysis of last 5 years
Head and Neck Carcinoma (HNC), of which the majority are squamous cell carcinomas of the head and neck (SCCHN), is the sixth most prevalent cancers in mankind and, presents high morbidity and low rates of survival.1 It is known that the apoptotic and proliferation genes are involved in cancer development and these could be useful as a biomarker of this pathology. Systematic reviews and meta-analysis allow stronger and more generalized conclusions for identifying some models of risk markers. These models may help in screening, early diagnosis and/or therapy in the clinic.2-5 In recent decades, there has been increased interest in genetic predisposition studies in complex disease. This has led to the production of an enormous number of epidemiologic papers about the relationship between genetic polymorphism and disease. However, the magnitude of association between specific polymorphism and disease is still not established. The identification of a predictive model of risk polymorphisms could help in early diagnosis, and in understanding disease recurrence and/or progression in the subset of patientssubmittedVersio
Transition between terrestrial-submerged walking and swimming revealed by Early Permian amphibian trackways and a new proposal for the nomenclature of compound trace fossils
Exceptionally preserved Early Permian tetrapod trackways from the Orobic Basin (Central-Western Southern Alps) offer a unique opportunity to investigate in detail locomotion in fossil vertebrates that lived on continental European landmasses. Herein are reported the results of a study on several tetrapod trackways that display a large variety of behavioral, gait and substrate related extramorphologies. They clearly document the transition from terrestrial-underwater walking to swimming and are assigned to the compound ichnotaxon Batrachichnus C Lunichnium. The use of the "C" symbol is here introduced for the first time as nomenclatural indication of a Compound trace. Producers were probably small-sized temnospondyl or lepospondyl (microsaurs) amphibians. Comparisons with living urodelan anatomy and mechanics provide evidence for conservatism of locomotor mechanics in evolutionary history among amphibians. The derived model for locomotor kinematics in Early Permian amphibians provides a reference for interpreting transitional land-to-water trackways. The shift from walking to swimming behavior in early tetrapods, as in extant urodelan amphibians, is described as a complex balance between different dynamics
The central role of endothelium in hereditary angioedema due to C1 inhibitor deficiency
An impairment of the endothelial barrier function underlies a wide spectrum of pathological conditions. Hereditary angioedema due to C1-inhibitor deficiency (C1-INH-HAE) can be considered the \u201cpathophysiological and clinical paradigm\u201d of Paroxysmal Permeability Diseases (PPDs), conditions characterized by recurrent transient primitively functional alteration of the endothelial sieving properties, not due to inflammatory-ischemic-degenerative injury and completely reversible after the acute flare. It is a rare yet probably still underdiagnosed disease which presents with localized, non-pitting swelling of the skin and submucosal tissues of the upper respiratory and gastrointestinal tracts, without significant wheals or pruritus. The present review addresses the pathophysiology of C1-INH-HAE with a focus on the crucial role of the endothelium during contact and kallikrein/kinin system (CAS and KKS) activation, currently available and emerging biomarkers, methods applied to get new insights into the mechanisms underlying the disease (2D, 3D and in vivo systems), new promising investigation techniques (autonomic nervous system analysis, capillaroscopy, flow-mediated dilation method, non-invasive finger plethysmography). Hints are given to the binding of C1-INH to endothelial cells. Finally, crucial issues as the local vs systemic nature of CAS/KKS activation, the episodic nature of attacks vs constant C1-INH deficiency, pros and cons as well as future perspectives of available methodologies are briefly discussed
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