scholarly journals Brook trout (Salvelinus fontinalis) response to wood removal from high-gradient streams of the Adirondack Mountains (N.Y., U.S.A.)

2003 ◽  
Vol 60 (4) ◽  
pp. 379-389 ◽  
Author(s):  
Dana R Warren ◽  
Clifford E Kraft
Keyword(s):  
Brook Trout ◽  
Salvelinus Fontinalis ◽  
Woody Debris ◽  
Second Order ◽  
Adirondack Mountains ◽  
Stream Order ◽  
Third Order ◽  
Order Stream ◽  
First Order ◽  
Linear Contrasts

A before–after, control–impact study was conducted to evaluate brook trout (Salvelinus fontinalis) response to the removal of debris dams and woody debris from an ice-storm-impacted stream system in the eastern Adirondack Mountains in New York State. A total of 10 reach pairs were established on two first-order streams, two second-order streams, and one third-order stream, all within the same watershed. Analyses, conducted separately for each stream order, used linear contrasts to compare differences in trout abundance between reference (upstream) and removal (downstream) reaches 1 month and 1 year after the manipulation. We expected trout abundance to decrease in removal reaches relative to reference reaches; however, responses varied temporally and with respect to stream order. Trout abundance had not changed significantly 1 month after removal. One year after removal, relative trout abundance had increased in the third-order stream, decreased in the second-order streams, and exhibited no significant change in the first-order streams. In areas with abundant boulders and preexisting habitat complexity, accumulated woody debris may have limited influence on trout abundance.

Evidence for general base catalysis by protic solvents in a kinetic study of alcoholyses and hydrolyses of 1-(phenoxycarbonyl)pyridinium ions under both solvolytic and non-solvolytic conditions

2009 ◽  
Vol 74 (1) ◽  
pp. 43-55 ◽  
Author(s):  
Dennis N. Kevill ◽  
Byoung-Chun Park ◽  
Jin Burm Kyong
Keyword(s):  
Second Order ◽  
Base Catalysis ◽  
Substitution Reactions ◽  
Third Order ◽  
Methoxy Derivative ◽  
First Order ◽  
General Base ◽  
Protic Solvents ◽  
Kinetics Of ◽  
Pyridinium Ions

The kinetics of nucleophilic substitution reactions of 1-(phenoxycarbonyl)pyridinium ions, prepared with the essentially non-nucleophilic/non-basic fluoroborate as the counterion, have been studied using up to 1.60 M methanol in acetonitrile as solvent and under solvolytic conditions in 2,2,2-trifluoroethan-1-ol (TFE) and its mixtures with water. Under the non- solvolytic conditions, the parent and three pyridine-ring-substituted derivatives were studied. Both second-order (first-order in methanol) and third-order (second-order in methanol) kinetic contributions were observed. In the solvolysis studies, since solvent ionizing power values were almost constant over the range of aqueous TFE studied, a Grunwald–Winstein equation treatment of the specific rates of solvolysis for the parent and the 4-methoxy derivative could be carried out in terms of variations in solvent nucleophilicity, and an appreciable sensitivity to changes in solvent nucleophilicity was found.

Panicle, spikelet, and floret development in orchardgrass (Dactylis glomerata)

1993 ◽  
Vol 71 (4) ◽  
pp. 523-532 ◽  
Author(s):  
Joanna Fraser ◽  
Eric G. Kokko
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Unique Feature ◽  
Dactylis Glomerata ◽  
Bilateral Symmetry ◽  
Second Order ◽  
Third Order ◽  
First Order ◽  
Lateral Branches ◽  
Scanning Electron

The initial stages of panicle, spikelet, and floret development in field-grown 'Kay' orchardgrass were examined using scanning electron microscopy. Spikelets arose from a complex multilevelled sequence of initiation from branch apices. Spikelets developed indirectly in a two-tiered progression: (i) an acropetal and basipetal sequence of first order, second-order, and third-order inflorescence apices, and (ii) an acropetal development within subclusters of higher-order lateral branch inflorescence apices. The panicle had the unique feature of dorsiventrality as well as bilateral symmetry. The basal apex from first-order, second-order, or third-order apices developed on the same side of the main axis as the first-order apex. The two glumes subtending each spikelet primordium developed alternately and acropetally. Development and initiation of florets within spikelets was basipetal within the panicle, basipetal within clusters and subclusters of spikelets on lateral branches, and acropetal within spikelets. Within florets, paleas developed later than lemmas. Key words: Dactylis glomerata, cocksfoot, scanning electron microscopy, development, panicle.

Performance of Indigenous, Exotic, and Hybrid Strains of Brook Trout (Salvelinus fontinalis) in Waters of the Adirondack Mountains, New York

1981 ◽  
Vol 38 (12) ◽  
pp. 1701-1707 ◽  
Author(s):  
Dwight A. Webster ◽  
William A. Flick
Keyword(s):  
New York ◽  
Brook Trout ◽  
Salvelinus Fontinalis ◽  
Hybrid Vigor ◽  
Superior Performance ◽  
Adirondack Mountains ◽  
Wild Strains ◽  
Early Fall ◽  
Survival And Growth ◽  
Wild Trout

Eleven year-classes of wild, domestic, and wild × domestic hybrid strains of brook trout (Salvelinus fontinalis) were stocked in a 0.19-ha Adirondack pond. Comparative survival and growth were assessed upon drainage in early fall. Rearing native wild strains to maturity in a hatchery, or domestic strains in a natural environment, did not consistently or materially affect survival of progeny, suggesting that superior performance of wild strains was largely inherent. Interstrain hybrids of wild × domestic showed survivals equivalent to the wild parents, but hybrids of two Canadian strains gave evidence of heterosis in both survival and net yield. Supplementary observations in other waters also indicated that one strain (Assinica) may be less adaptable to Adirondack conditions than the other (Temiscamie).Key words: brook trout, wild trout, domesticated trout, interstrain hybrid trout, survival, growth, heterosis, hybrid vigor

Long-Term Effects of Large Woody Debris Addition on Stream Habitat and Brook Trout Populations

2010 ◽  
Vol 1 (2) ◽  
pp. 146-151 ◽  
Author(s):  
John A. Sweka ◽  
Kyle J. Hartman ◽  
Jonathan M. Niles
Keyword(s):  
Brook Trout ◽  
Habitat Complexity ◽  
Salvelinus Fontinalis ◽  
Woody Debris ◽  
Large Woody Debris ◽  
Stream Habitat ◽  
Long Term Effects ◽  
Habitat Manipulation ◽  
Central Appalachians

Abstract In this study, we resurveyed stream habitat and sampled brook trout Salvelinus fontinalis populations 6 y after large woody debris additions to determine long-term changes in habitat and brook trout populations. In a previous study, we added large woody debris to eight streams in the central Appalachians of West Virginia to determine whether stream habitat could be enhanced and brook trout populations increased following habitat manipulation. The large woody debris additions had no overall effect on stream habitat and brook trout populations by 6 y after the additions. The assumption that a lack of large woody debris is limiting stream habitat and brook trout populations was not supported by our results. In high-gradient streams, habitat complexity may be governed more by the abundance of boulders and large woody debris may have a lesser influence on trout populations.

A Note on Homogeneous Dendrites

1968 ◽  
Vol 11 (1) ◽  
pp. 85-93 ◽  
Author(s):  
Z. A. Melzak
Keyword(s):  
Branch Point ◽  
Rooted Tree ◽  
Second Order ◽  
Third Order ◽  
First Order ◽  
Graph Theoretic ◽  
Order Branch

In graph - theoretic terms a homogeneous p-dendrite, p ≥ 2, is defined as a finite singly-rooted tree in which the root has valency 1 while every other vertex has valency 1 or p. More descriptively, a homogeneous p-dendrite may be imagined to start from its root as the main, or 0th order, branch which proceeds to the first - order branch point where it gives rise top first - order branches. Each of these either terminates at its other end (which is a second-order branch point) or it splits there again into p branches (which are of third order), and so on. The order of the dendrite is the highest order of a branch present in it. For completeness, a 0-th order dendrite is also allowed, this consists of the 0-th order branch alone.

Structure and composition of unmanaged riparian forests in the coastal mountains of Oregon, U.S.A.

1999 ◽  
Vol 29 (10) ◽  
pp. 1557-1573 ◽  
Author(s):  
Robert J Pabst ◽  
Thomas A Spies
Keyword(s):  
Spatial Scales ◽  
Canopy Cover ◽  
Basal Area ◽  
Tree Regeneration ◽  
Riparian Forests ◽  
Stream Order ◽  
Third Order ◽  
First Order ◽  
Hardwood Tree ◽  
Stand Attributes

We characterized the structure and composition of unmanaged riparian forests in three river basins in Oregon's coastal mountains. Our objective was to evaluate stand attributes at three spatial scales: streamside (site), drainage network (stream order), and basin (subregion). Data on basal area, species composition, snag density, canopy cover, and tree regeneration were collected along transects at 124 sites. Conifer basal area increased with distance from stream, a trend similar among subregions, and was highest at sites along first-order streams. Hardwood basal area was relatively constant with distance from stream and was proportionally higher at sites along second- and third-order streams than at sites along first-order streams. Conifer and hardwood tree regeneration occurred infrequently and varied by topographic position, stream order, and subregion. Conifer regeneration was associated with basal area of shade-tolerant conifers and appeared to be limited by shrub competition. The unmanaged forests we studied were characterized by a patchy mosaic of structure and composition. Hardwoods and shrubs were major components of the near-stream environment in these forests, whereas dominance of conifers was limited to hillslopes. It appears that fine-scale patterns associated with proximity to the stream are influenced by coarser scale factors such as valley-floor width and climate.

Differences in EDNO contribution to arteriolar diameters at rest and during functional dilation in striated muscle

1993 ◽  
Vol 265 (1) ◽  
pp. H146-H151 ◽  
Author(s):  
R. L. Hester ◽  
A. Eraslan ◽  
Y. Saito
Keyword(s):  
Striated Muscle ◽  
Physiological Role ◽  
Second Order ◽  
Muscle Stimulation ◽  
Third Order ◽  
First Order ◽  
Before And After ◽  
Arteriolar Vasodilation ◽  
Arteriolar Diameter

This study was designed to determine the physiological role of endothelium-dependent nitric oxide (EDNO) in the control of arteriolar diameter during rest and muscle stimulation. Diameters of first-, second-, and third-order arterioles in the superfused hamster cremaster muscle were measured before and throughout 1 min of field stimulation before and after inhibition of EDNO release. ENDO inhibition by intravenous N omega-nitro-L-arginine methyl ester (L-NAME) significantly attenuated the arteriolar vasodilation in response to 1 microM acetylcholine. First-order arterioles averaged 65 +/- 5 microns at rest and dilated to 86 +/- 6 microns during muscle stimulation (n = 9), second-order arterioles averaged 45 +/- 6 microns and dilated to 72 +/- 3 microns during muscle stimulation (n = 6), with third-order arterioles averaging 29 +/- 2 microns, and dilating to 53 +/- 3 microns during muscle stimulation (n = 7). EDNO inhibition significantly decreased both the resting diameter of first-order arterioles (57 +/- 4 microns) and functional dilation (68 +/- 3 microns; P <0.05). EDNO inhibition had no effect on the resting diameter of second-order arterioles (45 +/- 5 microns) yet significantly attenuated the functional dilation (64 +/- 4 microns; P < 0.05). EDNO inhibition had no effect on either the resting diameter of third-order arterioles (30 +/- 2 microns) or the functional dilation (49 +/- 2 microns).(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Clustering for semantic purposes

Terminology ◽  
2014 ◽  
Vol 20 (2) ◽  
pp. 279-303 ◽  
Author(s):  
Ann Bertels ◽  
Dirk Speelman
Keyword(s):  
Semantic Analysis ◽  
Second Order ◽  
Scaling Analysis ◽  
Distributional Semantics ◽  
Semantic Heterogeneity ◽  
Multidimensional Scaling Analysis ◽  
Third Order ◽  
Clustering Techniques ◽  
First Order ◽  
Fine Grained

This paper presents an innovative approach, within the framework of distributional semantics, for the exploration of semantic similarity in a technical corpus. In complement to a previous quantitative semantic analysis conducted in the same domain of machining terminology, this paper sets out to discover fine-grained semantic distinctions in an attempt to explore the semantic heterogeneity of a number of technical items. Multidimensional scaling analysis (MDS) was carried out in order to cluster first-order co-occurrences of a technical node with respect to shared second-order and third-order co-occurrences. By taking into account the association values between relevant first and second-order co-occurrences, semantic similarities and dissimilarities between first-order co-occurrences could be determined, as well as proximities and distances on a graph. In our discussion of the methodology and results of statistical clustering techniques for semantic purposes, we pay special attention to the linguistic and terminological interpretation.

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