Microdistributions of filter-feeding caddisflies (Insecta: Trichoptera) in a regulated Rocky Mountain river

A year-round study was conducted in the Blue River, Colorado, U.S.A., to examine microdistributions of the filter-feeding caddisflies Arctopsyche grandis and Brachycentrus occidentalis along a regulated stream environmental gradient. There was a well-defined longitudinal species replacement, with A. grandis reaching maximum densities 2.3 km below the impoundment and declining downstream as B. occidentalis increased. Arctopsyche grandis was often the only caddisfly found near the dam. The two species co-occurred at two downstream sites, with A. grandis numerically dominant 5.2 km below the impoundment and B. occidentalis at the farthest downstream site (11 km). Near the dam, where densities of filter-feeders were highest, there were significant relationships between individual rock surface area and the number of larvae during most sampling periods. Contrary to our predictions of selection of current-exposed microhabitats, both species occurred primarily on the bottom and lower lateral sides of rocks at all sites. Clumped distribution patterns in the absence of spatial segregation by size class suggests common microhabitat preferenda for species and instars. This use of similar spaces indicates that competitive displacement may occur, partially explaining the longitudinal distribution patterns. At a macroscale the reservoir-induced environmental alterations clearly limit the distribution of organisms, especially at sites directly below the impoundment. As the stream regains its preimpoundment character farther downstream, factors at a microscale may play a more important role in producing the distinct longitudinal distribution patterns.

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Analysis of the Most Valued Organization to Work for in Spain, According to Nationality and Location

Technology Transfer and Entrepreneurship ◽

10.2174/2213809906666181214125420 ◽

2019 ◽

Vol 5 (2) ◽

pp. 83-99

Author(s):

Francisco Jesús Ferreiro Seoane ◽

Manuel Octavio Del Campo Villares

Keyword(s):

Work Environment ◽

Talent Management ◽

Point Of View ◽

Added Value ◽

Quantitative Character ◽

Autonomous Communities ◽

Professional Performance ◽

Significant Relationships ◽

Pearson Correlations ◽

Selection Of

Background: The objective of this article is to analyse if there are significant relationships between the most valuable companies operating in Spain regarding professional performance, according to nationality and location within their Autonomous Communities or any superior aggrupation. To do that, a sample of 100 companies has been selected. Methods: The methodology followed is based on the selection of the 100 highestvalued companies from the point of view of Human Resources’ policy for the period 2013-2016 and through the measurement of six factors: Talent Management, Retribution, Work environment, CSR, Training and Employees’ perception, and classified by nationality and location. The study was based on 12 hypotheses, using the Unifactorial Variance’s Analysis, Pearson correlations and regressions. One limitation could be the fact that this study refers to a particular period, focusing on Spain and the variables mentioned, based on questionnaires. The added value of this work lies on the newness as it has a quantitative character, and on the fact that most of the hypotheses do not comply. Results and Conclusion: This allows to deny certain beliefs that affirm that European and American companies operating in Spain are more attractive than the Spanish or the Mediterranean ones.

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A comparison of the Charolais, British Friesian and Hereford breeds as sires of crossbred singlesuckled calves for beef production

Animal Science ◽

10.1017/s0003356100017050 ◽

1973 ◽

Vol 17 (3) ◽

pp. 267-273 ◽

Cited By ~ 5

Author(s):

R. E. Haycock ◽

D. A. Stewart

Keyword(s):

Weight Gain ◽

Birth Weight ◽

Live Weight ◽

The Other ◽

Cattle Production ◽

Significant Relationships ◽

Grazing Period ◽

Beef Cattle Production ◽

Breed Crosses ◽

Selection Of

SUMMARYIn three successive years cows from an Aberdeen Angus cross Shorthorn herd were mated to pedigree Charolais, British Friesian and Hereford bulls. A comparison of the progeny of the three breeds of sire under controlled conditions was therefore possible using a random selection of dams for mating, and identical rearing of the calves. Results for live-weight gain of the suckled progeny were analysed and showed superiority of the Charolais breed over the other two when used in this form of beef cattle production.For birth weights and daily live-weight gains, particularly during the grazing period, the Charolais cross progeny showed superiority over the other two. There was a consistent although not always statistically significant tendency for these differences between the breed crosses to occur in the male calves only, the females showing little difference between breeds. The data also showed highly significant relationships between gestation period and birth weight, both within and between breed crosses.

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Creativity and innovation through LMX and personal initiative

Journal of Organizational Change Management ◽

10.1108/jocm-09-2016-0183 ◽

2018 ◽

Vol 31 (2) ◽

pp. 323-333 ◽

Cited By ~ 5

Author(s):

Ashkan Khalili

Keyword(s):

Leadership Style ◽

Content Type ◽

Personal Initiative ◽

Significant Relationships ◽

Member Exchange ◽

Creativity And Innovation ◽

Moderating Role ◽

Practical Implications ◽

Selection Of

Purpose The purpose of this paper is to determine empirically the influence of leader-member exchange (LMX) on employees’ creativity and innovation. In addition, this study investigated the moderating role of employees’ personal initiative on the associations. Design/methodology/approach Data were gathered from 1,221 employees working in organizations across various industries in Australia. Findings The findings of this study revealed positive and significant relationships between LMX and employees’ creativity and innovation. Also, the findings indicated employees’ personal initiative moderated the LMX-employees’ creativity and LMX-employees’ innovation relationships. Practical implications Organizations should invest in LMX training and in the selection of leaders with this leadership style if their aim is to nurture and intensify employees’ creativity and innovation. They also should invest in personal initiative training in order to amplify the effect of LMX on creativity and innovation in organization. Originality/value This study makes vital theoretical contributions in different ways. In the domain of creativity and innovation, it addresses factors that impact employees’ creativity and innovation. It expands knowledge about organizational resources that nurture and enhance the creativity and innovation of employees. For LMX, this study supplements existing research by examining employees’ creativity and innovation as outcomes. Also, identifying personal initiative as an amplifier of the LMX-employees’ creativity and innovation relationships extends research in that domain. This study is also a rare investigation of the Australian context.

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Distribution of Grass Species and Attributes of Grasses Near a Bore Drain in a Grazed Semi-arid Subtropical Grassland

Australian Journal of Botany ◽

10.1071/bt96071 ◽

1997 ◽

Vol 45 (5) ◽

pp. 919 ◽

Cited By ~ 5

Author(s):

R. W. Rogers ◽

C. Stride

Keyword(s):

Introduced Species ◽

Carbon Assimilation ◽

Distribution Patterns ◽

Common Species ◽

Grass Species ◽

Semi Arid ◽

Selection Of

The distribution of grass species and a selection of attributes of those species were related to distance from water in an otherwise natural, sheep-grazed, semi-arid, subtropical grassland at Glencoban Station near Cunnamulla in south-western Queensland, Australia. Twenty common species could be classified as decreaser, increaser or neutral with respect to stocking pressure based on distribution patterns with respect to distance from water. No species known to be introduced to Australia were present. The occurrence of a diversity of vegetative and diaspore attributes and carbon assimilation pathways were also shown to be related to stocking pressure. The attributes studied showed autocorrelation in two groups, which related to the higher level taxonomy of the grasses and to response to stocking. Chloridoid grasses increase and andropogonoid grasses decrease under high stocking pressure. In this grassland, which has no introduced species, a syndrome of stocking-related attributes can be discerned.

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Biotic element analysis of reptiles of China: A test of vicariance model

Current Zoology ◽

10.1093/czoolo/59.4.449 ◽

2013 ◽

Vol 59 (4) ◽

pp. 449-457 ◽

Cited By ~ 5

Author(s):

Youhua Chen

Keyword(s):

East Asia ◽

Current Distribution ◽

Related Species ◽

Distribution Patterns ◽

Biodiversity Hotspots ◽

Element Analysis ◽

Closely Related Species ◽

Areas Of Endemism ◽

Guizhou Plateau ◽

Selection Of

Abstract In this contribution, I identify possible biotic elements of reptiles of China using biotic element analysis. I test whether the vicariance model could significantly shape reptilian current distribution patterns. My results show that dispersal is prevailing for reptiles in China. There are four major biotic elements in reptilian distribution, which are East Xizang, Yunnan-Guizhou Plateau, Taiwan and Hainan, respectively. The test of distributional areas is significantly more clustered than expected by chance, while in another test that closely related species are homogeneously distributed across biotic elements cannot be rejected. Therefore I argued that vicariance might be one of the key processes in patterning reptilian distribution in China. In addition, I develop an improved biotic element analysis in biogeographic studies, by performing biotic element analysis in an iterative manner in order to diagnose more geographically restricted elements until no noise components found. The importance of antecedent selection of distributional data for the subsequent analysis is also discussed. Besides, my study indicates that biodiversity hotspots are not fully overlapped with areas of endemism for reptilians in East Asia.

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Ecology and coexistence of two species of Brachycentrus (Trichoptera) in a Rocky Mountain river

Canadian Journal of Zoology ◽

10.1139/z86-219 ◽

1986 ◽

Vol 64 (7) ◽

pp. 1469-1474 ◽

Cited By ~ 12

Author(s):

F. Richard Hauer ◽

Jack A. Stanford

Keyword(s):

Rocky Mountain ◽

Late Summer ◽

Growth Patterns ◽

Mountain River ◽

Spring Runoff ◽

Winter Conditions ◽

First Instar ◽

Spring Freshet ◽

Early Instar ◽

Peak Runoff

Life-cycle dynamics, growth rates, and relative abundance of Brachycentrus occidentalis and Brachycentrus americanus were studied over a 3-year period in the Flathead River, Montana. Brachycentrus occidentalis appeared as early instar larvae in mid to late summer, grew rapidly during autumn, and reached fourth and fifth instars prior to winter conditions. Most larvae remained active until mid-spring and the onset of spring runoff. Individuals pupated during late April through May and adults emerged after peak runoff in mid-June. Brachycentrus americanus larvae appeared as first instar larvae in autumn and overwintered as early instars. Larvae grew rapidly during spring as temperatures began to rise, but growth was discontinued during spring runoff. Larvae completed growth during summer after the runoff period and emerged in late August and early September. Growth patterns and emergence of both species occurred primarily during fall or spring and late summer, with little growth during winter or spring freshet. Thus growth was associated with quantitatively similar but temporally different periods of organic seston, temperature, and moderate flow.

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