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P>The influence of parasitism on first-year growth and recruitment success of two cyprinid species in the Yorkshire Ouse catchment, England, was investigated using a 14-year dataset. This study demonstrated a significant role of p...
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P>The influence of parasitism on first-year growth and recruitment success of two cyprinid species in the Yorkshire Ouse catchment, England, was investigated using a 14-year dataset. This study demonstrated a significant role of parasitism in growth and recruitment success of roach, Rutilus rutilus (L.), and European chub, Squalius cephalus (L.) populations. Muscle infections by Bucephalus polymorphus Baer (Digenea), Myxobolus pseudodispar Gorbunova (Myxozoa) and Myxobolus pfeifferi Thelohan were considered important, with significant relationships between these parasites and year-class strength and age-0 fish length. Other parasites, such as Phyllodistomum sp. and Goussia sp., were implicated in host success to a lesser extent. Parasitism may be a major factor in recruitment and account for a high proportion of the variation in year-class strength, although this varied among locations.
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Small and medium businesses (SMEs) are critical to any country’s national economic development. On the other hand, SMEs confront a considerable difficulty in succession planning: the lack of or inefficiency/ineffectiveness of suc...
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Small and medium businesses (SMEs) are critical to any country’s national economic development. On the other hand, SMEs confront a considerable difficulty in succession planning: the lack of or inefficiency/ineffectiveness of succession planning. As a result, this quantitative correlational study aimed to evaluate the influence of succession planning on the growth of Small and Medium Enterprises (SMEs) in the Brong Ahafo region of Ghana. To reach the research goal, the study used a quantitative correlational research design. Data were collected from 140 respondents involved in SMEs from nine district s and municipal assemblies from the Bono, Ahafo and Bono East Regions of Ghana. The results revealed that most of the respondents, 113 (80.64%), ag reed that employees or possible successors might leave the organisation for a better offer and 106 (75.71%) respondents indicated that owners of SMEs do not think about succession plan until there is a crisis. The results also showed that succession plan explains nearly (50%); thus, half the chance s of survival of an SME in the Bono, Ahafo and Bono East regions are dependent on succession planning. There was a significant difference in succession plan practices a mong the different year groups of SMEs. The result also demonstrated no statistically significant difference in the service and manufacturing industries’ succession planning practices among the SMEs surveyed. It is recommended that business owners, policymakers and the state should support SMEs in succession planning development. If possible, succession planning should be part of the school curriculum and entrepreneurship training programmes in schools and business institutes. This will build the capacity of prospective business owners and create awareness about the effects of succession planning on the growth of organisations.
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The three-year recession may have ended, but much of the world still struggles to recover. It was against this backdrop that Steve Forbes, chairman of Forbes Media, opened the 5th International Gemological Symposium with his keynote address.
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Following a major phase of reinvestment into five new research platforms, and a significant capital development programme, HortResearch recorded a tax paid profit of 1.5 million dollar for the year ended 30 June 2001. Total shareh...
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Following a major phase of reinvestment into five new research platforms, and a significant capital development programme, HortResearch recorded a tax paid profit of 1.5 million dollar for the year ended 30 June 2001. Total shareholder value for thefinancial year 2001 has reached 48.09 million dollar. HortResearch CEO Dr Ian Warrmgton, said HortResearch has followed a policy of strongly investing in new facilities and equipment to support research and development. "This has seen the establishment of better buildings and over 4 million dollar being invested in modern equipment, instruments and plant over the last 12 months. In early 2001 a state-of-the-art 6.2 million dollar research and development complex was opened at the HortResearch Hawke' Baysite. Another new, purpose-build complex is Hearing completion at the Ruakura site in Hamilton."
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In this article we describe the 20-year history of Mitacs, which is a unique Canadian organization promoting innovation through the deployment of highly qualified talent-namely, graduate students-in companies and not-for-profit or...
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In this article we describe the 20-year history of Mitacs, which is a unique Canadian organization promoting innovation through the deployment of highly qualified talent-namely, graduate students-in companies and not-for-profit organizations. What began as a research hub connecting mathematics to industry has evolved into a national organization providing a bridge from all disciplines to the private sector across Canada and creating mobility opportunities between Canada and the rest of the world. Mitacs is an important legacy arising from the creativity and enterprising spirit of the Canadian mathematical sciences community.
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Capsule Even though most other pairs in the colony had finished breeding, late breeders that lost eggs and relaid were successful in rearing young.
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Barnacle Geese Branta leucopsis first colonised the Russian arctic island of Kolguev in the early 1980s, since when their numbers have steadily grown. Initial colonies were founded on fox-free coastal sand spits, but by the mid-19...
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Barnacle Geese Branta leucopsis first colonised the Russian arctic island of Kolguev in the early 1980s, since when their numbers have steadily grown. Initial colonies were founded on fox-free coastal sand spits, but by the mid-1990s large colonies (>5,000 breeding pairs) had become established in the Peschanka River delta, reaching 45,000 breeding pairs by the mid-2000s. Subsequendy, numerous new smaller colonies (mean ± s.d. = 12 ± 6 nesting pairs, range = 1—54, n — 18 colonies) started to increase in numbers in the central part of the island, initially associated with c. 30% of all known Peregrine Falcon Falcoperegrinus nests in the study area. The overall population size and number of inland colonies continued to grow, and by 2011—2012 all24 known Peregrine Falcon nests had Barnacle Goose colonies (mean colony size = 54 ± 40 pairs, range = 1—133, n — 13 colonies). White-fronted Geese Anser albifrons and Tundra Bean Geese Anserfabalis rossicus formerly recorded nesting in dense colonies around Peregrine Falcon nests no longer did so, apparently having been expelled from core areas by the earlier nesting and more aggressive Barnacle Geese. The hatching success of Barnacle Geese nesting in the open sedge-moss bogs of central Kolguev (first occupied in 2011—2012) was no different to those associating with Peregrine Falcons (73% and 75% respectively). During brood rearing and moulting, Barnacle Geese share feeding habitats with other goose species. Should their numbers continue to growon the island, further overgrazing of foraging habitats may increase competition between Barnacle Geese and White-fronted Geese for food, both in brood-rearing and in moulting habitats.
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The study was conducted to investigate the effects of winter crops succession on maize growth and productivity, at Salahaddin University, Erbil, Iraq, during fall and a winter season of 2016-2017. During both fall seasons, the fie...
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The study was conducted to investigate the effects of winter crops succession on maize growth and productivity, at Salahaddin University, Erbil, Iraq, during fall and a winter season of 2016-2017. During both fall seasons, the field was completely planted with maize, afterwards, at winter season, three crops were selected namely canola, chickpea and wheat as well as a fallow plot in factorial randomized complete block design. The studied vegetative characters were plant height, ear height and stem diameter, while the productive characters were ear diameter, grain yield, 300-kernels weight of ear's base and biological weight. The highest plant height was after fallow and ear height and stem diameter after chickpea with 232.96, 90.87 and 2.46 cm respectively. The ear diameter and grain yield were maximum (2.69 cm, 13.46 t/ha) after chickpea. The 300-kernels weight of ear's base and biological weight were maximum in fallow after canola (93.88 and 491.43 g). The physiological characters, leaf area and leaf area index demonstrated the highest values after canola (6342.41 cm~2 and 3.38 respectively).
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There are many ecological advantages to attaining a large body size as fast as possible (such as reduced risks of being caught by predators or increased reproductive success). However, studies in several taxa indicate that fast gr...
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There are many ecological advantages to attaining a large body size as fast as possible (such as reduced risks of being caught by predators or increased reproductive success). However, studies in several taxa indicate that fast growth in itself can have negative as well as positive effects. There appears to be a link between accelerated growth and lifespan: rapid growth early in life is associated with impaired later performance and reduced longevity. In this review we assess the evidence for such within individual trade-offs between growth rate and lifespan, and the potential physiological mechanisms that might underlie them. We discuss the fitness implications of any reduction in lifespan, and point out that certain environmental circumstances may favour a 'grow fast and die young' strategy if this increases overall reproductive success. However, investigation of the intra-specific relationships among growth rate, lifespan and fitness is not straightforward; few studies have controlled for confounding variables such as adult body size or duration of the growth period, and none to date have measured fitness in an appropriate ecological setting. We suggest a number of experimental approaches that might allow the true relationships between growth rate and future performance to be elucidated.
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Assessing the factors that may contribute to rarity in flowering plants is important in preserving biodiversity. One method of examining these factors is through comparisons of rare species to more common congeners. While these st...
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Assessing the factors that may contribute to rarity in flowering plants is important in preserving biodiversity. One method of examining these factors is through comparisons of rare species to more common congeners. While these studies are fairly common, most focus on comparisons of intrinsic factors, such as growth and dispersal rates and other physical attributes. In contrast, this study examined the effects of extrinsic factors, specifically herbivory by white-tailed deer (Odocoileus virginianus) and competition with an invasive vine, Lonicera japonica, on a rare forest herb, Trillium reliquum and its more common congeners, Trillium maculatum and Trillium cuneatum. We used a factorial design involving deer exclusion and honeysuckle removal to determine effects on relative growth of rare and common trilliums. We found that a common trillium was more susceptible to herbivory than T. reliquum in one of the three sites with a similar trend in a second site and no effect in the third. Deer also significantly reduced relative leaf area (a measure of growth) for all species, reduced the probability of subadult transitions to reproductives, and increased the probability of non-emergence in two sites. While deer had a significant effect in this study, there was no detectable effect of honeysuckle presence on growth for any species of trillium during this time period. Our results show that the long-term management of white-tailed deer will be important to the conservation of spring ephemeral herbs such as T. reliquum, T. cuneatum, and T. maculatum.
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