scholarly journals Post-Fire Demography, Growth, and Control of Eucalyptus globulus Wildlings

Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 156
Author(s):  
Joaquim S. Silva ◽  
Mauro Nereu ◽  
Simão Pinho ◽  
Luís Queirós ◽  
Cláudio Jesús ◽  
...  
Keyword(s):  
Growth Rate ◽  
Eucalyptus Globulus ◽  
Control Method ◽  
Management Strategies ◽  
High Growth ◽  
Maximum Temperature ◽  
Ecological Problem ◽  
Introduced Range ◽  
One Year ◽  
Mechanical Cutting

Several eucalypt species are known for their capacity to massively regenerate through seeds in recently burned areas, becoming an ecological problem in regions where the species is not native. Here we study the demography and the development of highly dense Eucalyptus globulus wildling populations established one year after a fire and test two methods to control these populations. We monitored five mixed E. globulus stands across one year, in Central Portugal. We established a set of plots in each stand, with three treatments: mechanical cutting, herbicide spraying and no disturbance (control plots). Herbicide was applied in four concentrations. We tagged randomly selected plants in the control plots to monitor their growth. The initial mean wildling density was 322,000 plants ha−1, the highest ever recorded in the introduced range. Wildling density was significantly dependent on the density of surrounding adult E. globulus trees. Wildling density in control plots decreased 30% in one year, although showing positive variations over time because of new recruitment. Despite seasonal growth differences, wildlings showed a high growth rate throughout the year, reaching 15.6 cm month−1 in the summer. The growth rate of tagged wildings was positively affected by solar radiation and negatively affected by evapotranspiration and maximum temperature. Mechanical cutting reduced wildling density by 97% while herbicide treatment reduced density between 80% (for the lowest concentration) and 99% (for the highest concentration). Herbicide-treated plants were more likely to resprout than cut plants. Regardless of the control method adopted (cutting or herbicide), management strategies should include the follow-up of the treated areas, to detect the establishment of new recruits and resprouting.

How Fast Can Firms Grow?

2014 ◽  
Vol 234 (2-3) ◽  
Author(s):  
Johann Peter Murmann ◽  
Jenny Korn ◽  
Hagen Worch
Keyword(s):  
Growth Rate ◽  
Mergers And Acquisitions ◽  
Growth Rates ◽  
Maximum Rate ◽  
High Growth ◽  
Organizational Structures ◽  
Sales Growth ◽  
Growth Firms ◽  
Simple Question ◽  
One Year

SummaryBuilding on recent research on dynamic, high-growth firms - so-called “gazelles” - this paper explores a simple question that is important in both theoretical and practical terms: What is the fastest rate at which firms can grow? Based on a sample of seven high-growth firms (Cisco, GM, IBM, Microsoft, Sears, Starbucks, and US Steel), we find that 162% is the maximum sales growth rate in any one year that an established company can grow without mergers and acquisitions, while the maximum rate of employee growth is approximately 115% even including some mergers and acquisitions. All of the companies in our sample attained a maximum sales growth rate of above 50%, with most hovering around 75%. Furthermore, the firms’ growth rates exhibit similar patterns. No company experienced its maximum sales growth rate toward the latter part of its history. Every company experienced its slowest employee growth rate after attaining its maximum employee growth rate, usually within a decade of one another. Most importantly, all firms show an average sales growth that exceeds the average employee growth. This finding is an indication that successful growing firms have a superior capability to continuously improve employment efficiency and adjust organizational structures to suit an increasing workforce.

Exploring SiC Growth Limitation of Vapor-Liquid-Solid Mechanism when Using Two Different Carbon Precursors

2013 ◽  
Vol 740-742 ◽  
pp. 323-326
Author(s):  
Kassem Alassaad ◽  
François Cauwet ◽  
Davy Carole ◽  
Véronique Soulière ◽  
Gabriel Ferro
Keyword(s):  
Growth Rate ◽  
High Growth ◽  
High Growth Rate ◽  
Carbon Precursor ◽  
Growth Limitation ◽  
Vapor Liquid Solid ◽  
Partial Pressures ◽  
Vapor Liquid Solid Mechanism ◽  
Vls Growth ◽  
Vapor Liquid

Abstract. In this paper, conditions for obtaining high growth rate during epitaxial growth of SiC by vapor-liquid-solid mechanism are investigated. The alloys studied were Ge-Si, Al-Si and Al-Ge-Si with various compositions. Temperature was varied between 1100 and 1300°C and the carbon precursor was either propane or methane. The variation of layers thickness was studied at low and high precursor partial pressure. It was found that growth rates obtained with both methane and propane are rather similar at low precursor partial pressures. However, when using Ge based melts, the use of high propane flux leads to the formation of a SiC crust on top of the liquid, which limits the growth by VLS. But when methane is used, even at extremely high flux (up to 100 sccm), no crust could be detected on top of the liquid while the deposit thickness was still rather small (between 1.12 μm and 1.30 μm). When using Al-Si alloys, no crust was also observed under 100 sccm methane but the thickness was as high as 11.5 µm after 30 min growth. It is proposed that the upper limitation of VLS growth rate depends mainly on C solubility of the liquid phase.

scholarly journals Care for Patients with Type 2 Diabetes in a Random Sample of Community Family Practices in Ontario, Canada

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Gina Agarwal ◽  
Janusz Kaczorowski ◽  
Steve Hanna
Keyword(s):  
Best Practices ◽  
Diabetes Care ◽  
Diabetes Management ◽  
Management Strategies ◽  
Chart Audit ◽  
Pressure Reading ◽  
International Data ◽  
One Year ◽  
Control And Management

Objective. Diabetes care is an important part of family practice. Previous work indicates that diabetes management is variable. This study aimed to examine diabetes care according to best practices in one part of Ontario. Design and Participants. A retrospective chart audit of 96 charts from 18 physicians was conducted to examine charts regarding diabetes care during a one-year period. Setting. Grimsby, Ontario. Main Outcome Measures. Glycemic screening, control and management strategies, documentation and counselling for lifestyle habits, prevalence of comorbidities, screening for hypertension, hyperlipidemia, and use of appropriate recommended preventive medications in the charts were examined. Results. Mean A1c was within target (less than or equal to 7.00) in 76% of patients (ICC = −0.02), at least 4 readings per annum were taken in 75% of patients (ICC = 0.006). Nearly 2/3 of patients had been counselled about diet, more than 1/2 on exercise, and nearly all (90%) were on medication. Nearly all patients had a documented blood pressure reading and lipid profile. Over half (60%) had a record of their weight and/or BMI. Conclusion. Although room for improvement exists, diabetes targets were mainly reached according to recognized best practices, in keeping with international data on attainment of diabetes targets.

scholarly journals Thermoregulation in colonies of africanized and hybrids with Caucasian, Italian and Carniolan Apis mellifera honey bees

1999 ◽  
Vol 42 (4) ◽  
Author(s):  
Vagner de Alencar Arnaut de Toledo ◽  
Regina Helena Nogueira-Couto
Keyword(s):  
Apis Mellifera ◽  
Honey Bees ◽  
Maximum Temperature ◽  
Tropical Region ◽  
Internal Temperature ◽  
Africanized Honey Bees ◽  
Significant Difference ◽  
The Mean ◽  
One Year ◽  
Brood Nest

This experiment was carried out to study the internal temperature regulation of a colony of Africanized honey bees (AFR), compared with hybrid Caucasian (CAU), Italian (ITA), and Carniolan (CAR) bees, during the period of one year and different size hives located in a sub-tropical region. The instant internal temperature, 33.7 ± 1.5° C for the AFR, 33.5 ± 1.4° C for the CAU, 33.7 ± 1.5° C for the ITA and 33.8 ± 1.4° C for the CAR, did not show any significant difference (P>0.05). The maximum temperature (36.1 ± 2.3° C) was statistically different (P<0.05) from the minimum (27.6 ± 5.3° C). There was no difference (P>0.05) in the mean internal temperature, between the nucleus (31.7 ± 6.3° C) and the brood nest (32.1 ± 5.3° C) measured between two and four o'clock in the afternoon.

Very High Growth Rate of 4H-SiC Using MTS as Chloride-Based Precursor

2008 ◽  
Vol 600-603 ◽  
pp. 115-118 ◽  
Author(s):  
Henrik Pedersen ◽  
Stefano Leone ◽  
Anne Henry ◽  
Franziska Christine Beyer ◽  
Vanya Darakchieva ◽  
...  
Keyword(s):  
Growth Rate ◽  
Linear Dependence ◽  
Growth Rates ◽  
Molar Fraction ◽  
High Growth ◽  
High Growth Rate ◽  
Epitaxial Layers ◽  
Single Precursor ◽  
Very High

The chlorinated precursor methyltrichlorosilane (MTS), CH3SiCl3, has been used to grow epitaxial layers of 4H-SiC in a hot wall CVD reactor, with growth rates as high as 170 µm/h at 1600°C. Since MTS contains both silicon and carbon, with the C/Si ratio 1, MTS was used both as single precursor and mixed with silane or ethylene to study the effect of the C/Si and Cl/Si ratios on growth rate and doping of the epitaxial layers. When using only MTS as precursor, the growth rate showed a linear dependence on the MTS molar fraction in the reactor up to about 100 µm/h. The growth rate dropped for C/Si < 1 but was constant for C/Si > 1. Further, the growth rate decreased with lower Cl/Si ratio.

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