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Literature on firms’ entry and exit decisions provides empirical evidence that industries with many exits also have many entries. We present a paper that merges some different approaches to the entry and exit of firms and which proposes a new method for looking at the entrepreneurial decision. Our model theoretically supports what empirical evidence has shown and holds; that databases are not yet developed enough to understand the whole exit process. We demonstrate that the possibility of recovering some share of investment costs makes entry more than just a production decision. Within a defined time horizon, a firm can enter the market despite making a loss from production output since the firm’s return consists of both sales and investment cost recovery. Entry may be the optimal strategy even when the unit cost is higher than the market price.

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Summary  

The present work proposes a methodology for a rapid determina­tion of the tritium content in urine. The urine is treated with active carbon and tritium is determined by liquid scintillation counting. Different kinds of active carbon were experimented for the metabolites removal from urine samples. The counting efficiency was calculated by a quench curve using yellow food dye as a quenching agent. It was obtained a procedure which maintained a good reproducibility, low uncertainty and detection limit of 7 Bq/l (10 ml of urine, 120 minutes of counting time and efficiency of 23.9%).

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In this paper we consider the problem of local uniform equiconvergence with trigonometric series of orthogonal expansions in a system of eigenfunctions of the Sturm-Liouville operator with real potential q(x) ∈ L 1(0, 1), for the function f(x) from the classes W 1 1 (0, 1) and W 1 r (0, 1) (r ≧ 1), f(0) = f(1) = 0. Rate of equiconvergence on every compact subset of (0, 1) is established. Rate of equiconvergence depends on the module of continuity of potential.

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A new concept of Walsh-Lebesgue points is introduced for higher dimensions and it is proved that almost every point is a modified Walsh-Lebesgue point of an integrable function. It is shown that the Walsh-Fejér means σ n f of a function fL 1[0, 1) d converge to f at each modified Walsh-Lebesgue point, whenever n→∞ and n is in a cone. The same is proved for other summability means, such as for the Weierstrass, Abel, Picard, Bessel, Cesàro, de La Vallée-Poussin, Rogosinski and Riesz summations.

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The aim of this study was to evaluate the ability of two synthetic GnRH analogues, goserelin and leuprolide, to induce ovulation in rabbit does using intravaginal administration. A total of 252 primiparous lactating does were randomly divided into five groups that, at the time of insemination, received the following treatments for ovulation induction: 1 µg of buserelin administered intramuscularly (control group), 5 µg of goserelin added to the semen dose (Group G5), 10 µg of goserelin added to the semen dose (Group G10), 5 µg of leuprolide added to the semen dose (Group L5), and 10 µg of leuprolide added to the semen dose (Group L10). The kindling rate was 80.5% in Group G10 and 75.0% in Group L10; these values are comparable to the kindling rate obtained in the control group (85.9%). The kindling rates in Groups G5 and L5 were significantly lower than in the control group (60.0%, 54.2% and 85.9%, respectively). The number of live-born rabbits was not significantly affected by the ovulation induction treatment. As regards the total number of rabbits born the only significant difference was observed between Groups G5 and L5. This study shows the possibility of inducing ovulation in rabbits by adding goserelin and leuprolide directly to the semen dose.

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Abstract  

We study the continuity and smoothness properties of functions fL 1([0, ∞)) whose sine transforms
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\hat f_s$$ \end{document}
and cosine tranforms
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\hat f_c$$ \end{document}
belong to L 1([0,∞)). We give best possible sufficient conditions in terms of
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\hat f_s$$ \end{document}
and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\hat f_c$$ \end{document}
to ensure that f belongs to one of the Lipschitz classes Lip α and lip α for some 0 < α ≤ 1, or to one of the Zygmund classes Zyg α and zyg α for some 0 < α ≤ 2. The conditions given by us are not only sufficient, but also necessary in the case when the sine and cosine transforms are nonnegative. Our theorems are extensions of the corresponding theorems by Boas from sine and cosine series to sine and cosine transforms.
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The beneficial effects of different lighting programmes on the incidence of ascites was investigated in an experiment with 360 three-day-old male broiler chickens. At 3 days of age, chicks were randomly divided over three rooms in a high-altitude farm, 2000 m above sea level. During days 14 to 28 ambient temperature decreased during the night but the minimum temperature did not descend below 15°C. In the first room the continuous lighting schedule (CL, 23L:1D) was maintained and in the second room an intermittent lighting schedule (IL, 1L:3D), repeated six times daily, was imposed from 3 days of age. In the third room, an increasing photoperiod schedule (IP, 4 to 14 days, 6L:18D; 15 to 21 days, 10L:14D; 22 to 28 days, 14L:10D; 29 to 35 days, 18L:6D; 36 to 42 days, 23L:1D) was provided. Mortality associated with right ventricular failure and ascites was numerically lower in birds reared under the IL and IP schedules compared to birds reared under the CL schedule, which can be attributed to the temporary reduction in relative growth and feed intake in IL and IP birds. It was concluded that the beneficial effect of lighting schedules could be due to a reduced metabolic rate as a consequence of the altered growth trajectory, as also reflected in the lower haematocrit and plasma T3 levels of IL and IP birds compared to CL birds.

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Mutations in the HIV-1 genes associated with resistance to antiretroviral drugs were detected also in primary HIV infected individuals who did not receive antiretroviral treatment. Drug resistance genotyping of HIV pol gene was done by in situ DNA hybridization using a Line Probe Assay and by direct sequencing. Viral variants harbouring resistance mutations such as: M41, T69R, K70R, M184V, T215Y in the pol gene were detected in 14% of the subjects. HIV mutants resistant to NRT inhibitors were found in 10 and 20% of patients infected before and after the year 2000, respectively. Multiple drug resistant viruses (2–3 drug classes) were present in 3.5% of the mainly recently infected patients. In protease gene only minor resistant mutations were found such as L10I and A71V.These findings indicate the evolution of drug resistance showing a correlation with the time of introduction of combination therapy in our country, where more than 70% of HIV infections were by homo/bisexual transmission.This confirms the transmission of drug-resistant HIV shown by genotype testing during primary infection in therapy-naive patients and initiates serious clinical and public health consequences.

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Abstract  

Studies have been made of loose water tritium (LWT) distribution and behavior in the soil samples taken from the region within a radius of 2 km to the HWRR stack of CIAE. The analytical results show that the LWT concentrations in most soil samples of the region are in the range from 24.8 Bq/l (3.6 Bq/kg) to 116 Bq/l (16.0 Bq/kg) with an average value of 58.1±24.8 Bq/l (10.3±4.5 Bq/kg). There are two areas with a higher LWT content; the first one (4.61 · 104 m2) is located near HWRR with ahighest LWT concentration of 287 Bq/l (55.8 Bq/kg) and the second one (3.27 ·105 m2) is located near Lab. A with a highest LWT concentration of 2.35 · 104 Bq/l (2.56 · 103 Bq/kg). It is estimated that the LWT inventories deposited in soil of the two areas are about 1.52 · 109 Bq and 1.42 · 1010 Bq, respectively. The analytical results have been evaluated by comparing the possible tritium intake of the human body with the annual limit of intake recommended by ICRP, it can be concluded that the operations of all the nuclear facilities releasing tritium in CIAE are safe without causing any notable tritium contamination.

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There is little information on interaction between productivity, stability and drought resistance of crop. This problem is very important in Kazakhstan, where the most of the agricultural area is located in arid and semiarid regions. In this context the genotype × environment interaction (GEI) is of major importance to the plant breeders in developing improved drought resistant cultivars. In this study GEI and stability parameters of recombinant inbred lines (RILs) has been determined by field testing at three contrasting environments. The comparison of the performance and stability of the lines L3, L10, L5, L1 indicated that this breeding material tended to display better performance for main of productivity traits and stability for plant grain yield as compared with other RILs and parental forms. There was positive association between high leaf Relative Water Content (RWC), low leaf Relative Water Loss (RWL) and yield stability. Both physiological parameters (RWC and RWL) are good indicators of drought adaptation by wheat genotypes. A comparison of glume pubescent and unpubescent lines has shown close negative correlation for spike RWL and spike RWC of all pubescent RILs (R2= -0.845). So the glume pubescence can be used as a morphological marker and indirect criterion for selection of drought resistant genotypes. As a result several promising lines combining high yield stability and drought resistance has been selected and used in breeding program.

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