RESUMO
Capital structure is an integral part of the corporate finance that sources the funds to finance growth and operations. Managers always have to maintain value of the firm to be higher than the cost of capital in order to maximize the shareholders wealth. Empirical studies have used sources of finance like debt and equity as variables of capital structure. A choice between debt and equity finance analyzes the firm's ability to perform under the financially constrained environment to attain the sustainable growth. Therefore, it gives rise to a dire need to estimate the cost of capital precisely. We examined the capital structure of top ten market capitalization of the stock markets included in MSCI Emerging index with the use of artificial neural networks, support vector regression, and linear regression in forecasting methods. The capital structure is measured as the proportion of total debt over total equity (Tang et al., 1991). Other financial ratios such as profitability, liquidity, solvent, and turnover ratios were considered as drivers of the capital structure. Applying logistic and hyperbolic tangent activation functions, it was concluded that ANN has a great potential of replacing other traditional forecasting models with the nonstationary data. This research contributes with a new dimension for estimation through different activation functions. There is a possibility of ANN dominance as compared to the other models applied for predictability in financial markets.
Assuntos
Administração Financeira , Máquina de Vetores de Suporte , Redes Neurais de Computação , SolventesRESUMO
UNLABELLED: We hypothesized that chronic exposures to traffic combustion products may lower bone mineral density (BMD). We found that proximity to freeways was associated with reduced BMD. Our findings suggest that traffic-related pollution may contribute to the occurrence of osteopenia and osteoporosis. INTRODUCTION: Adults residing in rural areas have been linked with higher BMD. We aimed to determine if this difference is due in part to air pollution by examining the relationships between traffic metrics and ambient air pollution with total body and pelvic BMD. METHODS: Mexican American adults (n = 1,175; mean 34 years; 72 % female) who had participated in the BetaGene study of air pollution, obesity, and insulin resistance were included in this analysis. Total body and pelvic BMD were estimated using dual-energy X-ray absorptiometry. Traffic and ambient air pollutant exposures were estimated at residences using location and ambient monitoring data. Variance component models were used to analyze the associations between residential distance to the nearest freeway and ambient air pollutants with BMD. RESULTS: Residential proximity to a freeway was associated with lower total body BMD (p-trend = 0.01) and pelvic BMD (p-trend = 0.03) after adjustment for age, sex, weight, and height. The adjusted mean total body and pelvic BMD in participants living within 500 m of a freeway were 0.02 and 0.03 g/cm(2) lower than participants living greater than 1,500 m from a freeway. These associations did not differ significantly by age, sex, or obesity status. Results were similar after further adjustment for body fat and weekly physical activity minutes. Ambient air pollutants (NO2, O3, and PM2.5) were not significantly associated with BMD. CONCLUSIONS: Traffic-related exposures in overweight and obese Mexican Americans may adversely affect BMD. Our findings indicate that long-term exposures to traffic may contribute to the occurrence of osteoporosis and its consequences.
Assuntos
Poluição do Ar/efeitos adversos , Osteoporose/etiologia , Emissões de Veículos/toxicidade , Absorciometria de Fóton/métodos , Adulto , Poluição do Ar/análise , Antropometria/métodos , Densidade Óssea/fisiologia , California/epidemiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Feminino , Humanos , Masculino , Americanos Mexicanos/estatística & dados numéricos , Veículos Automotores , Osteoporose/etnologia , Osteoporose/fisiopatologia , Sobrepeso/complicações , Sobrepeso/etnologia , Ossos Pélvicos/fisiopatologia , Características de Residência/estatística & dados numéricos , Fatores Socioeconômicos , Emissões de Veículos/análiseRESUMO
A study of 320 samples of mammary quarters from cows in 40 dairy farms around Santa Fe city during 1977-1978 was made. The samples were selected based on clinical examination and California Mastitis Test (GMT). High percentage of subclinical mastitis was found. The etiological agents most frequently isolated were Staphylococcus aureus (54,1%), Streptococcus agalactiae (23.4%) and Pseudomonas aeruginosa (13,2%). A winter increment of S. aureus (48,1%) and P. aeruginosa (3,7% and 22,5%) was observed. But S. agalactiae did not experiment considerable variation (26,8% and 20% throughout the year. The sensitivity to antibiotics of some strains decreased in winter specially in S. aureus and P. aeruginosa (61,5% and 38,9%), and some biochemical properties related with their virulence increased. Penicillin in milk was not detected, but the levels of contamination by non specific inhibitory substances were very high (40%). Besides it was found a great contamination with aerobic sporeforming bacteria in these samples, being Bacillus coagulans (59,1%), B. polymyxa (26,1%) and B. sphaericus (9,5%) the most frequent.
Assuntos
Mastite Bovina/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Streptococcus agalactiae/isolamento & purificação , Animais , Antibacterianos/farmacologia , Bovinos , Resistência Microbiana a Medicamentos , Feminino , Leite/microbiologiaRESUMO
A study of 320 samples of mammary quarters from cows in 40 dairy farms around Santa Fe city during 1977-1978 was made. The samples were selected based on clinical examination and California Mastitis Test (GMT). High percentage of subclinical mastitis was found. The etiological agents most frequently isolated were Staphylococcus aureus (54,1
), Streptococcus agalactiae (23.4
) and Pseudomonas aeruginosa (13,2
). A winter increment of S. aureus (48,1
) and P. aeruginosa (3,7
and 22,5
) was observed. But S. agalactiae did not experiment considerable variation (26,8
and 20
throughout the year. The sensitivity to antibiotics of some strains decreased in winter specially in S. aureus and P. aeruginosa (61,5
and 38,9
), and some biochemical properties related with their virulence increased. Penicillin in milk was not detected, but the levels of contamination by non specific inhibitory substances were very high (40
). Besides it was found a great contamination with aerobic sporeforming bacteria in these samples, being Bacillus coagulans (59,1
), B. polymyxa (26,1
) and B. sphaericus (9,5
) the most frequent.
RESUMO
A study of 320 samples of mammary quarters from cows in 40 dairy farms around Santa Fe city during 1977-1978 was made. The samples were selected based on clinical examination and California Mastitis Test (GMT). High percentage of subclinical mastitis was found. The etiological agents most frequently isolated were Staphylococcus aureus (54,1
) and Pseudomonas aeruginosa (13,2
). A winter increment of S. aureus (48,1
) and P. aeruginosa (3,7
throughout the year. The sensitivity to antibiotics of some strains decreased in winter specially in S. aureus and P. aeruginosa (61,5
), and some biochemical properties related with their virulence increased. Penicillin in milk was not detected, but the levels of contamination by non specific inhibitory substances were very high (40
). Besides it was found a great contamination with aerobic sporeforming bacteria in these samples, being Bacillus coagulans (59,1
) and B. sphaericus (9,5
) the most frequent.