140 research outputs found
Predictive Ability of Value-at-Risk Methods: Evidence from the Karachi Stock Exchange-100 Index
Value-at-risk (VaR) is a useful risk measure broadly used by financial institutions all over the world. VaR has been extensively used to measure systematic risk exposure in developed markets like of the US, Europe and Asia. This paper analyzes the accuracy of VaR measure for Pakistan’s emerging stock market using daily data from the Karachi Stock Exchange-100 index January 1992 to June 2008. We computed VaR by employing data on annual basis as well as for the whole 17 year period. Overall we found that VaR measures are more accurate when KSE index return volatility is estimated by GARCH (1,1) model especially at 95% confidence level. In this case the actual loss of KSE-100 index exceeds VaR in only two years 1998 and 2006. At 99% confidence level no method generally gives accurate VaR estimates. In this case ‘equally weighted moving average’, ‘exponentially weighted moving average’ and ‘GARCH’ based methods yield accurate VaR estimates in nearly half of the number of years. On average for the whole period 95% VaR is estimated to be about 2.5% of the value of KSE-100 index. That is on average in one out of 20 days KSE-100 index loses at least 2.5% of its value. We also investigate the asset pricing implication of downside risk measured by VaR and expected returns for decile portfolios sorted according to VaR of each stock. We found that portfolios with higher VaR have higher average returns. Therefore VaR as a measure of downside risk is associated with higher returns.Downside risk; Emerging Markets; Value-at-Risk.
Managing the Gap Between Actual and Target Capital Structure: An Evidence From Pakistan
Investment framework is one of the most significant components that impact the company’s value. Reliable funding choices for a company generally lead to a capital structure that increases the firm’s value (Abor, 2006). Early studies provide contradictory reviews about a company’s capital structure decisions. This paper investigates the partial adjustment model for a company’s target capital structure. The study also explores how companies operating in different sectors of Pakistani market adjust towards the target capital structure levels. The study also recognizes that an unanticipated share price change also have an effect on the target capital structure. The results indicate that companies do have target leverage and that their adjustment speed varies from sector to sector of the Pakistani market. A typical sector closes more than 50% of the gap between its actual and its target debt ratios within one year
Kinetika raspodjele kanamicina u mula.
The disposition kinetics of kanamycin was investigated following an injection of a single intravenous dose 5 mg/kg body mass in healthy adult female mules. Blood samples collected at various time intervals post-medication were analyzed for kanamycin by microbiological assay. The plasma drug concentration versus time data was best fitted by a biexponential expression. Macro-kinetic parameters were computed for a two-compartment open model. Values for distribution half-life (t1/2á)) and elimination half-life (t1/2 ß) were 0.18 ± 0.26 and 4.39 ± 0.68 h, respectively. The apparent volume of distribution (Vd) was 0.64 ± 0.17 L/kg. Total body clearance (ClB) of the drug was 1.66 ± 0.22 ml/min.kg. Existing dosage of 5 mg/kg body mass at 24 h intervals does not maintain the desired minimum inhibitory concentration (MIC) at the end of proposed dosing intervals. Calculated optimal dosage regimen for kanamycin in mules was 8.73 and 7.45 mg/kg body mass for priming and maintenance, respectively, for a dosage interval of 12 h to maintain the concentration of 2 μg/ml in blood.Istražena je farmakokinetika raspodjele kanamicina u zdravih, odraslih mula nakon jednokratne intravenske primjene u dozi 5 mg/kg tjelesne mase (t.m.) u zdravih odraslih mula. Uzorci krvi uzeti u različitim vremenskim razmacima bili su pretraženi na količinu kanamicina mikrobiološkim testom. Koncentracija lijeka u plazmi u odnosu na vrijeme najviše je odgovarala bieksponencijalnoj krivulji. Za izračunavanje farmakokinetièkih pokazatelja rabljen je dvoprostorni otvoreni model. Rezultati su pokazali da je poluvrijeme raspodjele lijeka (t1/2α) iznosilo 0.18 ± 0.26, a poluvrijeme eliminacije (t1/2β) 4.39 ± 0.68 sati. Prividni volumen raspodjele lijeka (Vd) bio je 0.64 ± 0.17 l/kg, a ukupni klirens (ClB) 1.66 ± 0.22 ml/min/kg. Dozom 5 mg/kg t.m. jedanput na dan nije postignuta željena minimalna inhibicijska koncentracija (MIC) na kraju doznog razmaka. Izračunato je da je optimalna udarna doza kanamicina za mule iznosila 8.73, a doza održavanja 7.45 mg/kg t.m. Pritom se lijek mora primjenjivati svakih 12 sati da bi se postigla koncentracija u krvi 2 mg/ml
Bio-Inspired Solutions and Its Impact on Real-World Problems: A Network on Chip (NoC) Perspective
Bio-inspired solutions are used to solve the real-world problems as they are able to resolve the complex issues. Already existing bio-inspired solutions are reviewed in this chapter which solved the complex engineering problems. Moreover, this chapter also discusses the implementation of biological brain mechanism in Network on Chip to address the fault-tolerant issues. Network on Chip (NoC) is a communication framework for System on Chip (SoC). Due to routers and interconnect failure, NoC suffers from faults. Therefore, bio-inspired solutions help us to recover from these faults. The techniques from the biological brain were implemented in NoC as the brain is fault tolerant and highly adaptive. Results showed that bio-inspired techniques are performing well compared to the traditional fault-tolerant algorithms
Encapsulated virgin coconut oil as a nanoscale in vitro solution against multiple drug resistant Staphylococcus aureus
Abstract Niosomes are excellent nanoscale vehicular systems that can carry a variety of drugs and (bioactive) compounds entrapped inside them. Virgin coconut oil (VCO) is the finest grade of coconut oil that is highly enriched with phenolic content, antioxidant activity and also comprises medium chain triglycerides. In this work, niosomes were encapsulated with VCO synthesized by a simple chemical method. The electron microscopy confirmed that spherical nanostructured lipid carrier molecules with a diameter in the range of 180–190 nm were produced. A zeta potential value of −42 mV was a testimony that these nanovehicles were having good stability. The natural oil loaded nanocarrier spheres proved to be potent antibacterial nano‐antibiotics against multiple drug resistant (MDR) bacteria. The antibacterial activity of these magic nano‐spheres was found to be better than ZnO (metallic oxides) nanoparticles. The nano‐antibiotics resulted in 17, 14 and 12 mm zones of inhibition against methicillin‐resistant Staphylococcus aureus (MRSA), vancomycin‐resistant S. aureus (VRSA) and a (general) MDR strain of S. aureus in contrast to nanoparticles that resulted in zones of inhibitions 7, 8 and 6 mm for the same bacterial strains. Niosomes prove to be an excellent nanocarrier system that can encapsulate a number of bio‐active compounds
Farmakokinetika i optimalno doziranje kanamicina u domaćih preživača.
Pharmacokinetics and optimal dosage of kanamycin were investigated in domestic ruminant species. In indigenous female adult Nili/Ravi buffaloes, Sahiwal cattle, Lohi sheep and Teddy goats, values of elimination half-life (t1/2β)volume of distribution (Vd) and total body clearance (ClB) have been found to be greater than most respective values in their foreign counterparts. Elimination halflife values in domestic ruminants correspond to their respective glomerular filtration rate (GFR) values: the higher the GFR, the shorter the half-life. Comparison of half-life values in domestic ruminants with corresponding total body clearance values showed that shorter half-life should not be equated with higher clearance. To maintain the minimum inhibitory concentration (MIC) of 2 μg/ml of plasma, an optimal dosage regimen of 10.9, 10.2, 12.7 and 15.4 mg/kg body mass for priming and 9.31, 7.79, 11.7 and 14.7 mg/kg body mass for maintenance to be repeated at 12 hour interval have been suggested in buffaloes, cattle, sheep and goats, respectively.Istražena je farmakokinetika i optimalno doziranje kanamicina u domaæih preživača. Poluvrijeme eliminacije lijeka iz plazme (t1/2β), prividni volumen raspodjele (Vd) i ukupni klirens lijeka iz organizma (ClB) bio je veći u odraslih ženki bivola Nili/Ravi, goveda Sahiwal, ovaca Lohi i koza Teddy od odgovarajućih vrijednosti drugih autora. Vrijednosti poluvremena eliminacije lijeka u domaćih preživača odgovarale su vrijednostima stupnja glomerularne filtracije. Što je bio veći stupanj glomerularne filtracije to je bilo kraće poluvrijeme izlučivanja. Usporedba vrijednosti poluvremena izlučivanja s odgovarajućim ukupnim klirensom pokazala je da kraće poluvrijeme izlučivanja ne bi trebalo izjednačiti s većim klirensom. Za održavanje minimalne inhibicijske koncentracije od 2 μg/ml plazme kao optimalna početna doza preporučuje se za bivola 10,9 mg/kg, za govedo 10,2 mg/kg, za ovcu 12,7 mg/kg te za kozu 15,4 mg/kg tjelesne mase. Za održavanje koncentracije lijeka preporučuje se ponovno davanje u razmaku od 12 sati za bivola 9,31 mg/kg, za govedo 7,79 mg/kg, za ovcu 11,7 mg/kg te za kozu 14,7 mg/kg tjelesne mase
Preparation and characterization of silver nanoparticles using aniline
AbstractUV–Vis spectroscopy, transmission electron microscopy (TEM) and selected area electron diffraction (SAED) have been employed to characterize silver nanoparticles (AgNPs) using aniline and silver nitrate as reductant and oxidant, respectively. A broad surface resonance plasmon (SRP) band appears at 400nm, indicating that the AgNPs are spherical. The TEM images show that AgNPs aggregated in an unsymmetrical manner, leading to the formation of beautiful silver nanocrystals. Aniline adsorbed onto the surface of Ag-nanocrystals through electrostatic, van der Walls forces and hydrogen bonding. Cetyltrimethylammonium bromide (CTAB) acted as a stabilizer and/or capping agent
HETEROTIC ESTIMATION AND ADAPTABILITY OF TOMATO HYBRIDS FOR FRUIT YIELD AND ITS RELATED TRAITS IN PAKISTAN.
Current study is emphasizing on the estimation of heterosis for different yield attributing traits and adaptability of tomato hybrids. It was performed in the research area of VCRP, HRI, NARC Islamabad during 2018-2019. Crossing was completed among six parents followed by line × tester. The analyzed data depicted significant differences (P ≤ 0.01) among all the characters.Due to desirable high negative heterotic values hybrids Peto-86 × Nagina and Riograndi × Roma were found suitable for breeding early maturing hybrids. For plant height maximum positive heterosis was observed in Riograndi × Nagina, for no. of cluster/plant in Naqeeb × Roma, for traits like flower cluster-1, fruit cluster-1, fruit length & width and single fruit weight in Naqeeb × Continental while for yield Riograndi × Continental showed maximum heterosis. Therefore among 9 tested hybrids Naqeeb × Continental was found to be highly preferable and recommended for utilization in different breeding programmes
Antihyperlipidaemic Efficacy of Trachyspermum ammi in Albino Rabbits
The objective of the present study was to investigate the antihyperlipidaemic efficacy of Trachyspermum ammi (L) Sprague, seed (Ajowan) powder in albino rabbits. Hyperlipidaemia was induced with butter ad libitum and oral intubation of cholesterol 400 mg/kg body weight. Simvastatin, (Tablet survive®) was used as a synthetic cholesterol lowering drug. The results suggest that 2 g/kg T. ammi seed powder produced hypolipidaemic activity, rendering 49%, 53%, 71% and 63% reduction in total lipids, triglycerides, total cholesterol and LDL-cholesterol, respectively. However, at this dosage level 62% increase in the value of HDL-cholesterol was induced by T. ammi seed powder. Nonetheless, 0.5 g/kg and 1 g/kg T. ammi seed powder did not show antihyperlipidaemic activity. T. ammi seed powder at the rate of 2 g/kg and simvastatin (0.6 mg/kg body weight) were equally effective in treating hyperlipidaemia in albino rabbits. Moreover, this dosage level also significantly reduced the cholesterol content of liver tissue. It can be anticipated that the lipid lowering mechanism may involve enhanced removal or catabolism of lipoproteins, inhibition of HMG COA reductase, and/or inhibition of lysosomal lipid hydrolytic enzymes secreted by the liver
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