Problems in the Analysis of Binary Mixture Distributions

In Chapter 1, a finite mixture distribution is defined and background literature is briefly mentioned. A theorem is proved in Chapter 2 which states that if three density functions are proper mixtures of the same two components then one of them is a proper mixture of the other two. It is shown, with the help of a counter example, that the converse of this theorem is not necessarily true. In Chapter 3, two critical papers are reviewed. In Chapter 4, a distance function, based on the necessary condition of this theorem, is defined which 'measures' the deviation from the hypothesis that one of the densities is a proper mixture of the other two. The expressions for the mean and variance of this distance function are calculated for continuous data. Simulations are carried out to generate values of the distance function for a number of cases (null as well as non-null). For the several values of the distance function thus obtained the sample mean and sample variance were calculated and compared with the theoretical values obtained from the above mentioned expressions. The distribution of the distance function is considered and it is shown, diagrammatically, that the logarithm of this distance function is approximately normally distributed. Finally, in this chapter, a test of the null hypothesis is suggested. In Chapter 5, expressions for the mean and variance of the distance function are discussed for discrete data. A simulation study is carried out and a 'parametric' test of the null hypothesis is suggested and carried out on several data sets. Also, a non-parametric test of the null hypothesis is suggested and carried out on the same data sets. Finally, in this chapter, the various tests suggested are also applied to some fish data. In Chapter 6, a Monte Carlo test based on the above-mentioned distance function is introduced. In Chapter Via theorem is proved which determines another necessary condition for three densities to be proper mixtures of the same two components. In Chapter 8, the theory and methods developed in this thesis (which are applicable only to the case of three density functions) are generalised to the case where we have more than three density functions. Finally, finite mixtures having more than two components are discussed in some detail

Factors affecting ventriculoperitoneal shunt survival in adult patients

Background: Ventriculoperitoneal (VP) shunt insertion remains the mainstay of treatment for hydrocephalus despite a high rate of complications. The predictors of shunt malfunction have been studied mostly in pediatric patients. In this study, we report our 11-year experience with VP shunts in adult patients with hydrocephalus. We also assess the various factors affecting shunt survival in a developing country setting.Methods: A retrospective chart analysis was conducted for all adult patients who had undergone shunt placement between the years 2001 and 2011. Kaplan-Meier curves were used to determine the duration from shunt placement to first malfunction and log-rank (Cox-Mantel) tests were used to determine the factors affecting shunt survival.Results: A total of 227 patients aged 18-85 years (mean: 45.8 years) were included in the study. The top four etiologies of hydrocephalus included post-cranial surgery (23.3%), brain tumor or cyst (22.9%), normal pressure hydrocephalus (15%), and intracranial hemorrhage (13.7%). The overall incidence of shunt malfunction was 15.4% with the median time to first shunt failure being 120 days. Etiology of hydrocephalus (P = 0.030) had a significant association with the development of shunt malfunction. Early shunt failure was associated with age (P \u3c 0.001), duration of hospital stay (P \u3c 0.001), Glasgow Coma Scale (GCS) score less than 13 (P = 0.010), excision of brain tumors (P = 0.008), and placement of extra-ventricular drains (P = 0.033).Conclusions: Patients with increased age, prolonged hospital stay, GCS score of less than 13, extra-ventricular drains in situ, or excision of brain tumors were more likely to experience early shunt malfunction

CORPORATE GOVERNANCE AND EARNINGS MANAGEMENT: THE ROLE OF THE BOARD OF DIRECTOR

This study investigates the association between earnings management and corporate governance characteristics in the Chinese context. Chinese corporate governance system is improved in past two decades after deciding to move away from planned economy to market-oriented one. The data is collected from the Chinese A-listed firms for the period of 2008 to 2016 to investigate the impact of Board characteristics on Earnings management. Additionally, this study demonstrates if earnings management is still an issue in the Non-SOE or not?. This study finds that board size mitigates the earnings management, and board independence is not playing there due role in monitoring the top management. The board meetings are not so effective and therefore not contributing to mitigating the earnings management. CEO duality is not a big issue just like in developed countries. Furthermore, When segrgating the sample on the basis of ownership type, we find that, a board meeting is affective in SOE as compare to Non-SOE.Furthermore, board size substitutes the weak external governance mechanism and constrains Earnings management. Board meeting plays a complementary effect when external governance mechanism is strong. The findings of this study are significant for all stakeholders to analyze and to improve the board effectiveness and the financial reporting quality before making any decision

CORPORATE GOVERNANCE AND EARNINGS MANAGEMENT: THE ROLE OF THE BOARD OF DIRECTOR

This study investigates the association between earnings management and corporate governance characteristics in the Chinese context. Chinese corporate governance system is improved in past two decades after deciding to move away from planned economy to market-oriented one. The data is collected from the Chinese A-listed firms for the period of 2008 to 2016 to investigate the impact of Board characteristics on Earnings management. Additionally, this study demonstrates if earnings management is still an issue in the Non-SOE or not?. This study finds that board size mitigates the earnings management, and board independence is not playing there due role in monitoring the top management. The board meetings are not so effective and therefore not contributing to mitigating the earnings management. CEO duality is not a big issue just like in developed countries. Furthermore, When segrgating the sample on the basis of ownership type, we find that, a board meeting is affective in SOE as compare to Non-SOE.Furthermore, board size substitutes the weak external governance mechanism and constrains Earnings management. Board meeting plays a complementary effect when external governance mechanism is strong. The findings of this study are significant for all stakeholders to analyze and to improve the board effectiveness and the financial reporting quality before making any decision

Impact of Different Potassium (K) Application on Seed Protein Content of Brassica under Different Levels of Irrigation in Field Condition

Pakistan is confronting a chronic scarcity of domestic edible oil requirements. One of the major issues with brassica oil seed production is the water requirement of the brassica crop. Field experiments were laid out in randomized complete block design (RCBD) with split plot arrangements at Malakandher Research Farm Khyber Pakhtunkhwa Agricultural University Peshawar Pakistan to study the effect of different levels of irrigation and potassium on seed protein content of Brassica. Four varieties Wester, Rainbow, Oscar and Legend were selected on the basis of their good response to potassium application in water stress conditions. The data revealed that maximum seed protein content (21.98%) was observed in those treatments where 100% irrigation level was applied and minimum seed protein content (19.37%) was produced by plants where 60% irrigation level was applied. Maximum seed protein content (21%) was in plants treated with 120 kg K ha-1 and minimum seed protein content (20.14%) with 60 kg K ha-1. The interaction between I x K showed maximum seed protein content (22.43%) in those plants treated with 100% irrigation level and 120 kg K ha-1 and minimum seed protein content (19.14%) was observed with 60 kg K ha-1 and 60% irrigation level. Maximum seed protein content (22.77%) was produced by variety Wester (V1) at 100% irrigation level and 120 kg K ha-1 while minimum seed protein content (18.80%) was given by variety Oscar (V3) when treated with 60 kg K ha-1 and 60% irrigation level. Keywords: Brassica, Oil Seed, Seed Protein, Variety, Irrigation, Potassium

Influence of Different Potassium (K) Application On Seed Glucosinolate Content Of Brassica Under Stress Condition In The Field

Field experiments were laid out in randomized complete block design (RCBD) with split plot arrangements at Malakandher Research Farm Khyber Pakhtunkhwa Agricultural University Peshawar Pakistan to study the effect of different levels of irrigation and potassium on seed protein content of Brassica. Four varieties Wester, Rainbow, Oscar and Legend were selected on the basis of their good response to potassium application in water stress conditions. maximum GSL content (49.2 ?mol g-1) was observed in treatments of 100% irrigation while minimum GSL content (16.4 ?mol g-1) was produced by plants where 60% irrigation was applied. potassium showed maximum GSL content (34.7 ?mol g-1) with 60 kg K ha-1 and minimum GSL content (31.0 ?mol g-1) was observed in treatments with 120 K kg ha-1. The data shown in appendix A29 suggested that maximum GSL content (40.7 ?mol g-1) was produced by variety Wester (V1) when applied with 60 kg K ha-1 and minimum GSL content (25.7 ?mol g-1) was given by variety Legend (V4) when treated with 120 kg K ha-. case of interaction between I x K, maximum GSL content (50.7 ?mol g-1) was noted in plants treated with 60 kg K ha-1 and 100% irrigation level while minimum GSL content (14.1 ?mol g-1 ) with 120 kg K ha-1 and 60% irrigation level. Further, the data given in appendix A29 indicated that maximum GSL content (56.5 ?mol g-1) was produced by variety Wester (V1) when treated with 100% irrigation level and 60 kg K ha-1 while minimum GSL content (8.9 ?mol g-1) was also given by variety Wester (V1) at 120 kg K ha-1 and 60% irrigation level.Keywords. Glucosinolate, Potassium, Irrigation, Variety, Treatmen

Seasonal Variations in Soil Conditions, Its Classification and Mapping of Dry Sub Tropical Region of Uthal, District Lasbela

The study on soil classification and seasonal variation was carried out during 2011-12 in Tehsil Uthal, District Lasbella (Balochistan). The water and soil samples were collected and subjected to determine for various physico-chemical properties and accordingly the results were formulated and compared with standard values. In winter soil EC in Zone 1, Zone 2, Zone 3 and Zone 4 area was 2.218, 1.99, 2.43 and 1.22 dS m-1,pH value 8.1, 8.3, 8.3 and 7.8, HCO3- 2.0125, 1.725, 1.675 and 2.5875 meq L-1, Na2+ 13, 12, 11.4125 and 14meq L-1 ,Ca2+ 7, 6, 6 and 7meq L-1 while the TDS in soil samples were 1571, 1638, 1902 and 837, respectively. In summer soil EC in Zone 1, Zone 2, Zone 3 and Zone 4area zones was 2.27, 2.04, 2.66 and 1.29 dS cm-1, pH value 8.7, 8.4, 8.4 and 8.0, HCO3-1.7375, 1.675, 1.5375 and 1.85meq L-1, Na2+ 13, 13, 12 and 16meq L-1,Ca2+6, 6, 6 and 7meq L-1 while the TDS in soil samples were 1605, 1713, 1001 and 952, respectively. Average value of ECe of 2.04 dSm-1.  The ECe values ranged 1.08 to 3 dSm-1. The average values of ECe at the given depth verify that marginal salinity was present in the soil. This may be due to the leaching of salts to the deeper layers. The average value of SAR is 9.18. The SAR ranged from 6.8 to 12.2. The ratios are less than 13 which show that concentration of Na+ ions to that of Ca+2 and Mg+2 is low. The average value of SAR is 9.18. The SAR ranged from 6.8 to 12.2. The ratios are less than 13 which show that concentration of Na+ ions to that of Ca+2 and Mg+2 is low. This shows improvement in soil. Keywords: Soil, Electrical Conductivity, SAR, Summer, Winter, Zones, Mappin

Factors affecting functional outcome after decompressive craniectomy performed for traumatic brain injury: A retrospective, cross-sectional study

Background: Factors affecting functional outcome after decompressive craniectomy (DC) performed for traumatic brain injury (TBI) remain poorly understood.Methods: We conducted a retrospective study of all patients who underwent primary DC for TBI at our hospital between 2010 and 2014. Multivariate regression analyses were used to determine the predictors of functional outcome and overall survival.Results: A total of 98 patients with severe (n = 81, 82.6%) or moderate (n = 17, 17.4%) TBI underwent primary DC and were included in this study. The 30-day and overall mortality rates were 15.3% and 25.5%, respectively. At a median follow-up of 90 (interquartile range (IQR): 38-180) days, median Karnofsky Performance Status (KPS) and Glasgow outcome scale-extended (GOSE) scores were 50 (IQR: 20-70) and 5 (IQR: 3-7), respectively. Young age and severe TBI were predictors of mortality. Glasgow coma scale (GCS) score on discharge was a strong predictor of KPS and GOSE scores.Conclusion: Primary DC afforded an acceptable functional outcome (GOSE score ≥5) in 45.9% of patients. Young age and lower GCS at presentation were associated with worse survival. GCS score on discharge was a strong predictor of functional outcome

ARE PULP SENSIBILITY TESTS STILL SENSIBLE?

Background: Electric and thermal tests are the most commonly employed methods for the diagnosis of pulp health status. The objectives of our study are to assess the validity, yield and accuracy of cold and electric pulp tests in determining pulp vitality of teeth requiring endodontic treatment. Methods: A cross sectional study was carried out at the Dental Clinic of Aga Khan University Hospital on 75 patients requiring endodontic treatment. Before commencement of endodontic treatment, a provisional diagnosis of pulp status was made using an electric pulp tester and cold test. The tooth was then labelled as either vital or necrotic. Then an access openings was made and tooth’s actual pulp status (vital/necrotic) was determined by observing bleeding in the pulp chamber. The validity, yield and accuracy were calculated on the basis of these findings. Results: The sensitivity, specificity, positive predictive value and negative predictive value and accuracy of cold test were 84%, 88%, 93%, 73% respectively. The sensitivity & specificity of electric test were 82% and 88% respectively whereas the positive predictive value, negative predictive value and accuracy of electric test were 93% and 71% respectively. The accuracy of cold and electric pulp test were 85% and 84% respectively. Conclusion: Both cold test and EPT have similar sensitivity, specificity and accuracy values. Although vitality tests have a promising future in diagnosis of pulp health status but within limitation of this study we found that sensibility tests have satisfactory validity and accuracy values to be used routinely prior to endodontic and restorative treatments especially when used in conjunction with one each other