Economic Evaluation of Placer Gold Along River Indus From Ghazi to Kund, Khyber Pakhtunkhwa, Pakistan: Implications for Commercial Scale Pilot Plant

A detailed study was conducted on Indus river in order to evaluate the economic potential. Samples werecollected for geochemical studies from both stream sediments (SS) and heavy mineral concentrates (HMC) along Indusriver from Ghazi, Hund, Beka, Alladher and Kund in Khyber Pakhtunkhwa province. All the samples were analyzed forgold (Au), silver (Ag) and base metals in order to get information about geochemical associations. Panning and sluicemethods were applied for the collection of these samples and extraction of visible gold. Results show that HMC havehigh Au contents, having maximum value of 44.15 g/t and 39.15 g/t in Kund and Beka areas respectively with anaverage value of 15.18 g/ton and 11.37 g/ton while the SS have average amount of Au as 0.8 g/t. In both these mediahigher concentration of gold was found in HMC. On the basis of results from both sampling media, the placer golddeposits in Kund, Alladher and Beka are considered highly economical for the commercial exploration of placer gold.Overall, the HMC derived from silt, sand, gravels and cobbles along Indus river indicated potential for placer gold thatcan be utilized for extraction of gold at commercial scale

A cost effective preparative thin layer chromatography cleanup method for high performance liquid chromatography analysis of aflatoxins B1, B2 and G2

Aflatoxins are the by-products of fungal metabolism and common contaminants in feed. To keep their level below permissible limits, various assays have been developed. Currently, High Performance Liquid Chromatography (HPLC) with fluorescence detection of toxins is most widely used method but the cleanup methods requiring specific gadgets have increased the cost of the assay. Thin Layer Chromatography (TLC) is effective and economical but it only gives semi quantitative determination for aflatoxin.This study explores the preparative potential of TLC as cleanup method for HPLC analysis of toxin. Standard aflatoxins solutions containing 10 ng of B1, 2.5 ng of B2 and 2.5 ng of G2 were spotted on silica plates and then extracted using chloroform and acetone (4:1). The extracted toxins were resolved and quantified on HPLC using fluorescent detection. The results showed 81, 79 and 60% mean recovery of aflatoxin B1, B2 and G2, respectively. This method was proved equivocally comparable to other methods of aflatoxins cleanup and thus can be used as an alternative cost effective cleanup method

IMPACT OF MACROECONOMIC VARIABLES ON FINANCIAL PERFORMANCE: EVIDENCE OF AUTOMOBILE ASSEMBLING SECTOR OF PAKISTAN STOCK EXCHANGE

The study examines the macroeconomic variables impact on financial performance, using the financial statement of listed companies in Automobile sector of Pakistan stock exchange. The study covered the period from 2007 to 2016. Before applying the GMM model the preliminary test was done. Firm performance is measured with three ratios i.e., return on assets (ROA), return on equity (ROE) and gross profit margin ratio (GPM). The results revealed that the selected macroeconomics variables have the negative relationship with return on equity, return on assets and gross profit margin and the inflation has positive relation with return on equity and negative relation with return on assets (ROA) and gross profit margin (GPM)

Examining the contribution of fiscal policy on economic growth: Analytical insights from Pakistan

To better understand the influence of fiscal policy (FP) on economic growth (EG) in Pakistan, this study investigates the importance of the amount of output produced by different factors of production in Pakistan's economy. The annual time series data has been collected from the State Bank of Pakistan and World Bank Data-Base from the years (2001-2020). The Autoregressive Distributed Lag (ARDL) model is used for empirical research to assess the significant factors of EG, and the Augmented Dickey-Fuller (ADF) unit root test is used to ensure that all of the variables are stationary. Using annual time series data from 2001 to 2020. Based on these findings, this study recommends adopting a proactive fiscal policy framework that incorporates expansionary measures. We argue that this strategy has the capacity to stimulate and maintain Pakistan's economic growth path, thereby fostering a more promising and prosperous future. Moreover, the study found the impact of government expenditures (GE), gross fixed capital creation (GFCC), and direct and indirect taxes on Gross domestic Product (GDP). Additionally, findings showed that government expenditures, gross fixed capital creation, indirect, and direct taxes have a strong effect on economic growth. It is argued that an expansionary fiscal policy in the future could greatly benefit Pakistan's economic growth

Gastroprotective potential and mechanisms of action of Hedera nepalensis

Hedera nepalensis (H. nepalensis) , belonging to the family Araliaceae, is a medicinal plant traditionally used to treat stomach problems. The current study investigated the gastroprotective potential and the mechanism of action of H. nepalensis in diclofenac-and ethanol-induced ulcer models. Anti-oxidant and lipid peroxidation inhibitory prospects of H. nepalensis were checked out by free radical scavenging assay and UV spectrophotometer respectively. Effect of H. nepalensis on the pH, gastric total acidity of gastric juice and protective effects of H. nepalensis against ulcer models have been examined. Histopathological studies have been carried out. The aqueous methanol extract of H. nepalensis (100 µg/mL) showed anti-oxidant (83.55%) and lipid peroxidation inhibitory (70.88%) potential at 1000 µg/mL; the extract had no buffer potential. The extract (400 mg/kg) significantly (81.12% and 63.46%) showed gastroprotective effect in diclofenac and ethanol-induced rat ulcer models respectively. Histopathological studies confirmed the biochemical findings. FTIR analysis showed the presence of carboxylic acid, alkanes, conjugated alkanes, aldehydes and alkyl-aryl ethers. Gallic acid, M-coumaric acid and quercetin were found by HPLC analysis. H. nepalensis exhibited significant protection against diclofenac and ethanol induced gastric damage by anti-oxidant and lipid peroxidation suppression effects suggesting potential broad utility in treatment of diseases characterized with gastric damage

IMPACT OF MACROECONOMIC VARIABLES ON FINANCIAL PERFORMANCE: EVIDENCE OF AUTOMOBILE ASSEMBLING SECTOR OF PAKISTAN STOCK EXCHANGE

The study examines the macroeconomic variables impact on financial performance, using the financial statement of listed companies in Automobile sector of Pakistan stock exchange. The study covered the period from 2007 to 2016. Before applying the GMM model the preliminary test was done. Firm performance is measured with three ratios i.e., return on assets (ROA), return on equity (ROE) and gross profit margin ratio (GPM). The results revealed that the selected macroeconomics variables have the negative relationship with return on equity, return on assets and gross profit margin and the inflation has positive relation with return on equity and negative relation with return on assets (ROA) and gross profit margin (GPM)

Internal Model Control (IMC)-Based Active and Reactive Power Control of Brushless Double-Fed Induction Generator with Notch Filter

The increase in demand for electricity and, in particular, green energy has put renewable energy systems at the focal point of energy policy worldwide. The higher reliability of brushless doubly fed induction generators (BDFIGs) makes them suitable for offshore and remote wind energy generation (WEG) applications. Besides, controlling the active and reactive powers in an electrical power system is critical for optimal voltage regulation, reduced power losses, and enhanced utilization of installed equipment. However, the existing literature on BDFIG’s active and reactive power control highlights the poor dynamic response and high transients with harmonic generation during inductive load insertion. It is because the Ziegler technique was employed to select PI gains, and the instantaneous reactive power theory was used to mitigate harmonics. Considering that, this paper proposes a vector control (VC) method for BDFIGs in wind turbines, in which the proportional-integral (PI) gains for internal model control (IMC) are optimized to improve the dynamic response of the active and reactive power during inductive load insertion. The proposed method reduces the complexity, time consumption, and uncertainty in making the optimal choice. In addition, to reduce a double fundamental frequency component to the point-of-common-coupling (PCC) voltage, the excellent characteristics of the notch filter are utilized in the grid-side converter (GSC)-based vector control scheme. The simulation results in MATLAB/ Simulink show that the proposed IMC-based vector control scheme with a notch filter provides satisfactory results with a minimum peak value compared to existing techniques