Efficiency of the foreign exchange markets in South Asian Countries

This paper examines the weak form efficiency of the foreign exchange markets in seven SAARC countries using monthly return series for each of these markets over a period of 21 years (1985-2005). We applied a battery of unit root tests and variance ratio tests (individual and multiple) to see whether the return series (and also, the raw data) follow random walk process. Our results suggest that the increments of the return series are not serially correlated. Therefore, we conclude that foreign exchange markets in SAARC countries are weak form efficient.

Two Essays in Empirical Asset Pricing

The dissertation consists of two essays. The first essay investigates the ability of prior returns, relative to some aggregate market returns, to predict future returns on industry style portfolios. By pooling time series of returns across industries for the period between July 1969 and June 2012, we find that prior returns differential predicts one month ahead returns negatively, even in the presence of a set of popular state variables. The predictability remains significant and negative for up to 5 month ahead returns. The predictability is shown to be robust to alternative specifications, estimation methodology and industry classifications. A possible explanation of this finding is based on time–varying (dynamic) loss aversion among investors. More specifically, when combined with house money effects, prior performance has inverse relationship with degree of loss aversion leading to predictability in the next period returns. The second essay examines the nature of time variation in the risk exposure of country mutual funds to the US market movement and to the benchmark foreign market movement. It uses weekly data on 15 closed end funds and 19 exchange traded funds for the sample period between January, 2001 and December, 2012. Conditional factor models are employed to uncover the time variation in the estimated betas through short horizon regressions. The findings of the paper indicate considerable time variation in risk exposure of country mutual funds to the US market and foreign market risk factors. Additional investigation reveals the following observations. First, the US market betas suffer greater variation over the sample period than the target foreign market betas. Second, the overall fluctuation in betas for the closed end funds is found to be higher than that for the exchange traded funds. Third, emerging market funds experience more oscillation in the risk exposure than their developed market counterparts. It is found that a combination of the US macroeconomic state variables and investors’ sentiment can predict future betas significantly. The findings of the paper have important implication for US investors seeking diversification benefits from country mutual funds

A robust scheme to defend against disassociation and deauthentication DoS attacks in WLAN networks

Wireless 802.11 (also known as WLAN) has many flaws that expose the medium to numerous types of attacks. WLAN control frame consists of three major parts; data, management and control frames. Data frame is whereby data carried on, in the meantime, management and control frames are both responsible for maintaining the communication between the clients and the access point. The absence of encryption at both of these two frames exposes the medium to inevitable various types of DoS attacks at Data Link Layer. The attacker might spoof the unencrypted Deauthentication/Disassociation message together with the MAC address of the targeted access point and keep retransmitting it to all clients causing a continuous disconnection in WLAN networks. Wireless 802.11w standards has succeeded mitigating the flaw by encrypting the frames, yet only when WPA2 encryption is enforced. In this paper, we developed an enhanced proposed WLAN scheme to mitigate Deauthentication and Disassociation DoS attacks on WLAN networks. The proposed scheme is based on modifying the last twenty bits of the management frame in 802.11n standard using an enhanced version of Linear Congruential Algorithm called MAX algorithm. This is to provide a layer of authentication with no need to enforce WPA2 encryption. The proposed scheme is evaluated using CommeView Simulator and showed to be robust by slowing the attacks in an average of 3551 second on both encrypted and unencrypted networks

On some imbedding relations between certain sequence spaces

In the present paper, we introduce the sequence space ` lλp of non-absolute type which is a p-normed space and a BK-space in the cases of 0 < p < 1 and 1 ≤ p < ∞, respectively. Further, we derive some imbedding relations and construct the basis for the space lλp, where 1 ≤ p < ∞. Remove selectedВведено поняття простору послiдовностей lλp неабсолютного типу, який є p-нормованим простором i BK-простором у випадках 0 < p < 1 i 1 ≤ p < ∞ вiдповiдно. Крiм того, отримано деякi спiввiдношення вкладення та побудовано базис для простору lλp, де 1 ≤ p < ∞

Clinical profile and risk factors associated in patients of mucormycosis in COVID-19 pandemic: a study in a tertiary centre

Background: The objective of this study was to determine the clinical profile and risk factors associated in patients of mucormycosis in COVID-19 pandemic.Methods: It was a prospective observational study conducted at a tertiary care centre in the month of May and June 2021. It involved all patients of mucormycosis mainly involving paranasal sinuses and orbit. The clinical profile and associated risk factors leading to mucormycosis were studied.Results: Thirty patients of mucormycosis mean age 56.62 years out of them 25 (83.33%) male and 5 (16.66%) female were studied. Twenty-four patients (80%) had COVID-19 infection, out of them 7 (29.2%) were active and 17 (70.8%) had recovered within 4 weeks. Five (16.6%) patients were suspected as they had symptoms of COVID-19 previously   but never got tested. One   patient had no history of COVID infection. All the patients were diabetic at the time of presentation, out of them 26 (86.6%) of patients were known diabetic and 4 (13.3%) became diabetic after COVID-19 infection. The ethmoids were the most common sinuses affected. Intra-orbital extension was seen in 13 (43.3%) of cases   while intracranial extension was seen in 4 (13.3%) patients. Twenty-eight (93.3%) patients gave history of steroids intake. Antibiotics were taken by 76.6% patients while zinc supplement was used by 83.3% patients. Oxygen was used 10 (33.3%) patients, 80% of them using face mask or canula and 4 of them requiring mechanical ventilatory support.  Conclusions: The risk factors associated with mucormycosis in COVID pandemic must be given serious consideration as there is sudden increase in the case and mortality is very high. Uncontrolled diabetes and over use of steroids in COVID management are two main aggravating factors, however other factors must also be studied thoroughly

Stakeholders' response to the private sector participation of water supply utility in Karachi, Pakistan

Changes are proposed to improve urban water supply systems around the globe. Improvement in service delivery mechanisms, institutional efficiency, financial viability and acceptance by users are the key criteria for initiating and sustaining a change. To improve the situation of water supply in Karachi, Pakistan, advised by the World Bank, a private sector participation (PSP) strategy was formed during the 1990s. The strategy aimed to promote a gradual increase of PSP in water and sanitation services. The proposed project faced strong resistance from stakeholders, mainly civil society, leading to its suspension. Efforts are being made to revive the PSP and to make it acceptable to the stakeholders concerned. The paper documents and analyses the stakeholders’ response to the anticipated PSP process and the possible social and economic impacts. The study makes a contribution in the areas of participation and consensus building in the context of PSP. Willingness to negotiate continuously and even consideration of possible alternatives based on the changing situations are the key to any way forward for sustainable improvements

Rampant food adulteration in Bangladesh: Gross violations of fundamental human rights with impunity

Food adulteration in Bangladesh is rampant and an increasingly serious concern for its residents. Several studies including those of the Directorate General of Health Services reveal that hundreds of people are getting killed every year eating adulterated foodstuffs and no one seems to have any real concern about such a life-threatening wrongful act. Food adulteration is criminally prohibited, but the wrongdoers care little about this proscription simply because of the continued apathy of the governmental agencies concerned and implicit acceptance or insensible ignorance of consumers. However, the current fragmented legal and regulatory regime for food safety in Bangladesh falls short of international standards. This article demonstrates that the Government of Bangladesh is obliged to prevent food adulteration and to punish perpetrators under its international as well as constitutional obligations. It is also submitted that effective regulation of such an endemic malfeasance entails weakening the offenders by adopting international standards and educating the consumers at the same time

Investigating the Correlation Between Presence and Reaction Time in Mixed Reality

Measuring presence is critical to improving user involvement and performance in Mixed Reality (MR). \emph{Presence}, a crucial aspect of MR, is traditionally gauged using subjective questionnaires, leading to a lack of time-varying responses and susceptibility to user bias. Inspired by the existing literature on the relationship between presence and human performance, the proposed methodology systematically measures a user's reaction time to a visual stimulus as they interact within a manipulated MR environment. We explore the user reaction time as a quantity that can be easily measured using the systemic tools available in modern MR devices. We conducted an exploratory study (N=40) with two experiments designed to alter the users' sense of presence by manipulating \emph{place illusion} and \emph{plausibility illusion}. We found a significant correlation between presence scores and reaction times with a correlation coefficient -0.65, suggesting that users with a higher sense of presence responded more swiftly to stimuli. We develop a model that estimates a user's presence level using the reaction time values with high accuracy of up to 80\%. While our study suggests that reaction time can be used as a measure of presence, further investigation is needed to improve the accuracy of the model