Simulated rotor test apparatus dynamic characteristics in the 80- by 120-foot wind tunnel

A shake test was conducted in the 80 by 120 foot Wind Tunnel at NASA Ames Research Center, using a load frame and dummy weights to simulate the weight of the NASA Rotor Test Apparatus. The simulated hub was excited with broadband random excitation, and accelerometer responses were measured at various locations. The transfer functions (acceleration per unit excitation force as a function of frequency) for each of the accelerometer responses were computed, and the data were analyzed using modal analysis to estimate the model parameters

Pricing European currency options with high-frequency data

Technological innovation has changed the financial market significantly with the increasing application of high-frequency data in research and practice. This study examines the performance of intraday implied volatility (IV) in estimating currency options prices. Options quotations at a different trading time, such as the opening period, midday period and closing period of a trading day with one-month, two months’ and three months’ maturity, are employed to compute intraday IV for pricing currency options. We use the Mincer–Zarnowitz regression test to analyse the volatility forecast power of IV for three different forecast horizons (within a week, one week and one month). Intraday IV’s capability in estimating currency options price is measured by the mean squared error, mean absolute error and mean absolute percentage error measure. The empirical findings show that intraday IV is the key to accurately forecasting volatility and estimating currency options prices precisely. Moreover, IV at the closing period of the beginning of the week contains crucial information for options price estimation. Furthermore, the shorter maturity intraday IV is suitable for pricing options for a shorter horizon. In comparison, the intraday IV based on the longer maturity options subsumes appropriate information to price options with higher accuracy for the longer horizon. Our paper proposes a new approach to accurately pricing currency options using high-frequency data

An open innovation intraday implied volatility for pricing Australian dollar options

This study introduces the intraday implied volatility (IV) for pricing the Australian dollar (AUD) options. The IV is estimated using the at-the-money one-month, two-month, and three-month maturity AUD options traded in the opening, midday, and closing period of a trading day. The Mincer-Zarnowitz regression test evaluates the predictive power of IV to forecast the foreign exchange volatility for the within-week, one-week, and one-month horizon. The mean absolute error, mean squared error, and root mean squared error measures are employed to assess the performance of IV in estimating the price of currency options for the within-week, one-week, and one-month horizon. This study reveals four critical findings. First, a three-month maturity IV does not contain vital information for pricing options. Second, IV incorporated information is not relevant to compute the value of options for a horizon of less than a week. Third, IV in the closing period of Monday or Tuesday subsumes most of the essential information to estimate options price. Fourth, the shorter (longer) maturity IV provides critical information to price options for the shorter (longer) horizon. The intraday IV is a new dimension of unobservable volatility in accurately pricing currency options for researchers and practitioners

Awareness and practices of contraceptive use among university students in Botswana

In Botswana, unplanned pregnancies, especially among the youth constitutes a growing health and social problem. Research in the field of contraceptive practices, and the causes of sexual practices in Botswana, remains scarce and relatively limited. The objectives of this study was to investigate the awareness and utilization of various contraceptive methods, among university students in Botswana. A descriptive, cross-sectional, research study was conducted among 346 randomly selected students, who completed confidential, self-administered questionnaires. The average age of the respondents was 21 years (SD ¼ 2.8 years). The level of awareness among students regarding contraception was good (score ≥9). Both the male and the female students had almost similar awareness level of contraceptive use, as their mean scores were 8.79 and 8.72, respectively (p ¼ .733). All the female students (100%) were ‘aware’ that the effectiveness of the contraceptives used, as compared to male students, being 93.7%. A greater proportion of the female students (90.6%) knew that using contraceptives irregularly would result in pregnancy, in contrast to 76.4% males. More than half (59.0%) of the students indicated that they had engaged in sexual acts. Significantly, more male students (68.5%) had sexual experiences prior to the study, compared to 54.5% of their female counterparts (p ¼ .038).The majority of the students (76%) reported that they had always used contraceptive methods. The most  commonly used contraceptive method was the condom (95.6%), followed by oral contraceptive pill (86.7%). There was no significant association found between the level of awareness and the use of contraceptives. Results suggested that many students still engaged in risky, contraceptive practices by engaging in unprotected sexual acts. Therefore, there is a need to educate the students about sexually transmitted infections, the different contraceptive methods and the regular use of the available contraceptives.Keywords: awareness, utilization, contraception, university students, Botswan

Improving and sustaining quality of child health care through IMCI training and supervision: experience from rural Bangladesh

CAUL read and publish agreementfals

Video-Based Analyses of Parkinson's Disease Severity: A Brief Review

Remote and objective assessment of the motor symptoms of Parkinson's disease is an area of great interest particularly since the COVID-19 crisis emerged. In this paper, we focus on a) the challenges of assessing motor severity via videos and b) the use of emerging video-based Artificial Intelligence (AI)/Machine Learning techniques to quantitate human movement and its potential utility in assessing motor severity in patients with Parkinson's disease. While we conclude that video-based assessment may be an accessible and useful way of monitoring motor severity of Parkinson's disease, the potential of video-based AI to diagnose and quantify disease severity in the clinical context is dependent on research with large, diverse samples, and further validation using carefully considered performance standards

Effect of hydrogen sulphide on liver somatic index and Fulton's condition factor in Mystus nemurus

The growth rate and liver somatic index were significantly (P0.05) in Fulton's condition factor were detected between the exposed fish and the controls. The results revealed that liver somatic index is a more sensitive indicator of hydrogen sulphide toxicity compared to Fulton's condition factor

Pharmacological investigation of selected medicinal plants of Bangladesh

Purpose: To pharmacologically investigate the methanol and petroleum ether extracts of the plant leaves of Manilkara zapota (MZME and MZPE, respectively), Abroma augusta (AAME and AAPE, respectively) and Vitex negundo (VNME and VNPE, respectively).Methods: Analgesic and anti-diarrheal activities were assessed by acetic acid-induced writhing and castor oil-induced diarrhea in mice, respectively, while CNS depressant activity was evaluated using hole-cross and open-field method by observing the decrease in exploratory behavior and spontaneous motor activity in mice, respectively.Results: All the extracts exhibited good analgesic activity at a dose of 200 mg/kg with the following rank order of activity: MZME > MZPE > VNME > VNPE > AAME > AAPE. Analgesic activity was insignificant at 100 mg/kg dose except for VNPE (67.81 % inhibition). The extracts produced significant reduction in diarrheal episodes in mice at a dose of 400 mg/kg MZPE (highest protection: 80.3 %, p < 0.05) and VNME (lowest protection: 38.6 %, p < 0.001). The extracts demonstrated CNS depressant activity in a dose-dependent manner (p < 0.05 compared to the standard except for AAME and AAPE which showed insignificant activity).Conclusion: The results indicate that the traditional use of the investigated plants appears to be justified; however, further studies are required to unravel the underlying mechanisms of action.Keywords: Manilkara zapota, Abroma augusta, Vitex negundo, Analgesic, Central nervous system depressant, Anti-diarrhoea

Can mangroves help combat sea level rise through sediment accretion and accumulation?

Mangroves have substantial roles to induce sedimentation in the vulnerable coastal regions, which subsequently helps to combat climate change induced impacts like sea level rise. Although Sarawak has numerous pristine estuarine mangroves, studies on the roles of these mangroves in regards to sediment deposition are scanty. Therefore, this study was carried out to determine the sediment accretion and accumulation pattern of pristine Sibuti mangrove using tiles and sediment traps from January to December 2013. Monthly average accretion and accumulation rate of sediments of this mangrove were 0.55 mm and 0.08 g cm-2, respectively. A total of 6.56 mm and 0.93 g cm-2 sediments were accreted and accumulated annually. Significantly positive correlation (r=0.794) was found for the monthly accretion of sediments with accumulation. Accretion and accumulation of sediments were also positively correlated with rainfall. Comparatively higher rate of accretion and accumulation of sediments were estimated in the months of wet season when the rainfall and tidal inundation duration were high. Erosion was found higher in the months of dry season when the rainfall was low. Seasonal variations were not found for sediment accretion as well as accumulation in the study area. The findings of the study suggest that the roles of this forest in regards to sediment accretion through retention is compatible with the predicted annual rate of sea level rise of 1.8 to 5.9 mm within 21st century by IPCC