Multi-scale Lead-Lag Relationship between the Stock and Futures Markets: Malaysia as a Case Study

There is a considerable literature relating to a lead-lag relationship between the stock index (spot) and stock index futures markets in developed countries compared to emerging countries. The analysis of this relationship in an emerging market based on a different investment horizon is significant for both academic and trading purposes. In this study, we analyze the lead-lag relationship between stock index and stock index futures in Malaysia. We use a new approach based on the Continuous Wavelet Transform (CWT) and the Discrete Wavelet Transform (DWT). The results show variability of the lead-lag relationship across frequency ranges and time scales, and also occasional in-phase behaviour between both markets. The relationships between stock index and stock index futures are shown to evolve over time with non-homogeneous trends across different time scales. Some strong correlations have been found in lead-lag interactions between the markets. The result from this study would provide a better picture of a current derivatives market in emerging countries, specifically in Malaysia. Hopefully it will shed some light in furthering the development of Islamic equity futures within the Islamic capital market, therefore will encourage Islamic asset managers to use derivatives as a hedging tool to protect their funds’ value

Multi-scale Lead-Lag Relationship between the Stock and Futures Markets: Malaysia as a Case Study

There is a considerable literature relating to a lead-lag relationship between the stock index (spot) and stock index futures markets in developed countries compared to emerging countries. The analysis of this relationship in an emerging market based on a different investment horizon is significant for both academic and trading purposes. In this study, we analyze the lead-lag relationship between stock index and stock index futures in Malaysia. We use a new approach based on the Continuous Wavelet Transform (CWT) and the Discrete Wavelet Transform (DWT). The results show variability of the lead-lag relationship across frequency ranges and time scales, and also occasional in-phase behaviour between both markets. The relationships between stock index and stock index futures are shown to evolve over time with non-homogeneous trends across different time scales. Some strong correlations have been found in lead-lag interactions between the markets. The result from this study would provide a better picture of a current derivatives market in emerging countries, specifically in Malaysia. Hopefully it will shed some light in furthering the development of Islamic equity futures within the Islamic capital market, therefore will encourage Islamic asset managers to use derivatives as a hedging tool to protect their funds’ value

Prevalence of Plasmodium species in patients attending in Ed-Babiker health center in Khartoum State, Sudan.

Background: Malaria is a serious vector-borne tropical disease that remains one of the primary reasons for death in several developing countries. In Sudan, almost 75% of the population is at risk of developing malaria. Aim: To study the prevalence and diversity of Plasmodium species based on the data collected in a health center-based survey in Ed-Babiker Health Center-Sudan. Methods: This was cross-sectional malaria survey carried out in Ed-Babiker Health Center during the colder season from December 2020 to March2021.The survey was categorized according to gender and age groups.Results: The overall prevalence of Plasmodium species among malaria suspected cases was 33%.  P. falciparum was is the main infecting malaria species in Ed-Babiker Health Center as we found that about (24%) of cases were infected with that species. The prevalence showed significant variations between the localities (P value <0.001), which could be explained by differences in population movement, refugees' presence of and proximity to endemic neighboring states. Conclusion: Even though malaria in Ed-Babiker Health Center is still largely recognized to Plasmodium falciparum, P. vivax has been growing with worrying proportions and spreading to new areas. The emergence and marked increase of P. vivax poses new challenges to malaria treatment and control in Ed-Babiker Health Center.&nbsp

Retinal changes in visceral leishmaniasis by retinal photography

Background: In visceral leishmaniasis (VL), retinal changes have previously been noted but not described in detail and their clinical and pathological significance are unknown. A prospective observational study was undertaken in Mymensingh, Bangladesh aiming to describe in detail visible changes in the retina in unselected patients with VL. Methods: Patients underwent assessment of visual function, indirect and direct ophthalmoscopy and portable retinal photography. The photographs were assessed by masked observers including assessment for vessel tortuosity using a semi-automated system. Results: 30 patients with VL were enrolled, of whom 6 (20%) had abnormalities. These included 5 with focal retinal whitening, 2 with cotton wool spots, 2 with haemorrhages, as well as increased vessel tortuosity. Visual function was preserved. Conclusions: These changes suggest a previously unrecognized retinal vasculopathy. An inflammatory aetiology is plausible such as a subclinical retinal vasculitis, possibly with altered local microvascular autoregulation, and warrants further investigation. </p

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure

Arabic made easy/ Hashim

239 hal.; 21 cm

An Isolated Power Factor Corrected Cuk Converter with Integrated Magnetics for Brushless DC Ceiling Fan Applications

The usage of BLDC motors in the low-power range is increasing rapidly in home appliances such as ceiling fans. This has necessitated the development of reliable, compact and efficient AC-DC power supplies for motor drive circuitry. This paper presents a power supply design consisting of an AC-DC isolated PFC Cuk converter with integrated magnetics that supplies a single-shunt voltage source inverter for the sensorless drive of the BLDC fan motor. The proposed power supply design is comprised of an integrated magnetics structure in which the two inductors and the transformer windings share the same core. The zero input and output ripple current conditions have been derived from the reluctance model of the magnetic assembly. Smooth operation of the motor by minimizing the motor torque ripples is evident from the results. The Cuk converter operates in continuous conduction mode (CCM), employing the current multiplier method. The CCM-based current multiplier control loop ensures a near-unity power factor as well as low total harmonic distortion in the supply current. The current loop also provides over-current protection, enhancing reliability of the system. Moreover, the speed of the BLDC motor is controlled by the field oriented control (FOC) algorithm, which enables direct operation with alternate energy sources such as batteries and solar photovoltaic panels. The performance of the proposed supply is validated: motor torque ripple is reduced to only 2.14% while maintaining 0.999 power factor and only 4.72% THD at full load. Failure modes analysis has also been performed through software simulations, using the PLECS simulation environment. Due to the reliable power supply design with low ripples, it is well suited for low-power BLDC motors in home appliances and small power tools, in addition to ceiling fans