214 research outputs found
Intellectual property laws and Islam in Malaysia.
No full textPhDThis study is undertaken on the premise that Islam and Islamic law is to be taken into
serious consideration in any future legislative reform of laws in Malaysia. Islam being
the religion of the country and the strong religious sentiment of the Muslims (who
form the majority in Malaysia) cannot be overlooked or dismissed lightly by the
legislators in Malaysia. Reformation of intellectual property laws is timely, as we are
now approaching to the dateline set by GATF-Trips agreement which aim is to
improve our standard of intellectual property protection. This study seeks to analyze
and evaluate the current legislation pertaining to intellectual property in Malaysia in
terms of the philosophy and rules governing the existence, ownership and exercise of
these rights and their consistency and inconsistency with Islam and Islamic law. The
main objective of this study is to prove that a coherent and logical conceptual
framework of ownership of intellectual property can be derived from an Islamic
perspective which not only offers the basis of rights but also defines the scope of
these rights. From the point of ownership of rights, support can be obtained from the
normative framework of property rights within the traditional classification of 'mal'
(property) and 'haqq al-milkiyyah' (ownership rights) under Islamic law. From the
point of exercise of rights, the exact scope can be defined from the analysis of
fundamental concepts which have been developed by Muslim jurists. It has been
established that Islam and Islamic law offers a sound and systematic paradigm, which
in deeper analysis, can satisfy both our current obligations under international
treatises, as well as our responsibility to practise our religion to the fullest
Control characteristics of magnetotactic bacteria: Magnetospirillum magnetotacticum strain MS-1 and magnetospirillum magneticum strain AMB-1
Full text linkMagnetotactic bacteria have the potential to execute nontrivial tasks, such as microactuation, micromanipulation, and microassembly, under the influence of the controlled magnetic fields. Closed-loop control characteristics of these magnetic microorganisms depend on their self-propulsion forces (motility) and magnetic dipole moments. These properties can be controlled through the growth conditions of magnetotactic bacteria. We provide a comparison between two species of magnetotactic bacteria, i.e., Magnetospirillum magnetotacticum strain MS-1 and Magnetospirillum magneticum strain AMB-1. This comparison includes the characterization of their morphologies, magnetic dipole moments, and closed-loop control characteristics in the transient and steady states. The characterized average magnetic dipole moments of motile cells of M. magnetotacticum and M. magneticum strains are 1.4 × 10?16 A.m2 and 1.5 × 10?17 A.m2 at a magnetic field of 7.9 mT, respectively. These magnetic dipole moments are used in the realization of closed-loop control systems for each bacterial strain. The closed-loop control systems achieve point-to-point positioning of M. magnetotacticum cells at an average velocity of 32 ± 10 μm/s (approximately seven body lengths per second), and within an average region of convergence of 23 ± 10 μm (approximately four body lengths), while cells of M. magneticum strain are positioned at an average velocity of 30 ± 12 μm/s (approximately eight body lengths per second), and within an average region of convergence of 35 ± 14 μm (approximately 14 body lengths). These results suggest that the cells of M. magnetotacticum strain have a slightly greater tendency to provide desirable closed-loop control characteristics than cells of M. magneticum strain
Magnetic-based motion control of a helical robot using two synchronized rotating dipole fields
Full text linkThis work addresses the magnetic-based control of a helical robot and the mitigation of the magnetic forces on its dipole moment during radial steering using rotating permanent magnets. A magnetic system with two synchronized permanent magnets that rotate quasistatically is used to move the helical robot (length and diameter of 12.5 mm and 4 mm, respectively). We experimentally demonstrate that using two synchronized permanent magnets for radial steering of a helical robot achieves higher motion stability, as opposed to propulsion using single rotating dipole field. The two synchronized dipole fields decrease the lateral oscillation (average peak-to-peak amplitude) of the helical robot by 37%, compared to the radial steering using a single dipole field at angular velocity of 31 rad/s. We also show that driving the helical robot using two synchronized rotating magnets achieves average swimming speed of 2.1 mm/s, whereas the single rotating dipole field achieves average swimming speed of 0.4 mm/s at angular velocity of 31 rad/s for the rotating permanent magnets. The proposed configuration of the helical propulsion allows us to decrease the magnetic forces that could cause tissue damage or potential trauma for in vivo applications.</p
A RE-EXAMINATION OF THE ARCHITECTURE OF THE INTERNATIONAL ECONOMIC SYSTEM IN A GLOBAL SETTING: ISSUES AND PROPOSALS
Full text linkThe globalization of the world economy poses major challenges to the prevailing international economic system. The recent trade-investment system raises the issues of the marginalization of countries, firms, and agents if they are not capable to compete with large successful entities. The system engenders conflicts of interest in its interfacing with sovereign domains. In numerous cases such as employment and mutual trade benefits, it can produce zero sum outcomes. Consequently, significant segments of public opinion in many countries have mobilized against it. In the monetary and financial area, the system has from 1945 evolved on a piecemeal and ad hoc basis. In recent years, it has not been able to predict, prevent or effectively deal with financial crisis. It demonstrates a lacuna in global financial governance especially with respect to enforcing its rules on the major countries and bringing the private sector therein. The central institution, the IMF, is shown to be in need of basic reforms involving forging a global vision, reconsidering and updating conditionality, further democratization of political governance, and revamping the exchange rates and surveillance functions.
Development of a Coil Driver for Magnetic Manipulation Systems
Full text linkPulsewidth modulation (PWM) is the most commonly used technique to drive electromagnetic coils in magnetic manipulation systems. Relatively low PWM frequencies generate high-magnitude current ripple and magnetic field fluctuation. In this letter, coils are powered by a driver at PWM frequencies close to their self-resonant frequencies to generate high-frequency magnetic fields and minimize current ripple and magnetic field fluctuation. In order to protect the driver against the penetration of stray electromagnetic and magnetic fields, a multilayer shielding enclosure is employed. The coil driver is used to study the effect of varying PWM frequencies on current, magnetic field, and ohmic loss using Helmholtz, air, and iron core coils. The current ripple magnitude is significantly minimized when the coils are driven at PWM frequencies close to their self-resonant frequencies. This results in reduction of magnetic field fluctuation and provides more accurate measurement of magnetic field magnitude. Our experiments show that increasing the PWM frequency from 100 Hz to 25 kHz decreases the current ripple and magnetic fluctuation by two orders of magnitude, with a negligible effect on the ohmic loss.</p
Serial imaging of micro-agents and cancer cell spheroids in a microfluidic channel using multicolor fluorescence microscopy
Full text linkMulticolor fluorescence microscopy is a powerful technique to fully visualize many biological phenomena by acquiring images from different spectrum channels. This study expands the scope of multicolor fluorescence microscopy by serial imaging of polystyrene micro-beads as surrogates for drug carriers, cancer spheroids formed using HeLa cells, and microfluidic channels. Three fluorophores with different spectral characteristics are utilized to perform multicolor microscopy. According to the spectrum analysis of the fluorophores, a multicolor widefield fluorescence microscope is developed. Spectral crosstalk is corrected by exciting the fluorophores in a round-robin manner and synchronous emitted light collection. To report the performance of the multicolor microscopy, a simplified 3D tumor model is created by placing beads and spheroids inside a channel filled with the cell culture medium is imaged at varying exposure times. As a representative case and a method for bio-hybrid drug carrier fabrication, a spheroid surface is coated with beads in a channel utilizing electrostatic forces under the guidance of multicolor microscopy. Our experiments show that multicolor fluorescence microscopy enables crosstalk-free and spectrally-different individual image acquisition of beads, spheroids, and channels with the minimum exposure time of 5.5 ms. The imaging technique has the potential to monitor drug carrier transportation to cancer cells in real-time
Control of magnetotactic bacteria
Full text linkMagnetotactic bacteria hold promise in targeted therapy and nano-medicine. Their size, motility, and magnetic properties would enable directional control towards diseased cells and deep seated regions within the human body. In this chapter, we review culturing methods of Magnetospirillum Magnetotacticum Strain MS-1 and M. magneticum Strain AMB-1 and characterize their magnetic properties. We also present the directional control of magnetotactic bacteria using external magnetic fields and discuss some of their potential applications in nano-medicine.</p
IRONSperm swimming by rigid-body rotation versus transverse bending waves influenced by cell membrane charge
Full text linkCell membrane potential affects the electrostatic self-assembly of magnetizable nanoparticles around the flagellum of sperm cells, leading to the formation of biohybrid microrobots (i.e., IRONSperm) with various bending stiffness. Here we explain the influence of bull sperm cell membrane potential on the formation of two types of IRONSperm samples that are produced by electrostatic self-assembly. The first type is a proximal-coated soft body with nanoparticles concentrated on the head to maintain high flexibility of the flagellum and create a passively propagating transverse bending wave under the influence of an external rotating magnetic field. The second type is a rigid-body with nanoparticles approximately uniformly distributed along the length to provide arbitrary geometry that maintains a constant chiral shape and propel by rotation about its long axis. We present a magneto-elastohydrodynamic model to predict the swimming speed at low Reynolds number for rigid IRONSperm with arbitrary shapes, and show that decreasing the bending stiffness allows the model to capture the behavior of its soft counterpart. While the response of a rigid chiral IRONSperm is distinguished by a greater swimming speed with a smooth decay with frequency, the benefit of a soft flagellum in certain scenarios would present a much smaller range of frequencies for wireless actuation
Input-Output Boundedness of a Magnetically-Actuated Helical Device
No full textTo date, all previous research in the wireless magnetic actuation of untethered helical devices has achieved motion stability using feedback control in vitro. However, feedback control systems are likely to be affected by the increased sensory uncertainty during in vivo trials. In this study we investigate the input-output boundedness of an interconnection between a helical device and a single rotating magnet actuator in low-Reynolds-number regime. Using the resistive-force theory, the interconnection is expressed in terms of all possible inputoutput pairs. Inputs representing the actuation frequency, pitch angle, lateral speed, and field strength are analyzed numerically and experimentally. We demonstrate input-output boundedness of the states of the helical device during circular and straight runs in open-loop, and we demonstrate bounded input-output propulsion without orienting the angle of attack (the often used input to swim horizontally without vertical drift) of the helical device to counteract gravity. Our results are important for a number of minimally invasive applications and tasks requiring improved control authority for stable runs of helical devices without drift due to gravity and without feedback control and restricted configuration imposed on the helical device’s motion
Influence of Nanoparticle Coating on the Differential Magnetometry and Wireless Actuation of Biohybrid Microrobots
Full text linkMagnetic nanoparticles can be electrostatically assembled around sperm cells to form biohybrid micro robots. These biohybrid microrobots possess sufficient magnetic material to potentially allow for pulse-echo localization and wireless actuation. Alternatively, magnetic excitation of these nanoparticles can be used for localization based on Faraday's law of induction using a detection coil. Here, we investigate the influence of the electrostatic attraction between positively charged nanoparticles and negatively charged sperm cells on the activation of the nanoparticles during nonlinear differential magnetometry and wireless magnetic actuation. Activation of clusters of free nanoparticles and nanoparticles bound to the body of sperm cells is achieved by a combination of a high- frequency alternating field and a pulsating static field. The nonlinear response in both cases indicates that constraining the nanoparticles is likely to yield significant decreases in the magnetometry sensitivity. While the attachment of particles to the cells enables wireless actuation (rolling locomotion), the rate of change of the magnetization of the nanoparticles decreases one order of magnitude compared to free nanoparticles
- …
