Band Rejections for WLAN and WIMAX Utilizing UWB Planar Antenna by Slits in the Conductor Elements

Band rejections for WLAN and WIMAX frequency bandwidths are realized in a UWB planar antenna utilizing a single slit in an elliptical element. WLAN and WIMAX communication system frequency bandwidths have been known to coexist with the UWB frequency bandwidth. Coexistence of multiple frequency bandwidths are susceptible to disadvantage and could cause interferences to other communication system. The disadvantages could be in form of signal disruption, data loss and equipment malfunctions [1-3]. Thus, it is essential to eliminate WLAN frequency bandwidth from the UWB communication system. Slits are employed to influence the exterior current distribution on the radiator and therefore, has generated mismatched of the input impedance. The phenomenon has caused the band notch characteristic and thus, rejected the frequency bandwidths for 5 to 6 and 3.3 to 3.7GHz, respectively. The structures of the slits are simple in a compact design of the UWB planar antenna. The UWB planar antennas with band rejections are compared with the reference antenna. The reflection coefficients S11 for the designed UWB planar antennas have rejected the frequency bandwidths for 5 to 6 and 3.3 to 3.7GHz, consecutively. The peak of the notched-band reflection coefficient S11 for the frequency bandwidths 5 to 6 and 3.3 to 3.7GHz are about -3 and -4dB, respectively. Surface currents are distributed in the slit areas. The radiation patterns are illustrated for the frequency 3.5, 7.5 and 9.5GHz for the single notched-band, while 4.5, 7.5 and 9.5GHz for the dual notched-band characteristics. Radiation patterns for the single and dual notched-band in the H- and E-planes for the designed antennas are in omni- and bi-directional, respectively. Maximum gains G are in the –z and –x direction in the H- and E- plane, for the UWB planar antenna with single and dual notched-band characteristics

Tindakan minyak kelapa dara terhadap tulang osteoporosis pascamenopaus: analisis gen Osteoblastogenesis dan antioksidan

Osteoporosis pascamenopaus merupakan salah satu masalah kesihatan utama yang melanda kaum wanita berumur. Ia disebabkan oleh beberapa faktor termasuk tekanan oksidatif, yang dipercayai dapat dikawal melalui pengambilan antioksidan daripada sumber makanan. Minyak kelapa dara (VCO) merupakan salah satu hasil semula jadi yang kaya dengan antioksidan dan telah dibuktikan mampu memelihara tulang yang mengalami osteoporosis. Kajian ini dijalankan untuk mendapatkan kefahaman yang lebih mendalam tentang aktiviti minyak kelapa dara terhadap osteoporosis pada peringkat molekular. Tiga puluh dua ekor tikus betina Sprague-Dawley dibahagikan kepada empat kumpulan, iaitu kumpulan pembedahan Sham, kawalan terovariektomi (Ovx+Ctrl), kumpulan terovariektomi dengan rawatan VCO (Ovx+VCO) dan kumpulan terovariektomi dengan rawatan estrogen (Ovx+E). Kesemua rawatan diberikan melalui oral selama sepuluh minggu. Sampel tulang femur tikus diambil untuk mengkaji perubahan pada ekspresi gen superoksida dismutase (SOD), glutation peroksidase (GPX), osteokalsin dan transkripsi faktor 2 berkaitan run (Runx2). Hasil kajian mendapati bahawa tikus yang menerima rawatan VCO mengalami peningkatan yang signifikan pada ekspresi gen SOD, GPX dan osteokalsin berbanding kumpulan kawalan terovariektomi, disamping ekspresi gen Runx2 yang turut menunjukkan pola peningkatan. Secara kesimpulannya, VCO membantu memelihara tulang pada tikus model osteoporosis melalui tindakannya meningkatkan ekspresi gen antioksidan serta gen yang menigkatkan aktiviti sel osteoblas

Market reactions towards the announcement of Sukuk issuance: evidence from Malaysian market

Drawing from the significance and implication that investors can use to properly comprehend the trend in market reaction from the new issuance of information, this study aims to investigate the market’s reaction toward the announcement of Islamic bond or sukuk. The Islamic bond market provides not only an avenue for more dynamic capital trades and portfolio diversification but also functions as an engine that accelerates the growth of the Islamic capital market. This study specifically aims to investigate whether the announcements of sukuk issuance that carry any new information can create impact on the market’s reactions. The overall sample time frame for this study is divided into three event windows; before, during and after the financial crisis in order to ascertain any unusual impact on the market’s return during the 2007-2008 financial crises. The stock market return is measured via the FTSE and Bursa Malaysia’s KLCI. In order to offer a more robust finding on the returns, this study re-measured the market return using Bursa Malaysia’s FTSE EMAS Index as it is a better representation of the sample population. The data collected from Bursa Malaysia, Bloomberg and DataStream database will be then analysed using Brown and Warner’s standard event study methodology of Brown and Warner (1985). Based on the 115 sukuk issuances between 2002 and 2013 (a period of 12 years), this study reveals that the effect of the announcement is significantly negative a day before and on the announcement date. On top of that, the result finds that there is a significantly positive reaction 30 days after the announcement of sukuk issuance which indicates that investors take a longer time to absorb the information from the sukuk announcement. The existence of a significantly positive reaction of stock markets during the financial crisis periods could be attributed to the conditions where the Islamic debt issuance might have sent an incredible signal about the financial position of the company, which have helped in solving the financial problem, especially during the economic downturn. However, the EMAS Index shows none of these significant results. The significant findings in this study (i.e., when uses the KLCI) are expecting to contribute clearer evidence and strategies concerning whether the information regarding sukuk can help investors to form a better investment strategy

Pump power distribution in bidirectional pumped dual-stage L-band EDFA

Bidirectional pumped dual-stage L-band EDFA utilizing a single power splitter and pump laser has been presented in this paper. A power splitter has been used to distribute the pump power bidirectionally to pump two EDFs with different length. An average gain of 18.6 dB with average NF of 8.6dB has been attained when the signal is equal to 0 dBm ranging from 1570 nm to 1605 nm signal. By using a single pump simultaneously with low gain ripple of less than 0.7 dB throughout the L-band transmission window

The Comprehensive Review of Neural Network: An Intelligent Medical Image Compression for Data Sharing

In the healthcare environment, digital images are the most commonly shared information. It has become a vital resource in health care services that facilitates decision-making and treatment procedures. The medical image requires large volumes of storage and the storage scale continues to grow because of the advancement of medical image technology. To enhance the interaction and coordination between healthcare institutions, the efficient exchange of medical information is necessary. Therefore, the sharing of the medical image with zero loss of information and efficiency needs to be guaranteed exactly. Image compression helps ensure that the purpose of sharing this data from a medical image must be as intelligent as possible to contain valuable information while at the same time minimizing unnecessary diagnostic information. Artificial Neural Network has been used to solve many issues in the processing of images. It has proved its dominance in the handling of noisy or incomplete image compression applications over traditional methods. It contributes to the resulting image by a high compression ratio and noise reduction. This paper reviews previous studies on the compression of intelligent medical images with the neural network approach to data sharing

PAPR reduction techniques in generalized inverse discrete fourier transform non-orthogonal frequency division multiplexing system

A promising system of Generalized Inverse Discrete Fourier Transform Non-Orthogonal Frequency Division Multiplexing (GIDFT n-OFDM) system can fulfil the requirement of supporting higher data rate in Fifth Generation (5G) technology. However, this system experience High Peak to Average Power Ratio (PAPR) due to massive number of subcarriers signal is transmitted. In this paper, three types of usual PAPR reduction techniques were applied in GIDFT n-OFDM system which are Clipping, Partial transmit Transform (PTS) and Selective Mapping (SLM). The system performance is compared and evaluated using Complementary Cumulative Distribution Function (CCDF) plot. Simulation results show that SLM technique give significant reduction of PAPR 9 dB of the original performance

Market reactions towards the announcement of sukuk issuance: evidence from Malaysian market / Muzrifah Mohamed, Norliza Che Yahya and Nur Ashikin Ishak

One of the unique features of Malaysian financial market is the co-existence of Islamic bonds market or better known as sukuk market and the conventional bonds. Unlike conventional bonds, the Islamic bonds are structured to comply with Shariah principles, which prohibits the charging of riba' or interest. The history of sukuk market records Malaysia as one of the pioneering countries of Islamic bond products when it kicks off the global sukuk arena with the issuance of Shell MDS Sdn Bhd in 1990 ("Bloomberg Businessweek," 2013). The issuance of Shell MDS Sdn Bhd has been the spectator of the unprecedented proliferation for sukuk issuance especially after the global financial crisis in 2007-2008. The global financial crisis has alerted investors on the significance of other investment alternatives as a means to diversify and minimise the risk of their investment portfolio. To totally be dependent on the equity market might limit the investors' chance to optimise their portfolio return particularly during the economic downturn; sukuk is viewed as one of the best alternatives for risk diversification strategy. To date, sukuk is reported as the most active Islamic financial instrument issued in debt market and an important avenue for fundraising mechanism for companies and also as investment activities for investors. As depicted in Figure 1, even though the total number of global sukuk issuance experienced a temporary drop in the year 2008, it regained its momentum in 2009. The consistent growth of its size issued from year to year indicates that the global sukuk market is gradually developing. In other words, the debt market participants (e.g. firms and investors) have begun to recognise the significance of sukuk as an alternative investment channel. Further on the statistic, despite a decline in the total amount of sukuk issuance in 2008, Malaysia is still positioned as the largest sukuk market in the world during and after the financial crisis (Bank Negara Malaysia and Securities Malaysia, 2009)

Ultra-wideband planar antenna with notched-band for WIMAX, WLAN and MSAT applications

Ultra-wideband (UWB) with triple band notch characteristics was presented. WIMAX, WLAN and Meteorological Satellite (MSAT) frequency bandwidths were rejected in the UWB planar antenna composed from a single layer conductor element. Frequency bandwidths for WIMAX, WLAN and MSAT are allocated at 3.3~3.7, 5~6 and 7.4~8.4GHz, respectively. Conductor element etching method was used as the means to realize the band notch characteristics as it was considered convenient and simple. Two slits were etched on the ground plane while on the elliptical element, a single slit. The slits were designed for simplicity in the means of achieving the desired band notch characteristics. The proposed antenna design was compact and low profile. The antenna performances were compared with the reference antenna and the results were negligible

Bone turnover and oxidative stress markers in estrogendeficient rats treated with Marantodes pumilum leaves and roots: A comparative study

Purpose: To investigate the relative changes in bone turnover and oxidative status markers of estrogen-deficient rats treated with Marantodes pumilum var. alata (MPva) leaf and root extracts.Methods: Thirty-six female Sprague-Dawley rats were divided into 6 groups (n = 6), namely: baseline (BL); placebo surgery (PS); ovariectomized control (OVXC); estrogen treatment (ERT); leaf extract treatment (MPv); and root extract treatment (MPr). Rats in all groups, except BL and PS, were ovariectomized to induce menopause. Through the oral route, ERT received 64.5 μg/kg/day estrogen (Premarin®); MPv received 20 mg/kg/day leaf extracts of MPva; MPr received 20 mg/kg/day root extract of MPva; while BL, OVXC, and PS served as untreated controls. At the end of 8 weeks treatment, blood and bone samples were collected for assay of bone turnover markers (osteocalcin and pyridinoline) and oxidative status markers (4-hydroxynonenal, superoxide dismutase, and glutathione peroxidase) using enzyme-linked immunosorbent assay (ELISA).Results: Significantly higher (p < 0.05) bone level of glutathione peroxidase was seen in MPv when compared with BL and OVXC. MPv also showed lower bone level of pyridinoline (p<0.05) compared to OVXC. Bone level of 4-hydroxynonenal in both MPv and MPr groups was significantly reduced (p < 0.05) when compared with OVXC.Conclusion: MPva leaf showed more remarkable effects on bone turnover and oxidative stress markers of ovariectomized rats than its roots and estrogen treatment. Thus, the use of MPva leaf, as an alternative to estrogen for treating postmenopausal osteoporosis, would be preferred to its roots.Keywords: Phytoestrogens, Osteoporosis, Marantodes pumilu