Single-, Dual- and Triple-band Frequency Reconfigurable Antenna

The paper presents a frequency reconfigurable slot dipole antenna. The antenna is capable of being switched between single-band, dual-band or triple-band operation. The antenna incorporates three pairs of pin-diodes which are located within the dipole arms. The antenna was designed to operate at 2.4 GHz, 3.5 GHz and 5.2 GHz using the aid of CST Microwave Studio. The average measured gains are 1.54, 2.92 and 1.89 dBi for low, mid and high band respectively. A prototype was then constructed in order to verify the performance of the device. A good level of agreement was observed between simulation and measurement

Wide to multiband elliptical monopole reconfigurable antenna for multimode systems applications

Wideband-multiband reconfigurable elliptical monopole antenna is investigated in this paper. By having conventional elliptical monopole antenna, wideband operating frequency is obtained. With the combination of dual pairs of slotted arms and a band-pass filter on the ground plane of the elliptical monopole, multiband is achieved. Dual-band operating frequencies at 1.6 GHz and 2.6 GHz while wideband operates from 3.35 GHz to 9 GHz. Therefore, wide range of wireless communication systems is obtained from the proposed antenna to support the multiband mode (i.e. GPS and LTE) and UWB systems. Frequency reconfigurable is achieved by controlling the switches integrated on the antenna structure. Simulated results of reflection coefficient, radiation patterns and gain performance are presented. The proposed antenna design is suitable candidate for different wireless communication applications

Preventive potential of andrographis paniculata-derived compounds in metabolic syndrome-associated prostate cancer: a narrative review on the mechanism of action

Metabolic syndrome (MetS) and prostate cancer (PCa) are among the diseases with a concerning prevalence. The reported cases for both medical dilemmas have been steady with no sign of abating at the moment. More worrying is that researchers have started to discover that some of the components of MetS associatively worsen the prognosis of PCa. Even though the relationship is not fully known, its manifestation could cause extra burden to the currently implemented treatment approaches. The use of plant bioactive compounds as an alternative treatment has gained recognition, provided that its mechanisms of action, tolerability, efficacy, safety, and cost-effectiveness are well understood. Therefore, the current review intended to highlight the potential of bioactive compounds derived from plants to simultaneously target MetS, PCa, and MetS-PCa codisease. Additionally, emphasis on the potential of Andrographispaniculata (AP) as a candidate for the treatment of MetS-PCa is also highlighted

Sediment and carbon accumulation in sub-tropical salt marsh and mangrove habitats of north-eastern coast of Bay of Bengal, Indian Ocean

Researches on salt marsh mangrove habitats as global carbon sink are increasing worldwide. However, uncertainties in measuring carbon sequestration capacity of the vulnerable subtropical South Asian coastal habitat thus obstructing the mapping sediment and carbon accumulation rate of their importance.The present investigation was carried out to assess the sedimentation and carbon accumulation rate in salt marsh and mangrove habitats in the vicinity of Sitakunda coast, Chittagong, Bangladesh. The data indicate that sedimentation rate was 22.76±2.56 mg/cm2/day in mangrove area, 63.52±7.42 mg/cm2/day in lower mangrove area, 97.02±6.64 mg/cm2/day in higher marsh area, 5.91±1.16 mg/cm 2/day in lower marsh area and 9.81±0.03 mg/cm2/day in muddy area. The average sedimentation rate was found 39.82±6.72 mg/cm2/day during the study period. Soil organic matter in the newly deposited sediment was 3.89±1.28%, while 3.57±0.77% in accumulated peat sediment.Organic carbon of the newly deposited sediment was 2.05±0.93% and 1.89±0.55% in accumulated peat sediment. Usually, the organic materials were found higher in the peat soil in the wetland habitat, while lower amount of organic materials are found in the present peat soil. Lower amount of organic materials in peat soil in the study area could probably due to higher utilization of organic materials by aquatic plants. Further, uncertainties remain about sediment and carbon accumulation changes with tidal range, latitude and elevation in study area require long-term spatio-temporal investigation

THREE-DIMENSIONAL RECORDING AND PHOTOREALISTIC MODEL RECONSTRUCTION FOR VIRTUAL MUSEUM APPLICATION – AN EXPERIENCE IN MALAYSIA

In recent years, museums are utilizing the ability of virtual reality (VR) technologies to visualize their collections in three-dimensional (3D) environment. The demands for 3D digitization of cultural heritage have increase greatly to facilitate the development of virtual museum. Among the available techniques, the use of laser scanning for digital recording and 3D reproduction of the heritage sites and archaeological artefacts are technically more reliable due to its rapid and high resolution data capture. However, the suitable 3D laser scanners used greatly depend on the level of details and size of an object. This research used medium and close-range type of laser scanners to digitally record the heritage objects. The aim of this research was to develop methodology framework for digital recording and 3D reproduction of archaeological artefact and heritage sites in Malaysia by using terrestrial laser scanning technology. Besides, this research focused on the reconstruction of photorealistic 3D models based on the colour information yield by close-range photogrammetry. The colour descriptions were obtained either by built-in camera or externally integrated camera on the laser scanner. For better colour descriptions, external images were captured by independent Nikon D300s digital camera. The geometric model accuracy of A’Famosa and terracotta Buddha statuette was in 5 mm and 0.41 mm respectively. 3D flythrough animation was rendered by using the coloured point clouds model. The development of 3D Virtual Walkthrough Museum (3DVWM) utilized the 3D PDF document and SCENE WebShare platform to offer realistic visualization experience to the visitors where the reality-based models could be manipulate in 3D geometric aspects and use of metric analysis. Thus, 3DVWM can facilitate the virtual museum application in Malaysia and enable wider visitors to virtually appreciate the cultural heritage in Malaysia. Thus, this indirectly stimulates the tourism industry in our country

Determining the Solar Radiation in Ayer Keroh, Melaka by using Hargreaves Method

This analysis is conducted to determine the ability of Hargreaves method that uses temperature difference and the latitude of the location to estimate the solar radiation. Location of the data is measured is at the weather station at Kompleks Makmal Fakulti Kejuruteraan Mekanikal, Universiti Teknikal Malaysia Melaka, Ayer Keroh (2.2667N,102.2833E). The measured and estimated data solar radiation were analyzed and evaluated by using graphical and statistical method. The analysis shows that there is 61.56% difference between the estimated and measured data and the estimated data is over-estimated. After consideration of other factor that can affect the estimated solar radiation data, the Hargreaves method is considerably suitable for estimating solar radiation of a location

Fluorescent Probes for Ecto-5′-nucleotidase (CD73)

Ecto-5′-nucleotidase (CD73) catalyzes the hydrolysis of AMP to anti-inflammatory, immunosuppressive adenosine. It is expressed on vascular endothelial, epithelial, and also numerous cancer cells where it strongly contributes to an immunosuppressive microenvironment. In the present study we designed and synthesized fluorescent-labeled CD73 inhibitors with low nanomolar affinity and high selectivity based on N6-benzyl-α,β-methylene-ADP (PSB-12379) as a lead structure. Fluorescein was attached to the benzyl residue via different linkers resulting in PSB-19416 (14b, Ki12.6 nM) and PSB-18332 (14a, Ki2.98 nM) as fluorescent high-affinity probes for CD73. These compounds are anticipated to become useful tools for biological studies, drug screening, and diagnostic applications

Caloric restriction improves glycaemic control without reducing plasma branched-chain amino acids or keto-acids in obese men

Higher plasma leucine, isoleucine and valine (BCAA) concentrations are associated with diabetes, obesity and insulin resistance (IR). Here, we evaluated the effects of 6-weeks very-low calorie diet (VLCD) upon fasting BCAA in overweight (OW) non-diabetic men, to explore associations between circulating BCAA and IR, before and after a weight loss intervention. Fasting plasma BCAAs were quantified in an OW (n = 26; BMI 32.4 ± 3 kg/m2; mean age 44 ± 9 y) and a normal-weight (NW) group (n = 26; BMI 24 ± 3.1 kg/m2; mean age 32 ± 12.3 y). Ten of the OW group (BMI 32.2 ± 4 kg/m2; 46 ± 8 y) then underwent 6-weeks of VLCD (600–800 kcal/day). Fasting plasma BCAA (gas chromatography-mass spectrometry), insulin sensitivity (HOMA-IR) and body-composition (DXA) were assessed before and after VLCD. Total BCAA were higher in OW individuals (sum leucine/isoleucine/valine: 457 ± 85 µM) compared to NW control individuals (365 ± 78 µM, p < 0.001). Despite significant weight loss (baseline 103.9 ± 12.3 to 93 ± 9.6 kg and BMI 32.2 ± 4 to 28.9 ± 3.6 kg/m2), no changes were observed in BCAAs after 6-weeks of VLCD. Moreover, although VLCD resulted in a significant reduction in HOMA-IR (baseline 1.19 ± 0.62 to 0.51 ± 0.21 post-VLCD; p < 0.001), Pearson’s r revealed no relationships between BCAA and HOMA-IR, either before (leucine R2: 2.49e−005, p = 0.98; isoleucine R2: 1.211−e006, p = 0.9; valine R2: 0.004, p = 0.85) or after VLCD (leucine R2: 0.003, p = 0.86; isoleucine R2: 0.006, p = 0.82; valine R2: 0.002, p = 0.65). Plasma BCAA are higher in OW compared to NW individuals. However, while 6-weeks VLCD reduced body weight and IR in OW individuals, this was not associated with reductions in BCAA. This suggests that studies demonstrating links between BCAA and insulin resistance in OW individuals, are complex and are not normalised by simply losing weight