A sensitive acoustic sensor using fiber bragg grating based on strain compensation

An acoustic sensitivity single ring fiber sensor with enhanced pressure sensitivity is designed by using Fiber Bragg Grating (FBG). Measurement sensitivity of the this fiber sensor is 0.3714 με/Hz. This sensor exhibited a good acoustic sensitivity, showing that the sensor has good sensing properties for the detection of the acoustic signals

Isolation and Identification of Bacteria-producing Cellulose from Tropical Fruit for Halal Capsule Application

Bacterial cellulose (BC) is pure cellulose synthesized by various species of bacteria. Raising demands on bacterial cellulose is due to its pure and simpler structure. It has plenty of applications in various industries such as food, medical and cosmetics, rendering it a choice in halal industry application as a substitute for non-halal gelatine. However, challenges arise during the BC production such as high production cost and low volumetric yield. In this study, BC is studied to overcome the barriers to BC production. Isolation and identification of cellulose producing bacteria were carried out on eight different tropical fruit sources using Hestrin-Schramm media in static culture condition. Morphological and molecular identification by microscopic observation, gram staining, and 16S rRNA analysis were conducted to identify the characteristics and strain of the new isolates. Next, the selected colonies were challenged to grow in agitating condition using modified HS media. The effects of carbon concentration and agitation speed on the production of cellulose were investigated using on central composite design (CCD). Three new cellulose producing bacteria were successfully isolated and identified to be similar to Enterobacter sp. SJZ-5, Bacterium sp NLAE-zl-H356, and Bulkhoderia sp. RD_DACAR_02 through morphological and molecular analysis. The most potent strain which is similar to Enterobacter sp. SJZ-5 (named as Enterobacter sp.M003) has been chosen for BC optimization study for high BC production using modified HS media. Optimization of bacterial cellulose production using response surface methodology (RSM) with 13 runs indicated that the optimal production parameters were 17.5 g/L for carbon concentration at 277 rpm for agitation speed gave 1.7g/L cellulose. It is expected that the newly isolated bacteria will be able to provide an alternative to gelatine for halal capsule production, thus minimizing and replacing non-halal gelatine usage

Warga emas dan pilihan penempatan di pusat jagaan harian

Kajian ini bertujuan untuk meneroka faktor pendorong penempatan warga emas di pusat jagaan harian dan kelebihan yang diperoleh oleh golongan ini setelah tinggal di situ. Selain itu, kajian ini juga bertujuan untuk mengenal pasti kepuasan warga emas terhadap pusat jagaan harian dalam menjalani rutin seharian. Seramai dua puluh lima orang warga emas yang terdiri daripada wanita dan beragama Islam di pusat jagaan Rumah Ibuku Sayang Ar Rayyan, Seremban, Negeri Sembilan dipilih sebagai sampel dengan menggunakan kaedah persampelan bertujuan. Temu bual berstruktur berbantukan borang soal selidik digunakan untuk mendapatkan maklumat daripada warga emas yang dikaji. Hasil kajian mendapati bahawa kesunyian tinggal di rumah, jaminan keselamatan dan pilihan sendiri untuk tinggal di pusat jagaan harian merupakan tiga faktor utama yang mendorong warga emas memilih untuk ditempatkan di pusat jagaan Rumah Ibuku Sayang Ar Rayyan. Hasil kajian juga mendapati bahawa kemudahan menuntut ilmu agama dan beribadah, aktiviti-aktiviti yang efektif, peluang persahabatan, jaminan keselamatan dan jaminan kesihatan merupakan kelebihan yang diperoleh oleh warga emas di tempat ini. Warga emas berasa lebih tenang, dapat melibatkan diri dalam pelbagai aktiviti yang berfaedah dan menikmati pelbagai kemudahan yang disediakan bagi memenuhi keperluan mereka. Oleh itu, Rumah Ibuku Sayang Ar Rayyan memainkan peranan yang penting dalam menyediakan sokongan sosial yang amat diperlukan dalam kehidupan warga emas beragama Islam yang ditempatkan di pusat jagaan harian ini

IMPROVING FERTILITY OF ACID SULFATE SOIL USING VARIOUS LIME SOURCES FOR RICE GROWN IN MALAYSIA

The main problems of acid sulfate soils are high acidity and Al and/or Fe toxicity to the soil. This problem causes rice root inhibition, hence retard plant nutrient uptake for its growth. Improving these conditions is important; hence, liming seems to be a common practice to ameliorate this soil, especially for rice cultivation. A study was conducted to evaluate the effects of applying ground magnesium limestone (GML), hydrated lime and liquid lime on the growth of rice under glasshouse conditions. MR 219 rice variety was used in this experiment. It was found that the application of 4 t ha-1 of GML had produced the highest rice yield of 8.2 t ha-1 under glasshouse condition. The result showed that as panicle length increase, spikelet per panicle also increases. Relative rice yield is negatively correlated with the soil pH, and this indicates that as soil acidity increase (observed with pH between 2 to 3), the rice yield decreases and vice versa. At harvest, due to liming practices, the soil pH exceeded 6 for all the treatment. It was also observed that as soil exchangeable Ca increase, soil pH also increases. Among the treatment, soil treated with 2 t ha-1 of hydrated lime gave the highest exchangeable Ca in the soil of 11.86 cmolc kg-1 soil with Ca concentration of 0.12% in the root. It was observed that liming increases soil pH and exchangeable cations in the soil. Therefore, liming is essential to ameliorate the acid sulfate soils for rice cultivation

Identifikasi Bioaktif Golongan Flavonoid Tanaman Anting-Anting (Acalypha Indica L.)

– Indonesia merupakan negara dengan kekayaan alam yang melimpah. Namun, untuk jenis tumbuhan, baru sekitar 8% yang dimanfaatkan sebagai tanaman pangan, obat-obatan, sumber kayu, dan tanaman hias. Salah satu tanaman yang berpotensi sebagai tanaman obat adalah Acalypha indica. Penelitian sebelumnya menunjukkan bahwa ekstrak tanaman ini memiliki aktivitas antibakteri Salmonella. Namun profil senyawa metabolit apa saja yang terkandung masih belum banyak diteliti. Fraksinasi senyawa metabolit dilakukan dengan kromatografi kertas pada ekstrak etanol (akar, batang, dan daun) tanaman Acalypha menggunakan eluen BAW (Butanol: Asam asetat: Air = 4:1:5) dan asam asetat 15%. Jumlah, letak, warna, dan nilai Rf bercak kemudian digunakan sebagai pedoman identifikasi dan menduga golongan flavonoid. Spektrofotometri serapan panjang gelombang maksimum dilakukan sebagai konfirmasi dugaan golongan flavonoid. Ketiga organ utama tanaman anting-anting (akar, batang, dan daun) memiliki distribusi kandungan senyawa yang berbeda-beda namun dengan jenis yang hampir sama. Golongan flavonoid yang berhasil teridentifikasi dari ketiga organ antara lain isoflavon, flavon, flavonol, flavanon, dihidroksiflavonol, khalkon, dan antosianidin. Organ daun memiliki keragaman kelas flavonoid lebih banyak dibanding akar dan batang

Directional felling within selective management system of Peninsular Malaysia: comparison between current and extended techniques

Directional felling has been implemented in Peninsular Malaysia as part of the Selective Management System (SMS) to obtain optimum yield from the forest resources while reducing damage to the environment and residual trees. Some questions regarding its effectiveness have been questioned a few times, resulting in a joint research project at Ulu Jelai Forest Reserve, Pahang, Malaysia to compare between the current directional felling technique and the new (extended) techniques, in terms of accuracy of tree felling, volume of felling logs, expected damage on residual trees, and time taken for tree felling. For this study, 38 trees were felled with the current and extended techniques. By using the extended technique, 91.3% of the trees were felled within the 0°-5° range, and 100% within the 0°-10° range, compared to 28.01% (within the 0°-5° range) using the current technique. The extended technique also recorded higher volume recovery (14% higher) and lower damage on the residual trees by almost 50%. However, the extended technique took longer time, i.e. 4.56 minutes per tree, as compared to 2.50 minutes. The main contributor to the difference is the presence of gauge cut in the extended technique. Generally, the studies suggest that the extended technique is preferred as it is safer to the feller and surrounding people, while reducing the collateral damage on the harvested trees, as well as the residual trees

Tunable indium tin oxide thin film as saturable absorber for generation of passively Q-switched pulse erbium-doped fiber laser

A tunable Q-switched pulse erbium-doped fiber (EDF) laser using indium tin oxide (ITO) thin-film-based saturable absorber (SA) is proposed and demonstrated. The SA is formed by depositing an ITO layer using DC magnetron sputtering on the fiber ferrule, which can be easily fabricated in less than 200 s with thickness of 17.80 nm. The proposed tunable Q-switched pulse EDF laser is operated from 1540.0 to 1570.0 nm, covering a total wavelength of 30.0 nm. The generated output pulses displayed a repetition rate range between 21.70 and 94.34 kHz. The shortest pulse width retrieved is 3.22 ls at the maximum pump power of 378.6 mW, while the maximum pulse energy recorded is 30.29 nJ. To the best of the authors’ knowledge, this appears to be the first proposed tunable passively Q-switched pulse EDF laser using ITO that serves as SA, which can promote ITO film in the application of ultrafast photonics

A report of natural enemies of papaya mealybug, paracoccus marginatus (Hemiptera: Pseudococcidae) in Peninsular Malaysia

Papaya mealybug is notorious pest of papaya & other horticultural crops. Keeping in mind the role of parasitoids and predators in pest management, an exploratory study was conducted on the availability of natural enemies of recently introduced papaya mealybug, Paracoccus marginatus in Selangor and Negri Sembilan states of Peninsular Malaysia. Results revealed the presence of two predators (Cryptolaemus montrouzieri and Apertochrysa sp.), one primary parasitoid (Acerophagus papayae) and three hyperparasitoids (Chartocerus sp., Marietta leopardina and Cheiloneurus sp.). Among all natural enemies recorded, populations of C. montrouzieri and A. papayae were frequently recorded from all sampled locations of the two states. Accordingly, these two species should be exploited for their potential to manage populations of P. marginatus below threshold levels

Passively mode-locked fiber laser by utilizing TTG film on a D-shaped fiber as a saturable absorber

In this paper, we propose a mode-locked fiber laser by utilizing single layer Trivial Transfer Graphene film (TTGF) as a saturable absorber (SA). The SA was deposited on the top of a side-polished D-shaped fiber. The SA was then integrated in the ring cavity configuration, with a clockwise light propagation. Three distinctive 2 m erbium doped fibers (EDFs) those are Metro-Gain15 EDF, Iso-Gain6 EDF and Iso-Gain12 EDF were used as gain media, interchangeable in the experiment. From the results, the Metro-Gain15 EDF gives the most proficient gain medium on generating a passively mode-locked fiber laser. The Metro-Gain15 Erbium doped mode-locked Laser was successfully producing ultrashort pulse with 8 nm spectral band-width, 13 MHz of repetition rate and 915 fs pulse duration. These outcomes demonstrated that TTGF deposited on the D-shaped fiber is a suitable component as an SA to produce a stable output passively mode-locked fiber laser for many optical fiber applications