Sediment size distribution at three rivers with different types of land use in Endau Catchment Area, Kluang, Johor, Malaysia

Land use along the river will determine the substrate size and distributions. Substrate particle size will influence aquatic life because substrate is one of the main components forming aquatic habitat. This aquatic habitat is very important in determining river water quality as well as river health. Therefore, identifying the sediment size distribution based on land use is very crucial in river maintenance. The objective of this study is to determine the particle size variation between upper reach and lower reach of the sampling station as well as variation from different land use cover at different sub-catchment areas. The pebble counts was conducted at upper reach station and lower reach station by applying the Pebble Count Protocols developed by the West Virginia Department of Environmental Protection and Wolmen Pebble Count Procedure. The average median (D50) for Dengar River ranged between 4.5 mm for upper portion and 2.4 mm for lower portion. Similar observations were found at the Mengkibol River, where particle size ranged between 3.0 mm for upper portion and 2.4 mm for lower portion. As for Madek River which represents land use area for logging activity, the results obtained were different in which the upper portion the particle size was smaller (D50 = 4.5 mm) than the lower portion (D50 = 41.5 mm). The finding of this study will be a basis for river catchment management study and can be used by river management authorities in the country for river management planning.Keyword: pebble count, sediment size, average median, fine gravel, very fine gravel, urban, oil palm, logging, land us

Effect of Monosodium Glutamate on the Digestibility of Different Nutrients Using Standardized Static In vitro Digestion Model

Monosodium glutamate (MSG) is a flavor enhancer and food additive with a unique umami taste. Due to its widespread use in humans, this study focused on the cytotoxicity, anti-diabetic effect, and interaction with protein digestion by performing a standardized static in vitro digestion model and lipid digestion by estimating free fatty acids released from 0.5 g of olive oil during intestinal lipolysis. The study showed that monosodium glutamate has an apparent cytotoxic effect on the Caco-2 cell line in a dose-dependent manner. MSG glutamate also showed low inhibitory activity on alpha-glucosidase enzyme even at high concentrations (16.3 % at 1800 ppm). By performing simulated in vitro digestion to study the interaction between MSG and protein digestion, followed by MTT study, total protein determination, and pH drop method, all results concluded that MSG affected proteolysis. Finally, the impact of MSG on lipolysis was studied through a free fatty acid release test. The results of the study demonstrated that MSG harmed fat digestibility in a concentration-dependent manner. As a result, it is essential to conduct further studies, especially in vivo studies, to determine the potential negative effects of MSG on human health

Scanning thermal microscopy and Raman analysis of bulk fused silica exposed to low-energy femtosecond laser pulses

Low energy femtosecond laser pulses locally increase the refractive index and the hydro-fluoric acid etching rate of fused silica. These phenomena form the basis of a direct-write method to fabricate integrated glass devices that are of particular interest for optofluidics and optomechanical applications. Yet the underlying physical mechanism behind these effects remains elusive, especially the role of the laser polarization. Using Scanning Thermal Microscope and Raman spectrometer we observe in laser affected zones, a localized sharp decrease of the thermal conductivity correlated with an increased presence of low-number SiO2 cycles. In addition, we find that a high correlation exists between the amount of structural changes and the decrease of thermal conductivity. Furthermore, sub-wavelength periodic patterns are detected for high peak power exposures. Finally, our findings indicate that, to date, the localized densification induced by femtosecond laser pulses remains well below the theoretical value achievable in mechanically densified silica

Towards a femtosecond laser micro-machined optofluidic device for distinguishing algae species

We demonstrate a small device with a microfluidic channel and an integrated waveguide as a compact rudimentary tool for the detection, real-time monitoring, and potentially classification of algae. In order to reduce parasitic noise the micro-device used a curved subsurface optical waveguide to illuminate particles transiting through a microfluidic channel. The changes in the transmitted signal are monitored using a quadrant-cell photo-detector. The signals wavelets from the different quadrants are used to qualitatively distinguish different families of algae. Additional information, such as flow direction, is also provided. The channel and waveguide are fabricated out of a monolithic fused-silica substrate using a femtosecond laser-writing process combined with chemical etching. This proof-of-concept device paves the way for more elaborate femtosecond laser-based optofluidic micro-instruments incorporating waveguide network designed for the real-time analysis of cells and microorganisms in the field

Effects of acceleration on the collision of particles in the rotating black hole spacetime

We study the collision of two geodesic particles in the accelerating and rotating black hole spacetime and probe the effects of the acceleration of black hole on the center-of-mass energy of the colliding particles and on the high-velocity collision belts. We find that the dependence of the center-of-mass energy on the acceleration in the near event-horizon collision is different from that in the near acceleration-horizon case. Moreover, the presence of the acceleration changes the shape and position of the high-velocity collision belts. Our results show that the acceleration of black holes brings richer physics for the collision of particles.Comment: 7 pages, 2 figures, The corrected version accepted for publication in EPJ

Low environmental impact method for controlling the peach fruit fly, Bactrocera zonata (Saunders) and the Mediterranean fruit fly, Ceratitis capitata (Wied.), in mango orchards in Egypt

The study was carried out at two experimental farms in Ismailia Governorate, Egypt, during season of 2015 and 2016. GF-120 (Conserve® 0.024% CB) was selected in this study to evaluate its efficacy for controlling the peach fruit fly, Bactrocera zonata (Saunders) and the Mediterranean fruit fly, Ceratitis capitata (Wied.), on mango fruits by using partial bait spray and spots method. GF-120 was used as low environmental impact method and new way to control B. zonata and C. capitata, compared with malathion 57%, as traditional insecticide. During both seasons, data revealed that the number of C. capitata captured weekly from different treatments and untreated plots was higher than the number of B. zonata captured in both seasons of experiment. Data revealed that the number males of B. zonata and C. capitata captured weekly from sticky traps were lower in trees treated with GF- 120 than malathion and untreated plots. In the farm of Faculty of Agriculture, Suez Canal University, the lowest percentages of infestation of both dropping and setting fruits per tree were recorded in plots treated with GF120 (spots), with an average of 25.14 and 17.022% for dropping fruits and 2.2 and 2.0% for setting fruits for 2015 and 2016 season, respectively. Data indicated that the all tested formulation under field condition caused significant reduction in the rate of infestation from 54.92 to 81.79 for both dropping and setting fruits. The lowest percentages of infestations in the private farm of both dropping and setting fruits per tree were recorded in GF-120 (spray treatment), with an average of 20.0, 12.12 for dropping fruits and 3.4 and 4.0 for setting fruits for 2015 and 2016 seasons, respectively

Binding Energy of Hydrogen-Like Impurities in Quantum Well Wires of InSb/GaAs in a Magnetic Field

The binding energy of a hydrogen-like impurity in a thin size-quantized wire of the InSb/GaAs semiconductors with Kane’s dispersion law in a magnetic fieldBparallel to the wire axis has been calculated as a function of the radius of the wire and magnitude ofB, using a variational approach. It is shown that when wire radius is less than the Bohr radius of the impurity, the nonparabolicity of dispersion law of charge carriers leads to a considerable increase of the binding energy in the magnetic field, as well as to a more rapid growth of binding energy with growth ofB

Critical exponents and equation of state of the three-dimensional Heisenberg universality class

We improve the theoretical estimates of the critical exponents for the three-dimensional Heisenberg universality class. We find gamma=1.3960(9), nu=0.7112(5), eta=0.0375(5), alpha=-0.1336(15), beta=0.3689(3), and delta=4.783(3). We consider an improved lattice phi^4 Hamiltonian with suppressed leading scaling corrections. Our results are obtained by combining Monte Carlo simulations based on finite-size scaling methods and high-temperature expansions. The critical exponents are computed from high-temperature expansions specialized to the phi^4 improved model. By the same technique we determine the coefficients of the small-magnetization expansion of the equation of state. This expansion is extended analytically by means of approximate parametric representations, obtaining the equation of state in the whole critical region. We also determine a number of universal amplitude ratios.Comment: 40 pages, final version. In publication in Phys. Rev.