Previously uncharacterized rectangular bacteria in the dolphin mouth

Much remains to be explored regarding the diversity of host-associated microbes. Here, we report the discovery of microbial structures in the mouths of bottlenose dolphins that we refer to as rectangular cell-like units (RCUs). DNA staining revealed multiple paired bands that suggested cells in the act of dividing along the longitudinal axis. Deep sequencing of samples enriched in RCUs through micromanipulation indicated that the RCUs are bacterial and distinct from Simonsiella, a genus with somewhat similar morphology and division patterning found in oral cavities of animals. Cryogenic transmission electron microscopy and tomography showed that RCUs are composed of parallel membrane-bound segments, likely individual cells, encapsulated by an S-layer-like periodic surface covering. RCUs displayed pilus-like appendages protruding as bundles of multiple threads that extend parallel to each other, and splay out at the tips and/or intertwine, in stark contrast to all known types of bacterial pili that consist of single, hair-like structures. These observations highlight the diversity of novel microbial forms and lifestyles that await discovery and characterization using tools complementary to genomics such as microscopy.

Non-conventional Band-notched UWB Antenna Design Based on Genetic Algorithm

In this paper, an improved applied approach based on Genetic Algorithm (GA) for antenna design is presented. It is basically useful to overcome electromagnetic interferences in UWB applications. First, an antenna in the range 2.8 - 20 GHz including UWB band was designed by using GA, then the undesired WiMAX band (3.5-3.8GHz) is rejected by optimizing appropriate Defected Ground Structure (DGS) filter. The proposed non-conventional filter consists of a matrix of rectangular cell shapes where each one is allocated by presence or absence of metal. The process is implemented in CST software using visual basic script. The method overcomes difficulties of conventional design. Furthermore, the optimized shape can be automatically obtained without appealing expert designers. Simulated and measured results demonstrate the effectiveness of the proposed design approach.

3D Natural State Modeling of Mount Iyang-Argopuro Geothermal Area, East Java, Indonesia

Mount Iyang-Argopuro is one of the geothermal working areas in the East Java. Mount Iyang-Argopuro has the potential of 185 MWe of reserves and 110 MWe of resources. It is estimated to have a liquid dominated reservoir with temperature up to 250-275 oC. An early 3D natural state numerical model of Mount Iyang-Argopuro Field is created using TOUGH2 simulator in order to identify the undisturbed condition of reservoir and resource assessment. Since Mount Iyang-Argopuro geothermal area is still in the exploration stage, the model created based on based on geological, geophysical, and geochemical data. The model has an area 14 km x 8.2 km and 9180 m in thickness. The model consists of 7410 of rectangular cell blocks with the roughest cell size is 1000 m x 1000 m and the finest is 200 m x 500 m. The model is verified by matching the model temperature and pressure profiles to the calculated geothermometer temperature and pressure, which shows good match enough.

Experimental Study of the Structural Behaviour of Reinforced Concrete Box Girder with the Using of Steel Plates Strengthening and Different Shapes of Cells

The aim of this research is to study the effect of using corrugated steel plate strengthening on the structural behaviour of reinforced concrete box girder by using corrugated steel plates with vertical and horizontal corrugation and studying the effect of the shape of cells by using rectangular and circular shape with the same web width and strengthening the circular cell with smooth plate. Five simply supported reinforced concrete box girders are casted by using Self-compacting concrete and experimentally tested under four-point load. The box girder specimens are divided into two groups according to the steel strengthening and the shape of cells. The experimental results showed that in the first group, the using of the vertical and horizontal corrugated steel plates strengthening increased the ultimate load by (7.14% and 11.03%) respectively compared with the control box girder, and decreased the crack width, the results also showed that in the second group, the using of circular cell and circular strengthened cell increased the ultimate load by (17.85% and 29.22%) respectively compared with the control box girder with rectangular cell and decreased the crack width. All the box girders in the first and second group failed with diagonal shear.

EXPERIMENTAL STUDIES ON THE INFLUENCE OF TRANSVERSE REINFORCEMENT FOR STRENGTH OF COMPRESSED REINFORCED CONCRETE ELEMENTS

The infl uence of transverse reinforcement, including indirect reinforcement, on the strength of compressed reinforced concrete elements is analyzed. This question arose in connection with the possibility of increasing the strength of short reinforced concrete elements loaded with a longitudinal force with small eccentricities within the section of the element. For such elements, the cage eff ect may appear, associated with the coeffi cient of transverse deformations, the magnitude of which is a direct factor in the destruction of the concrete sample, and the limitation of these directly aff ects the bearing capacity of the sample in the direction of increase. The infl uence of transverse reinforcement in the form of stirrups located with diff erent spacing, as well as indirect reinforcement in the form of meshes with a classical rectangular cell and meshes of the “zigzag” type is considered.

An Innovative Miniature Pulsating Emulsification Device: Flow Characterization and Measurement of Emulsion Stability

The aim of this study is the development of an emulsification device for two immiscible liquids with a total volume of approximately 3 mL. The heart of the device is a piston, with an aluminum plate fixed at its tip, which moves periodically up and down inside a rectangular cell. The plate geometry (uniform or non-uniform height) affects significantly both the emulsions stability and the size of the droplets of the prepared emulsions. Five parameters are examined during testing (surfactant type, surfactant concentration, proportion of immiscible liquids, piston stroke frequency, duration of emulsification) and all of them appear to have an important role in the resulting droplet size distribution. A macroscopic theoretical model is developed for the determination of the main hydrodynamic parameters of the innovative device. It is shown that the non-uniform height plate achieves higher shear rates when compared to the uniform height plate because of the smaller gap between the plate and the cell walls. However, the benefits of the higher shear rate are overturned by the larger effective breakage time encountered in the uniform height plate resulting from the larger surface area of its sides. The results of the emulsification experiments are analyzed using the parameter values derived by the developed model.

Variations in seed micromorphology and morphometry of native Indonesian Phalaenopsis and Paphiopedilum orchids

Hariyanto S. 2019. Variations in seed micromorphology and morphometry of native Indonesian Phalaenopsis and Paphiopedilum orchid. Biodiversitas 20: 3559-3567. Seeds of ten taxa of the genera Phalaenopsis and Paphiopedilum orchids were studied using light and scanning electron microscopy (SEM). Qualitative characters (seed and embryo shape, seed and embryo colour, ornamentation of testa cell, testa cell wall shape) as well as quantitative data (seed and embryo length, seed and embryo width, seed and embryo volume, seed length/seed width, embryo length/embryo width, seed volume/embryo volume and air space) were analysed. Seeds of all studied taxa were fusiform in shape and had smooth testa surfaces. Phalaenopsis testa cells were elongated with cylindrical cell walls, while Paphiopedilum testa cells were polygonal with thin and flat rectangular cell walls. The shape of the embryos was generally ovoid in Phalaenopsis and prolate in Paphiopedilum. Seed colors ranged from brown to dark brown. Embryo colors varied from light yellow, yellowish-brown, dark brown, black and white. Based on our investigation, there are variations in seed and embryo length, seed and embryo width, seed and embryo volume as well as the percentage of the air space, both in Phalaenopsis and Paphiopedilum. In general, the values of seed volume, embryo volume and air space in Paphiopedilum are higher than in Phalaenopsis. Together, the results of the study indicate that morphological and morphometric features can serve to identify live forms and distinguish between species.

Design and study on the tailorable directional thermal expansion of dual-material planar metamaterial

Current studies on tailoring the coefficient of thermal expansion of metamaterials focused on either complex bending-dominated lattice or the stretching-dominated lattice which transforms the spaces of triangle and tetrahedron. This paper proposes a kind of dual-material rectangular cell of tailorable thermal expansion, which reduces the complexities of design, calculation, and manufacture of lattice materials. The theoretical derivation using the matrix displacement method is adopted to study the thermal expansion properties of rectangular cell in the direction of height, the analytical expressions of coefficient of thermal expansion and optimization model are used to design the sizes of rectangular cell, and experimental verification is carried out. It is found that the middle cell of lattice had the same thermal expansion law as that of the unit cell. The rectangular cells of negative coefficient of thermal expansion −7 ppm/℃, zero coefficient of thermal expansion, and large positive coefficient of thermal expansion 36.2 ppm/℃ in the direction of height were realized, respectively. The consistency of theory, simulation, and experiment verifies that rectangular lattice material made of two kinds of common materials with a different coefficient of thermal expansions can achieve the design of coefficient of thermal expansion in the direction of height by choosing different material distribution and geometric parameters.