Effect Of Light Level On Growth And Shoot Development Of Five Species Of Tropical Saplings.

Saplings of Acacia mangium, Shorea roxburghii, Dyera costulata, Eusideroxylon zwageri and Cinnamomum iners were grown at 4%, 7%, 25%, 50% and 100% relative light intensities (RLIs) and their growth was monitored by rate of increment of height and diameter, rate of production of new leaves and leaf life span. Leaves were analysed for their content of nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), calcium (Ca), chlorine (Cl), sulphur (S), boron (B), manganese (Mn), copper (Cu) and zinc ( Zn). For each RLI, two samples of leaves were taken for analysis: young fully expanded leaves and old about-to-shed leaves. From these analyses, the fate of nutrients was determined. Acacia mangium and Cinnamomum iners were found to grow best at 100% RLI, Shorea roxburghii at 50% RLI and, Dyera costulata and Eusideroxylon zwageri at 25% RLI. Acacia mangium at 100% RLI had the highest weekly height and diameter increment of 16.15 cm and 0.77 cm respectively. This is 4 times higher than the second best growth species, Shorea roxburghii at 50% RLI and 21 times higher than the slowest growth species, Eusideroxylon zwageri at 25% RLI. Acacia mangium at 100% RLI had the highest mean leaf production rate per week on leaders and branches, of 1.70 and 1.60 leaves respectively. This is 3 times higher than the second best species, Shorea roxburghii at 50% RLI and 17 times higher than the slowest growing species, Eusideroxylon zwageri at 25% RLI. At 100% RLI, Acacia mangium had the shortest average leaf life span, of 130 days on leaders and 124 days on branches. In general, average leaf life span increased with reduction in RLI for all species. A fast-growing plant is associated with higher height increment, higher diameter increment, higher mean leaf production and shorter leaf life span. The level of NPK for these species in this study shared a similar range with major agricultural crops in Malaysia. The highest rate of NPK incorporation (g per week) was found in Acacia mangium, followed by Dyera costulata, and it was relatively low for other species. The levels of NPK were higher in young leaves than the old leaves for all species at all RLIs. Dyera costulata seems to withdraw more than 60% of NPK and Shorea roxburghii more than 60% of P from old leaves before they shed. All species did not withdraw Mn and Zn

Investigation of the shape transferability of nanoscale multi-tip diamond tools in the diamond turning of nanostructures

In this article, the shape transferability of using nanoscale multi-tip diamond tools in the diamond turning for scale-up manufacturing of nanostructures has been demonstrated. Atomistic multi-tip diamond tool models were built with different tool geometries in terms of the difference in the tip cross-sectional shape, tip angle, and the feature of tool tip configuration, to determine their effect on the applied forces and the machined nano-groove geometries. The quality of machined nanostructures was characterized by the thickness of the deformed layers and the dimensional accuracy achieved. Simulation results show that diamond turning using nanoscale multi-tip tools offers tremendous shape transferability in machining nanostructures. Both periodic and non-periodic nano-grooves with different cross-sectional shapes can be successfully fabricated using the multi-tip tools. A hypothesis of minimum designed ratio of tool tip distance to tip base width (L/Wf) of the nanoscale multi-tip diamond tool for the high precision machining of nanostructures was proposed based on the analytical study of the quality of the nanostructures fabricated using different types of the multi-tip tools. Nanometric cutting trials using nanoscale multi-tip diamond tools (different in L/Wf) fabricated by focused ion beam (FIB) were then conducted to verify the hypothesis. The investigations done in this work imply the potential of using the nanoscale multi-tip diamond tool for the deterministic fabrication of period and non-periodic nanostructures, which opens up the feasibility of using the process as a versatile manufacturing technique in nanotechnology

PAK6: a potential anti-cancer target

p21-activated kinase 6 (PAK6) is a member of the PAK family of serine/threonine kinases that are known effectors of Rho GTPases Cdc42 and Rac. PAKs regulate a large number of complex cellular mechanisms, including cell motility, morphology, and tumor development. PAK6, initially cloned as an interacting partner of the androgen receptor (AR), is associated with an array of cellular processes implicated in tumor progression. However, the full biological implications of PAK6 activity during cancer remain poorly understood. In this review, we assess our current understanding of the physiological roles of classical PAK6 functionality in mammals, in addition to its emerging role in tumorigenesis

Mycelial growth and germanium uptake by four species of ganoderma

Four Ganoderma species (G. tsugae, G. subamboinense var. laevisporium, A TCC 52419, G. tropicum and G. lucidum) were incubated in liquid medium containing different concentrations of germanium (Ge) for up to 20 days at 28 C. Increasing the Ge concentration of the medium resulted in a gradual decrease in the growth of the fungal mycelium. However, the Ge content in the mycelium increased with increasing Ge concentration. Different species recorded different levels of tolerance towards the Ge. In each case, the optimum concentration of the incorporated Ge in the medium was established as 100 mg/l for both optimal uptake of Ge by the fungal mycelium and optimal mycelial growth

Magnetostratigraphy of the Lower Triassic beds from Chaohu(China) and its implications for the Induan–Olenekian stage boundary.

A magnetostratigraphic study was performed on the lower 44 m of the West Pingdingshan section near Chaohu city, (Anhui province, China) in order to provide a magnetic polarity scale for the early Triassic. Data from 295 paleomagnetic samples is integrated with a detailed biostratigraphy and lithostratigraphy. The tilt-corrected mean direction from the West Pingdingshan section, passes the reversal and fold tests. The overall mean direction after tilt correction is D=299.9º, I=18.3º (κ=305.2, α95=1.9, N=19). The inferred paleolatitude of the sampling sites (31.6ºN, 117.8ºE) is about 9.4º, consistent with the stable South China block (SCB), though the declinations indicate some 101o counter-clockwise rotations with respect to the stable SCB since the Early Triassic. Low-field anisotropy of magnetic susceptibility indicates evidence of weak strain. The lower part of the Yinkeng Formation is dominated by reversed polarity, with four normal polarity magnetozones (WP2n to WP5n), with evidence of some thinner (<0.5 m thick) normal magnetozones. The continuous magnetostratigraphy from the Yinkeng Formation, provides additional high-resolution details of the polarity pattern through the later parts of the Induan into the lowest Olenekian. The magnetostratigraphic and biostratigraphic data shows the conodont marker for the base of the Olenekian (first presence of Neospathodus waageni) is shortly prior to the base of normal magnetozone WP5n. This provides a secondary marker for mapping the base of the Olenekian into successions without conodonts. This section provides the only well-integrated study from a Tethyan section across this boundary, but problems remain in definitively relating this boundary into Boreal sections with magnetostratigraphy

PIEKF-VIWO: Visual-Inertial-Wheel Odometry using Partial Invariant Extended Kalman Filter

Invariant Extended Kalman Filter (IEKF) has been successfully applied in Visual-inertial Odometry (VIO) as an advanced achievement of Kalman filter, showing great potential in sensor fusion. In this paper, we propose partial IEKF (PIEKF), which only incorporates rotation-velocity state into the Lie group structure and apply it for Visual-Inertial-Wheel Odometry (VIWO) to improve positioning accuracy and consistency. Specifically, we derive the rotation-velocity measurement model, which combines wheel measurements with kinematic constraints. The model circumvents the wheel odometer's 3D integration and covariance propagation, which is essential for filter consistency. And a plane constraint is also introduced to enhance the position accuracy. A dynamic outlier detection method is adopted, leveraging the velocity state output. Through the simulation and real-world test, we validate the effectiveness of our approach, which outperforms the standard Multi-State Constraint Kalman Filter (MSCKF) based VIWO in consistency and accuracy