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Vegetation was sampled in 86 plots of riparian forest and dry forests of northern Togo. The recorded data were subjected to floristic and quantitative ecological analyses in order to describe the main woody plant communities and their size structure. The plant groupings were determined by detrended correspondence analysis (DCA) and defined through the indicator value method. Alpha diversity index, and tree species structure features were computed for forest woody plant groupings. Results classified four woody communities. Two of them belonged to riparian forest while the other two, dry forest. A total of 77 plant species consisted of woody species. Pterocarpus santalinoïdes and Anogeissus leiocarpus were the most important species based on their indicator values. The diversity indices of P. santalinoïdes, Eugenia kerstingii and A. leiocarpus and Vitellaria paradoxa plant communities were significant and indicated a wide distribution of species in the area, while their structural features relected those of forests characteristic of the Sudanian climatic zones. In general, the natural regeneration rate among the plant groupings was satisfactory and quiet similar to those found in previous works in this region. [ABSTRACT FROM AUTHOR]

Based upon 14 field surveys conducted between 2003 and 2008, we showed that the seasonal pattern of sea surface partial pressure of CO2 (pCO2) and sea-air CO2 fluxes differed among four different physical-biogeochemical domains in the South China Sea (SCS) proper. The four domains were located between 7 and 23° N and 110 and 121° E, covering a surface area of 1344x10³ km² and accounting for ~54% of the SCS proper. In the area off the Pearl River estuary, relatively low pCO2 values of 320 to 390 µatm were observed in all four seasons and both the biological productivity and CO2 uptake were enhanced in summer in the Pearl River plume waters. In the northern SCS slope/basin area, a typical seasonal cycle of relatively high pCO2 in the warm seasons and relatively low pCO2 in the cold seasons was revealed. In the central/southern SCS area, moderately high sea surface pCO2 values of 360 to 425 µatm were observed throughout the year. In the area west of the Luzon Strait, a major exchange pathway between the SCS and the Pacific Ocean, pCO2 was particularly dynamic in winter, when northeast monsoon induced upwelling events and strong outgassing of CO2. These episodic events might have dominated the annual sea-air CO2 flux in this particular area. The estimate of annual sea-air CO2 fluxes showed that most areas of the SCS proper served as weak to moderate sources of the atmospheric CO2, with sea-air CO2 flux values of 0.46±0.43molm-2 yr-1 in the northern SCS slope/basin, 1.37±0.55molm-2 yr-1 in the central/southern SCS, and 1.21±1.48molm-2 yr-1 in the area west of the Luzon Strait. However, the annual sea-air CO2 exchange was nearly in equilibrium (-0.44±0.65molm-2 yr-1) in the area off the Pearl River estuary. Overall the four domains contributed (18±10)x1012 g Cyr-1 to the atmospheric CO2. [ABSTRACT FROM AUTHOR]

The objective of this study was to obtain an optimum formulation for microencapsulating venlafaxine hydrochloride ion-exchange resins. This was achieved by investigating various factors which influenced the drug release. The percentage of drug released was used as an index to investigate the individual factor. The optimum coating formulation was acquired by orthogonal experiments in which the concentration of coating material in acetone was 3%, the ratio of drug-resin complexes to coating materials was 8:1 and the ratio of plasticity-agent to coating material was 5%. The results indicated that the use of ion-exchange resins along with a suitable coating material would be a feasible way to prepare a marked prolonged release type of microcapsules by the emulsion solvent diffusion method. [ABSTRACT FROM AUTHOR]

Summary.  The calmodulin (CaM) localization pattern in the growing hyphal tip of Aspergillus nidulans was studied with the functional GFP::CaM fusion protein. A faint tip-high gradient of CaM was found in the growing hyphal tip, with CaM highly localized in the region corresponding to the Spitzenkörper forming a bright granule. The position of highly concentrated CaM in the extreme apex seemed to determine the orientation of the hypha. The normal pattern of CaM localization was also shown to be dependent on the integrated actin cytoskeleton. When the growth of the hyphal tip ceased, CaM failed to localize in the bright granule and was evenly distributed in the hyphal tip. These findings suggest that CaM may play an important role in establishing and maintaining apical organization, morphogenesis, and growth in Aspergillus nidulans. [ABSTRACT FROM AUTHOR]

The parametrically excited lateral vibration of a mass-loaded string is investigated in this paper. Supposing that the mass at the lower end of the string is subjected to a vertical harmonic excitation and neglecting the higher-order vibration modes, the equation of motion for the mass-loaded string can be represented by a Mathieu's equation with cubic nonlinearity. Based on the stability criterion for Mathieu's equation, the critical conditions inducing parametric resonance are clarified. Theoretical analysis shows that when the natural frequency fs of the string lateral vibration and the vertical excitation frequency f satisfy fs = (n/2)f, n = 1, 2, 3, …, parametric resonance occurs in the case of no damping. For a damped system, parametric resonance most likely occurs when f is close to 2fs, and depends on the damping of the system and the vertical excitation. The critical excitation has been derived at different frequencies. If the natural frequency of the mass vertical vibration happens to be twice that of the string lateral vibration, the parametric resonance may occur due to a small disturbance. Numerical simulations show that the lateral vibration of the string does not increase infinitely at parametric resonance because the parametric excitation is self-tuned due to the coupling between the vertical and lateral vibrations. Finally, the theoretical results are supported by some experimental work. [ABSTRACT FROM AUTHOR]

Atomic layers of GaP and InP binary compounds with unique anisotropic structural, electronic and mechanical properties have been predicted from first-principle molecular dynamics simulations. These new members of the phosphide binary compound family stabilize to a sandwiched two-dimensional (2D) crystalline structure with orthorhombic lattice symmetry and high buckling of 2.14 Å–2.46 Å. Their vibration modes are similar to those of phosphorene with six Raman active modes ranging from ∼80 cm−1 to 400 cm−1. The speeds of sound in their phonon dispersions reflect anisotropy in their elastic constants, which was further confirmed by their strong directional dependence of Young’s moduli and effective nonlinear elastic moduli. They show wide bandgap semiconductor behavior with fundamental bandgaps of 2.89 eV for GaP and 2.59 eV for InP, respectively, even wider than their bulk counterparts. Such bandgaps were found to be tunable under strain. In particular, a direct–indirect bandgap transition was found under certain strains along zigzag or biaxial orientations, reflecting their promising applications in strain-induced bandgap engineering in nanoelectronics and photovoltaics. Feasible pathways to realize these novel 2D phosphide compounds are also proposed. [ABSTRACT FROM AUTHOR]

Although computational power is increasingly available, high-fidelity simulation based aerodynamic shape optimization is still challenging for industrial applications. To make the simulation based optimization acceptable in the practice of engineering design, a technique combining mesh morphing and reduced order modeling is proposed for efficient aerodynamic optimization based on CFD simulations. The former technique avoids the time-consuming procedure of geometry discretization. And the latter speeds up the procedure of field solution by combining pre-computed solution snapshots. To test the efficiency of the proposed method, the windshield of a motorbike is analyzed and optimized. It is shown that even the total number of cells of the mesh is around 0.4 million, the CFD computation and the post processing of the results can be completed in less than 10 seconds if the reduced order model is adopted. Running on a personal computer, the generic algorithm is applied to optimize the profile of the windshield. A 8% reduction of the drag coefficient is achieved after 800 queries of the reduced order CFD model and the total CPU time is only around 2 hours.

Based upon 14 field surveys conducted between 2003 and 2008, we showed that the seasonal pattern of sea surface partial pressure of CO2 (pCO2) and sea–air CO2 fluxes differed among four different physical–biogeochemical domains in the South China Sea (SCS) proper. The four domains were located between 7 and 23° N and 110 and 121° E, covering a surface area of 1344 × 103 km2 and accounting for ~ 54% of the SCS proper. In the area off the Pearl River estuary, relatively low pCO2 values of 320 to 390 μatm were observed in all four seasons and both the biological productivity and CO2 uptake were enhanced in summer in the Pearl River plume waters. In the northern SCS slope/basin area, a typical seasonal cycle of relatively high pCO2 in the warm seasons and relatively low pCO2 in the cold seasons was revealed. In the central/southern SCS area, moderately high sea surface pCO2 values of 360 to 425 μatm were observed throughout the year. In the area west of the Luzon Strait, a major exchange pathway between the SCS and the Pacific Ocean, pCO2 was particularly dynamic in winter, when northeast monsoon induced upwelling events and strong outgassing of CO2. These episodic events might have dominated the annual sea–air CO2 flux in this particular area. The estimate of annual sea–air CO2 fluxes showed that most areas of the SCS proper served as weak to moderate sources of the atmospheric CO2, with sea–air CO2 flux values of 0.46 ± 0.43 mol m−2 yr−1 in the northern SCS slope/basin, 1.37 ± 0.55 mol m−2 yr−1 in the central/southern SCS, and 1.21 ± 1.48 mol m−2 yr−1 in the area west of the Luzon Strait. However, the annual sea–air CO2 exchange was nearly in equilibrium (−0.44 ± 0.65 mol m−2 yr−1) in the area off the Pearl River estuary. Overall the four domains contributed (18 ± 10) × 1012 g C yr−1 to the atmospheric CO2.