Selection of Preferred Floodplains for the Renaturalization of Hydrologic Functions: A Case Study of the Paraíba do Sul River Basin,Brazil

The primary goal of this study is to identify floodplains that are in large river basins and could potentially undergo renaturalization of their hydrologic functions. The study area is the Paraíba do Sul River Basin (55,400 km²), which is located in southeastern Brazil. The field work included the application of geoprocessing techniques (ArcGIS 10 and ENVI 4.7) for the delineation and individualization of the floodplain, and the following characteristics were surveyed: area, perimeter, circularity index and urbanization index. Discriminant and cluster analyses (SPSS 15) were performed, and 77 floodplains were found that exhibited a wide variation in area (0.13 to 1,540 km²) and perimeter (1.8 to 4,200 km), low circularity indices (<0.52), and a low average urbanization index (18.9 %). The floodplains were grouped according to how well the renaturalization of their hydrologic functions could be managed and categorized as follows: a) low management potential (9 units); b) medium management potential (15 units); and c) high management potential (52 units). The discriminant analysis correctly classified 100 % of the cases, which indicates that the model has a high predictive ability and can accurately classify the management potential of floodplains.     

重新定义设计的连接性

十年前,那些仅用于关键任务的应用和出现在科幻小说里的技术,现已成为众多消费类及工业应用不可或缺的部分。数字通信与计算能力正迅速扩展整个世界的连接性,并不断打破过去常规技术的界限。我们目前面临的设计挑战是如何以连接概念的前瞻性观念打造器件的智能性。     

Bronchospasm, a sign revealing pulmonary embolism

A papillary adenoma with malignant change consisting of only Paneth cells and their precursors is described. Neoplastic proliferation of Paneth cells is discussed from a point of view of cell biology.     

Functional analysis of three adjacent open reading frames from the right arm of yeast chromosome XVI

A 7·24 kb genomic DNA fragment from the yeast Saccharomyces cerevisiae chromosome XVI was isolated by complementation of a new temperature-sensitive mutation tsa1. We determined the nucleotide sequence of this fragment located on the right arm of chromosome XVI. Among the three, complete open reading frames: YPR041w, YPR042c and YPR043w contained within this fragment, the gene YPR041w was shown to complement the tsa1 mutation and to correspond to the TIF5 gene encoding an essential protein synthesis initiation translation factor. The YPR042c gene encodes a hypothetical protein of 1075 amino acids containing four putative transmembrane segments and is non-essential for growth. The gene YPR043c encoding the 10 kDa product, highly similar to the human protein L37a from the 60S ribosomal subunit, was found to be essential and a dominant lethal. We conclude that three tightly linked yeast genes are involved in the translation process. © 1998 John Wiley & Sons, Ltd.     

Initial stages of nucleation of molybdenum and tungsten carbide phases in tungstate–molybdate–carbonate melts

The electrochemical nucleation of Mo₂C and W₂C crystals for tungstate–molybdate–carbonate melts of specific compositions on Ag, Au, Cu, Pt, and Ni substrates was studied by the electrodeposition method. The influence of electrocrystallization conditions (temperature, deposition time, initial current pulse, and current density) was investigated. Experimental measurements indicate that crystallization overvoltage is associated with three-dimensional nucleation. Carbide deposition onto the substrates prepared from the same solid materials was not associated with crystallization overvoltage. The maximum value of the initial overvoltage, η_max, which includes crystallization and electrolysis overvoltages, is proportional to the electrode surface area. Under these conditions, surface diffusion limits the electrode process rate. An increase in carbide deposition rate leads to an increase in the number of crystallization centers. This reduces the duration of surface diffusion. A rise in the melt temperature complicates the crystallization process by alloy-formation phenomena. Overvoltage maximum height for metals, which do not form alloys, is proportional to the reciprocal of their formation time. Melt temperature increase promotes interdiffusion of refractory metal, carbon, and substrate, and also intensifies their chemical interaction. Structural mismatch is observed during molybdenum and tungsten carbide electrodeposition onto different single-crystal substrates.     

Enthalpies of formation of liquid and solid (gallium + palladium) alloys

The enthalpies of formation of liquid (Ga + Pd) alloys were determined by direct reaction calorimetry in the temperature range 1322 <T/K < 1761 and the molar fraction range 0 <x _Pd < 0.87. The enthalpies are very negative with a minimum Δ_mix H _m = −70.4 ± 3.0 kJ mol_-1 atx _Pd = 0.6, independent of the temperature. Limiting partial molar enthalpies of palladium and gallium were calculated as Δh _m (Ga liquid in ∞liquid Pd) = −265 ± 10 kJ mol₋₁ and Δh _m (Pd liquid in ∞liquid Ga) = -144 ± 5 kJ mol₋₁. The integral molar enthalpy is given by Δ_mix H _m =x(1-x) (-143.73 -232.47x + 985.77x ²-4457.8.x ³ + 6161.1x ⁴ + 2577.4x ⁵), wherex = x _Pd. Moreover, values for the enthalpies of formation and fusion of PdGa, Pd₂Ga, and the solid solution (withx _Pd = 0.8571) have been proposed. These results have been discussed taking into account the equilibrium phase diagram. Formerly Ph.D. student, Université de Provence     

The limiting molar partial enthalpies of mixing of iron, cobalt, nickel, palladium and platinum in liquid gallium and indium

Gallium and indium have been used as solvents for the determination of the molar partial enthalpy of mixing Δ_mixh_m^o(TM, Ga or In) (denoting liquid transition metal (TM) in infinite liquid gallium or indium) of the pure liquid transition metals Fe, Co, Ni, Pd and Pt by direct reaction calorimetry between 1000 K and 1500 K with the exception of Δ_mixh_m^o(Fe, In) (because of the shape of its equilibrium phase diagram). All the limiting enthalpies listed below refer to the liquid state. With pure gallium as solvent, they correspond to the reaction

TM(liq) − nGa(liq) → TM₁Ga_n(liq)

at the experimental temperature T_e, with n 1.

1. (i) Δ_mixh_m^o in gallium is found for Fe, Co, Ni, Pd and Pt to be −2, −44, −82, −144 and −155 kJ mol⁻¹.

2. (ii) Δ_mixh_m^o in indium is found for Co, Ni, Pd and Pt to be +28, −25, −127 and −114 kJ mol⁻¹.

In both solvents, these limiting enthalpies vary with a similar trend. This observation makes it possible to predict the limiting molar partial enthalpy Δ_mixh_m^o(Fe, In) of mixing of iron in indium as +70 kJ mol⁻¹. The results have been compared with the data proposed by Miedema and co-workers.     

Impact of Urbanization on the Hydrodynamics of a Water Table in a Floodplain with High Potential for Renaturation

Large river basins influence the development of human populations either by interfering with population growth or by providing a valuable resource that supports population growth. The Paraíba do Sul River catchment (55,400 km²) in southeastern Brazil supplies more than 14-million people with water, and is located in a region of Brazil with the highest Gross National Product (GNP). This catchment contains 77 floodplains (2156 km²) whose waters are highly regulated, and has a medium urbanization index (18.9%). Fifty-two of these floodplains (67.5%) have characteristics that make them suitable for the implementation of management practices that seek renaturation of the floodplain to ensure the sustainability of regional economic development. The floodplain examined in this study is highly managed and has a great potential for renaturation. We examined variations in groundwater level from the control section (lowest cross-section of the floodplain) to the propagation zone for flooding (9.43 km upstream) from January to December of 2013. The elevation of the water table near the structural control point had less seasonal oscillation than a distant area (p = 0.036). There was also a significant difference in the depth of the water table within the interior of the floodplain (urban area: 3.13 m, non-urban area: 0.49 m, p < 0.001). These results demonstrate that water regulation has been compromised in the study area due to the reduced connection between the river channel and floodplain in the urban region. Thus, land use in this floodplain has interfered with water storage capacity and the connectivity between sub-surface flows. These results suggest that this area is suitable for the implementation of techniques that seek renaturation of the floodplain, so that humans can continue to use this water and so that the effects of climatic changes can be mitigated.