Feminism and Social Theory in Geography: An Introduction*   总被引：1，自引：0，他引：1  

Karen Dias  Jennifer Blecha 《The Professional geographer》2007,59(1):1-9

This essay introduces a collection of articles based on papers developed for a Fall 2004 speaker series at the University of Minnesota. The articles address the continued relevance of feminist geography and the unique contributions of feminist perspectives in various areas of geographic research. They also point out directions for needed future research. This introduction briefly reviews the successes of and remaining challenges to feminist geography, including material inequities yet unresolved in two other (nonresearch) “places” of academic life: teaching and the workplace. We discuss the ongoing underrepresentation of women and people of color on our faculties and in the front of classrooms.  相似文献   

A study of the sea level and current effects on the sea state in Galway Bay,using the numerical model COAWST     

Calvino  Cl&#;ment  Dabrowski  Tomasz  Dias  Fr&#;d&#;ric 《Ocean Dynamics》2022,72(11):761-774

A coupled wave and ocean model is applied to the region of Galway Bay in the west of Ireland, using the numerical modelling suite COAWST. The coupled model was validated in a previous study. Here we focus on the impact of the currents and sea level on the sea state during Storm Hector (2018/06/14). The purpose of the research is to improve the wave dynamics knowledge specifically in Galway Bay by highlighting and quantifying the dominant current-induced mechanisms on the sea state observed numerically. We want to know where wave-current interaction is modifying the sea state in the bay, and if the change is significant to justify the use of a coupled model for an operational application. We show that the impacts of the tidal sea surface height on bottom friction and of the current-induced refraction on the spatial distribution of the waves are the dominant mechanisms. Those two effects are well-documented and observed in the literature already. A strong feedback impact of the coupling is also put into evidence. The wave-induced response in terms of currents leads to a noticeable variation in terms of wave height. Less documented in the literature, we discuss the link between current-induced refraction and the reduction of wave generation by wind.

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Mantle-like Sr–Nd isotope composition of Fe–K subalkaline granites: the Peneda–Gerês Variscan massif (NW Iberian Peninsula)     

A. C. Mendes  G. Dias 《地学学报》2004,16(3):109-115

The Peneda–Gerês massif is one of the most representative NW Iberian late‐ to post‐orogenic Variscan granitic plutons. It resulted essentially from the subsynchronous emplacement, at 290–296 Ma, of two granitic magmas of Fe–K subalkaline affinity, with primitive isotopic composition: Sr_i = 0.703–0.707 and εNd_i=?1.5 to ?2.4. An origin by mantle input followed by mantle–crust interactions is proposed, implying the contribution of a less enriched mantle component than that involved in the genesis of synorogenic hybrid granitoids of Mg–K subalkaline affinity. A less voluminous aluminopotassic and isotopically more evolved magma (Sr_i=0.708–0.709 and εNd_i=?3.5 to ?3.9) with little or no mantle input was also generated, suggesting the involvement of lower crust materials. Therefore, this study suggests an input of juvenile magmas in late Variscan times, the mantle‐like isotope signature of Fe–K granitic magmatism being clearly related to a geodynamic setting of extensional processes, large‐scale uplift and thinning.  相似文献   

The convective boundary layer over pasture and forest in Amazonia   总被引：1，自引：0，他引：1  

G. Fisch  J. Tota  L. A. T. Machado  M. A. F. Silva Dias  R. F. da F. Lyra  C. A. Nobre  A. J. Dolman  J. H. C. Gash 《Theoretical and Applied Climatology》2004,78(1-3):47-59

Summary The coupling between different types of surface (tropical forest or grass) and the Convective Boundary Layer (CBL) has been investigated using observational (rawinsoundings) data collected over Rondônia in southwest Amazonia. The data reported here support the notion that deforestation may modify the dynamics of the boundary layer, in particular during the dry season. In this period the sensible heat fluxes are very high over pasture, creating a CBL around 550m deeper compared to that over the forest. The measurements showed the height of the fully developed CBL for pasture to be 1650m, compared to around 1100m for forest. During the wet season the height of the CBL is lower than during the dry season and has the same height (around 1000m) for forest and pasture sites. The CBL over pasture is hotter and drier than over forest during the dry season, but during the wet season the air temperatures and humidities are similar. Comparing the CBL growth during the dry and wet season, there is evidence that the CBL properties over the forest are not dependent on the surface characteristics, but over the pasture they are.  相似文献   

Clay minerals from the sedimentary cover from the Northwest Iberian shelf     

A. Oliveira  F. Rocha  A. Rodrigues  J. Jouanneau  A. Dias  O. Weber  C. Gomes 《Progress in Oceanography》2002,52(2-4)

The Northern Iberian margin is a typical example of a continental margin subjected to seasonal highly energetic regime (waves and tides) and receiving inputs of continental sediments via riverine discharges. The principal goal of this study has been to use clay minerals as indicators of sedimentary dynamics in the open shelf system. The distributions of clay mineral in the top layer of the sedimentary cover are shown to be related to their continental sources, but also reflect the influences of winter storms and longshore currents in determining the pathways of sediment transport.The mineralogical composition of the material issuing from the rivers is very similar to the general mineralogical composition of the fine fractions of the seabed sediments. Those deposits that are directly influenced by riverine discharges have higher contents of kaolinite (>20%), whereas those that are not have higher contents of illite (>80%). The available data indicate no significant quantities of terrigenous particles are being discharged from the Spanish rias. Therefore, we conclude that physical processes are controlling the clay mineral distributions and that, despite contributions from the Minho River, the main source of fine detrital particles to the shelf region is the Douro River discharge. These particles settle on the middle shelf, below the 60 m isobath. During storm events these particles are re-suspended and advected northwards to the Galician shelf or into deeper domains. Thus the distributions of the clays indicate there is a net transport of fine sediments both northwards and off-shelf.  相似文献   

Metals in eggs and hatchlings of Dermochelys coriacea (testudines) in Espírito Santo,Brazil and their relation to hatching and emergence success     

Jordana Borini Freire  Rafael M. Sousa  Karla Taufner  Maria TW Carneiro  Henrique R Filgueiras  Dominik Lenz  Paulo Dias Ferreira  Denise C Endringer 《Marine Ecology》2021,42(1):e12633

Certain concentration of metal may influence survival in embryonic stages, reducing the birthrate and hatching emergence. This study aimed to evaluate concentration of metal in eggs and hatchlings of Dermochelys coriacea and correlate metal concentrations in eggs with hatching and emergence success. The samples were collected at Biological Reserve Station, ES, Brazil. At the nests' opening, unhatched eggs and stillborn hatchlings were collected to survey the successful hatching and emergence of D. coriacea. The eggs shell, egg content, and dead hatchlings metal concentrations were compared to hatching and emergence success. A positive correlation was found between the concentration of copper (Cu) in the hatchlings and the success of the emergence (r² = .28, p < .05), and a moderate positive correlation between the concentrations of iron (Fe) and barium (Ba; r² = .44, p < .05) and success hatching. The concentrations of metals in eggs and hatchlings of D. coriacea in the Espírito Santo are below the levels that could be considered harmful to the species. In summary, there is a positive correlation between metals levels and hatching and emergence success.  相似文献   

A sequential sparse polynomial chaos expansion using Bayesian regression for geotechnical reliability estimations     

Qiujing Pan  Xingru Qu  Leilei Liu  Daniel Dias 《国际地质力学数值与分析法杂志》2020,44(6):874-889

Polynomial chaos expansions (PCEs) have been widely employed to estimate failure probabilities in geotechnical engineering. However, PCEs suffer from two deficiencies: (a) PCE coefficients are solved by the least-square minimization method which easily causes overfitting issues; (b) building a high order PCE is often computationally expensive. In order to overcome the aforementioned drawbacks, the Bayesian regression technique is employed to evaluate PCE coefficients, which not only provides a sparse solution but also avoids overfitting. With the aid of the predictive means and variances given by Bayesian analysis, a learning function is proposed to sequentially select the most informative samples that are critical to build a PCE. This sequential learning scheme can highly enhance the computational efficiency of PCEs. Besides, importance sampling (IS) is incorporated into the sequential learning (SL)-PCEs to deal with geotechnical problems with small failure probabilities. The proposed method of SL-PCE-IS is applied to three illustrative examples, which shows that the improved PCE method is more effective and efficient than the common PCEs method, leading to accurate estimations of small failure probabilities using fewer training samples.  相似文献   

Factors governing abundance of hydrolyzable amino acids in the sediments from the N.W. European Continental Margin (47–50°N)     

T. Boski  J. Pessoa  P. Pedro  J. Thorez  J. M. A. Dias  I. R. Hall 《Progress in Oceanography》1998,42(1-4)

Fifty-six samples representing 6 sediment cores taken along the N.W. European Continental Margin from the shelf, slope and abyssal plain of the Goban Spur and Meriadzek Terrace were quantitatively analysed for total hydrolyzable amino acids (THAA) and clay minerals. In descending order, the five most abundant amino acids making up more than 70% of the total were: aspartic acid, glycine, serine, alanine and glutamic acid. Clay mineral proportions were typical for the N.E. Atlantic, in order of descending abundance: illite, kaolinite, chlorite, smectite and mixed layers.The Meriadzek Terrace area is characterised by fine grain suspension sedimentation with a low pelagic carbonate input and the lowest content of THAA. In contrast, the Goban Spur transect is characterised by much higher carbonate inputs and more vigorous hydrodynamics as judged from granulometry and the high abundance of minerals of shelf and continental origin and a generally higher THAA content. The pelagic portion of THAA deposited at the sea floor is more readily mineralised during early diagenesis than the more ‘refractory', clay mineral-associated continental portion. Along this margin the average mineralization of THAA down to 25 cm in the sediment is about 54%. There is a significant affinity between chlorites and amino acids which we suggest may involve the formation of ionic bonds between the octahedral layers of the clay and the amino acids.  相似文献   

Extrusion movements of a tunnel head reinforced by finite length bolts—a closed‐form solution using homogenization approach     

Henry Wong  Didier Subrin  Daniel Dias 《国际地质力学数值与分析法杂志》2000,24(6):533-565

An analytical model on the general behaviour of a tunnel head, reinforced by finite length bolts is proposed. This model is based on the homogenization method and spherical symmetry assumption. Despite its simplicity, and in consequence its limits of validity, it does allow a quick estimation of the key design parameters: frontal displacement, extension of decompressed zone, ground stresses and bolt tension, and constitutes thereby a very useful and handy tool for design engineers. In particular, the influence of the reinforcement length, as well as other important design parameters, are studied by the proposed model. The charts resulting from the parametric studies are directly applicable. Otherwise, the comparison to a 3D numerical model is also presented in this paper. The first results provide the validation of the analytical solution, at least in terms of average extrusion movements. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

Predatory pelagic fishes of the Bijagós Archipelago (Guinea-Bissau) show high overlap in diets dominated by sardinella     

E Correia  JP Granadeiro  A Regalla  E Dias  A Almeida  P Catry 《African Journal of Marine Science》2017,39(4):389-396

Knowledge of trophic interactions between the key components of marine communities is required to understand food-web dynamics and develop ecosystem-based management approaches. In West Africa, where fisheries sustain the livelihoods of a significant part of the human population, this understanding is even more urgent, especially in the face of rapidly expanding fisheries and some stock collapses in the region. We studied the feeding ecology of the Crevalle jack Caranx hippos, West African Spanish mackerel Scomberomorus tritor and Guinean barracuda Sphyraena afra in the Bijagós Archipelago, Guinea-Bissau. These are the most abundant pelagic predatory teleost fishes in the area, but little is known about their ecology despite being species with commercial and recreational value, and they likely also play an important role in various African coastal ecosystems. Our findings show a high degree of dietary overlap among these three predator species, despite some degree of segregation by prey size and type. All three predators depend on Sardinella maderensis as the most important prey, which together with other members of the Clupeidae represented 47–96% of the ingested prey items. There was little difference in the diets of the predators between the dry and rainy seasons. These novel findings suggest a ‘wasp-waist’-structured ecosystem in the Bijagós Archipelago in which S. maderensis is the central small-sized pelagic fish species, and stress the need for an ecosystem-based approach to fisheries management in the region, with precautionary measures taken to avoid the overexploitation of clupeids.  相似文献