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71.
Zaire Z. Dinzey‐Flores 《Singapore journal of tropical geography》2012,33(2):198-211
In 1992, Puerto Rico's governor and police superintendent incorporated the National Guard with local police in a militarized battle against crime. Mano dura contra el crimen (strong arm/iron fist against crime) policies led to the gating of 82 public housing communities in the island. Simultaneously, privileged private communities organized and petitioned municipalities to retrofit their neighbourhoods with gates in the name of safety. These enclosures followed the privatized management of all public housing communities in the island only a few years before. Based on ethnographic research, I examine the sociospatial outcomes of these policies, how they reframe community participation and deploy a discourse of self‐responsibility that distributes power unequally across private and public housing communities. While in the privileged communities these policies have cultivated community leaders and invigorated social life as residents take control over public space, the gates in the communities of the poor reflect a skeletal structure of democracy. Private management companies impose increasingly restrictive regulations in attempts to organize the community and the only recourse to participation is to engage in small acts of everyday resistance, from apathy to subversion. As part of larger neoliberal tendencies to retrench the ‘public’ in favour of the ‘private’, the mano dura policies curtail democracy as the voices of the poor are silenced and the scope of efficacy of the rich expands. 相似文献
72.
Escudero Christian R. Ramirez Gaytan Alejandro Zamora Camacho Araceli Preciado Adolfo Flores Karen L. Gomez Hernandez Adan 《Natural Hazards》2022,110(1):247-267
Natural Hazards - We performed a seismic vulnerability assessment that involves geotechnical and building structure analysis for Puerto Vallarta, Mexico, a city located along the pacific coast.... 相似文献
73.
Flores Avils Gabriela Patricia Spadini Lorenzo Sacchi Elisa Rossier Yvan Savarino Joel Ramos Oswaldo Eduardo Duwig Cline 《Hydrogeology Journal》2022,30(1):181-201
Hydrogeology Journal - A hydrogeochemical and stable isotopic ( $${\updelta }^{15}{\mathrm{N}}_{{\mathrm{NO}}_{3}}$$ and $${\updelta }^{18}{\mathrm{O}}_{{\mathrm{NO}}_{3}}$$ ) multitracer approach... 相似文献
74.
75.
Pedro Correia J. Brendan Murphy Artur A. S Rúben Domingos Deolinda Flores 《Geological Journal》2013,48(1):101-107
The first occurrence of arachnids (Aphantomartus pustulatus) in the Carboniferous strata of Portugal is documented and its palaeobiogeographic significance is assessed. The Aphantomartidae species are thought to be native to Central Europe where its oldest example is recorded in Middle–Upper Mississippian strata. Known occurrences are preserved along the flanks of mountains such as the Appalachian Mountains, the Cantabrian Mountains and the Valongo Anticline (Portugal, Iberian Massif) and provide clear evidence that the Aphantomartidae species probably lived in upland or mountainous environments. The Iberian Massif may have served as a ‘link’ between the migration routes of several terrestrial animals from North America and Eurasia, and this linkage constrains the palaeogeographic and palaeoenvironmental conditions in equatorial Pangaea during the Carboniferous and Early Permian. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
76.
H. Flores P. Goldoni F. Royer S. Piranomonte S.D. Vergani F. Onori E. Palazzi S. Covino S. Randich F. Hammer E. Pian S. Savaglio G. Tagliaferri 《Astronomische Nachrichten》2011,332(3):288-291
Using the integral field unit of X‐shooter at VLT, we have recovered the first velocity fields of GRB host galaxies at redshift <0.6. This facility is able to recover not only the velocity fields from almost all emission lines thanks to an unrivaled wavelength coverage, but also to recover maps of physical properties. We present the preliminary analysis of X‐shooter/IFU observations dedicated to the study of GRB host galaxies undertaken in the frame of the Italian‐French GTO program. Our goal is to understand the physical processes at the origin of the GRB by analyzing in detail the spatial distributions of the kinematics, metallicities, extinction, star‐formation, and how they are inter‐related (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
77.
Miguel Cortés Sánchez Francisco J. Jiménez Espejo María D. Simón Vallejo Juan F. Gibaja Bao António Faustino Carvalho Francisca Martinez-Ruiz Marta Rodrigo Gamiz José-Abel Flores Adina Paytan José A. López Sáez Leonor Peña-Chocarro José S. Carrión Arturo Morales Muñiz Eufrasia Roselló Izquierdo José A. Riquelme Cantal Rebecca M. Dean Emília Salgueiro Rafael M. Martínez Sánchez Nuno F. Bicho 《Quaternary Research》2012,77(2):221-234
New data and a review of historiographic information from Neolithic sites of the Malaga and Algarve coasts (southern Iberian Peninsula) and from the Maghreb (North Africa) reveal the existence of a Neolithic settlement at least from 7.5 cal ka BP. The agricultural and pastoralist food producing economy of that population rapidly replaced the coastal economies of the Mesolithic populations. The timing of this population and economic turnover coincided with major changes in the continental and marine ecosystems, including upwelling intensity, sea-level changes and increased aridity in the Sahara and along the Iberian coast. These changes likely impacted the subsistence strategies of the Mesolithic populations along the Iberian seascapes and resulted in abandonments manifested as sedimentary hiatuses in some areas during the Mesolithic–Neolithic transition. The rapid expansion and area of dispersal of the early Neolithic traits suggest the use of marine technology. Different evidences for a Maghrebian origin for the first colonists have been summarized. The recognition of an early North-African Neolithic influence in Southern Iberia and the Maghreb is vital for understanding the appearance and development of the Neolithic in Western Europe. Our review suggests links between climate change, resource allocation, and population turnover. 相似文献
78.
We investigated the effects of soil water potential (SWP) and temperature on seed germination of six coexisting species of an inter-tropical desert. These species include three life-forms; the shrubs Cercidium praecox andProsopis laevigata ; the columnar succulents Neobuxbaumia tetetzo and Pachycereus hollianus; and the arborescent semi-succulents Beaucarnea gracilis and Yucca periculosa. In the six species germinability increased and germination time and speed of germination (t50) decreased as SWP decreased. The SWP treatments were 0 MPa, −0·12 MPa, −0·2 MPa, −0·41 MPa and −0·66 MPa. There was, however, a SWP threshold below which germination time and t50increased and germinability decreased. The shrubs had the highest germinability whereas the columnar succulents had the lowest. The shrubs also had shorter germination time andt50 than arborescent semi-succulents whereas seeds of the columnar succulents were indeterminate. In all species except P. laevigata germinability increased and the germination time and t50decreased as temperature increased. The temperature treatments were 12°C, 20°C and 26°C. The shrubs had the shortest t50and germination time and the highest germinability at all temperatures. Arborescent semi-succulents had the lowest germinability and longest germination time and t50at the three temperatures treatments. Our results support the hypothesis that in desert environments different plant life-forms utilise different germination strategies to persist. 相似文献
79.
—?Induced microseismicity data from a large volume fluid injection into sedimentary rock was analyzed to study the fracture system, fluid pathways, and state of stress in the lower Frio formation in east Texas. Seismicity data are from two arrays of 25 3-component geophone packages sited in two monitoring boreholes. From a total of 2,894 event triggers, a subset of 54 microearthquakes was chosen for their high quality seismograms and clear P and S arrivals. Arrival times were picked with a precision of 0.5 to 1.0?ms, and microearthquakes were located with hypocentral uncertainties estimated as less than 10–20?m. Hypocenters farthest from the injection well define a nearly horizontal tube of seismicity approximately aligned in the direction of the injection well. A simultaneous inversion of arrival times for transverse isotropic velocity structure and hypocenters yielded P-wave anisotropy of ?14% and S-wave anisotropy of ?2%. Thus, velocities along vertical ray paths are higher than those along horizontal paths, probably because of lithologic differences. Single-event focal mechanisms were determined for 47 events, and many of them are normal fault type. The minimum principal stress derived from the focal mechanisms is nearly horizontal and trends approximately north-south, consistent with the regional stress state. An imaging analysis of the seismograms shows the presence of strong seismic scatterers at positions that correlate with boundaries seen in the hypocenters; both features probably result from a similar set of heterogeneities. This study demonstrates the abundance of information that can be extracted from induced seismicity data and underscores the value of induced seismicity monitoring for studying the fluid and fracture systems created by fluid injections. 相似文献
80.
The Rio Maior Basin (Portugal) is a tectonic depression, filled by a Pliocene sequence that comprises, from floor to roof: (i) kaoliniferous fine sands, (ii) diatomites and lignites, (iii) recent deposits of sandstone and clay. The diatomites and lignites form a small dissimetric syncline with alternating seams. Ten lignite seams were identified and named from floor to roof as F, E, D, C.2, C.1, C, B, A, a and a′. Seams A, D, E and F are considered to be the main seams.The organic fraction consists mainly of macerals of the huminite group, with small percentages of inertinite and liptinite groups. However, the petrographic composition of each seam is distinct, particularly with regards to macerals of the huminite and liptinite groups.Calculation of petrographic indices permitted to plot the coals in facies and palaeoenvironment diagrams. Five facies have been defined: (i) aquatic, (ii) herbaceous swamp, (iii) mixed swamp with forest and herbaceous vegetation, (vi) forest swamp (wetter) and (v) forest swamp (drier).These lignites are humic coals formed from organic matter of terrestrial origin. The peat biomass at the origin of these coals formed from a very diverse vegetation comprising gymnosperms and angiosperms. In seams F, and occasionally in seams E and D, Botryococcus algae have also contributed to the biomass. Peat deposition corresponded to a rheotrophic hydrological regime: the water level always remained above the topographic surface of the basin. Nevertheless, during the deposition of seam A in the northern part of the basin, the water level was slightly below the topographic surface. The organic matter was preserved in anaeorobic conditions. 相似文献