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11.
A lack of clear political commitment together with confusing rules and enforcement often characterize the institutional context of policy implementation and regulatory compliance in developing countries. By connecting such contextual features to existing models of policy implementation and regulatory compliance, we examine how regulatory factors are related to basic and proactive corporate environmental management practices in the Pearl River Delta region in China. Drawing on data derived from both a survey and in‐depth interviews, we show that a perception of clear political commitment to environmental protection across multiple government levels and units is positively associated with business efforts in basic environmental practices, regardless of the specific enforcement intensity. Nevertheless, a perception of clear political commitment is not related to proactive environmental practices. Conversely, a perception of policy ambiguity, in the form of confusing regulatory standards and enforcement, is negatively associated with corporate efforts in both basic and proactive environmental practices; yet, intensive inspections mitigate these negative associations with policy ambiguity.  相似文献   
12.
The aim of this work is to characterize the original concrete from Roman buildings for public spectacles, theatre and amphitheatre, from Emerita Augusta, Mérida, Spain. An advanced knowledge of the Roman concrete composition is required for a reliable restoration and preservation of these ancient monuments. The concrete was studied through mineralogical (optical polarized microscopy and X-ray diffraction) and petrophysical (bulk and real density, open porosity to water and Hg, mechanical strength and ultrasonic velocity) analyses. With this work, it is possible to fill the gap that exists in this field and the characterization of the materials used in the Roman concrete from these two buildings, never previously studied, despite the significance of this archaeological ensemble, declared a World Heritage Site by UNESCO in 1993. The results allowed us to determine the composition of the Roman concrete and to infer the provenance of the aggregates used in these monuments.  相似文献   
13.
Determining hand laterality during human evolution is important in order to identify brain hemispheric lateralization for motor tasks and, indirectly, to gain information on the complex cognitive functions of the human brain. In this paper, we present a new method for inferring handedness from lithic evidence. The study is based on an analysis of the scatter patterns of lithic remains from stone-knapping episodes. An experimental programme was carried out by 14 knappers (eight right-handed and six left-handed), ranging from individuals that had never even struck two pebbles together to individuals who were quite familiar with prehistoric tools and had some degree of practice. The results of the experiment show that the material scatter patterns of right- and left-handed knappers at group level are different, but they do overlap at certain intervals. At the individual level, the probability of falsely ascribing left- and right-handedness has also been estimated. In addition, we have adapted this method to be applied to the archaeological record. In this case, only well-preserved knapping events with no post-depositional alterations can be used to assign left- or right-handed knappers, with the former being more reliably detected than the latter.  相似文献   
14.
Strengthening social, economic and territorial cohesion is a central objective of the European Union (EU) and the Structural Funds reflect the main financial effort of the EU to pursue this goal. So far we have gone through four programming periods; to what extent the EU Funds have become more effective in promoting growth and reducing the disparities between EU Member countries is a matter of concern. We investigate the existence (or not) of learning effects and efficiency improvements following the reforms of Regional Policy. The study is applied to data from EU regions (EU12) in the most recent programming periods where data are available. The results suggest an improvement of the Funds efficiency in growth in 2000–2006 when compared to the previous programming period. Moreover, the returns from investments of Funds tend to be higher in richer, higher-educated and more innovative regions. Finally, the Cohesion group has not been able to transform the large transfers received into additional growth.  相似文献   
15.
Portus Ilicitanus (Picola, Alicante) was the main sea harbour of the Roman Colonia Iulia Ilici Augusta and as such played a crucial role in the supply of fundamental commodities to the Iberian Peninsula. Excavations yielded large quantities of glass in fourth‐ and early fifth‐century contexts. Elemental analysis of 60 samples by laser ablation – inductively coupled plasma – mass spectrometry (LA–ICP–MS) confirmed that the glasses were imported from the Eastern Mediterranean. A majority of the glasses correspond to the HIMTa primary production group, which originates from Egypt. The statistical evaluation of published data of 589 HIMT glasses further revealed differential distribution patterns of the HIMTa and HIMTb subtypes between the Eastern and Western Mediterranean, suggesting chronological trends that are linked to wider geopolitical changes. This demonstrates the need for systematic large‐scale approaches to identify supply patterns and possible factors underlying geographical differences and/or chronological developments.  相似文献   
16.
17.
We have investigated the survival of PCR-amplifiable mitochondrial and nuclear DNA in a small number of modern and medieval bovine leather samples. The results of this preliminary investigation demonstrate that, while no nuclear DNA can be PCR-amplified from any of the specimens, mitochondrial DNA can be amplified from all samples. To investigate this contrasting pattern of DNA survival further, we have vegetable-tanned cow skin in our own laboratory, and directly assayed the survival of PCR-amplifiable mitochondrial and nuclear DNA at each step of the process. The results indicate that nuclear DNA is reduced to sub-amplifiable levels as a result of the tanning baths, whereas amplifiable mitochondrial DNA survives the complete process. Our results suggest that old and archaeological bovine leather may represent a useful source of genetic information, although this information will most likely be limited to that which can be gained from mitochondrial DNA.  相似文献   
18.
This paper evaluates the impact of accessibility on the productivity of Spanish manufacturing firms. We suggest the use of accessibility indicators of workers and commodities, integrating transport, land use, and individual components, computing real distances or traveling times using the Spanish full road network. Estimated firms’ total factor productivity is explained as a function of the accessibility indicators and additional control variables. Results evidence the crucial role on firms’ productivity to the accessibility of commodities and to a slightly lesser extent the workers.  相似文献   
19.
This paper compares left-wing Latin American populism with Donald Trump. Despite their different social bases and economic policies, they use a similar logic to construct politics as an antagonistic struggle between two camps. Left-wing and right-wing populists aim to rupture existing political institutions to give power to the people, yet they differ in how they construct this category. Whereas Trump used ethnic criteria to differentiate the people from three out groups – Mexicans, Muslims, and African-American militant organisations – left-wing Latin American populists used political and socio-economic criteria. Despite their democratising promises, Latin American populists like Hugo Chávez in Venezuela and Rafael Correa in Ecuador undermined democracy from within. Even though stronger institutions might protect American democracy, Trump has disfigured democracy.  相似文献   
20.
López-Gappa, J., Pérez, L.M. & Griffin, M. February 2017. First record of a fossil selenariid bryozoan in South America. Alcheringa XX, xxx-xxx. ISSN 0311-5518.

Selenariidae Busk 1854 (Bryozoa) is considered endemic to Australia and New Zealand. Here we describe a new species of Selenaria Busk 1854 from the lower Miocene Monte León Formation (Patagonia, Argentina). Selenaria lyrulata sp. nov. is characterized by autozooids with a lyrula-like, anvil-shaped cryptocystal denticle, opesiular indentations and lateral condyles, as well as avicularia with a shield of fused costae. This is the first record of a selenariid bryozoan in South America.

Juan López-Gappa [] CONICET—Museo Argentino de Ciencias Naturales. Av. Ángel Gallardo 470, C1405DJR, Ciudad Autónoma de Buenos Aires, Argentina; Leandro Martín Pérez [] and Miguel Griffin [], CONICET—División Paleozoología Invertebrados, Museo de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina.  相似文献   

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