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1.
The term‘Ediacara Biota’(or many variants thereof)is commonly used to refer to certain megascopic fossils of Precambrian and early Palaeozoic age e but what does the term actually mean?What differentiates a non-Ediacaran‘Ediacaran’and an Ediacaran‘Ediacaran’from an Ediacaran non-‘Ediacaran’?Historically,the term has been used in either a geographic,stratigraphic,taphonomic,or biologic sense.More recent research and new discoveries,however,mean that the term cannot actually be defned on any of these bases,or any combination thereof.Indeed,the term is now used and understood in a manner which is internally inconsistent,and unintentionally implies that these fossils are somehow distinct from other fossil assemblages,which is simply not the case.Continued use of the term is a historical relic,which has led in part to incorrect assumptions that the‘Ediacara Biota’can be treated as a single coherent group,has obscured our understanding of the biological change over the PrecambrianeCambrian boundary,and has confused research on the early evolution of the Metazoa.In the future,the term‘Ediacaran’should be restricted to purely stratigraphic usage,regardless of affnity,geography,or taphonomy;suffcient terminology also exists where reference to specimens on a geographic,taphonomic,or biologic basis is required.It is therefore time to abandon the term‘Ediacara Biota’and to instead treat equally all of the fossils of the Ediacaran System.  相似文献   

2.
This paper critically synthesizes empirics and issues in discrete inter-disciplinary literatures to identify ‘open innovation’ as part of an emergent regime of accumulation, overlaying and co-existing with flexible production, and encompassing novel firm-level strategies, new forms of corporate networks, and a disturbing capital-labor relation that informalizes innovative work while cultivating entrepreneurial but self-exploiting subjects. I explain the novelty of open innovation, its genealogy, and the implications for people and conditions of work as much as for firms in a new topology of power relations. I cast the ensemble of strategies and tactics encompassed in open innovation as contingent, continually unfolding, and sometimes chaotic if not destructive for both firms and labor, in contrast to the celebratory tone in the business as well as geography and regional studies literatures regarding its benefits for competitiveness, innovativeness, value capture, and development. Open innovation – the externalization of innovation – entails long-run approaches to innovation and investment that are fraught with problems, prompting the development of short-term tactics to engage the challenges. One short-run strategy, crowdsourcing, bypasses the conventional web of inter-firm relations to connect digitally with individuals of the global crowd, enabling firms to reap the benefits of the crowd’s innovative talents, often without remuneration under circumstances that institutionalize informal work. These neoliberal subjects are best understood in terms of multiple subjectivities. I close by connecting the crowdsourcing of innovative with non-innovative work, both of which are parts of the emergent regime associated with new hiring and work practices that usher in new modes of exploitation.  相似文献   

3.
Urs Geiser 《Geoforum》2012,43(4):707-715
In recent years, the Swat valley in North-West Pakistan has witnessed various waves of ‘politics’. Different groups have attempted to change socio-economic conditions, each according to their clear visions of a better future. After a period of top-down attempts at modernisation by the state, development projects inspired by deliberative democracy have attempted to increase political space for ‘local people’, but failed. Swat has also witnessed agonistic politics, with the emergence of a fundamentalist social movement that constructed a radical discourse of otherisation, entering into an antagonism with the state that created war and havoc. Thus, Swat offers a challenging learning ground to reflect on practices for producing change, as well as on theoretical currents in academia. I argue that deliberative and radical theorising provide insights into the political life of Swat, but fall short analytically (missing social complexities), procedurally (favouring specific techniques of social negotiation), and normatively (due to preconceived understandings of a ‘better future’). I substantiate my argument by showing that both positions take euro-centric conceptualisation of ‘citizens’, a (modern) ‘state’, and ‘citizen/state relations’ as universals – basic conditions that are not met in the post-colonial setting of Swat. I therefore argue that our curiosity should be redirected from ontologised explanation to an analysis of actual practices of societal negotiation and the norms within which these are embedded. Such insights will make it possible for us to appreciate the enormous challenges people in Swat face in their struggle to negotiate aspirations among disparate voices and to imagine some common understanding of a ‘better future’ – challenges that go beyond what deliberative or agonistic theorising can offer.  相似文献   

4.
Social practice theories provide a unique platform for understanding how everyday practices become globalised through migration, spreading from one place to another, replacing local, often more sustainable, variations. Set in the context of the spreading of resource-intensive practices such as multiple daily showers, we explore the movement and migration of domestic practices, acknowledging that they are constantly shifting from one relatively stable form to another. Drawing on the phenomenon of human migration where, for various reasons, people move from one country to another, we argue that migrants ‘carry’ practices which can ‘travel’ between and across cultures, generations and living arrangements. People who migrate from one place to another are exposed to a greater range of practices than other more sedentary populations. On encountering new practices in the destination country, we propose the practices carried by migrants are subject to various forms of integration, disintegration and transferral across generations. Borrowing the idea of muscle memory from the biophysical sciences, we introduce ‘practice memory’ to explain how some practices thought to be ‘dead’ can be resurrected with relative ease. We also suggest that practice memory may explain how some practices can be performed in new contexts despite a person never having performed them before. We conclude by reflecting on how understanding these migratory processes, and the role of practice memory within them, offer new insights into how practices move and migrate from one time–space to another.  相似文献   

5.
The ‘just transition’ is a concept receiving more attention in the literature to-date. This critical review discusses this and how there are overlaps with literature on energy, environmental and climate justice. Within the separate energy, environment and climate change scholar communities, there is too much distortion of what the ‘transition’ means and what ‘justice’ means, and they all should be understood within the just transition concept. To increase public understanding and public acceptance of a just transition, these research communities need to unite rather than continue alone.  相似文献   

6.
L.L. Sloss 《地学学报》1992,4(3):320-328
Over the past one hundred years North American geologists have been influenced by concepts of Earth history based on periodic events involving marked (‘Neocatastrophic’) changes and competing concepts involving steady-state (‘Uniformitanan’) behaviour. T.C. Chamberlin, a late 19th-/early 20th-Century exponent of a nonuniformitarian scenario of earth history, proclaimed ‘diastrophism as the ultimate basis of correlation’ - meaning that geological history is punctuated by orogenic paroxysms causing retreat of epicontinental waters to oceanic basins, creating segmentation of the stratigraphic and chronological record. At mid-Century James Gilluly gained wide support for the proposition that orogeny has followed a Uniformitarian, near-steady-state course. Accordingly, episodic diastrophism is a myth and cannot be the basis for periodic eustatic sea-level change, interregional unconformities, etc. In more recent decades two powerful new influences on geological thought have emerged. The global tectonic paradigm has forced upon us the realization that rearrangements of lithospheric plates are capable of changing the freeboard of continents. At the same time technological advances in the acquisition and processing of seismic-reflection data have been seized by receptive minds to organize the newly available stratigraphic imagery for application to the discipline of seismic stratigraphy which emphasizes the identification and correlation of unconformity-bounded successions of strata. Expansion of the methodology to the outcrop, beyond the limitations of seismic resolution, has brought about the flowering of the New Sequence Stratigraphy, doctrine that has deservedlyachieved wide application and acclaim. Practitioners of sequence stratigraphy, impressed by the distances over which unconformity-bounded stratal units can be correlated, hew to the belief that eustatic (commonly glacially engendered) sea-level change is the control. This paper examines evidence of tectonic episodes affecting cratons and their margins. These offer promise of a more satisfactory understanding of stratigraphic sequences and of the Earth history they represent. Consideration of these matters makes it inescapable that the elevation and subsidence of cratons (and their component basins and arches) reflect tectonic phenomena of the continental lithosphere quite independent of eustatic events.  相似文献   

7.
South Australia’s State Heritage Register contains 2294 listed places, the majority of which are from the ‘Built’ environment, ranging from settlers’ huts, community buildings, historical industrial sites to magnificent stone mansions. Only 96 places are linked to the ‘Natural’ environment. The Register listings protect heritage places from alteration, damage or removal without formal prior consultation, compulsory under the South Australian Development Act. ‘Natural’ environments are landscape-based and oriented towards Geological, Archaeological, Palaeontological and Speleological heritage (‘GAPS heritage’). A process to provide a greater balance between ‘Natural’ and ‘Built’ listings has initiated a series of State Heritage ‘Natural’ environment assessments, mostly of single sites. Two individual caves in the Naracoorte Caves National Park are already entered in the State Heritage Register as single sites. However, an innovative broader multiple-site nomination has focused on the many different but significant GAPS features contained within the 25 caves of the Naracoorte Caves National Park, providing a further level of protection for the land and the caves’ exteriors and interiors. The example of the Naracoorte Caves draws attention to the number of important land and coastal karst (limestone) features across South Australia that were generated by steady geological uplift of three large sections of Oligocene–Miocene limestone—the Nullarbor Plain, the Murray Basin and the Gambier Karstfield (which includes Naracoorte and Mount Gambier), resulting in specific karst forms worthy of a broader coordinating management approach across South Australian karst parks.  相似文献   

8.
水流在非饱和土体中的入渗过程实质上是水在下渗的过程中驱替空气的两相流问题。为揭示非饱和花岗岩残积土水-气两相驱替动态渗流机理,选取福州某地原状花岗岩残积土作为研究对象,基于工业CT扫描图像与Level Set方法,研究了原状土样两相驱替的动态特征。结果表明:对于细观尺度水-气两相驱替模拟,Level Set法能很好地捕捉两种不混溶流体间的界面位置;水-气两相驱替过程存在大孔隙优先流特征,且“绕流”现象一般易于出现在孔隙成圆度较高处;两相渗流速度主要受孔道迂回度控制,笔直、较宽孔道,渗流速度相对较高,同时存在明显的“优势通道”,且随渗流时间增大以先急后缓的特征呈正相关变化,最大增速率为 10.77%,最小仅 1.90%;孔道横截面速度大小分布与孔隙结构有关,“回流”和“绕流”现象会使驱替速度骤降,降低幅度可达21.62%;驱替阻力最大出现在孔壁处,孔道越窄,阻力越大;驱替效率与驱替压差成正比关系,且初期加压增速效果显著,可达25.49%,后期仅为1.47%。该研究成果可丰富降雨型滑坡理论基础并预防灾害产生,具有重要的理论价值及工程意义。  相似文献   

9.
This paper examines, first, the conditions under which irrigating farmers are being alienated from their water through a state-led process of dispossession, and then, second, details the dialectical process of farmers’ resistance to these efforts. The paper advances recent scholarship on water grabbing and ‘accumulation by dispossession’ by drawing on a case from northwestern India to explore the connections between non-agrarian economic growth, irrigated agriculture and farmer livelihoods. Specifically, it examines an urban water infrastructure development project that aims to provide water to Jaipur, the Indian state of Rajasthan’s capital city, through the appropriation of an existing rural dam/reservoir complex built for irrigation and redirecting it to domestic, commercial and industrial uses. Drawing on an examination of policy documents and interviews with farmers and state planners, this paper argues that these transfers must be understood as a supply-side solution to support economic growth, where the lack of stable water supplies is a barrier to capital accumulation. The paper contributes to critical scholarship by showing that the processes underpinning water’s reallocation are specific acts of ongoing ‘dispossession’ through extra-economic means under advanced neoliberal capitalism, which alienates water away from peasant producers towards new centers of capital accumulation, dialectically creating peasant resistance to these efforts.  相似文献   

10.
The terminology of structures in thrust belts   总被引:1,自引:0,他引:1  
A review of structures and geometric relationships recognized in thrust belts is presented. A thrust is defined as any contractional fault, a corollary being that thrusts must cut up-section in their transport direction. ‘Flats’ are those portions of a thrust surface which were parallel to an arbitrary datum surface at the time of displacement and ‘ramps’ are those portions of thrusts which cut across datum surfaces. Ramps are classified on the basis of their orientation relative to the thrust transport direction and whether they are cut offs in the hangingwall or footwall of the thrust. Lateral variations in the form of staircase trajectories are joined by oblique or lateral ramps which have a component of strike-slip movement.An array of thrusts which diverge in their transport direction may form by either of two propagation models. These are termed ‘piggy-back’ propagation, which is foreland-directed, and ‘overstep’ propagation which is opposed to the thrust transport direction. An array of thrust surfaces is termed an ‘imbricate stack’ and should these surfaces anastamose upwards a ‘duplex’ will result; the fault-bounded blocks are termed ‘horses’. A duplex is bounded by a higher, ‘roof’ thrust and a lower, ‘floor’ thrust. The intersection of any two thrust planes is termed a ‘branch line’.Thrusts can be classified on the basis of their relationship to asymmetric fold limbs which they cut. A further classification arises from whether a particular thrust lies in the hangingwall or footwall of another one.The movement of thrust sheets over corrugated surfaces, or the local development of thrust structures beneath, will fold higher thrust sheets. These folds are termed ‘culminations’ and their limbs are termed ‘culmination walls’. Accommodation of this folding may require movement on surfaces within the hangingwall of the active thrust. These accommodation surfaces are termed ‘hangingwall detachments’ and they need not root down into the active thrust. This category of detachment includes dip-slip ‘hangingwall drop faults’ which are developed by differential uplift of duplex roofs, and ‘out-of-the-syncline’ thrusts which develop from overtightened fold hinges. Back thrusts, as well as forming as hangingwall detachments, may also form due to layer-parallel shortening above a sticking thrust or by rotation of the hangingwall above a ramp.  相似文献   

11.
Although contemporary policy making is substantially affected by consultants, little is known about the interconnection of their role inside policy making networks and their key product – knowledge. This paper matches the approaches on Policy Mobilities (PM) and Territorial Knowledge Dynamics (TKD) to fill this theoretical gap. By exploring the synergies of both concepts, a research agenda is suggested that enables to investigate the multi-facetted entanglements of knowledge and policy making dynamics as well as what stake consultants have in this complex assemblage. Accordingly, this paper claims appreciation of ‘variegated consultocracies’ rather than global homogeneity of consultants’ engagement in policy making processes by explicating better integration of ‘scale, ‘time’, and actors’ embeddedness into PM. The paper thus primarily aims to provide a solid theoretical and methodological basis for exploring the complex dynamics consultants take part in, and how they in turn impact policy making processes.  相似文献   

12.
Sharma  Madhuri  Abhay  Rajesh Kumar 《GeoJournal》2022,87(4):797-819

One out of three people in India is urban. In 2011, there were about 53 urban agglomerations larger than 1 million population as against only 35 in 2001. Much of this urban expansion has been occurring in the country’s largest metropolises including the National Capital Territory of Delhi which has expanded horizontally and vertically both. This has also added to overall decline in its already dilapidated housing stock and quality of life. Delhi, a historical hub for regional, national, and international commerce, and a place for the socio-political elites, has failed to provide basic life amenities to its average citizens. This research critiques the (un)sustainable elements of Delhi’s urbanization and concomitant decline in basic amenities pertaining to quality-of-life by examining the growth and expansion of its urban-built-up areas during 2001–2011–2020 and provides nuanced insights into its ‘livability’ by examining select quality-of-life attributes. The LANDSAT imageries for 2010 and 2020 are used to measure NDB-Index that assesses its built-up area and change, which are later corroborated with Census household data to examine change in its ‘livable’ and ‘dilapidated’ housing structures. Significant sub-regional disparity exists in the availability of good and livable homes, with almost 20–30% of several districts still without drinking water source inside premises. However, significant progress is also noted for basic amenities like lighting, latrine and bathing facilities, and majority of Delhi’s built-up area has expanded along newer developments and transportation corridors. This calls for goal-oriented strategic interventions by policymakers to help achieve the SDG-11 on Sustainable Cities.

  相似文献   

13.
Several international initiatives, including the World Economic Forum (WEF), aim to constitute biodiversity loss as a material risk to the ‘bottom line’ calculations of investors and insurers. The WEF claims that while no sector ‘escapes untouched by some form of biodiversity risk’, such risks can be transformed into opportunities, and ideally, profit. I trace the key actors, reports, and methodologies producing ‘biodiversity loss as risk’, and outline some of the challenges, paradoxes and implications of this transformation. In particular, I show how biodiversity loss is a difficult to transform into an individuated risk that can cause firms to act otherwise. However, new calculative devices are emerging to help individuate and calculate biodiversity risks for firms. In this paper I focus on two of such devices, the Integrated Biodiversity Assessment Tool (IBAT) and the Corporate Ecosystem Service Review (CESR). Both tools aim to render biodiversity loss legible in the language and metrics of financial risk. These tools devised to produce biodiversity risk, I argue, have effects. They are changing the way that conservation knowledge is produced, producing new spaces for investment and disinvestment, and are also re-defining the very subject of conservation.  相似文献   

14.
Due to the importance of venture capital (VC) firms in spurring regional economic growth, the geography of VC firms and VC investments have attracted a lot of attention. However, the spatial patterns of cross-regional VC flows have rarely been explored, particularly in the context of emerging economies. Drawing on a unique dataset on VC firms and investments related to domestic initial public offerings (IPOs), this study combines location analysis with network analysis to investigate the spatial patterns of VC activities in China. The results confirm that Beijing, Shenzhen and Shanghai are the leading VC centres in the country. Although Yangtze Delta Area hosts the largest number of investments, Beijing and Shenzhen have a considerable advantage over Shanghai in terms of the number of VC firms, investments, and the number of domestic VC-backed IPOs. Beijing and Shenzhen also appear more central than Shanghai in China’s VC networks, with Beijing-Shenzhen representing the most important city-dyad in terms of VC investment flows. The article explains how the dynamics of the VC centres is embedded in China’s institutional and cultural context, critical to understanding the evolution and geography of China’s VC industry.  相似文献   

15.
Salt weathering is a crucial process that brings about a change in stone, from the scale of landscapes to stone outcrops and natural building stone façades. It is acknowledged that salt weathering is controlled by fluctuations in temperature and moisture, where repeated oscillations in these parameters can cause re-crystallisation, hydration/de-hydration of salts, bringing about stone surface loss in the form of, for example, granular disaggregation, scaling, and multiple flaking. However, this ‘traditional’ view of how salt weathering proceeds may need to be re-evaluated in the light of current and future climatic trends. Indeed, there is considerable scope for the investigation of consequences of climate change on geomorphological processes in general. Building on contemporary research on the ‘deep wetting’ of natural building stones, it is proposed that (as stone may be wetter for longer), ion diffusion may become a more prominent mechanism for the mixing of molecular constituents, and a shift in focus from physical damage to chemical change is suggested. Data from ion diffusion cell experiments are presented for three different sandstone types, demonstrating that salts may diffuse through porous stone relatively rapidly (in comparison to, for example, dense concrete). Pore water from stones undergoing diffusion experiments was extracted and analysed. Factors controlling ion diffusion relating to ‘time of wetness’ within stones are discussed, (continued saturation, connectivity of pores, mineralogy, behaviour of salts, sedimentary structure), and potential changes in system dynamics as a result of climate change are addressed. System inputs may change in terms of increased moisture input, translating into a greater depth of wetting front. Salts are likely to be ‘stored’ differently in stones, with salt being in solution for longer periods (during prolonged winter wetness). This has myriad implications in terms of the movement of ions by diffusion and the potential for chemical change in the stone (especially in more mobile constituents), leading to a weakening of the stone matrix/grain boundary cementing. The ‘output’ may be mobilisation and precipitation of elements leading to, for example, uneven cementing in the stone. This reduced strength of the stone, or compromised ability of the stone to absorb stress, is likely to make crystallisation a more efficacious mechanism of decay when it does occur. Thus, a delay in the onset of crystallisation while stonework is wet does not preclude exaggerated or accelerated material loss when it finally happens.  相似文献   

16.
Reversals in vertical crustal motion, alternations between uplift and subsidence over time scales of hundreds of thousands of years or more, have been identified in Late Cenozoic fluvial sequences in many regions worldwide. They form a class of fluvial archive that is distinct from the extreme stability observed in Archaean cratons and the monotonic uplift or subsidence that is widely observed in other regions. Such alternations between uplift and subsidence are characteristic of regions of Early or Middle Proterozoic crust, where the initial crustal consolidation included the development of a thick ‘root’ of mafic material at the base of the crust; the present study focuses on localities with this crustal type in the USA and eastern Europe. It has previously been suggested on the basis of uplift modelling that this style of crustal behaviour occurs only in regions where the mobile lower‐crustal layer is relatively thin. This study supports this conclusion on the basis of independent geothermal calculations, which indicate that such alternations between uplift and subsidence occur where the mobile lower‐crustal layer is ≤~7 km thick. An understanding of this phenomenon, in relation to the understanding of vertical crustal motions induced by surface processes (and thus by climate change) in general, therefore requires analysis of the properties and dynamics of the mobile lower‐crustal layer; detailed analysis of fluvial sequences thus contributes unique information in this area.  相似文献   

17.
Our understanding of monsoon circulation timing’s at the orbital scale is currently a matter of debate. Here, we compare previous and recently published results of Indian, East Asian, West African and East African monsoon variability. We note different timings between the East African, West African, Indian and East-Asian monsoon systems for the most recent 45 ka, where the age models are constrained by AMS dating. On this basis, we construct different orbital forcing “reference curves” and apply them to the 200 ka time period for the different monsoon systems. Our results indicate that the ‘global monsoon’ concept at the orbital scale is a misnomer. We find real regional differences in the timing of the monsoon response to orbital forcing and differences in the weight of precession and obliquity in the monsoon records. This work highlights the necessity of studies aimed at understanding the underlying physics of these regional response patterns. This is crucial to a better understanding of monsoon dynamics and improved climate model simulations and comparisons with proxy data.  相似文献   

18.
This paper examines the increasing complexity of interactions between temporary staffing agencies and their client firms within the local labour market of Birmingham, UK. Temporary Staffing Agencies have been identified as active and influential agents in local, national and international labour markets. Their influence on local labour market functioning, national labour regulation and international regulatory frameworks is growing. Existing literature demonstrates the power of large multinational temporary staffing agencies in both established and emerging temporary staffing markets. Such analyses also contend that multinational agencies operate in very different ways to smaller independent ‘back-street’ temporary staffing agencies, with different types of clients and at different ends of the market. However, the research conducted in Birmingham, UK suggests that the reality is more complex. It is argued that there can be more subtle and intricate nuances of relevance to the temporary staffing industry in respect of the relationships that exist between large and small temporary staffing agencies, as well as between such agencies and their clients. We highlight how smaller agencies in Birmingham are utilising a variety of strategies and tactics to creatively ‘bolt-on’ to more formalised national agreements established by multinational agencies with their clients. Moreover, smaller agencies – in some instances – are able to exploit their knowledge of local labour markets to subvert, sabotage and/or infiltrate the activities of multinational agencies in increasingly astute ways. In turn, this generates a series of questions for understanding the nature of ‘market making’ associated with the temporary staffing industry more broadly.  相似文献   

19.
Jörg Maletz 《Geology Today》2017,33(6):233-240
Every student of palaeontology will stumble upon the term ‘graptolite’ at some point and will wonder what these strange little fossils mean. Thought to be long extinct, the few living graptolites and their extinct relatives have been united quite recently by palaeontologists through cladistic analysis. Not that the extant graptolites were overlooked, but the connection has never been made between the fossil graptolites and their modern descendants. We now have a much better scientific basis for our interpretation and understanding of these fossils and graptolites are recognized as part of a living clade of small and inconspicuous marine organisms, the Pterobranchia. They have been around since the Cambrian Period (c. 520–510 Ma) and, thus, they may represent one of the longest‐existing groups of organisms. Not that they should be termed ‘living fossils’, but their perseverance is remarkable in its own way and may lead to the question as to how they were able to achieve this success and survive for all these eons. May they be able to show us a key to survival in the future?  相似文献   

20.
Research into the music industry has for a long time been almost exclusively dominated by a focus on the production of albums and songs. In recent years, however, cities such as Stockholm have seen the growth of a profitable and varied music services industry producing everything from remixes to music marketing strategies. Standing at the forefront of this growth industry are a large number of firms attempting to combine in innovative ways music and ICT. This can take a variety of forms, for instance: selling and distributing music over the internet; web design and computerised advertising services tailored to music products; software design focused on multimedia products and virtual instruments; high-tech post-production and mixing services; and virtual centres and communities of music industry actors. The article will examine these activities within the city in attempt to measure the direction and cohesiveness of the emerging sector. The article concludes by arguing that these type of new industrial synergies tell us much about the way industrial innovations are formed in an interindustry and inter-cluster environment, and the future competitiveness and shape of the music industry. In particular, the article argues that evidence from Stockholm points to the emergence of a post-industrial musical economy.  相似文献   

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