Fertile Zones Research Articles

Using AMS and Palaeomagnetic Data to Assess Tectonic Rotation: A Case Study from Savannah Nickel Mine, WA

Recent research has shown that Ni-PGE mineralisation is typically associated with specific intrusion types, e.g., chonoliths, bladed-dykes and funnels that acted as high-throughput magma conduits within much larger magmatic provinces. The initial architecture of these systems is very different, but additional structural modification during orogenesis can render such intrusions very difficult to understand structurally, and hence make it very difficult to target the fertile zones within the system. In structural geology it is common to evoke shortening directions, which are assumed to apply to all rocks regardless of their rheology. This is not realistic. Furthermore, resolving the partitioning of strain is not straightforward for intrusive rocks, which tend not to develop visible tectonic fabrics, but act as rigid blocks that rotate to accommodate strain, rather than compress or shear, during deformation. Unfortunately there are few structural techniques that can be used to quantify such rotation. Intrusions near the Savannah Nickel Mine, East Kimberley, WA were observed to have different deformation histories, despite being temporally equivalent. In this study we measured anisotropy of magnetic susceptibility (AMS) and remanent magnetisation in two adjacent, temporally equivalent, intrusions. The observed K3 AMS vectors are typically normal to the magmatic layering in layered intrusions. Where K3 vectors sit along a great circle, the pole to that great circle indicates the rotation axis. Original palaeomagnetic vectors would be expected to be consistently oriented with respect to magmatic layering, and can be used similarly to test the consistency of the inferred rotation analysis. The rotations inferred for the intrusions tested were consistent between the two techniques. Savannah and Savannah North, were subjected to N-S, NE-SW and NW-SE shortening, consistent with the Halls Creek Orogeny. However, N-S shortening was dominant at Savannah and NE-SW dominant at Savannah North. Therefore, despite their equivalent emplacement ages and implied tectonic history, each intrusion has undergone very different deformation.

Leaf and inflorescence evidence for near-basal Araceae and an unexpected diversity of other monocots from the late Early Cretaceous of Spain

Phylogenetic analyses imply that monocots were a key group in the early radiation of angiosperms, yet they are much rarer than other major clades in the Early Cretaceous macrofossil record. Here we describe a well-preserved leaf and several inflorescences related to the near-basal monocot family Araceae and abundant monocot leaves of uncertain affinities from two latest Albian localities in north-eastern Spain. Orontiophyllum ferreri sp. nov. has a multistranded midrib, several orders of parallel-pinnate veins, two orders of transverse veins, and paracytic-oblique stomata. This suite of characters (but with both anomocytic and paracytic-oblique stomata) is characteristic today of Orontium in the near-basal araceous subfamily Orontioideae, and later Cretaceous and early Cenozoic leaves assigned to Orontiophyllum have similar architecture. Sedimentology and anatomy suggest a (semi)aquatic ecology. Other monocot leaves at the same locality are linear and parallel-veined but have similar stomata. Although anomocytic stomata have been proposed as ancestral in monocots, O. ferreri, the associated linear leaves, Albian–Cenomanian cuticles from Australia and Portugal, and extant data are consistent with the hypothesis that variable paracytic-oblique stomata are ancestral. Turolospadix bogneri gen. et sp. nov., from the other locality, includes spadices of ebracteate flowers with four tepals, a central gynoecium, and a long stipe (vs a spathe attached just below the fertile zone as in most Araceae). Phylogenetic analyses indicate that the character combinations seen in O. ferreri and T. bogneri are ancestral for Araceae, and they could be either sister to Araceae or nested within a basal grade of the family. Together with fossils from the Aptian–Albian of Brazil and Portugal, the Spanish fossils indicate that Araceae are among the oldest extant monocot families, but they were associated with diverse linear-leaved monocots of uncertain affinities.

Neutronic study of an ASTRID-like fast reactor core with thorium-based fuel

Abstract In this work the utilization of thorium was investigated in a sodium-cooled ASTRID-like fast reactor core. Two thorium fueled strategies were analyzed and compared with the reference core in which the fuel vector is composed of a mixture of U-Pu MOX fuel. For the first strategy, all uranium isotopes in the fertile zone (depleted uranium) were replaced by a mixture of 232Th/233U, leaving the fissile zone with the U-Pu MOX composition. For the second strategy, the whole core, that is, the fertile and fissile zones were loaded with a mixture of 232Th/233U. The Monte Carlo MCNP6 code with the ENDF/B-VII.0 cross section library was used to perform the calculations. Six neutronic parameters were analyzed for each fuel strategy: the neutron energy spectrum, the effective neutron multiplication factor (keff) for an operating cycle of 365 days, the Doppler constant, the reactivity effect of the coolant density, the effective delayed neutrons fraction (βeff) and the shutdown margin. The main isotopes evolution and the radial power distribution were also analyzed. Results show that the energy spectrum is harder with high thorium fraction, i.e. in the case with 232Th/233U in the whole core. The behavior of keff along the operating cycle of the reference core and that of the case with 232Th/233U in the fertile zone is very similar, getting the second one a slightly higher keff at the end of cycle. The keff with 232Th/233U in the whole core has a significant loss in reactivity and need further research. As for the isotopes, in the reference core 239Pu is bred, the same happens with 233U in the core with 232Th/233U in the fertile zone. This does not happen with 232Th/233U in the whole core. The Am and Cm actinides concentrations are lower with 232Th/233U in the fertile zone than in the reference core and are completely absent with 232Th/233U in the whole core. For all the configurations the Doppler constant and the reactivity effect of coolant density behave well, as the keff drops with temperature raise or with void raise. In the case of sodium voiding, a better performance is observed with 232Th/233U in the whole core. The power distribution is alike in all core configurations, having a ring with the higher power in the outer fuel region. The full 232Th/233U fuel configuration have the more even power distribution. All core configurations have similar βeff and show a satisfactory shutdown margin, as it is higher than 1% dk/k at the beginning of cycle.

Functional diversity and convergence in the evolution of plant reproductive structures

Structures that simultaneously perform many functional roles are likely to show a variety of morphological solutions to these demands, and thus probably exhibit high morphological disparity. In contrast, specialization for a few simple functions should result in a more limited suite of morphologies. We explore this idea using lycopsid reproductive structures, which, throughout their history, have performed a limited set of functional roles compared with the reproductive structures of other plant groups such as seed plants. We scored living and fossil lycopsid taxa for 18 discrete character measurements and several continuous traits, including sporangium size, supporting axis diameter, and strobilus length and width. We used the discrete characters to construct a multivariate morphospace for lycopsid reproductive morphology through time, and the continuous characters to test whether fossil and extant lycopsids show similar patterns of tissue allocation within reproductive structures. Lycopsids occupy similar areas of reproductive morphospace and show similar patterns of tissue allocation over most of their history, alternating between diffuse fertile zones with leaf-like sporophylls and compact strobili with specialized sporophylls that allow sporangia to be closely packed while also protected during their development. Growth habit also plays an important role in lycopsid reproductive evolution, broadly influencing the size and shape of reproductive structures. Lycopsid reproductive structures are primarily specialized for densely packaging sporangia, and are consistent with the idea that performing limited functional roles is associated with reduced morphological disparity. Morphologies similar to lycopsid strobili are also found in other groups with simple, wind-dispersed propagules, suggesting that the same processes occur across plant lineages.

Uncertainty assessment on the calculated decay heat of the ASTRID basic design core based on the DARWIN-2.3 package

A good knowledge of the decay heat of the various elements of the core (fissile and fertile zones, structures, sodium…) as well as the associated uncertainties is critical for the safe operation of a nuclear facility, but also at the design stage as in the case of the ASTRID technological demonstrator. For this reactor, the amount of decay heat is all the more important as it will strongly impact the design of the dedicated EPur (Evacuation de la PUissance Résiduelle = disposal of the decay heat) system.The uncertainties on the decay heat calculations of a sodium fast rector that are currently used at CEA were defined several decades ago and are now considered very conservative, because of the method that was used in their evaluation. They may thus be penalizing for the design and operation of ASTRID. These past uncertainty assessments were based on a semi-empirical approach - a combination of physical considerations and experimental results - and on calculations using conservative methods and obsolete nuclear data libraries that need to be updated.We have used up-to-date calculation tools in order to reduce these uncertainties: ERANOS-2.2 for the neutronic calculations and DARWIN-2.3 for the depletion calculations. The uncertainty on the decay heat is estimated with the CYRUS tool, which performs the propagation of all the relevant nuclear data uncertainties (decay constants, branching ratios, cross sections, independent fission yields). For some parameters, we have completed the JEFF-3.1.1 uncertainties database with values from other nuclear data libraries, for instance the branching ratio for the decay of 137gCs to 137mBa, of 90gKr to 90gRb and the branching ratio for the capture of 241gAm to 242gAm.The resulting 1σ uncertainty on the decay heat calculation never exceeds 2.6%, which shows a major improvement compared to the previous uncertainty evaluation that could reach 6.6%. Additional sources of uncertainties will have to be considered in the future in order to evaluate the full uncertainty on decay heat calculations: the reactor operation conditions variations, the accuracy of the nominal power measurement and the uncertainty on the neutron flux calculated with the new APOLLO3® code system, which will be dedicated to the ASTRID neutronic calculations.

Spatial analysis of soil resources in the Mewat district in the semiarid regions of Haryana, India

The soil characteristics are critical for crop health and its yield and therefore for agriculture. The soil properties are spatially variable and therefore soil resources should be managed as per location-specific requirements. An integrated spatial analysis of the soil resources of Mewat district was conducted to identify the soil resource management zones to develop site-specific soil management plan which might lead to sustained and enhanced crop yield. Spatial analysis of soil resources was conducted by modeling soil fertility and erosion which determines the crop productivity in the region. Soil fertility of the region was modeled using weighted overlay approach using 10 soil parameters, namely nitrogen, phosphorus, potassium, sulfur, iron, zinc, manganese, organic carbon, electrical conductivity, and pH. Each parameter was assigned weights based on their relative importance to agricultural productivity. The modeled soil fertility was classified into three fertility zones, low, medium, and high. Soil fertility was found to be low to moderate in 65% of the area, largely because of the low nitrogen, soil organic carbon, phosphorus concentration, and excessive salinity. Soil erosion was modeled using the universal soil loss equation (USLE) model by estimating rainfall erosivity factor (R), the soil erodibility factor (K), the topographic factors (L and S), cropping factor (C), and the conservation practice factor (P). Soil erosion problems were limited to areas having high elevation with barren land and areas with minimal management practices. The severity of soil erosion was found high in 15% of the region, while the remaining 85% showed low to moderate erosion. Soil fertility and erosion were integrated using the multivariate clustering method to identify soil management zones. The region was delineated into three soil management zones. Zone I (29%) which covers majorly Tarou block, was characterized by high soil fertility and low soil erosion. Zone II (18%) with medium soil fertility and high erosion covers villages of Taoru, Nuh, Nagina, FP Jhirka, and Punhana, which are located in the foothills of Aravalli ranges. Zone III represents the major part of the region, covering Nuh, Nagina, and FP Jhirka blocks (54%) with low soil fertility and erosion conditions. Thus, within the study area, the soil management domains are spatially variable in terms of fertility and soil erosion, and thus zone-specific soil management measures are required to improve the soil condition in order to sustain and improve agriculture production. The study would help the policy makers to design site-specific planning for identified soil resource management zones.

The use of representativity theory in the depletion calculations of SFR blankets

The analysis of the DOUBLON experiment has provided C/E’s for several isotopic ratios in the first and second rows of the radial blanket after an irradiation in the PHENIX Sodium Fast Reactor. We have used this as a basis for the validation of the DARWIN-2.3 (Tsilanizara et al., 2000) package for the depletion calculation in the radial blankets of SFR’s (Lebrat et al., 2015). Unfortunately, no measurements have been performed in the upper and lower axial blankets of the fissile assemblies. Of course we expect our calculations to be reliable in these zones as well, as the initial compositions, nuclear reactions and neutron spectra are very similar. The representativity theory appeared to be the appropriate tool to correlate the available experimental information in the radial blanket to our calculations in the axial zones. Indeed, the representativity factors that we calculate between the final 239Pu/238U ratio in the radial and axial fertile zones are very close to 1. Hence, the measurements performed in the radial zone can help us “correct” the calculation in the axial blanket and reduce its a-priori uncertainty due to nuclear data. The estimated uncertainty reduction can reach a factor 5, since the experimental uncertainty is low. The 240Pu/238U ratio is studied with a similar method.

Fissurina subcorallina(Lichenized Ascomycota: Ostropales), Another Drop in the Bucket

Komposch, H. 2016. Fissurina subcorallina (lichenized Ascomycota, Ostropales), another drop in the bucket. — Herzogia 29: 473–478.The fertile and isidiate lichen species Fissurina subcorallina is described as new from Costa Rica, where it was collected on a tree bole in the basal height zone of a moist lowland rainforest near the coastline. It is distinguished from the other isidiate Fissurina species by transverse (6–)7-septate ascospores and coralloid isidia. The crack-like lirellae are comparable with those of F. dumastii and are grouped in fertile zones.

Ammonia/Ammonium Toxicity Root Symptoms Induced by Inorganic and Organic Fertilizers and Placement

Ammoniacal fertilizers can cause seedling damage. The present aims were to characterize spatial and temporal, root morphological NH3/NH4+ toxicity symptoms, assess the extent of the toxicity zone, and relate species‐specific responses to their root architecture. Wheat (Triticum aestivum L.) and canola (Brassica napus L.) were exposed to seed and deep placed urea. Faba (Vicia faba L) seedlings were grown above organic amendments. Time‐sequential images of canola root apex and root hair die‐back, discoloration, and accelerated lateral rooting were captured with soil‐buried, high resolution digital scanners. Seed‐placed urea stunted wheat shoot and root radicles, while slow‐release urea reduced these symptoms. Primary axes of all three species were damaged by encountering the deep fertilizer zones. The multiple seminal axes and lateral root growth away from the fertilizer allowed greater wheat seedling survival, while toxicity‐damage to a single tap root of the germinating canola and faba often resulted in seedling mortality. Urea and chicken manure developed expanded NH3/NH4+ toxicity zones 1.5 to 5 cm, eliciting similar toxicity symptoms initiated at the root apex. Within 3 d after planting, canola tap root elongation stopped, followed by progressive basal directed necrosis and shrinking of the root axis, root hairs. These characteristic symptoms may be used for future toxicity diagnostics of soil‐grown plants. Elevated pH in the soil zone above the chicken manure suggested NH3 gas transported through soil pores followed by H+ consumption and elevated NH4+. Ammonia gas toxicity and species‐specific root system architecture should be considered in N placement and source selection.Core Ideas NH3/NH4+ toxicity initiates at the root apex and moves basipetally. Symptoms include tissue discoloration, axis shrinkage, root hair disfigurement, and seedling death. Toxicity zones ranged from 1 to 5 cm from the ammonia sources. Putative upward movement of ammonia raised soil pH and NH4+ above chicken manure. Most wheat axes avoided NH3/NH4+ toxicity zones, improving survival over tap‐rooted species.

A comparison between oxide and metallic fueled ASTRID-like reactors

In order to limit the greenhouse emissions and ensure energy security, the global climate change perspective implies a modification in the future energy sector supply. Nuclear energy is an alternative that would decrease the amount of greenhouse gas emissions, and specifically, the fourth generation reactors that present a favorable outlook for clean energy supply. In particular, the Advanced Sodium Technological Reactor for Industrial Demonstration (ASTRID) is a fourth generation sodium-cooled pool type fast nuclear reactor of 1500MWth that seems to be a promising design into the commercial fast nuclear reactors. One of the different core designs for ASTRID is a low void effect core (CFV: Cœur à Faible effet de Vidange sodium) due to the reactor configuration and the radial and axial position of the fuel subassemblies. The current paper presents a heterogeneous ASTRID model developed in MCNP6 with JEFF-3.2 cross sections library, in which three neutronic parameters (Keff at End of Cycle, Doppler constants and coolant void worth) are validated with the European Benchmark on the ASTRID-like low-void-effect core characterization, presented in the ICAPP conference in Nice, France, on May 2015. Validation of the ASTRID model was successfully accomplished, having slightly differences with the benchmark participants in the neutronic parameters. Once the validation was done, a metallic fueled ASTRID-like design is proposed and compared with the oxide fueled reactor. Criticality analysis was done in order to understand the reactor behavior during one cycle of operation as well as Doppler constants and coolant void worth comparison. Actinide inventory was analyzed for both models and 239Pu was tracked with the purpose of observing the breeding achieved in the fertile blankets. Reactivity at the End of Cycle had only a 3pcm delta Keff difference in comparison with the oxide design, Doppler constants behaved as expected and coolant void worth for the whole core has a negative reactivity effect, which is the essential characteristic of the CFV core. Metallic model performed 8.57% more breeding in isotope 239Pu than the conventional oxide fueled design in the fertile zone, and in the global actinide inventory achieved 3% more 239Pu. Metallic design enhances the plutonium management because, besides that the reactor can be sustained in a supercritical state with less initial Pu enrichment, breeding has a better performance.

Influence of Local Spectral Variations on Control-Rod Homogenization in Fast Reactor Environments

Advanced fast reactor concepts, such as the CFV core (French acronym of “Coeur à Faible effet de Vide Sodium,” meaning “low sodium void effect core”), are characterized by a heterogeneous axial core arrangement, with an inner fertile zone and a sodium plenum above the fuel. Such concepts represent a strong challenge for accurate predictions of the control-rod antireactivity effects, and the surrounding local fuel pin power. Classical equivalence procedures, which were developed for axially homogeneous cores, are put to the test when applied to such axially heterogeneous cores.In this work, we investigate the influence of variations in the local neutron spectra, for different control-rod environments, with the objective of understanding the impact of spectral variations in control-rod homogenization. This was conducted by considering a simple one-dimensional model of the equivalence procedure in which a transition zone between the fuel and control rod was introduced to represent different control-rod environments.Two types of situations were studied, one corresponding to softened neutron spectrum environments, for which the impact in the homogenized control-rod cross section was found to be smaller than 5%. The second situation was with wide elastic scattering resonances in the control-rod environment, which could locally lead to differences of up to 15% in the resulting equivalent cross sections. The reactivity effect of these changes was calculated to be less than 2%.In some cases, the numerical stability of the equivalence procedure was adversely affected, mainly in high-energy groups, due to the softening of the neutron spectra.

Periodicity of reproductive growth in lycopsids: An example from the Upper Devonian of Zhejiang Province, China

Monilistrobus Wang et Berry is a fossil lycopsid reported from the Upper Devonian Wutong Formation of Jiangsu Province, China, and includes only the type species Monilistrobus yixingensis Wang et Berry. Along a single fertile axis, Monilistrobus has cone-like structures separated by and alternated with a length of vegetative region, which is an important character here termed as periodicity of reproductive growth. The alternation of fertile and vegetative growth occurs regularly and produces repeated intercalary (non-terminal) fertile zones. New specimens, identified as Monilistrobus cf. yixingensis, from the same formation but of Zhejiang Province extend the geographic distribution of this genus. These new specimens demonstrate morphological variations within this genus, such as the lack of spiny appendages on the leaves, different measurements of leaf bases, and different shapes and positions of cone-like structures. The distribution of intercalary fertile zones, as summarized for the first time in this paper, occurs in the Drepanophycales, the Protolepidodendrales, the Isoëtales, the Lycopodiales, the Selaginellales, and Wuxia Berry, Wang et Cai and Monilistrobus of uncertain affinities. Thus, this peculiar trait might have evolved in the very early evolutionary stage of the lycopsids, as indicated in the basal group Drepanophycales. However, the presence of repeated, two or more intercalary fertile zones along a single fertile axis is demonstrated only in Monilistrobus and the extant Huperzia Bernhardi.

Innovation in a Small State: Qatar and the IBC Cluster Model of Higher Education

Innovation in a Small State: <scp>Q</scp>atar and the <scp>IBC</scp> Cluster Model of Higher Education

Using Diverse Sources of Evidence for Reconstructing the Past History of Musical Exchanges in the Indian Ocean

Although the Indian Ocean has long been recognised as a fertile zone for cultural exchange, reflecting both trade routes and colonisation, it is only now coming into prominence in terms of its significance for the past history of the continents around its rim. It is now accepted that economic plants, animals, diseases, trade goods, languages, religion and cultural elements all moved around and across the Indian Ocean, often transforming the societies and environments into which they were introduced. The paper explores one specific aspect of cultural exchange, music and musical practice in the Indian Ocean. Case studies are used to assess the value and significance of different categories of evidence for the reconstruction of musical history and the resultant chronostratigraphy. These include the history of two types of zither which occur on both sides of the Indian Ocean and which attest to the significance of geographical distributions of material culture. A related issue is the vexed question of the similarities of the xylophone in Southeast Asia and Africa and the role of morphology in resolving the historical direction of transfer. Slavery and the African diaspora in the Indian Ocean have only recently been the subject of in-depth scholarly examination, and the paper summarises current literature and begins the process of categorising the exchange of musical subcultures. This throws into focus an important aspect of maritime transfers in the Indian Ocean: the low profile of some of the great trading nations, such as the Sassanians and the Chinese, in terms of cultural influence, despite their importance in overall trade. The paper suggests that disease and a focus on trade to the exclusion of other activities may account for this disparity.

Sporophyll organization in the Triassic isoetalean lycopsid Lepacyclotes (formerly Annalepis) zeilleri from Germany

Annalepis zeilleri is one of the most frequently recorded Middle Triassic lycopsid fossils in central Europe and China. The taxon includes tongue-shaped sporophylls with a blunt to mucronate apex and an adaxial sporangium. However, little is known about the arrangement of the sporophylls and the morphology of the plant that produced them. Specimens from the Middle Triassic of Germany consist of wide axes in cross section surrounded by tightly clustered A. zeilleri sporophylls. This suggests that the sporophylls were produced in a strobilus or in intercalary fertile zones along an axis. Moreover, the fossils correspond in structure to certain other Triassic lycopsid remains that are described as Lepacyclotes circularis and L. bechstaedtii; they thus strengthen the concept that Annalepis and Lepacyclotes are congeneric. Since Lepacyclotes has priority over Annalepis, Lepacyclotes zeilleri is the correct name for the taxon.

The gynoecium structure in Dracaena fragrans (L.) Ker Gawl., Sansevieria parva N.E. Brown and S. trifasciata Prain (Asparagaceae) with special emphasis on the structure of the septal nectary

In the gynoecium of &lt;em&gt;Dracaena fragrans&lt;/em&gt;, &lt;em&gt;Sansevieria&lt;/em&gt; &lt;em&gt;parva &lt;/em&gt;and &lt;em&gt;S. trifasciata&lt;/em&gt;, the vertical zonality of the ovary, the structural zonality of the gynoecium following Leinfellner, and the zonality of the septal nectary were studied. The ovary structure is characterised by a high parenchymatous ovary base and ovary roof as well as a long septal nectary that can be extended in both of them and opens with secretory nectary splits. The gynoecium of these species has a short synascidiate zone, a fertile hemisynascidiate zone with a median ovule attached, a hemisymlicate zone (only in &lt;em&gt;D. fragrans&lt;/em&gt;) and an asymplicate zone (with postgenitally fused carpels) that comprises the ovary roof, common style and stigma. In the septal nectary, we detected three vertical zones: the basal zone of the distinct nectary in the ovary base or/and the synascidiate zone, the zone of the common nectary (in the hemisynascidiate and hemisymlicate zones) and the zone of the external nectary (the nectary splits in the asymplicate zone). The gynoecium structure in the studied species shows differences in the length of the gynoecium and septal nectary zones and also in the interrelationships of all these three types of vertical zonality.

Moral Play and Counterpublic: Transformations in Moral Drama, 1465-1599 by Ineke Murakami

Ineke Murakami. Moral Play and Counterpublic: Transformations in Moral Drama, 1465-1599. volume 18 of routledge studies in renaissance Literature and Culture. New York: routledge, 2011. 247 pages. $141.Reviewed by Jennifer R. RustIneke Murakami's Moral Play and Counterpublic: Transformations in Moral Drama, 1465-1599 testifies to vitality of tradition in fif- teenth and england. it is a significant contribution to schol- arship on pre-shakespearean drama, particularly in its attention to continu- ities between late-medieval drama (represented by initial chapter's analysis of fifteenth-century Mankind) and flourishing professional theater of later sixteenth century (addressed in concluding chapters on Marlowe and Jonson). Murakami argues that dramatic allegories of moral plays are so- phisticated discourses that enable new forms of consciousness. she elaborates this claim with ambitious theoretical forays, drawing upon Marx- ism, psychoanalysis, and biopolitics to explicate breadth of cultural and social work performed by these dramas. in addition to providing a new per- spective on english tradition of moral drama, Moral Play and Counterpublic makes a meaningful intervention in growing body of critical work on early modern spheres.In Murakami's introduction, interrelation between the genre of mo- rality and emergence of diverse sixteenth-century spheres is posited as unifying principle (4) of study. Murakami favors Michael warner's formulation of over Jurgen Habermas's much- critiqued account of public sphere as primarily an eighteenth-century bourgeois phenomenon. warner's concept of counterpublics originally the- orized relations between, on one hand, discourses produced by marginalized collectivities and, on other, a dominant discourse in contemporary American culture. Nonetheless, Murakami finds this concept to be apt to describe kinds of publics that emerge in conjunction with early modern theatrical performance, particularly their ephemeral, non- elite and often agonistic (12), anti-authoritarian characteristics. Murakami further builds on steven Mullaney's contention that early modern theater was a particularly fertile zone for producing publics: [a]s a particularly hybrid me- dium that partakes of several modes of publication at once . . . drama constitutes a mode of publicity that 'precipitates new forms of critical and aes- thetic thinking about . . . relation between theatre and commonwealth' (13). Murakami is particularly concerned to illuminate hybrid nature of moral play itself, as a discursive tradition that moved both within and outside authoritative institutions without collapsing into either propaganda or politically radical ideology (13). Moral plays were particularly adept at so- liciting counterpublics because they activated among their audiences a faculty for judgment-of not only aesthetic quality of play but also its po- litical and social dimensions (14). To further this interpretation, Murakami develops a versatile concept of allegory, which emerges as a polyvalent and dynamic discursive mode that enables moral drama to address political, so- cial, economic, and religious tensions in a flexible and sophisticated manner. Murakami argues that early modern moral plays are best understood through this multifaceted, fluid conception of allegory, which liberates these dramas from some of more stultifying homiletic interpretations to which they have been subjected in past.Acknowledging that legible evidence of counterpublics generated by early modern moral plays is often hard to discern, Murakami nonetheless in- sists that a careful analysis of historical and literary documents will allow one to extrapolate publics(15) that moral plays both invited and sum- moned into being. …

Core design options for high conversion BWRs operating in Th–233U fuel cycle

Several options of fuel assembly design are investigated for a BWR core operating in a closed self-sustainable Th–233U fuel cycle. The designs rely on an axially heterogeneous fuel assembly structure consisting of a single axial fissile zone “sandwiched” between two fertile blanket zones, in order to improve fertile to fissile conversion ratio. The main objective of the study was to identify the most promising assembly design parameters, dimensions of fissile and fertile zones, for achieving net breeding of 233U. The design challenge, in this respect, is that the fuel breeding potential is at odds with axial power peaking and the core minimum critical power ratio (CPR), hence limiting the maximum achievable core power rating.Calculations were performed with the BGCore system, which consists of the MCNP code coupled with fuel depletion and thermo-hydraulic feedback modules. A single 3-dimensional fuel assembly having reflective radial boundaries was modeled applying simplified restrictions on the maximum centerline fuel temperature and the CPR. It was found that axially heterogeneous fuel assembly design with a single fissile zone can potentially achieve net breeding, while matching conventional BWR core power rating under certain restrictions to the core loading pattern design.

Reconfiguring the Dunes

Here the sand deserts of Mui Ne, one of the most cliché sights in the Vietnamese image-world, are considered in their lived and representational use as spaces with a sustaining and forceful visual presence and practice in different political moments. Their geographical location and geo-embodiments, their persisting status as an icon and a ritual of Vietnamese photography, and their current value as a thriving tourist venue, make them an ideal and fertile zone to register changing modes of Vietnamese identity, history and subjectivity visibly.

Reproductive Organs and In Situ Spores of Asteroxylon mackiei Kidston &amp; Lang, the Most Complex Plant from the Lower Devonian Rhynie Chert

Asteroxylon mackiei is the largest and most complex vascular land plant from the Lower Devonian Rhynie Chert. Fertile remains were first reported nearly 40 years after the description of the sterile axes but were not described in greater detail. In this contribution, we document several fertile axes from longitudinal and transverse thin sections. Sporangia, consisting of two kidney-shaped valves, are interspersed among the nonvascularized leaflike appendages and attached to the axis with a short pedicel. The sporangia are curved and lie close to the axis. Sporangia possess a dome-shaped central structure that forms the continuation of the short stalk into the sporangial cavity. The in situ spores are identified as Retusotriletes cf. triangulatus. The sporangia were apparently abscised after sporulation. Fertile zones with leaflike appendages and sporangia alternate with sterile zones with only leaflike appendages within an axis, suggesting a periodicity of growth.