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The Azraq oasis in the Eastern Desert of Jordan has produced considerable stone artefacts attributed to the early Palaeolithic, yet relatively few data are available regarding the chronology and palaeoenvironmental contexts of the remains. In this study, we present stratigraphic, sedimentological, and micropalaeontological analyses of the Late Acheulean site SM1 located within the former Shishan Marsh, which we combine with geochronological and sedimentological data from 13 neighbouring geological exposures to reconstruct landscape evolution at the western margin of the Shishan Marsh. We then discuss the Late Quaternary palaeolandscapes of the Greater Azraq Oasis Area over the past c. 350 ka. Our work demonstrates that the central Azraq Basin experienced three local wetting-drying cycles since the late Middle Pleistocene that would have dramatically shifted the quantity and distribution of freshwater resources, ranging from expansive wetland landscapes to desert refugia characterised by isolated spring pools—changes that would have significantly impacted the mobility decisions and settlement patterns of Palaeolithic inhabitants. Our study highlights that developing long-term records of human-environment dynamics in arid environments requires a mosaic approach to palaeoenvironmental reconstruction that is nested within a well-developed understanding of landscape evolution.

Recently, Zhang et al. proposed a lattice-based data outsourcing scheme with public integrity verification (DOPIV), which enables an original data owner to delegate a proxy to generate the signatures of data and outsource them to the cloud server. They employed a third party auditor (TPA) to check the integrity of the outsourced data and any TPA can verify the data integrity efficiently. Besides, DOPIV is claimed to achieve proxy-oriented secure data outsourcing as well as storage correctness guarantee. Unfortunately, we find that there may exist vulnerabilities in DOPIV which allows the cloud server to simply delete the received data without being noticed by the TPA. Fortunately, we have come up with a simple and efficient solution to thwart the proposed attack and our improved scheme maintains all the features claimed in DOPIV.

Federated learning can achieve the purpose of distributed machine learning without sharing privacy and sensitive data of end devices. However, high concurrent access to the server increases the transmission delay of model updates, and the local model may be an unnecessary model with the opposite gradient from the global model, thus incurring a large number of additional communication costs. To this end, we study a framework of edge-based communication optimization to reduce the number of end devices directly connected to the server while avoiding uploading unnecessary local updates. Specifically, we cluster devices in the same network location and deploy mobile edge nodes in different network locations to serve as hubs for cloud and end devices communications, thereby avoiding the latency associated with high server concurrency. Meanwhile, we propose a model cleaning method based on cosine similarity. If the value of similarity is less than a preset threshold, the local update will not be uploaded to the mobile edge nodes, thus avoid unnecessary communication. Experimental results show that compared with traditional federated learning, the proposed scheme reduces the number of local updates by 60%, and accelerates the convergence speed of the regression model by 10.3%.

Materially plastics are ambivalent. In spite of their often lauded quality of creating seemingly untethered imitations, representations and replacements, they have a materiality that leaks, off-gasses and disintegrates. They are accomplished at mimicry yet frequently unable to be remoulded. They are ostensibly resistant to microbial contamination yet absorb environmental pollutants and leach endocrine disrupting plasticisers. This article argues that, due to the material influence of plastics, their ubiquity, and the societal transformations that they have enabled, that anthropologists need to pay sustained attention to this material. Moreover, it argues that anthropological methods and theories are crucial to understanding plastics at a vital moment in their (and our) history. It articulates three ways in which anthropology can engage plastics at all stages in their lifecycles. Firstly, to study plastics challenges what it means to exist: whether or not human beings are bounded or permeable entities, experienced as individuated, collective or somewhere in between. Secondly, plastics disrupt what people know, are willing to know, or are persuaded is worth knowing about the production and disposal of the products that they consume. Thirdly, the materiality of plastics expose contemporary inequalities. Plastics can create unseen violence, both in their geographically unequal toxic distributions and in the vastness of their temporal effects.

We show that simple modifications to van der Hoeven's forward and inverse truncated Fourier transforms allow the algorithms to be performed in-place, and with only a linear overhead in complexity.

Hybrid renewable energy systems (HRES) are seeing as a solution to overcome the fluctuation and randomness of certain renewable energy sources, such as solar and wind power. Coupling the fluctuating renewable energy sources with the controllable sources, such as biomass-fueled micro-cogeneration, constitute an HRES that significantly reduces CO2 emissions and primary energy consumption. The purpose of this work is to review research works on hybrid renewable energy systems based on micro-cogeneration and to present a case study of optimizing a solar-based micro-cogeneration system. First, renewable energy-fueled micro-cogeneration systems are presented according to the prime mover technology: Stirling engine, organic Rankine cycle and photovoltaic-thermal (PVT). The different prime movers are assessed according to their advantages, disadvantages and market availability. Next, several research works on hybrid renewable energy systems including solar and micro-cogeneration technologies are summarized and key findings are highlighted. Finally, the results of the case study are presented for reasoning the necessity of system hybridization. The results indicated that more experimental data on HRES and research effort on energy management strategies and stochastic optimization models are required. The results of the case study showed maximum thermal and electrical reliability of 68% and 70%, respectively. The optimized PVT/battery/thermal storage system was not able to cover all energy demand of the case study but supporting heat and electricity sources are required.

The digital humanities (DH) is an emerging field of teaching and research that invites modern technologies to address traditional humanities questions while simultaneously making space for humanistic critiques of those technologies. A natural relationship exists between DH and the field of information studies (the iField), particularly surrounding their common focus on the interface between humans and computers, as well as subfields such as the organization of information, libraries and archives, data preservation, and information in society. Thus, we propose that iField programs in universities should take an active role in DH education. We are particularly interested in programs that are officially Information Schools (iSchools), members of the international iSchools Organization. Our research began as part of a DH curriculum committee convened by the iSchools Organization. To support iSchool engagement in DH education, we have inventoried and analyzed the degrees and supplemental credentials offered by DH education programs throughout the world. Our study deployed multiple data collection methods, which included conducting both ad hoc and comprehensive website surveys, querying an online DH catalog, and inviting members of the iSchools Organization to participate in an online questionnaire. This work has revealed several common patterns for the current structure of DH programs, including the various types of degrees or supplemental credentials offered. We observe that iSchools have a significant opportunity to become more engaged in DH education and we suggest several possible approaches based on our research.

Canteen Kopje was a prominent location within the spread of nineteenth century mining camps at Klipdrift along the Vaal River. This article presents the results of excavation of the historical component of Canteen Kopje that produced an artifact assemblage in which European manufactured ceramics and glass are associated with objects of local manufacture, which attests to the cultural interaction that took place in the context of early mining. These finds of material culture are associated with a faunal assemblage of wild animals primarily the remains of quagga, a species that was soon to go in extinct. Based on historical documentation and pictorial representation it is argued that the earliest Vaal River diamond diggings here represent a stage of extractive economies in southern Africa when the rigid control of space and people that emerged subsequently was not yet fully developed.

The emergence of Body Area Networks (BANs) has paved the way for real-time sensing of human biometrics in addition to remote control of smart wireless medical devices, which in turn are beginning to revolutionize the smart healthcare industry. However, due to their limited power and computational capabilities they are vulnerable to a myriad of security attacks. To secure BAN sensors against these threats processor-intensive cryptographic techniques need to be avoided as they are not suitable in this context. This paper focuses on authentication service for BAN sensors and proposes an original scheme named "RAFV: Rotational Assisted Fuzzy Vaults" to harden the security of any authentication solution using the fuzzy vault construction approach. The evaluation results have shown that RAFV can successfully conceal the secret of the vault even if the locking elements are known to the adversary. Also, RAFV may improve upon communication overhead by enabling a reduction in the size of the vault without compromising its security. It has achieved all of this while remaining competitive with regards to additional computational overhead.

Micro-stamping is a promising process for the low-cost manufacture of micro-channels from thin metal sheet for fuel cell bipolar plates. Most previous studies numerically analysed micro-stamping processes by assuming a perfect tool profile and position. In this work, thin 316 L stainless steel sheet is stamped with a micro-stamping tool to produce micro-channels and the initiation of fracture is experimentally investigated. Severe material thinning and fracture were observed in locations where the sheet contacts the tool and related to tool misalignment and profile inaccuracies that only could be identified with a 3D profilometer and an optical microscope. A 2D finite element model of the process was then developed and showed that, to accurately represent material thinning and forming limits in the micro-stamping of the stainless steel sheet, the scanned tool profile shape and position need to be accounted for. Comparison with the experimental Forming Limit Diagram (FLD) suggests that in the stamping of micro-channels from thin stainless steel sheet, material failure is governed by the development of a neck and therefore can be successfully assessed by the FLD.

In cloud storage, how to search sensitive data efficiently and securely is a challenging problem. The searchable encryption technique provides a secure storage method without loss of data confidentiality and utilization. As an important branch of searchable encryption, public-key encryption with keyword search (PEKS) is widely studied by scholars. However, most of the traditional PEKS schemes are vulnerable to the inside keyword guessing attack (IKGA) or some other weaknesses. Resisting the inside keyword guessing attack is likely to become a must-have property of all new PEKS schemes. For a long time, mitigating IKGA has been inefficient and difficult, and thus most existing PEKS schemes fail in achieving their security goals. To improve the security and efficiency of PEKS, we define the notion of Dual-server Public-key Authenticated Encryption with Keyword Search (DPAEKS), which protects against IKGA with high computation efficiency, and supports the authentication property. Then, we provide a construction of DPAEKS without bilinear pairings, which is secure against IKGA by leveraging two servers that do not cooperate. Experimental results obtained using a real-world dataset show that our scheme is highly efficient and provides strong security, making it suitable for deployment in practical applications.

The main factor restricting lead isotope analysis of metals from museum collections is the requirement for physical material. Hence, there are major incentives for developing minimally invasive methods for lead isotope analysis that are accurate and precise enough to reveal historical information about artefacts and their origin. Portable laser ablation (pLA), collecting microscopic samples on Teflon filters, has four key benefits. It produces no visual impact to the artefacts, does not require transport of artefacts to laboratory facilities, there are no artefact size restrictions, and samples are processed under clean laboratory conditions allowing Pb purification prior to measurement by solution MC-ICPMS. To validate the efficacy of the pLA technique on silver, nine matrixed-matched commercial, in-house and archaeological reference materials were sampled and analysed multiple times (9-10). The pLA mean analyses (±2SD) were all consistent with inter-laboratory bulk analyses. The digestion of sample filters produces precisions that are consistently more than five-times better than in situ nsLA-MC-ICPMS and are the same order of magnitude expected for bulk samples processed in different laboratories. This journal is

This paper aims to illustrate and give an interpretation of the results emerged from a pilot activity developed within the ROCK project, by the Department of Architecture of the University of Bologna, Alma Mater Studiorum. Through this activity, we studied the indoor microclimate of the University Library of Bologna (BUB), in the Archive and in the Lecture Hall, with the aim to detect how these spaces are affected by the influence of factors such as the outdoor climate and the cooling and heating systems. Moreover, the paper presents the customisation of the probes’ alert system and of the probes itself, used for a one-year monitoring campaign started on the 20th of December 2018. In addition, we calculated the Heritage Microclimate Risk index, to verify the level of risk to which the heritage in the Library is exposed due to the indoor microclimate, and the Predicted Risk of Damage index, that evaluate the more specific risks of damage to which precise objects hosted in there are exposed. Therefore, this paper enriches the research field of Historic Indoor Microclimate, started in 2013, which concerns issues as preventive conservation and restoration in historic buildings. The new insights about the Bologna University Library facilitate the possibility to draw up a specific ‘Indoor Microclimate Management Protocol (IMMP)’ aimed at the preventive conservation of manuscripts and books in historical libraries.

This essay reviews the following works: Ancient Maya Pottery: Classification, Analysis, and Interpretation. Edited by James John Aimers. Gainesville: University Press of Florida, 2013. Pp. vii + 293. $79.95 cloth. ISBN: 9780813042367. The Huasteca: Culture, History, and Interregional Exchange. Edited by Katherine A. Faust and Kim N. Richter. Norman: University of Oklahoma Press, 2015. Pp. vii + 241. $55.00 cloth. ISBN: 9780806147048. Excavations in Residential Areas of Tikal: Group 7F-1. By William A. Haviland. Philadelphia: University of Pennsylvania Museum of Archaeology and Anthropology, 2015. Pp. xi + 133. $65.00 cloth. ISBN: 9781934536810. Politics of the Maya Court: Hierarchy and Change in the Late Classic Period. By Sarah E. Jackson. Norman: University of Oklahoma Press, 2013. Pp. ix + 248. $29.95 hardback. ISBN: 9780806143415. The Ancient Maya Marketplace: The Archaeology of Transient Space. Edited by Eleanor M. King. Tucson: University of Arizona Press, 2015. Pp. vii + 325. $60.54 cloth. ISBN: 9780816500413. The Spectacle of the Late Maya Court: Reflections on the Murals of Bonampak. By Mary Miller and Claudia Brittenham. Austin: University of Texas Press, 2013. Pp. xi + 285. $54.05 cloth. ISBN: 9780292744363. Maya Lords and Lordship: The Formation of Colonial Society in Yucatan, 1350–1600. By Sergio Quezada. Translated by Terry Rugeley. Norman: University of Oklahoma Press, 2014. Pp. ix + 248. $34.95 cloth. ISBN: 9780806144221. Place and Identity in Classic Maya Narratives. By Alexandre Tokovinine. Washington, DC: Dumbarton Oaks Research Library and Collection/Harvard University Press, 2015. Pp. vii + 180. $39.95 paperback. ISBN: 9780884023920.

This study focuses on literary and sub-literary texts which present Egyptian scholars. I first look at outsider’s views (like the church-father Clement of Alexandria), borderline views (like the Egyptian priest Chairemon), and insider’s views. For the latter examination, two compositions are studied in more detail. The first is the Book of the Temple, which is a manual of the ideal Egyptian temple, including sections about the duties of several of its intellectual specialists. The second is the Ritual for Entering the Chamber of Darkness, which is a difficult text about the initiation to arcane religious knowledge and the mysteries of writing.

Approximately 90% of Mexican archaeological sites are on communal ejido lands and yet the Mexican Constitution stipulates that all cultural heritage is the property of the federal government. Considering this disconnect between federal and local practices, how can archaeologists work with ejido communities to help preserve cultural patrimony? This article explores the micropolitics associated with archaeological fieldwork on communal ejido lands in Western Mexico. We show how long-standing practices based on local histories, community political theater, and interpersonal relations shape fieldwork and cultural conservation initiatives in important and unintended ways. In our study near the site of Angamuco, Michoacán, we draw upon ethnographic and archival research and outreach projects over five field seasons, and address the tensions that emerge when informal micropolitical and formal top–down sociopolitical practices interface. We show how aspects of a policy science approach are appropriate for long-term community-supported archaeology and cultural heritage management.

Le Finistere a fait l’objet de nombreuses campagnes de prospections au sol, depuis les annees 1970, jusqu’a aujourd’hui. Entre les seminaires de terrain conduits par P. Gouletquer et les prospections coordonnees par Y. Bougio plus recemment, ce sont environ 1 318 sites prehistoriques qui ont ete decouverts, dont 130 ont ete attribues au Mesolithique. Plusieurs sondages ainsi que deux fouilles ont accompagne ce travail, nous permettant de mieux comprendre l’occupation du territoire au Mesolithique. Parallelement, les prospections continuent, que ce soit dans le cadre d’un programme de recherche sur les abris, ou de facon plus independante par des archeologues « amateurs ». Ainsi, 22 sites, dont l’attribution varie entre Mesolithique et Neolithique, ont ete decouverts recemment par D. Duvollet, dans le Finistere sud, avec cinq sites inedits particulierement remarquables : Keramperchec (Rosporden), Treganan (Scaer), le Run 2 (Melgven), Le Cosquer (Melgven) et Livinot (Bannalec). L’examen de ces collections est l’occasion de faire une synthese sur le Mesolithique cornouaillais, encore jamais realisee malgre de nombreux travaux de terrain et monographies. En plus des sites mis au jour par D. Duvollet, les prospections de Y. Bougio seront egalement integrees a ce travail, afin de mieux comprendre les modalites d’occupation de cet espace geographique. Dans cet article, nous procederons alors a une description des collections issues d’occupations inedites, afin d’aborder les questions de l’approvisionnement en matiere premiere, de l’economie du debitage mais aussi de la circulation potentielle des populations et de leurs idees.

Cette note de recherche en cours examine les tensions entre les instances politiques et les institutions littéraires à l’origine du processus de patrimonialisation de la littérature camerounaise des années 1950 à 1980. Par patrimonialisation du fait littéraire au Cameroun, on entend les modes de formation des classiques étudiés sous deux points de vue : d’une part la consécration des œuvres et leur pérennisation dans le paysage littéraire, et d’autre part les imaginaires autour des auteurs qu...

International audience; Abstract The purpose of this article is to present an inventory of certain faunal remains from Linearbandkeramic (LBK) settlements in the Paris Basin (Ile-de-France, Hauts-de-France and Champagne) that seem to belong to a particular category, that of “sign-objects,” in other words, tangible evidence intended to be shown and directly interpretable by an observer belonging to the society which produced them. Based on three categories of archaeological contexts, a ceremonial enclosure, settlements and graves, we will attempt to highlight the species that were important to Neolithic society. Two of them, the domestic cattle and the aurochs, are particularly involved in the deposits through the exhibition of their bones or their horn cores. Sheep and roe deer are also involved through, for example, transformed bones such as perforated tibias or sharpened roe deer antlers. The results of the analysis were integrated into an archaeological model previously developed to approach the social structure of the Neolithic society.; L’objectif de cet article est d’examiner des éléments osseux peu transformés, datés de la Céramique Linéaire (LBK) et provenant de sites fouillés du Néolithique ancien (5100-4700 av. n.è.) dans le Bassin parisien, qui nous paraissent appartenir à une catégorie qui peut être qualifiée « d’objets-signes », c’est-à-dire directement interprétables par un observateur de la société qui les produit. L’étude a été menée en partant de la faune trouvée dans l’enceinte de Menneville ainsi que celle provenant de sépultures, puis en cherchant à retrouver des objets-signes dans 22 villages contemporains d’Ile-de-France, des Hauts de France et de Champagne. Les analyses menées mettent en évidence des ossements particuliers issus d’animaux domestiques ou sauvages qui sont exposés au moment de cérémonies impliquant des sacrifices d’animaux, ou qui se retrouvent dans certaines maisons. Dans l’enceinte, certains os de bovins, des bucranes et des chevilles osseuses sont sélectionnés et déposés isolément, alors que les membres en connexion proviennent de moutons, de porcs ou de chiens. Dans les habitats, un lien entre certaines catégories d’ossements et le type de maison est perceptible. Dans les grandes maisons on répertorie des chevilles osseuses ou bucranes de bovins entiers, des os d’aurochs en nombre important, des tibias perforés de mouton et des bois de chevreuils appointés. Les crânes ou les pattes d’animaux sauvages rares et les tibias de chevreuils perforés sont à l’inverse dans les maisons de petite taille. Une réflexion est menée à partir de ces résultats pour les intégrer à un modèle archéologique et les confronter à des éléments de l’anthropologie qui s’est penchée sur la signification des objets-signes de différentes natures et en tirer des hypothèses pour la société néolithique.

Objective The present study explores growth and health in Roman (1st-3rd centuries CE) and Post-Roman (4th-7th centuries CE) Gaul, incorporating a life-course approach, to better understand the influence of Roman practices and lifestyles on health, and the impact of cultural change from the Roman to the Post-Roman period. Materials and Methods The skeletal remains of 844 individuals were analyzed for non-specific signs of physiological stress, including growth disruption (diaphyseal and adult maximum femur length), dental enamel hypoplastic defects (DEH), cribra orbitalia (CO), and periosteal reaction of the tibiae (Tibia PR). Results The Gallo-Roman sample demonstrated shorter femoral lengths, and higher rates of DEH and Tibia PR. Post-Roman groups demonstrated longer femoral lengths and higher rates of CO. Conclusions Gallo-Roman individuals may have been more regularly exposed to infectious pathogens throughout childhood, inhibiting opportunities for catch-up growth, resulting in high rates of DEH and shorter femoral lengths (‘intermittent stress of low lethality’). This could be the result of overcrowding and insalubrious urban environments. Higher rates of CO in the Post-Roman samples may have been influenced by dietary changes between the periods. Significance The intertwined and often synergistic relationships between early life environment, nutrition and settlement structure is highlighted, helping to further understandings of life experiences during the Roman and Post-Roman periods. Limitations It was not possible to obtain sufficient data from northern regions during the Gallo-Roman period, limiting this analysis. Suggestions for Further Research Further application of life course approaches can reveal subtle patterns in stress indicators.

The Washington Arms Limitation Treaty 1922 was arguably one the most significant disarmament treaties of the first half of the 20th century. It can be shown that the heritage items associated with this treaty are still extant. Ship&rsquo, s bells are one of the few moveable objects that are specific to the operational life of a ship and are therefore highly symbolic in representing a vessel. This paper surveys which bells of the ships scrapped under conditions of the Washington Arms Limitation Treaty are known to exist. A typology of ship&rsquo, s bells has been developed to understand the nature of bell provisioning to vessels newly commissioned into the U.S. Navy. Each of the countries associated with the Washington Treaty have divergent disposal practices with respect to navy property, and this is reflected in both the prevalence and nature of custodianship of ship&rsquo, s bells from this period. Such procedures range from the U.S. requirement commanding all surplus Navy property to be deemed government property upon ship deactivation, to the British practice of vending ship&rsquo, s bells to private parties at public sales. However, ship&rsquo, s bells, like many obsolete functional items, can be regarded as iconic in terms of heritage and therefore warrant attention for future preservation and presentation in the public domain.

Sorption thermal battery has revealed vast potential of heat utilization to address the issue of long-term energy storage. A hybrid compression-assisted sorption thermal battery is presented for solar energy utilization, which aims to solve the mismatch of heat storage and supply in cold region. Thermodynamic performance of the hybrid sorption thermal battery in cold region is analyzed by using MnCl2–SrCl2 and MnCl2–CaCl2 working pairs and then compared with that of basic sorption type with internal heat recovery. It is demonstrated that when ambient temperature in winter ranges from −30 °C to -5 °C, energy and exergy efficiencies of hybrid thermal battery using different working pairs increase from 0.74 to 0.865 and 0.25 to 0.43, respectively. Energy efficiency of hybrid thermal battery is almost twice higher than that of basic type with internal heat recovery. For different operating parameters, mass ratio and global conversion rate have a larger influence on thermal performance than isentropic efficiency of compressor. Although energy storage density per salt of basic sorption thermal battery is a bit higher than that of hybrid type, the density per reactor of hybrid compression-assisted thermal battery could be improved by 50%, which indicates a good system compactness in real application.

Before Europeans arrived to Eastern North America, prehistoric, indigenous peoples experienced a number of changes that culminated in the development of sedentary, maize agricultural lifeways of varying complexity. Inherent to these lifeways were several triggers of social stress including population nucleation and increase, intergroup conflict (warfare), and increased territoriality. Here, we examine whether this period of social stress co-varied with deadlier weaponry, specifically, the design of the most commonly found prehistoric archery component in late pre-contact North America: triangular stone arrow tips (TSAT). The examination of modern metal or carbon projectiles, arrows, and arrowheads has demonstrated that smaller arrow tips penetrate deeper into a target than do larger ones. We first experimentally confirm that this relationship applies to arrow tips made from stone hafted onto shafts made from wood. We then statistically assess a large sample (n = 742) of late pre-contact TSAT and show that these specimens are extraordinarily small. Thus, by miniaturizing their arrow tips, prehistoric people in Eastern North America optimized their projectile weaponry for maximum penetration and killing power in warfare and hunting. Finally, we verify that these functional advantages were selected across environmental and cultural boundaries. Thus, while we cannot and should not rule out stochastic, production economizing, or non-adaptive cultural processes as an explanation for TSAT, overall our results are consistent with the hypothesis that broad, socially stressful demographic changes in late pre-contact Eastern North America resulted in the miniaturization–and augmented lethality–of stone tools across the region.

Bereits vor einem halben Jahrhundert hat Michel Foucault in seiner Ordnung der Dinge auf die Willkür und Macht von Ordnungssystemen hingewiesen. Dieser Beitrag versucht, Vorschläge für ein neues dialogisches Format zur Konzeption einer globalen Bibliothek zu machen, die von und mit dem, was in einem Ordnungssystem als „randständig“ in einem anderen jedoch „zentral“ erscheinen mag, gedacht wird. Diese globale Bibliothek als „geteiltes“ und nicht mehr „hierarchisiertes“ Welterbe setzt eine neue Sprache, neue Vokabularien voraus, die nicht nur diachron sondern auch diatopisch angelegt sind, und also immer bereits aus einer transkulturellen Perspektive betrachtet werden, die es erlaubt, die transformative Kraft von kulturellem Transfer konstruktiv und kreativ zu nutzen. Already half a century ago, Michel Foucault in his Order of Things pointed to the arbitrary might of systems of classification and order. This essay proposes a new dialogical format for the conception of a global library that is thought in conjunction with what may appear to be "marginal" in one system of order but "central" in another. This global library as a "shared" and no longer "hierarchised" world heritage presupposes a new language, new vocabularies that are not only diachronic but also diatopic in nature, and thus always already viewed from a transcultural perspective which allows the transformative power of cultural transfer to be used constructively and creatively.

In the course of the human past the elimination of the testicles of boys and men – what we call castration – has taken place for a variety of reasons. Many times it was meant to deliberately hurt people. It is and was also performed, though, as a therapeutic measure by well-meaning physicians. Studying the motivations of medical practitioners involved in castration practices provides insight into the deontology and cultural context of these healers. This article explores the healing activities of the physicians of the ancient Greek and Roman worlds in this special field of surgery. In the extant literary sources we find medical indications for castration which are quite obvious to a modern eye, but also more mysterious and unexpected occasions which need to be explained from the historical context.

Closed-loop geothermal energy recovery technology has advantages of being independent of reservoir fluid and permeability, experiencing less parasitic load from pumps, and being technologically ready and widely used for heat exchange in shallow geothermal systems. Commercial application of closed-loop geothermal technology to deep high-enthalpy systems is now feasible given advances in drilling technology. However, the technology it uses has been questioned due to differences in heat transport capacities of convective flow within the wellbores and conductive flux in the surrounding rock. Here we demonstrate that closed-loop geothermal systems can provide reasonable temperature and heat duty for over 30 years using multiple laterals when installed in a suitable geological setting. Through use of two analytical methods, our results indicate that the closed-loop geothermal system is sensitive to reservoir thermal conductivity that controls the level of outlet temperature and interference between wells over time. The residence time of the fluid in the horizontal section, calculated as a ratio of the lateral length to flow rate, dictates heat transport efficiency. A long vertical production section could cause large drops in fluid temperature in a single lateral production system, but such heat loss can be reduced significantly in a closed-loop system with multiple laterals.

Understanding the flow and heat transfer in fractured geothermal reservoir is critical for the development of enhanced geothermal system (EGS) in the future. Under the framework of discrete fracture network, a thermal-hydraulic coupled model is proposed to evaluate the heat extraction performance of multilateral wells in fractured reservoirs. Five cases with varying numbers of branch wells considering well orientation are compared. In addition, we analyze the heat extraction performance response of multilateral wells in fractured reservoirs to the operating parameters. Results demonstrate the minimal effect of the increasing number of branch wells on the production temperature, while impacts on the well pressure are much greater. The injection pressure is observed to decrease significantly as the number of branch wells increases, resulting in a reduced reservoir flow resistance and increased net thermal energy by reducing pump energy consumption. For the same case, increasing the number of intersections between wells and fractures reduces the production temperature and injection pressure. Parameter sensitivity analysis reveals heat production to increases with the mass flow rate, well length and well spacing, and decreases with increasing fracture permeability. This study is expected to provide a view for the application of multilateral wells in fractured geothermal reservoirs.

In the 21st century, climate change is a severe threat to the survival of the planet and humanity; to counter this threat, the significant role of renewable energy cannot be denied for sustainable development worldwide. The motive of this study is to examine the threshold level and asymmetric relationship between renewable energy and economic development in different regimes of the different income levels of 122 countries from 1995-2018 by using the novel technique Panel Smooth Transition Regression Model (PSTR). The results of the PSTR model suggest that the relationship between Renewable Energy and the Economic Growth of these selected countries is nonlinear. Furthermore, in most countries, there is a significant and positive relationship between renewable energy and economic growth in the high regime, except the higher-income nations has a significant and positive relationship in both low and high regimes. Overall full sample shows a significant and positive relationship between renewable energy and economic growth. Recommendations based on this study for these countries include: 1) energy-efficient resources should be adopted to increase renewable energy consumption. 2) The conventional energy consumption share should be reduced to improve the environmental quality for a sustainable future.

The choice of condenser cooling option for concentrating solar power (CSP) plants is likely to affect their techno-economic feasibility. In view of this, an attempt has been made to assess relative techno-economics and net life cycle CO2-eq emissions mitigation (LCCM) potential for 50 MW nominal capacity wet-cooled and dry-cooled parabolic trough solar collector (PTSC) and dry-cooled solar power tower (SPT) based CSP plants with 6.0 h of thermal energy storage for two potential locations in India. It was observed that though dry cooling is likely to save significant amount of water (∼92%) in PTSC based plants, the same shall result in higher capital cost, higher performance penalty and higher parasitic power requirements leading to around 20% higher levelized cost of electricity (LCOE) as compared to wet-cooled PTSC based plants. It was also observed that the dry-cooled SPT based plants shall be able to deliver up to 4.5% higher annual electricity output and LCOE is also likely to be lowered by 13% than wet-cooled PTSC based plants. Considering emissions embodied and emissions associated with water transport/extraction from the source and water treatment, the estimation of LCCM from the PTSC and SPT based CSP plants have also been undertaken.

Ensuring power system reliability under high penetrations of variable renewable energy is a critical task for system operators. In this study, we use a loss of load probability model to estimate the capacity credit of solar photovoltaics and energy storage under increasing penetrations of both technologies, in isolation and in tandem, to offer new understanding on their potential synergistic effects. Increasing penetrations of solar PV alter the net load profile on the grid, shifting the peak net load to hours with little or no solar generation and leading to diminishing capacity credits for each additional increment of solar. However, the presence of solar PV decreases the duration of daily peak demands, thereby allowing energy-limited storage capacity to dispatch electricity during peak demand hours. Thus, solar PV and storage exhibit a symbiotic relationship when used in tandem. We find that solar PV and storage used together make a more significant contribution to system reliability: as much as 40% more of the combined capacity can be counted on during peak demand hours compared to scenarios where the two technologies are deployed separately. Our test case demonstrates the important distinction between winter and summer peaking systems, leading to significantly different seasonal capacity values for solar PV. These findings are timely as utilities replace their aging peaking plants and are taking energy storage into consideration as part of a low carbon pathway.

To enhance the performance of the thermodynamic systems, reduce the pollutants emission to the environment, and decline the fuel utilization, waste heat recovery methods are in high interest. In this paper, a new configuration of an integrated solid oxide fuel cell and gas turbine combined with a biogas reforming cycle is presented for the cogeneration of power and hydrogen. The thermal energy discharged from the SOFC-GT system is used to supply the energy required for the reforming reaction in the biogas reforming cycle for hydrogen production. Comprehensive thermodynamic and thermoeconomic modeling has been performed using EES software. Also, a parametric study has been performed to demonstrate the effect of different parameters on the main performance metrics of the devised system. The results revealed that the energy efficiency and exergy efficiency of the proposed combined system have increased compared to the SOFC-GT system by 23.31 % and 28.19 % , respectively. The net output power and hydrogen production rate are obtained by 2726 kW and 0.07453 kg / s , respectively. From the exergy viewpoint, the afterburner causes a considerable amount of exergy destruction for the system by approximately 26 % of the total exergy destruction rate. Besides, the sensitivity analysis revealed that by increasing the inlet temperature of the fuel cell, the cell voltage reaches a maximum value at a temperature of 679 K and then decreases. Moreover, the total exergy destruction rate and SUCP of the cogeneration system is calculated by 1532 kW and 9400 $ / GJ , respectively.

The Savonius rotor is one of the simple and cost-effective vertical axis drag type devices for hydropower generation. The main drawback of the Savonius hydrokinetic turbine is its low performance due to negative torque developed by returning blade profile. In this paper, the performance of modified V-shaped rotor blades with different V-angles ranging from 90° to 40°, by maintaining fixed edge length, arc radius and aspect ratio of 0.7 is investigated. The numerical analysis is carried out to estimate the optimum V-angle by maintaining 70 mm depth of water with an inlet velocity of 0.3090 m/s. The numerical study revealed that, for 80° V-angle rotor blade profile, the maximum coefficient of power was found to be 0.2279 at a tip speed ratio of 0.9. This optimum V-angle model was used for experimental analysis to study the effect of aspect ratio ranging from 0.7 to 1.75 using top, middle and bottom plates by maintaining 140 mm depth of water and inlet velocity of 0.513 m/s. The rotor blade with two endplates and one middle plate with an aspect ratio of 1.75 has shown a significant increase of performance by 86.13% at a tip speed ratio of 0.86 as compared to turbine blade with two endplates.

In the last few decades, the energy demand is increasing globally which, given the present dependency of the energy generation on fossil fuels, results in a continuous increase in CO2 emissions. In an isolated electric grid system like in the SIDS, the majority of the electricity is produced by fossil fuels, therefore most of the SIDS nations are now focusing on Variable Renewable Energy sources (VREs). VREs such as wind and solar are hardly predictable and bring instabilities in the electric power system if not buffered by a storage system. Here we investigate the possibility of using Seawater Pump Storage Hydropower Systems (S-PSHS) as a renewable energy storage solution in an isolated electric grid. For this, the island of Curacao (one of the SIDS nations) is used as proof of the concept. For detecting potential locations for the S-PSHS sites on the island, GIS application was developed. The application of this conceptual proposed solution in similar systems is straightforward and it can be easily upscaled in other geographies. The concept of using seawater for the pumped hydro project is not common in practice and it is anticipated to have technical, environmental and financial challenges which are discussed in this paper.

Electrocatalytic CO2 reduction (ECO2R) is an environment-friendly way to convert CO2 into profitable products. Amine solution recently has been employed as an electrolyte in ECO2R but suffers from low efficiency. Herein, aqueous solutions containing different amine-based deep eutectic solvents (DESs) were used as electrolytes for CO2 reduction. The effect of different DESs on the CO2 reduction was investigated at Ag, Cu, and Zn metal electrodes. Tafel and electrochemical impedance spectroscopy (EIS) were applied to understand the CO2 reduction. DES in aqueous solution facilitates the CO2 reduction to CO with higher faradaic efficiency of CO (FECO) than amine solutions and a mixture of hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD). Both HBD and HBA have an influence on CO2 reduction. [Monoethanolamine hydrochloride] [methyldiethanolamine] ([MEAHCl][MDEA]) gives high FECO, 71% FECO at −1.1 V vs RHE at Ag electrode, 33% higher than [MEAHCl][MEA]. Experimental results and EIS analysis reveal that the facilitation of CO2 reduction to CO probably stems from a synergistic effect of nano-size agglomerate dispersion on Ag-surface, bicarbonate formation, exchange current density, and Cl− ions present in DESs. These findings present a feasible method to employ the aqueous MDEA-based DES solution as an electrolyte for CO2 reduction.

Fresh green asparagus is prone to lignify after harvest due to its high respiration rate and secretion of secondary metabolites regulated by enzymes generated during storage. In this work, a dense hemicellulose-based coating containing hemicellulose, cellulose nanofibers, and montmorillonite (MMT) was prepared and used as a coating to reduce the respiration rate of green asparagus, with which the shelf life of green asparagus was prolonged from 5 days to 7 days. Alkyl ketene dimer (AKD) was used as a hydrophobizer and a crosslinking agent to reduce humidity sensitivity by introducing hydrophobic fatty acid chains to nanoparticles for increased structural stability and respiratory barrier property hemicellulose-based film in high humidity conditions. Our study proved that AKD modified coating with nature-derived nanomaterials could effectively increase respiratory barrier property, slow down the secretion of lignification-involved enzymes, and regulating the conversion of phenolic compounds to the lignin monomers.

9 figures, 5 tables.-- Supplementary information available, Active and durable electrocatalysts for the oxygen evolution reaction (OER), capable of replacing noble metal catalysts, are required to develop efficient and competitive devices within the frame of the water electrolysis technology for hydrogen production. In this work, we have investigated tantalum based catalysts supported on carbon nanofibers (CNF) for the first time. The effect of CNF characteristics and the catalyst annealing temperature on the electrochemical response for the OER have been analyzed in alkaline environment using a rotating ring disc electrode (RRDE). The best OER activity and oxygen efficiency were found with a highly graphitic CNF, despite its lower surface area, synthesized at 700 °C, and upon a catalyst annealing temperature of 800 °C. The ordering degree of carbon nanofibers favors the production of oxygen in combination with a low oxygen content in tantalum oxides. The most active catalyst exhibited also an excellent durability., The authors want to thank the Ministerio de Economía, Industria y Competitividad (MICINN) and FEDER for the received funding in the project of reference ENE2017-83976-C2-1-R, and to the Gobierno de Aragón (DGA) for the funding to Grupo de Investigación Conversión de Combustibles (T06_17R). J.C. Ruiz-Cornejo acknowledges DGA for his PhD grant. D. Sebastián acknowledges the MICINN for the Ramón y Cajal research contract (RyC-2016-20944).

As a green, low-carbon and renewable energy, the geothermal energy has attracted great attentions. Abundant geothermal resources are hosted in several depleted oilfields. Geothermal development in abandoned oilfields has its advantages that operators are familiar with the geographic environment, geological conditions, and drilling and development techniques in the oilfield. In this study, a thermo-hydro- mechanical multi-field coupling mathematical model was established with data from Liubei Buried Hill reservoir in North China Oilfield. Then, the geothermal development in abandoned high-temperature oilfields was simulated, and the sensitivity of the geothermal development effect to well patterns, fracturing conditions, and working media was analyzed. The results show that the well pattern of one-injector and four-producer leads to the largest heat-exchange area. The hydraulic fracture model causes earlier thermal breakthrough but produces more heat than the non-fractured model. CO2 has the better working fluid performance and leads to the better geothermal development effect than water. This study provides a theoretical basis for the high-efficiency development of geothermal energy in abandoned oilfields, and a guidance for research on geothermal development model and fracturing design.

In the present study, the performance of breakwater-integrated OWC (oscillating water column) wave energy converter devices is analyzed under the action of unidirectional regular and irregular incident waves. Two different types of OWC devices: (i) LIMPET device (sloping-face OWC device) and (ii) quarter-circle-shaped front wall OWC device are considered for the present study. Detailed derivations of the parameters associated with the performance of the OWC devices under the action of irregular waves are provided. To analyze the efficiency of the OWC devices in real sea conditions, the Bretschneider Spectrum is taken as the incident wave spectrum along with nine sea states represent the local wave climate at the OWC plant site Pico, Portugal. The annual-averaged plant efficiencies of the two aforementioned OWC devices are analyzed as a function of chamber length, submergence depth, turbine rotor diameter, and rotational speed of the Wells turbine. It is observed that the annual-averaged plant efficiency can be enhanced significantly with appropriate combinations of chamber length, submergence depth, and turbine characteristics.

Estimating the heat transfer in deep underground geothermal systems is a challenging task. The concept of explicitly describing the heat transfer between phases has been shown superior to the conventional approach but the heat transfer coefficient of fractures is still ambiguous. In this work, a definition of the lower and upper bound of the heat transfer coefficient between rock and flowing fluid in a single rock fracture is derived and validated with almost 250 experiments from other studies. The resulting values range between 8 and 260 W/m2 °C, with upper bounds roughly a factor 10 larger. Further, as shown in this work, the assumption of local thermal equilibrium can result in lower production temperatures than the assumption of heat transfer between phases depending on reservoir conditions. A dimensionless number is derived to distinct those cases and to determine the lower limit of the outflow temperature in any scenario. The results of this work enable a quantification of the value range of the heat transfer coefficient from laboratory experiments and allow a tabulation of the heat transfer coefficient for all kind of scenarios. The presented results can be used in discrete fracture models for an improved prognosis of production temperatures.