Ephemeral State Research Articles

The ephemeral state of ice in micro cold traps on the Moon

Micro cold traps stand out as promising targets for future investigation missions to the lunar polar regions, due to their greater accessibility compared to macro cold traps. However, this advantage naturally comes at the cost of their size, which limits the amount of ice they can potentially harbor. Here, we investigate the permanently shadowed volume (PSV) of micro cold traps — an upper limit for their potential ice capacity. We find that, as expected, the PSV depth increases with latitude and surface roughness, but is on average much shallower (∼0.5−1%) compared to the topographic baseline. By comparing the expected destruction and accumulation rates of ice to the potential maximum capacity of micro cold traps, we predict their infill as a function of lateral size, and the lifetime of the ice they harbor. Our results could be used by future investigation missions to the lunar polar regions to constrain the delivery rate and delivery mechanism of ice to the Moon.

Endangered giant kelp forests support similar fish and macroinvertebrate communities to sympatric stipitate kelp forests

Kelp forests provide habitat for many species, but it remains uncertain whether specific kelp forest types support distinct biodiversity. Surface canopy-forming giant kelp (Macrocystis pyrifera) forests in Tasmania, Australia, have declined significantly due to climate change, and have been widely replaced by forests dominated by smaller stipitate kelps like Ecklonia radiata. However, there is limited knowledge of the community composition of Macrocystis forests and how this may differ from the stipitate kelp forest community. Underwater visual census surveys were conducted of the fishes and macroinvertebrates (> 2.5 cm length) in remnant Macrocystis forests in south-eastern Tasmania, and in adjacent stipitate kelp forests. 18 sites (9 of each forest type) were surveyed across two regions during the period of peak growth and canopy cover (i.e. winter-spring). Faunal community composition varied little between forest types, although Macrocystis forests supported more than double the abundance and biomass of mobile fishes, while cryptic fishes differed by forest type depending on region. Macroinvertebrate assemblages did not differ between forest types nor regions. Thus, for the taxa and time period examined, Tasmanian Macrocystis and stipitate kelp forests supported mostly similar faunal communities. Kelp forest communities showed spatial variation and were also likely influenced by a variety of other habitat characteristics, such as the relatively small patch sizes and/or ephemeral state of the remnant Macrocystis forests. Quantifying the community structure of these endangered communities informs the ecological changes that have occurred and will serve as an important reference for ongoing conservation and restoration activities.

The state of transience, and its influence on the wish to die of advanced disease patients: insights from a qualitative phenomenological study

BackgroundThe experience of Wish to Die is common in patients living with Advanced Disease. It has been studied worldwide and qualitative studies have contributed to the understanding of the complexity of the phenomenon of the WTD but a deeper understanding on the individual’s views is still needed. The objective of this study was to identify common characteristics of the experience of wish to die in advanced disease.MethodsA phenomenological study was carried out with multicenter participation of patients with advanced disease who had expressed their wish to die to health professionals. Semi-structured interviews were employed to obtain an in-depth perspective of each patient’s lived experience. A phenomenological analysis of the data collected was performed to describe and explore the characteristic aspects of the phenomenon under study.ResultsFourteen patients with advanced disease were interviewed. Most of them had cancer. In the analysis of the patients’ accounts of their experiences, three common characteristics were identified: a) experiencing a state of transience; b) the attempt to reconnect with oneself; and c) additional disease-related aspects that influence the wish to die. Patients expressed the need for a safe space to address the wish to die and the importance of receiving care that considers both ‘being’ and ‘doing’.ConclusionsPatients with advanced disease and wish to die experience a state of transience where the patient lives and ephemeral state of existence. Interventions focused on reinforcing the intrinsic value of the individual emerge as essential components of a compassionate accompaniment of those facing the wish to die.

An Ephemeral State on the Enduring Steppe

Abstract Baroun Tala, or the Khoshoud Khanate, was the first of three khanates created by the Oirat Mongols of the seventeenth century (1642), followed by the Jöüngar (1678) and Kalmyk Khanates (1681). It rose at a time when the two most powerful noble Oirat lineages, the Choros and Khoshoud, were close allies. The Khoshoud ruled in Kükünour and Tibet from 1642 to 1720, some 78 years. That history is summarised herein. The Khoshoud alliance with the Jöüngars (ruled by the Choros) ended in 1676 when Choros Galdan Boshugtu defeated the Khoshoud Chechen Khan and scattered his people. The Khoshoud Khanate was tied to the Fifth Dalai Lama and the centralisation of governance that occurred under his newly established political authority. The end of the Khoshoud Khanate is linked to the demise of the Sixth Dalai Lama, their failed alliance with the Jöüngars and ultimate capitulation to the Qing.

HACM: High Availability Control Method in Container-Based Microservice Applications Over Multiple Clusters

Emerging cloud-native technologies, such as container runtime and container orchestrator, offer unprecedented agility in developing and running applications, especially when combined with microservice-style architecture. Several commercial Samsung Network products such as Samsung Element Management System (S-EMS), 5G Radio Access Network (RAN) & Core network elements are being redesigned to fit the microservice paradigm. The cloud environment allows enterprises to scale their applications on-demand with minimum cost; however, it is often difficult to use containers without sacrificing the many benefits offered by container technology. S-EMS manages 5G RAN & Core network elements (NEs) deployed nationwide, and systematically stores a huge volume of stateful data per second. Containers are characterized to have an ephemeral state, hence ‘stateful-ness’ aspect of S-EMS makes management more complex. The existing system in a container-based application does not support geo-redundancy where services/data are stateful/state dependent. In this paper, different challenges around geo-redundancy between different independent Kubernetes set up with active and standby modes between the sites where state-dependent data is stored in each site are described. To overcome these challenges, we propose the High Availability Control Method (HACM) - which enables the Kubernetes cluster to be active and standby, where state-dependent data and context-based operations are intrinsically supported by the underlying S-EMS container application. Our approach has been designed to maintain the geo-redundancy philosophy of cloud-native by associating the status of each site using high availability (HA), switching over services based on the health of applications, deciding state when there are conflicts in site state, and the option to auto fallback based on user preference and services are transferred between sites without user intervention with optimized storage that ensures consistency, persistence, reliability, and availability. Through evaluation, we show that HACM with S-EMS can facilitate geo-redundancy HA, while not posing a significant burden on the Cloud.

On the features of evolutionary process in plants: diploidization of the genomes and karyotypes

As estimated by karyosystematists, from 30 to 50 % of land plant species exhibit polyploid karyotypes, respectively, from 50 to 70 % of plants are diploids. One of the mechanisms of diploidization of a neopolyploid karyotype is chromosomal rearrangements leading to a change in the chromosome number in genomes - so-called dysploidy. In parallel with the processes of karyotype diploidization, contributing to it and supplementing it, there are processes of structural and epigenetic diploidization of the genome, the loss of part of the duplicated genes. It may be that the role of genome polyploidy in plant evolution lies primarily in the fact that this ephemeral state is primarily an effective way to destabilize the genome, a source of many new combinations of alleles that pass through a rigid selection sieve and are realized later at the secondary diploid stage. The transition from a polyploid to a diploid state is justified by the fact that neopolyploids cannot provide a high percentage of gametes carring balanced chromosome sets due to problems with chromosome pairing in meiosis I. The mechanisms of transition to strict pairwise chromosome pairing are such that automatically leads to diploidization of both the genome and the karyotype. It is also important that the diploid karyotype provides more stringent, faster, more efficient selection of adaptively important new combinations of alleles, thereby contributing to the accumulation of taxonomically significant traits, speciation, and, as a result, to progressive evolution.

La festa della Porchetta a Bologna: nuove prospettive di indagine (ii)

The essay reconstructs some episodes of the Feast of the Porchetta. A civic event of long history that, at least from the end of the Sixteenth Century, used different artistic, literary, musical and spectacular typologies to convey the ambitions of the Senatorial aristocracy of Felsina. It was also a highlight of the ephemeral state and allowed Bologna to be assigned its rightful place among the European capitals of the spectacle of the Ancient Regime. An extensive unpublished documentation preserved at the Archivio di Stato di Bologna, including two contracts for the construction of theatres and workshops for the fairs of 1627 and 1702, and an icnography of 1697, testify to an unexpected organizational punctuality.

Dissipative phenomena in QCD plasma state created in heavy ion collisions

Modern heavy ion experiments reach collision energies that span the QCD phase diagram in the region of a partonic plasma state called the quark-gluon plasma (QGP). This relativistic QCD plasma is a strongly coupled hot/dense medium that lasts only a few fm/c. Being such a ephemeral state of matter, the only effective information about it is contained in the final particle shower collected by the experiment. Plethora of measurements show that the QGP behaves like a relativistic liquid with very small dissipative effects. Phenomenologically, a full theoretical framework of the QGP comprises of initial medium conditions, viscous hydrodynamics and particle shower (hadronization) phase. Each of these phases determines the predictive power of the model and puts a direct quantitative constrain on dissipative contributions when compared to data.

Violence, Insecurity and Marginality in Pastoralist Spaces: The Horn of Africa and the Sahel Regions

The pastoral world is defined by the prevalence of war, various forms of insecurity and lack of development, which constitutes violence in all its forms: direct war violence, structural violence (emanating from economic alienation and marginalisation, political repression, poverty, destitution and climatic vulnerability) and cultural violence (bias towards and the securitisation of pastoralist economic and social system). In effect, in human security parlance, the violation of freedom from fear and freedom from want is prevalent that it appears inherent to the nature of the pastoral way of being. The pastoral way of life is considered as an ephemeral state of encroachment of modern nation-state institutions. Therefore, pastoralist-state relations have always been strained. Their precarious existence on the fringe of every state they form part of is consequently considered as normalcy for pastoralists until their livelihood, socio-economic and political system is transformed into the dominant socio-economic and political systems the states are built on. The pastorialist conception of their livelihood and the entirety of their view of 'good life' is denigrated and their voice silenced. By reflecting on the book entitledS in the Horn of Africa and the Sahel by the United Nations Economic Commission for Africa, this review article examines violence in pastoral society.

Data stream event prediction based on timing knowledge and state transitions

We study a practical problem of predicting the upcoming events in data streams using a novel approach. Treating event time orders as relationship types between event entities, we build a dynamic knowledge graph and use it to predict future event timing. A unique aspect of this knowledge graph embedding approach for prediction is that we enhance conventional knowledge graphs with the notion of "states"---in what we call the ephemeral state nodes---to characterize the state of a data stream over time. We devise a complete set of methods for learning relevant events, for building the event-order graph stream from the original data stream, for embedding and prediction, and for theoretically bounding the complexity. We evaluate our approach with four real world stream datasets and find that our method results in high precision and recall values for event timing prediction, ranging between 0.7 and nearly 1, significantly outperforming baseline approaches. Moreover, due to our choice of efficient translation-based embedding, the overall throughput that the stream system can handle, including continuous graph building, training, and event predictions, is over one thousand to sixty thousand tuples per second even on a personal computer---which is especially important in resource constrained environments, including edge computing.

A New Route for Dioxygen Activation Uncovered from Quantum Mechanics Investigations of X‐Ray‐Diffraction‐Captured Intermediates of the Ferroxidase Reaction of Ferritins from Gram‐Negative Bacteria

AbstractFollowing the recent reassessment from X‐ray‐diffraction‐caught short‐path uptake to wide permeation of the S20A mutant Escherichia coli ferritin by ferrous ions, what happens when dioxygen gets to the diiron system is investigated. It is shown that the previously X‐ray‐caught situation of an unbound‐dioxygen diferrous state actually is an ephemeral state that changes into a P‐type peroxodiferric state, while a water molecule moves to bridge the two ferric ions, in what appears to be a remarkable redox process. All this stems from density functional theory (DFT)‐based quantum mechanics‐molecular mechanics and broken symmetry (BS) calculations that are extended to X‐ray‐diffraction‐caught oxodiferric and I‐type peroxodiferric systems from other subunits of the same crystal structure, validating them while determining antiferromagnetic coupling with all such diiron systems except the oxodiferric one. The latter converged, on BS, to ferromagnetic coupling under a wide variety of hybrid DFT functionals and basis sets. The trend of the Heisenberg J coupling reflects and substantiates the structures of the diiron core.

A new strong security model for stateful authenticated group key exchange

Stateful authenticated group key exchange (stAGKE) represents an important class of authenticated group key exchange (AGKE) such as tree-based AGKE. The computation of either ephemeral public key or session key in a new stAGKE session may be based on the ephemeral secret state from some previously established session. We notice that earlier AGKE models may be not able to provide appropriate security arguments for stAGKE. In this work, a new model is proposed for stAGKE to formulate security properties in particular for resistance to the leakage attacks on ephemeral key. To be of independent interest, the new model is also flexible, which can be used for analyzing either stateless or stateful AGKE protocols. We show the validity of our model by introducing a new tree-based protocol construction for stAGKE. The proposed scheme is proven secure in our new proposed model without random oracles.

The Promise of Performance in the Arab World

PAJ 106 (2014), pp. 113–118.  113 doi:10.1162/PAJJ _a_00183 Theatre entails the physical practice and site of performance, and as such exists in an ephemeral state with unique methodologies to document and present this research. Contemporary efforts — evident in both The Theatres of Morocco, Algeria and Tunisia and Doomed by Hope — peel back layers of live art from their historical, political, and cultural contexts to resituate this medium squarely within our present day.

Coherent state transfer between itinerant microwave fields and a mechanical oscillator

Macroscopic mechanical oscillators have been coaxed into a regime of quantum behaviour by direct refrigeration or a combination of refrigeration and laser-like cooling. This result supports the idea that mechanical oscillators may perform useful functions in the processing of quantum information with superconducting circuits, either by serving as a quantum memory for the ephemeral state of a microwave field or by providing a quantum interface between otherwise incompatible systems. As yet, the transfer of an itinerant state or a propagating mode of a microwave field to and from a storage medium has not been demonstrated, owing to the inability to turn on and off the interaction between the microwave field and the medium sufficiently quickly. Here we demonstrate that the state of an itinerant microwave field can be coherently transferred into, stored in and retrieved from a mechanical oscillator with amplitudes at the single-quantum level. Crucially, the time to capture and to retrieve the microwave state is shorter than the quantum state lifetime of the mechanical oscillator. In this quantum regime, the mechanical oscillator can both store quantum information and enable its transfer between otherwise incompatible systems.

In your dreams

A visit to the land of nod takes your mind on fabulous adventures. What shapes them, asks David Robson

Blurred Architecture: Duration and performance in the work of Diller Scofidio + Renfro

Architects Elizabeth Diller and Ricardo Scofidio have questioned conventional approaches to spatial temporality and the situation of architecture since the late 1970s. Now joined by Charles Renfro, the installation and architectural projects of their interdisciplinary design studio Diller Scofidio + Renfro are representative of the shift from the aesthetic architectures of post-modernism towards a critical architecture based upon the principles of time-based art. As a reflection on the question of duration and performance, this article returns to Diller Scofidio + Renfro's temporary structure for the Swiss Expo in 2002. Blur Building, or Blur, underlines the occurrence of time through its continuously shifting structure and ephemeral state. Located on a steel-viewing platform on Lake Neuchâtel, Blur was a literal performance of its lakeside site as a series of water jets formed a suspended mist cloud around its steel frame: an ephemeral architecture of water and action. This event-based spatial ecology of Blur is typical of Diller Scofidio + Renfro's focus on the affect of architecture and the social consequence of buildings. Influenced by their initial explorations within a theatrical setting, Diller Scofidio + Renfro integrate the experience of technology and architecture to evoke the social and material contexts of the ‘site’ or situation. Notions of spectatorship and participation recur throughout their architectural interventions, as they aim to position architecture as a means of spatial and haptic revelation: where the event of architectural experience has a direct impact upon our embodied perception of ourselves. Framed by Dorita Hannah's notion of ‘spatial performativity’ and the writings of architect's such as Juhani Pallasmaa and Bernard Tschumi, this article concludes with by reflecting on how Blur is representative of the critical discourses that have shaped contemporary approaches to site and performance, the dramaturgy of architecture.

Taking Account of Time in Marketing Construct Validation: Theoretical and Methodological Problems

In marketing research, the definitions of constructs often involve a temporal dimension, which make them either an ephemeral state or a lasting trait or a combination of the two. However, researchers do not always confirm the temporal hypothesis used. There are various ways of going about such verification, but their implementation is sometimes tricky. The purpose of this paper is to clarify these techniques and their use. A model decomposing the variance of a constuct into stable, scalable and situational temporal components is put foward. This model is then used in two different case studies, one to test the temporal validity of a marketing construct viewed as a trait, the other to test the temporal validity of a marketing construct viewed as a state.

A practical bytecode interpreter for programmable routers on IXP network processors

WASP is a programmable router platform that allows end-hosts to store ephemeral state in routers along the path of IP flows and to execute packet-attached bytecode that processes this data. We exploit lessons from past active network research and our knowledge of network processors to design a minimal interpreter that favours language restrictions over run-time checks. WASP provides safety with limited performance penalty through predictable execution time and bounded usage of memory and network resources. WASP is expressive enough to enable several applications including statistics collection and service discovery. It can also detect common trunk of two Internet paths and exchange local measurements about these paths. We propose a robust implementation on the IXP2400 network processor, and evaluate its performance through short benchmark programs against native functions hard-coded in the router. We achieve latencies below [email protected], i.e. less than the reference IPv4 forwarding latency, and throughputs approaching 800kpps per core, which competes with, and sometimes even outperforms, native programs. We further exploit our results to give hints on further improving resource usage and guidelines on management of ephemeral stores in high-speed networks.

Scalable Network Management Using Lightweight Programmable Network Services

Although the Simple Network Management Protocol (SNMP) has proven to be a powerful tool for network administrators, it is widely accepted that SNMP does not offer the scalability or the functionality needed to manage large systems of routers and end systems. Active/programmable networks and mobile agent systems have been proposed as alternative network management solutions, offering new functionality and better scalability. Unfortunately, the flexibility and programmability of these (heavyweight) systems comes with its own set of problems, which has prevented them from becoming widely adopted. This paper presents an ultra-lightweight programmable network service called ephemeral state processing (ESP) that can be used to efficiently monitor and collect information from large-scale networks. Although the service offers a limited set of features, the building blocks it does offer can be combined in novel ways to solve a wide range of network management problems while avoiding the problems that plague (heavyweight) active network approaches. The simplicity of ESP allows us to make it available as a general-purpose service that can be used by all packets in the network. We demonstrate the utility of the service by showing how it can be used to efficiently solve common network management problems.

Lightweight network support for scalable end-to-end services

Some end-to-end network services benefit greatly from network support in terms of utility and scalability. However, when such support is provided through service-specific mechanisms, the proliferation of one-off solutions tend to decrease the robustness of the network over time. Programmable routers, on the other hand, offer generic support for a variety of end-to-end services, but face a different set of challenges with respect to performance, scalability, security, and robustness. Ideally, router-based support for end-to-end services should exhibit the kind of generality, simplicity, scalability, and performance that made the Internet Protocol (IP) so successful. In this paper we present a router-based building block called ephemeral state processing (ESP), which is designed to have IP-like characteristics. ESP allows packets to create and manipulate small amounts of temporary state at routers via short, predefined computations. We discuss the issues involved in the design of such a service and describe three broad classes of problems for which ESP enables robust solutions. We also present performance measurements from a network-processor-based implementation.