bluuebunny/crossref_metadata_2025_split huggingface dataset:
The potential for detecting ‘life as we don't know it’ by fractal complexity analysis
Authors: Azua-Bustos Armando , Vega-Martínez Cristian 
Published: June 2013

AbstractFinding life in the Universe entirely different to the one evolved on Earth is probable. This is a significant constraint for life-detecting instruments that were sent and may be sent elsewhere in the solar system, as how could we detect life as ‘we don't know it’? How could we detect something when we have no prior knowledge of its composition or how it looks like? Here we argue that disregarding the type of lifeform that could be envisioned, all must share in common the attribute of being entities that decrease their internal entropy at the expense of free energy obtained from its surroundings. As entropy quantifies the degree of disorder in a system, any envisioned lifeform must have a higher degree of order than its supporting environment. Here, we show that by using fractal mathematics analysis alone, one can readily quantify the degree of entropy difference (and thus, their structural complexity) of living processes (lichen growths and plant growing patterns in this case) as distinct entities separate from its similar abiotic surroundings. This approach may allow possible detection of unknown forms of life based on nothing more than entropy differentials of complementary datasets. Future explorations in the solar system, like Mars or Titan, may incorporate this concept in their mission planning in order to detect potential endemic lifeforms.
Perchlorate on Mars: a chemical hazard and a resource for humans
Authors: Davila Alfonso F. , Willson David , Coates John D. , McKay Christopher P. 
Published: June 2013

AbstractPerchlorate (ClO4−) is widespread in Martian soils at concentrations between 0.5 and 1%. At such concentrations, perchlorate could be an important source of oxygen, but it could also become a critical chemical hazard to astronauts. In this paper, we review the dual implications of ClO4−on Mars, and propose a biochemical approach for removal of perchlorate from Martian soil that would be energetically cheap, environmentally friendly and could be used to obtain oxygen both for human consumption and to fuel surface operations.
Comparative cross-linking and mass spectrometry of an intact F-type ATPase suggest a role for phosphorylation
Authors: Schmidt Carla , Zhou Min , Marriott Hazel , Morgner Nina , Politis Argyris , Robinson Carol V. 
Published: June 2013

AbstractF-type ATPases are highly conserved enzymes used primarily for the synthesis of ATP. Here we apply mass spectrometry to the F1FO-ATPase, isolated from spinach chloroplasts, and uncover multiple modifications in soluble and membrane subunits. Mass spectra of the intact ATPase define a stable lipid ‘plug’ in the FO complex and reveal the stoichiometry of nucleotide binding in the F1 head. Comparing complexes formed in solution from an untreated ATPase with one incubated with a phosphatase reveals that the dephosphorylated enzyme has reduced nucleotide occupancy and decreased stability. By contrasting chemical cross-linking of untreated and dephosphorylated forms we show that cross-links are retained between the head and base, but are significantly reduced in the head, stators and stalk. Conformational changes at the catalytic interface, evidenced by changes in cross-linking, provide a rationale for reduced nucleotide occupancy and highlight a role for phosphorylation in regulating nucleotide binding and stability of the chloroplast ATPase.
CD25 and CD69 induction by α4β1 outside-in signalling requires TCR early signalling complex proteins
Authors: Cimo Ann-Marie , Ahmed Zamal , McIntyre Bradley W. , Lewis Dorothy E. , Ladbury John E. 
Published: June 2013

Distinct signalling pathways producing diverse cellular outcomes can utilize similar subsets of proteins. For example, proteins from the TCR (T-cell receptor) ESC (early signalling complex) are also involved in interferon-α receptor signalling. Defining the mechanism for how these proteins function within a given pathway is important in understanding the integration and communication of signalling networks with one another. We investigated the contributions of the TCR ESC proteins Lck (lymphocyte-specific kinase), ZAP-70 (ζ-chain-associated protein of 70 kDa), Vav1, SLP-76 [SH2 (Src homology 2)-domain-containing leukocyte protein of 76 kDa] and LAT (linker for activation of T-cells) to integrin outside-in signalling in human T-cells. Lck, ZAP-70, SLP-76, Vav1 and LAT were activated by α4β1 outside-in signalling, but in a manner different from TCR signalling. TCR stimulation recruits ESC proteins to activate the mitogen-activated protein kinase ERK (extracellular-signal-regulated kinase). α4β1 outside-in-mediated ERK activation did not require TCR ESC proteins. However, α4β1 outside-in signalling induced CD25 and co-stimulated CD69 and this was dependent on TCR ESC proteins. TCR and α4β1 outside-in signalling are integrated through the common use of TCR ESC proteins; however, these proteins display functionally distinct roles in these pathways. These novel insights into the cross-talk between integrin outside-in and TCR signalling pathways are highly relevant to the development of therapeutic strategies to overcome disease associated with T-cell deregulation.
The surprising metastability of TeH2+
Authors: de Oliveira-Filho Antonio G. S. , Ornellas Fernando R. 
Published: June 2013

A high-level ab initio investigation of a manifold of electronic states of the diatomic dication TeH2+ is presented. Potential energy curves for both Λ + S and relativistic (Ω) states are constructed not only making evident the metastability of this system, but also the large energy splitting due to spin-orbit interactions. This effect is also very significant in the region close to the crossing of the 2Π and 4Σ− states, where avoided crossings between the Ω states have a relatively large impact on the height of the energy barriers. In contrast to TeH, with only two bound states (X1 2Π3/2 and X2 2Π1/2) below about 25 000 cm−1, in the case of TeH2+ a much richer energy profile is obtained indicating various possibilities of electronic transitions. Guided by the results of this study, the experimental characterization of these states is now a challenge to spectroscopists. Since close to the equilibrium region the double positive charge is centered on the tellurium atom, the binding in this system can be rationalized as a simple covalent bond between the pz and s orbitals of Te2+ and H, respectively. As the internuclear distance increases, the electron affinity of Te2+ overcomes that of H+ and the system dissociates into two singly charged fragments. A simulation of the double ionization spectra complements the characterization of the electronic states, and results of a mass spectrometric investigation corroborates the predicted transient existence of this metastable species.
Polyester synthesis genes associated with stress resistance are involved in an insect–bacterium symbiosis
Authors: Kim Jiyeun Kate , Won Yeo Jin , Nikoh Naruo , Nakayama Hiroshi , Han Sang Heum , Kikuchi Yoshitomo , Rhee Young Ha , Park Ha Young , Kwon Jeong Yun , Kurokawa Kenji , Dohmae Naoshi , Fukatsu Takema , Lee Bok Luel 
Published: June 2013

Significance
This study reports a previously unrecognized involvement of polyhydroxyalkanoate (PHA), known as a bacterial endocellular storage polymer, in an insect–bacterium symbiosis. Many bacteria in the environment accumulate PHA granules within their cells, which provide resistance to nutritional depletion and other environmental stresses. Here we demonstrate that synthesis and accumulation of PHA in the symbiont cells are required for normal symbiotic association with, and, consequently, positive fitness effects for the host insect. The requirement of PHA for symbiosis suggests that, contrary to the general expectation, the within-host environment may be, at least in some aspects, stressful for the symbiotic bacteria.
Saturnian mean motion resonances in meteoroid streams
Authors: Sekhar A. , Asher D. J. 
Published: June 2013

Abstract
Many previous works have shown the relevance and dynamics of Jovian mean motion resonances (MMR) in various meteoroid streams. These resonant swarms are known to have produced spectacular meteor displays in the past. In this work, we investigate whether any MMR due to Saturn are feasible, and subsequently check whether such effects are strong enough to trap meteoroids so as to cause enhanced meteor phenomena on Earth. Extensive numerical simulations are done on two major meteoroid streams, which are known to exhibit exterior Jovian resonances. The roles of the 1:6 and 5:14 Jovian MMR have already been studied in the Orionids and Leonids, respectively. Now we find strong evidence of 1:3 and 8:9 Saturnian MMR in Orionids and Leonids, respectively. The presence of compact dust trails in real space due to these two Saturnian resonances is confirmed from our calculations.
An observation of solar active region expansion into the heliosphere
Authors: Morgan H. 
Published: June 2013

Abstract
According to current models, solar closed-field active regions are isolated from contributing directly to the solar wind except through small- or large-scale magnetic reconnection, including coronal mass ejections. Here we show the first direct evidence of active regions contributing directly to the solar wind by a steady-state, quiescent expansion. Advanced image processing of coronagraph data reveals a large system of nested closed-field magnetic structures expanding and accelerating to heights of at least 14 R⊙ within a helmet streamer above a large active region. The system persists for several days, and must therefore be an important contribution to the slow solar wind.
Athenian Agora
Authors: Camp John 
Published: June 2013

A large open square, surrounded on all four sides by public buildings, the Agora of Athens was in all respects the center of town. From the beginning the square was used for a variety of activities: marketplace, elections, dramatic performances, athletic contests, religious processions, and military drill. The excavation of buildings, monuments, and small objects has illustrated the important role it played in all aspects of civic life. The senate chamber (bouleuterion), public office buildings (Royal Stoa, South Stoa I), and archives (metroon) have all been excavated. The law courts are represented by the discovery of bronze ballots and a water clock used to time speeches. The use of the area as a marketplace is suggested by the numerous shops and workrooms where potters, cobblers, bronzeworkers, and sculptors made and sold their wares. Long stoas, or colonnades, provided shaded walkways for those wishing to meet friends to discuss business, politics, or philosophy, and statues and commemorative monuments reminded citizens of former triumphs. A library and concert hall met cultural needs, and numerous shrines and temples received regular worship in the area. Thus administrative, political, judicial, commercial, social, cultural, and religious activities all found a place here together in the heart of ancient Athens from the 6th century bce until the 6th century ce.
Midrash and Aggadah
Authors: Visotzky Burton , Kamine Benjamin Haber 
Published: June 2013

Midrash (Hebrew: מדרש) is ancient rabbinic interpretation of scripture. Aggadah (Hebrew: אגדה) is rabbinic narrative. The two terms are, however, often used interchangeably to refer to those many aspects of rabbinic literature that are not related to Jewish behavior or law (Hebrew: הלכה). Rabbinic literature here refers to works composed by the rabbis in Late Antiquity, from approximately 70 ce (Common Era) up to 1000 ce (an arbitrary end point). From the time that Y. L. Zunz addressed the literature in 1832, academic study of Midrash and Aggadah has been ongoing. In the earliest years it was part of the great project of Wissenschaft des Judentums (Scientific study of Judaism), and it included historical-critical studies, philological inquiries, anthologies, translations, and critical editions of texts. More recently, scholars have compared midrashic and aggadic methods of interpretation and narration with those of religious and cultural groups contemporary with the rabbis: Hellenism and Roman paganism, patristic and Syriac Christianity, and early Islam. Throughout the study of Midrash and Aggadah, scholars have written on the theological significance of the field. Current scholarship focuses on literary interpretation of Midrash and Aggadah and the implications of their oral performance and on sensitivity to the discursive structures of rabbinic narrative, as well as the very methodologies used to study the field. Feminist and gender criticism, particularly focused on placing rabbinic narrative within the values and culture of the rabbis and their contemporaries, has also been applied to the study of these literatures, and the growth of such criticism has expanded scholarship to include work in disability studies and queer studies. The mid-20th century to date, in particular, has been a time of ferment and, since the 1970s, the study of Midrash and Aggadah has expanded broadly.
Moral Naturalism and Nonnaturalism
Authors: Crisp Roger 
Published: June 2013

Understood broadly, the debate between naturalists and nonnaturalists in ethics concerns the question of how morality, and in particular moral value, is related to the natural world. In contemporary philosophy, this is usually seen as primarily a metaphysical issue, though in the past the term “nonnaturalism” was sometimes applied to intuitionist positions in epistemology. Moral naturalists can be divided into two categories, realist and nonrealist. Realist naturalists believe that moral properties are a subset of natural properties, or are in some sense identical with or constituted by such properties. Nonrealist naturalists believe that although we can speak of moral properties, those properties are not themselves real in the way that natural properties are: their attribution may be the result of, say, our expressing certain attitudes we have, rather than our detecting certain properties “out there” in the world. This nonrealist view can still be described as a form of moral naturalism, since it seeks a naturalistic account of morality. However the metaphysical debate is understood, some account of what it is for a property to be natural will be required. This debate continues, but one position, influenced by G. E. Moore, identifies the natural properties in some way with those properties that feature in scientific explanations, or that are in some sense reducible to or constructible from such properties. That of course raises the question of what counts as a science. The term “naturalism” is also often used to refer to theories, usually neo-Aristotelian, according to which value is bound up with human nature.
Immanuel Kant: Ethics
Authors: Denis Lara 
Published: June 2013

The ethical theory of Immanuel Kant (b. 1724–d. 1804) exerted a powerful influence on the subsequent history of philosophy and continues to be a dominant approach to ethics, rivaling consequentialism and virtue ethics. Kant’s ethical thought continues to be studied in itself, as a part of his critical system of philosophy, in its historical context, and in relation to particular practical questions. Kant’s writings and lectures display the influence of the Stoics, Rousseau, Crusius, Wolff, Hutcheson, Hume, and others; Fichte, Hegel, Nietzsche, Bradley, Greene, Habermas, and Rawls are among the many philosophers whose moral philosophies can be read (in part) as responses to Kant. Salient foundational features of Kant’s ethics include: its a priori method, its conception of the will as autonomous, its categorical imperative, its theory of freedom, and its account of moral motivation. Kant maintained that foundational moral principles must be a priori, not based on observation or experience. Kant takes the moral law to be legislated by the will to itself. Unlike holy beings, human beings experience morality as a constraint upon our wills. For us, the moral law is a categorical imperative. All ethical duties are ultimately grounded in this supreme moral principle. If we are bound to obey the moral law, we must be capable of doing so; Kant holds that, even assuming causal determinism in the phenomenal world, morality reveals our (noumenal) freedom to us. Kant attributes moral worth only to action done from duty (i.e., from respect for the law), not from inclination. Significant aspects of Kant’s fully developed ethical theory include its rich theory of virtue and the virtues, its taxonomy of duties (which include duties to oneself as well as to others), its distinctive conceptions of the highest good and human evil, and its connections with Kant’s philosophies of history, religion, and human nature. Many of Kant’s own discussions of particular duties, virtues, and vices are controversial. For example, Kant appears to condemn all lies as violations of a duty to oneself. This entry focuses on Kant’s ethics rather than Kantian ethics more broadly. Despite that, it includes a number of pieces that apply, extend, or revise Kant’s ethics in some ways, as well as interpretations of Kant’s ethics that some commentators may object stray too far from Kant’s own stated views. Kant’s political philosophy is discussed only peripherally here, save for the section on the Doctrine of Right of the Metaphysics of Morals.
Economic History
Authors: Davis James 
Published: June 2013

The study of medieval economic history has a rich pedigree and has led to major, wide-ranging debates about the nature and causes of economic change. Many of the books and articles listed in this article consider the transformation of the medieval economy, often on a broad chronological canvas, from the end of the ancient world to the creation of notable feudal institutions and thence to the emergence of the Early Modern world and protocapitalist organizations. A number of renowned scholars from the early to mid-20th century left their mark on this subject, including Henri Pirenne (b. 1862–d. 1935), Marc Bloch (b. 1886–d. 1944), Michael Moissey Postan (b. 1898–d. 1981), and Georges Duby (b. 1919–d. 1996), and they greatly influenced succeeding generations of historians. In addition, the debates of medieval economic history have often been shaped by numerous theories and approaches founded in the disciplines of economics, sociology, anthropology, archaeology, and geography. However, the strength of the subject still resides in rigorous analysis of the archival evidence. Many scholars have trawled through this material to produce important detailed, empirical case studies, based on specific localities or regions; a number of these are highlighted in this bibliography and are frequently based on English manors, villages, and towns due to the wealth of documentation that survives for that country. Much work concentrates on agricultural structures, demographic trends, and commercial growth. Some events stand out as significant for structural economic change, not least the dramatic intervention of the Black Death in the mid-14th century, but also wars, famines, and the discovery of new international trade routes. However, most economic historians also recognize that their subject is about understanding the everyday lives and material circumstances of ordinary people and their households. Medieval economic history concerns not only the elite, seigneurial estates, long-distance trade, wealthy merchants, and financial institutions but also peasant agriculture, living standards, technology, local trade, urban economies, and social conflict. This bibliography mostly concentrates on medieval Europe, 400–1500, but in the last section suggestions for readings on a more global scale are given.
Louise Labé
Authors: Read Kirk D. 
Published: June 2013

Louise Labé (c. b. 1522–d. 1566) is the most well-known and celebrated woman writer of non-noble birth from the French Renaissance. While her published work (Œuvres, 1555) is modest in length, the variety of genres she employs (epistle, sonnet, elegy, prose dialogue), the robust evidence of her proto-feminist vocation, her strength of voice, and her mastery of Petrarchan and Neoplatonic conventions have made of her a hugely important figure in the literature of this period. Labé was born in the early 1520s to a family of wealthy rope makers in Lyon, a city at the crossroads of the burgeoning cultural Renaissance given its situation between Paris and Italy. Daughter of Pierre Charly and second wife Étiennette Roybet who died shortly after Labé’s birth, Louise received an uncommonly thorough humanist education, most probably in a convent setting (Le couvent de la Déserte), where it is conjectured she may have been sent by her very young stepmother. The volume that Labé published with one of the premier printing houses of her day (Jean de Tournes) offers a stunning trove of evidence in both prose and poetry of a female writer’s negotiation of the literary and social conventions that challenged learned women of this time. The Œuvres are prefaced by the epistolary dedication to the young Lyonnais noblewoman, Clémence de Bourges, a manifesto for women’s participation in letters wherein she implores the ladies of Lyon to look above their distaffs and join the writer’s enterprise. This call to writing is followed by a much lengthier but no less fiercely gendered Débat de Folie et d’Amour (Debate of folly and love), a mythological play that enacts many of the epistle’s issues in allegorical form. Following the debate are three elegies and a sonnet cycle of twenty-four poems, all manifesting a deep engagement with contemporary literary conventions as told in a consciously feminine voice: In her poetic work Labé inscribes on several occasions her regional sisterhood (ô Dames Lionnoises). Labé’s final sonnet (and final words in the Œuvres) serves as both an entreaty and an apology to the women she invites into her literary project. On the very next page begins the inscription of twenty-four homages to her by male contemporaries, an insurance policy of sorts, against the tide of scandal and criticism attached to her work and reputation. Their success continues to be the subject of some debate, as Louise Labé has endured centuries of both criticism and praise, shifting most dramatically in 2006 with the proposition that her works were not at all hers but cooked up by a clever male collaborative. Such is the legacy of a powerful woman writer at odds with 16th-century social and literary conventions and norms of gender.