Experiment: Metabolic shifts in the Antarctic fish Notothenia rossii in response to rising temperature and PCO2

Introduction Ongoing ocean warming and acidification increasingly affect marine ecosystems, in particular around the Antarctic Peninsula. Yet little is known about the capability of Antarctic notothenioid fish to cope with rising temperature in acidifying seawater. While the whole animal level is expected to be more sensitive towards hypercapnia and temperature, the basis of thermal tolerance is set at the cellular level, with a putative key role for mitochondria. This study therefore investigates the physiological responses of the Antarctic Notothenia rossii after long-term acclimation to increased temperatures (7°C) and elevated PCO2 (0.2 kPa CO2) at different levels of physiological organisation. Results For an integrated picture, we analysed the acclimation capacities of N. rossii by measuring routine metabolic rate (RMR), mitochondrial capacities (state III respiration) as well as intra- and extracellular acid-base status during acute thermal challenges and after long-term acclimation to changing temperature and hypercapnia. RMR was partially compensated during warm- acclimation (decreased below the rate observed after acute warming), while elevated PCO2 had no effect on cold or warm acclimated RMR. Mitochondrial state III respiration was unaffected by temperature acclimation but depressed in cold and warm hypercapnia-acclimated fish. In both cold- and warm-exposed N. rossii, hypercapnia acclimation resulted in a shift of extracellular pH (pHe) towards more alkaline values. A similar overcompensation was visible in muscle intracellular pH (pHi). pHi in liver displayed a slight acidosis after warm normo- or hypercapnia acclimation, nevertheless, long-term exposure to higher PCO2 was compensated for by intracellular bicarbonate accumulation. Conclusion The partial warm compensation in whole animal metabolic rate indicates beginning limitations in tissue oxygen supply after warm-acclimation of N. rossii. Compensatory mechanisms of the reduced mitochondrial capacities under chronic hypercapnia may include a new metabolic equilibrium to meet the elevated energy demand for acid-base regulation. New set points of acid-base regulation under hypercapnia, visible at the systemic and intracellular level, indicate that N. rossii can at least in part acclimate to ocean warming and acidification. It remains open whether the reduced capacities of mitochondrial energy metabolism are adaptive or would impair population fitness over longer timescales under chronically elevated temperature and PCO2.

Shifts of the psychometric function: distinguishing bias from perceptual effects.

Morgan, Dillenburger, Raphael, and Solomon have shown that observers can use different response strategies when unsure of their answer, and, thus, they can voluntarily shift the location of the psychometric function estimated with the method of single stimuli (MSS; sometimes also referred to as the single-interval, two-alternative method). They wondered whether MSS could distinguish response bias from a true perceptual effect that would also shift the location of the psychometric function. We demonstrate theoretically that the inability to distinguish response bias from perceptual effects is an inherent shortcoming of MSS, although a three-response format including also an "undecided" response option may solve the problem under restrictive assumptions whose validity cannot be tested with MSS data. We also show that a proper two-alternative forced-choice (2AFC) task with the three-response format is free of all these problems so that bias and perceptual effects can easily be separated out. The use of a three-response 2AFC format is essential to eliminate a confound (response bias) in studies of perceptual effects and, hence, to eliminate a threat to the internal validity of research in this area.

Paradigm shift in determining Neoproterozoic atmospheric oxygen

ACKNOWLEDGMENTS We thank the Geological Survey of Australia for permission to sample the Empress 1A and Lancer 1 cores, the Natural Sciences and Engineering Research Council of Canada for financial support (grant #7961–15) of U. Brand, and the National Natural Science Foundation of China for support of F. Meng and P. Ni (grants 41473039 and 4151101015). We thank M. Lozon (Brock University) for drafting and constructing the figures. We thank the editor, Brendan Murphy, as well as three reviewers (Steve Kesler, Erik Sperling, and an anonymous reviewer), for improving the manuscript into its final form ©The Authors Gold Open Access: This paper is published under the terms of the CC-BY license.

Super-Nernstian Shifts of Interfacial Proton-Coupled Electron Transfers: Origin and Effect of Noncovalent Interactions

Peer reviewed

Super-Nernstian Shifts of Interfacial Proton-Coupled Electron Transfers: Origin and Effect of Noncovalent Interactions

Peer reviewed

Még egyszer a "rendszerparadigmáról". Tisztázás és kiegészítések a posztszocialista régió tapasztalatainak fényében = About the system paradigm once again: Clarification and additions in the light of experiences in the post-socialist region

A paradigma kifejezést Thomas Kuhn honosította meg a tudományfilozófiában: így nevezte el azt a sajátos szemléletmódot, ahogyan egy kutatási irányzat rátekint vizsgálata tárgyára. Azonos paradigmát használó kutatók hasonló kérdésekre keresik a választ, hasonló módszereket és fogalmakat alkalmaznak. A szerző 1999-ben publikált cikkében vezette be a "rendszerparadigma" kifejezést, amely a társadalomban működő rendszereket helyezi a vizsgálat középpontjába. A tanulmány a posztszocialista átalakulás során szerzett tapasztalatok alapján fejleszti tovább a korábbi cikkben kifejtett elméleti gondolatokat. Az első rész a szocialista és a kapitalista rendszert hasonlítja össze; leírja fő jellemzőiket, majd megállapítja, hogy Észak-Korea és Kuba kivételével az egykori szocialista országokban meghonosodott a kapitalista rendszer. A második rész a politikai-kormányzati formák szerint tipologizálja a kapitalizmus változatait. Három markáns típust különböztet meg: a demokráciát, az autokráciát és a diktatúrát. Huntington a demokratizálás harmadik hullámáról írt. A tanulmány arra a következtetésre jut, hogy ez a hullám elapadt, a 47 posztszocialista ország lakosságának mindössze egytizede él demokráciában, a többiben autokrácia vagy diktatúra uralkodik. A harmadik rész Magyarországra alkalmazza a kialakított fogalmi és elemzési apparátust: itt kapitalizmus van, a politikai-kormányzati forma autokrácia - lényeges közös jellemzők mutathatók ki más kapitalista országokkal, illetve más autokráciákkal. Ez összefér azzal a felismeréssel, hogy egyes - nem alapvető jelentőségű - vonások egyediek, "hungarikumok", különböznek minden más ország tulajdonságaitól. _____ The expression paradigm, introduced into the philosophy of science by Thomas Kuhn for the way a research trend views the subject examined, denotes a case where researchers pursue similar questions by similar methods with similar concepts. The author introduced the expression system paradigm" in a 1999 article centred on the systems operating in society. This paper takes those theoretical ideas further, based on experience in the post-socialist transformation. The first part compares the socialist and capitalist systems and their main features, establishing that all former socialist countries but North Korea and Cuba have embraced the capitalist system. The second adds a typology of the varieties of capitalism by politico-governmental form, marking three types: democracy, autocracy and dictatorship. Huntington writes of a third wave of democratization, which this study concludes has ceased. Democracy reigns in only 10 per cent of the 47 post-socialist countries, autocracy or dictatorship in the others. The third part applies this conceptual and analytical framework to Hungary, where capitalism prevails, with autocracy as its politico-governmental form. It shows strongly similar features to other capitalist countries and other autocracies. This is compatible with recognizing that some features of less than fundamental importance are specific to Hungary and differ from those elsewhere.

The Irish paradigm on the natural progression of hepatitis C virus infection: an investigation in a homogeneous patient population infected with HCV 1b (Review)

The aetiological agent of chronic hepatitis C is the hepatitis C virus. The hepatitis C virus is spread by parenteral transmission of body fluids, primarily blood or blood products. In 1989, after more than a decade of research, HCV was isolated and characterised. The hepatitis C viral genome is a positive-sense, single-stranded RNA molecule approximately 9.4 kb in length, which encodes a polyprotein of about 3100 amino acids. There are 6 main genotypes of HCV, each further stratified by subtype. In 1994, a cohort of women was identified in Ireland as having been iatrogenically exposed to the hepatitis C virus. The women were all young and exposed as a consequence of the receipt of HCV 1b contaminated anti-D immunoglobulin. The source of the infection was identified as an acutely infected female. As part of a voluntary serological screening programme involving 62,667 people, 704 individuals were identified as seropositive for exposure to the hepatitis C virus; 55.4% were found to be positive for the viral genome 17 years after exposure. Of these women 98% had evidence of inflammation, but suprisingly, a remarkable 49% showed no evidence of fibrosis. Clinicopathology and virological analysis has identified associations between viral load and the histological activity index for inflammation, and, between inflammation and levels of the liver enzyme alanine aminotransferase. Infection at a younger age appears to protect individuals from progression to advanced liver disease. Molecular analyses of host immunogenetic elements shows that particular class II human leukocyte associated antigen alleles are associated with clearance of the hepatitis C virus. Additional class II alleles have been identified that are associated with stable viraemia over an extended period of patient follow-up. Although, investigation of large untreated homogeneous cohorts is likely to become more difficult, as the efficacy of anti-viral therapy improves, further investigation of host and viral factors that influence disease progression will help provide an evidence based approach were realistic expectations regarding patient prognosis can be ascertained.

Stimulus Integration and Parsing in the Primate Auditory Midbrain

Integrating information from multiple sources is a crucial function of the brain. Examples of such integration include multiple stimuli of different modalties, such as visual and auditory, multiple stimuli of the same modality, such as auditory and auditory, and integrating stimuli from the sensory organs (i.e. ears) with stimuli delivered from brain-machine interfaces.

The overall aim of this body of work is to empirically examine stimulus integration in these three domains to inform our broader understanding of how and when the brain combines information from multiple sources.

First, I examine visually-guided auditory, a problem with implications for the general problem in learning of how the brain determines what lesson to learn (and what lessons not to learn). For example, sound localization is a behavior that is partially learned with the aid of vision. This process requires correctly matching a visual location to that of a sound. This is an intrinsically circular problem when sound location is itself uncertain and the visual scene is rife with possible visual matches. Here, we develop a simple paradigm using visual guidance of sound localization to gain insight into how the brain confronts this type of circularity. We tested two competing hypotheses. 1: The brain guides sound location learning based on the synchrony or simultaneity of auditory-visual stimuli, potentially involving a Hebbian associative mechanism. 2: The brain uses a ‘guess and check’ heuristic in which visual feedback that is obtained after an eye movement to a sound alters future performance, perhaps by recruiting the brain’s reward-related circuitry. We assessed the effects of exposure to visual stimuli spatially mismatched from sounds on performance of an interleaved auditory-only saccade task. We found that when humans and monkeys were provided the visual stimulus asynchronously with the sound but as feedback to an auditory-guided saccade, they shifted their subsequent auditory-only performance toward the direction of the visual cue by 1.3-1.7 degrees, or 22-28% of the original 6 degree visual-auditory mismatch. In contrast when the visual stimulus was presented synchronously with the sound but extinguished too quickly to provide this feedback, there was little change in subsequent auditory-only performance. Our results suggest that the outcome of our own actions is vital to localizing sounds correctly. Contrary to previous expectations, visual calibration of auditory space does not appear to require visual-auditory associations based on synchrony/simultaneity.

My next line of research examines how electrical stimulation of the inferior colliculus influences perception of sounds in a nonhuman primate. The central nucleus of the inferior colliculus is the major ascending relay of auditory information before it reaches the forebrain, and thus an ideal target for understanding low-level information processing prior to the forebrain, as almost all auditory signals pass through the central nucleus of the inferior colliculus before reaching the forebrain. Thus, the inferior colliculus is the ideal structure to examine to understand the format of the inputs into the forebrain and, by extension, the processing of auditory scenes that occurs in the brainstem. Therefore, the inferior colliculus was an attractive target for understanding stimulus integration in the ascending auditory pathway.

Moreover, understanding the relationship between the auditory selectivity of neurons and their contribution to perception is critical to the design of effective auditory brain prosthetics. These prosthetics seek to mimic natural activity patterns to achieve desired perceptual outcomes. We measured the contribution of inferior colliculus (IC) sites to perception using combined recording and electrical stimulation. Monkeys performed a frequency-based discrimination task, reporting whether a probe sound was higher or lower in frequency than a reference sound. Stimulation pulses were paired with the probe sound on 50% of trials (0.5-80 µA, 100-300 Hz, n=172 IC locations in 3 rhesus monkeys). Electrical stimulation tended to bias the animals’ judgments in a fashion that was coarsely but significantly correlated with the best frequency of the stimulation site in comparison to the reference frequency employed in the task. Although there was considerable variability in the effects of stimulation (including impairments in performance and shifts in performance away from the direction predicted based on the site’s response properties), the results indicate that stimulation of the IC can evoke percepts correlated with the frequency tuning properties of the IC. Consistent with the implications of recent human studies, the main avenue for improvement for the auditory midbrain implant suggested by our findings is to increase the number and spatial extent of electrodes, to increase the size of the region that can be electrically activated and provide a greater range of evoked percepts.

My next line of research employs a frequency-tagging approach to examine the extent to which multiple sound sources are combined (or segregated) in the nonhuman primate inferior colliculus. In the single-sound case, most inferior colliculus neurons respond and entrain to sounds in a very broad region of space, and many are entirely spatially insensitive, so it is unknown how the neurons will respond to a situation with more than one sound. I use multiple AM stimuli of different frequencies, which the inferior colliculus represents using a spike timing code. This allows me to measure spike timing in the inferior colliculus to determine which sound source is responsible for neural activity in an auditory scene containing multiple sounds. Using this approach, I find that the same neurons that are tuned to broad regions of space in the single sound condition become dramatically more selective in the dual sound condition, preferentially entraining spikes to stimuli from a smaller region of space. I will examine the possibility that there may be a conceptual linkage between this finding and the finding of receptive field shifts in the visual system.

In chapter 5, I will comment on these findings more generally, compare them to existing theoretical models, and discuss what these results tell us about processing in the central nervous system in a multi-stimulus situation. My results suggest that the brain is flexible in its processing and can adapt its integration schema to fit the available cues and the demands of the task.

Perpetuating sales: enabling incumbent survival of radical technological shifts

This paper examines an industry whose incumbents’ specialised complimentary assets were their operations management and distribution channels. This advantage was seriously undermined by the advent of digital distribution. Radical technological change theories dictate that if incumbents in an industry without specialised complimentary assets will be replaced by entrants. This did not happen, and extant theories of incumbent survival do not explain why the incumbents remained dominant in the industry. We propose that survival is due to the unique industry characteristic of perpetuating sales. This paper will explain what is a perpetuating sales model and why does it enable incumbent survival?

Salutogenesis: a new paradigm for pervasive computing in healthcare environments?

Salutogenesis is now accepted as a part of the contemporary model of disease: an individual is not only affected by pathogenic factors in the environment, but those that promote well-being or salutogenesis. Given that "environment" extends to include the built environment, promotion of salutogenesis has become part of the architectural brief for contemporary healthcare facilities, drawing on an increasing evidence-base. Salutogenesis is inextricably linked with the notion of person-environment "fit". MyRoom is a proposal for an integrated architectural and pervasive computing model, which enhances psychosocial congruence by using real-time data indicative of the individual's physical status to enable the environment of his/her room (colour, light, temperature) to adapt on an on-going basis in response to bio-signals. This work is part of the PRTLI-IV funded programme NEMBES, investigating the use of embedded technologies in the built environment. Different care contexts require variations in the model, and iterative prototyping investigating use in different contexts will progressively lead to the development of a fully-integrated adaptive salutogenic single-room prototype.

Hispanic Orientalism: The Literary Development of a Cultural Paradigm, from Medieval Spain to Modern Latin America

This dissertation offers a novel approach to Hispanic Orientalism, developing a dynamic paradigm from its origins in medieval and Renaissance Iberia during the process of the Christian Reconquest, to its transatlantic migration and establishment in the early years of the Colony, from where it changed in late colonial and post-Independence Latin America, and onto modernity. The study argues that Hispanic Orientalism does not necessarily imply a negative depiction of the Other, a quality associated with the traditional critique of Saidian Orientalism. Neither, does it entirely comply with the positivist approach suggested in the theoretical research of Said’s opponents, like Julia Kushigian. This dissertation also argues that sociopolitical changes and the shift in the discourse of powers, from imperial to non-imperial, had a significant impact of the development of Hispanic Orientalism, shaping the relationship with the Other. The methodology involves close reading of representative texts depicting the interactions of the dominant and dominated societies from each of the four historic periods that coincided with significant sociopolitical transformations in Hispanic society. Through an intercultural approach to literary studies, social history, and religious studies, this project develops an original paradigm of Hispanic Orientalism, derived from the image of the reinvented Semitic Other portrayed in the literary works depicting the relationship between the hegemonic and the subaltern cultures during the Reconquest period in Spain. Then, it traces the turn of the original paradigm towards reinterpretation during its transatlantic migration to Latin America through the analysis of the chronicles and travelogs of the first colonizers and explorers. During the transitional late colonial and early Independence periods Latin America sees a significant change in the discourse of powers, and Hispanic Orientalism reflects this oscillation between the past and the present therough the works of the Latin American authors from the seventeenth to the nineteenth centuries. Finally, once the non-imperial discourse of power established itself in the former Colony, a new modern stage in the development of Hispanic Orientalist paradigm takes place. It is marked by the desire to differentiate itself from the O(o)thers, as manifested in the works of the representatives of Modernism and the Boom.

Potential Shifts in Canadian High Arctic Sedimentary Organic Matter Composition With Permafrost Active Layer Detachments

Increased temperature and precipitation in Arctic regions have led to deeper thawing and structural instability in permafrost soil. The resulting localized disturbances, referred to as active layer detachments (ALDs), may transport organic matter (OM) to more biogeochemically active zones. To examine this further, solid state cross polarization magic angle spinning 13C nuclear magnetic resonance (CPMAS NMR) and biomarker analysis were used to evaluate potential shifts in riverine sediment OM composition due to nearby ALDs within the Cape Bounty Arctic Watershed Observatory, Nunavut, Canada. In sedimentary OM near ALDs, NMR analysis revealed signals indicative of unaltered plant-derived material, likely derived from permafrost. Long chain acyclic aliphatic lipids, steroids, cutin, suberin and lignin occurred in the sediments, consistent with a dominance of plant-derived compounds, some of which may have originated from permafrost-derived OM released by ALDs. OM degradation proxies for sediments near ALDs revealed less alteration in acyclic aliphatic lipids, while constituents such as steroids, cutin, suberin and lignin were found at a relatively advanced stage of degradation. Phospholipid fatty acid analysis indicated that microbial activity was higher near ALDs than downstream but microbial substrate limitation was prevalent within disturbed regions. Our study suggests that, as these systems recover from disturbance, ALDs likely provide permafrost-derived OM to sedimentary environments. This source of OM, which is enriched in labile OM, may alter biogeochemical patterns and enhance microbial respiration within these ecosystems.

3D considerations for motion perception and visuomotor transformations

Moving through a stable, three-dimensional world is a hallmark of our motor and perceptual experience. This stability is constantly being challenged by movements of the eyes and head, inducing retinal blur and retino-spatial misalignments for which the brain must compensate. To do so, the brain must account for eye and head kinematics to transform two-dimensional retinal input into the reference frame necessary for movement or perception. The four studies in this thesis used both computational and psychophysical approaches to investigate several aspects of this reference frame transformation. In the first study, we examined the neural mechanism underlying the visuomotor transformation for smooth pursuit using a feedforward neural network model. After training, the model performed the general, three-dimensional transformation using gain modulation. This gave mechanistic significance to gain modulation observed in cortical pursuit areas while also providing several testable hypotheses for future electrophysiological work. In the second study, we asked how anticipatory pursuit, which is driven by memorized signals, accounts for eye and head geometry using a novel head-roll updating paradigm. We showed that the velocity memory driving anticipatory smooth pursuit relies on retinal signals, but is updated for the current head orientation. In the third study, we asked how forcing retinal motion to undergo a reference frame transformation influences perceptual decision making. We found that simply rolling one's head impairs perceptual decision making in a way captured by stochastic reference frame transformations. In the final study, we asked how torsional shifts of the retinal projection occurring with almost every eye movement influence orientation perception across saccades. We found a pre-saccadic, predictive remapping consistent with maintaining a purely retinal (but spatially inaccurate) orientation perception throughout the movement. Together these studies suggest that, despite their spatial inaccuracy, retinal signals play a surprisingly large role in our seamless visual experience. This work therefore represents a significant advance in our understanding of how the brain performs one of its most fundamental functions.

The role of paradigm analysis in the development of policies for a resource efficient economy

Policy makers are often called upon to navigate between scientists’ urgent calls for long-term concerted action to reduce the environmental impacts due to resource use, and the public’s concerns over policies that threaten lifestyles or jobs. Against these political challenges, resource efficiency policy making is often a changeable and even chaotic process, which has fallen short of the political ambitions set by democratically elected governments. This article examines the importance of paradigms in understanding how the public collectively responds to new policy proposals, such as those developed within the project DYNAmic policy MiXes for absolute decoupling of environmental impact of EU resource use from economic growth (DYNAMIX). The resulting proposed approach provides a framework to understand how different concerns and worldviews converge within public discourse, potentially resulting in paradigm change. Thus an alternative perspective on how resource efficiency policy can be development is proposed, which envisages early policies to lay the ground for future far-reaching policies, by altering the underlying paradigm context in which the public receive and respond to policy. The article concludes by arguing that paradigm change is more likely if the policy is conceived, framed, designed, analyzed, presented, and evaluated from the worldview or paradigm pathway that it seeks to create (i.e. the destination paradigm).

Fossil associations from the middle and upper Eocene strata of the Pamplona Basin and surrounding areas (Navarre, western Pyrenees)

Fossil associations from the middle and upper Eocene (Bartonian and Priabonian) sedimentary succession of the Pamplona Basin are described. This succession was accumulated in the western part of the South Pyrenean peripheral foreland basin and extends from deep-marine turbiditic (Ezkaba Sandstone Formation) to deltaic (Pamplona Marl, Ardanatz Sandstone and Ilundain Marl formations) and marginal marine deposits (Gendulain Formation). The micropalaeontological content is high. It is dominated by foraminifera, and common ostracods and other microfossils are also present. The fossil ichnoasssemblages include at least 23 ichnogenera and 28 ichnospecies indicative of Nereites, Cruziana, Glossifungites and ?Scoyenia-Mermia ichnofacies. Body macrofossils of 78 taxa corresponding to macroforaminifera, sponges, corals, bryozoans, brachiopods, annelids, molluscs, arthropods, echinoderms and vertebrates have been identified. Both the number of ichnotaxa and of species (e. g. bryozoans, molluscs and condrichthyans) may be considerably higher. Body fossil assemblages are comparable to those from the Eocene of the Nord Pyrenean area (Basque Coast), and also to those from the Eocene of the west-central and eastern part of South Pyrenean area (Aragon and Catalonia). At the European scale, the molluscs assemblages seem endemic from the Pyrenean area, although several Tethyan (Italy and Alps) and Northern elements (Paris basin and Normandy) have been recorded. Palaeontological data of studied sedimentary units fit well with the shallowing process that throughout the middle and late Eocene occurs in the area, according to the sedimentological and stratigraphical data.