bluuebunny/crossref_metadata_2025 huggingface dataset:
Basic Ethnography at the Barricades
Authors: Naguib Nefissa
Published: July 2011

We did not see them growing up. We did not think these jaded middle-class boys and girls would one day be resilient and hold their ground. We did not realize that they would be brave, supremely articulate, and driven by aspirations beyond our dreams. The whole thing started with the desperate act of self-immolation by a young Tunisian man. His death sparked a wave of rage against poverty, social exclusion, and corruption. Almost overnight, young men and women created spaces in squares, streets, and alleys where we could imagine new Arab countries. Enraged yet nonviolent, they used technology and the vocabulary of democracy to connect and mobilize ordinary Arab citizens of all walks of life and capture the attention of the world. In Egypt, Tahrir Square became the epicenter of the people's demands for bread, dignity, and social justice. Without leaders or a timetable, but with unconditional demands for immediate change, online activists provided us with physical and social grounds to imagine a new country. We all brought something to the square: blood, medicines, bandages, food, water, blankets, generators, diapers, mobile-phone chargers, garbage bags, wipes, and our own personal notes to the regime (and the world) written in bold letters. Mine just said: “Leave.”
Imagining “the Political” Otherwise
Authors: El Shakry Omnia
Published: July 2011

The recent revolutions and uprisings in the Middle East represent a rare historic opening for scholars, offering us nothing short of the opportunity to rethink the possibilities of history and our conceptions of “the political” itself. In so doing, we might be more open to the ways in which the empirical continually challenges us to rethink our conceptual models. Thus, while some immediately sought to categorize and co-opt the revolutions for their own purposes (Žižek's impassioned, albeit simplistic, “freedom is universal”), others listened closely to the voices on the ground in Tahrir and elsewhere. Now, if ever, is the time to critically reevaluate some of our theoretical models, our tenacious binaries (chiefly among them secularism versus Islamism) and our catch-all monolithic frameworks, such as “the military dictatorship,” “authoritarianism,” and even “neoliberalism.”
Arab Revolutions and the Study of Middle Eastern Societies
Authors: Bayat Asef
Published: July 2011

The speed, spread, and democratic thrust of Arab revolutionary uprisings conjure up the revolutionary waves of 1848 and 1989 in Europe. Spearheaded by educated youth, the Arab uprisings have been brought to fruition by the masses of ordinary people (men, women, Muslims, and non-Muslims) who have mobilized at an astonishing scale against authoritarian regimes in pursuit of social justice, democratic governance, and dignity. If this broad observation is valid, then these social earthquakes are likely to unsettle some of the most enduring perspectives on the region. To begin with, they should undermine “Middle East exceptionalism,” with its culturalist focus informed by assumptions of “stagnant culture,” “fatalist Muslims,” and “unchangeable polity.” In political science, students of “regime stability” and the “authoritarian resiliency” of Arab states may have to reevaluate their conceptual premises. The analytical relevance of the concept of “rentier state” as the political basis of authoritarian stability might likewise need serious reformulation. The blatant cash handouts by some Arab Gulf states to “buy opposition” during the wave of protests in February and March 2011 do not seem to have worked.
A Decline of Identity Politics
Authors: Louër Laurence
Published: July 2011

Religious actors and religious language are not absent from the Arab revolutions, but a striking feature of these movements is that they depart from Islamist identity politics, which tended to portray the problems of the Arab world as the result of Muslims’ betrayal of their religious identity. Slogans referencing Islam are remarkably few, even in contexts like Egypt where Islamist movements are an important organized political force. Similar to many Islamist activists, the youth who initiated these movements are exasperated by growing economic inequalities. Unlike the former, however, they do not feel the need to frame this issue in religious terms, but rather mobilize universal notions such as democracy, freedom, justice, and equality. This is the case even in societies with sharp religious divides such as Bahrain, where the overwhelmingly Shiʿi demonstrators oppose a Sunni-dominated regime. Regardless of whether the uprisings will succeed in achieving a genuine regime change, new political movements are likely to emerge that focus on political freedom and the reduction of social inequalities rather than projects maintaining Islam as a solution. The question remains whether this trend simply went unnoticed by the majority of the scholarly community working on the Middle East or whether it is something that emerged in the dynamics of the uprisings themselves. Either way, the phenomenon must now be analyzed. Does it mean a decline of the Islamist ideology? Will it permit an empowerment of existing liberal political movements? Of trade unionism? What does it reveal about the integration of the Middle East within global political trends?
TASTE AND CLASS IN LATE OTTOMAN BEIRUT
Authors: Abou-Hodeib Toufoul
Published: July 2011

This article deals with the material aspects of the late Ottoman home in Beirut, focusing on the notion of taste (dhawq) and its role in constructing class boundaries. It looks at how intellectuals used taste to articulate a prescriptive middle-class domesticity revolving around the woman as manager of the house and privileging moderation and authenticity in consumption habits. Rather than take such tastes as representative of actual consumption habits of an emerging middle class, and arguing for an approach that goes beyond taste as a construct, the article investigates the potentiality of new objects for subverting the existing social order. Based on a marital-conflict case brought to the Hanafi court, the article explores how one such object, a phonograph, opened interpretive possibilities in the gendered rigidity of court procedures.
Adjusting the parameters of the mechanical impedance for velocity, impact and force control
Authors: Stanisic Ranko Zotovic , Fernández Ángel Valera
Published: July 2011

This work is dedicated to the analysis of the application of active impedance control for the realisation of three objectives simultaneously: velocity regulation in free motion, impact attenuation and finally force tracking. At first, a brief analysis of active impedance control is made, deducing the value of each parameter in order to achieve the three objectives. It is demonstrated that the system may be made overdamped with the adequate selection of the parameters if the characteristics of the environment are known, avoiding high overshoots of force during the impact. The second and most important contribution of this work is an additional measure for impact control in the case when the characteristics of the environment are unknown. It consists in switching among different values of the parameters of the impedance in order to dissipate faster the energy of the system, limiting the peaks of force and avoiding losses of contact. The optimal switching criteria are deduced for every parameter in order to dissipate the energy of the system as fast as possible. The results are verified in simulation.
Dynamic modeling and stability optimization of a redundant mobile robot using a genetic algorithm
Authors: Mosadeghzad M. , Naderi D. , Ganjefar S.
Published: July 2011

Kinematic reconfigurable mobile robots have the ability to change their structure to increase stability and decrease the probability of tipping over on rough terrain. If stability increases without decreasing center of mass height, the robot can pass more easily through bushes and rocky terrain. In this paper, an improved sample return rover is presented. The vehicle has a redundant rolling degree of freedom. A genetic algorithm utilizes this redundancy to optimize stability. Parametric motion equations of the robot were derived by considering Iterative Kane and Lagrange's dynamic equations. In this research, an optimal reconfiguration strategy for an improved SRR mobile robot in terms of the Force–Angle stability measure was designed using a genetic algorithm. A path-tracking nonlinear controller, which maintains the robot's maximum stability, was designed and simulated in MATLAB. In the simulation, the vehicle and end-effector paths and the terrain are predefined and the vehicle has constant velocity. The controller was found to successfully keep the end-effector to the desired path and maintained optimal stability. The robot was simulated using ADAMS for optimization evaluation.
Science and Cinema
Authors: Wellmann Janina
Published: July 2011

This issue ofScience in Contextis dedicated to the question of whether there was a “cinematographic turn” in the sciences around the beginning of the twentieth century. In 1895, the Lumière brothers presented their projection apparatus to the Parisian public for the first time. In 1897, the Scottish medical doctor John McIntyre filmed the movement of a frog's leg; in Vienna, in 1898, Ludwig Braun made film recordings of the contractions of a living dog's heart (cf. Cartwright 1992); in 1904, Lucien Bull filmed in slow motion a bullet entering a soap bubble. In 1907 and 1908, respectively, Max Seddig and Victor Henri recorded Brownian motion with the help of a cinematograph (Curtis 2005). In 1909, the Swiss Julius Ries was one of the first to film fertilization and cell division in sea urchins (Ries 1909). In that same year in Paris, Louise Chevroton and Frédéric Vlès used a film camera to observe cell division in the same object (Chevroton and Vlès 1909). As early as 1898, the Parisian surgeon Eugène-Louis Doyen began filming several of his operations, among them the spectacular separation of the Siamese twins Doodica and Radica (Bonah and Laukötter 2009). And in England, the scientist and zoologist Francis Martin Duncan produced an array of popular-scientific films for Charles Urban: “The unseen world: A series of microscopic studies” was presented to the public in the Alhambra Theatre in London for the first time in 1903 (see Gaycken in this issue).
Desired Machines: Cinema and the World in Its Own Image
Authors: Canales Jimena
Published: July 2011

Argument

In 1895 when the Lumière brothers unveiled their cinematographic camera, many scientists were elated. Scientists hoped that the machine would fulfill a desire that had driven research for nearly half a century: that of capturing the world in its own image. But their elation was surprisingly short-lived, and many researchers quickly distanced themselves from the new medium. The cinematographic camera was soon split into two machines, one for recording and one for projecting, enabling it to further escape from the laboratory. The philosopher Henri Bergson joined scientists, such as Etienne-Jules Marey, who found problems with the new cinematographic order. Those who had worked to make the dream come true found that their efforts had been subverted. This essay focuses on the desire to build a cinematographic camera, with the purpose of elucidating how dreams and reality mix in the development of science and technology. It is about desired machines and their often unexpected results. The interplay between what “is” (the technical), what “ought” (the ethical), and what “could” be (the fantastical) drives scientific research.
Creeping, Drinking, Dying: The Cinematic Portal and the Microscopic World of the Twentieth-Century Cell
Authors: Landecker Hannah
Published: July 2011

Argument

Film scholars have long posed the question of the specificity of the film medium and the apparatus of cinema, asking what is unique to cinema, how it constrains and enables filmmakers and audiences in particular ways that other media do not. This question has rarely been considered in relation to scientific film, and here it is posed within the specific context of cell biology: What does the use of time-based media such as film coupled with the microscope allow scientists to experience that other visualization practices do not? Examining three episodes in the twentieth-century study of the cell, this article argues that the apparatus of microcinematography constitutes what might be thought of as a technical portal to another world, a door that determines the experience of the world that lies on the other side of it. In this case, the design of apparatuses to capture time-lapsed images enabled the acceleration of cellular time, bringing it into the realm of human perception and experience. Further, the experience of the cellular temporal world was part of a distinct kind of cell biology, one that was focused on behavior rather than structure, focused on the relation between cells, and between the cell and its milieu rather than on cell-intrinsic features such as chromosomes or organelles. As such, the instruments and technical design of the microcinematographic apparatus may be understood as a kind of materialized epistemology, the history of which can elucidate how cinema was and is used to produce scientific knowledge.
Catheter closure of coronary sinus atrial septal defect using Amplatzer Septal Occluder
Authors: Kijima Yasufumi , Taniguchi Manabu , Akagi Teiji
Published: July 2011

Coronary sinus defect is a rare type of atrial septal defect. We report two patients who had a coronary sinus atrial septal defect without persistent left superior caval vein, where the orifice of the coronary sinus was closed using the Amplatzer Septal Occluder. The procedure was successful, without any complications including conduction disturbance.
Tetralogy of Fallot with double aortic arch
Authors: Harper Andrew Robert , Dai Monica , Prabhatha Rashmi M.
Published: July 2011

An 8 year old girl presents with cyanosis, exertional dyspnoea, and palpitation only. X-ray displayed a typical coeur en sabot heart and auscultsation revealed a harsh ejection systolic murmur. Echocardiography confirmed Tetralogy of Fallot (McGoon ratio 1.3) and computed tomography was requested for further investigation of pulmonary stenosis. A vascular ring was detected, presenting asymptomatically and previously missed through echocardiography. The patient underwent a double-stage repair with ligation of an aortic arch. Recovery was unremarkable. This case highlights the limitations of echocardiography in detection of extra-cardiac anomalies.
Ticuna knowledge, Worecü stars and sky movements
Authors: Faulhaber Priscila
Published: July 2011

This paper focuses on the Ticuna interpretation of the iconography inscribed on ritual artifacts collected by the ethnographer Curt Nimuendaju in the early 1940s. The Ticuna describe certain celestial bodies depicted in the iconography of artifacts that are used in the Ticuna girls' puberty festival as ‘Worecü stars’. They relate these stars to various aspects of indigenous mythology expressed in ritual songs and speeches aboutworecü, a Ticuna word meaning the girl for whom the initiation is being performed. I hold that by incorporating Ticuna mediations into anthropological analysis we enrich this analysis by associating iconic images with mythical meanings transmitted generation by generation through ritual performances in which mythical thinking has the persuasive force of prescriptive action. In thinking about how the Ticuna read the iconography I avoid seeking a strict correlation between Western scientific explanations and the Ticuna's own knowledge about a special star known by them as the Woramacüri star. However, by postulating an association between the Worecü stars and the planets, we can examine the possibility that the Woramacüri Star is correlated with a particular planet at certain times, in specific circumstances.
La Horca del Inca—an astronomical observatory?
Authors: Quiroga Gonzalo Pereira
Published: July 2011

While celebrating the International Year of Astronomy 2009, some government and private institutions in Bolivia pointed out the need to raise a petition to UNESCO and the IAU aimed at declaring the monument known as ‘La Horca del Inca’ (The Inca's Gallows) to be an astronomical World Heritage Site. The request was made because La Horca del Inca was assumed to be a pre-Columbian astronomical observatory. In this paper we analyze the reliability of that postulate through a twofold approach: 1) by examining the most relevant publications, both archaeological and astronomical, that conclude that the site was indeed a pre-Columbian astronomical observatory; and 2) by independently visiting and surveying the monument and its surrounding area.
It's not the End of the World: emic evidence for local diversity in the Maya Long Count
Authors: Van Stone Mark
Published: July 2011

Examining Ancient Maya notions about prophecies and their calendar cycles, we find that they predicted no ‘end of the Maya calendar’. Indeed, surviving texts and art indicate that they seem to have expected no change in the status quo whatever, for at least 4000 years into the future. This search also turned up evidence that different local schools of calendar-priests differed significantly from each other; it is entirely possible that priests in one city expected the End of the World, while their peers elsewhere believed the opposite.
A critical history of 2012 mythology
Authors: Hoopes John W.
Published: July 2011

The notion that December 21, 2012 will bring physical catastrophes, a transformation of consciousness, or even a New Age is an unanticipated and unintentional consequence of early speculation by credentialed academic experts. It has grown as a result of its subsequent interpretation through the lens of speculative, counterculture metaphysics by individuals with both academic and non-academic backgrounds. This article provides a historical review of the most significant contributions to the emergence of the 2012 phenomenon.
The cosmic center in Early China and its archaic resonances
Authors: Pankenier David W.
Published: July 2011

Study of the role of astronomical alignments in shaping the built environment suggests that centuries before establishment of the Empire in 221 BCE, the Chinese had already developed practical, geometrical applications of astronomical knowledge useful in orienting high-value structures. The archaeological record clearly shows this fundamental disposition was already firmly established by the formative period of Chinese civilization in the early 2nd millennium BCE. The cosmological identification of the imperial center with the celestial Pole and an intense focus on the circumpolar ‘skyscape’ are manifested in the highly symbolic orientation of early imperial capitals. Certain features of this cosmological world-view may have emerged as early as the Neolithic.
The archaeoastronomy of the megalithic monuments of Arles–Fontvieille: the equinox, the Pleiades and Orion
Authors: Saletta Morgan
Published: July 2011

The megalithic monuments of Arles–Fontvieille appear to have been deliberately constructed such that a ray of the setting sun on and around the equinox penetrates the subterranean chamber producing a spectacular light-and-shadow hierophany. Moreover, at one of the sites there is evidence in the form of rock art that observations were also being made of heliacal rising and settings, possibly of both the Pleiades and Orion. The equinox hierophany has been documented at three of the four intact monuments of the group. This phenomenon was probably exploited for sacred ritualistic purposes related to seasonal change and timekeeping by the agricultural people who built the monuments. This evidence has significant importance for understanding these monuments in the context of European megalithism and the wider European Neolithic as well as for understanding their cosmological role within the society that built them.
The ‘Ancient Skies’ project—human cultures and their skies
Authors: Schultz Rüdiger , Vickers Doris
Published: July 2011

Human beings have recognized and interpreted celestial objects and events since time immemorial. The sky, our common and universal heritage, forms an integral part of all human cultures around the world. The Ancient Skies Project aims to collect, verify and publish available information about various human cultures and their astronomical knowledge in one single web-accessible knowledgebase.

The overall vision for the project is

In this paper we describe the basic tenets of the project, discuss the design of the knowledgebase, and compare the project to other similar projects.
Gravity wave effects on circulation
Authors: Hamilton Kevin P. , Alexander M. Joan , Sato Kaoru
Published: July 2011

AGU Chapman Conference on Atmospheric Gravity Waves and Their Effects on General Circulation and Climate; Honolulu, Hawaii, 28 February to 4 March 2011; Atmospheric gravity waves account for a significant fraction of the observed variability in the atmosphere with periods from tens of minutes to tens of hours. The wind and temperature variances associated with high‐frequency gravity waves are generally observed to increase with height from near the ground up to the lower thermosphere, and studies of gravity waves in the upper atmosphere have been a staple of middle and upper atmospheric dynamics for many years. Gravity waves act to exchange mean horizontal momentum between the Earth's surface and the atmosphere and among different layers of the atmosphere, and so they play a role in forcing global‐scale atmospheric circulation. Recent work on dynamical coupling of the troposphere with the middle atmosphere has made it clear that gravity waves have a significant influence on the general circulation even in the lower atmosphere, and so global climate simulation models need to adequately treat the effects of atmospheric gravity waves that are not explicitly resolved.
Measuring global temperatures: Their analysis and interpretation
Authors: Pielke Roger A.
Published: July 2011

This book documents how global surface temperature anomalies (GSTAs) and multidecadal trends are obtained. While ocean heat content change is a more robust metric with which to diagnose global warming, GSTAs have become a primary icon in the climate change debate. The book begins with a brief overview chapter of the Earth's radiative energy budget followed by two chapters on measurement approaches to monitoring temperature, including an interesting discussion of temperature scales. Chapters 4–6 concern measuring land and ocean temperatures. Chapters 7 and 8 discuss global networks and how point measurements are converted to obtain global averages. Chapter 9 focuses on changes in time of temperatures, including maximum and minimum values. This is followed by a short chapter on temperature profiles through the atmosphere and a final chapter of recommendations for future observations of this metric.
Explaining away El Niño Modoki
Authors: Schultz Colin
Published: July 2011

The traditional view of El Niño is that it starts with a warm sea surface anomaly off the west coast of South America. This aberrant warming drifts west from the coast, triggering peak sea surface temperatures in the central Pacific during the southern summer. However, as the observational record grows and the full range of variability comes into view, some researchers have suggested that a recent slate of El Niño events that focus on the central Pacific, skipping the eastern warming, indicates that the system is composed of at least two unique climate dynamics. The central Pacific‐focused El Niño Modoki has been increasing in prevalence over recent decades, and researchers expect this trend to continue with global warming. New research by Takahashi et al., however, indicates that El Niño Modoki and the classical type are in fact one but that the perceived divergent behavior highlights the dynamic range of the system. Using El Niño observations stretching back to 1870, the authors performed a statistical analysis, breaking down the data set to isolate hidden spatial and temporal patterns. The Modoki and traditional El Niño records did not show the clustering that would be expected for separate climate phenomena. What did stand out, however, were the extreme warm events that occurred in the eastern Pacific in 1982–1983 and 1997–1998. (Geophysical Research Letters, doi:10.1029/2011GL047364, 2011)
Energy dissipation mechanisms in wave breaking processes: Spilling and highly aerated plunging breaking events
Authors: Iafrati A.
Published: July 2011

The breaking of free surface waves is investigated numerically via a Navier‐Stokes model for the two‐fluids flow of air and water. Third order Stokes waves in a periodic domain are simulated. The fundamental wavelength is 27 cm, whereas the initial steepness varies from low values, leading to regular wave trains, up to artificially steep wave trains yielding plunging breaking events. Attention is focused on the early stage of the breaking, when most of the energy is dissipated. The energy content in air, the fraction associated to surface tension effects, the viscous dissipation in water, and the work done against the pressure field are analyzed in order to distinguish the different contributions to the dissipation. Vorticity fields and dissipation contours are also presented. In the spilling case, the extra energy content with respect to the steepest nonbreaking case focusses into the breaking region and is gradually dissipated. Once the extra energy has been dissipated, the resulting wave matches the steepest nonbreaking solution. In the plunging case, an important role is played by the air entrainment. A fraction between 10 to 35% of the energy dissipated by the breaking is spent in entraining the air cavity, and most of it is dissipated by viscous effects when the cavity collapses. The phenomenon is clearly highlighted by sequences of vorticity and dissipation contours. The circulation and the area of the cavity generated by the plunging of the jet are provided, and parametric dependencies are proposed.
The mitochondrial citrate carrier: a new player in inflammation
Authors: Infantino Vittoria , Convertini Paolo , Cucci Liana , Panaro Maria Antonietta , Di Noia Maria Antonietta , Calvello Rosa , Palmieri Ferdinando , Iacobazzi Vito
Published: July 2011

The mitochondrial CIC (citrate carrier) catalyses the efflux of citrate from the mitochondrial matrix in exchange for cytosolic malate. In the present paper we show that CIC mRNA and protein markedly increase in lipopolysaccharide-activated immune cells. Moreover, CIC gene silencing and CIC activity inhibition significantly reduce production of NO, reactive oxygen species and prostaglandins. These results demonstrate for the first time that CIC has a critical role in inflammation.
Diabetes as a risk factor for Alzheimer's disease: insulin signalling impairment in the brain as an alternative model of Alzheimer's disease
Authors: Hölscher Christian
Published: July 2011

Surprisingly little is known about the mechanisms that trigger the onset of AD (Alzheimer's disease) in sporadic forms. A number of risk factors have been identified that may shed light on the mechanisms that may trigger or facilitate the development of AD. Recently, T2DM (Type 2 diabetes mellitus) has been identified as a risk factor for AD. A common observation for both conditions is the desensitization of insulin receptors in the brain. Insulin acts as a growth factor in the brain and is neuroprotective, activates dendritic sprouting, regeneration and stem cell proliferation. The impairment of this important growth factor signal may facilitate the development of AD. Insulin as well as other growth factors have shown neuroprotective properties in preclinical and clinical trials. Several drugs have been developed to treat T2DM, which re-sensitize insulin receptors and may be of use to prevent neurodegenerative processes in the brain. In particular, the incretins GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insolinotropic polypeptide) are hormones that re-sensitize insulin signalling. Incretins also have similar growth-factor-like properties as insulin and are neuroprotective. In mouse models of AD, GLP-1 receptor agonists reduce amyloid plaque formation, reduce the inflammation response in the brain, protect neurons from oxidative stress, induce neurite outgrowth, and protect synaptic plasticity and memory formation from the detrimental effects caused by β-amyloid production and inflammation. Other growth factors such as BDNF (brain-derived neurotrophic factor), NGF (nerve growth factor) or IGF-1 (insulin-like growth factor 1) also have shown a range of neuroprotective properties in preclinical studies. These results show that these growth factors activate similar cell signalling mechanisms that are protective and regenerative, and suggest that the initial process that may trigger the cascade of neurodegenerative events in AD could be the impairment of growth factor signalling such as early insulin receptor desensitization.
Modelling early responses to neurodegenerative mutations in mice
Authors: Gilley Jonathan , Adalbert Robert , Coleman Michael P.
Published: July 2011

Considering the many differences between mice and humans, it is perhaps surprising how well mice model late-onset human neurodegenerative disease. Models of Alzheimer's disease, frontotemporal dementia, Parkinson's disease and Huntington's disease show some striking similarities to the corresponding human pathologies in terms of axonal transport disruption, protein aggregation, synapse loss and some behavioural phenotypes. However, there are also major differences. To extrapolate from mouse models to human disease, we need to understand how these differences relate to intrinsic limitations of the mouse system and to the effects of transgene overexpression. In the present paper, we use examples from an amyloid-overexpression model and a mutant-tau-knockin model to illustrate what we learn from each type of approach and what the limitations are. Finally, we discuss the further contributions that knockin and similar approaches can make to understanding pathogenesis and how best to model disorders of aging in a short-lived mammal.
‘Alzheimer-like’ pathology in a murine model of arterial hypertension
Authors: Carnevale Daniela , Lembo Giuseppe
Published: July 2011

Genetic AD (Alzheimer's disease) accounts for only few AD cases and is almost exclusively associated with increased amyloid production in the brain. Instead, most patients are affected with the sporadic form of AD and typically have altered clearance mechanisms. The identification of factors that influence the onset and progression of sporadic AD is a key step towards understanding its mechanism(s) and developing successful therapies. An increasing number of epidemiological studies describe a strong association between AD and cardiovascular risk factors, particularly hypertension, that exerts detrimental effects on the cerebral circulation, favouring chronic brain hypoperfusion. However, a clear demonstration of a pathophysiological link between cardiovascular risk factors and AD aetiology is still missing. To increase our knowledge of the mechanisms involved in the brain's response to hypertension and their possible role in promoting amyloid deposition in the brain, we have performed and investigated in depth different murine models of hypertension, induced either pharmacologically or mechanically, leading in the long term to plaque formation in the brain parenchyma and around blood vessels. In the present paper, we review the major findings in this particular experimental setting that allow us to study the pathogenetic mechanisms of sporadic AD triggered by vascular risk factors.
The role of mutant TAR DNA-binding protein 43 in amyotrophic lateral sclerosis and frontotemporal lobar degeneration
Authors: Janssens Jonathan , Kleinberger Gernot , Wils Hans , Van Broeckhoven Christine
Published: July 2011

TDP-43 (TAR DNA-binding protein 43) has been identified as a key protein of ubiquitinated inclusions in brains of patients with ALS (amyotrophic lateral sclerosis) or FTLD (frontotemporal lobar degeneration), defining a new pathological disease spectrum. Recently, coding mutations have been identified in the TDP-43 gene (TARDBP), which further confirmed the pathogenic nature of the protein. Today, several animal models have been generated to gain more insight into the disease-causing pathways of the FTLD/ALS spectrum. This mini-review summarizes the current status of TDP-43 models, with a focus on mutant TDP-43.
Ovocalyxin-36 and other LBP/BPI/PLUNC-like proteins as molecular actors of the mechanisms of the avian egg natural defences
Authors: Gautron Joël , Réhault-Godbert Sophie , Pascal Géraldine , Nys Yves , Hincke Maxwell T.
Published: July 2011

The chicken egg possesses physical and chemical barriers to protect the embryo from pathogens. OCX-36 (ovocalyxin-36) was suggested to be a 36 kDa eggshell-specific protein that is secreted by the regions of the oviduct responsible for eggshell formation. Its expression is strongly up-regulated during shell calcification. This protein was also detected in vitelline membrane and expressed in gut tissues. Analysis of the OCX-36 protein sequence revealed that OCX-36 is related to the BPI (bactericidal permeability-increasing proteins)/LBP [LPS (lipopolysaccharide)-binding proteins]/PLUNC (palate, lung and nasal epithelium clone) superfamily, and that there are strong similarities between the exon/intron organization of the mammalian LBP/BPI and the avian OCX-36 genes. A recent study revealed that OCX-36 originates from a tandem duplication of an ancestral BPI/LBP/PLUNC gene, after the divergence of birds and mammals. Its antimicrobial activity was recently investigated and it was shown that OCX-36 binds to LPS from Escherichia coli. High-throughput methodologies have led to the identification of approximately 1000 new egg proteins. Among these are LBP/BPI proteins that might play a role in the natural defences of the egg to protect the embryo during its development in the external milieu, and may function to keep the table egg free of pathogens. The function of these BPI-like molecules is the subject of intense research to characterize their putative LPS-binding properties and antimicrobial activity.
Deficient expression of bactericidal/permeability-increasing protein in immunocompromised hosts: translational potential of replacement therapy
Authors: Palmer Christine D. , Guinan Eva C. , Levy Ofer
Published: July 2011

BPI (bactericidal/permeability-increasing protein) is a 55 kDa anti-infective molecule expressed in neutrophil and eosinophil granules and on some epithelial cells. BPI's high affinity for the lipid A region of endotoxin targets its opsonizing, microbicidal and endotoxin-neutralizing activities towards Gram-negative bacteria. Several immunocompromised patient populations demonstrate BPI deficiency, including newborns, those with anti-neutrophil cytoplasmic antibodies (as in cystic fibrosis and HIV infection) and those exposed to radiochemotherapy. BPI may be replenished by administering agents that induce its expression or by administration of recombinant BPI congeners, potentially shielding BPI-deficient individuals against Gram-negative bacterial infection, endotoxemia and its toxic sequelae.
PLUNC: a multifunctional surfactant of the airways
Authors: Bartlett Jennifer , Gakhar Lokesh , Penterman Jon , Singh Pradeep , Mallampalli Rama K. , Porter Edith , McCray Paul B.
Published: July 2011

PLUNC (palate, lung and nasal epithelium clone) protein is an abundant secretory product of epithelia throughout the mammalian conducting airways. Despite its homology with the innate immune defence molecules BPI (bactericidal/permeability-increasing protein) and LBP (lipopolysaccharide-binding protein), it has been difficult to define the functions of PLUNC. Based on its marked hydrophobicity and expression pattern, we hypothesized that PLUNC is an airway surfactant. We found that purified recombinant human PLUNC exhibited potent surfactant activity by several different measures, and experiments with airway epithelial cell lines and primary cultures indicate that native PLUNC makes a significant contribution to the overall surface tension in airway epithelial secretions. Interestingly, we also found that physiologically relevant concentrations of PLUNC-inhibited Pseudomonas aeruginosa biofilm formation in vitro without acting directly as a bactericide. This finding suggests that PLUNC protein may inhibit biofilm formation by airway pathogens, perhaps through its dispersant properties. Our data, along with reports from other groups on activity against some airway pathogens, expand on an emerging picture of PLUNC as a multifunctional protein, which plays a novel role in airway defences at the air/liquid interface.
Latherin and other biocompatible surfactant proteins
Authors: Kennedy Malcolm W.
Published: July 2011

Horses and other equids are unusual in producing protein-rich sweat for thermoregulation, a major component of which is latherin, a highly surface-active, non-glycosylated protein that is a member of the PLUNC (palate, lung and nasal epithelium clone) family. Latherin produces a significant reduction in water surface tension at low concentrations (≤1 mg/ml), and probably acts as a wetting agent to facilitate evaporative cooling through a thick, waterproofed pelt. Latherin binds temporarily to hydrophobic surfaces, and so may also have a disruptive effect on microbial biofilms. It may consequently have a dual role in horse sweat in both evaporative cooling and controlling microbial growth in the pelt that would otherwise be resourced by nutrients in sweat. Latherin is also present at high levels in horse saliva, where its role could be to improve mastication of the fibrous diet of equids, and also to reduce microbial adherence to teeth and oral surfaces. Neutron reflection experiments indicate that latherin adsorbs to the air/water interface, and that the protein undergoes significant conformational change and/or partial unfolding during incorporation into the interfacial layer.
Bioinformatics of the TULIP domain superfamily
Authors: Kopec Klaus O. , Alva Vikram , Lupas Andrei N.
Published: July 2011

Proteins of the BPI (bactericidal/permeability-increasing protein)-like family contain either one or two tandem copies of a fold that usually provides a tubular cavity for the binding of lipids. Bioinformatic analyses show that, in addition to its known members, which include BPI, LBP [LPS (lipopolysaccharide)-binding protein)], CETP (cholesteryl ester-transfer protein), PLTP (phospholipid-transfer protein) and PLUNC (palate, lung and nasal epithelium clone) protein, this family also includes other, more divergent groups containing hypothetical proteins from fungi, nematodes and deep-branching unicellular eukaryotes. More distantly, BPI-like proteins are related to a family of arthropod proteins that includes hormone-binding proteins (Takeout-like; previously described to adopt a BPI-like fold), allergens and several groups of uncharacterized proteins. At even greater evolutionary distance, BPI-like proteins are homologous with the SMP (synaptotagmin-like, mitochondrial and lipid-binding protein) domains, which are found in proteins associated with eukaryotic membrane processes. In particular, SMP domain-containing proteins of yeast form the ERMES [ER (endoplasmic reticulum)-mitochondria encounter structure], required for efficient phospholipid exchange between these organelles. This suggests that SMP domains themselves bind lipids and mediate their exchange between heterologous membranes. The most distant group of homologues we detected consists of uncharacterized animal proteins annotated as TM (transmembrane) 24. We propose to group these families together into one superfamily that we term as the TULIP (tubular lipid-binding) domain superfamily.
The bactericidal/permeability-increasing protein (BPI) in the innate defence of the lower airways
Authors: Holweg Alexander , Schnare Markus , Gessner André
Published: July 2011

The human BPI (bactericidal/permeability-increasing protein), stored in primary azurophilic granula of neutrophil granulocytes and produced by mucosal epithelia, has been known for decades to bind LPS (lipopolysaccharide) with very high affinity and to efficiently kill Gram-negative bacteria. Thus BPI potentially represents a central component of the innate immune system to directly combat microbes and modulate subsequent adaptive immune responses. Especially in the lungs, which are frequently exposed to a variety of inhaled pathogens, antimicrobial innate defence molecules such as BPI, are of exceptional relevance. In the present review, we highlight possible functions of BPI during acute pneumonia and CF (cystic fibrosis)-associated chronic infections in the lung.
Intestinal secretory cell ER stress and inflammation
Authors: McGuckin Michael A. , Eri Rajaraman D. , Das Indrajit , Lourie Rohan , Florin Timothy H.
Published: July 2011

Data from animal models and human inflammatory bowel diseases have implicated the ER (endoplasmic reticulum) stress pathway in intestinal inflammation. We have characterized the development of inflammation in Winnie mice in which ER stress arises due to a single missense mutation in the MUC2 mucin produced by intestinal goblet cells. This model has allowed us to explore the genesis of inflammation ensuing from a single gene polymorphism affecting secretory cells. In these mice, a proportion of MUC2 misfolds during biosynthesis, leading to ER stress and activation of the unfolded protein response. Winnie mice develop spontaneous complex progressive inflammation that is most severe in the distal colon. Inflammation involves TH1, TH2 and TH17 T-cells, with a progressive development of a TH17-dominated response, but also involves innate immunity, in a pattern not dissimilar to human colitis. Experimental inhibition of tolerance in this model severely exacerbates colitis, demonstrating active effective suppression of inflammation. Even though the misfolding of MUC2 is a consequence of an inherited mutation, as inflammation develops, the molecular markers of ER stress increase further and goblet cell pathology becomes worse, suggesting that inflammation itself exacerbates ER stress.
Nuclear magnetic resonance shielding constants and chemical shifts in linear 199Hg compounds: A comparison of three relativistic computational methods
Authors: Arcisauskaite Vaida , Melo Juan I. , Hemmingsen Lars , Sauer Stephan P. A.
Published: July 2011

We investigate the importance of relativistic effects on NMR shielding constants and chemical shifts of linear HgL2 (L = Cl, Br, I, CH3) compounds using three different relativistic methods: the fully relativistic four-component approach and the two-component approximations, linear response elimination of small component (LR-ESC) and zeroth-order regular approximation (ZORA). LR-ESC reproduces successfully the four-component results for the C shielding constant in Hg(CH3)2 within 6 ppm, but fails to reproduce the Hg shielding constants and chemical shifts. The latter is mainly due to an underestimation of the change in spin-orbit contribution. Even though ZORA underestimates the absolute Hg NMR shielding constants by ∼2100 ppm, the differences between Hg chemical shift values obtained using ZORA and the four-component approach without spin-density contribution to the exchange-correlation (XC) kernel are less than 60 ppm for all compounds using three different functionals, BP86, B3LYP, and PBE0. However, larger deviations (up to 366 ppm) occur for Hg chemical shifts in HgBr2 and HgI2 when ZORA results are compared with four-component calculations with non-collinear spin-density contribution to the XC kernel. For the ZORA calculations it is necessary to use large basis sets (QZ4P) and the TZ2P basis set may give errors of ∼500 ppm for the Hg chemical shifts, despite deceivingly good agreement with experimental data. A Gaussian nucleus model for the Coulomb potential reduces the Hg shielding constants by ∼100–500 ppm and the Hg chemical shifts by 1–143 ppm compared to the point nucleus model depending on the atomic number Z of the coordinating atom and the level of theory. The effect on the shielding constants of the lighter nuclei (C, Cl, Br, I) is, however, negligible.
Temperature and methanol concentration dependences of direct methanol fuel cell performance measured by single cell having reference electrode
Authors: Umeda Minoru , Sayama Kazuya , Inoue Mitsuhiro
Published: July 2011

In this study, we measured the cell temperature and methanol concentration dependences of direct methanol fuel cell (DMFC) performances and its polarization characteristics using a single cell with a Ag/Ag2SO4 reference electrode, which has been developed for the DMFC research in our laboratory. The membrane electrode assembly composed of carbon-supported Pt-Ru and Pt catalysts and the Nafion membrane was used for the measurements. As a result, the power densities obtained while feeding 1 and 5 mol dm−3 methanol solutions increase in the order of 26, 40, and 60 °C. For the 10 mol dm−3 methanol, the power density at 60 °C is lower than those at 26 and 40 °C. In these cases, the polarization curves to investigate the details of the relationship between the DMFC performance and temperature indicate that for the 1 and 5 mol dm−3 methanol, the current densities measured at the same anode and cathode potentials are enhanced with the increasing temperature. As for the 10 mol dm−3 methanol, the current densities at the anode and cathode decrease at 60 °C. To clarify a reason for the particular results of the 10 mol dm−3 methanol, the DMFC performances and the polarization curves at 40 and 60 °C were compared as a function of the methanol concentration. These results demonstrate that the decrease in the DMFC performance at 60 °C by feeding 10 mol dm−3 methanol is attributed to the simultaneous appearance of the O2 crossleak and methanol crossover causing the decline in the methanol oxidation performance at the anode and O2 reduction performance at the cathode.
A new low-cost 10 ns pulsed Ka-band radar
Authors: Eskelinen Pekka , Ylinen Juhana
Published: July 2011

Two Gunn oscillators, conventional intermediate frequency building blocks, and a modified GaAs diode detector are combined to form a portable monostatic 10 ns instrumentation radar for outdoor Ka-band radar cross section measurements. At 37.8 GHz the radar gives +20 dBm output power and its tangential sensitivity is –76 dBm. Processing bandwidth is 125 MHz, which also allows for some frequency drift in the Gunn devices. Intra-pulse frequency chirp is less than 15 MHz. All functions are steered by a microcontroller. First measurements convince that the construction has a reasonable ability to reduce close-to-ground surface clutter and gives an effective way of resolving target detail. This is beneficial especially when amplitude fluctuations disturb measurements with longer pulses. The new unit operates on 12 V dc, draws a current of less than 3 A, and weighs 5 kg.