bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulating iron storage and metabolism with RNA: an overview of posttranscriptional controls of intracellular iron homeostasis
Authors: Salvail Hubert , Massé Eric 
Published: July 2011

AbstractIron (Fe) is a double‐edged sword for most living organisms. Although it is essential for the catalytic activity of a large number of enzymes, ferrous iron (Fe2+) becomes cytotoxic in the presence of normal respiratory by‐products such as H2O2. Because of this toxicity, intracellular iron concentrations ought to be regulated by elaborated homeostasis systems that, despite decades of extensive studies, have not yet revealed all of their surprising arrays of mechanistic details. Within the last few years, our understanding of iron metabolism has revealed that posttranscriptional regulation represents a major contribution to iron homeostasis in a host of organisms. While the small RNA RyhB regulates iron homeostasis in bacteria, its functional homolog protein Cth2 performs a similar task in yeasts. Recent advances in the elucidation of the mechanism of action and functions of RyhB have been made in Escherichia coli. In addition, other RyhB‐like small RNAs have been identified in several bacterial species, such as Pseudomonas aeruginosa, Salmonella enterica, Vibrio cholerae, Neisseria meningitidis, and Shigella spp. These recent findings have shed light on the complexity of iron homeostasis. WIREs RNA 2012, 3:26–36. doi: 10.1002/wrna.102This article is categorized under:

Translation > Translation Regulation
RNA Turnover and Surveillance > Regulation of RNA Stability
Regulatory RNAs/RNAi/Riboswitches > Regulatory RNAs
RNA in Disease and Development > RNA in Disease
LiSr2[TaN3]F – a Single Chain Nitridotantalate
Authors: Pust Philipp , Schnick Wolfgang 
Published: July 2011

AbstractThe chain type nitridotantalate LiSr2[TaN3]F was synthesized by reaction of strontium with AlF3, Eu(NH2)2, LiN3 and lithium metal as fluxing agent in weld shut tantalum ampoules. Single crystals were obtained as byproduct from reaction with the ampoule material. The crystal structure (Pbca (no. 61), a = 10.768(2), b = 5.5913(11), c = 15.891(3) Å, Z = 8) was solved on the basis of single‐crystal X‐ray diffraction data. LiSr2[TaN3]F contains infinite chains of vertex sharing TaN4 tetrahedra running along [010]. The structure can be understood as an intercalation of Li+ and F– into Sr2TaN3. Lattice energy calculations (MAPLE) and EDX measurements confirmed the electrostatic bonding interactions and the chemical composition.
Synthesis, Structures, and Photophysics of Polynuclear Silver(I) Thiolate and Silver(I) Thiocarboxylate Complexes with Dppm Ligands
Authors: Chao Hsiu‐Yi , Wu Li , Li Cheng‐Luan , Lu Wei , Liu Li , Feng Xiao‐Long 
Published: July 2011

AbstractTrinuclear silver(I) thiolate and silver(I) thiocarboxylate complexes [Ag3(μ‐dppm)3(μn‐SR)2](ClO4) [n = 2, R = C6H4Cl‐4 (1) and C{O}Ph (2); n = 3, R = tBu (3)], pentanuclear silver(I) thiolate complex [Ag5(μ‐dppm)4(μ3‐SC6H4NO2‐4)4](PF6) (4), and hexanuclear silver(I) thiolate complexes [Ag6(μ‐dppm)4(μ3‐SR)4]Y2 [Y = ClO4, R =C6H4CH3‐4 (5) and C10H7 (2‐naphthyl) (7); Y = PF6, R = C6H4OCH3‐4(6)], were synthesized [dppm = bis(diphenylphosphanyl)methane] and their crystal structures as well as photophysical properties were studied. In the solid state at 77 K, trinuclear silver(I) thiolate and silver(I) thiocarboxylate complexes 1 and 2 exhibit luminescence at 470–523 nm, tentatively attributed to originate from the 3IL (intraligand) of thiolate or thiocarboxylate ligands, whereas hexanuclaer silver(I) thiolate complexes 5 and 7 produce dual emission, in which high‐energy emission is tentatively attributed to come from the 3IL of thiolate ligands and low‐energy emission is tentatively assigned to come from the admixture of metal···metal bond‐to‐ligand charge‐transfer (MMLCT) and metal‐centered (MC) excited states.
Measuring Latent Quantities
Authors: McDonald Roderick P. 
Published: July 2011

A distinction is proposed between measures and predictors of latent variables. The discussion addresses the consequences of the distinction for the true-score model, the linear factor model, Structural Equation Models, longitudinal and multilevel models, and item-response models. A distribution-free treatment of calibration and error-of-measurement is given, and the contrasting properties of measures and predictors are examined.
Management of chronic pain among older patients: Inside primary care in the US
Authors: Tai‐Seale Ming , Bolin Jane , Bao Xiaoming , Street Richard 
Published: July 2011

AbstractUnder‐treatment of pain is a worldwide problem. We examine how often pain was addressed and the factors that influence how much time was spent on treating pain.We analyzed 385 videotapes of routine office visits in several primary care practices in the Southwest and Midwest regions of the United States. We coded the visit contents and the time spent on pain and other topics. Logistic regression and survival analyses examined the effects of time constraint, physician's supportiveness, patient's health, and demographic concordance. We found that discussion of pain occurred in 48% of visits. A median of 2.3 min was spent on addressing pain. The level of pain, physician's supportiveness, and gender concordance were significantly associated with the odds of having a pain discussion. Time constraints and racial concordance significantly influenced the length of discussion.We conclude that despite repeated calls for addressing under‐treatment for pain, only a limited amount of time is used to address pain among elderly patients. This phenomenon could contribute to the under‐treatment of pain.
Volumetric and visual rating of magnetic resonance imaging scans in the diagnosis of amnestic mild cognitive impairment and Alzheimer's disease
Authors: Shen Qian , Loewenstein David A. , Potter Elizabeth , Zhao Weizhao , Appel Jason , Greig Maria T. , Raj Ashok , Acevedo Amarilis , Schofield Elizabeth , Barker Warren , Wu Yougui , Potter Huntington , Duara Ranjan 
Published: July 2011

BackgroundIn the diagnosis of Alzheimer's disease (AD), structural magnetic resonance imaging (MRI) scans have been used primarily to exclude non‐Alzheimer's causes of dementia. However, the pattern and the extent of medial temporal atrophy on structural MRI scans, which correlate strongly with the pathological severity of AD, can be used to support the diagnosis of a degenerative dementia, especially AD, even in its early predementia stage.MethodsElderly subjects (n = 224) were diagnosed with either no cognitive impairment (NCI), amnestic mild cognitive impairment (aMCI), or AD. Hippocampal and hemispheric gray matter volumes were measured on structural MRI scans, and a new visual rating system was used to score the severity of medial temporal atrophy (VRS‐MTA) of the hippocampus (HPC), entorhinal cortex, and perirhinal cortex on a coronal image intersecting the mammillary bodies.ResultsAlthough both VRS‐MTA scores and HPC volumes distinguished between subjects with NCI, aMCI, and AD, subjects with aMCI and NCI could be better distinguished using right VRS‐MTA scores, in comparison with right HPC volumes. VRS‐MTA scores were more highly correlated with episodic memory and Clinical Dementia Rating scores. A combination of left sided VRS‐MTA scores and left sided hippocampal volume was the most predictive measure of diagnostic classification.ConclusionVRS‐MTA is a clinically convenient method or distinguishing aMCI or AD from NCI. As compared with volumetric measures, it provides better discriminatory power and correlates more strongly with memory and functional scores.
Steps to standardization and validation of hippocampal volumetry as a biomarker in clinical trials and diagnostic criterion for Alzheimer's disease
Authors: Jack Clifford R. , Barkhof Frederik , Bernstein Matt A. , Cantillon Marc , Cole Patricia E. , DeCarli Charles , Dubois Bruno , Duchesne Simon , Fox Nick C. , Frisoni Giovanni B. , Hampel Harald , Hill Derek L.G. , Johnson Keith , Mangin Jean‐François , Scheltens Philip , Schwarz Adam J. , Sperling Reisa , Suhy Joyce , Thompson Paul M. , Weiner Michael , Foster Norman L. 
Published: July 2011

BackgroundThe promise of Alzheimer's disease biomarkers has led to their incorporation in new diagnostic criteria and in therapeutic trials; however, significant barriers exist to widespread use. Chief among these is the lack of internationally accepted standards for quantitative metrics. Hippocampal volumetry is the most widely studied quantitative magnetic resonance imaging measure in Alzheimer's disease and thus represents the most rational target for an initial effort at standardization.Methods and ResultsThe authors of this position paper propose a path toward this goal. The steps include the following: (1) Establish and empower an oversight board to manage and assess the effort, (2) adopt the standardized definition of anatomic hippocampal boundaries on magnetic resonance imaging arising from the European Alzheimer's Disease Centers–Alzheimer's Disease Neuroimaging Initiative hippocampal harmonization effort as a reference standard, (3) establish a scientifically appropriate, publicly available reference standard data set based on manual delineation of the hippocampus in an appropriate sample of subjects (Alzheimer's Disease Neuroimaging Initiative), and (4) define minimum technical and prognostic performance metrics for validation of new measurement techniques using the reference standard data set as a benchmark.ConclusionsAlthough manual delineation of the hippocampus is the best available reference standard, practical application of hippocampal volumetry will require automated methods. Our intent was to establish a mechanism for credentialing automated software applications to achieve internationally recognized accuracy and prognostic performance standards that lead to the systematic evaluation and then widespread acceptance and use of hippocampal volumetry. The standardization and assay validation process outlined for hippocampal volumetry was envisioned as a template that could be applied to other imaging biomarkers.
The underlying mechanism for the PARP and BRCA synthetic lethality: Clearing up the misunderstandings
Authors: Helleday Thomas 
Published: July 2011

AbstractPoly (ADP‐ribose) polymerase (PARP) inhibitors effectively kill tumours defective in the BRCA1 or BRCA2 genes through the concept of synthetic lethality. It is suggested that PARP inhibitors cause an increase in DNA single‐strand breaks (SSBs), which are converted during replication to irreparable toxic DNA double‐strand breaks (DSBs) in BRCA1/2 defective cells. There are a number of recent reports challenging this model. Here, alternative models that are not mutually exclusive are presented to explain the synthetic lethality between BRCA1/2 and PARP inhibitors. One such model proposes that PARP inhibition causes PARP‐1 to be trapped onto DNA repair intermediates, especially during base excision repair. This may in turn cause obstruction to replication forks, which require BRCA‐dependent homologous recombination to be resolved. In another model, PARP is directly involved in catalysing replication repair in a distinct pathway from homologous recombination. Experimental evidence supporting these novel models to explain the PARP‐BRCA synthetic lethality are discussed.
TASTE AND CLASS IN LATE OTTOMAN BEIRUT
Authors: Abou-Hodeib Toufoul 
Published: July 2011

AbstractThis 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

SUMMARYThis 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

SUMMARYKinematic 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.
Desired Machines: Cinema and the World in Its Own Image
Authors: Canales Jimena 
Published: July 2011

ArgumentIn 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

ArgumentFilm 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

AbstractCoronary 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

AbstractAn 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

AbstractThis 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

AbstractWhile 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

AbstractExamining 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

AbstractThe 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

AbstractStudy 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.