Miracle-dz/UniFAR-FTUs huggingface dataset:
A Deep Chandra Observation of Abell 4059: A New Face to “Radio-Mode” AGN Feedback?

A deep Chandra observation of the cooling core cluster Abell 4059 (A4059) is presented. Previous studies have found two X-ray cavities in the central regions of A4059 together with a ridge of X-ray emission 20 kpc southwest of the cluster center. These features are clearly related to the radio galaxy PKS 2354–35, which resides in the cD galaxy. Our new data confirm these previous findings and strengthen previous suggestions that the southwestern ridge is colder and denser than, but in approximate pressure equilibrium with, the surrounding ICM atmosphere. In addition, we find evidence for a weak shock that wraps around the north and east sides of the cavity structure. Our data allow us to map the two-dimensional (2D) distribution of metals in the ICM of A4059 for the first time. We find that the southwest ridge possesses an anomalously high (supersolar) metallicity. The unusual morphology, temperature structure, and metal distribution all point to significant asymmetry in the ICM atmosphere prior to the onset of radio galaxy activity. Motivated by the very high metallicity of the southwest ridge, we hypothesize that the ICM asymmetry was caused by the extremely rapid stripping of metal-enriched gas from a starburst galaxy that plunged through the core of A4059. Furthermore, we suggest that the onset of powerful radio galaxy activity in the cD galaxy may have been initiated by this starburst/stripping event, via either the tidal shocking of cold gas native to the cD galaxy or the accretion of cold gas that had been stripped from the starburst galaxy.
Drivers of community participation in heritage tourism planning: an empirical investigation

ABSTRACT Despite increased emphasis on community participation in tourism planning, our current knowledge of community attitudes and their motivations to engage in such collaborative governance is limited and fragmented. This paper explores the role of heritage values, tourism and community perceptions held by destination hosts as drivers to willingness to participate in heritage tourism development. Such enquiry aims to enhance our current knowledge of community views and their potential to influence involvement in participatory decision-making in order to inform policy approaches to collaborative heritage tourism strategies. Using a relatively inexperienced destination community (Kastoria, Greece), the study collects quantitative data via an attitudinal survey. Our findings suggest that intentions to participate are mainly driven by community ideals while their positive influence is more evident on community members with high place attachment. Heritage values play a significant role; however, their effects do not always favour participation as they can also act as barriers to involvement. On the other hand, tourism perceptions are found to be mainly insignificant in shaping intentions to participate. Finally, the paper presents and discusses variations between different demographic groups and draws implications for policy.
Comparative Genomics Reveals Adaptation by Alteromonas sp. SN2 to Marine Tidal-Flat Conditions: Cold Tolerance and Aromatic Hydrocarbon Metabolism

Alteromonas species are globally distributed copiotrophic bacteria in marine habitats. Among these, sea-tidal flats are distinctive: undergoing seasonal temperature and oxygen-tension changes, plus periodic exposure to petroleum hydrocarbons. Strain SN2 of the genus Alteromonas was isolated from hydrocarbon-contaminated sea-tidal flat sediment and has been shown to metabolize aromatic hydrocarbons there. Strain SN2's genomic features were analyzed bioinformatically and compared to those of Alteromonas macleodii ecotypes: AltDE and ATCC 27126. Strain SN2's genome differs from that of the other two strains in: size, average nucleotide identity value, tRNA genes, noncoding RNAs, dioxygenase gene content, signal transduction genes, and the degree to which genes collected during the Global Ocean Sampling project are represented. Patterns in genetic characteristics (e.g., GC content, GC skew, Karlin signature, CRISPR gene homology) indicate that strain SN2's genome architecture has been altered via horizontal gene transfer (HGT). Experiments proved that strain SN2 was far more cold tolerant, especially at 5°C, than the other two strains. Consistent with the HGT hypothesis, a total of 15 genomic islands in strain SN2 likely confer ecological fitness traits (especially membrane transport, aromatic hydrocarbon metabolism, and fatty acid biosynthesis) specific to the adaptation of strain SN2 to its seasonally cold sea-tidal flat habitat.
A comparative study of motor-protein motions by using a simple elastic-network model

In this work, we report on a study of the structure-function relationships for three families of motor proteins, including kinesins, myosins, and F1-ATPases, by using a version of the simple elastic-network model of large-scale protein motions originally proposed by Tirion [Tirion, M. (1996) Phys. Rev. Lett. 77, 1905–1908]. We find a surprising dichotomy between kinesins and the other motor proteins (myosins and F1-ATPase). For the latter, there exist one or two dominant lowest-frequency modes (one for myosin, two for F1-ATPase) obtained from normal-mode analysis of the elastic-network model, which overlap remarkably well with the measured conformational changes derived from pairs of solved crystal structures in different states. Furthermore, we find that the computed global conformational changes induced by the measured deformation of the nucleotide-binding pocket also overlap well with the measured conformational changes, which is consistent with the “nucleotide-binding-induced power-stroke” scenario. In contrast, for kinesins, this simplicity breaks down. Multiple modes are needed to generate the measured conformational changes, and the computed displacements induced by deforming the nucleotide-binding pocket also overlap poorly with the measured conformational changes, and are insufficient to explain the large-scale motion of the relay helix and the linker region. This finding may suggest the presence of two different mechanisms for myosins and kinesins, despite their strong evolutionary ties and structural similarities.
Association of k-ras, b-raf, and p53 status with the treatment effect of bevacizumab.

BACKGROUND A recent phase III trial showed that the addition of bevacizumab, a monoclonal antibody to vascular endothelial growth factor-A, to first-line irinotecan, 5-fluorouracil, and leucovorin (IFL) prolonged median survival in patients with metastatic colorectal cancer. We carried out a retrospective analysis of patients in the trial to evaluate whether mutation status of k-ras, b-raf, or p53 or P53 expression could predict which patients were more likely to respond to bevacizumab. METHODS Microdissected tumors from 295 patients (274 primary tumors, 21 metastases) were subject to DNA sequence analysis to identify mutations in k-ras, b-raf, and p53. Nuclear P53 expression was determined by immunohistochemistry. Hazard ratios and 95% confidence intervals (CI) for overall survival were estimated using Cox regression analysis. RESULTS In all biomarker subgroups, estimated hazard ratios for risk of death were less than 1 for bevacizumab-treated patients as compared with those for placebo-treated patients. Mutations in k-ras and/or b-raf were observed in 88 of 213 patients (41%). Hazard ratios for death among patients with tumors with wild-type k-ras/b-raf status, as compared with those of patients with mutations in one or both genes, were 0.51 (95% CI = 0.28 to 0.95) among those treated with IFL plus bevacizumab and 0.66 (95% CI = 0.37 to 1.18) among those treated with IFL plus placebo. Mutations in p53 were found in 139 of 205 patients (68%), and P53 was overexpressed in 191 of 266 patients (72%); neither p53 mutation nor P53 overexpression was statistically significantly associated with survival. CONCLUSIONS We did not find a statistically significant relationship between mutations of k-ras, b-raf, or p53 and the increase in median survival associated with the addition of bevacizumab to IFL in metastatic colorectal cancer.
Changes in postural and trunk muscles responses in patients with chronic nonspecific low back pain during sudden upper limb loading

Background: Alterations in the neuromuscular control of the spine were found in patients with chronic low back pain (CLBP). Sudden loading of the spine is assumed to be the cause of approximately 12% of lower back injuries. However, some aspects of this problem, such as alterations in the sensory–motor control of the spine, remain questionable. This study investigated postural and neuro– motor changes in trunk muscles during sudden upper limb loading in patients with CLBP. Methods: Electromyography of the erector spinae (ES) and transverses abdominis/internal oblique (TrA/IO) and external oblique (EOA) muscles were recorded in 20 patients with CLBP and 20 asymptomatic individuals with eyes open (EO) and eyes closed (EC) conditions. Moreover, measurements of the center of pressure (COP) and vertical ground reaction force (GRF) or Fz were recorded using a force plate. Data were analyzed using paired t-test and independent t-test at the significance level of 0.05. Results: In patients with CLBP, decreased electrical activity of the ES muscle was observed under both the EO and EC conditions and that of the TrA/IO muscle was observed under the EO condition (p< 0.05). Other findings included a shorter peak latency of the ES muscle in the EO condition and a greater increase in the peak latency of the ES muscle following the EC condition (p< 0.05). No significant differences were observed in COP and GRF measurements between the groups. Conclusion: Electrical muscle activity may indicate less stiffening or preparatory muscle activity in the trunk muscle of patients with CLBP. Altered latency of the muscle may lead to microtrauma of lumbar structures and CLBP.
The nature and role of social presence in audiographic, synchronous online language learning contexts

This study explores social presence (SP) and its nature and role in online language tutorials at the Open University. My research questions ask how SP is perceived to influence language learning and what factors impact on the projection of SP from the learner perspective. I also ask if these perceptions are evidenced through observed aspects of tutor and learner participation. Within the field of computer-mediated communication (CMC), SP theory has evolved from a view of SP as a product of a technological medium to an understanding of the impact of social interaction on its development and projection. Research studies in CMC highlight the importance of SP but, as yet, the links between SP and online language learning have not been fully explored. Whereas socio-cultural theory provides a framework for my understanding of the importance of social interaction in learning, I draw on the field of multimodality to gain insight into the meaning-making potential of multimodal environments. I also draw on the Community of Inquiry framework (Garrison et al., 2000) to provide both a theory and methodology for my study of SP. My principal finding is that positive SP is important in online language learning, not only to support and facilitate language interaction but also as a necessary aspect of communication in language learning. However, the generation and impact of SP are contingent upon factors related to individual learner differences and emotional responses, and to its interplay with teaching presence and ‘language learning presence’, which is a new concept. SP must always be understood in relation to the primary mediating variables of the subject area and online learning environment. The pedagogical relevance of my study is located in insights into the nature and role of SP in online language learning, derived from an integrated methodology, involving both student perspectives and my observations of online interaction.
Using means-end chains to build mobile brand communities

Brand communities are a traditional concept to enhance customer attraction, loyalty and retention (e.g. Tupperware, Apple Macintosh). Brand communities are supported through either companies or customers themselves. Companies that are able to encourage their customers to interact stimulated by the brand could position the brand value proposition of their product as a link between their customers and employ the developing brand communities for marketing purposes. To stimulate this kind of interaction, companies have increasingly used Internet functionalities in the past years. Drawing on the overwhelming penetration rate of mobile devices of over 80 percent in Europe, we propose to employ the mobile channel to support this kind of brand community building process. We derive four constitutional elements of brand communities based on existing research and develop a structured and theoretically founded four step method to analyze the potential of mobile services for specific community building purposes and compare our findings to a mini case study.
An Analytical Performance Model of Disk Arrays under Synchronous I / O Workloads

All server storage environments depend on disk arrays to sat isfy their capacity, reliability, and availability requir ements. In order to manage these storage systems efficiently, it is necessary to understand the behavior of disk arrays and predict their performance. We develop an analytical mod el that estimates mean performance measures of disk arrays under a synchronous I/O workload. Synchronous I/O re quests are generated by jobs that each block while their request is serviced. Upon I/O service completion, a job may u se other computer resources before issuing another I/O request. Our disk array model considers the effect of worklo ad sequentiality, read-ahead caching, write-back caching , and other complex optimizations incorporated into most dis k arrays. The model is validated against a mid-range disk-array for a variety of synthetic I/O workloads. The mod el is computationally simple and scales easily as the number of jobs issuing requests increases, making it potent ially useful to performance engineers.
Design and Implementation of the International Genetics and Translational Research in Transplantation Network

Background Genetic association studies of transplantation outcomes have been hampered by small samples and highly complex multifactorial phenotypes, hindering investigations of the genetic architecture of a range of comorbidities which significantly impact graft and recipient life expectancy. We describe here the rationale and design of the International Genetics & Translational Research in Transplantation Network. The network comprises 22 studies to date, including 16494 transplant recipients and 11669 donors, of whom more than 5000 are of non-European ancestry, all of whom have existing genomewide genotype data sets. Methods We describe the rich genetic and phenotypic information available in this consortium comprising heart, kidney, liver, and lung transplant cohorts. Results We demonstrate significant power in International Genetics & Translational Research in Transplantation Network to detect main effect association signals across regions such as the MHC region as well as genomewide for transplant outcomes that span all solid organs, such as graft survival, acute rejection, new onset of diabetes after transplantation, and for delayed graft function in kidney only. Conclusions This consortium is designed and statistically powered to deliver pioneering insights into the genetic architecture of transplant-related outcomes across a range of different solid-organ transplant studies. The study design allows a spectrum of analyses to be performed including recipient-only analyses, donor-recipient HLA mismatches with focus on loss-of-function variants and nonsynonymous single nucleotide polymorphisms.
Elastin in the Liver

A characteristic feature of liver cirrhosis is the accumulation of large amounts of connective tissue with the prevailing content of type I collagen. Elastin is a minor connective tissue component in normal liver but it is actively synthesized by hepatic stellate cells and portal fibroblasts in diseased liver. The accumulation of elastic fibers in later stages of liver fibrosis may contribute to the decreasing reversibility of the disease with advancing time. Elastin is formed by polymerization of tropoelastin monomers. It is an amorphous protein highly resistant to the action of proteases that forms the core of elastic fibers. Microfibrils surrounding the core are composed of fibrillins that bind a number of proteins involved in fiber formation. They include microfibril-associated glycoproteins (MAGPs), microfibrillar-associated proteins (MFAPs) and fibulins. Lysyl oxidase (LOX) and lysyl oxidase-like proteins (LOXLs) are responsible for tropoelastin cross-linking and polymerization. TGF-β complexes attached to microfibrils release this cytokine and influence the behavior of the cells in the neighborhood. The role of TGF-β as the main profibrotic cytokine in the liver is well-known and the release of the cytokines of TGF-β superfamily from their storage in elastic fibers may affect the course of fibrosis. Elastic fibers are often studied in the tissues where they provide elasticity and resilience but their role is no longer viewed as purely mechanical. Tropoelastin, elastin polymer and elastin peptides resulting from partial elastin degradation influence fibroblastic and inflammatory cells as well as angiogenesis. A similar role may be performed by elastin in the liver. This article reviews the results of the research of liver elastic fibers on the background of the present knowledge of elastin biochemistry and physiology. The regulation of liver elastin synthesis and degradation may be important for the outcome of liver fibrosis.
QUIM: a framework for quantifying usability metrics in software quality models

The paper examines current approaches to usability metrics and proposes a new approach for quantifying software quality in use, based on modelling the dynamic relationships of the attributes that affect software usability. The Quality in Use Integrated Map (QUIM) is proposed for specifying and identifying quality in use components, which brings together different factors, criteria, metrics and data defined in different human computer interface and software engineering models. The Graphical Dynamic Quality Assessment (GDQA) model is used to analyse interaction of these components into a systematic structure. The paper first introduces a new classification scheme into a graphical logic based framework using QUIM components (factors, criteria metrics and data) to assess quality in use of interactive systems. Then we illustrate how QUIM and GDQA may be used to assess software usability using subjective measures of quality characteristics as defined in ISO/IEC 9126.
Journal of Graph Algorithms and Applications a Graph Pebbling Algorithm on Weighted Graphs 222 Nándor Sieben a Graph Pebbling Algorithm on Weighted Graphs

A pebbling move on a weighted graph removes some pebbles at a ver-tex and adds one pebble at an adjacent vertex. The number of pebbles removed is the weight of the edge connecting the vertices. A vertex is reachable from a pebble distribution if it is possible to move a pebble to that vertex using pebbling moves. The pebbling number of a weighted graph is the smallest number m needed to guarantee that any vertex is reachable from any pebble distribution of m pebbles. Regular pebbling problems on unweighted graphs are special cases when the weight on every edge is 2. A regular pebbling problem often simplifies to a pebbling problem on a simpler weighted graph. We present an algorithm to find the pebbling number of weighted graphs. We use this algorithm together with graph simplifications to find the regular pebbling number of all connected graphs with at most nine vertices.
The Robustness of Authoritarianism in the Middle East: Exceptionalism in Comparative Perspective

Why have the Middle East and North Africa remained so singularly resistant to democratization? While the number of electoral democracies has nearly doubled since 1972, the number in this region has registered an absolute decline.1 Today, only two out of twenty-one countries qualify as electoral democracies, down from three observed in 1972.2 Stagnation is also evident in the guarantee of political rights and civil liberties. While the number of countries designated free by Freedom House has doubled in the Americas and in the Asia-Pacific region, increased tenfold in Africa, and risen exponentially in Central and East Europe over the past thirty years, there has been no overall improvement in the Middle East and North Africa.3 Aggregate scores in 2002 differ little from 1972. Fifteen countries are designated not free, five partly free, and only one free (see Table 1). While a few countries, notably Morocco, Jordan, Bahrain, and Yemen, have registered noteworthy progress toward political liberalization in the past decade, overall the vast majority of countries has failed to catch the wave of democratization that has swept nearly every other part of the world.
Effect of the dawn‐dusk interplanetary magnetic field By on the field‐aligned current system

[1] A constant dawn-dusk By component is set as an interplanetary magnetic field (IMF) condition in our global MHD simulations to investigate the effects of IMF By on the closure of the field-aligned current (FAC) in the magnetosphere. On the basis of the steady state magnetosphere results, we trace streamlines of FAC from the ionosphere to draw the global geometry of current streamlines in the magnetosphere. Unlike those cases in which the IMF is purely northward or southward, the introduction of the dominant IMF By significantly changes the topologies of the current streamlines. Cusp and mantle currents arise, and the symmetry of the FAC across the noon-night meridional plane breaks in the ionosphere. In addition to the self-closed currents in the Northern or Southern hemispheres, three more types of current streamlines connecting the two ionospheres are shown from the simulation results. The first current, including the cusp current, originates from the southern ionosphere and flows into the northern ionosphere. The second current, mainly the mantle current, and the tail current are connected to form a single current system, threading most of the magnetosphere along a spiral-like path and closing through the two lobes in the far magnetotail. The third current flowing out of the southern and into the northern ionosphere connects the two ionospheres by finally closing through the bow shock instead of the magnetopause. Quantitative results are presented and discussed for the four types of current streamlines and indicate that for the dominant IMF By conditions the bow shock current should be included among the magnetosphere-ionosphere current system.
Hidden Markov Models for Traffic Observation

An automated method for traffic monitoring based on statistical models of sensor behavior in combination with a Markov model of monitoring points is described. A model of normal traffic flow is automatically constructed. The model's structure and parameters are optimized using a mini-batch model-merging and parameter-updating algorithm. Incoming velocity vectors are conveyed to the model and the most probable path through the tunnel's Markov model is computed. An alarm is generated when the sensor values have a low probability under the model. The performance, strengths and weaknesses of the automated traffic flow analysis system are discussed.