Pruritus: Is there a grain of salty truth?

Hemodialysis patients characteristically suffer from a range of unpleasant symptoms. Uremic pruritus effects close to half of the chronic kidney disease population, reducing quality of life and associated with increased mortality. Its pathophysiology though is poorly understood; currently deployed therapeutic approaches are ineffective. Excessive levels of skin and soft tissue sodium accumulate in dialysis patients, producing a range of biological consequences, including inflammation. We report an index case of a hemodialysis patient with debilitating pruritus and extreme levels of tissue sodium, measured with Sodium-23 magnetic resonance imaging. Both the tissue sodium loading and pruritus responded fully to initiation of expanded hemodialysis therapy with a recently introduced medium cutoff dialysis membrane-based dialyzer.     

Is there a universal log law for turbulent wall-bounded flows?

The history and theory supporting the idea of a universal log law for turbulent wall-bounded flows are briefly reviewed. The original idea of justifying a log law from a constant Reynolds stress layer argument is found to be deficient. By contrast, it is argued that the logarithmic friction law and velocity profiles derived from matching inner and outer profiles for a pipe or channel flow are well-founded and consistent with the data. But for a boundary layer developing along a flat plate it is not, and in fact it is a power law theory that seems logically consistent. Even so, there is evidence for at least an empirical logarithmic fit to the boundary-friction data, which is indistinguishable from the power law solution. The value of kappa approximately 0.38 obtained from a logarithmic curve fit to the boundary-layer velocity data, however, does not appear to be the same as for pipe flow for which 0.43 appears to be the best estimate. Thus, the idea of a universal log law for wall-bounded flows is not supported by either the theory or the data.     

Is the proton radius a player in the redefinition of the International System of Units?

It is now recognized that the International System of Units (SI units) will be redefined in terms of fundamental constants, even if the date when this will occur is still under debate. Actually, the best estimate of fundamental constant values is given by a least-squares adjustment, carried out under the auspices of the Committee on Data for Science and Technology (CODATA) Task Group on Fundamental Constants. This adjustment provides a significant measure of the correctness and overall consistency of the basic theories and experimental methods of physics using the values of the constants obtained from widely differing experiments. The physical theories that underlie this adjustment are assumed to be valid, such as quantum electrodynamics (QED). Testing QED, one of the most precise theories is the aim of many accurate experiments. The calculations and the corresponding experiments can be carried out either on a boundless system, such as the electron magnetic moment anomaly, or on a bound system, such as atomic hydrogen. The value of fundamental constants can be deduced from the comparison of theory and experiment. For example, using QED calculations, the value of the fine structure constant given by the CODATA is mainly inferred from the measurement of the electron magnetic moment anomaly carried out by Gabrielse's group. (Hanneke et al. 2008 Phys. Rev. Lett. 100, 120801) The value of the Rydberg constant is known from two-photon spectroscopy of hydrogen combined with accurate theoretical quantities. The Rydberg constant, determined by the comparison of theory and experiment using atomic hydrogen, is known with a relative uncertainty of 6.6×10(-12). It is one of the most accurate fundamental constants to date. A careful analysis shows that knowledge of the electrical size of the proton is nowadays a limitation in this comparison. The aim of muonic hydrogen spectroscopy was to obtain an accurate value of the proton charge radius. However, the value deduced from this experiment contradicts other less accurate determinations. This problem is known as the proton radius puzzle. This new determination of the proton radius may affect the value of the Rydberg constant . This constant is related to many fundamental constants; in particular, links the two possible ways proposed for the redefinition of the kilogram, the Avogadro constant N(A) and the Planck constant h. However, the current relative uncertainty on the experimental determinations of N(A) or h is three orders of magnitude larger than the 'possible' shift of the Rydberg constant, which may be shown by the new value of the size of the proton radius determined from muonic hydrogen. The proton radius puzzle will not interfere in the redefinition of the kilogram. After a short introduction to the properties of the proton, we will describe the muonic hydrogen experiment. There is intense theoretical activity as a result of our observation. A brief summary of possible theoretical explanations at the date of writing of the paper will be given. The contribution of the proton radius puzzle to the redefinition of SI-based units will then be examined.     

Can applied science be ‘good science’? Exploring the relationship between patent citations and citation impact in nanoscience

There is a rich literature on how science and technology are related to each other. Patent citation analysis is amongst the most frequently used to tool to track the strengths of links. In this paper we explore the relationship between patent citations and citation impact in nanoscience. Our observations indicate that patent-cited papers perform better in terms of standard bibliometric indicators than comparable publications that are not linked to technology in this way. More specifically, we found that articles cited in patents are more likely to be cited also by other papers. The share of highly cited papers is the most striking result. Instead of the average of 4% of all papers, 13.8% of the papers cited once or twice in patents fall into this category and even 23.5% of the papers more frequently cited in patents receive citation rates far above the standard. Our analyses further demonstrate the presence and the relevance of bandwagon effects driving the development of science and technology.     

Is the United States losing ground in science? A global perspective on the world science system

Based on the Science Citation Index-Expanded web-version, the USA is still by far the strongest nation in terms of scientific performance. Its relative decline in percentage share of publications is largely due to the emergence of China and other Asian nations. In 2006, China has become the second largest nation in terms of the number of publications within this database. In terms of citations, the competitive advantage of the American “domestic market” is diminished, while the European Union (EU) is profiting more from the enlargement of the database over time than the USA. However, the USA is still outperforming all other countries in terms of highly cited papers and citation/publication ratios, and it is more successful than the EU in coordinating its research efforts in strategic priority areas like nanotechnology. In this field, the People’s Republic of China (PRC) has become second largest nation in both numbers of papers published and citations behind the USA.     

Is the Feminist Ethics of Care framework a useful lens for GM crop risk appraisal in the global south?

The risk assessment of genetically modified (GM) crops is assumed to be a benign regulatory tool due to its perceived objectivity and freedom from the morals and values that pervade society. Yet, against the current backdrop of ecological, social and political volatility, issues that cannot be resolved using the existing framework in South Africa are consistently emerging. This paper calls for a reformation of regulatory procedures by exploring the potential of Feminist Care Ethics to illuminate an alternative approach to the assessment of GM crops. While fresh thinking is welcome into the entangled field of biotechnology governance, there remains little understanding of how to accommodate such approaches in the context of the Global South. Twenty three interviews with participants from governmental, non-governmental and academic bodies were carried out in order to explore the potential of a Feminist Ethic of Care as an alternative framework. By examining the current appraisal procedures and tracing their evolution, problems with the current system were illuminated. To assess the suitability of the care ethic framework and ensure reflexivity, a hybrid approach to thematic analysis was applied. Using themes derived from feminist literature such as relationships, context, power, narrative and emotion, new ‘ways of seeing’ risk emerged and illuminated salient issues that are habitually ignored by the current science-based risk approach to assessment. The current approach was found to be flawed, stemming from a neoliberal, productivist perception of our socio-ecological environment. Feminist perspectives instead ask us to broaden the framing of risk, to consider different knowledges, to re-imagine ourselves as social, rather than economic beings, to tap into the capacity of socio-ecological relations and to recognize and dismantle power structures. The research concludes that although the care ethics themes offer a new approach to GM crop regulation, meaningful change will not arise from simply adding these elements to the current system. Rather, a call must be made for a re-imagining, and redesigning, both institutionally and politically-economically.     

Research or management? An investigation of the impact of leadership roles on the research performance of academic administrators

This study quantitatively investigated whether the research performance of academic administrators (leaders) was affected by their administrative services. We sampled 111 academic administrators, including 90 department deans and 21 university presidents, from 26 universities. These leaders’ research performance was determined by the number of their publications and citations in the Web of Science databases. To compare the effect on their research performance by their administrative roles, we proposed four periods: the pre-position period, the latest position period, the reference period, and the in-position period. Statistical methods were applied to compare the research performance of the sampled administrators before and after they accepted the current administrative roles. The results suggest that 80% of academic leaders’ productivity and citation have fallen by 42 and 62% averagely. The extent of such impact varied in different disciplines. Leaders’ performance in medicine fields has declined the most (60%). The impact on research productivity appeared to be stronger for administrators serving in higher-ranking universities. In addition, the research performance of both university presidents and department deans were substantially influenced by their administrative services.     

Is there a thickness effect on compressive strength of unnotched composite laminates?

The effect of laminate thickness was investigated on the compressive behavior of unidirectional and crossply composites. A recently developed compression test method for thick composites was used to test specimens from 16 to 200-plies thick. In all cases the stress-strain behavior to failure is nonlinear and failure strength is matrix dominated. Longitudinal compressive failure is triggered by matrix failure accompanied by fiber microbuckling and the compressive strength is greatly degraded by initial fiber misalignment. The longitudinal compressive strength shows a mild trend of decreasing values with increasing thickness. It can be explained that, even if such a trend is significant, increasing size would have a diminishing effect on compressive strength for initial fiber misalignments greater than 1.5 to 2°. This revised version was published online in July 2006 with corrections to the Cover Date.     

Individual latent error detection: is there a time and a place for the recall of past errors?

A task carried out in error creates a latent condition that can result in a future undesirable outcome if the error is not detected later. The paper presents a study of the relatively under-researched phenomenon of post-task latent error detection. Focusing on UK naval aircraft maintenance, it was hypothesised that time, location and systems cues influence individual latent error detection amongst naval air engineers who experience the phenomenon. The systems view of human error is combined with a multi-process approach to post-task latent error research, for which findings suggest that distributed cognition across the entire socio-technical system may be influential in post-task latent error detection. Directions for future research will be of benefit to those interested in furthering safety resilience using a systems approach to minimise the consequences arising from latent error.

Relevance to human factors/ergonomics theoryThe nature and extent of post-task latent error detection is explored using a systems approach, for which distributed cognition across the entire socio-technical system appears influential. The aim of current research is to develop interventions to further mitigate for latent errors and thus advance the systems application of ergonomics theory.     

Identifying the “Ghost City” of domain topics in a keyword semantic space combining citations

As an increasing number of scientific literature dataset are open access, more attention has gravitated to keyword analysis in many scientific fields. Traditional keyword analyses include the frequency based and the network based methods, both providing efficient mining techniques for identifying the representative keywords. The semantic meanings behind the keywords are important for understanding the research content. However, traditional keyword analysis methods pay scant attention to semantic meanings; the network based or frequency based methods as traditionally used, present limited semantic associations among the keywords. Moreover, the ways in which the semantic meanings behind the keywords are associated to the citations are not clear. Thus, we use the Google Word2Vec model to build word vectors and reduce them to a two-dimensional plane in a Voronoi diagram using the t-SNE algorithm, to link meanings with citations. The distance between semantic meanings of keywords in two-dimensional plane are similar to distances in geographical space, thus we introduce a geographic metaphor, “Ghost City” to describe the relationship between semantics and citations for hot topics that have recently become not so hot. Along with “Ghost City” zones, “Always Hot”, “Newly Emerging Hot”, and “Always Silent” areas are classified and mapped, describing the spatial heterogeneity and homogeneity of the semantic distribution of keywords cited in a domain database. Using a collection of “geographical natural hazard” literature datasets, we demonstrate that the proposed method and classification scheme can efficiently provide a unique viewpoint for interpreting the interaction between semantics and the citations, as “Ghost City”, “Always Hot”, “Newly Emerging Hot”, and “Always Silent” areas.     

Relationship among research collaboration, number of documents and number of citations: a case study in Spanish computer science production in 2000–2009

This paper analyzes the relationship among research collaboration, number of documents and number of citations of computer science research activity. It analyzes the number of documents and citations and how they vary by number of authors. They are also analyzed (according to author set cardinality) under different circumstances, that is, when documents are written in different types of collaboration, when documents are published in different document types, when documents are published in different computer science subdisciplines, and, finally, when documents are published by journals with different impact factor quartiles. To investigate the above relationships, this paper analyzes the publications listed in the Web of Science and produced by active Spanish university professors between 2000 and 2009, working in the computer science field. Analyzing all documents, we show that the highest percentage of documents are published by three authors, whereas single-authored documents account for the lowest percentage. By number of citations, there is no positive association between the author cardinality and citation impact. Statistical tests show that documents written by two authors receive more citations per document and year than documents published by more authors. In contrast, results do not show statistically significant differences between documents published by two authors and one author. The research findings suggest that international collaboration results on average in publications with higher citation rates than national and institutional collaborations. We also find differences regarding citation rates between journals and conferences, across different computer science subdisciplines and journal quartiles as expected. Finally, our impression is that the collaborative level (number of authors per document) will increase in the coming years, and documents published by three or four authors will be the trend in computer science literature.     

Review Thermal—magnetic investigation of the decomposition of copper oxalate—a precursor for catalysts

A catalyst precursor with highly developed specific surface area of 10 m²/g and a pore volume of 0.02 cm³/g is synthesized. The peculiarities of the system studied related to the structure of the copper oxalate, crystallizing as an anhydrous salt with “zeolitic type” bonded water, its content varying between 0 and 1, are pointed out. The thermal decomposition is followed by investigating the magnetic properties in situ. The results are complementary to the information obtained by DTA/TG studies. The performance of magnetic measurements and the calculation of the magnetic moment μ^eff in the range from –100 to 300^∘C allow a conclusion to be drawn concerning the coordination of the Cu(II) ions and the change in the oxidation state. In the starting oxalate, Cu(II) is in a tetrahedral-like coordination, which is a result of the strong tetragonal deformation of the octahedral field and of the stronger tendency of the oxalate ion to rotate around the C–C bond axis. The dehydration process does not affect the XRD results, but changes the temperature dependence of μ^eff due to the change in the Cu(II) coordination. The μ^eff values during the decomposition process suggest that the proportion Cu(II)-Cu(I) could be varied in the final product by varying the temperature range. By isothermal annealing at 300^∘C for 1 h, an oxide product containing Cu(II)-Cu(I) is synthesized and characterized. The solid phase products corresponding to the separate parts of the DTA/TG curves are: [Cu] → Cu + Cu²O (185–300^∘C), 0.5Cu²O + 2CuO (300–345^∘C), 3CuO (345–400^∘C).     

Do cover papers get better citations and usage counts? An analysis of 42 journals in cell biology

Scientometrics - Research on the impact of and attention given to journal covers is a crucial research topic in academia. This study investigated whether a paper featured on the cover of a journal...     

An investigation of the nozzle’s atomization dust suppression rules in a fully-mechanized excavation face based on the airflow-droplet-dust three-phase coupling model

In order to suppress the diffusion of high concentrations of dust towards the operating area in a fully-mechanized excavation face effectively, this study constructed a mathematical model that describes the interactions among droplets, dust and airflows, and then validated the accuracy of the established model. Finally, under single-forced ventilation conditions, the dust suppression rules when different nozzles were used at different spraying pressures were investigated in detail. The results reveal that when different spraying schemes were used, the dust mass distributions in different regions along the tunnel were basically the same; they all first decreased, then increased and finally decreased. At a spraying pressure of 2–8?MPa, the spraying pressure and dust suppression efficiency followed a logarithmic function; however, with an increase in the spraying pressure, the dust suppression efficiency increased gradually at a declining rate. Under a spraying pressure of 8?MPa, the dust clusters in which the dust concentration exceeded 110?mg/m³ in the fully-mechanized excavation face were reduced significantly. Out of all the spraying schemes, the one using K2.0 nozzles at a spraying pressure of 8?MPa achieved the most favorable dust suppression performance, and the dust suppression efficiency in a fully-mechanized excavation face was as high as 86.1%; meanwhile, the proportion of respirable dust with a diameter smaller than 7?μm increased gradually from 16% to 27%.     

Is the Tendency to Variation a Chief Cause of Progress?

This paper briefly reviews the sources of the diversity of innovativeactivity within industries, and interprets the literature tosuggest that there are three ways in which such diversity maystimulate technological progress, including a selection effect,a breadth effect and a complementarity effect. Using industry-leveldata from the Yale survey administered in the 1980s, the paperpresents preliminary empirical results on the relationship betweenthe diversity of R&D activities within industries and theirrate of technical advance. This exploratory exercise finds that,controlling for industry R&D intensity, greater diversityin innovative activity is associated with a more rapid paceof technological change. Policy implications are considered.