Exploratory analysis of text duplication in peer-review reveals peer-review fraud and paper mills

Scientometrics - Comments received from referees during peer-review were analysed to determine the rates of duplication and partial duplication. It is very unusual for 2 different referees to...     

Scientometric indicators: peer-review,bibliometric methods and conflict of interests

The paper discusses the role of scientometric indicators in peer-review selection of research project proposals. An ex post facto evaluation was made of three calls for research project proposals in Slovenia: 2003 with a peer review system designed in a way that conflict of interest was not avoided effectively, 2005 with a sound international peer-review system with minimized conflict of interest influence but a limited number of reviewers, and 2008 with a combination of scientometric indicators and a sound international peer review with minimized conflict of interest influence. The hypothesis was that the three different peer review systems would have different correlations with the same set of scientometric indicators. In the last two decision-making systems (2005 and 2008) where conflict of interest was effectively avoided, we have a high percentage (65%) of projects that would have been selected in the call irrespective of the method (peer review or bibliometrics solely). In contrast, in the 2003 call there is a significantly smaller percentage (49%) of projects that would have been selected in the call irrespective of the method (peer review or bibliometrics solely). It was shown that while scientometric indicators can hardly replace the peer-review system as the ultimate decision-making and support system, they can reveal its weaknesses on one hand and on the other can verify peer-review scores and minimize conflict of interest if necessary.     

Persistent Themes

Abstract

The Department of Photographs was founded in mid-1984 with the acquisition of several major collections, including those of Samuel Wagstaff, Arnold Crane, Bruno Bischofberger, William I. Homer, Georg Heusch, and Volker Kahmen, and complementary parts of other collections, including those of André. Jammes and Daniel Wolf. Since then more than 7,500 individual images have been purchased, and thousands more have been added by gift to the original acquisition of approximately 45,000 images. Some of the most important of these recent acquisitions have been displayed in the 16 exhibitions that have been held since 1986.     

Persistent currents in superfluid3He

Measurements are reported of persistent currents in superfluid³He-B and³He-A. An ac gyroscope filled with 20 µm powder and mounted into a rotating nuclear refrigerator was employed. In³He-B, undiminished circulation was observed for 48 h; this implies an effective viscosity at least 12 orders of magnitude lower than in the normal fluid at the same temperature. AtP<15 bar, the observed critical velocity is independent of temperature but it is a weak function of pressure;v _c varies between 4 and 6 mm/sec. The response to rotation is hysteretic, with elastic potential flow at slow rotation and irreversible vortex flow at higher angular velocities. The persistent angular momentumL is reversible when thermally cycled in the B phase, and proportional to the superfluid fraction _s /. Above 15 bar the B phase splits into separate regions with different critical velocities. The measuredv _c in the phase existing only at high pressures is dependent on magnetic field; for example, at 23.0 bar,v _c (H=0) =5 mm/sec, butv _c (H=40 G) =15 mm/sec. In the low pressure phase,v _c is insensitive to a change in the magnetic field. The phase transition is of first order; the latent heatQ _G (1 µJ/mole) depends on the maximum angular velocity at which the cryostat was rotated. The transition is proposed to occur in the core structure of pinned quantized vortices sustaining persistent currents. In³He-A, currents could not be found to persist on an observable level. Direct measurements ofL atH=0 and atH=40 G, and repeated thermal cycling, showed that either the current decays rapidly orv _c <0.5 mm/sec.     

Persistent pollutants emission abatement in waste-to-energy systems

The paper is focused on analyzing methods, which enable a substantial reduction of persistent organic pollutants (POP) emissions to meet the environmental limits. Technologies based on adsorption of harmful compounds using activated carbon, technologies DeNOx/DeDiox as well as technology of catalytic filtration using a special material REMEDIA D/F are considered and compared. The latter technology consists in using a bag-house with bags manufactured from a special material (two layers—membrane from expanded PTFE and felt with bound in catalyst) called REMEDIA, which has successfully been used for the removal of PCDD/F during recent period. An optimum design is based on the computational support concerning the bag-house. It is illustrated through an industrial application of the municipal solid waste (MSW) incinerator with capacity of 15 t/h (96.000 t/year) of waste treated which is operated as a waste-to-energy system. Based on the experience from operating this incineration plant it has been proved that even after more than 3 years operation the activity of filtration material was not decreased and efficiency of dioxins removal from flue gas ranges from 97 to 99%. These facts come from complex measurements where concentration of PCDD/F toxic congeners in both flue gas and separated flying ash was measured. We arrived at confirming expected assumptions that various congeners are not decomposed uniformly in the dioxin filter and the stage of their decomposition depends on their representation in the gas phase. It is strongly influenced by their molecular weight. Their results and experience contribute to further improving the system.     

Persistent current states in rotating superfluid helium

Persistent current states in superfluid helium contained in a rotating superleak are studied for various velocities and initial conditions. The change in the superfluid component velocity as the normal component velocity changes is interpreted in terms of a circulation-free potential flow and the entrance of vortices. The appearance of vortices of opposite sign to that of preexisting ones in the superleak is discussed and this is related to the history-dependent nature of persistent currents. An analogy between a superfluid helium system such as ours and a highly irreversible type-II superconductor is made.     

Persistent Currents in Toroidal Single-wall Carbon Nanotubes

Carbonnan.t.b.,l1]aswelLdefinedquasi-one-dimensi0nalmaterialswithpotentialapplicationsinnanostructureelectronicshaveattractedsignificanti.t...,t[2~4].Astraightsingle-wallcarbonnanotube(SSWNT)canbeimaginedbyr0llingupasinglegraphitesheetwithtwoequivalentsitescoincidence.Thetubeaxisxisverticaltothevect0rCwhichc0n-nectsthetwoequivalentsites(Fig.l).Ifthetubeaxisisneitherverticalnorparalleltoanycarb0n-carbon(C-C)bond,thetubeischiralandahelicityde-n0tedby(m,n)(m>n>O)exists[2j.Otherwisethetubeisa…     

Recent Advances of Persistent Luminescence Nanoparticles in Bioapplications

Persistent luminescence phosphors are a novel group of promising luminescent materials with afterglow properties after the stoppage of excitation.In the past decade,persistent luminescence nanoparticles(PLNPs)with intriguing optical properties have attracted a wide range of attention in various areas.Especially in recent years,the development and applications in biomedical fields have been widely explored.Owing to the efficient elimination of the autofluorescence interferences from biotissues and the ultra-long near-infrared afterglow emission,many researches have focused on the manipulation of PLNPs in biosensing,cell tracking,bioimaging and cancer therapy.These achievements stimulated the growing interest in designing new types of PLNPs with desired superior characteristics and multiple functions.In this review,we summarize the works on synthesis methods,bioapplications,biomembrane modification and biosafety of PLNPs and highlight the recent advances in biosensing,imaging and imaging-guided therapy.We further discuss the new types of PLNPs as a newly emerged class of functional biomaterials for multiple applications.Finally,the remaining problems and challenges are discussed with suggestions and prospects for potential future directions in the biomedical applications.     

Persistent Currents Versus Phase Breaking in Mesoscopic Metallic Samples

Persistent currents in mesoscopic normal metal rings represent, even a decade after their first experimental observation, a challenge to both, theorists and experimentalists. After giving a brief review of the existing - experimental and theoretical - results, we concentrate on the (propsed) relationship of the size of the persistent current to the phase breaking rate. In particular, we consider effects induced by noise, scattering at two-level systems, and magnetic impurities.     

National peer-review research assessment exercises for the hard sciences can be a complete waste of money: the Italian case

There has been ample demonstration that bibliometrics is superior to peer-review for national research assessment exercises in the hard sciences. In this paper we examine the Italian case, taking the 2001–2003 university performance rankings list based on bibliometrics as benchmark. We compare the accuracy of the first national evaluation exercise, conducted entirely by peer-review, to other rankings lists prepared at zero cost, based on indicators indirectly linked to performance or available on the Internet. The results show that, for the hard sciences, the costs of conducting the Italian evaluation of research institutions could have been completely avoided.     

Persistent Precessing Texture-Trapped Domains in Low Temperature Superfluid 3He

It has recently been discovered that at temperatures below about 0.2T _C in superfluid ³ He-B, pulsed NMR excitation can generate a new coherently precessing spin state which can have a lifetime of tens of seconds. The free induction decay signal from this state has been called the persistent induction signal (PIS). The earlier observations of the PIS have found it to be highly irreproducible indicating a strong connection with the magnetic texture. Here we describe measurements of the PIS within an experimental cell which was designed to fix the textural configuration of the superfluid. The resulting PIS signals are now far more reproducible allowing a more systematic study of the behaviour which we present here. Furthermore in the latest cell the decay of this signal has been observed to last for up to 4 minutes at the lowest temperatures. While the precessing state is readily accessible to observation, at these temperatures it is a very delicate object and we can immediately see the influence of background radiation on the time evolution of the decay.     

Kondo Impurity in a Mesoscopic Ring: Charge Persistent Current

We study the influence of a magnetic impurity or ultrasmallquantum dot on the charge persistent current of a mesoscopicring. The system consists of electrons in a one-dimensionalring threaded by spin-dependent Aharonov–Bohm/Casher fluxes,coupled via an antiferromagnetic exchange interaction to alocalized electron. By passing to a basis of electron stateswith definite parities, the problem is mapped onto a Kondomodel for the even-parity channel plus free electrons in theodd-parity channel. The twisted boundary conditionsrepresenting the fluxes couple states of opposite parityunless the twist angles satisfy =f,where f are integers, with spin index=, . For these special values of, the model is solved exactly by a Bethe ansatz.Special cases are investigated in detail. In particular weshow that the charge stiffness in the case= is insensitive to the presenceof the magnetic impurity/quantum dot.     

Persistent Currents in a Bose-Einstein Condensate in the Presence of Disorder

We examine bosonic atoms that are confined in a toroidal, quasi-one-dimensional trap, subjected to a random potential. The resulting inhomogeneous atomic density is smoothened for sufficiently strong, repulsive interatomic interactions. Statistical analysis of our simulations show that the gas supports persistent currents, which become more fragile due to the disorder.      

Persistent currents and critical velocities in3He-4He mixtures

Using the method of Doppler-shifted fourth sound, we have investigated the angular velocity _c1 for the onset of vorticity, the saturated critical velocity, and the dependence of _s/ onv _n –v _s for⁴He in three different pore sizes and for three different mixtures of ³ He- ⁴ Hein one of the powders used. These are the first measurements of critical velocities in ³ He- ⁴ He mixtures. We observe only a weak dependence of _c1on the pore size and within the limits of the experiment no dependence on concentrationX up toX=0.11. We find, however, that the maximumv _n –v _s attainable increases as the concentration of ³ He increases forX0.17. The observed dependence of the superfluid density onv _n –v _s is approximately two orders of magnitude stronger than predicted.