Trend and impact of international collaboration in clinical medicine papers published in Malaysia

Research collaboration is the way forward in order to improve quality and impact of its research findings. International research collaboration has resulted in international co-authorship in scientific communications and publications. This study highlights the collaborating research and authorship trend in clinical medicine in Malaysia from 2001 to 2010. Malaysian-based author affiliation in the Web of Science (Science Citation Index Expanded) and clinical medicine journals (n = 999) and articles (n = 3951) as of 30th Oct 2011 were downloaded. Types of document analyzed were articles and reviews, and impact factors (IF) in the 2010 Journal Citation Report Science Edition were taken to access the quality of the articles. The number of publications in clinical medicine increased from 4.5 % (n = 178) in 2001 to 23.9 % (n = 944) in 2010. The top three contributors in the subject categories are Pharmacology and Pharmacy (13.9 %), General and Internal Medicine (13.6 %) and Tropical Medicine (7.3 %). By journal tier system: Tier 1 (18.7 %, n = 738), Tier 2 (22.5 %, n = 888), Tier 3 (29.6 %, n = 1170), Tier 4 (27.2 %, n = 1074), and journals without IF (2.1 %, n = 81). University of Malaya was the most productive. Local collaborators accounted for 60.3 % and international collaborations 39.7 %. Articles with international collaborations appeared in journals with higher journal IFs than those without international collaboration. They were also cited more significantly than articles without international collaborations. Citations, impact factor and journal tiers were significantly associated with international collaboration in Malaysia’s clinical medicine publications. Malaysia has achieved a significant number of ISI publications in clinical medicine participation in international collaboration.     

Evolution of texture and development of ∑3 n grain clusters in 316 austenitic stainless steel during thermal mechanical processing

A type 316 austenitic stainless steel sheet with various texture components along its thickness was slightly cold-rolled and then sequentially annealed at 1000 °C for 80 and 150 min. The evolution of texture and the development of grain clusters in which the grains are interfaced by ∑3 ⁿ (n = 0, 1, 2, 3…) boundaries (∑3 ⁿ GC) were studied by electron backscatter diffraction (EBSD). The results show that the texture difference along the thickness was minimized, and large (greater than 400 μ) ∑3 ⁿ GCs developed after cold rolling and annealing. In situ EBSD examination revealed that each ∑3 ⁿ GC was developed by the oriented-growth (OG) of brass ({110} $ \langle 112\rangle $ ), copper ({112} $ \langle 111\rangle $ ) and C1 ({114} $ \langle 041\rangle $ ) orientations (including their geometric variants). These orientations are intrinsically related to ∑3 ⁿ misorientations. The abutting ∑3 ⁿ GCs with grains of nearly the same or ∑3 ⁿ -related orientations usually merged into a larger ∑3 ⁿ GC or resulted in an effective disruption of the connectivity of the random high angle grain boundary network.     

A surname-based patent-related indicator: the contribution of Jewish inventors to US patents

It was found that the surname-based representation of Jewish authors in the top US biomedical journals corresponds to the representation of Jewish Nobel Laureates in Medicine among US laureates: Both of them are almost equally disproportionately high, with the ratio of actual to expected number close to 20 (Kissin, Scientometrics 89:273–280, 2011). The main aim of this study was to determine whether the contribution of Jewish inventors is also disproportionately high. The number of patents (US Patent and Trademark Office database) per thousand persons with the same surname (2000 Census) was determined (index P). Index P was compared with index A, which represents the number of the articles in the top US biomedical journals, and index G, which is based on the representation of a surname in the Google’s option “Discussions”, reflecting a combination of various business and leisure activities (designed as a negative control). The collective contributions of the 96 Jewish surname groups for each of the above indices were calculated. The ratio of actual to expected number of US patents was found to be disproportionately high—6.1 (p < 0.0001). At the same time, this disproportionality was four-fold lower than that related to biomedical articles (ratio of 6.1 vs. 23.3, p < 0.0001). There was some degree of correlation between index P and index A (r = 0.407, p < 0.0001), but no significant correlation was found between index P and index G. The role of various factors in the observed disproportionalities is discussed. The greater degree of disproportionality with biomedical research articles might be a consequence of traditional Jewish inclination towards occupations in medicine.     

Rotation statistics of fibers in wall shear turbulence

In this paper, the rotation of rigid fibers is investigated for the reference case of turbulent channel flow. The aim of the study is to examine the effect of local shear and turbulence anisotropy on the rotational dynamics of fibers with different elongation and inertia. To this aim, statistics of the fiber angular velocity, Ω, are extracted from direct numerical simulation of turbulence at shear Reynolds number Re _τ = 150 coupled with Lagrangian tracking of prolate ellipsoidal fibers with Stokes number, St, ranging from 3 to 100 and aspect ratio, λ, ranging from 1 to 50. Accordingly, the fiber-to-fluid density ratio ranges from ${S \simeq 7}$ S ? 7 (for St = 1, λ = 50) to ${S \simeq 3, 470}$ S ? 3 , 470 (for St = 100, λ = 1). Statistics are compared one to one with those obtained for spherical particles to highlight effects due to elongation. Results for mean and fluctuating angular velocities show that elongation is important for fibers with small inertia (St ≤  5 in the present flow-fiber combination). For fibers with larger inertia, elongation has an impact on fiber rotation only in the streamwise and wall-normal directions, where mean values of Ω are zero. It is also shown that, in the center of the channel, the Lagrangian autocorrelation coefficients of Ω and corresponding rotational turbulent diffusivities match the exponential behavior predicted by the theory of homogeneous dispersion. In this region of the channel, the probability density function of fiber angular velocities is generally close to Gaussian, indicating that particle rotation away from solid walls can be modeled as a diffusion process of the Ornstein–Uhlenbeck type at stationary state. In the strong shear region (comprised within a distance of 50 viscous units from the wall in the present simulations), fiber anisotropy adds to flow anisotropy to induce strong deviations on fiber rotational dynamics with respect to spherical particles. The database produced in this study is available to all interested users at https://www.fp1005.cism.it.     

A polynomial parametrization of torus knots

For every odd integer N we give explicit construction of a polynomial curve ${\mathcal C(t)=(x(t),y(t))}$ , where ${{\rm deg}\, x=3, {\rm deg}\, y=N + 1 + 2[\frac{N}{4}]}$ that has exactly N crossing points ${\mathcal C(t_i)=\mathcal C(s_i)}$ whose parameters satisfy s ₁ < ? < s _N < t ₁ < ? < t _N . Our proof makes use of the theory of Stieltjes series and Padé approximants. This allows us an explicit polynomial parametrization of the torus knot K _2,2n+1 with degree (3, 3n + 1, 3n + 2).     

Temperature-dependent electrical properties of 0.5Pb(Ni1/3Nb2/3)O3–(0.5 − x)PbTiO3–xPbZrO3 piezoceramics near the morphotropic phase boundary

0.5Pb(Ni_1/3Nb_2/3)O₃–(0.5 ? x)PbTiO₃–xPbZrO₃ (x = 0.10–0.20) polycrystalline ceramics were fabricated by solid-state reaction method. The phase structures, microstructure and temperature dependence of the electrical properties were investigated in detail. Both X-ray diffraction and Raman spectroscopy results indicated that the morphotropic phase boundary (MPB) separating tetragonal from rhombohedral phases located around the region with x = 0.14–0.16. Well-saturated ferroelectric P–E loops were obtained for all compositions and the compositions near MPB possessed the relative large remnant polarization P _r  ~ 24 μC/cm² and low coercive field E _c  ~ 5 kV/cm. High performance of electric-induced-strain property with $ d_{33}^{*} $ (S _max /E _max ) up to 1,140 pm/V could be achieved in the composition with x = 0.15. When the content of PbZrO₃ was 14 mol%, the ceramics showed slightly lowered piezoelectric coefficient $ d_{33}^{*} $ of 898 pm/V. But excellent temperature stability of piezoelectric property was exhibited that the $ d_{33}^{*} $ changed <10 % when the temperature increased from room temperature to 120 °C. The piezoelectric property of this solid solution makes it promising for application in multilayer piezoactuators.     

Probabilistic assessment of torsion in concrete beams externally strengthened with CFRP composites

This paper illustrates an analytical probabilistic study of concrete beams subjected to torsion that are strengthened with carbon fiber reinforced polymer (CFRP). Hii and Al-Mahaidi’s method is one of the best analytical models for evaluating the torsional capacity of CFRP strengthened reinforced concrete beams. The first-order reliability method is carried out to probabilistically assess the capacity of CFRP-strengthened beams. For this aim, the statistical characteristics of design variables and model errors have been considered, followed by the determination of the average reliability indexes of the strengthened beams. The effect of each design variable on the average reliability is also determined. The assessment shows that the Hii and Al-Mahaidi’s analytical model is unconservative. In order to correct the situation, a more relaxed set of resistance factors for use in a load and resistance factor design format are needed. These are then determined for two target reliability levels of $ \beta_{\text T} $  = 3.0 and $ \beta_{\text T} $  = 3.5. It is found that factors of 0.9200 and 0.8225 are needed for target reliability levels, $ \beta_{\text T} $  = 3.0 and $ \beta_{\text T} $  = 3.5, respectively. Values of 0.9 and 0.8 are suggested for use in real practice depending on the target reliability sought.     

Higgs Bosons in Particle Physics and in Condensed Matter

Higgs bosons—the amplitude modes—have been experimentally investigated in condensed matter for many years. An example is superfluid ³He-B, where the broken symmetry leads to 4 Goldstone modes and at least 14 Higgs modes, which are characterized by angular momentum quantum number J and parity (Zeeman splitting of Higgs modes with J=2⁺ and J=2^? in magnetic field has been observed in 80’s). Based on the relation $E_{J+}^{2}+E_{J-}^{2}=4\varDelta^{2}$ for the energy spectrum of these modes, Yoichiro Nambu proposed the general sum rule, which relates masses of Higgs bosons and masses of fermions. If this rule is applicable to Standard Model, one may expect that the observed Higgs boson with mass M _H1=125 GeV has a Nambu partner—the second Higgs boson with mass M _H2=325 GeV. Together they satisfy the Nambu relation $M_{\mathrm{H}1}^{2} + M_{\mathrm{H}2}^{2} = 4 M_{\mathrm{top}}^{2}$ , where M _top is the top quark mass. Also the properties of the Higgs modes in superfluid ³He-A, where the symmetry breaking is similar to that of the Standard Model, suggest the possible existence of two electrically charged Higgs particles with masses M _H+=M _H?～245 GeV, which together obey the Nambu rule $M_{\mathrm{H}+}^{2} + M_{\mathrm{H}-}^{2} = 4 M_{\mathrm{top}}^{2}$ . A certain excess of events at 325 GeV and at 245 GeV has been reported in 2011, though not confirmed in 2012 experiments. Besides, we consider the particular relativistic model of top—quark condensation that suggests the possibility that two twice degenerated Higgs bosons contribute to the Nambu sum rule. This gives the mass around 210 GeV for the Nambu partner of the 125 GeV Higgs boson. We also discuss the other possible lessons from the condensed matter to Standard Model, such as hidden symmetry, where light Higgs emerges as quasi Nambu-Goldstone mode, and the role of broken time reversal symmetry.     

Correlation Between Band Structure and Magneto- Transport Properties in HgTe/CdTe Two-Dimensional Far-Infrared Detector Superlattice

Theoretical calculations of the electronic properties of n-type HgTe/CdTe superlattices (SLs) have provided an agreement with the experimental data on the magneto-transport behaviour. We have measured the conductivity, Hall mobility, Seebeck and Shubnikov-de Haas effects and angular dependence of the magneto-resistance. Our sample, grown by MBE, had a period d=d ₁+d ₂ (124 layers) of $d_{1}=8.6~\mathrm{nm}~\mathrm{(HgTe)} /d_{2}=3.2~\mathrm{nm}~\mathrm{(CdTe)}$ . Calculations of the spectras of energy E(d ₂), E(k _z ) and E(k _p ), respectively, in the direction of growth and in plane of the superlattice; were performed in the envelope function formalism. The energy E(d ₂,Γ,4.2 K), shown that when d ₂ increase the gap E _g decrease to zero at the transition semiconductor to semimetal conductivity behaviour and become negative accusing a semimetallic conduction. At 4.2 K, the sample exhibits n type conductivity, confirmed by Hall and Seebeck effects, with a Hall mobility of $2.5 \times 10^{5}~\mathrm{cm}^{2}/ \mathrm{V\,s}$ . This allowed us to observe the Shubnikov-de Haas effect with n=3.20×10¹² cm^?2. Using the calculated effective mass ( $m^{*}_{E1}(E_{F}) = 0.05 m_{0}$ ) of the degenerated electrons gas, the Fermi energy (2D) was E _F =88 meV in agreement with 91 meV of thermoelectric power α. In intrinsic regime, α～T ^?3/2 and R _H T ^3/2 indicates a gap E _g =E ₁?HH ₁=101 meV in agreement with calculated E _g (Γ,300 K)=105 meV. The formalism used here predicts that the system is semiconductor for d ₁/d ₂=2.69 and d ₂<100 nm. Here, d ₂=3.2 nm and E _g (Γ,4.2 K)=48 meV so this sample is a two-dimensional modulated nano-semiconductor and far-infrared detector (12 μm<λ _c <28 μm).     

({p, \rho,T, x}) Properties of \text{ CO}_{2}/Propane Binary Mixtures at 280 K to 440 K and 3 MPa to 200 MPa

The (p, \(\rho \) , T, x) properties of binary mixtures of CO \(_{2}\) (volume fraction purity 0.99999) and propane (mole fraction purity 0.9999) ( \(x_{1}\) CO \(_{2}+x_{2}\) propane; \(x_{1} = 0.1744\) , 0.3863, 0.5837, and 0.7732) were measured in the compressed liquid phase using a metal-bellows variable volumometer. Measurements were conducted from 280 K to 440 K and 3 MPa to 200 MPa. The expanded uncertainties ( \(k = 2\) ) were estimated to be temperature, \(<\) 3 mK; pressure, 1.5 kPa ( \(p\le 7\)  MPa), 0.06 % (7 MPa \(< p\le 50\)  MPa), 0.1 % (50 MPa \(< p\le 150\)  MPa), 0.2 % ( \(p> 150\)  MPa); density, 0.10 %; and composition, \(4.4\times 10^{-4}\) . At \(p >100\)  MPa and 280 K or 440 K, the uncertainties in density measurements increase to 0.14 % and 0.22 %, respectively. The data were compared with available equations of state. The excess molar volumes, \(v_\mathrm{m}^\mathrm{E}\) , of the mixtures were calculated and plotted as a function of temperature and pressure.     

Inventions shaping technological trajectories: do existing patent indicators provide a comprehensive picture?

Since Schumpeter’s (The theory of economic development, 1934) seminal work on economic development, innovation is considered as one of the main drivers of firm performance and economic growth. At the same time, technological innovations vary considerably in terms of impact with only a minority of new inventions contributing significantly to technological progress and economic growth. More recently a number of indicators derived from patent documents have been advanced to capture the nature and impact of technological inventions. In this paper, we compare and validate these indicators within the field of biotechnology. An extensive analysis of the recent history of biotechnology allows us to identify the most important inventions (n = 214) that shaped the field of biotechnology in the time period 1976–2001. A considerable number of these inventions have been patented between 1976 and 2001 (n = 117, 55 %). For all USPTO biotech patents filed between 1976 and 2001 (n = 84,119), relevant indicators have been calculated. In a subsequent step, we assess which indicators allow us to distinguish between the most important patented inventions and their less influential counterparts by means of logistic regression models. Our findings show that the use of multiple, complementary indicators provides the most comprehensive picture. In addition, it is clear that ex-post indicators reflecting impact and value outperform ex-ante indicators reflecting the nature and novelty of the invention in terms of precision and recall.     

Measurement of the (p, \rho,T) Properties for Pure Hydrocarbons at Temperatures up to 600 K and Pressures up to 200 MPa

The data available for the thermodynamic properties of propane, \(n\) -butane, and isobutane at temperatures above 440 K are outdated and show significant discrepancies with each other. The ambiguity associated with these data could be limiting to the development of any understanding related to the effects of mixing of these substances with other materials such as \(\text{ CO}_{2}\) , ammonia, and non-flammable or lower-flammable HFC refrigerants. In this study, the (p, \(\rho \) , T) properties of propane, \(n\) -butane, and isobutane were measured at temperatures ranging from (360 to 600) K and pressures ranging from (50 to 200) MPa. Precise measurements were carried out using a metal-bellows variable volumometer with a thermostatted air bath. The expanded uncertainties \((k = 2)\) in the temperature, pressure, and density measurements were estimated to be \(<\) 5 mK, 0.02 MPa, and 0.88 kg  \(\cdot \)  m \(^{-3}\) ( \(T\le 423\)  K, \(p<100\)  MPa), 0.76 kg  \(\cdot \)   \(\text{ m}^{-3}\) ( \(T\le 423\)  K, \(p\ge 100\)  MPa), 0.76 kg  \(\cdot \)   \(\text{ m}^{-3}\) ( \(T>423\)  K, \(p < 100\)  MPa), and 2.94 kg  \(\cdot \)   \(\text{ m}^{-3}\) ( \(T>423\)  K, \(p \ge 100\)  MPa), respectively. The data obtained throughout this study were systematically compared with the calculated values derived from the available equations of state. These models agree well with the measured data at higher temperatures up to 600 K, demonstrating their suitability for an effective and precise examination of the mixing effects of potential alternative mixtures.     

The effect of characteristics of title on citation rates of articles

This study aimed to assess the association between some features of articles title and number of citations in a volume of Addictive Behavior journal. All research articles published in the volume number 32 (2007) in the Addictive Behaviors journal (n = 302) were analyzed by two independent authors. For each article, the following information has been extracted: number of citations up to June 2013 in the Scopus citation database, type of and characteristics of titles, having different words in the keywords, reference to place and presence of an acronym. The summary statistics showed that mean number of citation was 16.36 ± 19.55 times. Articles with combinational title (use of a hyphen or a colon separating different ideas within a sentence) and articles with different words in the keywords (at least two different keywords) had higher number of citations. The number of citations was not correlated with the number of words in the title (r = 0.05, P = 0.325). Our results suggested that some features in the paper such as type of the title and articles with keywords different from words included in the title can help to predict the number of citation counts. These findings can be used by authors and reviewers in order to maximize the impact of articles. The length of title is not associated with citation counts. Therefore, the guide for authors of journals can be more flexible regarding the length of the title.     

Investigation of the lithium-rich boundary of the Li1+x Mn2−x O4 cubic spinel phase in air

Several compositions of the cubic spinel Li_1+x Mn_2?x O_4?δ phase in the lithium–manganese–oxygen (Li–Mn–O) system were synthesized at 700, 750, and 800 °C in air ( $ p_{{{\text{O}}_{2} }} $  = 0.2 atm) to investigate the Li-rich boundary of the cubic spinel phase at these temperatures. The lattice parameters of the several compositions were determined by Rietveld analysis of the measured X-ray patterns, and the Li and Mn contents of the samples were measured using inductively coupled plasma with optical emission spectroscopy (ICP-OES). A Vegard-like dependence of the measured lattice parameter of the cubic spinel phase with Li to Mn ratio exists in the homogeneity range of the cubic spinel. This dependence could be used to derive the boundary of the single phase cubic spinel field in the Li–Mn–O system at 700 and 750 °C at $ p_{{{\text{O}}_{2} }} $  = 0.2 atm and to estimate the Li-rich boundary at 800 °C. The results of the present study are compared with two other experimental studies on the homogeneity range of the cubic spinel phase in an attempt to resolve the contradiction between these two studies.     

Dislocation structures in a { \bar{1} 104}/��11 \bar{2} 0�� low-angle tilt grain boundary of alumina (��-Al2O3)

An alumina (??-Al₂O₃) bicrystal with a ( $ \bar{1} $ 104)/[11 $ \bar{2} $ 0] 2^o low-angle tilt grain boundary was fabricated by diffusion bonding at 1500 °C in air, and the grain boundary was observed by transmission electron microscopy (TEM). High-resolution TEM observations revealed that the grain boundary consists of at least two kinds of dislocations. One is a perfect dislocation which has a Burgers vector of 1/3[ $ \bar{1} $ 2 $ \bar{1} $ 0]. The other is dissociated into two partial dislocations with a stacking fault on the (0001) plane, and each partial dislocation has a 1/6[ $ \bar{1} $ 101] edge component. It is suggested from structural considerations that the dissociated-dislocation pair originates from a b = 1/3[02 $ \bar{2} $ 1] perfect dislocation (i.e., 1/3[02 $ \bar{2} $ 1] ?? 1/6[02 $ \bar{2} $ 1] + 1/6[02 $ \bar{2} $ 1]). This dissociation produces a stacking fault in the anion sublattice. The stacking fault energy is estimated to be roughly 1.3 Jm^?2 based on the elastic theory. The authors discuss the dislocation structures and the stacking fault formed on the (0001) plane in detail.     

Spin-Polarized Calculations of Magnetic and Thermodynamic Properties of the Full-Heusler \mathrm{{Co}}_{2}MnZ (Z = Al, Ga)

The purpose of this study is to further understanding of the structural, electronic, magnetic, and thermal properties of the full-Heusler compounds, ${\mathrm{{Co}}}_{2}$ Co 2 MnAl and ${\mathrm{{Co}}}_{2}$ Co 2 MnGa, using density functional theory. Electronic structure calculations will be performed using the full potential linear augmented plane wave. The electronic structures and magnetic properties of ${\mathrm{{Co}}}_{2}$ Co 2 MnZ (Z = Al, Ga) compounds with ${\mathrm{L}}2_{1 }$ L 2 1 structure are studied. It is shown that the calculated lattice constants and spin magnetic moments are in good agreement with experimental values using the general gradient approximation method. Thermal effects on some macroscopic properties of ${\mathrm{{Co}}}_{2}$ Co 2 MnZ (Z = Al, Ga) compounds are predicted using the quasi-harmonic Debye model, in which the lattice vibrations are taken into account. The variations of the lattice constant, volume expansion coefficient, heat capacities, and Debye temperature with pressure and temperature in the ranges of 0 GPa to 18 GPa and 0 K to700 K have been obtained.     

Toward a Detector/Readout Architecture for the Background-Limited Far-IR/Submm Spectrograph (BLISS)

We have built and tested 32-element linear arrays of absorber-coupled transition-edge sensors (TESs) read out with a time-division SQUID multiplexer. This detector/readout architecture is designed for the background-limited far-IR/submm spectrograph (BLISS) which is a broadband (35–433  \(\upmu \) m), grating spectrometer consisting of six wavebands each with a modest resolution of R \(\sim \) 700. Since BLISS requires the effective noise equivalent power (NEP) of the TESs to equal 1  \(\times \)  10 \(^{-19}\)  W/Hz \(^{1/2}\) , our detectors consist of very long (1–2 mm), narrow (0.4 \(\upmu \) m), and thin (0.25 \(\upmu \) m) Si \(_{x}\) N \(_{y}\) support beams that reduce the thermal conductance G between the substrate and the optical absorber. The thermistors of our lowest noise TESs consist of iridium with \(T_{c}=130\) mK. We have measured the electrical properties of arrays of these Ir TESs with various meander and straight support beams and absorber shapes and found that G is \(\sim \) 30 fW/K (meander) and \(\sim \) 110 fW/K (straight), the electrical NEP is 2–3  \(\times \)  10 \(^{-19}\) W/Hz \(^{1/2}\) (meander and straight), and the response time \(\tau \) is 10–30 ms (meander) and 2–5 ms (straight). To reduce spurious or “dark” power from heating the arrays, we mounted the arrays into light-tight niobium boxes and added custom L/R and L/C low-pass chip filters into these boxes to intercept dark power from the bias and readout circuit. We found the average dark power equals 1.3 and 4.6 fW for the boxes with L/R and L/C chip filters, respectively. We have built arrays with \(T_{c}= 70\)  mK using molybdenum/copper bilayers and are working to lower the dark power by an order of magnitude so we can demonstrate NEP \(~=~1~\times \)  10 \(^{-19}\)  W/Hz \(^{1/2}\) with these arrays. PACS numbers: 85.25.Pb; 95.85.Gn; 95.85.Fm; 63.22. \(+\) m     

Giant dielectric, low dielectric loss, and non-ohmic properties of nanocrystalline CaCu3Ti4O12

A simple polymer pyrolysis method has been successfully used to prepare CaCu₃Ti₄O₁₂ (CCTO) nanoparticles by calcination the obtained precursor powder at a low temperature of 800 (CCTO-1) and 850 °C (CCTO-2) in air for 4 h. The XRD results show that both of the calcined powders (CCTO-1 and CCTO-2) are pure having perovskite structure with the crystallite sizes, as evaluated by the XRD line boardening technique, of 47.5 and 75 nm, respectively. The particle sizes as estimated from the bright field images of TEM were found to be in the range of 10–35 and 7–52 nm for CCTO-1 and CCTO-2, respectively. The further sintering of CCTO-1 and CCTO-2 at 1,050 °C in air for 6 h, CCTO-1A and CCTO-2A, are also pure with perovskite structure as indicated by the XRD results. The measurements of the dielectric constant ( $ \varepsilon^{\prime } $ ε ′ ) and the low loss tangent (tanδ) at 1 kHz and 20 °C of CCTO-2A were found to be ~11,472 and ~0.0438, respectively. In addition, the CCTO-2A sample shows a small temperature coefficients ( $ \left| {\Updelta \varepsilon^{\prime } } \right| < 15\,\% $ | Δ ε ′ | < 15 % ) in a wide temperature range from ?50 to 110 °C. The non-Ohmic properties non-linear coefficient (α) of CCTO-1A and CCTO-2A were observed and the non-linear coefficient (α) of them determined in the range of 1–10 mA cm^?2 were found to be 12.00 and 7.26, respectively. Moreover, the breakdown field (E _b ) of CCTO-1A and CCTO-2A ceramics obtained at J = 1 mA cm^?2 were calculated and found to be 811 and 1,342 V cm^?1, respectively.     

Quantum Phase Transition in HTSC Thick Films: YBa2Cu3O x , YBa2Cu3O x (5 % Ag-Doped) in a Strong Pulsed Magnetic Field up to 32 T at Low Temperatures (58–100 K), Current Densities and Stress-Effect

We have researched the influence of pulsed magnetic fields up to 32 T on the magneto-resistance of thick films (50 Mk) of YBa₂Cu₃O _x and YBa₂Cu₃O _x (5 % Ag-doped) that were produced from synthesized powders. (Figs. 1–9): concentrate with 6.85–6.9 % O₂ and a tail fraction 6.5–6.6 % O₂. We observed a linear plot at currents of more than 1 mA at 77 K in YBa₂Cu₃O _x (5 % Ag-doped) at B>5 T and in the concentrate YBa₂Cu₃O _x samples with I=1 mA, T=68.2 K. Pulsed magnetic fields up to 32 T, at I=1 mA had practically no influence on the value of the magneto-resistance in the concentrate YBa₂Cu₃O _x specimens at T=57.9 K and up to 17 T for YBa₂Cu₃O _x (5 % Ag) at 77 K (Meissner effect). However, for B>17 T, YBa₂Cu₃O _x (5 % Ag) at 77 K demonstrates a tendency toward lower resistance. In the presence to 10 pulses in a cyclic pulsed magnetic field of 32 T, there is a sharp change of magnetic properties of an HTSC that can lead to nontrivial changes in the transition temperature, due to the strong mechanic stresses, sharp change value structure, and because one of the phases becomes superconducting (Figs. 3A, 3B). The behavior of the magnetoresistance of S-N-S contacts in pulsed magnetic fields is described via the system’s parallel resistance, R _n , and the inductance, L _S-N-S. Analysis of microscopic models of quantum phase transitions was made in a granular superconductor in an attempt to explain the results on the studied HTSC-films and to give a physical interpretation to the deduced parameters of some experiments on the basis of “spin (vortex) glass” (vortex ice).     

The power law relationship between citation impact and multi-authorship patterns in articles in Information Science &amp; Library Science journals

The aim of this paper is to extend the conversation about the correlation between collaboration and citation impact in articles in Information Science & Library Science journals by analyzing this correlation’s behavior using a power scaling law approach. 28,131 articles that received 215,693 citations were analyzed. The number of these articles that were published through collaboration accounts for 69%. In general, the scaling exponent of multi-authored articles, both international and domestic, increases over time while the exponent of single-authored papers decreases. The citation impact and collaboration patterns exhibit a power law correlation with a scaling exponent of 1.34 ± 0.02. Citations to multi-authored articles increased \(2^{1.34}\) or 2.53 times each time the number of multi-authored papers doubled. The Matthew Effect is stronger for multi-authored papers than for single-authored. The scaling exponent for the power law relationship of domestic multi-authored papers was 1.35 ± 0.02. The citations to domestic multi-authored articles increased \(2^{1.35}\) or 2.55 times each time the number of domestic multi-authored articles doubled. Contrary to previous studies we found that the Matthew Effect is stronger for domestic multi-authored papers than for international multi-authored ones.