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The pressure dependence of the static magnetic susceptibility χ(T) of the heavy-electron superconductor UBe13 was investigated over temperatures ranging from 1.5 to 300 K and at pressures from 1 bar to 8 kbar. It is linear in pressure over the full temperature range, having a small constant pressure dependence at higher temperatures that increases rapidly below about T=150 K. The maximal value of the relative susceptibility change [1/χ(dχ/dP)] is about 1% per kbar. The Curie-Weiss law is obeyed in the temperature range 100 to 300 K with the effective magnetic moment peff=3.46μB independent of pressure, while the paramagnetic Curie temperature FTHETA∼-100 K becomes more negative with pressure. The lattice parameter of cubic UBe13 was measured as a function of pressure, permitting a determination of a compressibility value of -9.2×10-4 kbar-1 near ambient pressure. The pressure dependence of χ(T) is significantly weaker than that of the specific-heat coefficient C(T)/T; we discuss whether this can be resolved by (i) consideration of intersite antiferromagnetic interactions, or (ii) the quadrupolar Kondo-effect model, and conclude that the latter provides a stronger explanation of the results. © 1993 The American Physical Society.

The electrical resistivity of the heavy-electron superconductor UBe13 was investigated over temperatures ranging from 1 to 300 K and at high pressures from 12 to 152 kbar. The temperature, Tmax, at which attains a maximum increases linearly with pressure at two limiting rates: 0.25 K/kbar below 30 kbar and 0.65 K/kbar above 30 kbar. At low temperatures, the -versus-T data can be described by the expression =0+AT2 over a temperature interval of 1 K at 12 kbar to more than 16 K at 152 kbar. The coefficient A can be related to the Fermi-liquid energy scale T* by A-1/2 T*. The pressure dependence of A-1/2 also increases linearly with pressure at two limiting rates, with a crossover at about 50 kbar. The similarity in the pressure dependences of Tmax and A-1/2 suggests that both parameters are proportional to a single energy scale, while the changes in pressure dependence of Tmax and A-1/2 may represent a crossover from heavy-fermion to intermediate-valence behavior. © 1990 The American Physical Society.

Specific-heat and dc magnetic-susceptibility measurements have been performed on RBa2Cu3Ox (R denotes rare earth) compounds. These measurements show that the rare-earth atoms behave as local moments above the superconducting transition temperature of these compounds which can be as high or higher than in nonmagnetic YBa2Cu3Ox. Further, we find coexistence of superconductivity and magnetism in R=Gd,Er,andDy compounds and evidence for crystalline-electric-field splittings in these materials. © 1987 The American Physical Society.

We report the first Knight-shift studies of the heavy-fermion superconducting state. In 5 kOe the Knight shift of muons in superconducting U1-xThxBe13 remains near the normal-state value for x=0.033, but shows an unexpected strong decrease for x=0. If the pairing is of odd parity, this decrease suggests that the anisotropic order parameter is pinned to the lattice. The qualitatively different behavior for x=0.033 reflects either spin-orbit scattering by Th doping or a change of pairing symmetry. © 1986 The American Physical Society.

The electrical resistivity of the heavy-electron superconductor UBe13 has been measured at temperatures T between 0.1 and 300 K for pressures P to 16 kbar and in magnetic fields H up to 9 T. The temperature Tmax at which shows a maximum increases linearly with P at H=0 and with H2 for P=14.8 kbar. The resistivity, when normalized to its value at Tmax(P), scales as a function of reduced temperature T/Tmax(P) from 1 K to 1/41.4Tmax. At P=14.8 kbar, the magnetoresistance -[R(H)-R(0)]/R(0) behaves as a universal function of H/T for 1T6 K and 0

We have determined the effect of hydrostatic pressure on the susceptibility, on the T2 temperature dependence of the spin-fluctuation resistivity, and on superconductivity in UPt3. The spin-fluctuation temperature Ts, derived from the slope of resistivity versus T2, is used within a Fermi-liquid picture to calculate the susceptibility at T=0 K. The depression of this calculated with pressure agrees with the directly measured value lnP=-24 Mbar-1. Both the superconducting transition temperature Tc and the initial slope of the upper critical field also decrease under pressure. We find that lnTc/P=-25 Mbar-1 and speculate upon correlations between and Tc. © 1985 The American Physical Society.

Heavy-electron metals exhibit highly correlated electronic behavior at liquid helium temperatures, with conduction-electron masses some hundred times the free-electron mass. Whether "normal," antiferromagnetic, or superconducting, their electronic behavior differs drastically from their ordinary metallic counterparts. The physical origin of the large mass and unusual superconducting and magnetic properties is the strong coupling between the conduction electrons and the local f-electron moment fluctuations characteristic of these materials.

Fluid capacity measurements on the heavy formion superconductor UPt3 in an 11T magnetic field show that aboveapproximately 7 K, UPt3 behaves like the spin fluctuation compounds UAl2 and TiB2. Magnetoresistance measurements on UPt3 at 1.2 K also yield results similar to UAl2 in contrast to the other heavy fermion superconductors CeCu3Si3 and UBe1, which show a magneticresistance effect of opposite sign. Thus, experimental results permit continued speculation of triplet superconductivity in UPt3. © 1984 Elsevier Science Publishers B.V.

In contrast to the other magnetic Rare Earth (RE) ions for which the cubic Laves REIr2 compound is ferromagnetic, YbIr2 and TmIr2 are antiferromagnetic below 0.40 and 0.05 K, respectively. Both are trivalent above 4 K, with a possible reduced moment for TmIr2 below 0.3 K. In addition, CeIr2 and LuIr2 are superconductive below 0.20 and 0.23 K, respectively. © 1985.

Gadolinium impurities in UBe13 depress the Tc at an initial rate of -0.40 K/%, while in Th0.029U0.971Be13 the initial rate is only -0.19 K/%. This strongly suggests two different superconducting states. Further data on thorium depressions and critical fields are presented. © 1987.

We have investigated the effects of impurities on the heavy fermion system U2Zn17. The Neél temperature of 9.7 K in pure U2Zn17 is strongly depressed to below 1.5 K with 2% Cu (on the Zn site) or 20% Th (on the U site). The electronic specific heat coefficient is practically independent of impurity concentration above any magnetic ordering temperature. © 1986.

We have measured the electrical resistivity, thermoelectric power, magnetic susceptibility, Hall coefficient and upper critical field near Tc in EuBa2Cu3Ox, where 6.09

We have investigated the effects of pressure on the magnetoresistance and the upper critical magnetic field of the heavy electron compound UBe13. Both the superconducting transition temperature and the upper critical field decrease under hydrostatic pressure. The low temperature magnetoresistance remains large and negative under pressure. The temperature region over which the resistivity has a T2 temperature dependence increases with both magnetic field and with pressure. At a fixed magnetic field, the coefficient of the T2 term in the resistivity decreases strongly with pressure. UBe13 is found to have a pressure independent intrinsic residual resistivity of 18 μΦcm. © 1987.

We have measured the magnetic moment of (La0.9Ba0.1)2CuO4- as a function of temperature and magnetic field and have found the onset of superconductivity at a temperature T {reversed tilde equals} 35 K. From the magnetic field dependencies, we have shown that the sample is a type-II superconductor with ≲ {reversed tilde equals} 11. Specific heat measurements yield a finite electronic specific heat coefficient of ∼6 mJ/mole-K2 at 4 K and a Debye temperature of only 330 K, suggesting that a strong electron-phonon interaction may be responsible for the high T in our sample. © 1987.

Resistivity of (Th, U)Be13 under pressure may show the restoration of the onset of electron coherence. Unseparated rare earth elements can be used for preparation of high-Tc superconductors. © 1987.

The longitudinal and transverse upper critical magnetic fields Hc2 and Hc2 as a function of temperature T of a single-crystal specimen of the heavy-fermion superconductor UPt3 were measured resistively with the current flowing along the hexagonal c axis. The slope of the linear part of the Hc2 (T) curve near the superconducting transition temperature Tc=0.52 K equals 63 kOe/K, from which a zero-temperature superconducting coherence length 3/401/4120 can be inferred. An analysis using previously reported specific-heat data yields an effective mass ~200 times the free-electron mass and a value of 3/401/4170. The electrical resistivity between Tc and 8 K varies as Tn with n=1.6±0.1. © 1984 The American Physical Society.

To gain into the formation of the heavy Fermion state in CeCu2Si2 we have studied the relationship between the high temperature and low temperature physical properties. The single crystals are grown from metallic solvents, such as Sn, In or Ga. The low temperature susceptibility χ can be varied by factors of 5, and samples with smallest χ have the largest linear contribution γ to the specific heat. This "anticorrelation" of χ and γ is unexpected. The reduction of χ at low T is mainly due to a temperature independent antiferromagnetic molecular-field type interaction χ-1(T)=χ-10(T)+λ, and not due to interactions which become dominant below a characteristic temperature. Superconductivity occurs in small χ - large γ samples. © 1985.

We report the discovery of a new phase diagram in the magnetic field-temperature plane for single crystals of La2CuO4 that show no sign of antiferromagnetic order. The phase boundary is defined by magneto-resistance and susceptibility measurements. We discuss several possibilities that may lead to the phase diagram observed. © 1988.

We report μ+ zero-field relaxation and Knight shift studies of the heavy-fermion superconductors U1-xThxBe13, x=0 and 0.033. The Knight shift in UBe13 shows a strong decrease as the temperature is reduced in the superconducting state, unlike U0.967Th0.033Be13 in which the shift remains at about the normal state value. If the superconducting state in UBe13 has odd-parity, the decrease of Kμ below Tc suggests that the order parameter is pinned to the lattice. Either spin-orbit scattering or the existence of two distinct superconducting states with different spin susceptibilities in the (U,Th)Be13 system would explain the differences observed in the Th-doped and pure UBe13 materials. The latter hypothesis would exclude conventional BCS superconductivity. No evidence for magnetic order is seen in the zero-field relaxation rate for either material down to 0.3 K. © 1986 J.C. Baltzer A.G., Scientific Publishing Company.

The effect of a few per cent of thorium replacing uranium in the heavy-fermion superconductor UBe13 is dramatic. The low-temperature properties are drastically altered and a second transition of a controversial nature occurs below the onset of superconductivity. Other non-magnetic impurities are seen from various preliminary measurements to yield promise of different results. Normally such impurity studies show only gradual changes in properties, which are useful for extracting superconducting parameters, but the large effects seen in this heavy-fermoin superconductor highlight its exotic nature. © 1985.

We report measurements of the superconducting and magnetic behavior of GdBa2Cu3Ox. Superconductivity occurs below Tc = 95 and 93 K, respectively, for these compounds with large Meissner effects observed. The Gd-based compound has an upper critical field slope -dHc2 dT greater than 1.2 T/K. Both compounds exhibit Curie-Weiss behavior above Tc with free-ion effective moments and small, negative temperature intercepts. In addition, the Gd-based compound orders antiferromagnetically below 2.24 K with an entropy consistent with the ordering of seven unpaired spins. © 1987.

Small amounts of Sc, Lu, Gd, Np, Ce, Th, La, and Ba have been substituted for uranium in UBe13 to observe their effects on the superconducting and normal state properties. The thorium, which was the most complete study, resulted in an extremely unusual nonmonotonic depression of the transition temperature for a nonmagnetic impurity. This comes from an interplay that exists between the lowest temperature resistivity peak and the transition temperature, as the peak is depressed. These results suggest that heavy Fermion superconductivity is only one of the possible ground states for heavy mass electron systems. All of the impurities tested resulted in a transition temperature depression.

Magnetic fields as small as 4 kOe substantially increase the resistivity of U1-xThxBe13 for x=0.0175 and 0.0378 between 1.4 K and Tc, the superconducting transition temperature of this heavy fermion material. At the intermediate value of x=0.026, Tc reaches a local maximum, and no normal-state field dependence is observed up to 4 kOe. At x=0.0603, away from the region of nonmonotonic dependence of T c on x, again no field dependence is seen. The observations are discussed with regard to specific-heat measurements and in terms of the interaction of superconductivity with narrowband features.

We have investigated the source of the anisotropic susceptibility of UZn8.5 by preparing single crystals of UxTh 1-xZn8.5 for small x. Preliminary indications are that anisotropic exchange, rather than crystal field effects, are responsible for the anisotropy, but possible impurity contributions to the (anisotropic) susceptibility of the ThZn8.5 do not permit a stronger statement. Further measurements for small x show that both the electronic specific heat and the susceptibility at low temperature are strongly enhanced, and that Kondo-type resistivity minima are observed. The enhancements are somewhat reduced in the concentrated system UZn8.5.

We present electrical-resistivity, magnetic-susceptibility, specific-heat, and thermal-expansion data for UCd11. The low-temperature specific heat indicates that the electronic subsystem has a highly enhanced specific heat which is partially removed by a phase transition at 5.0 K. © 1984 The American Physical Society.

We report magnetoresistance measurements of the heavy electron compound UBe13 above the superconducting transition temperature Tc and below 4 K for pressures P up to 19 kbar and for magnetic fields H up to 9 T. We observe strong negative magnetoresistance at all pressures and temperatures. The resistivity ρ is quadratic in temperature T from Tc up to a maximum temperature of 1 K at 1 bar increasing to 2 K at 19 kbar. The slope of the T2 term decreases with both H and with P. We find that δ(H)≡-[ρ(H)-ρ(0)]/ρ(0) for a given pressure scales as a function of H/T and exhibits power-law behavior over one decade with an exponent of 1.7. In addition, δ(H) at high pressure shows this same power law over a more limited H/T range.

Convincing evidence has been discovered for bulk superconductivity in UPt3 at 0.54 K based on specific-heat, resistance, and ac susceptibility measurements. In addition, new evidence is presented that indicates that UPt3 is a spin-fluctuation system. If true, this is the first coexistent superconductor spin-fluctuation system. © 1984 The American Physical Society.

We report the first thorough characterization of single crystals of CeCu2Si2. Measurements on these flux-grown crystals, which are not superconducting above 0.050 K, include ac susceptibility, resistivity, Hall effect, and specific heat. A review of other measurements is given, and the implications of our single-crystal data are discussed. Specifically, our data are consistent with superconductivity in CeCu2Si2 being destroyed by having too low a Kondo temperature, although TKondo is not found to be inversely proportional to as previously claimed. The entropy associated with the low-temperature specific-heat anomaly is found to be only 0.66R ln2, in contrast to the previous result of R ln2 for polycrystalline material. The lack of superconductivity in our single crystals does not appear to be due to poor stoichiometry to +5%, as proposed previously for single crystals grown by a Bridgman technique. The possibility of charge-density waves suppressing superconductivity in strain-free material is discussed, although no experimental verification is found. © 1983 The American Physical Society.

We have prepared single crystals of NpBe13, Np0.68U0.32Be13, and PuBe13 and measured their resistivity, susceptibility, and specific heat down to low temperatures. NpBe13 has an itinerant-electron magnetic transition at 3.4 K, with a large temperature-dependent specific heat above this transition that is quite similar to that observed in the heavy-fermion superconductor UBe13 and a (T=0) of approximately 900 mJ/mole K2. PuBe13 may be described as a Kondo-type system, with certain inconsistencies. The data are compared to results for UBe13 and are consistent with a narrow f band at the Fermi energy in UBe13 moving lower in energy with the addition of f electrons in heavier actinide elements to create a Kondo resonance by PuBe13. © 1984 The American Physical Society.

Actinide compounds exhibit most of the known magnetic phenomena. Their properties are easily modified in intermetallic compounds. We present some new results on uranium ferromagnets and heavy fermion antiferromagnets and explain their implications. We show magnetic ordering in a high Tc superconductor. © 1987.

Results of measurements of the electrical resistivity ρ{variant} between 0.04 and 1 K and the specific heat cp between 0.06 and 1 K of annealed polycrystalline CeCu6 are reported. ρ{variant} varies proportional to T2 below 0.1 K but is linear in T above 0.6 K. The specific heat is proportional to T below 0.5 K and the electronic specific-heat parameter γ = 1.53 J mole K2. © 1985.

Magnetic fields as small as 4 kOe substantially increase the resistivity of U1-xThxBe13 for x=0.0175 and 0.0378 between 1.4 K and Tc, the superconducting transition temperature of this heavy fermion material. At the intermediate value of x=0.026, Tc reaches a local maximum, and no normal-state field dependence is observed up to 4 kOe. At x=0.0603, away from the region of nonmonotonic dependence of T c on x, again no field dependence is seen. The observations are discussed with regard to specific-heat measurements and in terms of the interaction of superconductivity with narrowband features.

We have investigated the source of the anisotropic susceptibility of UZn8.5 by preparing single crystals of UxTh 1-xZn8.5 for small x. Preliminary indications are that anisotropic exchange, rather than crystal field effects, are responsible for the anisotropy, but possible impurity contributions to the (anisotropic) susceptibility of the ThZn8.5 do not permit a stronger statement. Further measurements for small x show that both the electronic specific heat and the susceptibility at low temperature are strongly enhanced, and that Kondo-type resistivity minima are observed. The enhancements are somewhat reduced in the concentrated system UZn8.5.

HEPScore is a new CPU benchmark created to replace the HEPSPEC06 benchmark that is currently used by the WLCG for procurement, computing resource pledges, usage accounting and performance studies. The development of the new benchmark, based on HEP applications or workloads, has involved many contributions from software developers, data analysts, experts of the experiments, representatives of several WLCG computing centres and WLCG site managers. In this contribution, we review the selection of workloads and the validation of the new HEPScore benchmark.

Describes a means for determining student knowledge in science. Written in student-level language, WALLS contains statements about science knowledge within bricks on a worksheet. Students shade in bricks they know or activities they have done and part-shade any they are unsure about, giving a differentiated starting point that allows them to plan their own learning with the teacher. (PVD)

Abstract Background Next-generation sequencing technologies generate a significant number of short reads that are utilized to address a variety of biological questions. However, quite often, sequencing reads tend to have low quality at the 3’ end and are generated from the repetitive regions of a genome. It is unclear how different alignment programs perform under these different cases. In order to investigate this question, we use both real data and simulated data with the above issues to evaluate the performance of four commonly used algorithms: SOAP2, Bowtie, BWA, and Novoalign. Methods The performance of different alignment algorithms are measured in terms of concordance between any pair of aligners (for real sequencing data without known truth) and the accuracy of simulated read alignment. Results Our results show that, for sequencing data with reads that have relatively good quality or that have had low quality bases trimmed off, all four alignment programs perform similarly. We have also demonstrated that trimming off low quality ends markedly increases the number of aligned reads and improves the consistency among different aligners as well, especially for low quality data. However, Novoalign is more sensitive to the improvement of data quality. Trimming off low quality ends significantly increases the concordance between Novoalign and other aligners. As for aligning reads from repetitive regions, our simulation data show that reads from repetitive regions tend to be aligned incorrectly, and suppressing reads with multiple hits can improve alignment accuracy. Conclusions This study provides a systematic comparison of commonly used alignment algorithms in the context of sequencing data with varying qualities and from repetitive regions. Our approach can be applied to different sequencing data sets generated from different platforms. It can also be utilized to study the performance of other alignment programs.

Abstract Background Complementary and alternative medicines (CAMs) are being used increasingly across the world. In Australia, community pharmacists are a major supplier of these products but knowledge of the products and interactions with other medicines is poor. Information regarding the use of CAMs by metropolitan pharmacists has been documented by the National Prescribing Service (NPS) in Australia but the views of rural/regional community pharmacists have not been explored. The aim of this pilot study was to explore the knowledge, attitudes and information seeking of a cohort of rural community pharmacists towards CAMs and to compare the findings to the larger NPS study. Methods A cross sectional self-administered postal questionnaire was mailed to all community pharmacists in one rural/regional area of Australia. Using a range of scales, data was collected regarding attitudes, knowledge, information seeking behaviour and demographics. Results Eighty eligible questionnaires were returned. Most pharmacists reported knowing that they should regularly ask consumers if they are using CAMs but many lacked the confidence to do so. Pharmacists surveyed for this study were more knowledgeable in regards to side effects and interactions of CAMs than those in the NPS survey. Over three quarters of pharmacists surveyed reported sourcing CAM information at least several times a month. The most frequently sought information was drug interactions, dose, contraindications and adverse effects. A variety of resources were used to source information, the most popular source was the internet but the most useful resource was CAM text books. Conclusions Pharmacists have varied opinions on the use of CAMs and many lack awareness of or access to good quality CAMs information. Therefore, there is a need to provide pharmacists with opportunities for further education. The data is valuable in assisting interested stakeholders with the development of initiatives to address the gaps in attitudes, knowledge and to improve effectiveness of information seeking behaviour.

Abstract Background Clinical pathways are tools used to guide evidence-based healthcare that have been implemented internationally since the 1980s. However, there is widespread lack of agreement on the impact of clinical pathways on hospital resources and patient outcomes. This can be partially attributed to the confusion for both researchers and healthcare workers regarding what constitutes a clinical pathway. This paper describes efforts made by a team of Cochrane Review authors to develop criteria to assist in the objective identification of clinical pathway studies from the literature. Methods We undertook a four-stage process aiming to develop criteria to define a clinical pathway: (1) identify publications exploring the definition of a clinical pathway; (2) derive draft criteria; (3) pilot test the criteria; and (4) modify criteria to maximise agreement between review authors. Results Previous literature and liaison with the European Pathways Association resulted in five criteria being used to define a clinical pathway: (1) the intervention was a structured multidisciplinary plan of care; (2) the intervention was used to translate guidelines or evidence into local structures; (3) the intervention detailed the steps in a course of treatment or care in a plan, pathway, algorithm, guideline, protocol or other 'inventory of actions'; (4) the intervention had timeframes or criteria-based progression; and (5) the intervention aimed to standardise care for a specific clinical problem, procedure or episode of healthcare in a specific population. After pilot testing it was decided that if an intervention met the first criteria (a structured multidisciplinary plan of care) plus three out of the other four criteria then it was included as a clinical pathway for the purposes of this review. In all, 27 studies were included in the final review. The authors of the included studies referred to these interventions as 'clinical pathways', 'protocols', 'care model', 'care map', 'multidisciplinary care', evidence-based care' and 'guideline'. Conclusions The criteria used for the identification of relevant studies for this Cochrane Review can be used as a foundation for the development of a standardised, internationally accepted definition of a clinical pathway.

Abstract Background People living in rural Australia are more likely to die in hospital following an acute myocardial infarction than those living in major cities. While several factors, including time taken to access hospital care, contribute to this risk, it is also partially attributable to the lower uptake of evidence-based guidelines for the administration of thrombolytic drugs in rural emergency departments where up to one-third of eligible patients do not receive this life-saving intervention. Clinical pathways have the potential to link evidence to practice by integrating guidelines into local systems, but their impact has been hampered by variable implementation strategies and sub-optimal research designs. The purpose of this study is to determine the impact of a five-step clinical pathways implementation process on the timely and efficient administration of thrombolytic drugs for acute myocardial infarctions managed in rural Australian emergency departments. Methods/Design The design is a two-arm, cluster-randomised trial with rural hospital emergency departments that treat and do not routinely transfer acute myocardial infarction patients. Six rural hospitals in the state of Victoria will participate, with three in the intervention group and three in the control group. Intervention hospitals will participate in a five-step clinical pathway implementation process: engagement of clinicians, pathway development according to local resources and systems, reminders, education, and audit and feedback. Hospitals in the control group will each receive a hard copy of Australian national guidelines for chest pain and acute myocardial infarction management. Each group will include 90 cases to give a power of 80% at 5% significance level for the two primary outcome measures: proportion of those eligible for thrombolysis receiving the drug and time to delivery of thrombolytic drug. Discussion Improved compliance with thrombolytic guidelines via clinical pathways will increase acute myocardial infarction survival rates in rural hospitals and thereby help to reduce rural-urban mortality inequalities. Such knowledge translation has the potential to be adapted for a range of clinical problems in a wide array of settings. Trial registration Australia New Zealand Clinical Trials Registry code ACTRN12608000209392.

This article memorializes Colin D. Elliott (1937-2016). For 7 years, in his work as a school psychologist, Elliott studied the ability profiles of children with learning disabilities and the measurement of children's developmental stages. Subsequently, he trained school psychologists for over 20 years at the University of Manchester. In 1983, he made a major, enduring contribution to the field of psychometric assessment in both his home country and the wider field with the publication of the innovative British Ability Scales (BAS). An American version, the Differential Ability Scales (DAS), followed in 1990, and both versions of the test have been widely used and revised several times (BAS 2, BAS 3, and DAS-II). Many of his innovations in those tests have been adopted in other instruments. His other research and many publications focused on individual differences in children's temperament and personality and specific learning difficulties. Elliott moved to the United States in 1992 and was adjunct professor at the Gevirtz Graduate School of Education at the University of California, Santa Barbara. (PsycINFO Database Record, ((c) 2017 APA, all rights reserved).)