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Esophageal perforation after endoscopic ultrasound-guided fine-needle aspiration for mediastinal staging is a rare but severe complication. We report 2 cases of patients with esophageal perforation who were treated using video-assisted thoracoscopic surgery in combination with esophageal stenting. Through these cases, the feasibility of minimally invasive thoracic surgery was evaluated.

The Nile perch (Lates niloticus) is a notorious invasive species. The introductions of Nile perch into several lakes and rivers in the Lake Victoria region led to the impoverishment of the trophic food webs, particularly well documented in Lake Victoria. Along with the introductions of the Nile perch, its parasites were co-introduced. Dolicirroplectanum lacustre (Monogenea, Diplectanidae) is a gill parasite of latid fishes (Lates spp.) inhabiting several major African freshwater systems. We examined the intra-specific diversification of D. lacustre from L. niloticus in Lake Albert (native range) and Lake Victoria (introduced range) by assessing morphological and genetic differentiation, and microhabitat preference. We expected reduced morphological and genetic diversity for D. lacustre in Lake Victoria compared to Lake Albert, as a result of the historical introductions. Dolicirroplectanum lacustre displays high morphological variability within and between African freshwaters. Mitonuclear discordance within the morphotypes of D. lacustre indicates an incomplete reproductive barrier between the morphotypes. The diversification in the mitochondrial gene portion is directly linked with the morphotypes, while the nuclear gene portions indicate conspecificity. Based on our results, we reported reduced genetic and morphological diversity, potentially being a result of a founder effect in Lake Victoria.

Introduction/Background* High cancer risks, as applicable to BRCA1 and BRCA2 pathogenic variant (PV) carriers, can induce significant cancer concerns. We examined the degree of cancer worry and the course of this worry among BRCA1/2-PV carriers opting for surgery to prevent ovarian cancer, and identified factors associated with high cancer worry. Methodology Cancer worry was evaluated as part of the multicentre, prospective TUBA-study (NCT02321228) in which BRCA1/2-PV carriers choose between the standard risk-reducing salpingo-oophorectomy or a novel strategy, risk-reducing salpingectomy with delayed oophorectomy. The Cancer Worry Scale was obtained before and three and twelve months after surgery. Cancer worry patterns were analysed using latent class growth analysis and factors associated with cancer worry were identified with regression analysis. Result(s)* Of all 577 BRCA1/2-PV carriers, 320 (55.5%) had high (≥14) cancer worry pre-surgery and 70.2% had higher cancer worry pre-surgery than post-surgery. Based on the course of cancer worry, BRCA1/2-PV carriers could be classified into three groups: persistently low cancer worry (56.4%), persistently high cancer worry (6.3%), and fluctuating cancer worry that mainly declined over time (37.3%). Factors associated with persistently high cancer concerns were: age below 35 (BRCA1) or 40 (BRCA2) years, unemployment, previous breast cancer diagnosis, lower education and more recent diagnosis with the BRCA-PV. Conclusion* High cancer worry is common among BRCA1/2-PV carriers and mainly declines after risk-reducing surgery. However, cancer worry remains high in 6% of the women and they should be identified and offered support. It should be realized that in this group, surgery does not reduce cancer concerns.

There is an ongoing dispute in the community about the absence of a magnetic quantum critical point (QCP) in the noncentrosymmetric heavy fermion compound CeRhSi

A new U-based compound of the U2Rh2Pb, a new compound of the U2T2X series was prepared in a single-crystal form. Its structure was determined as belonging to the tetragonal Mo2FeB2 structure type with the shortest U-U spacing along the c. U2Rh2Pb undergoes an antiferromagnetic transition at TN of 20 K and exhibits an enhanced Sommerfeld coefficient 150 mJ/molK2. In contrast to the two rhodium analogues U2Rh2In and U2Rh2Sn, the easy-magnetization direction is the c with rather low value of the critical field 4.3 T of the metamagnetic transition of a spin-flip type. The observed dependences of TN and Hc on temperature and magnetic field have been used for constructing a magnetic phase diagram. The experimental observations are mostly supported by first-principles calculations., Comment: https://www.sciencedirect.com/science/article/pii/S0925838819347310

There is an ongoing dispute in the community about the absence of a magnetic quantum critical point (QCP) in the noncentrosymmetric heavy fermion compound CeRhSi3. In order to explore this question we prepared single crystals of CeRh(Si1-x Ge x )3 with x = 0.05 and 0.15 and determined the temperature-pressure (T-p) phase diagram by means of measurements of the electrical resistivity. The substitution of isoelectronic but large Ge enforces a lattice volume increase resulting in a weakening of the Kondo interaction. As a result, the x = 0.05 and x = 0.15 compound exhibit a transition into the antiferromagnetic (AFM) at higher temperatures being T N = 4.7 K and T N1 = 19.7 K, respectively. Application of pressure suppresses T N (T N1) monotonically and pressure induced superconductivity is observed in both Ge-substituted compounds above p ⩾ 2.16 GPa (x = 0.05) and p ⩾ 2.93 GPa (x = 0.15). Extrapolation of T N(p) → 0 of CeRh(Si0.95Ge0.05)3 yields a critical pressure of p c ≈ 3.4 GPa (in CeRh(Si0.85Ge0.15)3 p c ≈ 3.5 GPa) pointing to the presence of an AFM QCP located deep inside the superconducting state.

We report on the single crystal properties of the novel U$_{2}$RhIn$_{8}$ compound studied in the context of parent URhIn$_{5}$ and UIn$_{3}$ systems. The compounds were prepared by In self-flux method. U$_{2}$RhIn$_{8}$ adopts the Ho$_{2}$CoGa$_{8}$-type structure with lattice parameters a $= 4.6056(6)$ \AA\ and c $= 11.9911(15)$ \AA. The behavior of U$_{2}$RhIn$_{8}$ strongly resembles that of the related URhIn$_{5}$ and UIn$_{3}$ with respect to magnetization, specific heat and resistivity except for magnetocrystalline anisotropy developing with lowering dimensionality in the series UIn$_{3}$ vs. U$_{2}$RhIn$_{8}$ and URhIn$_{5}$. U$_{2}$RhIn$_{8}$ orders antiferromagnetically below T$_{\textrm{N}}$ $= 117$ K and exhibits a slightly enhanced Sommerfeld coefficient $\gamma = 47$ mJ$\cdot$mol$^{-1}\cdot$K$^{-2}$. Magnetic field leaves the value of N\'{e}el temperature for both URhIn$_{5}$ and U$_{2}$RhIn$_{8}$ unaffected up to 9 T. On the other hand, T$_{\textrm{N}}$ is increasing with applying hydrostatic pressure up to 3.2 GPa. The weak temperature dependence of $\chi(T)$ in all studied compounds might be attributed to the mainly itinerant nature of 5f electrons. The character of uranium 5f electron states of U$_{2}$RhIn$_{8}$ was studied by first principles calculations based on the density functional theory. The overall phase diagram of U$_{2}$RhIn$_{8}$ is discussed in the context of magnetism in the related URhX$_{5}$ and UX$_{3}$ (X = In, Ga) compounds.

We report on the results of a de Haas--van Alphen (dHvA) measurement performed on the recently discovered antiferromagnet ${\mathrm{URhIn}}_{5}$ (${T}_{N}=98$ K), a $5f$ analog of the well studied heavy fermion antiferromagnet ${\mathrm{CeRhIn}}_{5}$. We observe two small Fermi surfaces: a roughly spherical pocket $\ensuremath{\beta}$, with ${F}_{\ensuremath{\beta}}\ensuremath{\simeq}0.3$ kT, and a pillow-shaped closed surface, $\ensuremath{\alpha}$, with ${F}_{\ensuremath{\alpha}}\ensuremath{\simeq}1.1$ kT. In addition, we observe two higher frequencies ${\ensuremath{\gamma}}_{1}$ with ${F}_{{\ensuremath{\gamma}}_{1}}\ensuremath{\simeq}3.2$ kT and ${\ensuremath{\gamma}}_{2}$ with ${F}_{{\ensuremath{\gamma}}_{2}}\ensuremath{\simeq}3.5$ kT that are seen only near the $c$ axis, and that may arise on cylindrical Fermi surfaces. The measured cyclotron masses range from $1.9{m}_{e}$ to $4.3{m}_{e}$. A simple LDA+SO calculation performed for the paramagnetic ground state shows a very different Fermi surface topology, demonstrating a need for more advanced electronic structure calculations.

Clathrates are candidate materials for thermoelectric applications because of a number of unique properties. The clathrate I phases in the Ba-Ni-Ge ternary system allow controlled variation of the charge carrier concentration by adjusting the Ni content. Depending on the Ni content, the physical properties vary from metal-like to insulator-like and show a transition from p-type to n-type conduction. Here we present first results on the characterization of millimeter-sized single crystals grown by the Bridgman technique. Single crystals with a composition of Ba8Ni3.5Ge42.1□0.4 show metallic behavior (dρ/dT > 0) albeit with high resistivity at room temperature [ρ (300 K) = 1 mΩ cm]. The charge carrier concentration at 300 K, as determined from Hall-effect measurements, is 2.3 e−/unit cell. The dimensionless thermoelectric figure of merit estimated at 680 K is ZT ≈ 0.2.

In order to disentangle the effects of the two different crystallographic Ce sites in Ce 3 Pd 20 Si 6 on the intriguing low-temperature properties of this compound, we have investigated polycrystalline samples of Ce 3-x Lu x Pd 20 Si 6 (x = 1, 2) and Ce 3-y La y Pd 20 Si 6 (y = 1, 2). The lattice parameters and electrical resistivity measurements in the temperature range 2-300 K are presented. Lu-substitution leads to a considerable decrease in the unit cell volume, corresponding to positive chemical pressure, while substitution with La expands the lattice much more gradually. We interpret the observed shifts in the characteristic temperatures for the onset of incoherent and coherent Kondo scattering, T min and T max , respectively, by competing effects of chemical pressure and density of Kondo scatterers. We also investigate the important issue of preferential site occupation by Lu and La and present evidence for Ce 2 LaPd 20 Si 6 being an essentially ordered compound. The incoherent Kondo scattering dominating the electrical resistivity of Ce 3 Pd 20 Si 6 between 20 and 300 K appears to be caused by Ce at the 8c-site only.

Many current research efforts in strongly correlated systems focus on the interplay between magnetism and superconductivity. Here we report on coexistence of both cooperative ordered states in recently discovered stoichiometric and fully inversion symmetric heavy fermion compound Ce3PdIn11 at ambient pressure. Thermodynamic and transport measurements reveal two successive magnetic transitions at T1 = 1.67 K and TN = 1.53 K into antiferromagnetic type of ordered states. Below Tc = 0.42 K the compound enters a superconducting state. The large initial slope of dBc2/dT ≈ – 8.6 T/K indicates that heavy quasiparticles form the Cooper pairs. The origin of the two magnetic transitions and the coexistence of magnetism and superconductivity is briefly discussed in the context of the coexistence of the two inequivalent Ce-sublattices in the unit cell of Ce3PdIn11 with different Kondo couplings to the conduction electrons.

We report on synthesis and anisotropic physical properties of URhIn$_{5}$. High quality single crystals were grown in In-flux. The compound undergoes a second order phase transition into an antiferromagnetic state at T$_{\textrm{N}}$ = 98 K. The transition is field independent up to 9 T. An increase of the resistivity $\rho$ with j along the [100], [110] and [001] tetragonal axis indicates a spin-density-wave induced order with the gap opening first along the [001] direction. The magnetic susceptibility $\chi$ = M/H exhibits a strong anisotropy. Above T $=$ 200 K, $\chi$(T) follows Curie-Weiss law with the effective moment of $\mu_{\textrm{eff}}$ = 3.71 $\mu_{\textrm{B}}/$U and the Weiss temperatures of $\theta_{\textrm{P}}^{[100]} = -900$ K and $\theta_{\textrm{P}}^{[001]} = -500$ K for H $\parallel$ [100] and H $\parallel$ [001] respectively. The characteristic Kondo-like temperature for URhIn$_{5}$ yields T$_{\textrm{K}} =$ 125 K.

We discuss recent low-temperature measurements on single-crystalline samples of the heavy fermion compounds YbRh2(Si1−xGex)2 (TK = 30 K) with x = 0 and 0.05 (nominal). Both show weak antiferromagnetic (AF) order at TN = 70 and 20 mK respectively. At the field-induced quantum critical point (QCP) that occurs at B = Bc ≈ 0.06 T (B ⊥ c) for the pure compound, non-Fermi-liquid properties are observed down to the lowest accessible temperatures (≈10 mK). These are caused by quantum critical AF fluctuations predominating over the competing ferromagnetic ones. At B = 0 and for TN < T < 0.3 K, both compounds show a magnetic susceptibility which follows a Curie–Weiss law with a surprisingly large effective moment of 1.4 μB, and a Sommerfeld coefficient of the electronic specific heat which deviates towards large values from the theoretically expected (− log T) dependence observed above T = 0.3 K. This observation is in striking contrast to the linear T dependence of the electrical resistivity found down to T ≈ 10 mK. It suggests a break up of the heavy fermion in the approach to the B = 0 QCP that occurs at a slightly larger Ge concentration.

We discuss recent results obtained for the heavy-fermion metals UPd2Al3 and YbRh2Si2. UPd2Al3 is the first among all superconductors for which tunneling and inelastic neutron-scattering data highlight a non-phononic, i.e., magnetic-exciton mediated, pair state. YbRh2Si2 represents a model system exhibiting pronounced non-Fermi liquid effects above a weak antiferromagnetic phase transition at T N =70 mK . Upon approaching the quantum critical point (TN→0), by low doping with Ge, one observes for T K disparate behavior in the temperature dependences of both the electrical resistivity and the electronic specific heat as well as a Curie–Weiss law in the uniform magnetic susceptibility, implying uncompensated large 4f moments. These observations indicate a break up of the composite quasiparticles into their local f-spin and itinerant conduction-electron parts.

We discuss a series of thermodynamic, magnetic, and electrical transport experiments on the two heavy fermion compounds CeNi2Ge2 and YbRh2Si2 in which magnetic fields, B, are used to tune the systems from a non-Fermi liquid (NFL) into a field-induced FL state. Upon approaching the quantum-critical points from the FL side by reducing B we analyze the heavy quasiparticle (QP) mass and QP-QP scattering cross sections. For CeNi2Ge2 the observed behavior agrees well with the predictions of the spin-density wave (SDW) scenario for three-dimensional (3D) critical spin-fluctuations. By contrast, the observed singularity in YbRh2Si2 cannot be explained by the itinerant SDW theory for neither 3D nor 2D critical spinfluctuations. Furthermore, we investigate the magnetization M(B) at high magnetic fields. For CeNi2Ge2 a metamagnetic transition is observed at 43 T, whereas for YbRh2Si2 a kink-like anomaly occurs at 10 T in M vs B (applied along the easy basal plane) above which the heavy fermion state is completely suppressed.

The transport properties of the semimetallic quasi-one-dimensional S=1/2 antiferromagnet Yb4As3 have been studied by performing low-temperature (T≥0.02 K) and high magneticfield (B≤60 T) measurements of the electrical resistivity ρ(T, B). For T ≿ 2 K a ‘heavy-fermion’-like behavior Δρ(T)=AT2 with huge and nearly field-independent coefficient A ≈ 3 µΩ cm/K2 is observed, whereas at lower temperatures ρ(T) deviates from this behavior and slightly increases to the lowest T. In B>0 and T ≾ 6 K the resistivity shows an anomalous magnetic-history dependence together with an unusual relaxation behavior. In the isothermal resistivity Shubnikov-de Haas (SdH) oscillations, arising from a low-density system of mobile As-4p holes, with a frequency of 25 T have been recorded. From the T- and B-dependence of the SdH oscillations an effective carrier mass of (0.275±0.005)m0 and a charge-carrier mean-free path of 215 A are determined. Furthermore, in B≥15 T, the system is near the quantum limit and spin-splitting effects are observed.

Tiotropium (Spiriva) is a new once-daily inhaled anticholinergic that has its effect through prolonged muscarinic (M)3 receptor antagonism. It has a clinically documented, long duration of action with once-daily dosing in chronic obstructive pulmonary disease (COPD). A single-centre, double-blind, ipratropium-controlled study was conducted in order to characterize the onset of pharmacodynamic steady state of tiotropium in patients with COPD. Thirty-one patients (25 male, six female) with a mean age of 62 yrs and a mean forced expiratory volume in one second (FEV1) of 1.13 L (38% of predicted) were randomly assigned to receive either tiotropium 18 microg once-daily from a dry-powder inhaler (HandiHaler, 20 patients), or ipratropium 40 microg four-times daily from a pressurized metered-dose inhaler (11 patients) for a period of 1 week. FEV1 and forced vital capacity (FVC) were measured 1 h prior to, and just before inhalation (mean value of the two measurements on test-day 1 was the baseline value, while on all other test days it was the trough value), and 0.5, 1, 2, 3, 4, 5, and 6 h after inhalation of the morning dose of the study drug (one capsule and two puffs) on days 1, 2, 3, and 8. Trough FEV1 following 8 days of tiotropium was 0.19 L (18%) above baseline. Approximately 90% of this increase was achieved within 24 h of the first dose (0.17 L, 16%). Trough FVC increased 0.67 L (27%) on test-day 8. Approximately 70% of the improvement was observed after two tiotropium doses (0.47 L, 19%). Achievement of FVC steady state was delayed compared to FEV1. Ipratropium performed typically with an onset of action within 30 min, a peak response between 1-2 h postdosing and a duration of action of approximately 4 h. It was concluded that forced expiratory volume in one second steady state with tiotropium is reached within 48 h, while continued improvements in forced vital capacity can be expected over or beyond the first week of therapy. The continued increases in forced vital capacity beyond 48 h suggests that maintenance bronchodilator therapy is required to achieve maximal changes in hyperinflation.

The semimetallic quasi-one-dimensional S= 1 2 antiferromagnet Yb4As3 has been studied by performing low-temperature (T) and high magnetic-field (B) measurements of the specific heat, C(T,B), magnetization, M(T,B), AC-susceptibility, χAC(T,B), and electrical resistivity, ρ(T,B). At finite transverse magnetic fields, a gap Δ(B) is induced in the low-energy magnetic excitation spectrum. Our C(T,B) measurements reveal a Δ(B)∼B2/3 dependence for B⩽9 T, in accordance with predictions of the quantum sine-Gordon model. At higher fields the Δ(B) curve levels-off gradually. In the isothermal magnetization taken at 0.6 K no saturation occurs up to 60 T. We also present new results on spin-glass behavior below 0.15 K caused by a weak ferromagnetic interchain coupling and disorder. Finally, we concentrate on the electrical transport properties. Shubnikov-de Haas oscillations, arising from a low-density system of mobile As-4p holes, are recorded in magnetic fields up to 60 T. We estimate the effective mass and the mean-free path of these carriers and discuss spin-splitting effects.

We report on single crystal growth and crystallographic parameters results of Ce$_2$PdIn$_8$, Ce$_3$PdIn$_{11}$, Ce$_2$PtIn$_8$ and Ce$_3$PtIn$_{11}$. The Pt-systems Ce$_2$PtIn$_8$ and Ce$_3$PtIn$_{11}$ are synthesized for the first time. All these compounds are member of the Ce$_n$T$_m$In$_{3n+2m}$ (n = 1, 2,..; m = 1, 2,.. and T = transition metal) to which the extensively studied heavy fermion superconductor CeCoIn$_5$ belongs. Single crystals have been grown by In self-flux method. Differential scanning calorimetry studies were used to derive optimal growth conditions. Evidently, the maximum growth conditions for these materials should not exceed 750 $^{\circ}$C. Single crystal x-ray data show that Ce$_2$TIn$_8$ compounds crystallize in the tetragonal Ho$_2$CoGa$_8$ phase (space group P4/mmm) with lattice parameters a =4.6898(3) $\AA$ and c =12.1490(8) $\AA$ for the Pt-based one (Pd: a = 4.6881(4) $\AA$ and c = 12.2031(8) \AA). The Ce$_3$TIn$_{11}$ compounds adopt the Ce$_3$PdIn$_{11}$ structure with a = 4.6874(4) $\AA$ and c = 16.8422(12) $\AA$ for the Pt-based one (Pd: a = 4.6896 $\AA$ and c = 16.891 \AA). Specific heat experiments on Ce$_3$PtIn$_{11}$ and Ce$_3$PdIn$_{11}$ have revealed that both compounds undergo two successive magnetic transitions at T$_1$ ~ 2.2 K followed by T$_N$ ~ 2.0 K and T$_1$ ~ 1.7 K and T$_N$ ~ 1.5 K, respectively. Additionally, both compounds exhibit enhanced Sommerfeld coefficients yielding {\gamma}$_{Pt}$ = 0.300 J/mol K$^2$ Ce ({\gamma}$_{Pd}$ = 0.290 J/mol K$^2$ Ce), hence qualifying them as heavy fermion materials.

We investigate a new route to quasi-one-dimensional spin-chain systems which originates from the charge-ordering transition out of a homogeneous mixed-valence state. We present evidence that Yb4As3 and P, Sb doped mixed crystals are well described by this mechanism. Many thermodynamic and low-temperature transport heavy-fermion-like properties can be explained by the existence of low-lying quasi-one-dimensional spin excitations in the Yb3+-chains. The observation of soliton excitations in a transverse external field gives further support to the existence of spin chains in Yb4As3. We also present recent results on spin-glass behavior at very low temperature caused by the interchain coupling and disorder. In addition, the yet unexplained magnetotransport effects are discussed.

The well known intermetallic compound YbRh 2 Si 2 (tetragonal ThCr 2 Si 2 structure) is a heavy fermion system which orders antiferromagnetically at T N = 70 mK . Application of a magnetic field suppresses the Neel temperature continuously to zero and thus accesses a magnetic-field induced quantum critical point (QCP). The Hall coefficient shows a broadened step-like decrease as a function of applied field which extrapolates, at T = 0 , to a sharp step at the QCP, indicating that this QCP is not of spin density wave type. The iso-structural compound YbIr 2 Si 2 (I-type) does not order magnetically down to the lowest temperatures but does, nevertheless, show non-Fermi liquid behaviour in wide regions of the temperature-field phase diagram. Here we use field-dependent Hall-effect measurements as a probe of a putative nearby QCP in YbIr 2 Si 2 .

A single crystal of Ce 3 Rh 4 Sn 13 has been investigated by means of electrical resistivity at low temperatures and in high magnetic fields. Measurements have been performed with field parallel to the [1 0 0] and [1 1 0] direction. Several transitions, first and second order ones, are observed, which originate from the entrance into a different antiferromagnetic states. Our data complement the phase diagram derived in previous work. We speculate that the origin of the antiferromagnetic transitions is related to the slight off-stoichiometry of the sample.

The cage compound Ce 3 Pd 20 Si 6 has recently been shown to undergo two successive low-temperature phase transitions which are strongly affected by an applied magnetic field. Here we show that, as the lower, probably antiferromagnetic transition is suppressed to zero in a field slightly above 1 T, the electrical resistivity shows a non-Fermi-liquid-like linear-in- T temperature dependence while it follows the usual Fermi liquid T 2 temperature dependence both at smaller and larger fields. This suggests that a field-induced quantum critical point exists in Ce 3 Pd 20 Si 6 .

We report on detailed low temperature measurements of the magnetization, the specific heat and the electrical resistivity on high quality CeRuSn single crystals. The compound orders antiferromagnetically at $T_{\rm N} = 2.8$ K with the Ce$^{3+}$ ions locked within the $a-c$ plane of the monoclinic structure. Magnetization shows that below $T_{\rm N}$ CeRuSn undergoes a metamagnetic transition when applying a magnetic field of 1.5 and 0.8 T along the $a$ and $c$--axis, respectively. This transition manifests in a tremendous negative jump of $\sim 25$% in the magnetoresistance. The value of the saturated magnetization along the easy magnetization direction ($c$--axis) and the magnetic entropy above $T_{\rm N}$ derived from specific heat data correspond to the scenario where only one third of the Ce ions in the compound being trivalent and carrying a stable Ce$^{3+}$ magnetic moment, whereas the other two thirds of the Ce ions are in a nonmagnetic tetravalent and/or mixed valence state. This is consistent with the low temperature CeRuSn crystal structure i.\,e.\,, a superstructure consisting of three unit cells of the CeCoAl-type piled up along the $c$--axis, and in which the Ce$^{3+}$ ions are characterized by large distances from the Ru ligands while the Ce-Ru distances of the other Ce ions are much shorter causing a strong 4{\it f}-ligand hybridization and hence leading to tetravalent and/or mixed valence Ce ions., 13 pages, 5 figures

We discuss the results of thermodynamic and transport measurements at ambient and under hydrostatic pressure of the recently discovered heavy fermion superconductor Ce3PtIn11. At p = 0 superconductivity emerges in the complex antiferromagnetic state below Tc = 0.32 K. Both phenomena coexist in a wide range of the p — T phase diagram. The critical pressure where TN → 0 and Tc is maximum equals pc = 1.3 GPa. Here, the resistivity follows ρ(T) α Tn with n = 0.90±0.05 suggesting a local moment-type of quantum critical point. The presence of a maximum structure in the susceptibility and the unusual pressure dependence of Tc hint to an understanding of properties of Ce3PtIn11 in the view of distinct different Kondo screened sublattices. Therefore, we analyze the magnetic entropy Smag within the spin-1/2 Kondo model while accounting for the fact that Ce3PtIn11 unit cell possesses two inequivalent Ce-sites, Ce1 and Ce2. We employ an extreme case scenario of non-interacting sublattices where the Ce1-sublattice is paramagnetic and only Ce2-sublattice orders magnetically and discussed its consequences.

How ground states of quantum matter transform between one another reveals deep insights into the mechanisms stabilizing them. Correspondingly, quantum phase transitions are explored in numerous materials classes, with heavy fermion compounds being among the most prominent ones. Recent studies in an anisotropic heavy fermion compound have shown that different types of transitions are induced by variations of chemical or external pressure [1-3], raising the question of the extent to which heavy fermion quantum criticality is universal. To make progress, it is essential to broaden both the materials basis and the microscopic parameter variety. Here, we identify a cubic heavy fermion material as exhibiting a field-induced quantum phase transition, and show how the material can be used to explore one extreme of the dimensionality axis. The transition between two different ordered phases is accompanied by an abrupt change of Fermi surface, reminiscent of what happens across the field-induced antiferromagnetic to paramagnetic transition in the anisotropic YbRh2Si2. This finding leads to a materials-based global phase diagram -- a precondition for a unified theoretical description., 6 pages, 4 figures

We report a detailed study of the polymorphic transitions in ternary stannide CeRuSn on high quality single crystals through a combination of X-ray diffraction experiments conducted at 300, 275 and 120 K, and measurements of the thermal expansion, magnetization, and resistivity, along main crystallographic axes. In addition, the transition was followed as a function of pressure up to 0.8 GPa. The present X-ray diffraction data show that the room temperature polymorph consists of the lattice doubled along the c axis with respect to the CeCoAl-type structure consistent with previous reports. Upon cooling, the compound undergoes two successive transitions, first to a quintuple (290 K) and than to a triple CeCoAl superstructure at 225 K. The transitions are accompanied by a tremendous volume change due to a strong shrinking of the lattice along the c axis, which is clearly observed in thermal expansion. We advance arguments that the volume collapse originates from an increasing number of crystallographically inequivalent Ce sites and the change of ratio between the short and long Ce-Ru bonds. The observed properties of the polymorphic transition in CeRuSn are reminiscent of the transition in elementary Cerium, suggesting that similar physics, i.e., a Kondo influenced transition and strong lattice vibrations might be the driving forces.

We have investigated the difference in the low-T specific heat, C(T, B), of single- and multi-domain Yb 4 As 3 crystals in magnetic fields B≤4 T. Upon increasing field, which was applied parallel to the trigonal axis, the C(T)/T values of the single-domain sample have been found to be less reduced than that of the multi-domain one. Furthermore, a minimum value of C(T)/T which is unaffected at B≥ 1 T is observed for the single-domain sample around 0.25 K. This behavior cannot be explained by the S = 1/2 Heisenberg antiferromagnet with the intrachain coupling determined by the inelastic neutron scattering. The interchain coupling appears to be responsible for the reported C(T)/T behavior below 1 K.

We present a combined experimental and theoretical study of the structure and the lattice dynamics in the complex metallic alloy Mg(2)Zn(11), by means of neutron and x-ray scattering, as well as ab initio and empirical potential calculations. Mg(2)Zn(11) can be seen as an intermediate step in structural complexity between the simple Laves-phase MgZn(2) on one side, and the complex 1/1 approximants and quasicrystals ZnMgAl and Zn(Mg)Sc on the other. The structure can be described as a cubic packing of a triacontahedron whose center is partially occupied by a Zn atom. This partially occupied site turned out to play a major role in understanding the lattice dynamics. Data from inelastic neutron scattering evidence a Van Hove singularity in the vibrational spectrum of Mg(2)Zn(11) for an energy as low as 4.5 meV, which is a unique feature for a nearly-close-packed metallic alloy. This corresponds to a gap opening at the Brillouin zone boundary and an interaction between a low-lying optical branch and an acoustic one, as could be deduced from the dispersion relation measured by inelastic x-ray scattering. Second, the measured phonon density of states exhibits many maxima, indicating strong mode interactions across the whole energy range. The origin of the low-energy modes in Mg(2)Zn(11) and other features of the vibrational spectra are studied, using both ab initio and empirical potential calculations. A detailed analysis of vibrational eigenmodes is presented, linking features in the vibrational spectrum to atomic motions within structural building blocks.

The heavy fermion compound Ce3Pd20Si6 is one of the rare examples of a cubic system with a readily accessible quantum critical point. Ce atoms at the two different sites 4a and 8c of the crystal structure have recently been shown to have different crystal field ground states (Γ7 and Γ8, respectively) and are assumed to be responsible for the two different low-temperature phase transitions at T(L) and T(U), which have been tentatively attributed to antiferromagnetic and antiferroquadrupolar order, respectively. Here we present electrical resistivity measurements in a wide temperature range (50 mK-300 K) on two new representatives of the La substitution series Ce(3 - x)La(x)Pd20Si6, x=1/3 and 2/3. Put in the context of previously published data our results indicate that La preferentially occupies the 4a site and that Ce ions at the 8c site have a sizably larger Kondo temperature. Low-temperature resistivity measurements in applied magnetic fields suggest that (disorder smeared) quantum critical points exist in the x=1/3 and 2/3 samples at fields below 1 T.

BELGONUCLEAIRE has been operating the Dessel MOX plant at industrial scale between 1986 and 2006. In this period, 40 metric tons of plutonium (HM) has been processed into 90 reloads of MOX fuel for commercial light water reactors. The decision to stop the production in 2006 and to decommission the MOX plant was the result of the shrinkage of the MOX fuel market owing to political and customer’s factors. As a significant part of the decommissioning project of the Dessel MOX plant, about 170 medium-sized glove boxes and about 1.300 metric tons of structure and equipment outside the glove boxes are planned for decommissioning. The license for the decommissioning of the MOX plant was granted by Royal Decree in 2008 and the decommissioning works started in March 2009; the decommissioning works are executed by an integrated organization under leadership and responsibility of BELGONUCLEAIRE with 3 specialized contractors, namely TECNUBEL N.V., the joint venture (THV) BELGOPROCESS / SCK·CEN and STUDSVIK GmbH. In this paper, after having described the main characteristics of the project, the authors introduce the different organisational and technical options considered for the decommissioning of the glove boxes, and the main decision criteria (qualification of personnel and of processes, confinement, cutting techniques & radiation protection, safety aspects, alpha-bearing waste management) are analyzed as well. The progress, the feedback and the lessons learned mid 2011 are presented, giving the principal’s and contractors point of view as well.

We report on the investigation of recently discovered heavy fermion compounds within the Ce-Pd-In system. Single crystals of CenPdmIn3n+2m (n = 2, 3, 5; m = 1, 2) and Ce4Pd10In21 were synthesized from Inux. Speci c heat measurements of the multiphase CenPdmIn3n+2m system revealed a superconducting transition at Tc = 0.69 K arising from Ce2PdIn8 and another, magnetic transition at Tm = 1.67 K arising from either Ce3PdIn11 or Ce5Pd2In19. Low-temperature data of Ce4Pd10In21 display ferromagnetic long-range order below 0.8 K.

We report on low- T ( T ⩾0.02 K) measurements of the electrical resistivity, ρ ( T , B ), and the magnetic AC-susceptibility, χ ac ( T , B ), on the low-carrier density, one-dimensional S= 1 2 antiferromagnet Yb 4 As 3 in magnetic fields B ⩽19 T . For 2 K⩽ T ⩽20 K we find ρ − ρ 0 =AT 2 ( ρ 0 : residual resistivity), with a large coefficient A ≈0.75 μΩ cm/K 2 followed by a minimum around 1 K and a 0.1% increase for T →0. In finite fields and below about 5 K, ρ ( T , B ) shows a history-dependent hysteretic behavior. The oscillatory behavior superimposed is attributed to the Shubnikov–de Haas effect arising from a low density of mobile As–p holes. For T ⩾0.4 K , χ ac ( T ) follows the prediction of the quantum sine-Gordon model. A cusp-like anomaly is found at 0.15 K.

The canonical view of heavy fermion quantum criticality assumes a single quantum critical point separating the paramagnet from the antiferromagnet. However, recent experiments on Yb-based heavy fermion compounds suggest the presence of non-Fermi liquid behavior over a finite zero-temperature region. Using detailed susceptibility and transport measurements we show that the classic quantum critical system, Ge-substituted YbRh2Si2, also displays such behavior. We advance arguments that this is not due to a disorder-smeared quantum critical point, but represents a new class of metallic phase., 4 pages, 4 figures

Single crystals of the type-I clathrate Ba(8)Ni(3.5)Ge(42.1)square(0.4) (space group Pm3n, no. 223, a = 10.798(2) A, l = 30 mm, slashed circle = 8 mm) were grown from the melt using the Bridgman technique. Their composition, determined by microprobe analysis, reveals a distinctly lower Ni content than previously reported for the lower limit (x = 5.4) of the homogeneity range of the clathrate-I phase Ba(8)Ni(x)Ge(46-x). From single crystal X-ray diffraction data we introduce a crystal structure model that takes point defects (vacancies) square in the Ge network into account. It reveals that both Ni and square accumulate at a single site (6c) and that, as a consequence, the Ge network distorts considerably. Ba(8)Ni(3.5)Ge(42.1)square(0.4) shows metal-like behaviour (drho/dT0) albeit with high resistivity at room temperature (rho(300 K) approximately 1 mOmega cm). Together with the low charge carrier concentration of 2.3 e(-)/unit cell at 300 K this is typical of a degenerate semiconductor. The lattice thermal conductivity is distinctly smaller than that of Ba(8)Ge(43)square(3), where the vacancies partially order, and smaller than those of Ba-Ni-Ge type-I clathrates without vacancies, suggesting that disordered vacancies efficiently scatter heat-transporting phonons. We provide evidence that the maximum value of the thermoelectric figure of merit reached in Ba(8)Ni(3.5)Ge(42.1)square(0.4), ZT(680 K) congruent with 0.21, can be further improved by adjusting the charge carrier concentration.

To elucidate the discrepancies in low-temperature data reported on the quantum critical heavy fermion compound ${\text{Ce}}_{3}{\text{Pd}}_{20}{\text{Si}}_{6}$ and reveal the compound's intrinsic properties, single crystals of varying stoichiometry were grown by various techniques---from the melt and from high-temperature solutions using fluxes of various compositions. The resulting stoichiometry of the crystals as well as their physical properties show sizable dependence on the different growth techniques. The Ce content $\ensuremath{\Delta}\text{Ce}$ varies by more than $3\text{ }\text{at}\text{.}\text{ }%$ among all grown single crystals. We have revealed a systematic dependence of the residual resistance ratio, the lattice parameter, the (lower) phase-transition temperature ${T}_{L}$, and the maximum in the temperature dependent electrical resistivity ${T}_{max}$ with $\ensuremath{\Delta}\text{Ce}$. This clarifies the sizable variation in the values of ${T}_{L}$ reported in the literature. We discuss the physical origin of the observed composition-property relationship in terms of a Kondo lattice picture. We predict that a modest pressure can suppress ${T}_{L}$ to zero and thus induce a quantum critical point.

A 67-year-old man was admitted to the hospital with symptoms of progressive dyspnoea. For 2 months he had received second-line treatment with dexamethasone and thalidomide for a multiple myeloma. Physical examination revealed a tachypnoeic patient and arterial blood gas analysis revealed a respiratory alkalosis and severe hypoxaemia. A high-resolution CT scan showed diffuse ground glass opacities in both lungs. Pulmonary function testing indicated severe diffusion capacity impairment. Bronchoalveolar lavage and cultures excluded the possibility of an infectious agent. The thalidomide treatment was discontinued whereupon the hypoxaemia and the ground glass opacities resolved and the diffusion capacity impairment improved. When a patient treated with thalidomide presents with dyspnoea and hypoxaemia with ground glass opacities, thalidomide-induced pneumonitis should be considered. Withdrawing thalidomide is the only treatment.

Each clinical encounter represents an amazing series of psychological events: perceiving the features of the situation; quickly accessing relevant hypotheses; checking for signs and symptoms that confirm or rule out competing hypotheses, and using related knowledge to guide appropriate investigations and treatment.Script theory, issued from cognitive psychology, provides explanations of how these events are mentally processed. This essay is aimed at clinical teachers who are interested in basic sciences of education. It describes the script concept and how it applies in medicine via the concept of the 'illness script'.Script theory asserts that, to give meaning to a new situation in our environment, we use goal-directed knowledge structures adapted to perform tasks efficiently. These integrated networks of prior knowledge lead to expectations, as well as to inferences and actions. Expectations and actions embedded in scripts allow subjects to make predictions about features that may or may not be encountered in a situation, to check these features in order to adequately interpret (classify) the situation, and to act appropriately.Theory raises questions about how illness scripts develop and are refined with clinical experience. It also provides a framework to assist their acquisition.

We report a comprehensive study of CeIn$_{3-x}$Sn$_x$ $(0.55 \leq x \leq 0.8)$ single crystals close to the antiferromagnetic (AF) quantum critical point (QCP) at $x_c\approx 0.67$ by means of the low-temperature thermal expansion and Gr\"uneisen parameter. This system represents the first example for a {\it cubic} heavy fermion (HF) in which $T_{\rm N}$ can be suppressed {\it continuously} down to T=0. A characteristic sign change of the Gr\"uneisen parameter between the AF and paramagnetic state indicates the accumulation of entropy close to the QCP. The observed quantum critical behavior is compatible with the predictions of the itinerant theory for three-dimensional critical spinfluctuations. This has important implications for the role of the dimensionality in HF QCPs., Comment: Physical Review Letters, to be published