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Heat pumps based on magnetocaloric and electrocaloric working bodies—in which entropic phase transitions are driven by changes of magnetic and electric field, respectively—use displaceable fluids to establish relatively large temperature spans between loads to be cooled and heat sinks 1 , 2 . However, the performance of prototypes is limited because practical magnetocaloric working bodies driven by permanent magnets 3 – 5 and electrocaloric working bodies driven by voltage 6 – 16 display temperature changes of less than 3 kelvin. Here we show that high-quality multilayer capacitors of PbSc 0.5 Ta 0.5 O 3 display large electrocaloric effects over a wide range of starting temperatures when the first-order ferroelectric phase transition is driven supercritically (as verified by Landau theory) above the Curie temperature of 290 kelvin by electric fields of 29.0 volts per micrometre. Changes of temperature in the large central area of the capacitor peak at 5.5 kelvin near room temperature and exceed 3 kelvin for starting temperatures that span 176 kelvin (complete thermalization would reduce these values from 5.5 to 3.3 kelvin and from 176 to 73 kelvin). If magnetocaloric working bodies were to be replaced with multilayer capacitors of PbSc 0.5 Ta 0.5 O 3 , then the established design principles behind magnetocaloric heat pumps could be repurposed for better performance without bulky and expensive permanent magnets. High-quality multilayer capacitors of a perovskite oxide show that large electric-field-driven caloric effects could improve solid-state refrigeration technology and challenge today’s standard (based on magnetocaloric effects in gadolinium).

Ferroaxial materials that exhibit spontaneous ordering of a rotational structural distortion with an axial vector symmetry have gained growing interest, motivated by recent extensive studies on ferroic materials. As in conventional ferroics (e.g., ferroelectrics and ferromagnetics), domain states will be present in the ferroaxial materials. However, the observation of ferroaxial domains is non-trivial due to the nature of the order parameter, which is invariant under both time-reversal and space-inversion operations. Here we propose that NiTiO 3 is an order-disorder type ferroaxial material, and spatially resolve its ferroaxial domains by using linear electrogyration effect: optical rotation in proportion to an applied electric field. To detect small signals of electrogyration (order of 10 −5  deg V −1 ), we adopt a recently developed difference image-sensing technique. Furthermore, the ferroaxial domains are confirmed on nano-scale spatial resolution with a combined use of scanning transmission electron microscopy and convergent-beam electron diffraction. Our success of the domain visualization will promote the study of ferroaxial materials as a new ferroic state of matter. The presence of ferroaxial domain states is recently experimentally demonstrated by a nonlinear optical technique, which lacks high spatial resolution to visualize ferroaxial domains. Here, the authors visualize spatial distributions of ferroaxial domains in NiTiO 3 showing an order-disorder type ferroaxial transition.

In juvenile myoclonic epilepsy, data are limited on the genetic basis of networks promoting convulsions with diffuse polyspikes on electroencephalography (EEG) and the subtle microscopic brain dysplasia called microdysgenesis. Using Sanger sequencing, we sequenced the exomes of six members of a large family affected with juvenile myoclonic epilepsy and confirmed cosegregation in all 37 family members. We screened an additional 310 patients with this disorder for variants on DNA melting-curve analysis and targeted real-time DNA sequencing of the gene encoding intestinal-cell kinase ( ICK). We calculated Bayesian logarithm of the odds (LOD) scores for cosegregating variants, odds ratios in case-control associations, and allele frequencies in the Genome Aggregation Database. We performed functional tests of the effects of variants on mitosis, apoptosis, and radial neuroblast migration in vitro and conducted video-EEG studies in mice lacking a copy of Ick. A variant, K305T (c.914A→C), cosegregated with epilepsy or polyspikes on EEG in 12 members of the family affected with juvenile myoclonic epilepsy. We identified 21 pathogenic ICK variants in 22 of 310 additional patients (7%). Four strongly linked variants (K220E, K305T, A615T, and R632X) impaired mitosis, cell-cycle exit, and radial neuroblast migration while promoting apoptosis. Tonic-clonic convulsions and polyspikes on EEG resembling seizures in human juvenile myoclonic epilepsy occurred more often in knockout heterozygous mice than in wild-type mice (P=0.02) during light sleep with isoflurane anesthesia. Our data provide evidence that heterozygous variants in ICK caused juvenile myoclonic epilepsy in 7% of the patients included in our analysis. Variant ICK affects cell processes that help explain microdysgenesis and polyspike networks observed on EEG in juvenile myoclonic epilepsy. (Funded by the National Institutes of Health and others.).

Heat generation is one of the significant problems in piezoelectrics for high power density applications. In this paper, we review the loss mechanisms in piezoelectrics first, followed by the heat generation processes for various drive conditions. Heat generation at off-resonance is caused mainly by dielectric loss tan δ′ (i.e., P-E hysteresis loss), not by mechanical loss, while the heat generation at resonance is mainly attributed to mechanical loss tan φ′. Then, practical high power materials developed at Penn State is introduced, which exhibit the vibration velocity more than 1 m/s, leading to the power density capability 10 times of the commercially available “hard” PZTs. We propose a internal bias field model to explain the low loss and high power origin of these materials. Finally, using a low temperature sinterable “hard” PZT, we demonstrated a high power multilayer piezoelectric transformers.

Boundary integral equations are formulated to investigate nonlinear waves generated by a debonding interface of bi-material subjected to an incident plane wave. For the numerical simulation, the IRK (Implicit Runge-Kutta method) based CQ-BEM (Convolution Quadrature-Boundary Element Method) is developed. The interface conditions for a debonding area, consisting of three phases of separation, stick, and slip, are developed for the simulation of nonlinear ultrasonic waves. Numerical results are obtained and discussed for normal incidence of a plane longitudinal wave onto the nonlinear interface with a static compressive stress.

BackgroundThe inhibitory FcγRIIb-deficient mice develop autoimmune diseases, such as lupus nephritis, rheumatoid arthritis, and vasculitis with inflammatory cell infiltration [1,2]; however, the incorporation of FcγRIIb-linked autoimmune-prone SLAM haplotype in these gene targeting mice makes it difficult to isolate the role of FcγRIIb deficiency from SLAM haplotype in these diseases.ObjectivesIn the present study, we genetically dissected the role of FcγRIIb deficiency and SLAM haplotype for these autoimmune diseases.MethodsBy extensively backcrossing 129-based FcγRIIb-deficient mice to B6 mice, three congenic mouse strains were established, the first with FcγRIIb deficiency and 129-derive autoimmune-prone SLAM haplotype (KO1), the second with FcγRIIb deficiency and B6 SLAM haplotype (KO2), and the third with wild-type FcγRIIb and 129 SLAM haplotype (SLAM129).ResultsLupus nephritis did not develop in KO1, KO2, and SLAM129; however, KO1 and SLAM129 showed age-associated monocytosis and perivascular inflammatory cell infiltration. When introducing Yaa mutation, KO1.Yaa and KO2.Yaa mice developed severe nephritis. In contrast, SLAM129.Yaa mice developed mild form of lupus nephritis with the increased serum level of IgM, but not IgG, class autoantibodies.ConclusionsMonocytosis was shown to be one of the characteristic features in murine models of lupus nephritis [3]. Our study suggests that autoimmune-prone SLAM haplotype plays a pivotal role for monocytosis and resulting perivascular inflammatory cell infiltration; however, SLAM129 alone is not enough for the development of lupus nephritis. FcγRIIb deficiency alone was not enough for both monocytosis and lupus nephritis. In the presence of Yaa, FcγRIIb deficiency plays a significant role for the development of lupus nephritis with isotype switch of autoantibodies from IgM to pathogenic IgG class. Mild form of lupus nephritis in SLAM129.Yaa mice may be due to the deposition of IgM autoantibodies in glomeruli, which results in the up-regulation of chemokine production by activated mesangial cells and resultant inflammatory cell infiltration to glomeruli because of the high frequencies of monocytes in periphery.ReferencesBollans S. and Ravetch JV. Immunity 13:277-285, 2000.Sato-Hayashizaki A, et al. Arthritis Rheum. 63:2930-2938, 2011.Wofsy D, et al. J. Exp. Med. 159:629-634, 1984.Disclosure of InterestNone declared

Rice glutelin is synthesized as a precursor in the endosperm endoplasmic reticulum and then deposited within the protein storage vacuole protein body-II (PB-II) as an aggregate, with a high degree of polymerized higher-order structure comprising mature acidic and basic subunits after post-translation processing cleavage. In order to investigate the functional role of this processing and its effect on folding assembly, wild-type GluA2 and its mutant cDNA (mGluA2), in which the conserved processing site (Asn-Gly) at the junction between the acidic and basic chains was replaced with Ala-Ala, were expressed under the control of the endosperm-specific GluB1 promoter in the mutant rice a123 line lacking glutelin GluA1, GluA2, and GluB4. The mGluA2 precursor was synthesized and stably targeted to PB-II without processing in the transgenic rice seeds like the wild-type GluA2. Notably, the saline-soluble mGluA2 precursor assembled with the other type of processed glutelin GluB as a trimer in PB-II, although such hetero-assembly with GluB was not detected in the transformant containing the processed GluA. Furthermore, the mGluA2 precursor in the glutelin fraction was deposited in PB-II by forming a quite different complex from the processed mature GluA2 products. These results indicate that post-translational processing of glutelin is not necessary for trafficking and stable accumulation in PB-II, but is required for the formation of the higher-order structure required for stacking in PB-II.

Background FcγRIIB negatively regulates BCR-mediated activation signals. We previously established an FcγRIIB-deficient B6-congenic mouse strain (KO1) by gene targeting in 129-derived embryonic stem cells followed by backcrossing to B6 mice. KO1 spontaneously developed pathology of rheumatoid arthritis (RA) with autoantibody production and pannus formation leading to joint destruction. Objectives To analyse the phenotypic change of KO1 by crossing with lupus prone New Zealand White (NZW) mice, we established the F1 hybrid of KO1 and NZW mice. Also we analysed (KO1 x NZW) F2 mice to see the sharing loci contributing to disease phenotypes. Methods We analysed the (KO1 x NZW) F1 mice and (KO1 x NZW) F2 mice. Serum levels of RF, IgG antibodies against double-stranded DNA and chromatin were measured using ELISA. The severity of renal disease was monitored by biweekly testing for proteinuria. Histopathological examination was also performed. Results The F1 hybrid of these mice developed glomerulonephritis with the high incidence of positive anti- double-stranded DNA and chromatin antibodies. They did not develop the phenotype of RA, but developed lupus phenotype associated with the inflammatory infiltration in salivary glands as observed in Sjögren syndrome. In the progeny of (KO1 x NZW) F2 mice, RA, SLE, and Sjögren syndrome developed independently or overlapped in an individual mouse. We found that the B6-derived locus located in the centromeric region on chromosome 12 was significantly associated with all these disease phenotypes, suggesting that this locus may play a role in common process shared by these diseases. Conclusions Phenotypic specificity of murine autoimmune disorder depends on the genetic factors sharing RA, SLE, and Sjögren syndrome. Disclosure of Interest None declared DOI 10.1136/annrheumdis-2014-eular.6071

Transient elastodynamic crack analysis in two-dimensional (2D), layered, anisotropic and linear elastic solids is presented in this paper. A time-domain boundary element method (BEM) in conjunction with a multi-domain technique is developed for this purpose. Time-domain elastodynamic fundamental solutions for homogenous, anisotropic and linear elastic solids are applied in the present time-domain BEM. The spatial discretization of the boundary integral equations is performed by a Galerkin-method, while a collocation method is adopted for the temporal discretization of the arising convolution integrals. An explicit time-stepping scheme is developed to compute the unknown boundary data and the crack-opening-displacements (CODs). To show the effects of the crack configuration, the material anisotropy, the layer combination and the dynamic loading on the dynamic stress intensity factors and the scattered elastic wave fields, several numerical examples are presented and discussed.

. Beam helicity asymmetries in the e → p → e K + Λ reaction have been measured at unprecedentedly low four-momentum transfers 〈 Q 2 〉 = 0 . 05 ( GeV / c ) 2 . At the Mainz Microtron (MAMI), the experiment was performed with a longitudinally polarized beam and an out-of-plane detection of the scattered electron. This experiment probed the associated helicity-dependent structure function d σ L T / d Ω K c . m . , which is sensitive to the details of resonances of the proton. The results were compared to models for kaon electroproduction using effective Lagrangians. The MAMI data is not supporting the Kaon-Maid isobar model, which uses strong longitudinal couplings of the virtual photon to nucleon resonances and predicts a strong peaking of the structure function at forward angles and low Q 2 . The data is also in disagreement with a Regge-plus-resonance model that predicts the incorrect sign of the structure function. The combination of the MAMI results wih data taken at higher four-momentum transfers measured at Jefferson Lab indicates a smooth transition in Q 2 without significant changes of the interference pattern in the electroproduction process.