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Junctions and interfaces consisting of unconventional superconductors provide an excellent experimental playground to study exotic phenomena related to the phase of the order parameter. Not only does the complex structure of unconventional order parameters have an impact on the Josephson effects, but it also may profoundly alter the quasiparticle excitation spectrum near a junction. Here, by using spectroscopic-imaging scanning tunneling microscopy, we visualize the spatial evolution of the LDOS near twin boundaries (TBs) of the nodal superconductor FeSe. The π/2 rotation of the crystallographic orientation across the TB twists the structure of the unconventional order parameter, which may, in principle, bring about a zero-energy LDOS peak at the TB. The LDOS at the TB observed in our study, in contrast, does not exhibit any signature of a zero-energy peak, and an apparent gap amplitude remains finite all the way across the TB. The low-energy quasiparticle excitations associated with the gap nodes are affected by the TB over a distance more than an order of magnitude larger than the coherence length ξab . The modification of the low-energy states is even more prominent in the region between two neighboring TBs separated by a distance ≈7ξab . In this region, the spectral weight near the Fermi level (≈±0.2meV ) due to the nodal quasiparticle spectrum is almost completely removed. These behaviors suggest that the TB induces a fully gapped state, invoking a possible twist of the order parameter structure, which breaks time-reversal symmetry.

Spontaneous symmetry breaking is an important concept in many branches of physics. In helium-3 (³He), the breaking of symmetry leads to the orbital chirality in the superfluid phase known as ³He-A. Chirality is a fundamental property of ³He-A, but its direct detection has been challenging. We report direct detection of chirality by transport measurements of electrons trapped below a free surface of ³He-A. In particular, we observed the so-called intrinsic Magnus force experienced by a moving electron; the direction of the force directly reflected the chirality. We further showed that, at the superfluid transition, the system selected either right-or left-handed chirality. The observation of such selection directly demonstrates chiral symmetry breaking.

The coupling of spin angular momentum and mechanical rotation is utilized for generating a spin current of nuclear spins of the liquid helium-3. A hydrodynamic flow in the liquid helium-3 provides a vorticity gradient which can be regarded as a gradient of effective magnetic field by the spin-rotation coupling. The effective field gradient generates a nuclear spin current owing to the Stern–Gerlach effect. We quantitatively estimate the magnitude of the field gradient based on the microscopic Boltzmann equation. The effective field gradient is large enough to be detected by NMR measurements.

PurposeIn human oocytes, sERCs are one of the dysmorphic phenotypes that have been reported. Significantly reduced pregnancy rates and a comparatively higher number of abnormities in live births appear to be associated with the presence of sERCs in oocytes. However, some reports have shown that healthy babies can be born, without any reduced pregnancy rates, from oocytes observed to contain sERCs. Thus, the clinical and scientific significance of oocytes that harbor sERCs remains controversial.MethodsThe presence of sERCs was evaluated using a time-lapse system while studying the dynamic changes within oocytes and embryos. Logistic regression analysis was carried out to explore the independent variables for meiotic and mitotic cleavage failure..ResultsThe incidence of mitotic cleavage failure and the incidence of meiotic cleavage failure during the second polar body extrusion in oocytes with sERCs were found to be significantly higher than that in oocytes without sERCs. Furthermore, ICSI was found to have a greater frequency of meiotic failure than IVF.ConclusionsIn cases of cleavage failure, an embryonic cell could become tetraploid and may induce abnormal chromosomal configurations. Some cells exposed to cleavage failure may become trophectoderm cells and form placental abnormalities. Even if they develop into trophectoderm cells, the ICM can be susceptible to further cleavage failure and may in turn cause further aneuploidy. For these reasons, it is important to monitor pregnancies and births derived from oocytes that contained sERCs.

A Ti-6Al-7Nb alloy with three different initial microstructures was processed by high-pressure torsion (HPT) and the resultant microstructure and mechanical properties of the alloy after HPT processing were investigated. The microstructure of the as-received alloy was an equiaxed (α+β) microstructure. The rods were subjected to solution treatment and aging (STA) treatment to obtain a bi-modal microstructure consisting of an equiaxed α phase and lamellar α+β phases, and those to solution treatment and quenching (STQ) treatment to obtain a bi-modal microstructure consisting of equiaxed α-phase and acicular α’-phase. Disks were cut from those rods and were processed by HPT under a pressure of 6 GPa. After HPT processing through 20 revolutions, the alloy with each of the three initial microstructures showed ultrafine grains with a size of ~70 nm. The alloy resulted in a higher tensile strength (1350 MPa) in both the bi-modal microstructures than that (1250 MPa) in the alloy with equiaxed α+β microstructure after HPT processing. It was shown that the Ti-6Al-7Nb alloy with the bi-modal microstructure was strengthened more than with the equiaxed α+β microstructure when the alloy was processed by HPT. Furthermore, the alloy with bi-modal microstructure consisting of equiaxed α-phase and acicular α’-phase showed a good balance between the tensile strength (1280 MPa) and the elongation to fracture (22%) after HPT processing through 1 revolution. In summary, therefore, large strength and elongation of the Ti-6Al-7Nb alloy were simultaneously achieved by HPT processing.

Background and purpose: Protein transduction domains (PTDs), such as Tat, antennapedia homeoprotein (Antp), Rev and VP22, have been extensively utilized for intracellular delivery of biologically active macromolecules in vitro and in vivo. There is little known, however, about the relative transduction efficacy, cytotoxicity and internalization mechanism of individual PTDs. Experimental approach: We examined the cargo delivery efficacies of four major PTDs (Tat, Antp, Rev and VP22) and evaluated their toxicities and cell internalizing pathways in various cell lines. Key results: The relative order of the transduction efficacy of these PTDs conjugated to fluorescein was Rev>Antp>Tat>VP22, independent of cell type (HeLa, HaCaT, A431, Jurkat, MOLT‐4 and HL60 cells). Antp produced significant toxicity in HeLa and Jurkat cells, and Rev produced significant toxicity in Jurkat cells. Flow cytometric analysis demonstrated that the uptake of PTD–fluorescein conjugate was dose‐dependently inhibited by methyl‐β‐cyclodextrin, cytochalasin D and amiloride, indicating that all four PTDs were internalized by the macropinocytotic pathway. Accordingly, in cells co‐treated with ‘Tat‐fused’ endosome‐disruptive HA2 peptides (HA2‐Tat) and independent PTD‐fluorescent protein conjugates, fluorescence spread throughout the cytosol, indicating that all four PTDs were internalized into the same vesicles as Tat. Conclusions and implications: These findings suggest that macropinocytosis‐dependent internalization is a crucial step in PTD‐mediated molecular transduction. From the viewpoint of developing effective and safe protein transduction technology, although Tat was the most versatile carrier among the peptides studied, PTDs should be selected based on their individual characteristics. British Journal of Pharmacology (2008) 153, 1143–1152; doi:10.1038/sj.bjp.0707678; published online 28 January 2008

Half-integer spin quadrupolar nuclei are the only magnetic isotopes for the majority of the chemical elements. Therefore, the transfer of polarization from protons to these isotopes under magic-angle spinning (MAS) can provide precious insights into the interatomic proximities in hydrogen-containing solids, including organic, hybrid, nanostructured and biological solids. This transfer has recently been combined with dynamic nuclear polarization (DNP) in order to enhance the NMR signal of half-integer quadrupolar isotopes. However, the cross-polarization transfer lacks robustness in the case of quadrupolar nuclei, and we have recently introduced as an alternative technique a D-RINEPT (through-space refocused insensitive nuclei enhancement by polarization transfer) scheme combining a heteronuclear dipolar recoupling built from adiabatic pulses and a continuous-wave decoupling. This technique has been demonstrated at 9.4 T with moderate MAS frequencies, νR≈10–15 kHz, in order to transfer the DNP-enhanced 1H polarization to quadrupolar nuclei. Nevertheless, polarization transfers from protons to quadrupolar nuclei are also required at higher MAS frequencies in order to improve the 1H resolution. We investigate here how this transfer can be achieved at νR≈20 and 60 kHz. We demonstrate that the D-RINEPT sequence using adiabatic pulses still produces efficient and robust transfers but requires large radio-frequency (rf) fields, which may not be compatible with the specifications of most MAS probes. As an alternative, we introduce robust and efficient variants of the D-RINEPT and PRESTO (phase-shifted recoupling effects a smooth transfer of order) sequences using symmetry-based recoupling schemes built from single and composite π pulses. Their performances are compared using the average Hamiltonian theory and experiments at B0=18.8 T on γ-alumina and isopropylamine-templated microporous aluminophosphate (AlPO4-14), featuring low and significant 1H–1H dipolar interactions, respectively. These experiments demonstrate that the 1H magnetization can be efficiently transferred to 27Al nuclei using D-RINEPT with SR412(270090180) recoupling and using PRESTO with R2227(1800) or R1676(270090180) schemes at νR=20 or 62.5 kHz, respectively. The D-RINEPT and PRESTO recoupling schemes complement each other since the latter is affected by dipolar truncation, whereas the former is not. We also analyze the losses during these recoupling schemes, and we show how these magnetization transfers can be used at νR=62.5 kHz to acquire in 72 min 2D HETCOR (heteronuclear correlation) spectra between 1H and quadrupolar nuclei, with a non-uniform sampling (NUS).

The water supply must be safe and sustainable. This requires a regulatory compliance, selection of an optimal water treatment process, timely response to water quality incidents as well as maintaining internal skills and knowledge among utility personnel to keep appropriate operational standards in the long run. Water supply services in Japan face various challenges, including a shrinking revenue base due to a declining population as well as a mass retirement of the baby-boomer generation. The Japan Water Research Center conducted questionnaire surveys and based on our findings developed the ‘knowledge transfer support system for water treatment technology’ for utilities to maintain internal skills and knowledge in the face of shrinking labour forces in the water sector. The system consists of three components: the database on water treatment technology, learning program on water treatment technology, and the assessment tool for knowledge transfer on water treatment technology.

Background: Recently, the vitamin D receptor (VDR) polymorphism Fok I was shown to be associated with susceptibility to ovarian cancer. We aimed to examine whether VDR Fok I polymorphisms influence the survivals of patients with epithelial ovarian cancer (EOC). Methods: VDR polymorphisms from Fok I in 101 patients with EOC were genotyped by sequencing. Overall survival was compared between Fok I single nucleotide polymorphism using Kaplan–Meier survival curves with log-rank tests and the Cox proportional hazard model adjusted for ages, stages, histology, and existence of residual tumour. Results: The Fok I C/C genotypes were associated with better prognosis compared with the C/T and T/T genotypes (log-rank test: P =0.008; adjusted hazard ratio, 0.18; 95%CI 0.05–0.61; P =0.006). Conclusions: These results suggest that the VDR polymorphisms from the Fok I genotype may be associated with improved prognosis of patients with EOC.

Although they are well documented in autopsy series, the macroscopic features and associated anomalies of schizencephalies have not been described in detail in a large clinical population. To assess the macroscopic findings of schizencephaly and the prevalence of associated findings, we conducted a retrospective MR analysis of a group of patients with schizencephaly. The MR studies of 35 patients with schizencephaly were retrospectively reviewed. The images were examined for the location and size of the schizencephalic cleft, the presence and location of associated polymicrogyria, and the presence, location, and severity of other brain anomalies. A total of 54 schizencephalic clefts were seen in the 35 patients. These clefts were unilateral in 18 (51%) patients and bilateral in 17 (49%) patients; three clefts were identified in two patients. Nine clefts (17%) had fused lips and 45 had separated-lip clefts (83%). Polymicrogyria was present inside 23 clefts (43%), while subependymal heterotopias were present at the cleft orifice in 27 clefts (50%). Polymicrogyria was identified outside the cleft, both adjacent to and remote from the cleft, in 23 patients (66%). Abnormal cerebral white-matter signal intensity was present in seven patients (20%), while white-matter volume diminution was noted in all patients. Ventricular diverticula with mass effect, roofing membranes, remnant floors, and cord-like remnants were present in 12, 1, 11, and 3 patients, respectively. Our results show that the spectrum of macroscopic findings in schizencephaly includes fused-lip and separated-lip clefts, polymicrogyric and non-polymicrogyric cleft linings, cyst-like diverticula and membranous structures, and subependymal heterotopia at the cleft. Concomitant anomalies are polymicrogyria outside the cleft, white-matter diminution, septal and optic pathway anomalies, callosal anomalies and hippocampal anomalies. Unilateral and bilateral clefts occur in a nearly equal frequency in the clinical population, in contrast to the high incidence of bilateral schizencephaly reported in the pathological literature.