Enhanced charge density wave with mobile superconducting vortices in La1.885Sr0.115CuO4.

Superconductivity in the cuprates is found to be intertwined with charge and spin density waves. Determining the interactions between the different types of order is crucial for understanding these important materials. Here, we elucidate the role of the charge density wave (CDW) in the prototypical cuprate La1.885Sr0.115CuO4, by studying the effects of large magnetic fields (H) up to 24 Tesla. At low temperatures (T), the observed CDW peaks reveal two distinct regions in the material: a majority phase with short-range CDW coexisting with superconductivity, and a minority phase with longer-range CDW coexisting with static spin density wave (SDW). With increasing magnetic field, the CDW first grows smoothly in a manner similar to the SDW. However, at high fields we discover a sudden increase in the CDW amplitude upon entering the vortex-liquid state. Our results signify strong coupling of the CDW to mobile superconducting vortices and link enhanced CDW amplitude with local superconducting pairing across the H - T phase diagram.

Two-Dimensional Superconducting Fluctuations Associated with Charge-Density-Wave Stripes in La_{1.87}Sr_{0.13}Cu_{0.99}Fe_{0.01}O_{4}.

The presence of a small concentration of in-plane Fe dopants in La_{1.87}Sr_{0.13}Cu_{0.99}Fe_{0.01}O_{4} is known to enhance stripelike spin and charge density wave (SDW and CDW) order and suppress the superconducting T_{c}. Here, we show that it also induces highly two-dimensional superconducting correlations that have been argued to be the signatures of a new form of superconducting order, the so-called pair density wave (PDW) order. In addition, using resonant soft x-ray scattering, we find that the two-dimensional superconducting fluctuation is strongly associated with the CDW stripe. In particular, the PDW signature first appears when the correlation length of the CDW stripe grows over eight times the lattice unit (∼8a). These results provide critical conditions for the formation of the PDW order.

Examining the association between serum free fatty acids and blood levels of testosterone.

BACKGROUND: Multiple studies have uncovered the effects that ingested fat has on human blood levels of testosterone. Yet, few reports have discussed the effect of circulating serum free fatty acids (FFAs). The present study aimed to explore the relationship between serum free fatty acids and blood levels of testosterone. METHODS: In total, 5719 adults were pooled from the database of the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2012. Based on multivariable-linear regression models, we employed a total of 30 FFAs to interpret the relationship of FFAs with blood levels of testosterone. Two models with covariate adjustments were designated for further evaluation and analysis. RESULTS: Capric acid [ß = -0.014, 95% confidence interval (CI) = -0.023, -0.004, P = 0.005], myristic acid (ß = -0.001, 95% CI = -0.001, 0.000, P ≤ 0.001), pentadecanoic acid (ß = -0.013, 95% CI = -0.018, -0.008, P ≤ 0.001), margaric acid (ß = -0.011, 95% CI = -0.017, -0.005, P ≤ 0.001) and alpha-linolenic acid (ß = -0.001, 95% CI = -0.002, 0.000, P = 0.004) in the fully adjusted model were significantly negatively correlated with the testosterone level inh obese men. In the fully adjusted model for the female analysis, myristic acid, pentadecanoic acid, palmitic acid, margaric acid, stearic acid, myristoleic acid, oleic acid, nervonic acid and alpha-linolenic acid were found significantly associated with the testosterone level. CONCLUSIONS: Our findings indicate a significant negative correlation between serum FFAs and blood levels of testosterone. Furthermore, we reveal the essentiality of serum FFAs and their potential effects on the reduction of testosterone levels.

Subnanosecond phase transition dynamics in laser-shocked iron.

Iron is one of the most studied chemical elements due to its sociotechnological and planetary importance; hence, understanding its structural transition dynamics is of vital interest. By combining a short pulse optical laser and an ultrashort free electron laser pulse, we have observed the subnanosecond structural dynamics of iron from high-quality x-ray diffraction data measured at 50-ps intervals up to 2500 ps. We unequivocally identify a three-wave structure during the initial compression and a two-wave structure during the decaying shock, involving all of the known structural types of iron (α-, γ-, and ε-phase). In the final stage, negative lattice pressures are generated by the propagation of rarefaction waves, leading to the formation of expanded phases and the recovery of γ-phase. Our observations demonstrate the unique capability of measuring the atomistic evolution during the entire lattice compression and release processes at unprecedented time and strain rate.

Pectoralis muscle area is associated with bone mineral density and lung function in lung transplant candidates.

Loss of bone mineral density and skeletal muscle area are linked in lung transplant patients. This loss is greater in patients with restrictive compared with obstructive lung diseases. INTRODUCTION: Sarcopenia and osteoporosis are associated with aging and chronic illnesses and may be linked in patients with advanced lung disease. Pectoralis muscle index (PMI) quantitated on computed tomography (CT) of the chest can be used to measure skeletal muscle mass. This study aimed to determine the relationship of PMI to clinical parameters including bone mineral density (BMD) in candidates for lung transplantation. METHODS: A retrospective review of transplant candidates at a single center was performed. Demographic, anthropomorphic, and clinical data were recorded. Pectoralis muscle area (PMA) was determined on an axial slice from a chest CT. PMI was calculated as the PMA divided by height squared. BMD was obtained from routine dual-energy X-ray absorptiometry (DXA) scan. RESULTS: In 226 included patients, mean PMI was 8.2 ± 3.0 cm2/m2 in males and 6.1 ± 2.1 cm2/m2 in females. Osteopenia was present in 44.4%, and 23.2% of patients had osteoporosis. Patients with obstructive lung disease had lower body mass index (22.0 ± 4.9 versus 27.9 ± 4.9 kg/m2, p < 0.001), PMI (6.0 ± 2.3 versus 8.2 ± 2.8 cm2/m2, p < 0.001), and BMD (- 2.3 ± 1.1 versus - 1.3 ± 1.1, p < 0.001) compared with patients with restrictive lung disease. PMI was a significant predictor of BMD (ß = 0.16, p < 0.001). CONCLUSION: The association between muscle area and BMD in lung transplant candidates suggests that similar mechanisms may underlie the development of both. Differences in PMI and BMD in patients with obstructive versus restrictive lung disease may result from differences in respiratory physiology or disease processes.

Observation of two types of charge-density-wave orders in superconducting La2-xSrxCuO4.

The discovery of charge- and spin-density-wave (CDW/SDW) orders in superconducting cuprates has altered our perspective on the nature of high-temperature superconductivity (SC). However, it has proven difficult to fully elucidate the relationship between the density wave orders and SC. Here, using resonant soft X-ray scattering, we study the archetypal cuprate La2-xSrxCuO4 (LSCO) over a broad doping range. We reveal the existence of two types of CDW orders in LSCO, namely CDW stripe order and CDW short-range order (SRO). While the CDW-SRO is suppressed by SC, it is partially transformed into the CDW stripe order with developing SDW stripe order near the superconducting Tc. These findings indicate that the stripe orders and SC are inhomogeneously distributed in the superconducting CuO2 planes of LSCO. This further suggests a new perspective on the putative pair-density-wave order that coexists with SC, SDW, and CDW orders.

Ideal charge-density-wave order in the high-field state of superconducting YBCO.

The existence of charge-density-wave (CDW) correlations in cuprate superconductors has now been established. However, the nature of the CDW ground state has remained uncertain because disorder and the presence of superconductivity typically limit the CDW correlation lengths to only a dozen unit cells or less. Here we explore the field-induced 3D CDW correlations in extremely pure detwinned crystals of YBa2Cu3O2 (YBCO) ortho-II and ortho-VIII at magnetic fields in excess of the resistive upper critical field ([Formula: see text]) where superconductivity is heavily suppressed. We observe that the 3D CDW is unidirectional and possesses a long in-plane correlation length as well as significant correlations between neighboring CuO2 planes. It is significant that we observe only a single sharply defined transition at a critical field proportional to [Formula: see text], given that the field range used in this investigation overlaps with other high-field experiments including quantum oscillation measurements. The correlation volume is at least two to three orders of magnitude larger than that of the zero-field CDW. This is by far the largest CDW correlation volume observed in any cuprate crystal and so is presumably representative of the high-field ground state of an "ideal" disorder-free cuprate.

Observation of Orbital Order in the Half-Filled 4f Gd Compound.

Half-filled electron systems, even with the maximized spin angular moment, have been given little attention because of their zero-orbital angular moment according to Hund's rule. Nevertheless, there are several measurements that show evidence of a nonzero orbital moment as well as spin-orbit coupling. Here we report for the first time the orbital order in a half-filled 4f-electron system GdB_{4}, using the resonant soft x-ray scattering at Gd M_{4,5}-edges. Furthermore, we discovered that the development of this orbital order is strongly coupled with the antiferromagnetic spin order. These results clearly demonstrate that even in half-filled electron systems the orbital angular moment can be an important parameter to describe material properties, and may provide significant opportunities for tailoring new correlated electron systems.

Impact of mTOR Inhibitors on Cancer Development in Kidney Transplantation Recipients: A Population-Based Study.

BACKGROUND: The mammalian target of rapamycin (mTOR) inhibitor is an immunosuppressive drug used in kidney transplantation. Whether the mTOR inhibitor is associated with reduced risk of cancer development and mortality after kidney transplantation is controversial. METHODS: We conducted a nationwide population-based study. Patients who did not have malignancy history and received kidney transplantation between 2010 and 2013 were enrolled. Recipients who had mTOR inhibitors (n = 430) for more than 30 days comprised the study group; 1720 recipients who did not have mTOR inhibitors comprised the control group. The primary outcome is the development of cancer after kidney transplantation. These patients were followed until the first-time admission with diagnosis of cancer, death, or the end of 2014. A Cox proportional-hazard model was used to determine the risk of cancer development and all-cause mortality. RESULTS: During the 35-month median duration of observation, there were 16 and 61 patients with cancer development in the study group and the control group, respectively. The cancer incidence was 12.8 and 12.4 per 1000 person-years. There were 10 and 135 mortality cases, with the incidence rate of 7.8 and 26.9 per 1000 person-years. After multivariable adjustment, the mTOR inhibitors users were not associated with reduced risk of new cancer development as compared with control (hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.46-1.60; P = .63), nor risk of all-cause mortality (HR, 0.70; 95% CI, 0.33-1.46; P = .34). CONCLUSIONS: The use of mTOR inhibitors was not associated with a reduction in the risk of cancer development and all-cause mortality in kidney transplantation recipients.

Three-dimensional charge density wave order in YBa2Cu3O6.67 at high magnetic fields.

Charge density wave (CDW) correlations have been shown to universally exist in cuprate superconductors. However, their nature at high fields inferred from nuclear magnetic resonance is distinct from that measured with x-ray scattering at zero and low fields. We combined a pulsed magnet with an x-ray free-electron laser to characterize the CDW in YBa2Cu3O6.67 via x-ray scattering in fields of up to 28 tesla. While the zero-field CDW order, which develops at temperatures below ~150 kelvin, is essentially two dimensional, at lower temperature and beyond 15 tesla, another three-dimensionally ordered CDW emerges. The field-induced CDW appears around the zero-field superconducting transition temperature; in contrast, the incommensurate in-plane ordering vector is field-independent. This implies that the two forms of CDW and high-temperature superconductivity are intimately linked.

Orbital Reconstruction in a Self-assembled Oxygen Vacancy Nanostructure.

We demonstrate the microscopic role of oxygen vacancies spatially confined within nanometer inter-spacing (about 1 nm) in BiFeO3, using resonant soft X-ray scattering techniques and soft X-ray spectroscopy measurements. Such vacancy confinements and total number of vacancy are controlled by substitution of Ca(2+) for Bi(3+) cation. We found that by increasing the substitution, the in-plane orbital bands of Fe(3+) cations are reconstructed without any redox reaction. It leads to a reduction of the hopping between Fe atoms, forming a localized valence band, in particular Fe 3d-electronic structure, around the Fermi level. This band localization causes to decrease the conductivity of the doped BiFeO3 system.

Direct characterization of photoinduced lattice dynamics in BaFe2As2.

Ultrafast light pulses can modify electronic properties of quantum materials by perturbing the underlying, intertwined degrees of freedom. In particular, iron-based superconductors exhibit a strong coupling among electronic nematic fluctuations, spins and the lattice, serving as a playground for ultrafast manipulation. Here we use time-resolved X-ray scattering to measure the lattice dynamics of photoexcited BaFe2As2. On optical excitation, no signature of an ultrafast change of the crystal symmetry is observed, but the lattice oscillates rapidly in time due to the coherent excitation of an A1g mode that modulates the Fe-As-Fe bond angle. We directly quantify the coherent lattice dynamics and show that even a small photoinduced lattice distortion can induce notable changes in the electronic and magnetic properties. Our analysis implies that transient structural modification can be an effective tool for manipulating the electronic properties of multi-orbital systems, where electronic instabilities are sensitive to the orbital character of bands.

The juxtamembrane sequence of the Hepatitis C virus polymerase can affect RNA synthesis and inhibition by allosteric polymerase inhibitors.

The Hepatitis C virus (HCV) RNA-dependent RNA polymerase (RdRp), nonstructural protein 5B (NS5B), is anchored in the membrane through a C-terminal helix. A sequence of ca. 12 residues that connects the catalytically competent portion of the RdRp and the C-terminal helix, the juxtamembrane sequence (JMS), has a poorly defined role in RdRp function in a large part since it is translated from a cis-acting RNA element (CRE) that is essential for HCV replication. Using a HCV replicon that transposed a second copy of CRE to the 3' UTR of the HCV replicon, we demonstrate that amino acid substitutions in the JMS were detrimental for HCV replicon replication. Substitutions in the JMS also resulted in a defect in de novo-initiated RNAs synthesis in vitro and in a cell-based reporter assay. A nonnucleoside inhibitor of the NS5B that binds to the catalytic pocket was less potent in inhibiting NS5B in the presence of JMS mutations. The JMS mutants exhibit reduced stability in thermodenaturation assays, suggesting that the JMS helps confer a more stable conformation to NS5B that could impact RNA synthesis.

Short-term result of renal transplantation using extracorporeal membrane oxygenation-supported brain-dead donors.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is now widely used to maintain hemodynamic stability after traumatic events among medical centers. It remains unclear whether renal transplantation using ECMO-supported donors carries poorer outcomes. METHODS: From February 2010 to March 2013, we performed 9 renal transplantations (6 females and 3 males) from 5 ECMO-supported donors. Demographic data and clinical outcomes were retrospectively analyzed through medical chart review. RESULTS: The mean follow-up period was 15 ± 9 months (range: 8-37). Eight of the 9 grafts remained functioning within the follow-up period. One (11.1%) graft loss was noted after repeated acute rejection. Acute rejection occurred in 3/9 (33%) of cases. Delayed graft function was also observed in 3/9 (33%) of cases. CONCLUSION: Renal transplantation using ECMO-supported brain-dead donors was not associated with an unacceptably high rate of graft loss in this short-term follow-up. It might be an alternative way to expand donor pools.

Titanium dxy ferromagnetism at the LaAlO3/SrTiO3 interface.

A number of recent transport and magnetization studies have shown signs of ferromagnetism in the LaAlO3/SrTiO3 heterostructure, an unexpected property with no bulk analogue in the constituent materials. However, no experiment thus far has provided direct information on the host of the magnetism. Here we report spectroscopic investigations of the magnetism using element-specific techniques, including X-ray magnetic circular dichroism and X-ray absorption spectroscopy, along with corresponding model calculations. We find direct evidence for in-plane ferromagnetic order at the interface, with Ti(3+) character in the dxy orbital of the anisotropic t2g band. These findings establish a striking example of emergent phenomena at oxide interfaces.

Chemical reactivity of brome mosaic virus capsid protein.

Viral particles are biological machines that have evolved to package, protect, and deliver the viral genome into the host via regulated conformational changes of virions. We have developed a procedure to modify lysine residues with S-methylthioacetimidate across the pH range from 5.5 to 8.5. Lysine residues that are not completely modified are involved in tertiary or quaternary structural interactions, and their extent of modification can be quantified as a function of pH. This procedure was applied to the pH-dependent structural transitions of brome mosaic virus (BMV). As the reaction pH increases from 5.5 to 8.5, the average number of modified lysine residues in the BMV capsid protein increases from 6 to 12, correlating well with the known pH-dependent swelling behavior of BMV virions. The extent of reaction of each of the capsid protein's lysine residues has been quantified at eight pH values using coupled liquid chromatography-tandem mass spectrometry. Each lysine can be assigned to one of three structural classes identified by inspection of the BMV virion crystal structure. Several lysine residues display reactivity that indicates their involvement in dynamic interactions that are not obvious in the crystal structure. The influence of several capsid protein mutants on the pH-dependent structural transition of BMV has also been investigated. Mutant H75Q exhibits an altered swelling transition accompanying solution pH increases. The H75Q capsids show increased reactivity at lysine residues 64 and 130, residues distal from the dimer interface occupied by H75, across the entire pH range.

Fragile magnetic ground state in half-doped LaSr2Mn2O7.

We investigated the orbital and antiferromagnetic ordering behaviors of the half-doped bilayer manganite La(2-2x)Sr(1+2x)Mn2O7 (x ≃ 0.5) by using Mn L(2,3)-edge resonant soft x-ray scattering. Resonant soft x-ray scattering reveals the CE-type orbital order below T(oo) ≃ 220 K, which shows partial melting behavior below T(m) ≃ 165 K. We also found coexistence CE- and A-type antiferromagnetic orders. Both orders involve the CE-type orbital order with nearly the same orbital character and are coupled with each other. These results manifest that the ground state with the CE-type antiferromagnetic order is easily susceptible to destabilization into the A-type one even with a small fluctuation of the doping level, as suggested by the extremely narrow magnetic phase boundaries at x ≃ 0.5±0.005.

Tumor necrosis factor alpha promoter polymorphism in posttransplantation diabetes mellitus of renal transplant recipients.

Posttransplantation diabetes mellitus (PTDM) is a major complication in renal transplant recipients. Some studies have demonstrated that tumor necrosis factor alpha (TNF-α) expression and its genetic polymorphism are associated with diabetes mellitus. We investigated this association in Asian renal transplant recipients. Polymerase chain reaction-restriction-fragment length polymorphism was used to measure TNF-α G-238A and G-308A gene polymorphisms among 241 nonposttransplantation diabetic subjects and 73 PTDM patients. PTDM patients showed higher values of body weight and body mass index (BMI) than the non-PTDM group. However, no significant association was observed between TNF-α G-238A and TNF-α G-308A polymorphisms with PTDM incidence, gender, age at transplantation, follow-up duration, BMI, or type of immunosuppression.

Interface ferromagnetism and orbital reconstruction in BiFeO3-La(0.7)Sr(0.3)MnO3 heterostructures.

We report the formation of a novel ferromagnetic state in the antiferromagnet BiFeO3 at the interface with ferromagnet La(0.7)Sr(0.3)MnO3. Using x-ray magnetic circular dichroism at Mn and Fe L(2,3) edges, we discovered that the development of this ferromagnetic spin structure is strongly associated with the onset of a significant exchange bias. Our results demonstrate that the magnetic state is directly related to an electronic orbital reconstruction at the interface, which is supported by the linearly polarized x-ray absorption measurement at the oxygen K edge.