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The anomalous strange metal phase found in high-Tc cuprates does not follow the conventional condensed-matter principles enshrined in the Fermi liquid and presents a great challenge for theory. Highly precise experimental determination of the electronic self-energy can provide a test bed for theoretical models of strange metals, and angle-resolved photoemission can provide this as a function of frequency, momentum, temperature and doping. Here we show that constant energy cuts through the nodal spectral function in (Pb,Bi)2Sr2−xLaxCuO6+δ have a non-Lorentzian lineshape, consistent with a self-energy that is k dependent. This provides a new test for aspiring theories. Here we show that the experimental data are captured remarkably well by a power law with a k-dependent scaling exponent smoothly evolving with doping, a description that emerges naturally from anti-de Sitter/conformal-field-theory based semi-holography. This puts a spotlight on holographic methods for the quantitative modelling of strongly interacting quantum materials like the cuprate strange metals. Strange metal behaviour of high-Tc superconductors, characterised by unconventional electrical and thermodynamic properties, still poses challenges for theory. Smit et al. report experimental features in the self-energy of a strange metal that are consistent with predictions by holographic theoretical methods. [ABSTRACT FROM AUTHOR]

The triangular spin lattice of NiBr 2 is a canonical example of the frustrated helimagnet that shows a collinear commensurate antiferromagnetic to an incommensurate spin helix phase transition on cooling. Herein, we have studied a self-flux grown NiBr 2 single crystal by neutron diffraction and low temperature magnetization measurements at fields up to 14 T. Experimental findings enable the deduction of the driving force responsible for the spin spiral ordering. The neutron diffraction data reveal satellite peaks representing characteristic features of an incommensurate magnetic state. The satellites develop symmetrically below T N = 44.0 (1) K , replacing the main magnetic reflections. Interestingly, a field-induced incommensurate to commensurate spin phase transition has been successfully demonstrated, which enforces the spin helix to restore the high temperature compensated antiferromagnetic structure. This reorientation can be described by a spin-flop in the (a–b) basal plane of a triangular spin lattice system. The findings offer a novel way for spin helix control of incommensurate phases, having immense scientific and technological implications in the next-generation data storage devices. [ABSTRACT FROM AUTHOR]

Ceratovacuna lanigera Zehntner is a major leaf pest of sugarcane. Widely distributed, it affects both the yield and quality of sugarcane in China. This study aimed to assess real yield and sugar yield losses, and the effect of C. lanigera damage on emergence of newly planted and ratoon cane under current production levels. Field experiments were carried out from 2014 to 2016 in Yunnan Province China. At maturity, plants were harvested and weighed to determine yield, and the effect on sugarcane quality and sucrose content analyzed. Real yield decreased by average of 46,185 kg hm--2 (range: 37,545-61,845 kg hm--2) in damaged versus undamaged areas, with an average yield loss rate of 35.9% (28.5-45.7%). Juice yield decreased by an average of 3.01% (2.4-4.13%) and sucrose content by 6.38% (5.48-8.16%). Juice brix decreased by an average of 7.66°BX (6.95-9.05°BX) and juice gravity purity by 12.35% (8.43-19.97%). In contrast, the reducing sugar content increased by an average of 1.21% (1.01-1.3%). Emergence rates of newly planted cane decreased by an average of 26.0% (24.7-27.3%). The emergence number of ratoon cane decreased by 66,834 hm22 (57,429-76,238 hm--2) and relative emergence loss rates of ratoon cane decreased by an average of 57.8% (57.6-58.0%). These findings confirm that C. lanigera damage severely affects sugarcane yield and quality in Yunnan Province. The results will help the implementation of effective control measures, thereby supporting sustainable development of the Chinese sugar industry. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effects of maternal gestational diabetes mellitus (GDM) and breast feeding on childhood overweight and obesity in a mainland Chinese population. The incidence of and factors associated with overweight and obesity were compared between children of mothers with (n=1068) and without (n=1756) GDM. The independent roles of the associated factors were examined by multiple logistic regression analysis. The incidence of overweight was higher (16.6 v. 12.6%, P=0.002) in the GDM group, but that of obesity was not different (10.7 v. 12.0%, P=0.315). At age 1–2 and 2–5 years, no difference in overweight (11.0 v. 12.0%, P=0.917, and 15.7 v. 14.6%, P=0.693, respectively) was found, while obesity (8.0 v. 13.6%, P=0.019, and 8.4 v. 13.4%, P=0.014, respectively) was less frequent in the GDM offspring. At age 5–10 years, increased overweight (22.2 v. 12.1%, P<0.001) and obesity (15.9 v. 9.0%, P=0.001) were found in the GDM group, which was associated with maternal obesity, being born large-for-gestational age, male gender and formula feeding. After adjusting for confounding factors, GDM remained an independent determinant of offspring overweight and obesity (aOR 2.28, 95% CI 1.61–3.22), suggesting that the effects of GDM were independent of breast feeding, as well as of maternal obesity and birth size. [ABSTRACT FROM PUBLISHER]

(Mn,Fe)2(P,Si) single crystals have been grown by flux method. Single crystal X-ray diffraction demonstrates that Mn0.83Fe1.17P0.72Si0.28 crystallizes in a hexagonal Fe2P crystal structure (space group P62m) at both 100 and 280 K, in the ferromagnetic and paramagnetic states, respectively. Magnetization measurements show that the crystals display a first-order ferromagnetic phase transition at their Curie temperature (TC). The preferred magnetization direction is along the c axis. A weak magnetic anisotropy of K 1 = 0.28 × 106 J/m³ and K 2 = 0.22 × 106 J/m³ is found at 5 K. A series of discontinuous magnetization jumps is observed far below TC by increasing the field at constant temperature. These magnetization jumps are irreversible, occur spontaneously at a constant temperature and magnetic field, but can be restored by cycling across the first-order phase transition. [ABSTRACT FROM AUTHOR]

We report superconductivity at and magnetic order at in the semimetallic noncentrosymmetric half-Heusler compound ErPdBi. The upper critical field, Bc2, has an unusual quasi-linear temperature variation and reaches a value of 1.6 T for . Magnetic order is found below Tc and is suppressed at for . Since , the interaction of superconductivity and magnetism is expected to give rise to a complex ground state. Moreover, electronic-structure calculations show that ErPdBi has a topologically nontrivial band inversion and thus may serve as a new platform to study the interplay of topological states, superconductivity and magnetic order. [ABSTRACT FROM AUTHOR]

We present a simple but versatile piezoelectric coefficient measurement system, which can measure the longitudinal and transverse piezoelectric coefficients in the pressing and bending modes, respectively, at different applied forces and a wide range of frequencies. The functionality of this measurement system has been demonstrated on three samples, including a PbZr0.52Ti0.48O3 (PZT) piezoelectric ceramic bulk, a ZnO thin film, and a laminated piezoelectric film sensor. The static longitudinal piezoelectric coefficients of the PZT bulk and the ZnO film are estimated to be around 210 and 8.1 pC/N, respectively. The static transverse piezoelectric coefficients of the ZnO film and the piezoelectric film sensor are determined to be, respectively, -0.284 and -0.031 C/m2. [ABSTRACT FROM AUTHOR]

The correlated metal UCoGe is a weak itinerant ferromagnet with a Curie temperature T=3 K and a superconductor with a transition temperature T=0.6 K. We review its basic thermal, magnetic-on the macro and microscopic scale-and transport properties, as well as the response to high pressure. The data unambiguously show that superconductivity and ferromagnetism coexist below T=0.6 K and are carried by the same 5 f electrons. We present evidence that UCoGe is a p-wave superconductor and argue that superconductivity is mediated by critical ferromagnetic spin fluctuations. [ABSTRACT FROM AUTHOR]

Phase separation and extreme sensitivity to disorder and defects are key features of electronic order near quantum phase transitions. Neutron depolarization imaging and neutron Larmor diffraction are new experimental techniques capable of providing detailed real-space and reciprocal-space information, respectively, on the existence and nature of phase separations. Proof-of-principle depolarization imaging in PdNi, CePdRh and NbFe suggests distinct differences of the real-space distribution of ferromagnetic moments and Curie temperatures in materials at ferromagnetic quantum phase transitions. This compares with neutron Larmor diffraction which provides high-resolution reciprocal-space information of phase separation and the absence of quantum criticality in the itinerant helimagnet MnSi or the parasitic nature of small moment antiferromagnetism in URuSi. [ABSTRACT FROM AUTHOR]

Knowing that infection of high-risk human papillomavirus (HPV) causes virtually all cervical cancer (CC), the long-term outcomes of HPV infection, especially the absolute risk and time lapse of developing CC, are beyond the scope of ordinary follow-up study owing to ethical concerns. The present study followed the natural history and long-term outcomes of HPV infection in a cohort of women by national health insurance care and data linkage without additional disturbance. The status of cervical HPV infection was determined in 1708 healthy women, aged 20-90 (median 43), enrolled from 10 hospitals in seven cities around the island country of Taiwan. Records of consecutive Pap smear results and cancer reports of 108 cytology-negative, HPV-positive and 1202 cytology- and HPV-negative women with no prior record of CC or abnormal cervical cytology were retrospectively analysed for a duration of up to 75 months (median 61 months). The cumulative incidences of high-grade squamous intraepithelial lesion (HSIL) and in situ/invasive cancer in HPV-positive women were 5.6 and 3.7%, respectively, and those in HPV-negative women were 0.3 and 0%. After adjusting for other risk factors, HPV-positive subjects had 24.9 (95% CI: 7.0-108.3; P<0.0001) folds of risk of developing HSIL or above cervical neoplasia as compared to HPV-negative subjects, whereas risk for low-grade intraepithelial lesion and atypical squamous cytology was not increased. The study showed that women with a prevalent infection of high-risk HPV had a 4% cumulative risk for CC in 6 years, whereas those tested negative had little risk. The result supports an HPV test-orientated CC screening programme with intervals of at least 5 years. [ABSTRACT FROM AUTHOR]

Extra-corporeal life support (ECLS) has been applied successfully to congenital respiratory defects but less optimally to acquired pulmonary failure. We extended this support to certain extreme complexities of patients with acute respiratory distress. From January 2003 to June 2005, 16 (nine men and seven women) patients refractory to ventilator support were treated with ECLS. Their median age was 32.4 years (1.5–70). The triggering events were pulmonary haemorrhage ( n = 4), pneumonia ( n = 7), aspiration ( n = 2) and pancreatitis ( n = 3). The indications for support were hypoxaemia in 13 and hypercapnia in three patients. Ten (63%) met the criteria of fast entry. Thirteen (81%) received veno-venous (V-V) mode support and the other three received veno-arterial mode support initially, but then converted to V-V mode after sufficient oxygenation stabilised haemodynamics. Initial pump flow was maximised to improve (mean 3250 ± 1615 ml/min) to improve the oxygenation. Four patients with active pulmonary haemorrhage were heparin free in the first 12–24 h of support without complications. Excluding one prematurely terminated patient because of brain permanent damage, the duration of support was 162 ± 95 h (67–363). Eleven (69%) weaned successfully from ECLS and 10 (63%) discharged and regained normal pulmonary performance in a median of 26.8 months follow-up. Pulmonary support using ECLS was feasible in selected patients with acute respiratory distress. Modification of guidelines for liberal use, early deployment before secondary organ damage and prevention of complications during support were the key to final success. [ABSTRACT FROM AUTHOR]

The compliance effect of a high-speed ball-screw feed-drive system is modelled in this work. A mechanical model of a ball-screw feed drive system including the motor, ball-screw, coupling, supporting bearing, linear guide and machine structure was developed. It was found that at high acceleration, the mechanical compliance caused a significant contouring error. Smoothing the acceleration and deceleration control input command did improve the transient deviation in the contouring error. However, the steady state error caused by the elastic elongation in the mechanical elements was not improved. It was also shown that the inertia force of the slide and saddle comprised the dominant loading on a high speed machine tool drive mechanism. A topology structure optimisation method is proposed to reduce the moving weight. This method can help the designer efficiently reduce the moving weight of a machine tool axis in a systematic way. More than a 30% weight reduction was demonstrated in a spindle carrier structural design. [ABSTRACT FROM AUTHOR]

Experimental results for a novel transmission system using self-wrapped optical code division multiplexed signals to achieve enhanced data security at the physical layer of the optical network are presented. Key distribution is performed by encoding and time-spreading, thus allowing for both cryptographic and steganographic security in the public network. [ABSTRACT FROM AUTHOR]

A scalable OCDMA platform for testing different avionics applications at Lockheed Martin has been designed and built. The platform enables communication at OC-24 per user with raw BER<10-12 using fast wavelength-hopping, time-spreading prime codes with picosecond optical pulses. A novel optical encoder/decoder pair enables a connectivity approaching a so-called ‘one-time pad’ security and eavesdropping studies. [ABSTRACT FROM AUTHOR]

The original version of this Article contained an error in the right-hand y-axis of Fig. 2c, which incorrectly read 'S/2e (pA)'. The correct version states 'nA' in place of 'pA'. This has been corrected in both the PDF and HTML versions of the Article. [ABSTRACT FROM AUTHOR]

Dopants and impurities are crucial in shaping the ground state of host materials: semiconducting technology is based on their ability to donate or trap electrons, and they can even be used to transform insulators into high temperature superconductors. Due to limited time resolution, most atomic-scale studies of the latter materials focussed on the effect of dopants on the electronic properties averaged over time. Here, by using atomic-scale current-noise measurements in optimally doped Bi2Sr2CaCu2O8+x, we visualize sub-nanometre sized objects where the tunnelling current-noise is enhanced by at least an order of magnitude. We show that these objects are previously undetected oxygen dopants whose ionization and local environment leads to unconventional charge dynamics resulting in correlated tunnelling events. The ionization of these dopants opens up new routes to dynamically control doping at the atomic scale, enabling the direct visualization of local charging on e.g. high-Tc superconductivity. The effects of dopants in high-temperature superconductors on the surrounding electronic structure give insights into their unconventional microscopic behaviour. Here the authors find a new class of defects that they identify as oxygen dopants whose ionization and local environment induce unusual atomic-scale charge dynamics. [ABSTRACT FROM AUTHOR]

In an ideal 3D topological insulator (TI), the bulk is insulating and the surface conducting due to the existence of metallic states that are localized on the surface; these are the topological surface states. Quaternary Bi-based compounds of Bi2−xSbxTe3−ySey with finely-tuned bulk stoichiometries are good candidates for realizing ideal 3D TI behavior due to their bulk insulating character. However, despite its insulating bulk in transport experiments, the surface region of Bi2−xSbxTe3−ySey crystals cleaved in ultrahigh vacuum also exhibits occupied states originating from the bulk conduction band. This is due to adsorbate-induced downward band-bending, a phenomenon known from other Bi-based 3D TIs. Here we show, using angle-resolved photoemission, how an EUV light beam of moderate flux can be used to exclude these topologically trivial states from the Fermi level of Bi1.46Sb0.54Te1.7Se1.3 single crystals, thereby re-establishing the purely topological character of the low lying electronic states of the system. We furthermore prove that this process is highly local in nature in this bulk-insulating TI, and are thus able to imprint structures in the spatial energy landscape at the surface. We illustrate this by 'writing' micron-sized letters in the Dirac point energy of the system. [ABSTRACT FROM AUTHOR]