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Halide perovskites have shown promising potential for direct X-ray detection due to their high X-ray absorption coefficient, low trap states and convenient fabrication process. However, it is still a challenge to achieve high sensitivity, low dark current and low detection limit in a single material. The deep reason for this is the trade-off between the material’s μτproduct and resistivity. Here we report the construction of an organic–inorganic hybrid anti-perovskite ((2-Habch)3Cl(PtI6)) with indirect transition and low orbital symmetry at the band edge to achieve an ultralong intrinsic lifetime and thus break the trade-off. (2-Habch)3Cl(PtI6) achieves an unprecedented long carrier lifetime of >3 ms, leading to a large μτproduct of 6.25 × 10−3cm2V−1and high resistivity of 1012Ω cm, outperforming most X-ray detection materials. These properties enabled the development of X-ray detectors that simultaneously achieve an ultralow dark current of 0.21 nA cm−2, high sensitivity of 1.0 × 104µC Gyair−1cm−2, ultralow detection limit of 2.4 nGyairs−1and excellent operational stability with no observable baseline drift, outperforming state-of-the-art perovskite single-crystal detectors. The rare combination of high performance in almost every figure of merit in the anti-perovskite-based X-ray detector could enable new-generation X-ray detection systems.

Auxin (indole-3-acetic acid, IAA) has a considerable impact on the regulation of plant carbohydrate levels and growth, but the mechanism by which it regulates sugar levels in plants has received little attention. In this study, we found that exogenous IAA altered fructose (Fru), glucose (Glc), and sucrose (Suc) concentrations in shoot tips mainly by regulating MdSUSY1, MdFRK2, MdHxK1and MdSDH2transcript levels. Additionally, we used 5-year-old ‘Royal Gala’ apple trees to further verify that these genes play primary roles in regulating sink strength. The results showed that MdSUSY1, MdFRK2, MdHxK1/3and MdSDH2might be major contributors to sink strength regulation. Taken together, these results provide new insight into the regulation of the carbohydrate metabolism mechanism, which will be helpful for regulating sink strength and yield.

Background. Because of the relative rarity of breast cancer in males, data have not been sufficient to support a definitive analysis of pertinent prognostic factors. Remarkably, no studies of male patients with breast cancer have presented survival information based on the number of histologically positive axillary nodes, the most sensitive single indicator of prognosis in women with breast cancer. Methods. In this study, the clinical course of breast cancer was documented for 335 male patients registered from 1965 through 1986. For patients to be eligible, diagnoses had to be made within 3 months of registration and the patients had to have histologic confirmation and receive part or all of their initial treatment at 1 of 11 cancer centers participating in the International Patient Data Exchange System. Results. The survival rate at 10 years was 84% for patients with histologically negative nodes, 44% for those with one to three positive nodes, and 14% for the group with four or more histologically positive nodes. The survival rates at 5 years were 90%, 73%, and 55%, respectively. In a multivariable analysis, the risk of death due to breast cancer for a patient with four or more histologically positive nodes was 6.75 times that of a patient with negative nodes. Conclusions. The findings of the authors indicate the following: (1) The number of histologically positive axillary nodes and, to a lesser degree, tumor diameter are significant prognostic factors for breast cancer in male patients. (2) The prognosis of breast cancer is the same in male and female patients when compared on the basis of the number of histologically positive nodes. Cancer 1993; 71:154-61.

The thermal contact conductance is an important problem in the field of heat transfer. In this research, a three-dimensional fractal theory based on the thermal contact conductance model is presented. The topography of the contact surfaces was fractal featured and determined by fractal parameters. The asperities in the microscale were considered as elastic, elastic-plastic, or plastic deformations. The real contact area of the asperities could be obtained based on the Hertz contact theory. It was assumed that the rough contact surface was composed of numerous discrete and parallel microcontact cylinders. Consequently, the thermal contact conductance of the surface roughness was composed of the thermal constriction conductance of microcontacts and the air medium thermal conductance of microgaps. The thermal contact conductance of rough surfaces could be calculated by the microasperities integration. An experimental set-up with annular interface was designed to verify the presented thermal contact conductance model. Three materials were used for the thermal contact conductance analysis with different fractal dimensions Dand fractal roughness parameters G. The numerical results demonstrated that the thermal contact conductance could be affected by the elastic-plastic deformation of the asperities and the gap thermal conductance should not be ignored under the lower contact load. The presented model would provide a theoretical basis for thermal transfer engineering application.

Within the framework of Dyson-Schwinger equations, we discuss the chiral phase transition of QCD with a chiral chemical potential p5 as an additional scale. We focus especially on the issues related to the widely accepted as well as interesting critical end point (CEP). With the help of a scalar susceptibility, we find that there might be no CEP5 in the T - μ5 plane, and the phase transition in the T - μ5 plane might be totally crossover when μ < 50 MeV, which has apparent consistency with the lattice QCD calculation. Our study may also provide some useful hints to some other studies related to μ5. [ABSTRACT FROM AUTHOR]

Since the baryon-number susceptibilities are correlated with the cumulant of baryon-number fluctuations in experiments, we do calculations of the susceptibilities and compare them with the experimental fluctuation data under the framework of the Dyson-Schwinger equations (DSEs) approach. We compare our results with lattice QCD and experimental data at RHIC. The fitness of the results indicates that under the framework of DSEs, we can deal with the problems of heavy ion collisions properly. [ABSTRACT FROM AUTHOR]

In this paper, chiral symmetry breaking and its restoration are investigated in the mean field approximation of Nambu-Jona-Lasinio model. A first-order phase transition exists at low temperature, but is smeared out at high temperature. We discuss the rationality of using susceptibilities as the criteria to determine the crossover region as well as the critical point. Based on our results, it is found that to define a critical band instead of an exclusive line in this region might be a more suitable choice. [ABSTRACT FROM AUTHOR]

The production’s SPL distribution of the U.S. coal supply enterprises from 1983 to 2011 was obtained from the empirical analysis. And the nameplate capacity’s SPL distribution of the U.S. existing electric generating units in 2009 was obtained. Based on a universal bipartite model of the energy supply-demand network, the numerical results of the U.S. coal supply-demand network are obtained, which are in good agreement with the empirical results.

Parameterizations that use mesh simplification to build the base domain always adopt the vertex removal scheme. This paper applies edge collapse to constructing the base domain instead. After inducing the parameterization of the original mesh over the base domain, new algorithms map the new vertices in the simplified mesh back to the original one according to the edge transition sequence to integrate the parameterization. We present a direct way, namely edge classification, to deduce the sequence. Experimental results show that the new parameterization features considerable saving in computing complexity and maintains smoothness.

A Poincaré-covariant quark + diquark Faddeev equation, augmented by a statistical implementation of the Schlessinger point method for the interpolation and extrapolation of smooth functions, is used to compute nucleon elastic form factors on 0 ≤ Q² ≤ 18 mN²(mN is the nucleon mass) and elucidate their role as probes of emergent hadronic mass in the Standard Model. The calculations expose features of the form factors that can be tested in new generation experiments at existing facilities, e.g., a zero in GEp/GMp, a maximum in GEn/GMn, and a zero in the proton's d-quark Dirac form factor, F1d. Additionally, examination of the associated light-front-transverse number and anomalous magnetization densities reveals inter alia: a marked excess of valence u quarks in the neighborhood of the proton's center of transverse momentum, and that the valence d quark is markedly more active magnetically than either of the valence u quarks. The calculations and analysis also reveal other aspects of nucleon structure that could be tested with a high-luminosity accelerator capable of delivering higher beam energies than are currently available. [ABSTRACT FROM AUTHOR]

The structures of strange quark stars are studied within a quasiparticle model obtained by the two-loop approximation. A softer equation of state yields a smaller maximum mass, a smaller radius, and makes the surface energy density and the surface quark chemical potential larger. The parameter space is obtained under the following constraints: the maximum mass of the strange quark star should be larger than 2.0 solar masses, which matches the masses of PSR J0348+0432 and PSR J1614-2230, and the surface energy density should be larger than 2.80×1014 g/cm³. In our parameter space, the surface quark chemical potential is smaller than 308 MeV which is the critical quark chemical potential in QCD without electromagnetism. Also, the tidal Love number k2 and deformability Λ are calculated for a 1.4-solar-mass strange quark star. A softer equation of state yields a smaller Λ(1.4) and leads to a strange quark star that is more compact and less likely to be tidally deformed. The data of GW170817 indicate that the upper bound of Λ(1.4) is 800 for the low-spin prior, which gives an upper bound of the parameter ζ of the running coupling constant αs and gives a lower bound of the vacuum pressure density B, i.e., ζ<0.098 GeV, B>(0.111 GeV)4. Moreover, the constraint on ζ also plays an important role in phenomenological studies of the quark-gluon plasma. [ABSTRACT FROM AUTHOR]

In this paper, we explore the dynamical chiral symmetry breaking by employing a two-flavor Nambu-Jona-Lasinio (NJL) model with constant external magnetic field. After changing the coupling strength of the NJL model, we found that the Wigner-Weyl solution and Nambu-Goldstone solution of the gap equation could coexist. Even though the gap equation only has Nambu-Goldstone solution at zero temperature, the Wigner-Weyl solution may appear when magnetic field strength and temperature are nonzero. For the Nambu-Goldstone solution, magnetic field and temperature have opposite impact on the chiral dynamical mass. In the chiral limit, the magnetic field dependence of chiral dynamical mass reveals the existence of inverse magnetic catalysis for the Wigner-Weyl solution. However, the two phases have different responses to the magnetic field and temperature in the chiral limit but the same beyond chiral limit. Furthermore, the order of the transition from the Nambu-Goldstone phase to Wigner-Weyl phase depends on the choice of model parameters. We have also calculated the susceptibilities of dynamical mass with respect to the temperature. [ABSTRACT FROM AUTHOR]

Introducing constant background fields into the noncommutative gauge theory, we first obtain a Hermitian fermion Lagrangian which involves a Lorentz violation term, then we generalize it to a new deformed canonical noncommutation relations for fermion field. Massless neutrino oscillation in the deformed canonical noncommutation relations is analyzed. The restriction of the noncommutative coefficients is also discussed. By comparing with the existing experimental data of conventional neutrino oscillations, the order of noncommutative deformed coefficients is given from different ways. [ABSTRACT FROM AUTHOR]

The effect of chiral imbalance on the QCD phase structure is studied in a framework of Dyson-Schwinger equations. It is found that the chiral phase transition is always a crossover in the T - μ5 plane when μ is 0 MeV or small values. The trail of the critical endpoints (CEPs) along with the variation of the chiral chemical potential is given. We find that the effect of μ5 is somewhat different from the existing chiral model calculations; namely, the CEP first moves roughly along the phase boundary of T - μ plane in a smaller μ direction, as in the chiral model calculations, but turns in the opposite direction to move away from the small chemical potential region, which has never been observed before. In addition, we also discuss the possibility of whether the study at finite temperature and chiral chemical potential can provide some useful information for the detection of the CEP at finite temperature and baryon chemical potential, since the former can be calculated in lattice QCD without the sign problem. [ABSTRACT FROM AUTHOR]

Based on the study of the linear response of the fermion propagator in the presence of an external scalar field, we calculate the staggered spin susceptibility in the low-energy limit in the framework of the Dyson-Schwinger approach. We analyze the effect of a finite gauge boson mass on the staggered spin susceptibility in both the Nambu phase and the Wigner phase. It is found that the gauge boson mass suppresses the staggered spin susceptibility in the Wigner phase. In addition, we try to give an explanation for why the antiferromagnetic spin correlation increases when the doping is lowered. [ABSTRACT FROM AUTHOR]

In this paper, the relations of four different susceptibilities (i.e., the chiral susceptibility, the fermion number susceptibility, the thermal susceptibility, and the staggered spin susceptibility) are investigated both in and beyond the chiral limit. To this end, we numerically solve the finite-temperature version of the truncated Dyson-Schwinger equations for the fermion and boson propagator. It is found that, in the chiral limit, the four susceptibilities give the same critical temperature and signal a typical second order phase transition. But the situation changes beyond the chiral limit: the critical temperatures from the chiral and the thermal susceptibilities are different, which shows that to define a critical region instead of an exclusive point for crossover might be a more suitable choice. Meanwhile, both the fermion number and the staggered spin susceptibilities have no singular behaviors any more; this may mean that they are no longer available to describe the crossover properties of the system. [ABSTRACT FROM AUTHOR]

In this paper, we develop a new method that is different from the Schwinger proper time method to deduce the fermion propagator with a constant external magnetic field. In the NJL model, we use this method to find the gap equation at zero and nonzero temperature and give the numerical results and phase diagram between the magnetic field and temperature. Additionally, we introduce the current mass to study the susceptibilities because there is a new parameter (the strength of the external magnetic field) in this problem. Corresponding to this new parameter, we define a new susceptibility XB to compare with the other two susceptibilities xc (chiral susceptibility) andXt (thermal susceptibility). All three susceptibilities show that when the current mass is not zero, the phase transition is a crossover, while for comparison, in the chiral limit, the susceptibilities show a second order phase transition. Last, we give the critical coefficients of different susceptibilities in the chiral limit. [ABSTRACT FROM AUTHOR]