On defining partition entropy by inequalities

Partition entropy is the numerical metric of uncertainty within a partition of a finite set, while conditional entropy measures the degree of difficulty in predicting a decision partition when a condition partition is provided. Since two direct methods exist for defining conditional entropy based on its partition entropy, the inequality postulates of monotonicity, which conditional entropy satisfies, are actually additional constraints on its entropy. Thus, in this paper partition entropy is defined as a function of probability distribution, satisfying all the inequalities of not only partition entropy itself but also its conditional counterpart. These inequality postulates formalize the intuitive understandings of uncertainty contained in partitions of finite sets.We study the relationships between these inequalities, and reduce the redundancies among them. According to two different definitions of conditional entropy from its partition entropy, the convenient and unified checking conditions for any partition entropy are presented, respectively. These properties generalize and illuminate the common nature of all partition entropies

The Role of Active Oxide Species for Electrochemical Water Oxidation on the Surface of 3d-Metal Phosphides

Transition metal phosphides (TMPs) have recently been utilized as promising electrocatalysts for oxygen evolution reaction (OER) in alkaline media. The metal oxides or hydroxides formed on their surface during the OER process are hypothesized to play an important role. However, their exact role is yet to be elucidated. Here unambiguous justification regarding the active role of oxo(hydroxo) species on O-Ni(1−x)FexP2 nanosheet with pyrite structure is shown. These O-Ni(1−x)FexP2 (x = 0.25) nanosheets demonstrate greatly improved OER performance than their corresponding hydroxide and oxide counterparts do. From density function theory (DFT) calculations, it is found that the introduction of iron into the pyrite-phased NiP2 alters OER steps occurred on the surface. Notably, the partially oxidized surface of O-Ni(1−x)FexP2 nanosheets is vital to improve the local environment and accelerate the reaction steps. This study sheds light on the OER mechanism of the 3d TMP electrocatalyst and opens up a way to develop efficient and low-cost electrocatalysts

Obvious enhancement of the total reaction cross sections for 27,28^{27,28}P with 28^{28}Si target and the possible relavent mechanisms

The reaction cross sections of $^{27,28}$P and the corresponding isotones on Si target were measured at intermediate energies. The measured reaction cross sections of the N=12 and 13 isotones show an abrupt increase at $$. The experimental results for the isotones with $Z\leq 14$ as well as $$P can be well described by the modified Glauber theory of the optical limit approach. The enhancement of the reaction cross section for $^{28}$P could be explained in the modified Glauber theory with an enlarged core. Theoretical analysis with the modified Glauber theory of the optical limit and few-body approaches underpredicted the experimental data of $^{27}$P. Our theoretical analysis shows that an enlarged core together with proton halo are probably the mechanism responsible for the enhancement of the cross sections for the reaction of $^{27}$P+$^{28}$Si.Comment: 16 pages, 5 figures, to be published in Phys.Rev.

Cochrane systematic reviews on traditional Chinese medicine: What matters-the quantity or quality of evidence?

Systematic reviews on traditional Chinese medicine (TCM) are constantly increasing. However, if these reviews are to be of practical value, the evidence needs to be relevant, valid, and adequately reported. Cochrane Systematic Reviews (CSRs) are considered as high-quality systematic reviews that can inform health care decision making. Our aim was to provide an overview of the scope, findings, quality and impact of CSRs on the benefits and harms associated with TCM interventions for the treatment and prevention of disease to provide new information for clinical practice and future research. The Cochrane Database of Systematic Reviews was searched up to May 2021, and descriptive characteristics were extracted. The correspondence between the questions asked in the CSRs and the available evidence, conclusions and certainty of findings (according to GRADE assessment), methodological quality (AMSTAR 2), and impact (Altmetric Attention Score [AAS], total citations by guideline, and total citations in Web of Science [WoS]) of CSRs were extracted. Tabular and graphical summaries of these descriptive characteristics were constructed. Of 104 CSRs on TCM identified, 70 diseases belonged to 16 disease systems and contained 1642 primary studies with 157,943 participants. Interventions included Chinese herbal medicine (n = 70), acupuncture (n = 28), TCM exercises (n = 4), and moxibustion (n = 2). Among 1642 primary studies, 662 studies included an intervention group treated with at least one TCM therapy and 980 studies included a combination of therapies. Promising outcomes from the 104 CSRs were divided into endpoint outcomes (34 diseases), doctor- or patient-reported outcomes (27 diseases), and surrogate outcomes (37 diseases). Despite the presence of promising outcomes, only 5/104 CSRs drew overall positive conclusions, 42 CSRs concluded the evidence was insufficient, and 54 failed to draw firm conclusions. GRADE assessments were reported in 41.3% of the CSRs, and the ratings were mostly low or very low. Comparing the questions asked and results obtained, there was frequently a lack of information about specific outcomes. Only 16 CSRs obtained results for all outcomes listed in the methods section. According to AMSTAR 2, 51 CSRs (49.0%) were of low quality. The total number of citations in the WoS was 2135 (mean ± SD: 20.8 ± 21.2), and 38.5% of the CSRs had been cited in guidelines 95 times. Although TCM is commonly used, evidence of its effectiveness remains largely inconclusive. Rigorous high-quality trials are needed to support the performance of high-quality reviews and to increase the evidence base. It is critical to emphasize quality over quantity in future TCM research. [Abstract copyright: Copyright © 2022 The Author(s). Published by Elsevier GmbH.. All rights reserved.

Integrabilities of the t−Jt-J Model with Impurities

The hamiltonian with magnetic impurities coupled to the strongly correlated electron system is constructed from $t-J$ model. And it is diagonalized exactly by using the Bethe ansatz method. Our boundary matrices depend on the spins of the electrons. The Kondo problem in this system is discussed in details. The integral equations are derived with complex rapidities which describe the bound states in the system. The finite-size corrections for the ground-state energies are obtained.Comment: 24 pages, Revtex, To be published in J. Phys.

New Frontiers on van der Waals Layered Metal Phosphorous Trichalcogenides

The exponentially growing works on 2D materials have resulted in both high scientific interest and huge potential applications in nanocatalysis, optoelectronics, and spintronics. Of especial note is that the newly emerged and promising family of metal phosphorus trichalcogenides (MPX3) contains semiconductors, metals, and insulators with intriguing layered structures and architectures. The bandgaps of the members in this family range from 1.3 to 3.5 eV, significantly enriching the application of 2D materials in the broad wavelength spectrum. In this review, emphasizing their remarkable structural, physicochemical, and magnetic properties, as well as the numerous applications in various fields, the innovative progress on layered MPX3 crystals is summarized. Different from other layered materials, these crystals will advance a fascinating frontier in magnetism and spintronic devices with their especially featured atomic layered nanosheets. Thus, their crystal and electronic structures, along with some related researches in magnetism, are discussed in detail. The assortments of growth methods are then summarized. Considering their potential applications, the prominent utilization of these 2D MPX3 nanoscrystals in catalysis, batteries, and optoelectronics is also discussed. Finally, the outlook of these kinds of layered nanomaterials is provided

A comprehensive study of the open cluster NGC 6866

We present CCD $UBVRI$ photometry of the field of the open cluster NGC 6866. Structural parameters of the cluster are determined utilizing the stellar density profile of the stars in the field. We calculate the probabilities of the stars being a physical member of the cluster using their astrometric data and perform further analyses using only the most probable members. The reddening and metallicity of the cluster were determined by independent methods. The LAMOST spectra and the ultraviolet excess of the F and G type main-sequence stars in the cluster indicate that the metallicity of the cluster is about the solar value. We estimated the reddening $E(B-V)=0.074 \pm 0.050$ mag using the $U-B$ vs $B-V$ two-colour diagram. The distance modula, the distance and the age of NGC 6866 were derived as $\mu = 10.60 \pm 0.10$ mag, $d=1189 \pm 75$ pc and $t = 813 \pm 50$ Myr, respectively, by fitting colour-magnitude diagrams of the cluster with the PARSEC isochrones. The Galactic orbit of NGC 6866 indicates that the cluster is orbiting in a slightly eccentric orbit with $e=0.12$. The mass function slope $x=1.35 \pm 0.08$ was derived by using the most probable members of the cluster.Comment: 14 pages, including 16 figures and 7 tables, accepted for publication in MNRAS. Table 4 in the manuscript will be published electronicall

Energy level alignment at Alq3/La0.7Sr0.3MnO3 interface for organic spintronic devices

The electronic structure of the interface between Tris (8-hydroxyquinolino)-aluminum (Alq3) and La0.7Sr0.3MnO3 manganite (LSMO) was investigated by means of photoelectron spectroscopy. As demonstrated recently this interface is characterized by efficient spin injection in organic spintronic devices. We detected a strong interface dipole of about 0.9 eV that shifts down the whole energy diagram of the Alq3 with respect to the vacuum level. This modifies the height of the barriers for the holes injection to 1.7 eV, indicating that hole injection from LSMO into Alq3 is more difficult than it was expected as the energy level matched by vacuum levels. We believe the interface dipole is due to the intrinsic dipole moment characteristic for Alq3 layer. An additional weak interaction is observed between the two materials influencing the N 1s core levels of the organic semiconductor. The presented data are of greatest importance for both qualitative and quantitative description of the organic spin valves.Comment: 17 pages, 4 figure

Whole genome resequencing reveals signatures of selection and timing of duck domestication

Background The genetic basis of animal domestication remains poorly understood, and systems with substantial phenotypic differences between wild and domestic populations are useful for elucidating the genetic basis of adaptation to new environments as well as the genetic basis of rapid phenotypic change. Here, we sequenced the whole genome of 78 individual ducks, from two wild and seven domesticated populations, with an average sequencing depth of 6.42X per individual. Results Our population and demographic analyses indicate a complex history of domestication, with early selection for separate meat and egg lineages. Genomic comparison of wild to domesticated populations suggest that genes affecting brain and neuronal development have undergone strong positive selection during domestication. Our FST analysis also indicates that the duck white plumage is the result of selection at the melanogenesis associated transcription factor locus. Conclusions Our results advance the understanding of animal domestication and selection for complex phenotypic traits