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Isospin-symmetry breaking is responsible for the energy difference of excited states in mirror nuclei. It also influences the coefficient of the isobaric multiplet mass equation. In the present work, we extensively investigate isospin-symmetry breaking in medium mass nuclei within ab initio frameworks. For this, we employ the ab initio valence-space in-medium similarity renormalization group approach, in which charge-symmetry and charge-independence breakings are included in the adopted nuclear force. The mirror energies of sd- and pf- shell nuclei are computed for that matter. The effects of single-particle states on weakly bound and unbound nuclear states, especially those of the s-wave, are discussed. Predictions are also made concerning proton drip-line nuclei bearing large mirror energy difference. Finally, the coefficient of the isobaric multiplet mass equation in T = 1/2 and T = 1 isospin multiplets for A = 18 to A = 76 is calculated.

We investigate the pairing properties of state-of-the-art semilocal coordinate-space and semilocal momentum-space regularized chiral interactions. Specifically, we calculate the pairing gaps in $^3SD_1$ channel of symmetric nuclear matter and in $^1S_0$ and $^3PF_2$ channels of pure neutron matter within the BCS approximation using these chiral interactions. We address the regulator and chiral order dependence of the pairing gaps and compare the pairing properties of the chiral interactions with those of the Argonne v18 (Av18) potential. The effects of the tensor force on the pairing gaps in the $^3SD_1$ and $^3PF_2$ channels are illustrated for both the chiral interactions and the Av18 potential. We evaluate the truncation errors of chiral expansions of the pairing gaps with a Bayesian approach. We find that the pairing gaps converge very well at the higher-order chiral expansions in the $^3SD_1$ and $^1S_0$ channels.

$\alpha$-decay always has enormous impetuses to the development of physics and chemistry, in particular due to its indispensable role in the research of new elements. Although it has been observed in laboratories for more than a century, it remains a difficult problem to calculate accurately the formation probability $S_\alpha$ microscopically. To this end, we establish a new model, i.e., multistep model, and the corresponding formation probability $S_\alpha$ values of some typical $\alpha$-emitters are calculated without adjustable parameters. The experimental half-lives, in particular their irregular behavior around a shell closure, are remarkably well reproduced by half-life laws combined with these $S_\alpha$. In our strategy, the cluster formation is a gradual process in heavy nuclei, different from the situation that cluster pre-exists in light nuclei. The present study may pave the way to a fully understanding of $\alpha$-decay from the perspective of nuclear structure., Comment: 7 pages, 4 figures

Fine structure in the $��$ decay of $^{223}$U was observed in the fusion-evaporation reaction $^{187}$Re($^{40}$Ar, p3n) by using fast digital pulse processing technique. Two $��$-decay branches of $^{223}$U feeding the ground state and 244 keV excited state of $^{219}$Th were identified by establishing the decay chain $^{223}$U $\xrightarrow{��_{1}}$ $^{219}$Th $\xrightarrow{��_{2}}$ $^{215}$Ra $\xrightarrow{��_{3}}$ $^{211}$Rn. The $��$-particle energy for the ground-state to ground-state transition of $^{223}$U was determined to be 8993(17) keV, 213 keV higher than the previous value, the half-life was updated to be 62$^{+14}_{-10}$ $��$s. Evolution of nuclear structure for $N$ = 131 even-$Z$ isotones from Po to U was discussed in the frameworks of nuclear mass and reduced $��$-decay width, a weakening octupole deformation in the ground state of $^{223}$U relative to its lighter isotones $^{219}$Ra and $^{221}$Th was suggested., 6 pages, 6 figures

© 2017 This material is published with the support of the US Department of Energy under Contract No. DE-EE0007688. Fast simulation for stratified indoor airflow distributions is desired for various applications, such as design of advanced indoor environments, emergency management, and coupled annual energy simulation for buildings with stratified air distributions. Reduced order models trained by pre-computed computational fluid dynamics results are fast, but their prediction may be inaccurate when applied for conditions outside the training domain. To overcome this limitation, we propose a fast and self-learning model based on an in situ adaptive tabulation (ISAT) algorithm, which is trained by a fast fluid dynamics (FFD) model as an example. The idea is that the ISAT will retrieve the solutions from an existing data set if the estimated prediction error is within a pre-defined tolerance. Otherwise, the ISAT will execute the FFD simulation, which is accelerated by running in parallel on a graphics processing unit, for a full-scale simulation. This paper systematically investigates the feasibility of the ISAT for indoor airflow simulations by presenting the ISAT-FFD implementation alongside results related to its overall performance. Using a stratified indoor airflow as an example, we evaluated how the training time of ISAT was impacted by four factors (training methods, error tolerances, number of inputs, and number of outputs). Then we demonstrated that a trained ISAT model can predict the key information for inputs both inside and outside the training domain. The ISAT was able to answer query points both inside and close to training domain using retrieve actions within a time less than 0.001 s for each query. Finally, we provided suggestions for using the ISAT for building applications.

We present a novel deep learning approach to synthesize complete face images in the presence of large ocular region occlusions. This is motivated by recent surge of VR/AR displays that hinder face-to-face communications. Different from the state-of-the-art face inpainting methods that have no control over the synthesized content and can only handle frontal face pose, our approach can faithfully recover the missing content under various head poses while preserving the identity. At the core of our method is a novel generative network with dedicated constraints to regularize the synthesis process. To preserve the identity, our network takes an arbitrary occlusion-free image of the target identity to infer the missing content, and its high-level CNN features as an identity prior to regularize the searching space of generator. Since the input reference image may have a different pose, a pose map and a novel pose discriminator are further adopted to supervise the learning of implicit pose transformations. Our method is capable of generating coherent facial inpainting with consistent identity over videos with large variations of head motions. Experiments on both synthesized and real data demonstrate that our method greatly outperforms the state-of-the-art methods in terms of both synthesis quality and robustness., Comment: 12 pages,9 figures

© 2017 IEEE. This paper reviews the first challenge on single image super-resolution (restoration of rich details in an low resolution image) with focus on proposed solutions and results. A new DIVerse 2K resolution image dataset (DIV2K) was employed. The challenge had 6 competitions divided into 2 tracks with 3 magnification factors each. Track 1 employed the standard bicubic downscaling setup, while Track 2 had unknown downscaling operators (blur kernel and decimation) but learnable through low and high res train images. Each competition had b∼100 registered participants and 20 teams competed in the final testing phase. They gauge the state-of-the-art in single image super-resolution.

Background: Neuraminidase inhibitors were widely used during the 2009-10 influenza A H1N1 pandemic, but evidence for their effectiveness in reducing mortality is uncertain. We did a meta-analysis of individual participant data to investigate the association between use of neuraminidase inhibitors and mortality in patients admitted to hospital with pandemic influenza A H1N1pdm09 virus infection. Methods: We assembled data for patients (all ages) admitted to hospital worldwide with laboratory confirmed or clinically diagnosed pandemic influenza A H1N1pdm09 virus infection. We identified potential data contributors from an earlier systematic review of reported studies addressing the same research question. In our systematic review, eligible studies were done between March 1, 2009 (Mexico), or April 1, 2009 (rest of the world), until the WHO declaration of the end of the pandemic (Aug 10, 2010); however, we continued to receive data up to March 14, 2011, from ongoing studies. We did a meta-analysis of individual participant data to assess the association between neuraminidase inhibitor treatment and mortality (primary outcome), adjusting for both treatment propensity and potential confounders, using generalised linear mixed modelling. We assessed the association with time to treatment using time-dependent Cox regression shared frailty modelling. Findings: We included data for 29234 patients from 78 studies of patients admitted to hospital between Jan 2, 2009, and March 14, 2011. Compared with no treatment, neuraminidase inhibitor treatment (irrespective of timing) was associated with a reduction in mortality risk (adjusted odds ratio [OR] 0·81; 95% CI 0·70-0·93; p=0·0024). Compared with later treatment, early treatment (within 2 days of symptom onset) was associated with a reduction in mortality risk (adjusted OR 0·48; 95% CI 0·41-0·56; p

A recent proposed method for $��$-decay energies ($Q_��$) [J.M. Dong, W. Zuo, and W. Scheid, Phys. Rev. Lett. \textbf{107}, 012501 (2011)] can reproduce experimental data of superheavy nuclei (SHN) with an $rms$-value of less than 100 keV. However, a sinusoid-like periodic deviation from experiments, which limits the accuracy in predictions, is observed when using different reference nuclei. In this paper, we have further extended this hybrid method, i.e., to predict $Q_��$ of the as-yet-unobserved SHN with the help of known nuclei. It is found that the systematic deviation in previous study is rooted in the nuclear mass model employed. By further analyzing the source of errors, different nuclear mass models are evaluated based on the same procedure., 9 pages, 3 figures

We investigate the $^1S_0$ neutron and proton superfluidity in isospin asymmetric nuclear matter. We have concentrated on the isospin dependence of the pairing gaps and the effect of a microscopic three-body force. It is found that as the isospin asymmetry goes higher, the neutron $^1S_0$ superfluid phase shrinks gradually to a smaller density domain, while the proton one extends rapidly to a much wider density domain. The three-body force turns out to weaken the neutron $^1S_0$ superfluidity slightly, but it suppresses strongly the proton $^1S_0$ superfluidity at high densities in nuclear matter with large isospin asymmetry., Comment: 12 pages, 2 figures

© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim In perovskite solar cells (PSCs), the interfaces are a weak link with respect to degradation. Electrochemical reactivity of the perovskite's halides has been reported for both molecular and polymeric hole selective layers (HSLs), and here it is shown that also NiO brings about this decomposition mechanism. Employing NiO as an HSL in p–i–n PSCs with power conversion efficiency (PCE) of 16.8%, noncapacitive hysteresis is found in the dark, which is attributable to the bias-induced degradation of perovskite/NiO interface. The possibility of electrochemically decoupling NiO from the perovskite via the introduction of a buffer layer is explored. Employing a hybrid magnesium-organic interlayer, the noncapacitive hysteresis is entirely suppressed and the device's electrical stability is improved. At the same time, the PCE is improved up to 18% thanks to reduced interfacial charge recombination, which enables more efficient hole collection resulting in higher Voc and FF.

With the expansion of data, increasing imbalanced data has emerged. When the imbalance ratio of data is high, most existing imbalanced learning methods decline in classification performance. To address this problem, a few highly imbalanced learning methods have been presented. However, most of them are still sensitive to the high imbalance ratio. This work aims to provide an effective solution for the highly imbalanced data classification problem. We conduct highly imbalanced learning from the perspective of feature learning. We partition the majority class into multiple blocks with each being balanced to the minority class and combine each block with the minority class to construct a balanced sample set. Multiset feature learning (MFL) is performed on these sets to learn discriminant features. We thus propose an uncorrelated cost-sensitive multiset learning (UCML) approach. UCML provides a multiple sets construction strategy, incorporates the cost-sensitive factor into MFL, and designs a weighted uncorrelated constraint to remove the correlation among multiset features. Experiments on five highly imbalanced datasets indicate that: UCML outperforms state-of-the-art imbalanced learning methods.

Aims: This study is to retrospectively analyze the clinical and pathological data of six cases of primary nasal clear cell carcinoma in our hospital since 1992 and to review literatures on the clinical manifestations, pathological features, immunohistochemistry, diagnosis and treatment of the disease. Methods: The pathological archives that were diagnosed as salivary gland nasal tumors in Shandong Cancer Hospital during 1992-2013 were reviewed. Careful review of sections was performed by two experienced pathologists. The samples were labeled using EnVision method. Immunostaining was performed using 3, 3’-diaminobenzidine reagent followed by counterstaining with hematoxylin. The immunohistochemical results were classified according to positive cells: no positive staining cells (-); positive cells 50% (+++). Results: Among the 6 cases of primary nasal clear cell carcinoma in our hospital since 1992, 4 cases were diagnosed as clear cell carcinoma of nasal cavity after exclusion of other nasal cavity tumors with clear cells, and 2 cases were directly diagnosed as clear cell carcinoma of nasal cavity. Hyalinizing clear cell carcinoma of salivary gland (HCCC) tissues were mainly composed of polygonal epithelioid tumor cells arranged into the shapes of beehives, and separated by fibrous tissues containing rich thin-wall capillaries. The cytoplasm of HCCC cells was rich and translucent with some cells having multiple vacuoles. Reticular fiber staining showed that the tumor cells were arranged in shapes of beehives and separated by rich reticular fibers. HCCC tumor reacted differently on S-100 protein, glial fibrillary acidic protein, actin and vimentin. The ultrastructure of HCCC cells showed characteristics of ducts but no myoepithelial differentiation. Conclusions: This study demonstrates that correct diagnosis, timely surgical resection and postoperative radiotherapy are effective in treating nasal clear cell carcinoma.

Tin halide perovskites attract incremental attention to deliver lead free perovskite solar cells. Nevertheless, disordered crystal growth and low defect formation energy, related to Sn II oxidation to Sn IV , limit the efficiency and stability of solar cells. Engineering the processing from perovskite precursor solution preparation to film crystallization is crucial to tackle these issues and enable the full photovoltaic potential of tin halide perovskites. Herein, the ionic liquid n butylammonium acetate BAAc is used to tune the tin coordination with specific O Sn chelating bonds and N amp; 63743;H X hydrogen bonds. The coordination between BAAc and tin enables modulation of the crystallization of the perovskite in a thin film. The resulting BAAc containing perovskite films are more compact and have a preferential crystal orientation. Moreover, a lower amount of Sn IV and related chemical defects are found for the BAAc containing perovskites. Tin halide perovskite solar cells processed with BAAc show a power conversion efficiency of over 10 . This value is retained after storing the devices for over 1000 h in nitrogen. This work paves the way toward a more controlled tin based perovskite crystallization for stable and efficient lead free perovskite photovoltaics

Low toxicity and an ideal energy bandgap make two-dimensional (2D) Ruddlesden–Popper tin-based halide perovskites a promising photovoltaic material. However, the disordered crystal orientation and the oxidation of Sn2+ to Sn4+ still need to be addressed. Here, we demonstrate that the annealing of FASnI3 assisted by phenyl ethylammonium chloride enables the formation of more ordered 2D tin-based perovskite crystals oriented vertically. We use in situ synchrotron-based grazing incident X-ray diffraction to correlate the higher crystal orientation to the better device performance. We measured a maximum power conversion efficiency of more than 9%. Furthermore, we demonstrate that the phenyl ethylammonium chloride acts as a barrier layer at the surface of the crystals protecting the tin from the oxidation. Hence, this work paves the way for more efficient and stable lead-free perovskite solar cells.

Mixed cation halide perovskites have led to a significant increase in the efficiency and stability of perovskite solar cells. However, mobile ionic defects inevitably exacerbate the photoinduced phase segregation and self decomposition of the crystal structure. Herein, ultrathin two dimensional nanosheets of oxo functionalized graphene dodecylamine oxo G DA are used to solve ion migration in cesium Cs formamidinium FA methylammonium MA triple cation base perovskites. Based on the superconducting carbon skeleton and functional groups that provide lone pairs of electrons on it, the ultra thin two dimensional network structure can tight fit on the crystals and wrap them, isolate them and thus reduce the migration of ions within the built in electric field of the perovskite film. As evidence of the formation of sharp crystals with different orientation within the perovskite film, we observed moir fringes in transmission electron microscopy. Thus, we report a champion device with a power conversion efficiency PCE of 21.1 the efficiencies distribution is 18.8 1.7 , and a remarkable fill factor of 81 , with reduced hysteresis and improved long term stability. This work provides a simple method for the improvement of the structural stability of perovskite in solar cells