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Interactions of collective excitations often lead to rich emergent phenomena in many-particle quantum systems. In ordered magnets, the elementary excitations are spin waves (magnons), which obey Bose-Einstein statistics. Similar to the Cooper pairs in superconductors, magnons can be paired into bound states under attractive interactions. Even more interestingly, the Zeeman coupling to a magnetic field acts as a chemical potential that can tune the particle density through a quantum critical point (QCP), beyond which a ``hidden order'' is predicted to exist. However, experimental confirmation of this QCP and the associated new state of matter remain elusive. Here we report direct observation of the Bose-Einstein condensation (BEC) of the two-magnon bound state in Na$_2$BaNi(PO$_4$)$_2$. Comprehensive thermodynamic measurements confirmed the existence of a two-dimensional BEC-QCP at the saturation field. Inelastic neutron scattering experiments were performed to accurately establish the magnetic exchange model. An exact solution of the model found stable 2-magnon bound states that were further confirmed by an electron spin resonance (ESR) experiment, demonstrating that the QCP is due to the pair condensation and the phase below saturation field is the long-sought-after spin nematic (SN) phase., 53 pages, 28 figures

The past three decades have witnessed notable success in designing efficient SAT solvers, with modern solvers capable of solving industrial benchmarks containing millions of variables in just a few seconds. The success of modern SAT solvers owes to the widely-used CDCL algorithm, which lacks comprehensive theoretical investigation. Furthermore, it has been observed that CDCL solvers still struggle to deal with specific classes of benchmarks comprising only hundreds of variables, which contrasts with their widespread use in real-world applications. Consequently, there is an urgent need to uncover the inner workings of these seemingly weak yet powerful black boxes. In this paper, we present a first step towards this goal by introducing an approach called CausalSAT, which employs causal reasoning to gain insights into the functioning of modern SAT solvers. CausalSAT initially generates observational data from the execution of SAT solvers and learns a structured graph representing the causal relationships between the components of a SAT solver. Subsequently, given a query such as whether a clause with low literals blocks distance (LBD) has a higher clause utility, CausalSAT calculates the causal effect of LBD on clause utility and provides an answer to the question. We use CausalSAT to quantitatively verify hypotheses previously regarded as "rules of thumb" or empirical findings such as the query above. Moreover, CausalSAT can address previously unexplored questions, like which branching heuristic leads to greater clause utility in order to study the relationship between branching and clause management. Experimental evaluations using practical benchmarks demonstrate that CausalSAT effectively fits the data, verifies four "rules of thumb", and provides answers to three questions closely related to implementing modern solvers., 17 pages, 3 figures, to be published in SAT23

The problem of model counting, also known as #SAT, is to compute the number of models or satisfying assignments of a given Boolean formula $F$. Model counting is a fundamental problem in computer science with a wide range of applications. In recent years, there has been a growing interest in using hashing-based techniques for approximate model counting that provide $(\varepsilon, \delta)$-guarantees: i.e., the count returned is within a $(1+\varepsilon)$-factor of the exact count with confidence at least $1-\delta$. While hashing-based techniques attain reasonable scalability for large enough values of $\delta$, their scalability is severely impacted for smaller values of $\delta$, thereby preventing their adoption in application domains that require estimates with high confidence. The primary contribution of this paper is to address the Achilles heel of hashing-based techniques: we propose a novel approach based on rounding that allows us to achieve a significant reduction in runtime for smaller values of $\delta$. The resulting counter, called RoundMC, achieves a substantial runtime performance improvement over the current state-of-the-art counter, ApproxMC. In particular, our extensive evaluation over a benchmark suite consisting of 1890 instances shows that RoundMC solves 204 more instances than ApproxMC, and achieves a $4\times$ speedup over ApproxMC., Comment: 18 pages, 3 figures, to be published in CAV23

Aliovalent doping has been adopted to optimize the electrical properties of semiconductors, while its impact on the phonon structure and propagation is seldom paid proper attention to. This work reveals that aliovalent doping can be much more effective in reducing the lattice thermal conductivity of thermoelectric semiconductors than the commonly employed isoelectronic alloying strategy. As demonstrated in the heavy-band NbFeSb system, a large reduction of 65% in the lattice thermal conductivity is achieved through only 10% aliovalent Hf-doping, compared to the 4 times higher isoelectronic Ta-alloying. It is elucidated that aliovalent doping introduces free charge carriers and enhances the screening, leading to the giant softening and deceleration of optical phonons. Moreover, the heavy dopant can induce the avoided-crossing of acoustic and optical phonon branches, further decelerating the acoustic phonons. These results highlight the significant role of aliovalent dopants in regulating the phonon structure and suppressing the phonon propagation of semiconductors.

The health beliefs and practices regarding cervical cancer screening among women in the mountainous and Terai region of Nepal were investigated and examined for the differences. A descriptive cross-sectional study was conducted with a purposive sample of 216 in mountainous and 294 in Terai. The interview tools were a socio-demographic scale, a Nepalese Health Belief Model Scale for Cervical Cancer followed by the Screening Test. Chi-square test, binary logistic regression, Mann-Whitney U, and Kruskal-Wallis were used to analyze the data. The results showed that the screening rate was low for both regions with a significant difference in the benefit of screening and health motivation. Being older and having a positive family history of cervical cancer were shown to be predictors screening practice. Women from both groups preferred female doctors for screening. Culturally appropriate educational interventions focused on the benefits and obstacles of screening is needed to improve the beliefs of cervical cancer and screening and increase the screening rate. Nurses need to be aware of health beliefs regarding cervical cancer during cervical screening and education.

Despite the NP-completeness of Boolean satisfiability, modern SAT solvers are routinely able to handle large practical instances, and consequently have found wide ranging applications. The primary workhorse behind the success of SAT solvers is the widely acclaimed Conflict Driven Clause Learning (CDCL) paradigm, which was originally proposed in the context of Boolean formulas in CNF. The wide ranging applications of SAT solvers have highlighted that for several domains, CNF is not a natural representation and the reliance of modern SAT solvers on resolution proof system limit their ability to efficiently solve several families of constraints. Consequently, the past decade has witnessed the design of solvers with native support for constraints such as Pseudo-Boolean (PB) and CNF-XOR. The primary contribution of our work is an efficient solver engineered for PB-XOR formulas, i.e., formulas consisting of a conjunction of PB and XOR constraints. We first observe that a simple adaption of CNF-XOR architecture does not provide an improvement over baseline; our analysis highlights the need for careful engineering of the order of propagations. To this end, we propose three different tactics, all of which achieve significant performance improvements over the baseline. Our work is motivated by applications arising from binarized neural network verification where the verification of properties such as robustness, fairness, trojan attacks can be reduced to model counting queries; the state of the art model counters reduce counting to polynomially many SAT queries over the original formula conjuncted with randomly generated XOR constraints. To this end, we augment ApproxMC with LinPB and we call the resulting counter as ApproxMCPB. In an extensive empirical comparison over 1076 benchmarks, we observe that ApproxMCPB can solve 912 instances while the baseline version of ApproxMC4 (augmented with CryptoMiniSat) can solve only 802 instances., LIPIcs, Vol. 210, 27th International Conference on Principles and Practice of Constraint Programming (CP 2021), pages 58:1-58:20

The past decade has witnessed a surge of interest in practical techniques for projected model counting. Despite significant advancements, however, performance scaling remains the Achilles' heel of this field. A key idea used in modern counters is to count models projected on an \emph{independent support} that is often a small subset of the projection set, i.e. original set of variables on which we wanted to project. While this idea has been effective in scaling performance, the question of whether it can benefit to count models projected on variables beyond the projection set, has not been explored. In this paper, we study this question and show that contrary to intuition, it can be beneficial to project on variables beyond the projection set. In applications such as verification of binarized neural networks, quantification of information flow, reliability of power grids etc., a good upper bound of the projected model count often suffices. We show that in several such cases, we can identify a set of variables, called upper bound support (UBS), that is not necessarily a subset of the projection set, and yet counting models projected on UBS guarantees an upper bound of the true projected model count. Theoretically, a UBS can be exponentially smaller than the smallest independent support. Our experiments show that even otherwise, UBS-based projected counting can be more efficient than independent support-based projected counting, while yielding bounds of very high quality. Based on extensive experiments, we find that UBS-based projected counting can solve many problem instances that are beyond the reach of a state-of-the-art independent support-based projected model counter.

In the palletizing task, the three-dimensional size of the stack directly affects the working distance (i.e., depth) of the manipulator in the Z-axis direction. In order to complete the palletizing task accurately and reliably and realize human-computer interaction, it is necessary to obtain the three-dimensional structural characteristics of the pallet in real time. Therefore, this paper proposes a three-dimensional reconstruction of the single image of the grab based on the palletizing task. Firstly this paper converts the RGB image of the stack to a grayscale image, then uses the Canny method to detect the edge of the corresponding grayscale image, and uses the Hough line detection algorithm to extract the straight line in the edge image. By analyzing the characteristics of the straight line cluster. A stack is divided into three groups of straight lines in the horizontal, vertical, and vertical directions according to the angle characteristics of the straight line. The RANSAC algorithm is used to analyze and obtain the best linear model of the straight line in each direction. And the minimum distance method is used to solve the vanishing points in the three directions of horizontal, vertical and vertical, and then the internal and external parameters of the camera are calibrated according to the attributes of the vanishing points. A fast and high-precision rectangle detection algorithm is used to detect the coordinates of the vertices of the cuboid. In particular, the size of each cuboid part is consistent and known, so this paper combines the camera’s internal and external parameters with the geometric characteristics of the stack can get the length, width, and height and visual model of a real-time changing stack during the palletizing task. The experimental results show that this algorithm can well build a three-dimensional wireframe model of the stack, and realize the three-dimensional visualization of the model. The maximum error of the reconstructed model is 0.950, the minimum error is 0, and the average error is 0.217; the maximum length The error is 0.560, the minimum error is 0, and the average error is 0.187; the maximum error of the width is 0.950, the minimum error is 0.064, and the average error is 0.461; the maximum error of the height is 0.420, the minimum error is 0, and the average error is 0.14; the robot Z axis The maximum error of the working distance (i.e. depth) in the direction is 0.24, the minimum error is 0, and the average error is 0.08, which meets our actual modeling requirements.

Additive manufacturing is a relevant technology for tissue engineering applications. However, due to some limitations in terms of the printing heads being used it is difficult to create complex multi-material hierarchical structures resembling natural tissues. The combination of 3D printing and microfluidics has the potential to overcome these limitations allowing to engineer functional artificial tissues with complex architectures. To achieve this a novel negative protrusion compression co-axial nozzle with a small expanding chamber is proposed in this paper, allowing balanced fluid flow conditions and uniform core-shell fibers., Transactions on Additive Manufacturing Meets Medicine, Vol 2 No 1 (2020): Trans. AMMM

Interleukin-13 plays a critical role in mediating many biological processes responsible for allergic inflammation. Mast cells express Il13 mRNA and produce IL-13 protein in response to antigenic stimulation. Enhancers are essential in promoting gene transcription and are thought to activate transcription by delivering essential accessory co-factors to the promoter to potentiate gene transcription. However, enhancers mediating Il13 have not been identified. Furthermore, which Il13 enhancers detect signals triggered by antigenic stimulation have not yet been defined. In this study, we identified potential mouse Il13 enhancers using histone modification monomethylation at lysine residue 4 on histone 3 (H3K4me1) ChIP-seq and acetylation at lysine residue 27 on histone 3 (H3K27ac) ChIP-seq. We used Omni-ATAC-seq to determine which accessible regions within the potential Il13 enhancers that responded to IgE receptor crosslinking. We also demonstrated that the transcription factor (TF) cluster consisting of the NFATC2, STAT5, GATA2, AP1, and RUNX1 binding sites at the proximal Il13 enhancer, the TF cluster consisting of the EGR2-binding site at the distal Il13 E+6.5 enhancer, are critical in sensing the signals triggered by antigenic stimulation. Those enhancers, which are responsive to antigenic stimulation and constitutively active, cooperate to generate greater transcriptional outputs. Our study reveals a novel mechanism underlying how antigenic stimulation induces robust Il13 mRNA expression in mouse mast cells.

Wei Jiang,1 Xiaofei Deng,1 Ting Zhu,1 Yuya Wei,1 Zhen Lei,1 Meimei Guo,2 Jiong Yang2 1Department of Ultrasound, Huazhong University of Science and Technology Union Shenzhen Hospital, Shenzhen 518052, People’s Republic of China; 2Department of Gastroenterology, Huazhong University of Science and Technology Union Shenzhen Hospital, Shenzhen 518052, People’s Republic of ChinaCorrespondence: Wei JiangDepartment of Ultrasound, Shenzhen Nanshan District People’s Hospital, No. 89, Taoyuan Road, Nanshan District, Shenzhen 518052, People’s Republic of ChinaTel +86 13026628099Email jwszdr@126.comBackground: Identification of cholangiocarcinoma (CCA) associated with hepatolithiasis (HL) is difficult. There is no effective method to discriminate CCA associated with HL (HL-CCA) from HL currently.Objective: To explore the value of clinical data, ultrasonic characteristics and miRNA expression level in the identification of HL-CCA.Methods: Thirty-one patients with HL-CCA in Huazhong University of Science and Technology Union Shenzhen Hospital were enrolled in the observation group, while 40 patients with HL alone were included in the control group. The clinical data, ultrasonic characteristics, and miRNA expression level of the two groups were recorded and analyzed to explore the potential indicators for the identification of HL-CCA.Results: The accuracy of ultrasound in the diagnosis of HL-CCA was low (54.84%). Multivariate logistic regression analysis showed that liver abscess (P=0.021), indistinct border demarcation (P=0.015), non-homogenous echotexture (P=0.019), missed portal vein around lesion (P=0.032), miRNA-21 (P=0.018) and miRNA-221 (P=0.009) were the potential indicators for the identification of HL-CCA. The combined diagnosis based on logistic regression contained liver abscess, border demarcation, echotexture, portal vein around lesion, miRNA-21 and miRNA-221. The results showed that the accuracy of combined diagnosis identifying HL-CCA was the most accurate (AUC=0.911), which was significantly greater than the AUC of miRNA-21 or miRNA-221 individually (P< 0.05), with a sensitivity and specificity of 77.42% and 97.50%, respectively.Conclusion: Patients with HL-CCA show high incidence of hepatic abscess and elevated miRNA-21 and miRNA-221 expression level. The ultrasonic features are more likely to show indistinct border demarcation, non-homogenous echotexture, and missed portal vein around lesion. The combined diagnosis is more accurate in the identification of HL-CCA.Keywords: cholangiocarcinoma, hepatolithiasis, microRNA, differential diagnosis, combined diagnosis, ultrasound

Taking advantages of both azide and cyanide bridges in magnetism and synthesis, an azido–cyanide mixed-bridged octanuclear [FeIII4NiII4] SMM of [{(enbzpy)Ni2(μ1,1-N3)2·(DMF)}{Tp*Fe(CN)3}2]2·2DMF·14...

Rechargeable aqueous Zn-ion batteries (ZIBs) are very promising for large-scale grid energy storage applications owing to their low cost, environmentally benign constituents, excellent safety, and relatively high energy density. Their usage, however, is largely hampered by the fast capacity fade. The complexity of the reactions has resulted in long-standing ambiguities of the chemical pathways of Zn/MnO 2 system. In this study, we find that both H + /Zn 2+ intercalation and conversion reactions occur at different voltages and that the rapid capacity fading can clearly be ascribed to the rate-limiting and irreversible conversion reactions at a lower voltage. By limiting the irreversible conversion reactions at â1.26 V, we successfully demonstrate ultrahigh power and long life that are superior to most of the reported ZIBs or even some lithium-ion batteries.

Tao Wang,1,* Yifei Chen,1,* Hanxiang Nie,2 Yi Huang,2 Yang Zhao,2 Jiong Yang1 1Department of Respiratory and Critical Care Medicine, Zhongnan Hospital of Wuhan University, Wuhan, Hubei, China; 2Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China *These authors contributed equally to this work Introduction: Non-small-cell lung cancer (NSCLC) accounts for more than half of all lung cancer cases. Cytokines play an important role in NSCLC, including IL-27. IL-27 inhibits NSCLC progression; however, the mechanism is not clear. The purpose of this study is to investigate the effects of IL-27 on NSCLC cell proliferation and metastasis. Materials and methods: NSCLC cells were treated with IL-27 or transfected with miR-935, and the cell proliferation was assayed by Cell Counting Kit-8 (CCK-8) and colony formation. Cell metastasis was analyzed by Transwell chamber system and wound healing assay. IL-27 protein in the medium was analyzed by ELISA. IL-27 mRNA expression was measured by quantitative reverse transcriptase-PCR. Results: We found that IL-27 played an inhibiting role in NSCLC cell proliferation and metastasis. The molecular mechanism of the suppressing role of IL-27 in NSCLC was regulated by miR-935. IL-27 expression was negatively associated with miR-935 in the clinical NSCLC samples. Conclusion: The study revealed that IL-27 decreased lung cancer cell proliferation and metastasis via miR-935. Keywords: non-small cell lung cancer, IL-27, miR-935

A medical school in China engaged in reform in 2009 by adapting the medical curriculum of the University of Chicago, USA. Freshmen volunteered for the reform and 50 were randomly selected while the rest remained in the traditional curriculum. In 2014 a study was conducted to determine whether the views of traditional and reform curriculum students on their respective educational experience differed and to identify reform areas that needed improvement. A survey was administered to graduating students to gauge their views on basic science and clinical science education, clerkships, general medical education, and readiness for residency training. Frequency distributions, Mann-Whitney U tests, and Chi-squared tests were used for analysis. Reform curriculum students were more positive about their basic science and clinical science instruction. Clerkships were only somewhat satisfactory to students in both curricula. Reform curriculum students were more likely than those following the traditional curriculum to consider instruction in clinical decision-making and patient care as ‘adequate’. Instruction in population health was considered inadequate by the majority of students. Reform curriculum students were more confident about their preparedness for residency. The traditional curriculum was in need of reform. Reform has been effectively implemented and has increased student confidence and satisfaction with their education although there is room for improvement.

Over the last decade, with the popularization of camera-equipped devices, there has been an explosive growth of video data. Despite the diverse visual contents, there are usually some thematic objects in these videos. As the key objects to be presented, thematic objects appear frequently and occupy highlighted positions in the video scenes, thus retain our impression after watching the videos, such as the bride and the groom in wedding ceremony videos, the birthday girl in birthday party videos, or product logo in commercial videos. Automatically discovering and localizing these thematic objects can benefit many real-world applications, such as video summarization, search, and labeling. However, this task is challenging as there is no prior information or initialization about the thematic objects. Moreover, there is usually background clutter, occlusions, or camera motions accompanying the targets. In this thesis, a systematic study is conducted on the automatic discovery and localization of thematic objects in videos. We have studied this problem under various settings, including automatic discovery and localization of the thematic object in single videos, automatic discovery and segmentation of the thematic object in single videos, and automatic thematic action discovery and localization in collections of videos. In the absence of category-specific supervision and manual initialization, various category-independent cues have been explored to discover and localize the thematic objects. These include the spatiotemporal saliency to highlight regions with salient appearance or motion with respect to the background, temporal smoothness of spatial locations and appearance variations along the object moving trajectory, and global appearance consistency of the object throughout its presence. When the discovery is performed in video collections instead of single videos, the semantic similarities in terms of appearance and/or motion patterns of the objects between different videos are also important. Novel techniques are proposed in this thesis to improve the reliability and efficiency of these cues as well as how they can be better explored to improve the discovery and localization performance. Extensive evaluations on both benchmarking as well as newly proposed datasets demonstrate the usefulness of these proposed methods as well as their superiority over existing approaches. Doctor of Philosophy (IGS)

Two-dimensional (2D) monolayer phosphorene, a 2D system with quasi-one-dimensional (quasi-1D) excitons, provides a unique 2D platform for investigating the dynamics of excitons in reduced dimensions and fundamental many-body interactions. However, on the other hand, the quasi-1D excitonic nature can limit the luminescence quantum yield significantly. Here, we report exciton brightening in monolayer phosphorene achieved via the dimensionality modification of excitons from quasi-1D to zero-dimensional (0D), through the transference of monolayer phosphorene samples onto defect-rich oxide substrate deposited by plasma-enhanced chemical vapor deposition (PECVD). The resultant interfacial luminescent local states lead to exciton localization and trigger efficient photon emissions at a new wavelength of ~920 nm. The luminescence quantum yield of 0D-like localized excitons is measured to be at least 33.6 times larger than that of intrinsic quasi-1D free excitons in monolayer phosphorene. This is primarily due to the reduction of non-radiative decay rate and the possibly enhanced radiative recombination probability. Owing to the large trapping energy, this new photon emission from the localized excitons in monolayer phosphorene can be observed at elevated temperature, which contrasts markedly with defect-induced photon emission from transition metal dichalcogenide (TMD) semiconductor monolayers that can only be observed at cryogenic temperatures. Our findings introduce new avenues for the development of novel photonic devices based on monolayer phosphorene, such as near-infrared lighting devices that are operable at elevated temperature. More importantly, 2D phosphorene with quasi-1D free excitons and 0D-like localized excitons provides a unique platform to investigate the fundamental phenomena in the ideal 2D-1D-0D hybrid system.

The resistance of the anodic PbO film formed on lead at 0.9 V (vs. Hg/Hg2SO4) in 4.5 mol/dm3 H2SO4 was measured using alternating-current impedance method. The resistance of the anodic PbO film was found to be close to that of the interstitial liquid among the PbO particles in the film, suggesting mat the interstitial liquid may serve as the major passage for ion transportation during the film growth.

Filled skutterudite is a typical thermoelectric material with high thermoelectric figure of merit at intermediate temperatures. One of the important features is the low lattice thermal conductivity (L) caused by the low frequency vibrations of filler atoms in the oversized void cages. In the past decades, it has been still under debate whether the underlying phonon scattering mechanism should be considered to be resonant scattering or enhanced three-phonon process. To clarify the role played by the filler atoms in reducing the lattice thermal conductivity, we study the microscopic dynamical process of filler and related interactions by means of ab initio molecular dynamics (AIMD) and temperature dependent effective potential (TDEP) technique. Firstly, we simulate the dynamical trajectories of fully filled skutterudite YbFe4Sb12 at different temperatures through AIMD. In this approach, the nonlinear guest-host interactions at finite temperatures are taken into consideration naturally from dynamical trajectories. Then, we extract the effective temperature-dependent harmonic and anharmonic interatomic force constants (IFCs) by TDEP method through the statistical analyses of both trajectories and forces. The atomic participation ratios and lifetimes of phonon modes are calculated based on the effective IFCs. The results demonstrate that the local vibration modes of Yb couple with acoustic branches and reduce the lifetimes of the lattice phonons significantly. However, the calculated L, which is on the assumption that the filler interacts with lattice phonons through three-phonon collision, still deviates from the experimental result. In order to rationalize the discrepancy, we analyze the correlation properties between different Yb atoms by velocity coherence in atomic dynamical motions. The localized and independent vibration characteristic of Yb is found in this analysis. This implies that the motions of Yb atoms deviate from the periodic and collective vibration excitation paradigm of phonon. Therefore, the mechanism for how filler atoms scatter lattice phonon and enhance thermal resistance is beyond three-phonon scattering process. We thus introduce resonant scattering into the lifetimes of Yb-dominant localized vibration modes, and so-calculated L is in a good agreement with the experimental data. Overall, we come to a conclusion that both the phonon-phonon interaction and the resonant scattering due to the localized oscillators cause the low lattice thermal conductivity of YbFe4Sb12.

Monolayer phosphorene provides a unique two-dimensional (2D) platform to investigate the fundamental dynamics of excitons and trions (charged excitons) in reduced dimensions. However, owing to its high instability, unambiguous identification of monolayer phosphorene has been elusive. Consequently, many important fundamental properties, such as exciton dynamics, remain underexplored. We report a rapid, noninvasive, and highly accurate approach based on optical interferometry to determine the layer number of phosphorene, and confirm the results with reliable photoluminescence measurements. Furthermore, we successfully probed the dynamics of excitons and trions in monolayer phosphorene by controlling the photo-carrier injection in a relatively low excitation power range. Based on our measured optical gap and the previously measured electronic energy gap, we determined the exciton binding energy to be ~0.3 eV for the monolayer phosphorene on SiO2/Si substrate, which agrees well with theoretical predictions. A huge trion binding energy of ~100 meV was first observed in monolayer phosphorene, which is around five times higher than that in transition metal dichalcogenide (TMD) monolayer semiconductor, such as MoS2. The carrier lifetime of exciton emission in monolayer phosphorene was measured to be ~220 ps, which is comparable to those in other 2D TMD semiconductors. Our results open new avenues for exploring fundamental phenomena and novel optoelectronic applications using monolayer phosphorene., Comment: arXiv admin note: substantial text overlap with arXiv:1412.6701, arXiv:1411.6124

We retrospectively reviewed the accuracy of conventional transbronchial needle aspiration (cTBNA) in the subtyping of lesions located in or around central airways by comparing the histological diagnosis based on TBNA and surgical specimens.cTBNA was conducted in consecutive patients with lesions located in or around the central airways (trachea, left and right primary bronchi, hilar and mediastinal masses or lymph nodes) between October 2012 and May 2014 in Wuhan No. 1 Hospital. The aspirated specimens in all patients were performed cytological and/or histopathological examination. Of these patients, some were subjected to surgical resection and histopathological examination was performed by the Department of Pathology. In the patients with gross specimens, the final diagnosis was established based on histopathological results from these specimens.In 63 patients diagnosed with cTBNA for the lesions located in or around the central airways, 23 patients with a diagnosis of lung cancer or atypical hyperplasia underwent surgery. The final diagnosis based on histopathology of surgery specimen was lung cancer in 22 patients [3 small cell lung cancer (SCLC), 9 squamous cell carcinoma (SCC), 5 adenocarcinoma (ADC), 4 adenosquamous carcinoma (ADS) and 1 neuroendocrine carcinoma], and inflammatory pseudotumor in 1 patient. The overall diagnostic yield of cTBNA for lung cancer was 95.7% (22/23), but the accuracy for histological typing of lung cancer is only 63.6% (14/22), for adenosquamous lung carcinoma was only 25% (1/4).cTBNA is a safe and effective procedure that can be used for the diagnosis of central lung cancer. However, the accuracy of TBNA for the histological classification of lung cancer is relatively low, especially for adenosquamous lung carcinoma.

Monolayer phosphorene provides a unique two-dimensional (2D) platform to investigate the fundamental many-body interactions. However, owing to its high instability, unambiguous identification of monolayer phosphorene has been elusive. Consequently, many important fundamental properties, such as exciton dynamics, remain underexplored. We report a rapid, noninvasive, and highly accurate approach based on optical interferometry to determine the layer number of phosphorene, and confirm the results with reliable photoluminescence measurements. Based on the measured optical gap and the calculated electronic energy gap, we determined the exciton binding energy to be ~0.4 eV for the monolayer phosphorene on SiO2/Si substrate, which agrees well with theoretical predictions. Our results open new avenues for exploring fundamental phenomena and novel optoelectronic applications using monolayer phosphorene., arXiv admin note: substantial text overlap with arXiv:1411.6124, arXiv:1411.6200

The Cu3SbSe4 compound is an environmentally friendly and low-cost medium-temperature thermoelectric material, which is featured by its low thermal conductivity. The disadvantage of this compound lies in its intrinsic poor electrical transport property. In order to improve the electrical conductivity of Cu3SbSe4, in this work we are to increase its carrier concentration by one to two orders of magnitude though elemental doping. The sample composition of Cu2.95GaxSb1-xSe4 is designed to increase the hole carrier concentration by introducing Cu vacancies and substituting Ga3+ for Sb5+. The Cu2.95GaxSb1-xSe4 (x=0, 0.01, 0.02 and 0.04) samples are prepared by melting-quench method. The X-ray diffraction analysis indicates that the obtained samples are of single-phase with the tetragonal famatinite structure, and the energy-dispersive X-ray spectroscopy results show that the actual compositions of the samples are very close to their nominal compositions. The effect of Ga doping on the thermoelectric performance of Cu3SbSe4 compound is investigated systematically by electrical and thermal transport property measurements. According to our experimental results, the hole concentration of the sample is efficiently increased by substituting Sb with a small amount of Ga (x=0.01), which can not only substantially improve the electrical conductivity but also suppress the intrinsic excitation of the sample. The maximum power factor reaches 10 μW/cm·K2 at 625 K for the Ga doped sample with x=0.01, which is nearly twice as much as that of the sample free of Ga. Although the carrier concentration further increases with increasing Ga content, the hole mobility decreases dramatically with the Ga content increasing due to the increased hole effective mass and point defect scattering. Thus, the electrical transport properties of the samples deteriorate at higher Ga content, and the maximum power factors for the samples with x=0.02 and 0.04 reach 9 and 8 μW/cm·K2 at 625 K, respectively. The lattice thermal conductivities of the samples basically comply with the T-1 relationship, suggesting the phonon U-process is the dominant scattering mechanism in our samples. For the samples with x=0 and 0.01, the lattice thermal conductivities at high temperature deviate slightly from the T-1 curve due to the presence of intrinsic excitation. However, these deviations are eliminated for the samples with x=0.02 and 0.04 because the bipolar effect is effectively suppressed with the increasing of Ga content. Thus, Ga doping can reduce the bipolar thermal conductivity at high temperature by increasing the hole carrier concentration. Furthermore, the point defects introduced by Ga doping can also enhance the scattering of high-frequency phonons, leading to slightly reduced lattice thermal conductivities of Ga-doped samples at higher temperature. Finally, a maximum ZT value of 0.53 at 664 K is achieved in Ga-doped sample, which is 50% higher than that of the sample free of Ga.

Background The association between β2-adrenergic receptor (ADRB2) -16Arg/Gly polymorphism (rs1042713) and chronic obstructive pulmonary disease (COPD) risk has been investigated in many published studies. However, the results were inconclusive. A meta-analysis was performed to make a more precise estimation of the relationship. Methods The PubMed, EMBASE, ISI web of science, the Cochrane Database of Systematic Reviews, and Chinese databases (CNKI, Wanfang Data, CBM, VIP) were searched for published literature. Odds ratios (OR) with 95% confidence interval (CI) were used to assess the strength of association. Results Eleven studies, comprising 1,128 COPD patients and 1,182 controls, were included in the meta-analysis. Overall, there was no significant association between the ADRB2-16Arg/Gly polymorphism and COPD risk in general population. In the stratification analysis by potential confounding variables, significant associations were observed between the ADRB2-16Arg/Gly polymorphism and COPD risk among smoking Asians under the dominant genetic model and allele model (Arg vs. Gly) (dominant model: OR = 1.45, 95% CI = 1.04–2.01, P = 0.311 for heterogeneity, z = 2.22, P = 0.026 for OR; allele model: OR = 1.27, 95% CI = 1.03–1.57, P = 0.209 for heterogeneity, z = 2.20, P = 0.028 for OR), but not in other subgroups. Conclusion This meta-analysis suggested that the ADRB2-16Arg/Gly polymorphism might be a potential risk factor for the development of COPD in smoking Asian populations, but not in European descendents, and tobacco smoking probably increased the genetic susceptibility. More studies with larger sample sizes are needed to validate the results.

Background : In 2008 Wuhan University Medical School in China proposed to reform its curriculum by adapting the curriculum of the University of Chicago Medical School. Description : An assessment of Wuhan University Medical School's traditional curriculum conducted in 2009 informed the reform directions, which included course integration, use of clinical cases, improved relevance of basic sciences to clinical medicine, reduction of lecture time, increase in group and independent learning, and the use of formative assessments. Fifty student volunteers per year were chosen to participate in the reform, and the rest remained in the traditional curriculum. Evaluation : A student survey was conducted in 2011 to evaluate the reform by comparing the attitudes of those in the reform and standard curricula. Conclusions : The reform met the needs of the school, was generally well received, improved satisfaction in reform participants, and had a positive impact on students. Areas needing improvement were also identi...

To investigate the number of peripheral blood CD5(+) B cells and their ability of secreting IL-10 in patients with immune thrombocytopenia (ITP).Peripheral blood lymphocytes were isolated from 57 pre-treated, 40 post-treated ITP patients and 25 controls using Ficoll-Hypaque density centrifugation and then stained with PE-CD5/FITC-CD19 for flow cytometric analysis. After 24-hour culture, lymphocytes were stained with APC-IL-10 for intracellular cytokine detection. ELISA assay was employed to determine IL-10 concentration in supernatants.The percentage and absolute number of CD5(+) B cells in peripheral blood from pre-treated ITP patients were significantly higher than that from normal controls (3.75 ± 2.37)% vs (2.10 ± 1.08)%, P0.01; (6.29 ± 5.77)× 10(7)/L vs (3.06 ± 1.90)× 10(7)/L, P0.01. CD5(+) B cells expressed more intracellular IL-10 than other lymphocyte subsets both in ITP patients and normal controls. The percentages of IL-10(+) cells within CD5(+) B cells in pre-treated ITP patients and normal controls were (29.51 ± 20.73)% and(15.90 ± 9.58)%, respectively(P0.01). Intracellular mean fluorescence intensity (MFI) of IL-10 in CD5(+) B cells was 27.95 ± 13.99 in pre-treated patients, which was significantly higher than that in controls (P0.01). In contrast, IL-10 concentration in supernatants was (173.05 ± 102.50) ng/L in pre-treated ITP group, which was lower than that (230.61 ± 76.96) ng/L in controls. In patients who achieved remission, the number of CD5(+) B cells decreased to level comparable to normal controls. While intracellular IL-10 MFI of CD5(+) B cells in post-treated ITP patients remained as high as in pre-treated ones, the IL-10 concentration in supernatants increased to level similar to controls.The significantly increased number of CD5(+) B cells and accumulated IL-10 in CD5(+) B cells suggested impaired IL-10 secretion in ITP patients. The number and the ability of secreting IL-10 of CD5(+) B cells could be restored after effective treatments in patients with ITP.

The paper empirically explores how more trade transparency affects market liquidity. The analysis takes advantage of a unique setting in which the Shanghai Stock Exchange offered more trade transparency to market participants subscribing to a new software package. First, the results show that the additional data disclosure increased trading activity, but also increased transactions costs through wider bid-ask spreads. Thus, in contrast to popular policy belief, the paper finds that more transparency need not improve market liquidity. Second, the paper finds a particularly strong immediate liquidity impact accompanied by altered trading behavior, which suggests a significant impact on institutional traders subscribing relatively early. Lastly, since the effective level of market transparency is bound to depend on how many traders are subscribing to the data, the study can empirically establish the functional form between market-wide transparency and liquidity. The relationship is non-monotonic, which can explain the lack of consensus in the existing literature where each empirical study is naturally confined to specific parts of the transparency domain.

Starting from a CNNIC report and a survey investigation, the article shows the importance of promoting e-learning for college students and its potentiality. As E-learning has developed with new ideas such as equal Learning, the article further analyzes the psychological characteristics of college students and their influence on the current e-learning promotion. The argument has put forward s social psychological perspective on the study of e-learning development in universities.