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The electric field induced by the substrate could adjust the Schottky barrier from a p-type contact (WSe2/Gr) to an n-type contact (Gr/WSe2). Thus, it is more beneficial for the photo-thermionic electrons to transfer from graphene to WSe2 in Gr/WSe2.

Efficient interfacial light-electric interconversion in van der Waals (vdW) heterostructures is crucial for their optoelectronic applications. However, an in-depth understanding of the necessary process for device operation, namely interfacial charge transfer (CT), has thus far remained elusive. In this study, by using photon energy-dependent transient THz spectroscopy, we complementarily investigate the interfacial CT process in heterostructures comprising monolayers of WSe

Purpose: To construct deep learning (DL) models based on multicentre biparametric MRI (bpMRI) for the diagnosis of clinically significant prostate cancer (csPCa), and compare the performance of these models with that of Prostate Imaging Reporting and Data System (PI-RADS) assessment of expert-level radiologists based on multiparametric MRI (mpMRI).Methods: This study included 1861 consecutive men with mpMRI from seven hospitals, who underwent radical prostatectomy or biopsy. These patients were divided into training cohort (3 hospitals, 1216 patients) and external validation cohorts (4 hospitals, 645 patients). PI-RADS assessment was performed by expert-level radiologists. The DL models were constructed for the classifications between benign and malignant lesions (DL-BM), and between csPCa and non-csPCa (DL-CS). The integrated model combining a DL-CS model and PI-RADS (PIDL-CS) was constructed. The performance of the deep learning models and PIDL-CS were compared with those of PI-RADS.Results: In each external validation cohort, the area under receiver operating characteristic curve (AUC) values of DL-BM and DL-CS models were not significantly different from that of PI-RADS (Ps > 0.05), whereas the AUC of PIDL-CS was superior to that of PI-RADS (Ps < 0.05) except one external validation cohort (P > 0.05). The specificity of the PIDL-CS for the detection of csPCa was much more than that of PI-RADS (Ps < 0.05).Conclusion: Our proposed DL model can be a potential non-invasive auxiliary tool to predict csPCa. Further, PIDL-CS greatly increased the specificity in the detection of csPCa compared with PI-RADS assessment of expert-level radiologists, greatly reducing the unnecessary biopsies and helping radiologists achieve a precise diagnosis of csPCa.

Purpose This study aimed to develop deep learning (DL) models based on multicentre biparametric magnetic resonance imaging (bpMRI) for the diagnosis of clinically significant prostate cancer (csPCa) and compare the performance of these models with that of the Prostate Imaging and Reporting and Data System (PI-RADS) assessment by expert radiologists based on multiparametric MRI (mpMRI). Methods We included 1861 consecutive male patients who underwent radical prostatectomy or biopsy at seven hospitals with mpMRI. These patients were divided into the training (1216 patients in three hospitals) and external validation cohorts (645 patients in four hospitals). PI-RADS assessment was performed by expert radiologists. We developed DL models for the classification between benign and malignant lesions (DL-BM) and that between csPCa and non-csPCa (DL-CS). An integrated model combining PI-RADS and the DL-CS model, abbreviated as PIDL-CS, was developed. The performances of the DL models and PIDL-CS were compared with that of PI-RADS. Results In each external validation cohort, the area under the receiver operating characteristic curve (AUC) values of the DL-BM and DL-CS models were not significantly different from that of PI-RADS (P > 0.05), whereas the AUC of PIDL-CS was superior to that of PI-RADS (P P > 0.05). The specificity of PIDL-CS for the detection of csPCa was much higher than that of PI-RADS (P Conclusion Our proposed DL models can be a potential non-invasive auxiliary tool for predicting csPCa. Furthermore, PIDL-CS greatly increased the specificity of csPCa detection compared with PI-RADS assessment by expert radiologists, greatly reducing unnecessary biopsies and helping radiologists achieve a precise diagnosis of csPCa.

Graphene and its derivatives, due to their two-dimensional carbon nanostructures, have provided new opportunities to fortify organic dye-based photovoltaic and photocatalytic assemblies. In this article, we employed organic dyes Rhodamine B (RdB) and graphene oxide (GO) [or reduced graphene oxide (RGO)] to assemble the composite materials RdB–GO and RdB–RGO. It was found that both GO and RGO could strongly quench the fluorescence (FL) intensity of RdB. The mechanisms of FL quenching in both RdB–GO and RdB–RGO have been investigated by using femtosecond fluorescence up-conversion and transient absorption spectroscopy. When RdB was anchored on the GO (or RGO) surface, the solvent relaxation component 3.1 ps of pure RdB disappeared; instead, the ultrafast excited state electron transfer process (1–2ps) in RdB-GO and RdB-RGO was found and originated from the LUMO of RdB to the conduction band of GO (or RGO). We further reveal that the energy level change caused by GO reduction makes the energy levels of RGO closer to those of RdB, resulting in the electron transfer being more effective in RdB–RGO. Therefore, the RdB–RGO composite materials may have higher application values for dye-sensitized solar cells.

It was another difficult year for China in 2019. The Chinese economy and government revenue registered the lowest growth in nearly three decades. The employment situation has worsened and inflation driven by the surge in pork prices has reached its peak since 2012. Spending huge amounts of government money on social programmes has been China’s core coping strategy. This approach is however facing difficulties in localities with a smaller and less diverse revenue base. Social challenges will become even more manifest in 2020.

The United States’ fear of losing its technological edge to China is on the rise. The Trump administration has viewed China’s techno-industrial plans and policies as a national security threat. Recognising the reality that it cannot afford to have a Cold War or “cold peace” with the United States, China has shown willingness to make concessions, but only to a certain degree. The Trump administration’s growing hostility is unlikely to stop China from pursuing frontier technologies, which are a source of national competitiveness, security and pride for China as much as for the United States.

China had a bumpy year in 2018. The central government had to make a midyear adjustment with renewed emphasis on stabilising the economy and society prompted largely by the US-China trade war and a slew of domestic factors, such as the grieving middle class increasingly burdened by high living costs and growing household debts. By all signs, the year 2019 will be more difficult and a serious test is forthcoming for the Xi leadership.

China's quest to have world-class universities has entered a new phase since 2015, with the 'Double World-Class Project' replacing the '985 Project' and the '211 Project' launched in the 1990s. The transition from World-Class 1.0 to World-Class 2.0 provides a good window onto changes in China's policymaking. The prevailing literature has identifi ed broad trends such as institutionalization, decentralization and expanded participation. While this paper fi nds evidence in support of the prevailing literature, it also challenges the thesis of institutionalization, decentralization and expanded participation. The celebrated evolution from 'hierarchical governance' to 'network governance' or from 'consultation' to 'deliberation' in China's policymaking, however desirable, is premature—especially for multibillion, high-stakes policy initiatives such as the 'Double World-Class Project'.

After decades of large-scale rural-to-urban migration, a massive wave of return migration has emerged in China, signalling China’s entry to a new stage of economic and social development. Behind the new trend are the economic take-off of China’s hinterland and the ageing of the first-generation migrant workers. While potentially a benign transformative force for rural China, return migration also risks becoming a way to “dump” ageing, unproductive or laid-off migrant workers in the vast countryside.

In September 2017, China released a list of universities to be developed into world-class universities or universities with world-class disciplines. As Xi Jinping’s most important initiative in higher education, the “Double World-Class” project is expected to advance Chinese universities in major international league tables. While the best Chinese universities aspire to equal the world’s best, deeper changes are needed in the governing of universities, allocating of research funding and fostering of conducive research environment.

Gamma-ray bursts (GRBs) at high redshifts are expected to be gravitationally lensed by objects of different mass scales. Besides a single recent claim, no lensed GRB has been detected so far by using the gamma-ray data only. In this paper, we suggest that the multi-band afterglow data might be an efficient way to search for lensed GRB events. Using the standard afterglow model we calculate the characteristics of the lensed afterglow lightcurves under the assumption of two popular analytic lens models: point mass and Singular Isothermal Sphere (SIS) model. In particular, when different lensed images cannot be resolved, their signals would be superimposed together with a given time delay. In this case, the X-ray afterglows are likely to contain several X-ray flares of similar width in linear scale and similar spectrum, and the optical afterglow lightcurve will show rebrightening signatures. Since the lightcurves from the image arriving later would be compressed and deformed in the logarithmic time scale, the larger time delay (i.e. the larger mass of the lens), the easier is to identify the lensing effect. We analyzed the archival data of optical afterglows and found one potential candidate of the lensed GRB (130831A) with time delay $\sim$500 s, however, observations of this event in gamma-ray and X-ray band seem not to support the lensing hypothesis. In the future, with the cooperation of the all-sky monitoring gamma-ray detectors and multi-band sky survey projects, our method proposed in this paper would be more efficient in searching for strongly lensed GRBs., Comment: Accepted for publication in ApJ

Social policy scholars often take the view that welfare states can be classified into different types based on distinct political philosophies and stable institutional features. It is a challenge to position China in any such taxonomy, however. Using the volatile growth of educational expenditure in recent years as an example, this chapter suggests that China’s social policy in general, and educational policy in particular, has not evolved into a stable model. The tension between centralized mandates and decentralized financing generates greater irregularity than any existing theory can sufficiently explain. China often relies on top-down mobilization to achieve unfunded or underfunded policy mandates. Mobilization, however, cannot last long as it stresses and strains local governments. The alternation between mobilization and post-mobilization is highly disruptive for China’s welfare state building. Much more needs to be done to replace mobilization with a more regularized, sustainable, and equitable financing mechanism for education and other social programs.

China performed well in 2017 creating jobs, controlling inflation and promoting income growth. The Chinese Communist Party (CCP) had not been troubled by major disturbing incidents as in previous years. The single most important event in 2017 was the CCP’s 19th National Congress where “people’s ever-growing need for a better life versus unbalanced and inadequate development” was given emphasis. Addressing unbalanced development will likely be the CCP’s central task in the coming years.

The tension between mobilizing resources to meet education-related growth targets and regularizing educational funding for a more stable and sustainable growth is structurally rooted in China’s educational system, which features growth-oriented, centralized mandates and county-based, decentralized financing. It was manifested in 2012, when China experienced a ‘great leap’ in educational expenditure. Based on interviews and school-level data from a province in western China, this article suggests that the ‘great leap’ was real rather than fabricated. Local governments have demonstrated remarkable capacity in resource mobilization involving both formal and informal strategies. It also shows the scarring effects of too much mobilization. The ‘great leap’ has clearly stressed and strained local governments to the extent that there is clear evidence of policy non-compliance and greater irregularity in government funding for education in the aftermath.

Mutations in the potassium channel genes may be linked to the development of epilepsy and affect the blood potassium levels. Therefore, accurate determination of potassium in the blood will be critical to diagnose the cause of epilepsy. CE is a competent technique for the fast detection of multiple ions, but complicated matrices of a blood sample may cause significant variation of migration times and the peak shape. In this work, a procedure for rapid stabilization of the capillary inner surface through preflushing of a blood sample was employed. The process takes only 40 min for a capillary and then it can be used for more than 2 weeks. No pretreatment of the blood sample or other surface modification of the capillary is needed for the analysis. The RSDs of the migration time and peak area were reduced to 1.5 and 5.1% from 12.6 and 14.5%, respectively. The proposed method has been successfully applied to the determination of the potassium contents in the blood sample of patients with epilepsy at different stages. The recoveries of potassium ions in these blood samples are in a range from 86.5 to 104.5%.

Efficient interfacial light-electric interconversion in van der Waals heterostructures is critical for their optoelectronic applications. Using time-resolved terahertz spectroscopy and transient absorption spectroscopy, the charge transfer and the dynamical interlayer excitons were investigated in the heterostructures comprising monolayer WSe

A porous silica gel plate impregnated with a colorimetric reagent, 4-amino-3-penten-2-one (Fluoral-P) has been fabricated for the first time to determinate formaldehyde. The reaction of formaldehyde and Fluoral-P produced a yellow product 3,5-diacetyl-1,4-dihydrolutidine (DDL), which was further photographed by a smartphone. A good linear relationship has been found between the intensity of blue component from the digital image and formaldehyde concentration in the range of 0–50 mg L−1 with low detection limit of 2.2 ± 0.1 mg L−1. A good precision in the range of 0.59–7.75%RSD and an accuracy with the relative error of +3.7% from control samples are also obtained. These results demonstrate that our developed low-cost sensor, together with digital image colorimetry, has potential for sensitively and quickly measuring formaldehyde.

A facile solution-phase synthesis of black γ-phase CsPbI3 nanowire clusters was developed using poly(methyl methacrylate) (PMMA) as surfactant. PMMA was found to efficiently retard the crystal growth, thereby inducing anisotropic growth for formation of the nanowire structure, while the intermolecular hydrogen bonds of PMMA act as a driving force for self-assembly of the nanowires.

The as-grown atomically thin transition metal dichalcogenides (TMDs) usually have extremely large surface-to-volume ratios. Hence, the electrical and optical properties are always affected by the adsorption of atmospheric gases. By using optical pump terahertz (THz) probe spectroscopy, THz photoconductivity dynamics of chemical vapor deposition grown monolayer MoS

China’s 13th Five-Year Plan (FYP) maps out China’s economic and social development in the next five years under the guidelines of “innovative development”, “coordinated development”, “green development”, “open development” and “shared development”. It features a pro-active approach to programmes that are “social investment” in nature and a conservative approach to programmes seen as “social consumptions”. As the economy slows down, the 13th FYP period is likely to see social expenditures proceeding at a slower pace.

The gravitational-wave detection by the LIGO-Virgo scientific collaboration shows that the black hole and neutron star (BH-NS) or BH-BH systems with a BH mass of tens of solar masses widely exist in the universe. Two main types of scenarios have been invoked for the formation of BH-NS/BH systems, including isolated binary evolution in galactic fields and dynamical interactions in dense environments. Here we propose that if the BH-NS/BH systems are formed from isolated binary evolution, the supernova (SN) signal associated with the second core collapse would show some identifiable features, due to the accretion feedback from the companion BH. Depending on the binary properties, we show that the SN lightcurve could present a sharp peak around $\sim10$ days, with luminosity even at the level of the super luminous SNe ( e.g. $\sim10^{44}~\rm erg~s^{-1}$) or present a plateau feature lasting for several tens of days with regular luminosity of core collapse SNe. Comparing the event rate density of these special SN signals with the event rate density of LIGO-Virgo detected BH-NS/BH systems could help to distinguish the BH-NS/BH formation channel., Comment: ApJL in press

We theorize the contested process of ideological imprinting. We argue that ideological imprinting tends to be both hierarchical and sequential, and whether organizational imprinters can effectively...

Evidence for the central engine of gamma-ray bursts (GRBs) has been collected in the Neil Gehrels \emph{Swift} data. For instance, some GRBs show an internal X-ray plateau followed by very steep decay, which is difficult to be interpreted within the framework of a black hole (BH) central engine, but are consistent within a rapidly spinning magnetar engine picture. The very steep decay at the end of the plateau suggests a sudden cessation of the central engine, which is explained as the collapse of a supra-massive magnetar into a black hole when it spins down. Here we propose that some additional evidence, such as a second X-ray plateau feature would show up, if the fall-back accretion could activate the newborn BH and sufficient energy could be transferred from the newborn BH to the GRB blast wave. With a systematic data analysis for all long GRBs, we find three candidates in \emph{Swift} sample, i.e., GRBs 070802, 090111, and 120213A, whose X-ray afterglow light curves contain two plateaus, with the first one being an internal plateau. We find that in a fairly loose and reasonable parameter space, the second X-ray plateau data for all 3 GRBs could be well interpreted with our proposed model. Future observations are likely to discover more similar events, which could offer more information of the properties of the magnetar as well as the newborn BH., accepted for publication by ApJ

Chinese society was largely stable in 2015 despite the slower economic growth and the stock market crash. Overall, the Chinese Communist Party (CCP) has prevented local protests from spreading and escalating into a political threat on a national scale. In November 2015, the CCP announced the guidelines for the 13th Five-Year Plan (2016-2020). The shift towards “innovative, coordinated, green, open and shared” development would require more changes in government and society.

Chongqing is the latest and largest municipality directly under the administration of the central government and the only one in China's vast inland regions. Sun Zhengcai, a new Politburo member at the 18th Party Congress, became Chongqing's party secretary in November 2011. The former minister of agriculture and later party secretary of Jilin, Sun has demonstrated a down-to-earth working style. Policy-wise, he continues but refines what Chongqing has been doing, with possible breakthroughs in some areas.

China has begun the full-fledged implementation of Xi's agenda of comprehensively deepening reform. Socially, the much anticipated urbanisation plan was announced in April 2014. Reforms in the social domain have made some progress, albeit uneven across issue areas. As China is in the transition to the economic and social “new normal”, it takes time, vision, will and skills to balance the multiple goals of stabilising growth, adjusting structure, improving livelihoods and deepening reform.