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• NaBa 4- x B 3 O 9 :x Eu3+ simultaneously generates intense emissions at both 617 and 706 nm. • The generation of emission at 706 nm due to Eu3+ ions occupy the [BaO8] sites. • NaBa 4- x B 3 O 9 :x Eu3+ phosphors may achieve multifunctional LED applications. Currently, most trivalent europium ion (Eu3+)-activated phosphors exhibit dominant red emissions at around 616 nm originating from 5D 0 → 7F 2 transition. However, recently, some works have indicated that Eu3+ ions could generate intense far-red emission (∼706 nm), which is assigned to the transition 5D 0 → 7F 4. Thus, utilization of the far-red emission from the transition 5D 0 → 7F 4 could expand the application fields of Eu3+-activated phosphors. Herein, we prepare a series of NaBa 4- x B 3 O 9 : x Eu3+ (x = 0.01, 0.05, 0.1, 0.15, and 0.2 mol) phosphors via the conventional solid-state reaction method. These phosphors possess dual intense emission at around 617 nm (5D 0 → 7F 2) and 706 nm (5D 0 → 7F 4) owing to Eu3+ ions occupying the distorted [BaO 8 ] sites with C 2 symmetry. Furthermore, owing to the dual emission, the NaBa 4 B 3 O 9 :Eu3+ phosphors could be used in various applications such as plant growth lighting or phosphor-converted white light emitting diodes. [ABSTRACT FROM AUTHOR]

There are very rich publications devoted to group sequential design, adaptive design and trial monitoring for continuous, binary and time to event endpoints. Many authors also discuss fixed design, blinded sample size re-estimation design and group sequential design for studies with a negative binomial outcome. Nonetheless, literature is sparse in adaptive design for a trial with a negative binomial endpoint. The features of such an endpoint in a flexible trial design setting remains inadequately understood. In this research, we seek to bridge this knowledge gap by offering a thorough examination of utilizing data components from a two-stage adaptive design for unblinded conditional power calculation and corresponding sample size re-estimation. We also provide expression for calculating the probability of meeting the futility criterion to determine the appropriate timing for the interim analysis. To evaluate the performance of the design, we conduct simulations to assess its operation characteristics. Finally, we provide a helpful and illustrative example to demonstrate the practical applications of the methods. [ABSTRACT FROM AUTHOR]

In gypsum–carbonate rock assemblages, multistage and complex fluids control the formation of dolomite reservoirs that are a focus of hydrocarbon exploration. It is difficult to determine the types of dolomite reservoirs and their formation mechanisms due to the diverse rock assemblages and multiple stages of diagenesis. In this study, we investigated the petrology, reservoir physical properties, and geochemistry of the 6th sub-member of member five of the Majiagou Formation (i.e. Ma56) in the Ordos Basin, China. These data were used to determine the nature and types of gypsum–carbonate rocks, and constrain their reservoir characteristics and diagenetic history, and fluid-related mechanisms that led to dolomite reservoir development and preservation. The Ma56 was deposited on a restricted evaporatic platform in the North China Craton, and contains three main types of dolomite reservoirs with variable types of reservoir space. Dolomite reservoir formation was closely related to penecontemporaneous dolomitization, karstification, and differential cementation. Early large-scale dolomitization produced dolomitized carbonate sediments that were resistant to compaction and dissolution, which was conducive to the preservation of primary and secondary pores. The intermittent exposure and dissolution of mound–shoal facies sediments, due to high-frequency sea-level fluctuations, was the dominant mechanism for formation of secondary dissolved pores and high-quality reservoirs. During burial, differential cementation occurred due to interaction between fluids and pore size, which determined the extent of reservoir preservation. In general, the studied dolomite reservoirs have undergone multistage diagenesis and alteration, which led to complex and multistage development of the reservoir porosity. However, the reservoir lithology and pore space developed mostly in the depositional to penecontemporaneous stages. Our results provide new insights into the origins of deeply buried dolomite reservoirs in carbonate–evaporite successions. [ABSTRACT FROM AUTHOR]

The self-regulation theory suggests that self-monitoring is a crucial factor in the progress of goal pursuit. Based on this theory, we explored the influence and mechanism of time management disposition and self-monitoring in relation to procrastination. In the study sample of 503 Chinese college students, we found that procrastination was negatively correlated with time management disposition and self-control, time management disposition was significantly and positively correlated with self-control, and self-monitoring was not significantly correlated with the other variables. Time management disposition was found to play a partially mediating role between self-control and procrastination, whereas indirect relationship between self-control and procrastination through time management disposition was moderated by self-monitoring, namely, self-monitoring moderated the effect of time management disposition on procrastination. The results of this study suggest that self-monitoring can strengthen or weaken the inhibition effect of self-control on procrastination thought time management disposition. [ABSTRACT FROM AUTHOR]

To recognize the modulation style adopted in multiple-input-multiple-output orthogonal space-time block code (MIMO-OSTBC) systems, a cooperative modulation recognition algorithm based on the one-dimensional convolutional neural network (1D-CNN) was proposed. With the lossless I/Q signal selected as shallow features, the zero-forcing blind equalization was first leveraged to improve the discrimination of different modulation signals. Then the 1D-CNN recognition model was devised and trained to extract deep features from shallow ones. Later, two decision fusion strategies of voting-based and confidence-based were leveraged in the multiple-antenna receiver to improve recognition accuracy. Experimental results show that the proposed algorithm can effectively recognize five modulation types {BPSK, 4PSK,8PSK,16QAM,4PAM}, with a 100% recognition accuracy when the signal-to-noise is equal or greater than -2 dB. [ABSTRACT FROM AUTHOR]

In this paper, the problem of exponential synchronisation between time-delay spatiotemporal network and target system is studied. Based on the Lyapunov stability principle, the Lyapunov–Krasovskii generic function with exponential form is designed, and the form of the synchronisation controller is determined, so that the exponential synchronisation is realised between the time-delay spatiotemporal network and the target system. In simulation, Fisher–Kolmogorov system is further selected as the network node to verify the rationality of synchronisation scheme. This technology fully considers the effect of time delay on network synchronisation performance, making the synchronisation scheme more practical. In addition, exponential synchronisation technology can effectively adjust the rate of network synchronisation. [ABSTRACT FROM AUTHOR]

Metal-free semiconductors with desirable characteristics have recently gained great attention in the field of hydrogen generation. The non-metal material B2S3 has two phases, hexagonal B2S3 (h-B2S3) and orthorhombic B2S3 (o-B2S3), which compose a novel class of 2D materials. Both h-B2S3 and o-B2S3 monolayers are direct semiconductors with bandgaps of 2.89 and 3.77 eV by the Heyd-Scuserria-Ernzerhof (HSE) function, respectively. Under appropriate uniaxial strain (1%), the bandgap of h-B2S3 can be decreased to 2.8 eV. The carrier mobility can reach 1160 cm2 V−1 s−1, supporting the fast migration of photo-induced carriers. Most importantly, the band edges of both h-B2S3 and o-B2S3 cover the reduction and oxidation levels for water splitting. We explore the process of photocatalytic water splitting on h-B2S3 monolayers by analyzing the feasibility of the decomposition of H2O and the generation of H2. The results indicate that the special mesoporous structure of B2S3 is helpful for photocatalytic hydrogen production. The new nanomaterial, B2S3, offers great promise as a metal-free photocatalyst due to its tunable bandgaps, its useful band edges, and its other excellent electronic properties. [ABSTRACT FROM AUTHOR]

Background: Non-invasive prenatal screening (NIPS) is widely used as the alternative choice for pregnant women at high-risk of fetal aneuploidy. However, whether NIPS has a good detective efficiency for pregnant women at advanced maternal age (AMA) has not been fully studied especially in Chinese women.Methods: Twenty-nine thousand three hundred forty-three pregnant women at AMA with singleton pregnancy who received NIPS and followed-up were recruited. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), receiver operating characteristic (ROC) curves and the Youden Index for detecting fetal chromosomal aneuploidies were analyzed. The relationship between maternal age and common fetal chromosomal aneuploidy was observed.Results: The sensitivity, specificity, PPV, NPV of NIPS for detecting fetal trisomy 21 were 99.11, 99.96, 90.98, and 100%, respectively. These same parameters for detecting fetal trisomy 18 were 100, 99.94, 67.92, and 100%, respectively. Finally, these parameters for detecting trisomy 13 were 100, 99.96, 27.78, and 100%, respectively. The prevalence of fetal trisomy 21 increased exponentially with maternal age. The high-risk percentage incidence rate of fetal trisomy 21 was significantly higher in the pregnant women at 37 years old or above than that in pregnant women at 35 to 37 years old. (Youden index = 37).Conclusion: It is indicated that NIPS is an effective prenatal screening method for pregnant women at AMA. [ABSTRACT FROM AUTHOR]

Large Schottky barrier at the electric contact interface drastically hinders the performance of two-dimensional (2D) semiconductor devices, because of which it is crucial to develop better methods to achieve the ohmic contact. Recently, a new field effect transistor (FET) device was constructed by the popular 2D channel material MoS2 and an electrode material borophene was detected theoretically, but the large Schottky barrier still existed. Hence, we used surface functional groups modification on the borophene surface to regulate this Schottky barrier, based on ab initio electronic structure calculations and quantum transport simulations. Our study shows that this method makes it possible to obtain tunable metal work functions in a wide range, and the ohmic contact can still be realized. Although van der Waals (vdW) contacts were observed at all the interfaces between the 2D borophene-based metals and the monolayer MoS2, the Fermi level pinning (FLP) effect was still obvious, and existed in our proposed system with the ohmic contact. Moreover, we also discuss the origin of the FLP with varying degrees. It was found that the interface dipole and metal-induced gap states (MIGS) would be responsible for the FLP of vertical and lateral directions, respectively. More precisely, we find that the size of MIGS is dependent on the relative orientation between the functional group and metal–MoS2 interface. This work not only suggests that surface functional group modification is effective in forming ohmic contact with MoS2, but also holds some implication in the fundamental research on metal–semiconductor contacts with the vdW type. [ABSTRACT FROM AUTHOR]