Search

The 2D semiconductors are an ideal platform for exploration of bosonic fluids composed of coupled photons and collective excitations of atoms or excitons, primarily due to large excitonic binding energies and strong light‐matter interaction. Based on first‐principles calculations, it is demonstrated that the phonon polaritons formed by two infrared‐active phonon modes in monolayer MoSi2N4 and WSi2N4 possess ultra‐high confinement factors of around ≈105 and 103, surpassing those of conventional polaritonic thin‐film materials by two orders of magnitude. It is observed that the first bright exciton possesses a substantial binding energies of 750 and 740 meV in these two monolayers, with the radiative recombination lifetimes as long as 25 and 188 ns, and the Rabi splitting of the formed cavity‐exciton polaritons reaching 373 and 321 meV, respectively. The effective masses of the cavity exciton polaritons are approximately 10−5me, providing the potential for high‐temperature quantum condensation. The ultra‐confined and ultra‐low‐loss phonon polaritons, as well as strongly‐coupled cavity exciton polaritons with ultra‐small polaritonic effective masses in these two monolayers, offering the flexible control of light at the nanoscale, probably leading to practical applications in nanophotonics, meta‐optics, and quantum materials. [ABSTRACT FROM AUTHOR]

The realization of high‐temperature exciton macroscopic quantum phases in materials still remains challenging due to strict constraints in thermal stabilities and excitonic lifetimes. In this work, by using first‐principles calculations, the exciton dispersions and macroscopic quantum phase transitions of 2D α‐ and β‐Te are investigated. The excitons with lowest eigen energy for both α‐ and β‐Te are dark restricted by the crystal‐field symmetries. The Bose–Einstein condensation (BEC) transition for α‐ and β‐Te can be realized at 165.4 and 32.8 K with low excitation power densities of 0.42 × 1012 and 1.0 × 1012 cm−2, respectively. Furthermore, the phase transitions from insulating free exciton (FE) gas to conducting electron–hole plasma (EHP) and electron–hole liquid (EHL), as well as that from BEC to superfluidity phases are also predicted. Finally, the authors investigate the microscopic dynamics for bright excitons of 2D tellurium and find that they reach thermal equilibrium at 1–50 fs and excitonic lifetimes can reach 1–40 ns, beneficial for experimental observation of quantum condensate states. The findings in this work not only demonstrate the excellent optoelectronic properties of 2D tellurium allotropes, but also provide a promising platform for experimental realization of high‐temperature excitonic macroscopic quantum condensates. [ABSTRACT FROM AUTHOR]

Understanding the full electron–phonon and phonon–phonon interaction effects in semiconductors is crucial for tuning electronic and phonon transport properties with the purpose to the enhancement of thermoelectric performances. In this work, based on the detailed investigations on 2D lead phosphorene (PbP) by using the first‐principle calculations, it is demonstrated that, in α−$\alpha -$, β−$\beta -$, and γ−$\gamma -$PbP, the electron–phonon interactions are significantly stronger than conventional group‐IV monolayers such as silicene by five orders in magnitude, and intravalley scatterings dominate over the intervalley scattering due to less degenerate band extrema near Fermi level. Based on the selection‐rule analysis, it is found that the symmetry breaking in the janus γ phase compared to the higher‐symmetry α phase allows fewer symmetry operations, leading to more allowed scattering channels for electrons and phonons, subsequently suppressing the electron and phonon transport in γ−$\gamma -$PbP. Due to the low Debye temperatures, and strong four‐phonon interactions, the lattice thermal conductivities at room temperature in these monolayers are sharply decreased. Finally, it is found that the maximum thermoelectric figure of merits for these three monolayers reach 0.90/0.24/1.25 at room temperature, respectively. This work not only paves the way for the promising applications of PbP monolayers in thermoelectric devices, but also suggests that symmetry breaking and strong high‐order phonon–phonon interactions are crucial to identifying excellent thermoelectric materials. [ABSTRACT FROM AUTHOR]

Early adverse life events (EALs) increase susceptibility to depression and impair cognitive performance, but the physiological mechanisms are still unclear. The target of this article is to clarify the impact of adverse childhood experiences on emotional and cognitive performance from the perspective of the heart–brain axis. We used the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) to test cognitive function and the Childhood Trauma Questionnaire (CTQ) to assess adverse childhood experiences. Heart rate variability (HRV) and electroencephalograms (EEG) were acquired at rest. We observed that subjects with depression had experienced more traumatic events during their childhood. Furthermore, they exhibited lower heart rate variability and higher power in the delta, theta, and alpha frequency bands. Moreover, heart rate variability partially mediated the association between childhood trauma exposure and depressive symptoms. Our findings suggested that adverse life events in childhood could influence the development of depression in adulthood, which might be linked to cardiac autonomic dysfunction and altered brain function. [ABSTRACT FROM AUTHOR]

Meat is the main source of protein nutrition for humans. However, given the increasing population and environmental pressure, a shortage of meat is expected in the future. The preparation of plant‐based (meat) products using existing processing methods represents a breakthrough to solve the shortage of traditional animal meat in the future, and texture is a key issue determining whether plant‐based (meat) products can replace traditional animal meat. Therefore, this review highlights recent progress in the texture of plant‐based (meat) products. First, the texture changes in plant‐based (meat) products were reviewed based on components (proteins, starch, lipids, food additives) and processing methods (processing factors, instrumental factors). Then, the current methods used to analyze the texture of plant‐based (meat) products were summarized based on sensory evaluation and instrumental analysis (mechanical analysis, spectral analysis, and image analysis). Finally, this review outlined methods to improve the texture quality of plant‐based (meat) products and analytical evaluation methods and provided an outlook on future research priorities. [ABSTRACT FROM AUTHOR]

Catalytic efficiency is crucial to a reaction system and is intrinsically related to the physical and chemical conditions. One of the challenges to enhance the catalytic efficiency has been the limited activity of metal catalysts for their state transformation. Usually, metal centers in homogeneous systems show better catalytic activity than their heterogeneous counterparts but lower stability due to the thermodynamic instability. Combining the features of both systems, herein, we report the "homogenization of heterogeneous catalysis" to illustrate the state transformation of Pd(II)x-UiO-67-bpy, which exhibits good catalytic properties and stability in the cyclization of isonitriles with N-acyl-o-alkynylanilines. The regulation of UiO-67-bpy on palladium active species at different stages of the reaction time realizes the efficient utilization of the Pd catalyst with high TONs (turnover numbers) and further decreases the loadings of metal species and alkali. This state transformation of the catalyst not only endows the Pd(II) species with high catalytic activity and stability, but also offers new insights into the catalytic behavior of heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Nitrile represents a synthetically important class of compounds, relevant to the preparation of fine organic chemicals, natural products, and biologically active molecules. The electronegative nitrogen atom and electropositive carbon atom of cyano group endow nitriles with rich and diverse chemical properties. Traditional chemical transformations of nitriles usually involve the use of strong acids, bases, and other harsh conditions. To overcome these limitations, various catalytic methods have been explored both in homogeneous and heterogeneous systems. In this review, we summarize some of the recent progress on the development of efficient synthetic methods involving nitriles. Especially, the classic transformations of nitriles including hydration, hydrolysis and reduction reactions are discussed in detail, which provide rapid access to a series of important small molecules, such as amides, ketones, amines, and imines. The reaction development, as well as the design of the catalytic system will be discussed with special emphasis placed on the mechanistic aspects. [ABSTRACT FROM AUTHOR]

Appearance and processing characteristics of 45 japonica rice samples, collected from different regions in Jiangsu province, were investigated and evaluated in this study. Specifically, the chalkiness degree had been presented significant differences among different cultivars and regions. The average chalkiness degree varied from 6.81% to 15.34% for different regions and from 1.93% to 28.31% for different cultivars. The minimum head rice rate of cultivars from four regions, NJ9108 (HA), was 80.5%. The AC of CNG10, HD5, and PJ surpassed 13.68% and lower than 11.33% for the others. The protein content ranged from 6.1% to 11%, and the taste value was significantly different among cultivars. In addition, the RVA curves of the samples were similar, but the peak viscosities of NG8 and NJ5055 were higher than others, and there were significant differences in RVA traits among regions. Cultivars were the main reasons for the difference in appearance and processing quality of japonica rice, while environmental factors had leaded to the change of rice composition, texture, and gelatinization. [ABSTRACT FROM AUTHOR]

Molecular dynamics (MD) simulations are employed to study the coalescence behaviors of nano-droplets on the stripy substrates decorated with spaced graphene nanoribbons (GNRs) for the first time. Results show that the stripe-induced restriction effect causes great inhibition to the coalescence dynamics, in which the downward movement of the droplet resulting from the penetration of atoms plays a predominant role. And the larger the intervals are, the heavier the restriction effect becomes. Additionally, it is found that the diffusion direction of the droplet during the coalescence process can be altered under different width of the stripe. Furthermore, when the direction of stripes is placed in accordance with that of the coalescence, the coalescence process would be faster. More importantly, based on our studies, the stripy surfaces with gradient intervals are well designed, where the coalescence behaviors could be finely manipulated. This work may open up a new way to control the coalescence dynamics by designing the stripy surface, which can provide guidance for some potential applications, such as micro-coating, micro-fabricated devices and even 3D printing. Coalescence dynamics of nano-droplets is greatly affected by the heterogeneous stripy surfaces and can be effectively manipulated by tuning the configuration of the stripy substrate. Unlabelled Image • Coalescence dynamics of droplets on heterogeneous stripy surfaces is investigated. • The effect of stripy substrates is thoroughly and detailed revealed from an atomistic view. • The interval distance, the width of stripes and the arrangement mode of stripes are considered. • Coalescence behaviors could be finely controlled by the well-designed stripy surfaces with gradient intervals. [ABSTRACT FROM AUTHOR]

Abstract Electron transport properties of optimized typical Si m C n /C n clusters, including Si 4 C, Si 8 C 5 , Si 9 C 6 , C 6 , C 12 and C 13 , connected to zigzag graphene nanoribbon (ZGNR) electrodes are theoretically studied through first-principles density functional theory (DFT). As for Si 4 C, Si 8 C 5 , Si 9 C 6 clusters, the transmission values at the fermi level show a decreasing tendency with the increase in the number of carbon and silicon atoms. Interestingly, Si 9 C 6 cluster with ring structure (C 6) has poor electron transport properties in spite of C 6 showing good electron transport properties. Although C 12 cluster shows smaller transmission values at the fermi level, when adding an atom to it, - C 13 shows excellent electron transport properties. The electrode coupling of ZGNR-C 12 is the strongest compared with ZGNR-C 6 and ZGNR-C 13 because it forms sp3 orbital which has stronger bond. Our findings may pave a new path for the exploration of nano electronics. [ABSTRACT FROM AUTHOR]

To investigate the changes in sleep quality, heart rate variability (HRV) and resting-state electroencephalogram (rsEEG) in patients with major depressive disorder (MDD), and to explore whether HRV and rsEEG may be served as more convenient tools to assess sleep quality in MDD patients. We included a total of 91 subjects (46 healthy controls and 45 MDD patients) and compared their sleep quality, HRV and power spectra of rsEEG. Correlation analyses were conducted to discuss the relationship between HRV and seven factors of PSQI. Multiple linear regression model was used to examine whether absolute band power could predict sleep quality in MDD patients. We found higher PSQI scores and lower levels of HRV in depressive individuals compared with healthy controls. In MDD patients, sleep latency was negatively correlated with RMSSD and HF. Delta, theta, and alpha band power of rsEEG were higher in MDD patients. Regression analyses showed delta band power of TP8, as well as theta, alpha band power of AF3 predicts PSQI score of MDD patients. The findings of our study show that some aspects of sleep problems had negative correlations with parasympathetic activity and the regression model supports that the band power of rsEEG may be used as a potential indicator to evaluate the sleep quality in MDD patients. Cortical hyperarousal may be one of the reasons leading to poor sleep quality of MDD patients. And resting-state EEG can be used as a potential indicator for clinical assessment of MDD patients' sleep quality. • Autonomic imbalance and sleep disturbance are common issues in MDD patients. • Absolute band power of resting-state EEG is higher in MDD patients. • MDD patients' cortical hyperarousal may lead to their poor sleep quality. • Resting-state EEG predicts sleep quality of MDD patients. [ABSTRACT FROM AUTHOR]

Drug delivery methods can impact efficacy as much as the nature of the drug itself. Microparticles made of biodegradable polymers such as poly(D, l -lactide- co -glycolide) and poly(lactic acid) (PLA) have been studied extensively for controlled release of diverse drugs. By using a modified solvent extraction/evaporation method called precision particle fabrication (PPF), uniform microparticles such as single-wall microspheres, double-wall microspheres and liquid-core microcapsules have been fabricated with precise control of their geometric structures. By producing particles of uniform size, which has crucial impact on drug release behaviors, PPF-fabricated microparticles provide unique insights about drug release mechanism. Using small-molecule and macromolecule model drugs, our group demonstrated that physicochemical properties of the polymers and drugs and structural properties of the matrix can greatly impact drug distribution within microparticles, particle erosion and drug release rates. By careful selection of particle size and shell thickness, uniform microparticles can achieve “zero-order”, pulsatile or tandem release of drugs. [ABSTRACT FROM AUTHOR]

Purpose: Pulsatile delivery of proteins, in which release occurs over a short time after a period of little or no release, is desirable for many applications. This paper investigates the effect of biodegradable polymer shell thickness on pulsatile protein release from biodegradable polymer microcapsules. Methods: Using precision particle fabrication (PPF) technology, monodisperse microcapsules were fabricated encapsulating bovine serum albumin (BSA) in a liquid core surrounded by a drug-free poly(lactide- co-glycolide) (PLG) shell of uniform, controlled thickness from 14 to 19 μm. Results: When using high molecular weight PLG (Mw 88 kDa), microparticles exhibited the desired core-shell structure with high BSA loading and encapsulation efficiency (55-65%). These particles exhibited very slow release of BSA for several weeks followed by rapid release of 80-90% of the encapsulated BSA within 7 days. Importantly, with increasing shell thickness the starting time of the pulsatile release could be controlled from 25 to 35 days. Conclusions: Biodegradable polymer microcapsules with precisely controlled shell thickness provide pulsatile release with enhanced control of release profiles. [ABSTRACT FROM AUTHOR]

Abstract: Biodegradable polymer microparticles are promising delivery depots for protein therapeutics due to their relatively simple fabrication and facile administration. Double-wall microspheres (DWMS) comprising a core and shell made of two distinct polymers may provide enhanced control of the drug release profiles. Using precision particle fabrication (PPF) technology, monodisperse DWMS were fabricated with model protein bovine serum albumin (BSA)-loaded poly(lactide-co-glycolide) (PLG) core and drug-free poly(d,l-lactic acid) (PDLL) shell of uniform thickness. Monolithic single-wall microspheres were also fabricated to mimic the BSA-loaded PLG core. Using ethyl acetate and dichloromethane as shell- and core-phase solvents, respectively, BSA was encapsulated selectively in the core region within DWMS with higher loading and encapsulation efficiency compared to using dichloromethane as core and shell solvents. BSA in vitro release rates were retarded by the presence of the drug-free PDLL shell. Moreover, increasing PDLL shell thickness resulted in decreasing BSA release rate. With a 14-μm thick PDLL shell, an extended period of constant-rate release was achieved. [Copyright &y& Elsevier]

Biodegradable polymer double-wall microspheres (DWMS) are promising vehicles for macromolecular therapeutics such as proteins and peptides. Using precision particle fabrication (PPF) technology, uniform DWMS with outer diameter approximately 55 μm were fabricated comprising poly(lactide- co-glycolide) cores encapsulating bovine serum albumin (BSA) and approximately 10 μm thick, drug-free, poly(lactic acid) (PLA) shells of varying PLA molecular weight. Also, monolithic single-wall microspheres (SWMS) were fabricated to mimic the BSA-loaded core. The use of relatively fast-extracting ethyl acetate and slowly extracting dichloromethane as shell- and core-phase solvents, respectively, was found to produce DWMS with well-defined core-shell structure, high BSA encapsulation efficiency, and the desired localization of protein in the particle core. Initial protein distribution, particle erosion, and in vitro protein release from DWMS and SWMS were examined. The presence of a BSA-free shell in DWMS decreased the protein release rate and extended the duration of release from approximately 50 days to 70-80 days, demonstrating the capacity of such DWMS to provide enhanced control of protein delivery rates. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 102:1601-1609, 2013 [ABSTRACT FROM AUTHOR]

Abstract: We have designed and evaluated a dual anticancer delivery system to provide combined gene therapy and chemotherapy. Double-walled microspheres consisting of a poly(d,l-lactic-co-glycolic acid) (PLGA) core surrounded by a poly(lactic acid) (PLA) shell were fabricated via the precision particle fabrication (PPF) technique. We make use of the advantages of double-walled microspheres to deliver chitosan–DNA nanoparticles containing the gene encoding the p53 tumor suppressor protein (chi-p53) and/or doxorubicin (Dox), loaded in the shell and core phases, respectively. Different molecular weights of PLA were used to form the shell layer for each formulation. The microspheres were monodisperse with a mean diameter of 65 to 75μm and uniform shell thickness of 8 to 17μm. Blank and Dox-loaded microspheres typically exhibited a smooth surface with relatively few small pores, while chi-microspheres containing p53 nanoparticles, with and without Dox, presented rough and porous surfaces. The encapsulation efficiency of Dox was significantly higher when it was encapsulated alone compared to co-encapsulation with chi-p53 nanoparticles. The encapsulation efficiency of chi-p53 nanoparticles, on the other hand, was not affected by the presence of Dox. As desired, chi-p53 nanoparticles were released first, followed by simultaneous release of chi-p53 nanoparticles and Dox at a near zero-order rate. Thus, we have demonstrated that the PPF method is capable of producing double-walled microspheres and encapsulating dual agents for combined modality treatment, such as gene therapy and chemotherapy. [Copyright &y& Elsevier]

As an emerging network architecture and technology, mobile edge computing (MEC) can alleviate the tension between the computation-intensive applications and the resource-constrained mobile devices. However, most available studies on computation offloading in MEC assume that the edge severs host various applications and can cope with all kinds of computation tasks, ignoring limited computing resources and storage capacities of the MEC architecture. To make full use of the available resources deployed on the edge servers, in this paper, we study the cross-server computation offloading problem to realize the collaboration among multiple edge servers for multi-task mobile edge computing, and propose a greedy approximation algorithm as our solution to minimize the overall consumed energy. Numerical results validate that our proposed method can not only give near-optimal solutions with much higher computational efficiency, but also scale well with the growing number of mobile devices and tasks. [ABSTRACT FROM AUTHOR]

Orthogonal frequency-division multiplexing (OFDM) is an attractive multicarrier technique for the simplicity of equalization and high data throughput. However, the transmitted OFDM signal has a very high peak-to-average power ratio (PAPR), which severely degrades the performance of practical OFDM systems and reduces the efficiency of high-power amplifiers (HPA). The selected mapping (SLM) scheme is an effective PAPR reduction method of OFDM signals. However, this approach usually requires side information (SI) transmission, which increases the difficulty of the hardware implementation with high complexity and reduces the data transmission rate. In this paper, based on designing phase rotation vectors in the time domain, a novel blind SLM method with low complexity is proposed to reduce the PAPR of OFDM signals. At the transmitter, the proposed method properly designs the phase rotation vectors in the time domain, which can be considered as an equivalent wireless channel without SI transmission. At the receiver, the effect of phase rotation vectors can be removed by the conventional channel estimation method, and the data demodulation processing can be easily performed by the frequency domain equalization. Simulation results show that the proposed scheme can achieve low complexity in PAPR reduction and has great robustness in bit error rate (BER) performance compared to the other low-complexity SLM PAPR schemes. [ABSTRACT FROM AUTHOR]

A novel precoding-based initial ranging signal is presented for the successive multiuser detection and interference cancellation (SMUD) algorithm in OFDMA uplink systems. The ranging codes in the multiple ranging symbols are coded by the precoding matrix. The performance of the SMUD algorithm is greatly improved by using the decoded signal of the received precoded ranging signal. [ABSTRACT FROM AUTHOR]

Classical molecular dynamics simulations have been performed to study the atomic structures and thermal expansion of coordination shells in solid and liquid Invar alloys. Analysis of atomic structures reveals that there is an attraction between Fe-Ni nearest pairs, and that structural order still exists in the liquid Invar alloy. Fe—Ni bonds are found to have the smallest thermal expansion in the solid Invar alloy among three types of bonds, which plays an important role in the Invar effect. We also discover that the thermal expansion coefficient will gradually get close to the macroscopic level as the coordination shell number increases in Invar alloys. It is until the 5th coordination shell in the solid state and the 4th coordination shell in the liquid state that the thermal expansions of the coordination shells can reach the macroscale value. This study further promotes the understanding of the thermal expansions from the atomic scale. [ABSTRACT FROM AUTHOR]

Exploring lead‐free candidates and improving efficiency and stability remain the obstacle of hybrid organic‐inorganic perovskite‐based devices commercialization. Traditional trial‐and‐error methods seriously restrict the discovery especially for large search space, complex crystal structure and multi‐objective properties. Here, the authors propose a multi‐step and multi‐stage screening scheme to accelerate the discovery of hybrid organic‐inorganic perovskites A2BB′X6 from a large number of candidates through combining machine learning with high‐throughput calculations for pursuing excellent efficiency and thermal stability in solar cells. Followed by a series of screenings, the structure‐property relationships mapping A2BB′X6 properties are built and the predictions are close to reported experimental results. Successfully, four experimental‐feasibly candidates with good stability, high Debye temperature and suitable band gap are screened out and further verified by density‐functional theory calculations, in which the predicted efficiency for three lead‐free candidates ((CH3NH3)2AgGaBr6, (CH3NH3)2AgInBr6 and (C2NH6)2AgInBr6) achieves 20.6%, 19.9% and 27.6% due to ultrabroadband absorption region ranging from UVC to IRC with excitonic radiative combination rates as low as 10 ps, large or intermediate polarons form with properties similar to CH3NH3PbI3 and the calculated thermal conductivities are 5.04, 4.39 and 5.16 Wm−1K−1, respectively, with Debye temperatures larger than 500 K, beneficial for suppression of both nonradiative combination and heat‐induced degradation. [ABSTRACT FROM AUTHOR]

Exploring lead‐free candidates and improving efficiency and stability remain the obstacle of hybrid organic‐inorganic perovskite‐based devices commercialization. Traditional trial‐and‐error methods seriously restrict the discovery especially for large search space, complex crystal structure and multi‐objective properties. Here, the authors propose a multi‐step and multi‐stage screening scheme to accelerate the discovery of hybrid organic‐inorganic perovskites A2BB′X6 from a large number of candidates through combining machine learning with high‐throughput calculations for pursuing excellent efficiency and thermal stability in solar cells. Followed by a series of screenings, the structure‐property relationships mapping A2BB′X6 properties are built and the predictions are close to reported experimental results. Successfully, four experimental‐feasibly candidates with good stability, high Debye temperature and suitable band gap are screened out and further verified by density‐functional theory calculations, in which the predicted efficiency for three lead‐free candidates ((CH3NH3)2AgGaBr6, (CH3NH3)2AgInBr6 and (C2NH6)2AgInBr6) achieves 20.6%, 19.9% and 27.6% due to ultrabroadband absorption region ranging from UVC to IRC with excitonic radiative combination rates as low as 10 ps, large or intermediate polarons form with properties similar to CH3NH3PbI3 and the calculated thermal conductivities are 5.04, 4.39 and 5.16 Wm−1K−1, respectively, with Debye temperatures larger than 500 K, beneficial for suppression of both nonradiative combination and heat‐induced degradation. [ABSTRACT FROM AUTHOR]

Exploring lead‐free candidates and improving efficiency and stability remain the obstacle of hybrid organic‐inorganic perovskite‐based devices commercialization. Traditional trial‐and‐error methods seriously restrict the discovery especially for large search space, complex crystal structure and multi‐objective properties. Here, the authors propose a multi‐step and multi‐stage screening scheme to accelerate the discovery of hybrid organic‐inorganic perovskites A2BB′X6 from a large number of candidates through combining machine learning with high‐throughput calculations for pursuing excellent efficiency and thermal stability in solar cells. Followed by a series of screenings, the structure‐property relationships mapping A2BB′X6 properties are built and the predictions are close to reported experimental results. Successfully, four experimental‐feasibly candidates with good stability, high Debye temperature and suitable band gap are screened out and further verified by density‐functional theory calculations, in which the predicted efficiency for three lead‐free candidates ((CH3NH3)2AgGaBr6, (CH3NH3)2AgInBr6 and (C2NH6)2AgInBr6) achieves 20.6%, 19.9% and 27.6% due to ultrabroadband absorption region ranging from UVC to IRC with excitonic radiative combination rates as low as 10 ps, large or intermediate polarons form with properties similar to CH3NH3PbI3 and the calculated thermal conductivities are 5.04, 4.39 and 5.16 Wm−1K−1, respectively, with Debye temperatures larger than 500 K, beneficial for suppression of both nonradiative combination and heat‐induced degradation. [ABSTRACT FROM AUTHOR]

With the continuous development of fifth-generation technology, the number of mobile terminal Internet of Things devices has increased exponentially. How to effectively improve the throughput of fifth-generation systems has become a challenge. In the Internet of Things networks, ultra-dense networks and non-orthogonal multiple access technology have drawn extensive attention in recent years, because they can achieve multiplexing from the space domain and power domain. To improve the throughput of the system, this article combines non-orthogonal multiple access with ultra-dense networks technology and considers the orthogonal frequency division multiplexing non-orthogonal multiple access–based ultra-dense networks with multiple base stations and multiple Internet of Things devices. In particular, first, we build the network model and channel model. Second, we construct the downlink transmission rate maximizing problem subject to the total power. Then, to solve this problem, we divide it into three sub-problems: device grouping, inter-sub-band power allocation, and intra-sub-band power allocation problems. Solving these sub-problems, we obtain the optimal power allocation schemes by jointly employing channel-state sorting–pairing algorithm, water-filling algorithm, and convex optimization theory. Finally, numerical simulations are conducted to validate the performance of our proposed optimal downlink power allocation scheme. Experimental results show that the total throughput of the system has been significantly improved. [ABSTRACT FROM AUTHOR]

• Ru@G and Ru@thiol nanoparticles were prepared by chemical reduction methods. • Ru@G exhibited a specific capacitance of 1013 f g −1 at 0.004 V s −1 scan rate. • Ru@G achieved an energy density of 34.8 W kg−1 at a power density of 1.79 × 105 W kg−1. • The capacitance of Ru@G can retain 94.9% after 10,000 cycles. • Ru@thiol showed exponentially reduced capacitance as the growth of carbon chain. Ru nanoparticles (Ru@G, Ru@HT, Ru@DT, and Ru@OT) were prepared by facile chemical reduction of RuCl 3 and graphene or thiols. The morphologies and structures of these Ru nanoparticles were ascertained by TEM, FTIR, UV–vis, and XPS, confirming the metallic Ru cores were capped by graphene or thiols. Their applications for supercapacitors were investigated in 0.5 M H 2 SO 4 electrolyte, using cyclic voltammetry, galvanostatic charging-discharging test, and electrochemical impedancemetry. Compared as Ru@HT, Ru@DT, and Ru@OT nanoparticles, Ru@G exhibited greatly improved electrochemical performance and stability. It showed a specific capacitance of 1013 F g −1 at 0.004 V s −1, an energy density of 34.8 W kg−1 at the power density of 1.79 × 105 W kg−1, the capacitance retention of 94.9% after 10,000 cycles. The peripheral graphene has good stability and excellent electrical conductivity, so it can provide Ru core stable protection as well as good electron transfer routes, thus Ru@G are suitable for implementation in electrochemical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The introduction of logistics theory and logistics technology has made the government and enterprises gradually realize that the development of logistics has an important strategic role, which can effectively solve the changing needs of users, optimize resource allocation, improve the investment environment, and enhance the overall strength and overall competitiveness of the regional economy. This paper carries out matrix–vector multiplication operations and weight update operations, designs a perceptron neural network model, and realizes a simulation platform based on MLP neural network. Moreover, on the basis of the standard MLP neural network, this paper proposes to use the deep learning training mechanism to improve the MLP neural network, which provides effective technical support for the improvement of the prediction model. In addition, through the fusion of deep learning and MLP neural network, an MLP neural network with three hidden layers is determined. Finally, this paper builds a model based on the MLP neural network algorithm, selects the RBF kernel function as the kernel function of the model by referring to the relevant literature, and uses PSO to optimize the combination of parameters. It can be seen from the result of the evaluation index that each evaluation index is relatively small. The result shows that the prediction is accurate, and the empirical result shows the feasibility of the model to predict the demand for industrial logistics in Shanxi Province. [ABSTRACT FROM AUTHOR]

Herpes simplex virus type I (HSV-1) infection causes inflammation in the cornea known as herpes simplex virus keratitis (HSK), a common but serious corneal disease. It is not entirely clear whether the virus during recurring infection comes from the trigeminal ganglia or the eye tissue, including the retina and ciliary ganglion. Because the tree shrew is closely related to primates and tree shrew eye anatomic structures are similar to humans, we studied HSV-1 corneal infection in the tree shrew. We found that HSK symptoms closely mimic those found in human HSK showing typical punctiform and dendritic viral keratitis during the acute infection period. Following the HSV-specific lesions, complications such as stromal scarring, corneal thickening (primary infection), opacity, and neovascularization were observed. In the tree shrew model, following ocular inoculation, the cornea becomes infected, and viral protein can be detected using anti-HSV-1 antibodies in the epithelial layer and retina neuronal ganglion cells. The HSV-1 transcripts, ICP0, ICP4, and LAT can be detected at 3 days post-infection (dpi), peaking at 5 dpi. After 2 weeks, ICP4 and ICP0 transcripts are reduced to a basal level, but the Latency Associated Transcripts (LATs) continue to accumulate. Interestingly, after the acute infection, we still detected abundant active HSV-1 in tree shrew eyes. Further, we found HSV-1 persistent in the ciliary ganglion and cornea. These findings are discussed in support of the tree shrew as a non-human primate HSK model, which could be useful for mechanistic studies of HSK. [ABSTRACT FROM AUTHOR]

Graphical abstract Wetting transition and controllable coalescence dynamics can be achieved by subjecting the substrate to vibrating. Highlights • Vibration-induced wetting transition is investigated. • Well-wetting, weak-wetting and dewetting states can be switched. • A theoretical model to interpret wetting transition is established. • Vibration-induced wettability transition can control the coalescence. Abstract Controllable wettability of liquids has always been attached great significance to a wide range of applications in both industrial and technological processes. Here, we report a simple and novel approach to achieve reversible and switchable wettability through the vibration of substrate. Results showed that with the increase of the vibration frequency (f), the wetting state of the liquid metal gradually transform into wetting/dewetting mixed state, and finally becomes complete dewetting state. More importantly, on the basis of our established model (involving vibration amplitude, liquid-substrate interaction), we further interpret and predict the wetting status and the wetting transition procedure of the given droplet. Additionally, the vibration-induced wettability transition can be applied to control the coalescence dynamics, which generates three patterns: free-coalescence, semifree-coalescence, restricted-coalescence. Our work would develop a new strategy to control the surface wettability by vibrating the substrate, without any mechanical or chemical modifications, which could provide guidance in the manipulation of drop dynamics. [ABSTRACT FROM AUTHOR]

Spicy foods elicit a pungent or hot and painful sensation that repels almost all mammals. Here, we observe that the tree shrew (Tupaia belangeri chinensis), which possesses a close relationship with primates and can directly and actively consume spicy plants. Our genomic and functional analyses reveal that a single point mutation in the tree shrew’s transient receptor potential vanilloid type-1 (TRPV1) ion channel (tsV1) lowers its sensitivity to capsaicinoids, which enables the unique feeding behavior of tree shrews with regards to pungent plants. We show that strong selection for this residue in tsV1 might be driven by Piper boehmeriaefolium, a spicy plant that geographically overlaps with the tree shrew and produces Cap2, a capsaicin analog, in abundance. We propose that the mutation in tsV1 is a part of evolutionary adaptation that enables the tree shrew to tolerate pungency, thus widening the range of its diet for better survival. [ABSTRACT FROM AUTHOR]

Herpes Simplex Virus type I (HSV-1) latently infects peripheral nervous system (PNS) sensory neurons, and its reactivation leads to recurring cold sores. The reactivated HSV-1 can travel retrograde from the PNS into the central nervous system (CNS) and is known to be causative of Herpes Simplex viral encephalitis. HSV-1 infection in the PNS is well documented, but little is known on the fate of HSV-1 once it enters the CNS. In the murine model, HSV-1 genome persists in the CNS once infected through an ocular route. To gain more details of HSV-1 infection in the CNS, we characterized HSV-1 infection of the tree shrew ( Tupaia belangeri chinensis) brain following ocular inoculation. Here, we report that HSV-1 enters the tree shrew brain following ocular inoculation and HSV-1 transcripts, ICP0, ICP4, and LAT can be detected at 5 days post-infection (p.i.), peaking at 10 days p.i. After 2 weeks, ICP4 and ICP0 transcripts are reduced to a basal level, but the LAT intron region continues to be expressed. Live virus could be recovered from the olfactory bulb and brain stem tissue. Viral proteins could be detected using anti-HSV-1 antibodies and anti-ICP4 antibody, during the acute stage but not beyond. In situ hybridization could detect LAT during acute infection in most brain regions and in olfactory bulb and brain stem tissue well beyond the acute stage. Using a homogenate from these tissues' post-acute infection, we did not recover live HSV-1 virus, supporting a latent infection, but using a modified explant cocultivation technique, we were able to recover reactivated virus from these tissues, suggesting that the HSV-1 virus latently infects the tree shrew CNS. Compared to mouse, the CNS acute infection of the tree shrew is delayed and the olfactory bulb contains most latent virus. During the acute stage, a portion of the infected tree shrews exhibit symptoms similar to human viral encephalitis. These findings, together with the fact that tree shrews are closely related to primates, provided a valuable alternative model to study HSV-1 infection and pathogenesis in the CNS. [ABSTRACT FROM AUTHOR]

• The current-voltage curves of the molecular devices before and after 90-degree rotation are symmetrical. • Rotating the cluster TiC can switch the device from a low conductivity state to a high conductivity state. • Negative differential resistance in the Device Ti 9 C 9. In this paper, density functional theory (DFT) and non-equilibrium Green's function are used to study the electron transport properties of TiC clusters attached to gold electrodes. It has been found that the current-voltage curves of the molecular devices before and after 90-degree rotation are symmetrical in the low bias region. Ti 9 C 13 has excellent electron transport properties and an excellent switching effect. Interestingly, compared to Ti 9 C 13 (with C 2 dimers), Ti 9 C 9 with cubic structure exhibits inferior transport properties due to the different molecular orbital coupling, importantly, it has negative differential resistance (NDR) effect. These results contribute to select molecular connecting and control the coupling between molecules and electrodes, and design molecular devices with unique properties. [ABSTRACT FROM AUTHOR]

Abstract: Corridor engineering is a common approach for wildlife conservation. The influence of the practice on soil properties including nutrients and organic matter, however, remains poorly investigated. In order to predicate the long-term effects of Asian elephant (Elephas maximus L.) conservation corridors (AECC) of the Greater Mekong Sub-region (GMS) on soil properties and functional recovery, we studied the soil comprehensive accumulation ability and estimated total recovery time under two major forest types on which the corridor is built (natural secondary forest and rubber plantation) and one forest type generated by ecological replanting on existing rubber plantation in comparison with soils under primary rain forest and fallow land in Xishuangbanna, Southwest China. Soil samples were taken from five research sites and fifteen soil properties were measured. On a 30-year basis, soil recovery differed significantly in the three regimes. The natural secondary forest regime had the highest comprehensive accumulation of about 92% and the shortest estimated recovery time (37–40 years). In contrast, the monoculture rubber plantation, despite constant fertilizer and management input, yielded the poorest recovery result of about 75% and the longest recovery time (95–100 years). From the perspective of soil recovery, this regime appears unsustainable. However, the ecological replanting using local rain forest trees and shrubs thereby to build forest structure complexity and diversity on the monoculture rubber plantation improved comprehensive accumulation ability of about 8% (from 75% to 83%) and shortened the recovery time (40 years). The results suggest that the corridor engineering by natural secondary forest regime or by ecological replanting of monoculture rubber plantation can serve as effective regimes for soil properties recovery. [Copyright &y& Elsevier]

• Amorphous silicon has a higher oxidation rate than the crystalline silicon. • Amorphous-structure-promoted oxidation of silicon stems from structural defects. • Structural defects reduce the dissociation barrier of oxygen and promote diffusion. • Structural defects induce an island-like nucleation of oxide on amorphous silicon. • Crystallized oxide film on the amorphous silicon has smaller grain size. The atomic arrangements in the crystalline silicon (c-Si) and amorphous silicon (a-Si) are distinctly different, which affects the surface restructuring during oxidation and the resulting Si/oxide interfacial structures. Here, based on reactive molecular dynamics simulations, we elucidate that the amorphous-structure-promoted oxidation of silicon is associated with the structural defects in the a-Si. Randomly distributed structural defects on the surface of the a-Si not only induce a "selective adsorption" of O 2 which facilitates the dissociation, but also cause the oxides to nucleate like islands and combine into the oxide film, in comparison to the layer-by-layer oxide growth on the c-Si surface. Moreover, the defects in the a-Si provide an easy pathway for the penetration of oxygen into the a-Si structure, thus resulting in higher oxidation rate and thicker oxide layer than those in the c-Si. The phase separation and thermal crystallization of the amorphous oxide films at high temperatures are also discussed in depth. This study provides a better understanding of the crucial role of atomic structure in determining the oxidation mechanism, the oxide growing kinetics and the resulting oxide structures on silicon, which suggests the key to fabricate ultra-thin oxide films to fulfill the specific requirements of microelectronic and photovoltaic applications. [ABSTRACT FROM AUTHOR]

• Relationship between magnetic moment and local surrounding is studied. • Antiferromagnetic alignment is taken into consideration. • The variation of atomic volume with respect to the atomic magnetic moment is investigated. • Magnetic free energy as a function of lattice constant and temperature is investigated. Magnetism of Fe-Ni system is calculated from the first-principles. Results show that the atomic magnetic moments are determined by their local surrounding atoms. In both FM and AFM cases, the Fe atomic magnetic moment declines with increasing number of Fe atoms in its local surroundings. The relation between atomic volume and atomic magnetic moment indicates that Fe-rich local surroundings would cause relatively small volumes. Our work is of significance to understanding the relation between the local surroundings with anomalous thermal expansion coefficient in the Invar alloy. [ABSTRACT FROM AUTHOR]

Location information is a key issue for applications of the Internet of Things. In this paper, we focus on mobile wireless networks with moving agents and targets. The positioning process is divided into two phases based on the factor graph, i.e., a prediction phase and a joint self-location and tracking phase. In the prediction phase, we develop an adaptive prediction model by exploiting the correlation of trajectories within a short period to formulate the prediction message. In the joint positioning phase, agents calculate the cooperative messages according to variational message passing and locate themselves. Simultaneously, the average consensus algorithm is employed to realize distributed target tracking. The simulation results show that the proposed prediction model is adaptive to the random movement of nodes. The performance of the proposed joint self-location and tracking algorithm is better than the separate cooperative self-localization and tracking algorithms. [ABSTRACT FROM AUTHOR]