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Achieving efficient thermal management urges to exploit high-thermal-conductivity materials to satisfy the boosted demand of heat dissipation. It is critical to adopt standardized characterization protocols to evaluate the intrinsic thermal conductivity of thermal management materials. However, for the most representative laser flash method, the lack of standard measurement methodology and systematic description on the thermal diffusivity and influencing factors has led to significant deviations and confusion of the thermal conduction performance in the emerging thermal management application. Here, the measurement error factors of thermal diffusivity by the common laser flash analyzer (LFA) are discussed. Taking high-thermal-conductivity graphitic film (GF) as a typical case, the key factors are analyzed to guide the measurement protocol of related carbon-based thermal management materials. The basic principle of the LFA measurement, actual pre-processing conditions, instrument parameters setting, and data analysis are elaborated for accurate measurements. Furthermore, the graphene thick films and common isotropic materials are also extended to meet various thermal measurement requirements. Based on the existing practical problems, we propose a feasible test flow to achieve a unified and standardized thermal conductivity measurement, which is beneficial to the rapid development of carbon-based thermal management materials.

The large-scale online supermarket is a newly emerging online retailing mode which brings great convenience to people. Online supermarkets are characterized by having large amounts of daily orders with potentially multiple items, diverse delivery times, and a high order-split rate. Multiple shipments for one order caused by order splitting result in high cost and disturbance and a large number of discarded consumable packages at online retailers and customers, causing severe damage to the environment. Accordingly, research on split-order consolidation fulfilment is critical for the advancement of the practice and theory in the context of highly complex online retailing. This paper first analyzes the characteristics and the challenges associated with the split-order consolidation problem that online supermarket is confronting and summarizes the new operational process of split-order consolidation fulfilment. Then, a time-space network optimization model is built, and its corresponding solution algorithm is presented to solve the questions of where and when to consolidate the split orders. Finally, the computation results of the numerical experiments are provided to verify the effectiveness of the algorithm, and a sensitivity analysis of the relevant parameters is performed. This work highlights the effect of order consolidation processes and fulfilment methods on the order fulfilment decision-making for online supermarkets. The purpose of this article is to help pave the way for more effective online supermarket management and order implementation.

In urban rail transit systems, passenger flow assignment is vital for administrators and designers. Many approaches using evaluation indicators seek to improve assignment accuracy. However, such approaches suffer from the inefficiency in traffic flow computation, especially in large-scale networks. K-shortest path searching is an essential component in flow assignment; its complexity depends on the network scale. This study proposes a simplified framework with a bi-layer network (BL-NSF) to find the K-shortest path as early as possible to improve the speed of flow assignment while meeting accuracy requirements. First, a bi-layer transformation operator is developed. Specifically, a first-layer transformation operator employs the station extraction function to simplify the type of stations. The network is, therefore, first reduced since non-transfer stations are extracted. Second, a second-layer transformation operator with a path filter function is designed to eliminate the non-effective connection structure. Thus, the complexity of the network is further reduced, and the streamline structure of the topology rail network is constructed. Sequentially, we search the K-shortest path by executing four designed matching mechanisms and a modified Yen’s algorithm, a traditional algorithm used in the existing transit system. After that, we perform passenger flow calculations for stations, links, and lines. Finally, a series of experiments is run on the test network to verify the effectiveness and efficiency of BL-NSF on the flow assignment. The results demonstrate that the proposed BL-NSF performs better and is more competitive than the state-of-the-art algorithms.

Presenting the first investigation into the structurally bubbling-failure mechanism of graphitic film during cyclic liquid nitrogen shocks.Proposing an innovative design about seamless heterointerface constructing a Cu-modified structure.Inventing a new ultra-stable species of highly thermally conductive films to inspire new techniques for efficient and extreme thermal management.

Endosperm as the storage organ of starch and protein in cereal crops largely determines grain yield and quality. Despite the fact that several pentatricopeptide repeat (PPR) proteins required for endosperm development have been identified in rice, the molecular mechanisms of many P-type PPR proteins in endosperm development remains unclear. Here, we isolated a rice floury endosperm mutant ppr5that developed small starch grains and an abnormal aleurone layer, accompanied by decreased starch, protein, and amylose contents. Map-based cloning combined with a complementation test demonstrated that PPR5encodes a P-type PPR protein that is localized to the mitochondria. The mutation in PPR5caused reduced splicing efficiency of mitochondrial NADH dehydrogenase 4(nad4) gene intron 3 and reduced complex I assembly and activity. Loss of PPR5function greatly up-regulated expression of alternative oxidases (AOXs), reduced ATP production, and affected mitochondrial morphology. We demonstrate that PPR5, as a P-type PPR protein, is required for mitochondrial function and endosperm development by controlling the cis-splicing of mitochondrial nad4intron 3.

Unmanned aerial vehicle (UAV)-assisted mobile edge computing (MEC) has been considered as a promising approach to offering extensive coverage and massive computing capacities for Internet of Things (IoT). In this letter, we propose a novel multi-UAV-assisted multi-access MEC model by allowing each IoT user to offload task bits to multiple MEC servers deployed at UAVs simultaneously for parallel computing, which can effectively reduce the energy consumption of users and UAVs. The weighted sum energy consumption of UAVs and users is minimized by jointly optimizing the bit allocation, transmit power, CPU frequency, bandwidth allocation and UAVs’ trajectories. Due to the non-convexity of the formulated problem, it is decomposed into two subproblems and a joint resource allocation and trajectory design algorithm is proposed by alternative optimization. Simulation results show that our proposed algorithm with multiple radio access outperforms the fixed trajectory, fixed bandwidth allocation and the single access schemes.

Chronic kidney disease has attracted great attention as a public health disease and is mainly caused by the retention of uremic toxins in the body. Urea is a kind of representative toxin with high solubility and cannot be removed easily; in fact, no suitable absorbers have been found to remove urea by physical adsorption. Herein, we prepare urease-immobilized magnetic graphene oxide as a recyclable nanocatalyst for effective urea removal in blood purification, which shows great removal ability toward urea (2194 ± 110 mg/g). The clearance ratio is over 80% even for a high concentration urea solution of 80 mg/mL, and it is 77% for collected dialysate from a clinic. The nanocatalyst exhibits good reusability and storage stability. Furthermore, a series of blood-related tests indicate that the prepared nanocatalyst has good blood compatibility. Thus, the urease-immobilized recyclable nanocatalyst has great potential for effective and safe urea removal in blood purification.

AbstractNigrosporais a monophyletic genus belonging to Apiosporaceae. Species in this genus are phytopathogenic, endophytic, and saprobic on different hosts. In this study, leaf specimens with disease symptoms were collected from host plants from the Shandong Peninsula, China. The fungal taxa associated with these leaf spots were studied using morphology and phylogeny based on ITS, TEF1, and TUB2 gene regions. In this article, we report on the genus Nigrosporawith N. gorlenkoana, N. oryzae, N. osmanthi, N. rubi, and N. sphaericaidentified with 13 novel host associations including crops with economic importance such as bamboo and Chinese rose.

High-performance thermal interface materials (TIMs) are highly desired for high-power electronic devices to accelerate heat dissipation. However, the inherent trade-off conflict between achieving high thermal conductivity and excellent compliance of filler-enhanced TIMs results in the unsatisfactory interfacial heat transfer efficiency of existing TIM solutions. Here, we report the graphene fiber (GF)-based elastic TIM with metal-level thermal conductivity via mechanical–electric dual-field synergistic alignment engineering. Compared with state-of-the-art carbon fiber (CF), GF features both superb high thermal conductivity of ∼1200 W m–1K–1and outstanding flexibility. Under dual-field synergistic alignment regulation, GFs are vertically aligned with excellent orientation (0.88) and high array density (33.5 mg cm–2), forming continuous thermally conductive pathways. Even at a low filler content of ∼17 wt %, GF-based TIM demonstrates extraordinarily high through-plane thermal conductivity of up to 82.4 W m–1K–1, exceeding most CF-based TIMs and even comparable to commonly used soft indium foil. Benefiting from the low stiffness of GF, GF-based TIM shows a lower compressive modulus down to 0.57 MPa, an excellent resilience rate of 95% after compressive cycles, and diminished contact thermal resistance as low as 7.4 K mm2W–1. Our results provide a superb paradigm for the directed assembly of thermally conductive and flexible GFs to achieve scalable and high-performance TIMs, overcoming the long-standing bottleneck of mechanical–thermal mismatch in TIM design.

A highly enantioselective catalytic reduction of pyrazolo[1,5-a]pyrimidine to zanubrutinib has been realized by the Ir/(R)-t-Bu-FcPhox complex. This chiral product could be obtained in up to >99% eein the asymmetric transformation without any other additives, providing a new route for the asymmetric synthesis of zanubrutinib.

In this letter, the resource allocation problem for uplink multi-carrier non-orthogonal multiple access (NOMA) in device-to-device (D2D) underlaid cellular networks is investigated. Due to the existence of D2D pairs, NOMA users are subject to varying degrees of interference. We formulate the problem as a Nash bargaining game to maximize the Nash product of each user. We propose an iterative algorithm applying Karush–Kuhn–Tucker conditions to solve the power allocation problem and modeling the user clustering as a Hedonic coalition game. Simulation results verify the convergence of the proposed algorithms. Besides, the algorithms achieve near-optimal performance compared to exhaustive search method and the throughput and fairness in NOMA are both higher than those in orthogonal multiple access.

As a technology to reduce cost and power consumption, dual gate and precharge driving mode has been widely used in TFT ‐ LCD products, however, color shift appear during the V‐T test in some special array structure product, so we conduct an analysis. By experiment, we prove that there are two feedback voltage in such design , one is caused by the coupling capacitance between gate electrode and source electrode, the other is caused by the coupling capacitance between pixel electrode and adjacent gate electrode. Feedback voltage are different in different pixels, so V‐T curve is different, the different feedback voltage lead to abnormal color.The paper propose the color shift phenomenon may bring defect to the display quality, which has an important reference significance to the choice of dual gate and precharge driving mode.

With global climate change posing a major threat to human society, many countries have elevated “carbon neutrality” to a national strategy and put forward a vision of a zero-carbon future. In this process, environmental regulation (ER) and renewable energy technology innovation (RET) are important factors that contribute to achieving the carbon neutrality goal. Thus, this study employs a spatial econometric technique model to investigate the direct and indirect effects of ER and RET on environmental sustainability from both theoretical and empirical dimensions based on panel data of 30 Chinese provinces during 1998–2020. The results show that ER is not conducive to the improvement of environmental quality in local and neighboring areas, but it is beneficial to the reduction of CO2emissions when the level of economic development is greater than the critical threshold of 9.126, i.e., the “inverted U-shaped” curve relationship. On the contrary, RET has a beneficial impact on the environment, but when the economic development level is greater than the critical threshold of 8.790, the carbon reduction effect of RET is reduced. Thus, the significance and magnitude of the carbon reduction effect of ER and RET depend on the regional economic development level, and excessive RE will have a suppressive effect on RET. The paper assisted policy makers in designing a holistic policy to enhance environmental sustainability through ER and RET, especially in the Chinese region.

The oncologic results of laparoscopic nephroureterectomy for pathological tumor stage T2 (pT2) upper tract urothelial carcinoma (UTUC) remain controversial. This study was designed to compare oncologic outcomes of T2 UTUC patients treated with retroperitoneoscopic nephroureterectomy (RNU) or open radical nephroureterectomy. The results showed that RNU represents a safe, minimally invasive procedure, and it produces equally beneficial oncologic results as the traditional, and more risky, open surgery procedure.

This study examines the potential impact of nuclear energy consumption on environmental sustainability in the context of economic globalization using FMOLS, DOLS and panel Granger causality tests with a panel of BRICS countries data for the period 1985–2020 based on the inverted U-curve relationship of the environmental Kuznets curve (EKC) hypothesis. The findings support the panel's EKC hypothesis of an inverted U- curve relationship and suggest that economic growth exacerbates environmental pollution and is detrimental to the improvement of environmental quality in BRICS countries, while economic globalization, nuclear energy and renewable energy consumption tend to improve the environmental quality and play a leading role in reducing environmental pollution. Furthermore, panel Granger causality tests have shown the bi-directional causality of CO2emissions and renewable energy consumption with economic growth. However, unidirectional causality exists from CO2emissions to renewable energy consumption, nuclear energy consumption to economic growth, and renewable energy consumption to economic globalization. This study suggests that the best option for improving the environmental quality of BRICS countries to combat global warming in the light of long-term sustainable economic globalization is to achieve a mix of nuclear and renewable energy sources in order to ensure and meet the needs of economic and environmental sustainability, thereby effectively achieving the goals of “decarbonization” and “emission reduction”.