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The rapid development of high power density devices requires more efficient heat dissipation. Recently, two-dimensional layered materials have attracted significant interest due to their superior thermal conductivity, ease of production and chemical stability. Among them, hexagonal boron nitride (h-BN) is electrically insulating, making it a promising thermal management material for next-generation electronics. In this work, we demonstrated that an h-BN thin film composed of layer-by-layer laminated h-BN nanosheets can effectively enhance the lateral heat dissipation on the substrate. We found that by using the BN-coated glass instead of bare glass as the substrate, the highest operating temperature of a reduced graphene oxide (RGO) based device could increase from 700 °C to 1000 °C, and at the same input power, the operating temperature of the RGO device is effectively decreased. The remarkable performance improvement using the BN coating originates from its anisotropic thermal conductivity: a high in-plane thermal conductivity of 14 W m−1 K−1 for spreading and a low cross-plane thermal conductivity of 0.4 W m−1 K−1 to avoid a hot spot right underneath the device. Our results provide an effective approach to improve the heat dissipation in integrated circuits and high power devices.

Lead (Pb)-based halide perovskites with enhanced solar cell performance and a larger open-circuit voltage were experimentally observed after the treatment of crystal surfaces with pyridine and amine-functionalized molecules. We model the Pb–I2 terminated perovskite surfaces using density-functional theory and find that two small organic molecules, pyridine and ethylamine, interact with the surfaces and tune their electronic band gaps. When dopants on surfaces have parallel or antiparallel polarities with the orientation of methylammonium (MA = CH3NH3) molecules in bulk, the electronic properties of the perovskite surfaces will be remarkably different. We demonstrate that ethylamine and pyridine with antiparallel polarities can enlarge the band gaps of perovskite surfaces. The change of electronic properties is ascribed to the cancellation of the dipole moments caused by the pyridine/ethylamine and methylammonium molecules on surfaces. We further vary the polarities of MA molecules by interchanging the C and N atoms in a symmetric fashion for showing the influence of polarization on total energies, electronic properties and charge distributions.

Boron monolayers have been increasingly attractive, while it is still a challenge to understand their structural stabilities, due to electron deficiency and multi-center bonds. In this work, we propose the average electron compensation (AEC) mechanism for boron monolayers based on high-throughput first-principles calculations. It is found that the AEC parameter (λ) tends to be zero for the stable free-standing boron monolayers. In addition, this mechanism can quantitatively describe the stability of boron monolayers on various metal substrates, providing direct suggestions for experimentalists to synthesize various boron monolayers for practical applications.

This paper describes a tree-ring width chronology that spans the past 4650 years, established using the recently developed eigenanalysis technique. The aim is to show whether this eigenanalysis method enables the extraction of long-term tree-growth variations that are due to climatic changes, from a large dataset comprising 1263 tree-ring width records sampled from the highlands of Western China. In order to exclude the so-called growth rate/life span association effect, tree-ring width records were sorted into six subsets, based on the life spans of the trees sampled: 200–400, 400–600, 600–800, 800–1000, 1000–1500 years old, and trees older than 1500 years. Some partial chronologies were created, by pairing the set of all tree samples (living, dead, archaeological remains) with the living trees belonging to each subset. We computed the contours of tree-growth variations (on both 100-year and longer time scales) for each subset, ending with six pairs of these partial subset chronologies. Two sums of all these partial chronologies thus yielded a record of precipitation variations over a period ranging from 2627 BCE up to 2012 CE. It was found that this record shows a high degree of similarity to the existing chronology produced using the regional curve standardization (RCS) method applied to the same dataset, indicating that the eigenvalue chronology is capable of faithfully extracting long-term climatic variations. This also confirms that the first eigenvector represents the growth pattern that is characteristic of each biologically unique tree as well as the micro-environment of each tree stand. The variations observed over the last millennium seem to be connected to a cycle of solar activity with a period of ∼200 years. However, a clear lack of correspondence between solar activity and tree growth prior to 1000 CE indicates that the recent consistency may be coincidental. We believe that the eigenanalysis technique is readily applicable to other kinds of tree-ring datasets from different parts of the world.

New types of synthetic municipal solid wastes (MSWs) were developed, exhibiting engineering characteristics similar to those of real MSWs at different states of degradation in terms of total unit weight, void ratio, water content, compressibility, permeability, stress–strain relationship, and shear strength. Using these synthetic MSWs, several centrifuge model tests on the stability of geosynthetics-lined landfills with rising water levels were performed. The test results revealed the developing processes of MSW landfill failures induced by rising water levels. In most tests, a continuous slide occurred once a critical water level was attained. The ratio of critical water level and landfill height was 0.75–0.92 for present model tests using fresh or partly degraded synthetic MSWs with landfill slope ratio of 1:1–1:3, increasing with the increases of MSW degradation states and decreases of the slope ratio. An engineered berm increased the critical water level by 1.3%–9.5%. The landfills without an engineered berm tended to slide along the bottom liner; however, for normal landfills with an engineered berm and a slope ratio of 1:3, penetrating cracks developed when the failures occurred. These results provide a good reference for water level and stability control of the landfill, and the construction of an engineered berm is suggested to improve the stability of these landfills.

Objective To observe the clinical efficacy of excitement transfer therapy for insomnia. Methods According to the inclusion criteria, 32 patients, selected from Guoyitang, affiliated Zhongshan Hospital Yanwu Branch of Xiamen University from May to October, 2016, were diagnosed with insomnia and included in this study. All the patients were treated by adopting the excitement transfer therapy, i.e. cluster needling was carried out at the acupoints of wrist and ankle in the manner of penetration needling, and combined with sliding-cupping at governor vessel and bladder meridian on the back. All the subjects were treated for 3 times per week, and treatment for 6 times was considered as 1 course of treatment. The curative effect was observed after treatment for 2 courses, and follow-up visit was performed for two months after treatment. Efficacy evaluation criteria were established by reference to Guidelines of Clinical Research on Chinese New Herbal Medicine (Trial) Results Cured: 11 cases (34%), markedly effective: 16 cases (50%), effective: 4 cases (13%), ineffective: 1 case. The total effective rate was up to 97%. There was no relapse during two months after the treatment. Conclusion The efficacy of excitement transfer therapy for insomnia was significant, which was worthy of clinical promotion and application.

Transistor heat generation in wide bandgap power amplifier transistors is today in excess of several kW/cm 2 and can result in temperature spikes, or “hotspots,” approaching 100 K in the near-junction region. Novel, high flux cooling techniques are under development to enable successful exploitation of the inherent operational capability of wide bandgap amplifiers. Micro-contact enhanced thermoelectric coolers, using an integral pillar etched directly in the electronic substrate to concentrate cooling on the sub-mm transistor hotspot, is a most promising near-junction thermal management technique. This paper reports an experimental and numerical study of micro-contact enhanced thermoelectric cooling of a 5 kW/cm 2 hotspot on a SiC substrate, demonstrating a “world record” 12 K temperature reduction for such high flux, using a commercial thermoelectric module. Moreover, using the validated numerical model, it is predicted that a 5 kW/cm 2 hotspot could be cooled by up to 30 K using an optimized micro-contact and substrate geometry.

Induced resistance in harvested fruit and vegetables is a superior strategy to reduce postharvest decay. In the present study, Cinnamaldehyde (CA) was applied to investigate for its induced resistance against Penicillium digitatum and Geotrichum citri-aurantii. The results showed that 5250 mg CA/L wax was effective concentration in inducing the resistance of citrus fruit to green mold and sour rot. Wax+ CA (WCA) reduced significantly green mold and sour rot incidences at different exposure times, with 24 h being the optimal exposure time. The host reactions under infection with different pathogens were similar. During initial exposure, treatment with 5250 mg CA/L wax enhanced significantly the activities of phenylalanine ammonia-lyase (PAL), peroxidase (POD), polyphenol oxidase (PPO), β-1, 3-glucanase (GLU) and chitinase (CHT) in the presence of direct contact with the pathogen. Simultaneously, WCA induced an increase in total phenolic, flavanone and dihydroflavonol, flavone and flavonol, and lignin contents. Thus, our results suggest that treatment using 5250 mg CA/L wax can be applied early to control diseases by provoking response reactions in citrus fruit.

Mycotoxins are increasingly considered as micropollutants in the environment. Fumonisins, as one of the most important mycotoxins, cause potential health threats to humans and animals due to their ubiquitous contamination on cereals, fruit, vegetables and other environmental samples around the world. However, the contribution of fumonisins to the interaction of fungi with plant hosts is not still fully understood. Here, we investigated the effect of fumonisin B1 (FB1) on the infection of Fusarium proliferatum on banana fruit and the underlying mechanisms from the host perspective. Our results found that FB1 treatment increased the aggressiveness of F. proliferatum on banana fruit and inhibited the defense ability of banana fruit via decreasing phenylalanine ammonia lyase (PAL), β-1,3-glucanase (GLU) and chitinase (CHI) activities. Meanwhile, FB1 accelerated cell death, indicated by higher relative conductivity, MDA content and higher transcripts of cell death-related genes. FB1 treatment resulted in higher hydrogen peroxide (H2O2) content possibly due to MaRBOHs induction. These consequences accelerated the ROS-dependent cell death, which subsequently result in reduction of disease resistance of banana fruit. Additionally, energy metabolism and MaDORN1s-mediated eATP signaling might involve in FB1-meidiated suppression of banana defense responses. Collectively, results of the current study indicated that FB1 contamination triggered the cell death of banana peel, subsequently instigating the invasion and growth of F. proliferatum on banana fruit. In summary, for the first time, we demonstrated a previously unidentified role of fumonisins as a potential virulence factor of F. proliferatum in modulating fruit defense response, which provides new insight on the biological roles of fumonisins.

Increasingly serious electromagnetic radiation pollution puts forward higher demands on wearable fabrics: high electromagnetic interference (EMI) shielding effectiveness. Besides, the ability for the fabrics to keep the human body warm is also important in a frigid environment. However, there have been few reports on fabrics simultaneously with the two functions so far. Here, a flexible wearable fabric with both excellent EMI shielding and passive radiation heating functions was developed through integrating silver nanowire (AgNW), ferroferric oxide (Fe3O4) nanoparticles, and polydimethylsiloxane (PDMS) onto a commercial fabric. The conductive AgNW networks endowed the fabric with a super-high EMI shielding property of 100.9 dB at the thickness of 450 μm – one noticeable advantage. The passive radiation heating ability was achieved by regulating the spectral selectivity of the fabric (a high solar energy absorptivity of 80.5% at 250–2500 nm, a low mid-infrared emissivity of 0.21 at 7 − 14 μm), so no electric power is needed for the fabric to heat the human body – another prominent advantage. The fabric resulted in a 20.6 °C temperature enhancement of the simulated skin under sunlight in the daytime and a 6.4 °C temperature enhancement in nighttime compared with traditional cotton fabric with the same thickness. Thus, the prepared multifunctional fabric can effectively protect the human body from electromagnetic radiation harm and injury caused by cold climate. This work holds great potential to enlarge the application scope of current EMI shielding fabrics.

We explore potential peer effects in pro-environmental behaviour using Chinese General Social Survey 2013, where individual participations in ten pro-environmental activities are recorded. Instrumental variable regressions suggest that individual pro-environmental behaviour is positively and significantly affected by that of neighbourhood peers. Such effects are robust against alternative estimation procedures and falsification tests. Results further show that, while identified peer effects do function through social networks, such mediation explains only a small portion of the peer effects, which may largely occur among strangers living in the neighbourhood through observation and mimicry. These findings imply that peer effects should be seriously considered in neighbourhood-level interventions to stimulate pro-environmental behaviour more cost-effectively.

Drought is the primary limiting factor for tree growth in arid and semi-arid regions, where it can greatly influence xylem anatomical traits and induce multiple responses to wood development. However, the mechanisms driving xylogenesis and intra-annual density fluctuations (IADFs), as well as the seasonal dynamics of wood development in water-limited environments, are still unclear. In this study, we assessed the kinetics of xylem development weekly in Chinese pine (Pinus tabuliformis) and Qinghai spruce (Picea crassifolia), at two altitudes in the Helan Mountains, semi-arid China. Results indicate that summer drought in June inhibited cambial division and reduced xylogenesis, resulting in only 40% of the xylem developing before August. The onset of abundant precipitation in mid-July reactivated radial growth. This second growth extended the growing season by one month and partly compensated for the negative effect of the drought on growth. E-type IADF were characterized by narrow cells with thick walls, formed during July and early August. The duration of cell enlargement explained 57% of variance in tracheid diameter, showing that it played an important role in determining cell size. In contrast, changes in the cell wall thickness were mainly driven by the rate of secondary wall thickening, which explained 65% of the variance. This study reveals the potential mechanisms for xylem development and E-IADF formation under summer drought in semi-arid China, provides evidence for the plasticity and resistance of Chinese pine and Qinghai spruce under varying environmental conditions, and contributes to our understanding of likely future trends in forest productivity under climate changes.

Based on the first-principles calculations, the stable structures of FexM1-x (M = Y, La) binary alloy have been determined according to the formation enthalpy, and the calculated binding energy of hydrides as a function of chemical potential show that the YFe2H4.5 is stable. The thermodynamic stabilities of target alloys and hydrides at various temperatures have further been confirmed using the quasi harmonic approximation in lattice vibration theory. The nudged elastic band method (NEB) is used to investigate the diffusion of hydrogen atoms at different interstitials. The charge density distribution of YFe2 and YFe2H5 has been analyzed to demonstrate the structural stability and the dehydrogenation process. The elastic modulus of YFe2, YFe2H5, LaFe2 and LaFe2H5 will decrease as the temperature increases, with a weaker anisotropy in the Y–Fe system than that in the La–Fe system.

Tripartite motif containing 16 (TRIM16) is a member of the tripartite motif protein family and functions as a potential tumor suppressor in several cancers. However, the specific function and clinical significance of TRIM16 in colorectal cancer (CRC) remains unclear. In this study, we observed that low TRIM16 expression was detected frequently in primary colorectal cancer (CRC) tissues and was closely associated with a better prognosis. Functional studies demonstrate that TRIM16 overexpression notably inhibits the metastasis abilities of CRC in vivo and in vitro. Mechanistically, our results demonstrated that TRIM16 directly bound and ubiquitinated Snail family transcriptional repressor 1 (Snail), an important transcriptional factor of the epithelial-mesenchymal transition (EMT) process suppressing the EMT in CRC. Additionally, our data revealed that the inhibition effect of TRIM16 on cancer metastasis was dependent on Snail degradation. Collectively, our study is the first to report that TRIM16 plays a crucial anti-tumor role in CRC tumorigenesis. We also provided novel evidence that TRIM16 might act as a prognostic and therapeutic target to assess and inhibit CRC progression.