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This study proposes a bi-level framework for real-time crash risk forecasting (RTCF) for signalised intersections, leveraging the temporal dependency among crash risks of contiguous time slices. At the first level of RTCF, a non-stationary generalised extreme value (GEV) model is developed to estimate the rear-end crash risk in real time (i.e., at a signal cycle level). Artificial intelligence techniques, like YOLO and DeepSort were used to extract traffic conflicts and time-varying covariates from traffic movement videos at three signalised intersections in Queensland, Australia. The estimated crash frequency from the non-stationary GEV model is compared against the historical crashes for the study locations (serving as ground truth), and the results indicate a close match between the estimated and observed crashes. Notably, the estimated mean crashes lie within the confidence intervals of observed crashes, further demonstrating the accuracy of the extreme value model. At the second level of RTCF, the estimated signal cycle crash risk is fed to a recurrent neural network to predict the crash risk of the subsequent signal cycles. Results reveal that the model can reasonably estimate crash risk for the next 20–25 min. The RTCF framework provides new pathways for proactive safety management at signalised intersections. [ABSTRACT FROM AUTHOR]

Informatics paradigms for brain and mental health research have seen significant advances in recent years. These developments can largely be attributed to the emergence of new technologies such as machine learning, deep learning, and artificial intelligence. Data-driven methods have the potential to support mental health care by providing more precise and personalised approaches to detection, diagnosis, and treatment of depression. In particular, precision psychiatry is an emerging field that utilises advanced computational techniques to achieve a more individualised approach to mental health care. This survey provides an overview of the ways in which artificial intelligence is currently being used to support precision psychiatry. Advanced algorithms are being used to support all phases of the treatment cycle. These systems have the potential to identify individuals suffering from mental health conditions, allowing them to receive the care they need and tailor treatments to individual patients who are mostly to benefit. Additionally, unsupervised learning techniques are breaking down existing discrete diagnostic categories and highlighting the vast disease heterogeneity observed within depression diagnoses. Artificial intelligence also provides the opportunity to shift towards evidence-based treatment prescription, moving away from existing methods based on group averages. However, our analysis suggests there are several limitations currently inhibiting the progress of data-driven paradigms in care. Significantly, none of the surveyed articles demonstrate empirically improved patient outcomes over existing methods. Furthermore, greater consideration needs to be given to uncertainty quantification, model validation, constructing interdisciplinary teams of researchers, improved access to diverse data and standardised definitions within the field. Empirical validation of computer algorithms via randomised control trials which demonstrate measurable improvement to patient outcomes are the next step in progressing models to clinical implementation. [ABSTRACT FROM AUTHOR]

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition that affects social interaction and behavior. Mutations in the gene encoding chromodomain helicase DNA-binding protein 8 (CHD8) lead to autism symptoms and macrocephaly by a haploinsufficiency mechanism. However, studies of small animal models showed inconsistent findings about the mechanisms for CHD8 deficiency-mediated autism symptoms and macrocephaly. Using the nonhuman primate as a model system, we found that CRISPR/Cas9-mediated CHD8 mutations in the embryos of cynomolgus monkeys led to increased gliogenesis to cause macrocephaly in cynomolgus monkeys. Disrupting CHD8 in the fetal monkey brain prior to gliogenesis increased the number of glial cells in newborn monkeys. Moreover, knocking down CHD8 via CRISPR/Cas9 in organotypic monkey brain slices from newborn monkeys also enhanced the proliferation of glial cells. Our findings suggest that gliogenesis is critical for brain size in primates and that abnormal gliogenesis may contribute to ASD. [ABSTRACT FROM AUTHOR]

AAV-delivered CRISPR/Cas9 (AAV-CRISPR) has shown promising potentials in preclinical models to efficiently insert therapeutic gene sequences in somatic tissues. However, the AAV input doses required were prohibitively high and posed serious risk of toxicity. Here, we performed AAV-CRISPR mediated homology-independent knock-in at a new target site in mAlb 3'UTR and demonstrated that single dose of AAVs enabled long-term integration and expression of hF9 transgene in both adult and neonatal hemophilia B mice (mF9 −/−), yielding high levels of circulating human Factor IX (hFIX) and stable hemostasis restoration during entire 48-week observation period. Furthermore, we achieved hemostasis correction with a significantly lower AAV dose (2 × 109 vg/neonate and 1 × 1010 vg/adult mouse) through liver-specific gene knock-in using hyperactive hF9R338L variant. The plasma antibodies against Cas9 and AAV in the neonatal mice receiving low-dose AAV-CRISPR were negligible, which lent support to the development of AAV-CRISPR mediated somatic knock-in for treating inherited diseases. Here, the authors develop an AAV-CRISPR mediated somatic knock-in. They apply this system to restore hemostasis in neonatal hemophilia B mice and show liver-specificity of the knock-in and low serum antibody production. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of the welding process on the microstructure and mechanical properties of Au/Sn–3.0Ag–0.5Cu/Cu solder joints. In this study, the flip-chip LED chip and the substrate were connected by a heating platform, hot air reflow, and vacuum reflow soldering methods to form Au/Sn–Ag–Cu/Cu composite solder joints. Sn–3.0Ag–0.5Cu is selected as the solder. The microstructure of the solder joint interface and the inferred surface is studied to characterize the influence of different welding methods on the intermetallic compound (IMC) interface. The void ratio of the flip-chip solder layer was tested to characterize the effect of the effective connection area between the chip and the solder joint on the shear strength. The experimental results show that the void ratio of the solder joints welded by the heating platform is as high as 26%, the IMC interface thickness is higher, and the diffusion coefficient of the solder is the lowest. The void distribution of hot air reflow soldering joints is relatively uniform, and there is less solder residue on the fractured surface. Vacuum reflow soldering has the lowest void rate in the solder joints, and the solder joints have flat cross sections with almost no solder residues. The fracture occurs at the lower layer of solder. Considering comprehensively, when the soldering method is vacuum reflow, the IMC layer of the flip-chip solder joint is the thinnest, and the diffusion coefficient of the solder is the highest. There are almost no voids in the solder layer, and the mechanical properties of the solder joint are the best. At this time, the photo-thermoelectric parameters of the filament are the best, and the performance is the most stable and reliable. [ABSTRACT FROM AUTHOR]

A UVC-LED is a deep ultraviolet LED with a wavelength of 200–280 nm, which has a wide range of applications in disinfection, water purification and other fields. However, UVC-LED chips have limitations of high heat and poor heat dissipation, so it is necessary to test and analyze the thermal and optical properties of UVC-LEDs. This paper studies the photothermal characteristics of a UVC-LED under different driving currents. By measuring and analyzing the radiation flux, radiation intensity, junction temperature and thermal resistance of the UVC-LED under different driving currents, it is found that the junction temperature of the UVC-LED under the transient and steady state increases with the increase in the driving current, while the thermal resistance decreases. The radiation flux and intensity of the UVC-LED increase with the increase in driving current. The peak wavelength appears as a redshift with the increase in current, and the half-wave width also increases with the increase in current. [ABSTRACT FROM AUTHOR]

This article focuses on the study of voids in the solder joint interface of flip-chip LEDs. Additional flux is added to the solder paste to reduce the frequency of voids, and the mechanical properties of the solder joints are compared and analyzed. Two kinds of fluxes (NC559-TPF, TSF-6516) are selected. They are used in two kinds of solder pastes (lead and lead-free solder paste). The amount of flux added is 0 mL, 0.4 mL, and 0.8 mL. The other preparation conditions for all combinations are the same and are within the recommended scope of the manufacturer's documentation. X-rays are used to detect and analyze the distribution and quantity of voids in the solder layer. A push–pull tester is used to analyze and evaluate the mechanical strength of the solder joints. A scanning electron microscope was used to observe the microscopic morphology of the cross-section of the solder joint and the fracture morphology of the interface after the shear test. It was found that adding a proper amount of high-activity flux to the solder paste can reduce the frequency of voids and improve the mechanical reliability of the solder joints. Finally, we tested the thermal performance of the flip-chip LED filament for verification. [ABSTRACT FROM AUTHOR]

In the actual production process, soldering is a key step in the flip-chip packaging process. The reliability of the interconnection interface of flip-chip LED chips is considered to be one of the most important reliability issues. This paper studies the influence of different soldering temperatures on the microstructure and shear behavior of the Au/Sn-3.0Ag-0.5Cu/Cu solder joints of flip-chip LED chips. The lead-free solder Sn-3.0Ag-0.5Cu was selected as the solder. The microstructure of the intermetallic compound (IMC) interface and the inferred surface of the solder joint is observed, and the microstructure evolution of the solder joint is analyzed. The void ratio of the solder joints at 250°C, 260°C, 270°C, 280°C, and 290°C soldering temperature was tested to characterize the influence of the contact area between the chip and the solder joint on the shear stress. In addition, the solder joints were aged for 1000 hours in an environment with a relative humidity of 85°C/85%, and a shear test was performed to evaluate the influence of the interface reaction on the mechanical reliability of the solder joints during the isothermal aging process. The research show that when the soldering temperature is 270°C, the Au on the bottom of the chip, and the solder and Cu on the substrate have fully reacted, and the solder joints have high shear resistance. The shear strength of the aging solder joints increases first and then decreases, because the high temperature repairs the defects in the solder layer caused by the low soldering temperature to a certain extent. With the extension of aging, cracks and voids gradually appear at the fracture interface, and the effective contact area decreases. The shear strength of the solder joint decreases, and the fracture mode becomes brittle. [ABSTRACT FROM AUTHOR]

The epigenetic mechanisms coordinating the maintenance of adult cellular lineages and the inhibition of alternative cell fates remain poorly understood. Here we show that targeted ablation of the histone chaperone HIRA in myogenic cells leads to extensive transcriptional modifications, consistent with a role in maintaining skeletal muscle cellular identity. We demonstrate that conditional ablation of HIRA in muscle stem cells of adult mice compromises their capacity to regenerate and self-renew, leading to tissue repair failure. Chromatin analysis of Hira-deficient cells show a significant reduction of histone variant H3.3 deposition and H3K27ac modification at regulatory regions of muscle genes. Additionally, we find that genes from alternative lineages are ectopically expressed in Hira-mutant cells via MLL1/MLL2-mediated increase of H3K4me3 mark at silent promoter regions. Therefore, we conclude that HIRA sustains the chromatin landscape governing muscle cell lineage identity via incorporation of H3.3 at muscle gene regulatory regions, while preventing the expression of alternative lineage genes. The epigenetic mechanisms coordinating the maintenance of adult cellular lineages remain poorly understood. Here the authors demonstrate that HIRA, a H3.3 histone chaperone, establishes the chromatin landscape required for skeletal muscle cell identity. [ABSTRACT FROM AUTHOR]

The basis for the formation of spherical edge burrs during servo valve spool shoulder grinding and a method for eliminating these burrs were investigated. Based on the results of this investigation, a grinding and synchronous deburring device was designed. A geometric model of single abrasive grains was established and the formation mechanism of the valve spool edge burrs was evaluated. Subsequently, the deburring process was analyzed via dynamic simulations, and based on the results, the aforementioned device was designed for mounting on an S20 precision cylindrical grinder. The correctness of the simulation and the feasibility of the device were verified via experiments. The experimentally observed burr shape and size corresponded closely to the simulated features. Moreover, the test device was effective in removing the edge burrs of the valve spool, as evidenced by the lack of sharp edge burrs. Hence, this device could be helpful in grinding the valve spool shoulder for significant improvement in the processing quality and efficiency. [ABSTRACT FROM AUTHOR]

Novel electronic donor with polycyclic structure based on coumarin was designed and prepared. Pyrrolidine acting as an isolated group was introduced to the donor by the Buchwald-Hartwig amination reaction. Such a novel electronic donor demonstrated great electron-donating capability and an excellent isolation effect. Both chromophores exhibited a D-π-A-π-A molecular structure. Such a structure has great advantages in energy matching, dipole interaction, and electron transfer, compared to the single D-π-A structure. The chemical structures of novel chromophores based on this donor were characterized by 1H nuclear magnetic resonance spectroscopy, 13C nuclear magnetic resonance spectroscopy, and mass spectrometry. The largest electro-optic coefficients are approximately 31.2 and 42.6 pm/V for chromophores NLO-C and NLO-P, respectively, at 1310 nm; otherwise, both chromophores NLO-C and NLO-P exhibit high thermal decomposition temperatures, i.e., 276 and 237 °C, respectively. [ABSTRACT FROM AUTHOR]

Patterns are used as a fundamental means to analyse data in many text mining applications. Many efficient techniques have been developed to discover patterns. However, the excessive number of discovered patterns and lack of grounded (e.g. a priori defined) semantics have made it difficult for a user to interpret and explore the patterns. An insight into the meanings of the patterns can benefit users in the process of exploring them. In this regard, this paper presents a model to automatically interpret patterns by achieving two goals: (1) providing the meanings of patterns in terms of ontology concepts and (2) providing a new method for generating and extracting features from an ontology to describe the relevant information more effectively. Taking advantage of a domain ontology and a set of relevant statistics (e.g. term frequency in a document, inverse term frequency in a domain ontology, etc.), our proposed model can give an insight into the hidden meanings of the patterns. The model is evaluated by comparing it with different baseline models on three standard datasets. The results show that the performance of the proposed model is significantly better than baseline models. [ABSTRACT FROM AUTHOR]

GaN thin films and multi-quantum wells (MQWs) were grown on the c-axis patterned sapphire substrates and c-axis flat sapphire substrates by metal organic chemical vapor deposition, respectively. The surface morphology of patterned sapphire substrate and flat sapphire substrate were measured by scanning electron microscopy. The crystal structure of GaN thin films and MQWs were measured by X-ray. The optical performance of MQWs was measured by photoluminescence spectra. The residual stress of GaN thin films was studied. GaN thin films on patterned sapphire substrate has a better crystalline quality in the [102] direction than that on flat sapphire substrate. The residual stress in MQWs on PSS is δ = 1.10 GPa, δ = 0.13 GPa, while the residual stress of films on FSS is δ = 0.83 GPa, δ = 0.10 GPa. It is found that the wavelength becomes shorter and the emission intensity becomes stronger on patterned sapphire substrate. [ABSTRACT FROM AUTHOR]

The catalytic behavior of ultra-low-gold-loaded Au/CeO during CO oxidation was studied using HRTEM, TGA, in-situ FTIR, CO-TPD, O-TPD, and O-TPO. Herein, water, which facilitates CO oxidation, is present on the catalyst rather than obtained from the reactant gas. The experimental results show that the presence of water on the catalyst enhances the adsorption and activation of O to produce O on the catalyst surface, resulting in excellent catalytic activity. Different reaction pathways for CO oxidation over Au/CeO may be present; however, the dominant pathway is influenced by the species on the catalyst surface. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

This paper provides a review of paleoclimate modeling activities in China. Rather than attempt to cover all topics, we have chosen a few climatic intervals and events judged to be particularly informative to the international community. In historical climate simulations, changes in solar radiation and volcanic activity explain most parts of reconstructions over the last millennium prior to the industrial era, while atmospheric greenhouse gas concentrations play the most important role in the 20th century warming over China. There is a considerable model-data mismatch in the annual and boreal winter temperature change over China during the mid-Holocene [6000 years before present (ka BP)], while coupled models with an interactive ocean generally perform better than atmospheric models. For the Last Glacial Maximum (21 ka BP), climate models successfully reproduce the surface cooling trend over China but fail to reproduce its magnitude, with a better performance for coupled models. At that time, reconstructed vegetation and western Pacific sea surface temperatures could have significantly affected the East Asian climate, and environmental conditions on the Qinghai-Tibetan Plateau were most likely very different to the present day. During the late Marine Isotope Stage 3 (30-40 ka BP), orbital forcing and Northern Hemisphere glaciation, as well as vegetation change in China, were likely responsible for East Asian climate change. On the tectonic scale, the Qinghai-Tibetan Plateau uplift, the Tethys Sea retreat, and the South China Sea expansion played important roles in the formation of the East Asian monsoon-dominant environment pattern during the late Cenozoic. [ABSTRACT FROM AUTHOR]

The NOAA daily outgoing longwave radiation (OLR) and the Global Precipitation Climatology Project (GPCP) daily precipitation data are used to study the variation of dominant convection modes and their relationships over Asia, the Indian Ocean, and the western Pacific Ocean during the summers from 1997 to 2004. Major findings are as follows: (1) Regression analysis with the OLR indicates the convective variations over Asian monsoon region are more closely associated with the convective activities over the western subtropical Pacific (WSP) than with those over the northern tropical Indian Ocean (NTIO). (2) The EOF analysis of OLR indicates the first mode (EOF1) exhibits the out-of-phase variations between eastern China and India, and between eastern China and the WSP. The OLR EOF1 primarily exhibits seasonal and even longer-term variations. (3) The OLR EOF2 mostly displays in-phase convective variations over India, the Bay of Bengal, and southeastern China. A wavelet analysis reveals intraseasonal variation (ISV) features in 2000, 2001, 2002, and 2004. However, the effective ISV does not take place in every year and it seems to occur only when the centers of an east-west oriented dipole reach enough intensity over the tropical Indian and western Pacific Oceans. (4) The spatial patterns of OLR EOF3 are more complicated than those of EOF1 and EOF2, and an effective ISV is noted from 1999 to 2004. The OLR EOF3 implies there is added complexity of the OLR pattern when the effective ISV occurs. (5) The correlation analysis suggests the precipitation over India is more closely associated with the ISV, seasonal variations, and even longer-term variations than precipitation occurring over eastern China. [ABSTRACT FROM AUTHOR]

Intercropping of upland rice with short-duration grain legumes has major advantages in increasing crop yields and soil productivity. However, the contribution of arbuscular mycorrhizas, the common mutualistic symbiosis between most crops and mycorrhizal fungi, is not fully understood in intercropping systems. We assayed the contribution of inoculation of the arbuscular mycorrhizal fungus (AMF) Glomus caledonium on nutrient acquisition and biomass yield. Using the method of plastic film and nylon net partition and tracing 15N transferred between the intercropped upland rice ( Oryza sativa ssp. Japonica Nipponbare) and mung bean ( Vigna radiata L. Chuanyuan), we compared the intercropping, with separation of the whole root systems by a plastic film, with and without a barrier of nylon net to allow penetration of the fungal hyphae. Intercropping significantly improved the formation of arbuscular mycorrhizas, particularly in the upland rice roots. The improved formation of mycorrhizas by the intercropping increased total P uptake by 57% in rice, total P and N acquisition by 65% and 64% respectively in mung bean, and nodulation by 54% in mung bean. The percentage of total 15N transfer from mung bean to rice leaves was increased from 5.4% to 15.7% by inoculation with AMF. In contrast, there was only 2.7% of 15N transfer from rice to mung bean and no AMF effect on N transfer. It is concluded that cereal and legume crop intercropping increase mycorrhiza formation, which in turn improves nodulation, N and P acquisition and N transfer in the legumes. [ABSTRACT FROM AUTHOR]

In order to investigate the conversion of kinetic energy from a synoptic scale disturbance (SSD; period⩽seven days) to a low-frequency fluctuation (LFF; period>seven days), the budget equation of the LFF kinetic energy is derived. The energy conversion is then calculated and analyzed for the summers of 1997 and 1999. The results show that the energy conversion from the SSD to the LFF is obviously enhanced in the middle and lower troposphere during the heavy rainfall, suggesting this to be one of mechanisms inducing the heavy rainfall, although the local LFF kinetic energy may not be enhanced. [ABSTRACT FROM AUTHOR]