Soft-Defined Heterogeneous Vehicular Network: Architecture and Challenges

Heterogeneous Vehicular NETworks (HetVNETs) can meet various quality-of-service (QoS) requirements for intelligent transport system (ITS) services by integrating different access networks coherently. However, the current network architecture for HetVNET cannot efficiently deal with the increasing demands of rapidly changing network landscape. Thanks to the centralization and flexibility of the cloud radio access network (Cloud-RAN), soft-defined networking (SDN) can conveniently be applied to support the dynamic nature of future HetVNET functions and various applications while reducing the operating costs. In this paper, we first propose the multi-layer Cloud RAN architecture for implementing the new network, where the multi-domain resources can be exploited as needed for vehicle users. Then, the high-level design of soft-defined HetVNET is presented in detail. Finally, we briefly discuss key challenges and solutions for this new network, corroborating its feasibility in the emerging fifth-generation (5G) era

Effects of Graphite Additions on Microstructures and Wear Resistance of Fe-Cr-C-Nb Hardfacing Alloys

Hardfacing alloys with different carbon contents by changing graphite additions in flux-cored wires were prepared on a surface of steel C45E4 (ISO 683) using open-arc overlaying. Testing was conducted using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), a Rockwell hardness tester and an abrasion tester to study the effect of variation of graphite additions on the microstructures, hardness and abrasive resistance of the hardfacing alloys. The results show that the microstructures of the hardfacing alloys consisted of ferrite, martensite, retained austenite, independent austenite and NbC particles. Firstly, as graphite additions increased, the carbon contents gradually increased and the microstructures of the hardfacing alloys changed from ferrite plus NbC particles to martensite with retained austenite and larger NbC particles, which was accompanied by hardness increasing and better abrasive resistance. And then the hardfacing layer alloy best performance was obtained as graphite addition was 60 g. The highest hardness was 61.8 HRC and the wear resistance was nearly four times as high as that of the base metal. But excessive graphite additions resulted in some independent austenite present in the microstructures of the hardfacing alloys together with martensite plus retained austenite and NbC particles, which deteriorated the performance of the hardfacing alloys

Binarized Neural Architecture Search

Neural architecture search (NAS) can have a significant impact in computer vision by automatically designing optimal neural network architectures for various tasks. A variant, binarized neural architecture search (BNAS), with a search space of binarized convolutions, can produce extremely compressed models. Unfortunately, this area remains largely unexplored. BNAS is more challenging than NAS due to the learning inefficiency caused by optimization requirements and the huge architecture space. To address these issues, we introduce channel sampling and operation space reduction into a differentiable NAS to significantly reduce the cost of searching. This is accomplished through a performance-based strategy used to abandon less potential operations. Two optimization methods for binarized neural networks are used to validate the effectiveness of our BNAS. Extensive experiments demonstrate that the proposed BNAS achieves a performance comparable to NAS on both CIFAR and ImageNet databases. An accuracy of $96.53\%$ vs. $97.22\%$ is achieved on the CIFAR-10 dataset, but with a significantly compressed model, and a $40\%$ faster search than the state-of-the-art PC-DARTS

Clinical research on progress of antinuclear antibody in rheumatoid arthritis

Rheumatoid arthritis (RA) is a common chronic, systemic autoimmune disease characterized by erosive arthritis, with a global prevalence of 0.25% to 1.00%, which may ultimately lead to joint deformity and loss of function. Antinuclear antibody (ANA) refers to auto-antibodies that target various components of eukaryotic cells. Although ANA may be frequently detected in RA patients, with a positive rate of 30% to 60%, the significance of ANA in the diagnosis and treatment of RA remains unclear. Nuclear patterns in RA population are dominated by speckled and homogeneous patterns, mainly at low titres. The detection rate of extractable nuclear antibodies is usually lower than that of ANA. The serum levels of rheumatoid factor and anti-cyclic citrullinated peptide antibody in ANA-positive RA patients are much higher than ANA-negative ones, and joint erosion of ANA-positive RA patients had more severe joint erosion on imaging as well. Therefore, ANA is a potential predictor of severe joint injury. ANA-positive RA patients are more likely to have extra-articular manifestations [such as subcutaneous nodules(82% vs 46%), ocular lesions(38% vs 6%), and infections(38% vs 12%)].In terms of RA comorbidities, compared to the ANA negative group, the ANA positive group had higher levels of moderate and severe anemia (16.04% vs 6.9%; 6.6% vs 0.07%), Sjogren's syndrome (19.5% vs 4.1%), and vasculitis (29% vs 7%). In addition, ANA positivity is an independent risk factor for elderly RA patients with carotid intimal thickening (HR=4.089) and adverse pregnancy outcomes in female RA (OR=3.268, P=0.045), respectively. Attention should be paid to high-titre ANA-positive RA patients for preventive measures. In terms of treatment, RA patients who are ANA-positive when given tumour necrosis factor-α inhibitor (TNFi) treatment got much poorer therapeutic response than ANA-negative ones, especially those with high titres were more prone to generating anti-drug antibodies. Increase of ANA titer induced by TNFi is associated with no response to TNFi treatment, thus monitoring the change of ANA may predict the long-term efficacy of TNFi. The most common adverse event of TNFi is drug-induced lupus. Although it has been confirmed that the induction of anti-double-stranded DNA antibodies is associated with poor efficacy of TNFi, large-scale studies are still needed to confirm the correlation between the increase of ANA titer or ocurence of dsDNA antibody and the induction of drug-induced lupus. In conclusion, this paper reviews the research progress on ANA characteristics in RA population, clinical manifestations of ANA-positive RA, and the association between ANA and TNFi prognosis. The potential of ANA as a new biomarker of RA needs to be further studied

Effects of straw returning combined with earthworm addition on nitrification and ammonia oxidizers in paddy soil

IntroductionSoil ammonia oxidation, which acts as the first and rate-limiting step of nitrification, is driven by ammonia-oxidizing bacteria (AOB), ammonia-oxidizing archaea (AOA) and complete ammonia oxidizer (comammox, amoA gene of clade-A and clade-B). Straw returning, widely used ecological technology in China, is an effective measure for promoting straw decomposition and soil nutrient cycling when combined with earthworm addition. However, the effects of straw returning combined with earthworm addition on soil ammonia oxidizers remain poorly understood.MethodsA 2-year plot experiment was conducted with 5 treatments: no fertilizer (CK); regular fertilization (RT); straw returning (SR); earthworm addition (W); straw returning + earthworm addition (SRW). The AOA, AOB, comammox clade-A and clade-B community microbial diversities and structures were investigated by high-throughput sequencing.ResultsThe results showed that (1) compared to RT treatment, W, SR, and SRW treatments all significantly increased the richness of AOA and comammox clade-A and clade-B (p < 0.05), and the richness of AOB was only significantly promoted by SRW treatment (p < 0.05). However, only SRW had a higher comammox clade-B diversity index than RT. (2) The ammonia oxidizer community structures were altered by both straw returning and earthworm addition. Soil NH4+-N was the critical environmental driver for altering the ammonia oxidizer community structure. (3) Compared with RT treatment, the soil potential nitrification rate (PNR) of W and SRW treatments increased by 1.19 and 1.20 times, respectively. The PNR was significantly positively correlated with AOB abundance (path coefficient = 0.712, p < 0.05) and negatively correlated with clade-B abundance (path coefficient = −0.106, p < 0.05).DiscussionThis study provides scientific support for the application of straw returning combined with earthworm addition to improve soil nitrification with respect to soil ammonia-oxidizing microorganisms

Long-term effects of straw and straw-derived biochar on soil aggregation and fungal community in a rice–wheat rotation system

Background Soil aggregation is fundamental for soil functioning and agricultural productivity. Aggregate formation depends on microbial activity influencing the production of exudates and hyphae, which in turn act as binding materials. Fungi are also important for improving soil quality and promoting plant growth in a symbiotic manner. There is a scarcity of findings comparing the long-term impacts of different yearly double-crop straw return modes (e.g., straw return to the field and straw-derived biochar return to the field) on soil aggregation and fungal community structure in rice–wheat rotation systems. Methods The effects of 6-year continuous straw and straw-derived biochar amendment on soil physicochemical properties and the fungal community were evaluated in an intensively managed crop rotation system (rice–wheat). Soil samples of different aggregates (macroaggregates, microaggregates, and silt clay) from four different fertilization regimes (control, CK; traditional inorganic fertilization, CF; straw returned to field, CS; straw-derived biochar addition, CB) were obtained, and Illumina MiSeq sequencing analysis of the fungal internal transcribed spacer gene was performed. Results Compared to CF, CS and CB enhanced soil organic carbon, total nitrogen, and aggregation in 0–20 and 20–40 cm soil, with CB exhibiting a stronger effect. Additionally, agrowaste addition increased the mean weight diameter and the geometric diameter and decreased the fractal dimension (p < 0.05). Principal coordinates analysis indicated that fertilization management affected fungal community structure and aggregation distribution. In addition, CS increased fungal community richness and diversity, compared to CK, CB decreased these aspects. Ascomycota, unclassified_k_Fungi, and Basidiomycota were the dominant phyla in all soil samples. At the genus level, CB clearly increased fungi decomposing biosolids (Articulospora in macroaggregates in 0–20 cm soil and Neurospora in macroaggregates in 20–40 cm soil); decreased pathogenic fungi (Monographella in macroaggregates and Gibberella in microaggregates in 0–20 cm soil) and CO2-emission-related fungi (Pyrenochaetopsis in microaggregates and silt clay in 0–40 cm soil) (p < 0.05). Straw and biochar with inorganic fertilizer counteracted some of the adverse effects of the inorganic fertilizer with biochar showing better effects than straw