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The issue of food safety has received significant attention in recent years. Heavy metal ions in food can accumulate in living organisms and significantly threaten human health. Therefore, it is crucial to detect heavy metal ions. Conventional instrumental analysis methods have high accuracy, but the disadvantage is the high cost and the complexity of the operation process, so it is very urgent to establish a low-cost, rapid, and continuous detection method for heavy metal ions. Field effect transistor (FET) biosensors are one of the most promising detection tools for heavy metal ion detection due to demonstrated advantages of rapidity, accuracy, and continuity in hazard detection. This review first introduces the structure and principle of graphene FETs in detail, then lists some examples of graphene FETs for detecting common heavy metal ions, and analyzes their advantages and disadvantages in depth. Finally, the development direction of graphene FET biosensors in heavy metal ion detection highlighted in this paper. [ABSTRACT FROM AUTHOR]

The outbreak of the 2022 Russia-Ukraine conflict exacerbated the natural gas supply shortage in European countries. European countries restarted coal-fired power plants to maintain economic and social operations. The uneven distribution of coal resources in the world makes coal international trade inevitable. The intricate trade relations between trading countries have formed a coal trade network. When a country's coal exports are limited due to geopolitical factors, it will cause coal supply risks. The risk will spread to more countries along the trade network, eventually leading to the collapse of the trade network. This paper builds a crisis propagation model of the coal supply under the Russia-Ukraine conflict using the cascading failure model. The results showed that the Czech Republic, Ireland, Portugal, and Bulgaria become abnormal as the proportion of coal exports β increases. When the Russian Federation reduced its coal exports by 80% and countries maintained only 10% coal exports against crisis, 23 European countries were the worst. Iceland, Ireland, Turkey and other countries were spread by the indirect risk and became abnormal countries. The Czech Republic and Bulgaria were spread by multiple risk and became abnormal countries. [ABSTRACT FROM AUTHOR]

Objective: To compare examination time and image quality between artificial intelligence (AI)–assisted compressed sensing (ACS) technique and parallel imaging (PI) technique in MRI of patients with nasopharyngeal carcinoma (NPC). Methods: Sixty-six patients with pathologically confirmed NPC underwent nasopharynx and neck examination using a 3.0-T MRI system. Transverse T2-weighted fast spin-echo (FSE) sequence, transverse T1-weighted FSE sequence, post-contrast transverse T1-weighted FSE sequence, and post-contrast coronal T1-weighted FSE were obtained by both ACS and PI techniques, respectively. The signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and duration of scanning of both sets of images analyzed by ACS and PI techniques were compared. The images from the ACS and PI techniques were scored for lesion detection, margin sharpness of lesions, artifacts, and overall image quality using the 5-point Likert scale. Results: The examination time with ACS technique was significantly shorter than that with PI technique (p < 0.0001). The comparison of SNR and CNR showed that ACS technique was significantly superior with PI technique (p < 0.005). Qualitative image analysis showed that the scores of lesion detection, margin sharpness of lesions, artifacts, and overall image quality were higher in the ACS sequences than those in the PI sequences (p < 0.0001). Inter-observer agreement was evaluated for all qualitative indicators for each method, in which the results showed satisfactory-to-excellent agreement (p < 0.0001). Conclusion: Compared with the PI technique, the ACS technique for MR examination of NPC can not only shorten scanning time but also improve image quality. Clinical relevance statement: The artificial intelligence (AI)–assisted compressed sensing (ACS) technique shortens examination time for patients with nasopharyngeal carcinoma, while improving the image quality and examination success rate, which will benefit more patients. Key Points: • Compared with the parallel imaging (PI) technique, the artificial intelligence (AI)–assisted compressed sensing (ACS) technique not only reduced examination time, but also improved image quality. • Artificial intelligence (AI)–assisted compressed sensing (ACS) pulls the state-of-the-art deep learning technique into the reconstruction procedure and helps find an optimal balance of imaging speed and image quality. [ABSTRACT FROM AUTHOR]

Autonomous driving has been widely applied in commercial and industrial applications, along with the upgrade of environmental awareness systems. Tasks such as path planning, trajectory tracking, and obstacle avoidance are strongly dependent on the ability to perform real-time object detection and position regression. Among the most commonly used sensors, camera provides dense semantic information but lacks accurate distance information to the target, while LiDAR provides accurate depth information but with sparse resolution. In this paper, a LiDAR-camera-based fusion algorithm is proposed to improve the above-mentioned trade-off problems by constructing a Siamese network for object detection. Raw point clouds are converted to camera planes to obtain a 2D depth image. By designing a cross feature fusion block to connect the depth and RGB processing branches, the feature-layer fusion strategy is applied to integrate multi-modality data. The proposed fusion algorithm is evaluated on the KITTI dataset. Experimental results demonstrate that our algorithm has superior performance and real-time efficiency. Remarkably, it outperforms other state-of-the-art algorithms at the most important moderate level and achieves excellent performance at the easy and hard levels. [ABSTRACT FROM AUTHOR]

In this study, a simple label-free biosensor for Brucella was constructed, which based on the screen-printed carbon electrode (SPCE) modified by Recombinant protein G/gold nanoparticles/graphene oxide (RpG/Au/GO). The impedance responses of the proposed biosensor were measured by electrochemical AC impedance method in Brucella antigen gradient concentration solutions. The results showed that the linear range of this biosensor was from 1.6 × 102 CFU/mL to 1.6 × 108 CFU/mL with the minimum detection limit of 3.2 × 102 CFU/mL (S/N = 3). Moreover, the biosensor for Brucella detection possessed acceptable reproducibility with a relative standard deviation of 5.15% and acceptable stability with a relative standard deviation of 4.68%. The spiked recovery rate in actual pasteurized milk samples was more than 92%. Therefore, the developed biosensor exhibits excellent prospects in the selective quantification detection of Brucella abortus. [ABSTRACT FROM AUTHOR]

To effectively cut off the transmission of Brucella to humans through milk, a novel biosensor for detection of Brucella was constructed using cysteamine functionalized nanogold (Cys-Au) and 4-Mercaptobenzoic acid (4-MBA) modified gold electrode as the platform. The morphology of the prepared nanomaterials was characterized by laser particle sizer, XPS and SEM, and the results showed the 4-MBA film was modified on the gold electrode surface, and the diameter of successfully prepared nanogold and Cys-Au are about 55 and 65 nm, respectively. The electrochemical performance of the biosensor was tested in Brucella antigen solution by square wave voltammetry (SWV). The results showed the reproducibility and stability of the biosensor were good, the spiked recovery in milk was in the range of 95.12–105.27%, and the minimum detection limit (S/N = 3) was 5.12 × 102 cfu/mL with a linear range from 1.6 × 102 to 1.6 × 108 cfu/mL. In addition, the minimum detection limit was reduced from 5.12 × 102 cfu/mL to 7.0 × 101 cfu/mL after processing the SWV data by second-order derivative transformation, which showed Second-order derivative transformation is very helpful to further optimize the performance of the sensor. Compared with the previously reported test methods, the prepared biosensors have a wider linear range and lower limit of detection (LOD). Therefore, the constructed biosensor can be used as a promising tool for the trace detection of Brucella in milk samples. [ABSTRACT FROM AUTHOR]

Under environmental policies and consumers' green preferences, firms are facing the problem of how to improve the efficiency of emission reduction (ER) and increase profit. In this paper, we construct an analytical framework that includes a manufacturer and a retailer to explore the value of cooperative ER under the carbon cap-and-trade mechanism (CCTM). The manufacturer invests in green technologies to reduce emissions, and the retailer can choose whether to implement green marketing. We find that cooperative ER can increase the manufacturer's ER level and the profit of the manufacturer and the retailer. In the retailer-led situation, the manufacturer's ER level and the retailer's marketing level are both higher than in the manufacturer-led situation. Moreover, the economic performance of the supply chain (SC) is better. Furthermore, when consumers have a strong green preference, the value of cooperative ER is greater; in addition, the advantage of the retailer-led situation is more obvious. Our work enriches the ER theory and provides guidance for firms to reduce emissions. [ABSTRACT FROM AUTHOR]

The quantum Cramér–Rao bound sets a fundamental limit on the accuracy of unbiased parameter estimation in quantum systems, relating the uncertainty in determining a parameter to the inverse of the quantum Fisher information. We experimentally demonstrate near saturation of the quantum Cramér–Rao bound in the phase estimation of a solid-state spin system, provided by a nitrogen-vacancy center in diamond. This is achieved by comparing the experimental uncertainty in phase estimation with an independent measurement of the related quantum Fisher information. The latter is independently extracted from coherent dynamical responses of the system under weak parametric modulations, without performing any quantum-state tomography. While optimal parameter estimation has already been observed for quantum devices involving a limited number of degrees of freedom, our method offers a versatile and powerful experimental tool to explore the Cramér–Rao bound and the quantum Fisher information in systems of higher complexity, as relevant for quantum technologies. [ABSTRACT FROM AUTHOR]

The emergence of multidrug resistance bacteria poses a great health theat. Therefore, it is a crucial demand to obtain new antibacterial drugs. Antimicrobial peptides (AMPs) have the characteristics of wide antimicrobial spectrum and lower drug resistance, hence, it is hopeful to substitute for classical antibiotics. In this study, two classic methods, comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA), were used to analyze the structural feature of AMPs against Staphylococcus aureus or Escherichia coli, respectively. Subsequently, the models established by three-dimensional quantitative structure–activity relationships (3D-QSAR) (for S. aureus, CoMFA: Q2 = 0.512, R2 = 0.943, F = 59.916; CoMSIA: Q2 = 0.645, R2 = 0.993, F = 339.242; for E. Coli, CoMFA: Q2 = 0.507, R2 = 0.913, F = 66.862; CoMSIA: Q2 = 0.573, R2 = 0.966, F = 96.84) have good predictability and stability was constructed. Seven novel small AMPs were designed and synthesized based on the theoretical model. The novel AMPs showed potent antibacterial activity against S. aureus and E. coli while causing low host toxicity. This study provides a potential therapeutic option using 3D-QSAR models guiding the design and modification of novel AMPs, to address the prevalent infections caused by MDR bacterial. [ABSTRACT FROM AUTHOR]

Herein, the influence of Ti additive on the formation of intermetallic compounds (IMC) in a SAC/Cu-Ti soldered joint and corresponding mechanical properties are systematically investigated. The Ti-to-Cu ratio under bump metallization (UBM) is adjusted by tuning the target current during magnetron sputtering. Interestingly, the needle-like IMC, which is different from the traditional scallop-like IMC, is formed in the SAC/Cu-Ti soldered joint after reflow. The growth of Cu3Sn and Kirkendall voids is significantly inhibited after thermal aging in the SAC/Cu-Ti soldered joint. Overall, the segregation of Ti at grain boundaries forms a titanium-rich layer. Also, the Ti-rich layer acts as a diffusion barrier layer and hinders the diffusion of Cu into IMC. The shear strength test results show that SAC/Cu-Ti has much stronger strength than SAC/Cu both before and after thermal aging. These results confirm that Cu-Ti UBM is beneficial to the improvement of welding reliability. [ABSTRACT FROM AUTHOR]

Interferon (IFN) responses are central to host defense against coronavirus and other virus infections. Manganese (Mn) is capable of inducing IFN production, but its applications are limited by nonspecific distributions and neurotoxicity. Here, we exploit chemical engineering strategy to fabricate a nanodepot of manganese (nanoMn) based on Mn2+. Compared with free Mn2+, nanoMn enhances cellular uptake and persistent release of Mn2+ in a pH-sensitive manner, thus strengthening IFN response and eliciting broad-spectrum antiviral effects in vitro and in vivo. Preferentially phagocytosed by macrophages, nanoMn promotes M1 macrophage polarization and recruits monocytes into inflammatory foci, eventually augmenting antiviral immunity and ameliorating coronavirus-induced tissue damage. Besides, nanoMn can also potentiate the development of virus-specific memory T cells and host adaptive immunity through facilitating antigen presentation, suggesting its potential as a vaccine adjuvant. Pharmacokinetic and safety evaluations uncover that nanoMn treatment hardly induces neuroinflammation through limiting neuronal accumulation of manganese. Therefore, nanoMn offers a simple, safe, and robust nanoparticle-based strategy against coronavirus. [ABSTRACT FROM AUTHOR]

CBX8 is the core component of the PCG family protein PRC1 complex. It is overexpressed in many solid tumors and plays an important role in the prognosis and biological behaviors of tumors such as occurrence, development, invasion, and metastasis. However, exploration of the role and molecular mechanism of CBX8 in tumors is still in its infancy. Our study found that the down-regulation of CBX8 expression by RNA interference induced differential expression of several microRNAs in human colon cancer cells. The 5 most differentially expressed miRNA precursors (pre-miRNA) (hsa-miR-363-3p, hsa-miR-378a-3p, hsa-miR-371b-3p, hsa-miR-361-3p, and hsa-miR-576-3p) share a common motif sequence: ARAAAKUGCMC. We selected miR-378a-3p and further revealed that the negative regulation of miRNA expression by CBX8 mainly occurs in the processing of pre-miRNA to mature miRNA. CBX8 uses its own RNA-binding domain to interact with pre-miRNA, and is dependent on its own nuclear localization characteristics to limit nucleoplasmic transport of pre-miRNA. Changing the characteristic sequence of pre-miRNA or mutating the RNA-binding domain and nuclear localization signal of CBX8 can effectively weaken the regulation of miR-378a-3p expression by CBX8. However, our experimental results showed that miR-378a-3p inhibited the malignant expression of human colon cancer cells by targeting PDIA4, resulting in increased activity of caspases-3 and -7. In summary, our study suggests that CBX8 acts as an independent RNA-binding protein to regulate miRNA expression. Simultaneously, this study shows the correlation between the CBX8/miR-378a-3p/PDIA4 pathway and the malignant biological properties of colorectal cancer, suggesting this proposed pathway as a possible therapeutic target for human cancers. [ABSTRACT FROM AUTHOR]

Colla corii asini (CCA) is a widely used animal-derived traditional medicine and nutritional supplement in China that has a variety of bioactive effects, especially anti-anaemic effects. To date, the effective substances in CCA are still unclear, thus limiting the evaluation of the quality and consistency of CCA. In this study, a microcalorimetry-based bioassay method was established to assess the quality of CCA by investigating its effects on the growth and metabolism of Escherichia coli, and ten biothermodynamic parameters were employed to characterize the biothermal changes. A principal component analysis (PCA) of these parameters showed that CCA significantly promotes the heat production of E. coli compared to that in the control group, and CCA showed an obvious dose–effect relationship from 0.625 to 20 mg mL−1. Then, the effects of 12 batches of CCA from three different manufacturers were studied at a concentration of 5 mg mL−1, which had a good effect and showed good intraday and daytime reproducibility. The results revealed distinctive characteristics among different manufacturers and good consistency within the same manufacturer according to the scores of the first principal component. In summary, the method based on microcalorimetric has good prospects in the evaluation of the quality of CCA. [ABSTRACT FROM AUTHOR]

The application of the relay networks enlarges the communication area and improves the transmission. However, the price is the increasing system complexity, which makes the performance analysis of the corresponding channel a more challenging task. To this end, we develop the probability density function (PDF) of the composite cascade channel, and later analyze the outage probability (OP), the bit error rate (BER), and the ergodic capacity over this channel. Firstly, the exact PDF of the small-scale cascade channel, which is combined by several independent and identically distributed (i.i.d.) Rayleigh/Nakagami-m channels, is derived. Then, considering the large-scale and the lognormal distributed shadow, the PDF of the composite cascade channel, following the OP, the BER, and the ergodic capacity performance under the optimal selection combining (OSC) and the maximal ratio combining (MRC) schemes are also deduced. Furthermore, in order to obtain the asymptotic lines of the BER and the ergodic capacity performance, the mixture gamma distribution is exploited. The closed-form expressions for these two kinds of asymptotic lines, both under the OSC and the MRC schemes, are proposed. The numerical simulations confirm that the proposed expressions fit well with the Monte-Carlo results. [ABSTRACT FROM AUTHOR]

Benzo[a]pyrene (BaP), a five-ring polycyclic aromatic hydrocarbon (PAH), which has carcinogenic potency, is highly recalcitrant and resistant to microbial degradation. A novel fungus, Lasiodiplodia theobromae ( L. theobromae), which can degrade BaP as a sole carbon source in liquid, was isolated in our laboratory. To prompt the further application of L. theobromae in remediation of sites polluted by BaP and other PAHs, the present study was targeted toward the removal of BaP and PAHs from soil by L. theobromae. The degradation of BaP by L. theobromae was studied using a soil spiked with 50 mg/kg BaP. L. theobromae could remove 32.1 % of the BaP after 35 days of cultivation. Phenanthrene (PHE) inhibited BaP degradation as a competitive substrate. The tested surfactants enhanced BaP degradation in soil by different extents, and a removal rate of 92.1 % was achieved at a Tween-80 (TW-80) concentration of 5 g/kg. It was revealed that TW-80 could not only enhance BaP bioavailability by increasing its aqueous solubility and decreasing the size of its colloid particles but also increase enzyme secretion from L. theobromae and the population of L. theobromae. Moreover, ergosterol content together with the biomass C indicated the increase in L. theobromae biomass during the BaP biodegradation process in soils. Finally, a soil from a historically PAH-contaminated field at Beijing Coking Plant in China was tested to assess the feasibility of applying L. theobromae in the remediation of polluted sites. The total removal rate of PAHs by L. theobromae was 53.3 %, which is 13.1 % higher than that by Phanerochaete chrysosporium ( P. chrysosporium), an effective PAH degrader. The addition of TW-80 to the field soil further enhanced PAH degradation to 73.2 %. Hence, L. theobromae is a promising novel strain to be implemented in the remediation of soil polluted by PAHs. [ABSTRACT FROM AUTHOR]

Optimal resource configuration is a critical issue for manufacturing grids. Economics is introduced for establishing a manufacturing grid resource marketplace and allocating resources based on market equilibrium and resource consumers’ utilities. Firstly, the resource allocation architecture is constructed based on the total framework of the manufacturing grid. Secondly, the economic environment of resource allocation is defined based on the characteristics of marketplace competitiveness, in which the feasible and Pareto optimization conditions of resource allocation are given. The competitive equilibrium of Pareto optimization is defined, in which resource owners may gain most economic profits, resource consumers gain maximal utilities and the market equilibrium was achieved. Finally, an iterative algorithm is introduced for the resource equilibrium price. The test results indicated that a resource price could be converged at its equilibrium price rapidly, and actual resources allocation result could be approximate to the equilibrium state. [ABSTRACT FROM AUTHOR]

Abstract  In this study, we investigated net primary production (NPP) and nutrient cycling in an apple orchard–annual crop system located in the Hill and Gully Region of the Loess Plateau, which included four production subsystems: Qinguan apple, Fuji apple, corn and millet. The results showed that NPP of corn (Zea mays L.) was two to three times greater than for millet (Setaria Italica L.) or apples (Malus domestica Borkh., cv ‘Fuji’ and ‘Qinguan’). Annual nutrient uptake by corn and millet was also much larger compared to apple trees. A comparison of nutrient use efficiency based on economic product showed that P and K use efficiency for Qinguan apples was about 50% greater compared to corn, while there was little difference in N use efficiency between apples and corn. More than 94% of the nutrients taken up by annual crops were lost from the system through the removal of grain and above-ground crop residue. In contrast, apple harvest and tree pruning resulted in the removal of 10–50% of the nutrients taken up annually by apple trees. Calculations indicated that farmers applied 60 times more N and 33 times more P to Qinguan apple orchards than was removed by apple harvest, but the amount of N and P fertilizer applied to corn was slightly less than the amount of N and P removed through crop harvest. In summary, the results indicated that increasing the proportion of land planted to apples and convincing farmers to leave annual crop residue in the fields would increase the sustainability of the apple orchard–annual crop system. Additional work needs to be done to determine the fate of N and P fertilizer applied to orchards as well as optimum fertilization rates for each of the four crops in the apple orchard–annual crop system. [ABSTRACT FROM AUTHOR]