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In the context of the circular economy, there is a need for advanced methods to recover metals from industrial waste, yet classical hydrometallurgical techniques are limited. Here, we review ultrasonic-assisted hydrometallurgical leaching with focus on the use of acids, bases, oxidants, bacteria and electrolysis. Oxidative leaching is done with ferric ions, dioxygen, ozone and hydrogen peroxide. Upscaling is also detailed. Ultrasonication allows to reduce the dosage of leaching agents, to reduce reaction time, and to enhance leaching efficiency. Large-scale equipments are still limited by low cavitation efficiency, low throughput, high usage costs, and high energy consumption. [ABSTRACT FROM AUTHOR]

To mitigate global carbon emissions, utilizing bio-based oils instead of petroleum for biodiesel production has emerged as a viable strategy. However, the development of efficient catalysts for the mild conversion of fatty acid esters (the mainly compounds of oils or fats) into diesel-range alkanes remains challenging due to the low reactivity of carbonyl group in esters. Herein, we report an efficient catalyst system for the hydrodeoxygenation of fatty acid esters into diesel-range alkanes under mild conditions over the RemNin@SiO2 catalyst. The catalyst containing a Re/Ni molar ratio of 1.0 showed the best catalytic performance, a 100% conversion and 96.3% selectivity towards n-octadecane/n-heptadecane(C18/C17) were obtained when using the methyl stearate as model compound under mild condition (170 °C and 2.5 MPa H2 pressure), surpassing the catalytic performance of the most catalytic systems reported so far. Characterization results showed that the excellent catalytic performance of the RemNin@SiO2 catalyst was mainly attributed to the formation of ReNi alloy, which enhanced the interaction between the catalyst and the oxygen atom of carbonyl group of esters, thereby activating the carbonyl group and promoting the deoxygenation of fatty acid esters under mild conditions. In addition, the synthesized Re1Ni1@SiO2 bimetallic catalyst has good stability, and after four cycles, the catalyst still exhibits high catalytic performance with above 90% alkane conversion. Re1Ni1@SiO2 catalyzed the hydrodeoxygenation of Methyl Stearate towards alkanes (C18/C17) under mild conditions. [ABSTRACT FROM AUTHOR]

Background The methylation of SHOX2 and RASSF1A shows promise as a potential biomarker for the early screening of lung cancer, offering a solution to remedy the limitations of morphological diagnosis. The aim of this study is to diagnose lung adenocarcinoma by measuring the methylation levels of SHOX2 and RASSF1A, and provide an accurate pathological diagnosis to predict the invasiveness of lung cancer prior to surgery. Material and methods The methylation levels of SHOX2 and RASSF1A were quantified using a LungMe® test kit through methylation-specific PCR (MS-PCR). The diagnostic efficacy of SHOX2 and RASSF1A and the cutoff values were validated using ROC curve analysis. The hazardous factors influencing the invasiveness of lung adenocarcinoma were calculated using multiple regression. Results: The cutoff values of SHOX2 and RASSF1A were 8.3 and 12.0, respectively. The sensitivities of LungMe® in IA, MIA and AIS patients were 71.3% (122/171), 41.7% (15/36), and 16.1% (5/31) under the specificity of 94.1% (32/34) for benign lesions. Additionally, the methylation level of SHOX2, RASSF1A and LungMe® correlated with the high invasiveness of clinicopathological features, such as age, gender, tumor size, TNM stage, pathological type, pleural invasion and STAS. The tumor size, age, CTR values and LungMe® methylation levels were identified as independent hazardous factors influencing the invasiveness of lung adenocarcinoma. Conclusion: SHOX2 and RASSF1A combined methylation can be used as an early detection indicator of lung adenocarcinoma. SHOX2 and RASSF1A combined (LungMe®) methylation is significantly correlated to age, gender, tumor size, TNM stage, pathological type, pleural invasion and STAS. The SHOX2 and RASSF1A methylation levels, tumor size and CTR values could predict the invasiveness of the tumor prior to surgery, thereby providing guidance for the surgical procedure. [ABSTRACT FROM AUTHOR]

Simple Summary: Pathogens of diseases in branches and trunks are commonly inoculated through punching, burning, and toothpick inoculation. At present, there is a lack of comparative analyses of the inoculation outcomes of these three methods. We determined that toothpick inoculation is an optimal option for studying the pathogenesis of Valsa sordida in six-year-old Populus alba var. pyramidalis, providing technical support for research on poplar diseases and offering a theoretical basis for the inoculation of other diseases in branches and trunks. A key step in the study of tree pathology is the identification of an appropriate method for inoculating pathogens of diseases in branches and trunks. Pathogens of diseases in branches and trunks are commonly inoculated through punching, burning, and toothpick inoculation. However, there is a lack of comparative analyses of the inoculation outcomes of these three methods. In this work, six-year-old P. alba var. pyramidalis were inoculated with V. sordida using punching, burning, and toothpick techniques to investigate the differences in the effectiveness of these inoculation methods. Results reveal that the incidence rate was 93.55% in the toothpick inoculation group, significantly higher than the 80.65% in the burning inoculation group (chi-square, n = 90, p = 0.007), while punching inoculation exhibited significant pathological responses in the early stages, with spontaneous healing in the later stage. Additionally, toothpick inoculation was more efficient in inducing Valsa canker when inoculating the pathogen at the bottom of the tree, with lower intra- and inter-row spacing (stand density) providing better outcomes than higher intra- and inter-row spacing. The results of this study demonstrate that toothpick inoculation is an optimal option for studying the artificial inoculation of V. sordida in six-year-old P. alba var. pyramidalis, providing technical support for research on poplar diseases and offering a theoretical basis for the inoculation of other diseases in the branch and trunk. [ABSTRACT FROM AUTHOR]

Insect infestations cause substantial changes in the leaves they attack, but the effects of insect infestation on photosynthesis and gene expression in the whole infestation period are rarely reported. In this study, the effects of poplar aphid (Chaitophorus populialbae Boyer de Fonscoloube) on photosynthetic rate and gene expression of Populus alba var. pyramidalis were studied, from 2 to 36 days after low-density aphid inoculation (DAI). The results revealed a dynamic change of photosynthesis in poplar after aphid infestation: compensatory increased at 8 DAI, was inhibited at 17 DAI, but repaired after 21 DAI. Aphid infestation promoted the expression of the majority of differentially expressed genes (DEGs) at 4, 6, 8, and 21 DAI. The DEGs were enriched into a plant–pathogen interaction, plant hormone signal transduction, and MAPK signaling pathway, suggesting a significant but transient resistance to disease or other stresses. Photosynthesis-related DEGs were downregulated at 8 DAI, which might result in photosynthetic inhibition at 17 DAI. The expression of flavonoid biosynthesis-related DEGs dynamic changed from all downregulated at 2 DAI to almost all upregulated at 21 DAI, suggesting a persistent resistance to insect infestation. This study reveals dynamic changes in photosynthesis, resistance to pathogens, and insects in poplar leaves after aphid infestation. [ABSTRACT FROM AUTHOR]

Triglycerides is a kind of natural oil widely existing in animals and plants, and it is also an ideal raw material for preparing biomass liquid fuel. Selectively hydrotreatment of unsaturated glyceride is an important strategy for the production of fuels and chemical feedstocks. In this work, catalytic hydrotreatment of triglycerides over Ni-based catalysts was investigated. Thus, an array of metal–organic frameworks derived Ni@C catalysts synthesized under different temperatures (350 °C, 400 °C, 450 °C) were prepared and applied for hydrotreatment of triglycerides. The highest conversion of triglycerides was 98.9% and the cracking rate could achieve 4.61% over the optimal Ni@C-BTC-400 catalyst in cyclohexane at 320 °C. The physicochemical characterizations were carried out by means of powder X-ray diffraction, scanning electronic microscopy, thermo gravimetric analyzer, N2 adsorption–desorption, and Raman. Based on the optimal reaction condition (320 °C, 3 h, 3.0 MPa H2), five typical vegetable oils and gutter oils were selected for the hydrotreatment study to investigate the adaptability of Ni@C-BTC-400 catalyst. The result indicated that Ni@C-BTC-400 catalyst performed good universality, and could transform oil raw materials with different fatty acid carbon chain structure to desired alkanes. Furthermore, the optimal Ni@C-BTC-400 catalyst could be carried out in next two consecutive recycling runs and could also be regenerated by H2 for the following experiments. [ABSTRACT FROM AUTHOR]

In this study, two poplar varieties with different resistance to sulfur dioxide were selected for a comparative experiment. SO2 fumigation to the poplars was carried out under controlled conditions to determine the variation in the activity of enzymes, the content of metabolites and the expression of enzymes genes in pathways of sulfur metabolism in plants. The results showed that the activity of enzymes and the content of sulfur metabolites were closely related to the response of the poplars to SO2 stress. Populus × euramericana cv. 'Purui' had two ways of detoxification: oxidation detoxification, oxidizing sulfite (SO32−) to sulfate SO42− by sulfite oxidase; reductive detoxification, SO32− being reduced to S2− by sulfite reductase (SiR). Moreover, OASTL and SAT activity, and levels of cysteine (CYS) and glutathione (GSH) also increased in P. × euramericana cv. 'Purui' in response to SO2 fumigation, and the gene expression encoding Glutathione S-transferases (GST), and some enzymes in cysteine and methionine metabolism was up-regulated. For Populus × euramericana cv. '74/76' with weaker resistance to sulfur dioxide, it only detoxified by increasing the activity of SiR, and but down-regulated the expression of gene encoding 3'-phosphoadenosine 5'-phosphosulfate synthase (PAPSS), which could affect the consumption of sulfite in the exposure to SO2. Thus, the SO2-resistant difference of the two poplar varieties is mainly attributed to variation in activity of the enzymes and content of their metabolites in pathways of sulfur metabolism, and gene expression of some enzymes in cysteine and methionine metabolism also plays a role in the resistant difference. [ABSTRACT FROM AUTHOR]

Botryosphaeriaceae , as a major family of the largest class of kingdom fungi Dothideomycetes , encompasses phytopathogens, saprobes, and endophytes. Many members of this family are opportunistic phytopathogens with a wide host range and worldwide geographical distribution, and can infect many economically important plants, including food crops and raw material plants for biofuel production. To date, however, little is known about the family evolutionary characterization, mating strategies, and pathogenicity-related genes variation from a comparative genome perspective. Here, we conducted a large-scale whole-genome comparison of 271 Dothideomycetes , including 19 species in Botryosphaeriaceae. The comparative genome analysis provided a clear classification of Botryosphaeriaceae in Dothideomycetes and indicated that the evolution of lifestyle within Dothideomycetes underwent four major transitions from non-phytopathogenic to phytopathogenic. Mating strategies analysis demonstrated that at least 3 transitions were found within Botryosphaeriaceae from heterothallism to homothallism. Additionally, pathogenicity-related genes contents in different genera varied greatly, indicative of genus-lineage expansion within Botryosphaeriaceae. These findings shed new light on evolutionary traits, mating strategies and pathogenicity-related genes variation of Botryosphaeriaceae. [ABSTRACT FROM AUTHOR]

Waste oil, like waste cooking and acidic oil, are two promising carboxylic acids feedstocks that can be converted into hydrocarbons by the pyrolytic method, usually through DCO 2 and DCO processes. DFT is employed to investigate the deoxygenation mechanism using octanoic acid as a model compound in this work. Additionally, pyrolysis of the above samples was carried out at atmospheric pressure, temperature below 773.15K. GC-MS, GC and TG-FTIR-MS test measures were used to analyze pyrolytic products. The DFT results reveal that pyrolysis conversion of waste oil was a direct and effective deoxygenation method. And high alkene content endowing pyrolytic oil greatly potential to upgrade for high-quality biofuel production. Finally, pyrolytic oil was upgraded by SAPO-11-Pd/C can increase the components of iso-hydrocarbons, further can faction cut to obtain three biofuel fractions. Fraction blending with fuels could decrease the cold filter plugging point of final fuels, dramatically improving the commercial value of pyrolytic oil and effectively solving the waste oil disposal problem. [Display omitted] • Deoxygenation mechanisms investigated by experiments analysis and DFT calculation. • Pyrolysis technology reagard as an efficient pretreatment method for wast oil deoxygenation. • Pyrolytic oil was upgraded by SPAO-11-Pd/C can increase the iso-hydrocarbons content. [ABSTRACT FROM AUTHOR]

Soap stocks are by-products obtained during the refining process of vegetable oil, and are mainly feedstocks to produce acidified oil. In this work, an efficient process was developed to convert soap stock into a high-quality biofuel with low impurity content. A combination of acidification and catalytic cracking reactions employed as pretreatment was investigated to decrease the impurity content in the soap stock feedstock for obtaining a value-added biofuel. A high olefin content (approximately 47%) pyrolytic oil was obtained during the pretreatment. For further improvement of the cold flow properties, hydro-isomerization of pyrolytic oil for the formation of iso-alkanes over the Ce–Pt/SAPO-11and Ce–Pt/ZSM-5 catalysts was then carried out. The isomerization reaction temperature could be decreased to 320 °C because of the approximately 47% olefin content. The cold filter plugging point (CFPP) of the resulting product could be obtained at −11 °C, and the sulfur content could be decreased to lower than 10 ppm, which could meet the EN and ASTM specifications. [ABSTRACT FROM AUTHOR]

Recognition of human poses and actions is crucial for autonomous systems to interact smoothly with people. However, cameras generally capture human poses in 2D as images and videos, which can have significant appearance variations across viewpoints that make the recognition tasks challenging. To address this, we explore recognizing similarity in 3D human body poses from 2D information, which has not been well-studied in existing works. Here, we propose an approach to learning a compact view-invariant embedding space from 2D body joint keypoints, without explicitly predicting 3D poses. Input ambiguities of 2D poses from projection and occlusion are difficult to represent through a deterministic mapping, and therefore we adopt a probabilistic formulation for our embedding space. Experimental results show that our embedding model achieves higher accuracy when retrieving similar poses across different camera views, in comparison with 3D pose estimation models. We also show that by training a simple temporal embedding model, we achieve superior performance on pose sequence retrieval and largely reduce the embedding dimension from stacking frame-based embeddings for efficient large-scale retrieval. Furthermore, in order to enable our embeddings to work with partially visible input, we further investigate different keypoint occlusion augmentation strategies during training. We demonstrate that these occlusion augmentations significantly improve retrieval performance on partial 2D input poses. Results on action recognition and video alignment demonstrate that using our embeddings without any additional training achieves competitive performance relative to other models specifically trained for each task. [ABSTRACT FROM AUTHOR]

Hydrothermal CO2-assisted pretreatment was carried out for selective degradation of hemicellulose in wheat straw to produce pentose and enhancement the efficiency of enzymatic hydrolysis for glucose production. The FT-IR analysis and HPLC method was adopted to determine the observed chemical composition. Up to 90.0% of hemicelluloses were degraded under the optimum condition with temperature of 200 °C, CO2 pressure of 3 MPa and reaction time of 10 min, following with cellulose content in substrate increase from 37.6 to 58.1%. The efficiency of enzymatic hydrolysis was significantly improved after pretreatment, attributing to the loose structure of lignocelluloses after hemicellulose removal. More than 72.7% of glucose was achieved after enzymatic hydrolysis, by contrast, while the untreated sample was merely 30.2% due to enzymatic indigestibility. Additionally, SEM observations demonstrated that the densified structure of substrate was destructed, enhancing the accessibility and absorption of enzymes in the hydrolysis processing. The current results indicated that the hydrothermal CO2-assisted pretreatment was a feasible and effective approach for pretreatment of lignocellulosic biomass. [ABSTRACT FROM AUTHOR]

Time series classification (TSC) arises in many fields and has a wide range of applications. Here, we adopt the bag-of-words (BoW) framework to classify time series. Our algorithm first samples local subsequences from time series at feature-point locations when available. It then builds local descriptors, and models their distribution by Gaussian mixture models (GMM), and at last it computes a Fisher Vector (FV) to encode each time series. The encoded FV representations of time series are readily used by existing classifiers, e.g., SVM, for training and prediction. In our work, we focus on detecting better feature points and crafting better local representations, while using existing techniques to learn codebook and encode time series. Specifically, we develop an efficient and effective peak and valley detection algorithm from real-case time series data. Subsequences are sampled from these peaks and valleys, instead of sampled randomly or uniformly as was done previously. Then, two local descriptors, Histogram of Oriented Gradients (HOG-1D) and Dynamic time warping-Multidimensional scaling (DTW-MDS), are designed to represent sampled subsequences. Both descriptors complement each other, and their fused representation is shown to be more descriptive than individual ones. We test our approach extensively on 43 UCR time series datasets, and obtain significantly improved classification accuracies over existing approaches, including NNDTW and shapelet transform. [ABSTRACT FROM PUBLISHER]

It is of great importance to explore the selective hydrogenolysis of β-O-4 linkages, which account for 45–60% of all linkages in native lignin, to produce valued-added chemicals and fuels from biomass employing UV light as catalyst. TiO2 exhibited satisfactory catalytic performances in various photochemical reactions, due to its versatile advantages involving high catalytic activity, low cost and non-toxicity. In this work, 20 wt.% Ni/TiO2 and oxidant PCC (Pyridinium chlorochromate) were employed to promote the cleavage of β-O-4 alcohol to obtain high value chemicals under UV irradiation at room temperature. The Ni/TiO2 photocatalyst can be magnetically recovered and efficiently reused in the following four consecutive recycling tests in the cleavage of β-O-4 ether bond in lignin. Mechanism studies suggested that the oxidation of β-O-4 alcohol to β-O-4 ketone by oxidant PCC first occurred during the reaction, and was followed by the photocatalysis of the obtained β-O-4 ketone to corresponding acetophenone and phenol derivates. Furthermore, the system was tested on a variety of lignin model substrates containing β-O-4 linkage for the generation of fragmentation products in good to excellent results. [ABSTRACT FROM AUTHOR]

Carbon starvation is the current leading hypothesis of plant mortality mechanisms under drought stress; recently, it is also used to explain tree die-off in plant diseases. However, the molecular biology of the carbon starvation pathway is unclear. Here, using a punch inoculation system, we conducted transcriptome and physiological assays to investigate pathogen response in poplar stems at the early stages of Botryosphaeria and Valsa canker diseases. Transcriptome assays showed that the majority of differentially expressed genes (DEGs) in stem phloem and xylem, such as genes involved in carbon metabolism and transportation, aquaporin genes (in xylem) and genes related to the biosynthesis of secondary metabolites and the phenylpropanoid pathway (related to lignin synthesis), were downregulated at 7 days after inoculation (DAI). Results also showed that the expression of the majority of disease-resistance genes upregulated in poplar stems, which may be connected with the downregulation expression of the majority of WRKY family genes. Physiological assays showed that transpiration rate decreased but WUE (water use efficiency) increased the 3 and 7 DAI, while the net photosynthetic rate decreased at 11 DAI in Botryosphaeria infected poplars (ANOVA, P < 0.05). The NSC (non-structural carbohydrates) content assays showed that the soluble sugar content of stem phloem samples increased at 3, 7, and 11 DAI that might due to the impede of pathogen infection. However, soluble sugar content of stem xylem and root samples decreased at 11 DAI; in contrast, the starch content unchanged. Therefore, results revealed a chronological order of carbon related molecular and physiological performance: declination of genes involved in carbon and starch metabolism first (at least at 7 DAI), declination of assimilation and carbon reserve (at 11 DAI) second. Results implied a potential mechanism that affects the host carbon reserve, by directly inhibiting the expression of genes involved in carbon metabolism and transport. [ABSTRACT FROM AUTHOR]

Embryo implantation in the mink follows the pattern of many carnivores, in that preimplantation embryo diapause occurs in every gestation. Details of the gene expression and regulatory networks that terminate embryo diapause remain poorly understood. Illumina RNA-Seq was used to analyze global gene expression changes in the mink uterus during embryo diapause and activation leading to implantation. More than 50 million high quality reads were generated, and assembled into 170,984 unigenes. A total of 1684 differential expressed genes (DEGs) in uteri with blastocysts in diapause were compared to the activated embryo group (p < 0.05). Among these transcripts, 1527 were annotated as known genes, including 963 up-regulated and 564 down-regulated genes. The gene ontology terms for the observed DEGs, included cellular communication, phosphatase activity, extracellular matrix and G-protein couple receptor activity. The KEGG pathways, including PI3K-Akt signaling pathway, focal adhesion and extracellular matrix (ECM)-receptor interactions were the most enriched. A protein-protein interaction (PPI) network was constructed, and hub nodes such as VEGFA, EGF, AKT, IGF1, PIK3C and CCND1 with high degrees of connectivity represent gene clusters expected to play an important role in embryo activation. These results provide novel information for understanding the molecular mechanisms of maternal regulation of embryo activation in mink. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome (mtDNA) of Peking duck (Anas platyrhychos) was determined. The entire genome was 16,604 bp in length. Similar to the typical mtDNA of vertebrates, it contained 37 genes (13 protein-coding genes, 2 rRNA genes, 22 tRNA genes) and a non-coding region (D-loop). The characteristics of the mitochondrial genome was analyzed and discussed in detail. [ABSTRACT FROM AUTHOR]

The raccoon dog (Nyctereutes procyonoides) is an important canid fur-bearing animal species worldwide. Chinese raccoon dogs that present a white mutation, especially those with a white coat. Exploring melanin biosynthesis in the hair and skin of raccoon dogs is important for understanding the survival and evolutionary mechanisms of them. In this study, we measured the content of melanin in the hair of two types of raccoon dog and generated stained slices of skin tissue. The results indicated that melanin biosynthesis occurs in the wild-type (W) and white-type (B) raccoon dog skin, although less melanin is produced in B skin. We then sequenced the skin transcriptomes of W and B, compared the similarities and differences in expressed genes. A comparison of the gene expression showed 60 up-regulated genes and 127 down-regulated genes in B skin. We analyzed the unigenes and pathways related to the melanogenesis pathway and found that TYR, TYRP1, MC1R, SLC24a5, SLC45a2 and OCA2 were significantly down-regulated in B skin and these results were verified via qRT-PCR. We surmised that the phenotypic characteristics of the white mutation might be caused by the reduced expression of these genes and this finding provides new insights for future experiments in raccoon dogs. [ABSTRACT FROM AUTHOR]