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This review surveyed different mechanisms for the separation of oil/water mixtures and the corresponding materials. Special attention has been given to the separation types based on different oil/water mixtures, surface wettability and structures.

This study aimed to reveal the potential genes and mechanisms involved in the biosynthesis of quercetin (QCT) in maize (Zea mays L.) through genome-wide association study (GWAS) and bioinformatics analysis, and provide a basis for further research on QCT. The content of QCT in 196 maize inbred lines was detected by LC-MS. The single-nucleotide polymorphism (SNPs) data from these samples were explored by Maize 55K SNP arrays, followed by population structure using fastStructure software and genome-wide association study (GWAS) analysis. Then, the SNP screening was performed with P < 1.00E-06 using Gramene software, followed by SNP annotation (150 KB up and downstream). The enrichment analysis was performed on all annotated genes. Finally, the protein-protein interaction (PPI) network analysis was performed to further reveal the relations among genes. A total of 12 SNPs were explored from original SNPs with P < 1.00E-06. The SNP annotation revealed several SNP-associated genes including Zm00001d036822 and Zm00001d007407. These genes were mainly enriched in metabolic pathway and functions like negative regulation of cell cycle phase transition. Finally, a PPI work was constructed by totally 34 annotated genes and 59 interactions. Zm00001d036822 and Zm00001d007407 might be novel candidate genes involved in the synthesis of QCT. Meanwhile, the metabolic pathway as well as negative regulation of cell cycle phase transition function might contribute to the biosynthesis of QCT.

Solar energy used to evaporate seawater and purify fresh water is regarded as an innovative way to address water scarcity. In this paper, high-performance porous wood-carbonized solar steam evaporation (SSE) is proposed by regulating the surface carbonization process, and the evaporation performance of the SSE under different carbonization degrees is studied. The results show that the variation in carbonization degree treatment can significantly affect the photothermal conversion characteristics, which in turn affect the evaporation efficiency of solar steam evaporation. Surprisingly, at 1 sun equivalent input, this evaporator exhibits a low thermal conductivity (0.17 W m−1 K−1), high solar energy absorption rate (92.5%), high surface temperature (49.5 °C) and evaporation efficiency (78%). When the surface carbonization degree of the SSE is 20%, an excellent thermal conductivity coefficient (0.33 W m−1 K−1) is available by the efficient water conduction ability. Additionally, an outstanding evaporation rate (1.8 kg m−2 h−1) of the SSE can be obtained, which is significantly superior to that of the reported wood-based evaporators. Due to its simple preparation, wood-based SSE with recyclability, low-cost and extraordinary performance can be expected to provide potential fresh water for commercial and renewable applications.

Background Tendon-ligament injuries (TLIs), including Achilles tendinopathy, cruciate ligament injury, tennis elbow, rotator cuff injury, patellar tendinopathy, and tibial tendinopathy, are common musculoskeletal soft injuries during physical activity. Matrix metalloproteinase-3 (MMP-3) gene polymorphisms have been implicated in the etiology of TLIs in several genetic association studies with inconsistent results. The purpose of this study was to collect and synthesize the current evidences on the association of MMP-3 polymorphisms and TLIs. Methods The search was conducted using PubMed, Web of Science, EMBASE, Cochrane Library, CNKI and Wanfang databases, prior to July, 2021. Newcastle Ottawa Scale was used to appraise the study quality. Strengths of association were represented by odds ratios (ORs) and 95% confidence intervals (95% CIs). Results Thirteen studies with 2871 cases and 4497 controls met the eligibility criteria, and each study was in high quality. The overall analyzes suggested rs3025058 was associated with an increased TLIs risk (5A vs. 6A, OR = 1.20, 95% CI 1.03–1.40, P = 0.020). However, the association was not found for rs679620, rs591058, and rs650108 polymorphisms. Subgroup analysis by injury type suggested that rs679620 polymorphism was associated with a reduced risk to Achilles tendon rupture (AA + AG vs. GG, OR = 0.46, 95% CI 0.25–0.87, P = 0.020), and rs3025058 was associated with an elevated risk to anterior cruciate ligament injury (5A5A + 5A6A vs. 6A6A, OR = 1.46, 95% CI 1.03–2.06, P = 0.030). When stratified by ethnicity, the findings indicated that rs3025058 polymorphism was associated with an increased TLIs risk among Caucasians (5A6A vs. 6A6A, OR = 1.55, 95% CI 1.09–2.42, P = 0.020) and Brazilians (5A5A vs. 5A6A + 6A6A, OR = 2.80, 95% CI 1.44–5.45, P = 0.002). Conclusion Findings of this study suggest that rs679620 polymorphism is associated with a reduced Achilles tendon rupture risk, and rs3025058 polymorphism contributes to an increased TLIs risk in Caucasians and Brazilians. However, rs591058 and rs650108 polymorphisms do not show any association with TLIs.

Studies on solar steam evaporation for potential application in desalination have attracted much attention due to its unique advantages of low energy consumption environmental friendliness, etc. However, water molecule transportation in the capillaries of solar steam evaporators to develop a high-efficiency solar evaporation system is critical but often ignored. This work reports high-yield and low-cost natural corn stalks as solar steam generators with ultra-fast water transportation in capillaries, multi-layer self-cleaning of sea salt, large seawater storage capacity, long-term anti-corrosion properties against seawater, low thermal conductivity, and excellent evaporation properties. This solar steam evaporator with the conventional photothermal coating by multi-walled carbon nanotubes and titanium dioxide (Mcnt-TiO2) exhibits an outstanding evaporation rate of 2.48 kg m−2 h−1 and evaporation efficiency of 68.2% under solar light. These advantages are significantly attributed to the natural structural features of the stem marrow of corn stalks including scattered vascular bundles with super-hydrophilic properties achieving high-speed water moisture transportation, porous basic tissues with layer by layer bio-filtration, porous cavities realizing multi-stage filtration, transportation and storage of seawater, and low moisture enthalpy and heat loss. Meanwhile, an efficient and low-cost solar desalination device via bundling pluralities of corn stalks is developed to collect freshwater, and the average daily freshwater amount per unit area (4.3–5.8 kg m−2 on sunny days and 3.0–3.9 kg m−2 on cloudy days) can meet the daily water needs of more than twenty adults. These findings not only provide the possibility of discovering corn stalks as low-cost, scalable, highly efficient evaporation-based heat transfer devices for future efficient desalination, but also present an innovative inspiration for reducing the greenhouse effect brought by corn stalk burning, which promotes the efficient use of bio-mass straws.

Solar steam evaporation is regarded as a green and efficient method to achieve desalination and purification. However, the low-efficiency photothermal conversion of its evaporator is an obstacle to widespread application. Focusing on the interface evaporation method through photothermal conversion, the current bottleneck of the technology is that it is impossible to achieve in-depth interface control of the incident light path to obtain higher water evaporation efficiency. We propose a mesoporous cellulose-based hydrogel for the manufacture of a high-efficiency solar steam evaporator. This type of solar evaporator achieves an enhanced capillary force and optical path extension to increase the photothermal conversion efficiency and evaporation rate. These evaporation performance advantages can all be attributed to the dense mesoporous structure, low thermal conductivity, and high light absorption efficiency. The results showed that under a solar light intensity of 1.5 kW m−2, the mesoporous structure of the MCNT–TiO2–SiO2–TiN hydrogel-based evaporator has an excellent evaporation rate (1.853 kg m−2 h−1) and high solar energy conversion efficiency (77.39%) due to the low thermal conductivity (0.71997 W m−1 k−1), high light absorption efficiency (98.3%, wavelength 190–3000 nm) and good hydrophilic properties (XRD and FT-IR tests). Our results demonstrate a new full-hydrogel solar steam evaporation method by using a simple, easily obtained, reusable, and low-cost solar desalination and purification system based on evaporation can yield fresh water from seawater and sewage. The evaporation technique can be used to produce a simple, easily obtained, reusable, and low-cost solar desalination and purification system for pure freshwater resources from seawater and sewage.

Recently, deep neural network-based image compressed sensing methods have achieved impressive success in reconstruction quality. However, these methods (1) have limitations in sampling pattern and (2) usually have the disadvantage of high computational complexity. To this end, a fast multi-scale generative adversarial network (FMSGAN) is implemented in this paper. Specifically, (1) an effective multi-scale sampling structure is proposed. It contains four different kernels with varying sizes so that decompose, and sample images effectively, which is capable of capturing different levels of spatial features at multiple scales. (2) An efficient lightweight multi-scale residual structure for deep image reconstruction is proposed to balance receptive field size and computational complexity. The key idea is to apply smaller convolution kernel sizes in the multi-scale residual structure to reduce the number of operations while maintaining the receptive field. Meanwhile, the channel attention structure is employed for enriching useful information. Moreover, perceptual loss is combined with MSE loss and adversarial loss as the optimization function to recover a finer image. Numerous experiments show that our FMSGAN achieves state-of-the-art image reconstruction quality with low computational complexity.

Maize often exhibits asynchronous pollination under abiotic and biotic stress conditions; however, the molecular basis of this developmental deficiency has not been elucidated. Tassel development is a key process affecting the anthesis-silking interval (ASI) in maize. In this study, we showed that pollen shedding was delayed and ASI was significantly increased in B73 and Chang7-2 inbred lines under water deficit conditions, which resulted in longer barren tip length and decreased yields under both controlled and field conditions. Comparative transcriptome analysis performed on immature tassels derived from plants grown under well-watered and water deficit conditions identified 1931 and 1713 differentially expressed genes (DEGs) in B73 and Chang7-2, respectively. Further, 28 differentially co-expressed transcription factors were identified across both lines. Collectively, we demonstrated that the molecular regulation of tassel development is associated with water deficit stress at early vegetative stage in maize. This finding extends our understanding of the molecular basis of maize tassel development during abiotic stress.

Patterned surfaces can enhance the sensitivity of laser desorption ionization mass spectrometry by segregating and concentrating analytes, but their fabrication can be challenging. Here, we describe a simple method to fabricate substrates patterned with micron-scale wells that yield more accurate and sensitive mass spectrometry measurements compared to flat surfaces. The wells can also concentrate and localize cells and beads for cell-based assays.

We used the molecular modeling program Rosetta to identify clusters of amino acid substitutions in antibody fragments (scFvs and scAbs) that improve global protein stability and resistance to thermal deactivation. Using this methodology, we increased the melting temperature (T(m)) and resistance to heat treatment of an antibody fragment that binds to the Clostridium botulinum hemagglutinin protein (anti-HA33). Two designed antibody fragment variants with two amino acid replacement clusters, designed to stabilize local regions, were shown to have both higher T(m) compared to the parental scFv and importantly, to retain full antigen binding activity after 2 hours of incubation at 70 °C. The crystal structure of one thermostabilized scFv variants was solved at 1.6 Å and shown to be in close agreement with the RosettaAntibody model prediction.

Summary Polycyclic aromatic hydrocarbons (PAHs) are highly toxic, pervasive environmental pollutants with mutagenic, teratogenic, and carcinogenic properties. There is interest in exploiting the nutritional capabilities of microbes to remove PAHs from various environments including those impacted by improper disposal or spills. Although there is a considerable body of literature on PAH degradation, the substrates and products for many of the enzymes have never been identified and many proposed activities have never been confirmed. This is particularly true for high molecular weight PAHs (e.g., phenanthrene, fluoranthene, and pyrene). As a result, pathways for the degradation of these compounds are proposed to follow one elucidated for naphthalene with limited experimental verification. In this pathway, ring fission produces a species that can undergo a non-enzymatic cyclization reaction. An isomerase opens the ring and catalyzes a cis to trans double bond isomerization. The resulting product is the substrate for a hydratase-aldolase, which catalyzes the addition of water to the double bond of an α,β-unsaturated ketone, followed by a retro-aldol cleavage. Initial kinetic and mechanistic studies of the hydratase-aldolase in the naphthalene pathway (designated NahE) and two hydratase-aldolases in the phenanthrene pathway (PhdG and PhdJ) have been completed. Crystallographic work on two of the enzymes (NahE and PhdJ) provides a rudimentary picture of the mechanism and a platform for future work to identify the structural basis for catalysis and the individual specificities of these hydratase-aldolases.

NahE and PhdJ are bifunctional hydratase-aldolases in bacterial catabolic pathways for naphthalene and phenanthrene, respectively. Bacterial species with these pathways can use polycyclic aromatic hydrocarbons (PAHs) as sole sources of carbon and energy. Because of the harmful properties of PAHs and their widespread distribution and persistence in the environment, there is great interest in understanding these degradative pathways, including the mechanisms and specificities of the enzymes found in the pathways. This knowledge can be used to develop and optimize bioremediation techniques. Although hydratase-aldolases catalyze a major step in the PAH degradative pathways, their mechanisms are poorly understood. Sequence analysis identified NahE and PhdJ as members of the N-acetylneuraminate lyase (NAL) subgroup in the aldolase superfamily. Both have a conserved lysine and tyrosine (for Schiff base formation) as well as a GXXGE motif (to bind the pyruvoyl carboxylate group). Herein, we report the structures of NahE, PhdJ, and PhdJ covalently bound to substrate via a Schiff base. Structural analysis and dynamic light scattering experiments show that both enzymes are tetramers. A hydrophobic helix insert, present in the active sites of NahE and PhdJ, might differentiate them from other NAL subgroup members. The individual specificities of NahE and PhdJ are governed by Asn-281/Glu-285 and Ser-278/Asp-282, respectively. Finally, the PhdJ complex structure suggests a potential mechanism for hydration of substrate and subsequent retro-aldol fission. The combined findings fill a gap in our mechanistic understanding of these enzymes and their place in the NAL subgroup.

5-Halo-2-hydroxy-2,4-pentadienoates (5-halo-HPDs) are reportedly generated in the bacterial catabolism of halogenated aromatic hydrocarbons by the meta-fission pathway. The 5-halo-HPDs, where the halogen can be bromide, chloride, or fluoride, result in the irreversible inactivation of 4-oxalocrotonate tautomerase (4-OT), which precedes the enzyme that generates them. The loss of activity is due to the covalent modification of the nucleophilic amino-terminal proline. Mass spectral and crystallographic analysis of the modified enzymes indicate that inactivation of 4-OT by 5-chloro- and 5-bromo-2-hydroxy-2,4-pentadienoate follows a different mechanism than that for the inactivation of 4-OT by 5-fluoro-2-hydroxy-2,4-pentadienoate. The 5-chloro- and 5-bromo derivatives undergo 4-OT-catalyzed tautomerization to their respective α-unsaturated ketones followed by attack at C-5 (by the prolyl nitrogen) with concomitant loss of the halide. For the 5-fluoro species, the presence of a small amount of the α,β-unsaturated ketone could result in a Michael addition of the prolyl nitrogen to C-4 followed by protonation at C-3. The fluoride is not eliminated. These observations suggest that the inactivation of 4-OT by a downstream metabolite could hamper the efficacy of the pathway, which is the first time that such a bottleneck has been reported for the meta-fission pathway.

Maize kernel development is a complex biological process that involves the temporal and spatial expression of many genes and fine gene regulation at a transcriptional and post-transcriptional level, and microRNAs (miRNAs) play vital roles during this process. To gain insight into miRNA-mediated regulation of maize kernel development, a deep-sequencing technique was used to investigate the dynamic expression of miRNAs in the embryo and endosperm at three developmental stages in B73. By miRNA transcriptomic analysis, we characterized 132 known miRNAs and six novel miRNAs in developing maize kernel, among which, 15 and 14 miRNAs were commonly differentially expressed between the embryo and endosperm at 9 days after pollination (DAP), 15 DAP and 20 DAP respectively. Conserved miRNA families such as miR159, miR160, miR166, miR390, miR319, miR528 and miR529 were highly expressed in developing embryos; miR164, miR171, miR393 and miR2118 were highly expressed in developing endosperm. Genes targeted by those highly expressed miRNAs were found to be largely related to a regulation category, including the transcription, macromolecule biosynthetic and metabolic process in the embryo as well as the vitamin biosynthetic and metabolic process in the endosperm. Quantitative reverse transcription-PCR (qRT-PCR) analysis showed that these miRNAs displayed a negative correlation with the levels of their corresponding target genes. Importantly, our findings revealed that members of the miR169 family were highly and dynamically expressed in the developing kernel, which will help to exploit new players functioning in maize kernel development.

Ultraviolet photodissociation (UVPD) mass spectrometry (MS) was used to characterize the sequences of proteins in native protein-ligand and protein-protein complexes and to provide auxiliary information about the binding sites of the ligands and protein-protein interfaces. UVPD outperformed collisional induced dissociation (CID), higher-energy collisional dissociation (HCD), and electron transfer dissociation (ETD) in terms of yielding the most comprehensive diagnostic primary sequence information about the proteins in the complexes. UVPD also generated noncovalent fragment ions containing a portion of the protein still bound to the ligand which revealed some insight into the nature of the binding sites of myoglobin/heme, eIF4E/m(7)GTP, and human peptidyl-prolyl cis-trans isomerase 1 (Pin1) in complex with the peptide derived from the C-terminal domain of RNA polymerase II (CTD). Noncovalently bound protein-protein fragment ions from oligomeric β-lactoglobulin dimers and hexameric insulin complexes were also produced upon UVPD, providing some illumination of tertiary and quaternary protein structural features.