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Although (sub)tropical forests account for 10–20% of the atmospheric methane (CH 4) uptake by soils, the study of soil CH 4 oxidation rates and the controlling factors during the chronosequences of forest succession remains poorly understood. The objectives of this study were to characterize the vertical distribution patterns and dynamics of CH 4 oxidation among the early-, mid-, and late-successional stages of subtropical forests, and to investigate the main drivers of soil CH 4 fluxes. Three successional forests soils were collected and the ambient and potential CH 4 oxidation rates, the related enzymes as well as the key soil parameters were determined in the laboratory. The soils at mid- and late-successional stages functioned exclusively as a CH 4 sink while the soil at early-succesional stage was either a CH 4 source or sink. Soil CH 4 oxidations showed significant vertical distributions along with the successional gradients. The highest rate of ambient CH 4 oxidation was observed in the A-horizon of the mid-successional stage (forest age ∼ 100 years), increased by 26-fold compared to the early successional stage, while the highest rate of potential CH 4 oxidation was detected in the O-horizon of the late-successional stages (forest age > 300 years), which increased the CH 4 oxidation by 29% and 21% respectively compared to the early- and mid-successional stages. Soil CH 4 oxidation enhanced with decreasing of soil nitrite and nitrate content but weakened with declining of soil moisture at the successional chronosequence. Collectively, subtropical forests have the potential to increase the soil sink capacity for CH 4 oxidation along the successional gradient, and thereby providing the negative feedbacks to ecosystems under climate changing. [ABSTRACT FROM AUTHOR]

Angiogenesis inhibitors and photosensitizers are pivotal in tumor clinical treatment, yet their utilization is constrained. Herein, eleven novel angiogenesis inhibitors were developed through hybridization strategy to overcome their clinical limitations. These title compounds boast excitation wavelengths within the "therapeutic window", enabling deep tissue penetration. Notably, they could generate superoxide anion radicals via the Type I mechanism, with compound 36 showed the strongest superoxide anion radical generating capacity. Biological evaluation demonstrated remarkable cellular activity of all the title compounds, even under hypoxic conditions. Among them, compound 36 stood out for its superior anti-proliferative activity in both normoxic and hypoxic environments, surpassing individual angiogenesis inhibitors and photosensitizers. Compound 36 induced cell apoptosis via superoxide anion radical generation, devoid of dark toxicity. Molecular docking revealed that the target-recognizing portion of compound 36 was able to insert into the ATP binding pocket of the target protein similar to sorafenib. Collectively, our results suggested that hybridization of angiogenesis inhibitors and photosensitizers was a potential strategy to address the limitations of their clinical use. Discovery of novel angiogenesis inhibitors which could address the clinical limitations of both angiogenesis inhibitors and photosensitizers. [Display omitted] • Novel angiogenesis inhibitors were designed and synthesized through adopting hybridization strategy. • Novel angiogenesis inhibitors could address clinical limitations of both angiogenesis inhibitors and photosensitizers. • Sorafenib might be used as an amplifier to enhance the reactive oxygen generation capacity of photosensitizers. [ABSTRACT FROM AUTHOR]

Bacillus cereus is a spore-forming gastrointestinal pathogen that can cause life-threatening diseases. Here, a simple and effective assay to detect B. cereus was developed, using cross-priming amplification (CPA). Amplicons were detected using disposable cartridges that contained nucleic acid detection strips. The sensitivity of CPA assay for B. cereus was assessed using serial dilutions of genomic DNA, which indicated a detection limit of 3.6 × 101 CFU/mL. No cross-reactions were detected when genomic DNA extracted from 12 different B. cereus strains and 20 other bacterial foodborne strains were tested, suggesting that the assay is highly specific. Finally, we evaluated the practical applications of the CPA assay for the detection of B. cereus in 150 food samples and found that its sensitivity and specificity, compared with real-time PCR, were approximately 98.18 and 100%, respectively. In conclusion, CPA combined with nucleic acid detection strips is easy to perform, requires simple equipment, and offers highly specific and sensitive B. cereus detection. A novel CPA method was developed to detect Bacillus cereus. CPA detects B. cereus with high sensitivity and specificity in less than 2 h. A disposable cartridge detects the amplicon, which prevents cross-contamination. The assay is easy to use and allows B. cereus detection in resource-limited areas. [ABSTRACT FROM AUTHOR]

Two ternary mixed oxides, Ru-Mn-Ce and Ru-Co-Ce, were prepared by a co-precipitation method and used in the aerobic oxidation of alcohols to corresponding aldehydes (ketones). Interestingly, different catalytic results were obtained when these compounds were calcined. The calcination temperature had an adverse effect on the catalytic performance of Ru-Mn-Ce catalysts, while being beneficial to the Ru-Co-Ce catalysts. To illustrate these effects, these materials were characterized using X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), Temperature-programmed reduction (TPR), Electron paramagnetic resonance (EPR) and other techniques. The data showed that ruthenium oxides were uniformly dispersed in the mixed oxides, and phase transformations occur after calcination. Mn 3 O 4 was transformed to MnO 2 for the Ru-Mn-Ce catalyst, while CoO(OH) was transformed to Co 3 O 4 in the Ru-Co-Ce catalyst . The interactions between ruthenium oxides and Co (Mn)-Ce mixed oxides of the former strengthened while the latter weakened. Calcination decreased the content of adsorbed oxygen and restricted oxygen transfer mechanism in the manganese system, while the opposite effect was observed with the cobalt-containing catalyst. Under optimal reaction conditions, various kinds of alcohols were transformed to corresponding aldehydes (ketones) in high yields over the Ru-Mn-Ce catalyst suggesting these ternary oxides are environmental friendly and economical catalytic systems. [ABSTRACT FROM AUTHOR]

Vermicomposting is a biotechnology similar to composting but is more effective at degrading organic waste. Earthworms engulf the waste and digest it through the gut to form manure fertilizer. However, the nitrogen loss caused by nitrous oxide (N 2 O) can reduce the fertilization value of vermicompost and contribute to global warming. In the last decade, an increasing number of studies have focused on the effect of vermicomposting on N 2 O emissions. However, the results are contradictory, and a quantitative summary of these studies is still missing. In this study, a meta-analysis was conducted to evaluate the effects of the two phases (vermicompost preparation and vermicompost application) of vermicomposting on N 2 O emissions and their relationship with substrate and soil properties (e.g., substrate type, C/N ratio, soil pH, and moisture). Our results showed that the vermicompost preparation insignificantly increased N 2 O emissions compared with traditional composting (without earthworms), and the amounts of N 2 O generated during the phase of preparation were 3–143 times higher than those of the application phase. Interestingly, it is the vermicompost application phase, rather than preparation, that showed a positive effect size on N 2 O emissions (87 %), and the effects were highly dependent on the soil and substrate C/N ratio. A vermicomposting duration of ≥90 days promoted N 2 O emissions, and the vermicomposting effect size of the cumulative N 2 O emission was positively correlated with the temperature, soil C/N ratio and soil organic carbon (SOC) content but negatively correlated with the water-filled pore space (WFPS). Our findings indicated that, in the two phases of vermicomposting, organic matter was decomposed with the simultaneous consumption of oxygen, which accelerated N mineralization in the environment and in the guts of earthworms. As a result, nitrification and microsite denitrification were promoted, which enhanced the production of N 2 O. Our meta-analysis highlighted the necessity of connecting the effect of vermicomposting with soil and substrate C/N ratio to mitigate soil N 2 O emissions. [Display omitted] [ABSTRACT FROM AUTHOR]

• The discovery of superconductivity in the infinite-layer nickelates has motivated tremendous efforts for its' significance toward the understanding of superconductivity. However, the synthesis of infinite-layer nickelates is instable and has become a holdback to experimental progress. • Previous reports have pointed out that the precursor perovskite Nd 0.8 Sr 0.2 NiO 3 phase is an essential precondition to achieve the superconducting Nd 0.8 Sr 0.2 NiO 2 thin films, while an impurity phase with the Ruddlesden-Popper (RP) structure which hinders the implementation of superconductivity is inevitable during the growth of the Nd 0.8 Sr 0.2 NiO 3 phase. • Our study shows that the inevitable impurity phase with the Ruddlesden-Popper structure is strongly affected by the laser fluence during the growth of the precursor perovskite Nd 0.8 Sr 0.2 NiO 3 phase. And we believe that our study can further promote the research of nickelate superconductivity in terms of experimentation. The discovery of superconductivity in the infinite-layer nickelates has motivated tremendous efforts for its' significance toward the understanding of superconductivity. However, the synthesis of infinite-layer nickelates is instable and has become a holdback to experimental progress. According to systematic growth with variable conditions, our study suggests that the synthesis of the precursor perovskite Nd 0.8 Sr 0.2 NiO 3 phase is very crucial for the whole experimental progress, whereas the topotactic reduction has a relative wide window of reduction condition. What is more, the laser fluence is found to be the most critical parameter to produce high quality of precursor perovskite Nd 0.8 Sr 0.2 NiO 3 phase. In contrast, high quality of Nd 0.8 Sr 0.2 NiO 3 phase can be achieved with large range of growth temperature and oxygen partial pressure. [ABSTRACT FROM AUTHOR]

• The spinel-structured CoCrOx (1:2) loaded on N-doped carbon (CoCrOx (1:2)-CN) was prepared. • CoCrOx (1:2)-CN catalyst showed high activity and selectivity to CTH of cinnamaldehyde. • Through interfacial electron migration and N-doped carbon, the acidity and basicity of mesoporous catalyst were enhanced, thereby achieving optimal acid-base synergy. • The spinel structure and N-doped carbon can serve to reduce the reaction activation energy and reaction energy barrier. We present a simple catalyst preparation route, that is spinel-structured CoCrOx (1:2) loaded on N-doped carbon (CoCrOx (1:2)-CN). The as-synthesized CoCrOx (1:2)-CN catalyst promoted catalytic hydrogen transfer (CTH) of cinnamaldehyde (CMA), affording cinnamyl alcohol (CMO) yield as high as 95.3% under mild reaction conditions. There are several reasons for the high yield of CMA: (a) Through interfacial electron migration and N-doped carbon, the acidity and basicity of mesoporous CoCrOx (1:2)-CN catalyst were enhanced, thereby achieving optimal acid-base synergy. (b) Kinetic studies indicated that spinel-structure and N-doped carbon could increase the reaction rate and achieve a low activation energy (69.2 kJ/mol). (c) DFT calculations revealed that both pyridyl-N and pyrrolyl-N doping lowered the energy barrier for adsorption and desorption of reactants resulting in improved catalytic activity. In addition, the CoCrOx (1:2)-CN catalyst showed good reusability. The spinel structure oxide CoCr 2 O 4 supported by N-doped carbon (CoCrOx (1:2)-CN) was prepared and showed high activity and selectivity to CTH of cinnamaldehyde. The preparation of catalyst was simple and convenitent, and the CMO yield and selectivity of the CoCrOx (1:2)-CN catalyst could reach 95.3% and 97.7%, respectively. Through catalyst characterization, kinetic studies and DFT calculations, it was found that N-doped carbon can increase the acidity and basicity of catalyst and serve to reduce the reaction activation energy and reaction energy barrier, which is a significant improvement of catalytic activity. In addition, the catalyst exhibited remarkable reusability. [Display omitted] [ABSTRACT FROM AUTHOR]

• Use the human eye to locate ROI to solve the problem of lacking face information. • Filter outliers based on residual network to improve the consistency of HR estimation. • Use the rectangle to mask face video and generate mask dataset. Remote photoplethysmography (rPPG), which aims at measuring heart activities without any contact, has great potential in many applications. The emergence of novel coronavirus pneumonia COVID-19 has attracted worldwide attentions. Contact photoplethysmography (cPPG) methods need to contact the detection equipment with the patient, which may accelerate the spread of the epidemic. In the future, the non-contact heart rate detection will be an urgent need. However, existing heart rate measuring methods from facial videos are vulnerable to the less-constrained scenarios (e.g., with head movement and wearing a mask). In this paper, we proposed a method of heart rate detection based on eye location of region of interest (ROI) to solve the problem of missing information when wearing masks. Besides, a model to filter outliers based on residual network was conceived first by us and the better heart rate measurement accuracy was generated. To validate our method, we also created a mask dataset. The results demonstrated that after using our method for correcting the heart rate (HR) value measured with the traditional method, the accuracy reaches 4.65 bpm, which is 0.42 bpm higher than that without correction. [ABSTRACT FROM AUTHOR]

Abstract: Adenosine 5′-monophosphate-activated protein kinase (AMPK) has been demonstrated as a promising drug target due to its regulatory function in glucose and lipid metabolism. 20(S)-protopanoxadiol (PPD) was firstly identified from high throughput screening as a small molecule activator of AMPK subtype α2β1γ1. In order to enhance its potency on AMPK, a series of PPD derivatives were synthesized and evaluated. Structure–activity relationship study showed that the amine derivatives at the 24-position (groups I–VI) can improve the potency (EC50: 0.7–2.3 μM) and efficacy (fold: 2.5–3.8). Among them, compounds 12 and 13 exhibited the best potency (EC50: 1.2 and 0.7 μM) and efficacy (fold: 3.7 and 3.8). Further study suggested the mechanism of AMPK activation may functioned at the allosteric position, resulting the inhibition of the lipid synthesis in HepG2 cell model. [Copyright &y& Elsevier]

Abstract: Novel 20(S)-protopanoxadiol (PPD) analogues were designed, synthesized, and evaluated for the chemosensitizing activity against a multidrug resistant (MDR) cell line (KBvcr) overexpressing P-glycoprotein (P-gp). Structure–activity relationship analysis showed that aromatic substituted aliphatic amine at the 24-positions (groups V) effectively and significantly sensitized P-gp overexpressing multidrug resistant (MDR) cells to anticancer drugs, such as docetaxel (DOC), vincristine (VCR), and adriamycin (ADM). PPD derivatives 12 and 18 showed 1.3–2.6 times more effective reversal ability than verapamil (VER) for DOC and VCR. Importantly, no cytotoxicity was observed by the active PPD analogues (5μM) against both non-MDR and MDR cells, suggesting that PPD analogues serve as novel lead compounds toward a potent and safe resistance modulator. Moreover, a preliminary mechanism study demonstrated that the chemosensitizing activity of PPD analogues results from inhibition of P-glycoprotein (P-gp) overexpressed in MDR cancer cells. [Copyright &y& Elsevier]

Abstract: The interactions between an electrochemically fabricated Ag quantum wire and NH3 molecules in an aqueous environment were studied. The Ag quantum wire showed a stepwise decrease of conductance change upon exposure to the definite concentration of NH3 molecules in an aqueous environment. Similar changes were also observed when an Ag quantum wire interacted with methyl amine, ethylenediamine and acetonitrile molecules, respectively. We experimentally probed the mechanism for the conductance modulation in the case of ammonia and proposed a model to describe it. The Ag quantum wire showed a conductance increasing process upon addition of the chemical reduced regent, sodium borohydride or ascorbic acid. Conductance increase was also seen with a process of electrochemical reduction. Based on the related data, we further proposed the existing partly Ag ions in the Ag quantum wire surface played a key role for these changes of Ag wire conductance. The work also showed the unique property of atomic-scale metal electrode different from the bulk electrode. [Copyright &y& Elsevier]

Abstract: Follistatin-like 1 (Fstl1), also named TSC-36 (TGF-β-stimulated clone 36), was first cloned from the mouse osteoblastic MC3T3-E1 cell line and can be up-regulated by TGF-β. To better study the function of Fstl1 during the development of the mouse central nervous system (CNS), we examined Fstl1 expression in the developing mouse CNS, in detail, by in situ hybridization. Our results show that Fstl1 is strongly expressed in the telencephalon, diencephalon, brainstem, limbic system and spinal cord. In the telencephalon, Fstl1 positive cells are mainly located in the ventricular zone (VZ) and the subventricular zone (SVZ); a relatively weak signal was observed in layers II and III of the neocortex at postnatal stages. Fstl1 expression is robust in the developing hippocampus and persists to P20. In the developing diencephalon and hindbrain, abundant Fstl1 signals were also detected in nuclei including the medial habenular nucleus, the medial dorsal nucleus, the cochlear nuclei and so on. In addition, a strong expression of Fstl1 was detected in the thalamencephalic signal center, as well as in the olfactory cortex from E14.5 to P0. Meanwhile, Fstl1 was expressed in the septal area and the cingulate gyrus of the limbic system after birth. A high level of expression was also observed in the ventral horn of the spinal cord. These results indicate that Fstl1 may play an important role during CNS development in the mouse. [Copyright &y& Elsevier]

Abstract: Noxious peripheral stimuli are detected by nociceptive DRG sensory neurons; this information is transmitted to the superficial dorsal horn of the spinal cord, relayed to the brain, then perceived as pain. Previous studies have shown that Wnt signaling plays a crucial role during the development of nociceptive circuits. We have reported a transgenic mouse line in which Tau-LacZ is driven by the promoter of one Wnt receptor, Frizzled10. Here, we further characterize this transgenic mouse line and present our findings that nociceptive circuits were specifically labeled by the Tau-LacZ transgene in developing spinal cord and DRG. Tau-LacZ specifically labeled commissural axons crossing the floor plate and transmitting nociceptive information to the brain. Thus this mouse line will provide a powerful genetic tool for studying the development of spinal nociceptive circuits and the mechanisms of commissural axon guidance. [Copyright &y& Elsevier]

Green evolution of enterprises is a significant way to realize society's sustainable development. Although this concept is generally accepted, the attitude of stakeholders is not positive. For example, some countries have different views on the question of whether to adopt relevant policies in order to promote the green evolution of enterprises. In this study, this issue is described as an exploration of the differences between free-market competition and policy intervention. In addition, a life cycle model of competition between green and non-green products is constructed by drawing upon game theory and Hotelling's model. This study provides reasonable suggestions for relevant policy formulation. The results show that, first, policy interventions help accelerate the green evolution of firms, but consumers bear the necessary costs. Second, green firms have advantages in terms of price, sales volume, and revenue under policy intervention, when compared with non-green firms, which have disadvantages that are more significant under policy intervention. In addition, free-market competition can create more cumulative profits at the expense of the time for firms to evolve green. Finally, a decision-targeting mechanism is designed on the basis of governmental balance of payments that considers the policy-planning period and provides specific decision-making references for policymakers. [ABSTRACT FROM AUTHOR]

Abstract: With oxygen that was supplied by hydrogen peroxide as oxidant, secondary and primary aliphatic alcohols, primary allylic alcohols could be efficiently oxidized to aldehydes or ketones in high yields in the presence of Pd (OAc)2−sodium oxalate (SO) under solvent-free conditions, it is a high yielding and operationally simple method. Acetic acid is testified to attend the reaction, the acetate ligands are environed to serve two purposes: as a ligand for the PdII center and as a base to deprotonate the Pd-bound alcohol, but acetic acid has not shown in previous bidentate ligands systems, so a mechanism is proposed on the basis of the mechanisms reported by the pioneers. [Copyright &y& Elsevier]

Abstract: Semiconductor gas sensors are wildly applied in gas identification and temperature-modulated dynamic test method is frequently used to improve sensors’ selectivity and stability. This paper introduces a new strategy combing wavelet decomposition and a distributed support vector machine network to identify gas mixtures. In a previous study concerning identifying gases of a few types, we had demonstrated that wavelet decomposition outperforms FFT in feature extraction from responses of thermally modulated semiconductor gas sensors. Here, we extend this method of recognizing gas mixtures of a large type and generalize the rules of selecting the character variables from decomposed wavelet coefficients as character variables. Besides, a distributed support vector machine network is introduced to discriminate the character variables into gas patterns instead of traditional BP neural network. Experiment results show that the strategy proposed here can perform accurate discrimination between hydrogen (H2), carbon monoxide (CO), ethane (C2H4) and their mixtures (total seven patterns) over a range of 50–1000ppm, by using only one commercial metal oxide semiconductor gas sensor, and the discrimination result has advantages in restraining gas concentration variation, sensor''s drift and environmental changes. Experimental result also suggests that a distributed support vector machine outperforms a single support vector machine and a BP neural network in performing gas mixture identification. [Copyright &y& Elsevier]

Catalytic transfer hydrogenation (CTH) reaction is an effective method for the preparation of biomass value-added chemicals. Herein, we propose a simple preparation route that converts biomass-derived furfural (FUR) to furfuryl alcohol (FOL) over a series of Ni-Mg-Al catalysts (NMA) with different molar ratios. When the Ni/Mg/Al molar ratio is 5:3:2 (expressed as NMA-2), the best furfuryl alcohol yield can be obtained. The multi-center synergy of the optimal acid-base ratio and metal sites, mesoporous structure and the highest O defect /O lattice ratio can be attributed to the main reason for the highest catalytic activity of the NMA-2 catalyst. Meanwhile, the reaction kinetics are discussed, and a possible reaction mechanism is proposed. [Display omitted] • This work can effectively catalyze the conversion of furfural into furfuryl alcohol. • Optimal acid-base ratio (0.73:1) and metal sites (Ni) achieve multi-center collaborative catalysis. • Mesoporous structure and the highest O defect /O lattice ratio create more adsorption sites and improve catalytic activity. • Through kinetic studies, this excellent catalytic performance is related to low activation energy. We propose a simple preparation route that converting biomass-derived furfural (FUR) to furfuryl alcohol (FOL) over a series of Ni-Mg-Al catalysts (NMA-n) with different molar ratios. Yield of FOL can reach 96.8 % over NMA-2 catalyst under the mild reaction conditions. There are three reasons for this high yield of FOL: (1) The introduction of different amounts of Mg and Al causes the synergistic effect to adjust the acidity and basicity of catalyst, optimal acid-base ratio (0.73:1) and Ni metal site achieve multi-centers collaborative catalysis. (2) Mesoporous structure of this catalyst provides a large number of adsorption sites. Furthermore, the highest O defect /O lattice ratio (1.79:1) create more oxygen vacancies, and then increase the adsorption sites of reactants, thereby making the catalytic activity of NMA-2 higher than most reported Ni-based catalysts. (3) Through kinetic studies, this excellent catalytic performance is related to activation energy (51.8 kJ/mol), which is lower than most reported CTH catalysts. [ABSTRACT FROM AUTHOR]

• Metagenomics revealed high-concentrate (HC) diets altered rumen microbial composition. • The rumen microbial changes under HC diets altered the microbial functions. • HC diets increased the abundance of carbohydrate-active enzymes related to starch degradation. • HC diets increased the abundance of genes encoding key enzymes during the VFAs formation. Although numerous studies have revealed the effects of high-concentrate (HC) diets on rumen microbial composition and metabolism, information regarding changes in the volatile fatty acids (VFAs) formation process under HC feeding is still limited. In the present study, we used a metagenomics approach to compare the effects of low-concentrate (LC) diets and high-concentrate (HC) diets on alterations to the rumen microbiota and their functions, particularly the functional genes involved in the metabolic routes of VFAs. The results showed that the HC diets increased (P < 0.05) the relative abundance of Eubacterium spp., Clostridium spp., Ruminococcus spp., Lactobacillus , and Bifidobacterium spp. and decreased (P < 0.05) the relative abundance of Prevotella spp., Fibrobacter succinogenes , and Bacteroides spp. The changes in rumen microbial composition further resulted in corresponding alterations in microbial function. Results regarding the carbohydrate-active enzymes revealed that the HC diets increased (P < 0.05) the abundance of glycoside hydrolases 13 (GH13; α-amylase activity), carbohydrate-binding module 26 (CBM26; starch-binding function), and CBM34 (starch-binding function) and simultaneously decreased (P < 0.05) the abundance of cellulases (GH5, GH9 and GH51). During the process of starch–pyruvate–VFAs, the HC diets increased (P < 0.05) the abundance of genes encoding pyruvate kinase (PK), pyruvate ferredoxin oxidoreductase (PFOR), and L-lactate dehydrogenase (LDH), which may be a reason behind the accumulation of rumen butyrate and propionate in the present study. Overall, these results clarified the mechanism behind how HC diets affect the formation process of rumen VFAs and provided new insight into the effect of HC diets on rumen microbiota. [ABSTRACT FROM AUTHOR]

Adenosine monophosphate-activated protein kinase (AMPK) has been considered as a promising drug target for its regulation in both glucose and lipid metabolism. Mogrol was originally identified from high throughput screening as a small molecule activator of AMPK subtype α2β1γ1. In order to enhance its potency on AMPK and summarize the structure-activity relationships, a series of mogrol derivatives were designed, synthesized and evaluated in pharmacological AMPK activation assays. The results showed that the amine derivatives at the 24-position can improve the potency. Among them, compounds 3 and 4 exhibited the best potency (EC 50 : 0.15 and 0.14 μM) which was 20 times more potent than mogrol (EC 50 : 3.0 μM). [ABSTRACT FROM AUTHOR]

Most β-galactosidases reported are sensitive to the end product (galactose), making it the rate-limiting component for the efficient degradation of lactose through the enzymatic route. Therefore, there is ongoing interest in searching for galactose-tolerant β-galactosidases. In the present study, the predicted galactose-binding residues of β-galactosidase from Bacillus coagulans , which were determined by molecular docking, were selected for alanine substitution. The asparagine residue at position 148 (N148) is correlated with the reduction of galactose inhibition. Saturation mutations revealed that the N148C, N148D, N148S, and N148G mutants exhibited weaker galactose inhibition effects. The N148D mutant was used for lactose hydrolysis and exhibited a higher hydrolytic rate. Molecular dynamics revealed that the root mean square deviation and gyration radius of the N148D-galactose complex were higher than those of wild-type enzyme-galactose complex. In addition, the N148D mutant had a higher absolute binding free-energy value. All these factors may lead to a lower affinity between galactose and the mutant enzyme. The use of mutant enzyme may have potential value in lactose hydrolysis. [Display omitted] [ABSTRACT FROM AUTHOR]

Most existing dominance relations give higher priority to convergence than diversity and cannot offer reasonable selection pressure according to the evolution status. This easily makes the population converge to a sub-region of the Pareto front, and further leads to the imbalance between the convergence and diversity of population. To address the problem, we propose a dual distance dominance based evolutionary algorithm with selection-replacement operator for many-objective optimization (3DEA). In 3DEA, a dual distance dominance is proposed to strike a good balance between the convergence and diversity of population, where the dual distance is designed to measure the convergence of individuals and can adapt to different Pareto fronts. This dominance relation also combines the angle based niche to emphasize the diversity of individuals, in which the niche size is dynamically adjusted according to the number of objectives and evolution status. Meanwhile, a selection-replacement operator is developed to further maintain the population diversity and contribute to the convergence. In addition, a special points guided classification mutation mechanism is designed to generate excellent individuals in sparse regions and regions close to the Pareto front, and further improve the search efficiency of 3DEA. To verify the performance of 3DEA, we compare 3DEA with seven state-of-the-art methods on 30 test problems with the number of objectives varying from 5 to 20 and three practical applications. Experimental results demonstrate the proposed 3DEA has higher competitiveness on most test problems compared with seven state-of-the-art methods. • A dual distance-based dominance relation is proposed to drive the evolution. • A dual distance-based convergence measure is designed. • A selection-replacement operator is designed. • A special points guided classification mutation strategy is developed. [ABSTRACT FROM AUTHOR]

β-Galactosidase is one of the most important enzymes used in dairy industry. Here, a novel thermostable β-galactosidase was cloned and overexpressed from Bacillus coagulans NL01 in Escherichia coli. The phylogenetic trees were constructed using neighbor-joining methods. Phylogeny and amino acid analysis indicated that this enzyme belonged to family 42 of glycoside hydrolases. The optimal pH and temperature were, respectively, 6.0 and 55 to 60°C. The purified enzyme had a 3.5-h half-life at 60°C. Enzyme activity was enhanced by Mn2+. Compared with other β-galactosidases from glycoside hydrolase family 42, B. coagulans β-galactosidase exhibited excellent hydrolysis activity. The Michaelis constant (K m) and maximum rate of enzymatic reaction (V max) values for p -nitrophenyl-β- d- galactopyranoside and o -nitrophenyl-β- d -galactopyranoside were 1.06 m M , 19,383.60 U/mg, and 2.73 m M , 5,978.00 U/mg, respectively. More importantly, the enzyme showed lactose hydrolysis ability superior to that of the commercial enzyme. The specific enzyme activity for lactose was 27.18 U/mg. A total of 104.02 g/L lactose in whey was completely hydrolyzed in 3 h with addition of 2.38 mg of pure enzyme per gram of lactose. In view of the high price of commercial β-galactosidase, B. coagulans β-galactosidase could be a promising prototype for development of commercial enzymes aimed at lactose treatment in the dairy industry. [ABSTRACT FROM AUTHOR]

Limited concentrations of oxygen in constructed wetlands (CWs) have inhibited their ability to remove emerging organic contaminants (EOCs) at μg/L or ng/L levels. Manganese (Mn) oxides were proposed as a solution, as they are powerful oxidants with strong adsorptive capabilities. In the present study, triclosan (TCS) was selected as a typical EOC, and CW microcosms with Mn oxides (birnessite) coated sand (B-CWs) and without (C-CWs) were developed to test the removal capacities of TCS and common nutrients. We found that the addition of Mn oxides coated sand significantly improved removal efficiencies of TCS, NH 4 -N, COD, NO 3 -N and TP ( P  < 0.05). The average concentration of Mn(II) effluent was 0.036 mg L −1 , mostly lower than the drinking water limit. To gain insight into the mechanisms of pollution removal, Mn transformation, dissolved oxygen (DO) distribution, bacterial abundance, and microbial community composition were also investigated. Maximum Mn(II) was detected at 20 cm height of the B-CWs in anoxic zone. Although Mn-oxidizing bacteria existed in the layer of 30–50 cm with 10 3 –10 4  CFU g −1 dry substate, Mn oxides were only detected at height from 40 to 50 cm with rich oxygen in B-CW. The quantities of bacterial 16S rRNA, amoA , narG and nosZ were not significantly different between two systems ( P  > 0.05), while Illumina high-throughput sequencing analysis revealed that the abundance of denitrifying bacteria was significant higher in B-CWs, and the abundance of Gammaproteobacteria that have a recognized role in Mn transformation were significantly increased. The results indicated that Mn oxides could enhance TCS and common pollutants removal in both anoxic and aerobic areas through the recycling of Mn between Mn(II) and biogenic Mn oxides. [ABSTRACT FROM AUTHOR]

Background Increasing studies demonstrate that reduced expression of miR-34a is involved in the initiation and progression of cancers, and it has been characterized as a tumor suppressor in various types of cancers. In present study, we investigated the expression and role of miR-34a in esophageal cancer. Methods qRT-PCR assays were performed to analyze the expression of miR-34a in human esophageal cancer tissues and adjacent esophageal tissues. CCK8 assay, flow cytometry analysis and in vitro migration assays were performed to analyze the role of miR-34a in human esophageal cancer cell. MSP assay was performed to analyze the DNA methylation of the miR-34a promoter. Results The expression of miR-34a was down-regulated in human esophageal cancer tissues. miR-34a ectopic expression affected esophageal cancer cells survival, proliferation and capabilities of migration in vitro. p53 status was not correlated with miR-34a. Subsequently, aberrant DNA methylation of the miR-34a promoter was found in human esophageal cancer, and 5-AZA-dC inhibited DNA methylation of the miR-34a promoter. Conclusions our data showed that miR-34a acted as a tumor suppressor in human esophageal cancer. [ABSTRACT FROM AUTHOR]

Many-objective optimization problems (MaOPs) have attracted wide attention. However, most solving methods prioritize the convergence or take the convergence and diversity into account. This causes the difficulty in balancing convergence and diversity of the population still remains, especially for these problems with irregular Pareto fronts. To this end, we propose a many-objective evolutionary algorithm under diversity-first selection based framework (DSFMO), which first emphasizes the diversity and then considers the convergence. Thus, DSFMO can drive individuals to approach the Pareto front from various directions, and further achieve the balance between convergence and diversity of the population. In this framework, we first construct a candidate pool by selecting these individuals with small crowded degree (i.e., good diversity), in which the crowded degree is evaluated by the global diversity measure based on the objective transferring. Then, the individual in the constructed candidate pool that has the best convergence is selected to enter the next generation, where the convergence is evaluated by the conditional convergence measure that considers the importance of boundary individuals and evolution status. The above two steps are repeatedly executed until the next generation population is formed. In addition, a space projection assisted mating selection is developed to select high-quality parents for variation and further enhance the exploration and exploitation ability of DSFMO. Experiments on 88 test instances have shown that DSFMO can perform best on most test instances. In other words, DSFMO outperforms its seven competitors in balancing convergence and diversity of the population. • A diversity-first selection based framework is develop. • An objective transferring based global diversity measure is proposed. • A conditional convergence measure is designed. • A space projection assisted mating selection is proposed. [ABSTRACT FROM AUTHOR]

Series of Co(OH) 2 /Cr 2 O 3 catalysts before and after calcination (denoted as CoCrO x) were prepared and used for the selective oxidation of toluene using oxygen in the absence of solvent. Co(OH) 2 /Cr 2 O 3 catalyst before calcination has exhibited excellent catalytic activity for the oxidation of toluene, conversion of toluene reaches 37.8% and selectivity of benzoic acid is up to 94.4%. Interestingly, calcined catalyst CoCrO x mainly produces benzaldehyde, and the selectivity for benzaldehyde can be as high as 63.6% (conversion of toluene remains high at 14.5%). A series of characterizations including XRD, TEM, FT-IR, XPS, H 2 -TPR and CO 2 -TPD illustrate that calcination makes phase transformation occur and leads to the change of acid-basic sites and reactive oxygen species, which affect the activity and selectivity of toluene oxidation. After calcination，Co2+ migrates to vacant sub-surface position of surface oxygen (O sur) and remains on the surface. The formation of Co-Co bond widens defect area so that activated O sur induces oxidation of toluene, leading to an increase in the amount of adsorbed oxygen, which becomes the decisive factor for high selectivity of benzaldehyde. [Display omitted] • The catalysts before and after calcination showed high selectivity for benzoic acid and benzaldehyde, respecvitvly. • The interaction of Co and Cr species in Co(OH) 2 /Cr 2 O 3 promotes the production of lattice oxygen. • The strong basic sites provided by lattice oxygen is a determinant of the high selectivity of benzoic acid. • The formation of oxygen vacancies in calcined catalyst results in the migration and enhanced activity of oxygen species. [ABSTRACT FROM AUTHOR]

Abstract: Wnt inhibitor factor-1 (WIF-1) is an extracellular antagonist of Wnts secreted proteins. Here we describe the expression pattern of Wif1 throughout the development of the mouse central nervous system (CNS). Wif1 mRNA can be detected as early as the developmental stage E11, and expression persists to adulthood. In embryonic stages, the level of Wif1 expression was very prominent in several areas including the cerebral cortex, the diencephalon and the midbrain, with the strongest level in the hippocampal plate and the diencephalon. However, after birth, the expression level of Wif1 decreased in the cortex and diencephalon. By adulthood, Wif1 is mainly expressed in the medial habenular nucleus (MHb) in the epithalamus, the mitral layer cells in the olfactory bulb and a few nuclei in the hypothalamus. Our data shows that the expression of Wif1 was very strong during embryonic development of the CNS and suggests that Wif1 may play an essential role in the spatial and temporal regulation of Wnt signals. [Copyright &y& Elsevier]