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Nisin is a promising therapeutic candidate because of its potent activity against Gram-positive bacteria. The present study aimed to describe the in vitro and in vivo antibacterial effects of nisin against Streptococcus suis, an important zoonotic pathogen. The minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) of nisin against different S. suis strains ranged from 0.12 to 4.0 μg/mL and from 0.25 to 8.0 μg/mL, respectively. Time-killing curve assays illustrated that nisin killed 100% of tested virulent S. suis strains within 4 h when used at 2× MIC, which indicates the rapid bactericidal activity of nisin against the bacteria. Transmission and scanning electron microscopy revealed that nisin destroyed S. suis cell membrane integrity and affected its cellular ultrastructure, including a significantly wrinkled surface, intracellular content leakage, and cell lysis. In addition, nisin inhibited biofilm formation by S. suis in a concentration-dependent manner and exhibited strong degrading activities against preformed biofilms. More importantly, nisin displayed antimicrobial activity against S. suis infection in vivo. Upon treatment with 5.0-10 mg/kg nisin solution, the survival rates of mice challenged with a lethal dose of virulent S. suis virulent ranged 87.5-100%. Nisin significantly decreased bacterial proliferation and translocation in the mouse spleen, brain, and blood. These results indicate that nisin has potential as a novel antimicrobial agent for the clinical treatment and prevention of infection caused by S. suis in animals.

Overwintering is one of an important stage for aquatic animals, and light intensity has an important effect on the conservation of Scylla paramamosain during overwintering. Three different light intensity levels (0, 1.43 and 40.31 μmol m⁻² s⁻¹) were used to explore the effects of light intensity on digestion and immune responses, plasma cortisol and amino acid composition of S. paramamosain. This is the first report that the adult S. paramamosain can be effect by the light intensity. The results showed that S. paramamosain has a strong stress response under high light intensity. Compared with darkness condition, digestive enzyme activity was higher under light condition. S. paramamosain reared under low light conditions had enhanced immunity, and it raised in light conditions exhibited superior qualities to those cultured in dark conditions. The results of this study demonstrated that low light levels are most suitable for breeding and improving the quality of S. paramamosain.

This study was to explore the potential mechanism of naprapathy in treating neuropathic pain (NP) after brachial plexus injury (BPI).Totally 72 rats were randomly divided into normal group, model control group, and naprapathy group (n=24 per group). A right upper-limb chronic NP model was established, and naprapathy was administered at C5-T1 Jiaji Points on 4th day after modeling. Naprapathy was performed for 15 min once daily with a frequency of 60 per minute. The treatment was applied for altogether 28 days. Cold pain threshold and mechanical pain threshold were measured 1 day before modeling, 3 days after modeling, and 7, 14, 21 and 28 days after naprapathy; 7, 14, 21 and 28 days after naprapathy, rats were killed and the β-endorphin expression and γ-aminobutyric acid (GABA) content were detected in the thalamus.After 14-day treatment, there was significant difference of mechanical pain threshold between the naprapathy group and the normal group (P0.05); after treatment for 21 and 28 days, there was no significant difference between the naprapathy group and the normal group (P0.05); after 28-day naprapathy, there was significant difference of β-EP expression between the normal group and the naprapathy group (P0.05), while the difference between model control group and naprapathy group was statistically significant (P0.05). After 14-day treatment, there was significant difference of GABA content between the model control group and the naprapathy group (P0.05). After 28-day treatment, significant difference was also found between the model control group and the naprapathy group (P0.05).After naprapathy, chronic NP is attenuated in rats with BPI, which might be ascribed to the upregulation of β-endorphin and GABA.

Three salinities (4‰, 12‰ and 25‰) were selected to determine the effects of different salinities on the growth, survival, nutrition and energy metabolism of Scylla paramamosain during indoor overwintering. Growth performance (survival rate, condition factor, hepatopancreatic index, weight gain rate and specific growth rate), nutrient composition (ash, moisture, crude fat, crude protein and total nitrogen), fatty acids, energy metabolites (glycogen, glucose, triglycerides, cholesterol and lactic acid) and energy metabolic enzymes (hexokinase, pyruvate kinase, lactate dehydrogenase and succinate dehydrogenase) were measured and calculated. The results showed that S. paramamosain exhibited the best growth and survival at 25‰ and worst at 4‰ after overwintering. In addition to consuming crude fat, excess protein was also broken down to provide energy in the 4‰ and 12‰ groups. The content of unsaturated fatty acids in the 25‰ group was higher after overwintering. Glycogen and glucose consumption and triglycerides, cholesterol and lactic acid production were lowest in the 25‰ group. The activity of hexokinase, pyruvate kinase, lactate dehydrogenase and succinate dehydrogenase was highest in the 4‰ group and lowest in the 25‰ group. The activity of hexokinase, pyruvate kinase, lactate dehydrogenase and succinate dehydrogenase in the hepatopancreas was higher than in the muscle. In conclusion, S. paramamosain uses less energy, has more unsaturated fatty acids and has a higher survival rate at a salinity of 25‰ after overwintering. The results of this study provide helpful information the indoor overwintering S. paramamosain in aquaculture production systems.

Aims. The underlying mechanisms involved in Vitamin A- (VA-) related changes in glucose metabolic disorders remain unclear. Recent evidence suggests that intestinal microbiota is closely linked to the metabolic syndrome. Here, we explored whether and how intestinal microbiota affects glucose homeostasis in VA-deficient diet-fed mice. Methods. Six-week-old male C57BL/6 mice were randomly placed on either a VA-sufficient (VAS) or VA-deficient (VAD) diet for 10 weeks. Subsequently, a subclass of the VAD diet-fed mice was switched to a VA-deficient rescued (VADR) diet for an additional 8 weeks. The glucose metabolic phenotypes of the mice were assessed using glucose tolerance tests and immunohistochemistry staining. Changes in intestinal microbiota were assessed using 16S gene sequencing. The intestinal morphology, intestinal permeability, and inflammatory response activation signaling pathway were assessed using histological staining, western blots, quantitative-PCR, and enzyme-linked immunosorbent assays. Results. VAD diet-fed mice displayed reduction of tissue VA levels, increased area under the curve (AUC) of glucose challenge, reduced glucose-stimulated insulin secretion, and loss of β cell mass. Redundancy analysis showed intestinal microbiota diversity was significantly associated with AUC of glucose challenge and β cell mass. VAD diet-driven changes in intestinal microbiota followed the inflammatory response with increased intestinal permeability and higher mRNA expression of intestinal inflammatory cytokines through nuclear factor-κB signaling pathway activation. Reintroduction of dietary VA to VAD diet-fed mice restored tissue VA levels, endocrine hormone profiles, and inflammatory response, which are similar to those observed following VAS-controlled changes in intestinal microbiota. Conclusions. We found intestinal microbiota effect islet function via controlling intestinal inflammatory phenotype in VAD diet-fed mice. Intestinal microbiota influences could be considered as an additional mechanism for the effect of endocrine function in a VAD diet-driven mouse model.

Background: Vitamin A (VA) plays an essential role in pancreatic homeostasis. Islet stellate cells (ISCs) are VA-storing cells in pancreatic islets. Herein, we have investigated the effect of VA on glucose homeostasis trough regulation of ISCs function in dietary VA deficiency model mice. Methods: Male C57BL/6 mice were randomly fed a VA-sufficient, a VA-deficient (VAD) or a VAD-rescued diet. Glucose metabolism was assessed by glucose tolerance tests and immunohistochemistry. ISCs activation degree was evaluated by immunofluorescence, quantitative PCR and western blotting in both, retinol-treated cultured ISCs and model mice. Changes in ISCs phenotype and their effect on islets were assessed by lentiviral transduction and enzyme-linked immunosorbent assays in a co-culture system. Results: VAD mice showed irregular shaped islet, glucose intolerance, islet size distribution excursions, and upregulated expression of α-smooth muscle actin (α-SMA, marker of ISCs activation). Reintroduction of dietary VA restored pancreatic VA levels, endocrine hormone profiles, and inhibited ISCs activation. Incubation with retinol increased the expression of VA signaling factors in ISCs, including cellular retinol binding protein 1 (CRBP1). The knockdown of CRBP1 maintained the quiescent ISCs phenotype and reduced the damage of activated ISCs on islet function. Conclusions: VA deficiency reduced islet function by activating ISCs in VAD mice. Restoring ISCs quiescence via CRBP1 inhibition could reverse the impairment of islet function caused by activated ISCs exposure.

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In this paper, based on the coupling calculation of Simulink software and GT-Power software, an Optimizer model method was proposed for a 16V265H diesel engine to study the effects of different ratios of biodiesel (B0, B10, and B20) on the performance of a 16V265H diesel engine at 1000 rpm and 75% load. Firstly, the four parameters of diesel engine power, BSFC, soot emission, and NOx emission were taken as the result variables of the optimization model. Taking the intake and exhaust timing of the diesel engine as the independent variable of the optimization model, the maximum power, minimum BSFC, and minimum diesel engine emission were studied and analyzed. Finally, the performance parameters were comprehensively analyzed to determine the best intake and exhaust valve timing. Moreover, based on the model optimization, the diesel engine’s BSFC and power performance were compared, and the optimal intake timing scheme for the diesel engine with different biodiesel ratios at 75% operating conditions was obtained. The results showed that the maximum power, optimum BSFC, and minimum emissions of the 16V265H diesel engine with different ratios of biodiesel and different intake valve timing angles were also different. Under 75% load conditions, the BSFC reduction rate was up to 6.32%, and the power increase rate was up to 5.87%. In addition, by optimizing the model with B10 biodiesel and the intake valve timing close to 202°CA and the exhaust valve timing close to 98°CA, the diesel engine had the lowest NOx emission; with B10 biodiesel and the intake timing at 180°CA, the diesel engine had the lowest BSFC; and with B10 biodiesel and the intake valve timing close to 179.5°CA, the diesel engine had the maximum power. In conclusion, the diesel engine is best with B10 biodiesel. This research method can provide a reference for implementing variable intake system technology for the 16V265H diesel engine.

Escherichia coli O157:H7 is a pathogen that commonly causes foodborne illness and represents a health hazard to consumers. The combined use of synergistic antimicrobial peptides (AMPs) is a promising way to improve the microbiological safety of foods. In this study, we detected the synergistic interactions between thanatin and BF-15a3 to reduce their usage and obtain more efficient antibacterial activity. The minimal inhibitory concentrations (MICs) of thanatin and BF-15a3 against 49 E. coli O157:H7 strains were ranged from 2 to 8 μg/mL and 4-32 μg/mL, showed a general inhibitory effect on E. coli O157:H7 strains, respectively, even multidrug-resistant strains. Their fractional inhibitory concentration index (FICI) was 0.375, which suggested that their combination presented synergistic antibacterial effect against E. coli O157:H7. The killing kinetic curves indicated that the 0.25 × MIC combination had equivalent bactericidal effects to 1 × MIC thanatin or BF-15a3. When AMP combinations were used to treat eukaryotic cells to evaluate the hemolytic characteristics against rabbit erythrocytes and cytotoxicity against human embryonic kidney 293T (HEK-293T) cells and intestinal porcine enterocyte J2 (IPEC-J2) cells, no magnified adverse effects were observed, exhibiting higher specificity to bacteria and lower toxicity to eukaryotic cells. Compared with bacteriostasis of thanatin or BF-15a3 alone, the proportion of membrane-damaged bacteria treated with the synergetic combination did not appear a significant rise, interestingly the Zeta potential of them greatly decreased and their cell membrane permeability significantly increased. Besides, more release of ions and cytoplasm were detected, confirming a more severe loss of membrane integrity. These results suggested that the synergistic action mode of thanatin and BF-15a3 is likely attributed to damage aggravation to E. coli membrane. When applying in fresh-cut lettuce and cucumber, their combination allowed for 2.5 log CFU/piece reductions of E. coli O157:H7 in 24 h. In conclusion, the combination of thanatin and BF-15a3 showed excellent synthetic efficacy to kill E. coli O157:H7 in vitro under lower MICs than single use of them.

AimsWe evaluated the efficacy and significant changes in the levels of retinol-binding protein 4 (RBP-4) and insulin resistance in patients with type 2 diabetes mellitus (T2DM) treated with chiglitazar versus sitagliptin.MethodsEighty-one T2DM patients with haemoglobin A1c (HbA1c) level of 7.5%–10.0% were selected. Based on the study criteria, patients were randomly assigned to receive chiglitazar (32 mg), chiglitazar (48 mg), or sitagliptin (100 mg) orally for 24 weeks. Sociodemographic and anthropometric characteristics, lipid profiles, glucose profiles, and serum RBP-4 levels were determined at baseline and at the end of the therapy.ResultsAfter treatment for 24 weeks, significant changes in fasting blood glucose (FBG), fasting insulin (Fins), 2 h-blood glucose (2h-BG), the score values of insulin resistance/insulin secretion/β cell function (HOMA-IR, HOMA-IS, and HOMA-β), triglyceride (TG), free fatty acid (FFA), high-density lipoprotein cholesterol (HDL-C), and RBP-4 levels were detected in patients with chiglitazar administration and sitagliptin administration. Changes in RBP-4 levels were positively correlated with changes in HOMA-IR and 2 h-BG in linear regression.ConclusionsChiglitazar showed a greater improvement in parameters of diabetes than sitagliptin, and changes in serum RBP-4 levels were associated with changes in insulin-sensitizing parameters.Clinical Trial RegistrationClinicalTrials.gov, CT.gov identifier: NCT02173457.

The global marine biogeochemical cycle of aluminum (Al) is believed to be driven by marine diatoms, due to the uptake of dissolved Al (DAl) by living diatoms from surface seawater. The occurrence of Al in diatom biogenic silica (BSi) can inhibit the dissolution of BSi, thus benefiting the effects of the ballast role of diatoms in the biological pump and forming a coupled Si-Al biogeochemical cycle. However, the occurrence mechanism of Al in marine diatoms is still unclear. In particular, whether or not Al is incorporated into the structure of BSi of living diatoms is unrevealed, resulting in difficulties in understanding the biogeochemical behaviors of Al. In this study, Thalassiosira weissflogii, a widely distributed marine diatom in marginal seas, was selected as the model to evaluate the occurrence of structural Al in BSi based on culturing experiments with the addition of DAl. The structural Al in BSi was detected by combining focused ion beam (FIB) scanning electron microscopy and energy dispersive X-ray spectroscopy (EDS) mapping analysis. Direct evidence of structural Al in living BSi was obtained for the first time. The distribution and content of this Al were revealed by the EDS-mapping analysis. The structural Al in the BSi exhibited a homogeneous distribution, and the average Al / Si atomic ratio obtained through the FIB-EDS mapping analysis was 0.011. The effects of structural Al on BSi dissolution-inhibition are discussed based on the content of this Al. The fundamental results indicate the significant contribution of marine diatoms to the biogeochemical migration of marine Al.

In this work, Al2O3–MnO2@diatomite composite (AM-Dt) was prepared by a simple hydrothermal method. This composite was formed by using diatomite as a porous substrate to support Al2O3 and MnO2 nanop...

The occurrence of minor elements in the structure of biogenic diatomaceous opal-A is an important issue because it is closely related to biogeochemical processes driven by the precipitation, sedimentation, and storage of diatoms, as well as to the properties and applications of diatomite, which is the sedimentary rock composed of diatomaceous opal-A. However, to date, there is no direct microscopic evidence for the existence of minor elements, such as Al, Fe, and Mg, in the structure of diatomaceous opal-A, because such evidence requires observation of the internal structure of frustules to exclude the disturbance of impurity minerals, which is technically challenging using conventional techniques. In this work, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDS) mapping analysis were performed on diatomaceous opal-A from three typical diatomite specimens that were pretreated using focused ion beam (FIB) thinning. This technique produces a slice of a diatom frustule for direct TEM observation of the internal structure of the diatomaceous opal-A. The results of this work clearly indicate that minor elements, such as Al, Fe, Ca, and Mg, conclusively exist within the siliceous framework of diatomaceous opal-A. The contents of these minor elements are at atomic ratio levels of 1 (minor element)/10 000 (Si) – 1/100, regardless of the genus of the diatoms. The occurrence of minor elements in the internal structure is likely through biological uptake during biosynthesis by living diatoms. Moreover, surface coatings composed of aluminosilicates on diatom frustules are common, and the contents of elements such as Al and Fe are tens or hundreds of times higher in the coatings than in the internal siliceous structure of diatomaceous opal-A. The discovery of the incorporation of the above-mentioned minor elements in the diatomaceous opal-A structure, both in the internal Si-O framework and on the surface, updates the knowledge about the properties of diatomite.

Electrodialysis (ED) is an alternative to the conventional thermal regeneration of high-salt solutions used in air conditioning systems (ACSs). In this work, a simplified mathematical model was developed to describe the solute and water transport. The solute hydration number and free water content were proposed to characterize the solute hydration properties. A laboratory-scale ED regeneration system was set up to investigate the regeneration performance of three kinds of high-salt solutions (aqueous LiCl, LiBr and CaCl2 solutions) at various initial concentrations and current densities. The results demonstrate good agreement between numerical and experimental findings. The initial concentration and applied current density have great impacts on ED performance. Firstly, higher initial concentration generally results in lower membrane permselectivity, current efficiency, solute and water transfer rate, and higher energy consumption. Secondly, higher current density has a positive effect on solute and water transport but leads to more energy consumption. The solute hydration number and free water content both decrease with increasing initial concentration. The appropriate mass concentrations of 15%, 25% and 15% are respectively suggested for aqueous LiCl, LiBr and CaCl2 solutions when applying ED in ACSs to ensure responsible performance.

In order to solve the problem of poor regeneration performance of the solar solution dehumidification air conditioning regeneration system under high temperature and high humidity weather conditions. In this paper, a novel vacuum membrane distillation (VMD) solution regeneration method was proposed for a solution desiccant air conditioning system, and a theoretical study of this novel regenerator is performed. Through the analysis of heat and mass transfer, the mathematical model of VMD regeneration is established, and the mathematical model is verified by experiments. The results indicated that VMD regenerator not only could increase the regenerate rate but also could exhibit higher energy utilization efficiency. At the same concentration, the VMD regenerator has a higher regeneration performance, and the regeneration rate is 1.6–2.4 times that of the internal heat type regenerator, and the 4.5–6 times that of the adiabatic regenerator.

Transmission electron microscopy (TEM) is an essential and irreplaceable technique for studying the micromorphology and microstructure of clay minerals. However, observing layer stacking and detecting the interlayer spaces of clay minerals by TEM are still major challenges, due to the difficulty of finding suitable fields of view for clay planes along the [00l] direction. A simple and effective sample pretreatment method was proposed here for TEM characterization of clay mineral stacking structures and interlayer spaces. Using this method, clay mineral-bearing ultrathin slices, in which clay minerals particles showed an orientated arrangement, were prepared based on the resin embedding method. The (00l) plane of clay minerals was exposed toward electron beams during TEM analysis, and fields of view along the [00l] direction were observed, accordingly. This method is thus particularly useful for the observation of stacking information and detection of interlayer regions in clay minerals. The validity of this method is exemplified by its application to pure kaolinite and clay mineral-rich shale samples which contains several clay minerals and the clay mineral-organic matter complexes.

Allophane/diatomite (Allo/Dt) nanocomposite with a hierarchically porous structure was prepared via an in situ hydrothermal method. This hierarchically porous structure consists of i) micropores remaining from the initial stacked coating allophane particles; ii) mesopores formed by the transformation of the macropores of diatom frustules due to the filling of allophane particles in the inner walls, and iii) preserved macropores of diatom frustules. The coating amount of allophane particles in Allo/Dt nanocomposite was 59.1%, leading to a specific surface area of 155.9 m2/g, which was substantially higher than that of diatomite (17.9 m2/g). The benzene adsorption performance and related adsorption mechanisms of Allo/Dt nanocomposite were investigated. The larger benzene dynamic adsorption capacity of 121.6 mg/g, compared to that of the synthetic allophane (105.9 mg/g), resulted from the adequate adsorption space provided by the hierarchically porous structure. Moreover, Allo/Dt nanocomposite displayed a higher efficiency for benzene adsorption in mesopores of the coating allophane particles because of their improved dispersity. These results demonstrated that the fabrication process of Allo/Dt nanocomposite can overcome not only the aggregation of allophane but also diatomite's shortcoming of low specific surface area, making the nanocomposite to be a promising adsorbent for the treatment of volatile organic compounds.

Frost build-up on the fins of the evaporator severely decreases heat transfer and subsequently reduces the performance of the heat pump system. In this paper, a novel frost-free air source heat pump system is proposed, which combines with liquid desiccant dehumidification and closed-circuit regeneration. A test setup for investigating the performance of the proposed system and the corresponding performance indexes are developed to evaluate the system performance under variable working conditions. The effects of key parameters including solution temperature, solution concentration, air flow rate and solution flow rate on the regeneration performance and heating performance of the system are analyzed experimentally. Results show that the optimal mass flow rate ratio of the solution to the air is 1.4 in the regeneration mode, while the ratio of 0.55 is recommended in the heating mode. Additionally, performance comparison between the proposed system and the conventional reverse-cycle defrosting system available in the literature is conducted. It is concluded that the proposed system is superior to the reverse-cycle defrosting system when the ambient temperature is less than 0 °C and the relative humidity is higher than 65%.

Background: African Swine Fever Virus (ASFV) has been identified as the agent of ASF, which has resulting in a mortality rate of nearly 100% in domestic pigs worldwide. Protein p22 encoded by pKP177L was reported to be localized at the inner envelope of the virus, while the function of p22 remains unclear.Methods: Protein p22 interacted proteins of the host were immune-precipitated and identified by Liquid Chromatography Mass Spectrometry, analyzed by Go terms and KEGG pathways. Results: Numerous cellular proteins in 293-T that interacted with p22 protein were identified. These interacted proteins were related to the biological processes of binding, cell structure, signal transduction, cell adhesion, etc., and their interactions. At the same time, the interacted proteins participated in several KEGG pathways like ribosome, splicesome, etc. The key proteins in PPI network were closely related to actin filament organization and movement, resulting in affecting the process of phagocytosis and endocytosis. Conclusions: The identified high number of proteins interacted with p22 and as a large database should be very useful to elucidate the function of p22 in the near future, and lay the foundation for elucidating the mechanism of ASFV.

Background Scylla paramamosain is one of the commercially crucial marine crustaceans belonging to the genus Scylla, which is commonly distributed along the coasts of China, Vietnam, and Japan. Genomic and transcriptomic data are scarce for the mud crab. Light intensity is one of the ecological factors that affect S. paramamosain during indoor overwintering. To understand the energy metabolism mechanism adapted to light intensity, we analyzed the transcriptome of S. paramamosain hepatopancreas in response to different light intensities (0, 1.43, 40.31 μmol·m− 2·s− 1). Results A total of 5052 differentially expressed genes were identified in low light group (LL group, 3104 genes were up-regulated and 1948 genes were down-regulated). A total of 7403 differentially expressed genes were identified in high light group (HL group, 5262 genes were up-regulated and 2141 genes were down-regulated). S. paramamosain adapts to different light intensity environments through the regulation of amino acids, fatty acids, carbon and energy metabolism. Different light intensities had a strong impact on the energy generation of S. paramamosain by influencing oxygen consumption rate, aerobic respiration, glycolysis/gluconeogenesis pathway, the citrate cycle (TCA cycle) and fatty acid degradation. Conclusion Low light is more conducive to the survival of S. paramamosain, which needs to produce and consume relatively less energy to sustain physiological activities. In contrast, S. paramamosain produced more energy to adapt to the pressure of high light intensities. The findings of the study add to the knowledge of regulatory mechanisms related to S. paramamosain metabolism under different light intensities.

A long-term experiment was carried out to explore the effects of light intensity on growth performance, biochemical composition, fatty acid composition and energy metabolism of Scylla paramamosain. S. paramamosain were cultured under three illumination levels (0, 1.43 and 40.31 μmol m−2 s−1) in a recirculating water system of crab compartments for four months. S. paramamosain were fed to satiation once daily (17:00). The photoperiod was set at 10 L: 14 D (07:00–17:00). Results showed that the best growth of S. paramamosain was observed at the 1.43 μmol m−2 s−1 light intensity. The amount of energy substances was higher at the 1.43 μmol m−2 s−1 and 40.31 μmol m−2 s−1 light intensities. The amount of total unsaturated fatty acids (∑UFA) and total polyunsaturated fatty acids (∑PUFA) was significantly higher at the 1.43 μmol m−2 s−1 and 40.31 μmol m−2 s−1 light intensities (p < 0.05). However, total saturated fatty acids (∑SFA) were significantly higher at 0 μmol m−2 s−1 (p < 0.05). The concentrations of hepatic glycogen, blood glucose (GLU), total cholesterol (T-CHO) and triglyceride (TG) were significantly elevated at the 1.43 μmol m−2 s−1 light intensity, whereas the highest concentrations of muscle glycogen and lactic acid (LD) were at the 40.31 μmol m−2 s−1 light intensity (p < 0.05). Activities of hexokinase (HK) and pyruvate kinase (PK) were markedly higher at the 40.31 μmol m−2 s−1 light intensity, while the highest lactic dehydrogenase (LDH) activity was observed at 0 μmol m−2 s−1 and at 1.43 μmol m−2 s−1 for succinate dehydrogenase (SDH) (p < 0.05). Compared with 0 μmol m−2 s−1 and 40.31 μmol m−2 s−1, 1.43 μmol m−2 s−1 was more suitable for the breeding of S. paramamosain.

Vitamin A (VA), which is stored in several forms in most tissues, is required to maintain metabolite homeostasis and other processes, including the visual cycle, energy balance, epithelial cell integrity, and infection resistance. In recent years, VA molecules, also known as retinoids, have been extensively explored and used in the treatment of skin disorders and immune-related tumors. To date, several observational and interventional studies have explored the relationship between VA status and the pathogenesis of diabetes. In particular, VA micronutrients have been shown to regulate pancreatic development, β-cell function, pancreatic innate immune responses, and pancreatic stellate cells phenotypes through multiple mechanisms. However, there are still many problems to be proven or resolved. In this review, we summarize and discuss recent and available evidence on VA biological metabolism in the pancreas. Analysis of the effects of VA on metabolism in the pancreas will contribute to our understanding of the supportive physiological roles of VA in pancreas protection.

Light intensity is one of the ecological factors that appreciably affects the metabolism of Scylla paramamosain during overwintering. This study adopted the isobaric tag for relative and absolute quantitation (iTRAQ) method to investigate metabolic changes of S. paramamosain under three illumination levels (0, 1.43 and 40.31 μmol m−2·s−1) for four months during indoor overwintering. The iTRAQ identified 3282 proteins, among which 267 exhibited significant differential expression (122 upregulated and 145 downregulated) in the low light group, and 299 with significant differential expression (252 upregulated and 47 downregulated) in the high light group. Analysis of these results showed that there were different metabolic regulatory patterns under different light intensities. Low light is more conducive to the survival of S. paramamosain, which needs to produce and consume relatively less energy to sustain physiological activities. Thus, the essential proteins associated with physiological activities were significantly upregulated, while those related to energy production were significantly downregulated. In contrast, high light exerts a certain stress on the survival of S. paramamosain and required more energy to cope with this stress, which forced a significant upregulation of proteins related to stress response and energy production. The findings of this study highlighted the metabolic regulatory mechanisms of S. paramamosain under different light intensities.

Additional file 1: Table S1. The gene-specific primers used in this study, Table S2. Result statistics of splicing, Table S3. Summary for transcriptome sequencing data generated from nine cDNA libraries, Table S4. Summary of annotated genes in different databases, Table S5. Statistical table of SSRs, Table S6. Sub categorization of the metabolism group, Figure S1. Distribution of FPKM value in each sample.

In this paper, the simulation model was established based on GT-Power software, and a scheme using the Miller cycle based on biodiesel was proposed. Taking diesel engine 16V265H as the research object, the accuracy of the simulation model was verified by experiments. Combined with the comparison of physical and chemical characteristics of biodiesel and the experimental analysis of biodiesel under three different combinations, it was concluded that low ratio biodiesel was the best choice to meet the power, economy, and emission performance of diesel. Through the simulation scheme of the two Miller cycles for pure diesel (B0) and biodiesel (B10) under different load conditions at 1000 rpm, the NOx emission performance of pure diesel in a Miller cycle was significantly improved. On this basis, the comprehensive performance of the two Miller cycles was compared with biodiesel. The results showed that both the Miller cycles could reduce NOx emission. Combined with other key performances of a diesel engine, the best scheme to improve the performance of the diesel engine was to burn B10 biodiesel and overlap angle the Miller cycle of the variable valve at 30 °CA. The scheme has guiding significance for the application of the 16V265H diesel engine.

Weathered crust elution-deposited rare earth (WED-RE) ores are important rare earth element (REE) resources around the world. In these ores, the REE are believed to mainly exist as exchangeable REE(III) ions on the surfaces of clay minerals, such as tubular halloysite and platy kaolinite. However, the mechanisms underlying the sorption and desorption of REE(III) ions on clay minerals in the environment of weathered crusts remain ambiguous. In this study, the sorption/desorption characteristics of Eu(III) ions onto halloysite and kaolinite were investigated. The results revealed that Eu(III) was adsorbed onto both clay minerals through inner-sphere complexation and outer-sphere complexation, where the former was the primary sorption mechanism. Halloysite displayed a higher sorption capacity for Eu(III) than kaolinite in a weakly acidic environment (pH 4–6). The desorption efficiency increased with the increasing concentration of NH4+ ions. When the NH4+ concentration was 0.002 mol/L, which is similar to the typical cation concentration of groundwater/rainwater, the amount and rate of Eu(III) desorption from halloysite were lower than those from kaolinite. The desorption of Eu(III) ions from the two clay minerals is proposed to be governed by the attraction between the outer-sphere complexes and clay minerals when the NH4+ concentration is 0.002 mol/L. Therefore, halloysite has a higher sorption capacity and stronger retention capacity for Eu(III) than kaolinite, which suggests that halloysite may play a greater role in REE(III) enrichment in WED-RE ores than kaolinite owing to the similar chemical properties of REE(III) ions. The fundamental results obtained in this study afford new insights into the migration of REE and the role of clay minerals in REE enrichment during ore formation.

This paper proposes a novel solar vacuum membrane distillation (VMD) regeneration for liquid desiccant air conditioning (LDAC) system, and establishes a mathematical model of the VMD regeneration process and traditional thermal (TH) regeneration process based on the heat and mass balance. The corresponding simulation model was established by using Matlab software, and the model was verified by previous experiments. The results show that: the model results are consistent with the previous experimental results, and the maximum error is less than 6%. Model simulations are carried out to study the regeneration performance under various operating parameters and climatic conditions, meanwhile the comparison the solar power consumption for regenerating one kilogram desiccant between the VMD regeneration and TH regeneration. Results demonstrate that when the air temperature is less than 32 °C, the humidity ratio is higher than 19 g/kg, and the air flow rate is less than 0.13 kg/s, the VMD regenerator solution regeneration effect is better than the conventional thermal regenerator. VMD regeneration is more suitable for solution regeneration in wet areas than TH regeneration. Furthermore, when the solution temperature is lower than 60 °C, VMD regeneration outlet concentration is higher than TH regeneration. VMD regeneration is more suitable for low-grade energy. Analyze the solar power consumption for regenerating one kilogram desiccant found that the VMD regeneration saves 10–37% energy than TH regeneration. Through economic analysis, it is found that the VMD regenerator can save 582.4 kWh of electricity per year compared to the TH regenerator. According to the cost recovery calculation formula, the cost recovery period can be calculated as 13.8 years.

Despite the focus of many studies on the preparation, characterization, and potential applications of solvent-free nanofluids based on diverse nanomaterials, fewer studies have focused on how to control the macroscopic liquid-like behaviour of solvent-free nanofluids. The present study prepared a halloysite-based solvent-free nanofluid and developed a facile method of tuning the fluidity of this nanofluid by preheating halloysite (Hal) at different temperatures. The effects of preheating on the structure and surface functional groups of halloysite and further on the fluidity of the obtained nanofluids were explored. Heating Hal at 110 °C resulted in little changes to its surface functional moieties, and the obtained nanofluid (Hal110-F) did not exhibit a markedly different fluidity compared with Hal-F at room temperature, though Hal-F and Hal110-F had different melting temperatures and exhibited different fluidities at a lower temperature. While for Hal heated at 700 °C, the corresponding nanofluid (Hal700-F) exhibited a lower fluidity than Hal-F and Hal110-F due to the remarkable calcination-induced changes in the species/amount of surface functional moieties of Hal700. This method for controlling the fluidity of the nanofluids via a facile core pretreatment was believed to be versatile for most, if not all, solvent-free nanofluids.

Clay minerals are the main carriers of rare earth elements (REE) in weathered crust elution-deposited rare earth (WED-RE) ores. The clay mineral-water interface reaction is among the most important interactions controlling the aggregation and transportation of REE(III) ions. Yet long-term experiments of interactions between REE(III) ions and clay minerals are scarce in the literature. Here, two typical clay minerals that commonly occur in WED-RE ores, namely tubular halloysite (7 A) and platy kaolinite, were immersed in a La solution for 3 consecutive years. The specimens' characteristics were systematically determined using X-ray diffraction (XRD), transmission electron microscope (TEM), infrared spectroscopy (IR), and X-ray photoelectron spectroscopy (XPS). The partial rehydration of tubular halloysite (7 A) was observed, with the resulting rehydrated halloysite characterized by lattice fringes having d(001)-values of ~1.000 and 0.830 nm, whose distribution features demonstrated that the partial rehydration happened initially at the outermost layers of the halloysite (7 A). By contrast, both the morphology and structure of kaolinite remained intact after its 3-year-long immersion in the La solution. For both immersed halloysite and kaolinite, the La existed as inner-sphere complexes, outer-sphere complexes, and hydroxide particles adsorbed on the surface of minerals. However, La(III) ions partially penetrated the interlayer of halloysite but did not enter that of kaolinite. Accordingly, the intercalation of La(III) in halloysite may facilitate the rehydration of halloysite (7 A). These experimental results provide novel insight into the conditions for rehydrating tubular halloysite (7 A), and indicate a new possible state of REE(III) in WED-RE ores, both of which help us to better understand the geochemical behavior of REE and clay minerals in WED-RE ores.

Clay minerals associated with microbial body and trace fossils in rocks deposited in shallow marine environments have importance in understanding microbial preservation. We show experimentally that the presence of suspended detrital clays in oceanic environments is a crucial control on the formation of co-aggregates between filamentous cyanobacteria and clay minerals and is thus important in the sedimentation and subsequent preservation of cyanobacteria. Strong cyanobacteria-clay co-aggregation occurs over short time periods (3–7 days) in the presence of 10 mg/L of suspended clay minerals (illite, kaolinite and montmorillonite), and the occurrence of co-aggregation is not affected by the type of clay minerals present. The cyanobacteria-clay co-aggregation shows a pronounced effect on preserving the biomass of cyanobacteria. The surface properties of clay minerals and cyanobacteria, specifically the electrostatic attraction between the oppositely charged surfaces of cyanobacteria and clay minerals, are the main drivers of cyanobacteria-clay co-aggregation. Chemical effects, such as the deprotonation of COOH groups in active organic compounds secreted by cyanobacteria and therefore the release of H+, result in local dissolution of clay and slight structure changes in the bulk of clay minerals. Compared with the suspended clay, dissolved ions (Si, Al or Fe ions) are of secondary importance in the formation of cyanobacteria-clay co-aggregates, although these ions further promote this process. Overall, the cyanobacteria-clay co-aggregation not only substantially affects the preservation of cyanobacteria, but also may have potentially important and profound impacts on related geochemical processes such as microbial dissolution of clay minerals and the biogeochemical Si cycle in marine environments.

In this paper, a model of liquid desiccant evaporative cooling system is presented and simulated. The objective of this paper is to reveal the effects of various parameters on thermodynamic performance and to show the optimal range of those parameters. These results show that the system performance is strongly influenced by the hot water temperature, the flow ratio of air to solution and ambient air relative humidity, followed by the hot water flow rate. And the optimal range of each influencing factor is determined as follows: hot water temperature and the value of m a / m s are adopted to be about 75 °C and 1 kg⋅kg−1 respectively, while hot water flow rate will not be greater than 0.6 kg⋅s−1 and the range of the relative humidity of the atmosphere is wide. The analysis of the exergy efficiency ratio shows that the regenerator (REG), dehumidifier (DEH) and the enthalpy exchanger (EX) in the system are the weak parts of the system.

The stability and persistence of organic matter (OM) in source rocks are of great significance for hydrocarbon generation and the global carbon cycle. Clay-OM associations commonly occur in sedimentation and diagenesis processes and can influence the pyrolytic behaviors of OM. In this study, clay-OM complexes, i.e., interlayer clay-OM complexes and clay-OM mixture, were prepared and exposed to high-pressure pyrolysis conditions in confined gold capsule reactors to assess variations in OM pyrolysis products in the presence of clay minerals. Three model organic compounds, octadecanoic acid (OA), octadecy trimethyl ammonium bromide (OTAB), and octadecylamine (ODA), were employed and montmorillonite (Mt) was selected as the representative clay mineral. The solid acidity of Mt plays a key role in affecting the amount and composition of the pyrolysis gases generated by the clay-OM complexes. The Bronsted acid sites significantly promote the cracking of hydrocarbons through a carbocation mechanism and the isomerization of normal hydrocarbons. The Lewis acid sites are primarily involved in the decarboxylation reaction during pyrolysis and are responsible for CO 2 generation. Mt exhibits either a catalysis effect or pyrolysis-inhibiting during pyrolysis of a given OM depending on the nature of the model organic compound and the nature of the clay-OM complexation. The amounts of C 1–5 hydrocarbons and CO 2 that are released from the Mt-OA and Mt-ODA complexes were higher than those of the parent OA and ODA, respectively, indicating a catalysis effect of Mt. In contrast, the amount of C 1–5 hydrocarbons produced from the pyrolysis of Mt-OTAB complexes was lower than that of OTAB, which we attribute to an inhibiting effect of Mt. This pyrolysis-inhibiting effect works through the Hoffmann elimination that is promoted by the catalysis of the Bronsted acid sites of Mt, therefore releasing smaller amounts of gas hydrocarbons than the nucleophilic reaction that is induced by the halide ions in OTAB. In particular, the interlayer space of Mt acts as an ‘amplifier’ that magnifies the above-mentioned catalysis or pyrolysis-inhibiting effect, due to the greater number of Bronsted acid sites with high acidity in the interlayer space. These findings are potentially important for understanding the storage and transfer mechanisms of natural OM in sedimentation and diagenesis processes.

Montmorillonite (Mt), kaolinite (Kaol) and halloysite (Hal) are commonly investigated porous clay minerals, but their performance for the adsorption of volatile organic compounds (VOC) was rarely studied. In this work, the dynamic adsorption of benzene, as a model VOC, on Mt, Kaol and Hal was investigated. The effect of the microstructures of the above-mentioned clay minerals on benzene adsorption were explored by comparing the benzene adsorption of the different derivates of these clay minerals, which were obtained by adjusting the interlayer space and the porosity of the clay minerals through heating treatment. Calcium-based montmorillonite (Ca2 +-Mt) heated at 120 °C exhibited higher benzene adsorption capacity (141.2 mg/g) than sodium-based montmorillonite (Na+-Mt) heated at 120 °C (87.1 mg/g), because the interlayer distance of Ca2 +-Mt was sufficiently large to accommodate the adsorption of benzene. However, for calcined Ca2 +-Mt and Na+-Mt, the collapse of their interlayer space resulted in that the interlayer micropores no longer existed and reduced benzene adsorption. Kaol exhibited the lowest benzene adsorption capacity (56.7 mg/g) among the studied clay minerals because its interlayer space was not available for adsorption and because its specific surface area (SSA) was relatively small. As a polymorph of Kaol but with a tubular morphology, Hal showed a higher benzene adsorption capacity than Kaol owing to its larger SSA. In particular, heating at 120 °C resulted in the increase of the benzene adsorption of Hal, which was ascribed to the exposure of the adsorption sites initially occupied by water molecules. These results demonstrate that the benzene adsorption capacity of the above-mentioned clay minerals was not only highly related to their SSA but also strongly affected by their porosity features.

A spatial separated source delivery (SSSD) method has been proposed to alleviate parasitic reactions between group III precursors and ammonia (NH3) in gas phase using the MOCVD. AlGaN alloys and GaN films grown on sapphire has been prepared with this method. The influence of parasitic reactions on the qualities and properties of AlGaN and GaN films is investigated in detail. High-resolution X-ray diffraction (HRXRD) measurements show that the aluminum composition in materials rises up close to the ratio of trimethylaluminum (TMAl) supply when the supply ratio of TMAl is 0.2, 0.3 and 0.4 respectively, which demonstrates that the parasitic reactions are suppressed mostly. In-situ monitor reflectometer spectra for GaN show that the growth rate gets a 20% increase in comparison with materials grown without the SSSD method. Subsequently, the relationship between parasitic reactions and other reaction types are elucidated. The effect of the SSSD method on parasitic reactions is also systematically studied. Reactions are controlled to change from combination reactions to pyrolysis reactions and surface reactions with the SSSD method. A 2-inch GaN/AlGaN heterostructure is also prepared to evaluate the uniform electrical properties grown with this method. The result indicates that the SSSD method provides a better way to prepare high-quality III-nitride materials, especially for AlN and related alloys.

Residual stress distribution in soldered structure of Kovar alloy and Al2O3 ceramics was determined using XRD analyses. In order to measure the residual stress, position of the characteristic diffraction peak and stress constant were obtained using several versatile/advanced techniques after calibration. Residual stress of soldered structure was measured based on the diffraction patterns obtained for the distribution of residual stress in the soldered joint. Only diffraction peak at 149° for Kovar alloy and two diffraction peaks ranging from 140-170° for Al2O3 ceramics were found to be appropriate for the residual stress determination. It was also confirmed that for Al2O3 ceramics the XRD peak at 152° reflects the changes of stress more precisely than the one at 146°. The stress constant K of Kovar alloy and Al2O3 ceramics was found to be −197MPa/° and −654MPa/°, respectively. After soldering, the maximum residual stress of the soldered joint of both materials developed at 1mm from the soldering seam, and the values within 3mm from the soldering seam are generally significant. Thus, it is important to pay attention to the area of 3mm from the soldering seam in practical application.

Diatoms play an important role in marine biogeochemical cycle of aluminum (Al), as dissolved Al is taken up by diatoms to build their siliceous frustules and is involved in the sedimentation of diatomaceous biogenic silica (BSi). The Al incorporation in BSi facilitates decreasing the dissolution of marine BSi and thus substantially influences the biochemical processes driven by diatoms, such as CO2 sequestration. However, the role of lake BSi in the terrestrial biochemical Al cycle has not been explored, though lakes represent the second-largest sink for BSi. By identifying the previously unexplored high Al/Si atomic ratios (up to 0.052) in lake BSi, here we show lake BSi is a large terrestrial Al pool due to its high Al content, and lake sedimentary BSi constitutes a significant global sink for Al, which is on the same magnitude as the Al sink in global oceans., Diatoms drive biogeochemical cycling of aluminum by incorporating this element into their shells, but this process has not been quantified in freshwater systems. Here the authors quantify diatom-mediated aluminum fluxes in lakes and determine that they rival the aluminum sink in the global ocean.

The progressive decline and eventual loss of islet β-cell function underlies the pathophysiological mechanism of the development of both type 1 and type 2 diabetes mellitus. The recovery of functional β-cells is an important strategy for the prevention and treatment of diabetes. Based on similarities in developmental biology and anatomy, in vivo induction of differentiation of other types of pancreatic cells into β-cells is a promising avenue for future diabetes treatment. Pancreatic stellate cells (PSCs), which have attracted intense research interest due to their effects on tissue fibrosis over the last decade, express multiple stem cell markers and can differentiate into various cell types. In particular, PSCs can successfully differentiate into insulin- secreting cells in vitro and can contribute to tissue regeneration. In this article, we will brings together the main concepts of the translational physiology potential of PSCs that have emerged from work in the field and discuss possible ways to develop the future renewable source for clinical treatment of pancreatic diseases.