Effects on the Physicochemical Properties of Hydrochar Originating from Deep Eutectic Solvent (Urea and ZnCl2)-Assisted Hydrothermal Carbonization of Sewage Sludge

Deep eutectic solvents (DESs) (ZnCl2 and urea) have been used to solubilize organic matter from sewage sludge (SS), followed by subsequent hydrothermal carbonization (HTC) to obtain low-nitrogen-content hydrochar. The nitrogen content in hydrochar obtained after DES addition decreased to 1.93 from 3.15% (no DES) at 210 °C. DES can notably dissolve proteins and lipids during HTC of SS. HTC of polysaccharides was enhanced, increasing the degree of carbonization. The key role of DES in SS during HTC was the dissolution of proteins, promoting carbonization of polysaccharides, Maillard reactions, deamination, and decarboxylation of proteins. ZnCl2 was probably converted into β-Zn(OH)C1 and ZnO during HTC. Results pointed to relevant enhancements when DES was added, useful for organic waste valorization such as SS, food waste, poultry manure, and related waste feedstock

NO signaling and S-nitrosylation regulate PTEN inhibition in neurodegeneration

<p>Abstract</p> <p>Background</p> <p>The phosphatase PTEN governs the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway which is arguably the most important pro-survival pathway in neurons. Recently, PTEN has also been implicated in multiple important CNS functions such as neuronal differentiation, plasticity, injury and drug addiction. It has been reported that loss of PTEN protein, accompanied by Akt activation, occurs under excitotoxic conditions (stroke) as well as in Alzheimer's (AD) brains. However the molecular signals and mechanism underlying PTEN loss are unknown.</p> <p>Results</p> <p>In this study, we investigated redox regulation of PTEN, namely S-nitrosylation, a covalent modification of cysteine residues by nitric oxide (NO), and H₂O₂-mediated oxidation. We found that S-nitrosylation of PTEN was markedly elevated in brains in the early stages of AD (MCI). Surprisingly, there was no increase in the H₂O₂-mediated oxidation of PTEN, a modification common in cancer cell types, in the MCI/AD brains as compared to normal aged control. Using several cultured neuronal models, we further demonstrate that S-nitrosylation, in conjunction with NO-mediated enhanced ubiquitination, regulates both the lipid phosphatase activity and protein stability of PTEN. S-nitrosylation and oxidation occur on overlapping and distinct Cys residues of PTEN. The NO signal induces PTEN protein degradation via the ubiquitin-proteasome system (UPS) through NEDD4-1-mediated ubiquitination.</p> <p>Conclusion</p> <p>This study demonstrates for the first time that NO-mediated redox regulation is the mechanism of PTEN protein degradation, which is distinguished from the H₂O₂-mediated PTEN oxidation, known to only inactivate the enzyme. This novel regulatory mechanism likely accounts for the PTEN loss observed in neurodegeneration such as in AD, in which NO plays a critical pathophysiological role.</p

Metabolomic analysis of the brain and blood from rats exposed to high-dose chlorpyrifos

Chlorpyrifos is an organophosphate pesticide used to kill pests such as insects and worms. Wide use of chlorpyrifos has led to serious safety concerns worldwide. Research on the mechanism of action of chlorpyrifos poisoning is continuing. We investigated changes in the small-molecular metabolites in the brain and blood of rats upon exposure to chlorpyrifos at an acute-poisoning dose. Rats were given twice the lowest dose of chlorpyrifos that is lethal for 100% of exposed animals (2 × LD100) and then killed after 2 h. After treatment, gas chromatography-mass spectrometry was used to analyze the metabolomic changes in the brain and blood samples of rats. An increase in blood levels of creatinine and uric acid were noted, along with a decrease in levels of various amino acids. These changes suggested that chlorpyrifos exposure may damage kidney function and cause disorders in amino-acid metabolism of rats. Decreased concentrations of gamma-aminobutyric acid and niacinamide in the brain and increased concentrations of 3-hydroxybutyric acid in rats with acute poisoning by chlorpyrifos were observed, which may suggest oxidative damage in the body

Cloning and characterization of enoate reductase with high β-ionone to dihydro-β-ionone bioconversion productivity

Abstract Background Dihydro-β-ionone is a principal aroma compound and has received considerable attention by flavor and fragrance industry. The traditional method of preparing dihydro-β-ionone has many drawbacks, which has restricted its industrial application. Therefore, it is necessary to find a biotechnological method to produce dihydro-β-ionone. Results In this study, the enoate reductase with high conversion efficiency of β-ionone to dihydro-β-ionone, DBR1, was obtained by screening four genetically engineered bacteria. The product, dihydro-β-ionone, was analyzed by GC and GC-MS. The highest dihydro-β-ionone production with 308.3 mg/L was detected in the recombinant strain expressing DBR1 which was later on expressed and purified. Its optimal temperature and pH were 45 °C and 6.5, respectively. The greatest activity of the purified enzyme was 356.39 U/mg using β-ionone as substrate. In the enzymatic conversion system, 1 mM of β-ionone was transformed into 91.08 mg/L of dihydro-β-ionone with 93.80% of molar conversion. Conclusion DBR1 had high selectivity to hydrogenated the 10,11-unsaturated double bond of β-ionone as well as high catalytic efficiency for the conversion of β-ionone to dihydro-β-ionone. It is the first report on the bioconversion of β-ionone to dihydro-β-ionone by using enoate reductase

Rational design of strontium antimony co-doped Li7La3Zr2O12 electrolyte membrane for solid-state lithium batteries

Considering significant safety advantages, all solid-state LIBs have attracted considerable attentions as alternative power sources for electric vehicles where safety is a big concern, while the development of solid electrolyte membrane with high lithium-ion conductivity, negligible electron conductivity and high stability is the key challenge. Here, Sr and Sb co-doping strategy was applied to further improve the sintering capability and conductivity properties of Li7La3Zr2O12 garnet-type electrolytes. Specifically, Li6.6+xLa3-xSrxZr1.6Sb0.4O12 (x = 0–0.2) oxides were designed and the physical and electrochemical performance of the various materials were comparatively studied. The results of X-ray diffraction and Raman spectra revealed Li6.6+xLa3-xSrxZr1.6Sb0.4O12 (x = 0–0.2) prepared by conventional solid-state reaction was in cubic structure. The introduction of a small amount of Sr into the La sites is beneficial for membrane densification and lithium-ion mobility, turning out high density of 95.1% and ionic conductivity of 8.83 × 10−4 S cm−1 at room temperature. The EIS showed the doping of Sr in La sites resulted in improved conductivity at both grain boundary and the oxide bulk. The batteries consisting of lithium film anode, Li6.66La2.94Sr0.06Zr1.6Sb0.4O12 solid electrolyte membrane and LiFePO4 cathode reached the first discharge capacity of 157 mAh g−1 at 0.1 C between 4.2 and 2.0 V (vs. L/Li+) with capacity retention of 93% after 100 cycles at ambient temperature. These results displayed that the Sr, Sb co-doped LLZO electrolytes are alternative for all solid-state Li-ion batteries

EFFECTS OF EXTRACTION METHODS ON THE FUEL CHARACTERISTICS AND DIESEL ENGINE PERFORMANCES OF JATROPHA CURCAS BIODIESEL

The development of high-quality biodiesel fuel has become more relevant due to the limited reserve and environmental effects of fossil fuel. In this study, oils derived from Jatropha curcas seeds through two extraction methods (soxhlet and cold-press) were compared. The fuel characteristics investigation suggested that methyl ester derived from oil extracted with the soxhlet method has lower viscosity, higher calculated cetane index, and slightly higher sulphur content. Comparison on the fuel characteristics with biodiesel standards showed that the methyl esters still had substantial amount of methanol and water due to low temperature during transesterification. The oils were also compared for their engine performances in a diesel engine under engine rotation of 1800 to 3000 RPM by blending derived methyl ester with pure petro-diesel to create B20 biodiesel. On average, B20 from soxhlet extraction has 3.86% higher power output, 3.55% higher torque, 3.4% higher BMEP, and 5.89% lower BSFC compared to cold-press. The extraction method affects the fuel characteristics of the methyl ester and the engine performances of the B20 biodiesel

STUDY OF MICROSTRUCTURE AND DEFECTS IN HYDROGENATED MICROCRYSTALLINE SILICON FILMS

Microcrystalline silicon films were deposited by very high frequency (VHF) plasma-enhanced chemical vapor deposition (PECVD) with different hydrogen dilution. The microstructure of these films was investigated using Raman spectroscopy and infrared absorption (IR) spectra. The crystalline, amorphous, and grain boundary volume fractions X-c, X-a and X-gb were estimated from Raman measurements. An interface structure factor (R-if) is proposed to characterize the grain boundary volume fractions in IR spectroscopy. The density of states (DOS) of the microcrystalline crystalline silicon films were studied by phase-shift analysis of modulated photocurrent (MPC) and photoconductivity spectroscopy. It was observed that DOS increases with increasing grain boundary volume fractions, while the values of electron mobility-lifetime product mu T-e(e) disease

Cross-Linked Small-Molecule Micelle-Based Drug Delivery System: Concept, Synthesis, and Biological Evaluation

Lessons from the covalent capture of small-molecule self-assemblies (monomer molecular weight of <500.0) are applied to grow a generic cross-linked small-molecule micelle-based drug delivery system (CSM-DDS), which has significant advantages over the popular polymeric micelle-based drug delivery systems in terms of drug loading, stability, monomer purity, and cost of preparation. A proof-of-concept CSM-DDS constructed by one-step synthesized amphiphile <b>1</b> with anticancer drug gemcitabine confirms the feasibility of the new strategy via its high drug loading content (up to 58%), robust stability, superior predictable biosafety, facile functionalization, and remarkable anticancer activity both <i>in vitro</i> and <i>in vivo</i>