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Numerical simulations of the deformation, aggregation, and migration processes of emulsified oil droplets under the influence of a multiphase field were conducted using COMSOL software. Combined with laboratory experiments, an existing process was improved and optimized by introducing the concept of "precise aeration." The results indicate that aeration can enhance the efficiency of electrochemical demulsification, with the gas field accelerating the deformation, aggregation, and migration processes of the oil droplets. Leveraging the numerical simulation results, laboratory experiments were conducted to optimize the aeration intensity and duration, which were reduced to 1.5 L/min and 60 min. At this point, the oil content and chemical oxygen demand (COD) of the emulsified oil wastewater were only 4.98 mg/L and 101 mg/L, respectively. The demulsification mechanism was analyzed, revealing that under the combined action of the electric field and gas field, oil droplets underwent a polarization reaction and were aggregated into larger droplets. Aeration expedited the weakening of the mechanical strength at the oil-water interface of the droplets, which significantly improved the demulsification, coalescence, and flotation removal of the emulsified oil droplets. This study holds significant importance for the process improvement and mechanistic analysis of electrochemical demulsification for oil removal.

The harsh conditions of the gastrointestinal tract limit the potential health benefits of oral probiotics. It is promising that oral bioavailability is improved by strengthening the self-protection of probiotics. Here, we report the encapsulation of a probiotic strain by endogenous production of hyaluronan to enhance the effects of oral administration of the strain. The traditional probiotic Streptococcus thermophiluswas engineered to produce hyaluronan shells by using traceless genetic modifications and clustered regularly interspaced short palindromic repeat interference. After oral delivery to mice in the form of fermented milk, hyaluronan-coated S. thermophilus(204.45 mg/L hyaluronan in the milk) exhibited greater survival and longer colonization time in the gut than the wild-type strain. In particular, the engineered probiotic strain could also produce hyaluronan after intestinal colonization. Importantly, S. thermophilusself-encapsulated with hyaluronan increased the number of goblet cells, mucus production, and abundance of the microorganisms related to the biosynthesis of short-chain fatty acids, resulting in the enhancement of the intestinal barrier. The coating formed by endogenous hyaluronan provides an ideal reference for the effective oral administration of probiotics.

Thermoelectric materials convert heat energy into electricity, hold promising capabilities for energy waste harvesting, and may be the future of sustainable energy utilization. In this work, we successfully synthesized core–shell Bi2Te3/Sb2Te3(BTST) nanostructured heterojunctions via a two-step solution route. Samples with different Bi2Te3core to Sb2Te3shell ratios could be synthesized by controlling the reaction precursors. Scanning electron microscopy images show well-defined hexagonal nanoplates and the distinct interfaces between Bi2Te3and Sb2Te3. The similarity of the area ratios with the precursor ratios indicates that the growth of the Sb2Te3shell mostly took place on the lateral direction rather than the vertical. Transmission electron microscopy revealed the crystalline nature of the as-synthesized Bi2Te3core and Sb2Te3shell. Energy-dispersive X-ray spectroscopy verified the lateral growth of a Sb2Te3shell on the Bi2Te3core. Thermoelectric properties were measured on pellets obtained from powders via spark plasma sintering with two different directions, in-plane and out-of-plane, showing anisotropic properties due to the nanostructure alignment in the pellets. All samples showed a degenerate semiconducting character with the electrical resistivity increasing with the temperature. Starting from Sb2Te3, the electrical resistivity increases with the increase in amounts of Bi2Te3. Thermal conductivity is lowered due to the increase in interfaces and additional phonon scattering. We show that the out-of-plane direction of the BTST 1-3 sample (where 1-3 indicates the ratio of BT to ST) demonstrates a high Seebeck value of 145 μV/K at 500 K which may be attributed to an energy filtering effect across the heterojunction interfaces. The highest overall zTis observed for the BTST 1-3 sample in the out-of-plane direction at 500 K. The zTvalues increase continuously over the measured temperature range, indicating a probable higher value at increased temperatures.

Synthetic towards homogeneous heparin oligosaccharides are increasing in terms of the number of products and the synthetic scale. The dual-function glycosyltransferase Pasteurella multocidaheparosan synthase 2 (PmHS2) is widely used in these synthetic approaches. However, the unwanted degradation (caused by multi-step reverse-glycosylation) action of PmHS2 limits the catalytic efficiency of the process and the purity of the products, especially when the target oligosaccharide is longer than a hexasaccharide. Here, we found that the degradation is due to the coexistence of two catalytic domains in PmHS2, which suggested that an approach employing single-function glycosyltransferases could overcome this problem. By screening members of the KfiA family, we obtained a novel single-function heparosan: α1-4-N-acetylglucosaminyltransferase from Neisseria animaloris, which had an excellent recombinant expression level in Escherichia coli. Then, multiple rounds of structure-guided site-directed mutagenesis of the enzyme, named NaKfiA, were performed, producing an NaKfiA C16L/S165K double-mutant with drastically improved enzyme activity and stability compared with wild-type NaKfiA, but retaining the excellent production level and substrate promiscuity. NaKfiA(C16L/S165K) purified from the cell lysate of 1 liter of fermented E. coliproduced 14.65 mmol α1,4-linkage. Combining NaKfiA(C16L/S165K) with the single-function glucuronyltransferase EcKfiC from E. coliK5, size-defined heparosan oligosaccharides were accessible with 96–98% yield in sequential enzymatic reactions, while unwanted oligosaccharide byproducts were minimized. Overall, our study resulted in an efficient engineered biocatalyst and established a biocatalytic approach for size-controlled synthesis of heparosan oligosaccharides relying on two single-function glycosyltransferases.

Doped and alloyed germanium nanocrystals (Ge NCs) are potential candidates for a variety of applications such as photovoltaics and near IR detectors. Recently, bismuth (Bi) as an n-type group 15 element was shown to be successfully and kinetically doped into Ge NCs through a microwave-assisted solution-based synthesis, although Bi is thermodynamically insoluble in bulk crystalline Ge. To expand the composition manipulation of Ge NCs, another more common n-type group 15 element for semiconductors, antimony (Sb), is investigated. Oleylamine (OAm)- and OAm/trioctylphosphine (TOP)-capped Sb-doped Ge NCs have been synthesized by the microwave-assisted solution reaction of GeI2with SbI3. Passivating the Ge surface with a binary ligand system of OAm/TOP results in formation of consistently larger NCs compared to OAm alone. The TOP coordination on the Ge surface is confirmed by 31P NMR and SEM-EDS. The lattice parameter of Ge NCs increases with increasing Sb concentration (0.00–2.0 mol %), consistent with incorporation of Sb. An increase in the NC diameter with higher content of SbI3in the reaction is shown by TEM. XPS and EDS confirm the presence of Sb before and after removal of surface ligands with hydrazine and recapping the Ge NC surface with dodecanethiol (DDT). EXAFS analysis suggests that Sb resides within the NCs on highly distorted sites next to a Ge vacancy as well as on the crystallite surface. High Urbach energies obtained from photothermal deflection spectroscopy (PDS) of the films prepared from pristine Ge NC and Sb-doped Ge NCs indicate high levels of disorder, in agreement with EXAFS data. Electrical measurements on TiO2–NC electron- and hole-only devices show an increase in hole conduction, suggesting that the Sb-vacancy defects are behaving as a p-type dopant in the Ge NCs, consistent with the vacancy model derived from the EXAFS results.

Indirect ligand exchange methods have been demonstrated to replace the oleylamine capping with dodecanethiol for germanium nanocrystals (Ge NCs). In these methods, hydrazine is employed to effectively remove the oleylamine ligand before the NCs are passivated by microwave-assisted heating with dodecanethiol. In this work, octadecanethiol passivation is accomplished by the in situreaction of dioctadecyl disulfide with diphenylphosphine. 1H NMR and FTIR are used to characterize the surface ligand capping and the effectiveness of ligand exchange. Thiol passivation is achieved either by an exchange reaction at room temperature or by using microwave-assisted heating. Indirect and direct ligand exchange methods are demonstrated to be effective. The microwave-assisted reaction of GeI2with dioctadecyl disulfide also achieves thiol passivation without interfering in the formation of Ge NCs. Additional experiments study the effects of nanoparticle synthesis temperature, solvent, and ligand concentration on the exchange of oleylamine for octadecanethiol ligands.

We present the application of N-difluoroacetylglucosamine (GlcNDFA) in a chemical evolution strategy to synthesize oligosaccharides. In comparison to conventional N-trifluoroacetylglucosamine, GlcNDFA exhibits superior substrate compatibility with glycosyltransferases as well as stability in aqueous environments. Using our 16-step assembly line, GlcNDFA can be used to produce homogeneous dekaparin, a heparin-like medication, with a yield of 62.2%. This underscores the significant potential of GlcNDFA as a chemical evolution precursor in the precise synthesis of structurally defined polysaccharides.

Several studies have suggested that excellent therapeutic outcomes can be achieved with conservative treatment of proximal humeral epiphyseal fractures in patients younger than 11 years old; however, the outcomes of conservative treatment for children older than 11 years are controversial. To address this problem, this study compared outcomes of conservative treatment for proximal humeral epiphyseal fractures in pediatric patients of different ages. The patients were divided into two groups for comparative purposes based on age. Group I consisted of 34 patients who were less than 11 years old (average age: 5 years) and group II included 21 patients who were 11 years of age or older (average age: 14 years). Patients in both groups underwent conservative treatment and follow-up examination, where they first were examined with X‑radiography for assessment of deformity, fracture union and loss of reduction. At the final follow-up after 2 years, patients were assessed by an interview and a detailed physical examination including the assessment of shoulder function using the Constant-Murley score. There were no significant differences in the grading scale of varus deformity between the two groups (P> 0.05) after immediate postreduction X‑radiography; however, there were significant differences in the grading scale of varus deformity between group I and group II at the 2‑year follow-up (P< 0.05). There were no significant differences between the two groups with respect to the Constant-Murley score and arm length discrepancy (P> 0.05) at final follow-up examinations. In general, the results suggested that the outcomes, as measured with radiographs, for both older and young children were comparable after immediate postreduction roentgenograms. For long-term follow-up there was a difference between the two groups and the degree of angulation and displacement might be associated with treatment outcomes for older children. Thus, these factors should be considered when treating and evaluating the outcomes for older children. Mehrere Studien haben gezeigt, dass durch die konservative Behandlung proximaler humeraler epiphysärer Frakturen bei Patienten <11 Jahren exzellente therapeutische Ergebnisse erzielt werden können. Jedoch sind die Ergebnisse der konservativen Behandlung bei Kindern >11 Jahren kontrovers. Um dieses Problem zu adressieren, verglich man in dieser Studie die Ergebnisse der konservativen Behandlung proximaler humeraler epiphysärer Frakturen bei Kindern unterschiedlichen Alters. Gruppe I bestand aus 34 Patienten, die jünger als 11 Jahre waren (Durchschnittsalter 5 Jahre), und Gruppe II schloss 21 Patienten ein, die 11 Jahre oder älter waren (Durchschnittsalter: 14 Jahre). Die Patienten beider Gruppen erhielten eine konservative Behandlung sowie eine Follow-up-Untersuchung, bei der sie mittels Röntgenaufnahmen untersucht wurden, um Deformität, Frakturheilung und den Reduktionsverlust zu beurteilen. Beim letzten Follow-up nach 2 Jahren wurden die Patienten mittels eines Interviews und einer detaillierten körperlichen Untersuchung bewertet, einschließlich der Beurteilung der Schulterfunktion mittels Constant-Murley-Score. Es gab keine signifikanten Unterschiede in der Klassifikationsskala für Varusdeformität zwischen den 2 Gruppen (p> 0,05) nach der sofortigen Röntgenaufnahme nach Reduktion. Jedoch gab es signifikante Unterschiede in der Klassifikationsskala für Varusdeformität zwischen Gruppe I und Gruppe II beim 2‑Jahres-Follow-up (p< 0,05). Hinsichtlich des Constant-Murley-Scores und der Armlängendiskrepanz (p> 0,05) wurden zwischen den beiden Gruppen bei der letzten Follow-up-Untersuchung keine signifikanten Unterschiede festgestellt. Im Allgemeinen zeigten die Ergebnisse, dass die mittels Röntgenaufnahmen erfassten Outcomes sowohl bei älteren als auch bei jüngeren Kindern nach einer sofortigen Röntgenaufnahme nach Reduktion vergleichbar waren. Im Langzeit-Follow-up wurde ein Unterschied zwischen den beiden Gruppen festgestellt, und dass Angulationsgrad und Dislokation mit den Behandlungsergebnissen älterer Kinder assoziiert sein könnten. Daher sollten diese Faktoren bei der Behandlung und Evaluation der Ergebnisse älterer Kinder berücksichtigt werden.

Glycosaminoglycan synthases have immense potential in applications involving synthesis of oligosaccharides, using enzymatic approaches and construction of cell factories that produce polysaccharides as critical metabolic components. However, the use of high-throughput activity assays to screen for the evolution of these enzymes can be challenging because there are no significant changes in fluorescence or absorbance associated with glycosidic bond formation. Here, using incorporation of azido-labeled N-acetylhexosamine analogs into bacterial capsule polysaccharides via bacterial metabolism and bioorthogonal chemistry, fluorophores were specifically introduced onto cell surfaces. Furthermore, correlations between detectable fluorescence signals and the polysaccharide-synthesizing capacity of individual bacteria were established. Among 10 candidate genes, 6 members of the chondroitin synthase family were quickly identified in a recombinant Bacillus subtilishost strain. Additionally, directed evolution of heparosan synthase was successfully performed using fluorescence-activated cell sorting of recombinant Escherichia coliO10:K5(L):H4, yielding several mutants with increased activity. Cell-based approaches that selectively detect the presence or absence of synthases within an individual colony of bacterial cells, as well as their level of activity, have broad potential in the exploration and engineering of glycosaminoglycan synthases. These approaches also support the creation of novel strategies for high-throughput screening of enzyme activity based on cell systems.

MicroRNAs (miRNAs) are a specialized class of small silencing RNAs that regulate gene expression in eukaryotes. In plants, miRNAs negatively regulate target mRNAs containing a highly complementary sequence by either mRNA cleavage or translational repression. As a model plant to study fleshy fruit ripening, miRNA studies in tomato have made great progress recently. MiRNAs were predicted to be involved in nearly all biological processes in tomato, particularly development, differentiation, and biotic and abiotic stress responses. Surprisingly, several miRNAs were verified to be involved in tomato fruit ripening and senescence. Recent studies suggest that miRNAs are related to host-virus interactions, which raises the possibility that miRNAs can be used as diagnostic markers for response to virus infection in tomato plants. In this review, we summarize our current knowledge systematically and advance future directions for miRNA research in tomato.

This paper proposed a hierarchical structure model of the electronic system firstly, and then the expression method of the structure matrix was optimized. After that, the repair question of the system with redundant module was analyzed and turned into a kind of matrix solving, and the redundant repairs algorithm was provided at the same time. By repairing one bit half adder with one redundant mould, the feasibility of this method was proved and a new thought for the electronic system repair online was raised.

Active vibration control based on fuzzy algorithm for piezoelectric smart plate is studied. After the characteristic of piezoelectric ceramic (PZT) is analyzed, modal and transient analysis are developed in this paper with finite element model of the piezoelectric smart plate constructed in ANSYS. Fuzzy logic control rules are established by the analysis of the deformation of the plate. With mode shape and displacement response curve obtained, active vibration suppression for the smart plate system is achieved by using commercial finite element programs. The simulation results illustrate that analysis of piezoelectric smart plate using ANSYS is practicable and the intelligent control method is effective.

An endophytic bacterial strain, Jaas ed1, was isolated from the interior of eggplant (Solanum melongenaL.) stems in Jiangsu Province, China. According to the morphological and physiological characteristics and phylogenetic analysis of the 16s rDNA sequence, it was identified as Bacillius subtilis. Strain Jaas ed1 and its cell-free filtrate had strong antifungal activity against Verticillium dahliae. The strain was an internal colonizer within the eggplant without any harmful side effects to the plant. In greenhouse experiments, the strain cell suspension effectively controlled Verticillium wilt of eggplant, and its control efficiency was far more significant than that of the cell-free filtrate after inoculation of V. dahliae.

Organ transplant rejection (OTR) is a complex immune reaction involving multiple cells, and it determines graft survival and patient prognosis. At present, most transplant recipients are administered a combination of immunosuppressive and biological agents to protect them from OTR. However, immunosuppressive agents negatively impact the immune system of the patients, causing them to suffer from serious complications, such as chronic infection and malignant tumors. Therefore, a thorough understanding of the mechanisms involved in immune tolerance and immune rejection with regard to organ transplant (OT) is essential for developing better treatment options and improving patient outcomes. This article reviews the role of immune cells in OTR and organ transplant tolerance (OTT), including the novel cell therapies that are currently under clinical trials for transplant recipients.

The nanoparticles of a centrosymmetric material titanium dioxide (TiO2) have been synthesied and characterized by hyper-Rayleigh scattering (HRS) technique. The particles with mean diameter of 10 nm have large first order hyperpolarizability in solution, which arise from the surface layer of the particles.

Optimized conditions are developed for the synthesis of the title compounds, which are of high interest in medicinal chemistry.

The title phosphor is synthesized by the sol—gel method starting with an aqueous solutions containing Ca(NO3)2, SnCl4, Sm2O3, HNO3, and citric acid (90 °C, calcination of the obtained gel at 900 °C for 6 h in air).

The new orange phosphors Sr1‐xSmxWO4(x = 0.02—0.06) are synthesized by solid state reaction of SrCO3, WO3, and Sm2O3(alumina crucible, 1050—1100 °C, 3 h).

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