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Cryptococcus spp. is an invasive fungal pathogen and causes life-threatening cryptococcosis. Opportunistic cryptococcal infections among the immunocompromised population are mostly caused by Cryptococcus neoformans, whereas the geographical dissemination of Cryptococcus gattii in recent years has threatened lives of even immunocompetent people. The capsule, mainly composed of glucuronoxylomannan (GXM) polysaccharides, plays important roles in the virulence of Cryptococcus spp. The assembling mechanism of GXM polysaccharides into the capsule is little understood because of insufficient experimental data. Molecular modeling and molecular dynamics simulation provide insight into the assembling process. We first built GXM oligosaccharide models of serotypes D, A, B, and C and extracted their secondary structure information from simulation trajectories. All the four mainchains tend to take the nearly twofold helical conformation, whereas peripheral sidechains prefer to form left-handed helices, which are further stabilized by intramolecular hydrogen bonds. Based on the obtained secondary structure information, GXM polysaccharide arrays were built to simulate capsule-assembling processes of C. neoformans and C. gattii using serotypes A and C as representatives, respectively. Trajectory analysis illustrates that electrostatic neutralization of acidic sidechain residues of GXM is a prerequisite for capsule assembling, followed by formation of intermolecular hydrogen bond networks. Further insight into the assembling mechanism of GXM polysaccharides provides the possibility to develop novel treatment and prevention solutions for cryptococcosis.Neurosurgical procedures often cause damage to the brain tissue at the periphery from surgical manipulations. Especially during retraction, a large amount of pressure could be applied on the brain surface, which can damage it, leading to brain herniation, which can be fatal for patients. To resolve this issue, we have developed a pressure sensor that can be used to monitor the applied pressure during surgery for intraoperative care. This device was tested on a rodent model to create a superficial surgically induced damage profile for three different applied pressures (30, 50, and 70 mmHg) and compared to a standard intracranial pressure monitoring system. Magnetic resonance imaging has been performed after surgical procedures to detect the herniation caused by applied pressure. To evaluate the damage to brain cells and tissue rupture, histological analysis was performed using hematoxylin and eosin staining. A scoring system was developed to understand the severity of the surgically induced brain injury, which will help neurosurgeons to limit the pressure to an optimum point without causing damage.Oily sludge is a hazardous waste. If not handled properly, it can not only pollute the environment but also endanger human health. This study is the first to use a response surface method to optimize the main parameters of rhamnolipid-based recovery of oil from oily sludge. Using rhamnolipids as the cleaning agent and the oil recovery fraction as the evaluation index, the factors affecting the cleaning efficiency of oily sludge were optimized. The aforementioned sludge was obtained from the Tarim Oilfield. A single-factor experiment was conducted to determine the optimal range of the dosage, liquid-solid ratio, pH value, and time. [https://www.selleckchem.com/products/cerivastatin-sodium.html Cerivastatin sodium solubility dmso] The Box-Behnken response surface method was used to investigate the influence of each variable on the residual oil fraction of the oily sludge, and the dosage, pH value, and time were found to have a significant impact. The model optimization results show that the best process conditions for rhamnolipid-based recovery of oil are as follows rhamnolipid dosage = 167.785 mg/L; liquid-solid ratio = 4.5891; pH = 9.618; time = 1.627 h. Under optimal conditions, the model-predicted oil recovery fraction and the actual oil recovery fraction were 85.15 and 82.56%, respectively; the relative error between the predicted and the actual values was 2.59%. These results indicate that the model results are reliable. The solid residue after the cleaning was also analyzed to gain an in-depth understanding of the cleaning process. This study determined the feasibility of a rhamnolipid-based solution for the treatment of oily sludge and oil-contaminated soil.The morphological development and thermal properties of different polyamides with long-chain branches without forming a network structure were characterized by differential scanning calorimetry, polarized optical microscopy, and nonisothermal crystallization kinetics. The crystallization characteristics were analyzed using the nonisothermal kinetic equation proposed by Seo. Polarized optical microscopy and the Avrami exponent show the effect of the structural changes on the molecular ordering during the crystallization and early morphological development. The Avrami exponent, n, determined from the analysis of the nonisothermal crystallization kinetics, indicates a reduced heterogeneous nucleation for the modified polyamides. Structural changes (branching) of the polyamides impede crystallization, as indicated by the shift of the crystallization peaks to lower temperatures.Cirsium japonicum Fisch ex DC belongs to the Compositae family and has been used as a folk remedy source in Asian countries because of its health-promoting properties. It is known that C. japonicum contains flavonoids, furans, long-chain alcohols, sterols, and volatile oils. Nevertheless, the molecular mechanism of secondary metabolite biosynthesis remains poorly understood. Therefore, transcriptome analysis and metabolic profiling were performed using different parts of C. japonicum to investigate phenylpropanoid metabolism. Based on the BLASTX search results, we identified 29 orthologs of enzymes responsible for phenylpropanoid biosynthesis. Additionally, 75 metabolites were identified in C. japonicum. Most of the flavonoid biosynthetic genes were significantly expressed ranging from 2.6- to 500-fold higher in the flowers than those in the leaves. Correspondently, the total content of flavonols was 21-fold higher in the flowers than in the roots. However, the total level of flavones showed 58-fold higher amounts in the leaves than in the flowers. Additionally, the total content of flavanols was 19-fold higher in the leaves than in the roots. The results of this study provide transcriptomic and metabolic information to elucidate the tissue-specific phenylpropanoid metabolism of C. japonicum.Acrylamide and dimethyl diallyl ammonium chloride were used as monomers to synthesize a polyelectrolyte molecular deposition film (PMDF) injection agent for solving the problem of high injection pressure of water wells in low-permeability reservoirs. The structure of the PMDF injection agent was determined through IR and 1H nuclear magnetic resonance (NMR). The performance evaluation results show a change of wettability from hydrophilic to neutral wetting with the contact angle changing from 22.32 to 73.31° because of agent injection. It can also change the negative ζ-potential on the surface of the sand to a positive value. For comparison, core displacement experiments involving the commercial Gemini surfactant DF-G reveal that the effects of the depressurization of PMDF are more obvious than those of DF-G. link2 The adsorption stability of the former is better than that of the latter. Especially, under a high-speed water flow of 30 pore volume (PV) injection, the depressurization rate of PMDF is still as high as 43.59%. link3 Finally, the oil-water relative permeability curves and core nuclear magnetic resonance (NMR) experiments demonstrate that the PMDF treatment can reduce the irreducible water saturation, which indicated that the porosity of the flowable part of the core increased and the swept volume was increased. The suitable range of PMDF according to NMR pore-radius distribution within a low-permeability reservoir the flowable partial pore required the throat radius greater than 0.01 μm.The polycrystalline thin films of BiFeO3 (BFO) and Bi0.90Ho0.10Fe1-xTixO (x = 0, 0.025, 0.05, 0.10, 0.15, and 0.20) were successfully synthesized by the simple sol-gel method. X-ray diffraction and Raman spectra revealed the substitution of Bi and Fe by Ho and Ti, respectively, and correspondingly a structural phase transition from the rhombohedral phase to orthorhombic phase. The field-emission scanning electron microscopy and transmission electron microscopy images indicated that the average size of the particles was decreased and the surface homogeneous agglomeration was enhanced with the increased concentration of Ti to x = 0.05. The X-ray photoelectron spectroscopy measurements illustrated that Fe3+ and O2- ions tended to increase with the Ti concentration increase, which accounted for the enhanced super-exchange interaction between Fe3+ and O2-. Because of the reduced concentration of oxygen vacancies, Ho and Ti ions with a smaller ionic radius and denser surface structure, the Ho and Ti co-substituted films with an appropriate concentration of Ti (x = 0.05) showed an optimal saturation magnetization (Ms) of 44.23 emu/cm3 and remanent magnetization (Mr) of 4.62 emu/cm3, which were approximately 1.8 times and 1.9 times than that of the pure BFO, respectively. This work opened up an effective way to modulate the structure and properties of BFO-based materials.In this work, a series of branched polycaprolactone (BPCL) samples with different ε-caprolactone (CL) chain lengths were synthesized and used to toughen poly (lactic acid) (PLA). The spherical structure increased the free volume, facilitating the free movement of the PLA chain segment and increasing the ductility. In addition, the hydrogen bonds between the multi-terminal hydroxyl group of BPCL x and PLA improved the interaction between them. The glass-transition temperatures (Tg) and crystallization temperatures (Tc) of the blends were significantly lower than those of PLA, and these temperatures increased with the chain length of polycaprolactone. BPCL x increased the crystallization rate of PLA through heterogeneous nucleation. A longer chain length of CL increased the mutual entanglement in the blends, reduced the hydrogen bonding between BPCL x and PLA, and increased the entanglement of BPCL x chains. When the chain length of CL was 6, the impact strength and elongation at break of the PLA/BPCL blends exhibited an increase of 151.72 and 465.8%, respectively, as compared with PLA.Because of the high specific surface area, excellent electronic conductivity, facile Li diffusion, and rich functional groups, Ti2C-based MXenes have been widely used to improve the electrochemical property of lithium-sulfur batteries. The complex surface functionalization (such as -OH, -S, -F, and -O) of MXenes boosts the performance but also causes controversies about the favorable functionalized surface in the electrochemical reaction during the charge and discharge process. In the present work, a theoretical study based on density functional theory has been carried out to clarify the favorable functionalized surface by comparing pristine Ti2C and -OH-, -S-, -F-, and -O-functionalized Ti2C surfaces from the aspects of adsorption ability, electronic conductivity, and kinetic conversion ability. It is found that compared with severe polysulfide deformation on pristine Ti2C and Ti2C(OH)2 surfaces, Ti2CO2, Ti2CS2, and Ti2CF2 have effective polysulfide adsorption. Ti2CO2 has the largest surface adsorption energy, followed by Ti2CS2, and Ti2CF2 is the weakest.