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Multiple TonB dependent transporters (TBDTs) contribute to bacterial virulence due to the importance roles that their substrates play in bacterial growth, and possess vaccine potential. A putative TBDT, YncD, had been identified as one of in vivo induced antigens during human infection of typhoid fever, and is required for the pathogenicity of Salmonella enterica Serovar Typhi. The present study was aimed to determine the function and immunogenicity of YncD. Homologous recombination method was used to construct an yncD-deletion mutant and cirA-iroN-fepA-deletion mutant from the wild-type S. Typhi Ty2. The growth of mutants and the wild-type strain were assessed in iron-deficient medium, as well as in human macrophage cells. Recombinant YncD protein was expressed and purified using Ni-NTA affinity chromatography and anion exchange. A mouse model was then used to evaluate the immunogenicity and protection efficacy of the recombinant YncD. Antibody levels, serum bactericidal efficiency, passive immune protection, opsonophagocysis were assayed to analyse the immunoprotection mechanism of the recombinant YncD. Our results showed that YncD is associated with the iron-uptake of S. Typhi. The yncD-deletion mutant displayed impaired growth in iron-deficient medium, comparable to that the cirA-iroN-fepA-deletion mutant did. The mutation of yncD markedly decreased bacterial growth within human macrophage cells. Moreover, subcutaneous immunization of mice with recombinant YncD elicited high levels of specific anti-YncD IgG, IgG1 and IgG2a, which protected the immunized mice against the intraperitoneal challenge of S. Typhi, and decreased bacterial burdens in the livers and spleens of the infected mice. Passive immunization using the immunized sera also efficiently protected the mice from the challenge of S. Typhi. Moreover, the immunized sera enhanced in vitro bactericidal activity of complement, and opsonophagocytosis. Our results showed that YncD displays a role in the iron-uptake of S. Typhi and possesses immunogenicity. [ABSTRACT FROM AUTHOR]

Thermal conductivity is a basic parameter of soil heat transferring, playing an important role in many fields including groundwater withdrawal, ground source heat pump, and heat storage in soils. However, it usually requires a lot of time and efforts to obtain soil thermal conductivity. To conveniently obtain accurate soil thermal conductivity, a new model describes the relationship between soil thermal conductivity (λ) and degree of saturation (Sr) was proposed in this study. Dry soil thermal conductivity (λdry) and saturated soil thermal conductivity (λsat) were described using a linear expression and a geometric mean model, respectively. A quadratic function with one constant was added to calculate λ beyond the lower λdry and upper λsat limit conditions. The proposed model is compared with five other frequently used models and measured data for 51 soil samples ranging from sand to silty clay loam. Results show that the proposed model match the measured data well. The proposed model can be used to determine soil thermal conductivity of a variety of soil textures over a wide range of water content. [ABSTRACT FROM AUTHOR]

We report a facile and controllable approach to design anodic catalysts with different surface morphologies. The RuO-TiO anodes are directly grown in situ on the surface of Ti substrate under certain hydrothermal conditions. X-ray diffraction, field-emission scanning electron microscopy, energy dispersive X-ray spectra, cyclic voltammetry, and linear scanning voltammetry (LSV) were used to scrutinize the electrodes and the electrochemical activity. The experimental results indicate that solvothermal crystallization in the presence of hydrochloric acid plays a critical role in regulating the catalyst size and microstructure during the nucleation and growth process of RuO-TiO. The designed RuO-TiO/Ti anode with a nano-flowerlike structure displays significantly enhanced activity toward anodic chlorine evolution reaction (CER) compared to the other two morphology anodes. Such excellent performance of RuO-TiO/Ti is explained in terms of the small charge transfer resistance and the unique surface structure with more active sites to be utilized during CER. Graphical abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

We recently found lytic action of the truncated yncE gene. When the truncated yncE gene of Salmonella enterica serovar Paratyphi A was expressed in Escherichia coli DH5α under the control of the Ara promoter, bacterial growth was markedly inhibited. In the present study, we characterized this lytic action. The N-terminal 103 aa of YncE, containing a signal peptide, was demonstrated to be essential for inhibition. Microscopic observation showed that the bacterial envelope of E. coli was damaged by the expression of truncated yncE, resulting in the release of cytoplasmic content and the formation of bacterial ghosts. The addition of MgSO or spermine, which is the stabilizer of bacterial membrane structure, dramatically reversed the cell lysis induced by the toxic truncated YncE. In contrast, the lytic action was significantly enhanced by the addition of SDS or EDTA. Our data indicated that the toxic truncated YncE could cause cell lysis by the disruption of the bacterial membrane. [ABSTRACT FROM AUTHOR]

The (RuTiSnSb)O-TiO nanotubes (TNTs) anode has been prepared via anodization, deposition, and annealing. X-ray diffraction, field-emission scanning electron microscopy, cyclic voltammetry, and linear scanning voltammetry were used to scrutinize the electrodes and the electrochemical activity. The results indicate that highly ordered TNTs with large specific surface area could be implanted with active metal oxides. The catalyst firmly binds with the TNTs and enhances the electrochemical stability of the electrode. It displays high over-potential for oxygen evolution reaction. Accordingly, the constructed (RuTiSnSb)O-TNTs anode exhibits a greater potential difference (Δ E) between the evolutions of oxygen and chlorine than that exhibited by the traditional dimensionally stable anode, which is beneficial for improving the selectivity toward chlorine evolution reaction. This superior performance is explained in terms of the surface properties and geometric structure of coated catalyst, as well as the electrochemical selectivity ascribed by the addition of tin and antimony species. [ABSTRACT FROM AUTHOR]

Lithium (Li)-bearing clays have become new types of Li resources, and it is found that the evolution of the mineral structure in Li-bearing clay greatly restricts the extraction of Li. Herein, a Li-bearing clay from Guizhou Province, China, was studied using in situ thermogravimetry–differential scanning calorimetry–mass spectrometry–Fourier transform infrared spectroscopy (TG–DSC–MS–FTIR) (evolved gases), 27Al and 1H magic-angle spinning nuclear magnetic resonance (MAS NMR), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The results showed that the Li-bearing clay contained illite, chlorite, kaolinite, pyrite, and anatase. The dehydroxylation reaction of the clay minerals occurred at 450 °C. CH2, CH4, C3H4, C6H5, and C8H9 evolved during the roasting process. The AlO4(OH)2 octahedra transformed to AlO4 tetrahedra due to the reaction between the reductive gases and the residual O in AlO5. The effect of dehydroxylation on the structural stability of different clay minerals differed. After dehydroxylation, kaolinite became amorphous, chlorite reacted with 20% H2SO4, and illite remained stable during the roasting-H2SO4 leaching process. The Li-leaching efficiency increased significantly after dehydroxylation and decreased sharply with the formation of mullite. [ABSTRACT FROM AUTHOR]

Glaucoma is a group of diseases characterized by the degeneration of retinal ganglion cells (RGCs) and progressive, irreversible vision loss. High intraocular pressure (IOP) heightens the likelihood of glaucoma and correlates with RGC loss. While the current glaucoma therapy prioritizes lower the IOP; however, RGC, and visual loss may persist even when the IOP is well-controlled. As such, discovering and creating IOP-independent neuroprotective strategies for safeguard RGCs is crucial for glaucoma management. Investigating and clarifying the mechanism behind RGC death to counteract its effects is a promising direction for glaucoma control. Empirical studies of glaucoma reveal the role of multiple regulated cell death (RCD) pathways in RGC death. This review delineates the RCD of RGCs following IOP elevation and optic nerve damage and discusses the substantial benefits of mitigating RCD in RGCs in preserving visual function. [ABSTRACT FROM AUTHOR]

The magnetoelastic behaviour subjected to the electromagnetic body force induced by flux pinning is studied with Kim model for zero-field cooling (ZFC) magnetization process, in which the non-uniform parameter η is considered for inclusion-superconducting matrix system. For superconducting composites, the effect of inhomogeneous distribution of critical current density on effective magnetostriction is also obtained based on the plane strain approach. The results show that the exponential distribution of critical-current density will lead to a larger trapped field and magnetostriction inside the inhomogeneous sample, which also means that it is worthwhile to investigate the magnetoelastic problem of bulk superconductors with inhomogeneous distribution of critical-current density. [ABSTRACT FROM AUTHOR]

During an educational dissection of a 72-year-old Chinese male cadaver, the hemiazygos vein (HAV) coursing the left side that drains into the persistent left superior vena cava was observed. The HAV was formed at the junction of the 9th to 11th right posterior intercostal veins, right subcostal vein, 5th to 11th left posterior intercostal veins, and left subcostal vein; it then ascended posteriorly to the thoracic aorta. After collecting the accessory hemiazygos vein, it crossed over the aorta and the pedicle of the left lung via the hemiazygos arch, then converged with a communicative branch (vein of Marshall) that emerged from the left brachiocephalic vein to form the persistent left superior vena cava and entered the pericardium at the level of the sixth thoracic vertebra. Upon opening the pericardium of our cadaver, the persistent left superior vena cava was found to drain directly into the significantly dilated coronary sinus at the level of the eighth thoracic vertebra. The azygos vein was formed by the union of the first to eighth right posterior intercostal veins and appeared to be finer and shorter than the HAV. The persistent left superior vena cava might be the result of incomplete degeneration of the left posterior cardinal vein. Knowledge of such variations could be of great value to surgeons placing peripherally inserted central catheters because incorrect placement of the azygos venous system can be detrimental to the patient. In addition, during heart surgery, awareness of such variations may prevent major complications, such as hemorrhage or damage to vascular structures, and possibly also provide new insights and perspectives to cardiovascular surgeries. [ABSTRACT FROM AUTHOR]

N-acetyl-leucyl-leucyl-norleucinal (ALLN), an inhibitor of proteasomes and calpain, is widely used to reduce proteasomes or calpain-mediated cell death in rodents. However, ALLN is toxic to retinal neurons to some extent. At the concentration of 10 μM, ALLN is non-toxic to cortical neurons, but induces cell death of retinal neurons in vitro. The tolerance concentration of ALLN for retinal neurons is unclear, and the precise mechanism of cell death induced by ALLN remains elusive. In this study, we investigated the toxic effect of ALLN on primary retinal neurons. The 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed no significant changes of cell viability at 1 μM but decreased cell viability after treatment of ALLN at 2.5, 5, and 7.5 μM. Lactate dehydrogenase (LDH) release was highly elevated and propidium iodide (PI)-positive cells were significantly increased at 2.5, 5, and 7.5 μM after all treatment times. Moreover, the protein levels of caspase-3 were up-regulated at 5 and 7.5 μM after 12 and 24 h of ALLN treatment. The ratio of Bax/Bcl-2 was raised and Annexin V-positive cells were increased at 5 and 7.5 μM after 12 and 24 h of ALLN treatment. However, there were no significant changes in either the ratio of microtubule-associated protein 1 light chain 3 (LC3) II/LC3 I or monodansylcadaverine (MDC) staining. Our data clearly show that at the concentrations equal to and higher than 2.5 μM, ALLN may induce cell death of primary retinal neurons by necrosis and apoptosis, but not autophagy. These suggest that primary retinal neurons are more susceptible to ALLN treatment and provide a possible mechanism for the cell death of ALLN-sensitive cells in ALLN injury. [ABSTRACT FROM AUTHOR]

The aim of this study is to characterize plutonium sorption particularly Pu distribution coefficients and the influence of pH on sorption processes in saturated geological materials used as a radioactive waste repository in China. The examined geological media is from a southwestern Chinese repository and consists of soil and slates. The backfill material consists of Na-bentonite from Inner Mongolia Gaomiaozi, and will be used at the Beishan high-level waste (HLW) repository, Gansu Province. The results show that the sorption capacity of Pu by geological medium in an acidic environment is low, but significantly increases with increasing pH. [ABSTRACT FROM AUTHOR]

As a new surgical technique, 'one-stop hybrid procedure' is rarely applied in trauma patients. This paper aims to explore its role in vascular injury of the lower extremity. Vascular intervention combined with open surgery was performed to treat three cases of vessel injuries of the lower extremity in our hybrid operating room. One patient with stab injury to the left femoral vein was treated by temporary artery blocking after excluding arterial injury by angiography, followed by blocking surgery and debridement and repair of the injured vein. The other two patients with drug addiction history, who were found to have pricking injuries to the femoral artery combined with local infection, were successfully treated by endovascular techniques and open debridement. One-stop hybrid procedure in treating vascular injury patients could simplify the operation procedure, reduce operative risk, and achieve good curative effect. [ABSTRACT FROM AUTHOR]