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Harmful algal blooms (HABs) in natural waters are of escalating global concern due to their detrimental impact on environmental health. Emerging evidence indicates that algae-bacteria symbionts can affect HAB features, though much about this interplay remains largely unexplored. The current study isolated a new species of Mucilaginibacter (type strain JXJ CY 39T) from culture biomass of the bloom-causing Microcystis aeruginosa FACHB-905 (Maf) from Lake Dianchi, China. Strain JXJ CY 39T was an aerobic, Gram-stain-negative rod bacterium that grew at 5–38°C, pH 4.0–11.0, and 0–3.0% NaCl. Taxonomic evaluation proposed a new species, with Mucilaginibacter lacusdianchii sp. nov., as the species epithet. Experimental results revealed that strain JXJ CY 39T spurred the growth of Maf by supplying soluble phosphorus and nitrogen during cultivation, despite the unavailability of soluble phosphorus and nitrogen. Additionally, by producing the plant hormone indole-3-acetate, strain JXJ CY 39T possibly impacted Maf’s functionality. Results from co-culture experiments with other strains from Maf biomass showed possible effects of strain JXJ CY 39T on the relationship between Maf and other cohabiting bacteria, as well as microcystin toxin production characteristics. Although Maf could foster the growth of strain JXJ CY 39T by supplying organic carbon, the strain’s growth could be regulated via specific chemical compounds based on antibiotic assays. Community composition analysis disclosed that this Mucilaginibacter strain positively affected Maf’s growth and modified densities and types of bacteria linked to Maf. Overall, these results suggest that the interactions between important HAB-causing organisms and their attached bacteria are complex, dynamic, and may influence the growth characteristics of algae.

Compared to SnTe and PbTe base materials, the GeTe matrix exhibits a relatively high Seebeck coefficient and power factor but has garnered significant attention due to its poor thermal transport performance and environmental characteristics. As a typical p-type IV–VI group thermoelectric material, W-doped GeTe material can bring additional enhancement to thermoelectric performance. In this study, the introduction of W, Ge1−xWxTe (x = 0, 0.002, 0.005, 0.007, 0.01, 0.03) resulted in the presence of high-valence state atoms, providing additional charge carriers, thereby elevating the material’s power factor to a maximum PFpeak of approximately 43 μW cm−1 K−2, while slightly optimizing the Seebeck coefficient of the solid solution. Moreover, W doping can induce defects and promote slight rhombohedral distortion in the crystal structure of GeTe, further reducing the lattice thermal conductivity κlat to as low as approximately 0.14 W m−1 K−1 (x = 0.002 at 673 K), optimizing it to approximately 85% compared to the GeTe matrix. This led to the formation of a p-type multicomponent composite thermoelectric material with ultra-low thermal conductivity. Ultimately, W doping achieves the comprehensive enhancement of the thermoelectric performance of GeTe base materials, with the peak ZT value of sample Ge0.995W0.005Te reaching approximately 0.99 at 673 K, and the average ZT optimized to 0.76 in the high-temperature range of 573–723 K, representing an increase of approximately 17% compared to pristine GeTe within the same temperature range.

Sodium-ion batteries (SIBs) have demonstrated remarkable development potential and commercial prospects. However, in the current state of research, the development of high-energy-density, long-cycle-life, high-rate-performance anode materials for SIBs remains a huge challenge. Free-standing flexible electrodes, owing to their ability to achieve higher energy density without the need for current collectors, binders, and conductive additives, have garnered significant attention across various fields. In this work, we designed and fabricated a free-standing three-dimensional flexible Nb2O5@WS2@C carbon nanofiber (CNF) anode based on a hybrid adsorption–intercalation–conversion mechanism of sodium storage, using electrospinning and hydrothermal synthesis processes. The hybrid structure, aided by synergistic effects, releases the advantages of all materials, demonstrating a superior rate performance (288, 248, 211, 158, 90, and 48 mA h g−1 at the current density of 0.2, 0.5, 1, 2, 5, and 10 A g−1, respectively) and good cycling stability (160 mA h g−1 after 200 cycles at 1 A g−1). This work provides certain guiding significance for future research on hybrid and flexible anodes of SIBs.

Rapid and accurate assessment of fracture permeability is critical for subsurface resource and energy development as well as rock engineering stability. Fracture permeability deviates from the classical cubic law under the effect of roughness, geological stress, as well as mining-induced stress. Conventional laboratory tests and numerical simulations are commonly costly and time-consuming, whereas the use of a connectivity metric based on percolation theory can quickly predict fracture permeability, but with relatively low accuracy. For this reason, we selected two static connectivity metrics with the highest and lowest prediction accuracy in previous studies, respectively, and proposed to revise and use them for fracture permeability estimation, considering the effect of isolated large-aperture regions within the fractures under increasing normal stress. Several hundred fractures with different fractal dimensions and mismatch lengths were numerically generated and deformed, and their permeability was calculated by the local cubic law (LCL). Based on the dataset, the connectivity metrics were counted using the revised approach, and the results show that, regardless of the connectivity metrics, the new model greatly improves the accuracy of permeability prediction compared to the pre-improved model, by at least 8% for different cutoff aperture thresholds.

Developing high-performance anodes is one of the most effective ways to improve the energy storage performances of potassium-ion batteries (PIBs). Among them, Ti-based oxides, including TiO2, K2Ti6O13, K2Ti4O9, K2Ti8O17, Li4Ti5O12, etc., as the intrinsic structural advantages, are of great interest for applications in PIBs. Despite numerous merits of Ti-based oxide anodes, such as fantastic chemical and thermal stability, a rich reserve of raw materials, non-toxic and environmentally friendly properties, etc., their poor electrical conductivity limits the energy storage applications in PIBs, which is the key challenge for these anodes. Although various modification projects are effectively used to improve their energy storage performances, there are still some related issues and problems that need to be addressed and solved. This review provides a comprehensive summary on the latest research progress of Ti-based oxide anodes for the application in PIBs. Besides the major impactful work and various performance improvement strategies, such as structural regulation, carbon modification, element doping, etc., some promising research directions, including effects of electrolytes and binders, MXene-derived TiO2-based anodes and application as a modifier, are outlined in this review. In addition, noteworthy research perspectives and future development challenges for Ti-based oxide anodes in PIBs are also proposed.

Using natural light energy to convert water into hydrogen is of great significance to solving energy shortages and environmental pollution. Due to the rapid recombination of photogenerated carriers after separation, the efficiency of photocatalytic hydrogen production using photocatalysts is usually very low. Here, efficient CdZnS nanoparticles@Ti3C2Tx MXene nanosheet heterojunction photocatalysts have been successfully prepared by a facile in situ growth strategy. Since the CdZnS nanoparticles uniformly covered the Ti3C2Tx Mxene nanosheets, the agglomeration phenomenon of CdZnS nanoparticles could be effectively inhibited, accompanied by increased Schottky barrier sites and an enhanced migration rate of photogenerated carriers. The utilization efficiency of light energy can be improved by inhibiting the recombination of photogenerated electron-hole pairs. As a result, under the visible-light-driven photocatalytic experiments, this composite achieved a high hydrogen evolution rate of 47.1 mmol h−1 g−1, which is much higher than pristine CdZnS and Mxene. The boosted photocatalytic performances can be attributed to the formed heterojunction of CdZnS nanoparticles and Ti3C2Tx MXene nanosheets, as well as the weakened agglomeration effects.

Aim: Aseptic meningitis is an unfortunate complication after craniotomy. Continuous lumbar drainage is a safe and effective method for treating postcraniotomy aseptic meningitis. This study compared the incidence of cerebrospinal fluid (CSF) leakage around the tube at the skin exit site and infection associated with tubes placed in two different ways. Patients and Methods: The study enrolled 140 consecutive patients with postoperative aseptic meningitis manifesting as headache and fever and managed by lumbar external drainage (LED) between June 2014 and July 2018. From June 2014 to Jan 2016, an LED catheter was set in a conventional fashion without a subcutaneous tunnel. From Feb 2016 to July 2018, we adopted a modified mode of placing the LED catheter with a subcutaneous tunnel. Drain-related CSF leakage and infection were analyzed between the two groups. Results: Postoperative aseptic meningitis can be easily managed through lumbar CSF drainage. The incidences of drain-associated infection and CSF leakage were 20% and 7.14%, respectively, in group 1 (without subcutaneous tunnels) and 7.14% and 4.28%, respectively, in group 2 (with subcutaneous tunnels). CSF leakage was significantly reduced in group 2 compared to group 1 (P

Abstract Copper ferrites are emerging transition metal oxides that have potential applications in energy storage devices. However, it still lacks in-depth designing of copper ferrites based anode architectures with enhanced electroactivity for lithium-ion batteries. Here, we report a facile synthesis technology of copper ferrites anchored on reduced graphene oxide (CuFeO2@rGO and Cu/CuFe2O4@rGO) as the high-performance electrodes. In the resulting configuration, reduced graphene offers continuous conductive channels for electron/ion transfer and high specific surface area to accommodate the volume expansion of copper ferrites. Consequently, the sheet-on-sheet CuFeO2@rGO electrode exhibits a high reversible capacity (587 mAh g−1 after 100 cycles at 200 mA g−1). In particular, Cu/CuFe2O4@rGO hybrid, which combines the advantages of nano-copper and reduced graphene, manifests a significant enhancement in lithium storage properties. It reveals superior rate capability (723 mAh g−1 at 800 mA g−1; 560 mAh g−1 at 3200 mA g−1) and robust cycling capability (1102 mAh g−1 after 250 cycles at 800 mA g−1). This unique structure design provides a strategy for the development of multivalent metal oxides in lithium storage device applications.

Abstract Two-dimensional layered K4Nb6O17 (KN) was easily formed as a secondary phase caused by the volatilization of alkali metal ions, when preparing ferroelectric K x Na1−x NbO3 based ceramics and films. In this work, it was believed that KN film is with weak ferroelectricity and has a little effect on the ferroelectric properties of K x Na1−x NbO3 based films. Moreover, temperature dependent (77–500 K) dielectric functions of KN film have been firstly extracted by fitting ellipsometric spectra with the Adachi dielectric function model and a four-phase layered model. The high-frequency dielectric constant linearly increases and optical band gap slightly decreases with increasing the temperature. We also research its photoelectrochemical properties and its application in high-efficient light-induced H2 evolution. In addition, X-ray photoelectron spectroscopy, Raman scattering, temperature dependent transmittance and infrared reflectance spectra, and first-principles calculation were conjointly performed to further reveal the intrinsic optoelectronic features and relevant mechanisms of KN.

At present, Hepatocarcinoma is one of the main causes of tumor related death all over the world. However, there are still many clinical restrictions on the treatment of liver cancer. Recently, L-Selenocystine has been shown to be a novel treatment for tumors, especially human glioma cells. But, the mechanism of L-Selenocystine against hepatocellular carcinoma remains unclear. Therefore, the main objective of this study was to investigate the effects of L-Selenocystine on HepG2 cell proliferation and activation of reactive oxygen species (ROS) mediated signaling pathway. L-Selenocystine can significantly inhibit HepG2 cell proliferation by activating caspase-3 and cleaving PARP to induce apoptosis. Moreover, the excessive production of ROS and the influence of Bax signaling pathway which can promote cell apoptosis are key factors for L-Selenocystine to induce HepG2 cell apoptosis. Therefore, the date of this study suggest that ROS mediated signal transduction mechanism may provide certain reference significance for L-Selenocystine induced HepG2 cell apoptosis. [ABSTRACT FROM AUTHOR]

Due to the intrinsic low electrical conductivity and large volume expansion of the CoFe2O4 based active materials, designing more novel structures is still one of the most important challenges for its lithium ion battery application. In this work, the CoFe2O4/reduced graphene oxide/carbon (CFO/rGO/C) composite with integrated multi-layer structure has been synthesized through a facial two-step hydrothermal method. Benefiting from the introduction of the graphene network and amorphous carbon coating layer, as well as the accompanying synergistic effect, this composite can exhibit fast and reversible lithium intercalation/deintercalation reactions. With the aid of a surface-induced capacitive process, the CFO/rGO/C composite delivers a superior specific capacity (945 mA h g−1 at 0.1 A g−1) and excellent long-term cyclic stability (421 mA h g−1 at 4 A g−1 with closely 100% Coulombic efficiency after 2000 cycles). Significantly, at a high current density of 1 A g−1, the reversible capacity exhibits a rapid increasing after 100 cycles and finally shows an ultra-high-capacity of 1430 mA h g−1 over 500 cycles. This method could be generalized to the preparation of other similar transition metal oxide-based materials for the development of high-performance energy storage systems. [ABSTRACT FROM AUTHOR]

To overcome inferior rate capability and cycle stability of MnO-based anode materials for lithium-ion batteries (LIBs), we reported a novel 3D porous MnO@GS/CNT composite, consisting of MnO nanoparticles homogeneously distributed on the conductive interconnected framework based on 2D graphene sheets (GS) and 1D carbon nanotubes (CNTs). The distinctive architecture offers highly interpenetrated network along with efficient porous channels for fast electron transfer and ionic diffusion as well as abundant stress buffer space to accommodate the volume expansion of the MnO nanoparticles. The MnO@GS/CNT anode exhibits an ultrahigh capacity of 1115 mAh g−1 at 0.2 A g−1 after 150 cycles and outstanding rate capacity of 306 mAh g−1 at 10.0 A g−1. Moreover, a stable capacity of 405 mAh g−1 after 3200 cycles can still be achieved, even at a large current density of 5.0 A g−1. When coupled with LiMn2O4 (LMO) cathode, the LMO MnO@GS/CNT full cell characterizes an excellent cycling stability and rate capability, indicating the promising application of MnO@GS/CNT anode in the next-generation LIBs. [ABSTRACT FROM AUTHOR]

Orthorhombic Nb2O5 (T-Nb2O5) has structural merit but poor electrical conductivity, limiting their applications in energy storage. Although graphene is frequently adopted to effectively improve its electrochemical properties, the ordinary modified methods cannot meet the growing demands for high-performance. Here, we demonstrate that different graphene modified routes play a vital role in affecting the electrochemical performances of T-Nb2O5. By only manual shaking within one minute, Nb2O5 nano-particles can be rapidly adsorbed onto graphene, then the free-anchored T-Nb2O5@graphene three-dimensional networks can be successfully prepared based on hydrogel method. As for the application in lithium-ion batteries, it performs outstanding rate character (129 mA h g−1 (25C rate), 110 mA h g−1 (50C rate) and 90 mA h g−1 (100C rate), correspond to 79%, 67% and 55% capacity of 0.5C rate, respectively) and excellent long-term cycling feature (∼70% capacity retention after 20000 cycles). Moreover, it still maintains similar ultrafast-stable lithium storage performances when Cu foil is substituted by Al foil as current collector. In addition, relevant kinetics mechanisms are also expounded. This work provides a versatile strategy for the preparation of graphene modified Nb2O5 or other types of nanoparticles. [ABSTRACT FROM AUTHOR]