Freeze Metal Halide Perovskite for Dramatic Laser Tuning: Direct Observation via In Situ Cryo-Electron Microscope.

A frozen-temperature (below -28 °C) laser tuning way is developed to optimize metal halide perovskite (MHP)'s stability and opto-electronic properties, for emitter, photovoltaic and detector applications. Here freezing can adjust the competitive laser irradiation effects between damaging and annealing/repairing. And the ligand shells on MHP surface, which are widely present for many MHP materials, can be frozen and act as transparent solid templates for MHP's re-crystallization/re-growth during the laser tuning. With model samples of different types of CsPbBr3 nanocube arrays,an attempt is made to turn the dominant exposure facet from low-energy [100] facet to high-energy [111], [-211], [113] and [210] ones respectively; selectively removing the surface impurities and defects of CsPbBr3 nanocubes to enhance the irradiation durability by 101 times; and quickly (tens of seconds) modifying a Ruddlesden-Popper (RP) boundary into another type of boundary like twinning, and so on. The laser tuning mechanism is revealed by an innovative in situ cryo-transmission electron microscope (cryo-TEM) exploration at atomic resolution.

Efficient photodegradation of antibiotics by g-C3N4 and 3D flower-like Bi2WO6 perovskite structure: Insights into the preparation, evaluation, and potential mechanism.

Antibiotics are emerging organic pollutants that have attracted huge attention owing to their abundant use and associated ecological threats. The aim of this study is to develop and use photocatalysts to degrade antibiotics, including tetracycline (TC), ciprofloxacin (CIP), and amoxicillin (AMOX). Therefore, a novel Z-scheme heterojunction composite of g-C3N4 (gCN) and 3D flower-like Bi2WO6 (BW) perovskite structure was designed and developed, namely Bi2WO6/g-C3N4 (BW/gCN), which can degrade low-concentration of antibiotics in aquatic environments under visible light. According to the Density Functional Theory (DFT) calculation and the characterization results of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FITR), Scanning electron microscopy - energy spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS), this heterojunction was formed in the recombination process. Furthermore, the results of 15 wt%-BW/gCN photocatalytic experiments showed that the photodegradation rates (Rp) of TC, CIP, and AMOX were 92.4%, 90.1% and 82.3%, respectively, with good stability in three-cycle photocatalytic experiments. Finally, the quenching experiment of free radicals showed that the holes (h+) and superoxide radicals (·O2-) play a more important role than the hydroxyl radicals (·OH) in photocatalysis. In addition, a possible antibiotic degradation pathway was hypothesized on the basis of High performance liquid chromatography (HPLC) analysis. In general, we have developed an effective catalyst for photocatalytic degradation of antibiotic pollutants and analyzed its photocatalytic degradation mechanism, which provides new ideas for follow-up research and expands its application in the field of antibiotic composite pollution prevention and control.

Portulaca oleracea exhibited anti-coccidian activity, fortified the gut microbiota of Hu lambs.

Coccidia of the genus Eimeria are important pathogens that cause coccidiosis in livestock and poultry. Due to the expansion of intensive farming, coccidiosis has become more difficult to control. In addition, the continued use of anti-coccidiosis drugs has led to drug resistance and residue. Some herbs used in traditional Chinese medicine (TCM) have been shown to alleviate the clinical symptoms of coccidiosis, while enhancing immunity and growth performance (GP) of livestock and poultry. Previous in vitro and in vivo studies have reported that the TCM herb Portulaca oleracea exhibited anti-parasitic activities. In total, 36 female Hu lambs were equally divided into six treatment groups: PL (low-dose P. oleracea), PH (high-dose P. oleracea), PW (P. oleracea water extract), PE (P. oleracea ethanol extract), DIC (diclazuril), and CON (control). The treatment period was 14 days. The McMaster counting method was used to evaluate the anti-coccidiosis effects of the different treatments. Untargeted metabolomics and 16S rRNA gene sequencing were used to investigate the effects of treatment on the gut microbiota (GM) and GP. The results showed that P. oleracea ameliorated coccidiosis, improved GP, increased the abundances of beneficial bacteria, and maintained the composition of the GM, but failed to completely clear coccidian oocysts. The Firmicutes to Bacteroides ratio was significantly increased in the PH group. P. oleracea increased metabolism of tryptophan as well as some vitamins and cofactors in the GM and decreased the relative content of arginine, tryptophan, niacin, and other nutrients, thereby promoting intestinal health and enhancing GP. As an alternative to the anti-coccidiosis drug DIC, P. oleracea effectively inhibited growth of coccidia, maintained the composition of the GM, promoted intestinal health, and increased nutrient digestibility.

Analyzing the effect of public private partnership mode on sewage treatment in China.

The public-private partnership (PPP) mode is one of the main ways to promote environmental governance through marketization in the sewage treatment industry. This mode is crucial for environmental protection and livelihood improvement. In order to investigate the impact of PPP mode on sewage treatment, the influence of financial development and the government-business relationship on the effectiveness of sewage treatment under PPP mode, and the role of government in this context, an empirical model is established. To achieve this, data from 284 prefecture-level and above cities in China from 2009 to 2017 has been selected as research samples. The total amount of regional sewage treatment PPP projects is used as the proxy variable for participation in the PPP mode. The findings reveal that the PPP mode of sewage treatment effectively reduces the intensity and amount of sewage discharge. Moreover, the results indicate that a higher level of financial development and a more perfect financial system are associated with better sewage treatment effects under the PPP mode. Similarly, a more harmonious government-business relationship and a higher health index of this relationship correspond to improved sewage treatment effects under the PPP mode. The government should actively enhance government transparency, formulate appropriate corporate taxes and fees, clarify the responsibilities and obligations of the government and enterprises, and optimize the business environment in order to optimize the sewage treatment effect of the PPP mode.

Engineering Two-Dimensional Metal-Organic Framework on Molecular Basis for Fast Li+ Conduction.

Metal-organic frameworks (MOFs) have been proposed as emerging fillers for composite polymer electrolytes (CPEs). However, MOF particles are usually served as passive fillers that yield limited ionic conductivity improvement. Building continuous MOF reinforcements and exploiting their active roles remain challenging. Here we demonstrate the feasibility of engineering fast Li+ conduction within MOF on molecule conception. Two-dimensional Cu(BDC) MOF is selected as an active filler due to its sufficient accessible open metal sites for perchlorate anion anchoring to release free Li+, verified by theoretical calculations and measurements. A novel Cu(BDC)-scaffold-reinforced CPE is developed via in situ growth of MOF, which provides fast Li+ channels inside MOF and continuous Li+ paths along the MOF/polymer interface for high Li+ conductivity (ambient 0.24 mS cm-1) and enables high mechanical strength. Stable cycling is achieved in solid-state Li-NCM811 full cell using the MOF-reinforced CPE. This molecule-basis Li+ conduction strategy brings new ideas for designing advanced CPEs.

PD-L1 tumor-intrinsic signaling and its therapeutic implication in triple-negative breast cancer.

Although the immune checkpoint role of programmed death ligand 1 (PD-L1) has been established and targeted in cancer immunotherapy, the tumor-intrinsic role of PD-L1 is less appreciated in tumor biology and therapeutics development, partly because of the incomplete mechanistic understanding. Here we demonstrate a potentially novel mechanism by which PD-L1 promotes the epithelial-mesenchymal transition (EMT) in triple-negative breast cancer (TNBC) cells by suppressing the destruction of the EMT transcription factor Snail. PD-L1 directly binds to and inhibits the tyrosine phosphatase PTP1B, thus preserving p38-MAPK activity that phosphorylates and inhibits glycogen synthase kinase 3ß (GSK3ß). Via this mechanism, PD-L1 prevents the GSK3ß-mediated phosphorylation, ubiquitination, and degradation of Snail and consequently promotes the EMT and metastatic potential of TNBC. Significantly, PD-L1 antibodies that confine the tumor-intrinsic PD-L1/Snail pathway restricted TNBC progression in immunodeficient mice. More importantly, targeting both tumor-intrinsic and tumor-extrinsic functions of PD-L1 showed strong synergistic tumor suppression effect in an immunocompetent TNBC mouse model. Our findings support that PD-L1 intrinsically facilitates TNBC progression by promoting the EMT, and this potentially novel PD-L1 signaling pathway could be targeted for better clinical management of PD-L1-overexpressing TNBCs.

The Role of Polymer and Inorganic Coatings to Enhance Interparticle Connections Diagnosed by In Situ Techniques.

Surface coating on alloy anodes renders an effective remedy to tolerate internal stress and alleviate the side reaction with electrolytes for long-lasting reversible lithium redox reactions in lithium-ion batteries. However, the role of surface coating on the interparticle connections of alloy anodes remains not fully understood. Herein, we exploit real-time lithiation and mechanic measurement of SnO2 nanoparticles via in situ TEM with different coating layers, including conducting polymer polypyrrole and metal oxide MnO2. As a result, polypyrrole is more flexible to accommodate the volume expansion issue. More importantly, the polypyrrole coating layers offer a large contact area and strong adhesion force between the SnO2 nanoparticles, ensuring fast lithiation kinetics and high cycling stability. These observations provide new insight into how the interparticle connections of alloy anodes with diverse coating approaches can impact battery performance, shedding light on the practical processing of the alloy anode materials for high-energy Li-ion batteries.

Three-Dimensional-Percolated Ceramic Nanoparticles along Natural-Cellulose-Derived Hierarchical Networks for High Li+ Conductivity and Mechanical Strength.

Solid polymer electrolytes for safe lithium batteries are in general flexible and easy to process, yet they have limited ionic conductivity and low mechanical strength. Introducing nano/microsized fillers into polymer electrolytes has been proven effective to address these issues, while formation of a percolated network of fillers for efficient Li+ conduction remains challenging. In this work, composite polymer electrolyte with 3D cellulose/ceramic networks is successfully developed using natural cellulose fibers and Li+-conducting ceramic nanoparticles. Monodisperse ceramic nanofillers first form interconnected networks driven by the self-assembly of hybrid cellulose fibers. The hierarchical cellulose skeleton provides spatial guidance for ceramic fillers and firmly supports the whole structure. After polymer electrolyte infusion, the resultant hybrid electrolyte affords both 3D continuous Li+ pathways for high Li+ conductivity and sufficient mechanical strength for dendrite suppression. This cellulose-confined particle percolation approach enables efficient and strong solid electrolytes for lithium batteries.

Li+ -Containing, Continuous Silica Nanofibers for High Li+ Conductivity in Composite Polymer Electrolyte.

Solid-state electrolytes have recently attracted significant attention toward safe and high-energy lithium chemistries. In particular, polyethylene oxide (PEO)-based composite polymer electrolytes (CPEs) have shown outstanding mechanical flexibility and manufacturing feasibility. However, their limited ionic conductivity, poor electrochemical stability, and insufficient mechanical strength are yet to be addressed. In this work, a novel CPE supported by Li+ -containing SiO2 nanofibers is developed. The nanofibers are obtained via sol-gel electrospinning, during which lithium sulfate is in situ introduced into the nanofibers. The uniform doping of Li2 SO4 in SiO2 nanofibers increases the Li+ conductivity of SiO2 , generates mesopores on the surface of SiO2 nanofibers, and improves the wettability between SiO2 and PEO. As a result, the obtained SiO2 /Li2 SO4 /PEO CPE yields high Li+ conductivity (1.3 × 10-4 S cm-1 at 60 °C, ≈4.9 times the Li2 SO4 -free CPE) and electrochemical stability. Furthermore, the all-solid-state LiFePO4 -Li full cell demonstrates stable cycling with high capacities (over 80 mAh g-1 , 50 cycles at C/2 at 60 °C). The Li+ -containing mesoporous SiO2 nanofibers show great potential as the filler for CPEs. Similar methods can be used to incorporate Li salts into other filler materials for CPEs.

Type Iγ phosphatidylinositol phosphate kinase dependent cell migration and invasion are dispensable for tumor metastasis.

Type Iγ phosphatidylinositol phosphate kinase (PIPKIγ) has been associated with poor prognosis in breast cancer patients by promoting metastasis. Among the six alternative-splicing isoforms of PIPKIγ, PIPKIγ_i2 specifically targets to focal adhesions and regulates focal adhesion turnover, thus was proposed responsible for tumor metastasis. In the present study, we specifically depleted PIPKIγ_i2 from mouse triple negative breast cancer (TNBC) 4T1 cells and analyzed their behaviors. As expected, PIPKIγ_i2-depleted 4T1 cells exhibited reduced proliferation, migration, and invasion in vitro at a comparable level as pan-PIPKIγ depleted cells. However, PIPKIγ_i2 depletion had no effect on metastasis and progression of 4T1 tumors in vivo. PIPKIγ_i2-depleted tumors showed similar levels of growth, hypoxia state, macrophage infiltration, and angiogenesis as parental tumors, although the pan-PIPKIγ depletion led to substantial inhibition on these aspects. Further investigation revealed that depleting PIPKIγ_i2 alone, unlike depleting all PIPKIγ isoforms, had no effect on PD-L1 expression, the status of the epithelial-to-mesenchymal transition, and the anchorage-independent growth of 4T1 cells. In human TNBC MDA-MB-231 cells, we obtained similar results. Thus, while PIPKIγ_i2 indeed is required for cell migration and invasion, these characteristics are not decisive for metastasis. Other PIPKIγ isoform(s) that regulate the expression of key factors to support cell survival under stresses is more critical for the malignant progression of TNBCs.

Thermal Lithiated-TiO2: A Robust and Electron-Conducting Protection Layer for Li-Si Alloy Anode.

Developing new electrode materials with high capacity and stability is an urgent demand in electric vehicle applications. Li xSi alloy, as a promising high-capacity and Li-containing anode candidate, has attracted much attention. However, the alloy anode suffers severely from intrinsic high chemical reactivity and poor cycling stability in battery fabrication and operation. Here, we have developed a facile coating-then-lithiation approach to prepare lithiated-TiO2 protected Li xSi nanoparticles (Li xSi-Li2O/Ti yO z NPs) as an attractive anode material. The robust lithiated-TiO2 protection matrix not only provides fast electron transport pathways to efficiently improve the electrical conductivity between Li xSi/Si NPs, but also spatially limits the direct solid electrolyte interphase formation on Li xSi/Si cores during cycling. More importantly, this dense coating layer protects most inner Li xSi alloys from ambient corrosion, leading to high dry-air stability. As a result, the resulting Li xSi-Li2O/Ti yO z anode achieves greatly enhanced cycling and chemical stability in half-cells. It maintains capacity of about 1300 mAh g-1 after prolonged 500 cycles at a high current rate of C/2, with 77% capacity retention. In addition, it exhibits excellent dry-air stability, with around 87% capacity retained after exposure to dry air (10% relative humidity) for 30 days.

Assembly of LiMnPO4 Nanoplates into Microclusters as a High-Performance Cathode in Lithium-Ion Batteries.

A novel structure of a carbon-coated LiMnPO4 microcluster through emulsion-based self-assembly has been fabricated to yield a high-performance battery cathode. In this rational design, nanosized LiMnPO4 plates are assembled into microclusters to achieve a dense packing and robust interparticle contact. In addition, the conductive carbon framework wrapping around these clusters functions as a fast electron highway, ensuring the high utilization of the active materials. The designed structure demonstrates enhanced specific capacity and cycling stability in lithium-ion batteries, delivering a discharge capacity of 120 mAh g-1 after 200 cycles at 0.2 C. It also shows a superior rate capability with discharge capacities of 139.7 mAh g-1 at 0.05 C, 131.7 mAh g-1 at 0.1 C, and 99.2 mAh g-1 at 1 C at room temperature.

[Development of a computer-aided system for augmentation mammaplasty simulation].

A method for developing a three-dimensional visual system for simulating augmentation mammaplasty based on OpenGL is proposed. The 3D reconstruction of breast surface using NURBS, reality simulation of the breast surface, parametric design of mammary prosthesis, and simulation of postoperative effect are described. The system may provide a means for better communication between the surgeons and patients.

[A study of making use of computer-aided projection fringe system to measure breast dimension].

OBJECTIVE: To measure breast basic dimension by using computer-aided projection fringe system. METHODS: A system has been developed for measuring breast basic dimension based on computer-aided projection fringe measurement and programming software. Plastic manikins breast's SN-N (sternal notch to nipple distance), N-ML (nipple to midline distance), N-N (internipple distance), MBW (base width of breast) and N-IMF (nipple to inframammary fold distance) are measured with this system. At the same time, these items are also measured with routine ruler. RESULTS: This study indicate that the system has some merits: (1) non-touching measurement; (2) it is very rapid, the patient measured need hold his breath only 0.5 second, and all the time it takes is about 2.5 minutes; (3) the measurement's sensitivity is as high as to 0.6 mm, which meets the clinic requirement entirely; (4) the measurement's accuracy of the system is not significantly when comparing to the routine ruler's. CONCLUSIONS: Computer-aided projection fringe system for measuring breast basic dimension is feasible and advanced.

[Three-dimensional breast non-contact measurement].

OBJECTIVE: To develop a system for three-dimensional (3D) non-contact measurement of breast using computer-aided projection fringe measurement (CAPFM). METHODS: A system of 3D non-contact breast measurement was developed based on CAPFM and used for measurement of a plastic model mimicking human breast. RESULTS: The CAPFM system was capable of non-contact 3D measurement with rapid data collection (within 0.5 s) and measurement (no longer than -3 min). This system was highly automatic, and with software-controlled measurement, the sensitivity was as high as 0.6 mm (for linear measurement) and 1 ml (for volume measurement), to well meet the clinical requirements. The measurement results could be stored and expressed in numerical values or represented in vivid 2D figures and 3D images, which facilitated subsequent studies. CONCLUSION: The 3D non-contact breast measurement system on the basis of CAPFM can be helpful for medical assessment of the breast.