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The morphology of SNMs and PEGylated SNMs determined by TEM and DLS

Description of synthesis of compounds, additional experiments and procedures, and Table S1

Histological analysis of tumors and major organs

The therapeutic index for chemotherapeutic drugs is determined in part by systemic toxicity, so strategies for dose intensification to improve efficacy must also address tolerability. In addressing this issue, we have investigated a novel combinatorial strategy of reconstructing a drug molecule and using sequential drug-induced nanoassembly to fabricate supramolecular nanomedicines (SNM). Using cabazitaxel as a target agent, we established that individual synthetic prodrugs tethered with polyunsaturated fatty acids were capable of recapitulating self-assembly behavior independent of exogenous excipients. The resulting SNM could be further refined by PEGylation with amphiphilic copolymers suitable for preclinical studies. Among these cabazitaxel derivatives, docosahexaenoic acid–derived compound 1 retained high antiproliferative activity. SNM assembled with compound 1 displayed an unexpected enhancement of tolerability in animals along with effective therapeutic efficacy in a mouse xenograft model of human cancer, compared with free drug administered in its clinical formulation. Overall, our studies showed how attaching flexible lipid chains to a hydrophobic and highly toxic anticancer drug can convert it to a systemic self-deliverable nanotherapy, preserving its pharmacologic efficacy while improving its safety profile. Cancer Res; 77(24); 6963–74. ©2017 AACR.

Background The cisplatin resistance of non-small cell lung cancer (NSCLC) patients results in low response rate and overall survival rate. Exosomes contribute to pathological processes of multiple cancers. Objective In this study, we explored the function and mechanisms of exosomal miR-103a-3p derived from cancer-associated fibroblast (CAF) in cisplatin resistance in NSCLC. Results MiR-103a-3p was highly expressed in CAFs and CAF exosomes, and exosomal miR-103a-3p derived from CAFs in NSCLC. CAFs exosomes co-cultured with NSCLC cells promoted miR-103a-3p expression both in NSCLC cells and its exosomes. Functional experiments showed that exo-miR-103a-3p derived from CAFs promoted cisplatin resistance and inhibited apoptosis in NSCLC cells. Pumilio2 (Pum2) bound with miR-103a-3p in cytoplasm and nucleus, and facilitated packaging into CAF-derived exosomes in NSCLC cells. Further analysis showed Bak1 was a direct target of miR-103a-3p, and miR-103a-3p accelerated cisplatin resistance in NSCLC cells via Bak1 downregulation. In vivo tumorigenesis assay showed CAF-derived exosomal miR-103a-3p enhanced cisplatin resistance and inhibited cell apoptosis in NSCLC. Conclusion Our study revealed that CAFs-derived exosomal miR-103a-3p promoted cisplatin resistance by suppressing apoptosis via targeting Bak1, which provided a potential therapeutic target for cisplatin resistance in NSCLC.

Lithium sulfur (Li-S) batteries stand out among many new batteries for their high energy density. However, the intermediate charge–discharge product dissolves easily into the electrolyte to produce a shuttle effect, which is a key factor limiting the rapid development of Li-S batteries. Among the various materials used to solve the challenges related to pure sulfur cathodes, biomass derived carbon materials are getting wider research attention. In this work, we report on the fabrication of cathode materials for Li-S batteries based on composites of sulfur and biomass-derived porous ramie carbon (RC), which are coated with multiwalled carbon nanotubes (MWCNTs). RC can not only adsorb polysulfide in its pores, but also provide conductive channels. At the same time, the MWCNTs coating further reduces the dissolution of polysulfides into the electrolyte and weakens the shuttle effect. The sulfur loading rate of RC is 66.3 wt.%. As a result, the initial discharge capacity of the battery is 1325.6 mAh·g−1 at 0.1 C long cycle, and it can still maintain 812.5 mAh·g−1 after 500 cycles. This work proposes an effective double protection strategy for the development of advanced Li-S batteries.

Calix[4]quinone (C4Q) is a high-capacity organic cathode material, but its solubility in conventional organic electrolytes causes capacity decay, which leads to unavoidable restrictions in the practical application. Our previous research has revealed that the dissolution of C4Q can be effectively restricted by encapsulating it in CMK-3, but there is still room for improvement in its circulation performance and rate capability. Herein, we prepared a series of C4Q/CMK-3/SWCNT composites for sodium ion batteries (SIBs) by a facile deaerating–stirring method. The C4Q/CMK-3/SWCNT (40 wt%, 40 wt%, 10 wt%) cathode delivers a high and stable discharge capacity (290 mA h g−1) after 100 cycles at a current rate of 0.1 C. Even at a high rate of 1 C, its capacity is 346 mA h g−1. The stability and electronic conductivity of C4Q/CMK-3/SWCNTs are intensified by the three-dimensional conductive network. Furthermore, the redox properties and sodium storage average potential platform of C4Q are first calculated by density functional theory (DFT).

Imaging techniques of upper tract urothelial carcinoma (UTUC) are presently limited. Upconversion particles (UCPs) could be used to target tumors for imaging. The present study aimed to assess the value of a nano-UCP as a diagnostic probe for deep tumor tissue, including UTUC. Polymer-coated water-soluble UCPs were synthesized. The pH Low Insertion Peptide (pHLIP) polypeptide was synthesized using the solid phase method. The silane shell surface was modified to present amino or carboxyl groups. Succinimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate was used for the coupling of the polypeptide to the UCPs. An animal model of subcutaneous tumor was established in 4-week old nude mice using UTUC cells. Urinary tract epithelial cancer T24 cells were injected into the diaphragm below the heart. PHLIP-UCP solution (1 ml) was injected into the abdominal cavity of each animal. Optical detection was performed using a small animal living body multispectral imaging system. UCPs dispersed in chloroform emitted no light under natural light, while they emitted a green light when excited with a 980-nm laser. The maximum emission wavelength of Ho3+-doped UCPs was ~550 nm and the red emission region was ~650 nm. As the coated UCPs possessed a tendency to agglomerate and precipitate, the yield of the UCPs in the aqueous phase was reduced. Tumors could be successfully imaged in tumor-bearing mice. NaYF4: Yb, Ho3+ UPCs could be used for the detection of UTUC, thus further studies are required to determine if it could be used in larger animals with deeper tumors.

An amphiphilic block copolymer poly(ethylene oxide)-b-poly(butylene oxide) (PEO-PBO) was evaluated as a carrier for therapeutic delivery of paclitaxel (PTX). PEO-PBO and PTX form nanoparticles (NPs) by self-assembly upon hydration. The size of these NPs was about 92.71nm and the zeta potential was -5.06mV, which met the requirements for passive tumor targeting through the enhanced permeability and retention effect. Compared with a commonly used block copolymer poly(ethylene glycol)-b-poly-D,L-(lactic acid) (PEG-PDLLA), PEO-PBO forms nanoparticles with superior pharmacokinetic, biodistribution, and tumor inhibitory properties. Meanwhile, results of hemolysis study and CMC determination showed that PEO-PBO had better biocompatibility and stability than PEG-PDLLA. These data suggest that PEO-PBO has potential for application in drug delivery and warrant further evaluation.

Halomonas alkalicola CICC 11012s is an alkaliphilic and halotolerant bacterium isolated from a soap-making tank (pH > 10) from a household-product plant. This strain can propagate at pH 12.5, which is fatal to most bacteria. Genomic analysis revealed that the genome size was 3,511,738 bp and contained 3295 protein-coding genes, including a complete cell wall and plasma membrane lipid biosynthesis pathway. Furthermore, four putative Na+/H+ and K+/H+ antiporter genes, or gene clusters, designated as HaNhaD, HaNhaP, HaMrp and HaPha, were identified within the genome. Heterologous expression of these genes in antiporter-deficient Escherichia coli indicated that HaNhaD, an Na+/H+ antiporter, played a dominant role in Na+ tolerance and pH homeostasis in acidic, neutral and alkaline environments. In addition, HaMrp exhibited Na+ tolerance; however, it functioned mainly in alkaline conditions. Both HaNhaP and HaPha were identified as K+/H+ antiporters that played an important role in high alkalinity and salinity. In summary, genome analysis and heterologous expression experiments demonstrated that a complete set of adaptive strategies have been developed by the double extremophilic strain CICC 11012s in response to alkalinity and salinity. Specifically, four antiporters exhibiting different physiological roles for different situations worked together to support the strain in harsh surroundings.

A Gram-stain-negative, rod-shaped, bright-yellow-pigmented bacterium, designated 164T, was isolated from a used sponge for equipment cleaning at a household product plant in China. The 16S rRNA gene sequence comparisons indicated that strain 164T was most closely related to Novosphingobium panipatense DSM 22890T (98.28 % similarity) and shared sequence similarities of 97.73–98.27 % with other members of the genus Novosphingobium . In DNA–DNA hybridization studies the relatedness between strain 164T and its closest phylogenetic neighbours was

This paper aimed to compare the mode of action of a stannous fluoride-containing toothpaste with a conventional sodium fluoride-containing toothpaste on anti-biofilm properties.A three-species biofilm model that consists of Streptococcus mutans, Streptococcus sanguinis and Porphyromonas gingivalis was established to compare the anti-biofilm properties of a stannous fluoride-containing toothpaste (CPH), a conventional sodium fluoride-containing toothpaste (CCP) and a negative control (PBS). The 48h biofilms were subjected to two-minute episodes of treatment with test agents twice a day for 5 consecutive days. Crystal violet staining and XTT assays were used to evaluate the biomass and viability of the treated biofilm. Live/dead staining and bacteria/extracellular polysaccharides (EPS) double-staining were used to visualize the biofilm structure and to quantify microbial/extracellular components of the treated biofilms. Species-specific fluorescent in situ hybridization and quantitative polymerase chain reaction (qPCR) were used to analyze microbial composition of the biofilms after treatment.The biomass and viability of the biofilms were significantly reduced after CPH toothpaste treatment. The inhibitory effect was further confirmed by the live/dead staining. The EPS amounts of the three-species biofilm were significantly reduced by CCP and CPH treatments, and CPH toothpaste demonstrated significant inhibition on EPS production. More importantly, CPH toothpaste significantly suppressed S. mutans and P. gingvalis, and enriched S. sanguinis in the three-species biofilm. In all experiments CPH had a significantly greater effect than CCP (p0.05) and CCP had a greater effect than PBS (p0.05).Stannous fluoride-containing toothpaste not only showed better inhibitory effect against oral microbial biofilm, but was also able to modulate microbial composition within multi-species biofilm compared with conventional sodium fluoride-containing toothpaste.

BACKGROUND Qishen Yiqi Dropping Pills (QYDP) is a Chinese traditional medicine that has been applied to treat coronary heart disease and ischemic heart failure in China. However, few studies have explored whether QYDP exerted an effect on doxorubicin (Doxo)-induced cardiotoxicity. Hence, in this study we investigated the effect of QYDP on cardiotoxicity induced by doxorubicin (Doxo) and its potential mechanism. MATERIAL AND METHODS Male C57BL/6 mice (20-25 g, 8-10 weeks old) were randomly assigned to 4 groups: Control group, QYDP group, Doxo group, and QYDP+Doxo group. The mice were intraperitoneal injected with Doxo weekly for 4 weeks to mimic the chronic toxicity. Four weeks after Doxo injection, echocardiography was applied to evaluate the left ventricular (LV) function, and the structure of the cardiac muscle fibers was analyzed with anti-actinin-2 antibody staining by immunofluorescence. Moreover, TUNEL staining and western blot analysis of Bax protein, Bcl-2 protein, and cleaved caspase-3 protein expression levels were conducted to explore whether QYDP exerted effect on cardiac apoptosis. In addition, Masson trichrome staining and western blot analysis of alpha-SMA protein expression levels were used to evaluate whether QYDP exerted an effect on cardiac fibrosis. Western blots and quantitative real-time polymerase chain reaction were applied to detect the vascular endothelial growth factor (VEGF) protein and mRNA levels in the myocardial tissue, and anti-CD31 antibody staining by immunohistochemistry was employed to explore whether QYDP exerted an effect on cardiac angiogenesis. RESULTS QYDP effectively attenuated cardiac dysfunction and cardiac muscle fibers disruption in Doxo treated mice. Moreover, QYDP reduced myocardial apoptosis and myocardial fibrosis in Doxo treated mice, accompanied with elevated protein levels of VEGF and enhancement of myocardial microvessel density. CONCLUSIONS QYDP could protect against Doxo-induced cardiotoxicity, which may be closely associated with enhanced cardiac angiogenesis. Hence, QYDP could be a promising alternative for the treatment of Doxo-induced cardiotoxicity.

Background/Aims: Cancer stem cells (CSCs) are largely responsible for tumor relapse and metastatic behavior. Doublecortin-like kinase 1 (DCLK1) was recently reported to be a biomarker for gastrointestinal CSCs and involved in the epithelial-mesenchymal transition (EMT) and tumor progression. B cell-specific Moloney murine leukemia virus insertion site 1 (Bmi-1) is a crucial regulator of CSC self-renewal, malignant transformation and EMT, and a previous study from our group showed that Bmi-1 is upregulated in pancreatic cancer progression and participates in EMT. However, it remains unclear whether DCLK1 is involved in pancreatic cancer or whether DCLK1 is associated with the altered level of Bmi-1 expression. Methods: The correlation of DCLK1 expression and clinical features of pancreatic cancer was analyzed in 210 paraffin-embedded archived pancreatic cancer specimens by immunohistochemical analysis. The biological effects of DCLK1 siRNA on cells were investigated by examining cell proliferation using a cell counting kit and cell colony assays, cell migration by wound healing assay and cell invasion by Transwell invasion assay. We further investigated the effect of therapeutic siRNA targeting DCLK1 on pancreatic cancer cell growth in vivo. Moreover, the molecular mechanism by which DCLK1 upregulates Bmi-1 expression was explored using real-time PCR, western blotting and Co-immunoprecipitation assay. Results: DCLK1 is overexpressed in pancreatic cancer and is related to metastasis and prognosis. Knockdown of DCLK1 markedly suppressed cell growth in vitro and in vivo and also inhibited the migration and invasion of pancreatic cancer cells. Furthermore, we found that DCLK1 silencing could inhibit EMT in cancer cells via downregulation of Bmi-1 and the mesenchymal markers Snail and Vimentin and upregulation of the epithelial marker E-cadherin. Moreover, high DCLK1 expression in human pancreatic cancer samples was associated with a mesenchymal phenotype and increased cell proliferation. Further co-immunoprecipitation indicated that DCLK1 did not interact with Bmi-1 directly. Conclusion: Our data suggest that upregulation of DCLK1 may contribute to pancreatic cancer metastasis and poor prognosis by increasing Bmi-1 expression indirectly. The findings indicate that inhibiting DCLK1 expression might be a novel strategy for pancreatic cancer therapy.

Circular RNAs (CircRNAs) are a novel type of endogenous noncoding RNAs that regulate target gene expression by interacting with microRNA (miRNA). Emerging evidence shows that dysregulation of circRNAs plays important roles in biological and pathological processes, including cancer development and progression. The functional role of circRNA in PDAC (pancreatic ductal adenocarcinoma) remains to be investigated. In this study, high throughput microarray assay revealed that hsa_circ_0000977 was aberrantly up-regulated in pancreatic cancer tissues; this was also validated by qRT-PCR. Silencing hsa_circ_0000977 suppressed pancreatic cancer cell proliferation and induced cell cycle arrest, which was simulated by hsa-miR-874-3p mimics and blocked by hsa-miR-874-3p inhibitor. Bioinformatics analysis predicted that there is an hsa_circ_0000977/hsa-miR-874-3p/PLK1 (Polo like kinase 1) axis in pancreatic cancer progression. Dual-luciferase reporter system and FISH assay validated the direct interaction of hsa_circ_0000977, hsa-miR-874-3p, and PLK1. Western blot verified that inhibition of hsa_circ_0000977 decreased PLK1 expression. Furthermore, silencing hsa_circ_0000977 suppressed pancreatic cancer growth in vivo. Altogether, silencing hsa_circ_0000977 suppresses progression of pancreatic cancer by interacting with hsa-miR-874-3p and decreasing inhibiting PLK1 expression. Our results may provide a promising strategy for future diagnosis and treatment of pancreatic cancer.

Fluorescence imaging is a broadly interesting and rapidly growing strategy for non-invasive clinical applications. However, because of interference from light scattering, absorbance, and tissue autofluorescence, the images can exhibit low sensitivity and poor quality. Upconversion fluorescence imaging, which is based on the use of near-infrared (NIR) light for excitation, has recently been introduced as an improved approach to minimize the effects of light scattering and tissue autofluorescence. This strategy is promising for ultrasensitive and deep tissue imaging applications. However, the emitted upconversion fluorescence signals are primarily in the visible range and are likely to be absorbed and scattered by tissues. Therefore, different anatomic structures could impose various effects on the quality of the images. In this study, we used upconversion-core/silica-shell nanoprobes to evaluate the quality of upconversion fluorescence at different anatomic locations in athymic nude mice. The nanoprobe contained an upconversion core, which was green (β-NaYF4:Yb3+/Ho3+) or red (β-NaYF4:Yb3+/Er3+), and a nonporous silica shell to allow for multicolor imaging. High-quality upconversion fluorescence signals were detected with signal-to-noise ratios of up to 170 at tissue depths of up to - 1.0 cm when a 980 nm laser excitation source and a bandpass emission filter were used. The presence of dense tissue structures along the imaging path reduced the signal intensity and imaging quality, and nanoprobes with longer-wavelength emission spectra were therefore preferable. This study offers a detailed analysis of the quality of upconversion signals in vivo inside different anatomic structures. Such information could be essential for the analysis of upconversion fluorescence images in any in vivo biodiagnostic and microbial tracking applications.

The ubiquitous Acinetobacter baumannii is an important and troublesome pathogen of nosocomial infection. Multidrug-resistant A baumannii meningitis is very difficult to treat, usually with high mortality. The disease is generally associated with craniotomy, but rarely with lumbar puncture. However, in our case, a 45-year-old male construction worker suffered multidrug-resistant A baumannii meningitis associated with lumbar puncture. The patient responded poorly to the initial treatment with an intravenous infusion of tigecycline. However, later treatment with an intrathecal injection of tigecycline (concentration 1 mg/mL) at a dose of 10 mg every 12 hours proved to be highly efficacious. Thus, intrathecal injection of tigecycline should be seriously considered as a treatment for multidrug-resistant A baumannii meningitis.

The therapeutic index for chemotherapeutic drugs is determined in part by systemic toxicity, so strategies for dose intensification to improve efficacy must also address tolerability. In addressing this issue, we have investigated a novel combinatorial strategy of reconstructing a drug molecule and using sequential drug-induced nanoassembly to fabricate supramolecular nanomedicines (SNM). Using cabazitaxel as a target agent, we established that individual synthetic prodrugs tethered with polyunsaturated fatty acids were capable of recapitulating self-assembly behavior independent of exogenous excipients. The resulting SNM could be further refined by PEGylation with amphiphilic copolymers suitable for preclinical studies. Among these cabazitaxel derivatives, docosahexaenoic acid–derived compound 1 retained high antiproliferative activity. SNM assembled with compound 1 displayed an unexpected enhancement of tolerability in animals along with effective therapeutic efficacy in a mouse xenograft model of human cancer, compared with free drug administered in its clinical formulation. Overall, our studies showed how attaching flexible lipid chains to a hydrophobic and highly toxic anticancer drug can convert it to a systemic self-deliverable nanotherapy, preserving its pharmacologic efficacy while improving its safety profile. Cancer Res; 77(24); 6963–74. ©2017 AACR.

In this work, we demonstrate a new kind of Pt-free counter electrode for dye-sensitized solar cells (DSCs). Polypyrrole-cobalt-carbon (PPY-Co-C) nanocomposites, with the advantages of low cost and simple preparation, show favorable catalytic activity in promoting tri-iodide reduction. The DSC composed of the PPY-Co-C nanocomposite electrode exhibits an acceptable energy conversion efficiency of 6.01%, a considerable short-circuit photocurrent of 15.33 mA cm−2, and a low charge-transfer resistance of 1.5 Ω cm2. The overall performance of PPY-Co-C is superior to the carbon counterparts and comparable with the platinum reference, rendering them efficient and promising counter electrode materials for DSCs.

Developing organic compounds with multifunctional groups to be used as electrode materials for rechargeable sodium-ion batteries is very important. The organic tetrasodium salt of 2,5-dihydroxyterephthalic acid (Na(4)DHTPA; Na4C8H2O6), which was prepared through a green one-pot method, was investigated at potential windows of 1.6-2.8 V as the positive electrode or 0.1-1.8 Vas the negative electrode (vs. Na+/Na), each delivering compatible and stable capacities of ca. 180 mAhg(-1) with excellent cycling. A combination of electrochemical, spectroscopic and computational studies revealed that reversible uptake/removal of two Na+ ions is associated with the enolate groups at 1.6-2.8 V (Na2C8H2O6/Na4C8H2O6) and the carboxylate groups at 0.1-1.8 V (Na4C8H2O6/Na6C8H2O6). The use of Na4C8H2O6 as the initial active materials for both electrodes provided the first example of all-organic rocking-chair SIBs with an average operation voltage of 1.8 V and a practical energy density of about 65 Whkg(-1).

We report the preparation of porous CuO nanowires that are composed of nanoparticles (∼50 nm) via a simple decomposition of a Cu(OH)2 precursor and their application as the anode materials of rechargeable Na-ion batteries. The as-prepared porous CuO nanowires exhibit a Brunauer-Emmett-Teller (BET) surface area of 13.05 m2·g−1, which is six times larger than that of bulk CuO (2.16 m2·g−1). The anode of porous CuO nanowires showed discharge capacities of 640 mA·h·g−1 in the first cycle and 303 mA·h·g−1 after 50 cycles at 50 mA·g−1. The high capacity is attributed to porous nanostructure which facilitates fast Na-intercalation kinetics. The mechanism of electrochemical Na-storage based on conversion reactions has been studied through cyclic voltammetry, X-ray diffraction (XRD), Raman spectroscopy, and high resolution transmission electron microscopy (HRTEM). It is demonstrated that in the discharge process, Na+ ions first insert into CuO to form a Cu1−xIICuxIO1−x/2 solid and a Na2O matrix then Cu1−xIICuxIO1−x/2 reacts with Na+ to produce Cu2O, and finally Cu2O decompose into Cu nanoparticles enclosed in a Na2O matrix. During the charge process, Cu nanoparticles are first oxidized to generate Cu2O and then converted back to CuO. This result contributes to the design and mechanistic analysis of high-performance anodes for rechargeable Na-ion batteries.

Organic tetralithium salts of 2,5-dihydroxyterephthalic acid (Li4C8H2O6) with the morphologies of bulk, nanoparticles, and nanosheets have been investigated as the active materials of either positive or negative electrode of rechargeable lithium-ion batteries. It is demonstrated that, in the electrolyte of LiPF6 dissolved in ethylene carbonate (EC) and dimethyl carbonate (DMC), reversible two-Li-ion electrochemical reactions are taking place with redox Li4C8H2O6/Li2C8H2O6 at ~2.6 V for a positive electrode and Li4C8H2O6/Li6C8H2O6 at ~0.8 V for a negative electrode, respectively. In the observed system, the electrochemical performance of high to low order is nanosheetsnanoparticlesbulk. Remarkably, Li4C8H2O6 nanosheets show the discharge capacities of 223 and 145 mAh g(-1) at 0.1 and 5 C rates, respectively. A capacity retention of 95% is sustained after 50 cycles at 0.1 C rate charge/discharge and room temperature. Moreover, charging the symmetrical cells with Li4C8H2O6 nanosheets as the initial active materials of both positive and negative electrodes produces all-organic LIBs with an average operation voltage of 1.8 V and an energy density of about 130 Wh kg(-1), enlightening the design and application of organic Li-reservoir compounds with nanostructures for all organic LIBs.

Lithium-sulfur batteries have attracted a great interest in electrochemical energy conversion and storage, but their discharge mechanism remains not well understood up to now. Here, we report density functional theory (DFT) calculation study of the discharge mechanism for lithium-sulfur batteries which are based on the structure of S8 and Li2Sx (1≤x≤8) clusters. The results show that for Li2Sx (1≤x≤8) clusters, the most stable geometry is chainlike when x=1 and 6, while the minimal-energy structure is found to be cyclic when x = 2–5, 7, 8. The stability of Li2Sx (1≤x≤8) clusters increases with the decreasing x value, indicating a favorable thermodynamic tendency of transition from S8 to Li2S. A three-step reaction route has been proposed during the discharge process, that is, S8→Li2S4 at about 2.30 V, Li2S4→Li2S2 at around 2.22 V, and Li2S2→Li2S at 2.18 V. Furthermore, the effect of the electrolyte on the potential platform has been also investigated. The discharge potential is found to increase with the decrease of dielectric constant of the electrolyte. The computational results could provide insights into further understanding the discharge mechanism of lithium-sulfur batteries.

A Gram-stain-negative, alkaliphilic and moderately halophilic bacterium, designated 56-L4-10aEnT, was isolated from a household product plant in China. Cells of the novel isolate were rod-shaped, non-spore-forming and non-motile. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain 56-L4-10aEnT belongs to the genus Halomonas , with the six closest neighbours being Halomonas mongoliensis Z-7009T (97.59 % 16S rRNA gene sequence similarity), Halomonas ventosae Al12T (97.35 %), Halomonas campaniensis 5AGT (97.22 %), Halomonas alimentaria YKJ-16T (97.22 %), Halomonas shengliensis SL014B-85T (97.12 %) and Halomonas fontilapidosi 5CRT (97.09 %). The main polar lipids of strain 56-L4-10aEnT contained diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The predominant respiratory quinone was Q-9, with Q-8 as a minor component. The major fatty acids were C18 : 1ω7c/C18 : 1ω6c and C16 : 0. Strain 56-L4-10aEnT was clearly distinguished from the type strains mentioned above through phylogenetic analysis, DNA–DNA hybridization, fatty acid composition data and a range of physiological and biochemical characteristics comparisons. It is evident from the genotypic and phenotypic data that strain 56-L4-10aEnTcould be classified as a representative of a novel species of the genus Halomonas , for which the name Halomonas alkalicola sp. nov. is proposed. The type strain is 56-L4-10aEnT (=CICC 11012sT=DSM 103354T).

A novel biosensor based on single-stranded DNA (ssDNA) probe functionalized aluminum anodized oxide (AAO) nanopore membranes was demonstrated for Escherichia coli O157:H7 DNA detection. An original and dynamic polymerase-extending (PE) DNA hybridization procedure is proposed, where hybridization happens in the existence of Taq DNA polymerase and dNTPs under controlled reaction temperature. The probe strand would be extended as long as the target DNA strand, then the capability to block the ionic flow in the pores has been prominently enhanced by the double strand complex. We have investigated the variation of ionic conductivity during the fabrication of the film and the hybridization using cyclic voltammetry and impedance spectroscopy. The present approach provides low detection limit for DNA (a few hundreds of pmol), rapid label-free and easy-to-use bacteria detection, which holds the potential for future use in various ss-DNA analyses by integrated into a self-contained biochip.

This paper presents development of a quartz crystal microbalance (QCM) biosensor for real-time detection of E. coli O157:H7 DNA based on nanogold particles amplification. Many inner Au nanoparticles were immobilized onto the thioled surface of the Au electrode, then more specific thiolated single-stranded DNA (ssDNA) probes could be fixed through Au-SH bonding. The hybridization was induced by exposing the ssDNA probe to the complementary target DNA of E. coli O157:H7 gene eaeA, then resulted in a mass change and corresponding frequency shifts (Δf) of the QCM. The outer avidin-coated Au nanoparticles could combine with the target DNA to increase the mass. The electrochemical techniques, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were adopted to manifest and character each step. The target DNA corresponding to 2.0×103 colony forming unit (CFU)/mL E. coli O157:H7 cells can be detected by this biosensor, so it is practical to develop a sensitive and effective QCM biosensor for pathogenic bacteria detection based on specific DNA analysis. The piezoelectric biosensing system has potential for further applications, such as food safety and environment monitoring, and this approach lays the groundwork for incorporating the method into an integrated system for in-field bacteria detection.

Fluorescence imaging is a broadly interesting and rapidly growing strategy for non-invasive clinical applications. However, because of interference from light scattering, absorbance, and tissue autofluorescence, the images can exhibit low sensitivity and poor quality. Upconversion fluorescence imaging, which is based on the use of near-infrared (NIR) light for excitation, has recently been introduced as an improved approach to minimize the effects of light scattering and tissue autofluorescence. This strategy is promising for ultrasensitive and deep tissue imaging applications. However, the emitted upconversion fluorescence signals are primarily in the visible range and are likely to be absorbed and scattered by tissues. Therefore, different anatomic structures could impose various effects on the quality of the images. In this study, we used upconversion-core/silica-shell nanoprobes to evaluate the quality of upconversion fluorescence at different anatomic locations in athymic nude mice. The nanoprobe contained an upconversion core, which was green (β-NaYF4:Yb3+/Ho3+) or red (β-NaYF4:Yb3+/Er3+), and a nonporous silica shell to allow for multicolor imaging. High-quality upconversion fluorescence signals were detected with signal-to-noise ratios of up to 170 at tissue depths of up to - 1.0 cm when a 980 nm laser excitation source and a bandpass emission filter were used. The presence of dense tissue structures along the imaging path reduced the signal intensity and imaging quality, and nanoprobes with longer-wavelength emission spectra were therefore preferable. This study offers a detailed analysis of the quality of upconversion signals in vivo inside different anatomic structures. Such information could be essential for the analysis of upconversion fluorescence images in any in vivo biodiagnostic and microbial tracking applications.

It is widely recognized that the chipless finishing process–the burnishing process can be used efficaciously to reduce the surface roughness and increase the surface hardness of a workpiece. But most of previous works published on the burnishing process concentrated on experimental researches in the last few years. The mechanism of the burnishing process which is very important for spreading the burnishing process has been explored based on contact mechanics. The simulation curve is obtained from a theoretical model. Theoretical results are compared with the experiments in which aluminum alloy LY12 was selected as material for making the specimens and a new cylindrical polycrystalline diamond tool developed by us was used for the burnishing process. The comparison shows that the theoretical model is basically correct in describing the burnishing process.

This paper presents a three-dimensional burnishing force model which was studied based on elastic-plastic contact mechanics and elastic-plastic impact mechanics. Effects from different aspects are involved in this model, such as macro- and micro-shape parameters, mechanical properties, physics properties, and burnishing process parameters. From this burnishing force model, a more ideal burnished surface can be obtained by deliberately controlling certain parameters. So it can be said that the burnishing force model obtained is very important for promoting the use of the burnishing process, which can be used effectively to reduce surface roughness and increase surface hardness of a workpiece. A simulation curve is obtained from the model. Burnishing process experiments have been undertaken in which yellow brass H62 was selected as the specimen material and a new cylindrical polycrystalline diamond tool developed by the authors was employed in the burnishing process. The majority of the simulation curves are in good agreement with the experimental curves. It has been found from both theoretical and practical studies that three components of burnishing force increase exponentially with the increase of burnishing depth and the Y dimensional burnishing force is much larger than the other two; this phenomenon is very different from that of the cutting process.

The approximate cutting force models in three-dimensional separating type ultrasonic elliptical vibration cutting are proposed in present paper. The theoretical models of the stresses of deformation zone on the workpiece edge in burr formation in ultrasonic elliptical vibration cutting are derived based on three-dimensional cutting model, and the reason for the burr being suppressed by applying ultrasonic elliptical vibration is clarified theoretically. Finally, the effect of ultrasonic elliptical vibration cutting on the burr is verified experimentally.

According to the results obtained from the boundary condition study of the burnishing process, cylindrical polycrystalline diamond (PCD) tools have been designed and fabricated. We probe deeper in the burnishing process by comparing the mechanics of using cylindrical PCD tools to work on aluminium alloy and brass compared to turning. The empirical equations of three components of the burnishing force were established with the aid of a quartz force measuring system and statistical methods. The results obtained show that the distributions of force are different between burnishing and turning. Furthermore, the effect of the burnishing parameters on the burnishing force and the surface microhardness of the workpiece were examined with theoretical analysis. Here, it was concluded that the burnishing feed and depth are the most significant factors affecting the burnishing force and surface microhardness.