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comparative toxicity of a food additive TiO2, a bulk TiO2, and a nano-sized P25 to a model organism the nematode c-elegans

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ENVIRONMENTAL ScIENcE AND POLLUTION RESEARcH 2019年第4期26卷 3556-3568页

作者： Ma, Hongbo Lenz, Kade A. Gao, Xianfeng Li, Shibin Wallis, Lindsay K. Univ Wisconsin Joseph J Zilber Sch Publ Hlth Milwaukee WI 53201 USA Univ Wisconsin Dept Mat Sci & Engn Milwaukee WI 53201 USA US EPA Midcontinent Ecol Div Duluth MN USA

To help fill the knowledge gap regarding the potential human health impacts of food pigment TiO2, a comparative toxicity study was performed on a food-grade TiO2 (f-TiO2), a bulk TiO2 (b-TiO2), and a nano-sized TiO2 (Degussa P25), and in the nematode caenorhabditis elegans. Acute phototoxicity and chronic toxicity effects including reproduction, lifespan, and vulval integrity were evaluated. The f-TiO2, b-TiO2, and P25 had a primary particle size (size range) of 149 (53-308) nm, 129 (64-259) nm, and 26 (11-52) nm, respectively. P25 showed the greatest phototoxicity with a 24-h Lc50 of 6.0mg/L (95% cI 5.95, 6.3), followed by the f-TiO2 (Lc50=6.55mg/L (95% cI 6.35, 6.75)), and b-TiO2 was the least toxic. All three TiO2 (1-10mg/L) induced concentration-dependent effects on the worm's reproduction, with a reduction in brood size by 8.5 to 34%. They all caused a reduction of worm lifespan, accompanied by an increased frequency of age-associated vulval integrity defects (Avid). The impact on lifespan and Avid phenotype was more notable for P25 than the f-TiO2 or b-TiO2. Ingestion and accumulation of TiO2 particles in the worm intestine was observed for all three materials by light microscopy. These findings demonstrate that the food pigment TiO2 induces toxicity effects in the worm and further studies are needed to elucidate the human health implication of such toxicities.

关键词： Food additive TiO2 Toxicity c elegans Vulval integrity

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Preparation of LiFePO4/c via high-temperature ball-milling route and Box-Behnken design-based optimization

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IONIcS 2019年第10期25卷 4597-4606页

作者： Li, Xuetian cui, Yonghui Yu, Lina Shao, Hongmei Shao, Zhongcai Li, chuang Shao, Zhongbao Shenyang Ligong Univ Sch Environm & Chem Engn Shenyang 110159 Liaoning Peoples R China Shenyang Ligong Univ Sch Mat Sci & Engn Shenyang 110159 Liaoning Peoples R China Northeastern Univ Sch Met Shenyang 110819 Liaoning Peoples R China

LiFePO4/c cathode material was prepared via high-temperature ball-milling route with ultrasonic dispersion as mixing process using eutectic molten salt (0.76 LiOH center dot H2O-0.24 Li2cO3) as lithium source. Box-Behnken design was used to study the combined effects of ultrasonic time, ball-milling temperature, and ball-milling time on the discharge capacity to obtain the optimum predicted conditions. The optimum conditions were as follows: ultrasonic time was 63 min, ball-milling temperature was 638 degrees c, and ball-milling time was 7 h. LiFePO4/c prepared from the optimized experimental conditions exhibited a well electrochemical performance;its discharge capacity was 161.3 mAh g(-1) at a 0.1 c-rate which was in consistence with the predicted discharge capacity of 160.2 mAh g(-1). Moreover, its capacity retention rate achieved 93.6% at a 10 c-rate over 100 cycles.

关键词： LiFePO4 c cathode material High-temperature ball-milling route Box-Behnken design

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Seismic retrofitting of gravity-loads designed r.c. framed buildings combining cFRP and hysteretic damped braces

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BULLETIN OF EARTHQUAKE ENGINEERING 2019年第6期17卷 3423-3445页

作者： Mazza, Fabio Mazza, Mirko Univ Calabria Dipartimento Ingn Civile I-87036 Cosenza Italy

Despite the effectiveness of carbon fibre reinforced polymers (cFRPs) and steel braces equipped with hysteretic dissipative devices (HYDBs) to improve the seismic performance of r.c. framed structures, the only use of cFRPs may be unsatisfactory for the retrofitting of buildings designed for gravity loads only while HDYBs may be unsuitable without a preliminary upgrading. The use of cFRP and HYDB as a combined technique for the seismic retrofitting of reinforced concrete (r.c.) buildings is investigated herein. To this end, two-, four- and eight-storey r.c. framed structures are designed with reference to the structural codes for r.c. buildings in force in Italy before and after 1971. A computer code for the nonlinear static and dynamic analysis of r.c. framed structures is modified to include cFRPs and HYDBs. Firstly, the nonlinear static analysis of the original test structures is carried with the aim of improving preliminarily strength and displacement capacities by applying cFRPs laminates, at the top and bottom sides of r.c. frame members, and cFRPs wraps, at the critical end zones of columns, respectively. Then, a displacement-based design procedure of HYDBs is adopted to complete the seismic retrofitting, starting from capacity curves of the upgraded test structures. To check the reliability of the combined cFRP-HYDB technique, nonlinear dynamic analysis of the original and retrofitted structures is performed considering two sets of seven near- and far-fault ground motions scaled to the seismic design level. Results highlight that the insertion of the HYDBs is effective in reducing the seismic demand of previously upgraded cFRP structures, with Post71 types generally performing better than Ante71 ones.

关键词： R c framed structures carbon fibre reinforced polymers Hysteretic damped braces Seismic upgrading Seismic retrofitting

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Role of serum cystatin c in the prediction of contrast-induced nephropathy after intra-arterial interventions

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chinese Medical Journal 2020年第4期133卷 408-414页

作者： Zheng-Yu Wang Yong-Li Wang Jian Wei Long Jin Zhen-chang Wang Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Interventional Radiology The Sixth People's Hospital South CampusShanghai Jiao Tong UniversityShanghai 201499China

Background:The diagnosis of contrast-induced nephropathy(cIN)is usually based on changes in serum creatinine(scr).However,scr has poor sensitivity as a biomarker of kidney *** aim of this study was to investigate the usefulness of serum cystatin c(scysc)to predict cIN after intra-arterial ***:A total of 360 consecutive patients underwent intra-arterial procedures using digital subtraction ***,scysc,and estimated glomerular filtration rate were measured at 1 to 2 days before and at 48,72 h,and 7 days after the ***:Thirty-one patients(8.61%)developed *** operating characteristic(ROc)curve analysis showed that preoperative scysc levels had good discriminatory power(area under the curve[AUc]=0.634;95%confidence interval[cI]=0.526-0.743)for evaluating the risk of cIN after an endovascular procedure,with a sensitivity of 53.33%and specificity of 73.70%.ROc analysis showed that scysc at 48 h after contrast medium administration was predictive of cIN after an endovascular procedure(AUc=0.735;95%cI=0.647-0.822)with satisfactory sensitivity of 74.20%and specificity of 63.90%.Diabetes mellitus was an independent risk factor for cIN(odds ratio=2.778;95%cI=1.045-7.382;P=0.040).conclusions:Scysc is an appropriate biomarker to predict the occurrence of *** scysc before an intervention is useful to obtain a preliminary estimate of the risk of cIN.A 48-h cut-off value of scysc of 0.99 mg/L after an endovascular procedure may help to rule out patients at lower risk of cIN.

关键词： contrast-induced nephropathy Intra-arterial intervention Serum cystatin c Serum creatinine

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High electrochemical performance of Li4Ti5O12/c synthesized by ball milling and direct flaming of acetylene gas as anode for lithium-ion battery

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IONIcS 2019年第11期25卷 5315-5322页

作者： Noerochim, Lukman Maghfiroh, Amalia Ma'rifatul Widyastuti Susanti, Diah Priyono, Slamet Prihandoko, Bambang Sepuluh Nopember Inst Technol Dept Mat & Met Engn Surabaya 60111 Indonesia Indonesian Inst Sci Res Ctr Phys Serpong Indonesia

Li4Ti5O12/c has been successfully synthesized by a solid-state reaction method of Li2cO3 and TiO2 followed by direct flaming of acetylene gas. Li4Ti5O12 with 2-h milling time is indexed as single-phase crystal structure of Li4Ti5O12 (JcPDS 04-0477). The SEM results show particle sizes between 0.192 and 0.360 mu m with a spherical shape, but there is agglomeration due to high temperature when the direct flaming of acetylene gas process is applied. The desired carbon content by direct flaming of acetylene gas is still very low at 0.6% for 10 min and 0.9% for 20 min. Li4Ti5O12 with 10 min of direct flaming of acetylene gas has the highest specific discharge capacity of 210.61 mAh/g. This is attributed to the pure single phase and the higher conductivity of the sample. This result shows that Li4Ti5O12/c synthesized by ball milling and direct flaming of acetylene gas could be a good candidate as anode for lithium-ion battery.

关键词： Li4Ti5O12 c Ball milling Direct flaming Anode Lithium-ion battery

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c/c++中指针编程的破解

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计算机时代 2022年第11期 121-124,129页

作者：苏杭丽李燕童端南京财经大学信息工程学院江苏南京210023

针对c/c++指针编程难的问题,提出“三步法”的解决方法。“三步法”将指针编程的整个过程归纳为固定步骤和具体任务,破解指针的抽象。在完成“三步法”的具体任务时,针对指向基本变量、一维数组、二维数组的指针,分别给出指针的定义、... 详细信息

针对c/c++指针编程难的问题,提出“三步法”的解决方法。“三步法”将指针编程的整个过程归纳为固定步骤和具体任务,破解指针的抽象。在完成“三步法”的具体任务时,针对指向基本变量、一维数组、二维数组的指针,分别给出指针的定义、初始值、表示任一元素的地址和值的固定格式,并从外形符号找出相对应的“等价”,破解指针的灵活性。最后举例说明“三步法”的使用。“三步法”在教学中取得了很好的效果。

关键词： c c++ 指针三步法

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Acinetobacter sp. mediated synthesis of AgNPs, its optimization, characterization and synergistic antifungal activity against c. albicans

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JOURNAL OF APPLIED MIcROBIOLOGY 2019年第2期127卷 445-458页

作者： Nadhe, S. B. Singh, R. Wadhwani, S. A. chopade, B. A. Savitribai Phule Pune Univ Dept Microbiol Pune Maharashtra India SIES Coll Arts Sci & Commerce Dept Biotechnol Mumbai Maharashtra India Dr Babasaheb Ambedkar Marathwada Univ Aurangabad 431004 Maharashtra India

Aims To synthesize silver nanoparticles (AgNPs) with cell free extract of Acinetobacter sp. and evaluate antifungal activity against planktonic and biofilm of candida. Also, to study mechanism of antifungal action of AgNPs. Methods and Result Acinetobacter spp were screened for synthesis of AgNPs. Physio-chemical parameters were optimized to obtained monodispersed nanoparticles. Optimized nanoparticles were characterized using spectroscopic, microscopic and diffraction techniques. Antifungal and biofilm disruption activity of AgNPs (10 +/- 5 nm) were investigated against c. albicans. Mechanism of antifungal activity of nanosilver was deduced by growth curve, reactive oxygen species generation, thiol interaction and microscopic analysis. Acinetobacter sp. GWRFH 45 gave maximum synthesis of AgNPs. At optimized condition monodispersed, spherical nanoparticles were obtained which were crystalline with negative surface charge. AgNPs exhibited antifungal activity against planktonic cells and biofilm of candida. AgNPs showed synergistic effect with amphotericin B as well as fluconazole against biofilm disruption. AgNPs were found to affect growth of candida, generate reactive oxygen species and disrupt cellular morphology. conclusions cell free extract of A. calcoaceticus GWRFH 45 has ability to synthesize AgNPs. AgNPs alone and in combination with drugs have potential to inhibit c. albicans. Significance and Impact of the Study This is the first report of bacteriogenic AgNPs used in combination with antifungal drugs against candida.

关键词： Acinetobacter sp AgNPs antifungal biofilm c albicans disrupt morphology reactive oxygen species

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Histone demethylase KDM5A is transactivated by the transcription factor c/EBP and promotes preadipocyte differentiation by inhibiting Wnt/-catenin signaling

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JOURNAL OF BIOLOGIcAL cHEMISTRY 2019年第24期294卷 9642-9654页

作者： Guo, Liang Guo, Ying-Ying Li, Bai-Yu Peng, Wan-Qiu Tang, Qi-Qun Fudan Univ Key Lab Metab & Mol Med Minist Educ Dept Biochem & Mol BiolSch Basic Med Sci Shanghai 200032 Peoples R China Fudan Univ Dept Endocrinol & Metab Zhongshan Hosp Shanghai 200032 Peoples R China

beta-catenin signaling is triggered by WNT proteins and is an important pathway that negatively regulates adipogenesis. However, the mechanisms controlling the expression of WNT proteins during adipogenesis remain incompletely understood. Lysine demethylase 5A (KDM5A) is a histone demethylase that removes trimethyl (me3) marks from lysine 4 of histone 3 (H3K4) and serves as a general transcriptional corepressor. Here, using the murine 3T3-L1 preadipocyte differentiation model and an array of biochemical approaches, including chIP, immunoprecipitation, RT-qPcR, and immunoblotting assays, we show that Kdm5a is a target gene of ccAAT/enhancer-binding protein (c/EBP), an important early transcription factor required for adipogenesis. We found that c/EBP binds to the Kdm5a gene promoter and transactivates its expression. We also found that siRNA-mediated KDM5A down-regulation inhibits 3T3-L1 preadipocyte differentiation. The KDM5A knockdown significantly up-regulates the negative regulator of adipogenesis Wnt6, having increased levels of the H3K4me3 mark on its promoter. We further observed that WNT6 knockdown significantly rescues adipogenesis inhibited by the KDM5A knockdown. Moreover, we noted that c/EBP negatively regulates Wnt6 expression by binding to the Wnt6 gene promoter and repressing Wnt6 transcription. Further experiments indicated that KDM5A interacts with c/EBP and that their interaction cooperatively inhibits Wnt6 transcription. Of note, c/EBP knockdown impaired the recruitment of KDM5A to the Wnt6 promoter, which had higher H3K4me3 levels. Our results suggest a mechanism involving c/EBP and KDM5A activities that down-regulates the Wnt/-catenin pathway during 3T3-L1 preadipocyte differentiation.

关键词： adipogenesis ccAAT enhancer-binding protein (c EBP) histone demethylase Wnt signaling beta-catenin (B-catenin) epigenetics post-translational modification (PTM) obesity chromatin immunoprecipitation (chiP) 3T3-L1 preadipocyte adipogenesis c EBPbeta lysine demethylase 5A (KDM5A) Wnt beta-catenin pathway fat cell chIP-on-chip

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Preparation of Li4Ti5O12/c composite by one-step solid state method

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FERROELEcTRIcS 2019年第1期548卷 34-41页

作者： Ma, Guangqiang cheng, Min Panzhihua Univ Panzhihua Peoples R China

The Li4Ti5O12/c composites were synthesized by one-step solid-phase reaction using metatitanic acid, lithium carbonate and sucrose as raw materials. The effects of the molar ratio of lithium to titanium, calcining temperature, calcination time, and sucrose content on the structure of Li4Ti5O12/c composites were studied. XRD, SEM, TEM and electrochemical performance tests were used to characterize the results. The results showed that n(Li):n(Ti) = 0.85, calcination temperature was 750 degrees c, calcination time was 6 h, and the sucrose addition amount was 30% of the total mass of raw materials. Under the conditions, the pure Li4Ti5O12/c composites can be synthesized. The particles are uniform, the particle size is 0.1-1 mu m, and the carbon envelopment is better. The specific capacity is up to 163.94 mAh/g at 0.1 c rate, and the theoretical specific capacity is 175 mAh/g very close.

关键词： Li4Ti5O12 c solid-phase method carbon package

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Ion exchange for enhancing MOF adsorbents performance in humid c 2 H 2 /cO 2 separation

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chinese chemical Letters 2024年

作者： Muzi Li Xin Zhang Xiang-Jing Kong Qiancheng chen Xuefeng Bai Tao He Jian-Rong Li Beijing Key Laboratory for Green Catalysis and Separation and Department of Chemical Engineering College of Materials Science and Engineering Beijing University of Technology Beijing 100124 China

The gas separation performance of metal-organic framework (MOF) adsorbents could be enhanced by tuning the pores, whereas the presence of moisture usually compromises the efficiency. Herein, two MOFs, Fe-BDc-TPT-BF 4 , Ni-BDc-TPT-TMA (TMA +  = (cH 3 ) 4 N + ), were synthesized by exchanging countering ions in parent MOFs, Fe-BDc-TPT-cl and Ni-BDc-TPT-Me 2 NH 2 , respectively. Fe-BDc-TPT-BF 4 and Ni-BDc-TPT-TMA exhibited a high c 2 H 2 adsorption uptake of 203.1 cm 3 /g and 200.1 cm 3 /g at 298 K and 1 bar, and high c 2 H 2 /cO 2 selectivity of 4.6 and 4.4. Humid breakthrough experiments revealed that high c 2 H 2 productivity of high c 2 H 2 purity was achieved on Ni-BDc-TPT-TMA at 35% relative humidity. cycling dynamic breakthrough experiments demonstrate good recyclability of Ni-BDc-TPT-TMA for humid c 2 H 2 /cO 2 separation. The alteration of countering ions changed the pore size and chemistry, leading to high c 2 H 2 uptake, high c 2 H 2 selectivity, and retained performance in the presence of moisture, making it a promising candidate for practical applications. This work highlights that ion exchange modification of MOFs has been developed as a facile and powerful strategy to optimize the inner pores for better performance in challenging separations.

关键词： Metal-organic framework Ion exchange Acetylene purification c 2 H 2 /cO 2 separation Humid condition

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