摘要:
Cadmium (Cd) is a harmful environmental pollutant that disrupts public health, including respiratory, digestive, and reproductive systems. In this study, male rats were exposed to CdCl(2) at a dose of 3mg/kg by oral for 28 days to investigate the impact on spermatogenesis. Testis tissue samples were collected after sacrifice, and piRNA expression levels were measured using piRNA microarray and qPCR. PiRNAs, specialized molecules involved in spermatogenesis, were examined. CdCl(2) exposure led to disrupted piRNA expression, particularly in piRNA-DQ759395 in rats. This piRNA was found to have a binding site with p53, and a similar piRNA-DQ717867 was discovered in mice. In GC-2spd cells, CdCl(2) exposure increased piRNA-DQ717867 expression, which resulted in cell cycle arrest and abnormal expression of cell cycle-related proteins. The activation of p53-related pathways and disruptions in cell cycle regulation were also observed. Antagomir-717867 transfections and PFT-a pretreatment in GC-2spd cells supported the involvement of piRNA-DQ717867 in regulating cell cycle-related proteins. This study suggests that Cd exposure induces abnormal expression of piRNA-DQ759395 in rat testis and that piRNA-DQ717867 may regulate p53, causing cell cycle abnormalities in GC-2spd cells. These findings help understand the mechanisms of male reproductive toxicity caused by Cd exposure and emphasize the role of piRNAs in cell cycle regulation and male reproductive health.
作者机构:
[Qu, Lianqiang] Cent China Normal Univ, Sch Math & Stat, Wuhan 430079, Hubei, Peoples R China.;[Sun, LQ; Sun, Liuquan] Chinese Acad Sci, Inst Appl Math, Acad Math & Syst Sci, Beijing 100190, Peoples R China.;[Sun, Yanqing] Univ North Carolina Charlotte, Dept Math & Stat, 9201 Univ City Blvd, Charlotte, NC 28223 USA.
通讯机构:
[Sun, LQ ] C;Chinese Acad Sci, Inst Appl Math, Acad Math & Syst Sci, Beijing 100190, Peoples R China.
摘要:
Quantile regression has become a widely used tool for analysing competing risk data. However, quantile regression for competing risk data with a continuous mark is still scarce. The mark variable is an extension of cause of failure in a classical competing risk model where cause of failure is replaced by a continuous mark only observed at uncensored failure times. An example of the continuous mark variable is the genetic distance that measures dissimilarity between the infecting virus and the virus contained in the vaccine construct. In this article, we propose a novel mark-specific quantile regression model. The proposed estimation method borrows strength from data in a neighbourhood of a mark and is based on an induced smoothed estimation equation, which is very different from the existing methods for competing risk data with discrete causes. The asymptotic properties of the resulting estimators are established across mark and quantile continuums. In addition, a mark-specific quantile-type vaccine efficacy is proposed and its statistical inference procedures are developed. Simulation studies are conducted to evaluate the finite sample performances of the proposed estimation and hypothesis testing procedures. An application to the first HIV vaccine efficacy trial is provided.
期刊:
ELECTRONIC JOURNAL OF COMBINATORICS,2024年31(1) ISSN:1077-8926
通讯作者:
Li, SC
作者机构:
[Lei, Xingyu; Li, Shuchao; Li, SC] Cent China Normal Univ, Fac Math & Stat, Wuhan 430079, Peoples R China.
通讯机构:
[Li, SC ] C;Cent China Normal Univ, Fac Math & Stat, Wuhan 430079, Peoples R China.
摘要:
For a given graph F, we say that a graph G is F -free if it does not contain F as a subgraph. A graph is color -critical if it contains an edge whose deletion reduces its chromatic number. Let Kr+ (a1, a2,... , ar) be the graph obtained from complete r -partite graph with parts of sizes a1 2, a2, ... , ar, by adding an edge to the first part. In this paper, we focus on the spectral extrema of disjoint colorcritical graphs. For fixed t, a1, ... , ar (r 2) and large enough n, we characterize the unique n -vertex tKr+ (a1, ... , ar)-free graph having the largest spectral radius. Moreover, let F1, ... , Ft be t disjoint color -critical graphs with the same chromatic number. We identify the unique n -vertex Uti=1 Fi-free graph having the largest spectral radius for sufficiently large n. Consequently, we generalize the main results obtained by Ni, Wang and Kang
期刊:
Journal of Functional Analysis,2024年286(2):110206 ISSN:0022-1236
通讯作者:
Xie, HF
作者机构:
[Luo, Peng] Cent China Normal Univ, Sch Math & Stat, Key Lab Nonlinear Anal & Applicat, Minist Educ, Wuhan 430079, Peoples R China.;[Tang, Zhongwei] Beijing Normal Univ, Sch Math Sci, Beijing 100875, Peoples R China.;[Xie, Huafei] Nanyang Normal Univ, Sch Math & Stat, Nanyang 473061, Peoples R China.
通讯机构:
[Xie, HF ] N;Nanyang Normal Univ, Sch Math & Stat, Nanyang 473061, Peoples R China.
摘要:
In this paper we study the following eigenvalue problem {-Delta v = lambda C(alpha)(p(alpha) - epsilon)vertical bar x vertical bar(alpha)u(epsilon)(p alpha-epsilon-1)v in Omega, u=0 on partial derivative Omega, where Omega subset of R-N is a smooth bounded domain containing the origin, C(alpha) = (N + alpha)(N - 2), N >= 3, p(alpha) = N+2+2 alpha/N-2, alpha > 0, epsilon > 0 is a small parameter and u(epsilon) is a single peaked solution of Henon equation {-Delta u = C(alpha)vertical bar x vertical bar(alpha)u(p alpha-epsilon) in Omega, u > 0 in Omega, u=0 on partial derivative Omega, which established by Gladiali and Grossi (2012) [21]. By using various local Pohozaev identities and blow-up analysis, we prove some asymptotic behavior of the eigen values lambda(epsilon,i) and corresponding eigen functions v(epsilon,i), i = 2, ... , Sigma(1 <= k <= 2+alpha/2) (N + 2k - 2) (N + k - 3)!/(N - 2)!k! + 2 when alpha is not an even integer. As a consequence, if 0 < alpha < 2, we have that the Morse index of the single peaked solutions is N + 1, which gives an affirmative answer to a conjecture raised by Gladiali and Grossi. (c) 2023 Elsevier Inc. All rights reserved.
摘要:
Organic molecules bearing chiral sulfur stereocenters exert a great impact on asymmetric catalysis and synthesis, chiral drugs, and chiral materials. Compared with acyclic ones, the catalytic asymmetric synthesis of thio-heterocycles has largely lagged behind due to the lack of efficient synthetic strategies. Here we establish the first modular platform to access chiral thio-oxazolidinones via Pd-catalyzed asymmetric [3+2] annulations of vinylethylene carbonates with sulfinylanilines. This protocol is featured by readily available starting materials, and high enantio- and diastereoselectivity. In particular, an unusual effect of a non-chiral supporting ligand on the diastereoselectivity was observed. Possible reaction mechanisms and stereocontrol models were proposed.
期刊:
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY,2024年72(13):7021-7032 ISSN:0021-8561
通讯作者:
Feng, LL
作者机构:
[Zuo, Lingzi; Fan, Yuxuan; Feng, LL; Feng, Lingling; He, Yanlin; Cheng, Cai; Zhang, Liexiong; Guo, Xiaoliang; Cheng, Guonian; Yu, Jie; Tang, Guangmei; Huang, Shi; Chen, Ruiqing] Cent China Normal Univ, Coll Chem, Key Lab Pesticide & chem Biol CCNU, Minist Educ, Wuhan 430079, Peoples R China.;[Liu, Yanyang; Feng, LL; Feng, Lingling] Wuhan Inst Photochem & Technol, Wuhan 430083, Hubei, Peoples R China.;[Feng, LL; Feng, Lingling] Cent China Normal Univ, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.
通讯机构:
[Feng, LL ] C;Cent China Normal Univ, Coll Chem, Key Lab Pesticide & chem Biol CCNU, Minist Educ, Wuhan 430079, Peoples R China.;Wuhan Inst Photochem & Technol, Wuhan 430083, Hubei, Peoples R China.;Cent China Normal Univ, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.
关键词:
Active substructure splicing;DFT;Harmful cyanobacteria blooms;SAR;algicide;thioacetamide derivatives
摘要:
Lakes and reservoirs worldwide are experiencing a growing problem with harmful cyanobacterial blooms (HCBs), which have significant implications for ecosystem health and water quality. Algaecide is an effective way to control HCBs effectively. In this study, we applied an active substructure splicing strategy for rapid discovery of algicides. Through this strategy, we first optimized the structure of the lead compound S5, designed and synthesized three series of thioacetamide derivatives (series A, B, C), and then evaluated their algicidal activities. Finally, compound A3 with excellent performance was found, which accelerated the process of discovering and developing new algicides. The biological activity assay data showed that A3 had a significant inhibitory effect on M. aeruginosa. FACHB905 (EC(50) = 0.46 μM) and Synechocystis sp. PCC6803 (EC(50) = 0.95 μM), which was better than the commercial algicide prometryn (M. aeruginosa. FACHB905, EC(50) = 6.52 μM; Synechocystis sp. PCC6803, EC(50) = 4.64 μM) as well as better than lead compound S5 (M. aeruginosa. FACHB905, EC(50) = 8.80 μM; Synechocystis sp. PCC6803, EC(50) = 7.70 μM). The relationship between the surface electrostatic potential, chemical reactivity, and global electrophilicity of the compounds and their activities was discussed by density functional theory (DFT). Physiological and biochemical studies have shown that A3 might affect the photosynthesis pathway and antioxidant system in cyanobacteria, resulting in the morphological changes of cyanobacterial cells. Our work demonstrated that A3 might be a promising candidate for the development of novel algicides and provided a new active skeleton for the development of subsequent chemical algicides.
摘要:
Fe-SSZ-13 (Fe -13) is an effectual catalyst for NOx abatement with extensive application potential in the selective reduction of NOx by NH3 (NH3-SCR). It is necessary to further research and expand the fundamental knowledge of Fe -13 catalysts. In this research, Fe -13 zeolites possessing Si/Al ratios of 6.9, 12.0, and 17.5 were prepared. Fe13(6.9) showed excellent catalytic activity because it had a larger number of isolated Fe3+ ions and welldispersed Fe species. Upon hydrothermal aging, the Fe -13(6.9) catalyst diminished significantly in catalytic activity. Among the three, Fe -13(17.5) exhibited the best hydrothermal stability. It is because Fe -13, possessing a higher Si/Al ratio, had fewer Si-OH-Al bonds but more Si(0Al) structures. Thus, Fe -13(17.5) suffered less structural collapse during hydrothermal aging, leading to a smaller decrease in active isolated Fe3+ ions and acid sites, as well as a lower aggregation of Fe species. Moreover, above 200 degrees C, Fe -13(6.9) exhibited a higher reaction rate compared to Fe -13(12.0) and Fe -13(17.5), and the SCR reaction route of Fe -13(6.9) was distinctly different from that of the other two catalysts.
作者机构:
[Qiu, Xiaofeng; Zheng, Juan; Zhu, Xiaoxiao; Zhang, Qian; Guo, Yanbing; Zhu, Yuhua; Chen, Wei; Zhang, Baojian; Guo, YB; Luo, Zhu; Li, Weihao; Pan, Chuanqi; Fang, Yarong; Wang, Jinlong] Cent China Normal Univ, Inst Environm & Appl Chem, Engn Res Ctr Photoenergy Utilizat Pollut Control &, Minist Educ,Coll Chem,Key Lab Pesticide & Chem Bio, Wuhan 430079, Peoples R China.;[Guo, Yanbing; Guo, YB; Luo, Zhu; Wang, Jinlong] Wuhan Inst Photochem & Technol, Wuhan 430082, Peoples R China.;[Wu, Jinsong; Wang, Yutao] Wuhan Univ Technol, Nanostruct Res Ctr, State Key Lab Adv Technol Mat Synth & Proc, Wuhan 430070, Peoples R China.;[Hu, Jinpeng; Wang, Sibo] Fujian Longxin 3D Array Technol Co Ltd, Longyan 364000, Peoples R China.;[Cui, Shuang] SINOPEC Beijing Res Inst Chem Ind Co Ltd, Div Anal, Beijing 100013, Peoples R China.
通讯机构:
[Guo, YB ; Luo, Z] C;Cent China Normal Univ, Inst Environm & Appl Chem, Engn Res Ctr Photoenergy Utilizat Pollut Control &, Minist Educ,Coll Chem,Key Lab Pesticide & Chem Bio, Wuhan 430079, Peoples R China.;Wuhan Inst Photochem & Technol, Wuhan 430082, Peoples R China.
关键词:
(Pt−S−O)-Ti active structure;C3H8 catalytic oxidation;C−H bond activation;Pt-based catalysts;SO2 promotion
摘要:
Typically, SO(2) unavoidably deactivates catalysts in most heterogeneous catalytic oxidations. However, for Pt-based catalysts, SO(2) exhibits an extraordinary boosting effect in propane catalytic oxidation, but the promotive mechanism remains contentious. In this study, an in situ-formed tactful (Pt-S-O)-Ti structure was concluded to be a key factor for Pt/TiO(2) catalysts with a substantial SO(2) tolerance ability. The experiments and theoretical calculations confirm that the high degree of hybridization and orbital coupling between Pt 5d and S 3p orbitals enable more charge transfer from Pt to S species, thus forming the (Pt-S-O)-Ti structure with the oxygen atom dissociated from the chemisorbed O(2) adsorbed on oxygen vacancies. The active oxygen atom in the (Pt-S-O)-Ti active structure is a robust site for C(3)H(8) adsorption, leading to a better C(3)H(8) combustion performance. This work can provide insights into the rational design of chemical bonds for high SO(2) tolerance catalysts, thereby improving economic and environmental benefits.
期刊:
JOURNAL OF MEDICINAL CHEMISTRY,2024年67(8):6822-6838 ISSN:0022-2623
通讯作者:
Guo, J
作者机构:
[Bian, Miao-Miao; Zhang, Ru-Yan; Cui, Hong-Ying; Ding, Dong; Guo, J; Wen, Yu; Guo, Jun; Zhou, Shi-Hao; Zou, Yong-Ke] Cent China Normal Univ, Coll Chem, Int Joint Res Ctr Intelligent Biosensing Technol &, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.
通讯机构:
[Guo, J ] C;Cent China Normal Univ, Coll Chem, Int Joint Res Ctr Intelligent Biosensing Technol &, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.
摘要:
Weak antigens represented by MUC1 are poorly immunogenic, which greatly constrains the development of relevant vaccines. Herein, we developed a multifunctional lipidated protein as a carrier, in which the TLR1/2 agonist Pam(3)CSK(4) was conjugated to the N-terminus of MUC1-loaded carrier protein BSA through pyridoxal 5'-phosphate-mediated transamination reaction. The resulting Pam(3)CSK(4)-BSA-MUC1 conjugate was subsequently incorporated into liposomes, which biomimics the membrane structure of tumor cells. The results indicated that this lipidated protein carrier significantly enhanced antigen uptake by APCs and obviously augmented the retention of the vaccine at the injection site. Compared with the BSA-MUC1 and BSA-MUC1 + Pam(3)CSK(4) groups, Pam(3)CSK(4)-BSA-MUC1 evoked 22- and 11-fold increases in MUC1-specific IgG titers. Importantly, Pam(3)CSK(4)-BSA-MUC1 elicited robust cellular immunity and significantly inhibited tumor growth. This is the first time that lipidated protein was constructed to enhance antigen immunogenicity, and this universal carrier platform exhibits promise for utilization in various vaccines, holding the potential for further clinical application.
作者机构:
[Xu, Yuling; Luo, Lishi; Sun, Yao; Pang, Yida; Yang, Jingfang; Li, Chonglu] Cent China Normal Univ, Coll Chem, Int Joint Res Ctr Intelligent Biosensor Technol &, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.;[Luo, Lishi] Hunan Univ, State Key Lab Chemo Biosensing & Chemometr, Changsha 410082, Peoples R China.;[Sharma, Amit] Amity Univ Punjab, Amity Sch Chem Sci, Dept Phys, Mohali 140306, India.;[Liu, Shuang] Wuhan Univ Technol, Sch Mat Sci & Engn, Wuhan 430070, Peoples R China.;[Zhan, Jianbo] Hubei Prov Ctr Dis Control & Prevent, Inst Hlth Inspect & Testing, Wuhan, Hubei, Peoples R China.
通讯机构:
[Sun, Y ] C;Cent China Normal Univ, Coll Chem, Int Joint Res Ctr Intelligent Biosensor Technol &, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.
摘要:
Albeit sonodynamic therapy (SDT) has achieved encouraging progress in microbial sterilization, the scarcity of guidelines for designing highly effective sonosensitizers and the intricate biofilm microenvironment (BME), substantially hamper the therapeutic efficacy against biofilm infections. To address the bottlenecks, we innovatively design a Ru(II) metallacycle-based sonosensitizer/sonocatalyst (named Ru-A3-TTD) to enhance the potency of sonotherapy by employing molecular engineering strategies tailored to BME. Our approach involves augmenting Ru-A3-TTD’s production of ultrasonic-triggered reactive oxygen species (ROS), surpassing the performance of commercial sonosensitizers, through a straightforward but potent π-expansion approach. Within the BME, Ru-A3-TTD synergistically amplifies sonotherapeutic efficacy via triple-modulated approaches: (i) effective alleviation of hypoxia, leading to increased ROS generation, (ii) disruption of the antioxidant defense system, which shields ROS from glutathione consumption, and (iii) enhanced biofilm penetration, enabling ROS production in deep sites. Notably, Ru-A3-TTD sono-catalytically oxidizes NADPH, a critical coenzyme involved in antioxidant defenses. Consequently, Ru-A3-TTD demonstrates superior biofilm eradication potency against multidrug-resistant Escherichia coli compared to conventional clinical antibiotics, both in vitro and in vivo. To our knowledge, this study represents the pioneering instance of a supramolecular sonosensitizer/sonocatalyst. It provides valuable insights into the structure-activity relationship of sonosensitizers and paves a promising pathway for the treatment of biofilm infections.
期刊:
Journal of Mathematical Analysis and Applications,2024年537(1):128270 ISSN:0022-247X
通讯作者:
Huang, JC
作者机构:
[Chen, Shuang; Huang, Jicai] Cent China Normal Univ, Sch Math & Stat, Wuhan 430079, Hubei, Peoples R China.;[Chen, Shuang; Huang, Jicai] Cent China Normal Univ, Hubei Key Lab Math Sci, Wuhan 430079, Hubei, Peoples R China.
通讯机构:
[Huang, JC ] C;Cent China Normal Univ, Sch Math & Stat, Wuhan 430079, Hubei, Peoples R China.;Cent China Normal Univ, Hubei Key Lab Math Sci, Wuhan 430079, Hubei, Peoples R China.
摘要:
In this paper, we study the destabilization of synchronous periodic solutions for patch models. By applying perturbation theory for matrices, we derive asymptotic expressions of the Floquet spectra and provide a destabilization criterion for synchronous periodic solutions arising from closed orbits or degenerate Hopf bifurcations in terms of period functions. Finally, we apply the main results to the well-known two -patch Holling-Tanner model. (c) 2024 Elsevier Inc. All rights reserved.
期刊:
Journal of Mathematical Biology,2024年88(4):1-30 ISSN:0303-6812
通讯作者:
Lu, M
作者机构:
[Lu, Min; Huang, Jicai; Pan, Qin] Cent China Normal Univ, Sch Math & Stat, Wuhan 430079, Peoples R China.;[Lu, Min; Huang, Jicai; Pan, Qin] Cent China Normal Univ, Key Lab NAA, MOE, Wuhan 430079, Peoples R China.;[Ruan, Shigui] Univ Miami, Dept Math, Coral Gables, FL 33146 USA.
通讯机构:
[Lu, M ] C;Cent China Normal Univ, Sch Math & Stat, Wuhan 430079, Peoples R China.;Cent China Normal Univ, Key Lab NAA, MOE, Wuhan 430079, Peoples R China.
关键词:
Bogdanov–Takens bifurcation;Harvesting;Holling I functional response;Hopf bifurcation;Krill–whale interaction;Predator–prey model
摘要:
In the Antarctic, the whale population had been reduced dramatically due to the unregulated whaling. It was expected that Antarctic krill, the main prey of whales, would grow significantly as a consequence and exploratory krill fishing was practiced in some areas. However, it was found that there has been a substantial decline in abundance of krill since the end of whaling, which is the phenomenon of krill paradox. In this paper, to study the krill–whale interaction we revisit a harvested predator–prey model with Holling I functional response. We find that the model admits at most two positive equilibria. When the two positive equilibria are located in the region
$$\big \{(N,P)|0\le N< 2N_c,\ P\ge 0\big \}$$
, the model exhibits degenerate Bogdanov–Takens bifurcation with codimension up to 3 and Hopf bifurcation with codimension up to 2 by rigorous bifurcation analysis. When the two positive equilibria are located in the region
$$\big \{(N,P)|N>2N_c,\ P\ge 0\big \}$$
, the model has no complex bifurcation phenomenon. When there is one positive equilibrium on each side of
$$N=2N_c$$
, the model undergoes Hopf bifurcation with codimension up to 2. Moreover, numerical simulation reveals that the model not only can exhibit the krill paradox phenomenon but also has three limit cycles, with the outmost one crosses the line
$$N=2N_c$$
under some specific parameter conditions.
作者:
Banerjee, Malay;Huang, Jicai;Pan, Qin;Zou, Lan
期刊:
DISCRETE AND CONTINUOUS DYNAMICAL SYSTEMS-SERIES B,2024年 ISSN:1531-3492
通讯作者:
Zou, L
作者机构:
[Banerjee, Malay] IIT Kanpur, Dept Math & Stat, Kanpur 208016, India.;[Huang, Jicai; Pan, Qin] Cent China Normal Univ, Sch Math & Stat, Wuhan 430079, Hubei, Peoples R China.;[Zou, Lan; Zou, L] Capital Normal Univ, Sch Math Sci, Beijing 100089, Peoples R China.
通讯机构:
[Zou, L ] C;Capital Normal Univ, Sch Math Sci, Beijing 100089, Peoples R China.
关键词:
Key words and phrases. Generalist predator;stability;limit cycle;Hopf bifurcation;Bogdanov- Takens bifurcation
摘要:
. Consideration of generalist predators leads to relatively complex dynamics due to alternative food sources. Here, we propose and analyze a prey-predator model with a generalist predator. The availability of alternative food sources for the predator and a density-dependent growth rate induces not only bistability and tristability, but also more complicated dynamical behaviors. We have studied the possible number and geometric configurations of positive equilibria in detail. A systematic bifurcation analysis has revealed the existence of the degenerate Bogdanov-Takens bifurcation of codimension four and degenerate Hopf bifurcation of codimension three. We found that degenerate local bifurcations with a higher codimension are responsible for three limit cycles. Derivation of the analytical conditions for three limit cycles for a suitable range of parameters is a crucial finding of this work.
期刊:
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY,2024年311:123979 ISSN:1386-1425
通讯作者:
Liu, SH;Zhang, J
作者机构:
[Peng, Zhen; Liu, Sheng Hua; Liu, SH] Cent China Normal Univ, Coll Chem, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.;[Zhang, Jing; Feng, Na; Zhang, J] Southern Med Univ, Nanfang Hosp, Dept Lab Med, Guangzhou 510515, Peoples R China.;[Zhang, Jianyu] Hong Kong Univ Sci & Technol, Hong Kong Branch, Chinese Natl Engn Res Ctr Tissue Restorat & Recons, Dept Chem,Kowloon, Clear Water Bay, Hong Kong 999077, Peoples R China.;[Zhang, Jianyu] Hong Kong Univ Sci & Technol, Inst Adv Study, Kowloon, Clear Water Bay, Hong Kong 999077, Peoples R China.
通讯机构:
[Liu, SH ] C;[Zhang, J ] S;Cent China Normal Univ, Coll Chem, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.;Southern Med Univ, Nanfang Hosp, Dept Lab Med, Guangzhou 510515, Peoples R China.
摘要:
High-performance luminescent gold(I) complexes have attracted considerable attention due to their potential applications in various fields, but their construction is a significantly challenging task. Herein, we designed and synthesized a series of novel dinuclear gold(I) complexes 1-4 based on 1,2-bis(diphenylphosphino)benzene and 1,4-bis(diphenylphosphino)benzene frameworks, where para-substitutions of benzene ring were employed for comparison and bulky t-butyl groups were introduced into carbazole ligands to assist flexibly regulating the aurophilicity. Among them, the structure of complex 1 was confirmed by single-crystal X-ray diffraction, and all the complexes exhibited typical aggregation-induced emission characteristics. Due to the construction of intramolecular aurophilicity and the formation of molecular clusters, noticeable enhancement of the luminescent efficiency was achieved for the core complex 1. Together with the introduction of flexible t-butyl groups, good responsiveness towards external mechanical force and solvent vapors were also realized. Moreover, the specific bioimaging ability of complex 1 towards cancer cells was demonstrated. Thus, this work presents the crucial capability of aurophilic manipulation in tuning the luminescence and smart behaviors of gold complexes, and it will open a new route to developing high-performance luminescent materials.
期刊:
Landscape and Urban Planning,2024年241:104924 ISSN:0169-2046
通讯作者:
Xiao, CW
作者机构:
[Wang, Yi; Xiao, Chiwei; Xiao, CW; Yan, Mingyan; Chiaka, Jeffrey Chiwuikem] Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A Datun Rd, Beijing, Peoples R China.;[Wang, Yi; Xiao, Chiwei; Xiao, CW] Univ Chinese Acad Sci, Coll Resources & Environm, 1 Yanqihu East Rd, Beijing, Peoples R China.;[Wang, Yi; Yan, Mingyan] Cent China Normal Univ, Coll Publ Adm, 382 Luoyu Rd, Wuhan, Peoples R China.;[Chiaka, Jeffrey Chiwuikem] Beijing Normal Univ, Sch Environm, 19 Xinjiekou, Beijing, Peoples R China.
通讯机构:
[Xiao, CW ] C;Chinese Acad Sci, Inst Geog Sci & Nat Resources Res, 11A Datun Rd, Beijing, Peoples R China.;Univ Chinese Acad Sci, Coll Resources & Environm, 1 Yanqihu East Rd, Beijing, Peoples R China.
关键词:
Land -use change;Landscape pattern;Geo-economic cooperation;Cross-border transportation corridors;China -Laos Railway
摘要:
Regional integration initiatives have triggered impacts on land use changes (LUC) and landscape patterns through geo-economic cooperation like cross-border infrastructure, which are often presented, but comprehensive studies on the extent and degree remains insufficient. The China-Laos Railway (CLR), a cross-border transportation corridor connecting Kunming in China with the Laotian capital, Vientiane, which was launched in December 2016 and operation started in December 2021, has recently witnessed rapid and notable changes in landscape and land use. This case study provides a distinctive opportunity to evaluate the relative significance of political and socioeconomic factors on LUC and landscape patterns. In this study, we integrate 10-m land-use data products (2017–2022) provided by Environmental Systems Research Institute, Inc (ESRI) with geospatial analysis to quantify and compare the impacts of cross-border transportation corridors on LUC within a 10 km buffer area along the CLR. The results showed that since 2017, about 3 % deforestation caused by the expansion of cropland (8 %) and construction land (38 %) along the CLR. The comprehensive dynamic degree along the CLR displays two peaks, appearing within the 2–4 km and 8–10 km buffer zones. Interestingly, the fragmentation of land patches within the buffer zone decreases as the distance from the CLR increases. Moreover, the construction of the CLR has a greater impact on the Laotian side, while its completion and operation triggered more significant changes on the Chinese side. The study quantitatively assesses the extent, type, and intensity of the impacts of cross-border transportation corridors on LUC and landscape patterns.
摘要:
Regioselective 1,2-dichalcogenation of alkenes has attracted significant attention in modern organic synthetic chemistry. While there are a plethora of methods to access alkene dichalcogenated architectures, sulfonylsulfination of alkenes is extremely challenging due to the inherent characteristics of the sulfur atom. Herein, a multicomponent fragment coupling of alkenes, sulfinates, and DABSO was developed to construct densely functionalized sulfonylsulfinated products, which are otherwise challenging to access, with broad substrate scope and group tolerance under mild and operationally simple conditions, using an inexpensive 100-1000 ppm organic photocatalyst. In addition, the protocol was applied to the late-stage functionalization of complex molecules, and the obtained products were converted into diverse downstream transformations to demonstrate their synthetic potential. Experimental and theoretical mechanistic investigations suggest that these reactions proceed through sequential sulfonyl and sulfinyl oxygen radical mutual transformations and radical-polar crossover coupling. This strategy provides access to previously inaccessible alkene sulfonylsulfinated products in good-to-high regio- and stereoselectivity, along with opening up previously unexplored synthetic directions.
期刊:
Journal of Soils and Sediments,2024年24(1):1-16 ISSN:1439-0108
通讯作者:
Liu, Muxing;Yi, J
作者机构:
[Yi, Jun; Lu, Shiguo; Liu, Muxing; Zhang, Hailin; Liu, MX; Wang, Weijie] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Peoples R China.;[Yi, Jun; Lu, Shiguo; Liu, Muxing; Zhang, Hailin; Liu, MX; Wang, Weijie] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Peoples R China.;[Wan, Jinhong] Inst Water Resources & Hydropower Res, Beijing 100048, Peoples R China.
通讯机构:
[Yi, J ; Liu, MX] C;Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Peoples R China.;Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Peoples R China.
关键词:
Soil infiltration response;Forest conversion;Hillslope hydrology;Humid area
摘要:
PurposeUnderstanding the characteristics of soil infiltration response to rainfall is critical for soil water transport processes and hydrologic modeling. However, little is known about how they vary with forest conversion at different temporal stages (< 20 years) below the rooting zone. Therefore, this study aims to investigate soil infiltration response patterns in different subtropical forest conversion hillslopes, including mature original forest (thick root), young secondary forest (middle root), and very young secondary grassland (fine root), and analyzed the effects of environmental factors on the dynamics of soil infiltration.Materials and methodsSeveral metrics were evaluated to characterize and quantify the nature of these responses by estimating changes in the soil water content, the response time difference between two adjacent soil depths, and infiltration velocities for 1144 infiltration events at 6 locations on the three hillslopes.Results and discussionSoil infiltration responses were similar on both forestland hillslopes, yet significantly different from those on the grassland hillslope. The preferential flow was more evident in the profile of thick-rooted vegetation, and the velocity of the wetting front was faster in the profiles of middle- and fine-rooted vegetation. Topography and root characteristics interact to influence soil infiltration response at the hillslope scale.ConclusionsConversion from thick-rooted forests into fine-rooted grasslands altered the rainfall-related soil infiltration dynamics below the rooting zone. In particular, the occurrence of preferential flow and infiltration rates varied, which helps enhance our understanding of ecohydrological processes in the context of changing land use and hydroclimatic conditions.
作者机构:
[Liu, Lijuan; Zhang, Lizhi; Gong, JM; Meng, Mingxia; Gong, Jingming; Yao, Qingfeng; Cai, Zheng; Sun, Hongwei; Jiang, Fang] Cent China Normal Univ, Int Joint Res Ctr Intelligent Biosensing Technol &, Key Lab Pesticide & Chem Biol, Coll Chem,Minist Educ, Wuhan 430079, Peoples R China.
通讯机构:
[Gong, JM ] C;Cent China Normal Univ, Int Joint Res Ctr Intelligent Biosensing Technol &, Key Lab Pesticide & Chem Biol, Coll Chem,Minist Educ, Wuhan 430079, Peoples R China.
摘要:
As emerging contaminants in the environment, antibiotic resistance genes (ARGs) have aroused a global health crisis and posed a serious threat to ecological safety and human health. Thus, efficient and accurate onsite detection of ARGs is crucial for environmental surveillance. Here, we presented a colorimetric-photoelectrochemical (PEC) dual-mode bioassay for simultaneous detection of multiple ARGs by smartly incorporating rolling circle amplification (RCA) into a stimuli-responsive DNA nanoassembly, using the tetracycline resistance genes tetA and tetC as models. The tailored DNA nanoassembly containing RCA amplicons hybridized with specific signal probes: CuO nanoflowers-anchored signal DNA1 and HgO nanoparticles-anchored signal DNA2, respectively. Upon exposure to an acidic stimulus, numerous Cu(2+) and Hg(2+) were released, serving as the reporting agent of colorimetric/PEC dual-mode assay. The released Cu(2+) and Hg(2+) induced localized surface plasmon resonance shifts in Au nanorods and triangular Ag nanoplates through an etching process, respectively, enabling visual analysis of ARGs with distinguishing color changes. Meanwhile, numerous Cu(2+) and Hg(2+) triggered the amplified PEC variations via reacting with the photoactive layers of CuS/CdS and ZnS, respectively. Thus, a rapid and ultrasensitive colorimetric/PEC dual-mode detection of multiple ARGs was achieved with the detection limit down to 17.2 aM. Furthermore, such dual-mode bioassay could discriminate single-base mismatch and successfully determine ARGs in E. coli plasmids and sludge samples, holding great promise for point-of-care genetic diagnostics.
作者机构:
[Kong, Sheng; Yi, Beibei; Guo, R; Ma, Yujiao; Guo, Rui; Zhang, Guozhu; Du, Qianqian; Zhang, He; Zhang, GZ; Zheng, Jialian] Cent China Normal Univ CCNU, Int Joint Res Ctr Intelligent Biosensing Technol &, CCNU uOttawa Joint Res Ctr, Key Lab Pesticides & Chem Biol,Minist Educ,Coll Ch, Wuhan 430079, Hubei, Peoples R China.
通讯机构:
[Guo, R ; Zhang, GZ] C;Cent China Normal Univ CCNU, Int Joint Res Ctr Intelligent Biosensing Technol &, CCNU uOttawa Joint Res Ctr, Key Lab Pesticides & Chem Biol,Minist Educ,Coll Ch, Wuhan 430079, Hubei, Peoples R China.
关键词:
Amines;Silylation;Copper catalysis;Hydrogen atom transfer;C−H activation
摘要:
The development of a general and selective method for alpha-C-(sp(3))-H silylation of feedstock amines has been a long-standing challenge. In this paper, we disclose a mild, general, practical, and highly regio- and diastereoselective alpha-C-(sp(3))-H silylation of various readily available acyclic, cyclic, and aromatic amines with silylboranes through a copper-catalyzed intramolecular 1,5-hydrogen atom transfer (HAT) strategy. The mild activation of 2-iodobenzamide to generate an aryl radical enabled by a ligand-coordinated silyl copper complex without additional heating or photoinduced conditions, as well as the intramolecular selective 1,5-HAT process to produce the crucial alpha-aminoalkyl radical species, is the key to the success of this chemistry. This silylation protocol has demonstrated its potential utility in the late-stage modification of structurally complex drugs and bioactive molecules. Therefore, it is expected that this method will find applications in synthetic chemistry and drug discovery.
期刊:
Science of The Total Environment,2024年908:167878 ISSN:0048-9697
通讯作者:
Hao, GF
作者机构:
[Zhao, Wei; Zhang, Xiao; Hao, Ge-Fei; Gao, Yang-Yang; Huang, Yuan-Qin; Kumar, Vinit] Guizhou Univ, Ctr Res & Dev Fine Chem, Natl Key Lab Green Pesticide, Key Lab Green Pesticide & Agr Bioengn,Minist Educ, Guiyang 550025, Peoples R China.;[Hao, Ge-Fei] Cent China Normal Univ, Natl Key Lab Green Pesticide, Wuhan 430079, Peoples R China.
通讯机构:
[Hao, GF ] G;Guizhou Univ, Ctr Res & Dev Fine Chem, Natl Key Lab Green Pesticide, Key Lab Green Pesticide & Agr Bioengn,Minist Educ, Guiyang 550025, Peoples R China.
摘要:
Pesticides are indispensable to maintain crop quality and food production worldwide, but their use also poses environmental risks. Pesticide risk assessment involves a series of complex, expensive and time-consuming toxicity tests. To improve the efficiency and accuracy for assessing the environmental impact of pesticides, numerous computational tools have been developed. However, there is a notable deficiency in critical analysis or a systematic summary of environmental risk assessment tools and their applicable contexts. Here, many of the current approaches and tools for assessing environmental risks posed by pesticides are reviewed, and the question of whether these tools are fit for use on complex multicomponent scenarios is discussed. We analyze the adaptations of these tools to aquatic and terrestrial ecosystems, followed by the provision of resources for predicting pesticide concentrations in environmental medias, including air, soil and water. The successful application of computational tools for risk assessment and interpretation of predicted results will also be discussed. This assessment serves as a valuable resource, enabling scientists to utilize suitable models to enhance the robustness of pesticides risk assessments.