Month: February 2022

Product Details of 86-92-0. Recently I am researching about DNA-BINDING; PLASMODIUM-FALCIPARUM; COPPER(II) COMPLEXES; CU(II) COMPLEXES; DERIVATIVES; ANTICANCER; BINARY, Saw an article supported by the . Published in PERGAMON-ELSEVIER SCIENCE LTD in OXFORD ,Authors: Shaikh, I; Jadeja, RN; Patel, R. The CAS is 86-92-0. Through research, I have a further understanding and discovery of 3-Methyl-1-p-tolyl-5-pyrazolone

Three novel mixed ligand Zn(II) complexes {complex 1 = [Zn(L1)(2)(bpy)], complex 2 = [Zn(L2)(2)(bPY)], complex 3 = [Zn(L2)(2)(phen)], where bpy = 2,2′-bipyridine and phen = 1,10-phenanthroline} of 4-(4-chlorobenzoyl)-2-(3-chlorophenyl)-5-methyl-2,4-dihydro-3H-pyrazol-3-one (HL1) and 4-(4-chlorobenzoyl)-5-methyl-2-(p-tolyl)-2,4-dihydro-3H-pyrazol-3-one (HL2) were synthesized and characterized by H-1 and C-13 NMR, FTIR, TG-DTA, UV-Vis, elemental analysis, molar conductance and single crystal X-ray structure determination. Based on analytical and spectroscopic techniques, all the three Zn(II) complexes were found to have a distorted octahedral geometry. The ligands and the complexes were screened for antimalarial activity against plasmodium falciparum. The zinc(II) complexes showed greater antimalarial activity than their parent ligands. (C) 2020 Elsevier Ltd. All rights reserved.

Product Details of 86-92-0. Welcome to talk about 86-92-0, If you have any questions, you can contact Shaikh, I; Jadeja, RN; Patel, R or send Email.

Reference:
Article; Zhang, Yong; Nie, Long-Jun; Luo, Liang; Mao, Jia-Xin; Liu, Jin-Xiang; Xu, Guo-Hai; Chen, Deliang; Luo, Hai-Qing; Tetrahedron; vol. 76; 7; (2020);,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Computed Properties of C12H12N2O3. Shankar-Hari, M; Saha, R; Wilson, J; Prescott, HC; Harrison, D; Rowan, K; Rubenfeld, GD; Adhikari, NKJ in [Shankar-Hari, Manu; Wilson, Julie] St Thomas Hosp, Guys & St Thomas NHS Fdn Trust, ICU Support Off, 1st Floor,East Wing, London SE1 7EH, England; [Shankar-Hari, Manu; Saha, Rohit] Kings Coll London, Sch Immunol & Microbial Sci, London SE1 9RT, England; [Shankar-Hari, Manu; Harrison, David; Rowan, Kathryn] Intens Care Natl Audit & Res Ctr, Napier House,24 High Holborn, London WC1V 6AZ, England; [Prescott, Hallie C.] Div Pulm & Crit Care Med, Ann Arbor, MI 48109 USA; [Prescott, Hallie C.] Univ Michigan Hlth Syst, VA Ctr Clin Management Res, Ann Arbor, MI USA; [Rubenfeld, Gordon D.; Adhikari, Neill K. J.] Univ Toronto, Interdept Div Crit Care Med, Toronto, ON M4N 3M5, Canada; [Rubenfeld, Gordon D.; Adhikari, Neill K. J.] Sunnybrook Hlth Sci Ctr, Dept Crit Care Med, 2075 Bayview Ave,D1-08, Toronto, ON M4N 3M5, Canada published Rate and risk factors for rehospitalisation in sepsis survivors: systematic review and meta-analysis in 2020, Cited 86. The Name is 1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carboxylic acid. Through research, I have a further understanding and discovery of 83-10-3.

Purpose Sepsis survivors have a higher risk of rehospitalisation and of long-term mortality. We assessed the rate, diagnosis, and independent predictors for rehospitalisation in adult sepsis survivors. Methods We searched for non-randomized studies and randomized clinical trials in MEDLINE, Cochrane Library, Web of Science, and EMBASE (OVID interface, 1992-October 2019). The search strategy used controlled vocabulary terms and text words for sepsis and hospital readmission, limited to humans, and English language. Two authors independently selected studies and extracted data using predefined criteria and data extraction forms. Results The literature search identified 12,544 records. Among 56 studies (36 full and 20 conference abstracts) that met our inclusion criteria, all were non-randomised studies. Studies most often report 30-day rehospitalisation rate (mean 21.4%, 95% confidence interval [CI] 17.6-25.4%; N = 36 studies reporting 6,729,617 patients). The mean (95%CI) rehospitalisation rates increased from 9.3% (8.3-10.3%) by 7 days to 39.0% (22.0-59.4%) by 365 days. Infection was the most common rehospitalisation diagnosis. Risk factors that increased the rehospitalisation risk in sepsis survivors were generic characteristics such as older age, male, comorbidities, non-elective admissions, hospitalisation prior to index sepsis admission, and sepsis characteristics such as infection and illness severity, with hospital characteristics showing inconsistent associations. The overall certainty of evidence was moderate for rehospitalisation rates and low for risk factors. Conclusions Rehospitalisation events are common in sepsis survivors, with one in five rehospitalisation events occurring within 30 days of hospital discharge following an index sepsis admission. The generic and sepsis-specific characteristics at index sepsis admission are commonly reported risk factors for rehospitalisation. Registration PROSPERO CRD 42016039257, registered on 14-06-2016.

Computed Properties of C12H12N2O3. Bye, fridends, I hope you can learn more about C12H12N2O3, If you have any questions, you can browse other blog as well. See you lster.

Reference:
Patent; Shanghai Pharmaceutical Industry Institute; China Pharmaceutical Industry Zongyuan; Li Jianqi; Huang Daowei; Wang Wenya; Zhang Zhiguo; Jiang Ling; (45 pag.)CN107286140; (2017); A;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

COA of Formula: C12H12N2O3. Authors Zhou, L; Yan, JX; Huang, JL; Wang, HB; Wang, XG; Wang, ZJ in ELSEVIER SCI LTD published article about in [Zhou, Liang; Yan, Junxiao; Huang, Julong; Wang, Hongbo; Wang, Xingang; Wang, Zhenjun] Changan Univ, Sch Mat Sci & Engn, Xian 710064, Peoples R China; [Zhou, Liang; Wang, Hongbo; Wang, Xingang; Wang, Zhenjun] Changan Univ, Minist Educ, Engn Res Ctr Transportat Mat, Xian 710061, Peoples R China in 2021, Cited 46. The Name is 1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carboxylic acid. Through research, I have a further understanding and discovery of 83-10-3

Here in, the effects of FeSiAl particle size on the dielectric and microwave absorption properties of FeSiAl/Al2O3 composites were studied. FeSiAl/Al2O3 composites containing 18-25 mu m, 25-48 mu m, and 48-75 mu m FeSiAl particles were prepared by hot-pressed sintering based on uniformly mixed FeSiAl and Al2O3 powders. Results show that the real permittivity and the imaginary permittivity are significantly promoted with increasing FeSiAl particle size, which is ascribed to the enhanced interfacial polarization and conductance loss. In addition, the favorable matching impedance and suitable attenuation coefficient enabled the composite containing 25-48 mu m FeSiAl powder to show a minimum reflection loss of -34.4 dB at 11.7 GHz and an effective absorption bandwidth (<-10 dB) of 1.4 GHz in 11.0-12.4 GHz, when the thickness is 1.1 mm. By adjusting the thickness to 1.4 mm, the effective absorption bandwidth of the composite reaches a maximum value of 2.0 GHz in the 8.3-10.3 GHz range, indicating tunable, strong, and highly efficient microwave absorption performance. COA of Formula: C12H12N2O3. Bye, fridends, I hope you can learn more about C12H12N2O3, If you have any questions, you can browse other blog as well. See you lster.

Reference:
Patent; Shanghai Pharmaceutical Industry Institute; China Pharmaceutical Industry Zongyuan; Li Jianqi; Huang Daowei; Wang Wenya; Zhang Zhiguo; Jiang Ling; (45 pag.)CN107286140; (2017); A;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Name: 3,5-Dimethyl-1H-pyrazole. In 2019.0 CHEM COMMUN published article about METAL-FREE; FUNCTIONALIZATION; IMIDAZOHETEROCYCLES; DIFUNCTIONALIZATION; THIOCYANATION; SULFENYLATION; INHIBITORS; AMINATION; PYRIDINES; RADICALS in [Yu, Yi; Liu, Huilin; He, Min; Yang, Mingzhu; Liu, Pan; Yu, Banying; Dong, Xuanchi; Lei, Aiwen] Jiangxi Normal Univ, Natl Res Ctr Carbohydrate Synth, Nanchang 330022, Jiangxi, Peoples R China; [Yuan, Yong; Lei, Aiwen] Wuhan Univ, IAS, Coll Chem & Mol Sci, Wuhan 430072, Hubei, Peoples R China in 2019.0, Cited 59.0. The Name is 3,5-Dimethyl-1H-pyrazole. Through research, I have a further understanding and discovery of 67-51-6.

Under metal catalyst-free and exogenous-oxidant-free conditions, a series of C-3 aminated imidazo[1,2-a]pyridines were synthesized by electrochemical intermolecular oxidative C-H/N-H cross-coupling. Furthermore, by using a catalytic amount of ferrocene as the mediator, electrochemical intramolecular oxidative C-H/N-H cross-coupling for the synthesis of 10H-benzo[4,5] imidazo[1,2-a]indole derivatives has also been accomplished.

Name: 3,5-Dimethyl-1H-pyrazole. Welcome to talk about 67-51-6, If you have any questions, you can contact Yu, Y; Yuan, Y; Liu, HL; He, M; Yang, MZ; Liu, P; Yu, BY; Dong, XC; Lei, AW or send Email.

Reference:
Pyrazole – Wikipedia,
,Pyrazoles – an overview | ScienceDirect Topics

An article Synthesis of pyrazolones and pyrazoles via Pd-catalyzed aerobic oxidative dehydrogenation WOS:000466245000011 published article about AGENTS; DERIVATIVES in [Zhu, Ye-Fu; Wei, Bo-Le; Wei, Jiao-Jiao; Wang, Wen-Qiong; Song, Wei-Bin; Xuan, Li-Jiang] Chinese Acad Sci, Shanghai Inst Mat Med, State Key Lab Drug Res, 501 Haike Rd,Zhangjiang Hitech Pk, Shanghai 201203, Peoples R China; [Zhu, Ye-Fu; Wei, Bo-Le; Wei, Jiao-Jiao] Univ Chinese Acad Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China in 2019, Cited 18. The Name is 3-Methyl-1-p-tolyl-5-pyrazolone. Through research, I have a further understanding and discovery of 86-92-0. Product Details of 86-92-0

A palladium-catalyzed oxidative dehydrogenation reaction in the presence of AMS and base to synthesize pyrazolones and pyrazoles was identified. This method can be utilized to a wide range of substrates, operates under mild react conditions and can give high yields. We believe it could be used as an alternative protocol for the classical dehydrogenation reactions. (C) 2019 Published by Elsevier Ltd.

Welcome to talk about 86-92-0, If you have any questions, you can contact Zhu, YF; Wei, BL; Wei, JJ; Wang, WQ; Song, WB; Xuan, LJ or send Email.. Product Details of 86-92-0

Reference:
Article; Zhang, Yong; Nie, Long-Jun; Luo, Liang; Mao, Jia-Xin; Liu, Jin-Xiang; Xu, Guo-Hai; Chen, Deliang; Luo, Hai-Qing; Tetrahedron; vol. 76; 7; (2020);,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

An article Asymmetric Organocatalysis Combined with Palladium Catalysis: Synergistic Effect on Enantioselective Mannich/alpha-Allylation Sequential Reactions of Pyrazolones in Constructing Vicinal Quaternary Stereocenters WOS:000489200100005 published article about ALLYLIC DEAROMATIZATION REACTION; STEREOCONTROLLED CONSTRUCTION; MICHAEL ADDITION; ALKYLATION; ACID; PYRAZOLIN-5-ONES; PYRAZOL-5-ONES; ALCOHOLS; BEARING in [Wu, Gengxin; Xu, Haohan; Liu, Ziran; Liu, Yonghong; Yang, Xiang; Huang, Yan] Xinjiang Univ, Coll Chem & Chem Engn, Key Lab Oil & Gas Fine Chem, Minist Educ & Xinjiang Uyghur Autonomous Reg, Urumqi 830000, Xinjiang, Peoples R China; [Zhang, Xulong] Xinjiang Uygur Autonomous Reg Prod Qual Supervis, Urumqi 830000, Xinjiang, Peoples R China in 2019, Cited 46. Computed Properties of C11H12N2O. The Name is 3-Methyl-1-p-tolyl-5-pyrazolone. Through research, I have a further understanding and discovery of 86-92-0

In this letter, an efficient one-pot asymmetric sequential reaction is achieved by organo/transition metal relay catalysis in constructing two consecutive C-C bonds, which involves enantioselective amino squaramide catalytic Mannich-type addition of pyrazolones to isatin-derived ketimines and a subsequent palladium catalyzed diastereoselective allylic alkylation of pyrazolones with allylic acetates. An array of novel pyrazolone-aminooxindole-propylene structural motifs are obtained in a high level of yield and with excellent enantio- and diastereoselectivity (up to 95% yield, >20:1 dr, >99% ee). This methodology features the formation of vicinal quarternary carbon-stereocenters, and the second all-carbon tetrasubstituted stereogenic center is induced by joint action of the achiral palladium catalysis and the chiral environment generated from the Mannich step. Moreover, the usefulness of this methodology is highlighted by converting the allylic product into the carbonyl compound.

Computed Properties of C11H12N2O. Bye, fridends, I hope you can learn more about C11H12N2O, If you have any questions, you can browse other blog as well. See you lster.

Reference:
Article; Zhang, Yong; Nie, Long-Jun; Luo, Liang; Mao, Jia-Xin; Liu, Jin-Xiang; Xu, Guo-Hai; Chen, Deliang; Luo, Hai-Qing; Tetrahedron; vol. 76; 7; (2020);,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

An article Potentially inappropriate prescribing in dementia, multi-morbidity and incidence of adverse health outcomes WOS:000649434300024 published article about DRUG-REACTIONS; MEDICATION USE; OLDER-PEOPLE; CARE; COMORBIDITIES in [Delgado, Joao; Jones, Lindsay; Ballard, Clive; Melzer, David] Univ Exeter, Coll Med & Hlth, Epidemiol & Publ Hlth, Exeter EX1 2LU, Devon, England; [Bradley, Marie C.] US FDA, Off Surveillance & Epidemiol, Ctr Drug Evaluat & Res, Silver Spring, MD 20993 USA; [Allan, Louise M.; Clare, Linda] Univ Exeter, Coll Med & Hlth, Ctr Res Ageing & Cognit Hlth, Exeter EX1 2LU, Devon, England; [Fortinsky, Richard H.] Univ Connecticut, Sch Med, Ctr Aging, Mansfield, CT 06030 USA; [Hughes, Carmel M.] Queens Univ Belfast, Med Biol Ctr, Sch Pharm, Belfast BT9 7BL, Antrim, North Ireland in 2021, Cited 30. The Name is 1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carboxylic acid. Through research, I have a further understanding and discovery of 83-10-3. Application In Synthesis of 1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carboxylic acid

Importance: treatment of dementia in individuals with comorbidities is complex, leading to potentially inappropriate prescribing (PIP). The impact of PIP in this population is unknown. Objective: to estimate the rate of PIP and its effect on adverse health outcomes (AHO). Design: retrospective cohort. Setting: primary care electronic health records linked to hospital discharge data from England. Subjects: 11,175 individuals with dementia aged over 65 years in 2016 and 43,463 age- and sex-matched controls. Methods: Screening Tool of Older Persons’ Prescriptions V2 defined PIP. Logistic regression tested associations with comorbidities at baseline, and survival analyses risk of incident AHO, adjusted for age, gender, deprivation and 14 comorbidities. Results: the dementia group had increased risk of PIP (73% prevalence; odds ratio [OR]: 1.92; confidence interval [CI]: 83-103%; P < 0.01) after adjusting for comorbidities. Most frequent PIP criteria were related to anti-cholinergic drugs and therapeutic duplication. Risk of PIP was higher in patients also diagnosed with coronary-heart disease (odds OR: 2.17; CI: 1.91-2.46; P < 0.01), severe mental illness (OR: 2.09; CI: 1.62-2.70; P < 0.01); and depression (OR: 1.81; CI: 1.62-2.01; P < 0.01). During follow-up (1 year), PIP was associated with increased all-cause mortality (hazard ratio: 1.14; CI: 1.021.26; P < 0.02), skin ulcer and pressure sores (hazard ratio: 1.66; CI: 1.12-2.46; P< 0.01), falls (hazard ratio: 1.37; CI: 1.15-1.63; P < 0.01), anaemia (hazard ratio: 1.61; CI: 1.10-2.38; P < 0.02) and osteoporosis (hazard ratio: 1.62; CI: 1.022.57; P < 0.04). Conclusion: patients with dementia frequently receive PIPs, and those who do are more likely to experience AHO. These results highlight the need to optimise medication in dementia patients, especially those with comorbidities. Application In Synthesis of 1,5-Dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazole-4-carboxylic acid. Welcome to talk about 83-10-3, If you have any questions, you can contact Delgado, J; Jones, L; Bradley, MC; Allan, LM; Ballard, C; Clare, L; Fortinsky, RH; Hughes, CM; Melzer, D or send Email.

Reference:
Patent; Shanghai Pharmaceutical Industry Institute; China Pharmaceutical Industry Zongyuan; Li Jianqi; Huang Daowei; Wang Wenya; Zhang Zhiguo; Jiang Ling; (45 pag.)CN107286140; (2017); A;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

I found the field of Thermodynamics; Chemistry very interesting. Saw the article Benchmark properties of pyrazole derivatives as a potential liquid organic hydrogen carrier: Evaluation of thermochemical data with complementary experimental and computational methods published in 2019.0. Name: 3,5-Dimethyl-1H-pyrazole, Reprint Addresses Verevkin, SP (corresponding author), Samara State Tech Univ, Chem Dept, Samara 443100, Russia.. The CAS is 67-51-6. Through research, I have a further understanding and discovery of 3,5-Dimethyl-1H-pyrazole

The standard molar enthalpies of vaporization of alkyl-pyrazoles were derived from their vapor pressure-temperature dependence measured by the transpiration method as well as indirectly using solution calorimetry. Thermodynamic data on vaporization processes available in the literature were collected, evaluated, and combined with our own experimental results. Additional combustion experiments on the highly pure 1-methyl-pyrazoles helped to resolve ambiguity in the enthalpy of formation for this compound. We have evaluated and recommended a set of vaporization and formation enthalpies for the alkyl-pyrazoles at 298.15 K as the reliable benchmark properties for further thermochemical calculations. Gas phase molar enthalpies of formation of alkyl-pyrazoles calculated by the high-level quantum-chemical G4 and G3MP2 methods were in an excellent agreement with the recommended experimental data. The hydrogenation/dehydrogenation reaction enthalpies of alkyl-pyrazoles were calculated and compared with the data for other potential liquid organic hydrogen carriers. (C) 2018 Elsevier Ltd.

Welcome to talk about 67-51-6, If you have any questions, you can contact Safronov, SP; Nagrimanov, RN; Samatov, AA; Emel’yanenko, VN; Zaitsau, DH; Pimerzin, AA; Skrzypczak, A; Verevkin, SP or send Email.. Name: 3,5-Dimethyl-1H-pyrazole

Reference:
Pyrazole – Wikipedia,
,Pyrazoles – an overview | ScienceDirect Topics

An article Removal of methylene blue by new tunable aryl/alkyl ionic liquids/salts (TAAILs) from aqueous solution WOS:000489804300001 published article about ACTIVATED CARBON; LIQUID; EXTRACTION; EQUILIBRIUM; ADSORPTION; STABILITY; SOLVENTS; RECOVERY; SALTS; DYES in [Ozdemir, Melek Canbulat] Middle East Tech Univ, Fac Engn, Dept Environm Engn, TR-06800 Ankara, Turkey in 2020.0, Cited 54.0. SDS of cas: 67-51-6. The Name is 3,5-Dimethyl-1H-pyrazole. Through research, I have a further understanding and discovery of 67-51-6

The removal of methylene blue (MB) from aqueous solution has been investigated using new tunable 1-aryl-2-alkyl-3,5-dimethylpyrazolium hexafluorophosphate salts ([Ph(R)C(R?)pz][PF6], R: -Cl, -Br, -Me, -OMe, R?: -C2H5, or -C4H9) as an extractant and methylene chloride as a diluent. The influence of p-substituent and alkyl chain length on the removal efficiency of MB from aqueous solution was investigated. The obtained results show that MB was extracted from aqueous solution with high extraction efficiency up to 99.7 % in a very short time. The salt (4a) used for extraction of MB was recovered and reused for four runs.

Welcome to talk about 67-51-6, If you have any questions, you can contact Ozdemir, MC or send Email.. SDS of cas: 67-51-6

Reference:
Pyrazole – Wikipedia,
,Pyrazoles – an overview | ScienceDirect Topics

Category: pyrazoles-derivatives. Authors Horiuchi, S; Tanaka, S; Moon, S; Sakuda, E; Ito, A; Arikawa, Y; Umakoshi, K in AMER CHEMICAL SOC published article about in [Horiuchi, Shinnosuke; Tanaka, Seiya; Moon, Sangjoon; Sakuda, Eri; Arikawa, Yasuhiro; Umakoshi, Keisuke] Nagasaki Univ, Grad Sch Engn, Div Chem & Mat Sci, Nagasaki 8528521, Japan; [Ito, Akitaka] Kochi Univ Technol, Grad Sch Engn, Kami, Kochi 7821502, Japan in 2021.0, Cited 52.0. The Name is 3,5-Dimethyl-1H-pyrazole. Through research, I have a further understanding and discovery of 67-51-6

The synthesis and photophysical properties of the heteropolynuclear Pt-Ag complex having cyclometalated rollover bipyridine ligands (bpy*) and bridging pyrazolato ligands are reported. The Pt2Ag2 complex was synthesized by two step reactions from a Pt(II) complex precursor having the rollover bpy* ligand, [Pt(bpy*)(dmso)Cl], with 3,5-dimethylpyrazole (Me(2)pzH) and a subsequent replacement of NH protons in the Me(2)pzH moieties with the Ag(I) ion. The Pt2Ag2 complex exists as a mixture of U- and Z-shaped isomers in solution, whose structures were clearly determined by single-crystal X-ray structural analyses. NMR studies using the single crystals revealed rapid isomerization of the Pt2Ag2 complexes in solution, although the Pt2Ag2 structures were supported effectively by the multiple metal-metal interactions. Furthermore, the Pt2Ag2 framework can capture a Ag(I) ion during the U-Z isomerization to afford a Pt2Ag3 core with the formation of Pt. Ag dative bonds. The Pt2Ag3 complex showed further aggregation to form a dimer structure in the presence of coordinating solvent via the crystallization process. The formation of Pt. Ag dative bonds significantly changes the emission energy from the Pt2Ag2 complex, while the emission spectra of U- and Z-isomers of Pt2Ag2 complex almost coincide with each other and their emissive properties are very similar. The density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations revealed the effects of additional Ag(I) ion on the photophysical properties of the heteropolynuclear Pt-Ag complexes bearing the rollover bpy* ligands.

Category: pyrazoles-derivatives. Bye, fridends, I hope you can learn more about C5H8N2, If you have any questions, you can browse other blog as well. See you lster.

Reference:
Pyrazole – Wikipedia,
,Pyrazoles – an overview | ScienceDirect Topics