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1.
Plant Physiol ; 184(2): 923-932, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32796091

RESUMEN

Photoperiod- and thermosensitive genic male sterility (P/TGMS) lines are widely used in crop breeding. The fertility conversion of Arabidopsis (Arabidopsis thaliana) TGMS lines including cals5-2, which is defective in callose wall formation, relies on slow development under low temperatures. In this study, we discovered that cals5-2 also exhibits PGMS. Fertility of cals5-2 was restored when pollen development was slowed under short-day photoperiods or low light intensity, suggesting that slow development restores the fertility of cals5-2 under these conditions. We found that several other TGMS lines with defects in pollen wall formation also exhibited PGMS characteristics. This similarity indicates that slow development is a general mechanism of PGMS fertility restoration. Notably, slow development also underlies the fertility recovery of TGMS lines. Further analysis revealed the pollen wall features during the formation of functional pollens of these P/TGMS lines under permissive conditions. We conclude that slow development is a general mechanism for fertility restoration of P/TGMS lines and allows these plants to take different strategies to overcome pollen formation defects.


Asunto(s)
Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , Fotoperiodo , Infertilidad Vegetal/genética , Infertilidad Vegetal/fisiología , Polen/crecimiento & desarrollo , Polen/genética , Frío , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Variación Genética , Genotipo
2.
J Appl Toxicol ; 41(11): 1826-1838, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33759202

RESUMEN

2-isopropyl-N,2,3-trimethylbutyramide (WS-23) is a well-known artificial synthesis cooling agent widely used in foods, medicines, and tobaccos. As a commonly cooling agent in e-cigarette liquids, WS-23 has led to concerns about the inhalation toxicity with the prosperous of e-cigarettes in recent years. Thus, the aim of this study is to assess the acute and subacute inhalation toxicity of WS-23 in Sprague-Dawley (SD) rats according to the Organization for Economic Cooperation and Development (OECD) guidelines. In the acute toxicity study, there was no mortality and behavioral signs of toxicity at the limit test dose level (340.0 mg/m3 ) in the exposure period and the following 14-day observation period. In the subacute inhalation toxicity study, there was no significant difference observed in the body weights, feed consumption, and relative organ weights. Haematological, serum biochemical, urine, and bronchoalveolar lavage fluid (BALF) analysis revealed the non-adverse effects after 28-day repeated WS-23 inhalation (342.85 mg/m3 ), accompanied by slight changes in few parameters which returned to normal during the 28-day recovery period. The histopathologic examination also did not show any differences in vital organs. In conclusion, the maximum tolerated dose for WS-23 acute inhalation is not less than 340.0 mg/m3 , and the No Observed Adverse Effect Level (NOAEL) of WS-23 subacute inhalation was determined to be over 342.85 mg/m3 .


Asunto(s)
Amidas/toxicidad , Exposición por Inhalación , Animales , Femenino , Masculino , Ratas , Ratas Sprague-Dawley , Organismos Libres de Patógenos Específicos , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Subaguda
3.
Chemistry ; 26(45): 10307-10313, 2020 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-32363612

RESUMEN

Recently, 2D organic-inorganic hybrid lead halide perovskites have attracted intensive attention in solid-state luminescence fields such as single-component white-light emitters, and rational optimization of the photoluminescence (PL) performance through accurate structural-design strategies is still significant. Herein, by carefully choosing homologous aliphatic amines as templates, isotypical perovskites [DMEDA]PbCl4 (1, DMEDA=N,N-dimethylethylenediamine) and [DMPDA]PbCl4 (2, DMPDA=N,N-dimethyl-1,3-diaminopropane) having tunable and stable broadband bluish white emission properties were rationally designed. The subtle regulation of organic cations leads to a higher degree of distortion of the 2D [PbCl4 ]2- layers and enhanced photoluminescence quantum efficiencies (<1 % for 1 and 4.9 % for 2). The broadband light emissions could be ascribed to self-trapped excitons on the basis of structural characterization, time-resolved PL, temperature-dependent PL emission, and theoretical calculations. This work gives a new guidance to rationally optimize the PL properties of low-dimensional halide perovskites and affords a platform to probe the structure-property relationship.

4.
Inorg Chem ; 59(19): 14085-14092, 2020 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-32926625

RESUMEN

In recent years, two-dimensional (2D) hybrid lead halide perovskites based on corner-shared [PbX6] octahedrons have received extensive attention with important potentials in single-component white-light emitting diodes (WLEDs) due to the soft and distorted crystal lattices. However, limited research focused on the one-dimensional (1D) perovskites although they possess similar structural superiorities to achieve this performance. Herein, by using different types of organic amine cations as structural direction reagents, we report one new type of hybrid 1D perovskites of APbCl3 (A = (DTHPE)0.5, DMTHP, DBN) based on the same 1D face-shared octahedral [PbCl3]- chains. Upon UV light excitation, these 1D APbCl3 perovskites exhibit intrinsic broad-band bluish white-light emissions covering entire visible light spectra with the highest photoluminescence quantum yield (PLQY) of 6.99%, which catches up with the values of previously reported 2D perovskites. Through the systematical studies of time-resolved, temperature-dependent PL emissions, theoretical calculations, and so on, these broad-band light emissions can be ascribed to the radiative transition within conjugated organic cations. The facile assembly process, intrinsic broad-band light emissions, and high PLQYs enable these 1D APbCl3 perovskites as new types of promising candidates in fabricating single-component WLEDs.

5.
Bioorg Chem ; 104: 104258, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32956876

RESUMEN

Five new nitrogen-containing compounds (1-3, 5, and 6), two compounds which was firstly isolated from natural origin (7 and 10), along with six known ones, were isolated from the ethanol extract of the whole bodies of Polyphaga plancyi. The structures of the new compounds including their absolute configurations at stereogenic centers were assigned on the basis of spectroscopic analyses and computational methods. Racemic 10 was separated by chiral HPLC. Biological activities of these isolates against extracellular matrix components in rat renal proximal tubular cells, EV71, COX-2, ROCK2, JAK3, and tuberculosis were evaluated. Importantly, 8 was found to be a selective Smad3 phosphorylation inhibitor.


Asunto(s)
Antituberculosos/farmacología , Productos Biológicos/farmacología , Escarabajos/química , Ciclooxigenasa 2/metabolismo , Inhibidores Enzimáticos/farmacología , Janus Quinasa 3/antagonistas & inhibidores , Tuberculosis/tratamiento farmacológico , Animales , Antituberculosos/química , Antituberculosos/aislamiento & purificación , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Células Cultivadas , Teoría Funcional de la Densidad , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Janus Quinasa 3/metabolismo , Estructura Molecular , Ratas , Relación Estructura-Actividad
6.
Bioorg Chem ; 102: 104086, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32688114

RESUMEN

Pipajiains H-J (1-3), three new phenolic derivatives with an unusual sulfone group, pipajiamides A-C (4-6), three new amide derivatives, pipajiaine A (7), one new imidazole analogue, and pipajiaine B (8), a pair of new pyrrolidine derivatives, along with three known compounds were isolated from the insect Blaps japanensis. Their structures were identified by spectroscopic and computational methods. Chiral HPLC was used to separate the (-)- and (+)-antipodes of 4 and 8. Biological activities of all the new compounds against extracellular matrix in rat renal proximal tubular cells, human cancer cells (A549, Huh-7, and K562), COX-2, ROCK1, and JAK3 were evaluated. The results show that compounds 2, (+)-4, and (-)-4 are active against kidney fibrosis, whereas, compound 9 is active toward human cancer cells, inflammation, and JAK3 kinase.


Asunto(s)
Escarabajos/química , Compuestos de Nitrógeno/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Azufre/farmacología , Animales , Células Cultivadas , Teoría Funcional de la Densidad , Relación Dosis-Respuesta a Droga , Fibrosis/tratamiento farmacológico , Humanos , Janus Quinasa 3/antagonistas & inhibidores , Janus Quinasa 3/metabolismo , Estructura Molecular , Compuestos de Nitrógeno/química , Compuestos de Nitrógeno/aislamiento & purificación , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/aislamiento & purificación , Ratas , Relación Estructura-Actividad , Azufre/química , Azufre/aislamiento & purificación , Quinasas Asociadas a rho/antagonistas & inhibidores , Quinasas Asociadas a rho/metabolismo
7.
J Environ Manage ; 248: 109280, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31326726

RESUMEN

Robustness and cost effectiveness are major concerns for sustainable stormwater management under deep uncertainty of climate change. Given that many traditional static planning strategies are not working with unpredictable future conditions, the possibility of system failure, and the lock-in effects, the Adaptation Pathway (AP) approach was adopted for dynamically robust and cost-effective planning in this paper. In order to increase optimization accuracy of multi-staged planning, a continuous definition of the AP optimization problem was raised by improving the simplified versions in existing studies. A case study in Suzhou, a provincial pilot Sponge City in China undergoing increasing annual rainfall and severe water environment deterioration, was included by integrating Long-Term Hydrologic Impact Assessment-Low Impact Development model with optimization methods, aiming to persistently control the non-point source total phosphorus loading below an acceptable amount in the following unforeseen 20 years via multi-staged low-impact development (LID) construction. A novel optimization method developed by the authors in a companion paper, namely marginal-cost-based greedy strategy (MCGS), was successfully applied to efficiently solve the continuous version of the AP optimization problem. The popular genetic algorithm (GA) was used as a contrast. A weather generator was elaborated based on four Representative Concentration Pathway scenarios and 17 spatial downscaled general circulation models to simulate the unforeseen future annual rainfalls that helped with evaluating cost effectiveness of each prospective LID plan. Results showed that the adaptation pathways optimized by MCGS could save the whole life net present cost of an LID plan by 1%-60% compared with those optimized by GA, and the computational efficiency of MCGS was over 13 times faster than GA.


Asunto(s)
Cambio Climático , Planificación Social , China , Ciudades , Estudios Prospectivos , Incertidumbre
8.
Photosynth Res ; 126(2-3): 311-21, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26123918

RESUMEN

After transcription, most chloroplast precursor RNAs undergo further post-transcriptional processing including cleavage, editing, and splicing. Previous investigation has shown that the cleavage of the rpoA transcript and most editing sites, including accD-1, are defective in the knockout mutant of PDM1/SEL1, a PLS-type PPR protein, and that PDM1 is associated with the rpoA transcript. In this work, we found that the splicing of group II introns in trnK and ndhA is also affected in pdm1. Co-immunoprecipitation mass spectrometry experiments were performed to identify proteins that are associated with PDM1. We obtained 126 non-redundant proteins, of which MORF9 was reported to be involved in RNA editing in chloroplast. Yeast two-hybrid assays showed that PDM1 interacts directly with MORF9, MORF2, and MORF8. RNA immunoprecipitation showed that PDM1 associates with the transcripts of trnK and ndhA, as well as accD-1, suggesting that PDM1 is involved in RNA editing and splicing. Therefore, PDM1 is an important protein for post-transcriptional regulation in chloroplast.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas de Cloroplastos/metabolismo , Procesamiento Proteico-Postraduccional , Especies Reactivas de Oxígeno/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Cloroplastos/genética , Modelos Biológicos , Plastidios/genética , Edición de ARN , Empalme del ARN , ARN de Planta/genética
9.
Front Pharmacol ; 14: 1254236, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37781700

RESUMEN

Bladder cancer (BC) is a common form of urinary tract tumor, and its incidence is increasing annually. Unfortunately, an increasing number of newly diagnosed BC patients are found to have advanced or metastatic BC. Although current treatment options for BC are diverse and standardized, it is still challenging to achieve ideal curative results. However, Sulforaphane, an isothiocyanate present in cruciferous plants, has emerged as a promising anticancer agent that has shown significant efficacy against various cancers, including bladder cancer. Recent studies have demonstrated that Sulforaphane not only induces apoptosis and cell cycle arrest in BC cells, but also inhibits the growth, invasion, and metastasis of BC cells. Additionally, it can inhibit BC gluconeogenesis and demonstrate definite effects when combined with chemotherapeutic drugs/carcinogens. Sulforaphane has also been found to exert anticancer activity and inhibit bladder cancer stem cells by mediating multiple pathways in BC, including phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR), mitogen-activated protein kinase (MAPK), nuclear factor kappa-B (NF-κB), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), zonula occludens-1 (ZO-1)/beta-catenin (ß-Catenin), miR-124/cytokines interleukin-6 receptor (IL-6R)/transcription 3 (STAT3). This article provides a comprehensive review of the current evidence and molecular mechanisms of Sulforaphane against BC. Furthermore, we explore the effects of Sulforaphane on potential risk factors for BC, such as bladder outlet obstruction, and investigate the possible targets of Sulforaphane against BC using network pharmacological analysis. This review is expected to provide a new theoretical basis for future research and the development of new drugs to treat BC.

10.
Drug Test Anal ; 15(10): 1156-1163, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35712913

RESUMEN

Use of electronic cigarettes (e-cigarettes) has increased significantly over the past decade due to consumer perception that these products represent a less risky alternative to combustible cigarettes. E-liquids generally contain a simple mix of vegetable glycerin, propylene glycerol, nicotine, organic acids, and flavourings. Regulators require that harmful and potentially harmful constituents (HPHCs) that might cause harm to the consumer must be monitored in the aerosol generated by e-cigarettes and in cigarette smoke (CS). To quantify HPHCs in aerosols from commercial flavoured e-cigarettes in Chinese market, this study has systematically compared levels of HPHCs, including eight carbonyls, five volatile organic compounds, four tobacco-specific nitrosamines, 16 polycyclic aromatic hydrocarbons, and seven heavy metals, in the aerosols of four market-leading flavoured e-cigarettes and mainstream CS, alongside in vitro cytotoxicity and mutagenicity assays. The vast majority of HPHCs were either undetected or significantly lower in the e-cigarette aerosols than in commercial CS or reference CS (3R4F). Where HPHCs were detected, there were small variations among the different flavoured e-cigarettes. In the neutral red uptake and Ames assays, aqueous extracts of the e-cigarette aerosols did not induce obvious cytotoxicity or mutagenicity, whereas CS aqueous extract showed dose-related cytotoxicity and mutagenicity. Collectively, these results indicate that use of e-cigarettes might potentially lead to a significant reduction in exposure to harmful substances, with fewer cytotoxic and mutagenic effects, as compared with conventional smoking. Further studies based on human puffing conditions and longer evaluation periods will be needed to substantiate this potential.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Productos de Tabaco , Humanos , Productos de Tabaco/análisis , Nicotina/análisis , Aerosoles/toxicidad , Nicotiana
11.
Ann Transl Med ; 10(20): 1109, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36388786

RESUMEN

Background: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a serious threat to health, and the detection rate in intensive care units (ICUs) is relatively high. We compared regional differences in the clinical and molecular characteristics of CRKP from three ICUs in different hospitals, to make a reference and contribution for infection control and clinical medication. Methods: A total of 150 CRKP strains from Chongqing, Beijing, and Nantong, as well as the clinical data of the infected patients, were collected between 2019 and 2021. The carbapenemase phenotype was determined by CarbaNP test, and the outer membrane porin (OMP) genes (ompK35/ompK36), multi-locus sequence typing (MLST) and resistance genes were identified by polymerase chain reaction (PCR) amplification and sequencing. Results: Patients infected with CRKP were mainly elderly, with comorbidity, and had undergone invasive operation and multiple antibiotic therapy. All strains exhibited high-level resistance to most antibiotics except for polymyxin B and tigecycline. Among the CRKP strains, 100 had the bla KPC-2 gene and 8 had bla NDM-1 gene, which were distributed in all of the hospitals. Nearly all the strains harbored extended-spectrum beta-lactamase (ESBL) genes (bla SHV, bla CTX-M, and bla TEM). Class C carbapenemase genes (bla CIT, bla DHA), and deletion and mutation of ompK35/ompK36 existed in some strains. ST11 was the main MLST type, followed by ST15. Conclusions: There were a few significant differences in the molecular epidemiology and clinical characteristics, but generally the features of CRKP from the three ICUs aligned fairly well, which might have resulted from dissemination through frequent personnel exchanges between regions.

12.
Phytochemistry ; 199: 113184, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35405148

RESUMEN

Five undescribed benzopyran containing meroterpenoids, ganodercins Q-U, two undescribed benzofuran containing meroterpenoids, ganodercins V and W, and two known meroterpenoids were isolated from Ganoderma cochlear. Their structures were elucidated by using HRESIMS, NMR spectroscopy and computational methods. The results of biochemical studies using a palmitic acid (PA) induced insulin resistance (IR) model show that (-)-ganodercin Q, (+)-ganodercins R and W activate phospho-AKT (p-AKT) at 20 µM and improve glucose uptake in a concentration dependent manner. The results of renoprotection studies show that (+)-ganodercin S, cochlearol F, (+)- and (-)-ganodercins V reduce the expression of collagen I.


Asunto(s)
Benzofuranos , Ganoderma , Benzofuranos/farmacología , Benzopiranos , Ganoderma/química , Estructura Molecular , Proteínas Proto-Oncogénicas c-akt , Terpenos/química , Terpenos/farmacología
13.
Environ Pollut ; 296: 118743, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34953955

RESUMEN

Algal blooms in urban water system is an international concern, which especially in China, have become a major obstacle to the urban water environment improvement since the preliminary achievements were made in the treatment of black and odorous water bodies. The complex blooming mechanisms require a joint regulation plan. This study established a framework that consisted of three steps, i.e., simulation, optimization, and verification, to build an optimal joint regulation plan. By taking the urban river network in Suzhou Pingjiang Xincheng as a case study, the cost-benefits of six alternative regulation measures were assessed using an algal bloom mechanism model and the discounted cash flow model based on 70 regulation scenarios. The joint regulation plan was optimized using the marginal-cost-based greedy strategy on the basis of the cost-benefits of different measures. The optimized joint plans, which were verified to be global optima, were more cost-effective than the designed regulation scenarios, and reduced the average chlorophyll-a concentrations by 55.3%-60.1% compared with the status quo. Applying the optimized cost allocation ratios of each measure to adjust the existing regulation scheme of another similar case verified that the optimization results had great generalizability.


Asunto(s)
Fósforo , Agua , China , Análisis Costo-Beneficio , Monitoreo del Ambiente , Eutrofización , Fósforo/análisis
14.
Nat Prod Bioprospect ; 11(1): 51-62, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32876846

RESUMEN

Ten neolignans or norlignans (1-10) including eight new compounds were isolated from the whole bodies of Polyphaga plancyi Bolivar. Their structures were identified by spectroscopic data. Compounds 3, 4, 8, and 9 are racemates indicated by chiral HPLC analysis. Chiral separation followed by ECD calculations allowed to clarify the absolute configurations of all the antipodes. All the new compounds were evaluated for their biological properties toward extracellular matrix in rat renal proximal tubular cells, human cancer cells (K562, A549, and Huh7), EV71, ROCK2, JAK3, DDR1, and coagulation.

15.
Sci Total Environ ; 753: 141821, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-32891993

RESUMEN

Intense human disturbance has made algal bloom a prominent environmental problem in gate-controlled urban water bodies. Urban water bodies present the characteristics of natural rivers and lakes simultaneously, whose algal blooms may manifest multi-factor interactions. Hence, effective regulation strategies require a multi-factor analysis to understand local blooming mechanisms. This study designed a holistic multi-factor analysis framework by integrating five data mining techniques. First, the Kolmogorov-Smirnov test was conducted to screen out the possible explanatory variables. Then, correlation analyses and principal component analyses were performed to identify variable collinearity and mutual causality, respectively. After collinearity and mutual causality were treated prudently by using orthogonalization and instrumental variables, multilinear regression can be properly conducted to quantify factor contributions to algae growth. Lastly, a decision tree was used innovatively to depict the limiting threshold curves of each driving factor that restricts algae growth under different circumstances. The driving factors, their contributions, and the limiting threshold curves compose the complete blooming mechanisms, thus providing a clear direction for the targeted regulation task. A typical case study was performed in Suzhou, a Chinese city with an intricate gate-controlled river network. Results confirmed that climatic factors (i.e., water temperature and solar radiation), hydrodynamic factors (i.e., flow velocity), nutrients (i.e., phosphorus and nitrogen), and external loadings contributed 49.3%, 21.7%, 21.3%, and 7.7%, respectively, to algae growth. These results indicate that a joint regulation strategy is urgently required. Future studies can focus on coupling the revealed mechanisms with an ecological model to provide a comprehensive toolkit for the optimization of an adaptive joint regulation plan under the background of global warming.


Asunto(s)
Monitoreo del Ambiente , Eutrofización , China , Ciudades , Minería de Datos , Análisis Factorial , Humanos , Lagos , Fósforo/análisis
16.
Front Chem ; 9: 783705, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34926404

RESUMEN

Eleven new cyclohexane-type meroterpenoids (1, 3-5, 7, 8, 11-15) and four known similar meroterpenoids (2, 6, 9, and 10) were isolated from Ganoderma cochlear. Their structures and absolute configurations at stereogenic centers were elucidated by using HRESIMS, NMR spectroscopy and computational methods. In addition, the structure of the known meroterpenoid, cochlearol G (2), was revised, and the absolute configurations at the stereogenic centers of known meroterpenoids 9 and 10 were determined. All the isolated meroterpenoids were evaluated for their activities against renal fibrosis and triple negative breast cancer, and their insulin resistance. The results of the renal fibrosis study showed that meroterpenoid 11 inhibits over-expression of fibronectin, collagen I and α-SMA. Results of the wound healing study revealed that 4, 6 and 8 significantly inhibit migration of BT549 cells. Observations made in Western blotting experiments showed that 6 decreases the levels of TWIST1 and ZEB1, and increases the level of E-cadherin. Finally, meroterpenoids 7, 9, 11, and 15 significantly up-regulate p-AMPK protein expression in normal L6 myotubes cells.

17.
Sci Total Environ ; 728: 138608, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32570310

RESUMEN

In recent years, Sponge City has gained significant interests as a way of urban water management. The kernel of Sponge City is to develop a coupled green-grey-blue system which consists of green infrastructure at the source, grey infrastructure (i.e. drainage system) at the midway and receiving water bodies as the blue part at the terminal. However, the current approaches for assessing the performance of Sponge City construction are confined to green-grey systems and do not adequately reflect the effectiveness in runoff reduction and the impacts on receiving water bodies. This paper proposes an integrated assessment framework of coupled green-grey-blue systems on compliance of water quantity and quality control targets in Sponge City construction. Rainfall runoff and river system models are coupled to provide quantitative simulation evaluations of a number of indicators of land-based and river quality. A multi-criteria decision-making method, i.e., Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) is adopted to rank design alternatives and identify the optimal alternative for Sponge City construction. The effectiveness of this framework is demonstrated in a typical plain river network area of Suzhou, China. The results demonstrate that the performance of Sponge City strategies increases with large scale deployment under smaller rainfall events. In addition, though surface runoff has a dilution effect on the river water quality, the control of surface pollutants can play a significant role in the river water quality improvement. This framework can be applied to Sponge City projects to achieve the enhancement of urban water management.

18.
Org Lett ; 22(15): 5726-5730, 2020 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-32525688

RESUMEN

Aspongdopamines A and B (1 and 2), unusual adducts composed of N-acetyldopamine and adenine were isolated from the insect Aspongopus chinensis. Compounds 1 and 2 are positional isomers both isolated as racemates. Chiral separation assisted by 14-step total synthesis and computation including vibrational circular dichroism calculations allowed us to unambiguously assign the absolute configurations of eight stereoisomers. Renal fibrosis inhibition of the stereoisomers was evaluated in TGF-ß1-induced rat kidney epithelial cells.


Asunto(s)
Adenina/síntesis química , Productos Biológicos/farmacología , Dopamina/análogos & derivados , Insectos/efectos de los fármacos , Factor de Crecimiento Transformador beta1/química , Adenina/química , Animales , Dicroismo Circular , Dopamina/síntesis química , Dopamina/química , Estructura Molecular , Ratas , Estereoisomerismo , Factor de Crecimiento Transformador beta1/metabolismo
19.
Nat Plants ; 6(4): 360-367, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32231254

RESUMEN

Temperature-sensitive genic male sterility (TGMS) lines are widely used in the breeding of hybrid crops1,2, but by what means temperature as a general environmental factor reverses the fertility of different TGMS lines remains unknown. Here, we identified an Arabidopsis TGMS line named reversible male sterile (rvms) that is fertile at low temperature (17 °C) and encodes a GDSL lipase. Cytological observations and statistical analysis showed that low temperature slows pollen development. Further screening of restorers of rvms, as well as crossing with a slow-growth line at normal temperature (24 °C), demonstrate that slowing of development overcomes the defects of rvms microspores and allows them to develop into functional pollen. Several other Arabidopsis TGMS lines were identified, and their fertility was also restored by slowing of development. Given that male reproductive development is conserved3, we propose that slowing of development is a general mechanism applicable to the sterility-fertility conversion of TGMS lines from different plant species.


Asunto(s)
Arabidopsis/fisiología , Termotolerancia , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/ultraestructura , Frío , Fertilidad/genética , Perfilación de la Expresión Génica , Interacción Gen-Ambiente , Genes de Plantas , Mutación , Desarrollo de la Planta/genética , Desarrollo de la Planta/fisiología , Polen/genética , Polen/crecimiento & desarrollo , Termotolerancia/genética
20.
J Safety Res ; 69: 177-192, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31235228

RESUMEN

INTRODUCTION: The adaptive cruise control (ACC) and cooperative ACC (CACC) systems are critical parts of self-driving vehicles. The ACC vehicles detect front vehicle' information via vehicle-mounted sensors and make longitudinal reactions automatically, while CACC vehicles enhance the performance by vehicle-to-vehicle (V2V) wireless communication. However, CACC vehicles may abruptly degrade to ACC mode in reality due to various reasons, including communication failures, driver manipulations, and cyber-attacks. The sudden degradation will definitely bring negative influences on safety. METHOD: This study quantitatively evaluated the longitudinal safety impacts of vehicles' degradation in a CACC fleet based on microscopic simulations. The realistic CACC and ACC models proposed by the California Partners for Advanced Transit and Highways (PATH) were used for simulation experiments. The time integrated time-to-collision (TIT) was measured to quantify the collision risks. Extensive simulations were conducted via a fleet of 10 CACC vehicles and speed profiles of vehicles in different scenarios were compared. Key factors, including the leading vehicle's deceleration rate, the number of vehicles between degraded vehicles (NVDVs), threshold of TTC, and visibility were also examined via sensitivity analyses. RESULTS AND CONCLUSIONS: Simulation results indicate that degradation has significant negative influences on longitudinal safety of degraded vehicles under the driving state of deceleration. Degradation at middle positions in a CACC fleet, such as fourth and fifth positions, is much safer than that at others. Moreover, nonadjacent degradation is much riskier than adjacent degradation at the front positions of a fleet. NVDVs can bring inverse impacts on safety with different degradation positions. Speed profiles imply that the hysteresis of degraded vehicles' speed control is the major reason for high collision risks. Practical applications: Appropriately, hierarchical countermeasures have the potential to reduce the longitudinal safety impacts of degradation. Findings of this study can contribute to determining the applicable length of CACC fleets.


Asunto(s)
Accidentes de Tránsito/prevención & control , Conducción de Automóvil/estadística & datos numéricos , Desaceleración/efectos adversos , Accidentes de Tránsito/estadística & datos numéricos , Estudios de Evaluación como Asunto , Humanos , Estudios Longitudinales , Equipos de Seguridad , Análisis y Desempeño de Tareas
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