GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • MDPI AG  (14)
  • 1
    Online Resource
    Online Resource
    Design, Synthesis, and In Vitro and In Vivo Antifungal Activity of Novel Triazoles Containing Phenylethynyl Pyrazole Side Chains
    MDPI AG ; 2022
    In:  Molecules Vol. 27, No. 11 ( 2022-05-24), p. 3370-
    Details
    In: Molecules, MDPI AG, Vol. 27, No. 11 ( 2022-05-24), p. 3370-
    Abstract: A series of triazole derivatives containing phenylethynyl pyrazole moiety as side chain were designed, synthesized, and most of them exhibited good in vitro antifungal activities. Especially, compounds 5k and 6c showed excellent in vitro activities against C. albicans (MIC = 0.125, 0.0625 μg/mL), C. neoformans (MIC = 0.125, 0.0625 μg/mL), and A. fumigatus (MIC = 8.0, 4.0 μg/mL). Compound 6c also exerted superior activity to compound 5k and fluconazole in inhibiting hyphae growth of C. albicans and inhibiting drug-resistant strains of C. albicans, and it could reduce fungal burdens in mice kidney at a dosage of 1.0 mg/kg. An in vivo efficacy evaluation indicated that 6c could effectively protect mice models from C. albicans infection at doses of 0.5, 1.0, and 2.0 mg/kg. These results suggested that compound 6c deserves further investigation.
    Type of Medium: Online Resource
    ISSN: 1420-3049
    URL: Article
    DOI: 10.3390/molecules27113370
    Language: English
    Publisher: MDPI AG
    Publication Date: 2022
    detail.hit.zdb_id: 2008644-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Investigation on the Edge Doping Process of Nitrogen-Doped Carbon Materials by In Situ Pyrolysis Mass Spectrometry and Laser-Induced Acoustic Desorption Mass Spectrometry
    MDPI AG ; 2023
    In:  Catalysts Vol. 13, No. 5 ( 2023-04-30), p. 830-
    Details
    In: Catalysts, MDPI AG, Vol. 13, No. 5 ( 2023-04-30), p. 830-
    Abstract: Nitrogen-doped carbon materials demonstrate high performance as electrodes in fuel cells and higher oxygen reduction reactivity than traditional Pt-based electrodes. However, the formation process of nitrogen-doped carbon materials has long been a mystery. In this study, the formation mechanism of nitrogen-doped carbon materials from polyaniline (PANI) pyrolysis was studied by the combination of in situ pyrolysis vacuum ultraviolet photoionization time-of-flight mass spectrometry (Py-VUVPI-TOF MS) and substrate-enhanced, laser-induced acoustic desorption source time-of-flight mass spectrometry (SE-LIAD-TOF MS). The initial pyrolysis species, including free radicals and intermediates, were investigated via in situ Py-VUVPI-TOF MS during the temperature-programmed desorption process (within tens of microseconds). The pyrolysis residues were collected and further investigated via SE-LIAD-TOF MS, revealing the product information of the initial pyrolysis products. The results show that the edge doping of carbon materials depends on free radical reactions rather than the direct substitution of carbon atoms by nitrogen atoms. Meanwhile, pyrrole nitrogen and pyridine nitrogen are formed by the free radical cyclization reaction and the amino aromatization reaction at the initial stage of pyrolysis, while the formation of graphitic nitrogen depends on the further polymerization reaction of pyrrole nitrogen and pyridine nitrogen.
    Type of Medium: Online Resource
    ISSN: 2073-4344
    URL: Article
    DOI: 10.3390/catal13050830
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
    detail.hit.zdb_id: 2662126-5
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Exploring the Physical-World Adversarial Robustness of Vehicle Detection
    MDPI AG ; 2023
    In:  Electronics Vol. 12, No. 18 ( 2023-09-18), p. 3921-
    Details
    In: Electronics, MDPI AG, Vol. 12, No. 18 ( 2023-09-18), p. 3921-
    Abstract: Adversarial attacks can compromise the robustness of real-world detection models. However, evaluating these models under real-world conditions poses challenges due to resource-intensive experiments. Virtual simulations offer an alternative, but the absence of standardized benchmarks hampers progress. Addressing this, we propose an innovative instant-level data generation pipeline using the CARLA simulator. Through this pipeline, we establish the Discrete and Continuous Instant-level (DCI) dataset, enabling comprehensive experiments involving three detection models and three physical adversarial attacks. Our findings highlight diverse model performances under adversarial conditions. YOLO v6 demonstrates remarkable resilience, exhibiting just a marginal 6.59% average drop in average precision (AP). In contrast, the ASA attack yields a substantial 14.51% average AP reduction, twice the effect of other algorithms. We also note that static scenes yield higher recognition AP values, and outcomes remain relatively consistent across varying weather conditions. Intriguingly, our study suggests that advancements in adversarial attack algorithms may be approaching its “limitation”. In summary, our work underscores the significance of adversarial attacks in real-world contexts and introduces the DCI dataset as a versatile benchmark. Our findings provide valuable insights for enhancing the robustness of detection models and offer guidance for future research endeavors in the realm of adversarial attacks.
    Type of Medium: Online Resource
    ISSN: 2079-9292
    URL: Article
    DOI: 10.3390/electronics12183921
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
    detail.hit.zdb_id: 2662127-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Resveratrol May Reduce the Degree of Periodontitis by Regulating ERK Pathway in Gingival-Derived MSCs
    MDPI AG ; 2023
    In:  International Journal of Molecular Sciences Vol. 24, No. 14 ( 2023-07-10), p. 11294-
    Details
    In: International Journal of Molecular Sciences, MDPI AG, Vol. 24, No. 14 ( 2023-07-10), p. 11294-
    Abstract: Gingival-derived mesenchymal stem cells (GMSCs) have strong self-renewal, multilineage differentiation, and immunomodulatory properties and are expected to be applied in anti-inflammatory and tissue regeneration. However, achieving the goal of using endogenous stem cells to treat diseases and even regenerate tissues remains a challenge. Resveratrol is a natural compound with multiple biological activities that can regulate stem cell immunomodulation when acting on them. This study found that resveratrol can reduce inflammation in human gingival tissue and upregulate the stemness of GMSCs in human gingiva. In cell experiments, it was found that resveratrol can reduce the expression of TLR4, TNFα, and NFκB and activate ERK/Wnt crosstalk, thereby alleviating inflammation, promoting the proliferation and osteogenic differentiation ability of GMSCs, and enhancing their immunomodulation. These results provide a new theoretical basis for the application of resveratrol to activate endogenous stem cells in the treatment of diseases in the future.
    Type of Medium: Online Resource
    ISSN: 1422-0067
    URL: Article
    DOI: 10.3390/ijms241411294
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
    detail.hit.zdb_id: 2019364-6
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    New Insight into Phosphorus Release of Rhizosphere Soil in the Water Level Fluctuation Zone
    MDPI AG ; 2023
    In:  Sustainability Vol. 15, No. 8 ( 2023-04-13), p. 6635-
    Details
    In: Sustainability, MDPI AG, Vol. 15, No. 8 ( 2023-04-13), p. 6635-
    Abstract: Many phosphorus release experiments have been conducted in the water level fluctuation zone (WLFZ). However, the effects of rhizospheres on the risk of soil phosphorus release remain unclear. In this study, twenty-four soil samples were collected from the WLFZ of the Pengxi River, the largest tributary of the northern Three Gorges Reservoir. Physicochemical properties, phosphorus forms and phosphatase activity in rhizosphere and near-rhizosphere soils were investigated. Both the total phosphorus (TP) and water-extracted organic phosphorus (H2O-Po) contents were significantly higher in rhizosphere soils than in near-rhizosphere soils (p 〈 0.05). Enrichment rates (ER) of TP and H2O-Po were 42.4% and 180.3%, respectively. Significant increases were also found in activities of acid phosphatase, alkaline phosphatase, and phosphodiesterase in the rhizosphere, and corresponding ERs were 95.3%, 76.1%, and 22.0%, respectively. Environmental factors, such as pH, organic matter, and amorphous manganese, made significant contributions to the variations of phosphorus forms and phosphatase activities. The risk of phosphorus release to water in the rhizosphere soils of the study area increased slightly, according to the water-extracted phosphorus index. This risk may further increase due to flooding, as plant uptake of soil phosphorus would be inhibited while inorganic phosphorus is still generated by phosphatase.
    Type of Medium: Online Resource
    ISSN: 2071-1050
    URL: Article
    DOI: 10.3390/su15086635
    Language: English
    Publisher: MDPI AG
    Publication Date: 2023
    detail.hit.zdb_id: 2518383-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    How to Promote Online Education through Educational Software—An Analytical Study of Factor Analysis and Structural Equation Modeling with Chinese Users as an Example
    MDPI AG ; 2022
    In:  Systems Vol. 10, No. 4 ( 2022-07-11), p. 100-
    Details
    In: Systems, MDPI AG, Vol. 10, No. 4 ( 2022-07-11), p. 100-
    Abstract: Online learning has emerged as a fresh method to successfully prevent teacher and student gatherings as well as the propagation of viruses in the context of the ongoing influence of the COVID-19. A problem deserving of consideration is how to increase users’ desire to participate in online learning through online class APPs, identify the variables that affect users’ use of them, and create a useful assessment scale. In this study, user ratings from 68 students who had used an online class APP were collected using the combination of qualitative and quantitative research, and 200 online questionnaires were sent out to complement the interview findings, based on which 328 assessment questionnaires were gathered and 23 valid items were obtained. The influencing elements that had an impact on users’ online learning experiences were identified using factor analysis, and the relationships among the components were investigated using structural equation modeling. Perceived benefits are the main influencing factors, subjective norms and functional quality are the direct factors influencing users’ perceived benefits, and self-efficacy is influenced by subjective norms while promoting the perception of functional quality. The factors influencing users’ use of online class APPs are ultimately identified as perceived benefits, functional quality and self-efficacy. In order to facilitate users’ online learning, user psychological traits, social ties and software functions should be integrated into a cohesive system while designing online class APPs.
    Type of Medium: Online Resource
    ISSN: 2079-8954
    URL: Article
    DOI: 10.3390/systems10040100
    Language: English
    Publisher: MDPI AG
    Publication Date: 2022
    detail.hit.zdb_id: 2663185-4
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Simultaneous Optimization of Ultrasound-Assisted Extraction for Flavonoids and Antioxidant Activity of Angelica keiskei Using Response Surface Methodology (RSM)
    MDPI AG ; 2019
    In:  Molecules Vol. 24, No. 19 ( 2019-09-24), p. 3461-
    Details
    In: Molecules, MDPI AG, Vol. 24, No. 19 ( 2019-09-24), p. 3461-
    Abstract: Angelica keiskei Koidzumi (A. keiskei), as a Japanese edible herbal plant, enjoys a variety of biological activities due to the presence of numerous active compounds, especially flavonoids. This study aims for the optimization of ultrasound-assisted extraction (UAE) for flavonoids in A. keiskei and their antioxidant activity by using the response surface methodology (RSM). Single-factor experiments and a four-factor three-level Box–Behnken design (BBD) were performed to explore the effects of the following parameters on flavonoid extraction and antioxidant activity evaluation: ultrasonic temperature (X1), ultrasonic time (X2), ethanol concentration (X3) and liquid–solid ratio (X4). The optimum conditions of the combination of total flavonoid content (TFC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity (DPPH-RSC) and ferric-reducing antioxidant power (FRAP) were as follows: X1 = 80 °C, X2 = 4 min, X3 = 78%, X4 = 35 mL/g, respectively. The experimental results provide a theoretical basis for the extensive utilization of A. keiskei and flavonoids extraction from A. keiskei as a potential source of antioxidants.
    Type of Medium: Online Resource
    ISSN: 1420-3049
    URL: Article
    DOI: 10.3390/molecules24193461
    Language: English
    Publisher: MDPI AG
    Publication Date: 2019
    detail.hit.zdb_id: 2008644-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Modulation of Thermal Insulation and Mechanical Property of Silica Aerogel Thermal Insulation Coatings
    MDPI AG ; 2022
    In:  Coatings Vol. 12, No. 10 ( 2022-09-28), p. 1421-
    Details
    In: Coatings, MDPI AG, Vol. 12, No. 10 ( 2022-09-28), p. 1421-
    Abstract: In this paper, high-performance silica aerogel (SiO2 aerogel) thermal insulation coatings were obtained and profited from the excellent thermal insulation capability of SiO2 aerogel. The comprehensive properties and thermal insulation mechanism of the coatings were investigated via Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), contact angle, and temperature difference tests. Results showed that there was a contradiction between thermal insulation and mechanical property in this coating after the addition amount and proportion of silica aerogel, hollow glass microsphere, glass fibers, aqueous acrylic emulsion, and dispersing agents were optimized carefully. When the mass ratio of hollow glass to SiO2 aerogel microspheres was 1:1, the overall performance of the coating was the best with thermal conductivity of 0.050 W/(m·K) and adhesive strength of 1024 kPa.
    Type of Medium: Online Resource
    ISSN: 2079-6412
    URL: Article
    DOI: 10.3390/coatings12101421
    Language: English
    Publisher: MDPI AG
    Publication Date: 2022
    detail.hit.zdb_id: 2662314-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    4-Hydroxyderricin Promotes Apoptosis and Cell Cycle Arrest through Regulating PI3K/AKT/mTOR Pathway in Hepatocellular Cells
    MDPI AG ; 2021
    In:  Foods Vol. 10, No. 9 ( 2021-08-29), p. 2036-
    Details
    In: Foods, MDPI AG, Vol. 10, No. 9 ( 2021-08-29), p. 2036-
    Abstract: 4-hydroxyderricin (4-HD), as a natural flavonoid compound derived from Angelica keiskei, has largely unknown inhibition and mechanisms on liver cancer. Herein, we investigated the inhibitory effects of 4-HD on hepatocellular carcinoma (HCC) cells and clarified the potential mechanisms by exploring apoptosis and cell cycle arrest mediated via the PI3K/AKT/mTOR signaling pathway. Our results show that 4-HD treatment dramatically decreased the survival rate and activities of HepG2 and Huh7 cells. The protein expressions of apoptosis-related genes significantly increased, while those related to the cell cycle were decreased by 4-HD. 4-HD also down-regulated PI3K, p-PI3K, p-AKT, and p-mTOR protein expression. Moreover, PI3K inhibitor (LY294002) enhanced the promoting effect of 4-HD on apoptosis and cell cycle arrest in HCC cells. Consequently, we demonstrate that 4-HD can suppress the proliferation of HCC cells by promoting the PI3K/AKT/mTOR signaling pathway mediated apoptosis and cell cycle arrest.
    Type of Medium: Online Resource
    ISSN: 2304-8158
    URL: Article
    DOI: 10.3390/foods10092036
    Language: English
    Publisher: MDPI AG
    Publication Date: 2021
    detail.hit.zdb_id: 2704223-6
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    Pairwise Registration Algorithm for Large-Scale Planar Point Cloud Used in Flatness Measurement
    MDPI AG ; 2021
    In:  Sensors Vol. 21, No. 14 ( 2021-07-16), p. 4860-
    Details
    In: Sensors, MDPI AG, Vol. 21, No. 14 ( 2021-07-16), p. 4860-
    Abstract: In this paper, an optimized three-dimensional (3D) pairwise point cloud registration algorithm is proposed, which is used for flatness measurement based on a laser profilometer. The objective is to achieve a fast and accurate six-degrees-of-freedom (6-DoF) pose estimation of a large-scale planar point cloud to ensure that the flatness measurement is precise. To that end, the proposed algorithm extracts the boundary of the point cloud to obtain more effective feature descriptors of the keypoints. Then, it eliminates the invalid keypoints by neighborhood evaluation to obtain the initial matching point pairs. Thereafter, clustering combined with the geometric consistency constraints of correspondences is conducted to realize coarse registration. Finally, the iterative closest point (ICP) algorithm is used to complete fine registration based on the boundary point cloud. The experimental results demonstrate that the proposed algorithm is superior to the current algorithms in terms of boundary extraction and registration performance.
    Type of Medium: Online Resource
    ISSN: 1424-8220
    URL: Article
    DOI: 10.3390/s21144860
    Language: English
    Publisher: MDPI AG
    Publication Date: 2021
    detail.hit.zdb_id: 2052857-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...