171 research outputs found
Vertical Vibration Response of Footbridges with Fundamental Natural Frequency up to 10 Hz under Dynamic Loading by Single Pedestrian
This is the final version. Available on open access from ASCE via the DOI in this recordData Availability Statement:
Some or all data, models, or code that support the findings of this study as well as simulation results (Matlab) used in sections “Sensitivity analysis” and “Design spectrum” are available from the corresponding author upon reasonable request.A design spectrum of characteristic acceleration response to pedestrian-induced dynamic loading has been developed for footbridge structures. The novelty of the proposed spectrum over the existing spectra is that: (1) it is underpinned by a recently developed comprehensive statistical model of pedestrian dynamic loading; (2) it is applicable to a broader natural frequency range of structures up to 10 Hz; and (3) it accounts for uncertainties in both dynamic loading and structure dynamics that are typically encountered in structural design. In addition, the importance of correct modeling of pedestrian's walking speed and narrow-band nature of the force signal has been demonstrated. Comparison with the design spectra recommended in contemporary design codes reveals that the existing approaches are not being applicable for structures with natural frequency in the range of third, fourth, and fifth harmonic of the dynamic force. In addition, they could both underestimate and overestimate the structural response for lower-frequency structures. The proposed design spectrum is a design tool applicable to structures whose mode shape can be approximated by half-sine, span length between 12.5 and 100 m, and damping ratio between 0.25% and 2%.Spanish Ministry of Economy and Competitiveness (MINECO
A gliclazide complex based on palladium towards Alzheimer's disease: promising protective activity against Aβ-induced toxicity in C. elegans
A new palladium coordination compound based on gliclazide with
the chemical formula [Pd(glz)2] (where glz = gliclazide) has been
synthesized and characterised. The structural characterization
reveals that this material consists of mononuclear units formed by
a Pd2+ ion coordinated to two molecules of the glz ligand, in which
palladium ions exhibit a distorted plane-square coordination
sphere. This novel material behaves like a good and selective
inhibitor of butyrylcholinesterase, one of the most relevant therapeutic targets against Alzheimer’s disease. Analysis of the enzyme
kinetics showed a mixed mode of inhibition, the title compound
being capable of interacting with both the free enzyme and the
enzyme–substrate complex. Finally, the palladium compound
shows promising protective activity against Ab-induced toxicity in
the Caenorhabditis elegans model, which has never been reported
Resistin Regulates Pituitary Lipid Metabolism and Inflammation In Vivo and In Vitro
The adipokine resistin is an insulin-antagonizing factor that also plays a regulatory role in inflammation, immunity, food intake, and gonadal function and also regulates growth hormone (GH) secretion in rat adenopituitary cells cultures with the adipokine. Although adipose tissue is the primary source of resistin, it is also expressed in other tissues, including the pituitary. The aim of this study is to investigate the possible action of resistin on the lipid metabolism in the pituitary gland in vivo (rats in two different nutritional status, fed and fast, treated with resistin on acute and a chronic way) and in vitro (adenopituitary cell cultures treated with the adipokine). Here, by a combination of in vivo and in vitro experimental models, we demonstrated that central acute and chronic administration of resistin enhance mRNA levels of the lipid metabolic enzymes which participated on lipolysis and moreover inhibiting mRNA levels of the lipid metabolic enzymes involved in lipogenesis. Taken together, our results demonstrate for the first time that resistin has a regulatory role on lipid metabolism in the pituitary gland providing a novel insight in relation to the mechanism by which this adipokine can participate in the integrated control of lipid metabolism.Sara Borrell Postdoctoral program; BFU 2011 and CIBER Obesidad y Nutricion (Instituto de Salud Carlos Tercero (ISCIII), Ministerio de Ciencia e Innovacion). Juan de la Cierva Program (Ministerio de Educacion y Ciencia)S
Evolutionary feature selection to estimate forest stand variablesusing LiDAR
Light detection and ranging (LiDAR) has become an important tool in forestry. LiDAR-derived models are mostly developed by means of multiple linear regression (MLR) after stepwise selection of predictors. An increasing interest in machine learning and evolutionary computation has recently arisen to improve regression use in LiDAR data processing. Although evolutionary machine learning has already proven to be suitable for regression, evolutionary computation may also be applied to improve parametric models such as MLR. This paper provides a hybrid approach based on joint use of MLR and a novel genetic algorithm for the estimation of the main forest stand variables. We show a comparison between our genetic approach and other common methods of selecting predictors. The results obtained from several LiDAR datasets with different pulse densities in two areas of the Iberian Peninsula indicate that genetic algorithms perform better than the other methods statistically. Preliminary studies suggest that a lack of parametric conditions in field data and possible misuse of parametric tests may be the main reasons for the better performance of the genetic algorithm. This research confirms the findings of previous studies that outline the importance of evolutionary computation in the context of LiDAR analisys of forest data, especially when the size of fieldwork datatasets is reduced.Ministerio de Ciencia y Tecnología TIN2007- 68084-C-00Ministerio de Ciencia y Tecnología TIN2011-28956-C02Xunta de Galicia 09MRU022291PXunta de Galicia CGL2011-30285-C02-02Xunta de Galicia FP7-SME-2011-BS
A gliclazide complex based on palladium towards Alzheimer's disease: Promising protective activity against Aβ-induced toxicity in: C. elegans
A new palladium coordination compound based on gliclazide with the chemical formula [Pd(glz)2] (where glz = gliclazide) has been synthesized and characterised. The structural characterization reveals that this material consists of mononuclear units formed by a Pd2+ ion coordinated to two molecules of the glz ligand, in which palladium ions exhibit a distorted plane-square coordination sphere. This novel material behaves like a good and selective inhibitor of butyrylcholinesterase, one of the most relevant therapeutic targets against Alzheimer's disease. Analysis of the enzyme kinetics showed a mixed mode of inhibition, the title compound being capable of interacting with both the free enzyme and the enzyme-substrate complex. Finally, the palladium compound shows promising protective activity against Aβ-induced toxicity in the Caenorhabditis elegans model, which has never been reported.he authors gratefully acknowledge funding support from the Spanish Ministry of Science, Innovation and Universities (PGC2018-102052-B-C21 and PID2020-116460RB-I00) and the Junta de Andalućıa (FQM-394 and FQM-134). The authors gratefully acknowledge the funding support of FEDER/Junta de Andalućıa Consejería de Economía y Conocimiento, Grant B-AGR-193-UGR18. O. L. and J. G. F. B. also thank Grant PID2020-116460RB-I00 funded by MCIN/AEI/10.13039/50110 0011033. S. R. acknowledge the Juan de la Cierva Fellowship (IJC2019-038894-I)
2D-Coordination polymers based on 1H-indazole4-carboxylic acid and transition metal ions: magnetic, luminescence and biological properties
We report the formation of five novel multifunctional coordination polymers based on 1H-indazole-4-
carboxylic acid (HL). To the best of our knowledge, these complexes are the first examples of coordination
compounds constructed with this interesting ligand. These materials were synthesized by solvothermal
routes, possess different 2D-structures and show interesting magnetic properties due to the copper
compound showing an unusual spin-canted effect while the anisotropic cobalt material behaves as a fieldinduced single molecule magnet. MTT assays performed on human embryonic kidney (HEK293) and
mouse skin melanoma (B16-F10) cell lines indicated that the Cd-based compound was the only one
exhibiting dose-dependent toxicity on B16-F10 cells, most likely due to the release of toxic Cd(II). Cadmium
and zinc polymers exhibit interesting luminescence properties. The fact that zinc polymers did not exhibit
inherent toxicity against both cancer and non-cancerous cells make this new family an excellent candidate
for further investigation in the field of luminescent materials with biomedical applications.Junta de Andalucia
FQM-394
FQM-1484Red Guipuzcoana de Ciencia, Tecnologia e Innovacion
OF218/2018University of Basque Country
GIU 17/13Basque Government
IT1005-16Spanish Ministry of Science, Innovation and Universities (MCIU/AEI/FEDER, UE)
PGC2018-102052-A-C22
PGC2018-102052-B-C21Junta de Andalucia
FQM-394
FQM-1484European Union (EU)ESFGovernment of the Basque CountryFEDER/MCIU/AEI
RYC-2016-21042
JdC-201
ERK5 Inhibition Induces Autophagy-Mediated Cancer Cell Death by Activating ER Stress
ERK5 kinase; Antitumor drug; ApoptosisKinasa ERK5; Medicament antitumoral; ApoptosiQuinasa ERK5; Medicamento antitumoral; ApoptosisAutophagy is a highly conserved intracellular process that preserves cellular homeostasis by mediating the lysosomal degradation of virtually any component of the cytoplasm. Autophagy is a key instrument of cellular response to several stresses, including endoplasmic reticulum (ER) stress. Cancer cells have developed high dependency on autophagy to overcome the hostile tumor microenvironment. Thus, pharmacological activation or inhibition of autophagy is emerging as a novel antitumor strategy. ERK5 is a novel member of the MAP kinase family that is activated in response to growth factors and different forms of stress. Recent work has pointed ERK5 as a major player controlling cancer cell proliferation and survival. Therefore small-molecule inhibitors of ERK5 have shown promising therapeutic potential in different cancer models. Here, we report for the first time ERK5 as a negative regulator of autophagy. Thus, ERK5 inhibition or silencing induced autophagy in a panel of human cancer cell lines with different mutation patterns. As reported previously, ERK5 inhibitors (ERK5i) induced apoptotic cancer cell death. Importantly, we found that autophagy mediates the cytotoxic effect of ERK5i, since ATG5ˉ/ˉ autophagy-deficient cells viability was not affected by these compounds. Mechanistically, ERK5i stimulated autophagic flux independently of the canonical regulators AMPK or mTORC1. Moreover, ERK5 inhibition resulted in ER stress and activation of the Unfolded Protein Response (UPR) pathways. Specifically, ERK5i induced expression of the ER luminal chaperone BiP (a hallmark of ER stress), the UPR markers CHOP and ATF4, and the spliced form of XBP1. Pharmacological inhibition of UPR with chemical chaperone TUDC, or ATF4 silencing, resulted in impaired ERK5i-mediated UPR, autophagy and cytotoxicity. Overall, our results suggest that ERK5 inhibition induces autophagy-mediated cancer cell death by activating ER stress. Since ERK5 inhibition sensitizes cancer cells and tumors to chemotherapy, future work will determine the relevance of UPR and autophagy in the combined use of chemotherapy and ERK5i to tackle Cancer.This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO, grant SAF2015-64237-R), the Spanish Ministry of Science and Innovation (Grant PID2019-107561RB-I00), and cofounded by the European Regional Development Fund (ERDF)
A Luminescent MOF Based on Pyrimidine-4,6-dicarboxylate Ligand and Lead(II) with Unprecedented Topology
In the present work, we report on a 3D MOF of {[Pb5(μ3-OH)(μ3-NO3)3(μ6-pmdc)3]·H2O}n formula (pmdc = pyrimidine-4,6-dicarboxylate) synthesized by an oven-heated, solvent-free procedure. The large connectivity afforded by the three ligands in their coordination to lead(II) ions grows cubic building units characterized by a central Pb atom with an unusual coordination index of 12 and 6 pmdc ligands occupying the faces. These cubic units are linked to one another giving rise to a quite condensed structure that represents an unprecedented topology showing the (4·62)6(43)2(45·610)3(45·68·82)6(46·69)6(612·83) point symbol. The crystalline material has been characterized by routine physico-chemical techniques to confirm its purity, and its thermal behaviour has been also studied by thermogravimetric and thermodiffractometric analyses. The solid presents a greenish blue photoluminescent emission based on pmdc ligands, as revealed by time-dependent density-functional theory (TDDFT) calculations, which is substantially more intense than in the free H2pmdc ligand according to its improved quantum yield. The emissive capacity of the material is further analysed according to decreasing temperature of the polycrystalline sample, finding that sizeable, long-lasting phosphorescence is present.This research was funded by Gobierno Vasco/Eusko Jaurlaritza (IT1755-22, IT1722-22 and IT1500-22) and Junta de Andalucía (ProyExcel_00386 and FQM-394). This publication is also part of the I+D+i projects of PGC2018-102052-A-C22 and PGC2018-102052-B-C21 codes, funded by MCIN/ AEI/10.13039/501100011033/ and “FEDER Una manera de hacer Europa”
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