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A multi-integrated approach on toxicity effects of engineered TiO2 nanoparticles

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Frontiers of Environmental Science & Engineering 2015年第5期9卷 793-803页

作者： Ana PICADO Susana M. PAIXAO Liliana MOITA Luis SILVA Mario S. DINIZ Joana LOURENCO Isabel PERES Luisa CASTRO jose Brito CORREIA Joana PEREIRA Isabel ferreira Antonio pedro Alves MATOS pedro BARQUINHA Elsa MENDONCA LNEG-National Laboratory of Energy and Geology I.P. Lisbon 1649-038 Portugal REQUIMTE Chemistry Department Fine Chemistry and Biotechnology Center Faculty of Sciences and Technology New University of Lisbon Caparica 2829-516 Portugal IMAR-Ocean Institute Department of Sciences and Environmental Engineering Faculty of Sciences and Technology New University of Lisbon Caparica 2829-516 Portugal CENIMAT/I3N and Department of Materials Science Faculty of Sciences and Technology New University of Lisbon Caparica 2829-516 Portugal Pathological Anatomy Curry Cabml Hospital Lisbon 1069-166 Portugal CESAM Faculty of Sciences Lisbon University Lisbon 1749-016 Portugal

The new properties of engineered nanoparti- cles drive the need for new knowledge on the safety, fate, behavior and biologic effects of these particles on organisms and ecosystems. Titanium dioxide nanoparticles have been used extensively for a wide range of applica- tions, e.g, self-cleaning surface coatings, solar cells, water treatment agents, topical sunscreens. Within this scenario increased environmental exposure can be expected but data on the ecotoxicological evaluation ofnanoparticles are still scarce. The main purpose of this work was the evaluation of effects of TiO2 nanoparticles in several organisms, covering different trophic levels, using a battery of aquatic assays. Using fish as a vertebrate model organism tissue histological and ultrastructural observations and the stress enzyme activity were also studied. TiO2 nanoparticles （Aeroxide~ P25）, two phase composition ofanatase （65%） and rutile （35%） with an average particle size value of 27.64-11 nm were used. Results on the ECs0 for the tested aquatic organisms showed toxicity for the bacteria, the algae and the crustacean, being the algae the most sensitive tested organism. The aquatic plant Lemna minor showed no effect on growth. The fish Carassius auratus showed no effect on a 21 day survival test, though at a biochemical level the cytosolic Glutathione-S-Transferase total activity, in intestines, showed a general significant decrease （p〈0.05） after 14 days of exposure for all tested concentrations. The presence of TiO2 nanoparticles aggregates were observed in the intestine lumen but their internalization by intestine cells could not be confirmed.

关键词： ecotoxicity enzymatic analysis histology,transmission electron microscopy (TEM) TiO2-nanoparti-cles

Improving surface integrity when drilling CFRPs and Ti-6Al-4V using sustainable lubricated liquid carbon dioxide

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Chinese Journal of Aeronautics 2023年第7期36卷 129-146页

作者： In˜igo RODRIGUEZ pedro jose´ARRAZOLA Mikel CUESTA Luka STERLE Franci PUSˇAVEC Faculty of Engineering Mondragon UnibertsitateaArrasate-Mondragon 20500Spain Faculty of Mechanical Engineering University of LjubljanaLjubljana 1000Slovenia

In the quest for decreasing fuel consumption and resulting gas emissions in the aeronautic sector,lightweight materials such as Carbon Fiber Reinforced Polymers(CFRPs)and Ti-6Al-4V alloys are being *** materials,with excellent weight-to-strength ratios,are widely used for structural applications in aircraft *** date,several studies have been published showing that the use of metalworking fluids(MWFs),special tool geometries,or advanced machining techniques is required to ensure a surface quality that meets aerospace component *** MWFs pose a number of environmental and worker health hazards and also degrade the mechanical properties of CFRPs due to water absorption in the ***,a transition to more environmentally friendly cooling/lubrication techniques that prevent moisture problems in the composite is *** research shows that lubricated LCO_(2) is a viable option to improve the quality of drilled CFRP and titanium aerospace components compared to dry machining,while maintaining clean work *** results show that the best combination of tool geometry and cooling conditions for machining both materials is drilling with Brad point drills and lubricated LCO_(2).Drilling under these conditions resulted in a 90%improvement in fiber pullout volume compared to dry machined CFRP *** addition,a 33% reduction in burr height and a 15% improvement in surface roughness were observed compared to dry drilling of titanium.

关键词： Carbon fibers Cryogenics Green manufacturing Machining Solid lubricants Surface morphology Titanium alloys

Macular atrophy after combined intravitreal triamcinolone and photodynamic therapy to treat choroidal neovascularization

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International Journal of Ophthalmology(English edition) 2010年第2期3卷 161-163页

作者： jose M Ruiz-Moreno Javier A Montero pedro Amat Francisco Lugo Department of Ophthalmology Albacete Medical SchoolUniversity of Castilla La ManchaSpain Alicante Institute of Ophthalmology Vitreo-Retinal Unit.Spain Pio del Rio Hortega University Hospital Ophthalmology UnitValladolidSpain

AIMTo report the appearance of choriocapillaris atrophy after combined high dose intravitreal triamcinolone acetonide (TA) and photodynamic therapy (PDT) to treat choroidal neovascularization (CNV) associated with age... 详细信息

关键词： age related macular degeneration choriocapillaris atrophy intravitreous triamcinolone photodynamic therapy retinal pigment epithelium atrophy

Biotinylated polyurethane-urea nanoparticles for targeted theranostics in human hepatocellular carcinoma

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Nano Research 2015年第5期8卷 1729-1745页

作者： Genoveva MorraI-Ruiz pedro Melgar-Lesmes Andrea Lopez-Vicente Conxita Solans Maria jose Garcia-Celma Department of Pharmacy and Pharmaceutical Technology Faculty of Pharmacy University of Barcelona Av Joan XXIII s/n 08028 Barcelona Spain Institute of Advanced Chemistry of Catalonia (IQAC) CS/C Jordi Girona 18-26 08034 Barcelona Spain Networking Research Center on Bioengineering Biomaterials and Nanomedicine CIBER-BBN Spain

Over the past years, significant efforts have been devoted to explore novel drug delivery and detection strategies for simultaneous therapy and diagnostics. The development of biotinylated polyurethane-urea nanoparticles as theranostic nanocarriers for targeted drug and plasmid delivery, for fluorescence detection of human hepatocellular carcinoma cells, is described herein. These targeted nanoparticles are specifically designed to incorporate biotin into the polymeric matrix, since many tumor types overexpress receptors for biotin as a mechanism to boost uncontrolled cell growth. The obtained nanoparticles were spherical, exhibited an average diameter ranging 110-145 nm, and showed no cytotoxicity in healthy endothelial cells. Biotinylated nanoparticles are selectively incorporated into the perinuclear and nuclear area of the human hepatocellular carcinoma cell line, HepG2, in division, but not into growing, healthy, human endothelial cells. Indeed, the simultaneous incorporation of the anticancer drugs, phenoxodiol or sunitinib, together with plasmid DNA encoding green fluorescent protein, into these nanoparticles allows a targeted pharmacological antitumor effect and furthermore, selective transfection of a reporter gene, to detect these cancer cells. The combined targeted therapy and detection strategy described here could be exploited for liver cancer therapy and diagnostics, with a moderate safety profile, and may also be a potential tool for other types of cancer.

关键词： cancer therapy DNA nanoparticles polyurethane theranostics

Pupil apodization for increasing data storage density

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Chinese Optics Letters 2009年第8期7卷 720-723页

作者： Vidal F.Canales pedro J.Valle jose E.Oti Manuel P.Cagigal Department of Física Aplicada University of CantabriaLos Castros S/NSantander 39005Spain AOTEK S.COOP. Bo San Andrés 19Arrasate-Mondragón 20500Spain

We introduce a technique for increasing density in optical data storage systems. This technique is based on the use of a superresolving filter at the pupil of a confocal readout system. The main characteristic of this confocal readout system is that the light beam traverses twice through the pupil filter. We describe how to analyze the system performance for general filters, but we focus the study on filters with no focus displacement. Although the storage density attainable depends on the filter characteristics, we show that the storage density can be easily duplicated.

关键词： Pupil apodization for increasing data storage density PSF data

Conformal and continuous deposition of bifunctional cobalt phosphide layers on p-silicon nanowire arrays for improved solar hydrogen evolution

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Nano Research 2018年第9期11卷 4823-4835页

作者： Sitaramanjaneva Mouli Thalluri Jerome Borme Kang Yu Junyuan Xu Isilda Amorim Joao Gaspar Liang Qiao Paulo ferreira pedro Alpuim Lifeng Liu International Iberian Nanotechnology Laboratory (INL) Av. Mestre. Jose Veiga Braga 4715-330 Portugal Materials Science and Engineering Program University of Texas at Austin Austin TX78712 USA Deportment of Chemistry State Key Laboratory of Molecular Engineering of Polymers and Institute of Biomedical Sciences Fudon University Shanghai 200433 China Mechanical Engineering Department and IDMEC Instituto Superior Tdcnico University of Lisbon Av. Rovisco Pais Lisboa 1049-007 Portugal Center of Physics University of Minho Braga 4710-057 Portugal

Vertically aligned p-silicon nanowire （SiNW） arrays have been extensively investigated in recent years as promising photocathodes for solar-driven hydrogen evolution. However, the fabrication of SiNW photocathodes with both high photoelectrocatalytic activity and long-term operational stability using a simple and affordable approach is a challenging task. Herein, we report conformal and continuous deposition of a di-cobalt phosphide （C02P） layer on lithography- patterned highly ordered SiNW arrays via a cost-effective drop-casting method followed by a low-temperature phosphorization treatment. The as-deposited C02P layer consists of crystalline nanoparticles and has an intimate contact with SiNWs, forming a well-defined SiNW@Co2P core/shell nanostructure. The conformal and continuous Co2P layer functions as a highly efficient catalyst capable of substantially improving the photoelectrocatalytic activity for the hydrogen evolution reaction （HER） and effectively passivates the SiNWs to protect them from photo-oxidation, thus prolonging the lifetime of the electrode. As a consequence, the SiNW@Co2P photocathode with an optimized C02P layer thickness exhibits a high photocurrent density of -21.9 mA·cm^-2 at 0 V versus reversible hydrogen electrode and excellent operational stability up to 20 h for solar-driven hydrogen evolution, outperforming many nanostructured silicon photocathodes reported in the literature. The combination of passivation and catalytic functions in a single continuous layer represents a promising strategy for designing high-performance semiconductor photoelectrodes for use in solar-driven water splitting, which may simplify fabrication procedures and potentially reduce production costs.

关键词： solar-driven hydrogenevolution silicon nanowire cobalt phosphide photoelectrochemical water splitting drop-casting

A Feature Selection Strategy to Optimize Retinal Vasculature Segmentation

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Computers, Materials & Continua 2022年第2期70卷 2971-2989页

作者： jose Escorcia-Gutierrez Jordina Torrents-Barrena Margarita Gamarra Natasha Madera pedro Romero-Aroca Aida Valls Domenec Puig Electronic and Telecommunications Engineering Program Universidad Autónoma del CaribeBarranquilla080001Colombia Department of Computational Science and Electronic Universidad de la CostaCUCBarranquilla080001Colombia Ophthalmology Service Universitari Hospital Sant JoanInstitut de Investigacio Sanitaria Pere VirgiliReus43201Spain Departament d’Enginyeria Informàtica i Matemàtiques Escola Tècnica Superior d’EnginyeriaUniversitat Rovira i VirgiliTarragona43007Spain

Diabetic retinopathy (DR) is a complication of diabetesmellitus thatappears in the retina. Clinitians use retina images to detect DR pathologicalsigns related to the occlusion of tiny blood vessels. Such occlusion brings adegenerative cycle between the breaking off and the new generation of thinnerand weaker blood vessels. This research aims to develop a suitable retinalvasculature segmentation method for improving retinal screening proceduresby means of computer-aided diagnosis systems. The blood vessel segmentationmethodology relies on an effective feature selection based on SequentialForward Selection, using the error rate of a decision tree classifier in theevaluation function. Subsequently, the classification process is performed bythree alternative approaches: artificial neural networks, decision trees andsupport vector machines. The proposed methodology is validated on threepublicly accessible datasets and a private one provided by Hospital Sant Joanof Reus. In all cases we obtain an average accuracy above 96% with a sensitivityof 72% in the blood vessel segmentation process. Compared with the state-ofthe-art, our approach achieves the same performance as other methods thatneed more computational *** method significantly reduces the numberof features used in the segmentation process from 20 to 5 dimensions. Theimplementation of the three classifiers confirmed that the five selected featureshave a good effectiveness, independently of the classification algorithm.

关键词： Diabetic retinopathy artificial neural networks decision trees support vector machines feature selection retinal vasculature segmentation

Plant growth and nutrient use efficiency of two native Fabaceae species for mineland revegetation in the eastern Amazon

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Journal of Forestry Research 2020年第6期31卷 2287-2293页

作者： Silvio J.Ramos Markus Gastauer Simone K.Mitre Cecı´lio F.Caldeira Joyce R.Silva Antonio E.Furtini Neto Guilherme Oliveira pedro W.M.Souza filho jose´O.Siqueira Instituto Tecnolo´gico Vale Rua Boaventura da Silva955Belem 66055-090Brazil Departamento de Ciencia do Solo Universidade Federal de LavrasLavras 37200-000Brazil

The primary challenge of mineland revegetation is the establishment of species able to cope with low availability of nutrients,especially in steep slopes such as of mine *** evaluated plant growth response and nutrient use efficiency(NUE)of two promising native Fabaceae species(Dioclea apurensis—liana from metalliferous savannas;Bauhinia longipedicellata—tree from Amazon rainforest)from the Caraja´s Mineral Province,eastern *** were grown separately in 2-kg pots filled with mining *** were fertilized with nitrogen,phosphorus,potassium(NPK),lime,and *** results showed increments on growth of both species when nutrients were applied to the mining *** showed increases in leaf area,plant height,stem diameter,and shoot dry mass production when NPK or NPK?micronutrients were applied,while *** was responsive to application of NPK?lime or NPK?lime?***,*** showed higher NUE than ***,especially at the lowest doses of N,P and *** findings may indicate a substantial advantage of *** for mineland revegetation,as this species may require lower nutrient inputs,being,therefore,a more sustainable way to revegetate degraded areas.

关键词： Fertilizer application Mining soil Tropical forest Nutrient use efficiency

MicroRNAs expression dynamics reveal post-transcriptional mechanisms regulating seed development in Phaseolus vulgaris L.

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Horticulture Research 2021年第1期8卷 195-211页

作者： jose Ricardo Parreira Michela Cappuccio Alma Balestrazzi pedro Fevereiro Susana de Sousa Araujo Instituto de Tecnologia Quimica e Biologica Antonio Xavier Universidade Nova de LisboaAvenida da Republica2780-157 OeirasPortugal Department of Biology and Biotechnology“L.Spallanzani” University of Paviavia Ferrata 927100 PaviaItaly InnovPlantProtect Collaborative Laboratory Estrada de Gil Vaz7351-901 ElvasPortugal Present address:Association BLC3-Technology and Innovation Campus Centre Bio R&D UnitRua Nossa Senhora da Conceicao 2Lagares da Beira3405-155 Oliveira do HospitalPortugal

The knowledge on post-transcriptional regulation mechanisms implicated in seed development(SD)is still limited,particularly in one of the most consumed grain legumes,Phaseolus vulgaris *** explore for the first time the miRNA expression dynamics in *** developing ***-two known and 39 new miRNAs were found expressed in *** developing *** of the miRNAs identified were more abundant at 10 and 40 days after anthesis,suggesting that late embryogenesis/early filling and desiccation were SD stages in which miRNA action is more *** analysis and target prediction identified targets for 77 expressed *** several known miRNAs were predicted to target HD-ZIP,ARF,SPL,and NF-Y transcription factors families,most of the predicted targets for new miRNAs encode for functional ***-targets expression profiles evidenced that these miRNAs could tune distinct seed developmental *** more accumulated at early SD stages were implicated in regulating the end of embryogenesis,postponing the seed maturation program,storage compound synthesis and *** more accumulated at late SD stages could be implicated in seed quiescence,desiccation tolerance,and longevity with still uncovered roles in *** miRNAs herein described represent novel *** resources with potential application in future biotechnological approaches to modulate the expression of genes implicated in legume seed traits with impact in horticultural production systems.

关键词： mechanisms dynamics regulating