Design of New Materials for Passive Vibration Control

The objective of this contribution is to extend the models of cellular/composite material design to nonlinear material behaviour and apply them for design of materials for passive vibration control. As a first step a computational tool allowing determination of optimised one-dimensional isolator behaviour was developed. This model can serve as a representation for idealised macroscopic behaviour. Optimal isolator behaviour to a given set of loads is obtained by generic probabilistic metaalgorithm, simulated annealing. Cost functional involves minimization of maximum response amplitude in a set of predefined time intervals and maximization of total energy absorbed in the first loop. Dependence of the global optimum on several combinations of leading parameters of the simulated annealing procedure, like neighbourhood definition and annealing schedule, is also studied and analyzed. Obtained results facilitate the design of elastomeric cellular materials with improved behaviour in terms of dynamic stiffness for passive vibration control

A method for the optimal design of composite continuum structures

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76840/1/AIAA-1998-4984-312.pd

Design of New Materials for Passive Vibration Control

The aim of this contribution is to extend the techniques of composite materials design to non-linear material behaviour and apply it for design of new materials for passive vibration control. As a first step a computational tool allowing determination of macroscopic optimized one-dimensional isolator behaviour was developed. Voigt, Maxwell, standard and more complex material models can be implemented. Objective function considers minimization of the initial reaction and/or displacement peak as well as minimization of the steady-state amplitude of reaction and/or displacement. The complex stiffness approach is used to formulate the governing equations in an efficient way. Material stiffness parameters are assumed as non-linear functions of the displacement. The numerical solution is performed in the complex space. The steady-state solution in the complex space is obtained by an iterative process based on the shooting method which imposes the conditions of periodicity with respect to the known value of the period. Extension of the shooting method to the complex space is presented and verified. Non-linear behaviour of material parameters is then optimized by generic probabilistic meta-algorithm, simulated annealing. Dependence of the global optimum on several combinations of leading parameters of the simulated annealing procedure, like neighbourhood definition and annealing schedule, is also studied and analyzed. Procedure is programmed in MATLAB environment

Simultaneous design of structural topology and material properties

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77309/1/AIAA-2000-4913-878.pd

Multifunctional graphene-based magnetic nanocarriers optimized with copolymer Pluronic F127 for biomedical applications

The limitations of current cancer therapies prompt the urgent need for a more effective therapeutic strategy [1]. Graphene-based magnetic nanoparticles (GbMNPs) due to their unique properties, such as high chemical and thermal stability, high charge carrier mobility, large surface area for functionalization and superparamagnetic properties, have the potentiality to be used as efficient multifunctional nanocarrier systems [2]. However, one of the challenges of GbMNPs in biomedical applications is their tendency for agglomeration or precipitation in electrolyte solutions, such as those of body fluids [3]. To overcome this drawback, the developed GbMNPs were grafted with copolymer Pluronic F127 (PF127), yielding the materials denoted as GbMNPs@PF127. PF127 is a water-soluble and biocompatible triblock copolymer (PEO100-PPO65-PEO100) approved by the U.S. Food and Drug Administration (FDA) for use as food additive and in pharmaceutical formulations [4]. This grafting strategy allows the incorporation of a hydrophilic corona that reduces the aggregation of nanoparticles and the adsorption of blood proteins [4, 5]. Also, increases the biocompatibility of the nanosystems and its colloidal stability, prolonging blood circulation [5]. In this study, GbMNPs@PF127 were covalently conjugated with Doxorubicin (DOX), a highly effective chemotherapeutic drug against a broad spectrum of cancers. The developed therapeutic nanosystems were characterized and investigated to be used as multifunctional nanocarriers to combine thermo-chemotherapy, revealing exceptional features, such as: (i) high loading of the chemotherapeutic drug DOX; (ii) high pH stimuli-responsive controlled release; (iii) high heating efficiency profile under AMF with thermo-responsive drug release; as well as (iv) good haem- and biocompatibility even at high concentrations. The presented strategy and findings can represent a new way to design and synthesize highly stable graphene-based materials with novel structures for synergetic thermo-chemotherapy triggered by the abnormal cell microenvironment for a more effective treatment of cancer.This work was financially supported by: Project POCI-01-0145-FEDER-006984 Associate Laboratory LSRE-LCM funded by FEDER through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) - and by nationalfunds through FCT - Fundação para a Ciência e Tecnologia R.O.R. acknowledgs the PHD scholarship SFRH/BD/97658/2013 granted by FCT. A.M.T.S. acknowledges the FCT Investigator 2013 Programme (IF/01501/2013), with financing from the European Social Fund and the Human Potential Operational Programme.info:eu-repo/semantics/publishedVersio

Multifunctional graphene-based magnetic nanocarriers for combined hyperthermia and dual stimuli-responsive drug delivery

The synthesis of hydrophilic graphene-based yolk-shell magnetic nanoparticles functionalized with copolymer pluronic F-127 (GYSMNP@PF127) is herein reported to achieve an efficient multifunctional biomedical system for mild hyperthermia and stimuli-responsive drug delivery. In vitro tests revealed the extraordinary ability of GYSMNP@PF127 to act as smart stimuli-responsive multifunctional nanomedicine platform for cancer therapy, exhibiting (i) an outstanding loading capacity of91% (w/w,representing 910μgmg−1) of the chemotherapeutic drug doxorubicin, (ii) a high heating efficiency under an alternating (AC) magnetic field (intrinsic power loss ranging from 2.1–2.7nHm2kg−1), and (iii) a dual pH and thermal stimuli-responsive drug controlled release (46% at acidic tumour pH vs 7% at physiological pH) under AC magnetic field, in just 30min. Additionally, GYSMNP@PF127 presents optimal hydrodynamic diameter (DH=180nm) with negative surface charge, high haemocompatibility for blood stream applications and tumour cellular uptake of drug nanocarriers. Due to its physicochemical, magnetic and biocompatibility properties, the developed graphene-based magnetic nanocarrier shows high promise as dual exogenous (AC field)/endogenous (pH) stimuli-responsive actuators for targeted thermo-chemotherapy, combining magnetic hyperthermia and controlled drug release triggered by the abnormal tumour environment. The presented strategy and findings can represent a new way to design and develop highly stable added-value graphene-based nanostructures for the combined treatment of cancer.This work was financially supported by: Project POCI-01-0145- FEDER-006984 – Associate Laboratory LSRE-LCM funded by FEDER through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) – and by national funds through FCT - Fundação para a Ciência e a Tecnologia, and by project NORTE-01- 0145-FEDER-029394, RTChip4Theranostics, supported by Programa Operacional Regional do Norte - Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF) and by Fundação para a Ciência e Tecnologia (FCT), IP. R.O.R. acknowledges the Ph.D. scholarship SFRH/BD/97658/2013 granted by FCT. A.M.T.S acknowledges the FCT Investigator 2013 Programme (IF/ 01501/2013), with financing from the European Social Fund and the Human Potential Operational Programme. G.D. acknowledges financing by Slovene Research Agency (J2-6754). M. B. acknowledges financial funding from POCTEP (Co-operational Programme for Crossborder Cooperation Spain-Portugal). This article is based upon work from COST Action RADIOMAG (TD1402), supported by COST (European Cooperation in Science and Technology).info:eu-repo/semantics/publishedVersio

Monitoring ten insect pests in selected orchards in three Azorean Islands : The project CUARENTAGRI

BACKGROUND: The data we present are part of the CUARENTAGRI project, which involves all archipelagos of the Macaronesia (Azores, Madeira, Canary Islands and Cabo Verde). The project aims to: i) identify and evaluate the risks associated with the introduction of new arthropod pests; ii) study the population dynamics of selected arthropod pest species currently responsible for the damage of key target crops and iii) develop monitoring systems, based on prediction and/or population dynamics of the crop pests, creating warnings and a phytosanitary prevention system. In this contribution, we compile data for three Azorean Islands (Terceira, São Jorge and São Miguel Islands), where pheromone-baited traps were placed in pastures, potato fields and several orchards’ types (apples, banana, chestnuts, olives, orange and strawberry), during three consecutive years (2020, 2021 and 2022). NEW INFORMATION: A total of 114,827 specimens of insects (Arthropoda, Insecta) were collected, belonging to four orders, six families and ten recorded pest species. A total of eight species are considered introduced (Cosmopolites sordidus (Germar, 1824), Drosophila suzukii (Matsumura, 1931), Bactrocera oleae (Rossi, 1790), Ceratitis capitata (Wiedemann, 1824), Phthorimaea operculella (Zeller, 1873), Cydia pomonella (Linnaeus, 1758), Cydia splendana (Hübner, 1799) and Grapholita molesta (Busck, 1916); n = 84,986 specimens) and two native non-endemic (Mythimna unipuncta (Haworth, 1809) and Spodoptera littoralis (Boisduval, 1833); n = 17,465 specimens). This study intended to contribute to a better knowledge of the arthropods pests that can affect the Azorean crops and will serve as a baseline for future monitoring actions, pest risk assessments and prevention systems.This work was financed under the project CUARENTAGRI by Cooperation Programs INTERREG V A (Spain-Portugal) and MAC 2014-2020. Darwin Core Database management was funded by the Project project FCT-UIDB/00329/2020-2024 (Thematic Line 1 – integrated ecological assessment of environmental change on biodiversity) and Portal da Biodiversidade dos Açores (2022-2023) - PO Azores Project - M1.1.A/INFRAEST CIENT/001/2022. Lucas Lamelas-Lopez was supported by the Project FCT-UIDP/00329/2020-2023.info:eu-repo/semantics/publishedVersio

A tailor-made protocol to synthesize yolk-shell graphene-based magnetic nanoparticles for nanomedicine

A simple tailor-made protocol to synthesize graphene-based magnetic nanoparticles (GbMNPs) for nanomedicine is herein reported. Different GbMNPs with very distinctive physicochemical and toxicological properties were synthesized by adjusting the number of carbon precursors in the coating of superparamagnetic iron oxide nanoparticles. In vitro tests show the ability to use these GbMNPs as intelligent and on-demand drug nanocarrier systems for drug delivery, exhibiting the following features: good colloidal stability, good loading capacity of the chemotherapeutic drug doxorubicin, high pH-controlled release of the encapsulated drug (targeting tumour acidic pH conditions), superparamagnetic behaviour and biocompatibility. Due to their combined properties (i.e., physicochemical, magnetic, and biocompatibility), GbMNPs show high potentiality to be combined with other biomedical techniques, such as magnetic hyperthermia, which can represent an enhancement in the treatment of cancer.This research was funded by Project POCI-01-0145-FEDER-006984 - Associate Laboratory LSRE-LCM funded by FEDER through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI) - and by national funds through FCT - Fundação para a Ciência e a Tecnologia, and by project NORTE-01-0145-FEDER-029394, RTChip4Theranostics, supported by Programa Operacional Regional do Norte - Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF) and by Fundação para a Ciência e Tecnologia (FCT), IP.R.O.R. acknowledges the Ph.D. scholarship SFRH/BD/97658/2013 granted by FCT. G.D. acknowledges financing by Slovene Research Agency (J2-6754). The authors also would like to acknowledge the financial support provided by COST—European Cooperation in Science and Technology, in the form of a short term scientific mission (STSM) granted by COST Action TD1402: RADIOMAG.info:eu-repo/semantics/publishedVersio