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1.
Comput Struct Biotechnol J ; 25: 105-126, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38974014

RESUMO

The adoption of innovative advanced materials holds vast potential, contingent upon addressing safety and sustainability concerns. The European Commission advocates the integration of Safe and Sustainable by Design (SSbD) principles early in the innovation process to streamline market introduction and mitigate costs. Within this framework, encompassing ecological, social, and economic factors is paramount. The NanoSafety Cluster (NSC) delineates key safety and sustainability areas, pinpointing unresolved issues and research gaps to steer the development of safe(r) materials. Leveraging FAIR data management and integration, alongside the alignment of regulatory aspects, fosters informed decision-making and innovation. Integrating circularity and sustainability mandates clear guidance, ensuring responsible innovation at every stage. Collaboration among stakeholders, anticipation of regulatory demands, and a commitment to sustainability are pivotal for translating SSbD into tangible advancements. Harmonizing standards and test guidelines, along with regulatory preparedness through an exchange platform, is imperative for governance and market readiness. By adhering to these principles, the effective and sustainable deployment of innovative materials can be realized, propelling positive transformation and societal acceptance.

2.
Regul Toxicol Pharmacol ; 139: 105360, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36804527

RESUMO

Over the recent years, EU chemicals legislation, guidance and test guidelines have been developed or adapted for nanomaterials to facilitate safe use of nanomaterials. This paper provides an overview of the information requirements across different EU regulatory areas. For each information requirement, a group of 22 experts identified potential needs for further action to accommodate guidance and test guidelines to nanomaterials. Eleven different needs for action were identified, capturing twenty-two information requirements that are specific to nanomaterials and relevant to multiple regulatory areas. These were further reduced to three overarching issues: 1) resolve issues around nanomaterial dispersion stability and dosing in toxicity testing, in particular for human health endpoints, 2) further develop tests or guidance on degradation and transformation of organic nanomaterials or nanomaterials with organic components, and 3) further develop tests and guidance to measure (a)cellular reactivity of nanomaterials. Efforts towards addressing these issues will result in better fit-for-purpose test methods for (EU) regulatory compliance. Moreover, it secures validity of hazard and risk assessments of nanomaterials. The results of the study accentuate the need for a structural process of identification of information needs and knowledge generation, preferably as part of risk governance and closely connected to technological innovation policy.


Assuntos
Segurança Química , Nanoestruturas , Humanos , Nanoestruturas/toxicidade , Políticas , Medição de Risco/métodos , Testes de Toxicidade/métodos
3.
Methods Mol Biol ; 2495: 327-366, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35696041

RESUMO

The increasingly widespread use of genome editing brought with it a fierce debate about the most adequate regulation of this latest innovation in modern biotechnology and the products resulting from it. In almost all cases, this debate has become a repetition or continuation of the deliberations concerning genetically modified organisms (GMOs) of the 1990s and early 2000s.This chapter aims to untangle the historically influenced and often biased arguments of the debates by addressing the complex question of the correct interpretation of relevant underlying law and its applicability. In doing so, the chapter considers 25 countries and regions that have published results or ongoing investigations and discussions pertaining to the governance of genome editing in their jurisdictions: 16 have published policies or signed statements that exempt gene edited plants from GMO-regulations, as long as no foreign DNA or transgene remained in the final product. Such exemptions are based on the widely supported acceptance that the products of the underlying genome editing processes resemble those of "conventional breeding" techniques. These policies and statements often refer to the important role that modern precision biotechnologies, of which genome editing is one, play in addressing some of the world's overarching challenges, such as the loss of biodiversity, pest and disease control, and climate change; they are furthermore shown to exhibit an adherence to the four universal principles of good regulation: (a) proportionality, (b) non-discrimination, (c) predictability, and (d) enforceability. And while it is the right of jurisdictions to develop their own regulations independent from that of their neighbors, it is specifically the principle of "enforceability" that may become the ultimate litmus test of those regulations that do not grant exemptions from GMO-regulations.


Assuntos
Alimentos Geneticamente Modificados , Edição de Genes , Agricultura , Biotecnologia , Edição de Genes/métodos , Plantas Geneticamente Modificadas/genética , Políticas
6.
Transgenic Res ; 28(3-4): 419-463, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31309374

RESUMO

The "OECD Conference on Genome Editing: Applications in Agriculture-Implications for Health, Environment and Regulation" was held on the 28-29 June 2018 at the OECD headquarter and conference centre in Paris, France. It brought together policy makers, academia, innovators and other stakeholders involved in the topic, in order to take stock of the current technical developments and implementations of genome editing, as well as their applications in various areas of agriculture and the implications they give rise to (More information on the "OECD Conference on Genome Editing: Applications in Agriculture-Implications for Health, Environment and Regulation" can be found on the OECD Genome Editing hub: http://www.oecd.org/environment/genome-editing-agriculture/ ; the hub also contains the detailed conference programme, the biographies of all conference speakers, the detailed conference abstracts, and the presentations of the two-day conference). The conference aimed to provide a clearer understanding of the regulatory considerations raised by products of genome editing, pointing towards a coherent policy approach to facilitate innovations involving genome editing.


Assuntos
Agricultura , Meio Ambiente , Edição de Genes/legislação & jurisprudência , Edição de Genes/métodos , Saúde Global , Organização para a Cooperação e Desenvolvimento Econômico , Sistemas CRISPR-Cas , Congressos como Assunto , Edição de Genes/normas , Humanos , Relatório de Pesquisa
7.
Trends Biotechnol ; 37(10): 1029-1032, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31229272

RESUMO

The international Organisation for Economic and Co-operative Development (OECD) conference on genome editing (June 2018) provided a timely platform for scientists, risk assessors, policy-makers, and regulators to discuss the applications and implications of this technology in various agriculture areas and the related policy considerations; in addition questions related to appropriate safety assessments and the regulation of genome-edited products were debated.


Assuntos
Agricultura/métodos , Inocuidade dos Alimentos , Edição de Genes/legislação & jurisprudência , Agricultura/legislação & jurisprudência , Animais , Animais Geneticamente Modificados , Cruzamento , Produtos Agrícolas/genética , Organização para a Cooperação e Desenvolvimento Econômico , Plantas Geneticamente Modificadas/genética , Opinião Pública , Fatores de Risco
9.
Acta Crystallogr C ; 62(Pt 12): m623-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17148904

RESUMO

Bis(1,3-thiazolidine-2-thione-kappaS2)gold(I) bis(4-chlorobenzenesulfonyl)amide, [Au(C3H5NS2)2](C12H8Cl2NS2O4), has no imposed symmetry. Classical N-H...N and N-H...O hydrogen bonds link the residues to form chains parallel to the b axis. Weaker interactions involve C-H...O, C-H...Au and a number of X...Cl contacts (X = Cl, S or Au) clustered in the region y approximately equal to 1/4}. In bis(1-methylimidazolidine-2-thione-kappaS2)gold(I) bis(4-iodobenzenesulfonyl)amide, [Au(C4H8N2S)2](C12H8I2NS2O4), the Au atom of the cation and the N atom of the anion lie on the twofold axis (0, y, 1/4}) in the space group C2/c. The formula unit forms a self-contained ring with two symmetry-equivalent N-H...O hydrogen bonds, and weak C-H...X (X = O, I or S), Au...I and I...I contacts are observed. In both compounds, the anions display extended conformations.

10.
Small ; 2(6): 774-84, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17193122

RESUMO

Multi-walled carbon nanotubes were synthesized by chemical vapor deposition from pure toluene and toluene/diazine mixtures using ferrocene as a catalyst precursor at 760 degrees C. As recently announced, characterization of the resulting nanotube films showed that, unlike pure carbon nanotubes, those grown in the presence of nitrogen have an extremely high degree of internal order, both in terms of the uniform chirality in the nanotube walls and of the crystallographic register between them. Here, the structure, defects, and morphology of the nanotubes were analyzed in depth using advanced electron microscopy techniques, and compared with existing models and observations. Nitrogen, which seems to be responsible for the dramatic structural order, was found to segregate preferentially within the core of the nanotubes.


Assuntos
Cristalização/métodos , Modelos Químicos , Modelos Moleculares , Nanotecnologia/métodos , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Nitrogênio/química , Simulação por Computador , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de Superfície
11.
Acta Crystallogr A ; 62(Pt 4): 287-95, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16788268

RESUMO

Molecular dynamics computer simulation models are employed to study the direct filling of single-walled carbon nanotubes (which vary in diameter) with an archetypal metal trihalide, LaCl3. The use of relatively simple potential models allows the investigation of details of both the atomistic filling mechanism and the thermodynamic factors controlling the formation. The resulting low-dimensional crystallites are analysed with respect to bulk crystal structures and compared to experimental high-resolution transmission-electron-microscopy images by simulation of equivalent micrographs from one of the obtained potential models, resulting in excellent agreement between the simulated and experimental images.

12.
Chemphyschem ; 6(2): 300-5, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15751353

RESUMO

Simple binary solids can be found to adopt unprecedented structures when confined into nanometre-sized cavities, such as the inner cylindrical bore of single-walled carbon nanotubes (SWNT). In the case of the discussed Lal(x)@SWNT encapsulation composite, the Lal2 "crystal" fragment adopts the structure of bulk Lal3, with one third of the iodine positions unoccupied. A complete characterisation of the encapsulation composite was achieved using an enhanced digital restoration approach of high-resolution transmission electron microscopy (HRTEM) images. The resulting complex exit surface wave provides information about the precise structural data of both filling material and host SWNT, establishing the SWNT's chirality and thus enabling a prediction of the composite's overall electron-transport properties.

13.
Microsc Microanal ; 11(5): 421-30, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17481323

RESUMO

The novel crystallization properties of nano-materials represent a great challenge to researchers across all disciplines of materials science. Simple binary solids can be found to adopt unprecedented structures, when confined into nanometer-sized cavities, such as the inner cylindrical bore of single-walled carbon nanotubes (SWNT). Lanthanum iodide was encapsulated within SWNTs and the resulting encapsulation composite was analyzed using energy-dispersive X-ray microanalysis (EDX) and high-resolution transmission electron microscopy (HRTEM) imaging techniques, to reveal a one-dimensional crystal fragment, with the stoichiometry of LaI2, crystallizing in the structure of LaI3 with one third of the iodine positions unoccupied. A complete characterization of the encapsulation composite was achieved using an enhanced image restoration technique, which restores the object wave from a focal series of HRTEM images, providing information about the precise structural data of both filling material and host SWNT, and thereby enabling the identification of the SWNT chirality.

14.
Nat Mater ; 2(12): 788-91, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14634642

RESUMO

Single-walled carbon nanotubes (SWNTs) can be used as templates for the growth of low-dimensional inorganic materials whose structures and properties often differ greatly from those of the bulk. Here we describe the detailed crystallography of an entire helical one-dimensional cobalt diiodide nanostructure encapsulated within a SWNT. This material has an unprecedented twisted double tetrahedral chain structure arising from a rotation of Co(2)I(4) units along its length. The complete nanostructure comprises two distinct regions with oppositely handed helices separated by a short disordered region. The encapsulating SWNT shows a commensurate ovoid distortion reflecting an unexpectedly strong interaction between the nanostructure and the SWNT.


Assuntos
Cobalto/química , Cristalização/métodos , Cristalografia/métodos , Iodetos/química , Microscopia Eletrônica de Varredura , Modelos Moleculares , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Nanotubos de Carbono/química , Simulação por Computador , Cristalização/instrumentação , Substâncias Macromoleculares , Conformação Molecular , Propriedades de Superfície
16.
J Am Chem Soc ; 124(10): 2116-7, 2002 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-11878956

RESUMO

High-resolution transmission electron microscopy and spatially resolved electron loss spectroscopy have revealed that a eutectic mixture of AgCl and AgI crystallizes within single walled carbon nanotubes (SWNTs) as metastable AgCl(1-)(x)I(x) 1D solid solution crystals. The incorporated halide crystals form wurzite "tunnel" structures with locally varying Cl:I ratios and reduced Ag coordination.

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