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2.
NanoImpact ; 28: 100432, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36220628

RESUMO

This paper gathers gatekeeper views and perceptions on nano-enabled viticulture in Aotearoa New Zealand. While the science of nanotechnology is indicated to offer improvements to conventional vineyard inputs and operations, its acceptability by potential users and consumers has an impact on the governance of nano-enabled agriculture. This governance takes place not just at the state level through regulation and policy, but also through corporate, and community sectors' use of branding and narratives about nanotechnology and nano-based agrichemicals, and the (non)consumption of nano-enabled products. This paper investigates the technical and market acceptability, or governance, of nanotechnology by elucidating the attitudes of industry gatekeepers towards wines grown with nanotechnology. This necessarily informs the 'market permissibility' of such technologies, and illuminates sensitivities, concerns, and consumer-based barriers to adoption. We conducted 15 semi-structured, key informant interviews and a thematic data analysis. Our results suggest a high level of technical acceptability, particularly if environmental sustainability benefits are made clear. Wine producers are interested in nano-solutions to labour, pest and disease, and cost of production issues. However, key actors in the production-consumption network of New Zealand wine have concerns about nano-enabled approaches. Regulatory approval and safety assurances are expected prior to adoption in food or wine. Respondents argue that consumer acceptability is less clear, and that thought leaders like wine writers, intermediaries and 'influencers' will be critical in shaping public opinion. This research highlights the potential risks of nanotechnology development and adoption.


Assuntos
Nanotecnologia , Políticas , Nova Zelândia , Análise de Dados , Opinião Pública
3.
J Gen Virol ; 88(Pt 9): 2450-2462, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17698654

RESUMO

Equid herpesvirus 2 (EHV-2), in common with other members of the subfamily Gammaherpesvirinae, encodes homologues of cellular seven-transmembrane receptors (7TMR), namely open reading frames (ORFs) E1, 74 and E6, which each show some similarity to cellular chemokine receptors. Whereas ORF74 and E6 are members of gammaherpesvirus-conserved 7TMR gene families, E1 is currently unique to EHV-2. To investigate their genetic variability, EHV-2 7TMRs from a panel of equine gammaherpesvirus isolates were sequenced. A region of gB was sequenced to provide comparative sequence data. Phylogenetic analysis revealed six 'genogroups' for E1 and four for ORF74, which exhibited approximately 10-38 and 11-27 % amino acid difference between groups, respectively. In contrast, E6 was highly conserved, with two genogroups identified. The greatest variation was observed within the N-terminal domains and other extracellular regions. Nevertheless, analysis of the number of non-synonymous (d(N)) and synonymous (d(S)) substitutions per site generally supported the hypothesis that the 7TMRs are under negative selective pressure to retain functionally important residues, although some site-specific positive selection (d(N)>d(S)) was also observed. Collectively, these data are consistent with transmembrane and cytoplasmic domains being less tolerant of mutations with adverse effects upon function. Finally, there was no evidence for genetic linkage between the different gB, E1, ORF74 and E6 genotypes, suggesting frequent intergenic recombination between different EHV-2 strains.


Assuntos
Fases de Leitura Aberta , Receptores de Quimiocinas/genética , Rhadinovirus/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Animais , Técnicas de Cultura de Células , Sequência Conservada , Primers do DNA , DNA Viral/genética , DNA Viral/isolamento & purificação , Variação Genética , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Rhadinovirus/classificação , Rhadinovirus/isolamento & purificação , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Proteínas Virais/química
4.
Inorg Chem ; 46(18): 7232-4, 2007 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-17691724

RESUMO

A series of alkynylchalcogenophene platinum(II) complexes have been synthesized and characterized by multinuclear NMR and UV-visible absorption spectroscopies; the NMR spectra show unprecedented long-range heteronuclear coupling, and clear correlations emerge between spectroscopic data and theoretical analysis of their electronic structures.

5.
Environ Sci Technol ; 40(12): 3934-40, 2006 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-16830564

RESUMO

The physical properties of natural organic matter (NOM) flocs, such as size, growth rate, and strength, were investigated using a laser diffraction particle sizing device. Conditions were set such that varying carbon coagulant ratio and zeta potential could both be investigated. Results demonstrated a link between zeta potential and coagulation and flocculation performance, with the production of strong flocs and low residual concentrations when the zeta potential was minimized. The overall strength of the connection points within the floc were determined by a combination of steric interactions, polymer bridging, van der Waals forces, and electrostatic forces. Hence, both dose ratio and zeta potential are important in understanding floc properties. Floc growth was dominated by dose ratio, whereas the response to elevated shear was strongly related to zeta potential. The steady-state floc size was a combination of both factors. This allowed the continued development of a qualitative model in order to engineer optimal floc properties when coagulating NOM.


Assuntos
Compostos Férricos/química , Compostos Orgânicos/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Floculação , Tamanho da Partícula
6.
Environ Pollut ; 140(3): 436-43, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16181714

RESUMO

Natural organic matter (NOM) is one of the main sources of environmental pollution to drinking water supplies in much of the UK and the US. Whilst traditional treatment with trivalent coagulants has proven a successful strategy in the past, operational problems are now being reported during periods of elevated organic levels in the water. Characterisation of the pollutants in terms of polarity, molecular weight and charge, provides a method to understand the impact of the observed temporal and spatial variations in terms of a mechanistic parameter relevant to the treatment processes. Results from this study demonstrate that it is not simply the increased organic concentration, but also the change in NOM composition and character, which influences the impact on the treatment processes. Consequently, monitoring of these parameters provides an insight into how to manage the impact caused by environmental changes to the catchments.


Assuntos
Compostos de Alumínio/química , Alumínio/química , Carbono/análise , Compostos Férricos/química , Estações do Ano , Monitoramento Ambiental/métodos , Substâncias Húmicas/análise , Concentração de Íons de Hidrogênio , Ponto Isoelétrico , Microbiologia do Solo , Poluentes da Água/análise , Purificação da Água/normas
7.
Sci Total Environ ; 363(1-3): 183-94, 2006 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15987654

RESUMO

In the past decade, a number of UK and US water utilities have been experiencing operational difficulties connected with the increased dissolved organic carbon (DOC) levels during the autumn and winter periods. This has been observed as an increase in the production of disinfection-by-products (DBP), and a greater coagulant demand. Resin adsorption techniques were used to fractionate raw water and investigate the variation in surface charge and coagulant-humic interactions over a 36-month period. A change in the natural organic matter (NOM) composition throughout the year was observed, with the fulvic acid fraction (FAF) increasing from 36% in September to 61% in November. However, a reduction in treatment performance is not simply due to an increase in DOC concentrations (from 4.3 to 14.5 mg L-1), but also a change in the charge density of the NOM. It was found that hydrophilic NOM fractions possess negligible charge density (<0.06 meq g-1DOC), and it is the hydrophobic NOM fractions, FAF in particular, that exert the greater dominance on coagulation control. The hydrophilic NOM fractions are less amenable to removal through conventional coagulation with metal salts, and are therefore likely to indicate the DOC residual remaining after treatment. Understanding the seasonal changes in NOM composition and character and their reactivity with coagulants should lead to a better optimisation of the coagulation process and a more consistent water quality.

8.
Bioorg Med Chem Lett ; 12(14): 1845-8, 2002 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-12086831

RESUMO

A range of di- and tri-substituted triazenes have been synthesized from a polymer-supported diazonium salt and various primary and secondary amines. The triazenes obtained were treated with transition metal salts to form polymer-supported metal complexes in firstly a general screen and then in a specific manner.


Assuntos
Paládio/química , Polímeros/química , Rutênio/química , Triazenos/química , Aminas/química , Catálise , Química Orgânica/métodos , Técnicas de Química Combinatória , Compostos de Diazônio/química , Ligantes , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Triazenos/síntese química
9.
Bioorg Med Chem Lett ; 12(14): 1849-51, 2002 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-12086832

RESUMO

A range of polymer-supported triazenes and their metal-bound analogues were screened for use in catalysis. Fe, Cu and Zr complexes were, together with the polymer-supported triazene ligand alone, screened in the addition of Et(2)Zn to benzaldehyde. A supported Pd triazene complex was screened for activity in Suzuki and Sonogashira reactions and a supported Ru triazene complex screened for transfer hydrogenation.


Assuntos
Compostos Organometálicos/química , Polímeros/química , Triazenos/química , Aminas/química , Benzaldeídos/química , Catálise , Química Orgânica/métodos , Compostos de Diazônio/química , Hidrogenação , Indicadores e Reagentes , Ligantes , Metais Pesados/química , Estereoisomerismo , Triazenos/síntese química
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