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1.
Nature ; 616(7955): 104-112, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36813964

RESUMEN

Blue foods, sourced in aquatic environments, are important for the economies, livelihoods, nutritional security and cultures of people in many nations. They are often nutrient rich1, generate lower emissions and impacts on land and water than many terrestrial meats2, and contribute to the health3, wellbeing and livelihoods of many rural communities4. The Blue Food Assessment recently evaluated nutritional, environmental, economic and justice dimensions of blue foods globally. Here we integrate these findings and translate them into four policy objectives to help realize the contributions that blue foods can make to national food systems around the world: ensuring supplies of critical nutrients, providing healthy alternatives to terrestrial meat, reducing dietary environmental footprints and safeguarding blue food contributions to nutrition, just economies and livelihoods under a changing climate. To account for how context-specific environmental, socio-economic and cultural aspects affect this contribution, we assess the relevance of each policy objective for individual countries, and examine associated co-benefits and trade-offs at national and international scales. We find that in many African and South American nations, facilitating consumption of culturally relevant blue food, especially among nutritionally vulnerable population segments, could address vitamin B12 and omega-3 deficiencies. Meanwhile, in many global North nations, cardiovascular disease rates and large greenhouse gas footprints from ruminant meat intake could be lowered through moderate consumption of seafood with low environmental impact. The analytical framework we provide also identifies countries with high future risk, for whom climate adaptation of blue food systems will be particularly important. Overall the framework helps decision makers to assess the blue food policy objectives most relevant to their geographies, and to compare and contrast the benefits and trade-offs associated with pursuing these objectives.


Asunto(s)
Organismos Acuáticos , Seguridad Alimentaria , Internacionalidad , Alimentos Marinos , Desarrollo Sostenible , Humanos , Dieta/métodos , Dieta/estadística & datos numéricos , Dieta/tendencias , Ambiente , Carne , Estado Nutricional , Internacionalidad/legislación & jurisprudencia , Alimentos Marinos/economía , Alimentos Marinos/estadística & datos numéricos , Alimentos Marinos/provisión & distribución , Desarrollo Sostenible/economía , Desarrollo Sostenible/legislación & jurisprudencia , Desarrollo Sostenible/tendencias , Seguridad Alimentaria/economía , Seguridad Alimentaria/legislación & jurisprudencia , Seguridad Alimentaria/métodos , Cambio Climático , Política de Salud , Política Ambiental , Factores Socioeconómicos , Características Culturales , Ácidos Grasos Omega-3 , Huella de Carbono , Enfermedades Cardiovasculares/epidemiología
2.
Nature ; 598(7880): 315-320, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34526720

RESUMEN

Despite contributing to healthy diets for billions of people, aquatic foods are often undervalued as a nutritional solution because their diversity is often reduced to the protein and energy value of a single food type ('seafood' or 'fish')1-4. Here we create a cohesive model that unites terrestrial foods with nearly 3,000 taxa of aquatic foods to understand the future impact of aquatic foods on human nutrition. We project two plausible futures to 2030: a baseline scenario with moderate growth in aquatic animal-source food (AASF) production, and a high-production scenario with a 15-million-tonne increased supply of AASFs over the business-as-usual scenario in 2030, driven largely by investment and innovation in aquaculture production. By comparing changes in AASF consumption between the scenarios, we elucidate geographic and demographic vulnerabilities and estimate health impacts from diet-related causes. Globally, we find that a high-production scenario will decrease AASF prices by 26% and increase their consumption, thereby reducing the consumption of red and processed meats that can lead to diet-related non-communicable diseases5,6 while also preventing approximately 166 million cases of inadequate micronutrient intake. This finding provides a broad evidentiary basis for policy makers and development stakeholders to capitalize on the potential of aquatic foods to reduce food and nutrition insecurity and tackle malnutrition in all its forms.


Asunto(s)
Abastecimiento de Alimentos , Internacionalidad , Alimentos Marinos/clasificación , Animales , Dieta Saludable , Femenino , Peces , Salud , Humanos , Masculino , Valor Nutritivo , Carne Roja , Alimentos Marinos/análisis , Poblaciones Vulnerables
3.
J Fish Biol ; 88(4): 1350-68, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26919062

RESUMEN

A multi-year radio-telemetry data set was used to comparatively examine the concurrent movements of the adults of three large-bodied Australian native freshwater fishes (Murray cod Maccullochella peelii, trout cod Maccullochella macquariensis and golden perch Macquaria ambigua) and the introduced carp Cyprinus carpio. The study was conducted over a reach scale in the regulated Murray River in south-eastern Australia. Differences were identified in the movements among these species. The predominant behaviour was the use of small movements (<1 km) for all species, and although larger-scale movements (>1 km) did occur, the frequency varied considerably among species. Large-scale movements were least evident for M. macquariensis and more common for M. ambigua and C. carpio with these two species also having a greater propensity to change locations. Macquaria ambigua displayed the largest movements and more M. ambigua moved on a 'continual' basis. Although a degree of site fidelity was evident for all species, the highest levels were exhibited by M. macquariensis and M. peelii. Homing was also evident to some degree in all species, but was greatest for M. peelii.


Asunto(s)
Carpas , Actividad Motora , Perciformes , Animales , Australia , Ríos , Australia del Sur , Telemetría
4.
Conserv Biol ; 28(4): 902-11, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24779578

RESUMEN

Coastal and ocean planning comprises a broad field of practice. The goals, political processes, and approaches applied to planning initiatives may vary widely. However, all planning processes ultimately require adequate information on both the biophysical and social attributes of a planning region. In coastal and ocean planning practice, there are well-established methods to assess biophysical attributes; however, less is understood about the role and assessment of social data. We conducted the first global assessment of the incorporation of social data in coastal and ocean planning. We drew on a comprehensive review of planning initiatives and a survey of coastal and ocean practitioners. There was significantly more incorporation of social data in multiuse versus conservation-oriented planning. Practitioners engaged a wide range of social data, including governance, economic, and cultural attributes of planning regions and human impacts data. Less attention was given to ecosystem services and social-ecological linkages, both of which could improve coastal and ocean planning practice. Although practitioners recognize the value of social data, little funding is devoted to its collection and incorporation in plans. Increased capacity and sophistication in acquiring critical social and ecological data for planning is necessary to develop plans for more resilient coastal and ocean ecosystems and communities. We suggest that improving social data monitoring, and in particular spatial social data, to complement biophysical data, is necessary for providing holistic information for decision-support tools and other methods. Moving beyond people as impacts to people as beneficiaries, through ecosystem services assessments, holds much potential to better incorporate the tenets of ecosystem-based management into coastal and ocean planning by providing targets for linked biodiversity conservation and human welfare outcomes.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Océanos y Mares , Biodiversidad , Conservación de los Recursos Naturales/tendencias , Recolección de Datos , Técnicas de Apoyo para la Decisión , Humanos
5.
Curr Environ Health Rep ; 10(2): 172-183, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37227626

RESUMEN

PURPOSE OF REVIEW: Aquatic foods are increasingly being recognized as a diverse, bioavailable source of nutrients, highlighting the importance of fisheries and aquaculture for human nutrition. However, studies focusing on the nutrient supply of aquatic foods often differ in the nutrients they examine, potentially biasing their contribution to nutrition security and leading to ineffective policies or management decisions. RECENT FINDINGS: We create a decision framework to effectively select nutrients in aquatic food research based on three key domains: human physiological importance, nutritional needs of the target population (demand), and nutrient availability in aquatic foods compared to other accessible dietary sources (supply). We highlight 41 nutrients that are physiologically important, exemplify the importance of aquatic foods relative to other food groups in the food system in terms of concentration per 100 g and apparent consumption, and provide future research pathways that we consider of high importance for aquatic food nutrition. Overall, our study provides a framework to select focal nutrients in aquatic food research and ensures a methodical approach to quantifying the importance of aquatic foods for nutrition security and public health.


Asunto(s)
Nutrientes , Estado Nutricional , Humanos , Dieta , Acuicultura , Explotaciones Pesqueras
6.
Acta Neurol Scand ; 126(3): 162-70, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22571291

RESUMEN

BACKGROUND: In patients with familial dysautonomia (FD), prominent orthostatic hypotension (OH) endangers cerebral perfusion. Supine repositioning or abdominal compression improves systolic and diastolic blood pressure (BPsys and BPdia). OBJECTIVE: To determine whether OH recovers faster with combined supine repositioning and abdominal compression than with supine repositioning alone. METHODS: In 9 patients with FD (17.8 ± 3.9 years) and 10 healthy controls (18.8 ± 5 years), we assessed 2-min averages of BPsys, BPdia, and heart rate (HR) during supine rest, standing, supine repositioning, another supine rest, second standing, and supine repositioning with abdominal compression by leg elevation and flexion. We determined BPsys- and BPdia-recovery-times as intervals from return to supine until BP reached values equivalent to each participant's 2-min average at supine rest minus two standard deviations. Differences in signal values and BP-recovery-times between groups and positions were assessed by ANOVA and post hoc testing (significance: P < 0.05). RESULTS: Patients with FD had pronounced OH that improved with supine repositioning. However, BP only reached supine rest values with additional abdominal compression. In controls, BP was stable during positional changes. Without abdominal compression, BP-recovery-times were longer in patients with FD than those in controls, but similar to control values with compression (BPsys: 83.7 ± 64.1 vs 36.6 ± 49.5 s; P = 0.013; BPdia: 84.6 ± 65.2 vs 35.3 ± 48.9 s; P = 0.009). CONCLUSION: Combining supine repositioning with abdominal compression significantly accelerates recovery from OH and thus lowers the risk of hypotension-induced cerebral hypoperfusion.


Asunto(s)
Disautonomía Familiar/complicaciones , Hipotensión Ortostática/etiología , Hipotensión Ortostática/rehabilitación , Esfuerzo Físico/fisiología , Recuperación de la Función , Posición Supina , Adolescente , Adulto , Análisis de Varianza , Presión Sanguínea/fisiología , Estudios de Casos y Controles , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Estadísticas no Paramétricas , Factores de Tiempo , Adulto Joven
7.
Nat Food ; 3(10): 851-861, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-37117898

RESUMEN

Injustices are prevalent in food systems, where the accumulation of vast wealth is possible for a few, yet one in ten people remain hungry. Here, for 194 countries we combine aquatic food production, distribution and consumption data with corresponding national policy documents and, drawing on theories of social justice, explore whether barriers to participation explain unequal distributions of benefits. Using Bayesian models, we find economic and political barriers are associated with lower wealth-based benefits; countries produce and consume less when wealth, formal education and voice and accountability are lacking. In contrast, social barriers are associated with lower welfare-based benefits; aquatic foods are less affordable where gender inequality is greater. Our analyses of policy documents reveal a frequent failure to address political and gender-based barriers. However, policies linked to more just food system outcomes centre principles of human rights, specify inclusive decision-making processes and identify and challenge drivers of injustice.

8.
Nat Commun ; 12(1): 5413, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34526495

RESUMEN

Numerous studies have focused on the need to expand production of 'blue foods', defined as aquatic foods captured or cultivated in marine and freshwater systems, to meet rising population- and income-driven demand. Here we analyze the roles of economic, demographic, and geographic factors and preferences in shaping blue food demand, using secondary data from FAO and The World Bank, parameters from published models, and case studies at national to sub-national scales. Our results show a weak cross-sectional relationship between per capita income and consumption globally when using an aggregate fish metric. Disaggregation by fish species group reveals distinct geographic patterns; for example, high consumption of freshwater fish in China and pelagic fish in Ghana and Peru where these fish are widely available, affordable, and traditionally eaten. We project a near doubling of global fish demand by mid-century assuming continued growth in aquaculture production and constant real prices for fish. Our study concludes that nutritional and environmental consequences of rising demand will depend on substitution among fish groups and other animal source foods in national diets.


Asunto(s)
Peces/crecimiento & desarrollo , Abastecimiento de Alimentos/estadística & datos numéricos , Alimentos , Renta/estadística & datos numéricos , Alimentos Marinos/estadística & datos numéricos , África , Animales , Acuicultura/métodos , Asia , Europa (Continente) , Abastecimiento de Alimentos/métodos , Agua Dulce , Geografía , Salud Global , Humanos , Modelos Teóricos , América del Norte , Alimentos Marinos/provisión & distribución , América del Sur
9.
J Agric Food Syst Community Dev ; 10(1): 171-189, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33996191

RESUMEN

Along the U.S. West Coast, sustainable management has rebuilt fish stocks, providing an opportunity to supply nutrient-rich food to adjacent coastal communities where food insecurity and diet-based diseases are common. However, the market has not successfully supplied locally sourced seafood to nutritionally vulnerable people. Rather, a few organizations make this connection on a limited scale. We used a "positive deviant" approach to learn how these organizations' efforts developed, how they overcame challenges, and what conditions enabled their interventions. We found that organizations in these positive deviant cases provided fish from a wide variety of species and sources, and distributed them through different channels to a diversity of end consumers. A key factor facilitating success was the ability to negotiate a price point that was both profitable and reasonable for organizations supplying nutritionally vulnerable or low-income consumers. Further-more, securing access to grants overcame initial costs of establishing new supply channels. All cases highlighted the importance of individual champions who encouraged development and cultural connections between the initiative and the nearby community. Organizations overcame key challenges by establishing regulations governing these new channels and either using partnerships or vertically integrating to reduce costs associated with processing and transport. Oftentimes training and education were also critical to instruct workers on how to process unfamiliar fish and to increase consumer awareness of local fish and how to prepare them. These lessons illuminate pathways to improve the contribution of local seafood to the healthy food system.

10.
J Fish Biol ; 75(1): 113-29, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20738486

RESUMEN

This study provides information on habitat selection by the threatened Murray cod Maccullochella peelii peelii at two spatial scales in the Ovens and Murray Rivers in south-eastern Australia. Both adult (> 450 mm total length, L(T)) and age 0 year (< 150 mm L(T)) M. p. peelii selected macro and microhabitats based on structural variables. At the macrohabitat scale, adults selected channel habitats in the river, floodplain channels at high floods and within Lake Mulwala, whereas the floodplain proper was avoided. Adult and age 0 year fish selected similar microhabitats regardless of site or hydrologic conditions, and selection was primarily influenced by the presence of higher loadings of structural woody habitat, higher c.v. in depth, more overhanging vegetation, shallower comparative depths and lower water velocities, closer to the bank. Age 0 year M. p. peelii appeared to select shallower habitats with greater amounts of structural woody habitat, closer to the river bank than adult fish.


Asunto(s)
Ecosistema , Perciformes/fisiología , Ríos , Factores de Edad , Animales
11.
Psychol Rep ; 102(2): 532-8, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18567222

RESUMEN

This study used a dual-task methodology to assess attention demands associated with error processing during an anticipation-timing task. A difference was predicted in attention demands during feedback on trials with correct responses and errors. This was addressed by requiring participants to respond to a probe reaction-time stimulus after augmented feedback presentation. 16 participants (8 men, 8 women) completed two phases, the reaction time task only and the anticipation-timing task with the probe RT task. False feedback indicating error and a financial reward manipulation were used to increase relevance of errors. Data supported the hypothesis that error processing is associated with higher cognitive demands than processing feedback denoting a correct response. Individuals responded with quicker probe reaction times during presentation of feedback on correct trials than on error trials. These results are discussed with respect to the cognitive processes which might occur during error processing and their role in motor learning.


Asunto(s)
Atención/fisiología , Cognición/fisiología , Solución de Problemas/fisiología , Desempeño Psicomotor/fisiología , Adulto , Concienciación/fisiología , Retroalimentación Psicológica/fisiología , Femenino , Lateralidad Funcional/fisiología , Humanos , MAP Quinasa Quinasa Quinasa 5 , Masculino , Memoria/fisiología , Tiempo de Reacción/fisiología , Recompensa
13.
J Mol Biol ; 301(2): 513-24, 2000 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-10926524

RESUMEN

The full three-dimensional structure of the catalytic domain of human collagenase-3 (MMP-13) complexed to a potent, sulfonamide hydroxamic acid inhibitor (CGS 27023) has been determined by NMR spectroscopy. The results reveal a core domain for the protein consisting of three alpha-helices and five beta-sheet strands with an overall tertiary fold similar to the catalytic domains of other matrix metalloproteinase family members. The S1' pocket, which is the major site of hydrophobic binding interaction, was found to be a wide cleft spanning the length of the protein and presenting facile opportunity for inhibitor extension deep into the pocket. Comparison with the reported X-ray structure of collagenase-3 showed evidence of flexibility for the loop region flanking the S1' pocket in both NMR and X-ray data. This flexibility was corroborated by NMR dynamics studies. Inhibitor binding placed the methoxy phenyl ring in the S1' pocket with the remainder of the molecule primarily solvent-exposed. The binding mode for this inhibitor was found to be similar with respect to stromelysin-1 and collagenase-1; however, subtle comparative differences in the interactions between inhibitor and enzyme were observed for the three MMPs that were consistent with their respective binding potencies.


Asunto(s)
Colagenasas/química , Inhibidores Enzimáticos/química , Ácidos Hidroxámicos/química , Metaloproteinasa 1 de la Matriz/química , Metaloproteinasa 3 de la Matriz/química , Sulfonamidas/química , Secuencia de Aminoácidos , Dominio Catalítico , Humanos , Espectroscopía de Resonancia Magnética , Metaloproteinasa 13 de la Matriz , Inhibidores de la Metaloproteinasa de la Matriz , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica
14.
Peptides ; 9(1): 173-80, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-2966343

RESUMEN

We have identified a metalloendoprotease from rat kidney cortex that cleaves the cysteine-phenylalanine bond (Cys7-Phe8) within the 17 amino acid ring structure of atrial natriuretic factor (ANF). Cleavage at this site represents the major ANF degradative activity in rat kidney, and is inhibited by the known metalloendoprotease inhibitors, thiorphan, phosphoramidon and zincov with IC50 values in the nanomolar range. Since these are specific inhibitors of protease 3.4.24.11, both protease 3.4.24.11 and ANF degrading activities were monitored during purification. Both activities copurified at each chromatographic step. Furthermore, purified protease 3.4.24.11 cleaved ANF specifically at the Cys7-Phe8 bond. It is concluded from this work that the major ANF degrading enzyme in rat kidney is protease 3.4.24.11.


Asunto(s)
Factor Natriurético Atrial/metabolismo , Corteza Renal/enzimología , Metaloendopeptidasas/aislamiento & purificación , Animales , Cromatografía de Afinidad , Cromatografía DEAE-Celulosa , Cromatografía en Gel , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Técnicas In Vitro , Masculino , Metaloendopeptidasas/metabolismo , Peso Molecular , Neprilisina , Ratas , Ratas Endogámicas
15.
Thromb Res ; 29(6): 609-17, 1983 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-6222508

RESUMEN

The balance between thrombin and plasmin action has been postulated to be an important determinant of thrombosis. Measurement of plasma concentrations of fibrinopeptide A (FPA), which reflect thrombin action on the NH2-terminal end of the A alpha chain, and of B beta 1-42 (thrombin-increasable fibrinopeptide B immunoreactivity-TIFPB) which reflect plasmin action on the NH2-terminal end of the B beta chain have shown systematic changes in the relative concentrations of the two peptides in thrombotic states. This paper reports kinetic data for TIFPB release by plasmin using fibrinogen, fibrin I monomer, and fibrin I polymer as substrates. For fibrinogen and fibrin I monomer the data fit the Michaelis-Menten equation. Experiments were performed with human proteins in 0.15M Tris-buffered saline at pH 7.4 and at 37 degrees C. With fibrinogen as substrate the Km was calculated to be 0.87 microM and the Vmax 3.75 X 10(-5) M/min/unit of plasmin. With fibrin I monomer as the substrate the Km was calculated to be 1.25 microM and the Vmax 5.5 X 10(-5) M/min/unit of plasmin. With fibrin I polymer as substrate the data did not fit the Michaelis-Menten equation but there appeared to be no dramatic differences in rates from those obtained with the other two substrates. The influence of factor XIIIa-induced cross-linking of fibrin was not examined. It is concluded from these findings that fibrinogen and non-cross-linked fibrin I are equally good substrates for plasmin cleavage of the NH2-terminal end of the B beta chain.


Asunto(s)
Productos de Degradación de Fibrina-Fibrinógeno/análisis , Fibrina/metabolismo , Fibrinógeno/metabolismo , Fibrinolisina/farmacología , Fragmentos de Péptidos , Batroxobina/farmacología , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Humanos , Cinética
16.
Thromb Res ; 26(6): 411-24, 1982 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-7112519

RESUMEN

Rapid and efficient purification methods that include hydrophobic chromatography on Phenyl Sepharose CL-4B have been developed for the peptides that span residues 241-476 (CNBr VIII), and 518-584 (CNBr X) in the A alpha chain of human fibrinogen. Amino acid analysis, NH2-terminal sequence determination, and SDS-PAGE indicated that greater than 95% purity of each peptide was achieved. Sensitive and specific radioimmunoassays capable was achieved. Sensitive and specific radioimmunoassays capable of detecting antigen in the range of 0.1-10.0 pmol/ml have also been developed for CNBr VIII and CNBr X. These assays have been characterized and successfully applied in studies designed to localize the two COOH-terminal A alpha chain regions in column effluents of CNBr-digested fibrinogen and crosslinked fibrin. When these immunoassays were used to study purified preparations of a high molecular weight, crosslink-containing CNBr derivative of a alpha polymer, the data provided immunologic confirmation for the involvement of CNBr VIII and CNBr X in alpha chain crosslinking.


Asunto(s)
Fibrina/análisis , Fibrinógeno/análisis , Secuencia de Aminoácidos , Electroforesis en Gel de Poliacrilamida , Fibrina/metabolismo , Humanos , Radioinmunoensayo
18.
J Chromatogr A ; 1217(27): 4629-38, 2010 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-20564802

RESUMEN

Nickel clad or nickel wired fused silica column bundles were constructed and evaluated. The nickel sheathing or wire functions not only as the heating element for direct resistive heat, but also as the temperature sensor, since nickel has a large resistive temperature coefficient. With this method the temperature controller is able to apply power and measure the temperature simultaneously on the same nickel element, which can effectively avoid the temperature overshoot caused by any delayed response of the sensor to the heating element. This approach also eliminates the cool spot where a separate sensor touches the column. There are some other advantages to the column bundle structure: (1) the column can be heated quickly because of the direct heating and the column's low mass, shortening analysis time. We demonstrate a maximum heating rate of 13 degrees C/s (800 degrees C/min). (2) Cooling time is also short, increasing sample throughput. The column drops from 360 degrees C to 40 degrees C is less than 1 min. (3) Power consumption is very low - 1.7 W/m (8.5 W total) for a 5 m column and 0.69 W/m (10.4 W total) for a 15 m column when they are kept at 200 degrees C isothermally. With temperature programming, the power consumption for a 5 m column is less then 70 W for an 800 degrees C/min ramp to 350 degrees C. (4) The column bundle is small, with a diameter of only about 2.25 in. All these advantages make the column bundle ideal for fast GC analysis or portable instruments. Column efficiencies and retention time repeatability have been evaluated and compared with the conventional oven heating method in this study. For isothermal conditions, the column efficiencies are measured by effective theoretical plate number. It was found that the plate number with resistive heat is always less than with oven heat, due to uneven heat in the column bundle. However, the loss is not significant - an average of about 1.5% for the nickel clad column and 4.5% for the nickel wired column. Separation numbers are used for the comparison with temperature programming, with results similar to those observed for isothermal conditions. Retention time repeatability for direct heat were 0.010% RSD for isotheral and 0.037% RSD for temperature programming, which is similar to those obtained by oven heat. Applications have been demonstrated, including diesel and PAH analysis.


Asunto(s)
Cromatografía de Gases , Níquel/química , Dióxido de Silicio/química , Cromatografía de Gases/instrumentación , Cromatografía de Gases/métodos , Gasolina , Hidrocarburos Policíclicos Aromáticos/química , Reproducibilidad de los Resultados , Temperatura
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