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1.
Sci Rep ; 13(1): 12988, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37563177

RESUMEN

The evolution of economic and innovation systems at the national scale is shaped by a complex dynamics related to the multi-layer network connecting countries to the activities in which they are proficient. Each layer represents a different domain, related to the production of knowledge and goods: scientific research, technology innovation, industrial production and trade. Nestedness, a footprint of a complex dynamics, emerges as a persistent feature across these multiple kinds of activities (i.e. network layers). We observe that, in the layers of innovation and trade, the competitiveness of countries correlates unambiguously with their diversification, while the science layer shows some peculiar features. The evolution of the scientific domain leads to an increasingly modular structure, in which the most developed countries become relatively less active in the less advanced scientific fields, where emerging countries acquire prominence. This observation is in line with a capability-based view of the evolution of economic systems, but with a slight twist. Indeed, while the accumulation of specific know-how and skills is a fundamental step towards development, resource constraints force countries to acquire competitiveness in the more complex research fields at the expense of more basic, albeit less visible (or more crowded) ones. This tendency towards a relatively specialized basket of capabilities leads to a trade-off between the need to diversify in order to evolve and the need to allocate resources efficiently. Collaborative patterns among developed countries reduce the necessity to be competitive in the less sophisticated research fields, freeing resources for the more complex ones.

2.
Struct Chang Econ Dyn ; 63: 224-240, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36518901

RESUMEN

The objective of this paper is to analyse the relationship between income inequality and environmental innovation. To this end, we use the Economic Fitness and Complexity algorithm to compute an index of green inventive capacity in a panel of 57 countries over the period 1970-2010. The empirical analysis reveals that, on average, inequality is detrimental to countries' capacity to develop complex green technologies. Using non-parametric methods we further articulate this general finding and uncover interesting non-linearities in the relationship between innovation and inequality.

3.
PLoS One ; 14(10): e0223403, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31600259

RESUMEN

We study the relationship between the performance of firms and their technological portfolios using tools borrowed from complexity science. In particular, we ask whether the accumulation of knowledge and capabilities associated with a coherent set of technologies leads firms to experience advantages in terms of productive efficiency. To this end, we analyze both the balance sheets and the patenting activity of about 70 thousand firms that have filed at least one patent over the period 2004-2013. We define a measure of corporate coherent diversification, based on the bipartite network linking companies with the technological fields in which they patent, and relate it to firm performance in terms of labor productivity. Our measure favors technological portfolios that can be decomposed into large blocks of closely related fields over portfolios with the same breadth of scope, but a more scattered diversification structure. We find that the coherent diversification of firms is quantitatively related with their economic performance and captures relevant information about their productive structure. In particular, we prove on a statistical basis that a naive definition of technological diversification can explain labor productivity only as a proxy of size and coherent diversification. This approach can be used to investigate possible synergies within firms and to recommend viable partners for mergers and acquisitions.


Asunto(s)
Organizaciones , Tecnología , Patentes como Asunto , Estadística como Asunto
4.
R Soc Open Sci ; 5(6): 172445, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30110482

RESUMEN

We analyse the autocatalytic structure of technological networks and evaluate its significance for the dynamics of innovation patenting. To this aim, we define a directed network of technological fields based on the International Patents Classification, in which a source node is connected to a receiver node via a link if patenting activity in the source field anticipates patents in the receiver field in the same region more frequently than we would expect at random. We show that the evolution of the technology network is compatible with the presence of a growing autocatalytic structure, i.e. a portion of the network in which technological fields mutually benefit from being connected to one another. We further show that technological fields in the core of the autocatalytic set display greater fitness, i.e. they tend to appear in a greater number of patents, thus suggesting the presence of positive spillovers as well as positive reinforcement. Finally, we observe that core shifts take place whereby different groups of technology fields alternate within the autocatalytic structure; this points to the importance of recombinant innovation taking place between close as well as distant fields of the hierarchical classification of technological fields.

5.
Entropy (Basel) ; 20(10)2018 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-33265864

RESUMEN

The present study provides an analysis of empirical regularities in the development of green technology. We use patent data to examine inventions that can be traced to the environment-related catalogue (ENV-Tech) covering technologies in environmental management, water-related adaptation and climate change mitigation. Furthermore, we employ the Economic Fitness-Complexity (EFC) approach to assess their development and geographical distribution across countries between 1970 and 2010. This allows us to identify three typologies of countries: leaders, laggards and catch-up. While, as expected, there is a direct relationship between GDP per capita and invention capacity, we also document the remarkable growth of East Asia countries that started from the periphery and rapidly established themselves as key actors. This geographical pattern coincides with higher integration across domains so that, while the relative development of individual areas may have peaked, there is now demand for greater interoperability across green technologies.

6.
J Sci Food Agric ; 98(6): 2370-2377, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28994453

RESUMEN

BACKGROUND: The sale of raw drinking milk through automatic dispensers is permitted in some EU member states, but consumers are usually advised to boil the milk before consumption. The present study has been conducted to evaluate the effects of two common domestic boiling techniques on the proteins of raw milk and, in particular, on their potential allergenicity. RESULTS: Native one-dimensional electrophoresis, N-terminal amino acid sequencing and immunoblotting have been used to characterize the protein pattern and to evaluate the possible changes in the allergenic properties of the processed milk. The main result of this investigation is that heating induces the aggregation of ß-lactoglobulin in higher-molecular-weight products, while caseins seem to be more resistant to the treatments. ß-Lactoglobulin aggregates have been found to be non-immunoreactive with the sera of subjects suffering from cow's milk protein allergy. CONCLUSION: Domestic boiling modifies the milk protein profile, causing a minor reduction in milk allergenicity. © 2017 Society of Chemical Industry.


Asunto(s)
Culinaria/métodos , Leche/química , Animales , Animales Domésticos , Bovinos , Femenino , Calor , Immunoblotting , Leche/inmunología , Proteínas de la Leche/química , Proteínas de la Leche/inmunología
7.
J Biol Chem ; 290(19): 12403-14, 2015 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-25814665

RESUMEN

Human rotavirus is the leading cause of severe gastroenteritis in infants and children under the age of 5 years in both developed and developing countries. Human lactadherin, a milk fat globule membrane glycoprotein, inhibits human rotavirus infection in vitro, whereas bovine lactadherin is not active. Moreover, it protects breastfed infants against symptomatic rotavirus infections. To explore the potential antiviral activity of lactadherin sourced by equines, we undertook a proteomic analysis of milk fat globule membrane proteins from donkey milk and elucidated its amino acid sequence. Alignment of the human, bovine, and donkey lactadherin sequences revealed the presence of an Asp-Gly-Glu (DGE) α2ß1 integrin-binding motif in the N-terminal domain of donkey sequence only. Because integrin α2ß1 plays a critical role during early steps of rotavirus host cell adhesion, we tested a minilibrary of donkey lactadherin-derived peptides containing DGE sequence for anti-rotavirus activity. A 20-amino acid peptide containing both DGE and RGD motifs (named pDGE-RGD) showed the greatest activity, and its mechanism of antiviral action was characterized; pDGE-RGD binds to integrin α2ß1 by means of the DGE motif and inhibits rotavirus attachment to the cell surface. These findings suggest the potential anti-rotavirus activity of equine lactadherin and support the feasibility of developing an anti-rotavirus peptide that acts by hindering virus-receptor binding.


Asunto(s)
Antígenos de Superficie/química , Glucolípidos/química , Glicoproteínas/química , Glicoproteínas de Membrana/química , Proteínas de la Leche/química , Péptidos/química , Infecciones por Rotavirus/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Bovinos , Membrana Celular/metabolismo , Supervivencia Celular , Equidae , Caballos , Humanos , Concentración 50 Inhibidora , Integrinas/química , Gotas Lipídicas , Leche , Datos de Secuencia Molecular , Proteómica , Rotavirus/metabolismo , Infecciones por Rotavirus/tratamiento farmacológico , Homología de Secuencia de Aminoácido , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
8.
Plant Physiol Biochem ; 49(4): 395-403, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21345687

RESUMEN

A cationic soluble peroxidase isoenzyme (CysPrx) has been purified and characterized from artichoke (Cynara cardunculus subsp. scolymus (L.) Hegi) leaves by combination of aqueous two phase extraction, ion exchange chromatography, and gel filtration. The purification fold was 149 and the activity recovery 5.5%. CysPrx was stable from 5 to 45 °C with a pH optimum around 5.5; the pI was 8.3 and the MW of 37.7 ± 1.5 kDa. MALDI-TOF MS analysis provided partial peptide sequences and resolved CysPrx isoenzyme into two putative isoforms. The presence of these isoforms was confirmed by the isolation of full-length cDNA encoding CysPrx that generate two slightly different sequences coding for two putative CysPrx: CysPrx1 and CysPrx2. The obtained MS peptides showed a 35% coverage with 100% identity with the two CysPrx deduced protein sequences. A molecular modeling analysis was carried out to predict in silico the protein structure and compare it with other plant Prx structures. Considering that CysPrx is quite stable, the study carried out in this paper will offer new insights for the production of the recombinant protein for utilization of CysPrx as an alternative Prx for food technology, biomedical analysis and bioremediation.


Asunto(s)
Cynara scolymus/enzimología , Péptidos/análisis , Peroxidasas/aislamiento & purificación , Hojas de la Planta/enzimología , Proteínas de Plantas/aislamiento & purificación , Secuencia de Aminoácidos , Clonación Molecular , Cynara scolymus/química , Cynara scolymus/genética , ADN Complementario/aislamiento & purificación , Concentración de Iones de Hidrógeno , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/aislamiento & purificación , Modelos Moleculares , Datos de Secuencia Molecular , Estructura Molecular , Peroxidasas/química , Peroxidasas/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
9.
Proteomics ; 5(1): 282-9, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15593144

RESUMEN

Birch pollen-related food allergies are mainly associated to Bet v 1. Little is known about isoforms of Bet v 1 homologous in fruit of the Rosaceae family. We attempted to identify novel isoforms of Pru av 1, the major cherry allergen, at the cDNA and the protein level by a combination of molecular biology and proteomic tools. A cDNA library was screened with patients immunoglobulin E (IgE) and a specific hybridization probe. Edman sequencing, mass spectrometry (MS), and MS/MS were performed after detecting Pru av 1 on 2-D maps by immunoblotting using patients IgE and a monoclonal antibody. Partial amino acid sequences were completed with a polymerase chain reaction (PCR) strategy. The IgE-binding properties of the Pru av 1 spots were analyzed by 2-D blot inhibition. cDNA library analysis revealed a novel Pru av 1 isoform. MS and N-terminal sequencing confirmed the cDNA sequences at the protein level. A series of spots were confirmed as the already known Pru av 1. One spot, exclusively detected with patients sera, was identified as the novel isoform. A partial amino acid sequence detected with MS/MS was completed by PCR-cloning. The 2-D blot inhibition revealed epitope differences between the novel isoform and the previously published Pru av 1. Our data demonstrate that a synergistic combination of molecular biology and proteomics represents a powerful tool for reliable and comprehensive identification of allergen isoforms and variants. The newly identified isoform showed diverging IgE-binding properties and may be relevant for the diagnosis or therapy of cherry allergy.


Asunto(s)
Alérgenos/metabolismo , Inmunoglobulina E/metabolismo , Proteínas de Plantas/metabolismo , Rosaceae/inmunología , Alérgenos/genética , Secuencia de Aminoácidos , Electroforesis en Gel Bidimensional , Biblioteca de Genes , Humanos , Inmunoglobulina E/genética , Datos de Secuencia Molecular , Biblioteca de Péptidos , Proteínas de Plantas/genética , Polen , Reacción en Cadena de la Polimerasa , Unión Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteómica , Rosaceae/genética , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
10.
Proteomics ; 3(6): 897-905, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12833513

RESUMEN

Milk fat globule membrane (MFGM) contains proteins derived from the apical membrane of secreting epithelial cells of the mammary gland. Between 2-4% of total human milk protein content is associated with the fat globule fraction, as MFGM proteins. While MFGM proteins have very low classical nutritional value, they play important roles in various cell processes and defence mechanisms for the newborn. To date, fewer than 30 human MFGM proteins have been identified and characterized, either by immunological methods or by Edman sequencing and mass spectrometry. This study aimed to update the structural proteome of human colostral MFGM proteins and to create an annotated two-dimensional electrophoresis (2-DE) MFGM protein database available on-line. More than one hundred 2-DE spots derived from human colostral MFGM proteins were investigated by matrix-assisted laser desorption/ionization-time of flight mass spectrometry and proteins were identified by three different software packages available on the web (PeptIdent, MS-Fit and ProFound); uncertain identifications were solved by nanoelectrospray ionization-ion trap mass spectrometry using SEQUEST software.


Asunto(s)
Proteínas de la Membrana/análisis , Proteínas de la Leche/análisis , Leche Humana/química , Proteoma/análisis , Bases de Datos de Proteínas , Femenino , Humanos , Internet , Proteínas de la Membrana/clasificación , Proteínas de la Membrana/aislamiento & purificación , Programas Informáticos , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
11.
Proteomics ; 2(7): 850-6, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12124930

RESUMEN

Human butyrophilin (BTN) expression in milk fat globule (MFGM) was evaluated using two dimensional electrophoresis (2-DE) as the separation technique, and peptide mass mapping by matrix-assisted laser desorption/ionisation-mass spectrometry (MALDI-MS) as the identification tool. Since milk composition changes throughout lactation time, 2-DE maps in the pH range 4-7 of colostral MFGM and mature MFGM were compared, showing only slight differences in BTN spot distribution. The BTN gene family codes for seven proteins (BTN, BTN2A1, BTN2A2, BTN2A3, BTN3A1, BTN3A2, BTN3A3), their presence in human tissues has to date been evaluated only at a transcriptional level. Among 70 spots, analyzed and identified by MALDI-MS, 13 spots were identified as BTN spots and only one as a fragment of BTN2A1. BTN was present in multiple glycoforms, and two smaller BTN forms of about 45 kDa were also identified. We propose an array of BTNs on human MFGM, which could provide breast-fed infants with immune molecules during the neonatal period.


Asunto(s)
Grasas/química , Membranas Intracelulares/química , Glicoproteínas de Membrana/genética , Leche Humana/química , Proteómica , Secuencia de Aminoácidos , Animales , Butirofilinas , Vesículas Citoplasmáticas/química , Vesículas Citoplasmáticas/metabolismo , Electroforesis en Gel Bidimensional , Femenino , Humanos , Membranas Intracelulares/metabolismo , Espectrometría de Masas , Datos de Secuencia Molecular , Familia de Multigenes , Alineación de Secuencia
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