657 research outputs found
La competitividad en una empresa forestal comunitaria
Forest utilization plays a fundamental role for the supply of raw material to the forest industry and the socio-economic development of forest communities, given its natural potential in providing goods and services. There are several studies of forest management, but few on competitiveness of productive chains. The present investigation was carried out in the forest community of Capulalpam de Méndez, Ixtlán, Oaxaca, Mexico and is considered a non-experimental design because the phenomenon was observed as it occurs in its natural context, to later analyze it without manipulating variables The results obtained show that the indicators: Productivity, product quality, profitability and market share, with values of 0.75, 0.75, 0.70 and 0.62 respectively, are the most important indicators that determine the achievement of the company's competitiveness.El aprovechamiento forestal desempeña un papel fundamental para el abastecimiento de materia prima a la industria forestal y al desarrollo socioeconómico de las comunidades forestales, dado su potencial natural en proporcionar bienes y servicios. Existen diversos estudios del manejo forestal, pero, pocos sobre competitividad de las cadenas productivas. La presente investigación se llevó a cabo en la comunidad forestal de Capulalpam de Méndez, Ixtlán, Oaxaca, México y se considera un diseño no experimental debido a que se observó el fenómeno tal y como se da en su contexto natural, para posteriormente analizarlo sin manipular variables. Los resultados obtenidos muestran que los indicadores: Productividad, calidad del producto, rentabilidad y participación en el mercado, con valores de 0.75, 0.75, 0.70 y 0.62 respectivamente, son los indicadores más importantes que determinan el logro de la competitividad de la empresa
Late left ventricular dysfunction after anatomic repair of congenitally corrected transposition of the great arteries
ObjectiveEarly results for anatomic repair of congenitally corrected transposition of the great arteries (ccTGA) are excellent. However, the development of left ventricular dysfunction late after repair remains a concern. In this study we sought to determine factors leading to late left ventricular dysfunction and the impact of cardiac resynchronization as a primary and secondary (upgrade) mode of pacing.MethodsFrom 1992 to 2012, 106 patients (median age at surgery, 1.2 years; range, 2 months to 43 years) with ccTGA had anatomic repair. A retrospective review of preoperative variables, surgical procedures, and postoperative outcomes was performed.ResultsIn-hospital deaths occurred in 5.7% (n = 6), and there were 3 postdischarge deaths during a mean follow-up period of 5.2 years (range, 7 days to 18.2 years). Twelve patients (12%) developed moderate or severe left ventricular dysfunction. Thirty-eight patients (38%) were being paced at latest follow-up evaluation. Seventeen patients had resynchronization therapy, 9 as an upgrade from a prior dual-chamber system (8.5%) and 8 as a primary pacemaker (7.5%). Factors associated with left ventricular dysfunction were age at repair older than 10 years, weight greater than 20 kg, pacemaker implantation, and severe neo-aortic regurgitation. Eight of 9 patients undergoing secondary cardiac resynchronization therapy (upgrade) improved left ventricular function. None of the 8 patients undergoing primary resynchronization developed left ventricular dysfunction.ConclusionsLate left ventricular dysfunction after anatomic repair of ccTGA is not uncommon, occurring most often in older patients and in those requiring pacing. Early anatomic repair and cardiac resynchronization therapy in patients requiring a pacemaker could preclude the development of left ventricular dysfunction
Mechanisms of tricuspid regurgitation in patients with hypoplastic left heart syndrome undergoing tricuspid valvuloplasty
ObjectivesTricuspid regurgitation (TR) remains a risk factor for morbidity and mortality through staged palliation in patients with hypoplastic left heart syndrome (HLHS). Reports on the mechanisms associated with TR in patients with HLHS are limited. Thus, we sought to describe our experience with tricuspid valve (TV) repair in these patients, focusing on the mechanisms of TR and corresponding surgical techniques.MethodsWe performed a retrospective single-center review (January 2000 to December 2012) of patients with HLHS undergoing TV repair and completing Fontan circulation. We evaluated the pre- and postoperative echocardiograms, intraoperative findings, and surgical techniques used.ResultsA total of 53 TV repairs were performed in 35 patients with HLHS completing staged palliation. TV repairs were performed at stage II in 15, between stage II and III in 4, at stage III in 27, and after stage III in 7. The surgical techniques for valvuloplasty included annuloplasty (38%), anteroseptal (AS) commissuroplasty (66%), anterior papillary muscle repositioning (11%), multiple commissuroplasties (9%), septal-posterior commissuroplasty (9%), and fenestration closure (4%). The predominant jet of TR emanated along the AS commissure in 68% of the cases. All patients survived the procedure and were discharged. Preoperative echocardiography showed a dilated TV annulus on the lateral dimension, anteroposterior dimension, and area that was significantly reduced after TV repair (P < .0001). The preoperative mean TR, as assessed by lateral (P = .002) and anteroposterior (P = .005) vena contracta, was also significantly reduced after TV repair. TV repair did not significantly affect right ventricular systolic function immediately after surgery (P = .17) or at the most recent follow-up visit (P = .52). Patients with anterior leaflet prolapse were at increased risk of worse outcomes, including moderate or greater right ventricular dysfunction (P = .02). Patients requiring reoperation for TV repair were younger (6.3 vs 28.1 months, P < .0001) at the initial operation. One patient died of heart failure. Freedom from TV replacement and transplant-free survival were both 97% at the most recent follow-up point.ConclusionsTR in patients with HLHS commonly emanates from the AS commissure. The associated mechanisms are often annular dilatation and anterior leaflet prolapse. Preoperative anterior leaflet prolapse was associated with worse outcomes. Annuloplasty, closure of the AS commissure, and repositioning of the anterior papillary muscle are effective in addressing TR in the short- and mid-term in this challenging population
Surgical repair of truncal valve regurgitation†
OBJECTIVES Truncal valve regurgitation remains a short- and long-term risk factor for patients with truncus arteriosus. There are limited data available on techniques and outcomes of truncal valve repair (TVR). The aim of this study was to report our experience with TVR in patients of all ages. METHODS From 1997 to 2012, 36 patients (13 neonates, 30 children and 3 adults) underwent TVR for significant regurgitation. RESULTS There were 3 early deaths (8%), all of which were in neonates. Twenty-two patients had a quadricuspid, 13 a tricuspid and 1 a bicuspid truncal valve before repair. Valve repair improved regurgitation in 31 of 36 repairs. The median regurgitation decreased from moderate-severe to mild (P < 0.001). During a mean follow-up of 38.3 ± 44.9 months (range 1 month—15 years), there was 1 late death, 16 patients required reoperation on the truncal valve and 1 required a second reoperation. Freedom from reoperation was 91.4 ± 4.8% at 1 year, 55.0 ± 10.4% at 5 and 22.9 ± 12.2% at 10 years. A quadricuspid valve after repair tended to worsen freedom from reoperation (P = 0.15), and tricuspidization tended to improve freedom from reoperation (P = 0.19). Neonatal repair (hazards ratio (HR) 4.1, P = 0.03) and leaflet thinning (HR 22.5, P = 0.002) were independent predictors of reoperation. CONCLUSIONS Valve repair for truncal valve regurgitation is feasible, with good results. Surgical creation of a tricuspid truncal valve seems to provide the best outcomes in this challenging populatio
Algunas evidencias de aplicación
Libro temático especializadoLa sustentabilidad también debe aplicarse al sistema de producción, buscando impulsar transformaciones graduales de los estilos y modelos productivos tradicionales a unas de mayor eficiencia. Y donde se incorpore la dimensión ambiental y geográfico-espacial, para crear estructuras productivas más progresivas y equitativas en las sociedades. Todo esto, como alternativa para revertir las tendencias de escasez y agotamiento de los recursos naturales, así como de los desequilibrios globales, cuyos costos permean todos los tejidos humanos. De esta manera, la “sustentabilidad productiva” se concibe como la generación de bienes y servicios con ciertos estándares de calidad, bajo un esquema de eficiencia, rendimiento y de organización inclusiva e integrada, con baja presión al ambiente y uso racional de los recursos, garantizando la estadía y permanencia de los insumos y materiales en el tiempo. Desde esta perspectiva, la producción sustentable y el crecimiento de largo plazo pueden ser explicados por la capacidad que tienen las economías para generar e incorporar conocimientos y tecnologías. De ahí que, la educación y las cualificaciones del capital humano, los cambios en la organización de la producción y la calidad institucional, sean elementos nodales para avanzar en la consolidación de este ambiente productivo
A Novel Small Molecule Inhibitor of Influenza A Viruses that Targets Polymerase Function and Indirectly Induces Interferon
Influenza viruses continue to pose a major public health threat worldwide and options for antiviral therapy are limited by the emergence of drug-resistant virus strains. The antiviral cytokine, interferon (IFN) is an essential mediator of the innate immune response and influenza viruses, like many viruses, have evolved strategies to evade this response, resulting in increased replication and enhanced pathogenicity. A cell-based assay that monitors IFN production was developed and applied in a high-throughput compound screen to identify molecules that restore the IFN response to influenza virus infected cells. We report the identification of compound ASN2, which induces IFN only in the presence of influenza virus infection. ASN2 preferentially inhibits the growth of influenza A viruses, including the 1918 H1N1, 1968 H3N2 and 2009 H1N1 pandemic strains and avian H5N1 virus. In vivo, ASN2 partially protects mice challenged with a lethal dose of influenza A virus. Surprisingly, we found that the antiviral activity of ASN2 is not dependent on IFN production and signaling. Rather, its IFN-inducing property appears to be an indirect effect resulting from ASN2-mediated inhibition of viral polymerase function, and subsequent loss of the expression of the viral IFN antagonist, NS1. Moreover, we identified a single amino acid mutation at position 499 of the influenza virus PB1 protein that confers resistance to ASN2, suggesting that PB1 is the direct target. This two-pronged antiviral mechanism, consisting of direct inhibition of virus replication and simultaneous activation of the host innate immune response, is a unique property not previously described for any single antiviral molecule
Type 2 Diabetes Variants Disrupt Function of SLC16A11 through Two Distinct Mechanisms
Type 2 diabetes (T2D) affects Latinos at twice the rate seen in populations of European descent. We recently identified a risk haplotype spanning SLC16A11 that explains ∼20% of the increased T2D prevalence in Mexico. Here, through genetic fine-mapping, we define a set of tightly linked variants likely to contain the causal allele(s). We show that variants on the T2D-associated haplotype have two distinct effects: (1) decreasing SLC16A11 expression in liver and (2) disrupting a key interaction with basigin, thereby reducing cell-surface localization. Both independent mechanisms reduce SLC16A11 function and suggest SLC16A11 is the causal gene at this locus. To gain insight into how SLC16A11 disruption impacts T2D risk, we demonstrate that SLC16A11 is a proton-coupled monocarboxylate transporter and that genetic perturbation of SLC16A11 induces changes in fatty acid and lipid metabolism that are associated with increased T2D risk. Our findings suggest that increasing SLC16A11 function could be therapeutically beneficial for T2D. Video Abstract [Figure presented] Keywords: type 2 diabetes (T2D); genetics; disease mechanism; SLC16A11; MCT11; solute carrier (SLC); monocarboxylates; fatty acid metabolism; lipid metabolism; precision medicin
The 13th Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey Mapping Nearby Galaxies at Apache Point Observatory
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in July 2014. It pursues three core programs: APOGEE-2,MaNGA, and eBOSS. In addition, eBOSS contains two major subprograms: TDSS and SPIDERS. This paper describes the first data release from SDSS-IV, Data Release 13 (DR13), which contains new data, reanalysis of existing data sets and, like all SDSS data releases, is inclusive of previously released data. DR13 makes publicly available 1390 spatially resolved integral field unit observations of nearby galaxies from MaNGA,the first data released from this survey. It includes new observations from eBOSS, completing SEQUELS. In addition to targeting galaxies and quasars, SEQUELS also targeted variability-selected objects from TDSS and X-ray selected objects from SPIDERS. DR13 includes new reductions ofthe SDSS-III BOSS data, improving the spectrophotometric calibration and redshift classification. DR13 releases new reductions of the APOGEE-1data from SDSS-III, with abundances of elements not previously included and improved stellar parameters for dwarf stars and cooler stars. For the SDSS imaging data, DR13 provides new, more robust and precise photometric calibrations. Several value-added catalogs are being released in tandem with DR13, in particular target catalogs relevant for eBOSS, TDSS, and SPIDERS, and an updated red-clump catalog for APOGEE.This paper describes the location and format of the data now publicly available, as well as providing references to the important technical papers that describe the targeting, observing, and data reduction. The SDSS website, http://www.sdss.org, provides links to the data, tutorials and examples of data access, and extensive documentation of the reduction and analysis procedures. DR13 is the first of a scheduled set that will contain new data and analyses from the planned ~6-year operations of SDSS-IV.PostprintPeer reviewe
The 16th Data Release of the Sloan Digital Sky Surveys : First Release from the APOGEE-2 Southern Survey and Full Release of eBOSS Spectra
This paper documents the 16th data release (DR16) from the Sloan Digital Sky Surveys (SDSS), the fourth and penultimate from the fourth phase (SDSS-IV). This is the first release of data from the Southern Hemisphere survey of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2); new data from APOGEE-2 North are also included. DR16 is also notable as the final data release for the main cosmological program of the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), and all raw and reduced spectra from that project are released here. DR16 also includes all the data from the Time Domain Spectroscopic Survey and new data from the SPectroscopic IDentification of ERosita Survey programs, both of which were co-observed on eBOSS plates. DR16 has no new data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey (or the MaNGA Stellar Library "MaStar"). We also preview future SDSS-V operations (due to start in 2020), and summarize plans for the final SDSS-IV data release (DR17).Peer reviewe
- …