368 research outputs found

    Bioenergy transition as a strategic mechanism to diversify energy sources in rural areas in Colombia

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    Received: February 1st, 2023 ; Accepted: May 27th, 2023 ; Published: October 14th, 2023 ; Correspondence: [email protected], [email protected] growth in population has resulted in an increase in the consumption of goods and services, which has led to a surge in waste generation and the use of fossil fuels. To mitigate the envi-ronmental issues associated with improper waste management and reduce greenhouse gas emissions from fossil fuels, residual organic matter can be used to produce bioenergy in the form of biogas and biomethane through anaerobic digestion (AD). These biofuels can act as substitutes for liquefied petroleum gas (LPG) and natural gas (NG) and can be utilized for power and heat generation. In Colombia, the current production of biogas is 4 MW, and the government aims to increase its utilization by promoting the inclusion of biogas and biomethane in the energy matrix through a supportive regulatory framework. Studies suggest that the theoretical energy potential of livestock waste in Colombia is estimated to be 2,673 MW, but the current technological conditions allow for the utilization of only 198 MW, with the pork sector contributing 34%. This study examines the legal context and the present state of biogas in the Colombian energy matrix, while exploring the potential of the Colombian pig farming sector for biogas production. The social, economic, and environmental barriers and opportunities faced by this sector in becoming an energy producer during the transition period are also identified. The findings suggest that biogas presents a sustainable energy solution for rural areas of Colombia where pig farming is a prominent economic activity. Biogas can replace traditional fuels like LPG and firewood for cooking purposes or serve as a complementary source for electricity and thermal energy production in non-interconnected zones. This could mitigate environmental issues and reduce the prevalence of respiratory diseases associated with the use of firewood

    The Impact of Absorptive Capacity on Innovation in Peru

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    This research aims to determine absorptive capacity’s impact on innovation in SMEs in Peru. SMEs in Latin America tend to be characterized by technological backwardness, and innovations, if any, tend to be incremental in nature. In Peru, more than half of innovation activities are destined to the acquisition of capital goods. In this sense, rather than generate innovation, SMEs tend to adopt existing innovations. Thus, in order to reap the benefits of innovation adoption, SMEs must possess a high degree of absorptive capacity, understood as the firm’s capacity to value external knowledge, assimilate, and exploit it towards commercial ends. In this respect, Innovate Peru, an innovation agency, grants subsidies to SMEs for facilitating innovation adoption. In collaboration between the public and academic sector, data was recollected from 88 SMEs that were granted this innovation subsidy. This paper contributes to the literature on absorptive capacity and innovation within Latin America, which has been vaguely studied. Likewise, it holds practical implications for top managers from SMEs who are looking to innovative, and policy implications for innovation policy makers, as it validates the effect of an innovation policy instrument

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    Vesicular Glutamate Transporter 3 in age-dependent optic neuropathy

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    To determine retinal vesicular glutamate transporter 3 (VGLUT3) expression alterations in a mouse model of progressive optic neuropathy (glaucoma). Tissue specimens were obtained from age-matched DBA/2J and control C57BL/6J mice for western blot analysis. Enucleated globes from DBA/2J, C57BL/6J, and BALB/cJ mice were fixed in formalin, paraffin-embedded, and sectioned for VGLUT3 protein localization. western blot analysis of the control retinas revealed the expression of a ~55 kDa immunoreactive VGLUT3 protein that is to be expected in tissues such as retina, brain, liver, heart, and kidney tissue, but not in intestinal or lung tissue. Furthermore, a strong ~130 kDa immunoreactive VGLUT3 isoform that is restricted to the central nervous system (the brain and retinas) was also identified in the controls, but was not detected in the DBA/2J retinas. Immunofluorescence microscopy showed a lack of VGLUT3 expression in the synapses between amacrine and retinal ganglion cells in DBA/2J retinas, in contrast to its strong expression in the C57BL/6J and BALB/cJ controls. Our results implicate the dysregulated expression of a central nervous system-specific VGLUT3 isoform as a predisposing factor in the development of optic neuropathy in DBA/2J mice, a spontaneous mouse model of glaucoma. In striking parallel to the visual system defects of glaucomatous DBA/2J mice, the inner ear of VGLUT3 knockout mice displays a progressive loss of inner hair cell to spiral-ganglion neuron synapses. A significant reduction in the number of spiral-ganglion neurons leads to age-associated deafness. Thus, we propose that the absence of this biochemically uncharacterized 130 kDa VGLUT3 isoform in the DBA/2J retina is a predisposing factor in synaptic instability, and a contributing factor in the age-dependent and progressive loss of ganglion cells projecting to the brain

    Biogas production from the specialized dairy farming and porcine subsectors in Antioquia, Colombia: theoretical and technical-energy potential approach

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    Received: February 23rd, 2022 ; Accepted: May 1st, 2022 ; Published: May 11th, 2022 ; Correspondence: [email protected] developing countries, residual biomass usage by means of anaerobic digestion offers several benefits and opportunities, such as a sustainable energy source, production of organic fertilizers and new agrobusiness models. In Latin America, Colombia is one of the most promising markets for the implementation of this technology in terms of availability of biomass and economic growth, as recently reported by local government organizations. In this paper, special attention is given to Antioquia, a department of Colombia with the largest farms of cattle and pigs, according to information reported in 2018 by the Ministry of Agriculture and Rural Development. It is estimated that manure from the porcine subsector in Antioquia has an approximate technical-energy potential of 1,896 TJ year-1 , varying from 1,611 to 2,186 TJ year-1 , corresponding to the 95% confidence interval. In the case of manure generated by the livestock subsector in Antioquia, it is estimated a theoretical energy potential of 8,566 TJ year-1 . However, traditional extensive production systems disseminate manure through the pastures turning centralization of the available residual biomass a difficult task and not senseful. Based on the local practices of the specialized dairy subsector, it is estimated that manure collected during the milking process could reached up to 25% of the total available. Biochemical conversion of this amount of biomass has an estimated technical-energy potential of 187 TJ year-1 , varying from 156 and 236 TJ year-1 , corresponding to the 95% confidence. The aim of this article is to estimate the technical-energy potential for the livestock and porcine subsectors in the Department of Antioquia, based on the available residual biomass according to local farming practices

    Metritis in dairy cows: Risk factors and reproductive performance

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    The objectives of this study were to assess the risk factors for metritis, its effects on milk yield and on reproductive performance, and the efficacy of ceftiofur therapy in Holstein dairy cows. Cows (n. =. 303) from a commercial dairy herd in Argentina were studied. Cows were scored for body condition, and blood samples were collected on d -14, 7, 21, 31, 41, and 50 relative to parturition. Cows having a watery, purulent, or brown, and fetid vaginal discharge (VD) and rectal temperature ≤39.2°C were diagnosed as having clinical metritis, and those having a similar VD and rectal temperature >39.2°C were diagnosed as having puerperal metritis. Both clinical and puerperal metritis cows were randomly assigned to control (no treatment) or ceftiofur group (2.2. mg/kg. ×. 3 consecutive days). Cure was declared if clear VD was observed at 21 d in milk (DIM). Blood samples were analyzed for nonesterified fatty acids, β-hydroxybutyrate, and blood urea nitrogen using commercial kits, and for insulin-like growth factor-1, insulin, and leptin by RIA. Data were analyzed with PROC MIXED, GENMOD, PHREG, and LIFETEST from SAS (SAS Institute Inc., Cary, NC). The risk for metritis increased with dystocia, retained fetal membranes, and dead calf [AOR (adjusted odds ratio). =. 2.58, 95% CI: 1.189-5.559], and as prepartum nonesterified fatty acids levels increased (AOR. =. 1.001, 95% CI: 0.999-1.002). Conversely, risk decreased as prepartum insulin-like growth factor-1 increased (AOR. =. 0.65, 95% CI: 0.349-1.219). Cows having either clinical or puerperal metritis produced less milk by 90 DIM than did healthy cows (2,236. ±. 172 vs. 2,367. ±. 77 vs. 2,647. ±. 82 kg, respectively). Cows with puerperal metritis had lower risk for pregnancy by 100 DIM (AOR. =. 0.189, 95% CI: 0.070-0.479) and a lower hazard rate for pregnancy by 150 DIM (hazard rate: 0.753, 95% CI: 0.621-0.911), and took longer to get pregnant (129 vs. 111 vs. 109 d, for puerperal metritis, clinical metritis, and healthy cows, respectively). Ceftiofur treatment was not associated with cure rate or milk yield but was related to increased risk for pregnancy at timed artificial insemination (AOR. =. 2.688, 95% CI: 0.687-10.832), and for lower risk of reproductive cull (AOR. =. 0.121, 95% CI: 0.014-1.066). In conclusion, abnormal calving and negative energy balance are associated with increased risk for metritis. Metritis, especially puerperal metritis, correlates with reduced milk production and poor reproductive performance. Finally, the likelihood for having a normal VD (indicative of cure) increased 2.6% for every day of increase in postpartum time and was 2 times higher for cows with clinical metritis than for those with puerperal metritis.Facultad de Ciencias Veterinaria

    “Estudios de algunos fármacos coleréticos del mercado terapéutico español”

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    It is studied the choleretic activity of different natural (vegetal or animal origin) and semisynthetical drugs so that the pharmacological profile can be fixed.Se estudia la actividad colerética de diferentes fármacos de origen natural (vegetal o animal) y semisintéticos, con el fin de determinar el perfil farmacológico de los mismos
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