Effect of Refractance Window™ and oven drying on physicochemical and sensory properties of peach (Prunus persica L.) surplus.

Currently, approximately 34% of fruit is lost and wasted in emerging economies due to inefficient post-harvest processes, technological shortcomings, lesser valorization of surpluses, and byproducts. Peach (Prunus persica L.) is a fruit with a good yearly growth rate but higher postharvest losses in Colombia. One way to take advantage of this type of product is through the application of drying processes that increase its shelf life and its inclusion in the food chain. Refractance Window Drying (RWD) is a fourth generation drying technique implemented by the food industry in the last few decades and has been applied to several dehydrated food products. This study compared the effects of different drying methods on the physical and sensory properties of peaches surplus. Treatments consisted of (i) peaches were sliced (1, 2, and 3 mm thickness) and dried using RWD at 86°C, (ii) peach pulp mixed with maltodextrin (MD) (0.12-0.33 kg of MD/kg of sample) and RWD (RWD-MD), and (iii) conventional oven drying (OD) at 60°C (3 mm thick) dried for 24 h. The study found that the drying method significantly (p < 0.05) affected the texture, color, and general taste of peaches. The results showed that processing treatments combined with different drying conditions affected the physical properties of the peach. RWD in slices reduced water content to 0.05 kg H2O/kg in 40 min, showing fewer effects on color attributes. A surface response analysis on RWD showed good correlations for water activity (R2 = 0.8652-0.9894) and moisture content (R2 = 0.7048-0.9826). A higher diffusion coefficient (1.63 × 10-6 m2 s-1) was observed for RWD in slices with 3 × 10-3 m of thickness; however, for RWD-MD, differences in diffusion coefficients were present for the lowest MD addition (0.12 kg/kg), vitamin C was not detected on the dried slices, and higher concentration of ß-carotene (175.88 µg/100 g) was found on the thinner slices. Principal component analysis showed that RWD in the slices was the most suitable drying process, followed by OD. Sensory analysis showed good acceptability for RWD slices after 30 days of storage.

How the type of dairy production system affects the nutrient balance from an environmental and economic perspective.

The knowledge of nutrient flow in dairy farms has to be explored to find optimized strategies for efficient nutrient conversion to milk. This study aims to improve the understanding of variances in nitrogen and phosphorus balance and efficiency indicators between dairy farm systems. The study analyzed 67 dairy cattle farms located in the watershed Lajeado Tacongava, Rio Grande do Sul State, Brazil. Selected dairy farms represented three production systems: confined (3 farms); semi-confined (7 farms); pasture-based (57 farms). Input-output nutrient balances were calculated at the dairy system level for nitrogen and phosphorus over a year. Inputs are feed and fertilizer and outputs are milk and meat. The main nitrogen and phosphorus input on the all farms resulted from the feed. The average N and P surplus on pasture-based farms were 352 and 49 kg ha-1 year-1, respectively. In semi-confined systems were 508 and 63 kg ha-1 year-1 and in confined systems were 786 and 70 kg ha-1 year-1. When considering the monetary value of the total N surplus, the averages were US$ 2.615, 4.950, and 12.171 for pasture-based, semi-confined and confined systems respectively. Monetary values of P surplus were US$ 346, 588, and 1119 for pasture-based, semi-confined and confined. The productive aspects that most determined the values of N and P surplus were the total number of lactating cows and the farm area. Results indicate that surplus can partially replace chemical nitrogen fertilizer, except in the confined system, and fully replace phosphorus fertilizer. Confined farms presented values to use surplus as fertilizer greater than the crop demand. For the other production systems, it happens only for phosphorus. Large variability between dairy farms of the same production system and between different production systems was observed. It reflects the inherent productive, economic, and environmental conditions of each farm and system.

Modeling the economic impact for Chile of an import ban on genetically modified maize.

We estimate producer and consumer surplus changes due to a possible GM maize import ban in Chile, which produces only non-GM grains for internal use. Without foreign non-GM sources, the ban's effect on domestic maize prices would be so significant as to induce Chile to switch from net exporter to net importer of animal products. Fixed factor owners in farm production would benefit significantly, although non-GM maize imports would moderate gains. Total social welfare measures would decline considerably, requiring large offsetting noneconomic benefits for a ban's political viability. Without non-GM imports, internal maize prices would likely eliminate domestic animal product industries; with possible imports, industries and final consumers would suffer, but much less. Currently, the country is a net importer of grain and a net exporter of pork and poultry, and so most welfare losses on the demand side of the market for maize would be in terms of the economic rents generated by the pork and poultry sectors. International competition would protect final consumers to the extent that animal product imports based on GM feed were permitted.

Managing Reproduction in Hyperprolific Sow Herds.

The rearing of large litters from hyperprolific sows is a characteristic of modern genotypes. However, these sows have body and reproductive characteristics that differentiate them from the genotypes of the past decades, making it necessary to adopt different management strategies. This review describes the main care and challenges associated with the hyperprolificity of sows during the period in which replacement gilts are selected, along with gestation, parturition, lactation, and the weaning-estrus interval. It describes the challenges that these sows' piglets will face during the lactation period and includes some strategies adopted to develop these surplus piglets. In addition, it identifies areas where more research is needed to understand the reproductive management of modern genotypes.

A Circular Economy Approach to Integrate Divergent Ruminant Production Systems: Using Dairy Cow Feed Leftovers to Enhance the Out-of-Season Reproductive Performance in Goats.

Based on a circular economy approach, we evaluated the possible effect of targeted supplementation with leftover feed from dairy cows (i.e., intensive system) on the reproductive performance of crossbred/rangeland goats (i.e., extensive system) in arid Northern Mexico. During the deep-anestrous season (i.e., March-April, 25° North), multiparous goats (n = 38) with a similar body weight (BW) and body condition score (BCS) were randomly assigned to two groups: (1) supplemented group (SG; n = 19; BCS: 1.76 ± 0.07; BW: 43.7 ± 1.8 kg), receiving 400 g goat d-1 of dairy-cow-feed leftovers prior to grazing; and (2) non-supplemented group (NS; n = 19; BCS: 1.76 ± 0.06; BW: 44.3 ± 2.5 kg). Both groups were directed to the rangeland for a period of ≈8 h. While the experimental period lasted 36 d, the experimental breeding considered 11 d (d0-d10). The anovulatory status of goats was ultrasonographically confirmed on days -20, -10, and -1 prior to male-female interaction. Previously, bucks were separated for 3 weeks from the experimental females and received exogenous testosterone every third day (i.e., 50 mg i.m.) prior to mating. With respect to the response variables, namely BW, BCS, blood glucose levels (BGLs), estrus induction (GIE, %), latency to estrus (LTE, h), estrus duration (ED, h), and luteal tissue volume (LTV, mm), no differences (p > 0.05) occurred between experimental groups. However, the response variables, namely goats ovulating (GO, %; 78.9 vs. 47.3), total number of corpuses luteum (TNCL, n; 27 vs. 13), ovulation rate (OR, n; 1.42 vs. 0.73), multiple ovulation (MO, %; 73.3 vs. 55.5), and pregnancy rate on d 36 (PRd36, %, 68.4 vs. 36.8), favored (p < 0.05) the SG over the NS goats. Our results demonstrate that connecting the circularity of two divergent ruminant production systems (i.e., cow-intensive and goat-extensive) by using dairy cows' feed leftovers as a targeted supplementation strategy in anestrous goats under a marginal-rangeland production system enhanced out-of-season reproductive outcomes (i.e., ovulation rate and pregnancy rate), thus benefiting marginal goat producers and their families.

Beforeigners. Un caso de segregación en una metrópoli multiculturalista / A Case of Segregation in a Multiculturalist Metropolis in The Beforeigners Series

Tomando como eje la noción de plus de gozar propuesta por Jacques Lacan en su seminario De un Otro al otro, el presente trabajo aborda diferentes modos en que la serie de ciencia ficción noruega Beforeigners pone en escena modalidades de la segregación en una sociedad en la que predominan ideales como la tolerancia y la inclusión

Taking as its axis the notion of surplus jouissance [plus-de-jouir], proposed by Jacques Lacan in his seminar from an Other to the other, this paper addresses different ways in which the Norwegian science fiction series Beforeigners stages modalities of segregation in a society in which values such as tolerance and inclusion predominate

Tailored Informational Interventions for Reducing Surplus and Waste of Fruits and Vegetables in a Food Market: A Pilot Study.

This pilot study explored the effectiveness of tailored informational interventions to reduce the surplus and waste of fruits and vegetables at the distribution level in Chile. Stalls from a fresh food market were randomized to intervention (n = 5 selling fruits, n = 5 selling vegetables) or control (n = 4 selling fruits, n = 4 selling vegetables) groups. The causes of surplus and waste were estimated by questionnaires. Surplus, avoidable waste, and unavoidable waste were measured using direct quantification before and after the intervention, and were expressed relative to the initial stock. Before the intervention, the surplus was (median [25th-75th percentile]) 46.2% [33.3-51.2] for fruits and 51.5% [41.3-55.0] for vegetables; avoidable waste was 0.1% [0.0-0.8] for fruits and 1.8% [0.7-5.3] for vegetables; and unavoidable waste was 0.0% [0.0-1.0] for fruits and 0.0% [0.0-1.3] for vegetables. Planning and storage represented the main causes explaining surplus and waste. After the intervention, the intervention group decreased the surplus of fruits compared to the control group (-17.8% [-29.0--11.0] vs. 5.8% [-0.6-7.8], respectively; p = 0.016), without other differences. In conclusion, tailored informational interventions based on the causes of surplus and waste may reduce the surplus of fruits in a fresh food market. Interventions might also include management strategies for the surplus to improve grocers' business operations.

How risk perception regarding the COVID-19 pandemic affected household food waste: Evidence from Brazil.

Food waste is a worldwide problem. One third of the food produced in the world is lost or wasted every year. Most of this waste takes place downstream of the supply chain due to consumer behavior. This issue is expected to increase in both developed and emerging economies. With the beginning of the COVID-19 pandemic, a range of challenges led to changes in consumer behavior. This study explores household food waste behavior during the COVID-19 pandemic through the lens of the Theory of Planned Behavior. The risk perception regarding the pandemic was integrated into a broader framework, which was analyzed by Structural Equation Modeling. The sample comprises the participation of 452 Brazilian individuals. The results show that all the predictors incorporated in the model were statistically significant. The intention of reducing household food waste during the pandemic was found to be the strongest predictor of food waste behavior. Additionally, the pandemic apparently influenced consumers' perceptions about the control they think they have over food waste. This research has theoretical and managerial implications. From a theoretical perspective, this study identifies key predictors of household food waste by considering a period of health crisis in an emerging country. From a managerial standpoint, this research may provide a learning experience for future similar scenarios. Results may also motivate consumers to look for ways to reduce, reuse and recycle food waste.

Análisis bioético (subjetivismo moral) desde la percepción de los clínicos sobre la situación de los embriones sometidos a fecundación in vitro. Quito-Ecuador / Bioethical analysis (moral subjectivism) from the perception of clinicians on the situation of embryos subjected to in vitro fertilization. Quito-Ecuador / Análise bioética (subjetivismo moral) a partir da percepção dos médicos sobre a situação dos embriões submetidos à fertilização in vitro. Quito-Equador

Resumen: Objetivo. Analizar las percepciones y prácticas de los clínicos en relación con el manejo del embrión sometido a técnicas de fecundación in vitro. Metodología. Cualitativa (subjetivista y fenomenológico). Se realizaron 15 las entrevistas semiestructuradas aplicando un muestreo por saturación dirigidas a personal clínico que haya participado en procedimientos de fecundación in vitro. Los datos se analizaron con el programa Atlas Ti 8.0®. Resultado. Los clínicos consideran al embrión como un ser humano o futuro ser humano y, además, merecedor de respeto y consideración, proponiendo incluso mejoras en los procesos de manipulación y almacenaje. Conclusión. Los embriones no son considerados como entes susceptibles de recibir daño, desde argumentos no solo técnicos sino éticos. Desde la corriente principialista, se describe la necesidad de promover actitudes de responsabilidad y prudencia para evitar el dogmatismo (objetivismo moral) proponiendo una postura deliberativa.

Abstract: The objective of this paper is to analyze the perceptions and practices of clinicians in relation to the management of embryos subjected to in vitro fertilization techniques. Methodology is Qualitative (subjectivist and phenomenological). A total of 15 semi-structured interviews were conducted using saturation sampling for clinical personnel who have participated in vitro fertilization procedures. The data is analyzed with the Atlas Ti 8.0® program. Results: Clinicians consider the embryo as a Human being or future human being, in addition, deserving of respect and consideration even proposing improvements in the processes of handling and storage. Conclusion. Embryos are not considered as entities susceptible of damage from not only technical but ethical arguments. From the principialist current, the need to promote attitudes of responsibility and prudence to avoid dogmatism (moral objectivism) is described, proposing a deliberative position.

Resumo: Objetivo. Analisar as percepções e práticas dos médicos em relação ao manejo do embrião submetido a técnicas de fertilização in vitro. Metodologia. Qualitativo (subjetivo e fenomenológico). Foram realizadas 15 entrevistas semiestruturadas por amostragem de saturação para pessoal clínico que participou de procedimentos de fertilização in vitro. Os dados são analisados com o programa Atlas Ti 8.0®. Resultado. Os médicos consideram o embrião como um ser humano ou futuro, além de merecer respeito e consideração, propondo até melhorias nos processos de manuseio e armazenamento. Conclusão. Os embriões não são considerados como entidades suscetíveis a receber danos não apenas de argumentos técnicos, mas éticos. A partir da corrente principialista, descreve-se a necessidade de promover atitudes de responsabilidade e prudência para evitar o dogmatismo (objetivismo moral), propondo uma posição deliberativa.

Future assessment of the impact of the COVID-19 pandemic on the electricity market based on a stochastic socioeconomic model.

This paper proposes a time-series stochastic socioeconomic model for analyzing the impact of the pandemic on the regulated distribution electricity market. The proposed methodology combines the optimized tariff model (socioeconomic market model) and the random walk concept (risk assessment technique) to ensure robustness/accuracy. The model enables both a past and future analysis of the impact of the pandemic, which is essential to prepare regulatory agencies beforehand and allow enough time for the development of efficient public policies. By applying it to six Brazilian concession areas, results demonstrate that consumers have been/will be heavily affected in general, mainly due to the high electricity tariffs that took place with the pandemic, overcoming the natural trend of the market. In contrast, the model demonstrates that the pandemic did not/will not significantly harm power distribution companies in general, mainly due to the loan granted by the regulator agency, named COVID-account. Socioeconomic welfare losses averaging 500 (MR$/month) are estimated for the equivalent concession area, i.e., the sum of the six analyzed concession areas. Furthermore, this paper proposes a stochastic optimization problem to mitigate the impact of the pandemic on the electricity market over time, considering the interests of consumers, power distribution companies, and the government. Results demonstrate that it is successful as the tariffs provided by the algorithm compensate for the reduction in demand while increasing the socioeconomic welfare of the market.

Eco-Inefficiency Formula: A Method to Verify the Cost of the Economic, Environmental, and Social Impact of Waste in Food Services.

This study aimed to develop an Eco-Inefficiency (Ely) formula to verify the cost of the economic, environmental, and social impact of waste, applicable to food services (FS). Six stages were performed: identification of the terms that characterize food waste; definition of constructs influenced by food waste; identification of the variables that make up each construct; indicators capable of measuring the impact generated by food waste; definition of the mathematical formula; and EIy pilot test. The formula was based on eco-efficiency but focused on food waste. The constructs were translated into three dimensions of sustainability: environmental, social, and economic. Researchers created a score for the dimensions and the entire evaluation, based on a literature review. Water footprint, cleaning material, food production waste, the amount of rest-intake, and the amount of distribution leftover were evaluated on the environmental impact. The economic dimension variables were energy consumption to produce the wasted food, cost of raw material used in wasted food, and food handlers' wages for the economic impact measurement. The social impact variables were: energy density (ED), rest-intake (kcal/g), distribution of leftover ED (kcal/g), use of organic food, and food surpluses' donation. With an EIy application in each item, we have the item's score in each dimension. The higher value of an item, the higher is its influence on the dimension, allowing us to identify those with the most significant impact in the restaurant. The Environmental dimension presented the most significant problems in the assessed scenario. The eco-inefficiency formula identifies food waste's main critical points, allowing us to trace strategies to reduce food waste.

Sobre o colapso da objetalidade no discurso do capitalista / On the collapse of objectality in Capitalist discourse

RESUMO: O artigo refaz o percurso de Freud desde a exclusão de das Ding até o surgimento da dimensão da objetalidade por meio da constituição da realidade estruturada como fantasia. Com Lacan, coloca-se em evidência o objeto a como causa do desejo no Seminário da Angústia, no qual se discute a caducidade dos objetos que estabelecem bordas pelas quais a libido irá se deslocar em busca do objeto perdido. Enfim, aborda-se o colapso da objetalidade na vigência do discurso do capitalista. Em particular, é sublinhado o engodo desse discurso que faz supor acessível o objeto perdido na forma dos gadgets que a cada vez renovam a promessa de mais gozar.

Abstract: The article retraces Freud's path from the exclusion of das Ding to the emergence of the dimension of objectality through the constitution of reality structured as fantasy. In Lacan´s Seminary of Anguish, it is highlighted the concept of object taken as cause of desire, resulting from his discussion of the downfall of the objects that establish the borders through which the libido will move in search of the lost object. At the end, the collapse of objectality caused by the capitalist discourse is examined. In particular, the deception of this discourse is underlined, as it makes it seem as if the lost object is accessible in the form of gadgets that each time renew the promise of more enjoyment.

Del derecho comercial a la Economía solidaria / From commercial law to solidarity economy

Resumen El derecho comercial a través de la historia no ha dado cuenta de la economía solidaria, lo que ha provocado una serie de equívocos conceptuales que impiden observar que existen otras formas de interacción mercantil que no están mediadas por el intercambio monetario exclusivamente y sin que se haga referencia al trueque como única forma cooperativa, ya que ello desconoce otras formas de relaciones de cambio, tales como la donación, o la producción responsable de productos solo dirigidos al cubrimiento de necesidades básicas y no a la acumulación mercantil. En estas nuevas modalidades que podemos encontrar como el Blockchain, redes, plataformas, Apps, y otras cadenas logarítmicas que pueden ayudar a construir intercambios no capitalistas, que a su vez permitan repensar la forma de producir y consumir de las sociedades modernas.

Abstract Commercial law throughout history has not accounted for solidarity economy, which has led to a series of conceptual misunderstandings. These prevent us from observing that there are other forms of commercial interaction, which are not mediated by monetary exchange exclusively, and without being referred to barter as the only cooperative form since they do not recognize other forms of exchange relationships, such as donation, or responsible production of products. The latter are only aimed at the coverage of basic needs, and not to the commercial accumulation. In these new modalities, we can find Blockchain, networks, platforms, Apps, and other logarithmic chains, which can help build noncapitalist exchanges, which in turn, allow to reconsider the way of production and consumption of modern societies.

Impacto económico de la adopción de tecnología para la producción de frijol en condiciones de temporal en el norte centro de México / Economic impact of technology adoption on bean production under rainfed conditions in northern central Mexico

Resumen La asignación de recursos públicos a la investigación agropecuaria es un factor de desarrollo para el sector agroalimentario del país, pero deben estar orientados eficientemente hacia la generación de productos tecnológicos que otorguen beneficios a la población. El objetivo de este trabajo fue evaluar el beneficio económico a nivel sistema de producción y sociedad, derivado de la inversión pública en investigación y desarrollo, del paquete tecnológico para la producción de frijol en zonas de temporal de la región norte centro de México. Para evaluar el impacto en los sistemas de producción, se aplicaron 42 encuestas a productores adoptantes del paquete tecnológico en municipios de Aguascalientes y San Luis Potosí; mientras que, para el impacto a nivel sociedad, se estimó el retorno económico que produjo la inversión pública utilizada en el proceso de generación y adopción de la tecnología en el periodo 2009a 2025. La medición se realizó a través del valor actual neto (VAN), la tasa interna de retorno (TIR) y la relación beneficio costo (R B/C). El costo de producción de los adoptantes fue mayor en 36.3 % comparado con la tecnología tradicional; en tanto que, el rendimiento aumentó en 102 % y el ingreso neto incrementó en 322.6 %. A nivel sociedad, la evaluación reveló un VAN de $ 10.9 millones, lo que representó 4.1 veces lo invertido en la generación de la tecnología. La R B/C fue de 5.1 y la TIR fue mayor a la tasa media real de rendimiento considerada (9.5 %). El desarrollo y transferencia del paquete tecnológico para la siembra de frijol representó una buena inversión de recursos públicos, beneficiando a la población y a los productores, porque incrementa la producción alimentaria y el ingreso neto del agricultor.

Abstract The allocation of public resources to agricultural research is a factor of development for the agri-food sector of the country and should be efficiently oriented towards the generation of technological products that provide benefits to the population. The aim of this work was to evaluate the economic benefit at a level of production system and society, derived from public investment in research and development of the technological package for dry bean crop production in rainfed areas in north central Mexico. To evaluate the impact on the production systems, 42 questionnaires were administered to users of the technological package in municipalities of Aguascalientes and San Luis Potosí. Likewise, in order to assess the impact at a society level, the economic return produced by the public investment used in the generation and adoption process of technology in the 2009 to 2025 period was estimated. The evaluation was performed through the net present value (NPV), the internal rate of return (IRR) and the cost benefit ratio (B/C R). The production cost for adopters was 36.3 % higher compared to traditional technology; however, the yield increased by 102 % and the net income increased by 3226 %. At a society level, the evaluation revealed an NPV of $ 10.9 million, which represented 4.1 times more than what was invested in the generation of technology; the B/C R was 5.1 and the IRR was higher than the real average rate of return considered (9.5 %). The development and transfer of the technological package for sowing beans represented a good investment of public resources, benefiting the population and producers, because it increases food production and farmers' net income.

From Treatment to Containment to Enterprise: An Ethno-history of Therapeutic Communities in Puerto Rico, 1961-1993.

Unpaid work is now a central therapy in Puerto Rican therapeutic communities, where substance users reside and seek to rehabilitate each other, often for years at a time. Once a leading treatment for addiction in mainland United States, therapeutic communities were scaled back in the 1970s after they lost federal endorsement. They continue to flourish in Puerto Rico for reasons that have less to do with their curative powers than with their malleability as multi-purpose social enterprises and their historical co-option by state, market and family actors who have deployed them for a variety of purposes. Their endurance from the 1960s to the neoliberal present obliges us to recognize their capacities as what Mizruchi calls abeyance mechanisms whereby 'surplus' populations, otherwise excluded from labor and home, are absorbed into substitute livelihoods. Having initially emerged as a low-cost treatment, in a context of mass unemployment and prison-overcrowding they now thrive as institutions of containment and informal enterprise.

Ex-ante impact assessment of GM maize adoption in El Salvador.

Bacillus thuringiensis (Bt) white maize was field tested in El Salvador in 2009. Results showed sufficient pest abatement, eliminating the need for insecticide applications, and an average yield increase of 18% above that of the most widely cultivated conventional hybrid. This article presents an ex ante economic impact assessment of Bt maize adoption in El Salvador. Ten-year economic surplus projections show a considerable welfare gain for the overall economy, with consumers being the principal beneficiaries. Trade implications of adopting Bt maize are analyzed and appropriate alternatives to possible market shutdowns are explored. Results obtained in this study could compliment the agronomic evaluation of Bt maize and become part of the Salvadoran government decision process on Bt maize adoption.

The homology between surplus-value and surplus-jouissance on the basis of the capitalist subjectiveness / A homologia entre mais-valia e mais-de-gozar nas bases da subjetividade capitalista

RESUMO: Esse trabalho é motivado pela homologia estabelecida, por Lacan, entre a mais-valia e o mais-de-gozar. Buscamos evidenciar o embasamento dessa homologia e apontar seus efeitos nos fundamentos da subjetividade capitalista. Para tanto, combinamos a leitura do Seminário 16, de Lacan, a uma abordagem de O capital, de Marx. Nesse processo, analisamos as articulações significantes do valor, do dinheiro e do fetiche na conformação da ordem simbólica do discurso capitalista.

Abstract: This paper is an examination of the homology between surplus-value and surplus-jouissance, as set out by Lacan. We seek to demonstrate the basis of this homology and point out its effects on capitalist subjectivity. To this end, we combine a reading of Lacan's Seminar XVI with Marx's Capital. Throughout this process, we analyze how the articulation of signifiers, such as value, money and fetish, configures the symbolic order of capitalist discourse.

Pregnancy and delivery rates after vitrification of in vitro -produced Nelore ( Bos indicus ) embryos under field conditions / Tasas de preñez y nacimientos después de la vitrificación de embriones Nelore (Bos indicus) producidos in vitro bajo condiciones de campo / Taxas de prenhez e nascimentos após vitrificação de embriões Nelore (Bos indicus) produzidos in vitro sob condições de campo

Abstract Background: Cryopreservation preserves cellular viability under low temperatures, resulting in diminished intracellular enzymatic activity and reduced cellular metabolism that ultimately allows preserving genetic material for indefinite periods of time. Embryos submitted to cryopreservation suffer from considerable morphological and functional damage, resulting in reduced survival and development rates. Objective: To evaluate pregnancy and delivery rates of in vitro-produced (IVP) Nellore (Bos indicus) embryos after vitrification under field conditions. Methods: The IVP embryos at blastocyst (Bl) and expanded blastocyst (Bx) were transferred fresh (n= 137) or after vitrification (n= 127). Results: Pregnancy rates at 35 d for fresh embryos were lower in Bl (41.6) than in Bx (60.9) (p<0.05). After vitrification, pregnancy rates were similar at 35 d between Bl (38.0) and Bx (47.6) (p>0.05). Pregnancy loss at 60 d were similar (p>0.05) for both fresh (Bl: 3.1 and Bx: 4.8) and vitrified embryos (Bl: 1.9 and Bx: 4.7). Delivery rates were similar between groups (p>0.05). Conclusion: Both pregnancy and delivery rates of Bos indicus IVP embryos vitrified under field conditions are indistinguishable from fresh embryos.

Resumen Antecedentes: La criopreservación se caracteriza por el mantenimiento de la viabilidad celular a bajas temperaturas, resultando en reducido metabolismo y actividad enzimática intracelular, lo que permite la preservación del material genético por períodos de tiempo indefinidos. Los embriones sometidos a ésta técnica sufren daños morfológicos y funcionales considerables, dando como resultado una sobrevivencia y tasas de desarrollo reducidas. Objetivo: Evaluar la tasa de preñez a partir de embriones Nelore (Bos indicus) producidos in vitro (IVP) después de la vitrificación bajo condiciones de campo. Métodos: Embriones IVP en los estadios de blastocisto (Bl) y blastocisto expandido (Bx) se transfirieron en fresco (n= 137) o después de la vitrificación (n= 127). Resultados: La tasa de preñez a los 35 d fue menor para los embriones transferidos en fresco en fase Bl (41,6) en relación con los Bx (60,9) (p<0,05). Después de la vitrificación, las tasas de preñez a los 35 d fueron similares entre Bl (38,0) y Bx (47,6) (p>0,05). Las pérdidas de preñez a los 60 d fueron similares (p>0,05) tanto para embriones en fresco en Bl (3,1) y Bx (4,8) como para los vitrificados (Bl: 1,9 y Bx: 4,7). Las tasas de nacimiento fueron similares entre los grupos (p>0,05). Conclusión: Las tasas de preñez y nacimiento de embriones IVP vitrificados de Nelore (Bos indicus) bajo condiciones de campo son semejantes a las de embriones en fresco.

Resumo Antecedentes: A criopreservação é caracterizada pela manutenção da viabilidade celular em baixas temperaturas, resultando em atividade enzimática intracelular e metabolismo celular reduzido, que permite a preservação do material genético por períodos indefinidos de tempo. Embriões submetidos à criopreservação sofrem danos morfológicos e funcionais consideráveis, resultando em sobrevivência reduzida e menores taxas de desenvolvimento. Objetivo: Avaliar a taxa de prenhez a partir de embriões Nelore (Bos indicus) produzidos in vitro (IVP) após a vitrificação sob condições de campo. Métodos: Embriões IVP nos estádios de blastocisto (Bl) e blastocisto expandido (Bx) foram transferidos a fresco (n= 137) ou depois da vitrificação (n= 127). Resultados: A taxa de prenhez aos 35 d foi menor para os embriões transferidos a fresco na fase de Bl (41,6), em relação aos Bx (60,9) (p<0,05). Apos a vitrificação, as taxas de prenhez foram semelhantes aos 35 d entre Bl (38,0) e Bx (47,6) (p>0,05). As perdas de prenhez aos 60 d foram semelhantes (p>0,05) tanto para embriões a fresco nos estádios de Bl (3,1) e Bx (4,8), e vitrificados em Bl (1,9) e Bx (4,7). As taxas de nascimentos foram semelhantes entre os grupos (p>0,05). Conclusão: As taxas de prenhez e nascimentos dos embriões IVP vitrificados de Nelore (Bos indicus) sob condições de campo é semelhante àquela dos embriões a fresco.

Nitrogen utilisation efficiency in small-scale dairy systems in the highlands of Central Mexico.

Nitrogen (N) plays an important role in small-scale dairy systems, both in production costs and as an indicator of environmental impact. The objective of this study was to quantify nitrogen inputs and outputs to identify areas for improvement in nitrogen utilisation efficiency (NUE). Evaluation was in 12 small-scale dairy farms with different feeding strategies. Six followed the traditional cut and carry of irrigated temperate pastures (CUT), and six have implemented grazing of pastures (GRZ), quantifying N inputs and outputs from May 2016 to April 2017. Data were analysed by ANOVA following a split-plot model with season (rainy or dry) as main plots and feeding strategy (CUT or GRZ) as split-plots, with results in kilograms N per hectare and kilograms N per cow. There were differences (P < 0.05) between seasons and strategies in N inputs from purchased N fertilisers and purchased feeds as concentrates and roughages, showing different N inputs and outputs whether in CUT or GRZ strategies. There were also significant interactions between seasons and strategies as in the sale of animals, where GRZ sell throughout the year, while CUT sell at the beginning of the dry season. N balance ranged from 33.9 to 183.0 kg N/ha, and 37.8 to 111.0 as kilograms N per cow with an interaction (P < 0.05) between season and strategies. There was a larger N surplus in GRZ during the rainy season from fertiliser inputs, which reduced N utilisation efficiency (NUE). Mean NUE in kilograms N per hectare and kilograms N per cow was 19%, with the higher efficiency for GRZ in the dry season. Farms with the best NUE had lower use of fertilisers and purchased feeds.

Marx e a pobreza ou a influência do aumento do capital para a classe trabalhadora / Marx and poverty or the influence of the increase of capital to the working class

O artigo, inicialmente, problematiza a ampla utilização nos estudos sobre pobreza desde uma perspectiva marxista da "Lei Geral da Acumulação Capitalista", apresentada por Marx no capítulo XXIII do Livro Primeiro de O Capital. Tais estudos parecem considerar que, nesse capítulo, o objetivo específico de Marx é discutir a questão da pobreza. Em seguida, o artigo sustenta que a rigor a Lei não consiste, como costuma ser lida, em uma "teoria da pauperização" desenvolvida por Marx. Com isso, revela, na sequência, que o seu objetivo é examinar a influência que o aumento do capital tem sobre a sorte da classe trabalhadora a partir da apresentação da lei tendencial característica da dinâmica do capitalismo. Destaca-se que na exposição realizada por Marx são colocadas em questão as condições vitais e de trabalho de forma ampla, não limitando a análise à preocupação com possíveis aumentos salariais ou melhoria da qualidade de vida como resultado de um maior acesso ao consumo no interior dessa forma de organização social.

The article initially discusses the wide use of the "General Law of Capitalist Accumulation" in studies on poverty from a Marxist perspective, presented by Marx in Chapter XXIII of Capital, vol. I. Such studies seem to consider that in this chapter the specific goal of Marx is to discuss the issue of poverty. Then, the article argues that the Law actually does not consist in a "theory of impoverishment" developed by Marx. In opposition to this rather usual interpretation, it sustains that, after the presentation of the tendency of the law characteristic of the dynamics of capitalism, Marx's goal in that chapter is to examine the influence that the increase of capital has on the fate of the working class. It should be emphasized that in the explanation put forward by Marx questions relative to life and working conditions are examines in broad terms, so that the analysis is not limited to the concern with possible wage increases or improvements in the quality of life as a result of greater access to consumption within this form of social organization.