989 resultados para Agricultural populations


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The role urban and peri-urban agriculture (UPA) plays in reducing urban poverty and ensuring environmental sustainability was recognized by the Millennium Development Goals (MGDs). India is the world’s largest democratic nation with a population of 1.2 billion. The rapid urbanization and high proportion of people below the poverty line along with higher migration to urban areas make India vulnerable to food crisis and urbanization of poverty. Ensuring jobs and food security among urban poor is a major challenge in India. The role of UPA can be well explained and understood in this context. This paper focuses on the current situation of UPA production in India with special attention to wastewater irrigation. This question is being posed about the various human health risks from wastewater irrigation which are faced by farmers and labourers, and, secondly by consumers. The possible health hazards involve microbial pathogens as well as helminth (intestinal parasites). Based on primary and secondary data, this paper attempts to confirm that UPA is one of the best options to address increasing urban food demand and can serve to complement rural supply chains and reduce ecological food prints in India. “Good practice urban and peri-urban agriculture” necessitates an integrated approach with suitable risk reduction mechanisms to improve the efficiency and safety of UPA production.

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Background: The most common application of imputation is to infer genotypes of a high-density panel of markers on animals that are genotyped for a low-density panel. However, the increase in accuracy of genomic predictions resulting from an increase in the number of markers tends to reach a plateau beyond a certain density. Another application of imputation is to increase the size of the training set with un-genotyped animals. This strategy can be particularly successful when a set of closely related individuals are genotyped. ----- Methods: Imputation on completely un-genotyped dams was performed using known genotypes from the sire of each dam, one offspring and the offspring’s sire. Two methods were applied based on either allele or haplotype frequencies to infer genotypes at ambiguous loci. Results of these methods and of two available software packages were compared. Quality of imputation under different population structures was assessed. The impact of using imputed dams to enlarge training sets on the accuracy of genomic predictions was evaluated for different populations, heritabilities and sizes of training sets. ----- Results: Imputation accuracy ranged from 0.52 to 0.93 depending on the population structure and the method used. The method that used allele frequencies performed better than the method based on haplotype frequencies. Accuracy of imputation was higher for populations with higher levels of linkage disequilibrium and with larger proportions of markers with more extreme allele frequencies. Inclusion of imputed dams in the training set increased the accuracy of genomic predictions. Gains in accuracy ranged from close to zero to 37.14%, depending on the simulated scenario. Generally, the larger the accuracy already obtained with the genotyped training set, the lower the increase in accuracy achieved by adding imputed dams. ----- Conclusions: Whenever a reference population resembling the family configuration considered here is available, imputation can be used to achieve an extra increase in accuracy of genomic predictions by enlarging the training set with completely un-genotyped dams. This strategy was shown to be particularly useful for populations with lower levels of linkage disequilibrium, for genomic selection on traits with low heritability, and for species or breeds for which the size of the reference population is limited.

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Comparing the experiences of selected Latin America and the Caribbean countries and their trajectories over the past 15 years offers rich insights into the dynamics and causes for not meeting the 2015 MDGs. They also offer clues for post-MDG strategies. Central to achieving sustainable growth are government policies able to support small and medium-sized farms and peasants, as they are crucial for the achievement of several goals, centrally: to achieve food security; to provide a sound and stable rural environment able to resist external (financial) shocks; to secure healthy food; to secure local food; and to protect vibrant and culturally rich local communities. This paper analyses and compares the most successful government policies to the least successful policies carried out over the last 15 years in selected Latin American and Caribbean countries and based on this analysis, offers strategies for more promising post-MDG politics, able to reduce poverty, reduce inequality, fight back informality, and achieve more decent work in poor countries.

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This paper is an attempt to map the global land acquisitions with a focus on Indian MNCs in acquiring overseas land for agricultural purposes. It tries to outline the contemporary political economy of capital accumulation at the global level, especially, in the emerging developing economies like India and China, where the emergence of a new capitalist class has engaged itself into acquisition of land and control of other natural resources in Africa, Latin America, Eastern Europe and South East Asia, for example, water and other minerals to secure itself from the eventual losses of ongoing economic crisis and to earn profit from the volatile agricultural commodity markets. This sway of control of resources by the MNCs has got paramount State support under the helm of neoliberal policies. The paper provides scale of overseas land acquisitions at the current juncture and tries to highlight its causes and the major implications associated with it.

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In composite agricultural materials such as grass, tee, medicinal plants; leaves and stems have a different drying time. By this behavior, after leaving the dryer, the stems may have greater moisture content than desired, while the leaves one minor, which can cause either the appearance of fungi or the collapse of the over-dried material. Taking into account that a lot of grass is dehydrated in forced air dryers, especially rotary drum dryers, this research was developed in order to establish conditions enabling to make a separation of the components during the drying process in order to provide a homogeneous product at the end. For this, a rotary dryer consisting of three concentric cylinders and a circular sieve aligned with the more internal cylinder was proposed; so that, once material enters into the dryer in the area of the inner cylinder, stems pass through sieve to the middle and then continue towards the external cylinder, while the leaves continue by the inner cylinder. For this project, a mixture of Ryegrass and White Clover was used. The characteristics of the components of a mixture were: Drying Rate in thin layer and in rotation, Bulk density, Projected Area, Terminal velocity, weight/Area Ratio, Flux through Rotary sieve. Three drying temperatures; 40°C, 60° C and 80° C, and three rotation speeds; 10 rpm, 20 rpm and 40 rpm were evaluated. It was found that the differences in drying time are the less at 80 °C when the dryer rotates at 40 rpm. Above this speed, the material adheres to the walls of the dryer or sieve and does not flow. According to the measurements of terminal velocity of stems and leaves of the components of the mixture, the speed of the air should be less than 1.5 m s-1 in the inner drum for the leaves and less than 4.5 m s-1 in middle and outer drums for stems, in such way that only the rotational movement of the dryer moves the material and achieves a greater residence time. In other hand, the best rotary sieve separation efficiencies were achieved when the material is dry, but the results are good in all the moisture contents. The best rotary speed of sieve is within the critical rotational speed, i.e. 20 rpm. However, the rotational speed of the dryer, including the sieve in line with the inner cylinder should be 10 rpm or less in order to achieve the greatest residence times of the material inside the dryer and the best agitation through the use of lifting flights. With a finite element analysis of a dryer prototype, using an air flow allowing speeds of air already stated, I was found that the best performance occurs when, through a cover, air enters the dryer front of the Middle cylinder and when the inner cylinder is formed in its entirety through a sieve. This way, air flows in almost equal amounts by both the middle and external cylinders, while part of the air in the Middle cylinder passes through the sieve towards the inner cylinder. With this, leaves do not adhere to the sieve and flow along drier, thanks to the rotating movement of the drums and the showering caused by the lifting flights. In these conditions, the differences in drying time are reduced to 60 minutes, but the residence time is higher for the stems than for leaves, therefore the components of the mixture of grass run out of the dryer with the same desired moisture content.

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The main objective of this thesis was to determine the potential impact of heat stress (HS) on physiological traits of lactating cows and semen quality of bulls kept in a temperate climate. The thesis is comprised of three studies. An innovative statistical modeling aspect common to all three studies was the application of random regression methodology (RRM) to study the phenotypic and genetic trajectory of traits in dependency of a continuous temperature humidity index (THI). In the first study, semen quality and quantity traits of 562 Holstein sires kept on an AI station in northwestern Germany were analyzed in the course of THI calculated from data obtained from the nearest weather station. Heat stress was identified based on a decline in semen quality and quantity parameters. The identified general HS threshold (THI = 60) and the thermoneutal zone (THI in the range from 50 to 60) for semen production were lower than detected in studies conducted in tropical and subtropical climates. Even though adult bulls were characterized by higher semen productivity compared to younger bulls, they responded with a stronger semen production loss during harsh environments. Heritabilities (low to moderate range) and additive genetic variances of semen characteristics varied with different levels of THI. Also, based on genetic correlations genotype, by environment interactions were detected. Taken together, these findings suggest the application of specific selection strategies for specific climate conditions. In the second study, the effect of the continuous environmental descriptor THI as measured inside the barns on rectal temperatures (RT), skin temperatures (ST), vaginal temperatures (VT), respiration rates (RR), and pulse rate (PR) of lactating Holstein Friesian (HF) and dual-purpose German black pied cattle (DSN) was analyzed. Increasing HS from THI 65 (threshold) to THI 86 (maximal THI) resulted in an increase of RT by 0.6 °C (DSN) and 1 °C (HF), ST by 3.5 °C (HF) and 8 °C (DSN), VT by 0.3 °C (DSN), and RR by 47 breaths / minute (DSN), and decreased PR by 7 beats / minute (DSN). The undesired effects of rising THI on physiological traits were most pronounced for cows with high levels of milk yield and milk constituents, cows in early days in milk and later parities, and during summer seasons in the year 2014. In the third study of this dissertation, the genetic components of the cow’s physiological responses to HS were investigated. Heat stress was deduced from indoor THI measurements, and physiological traits were recorded on native DSN cows and their genetically upgraded crosses with Holstein Friesian sires in two experimental herds from pasture-based production systems reflecting a harsh environment of the northern part of Germany. Although heritabilities were in a low range (from 0.018 to 0.072), alterations of heritabilities, repeatabilities, and genetic components in the course of THI justify the implementation of genetic evaluations including heat stress components. However, low repeatabilities indicate the necessity of using repeated records for measuring physiological traits in German cattle. Moderate EBV correlations between different trait combinations indicate the potential of selection for one trait to simultaneously improve the other physiological attributes. In conclusion, bulls of AI centers and lactating cows suffer from HS during more extreme weather conditions also in the temperate climate of Northern Germany. Monitoring physiological traits during warm and humid conditions could provide precious information for detection of appropriate times for implementation of cooling systems and changes in feeding and management strategies. Subsequently, the inclusion of these physiological traits with THI specific breeding values into overall breeding goals could contribute to improving cattle adaptability by selecting the optimal animal for extreme hot and humid conditions. Furthermore, the recording of meteorological data in close distance to the cow and visualizing the surface body temperature by infrared thermography techniques might be helpful for recognizing heat tolerance and adaptability in cattle.

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Lupus nephritis (LN) is one of the most serious complications of systemic lupus erythematosus (SLE) since it is the major predictor of poor prognosis. The purpose of this study was to examine the clinical and immunological characteristics associated with LN development during the course of SLE in Colombians. Therefore, patients with SLE followed at five different referral centers in Medellin, Bogota, and Cali were included in this cross-sectional and multicenter study. Factors influencing LN were assessed by conditional logistic regression analysis, adjusting by gender, age at onset, duration of disease, and city of origin. The entire sample population included 467 patients, of whom 51% presented with LN. The presence of anti-dsDNA antibodies (adjusted odds ratio (AOR), 2.06; 95% confidence interval (CI), 1.16–3.65), pleuritis (AOR, 3.82; 95% CI, 1.38–10.54), and hypertension (AOR, 2.63; 95% CI, 1.23–5.62) were positively associated with LN, whereas the presence of anti-La antibodies was a protective factor against LN development (AOR, 0.4; 95% CI, 0.19–0.85). A review of literature on LN in different populations is made. The identified clinical- and laboratory-associated factors would assist earlier diagnosis and guide decisions on therapeutic interventions on this critical and frequent complication of SLE.

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Este estudio explora el estado actual y el potencial competitivo de las exportaciones agrícolas colombianas a los mercados de Estados Unidos y la Unión Eurpea. Los mercados de estos paises industrializados se constituyen en los más importantes para Colombia, pero al mismo tiempo tienen varias restricciones en el sector agrícola. Este estudio mostrará que la competitividad no es solamente una función de los impedimentos locales o internacionales tales como la pobreza institucional, la baja capacidad tecnológica, la disponibilidad de capital, capital humano y mano de obra, sino también de impedimentos externos como el acceso a los mercados. Por lo tanto, éste es un importante objetivo del presente estudio con el objeto de proyectar posibles escenarios para el comercio colombiano, a fin de investigar la eliminación de estas restricciones. En la parte empírica se enfatizará en los impactos de las restricciones externas en el sentido de un estudio econométrico, sin embargo, la influencia de las restricciones internas será discutida como tal.

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In this chapter we provide a summary description of Colombian Competition Policy with an emphasis on the agricultural sector. Key developments and recent changes in institutional arrangements affecting competition policy, as it applies to the agricultural sector, are highlighted. Illustrative case studies are depicted to show the richness and complexity of policy developments and enforcement. Some general conclusions are drawn from this examination.

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We aim to contribute to the assessment of poverty impacts on the rural sector arising from agricultural policy adjustments in Colombia. For this we use an agriculture specialized static CGE model, jointly (sequentially) with a microsimulation model that allows for effective job relocation. Results indicate that the sectoral impact of the program implemented tends to be small and has considerable variability across crops. They also show that the highest impacts come from the irrigation and land improvements component of the program. Lastly, although it reduces poverty, poverty impacts are small and tend to concentrate in rural households toward the middle of the income distribution ladder.

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Entre muchas de las preocupaciones en el ámbito internacional está la desnutrición y la desigualdad social, por eso, esta investigación propone la logística humanitaria como herramienta para hacer más eficientes las Agrocadenas de suministro llegando de esta forma a las poblaciones más vulnerables. Gracias a esto, nace este proyecto a nivel internacional Con alianzas de Universidades en Colombia y Argentina. Para esta investigación es necesario responder preguntas como: ¿Qué es la Logística humanitaria? ¿Cuál es el alcance de la logística humanitaria? ¿Qué es una Agrocadenas? ¿Cómo se pueden optimizar las Agrocadenas a partir de la logística humanitaria? ¿Qué impacto tendría en Latinoamérica la mejora en los procesos de las Agrocadenas? Por Ultimo es importante resaltar, que en este proyecto se hará la caracterización de las Agrocadenas de tres productos importantes para la economía de los países anteriormente mencionados: maíz, arroz y trigo; se visualizaran sus puntos fuertes y débiles y así, lograr tener un mejor enfoque en cuanto los puntos más importantes a optimizar en toda la cadena.

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Ireland’s waters constitute one of the richest habitats for cetaceans in Europe. Marine mammals, particularly cetaceans, are known to be definitive hosts of digestive parasites from the Fm.Anisakidae. The main aim of this study is to collect and compile all the information available out there regarding parasites of the Fm. Anisakidae and their definitive hosts. Secondary objectives are to relate the presence of cetacean species with the presence of parasites of the Fm. Anisakidae and to determine whether this greater number of cetaceans relates to a greater level of parasitism. Prevalence and burdens of anisakids in definitive hosts vary widely with host species, geographic location, and season. Results from several post-mortem exams are given. However, they cannot be compared due to differences in collecting techniques. Anisakis simplex is the most commonly and widespread parasite found in the majority of the samples and in a major number of hosts, which include harbour porpoise, short-beaked common dolphin and bottlenose dolphin. Studies on harbour porpoise obtained prevalences of Anisakis spp. of 46% (n=26) and of 100% (n= 12). Another study in common dolphin reported a prevalence of 68% (n=25). Several reasons could influence the variations in the presence of Anisakis. Studies on commercially exploited fish have reported prevalences of Anisakis simplex ranging from 65-100% in wild Atlantic salmon and from 42-53.4% in Atlantic cod

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The origins of early farming and its spread to Europe have been the subject of major interest for some time. The main controversy today is over the nature of the Neolithic transition in Europe: the extent to which the spread was, for the most part, indigenous and animated by imitatio (cultural diffusion) or else was driven by an influx of dispersing populations (demic diffusion). We analyze the spatiotemporal dynamics of the transition using radiocarbon dates from 735 early Neolithic sites in Europe, the Near East, and Anatolia. We compute great-circle and shortest-path distances from each site to 35 possible agricultural centers of origin—ten are based on early sites in the Middle East and 25 are hypothetical locations set at 58 latitude/longitude intervals. We perform a linear fit of distance versus age (and vice versa) for each center. For certain centers, high correlation coefficients (R . 0.8) are obtained. This implies that a steady rate or speed is a good overall approximation for this historical development. The average rate of the Neolithic spread over Europe is 0.6–1.3 km/y (95% confidence interval). This is consistent with the prediction of demic diffusion(0.6–1.1 km/y). An interpolative map of correlation coefficients, obtained by using shortest-path distances, shows that the origins of agriculture were most likely to have occurred in the northern Levantine/Mesopotamian area