Productivity Differences between Male and Female Managed Farms in the Eastern and Central Highlands of Kenya

This study was carried out in an agroforestry farming system in the central highlands of Kenya. The purpose of the study was to compare the productivity and technical efficiency of male and female managed farms. The study also sought to investigate the sources of differences in the Total Value Product and the technical efficiency of farms. Using a female dummy, the study found no evidence of differences in total value product between male and female managed farms. Male managed farms were however more technically efficient than female managed farms. The highest proportion of farms in the lowest bracket of efficiency levels was female managed farms. The total value product was found to be positively affected by age of the farmer, female labour and inputs while it was negatively affected by land size.Farm Management, Labor and Human Capital,

Formation of rings in galactic discs by infalling small companions

We use N-body simulations to study the formation of rings in a disc galaxy by the impact of a small spherical companion. Both barred and nonbarred target discs are considered. We discuss the effect of the properties of the target disc (distribution of mass in the disc, velocity dispersion, etc.) as well as of the mass and orbit of the companion on the properties of the rings, such as their amplitude, width, shape, expansion velocity and lifetime. In particular the amplitude, width, lifetime and expansion velocity of the first ring increase considerably with companion mass, and so does the expansion velocity of the particles in it and the total extent of the disc after the interaction. We also discuss the formation and evolution of spokes and show that they can be caused by companions of relatively small mass. In our three examples of oblique impacts on barred target galaxies we note important transient displacements of the bar, as well as changes of its pattern speed and size. An asymmetric pseudoring is formed in each case, and during the first stages of its evolution the bar forms part of it.Comment: 21 pages Latex, 22 figures, of which 7 as separate gif-files. Requires mn.sty, accepted for publication in MNRAS. High resolution version at http://www-obs.cnrs-mrs.fr/dynamique/pap/ring.htm

Is attending a mental process?

The nature of attention has been the topic of a lively research programme in psychology for over a century. But there is widespread agreement that none of the theories on offer manage to fully capture the nature of attention. Recently, philosophers have become interested in the debate again after a prolonged period of neglect. This paper contributes to the project of explaining the nature of attention. It starts off by critically examining Christopher Mole’s prominent “adverbial” account of attention, which traces the failure of extant psychological theories to their assumption that attending is a kind of process. It then defends an alternative, process-based view of the metaphysics of attention, on which attention is understood as an activity and not, as psychologists seem to implicitly assume, an accomplishment. The entrenched distinction between accomplishments and activities is shown to shed new light on the metaphysics of attention. It also provides a novel diagnosis of the empirical state of play

The farmer trainers approach in technology dissemination in Uganda: Farmer trainers’ and trainees’ perspectives.

This working paper presents the results of the first phase of a study that aims to determine the effectiveness of the farmer trainers approach in the dissemination of feed technologies in the East Africa Dairy Development Project (EADD). The starting point of this study is in the recognition that public sector extension services are no longer able to provide small scale farmers with adequate extension services. As a result, new approaches and mechanisms are being developed to fill the gap. One such approach that is being used by the EADD project is the volunteer farmer trainers approach. It is a form of farmer-to farmer extension where farmers host demonstration plots and take centre stage in information sharing. Although this approach has been in use in the EADD project since its inception in 2008, not much is understood about its effectiveness. A study was therefore initiated to assess its effectiveness. The study was organised into three phases. The first phase, which is the subject of this report, is an exploratory informal survey to collect qualitative data from both the trainers and trainees to be used in formulating hypothesis for more in depth formal surveys in the next phases. Group discussions were held in three sites of the EADD project in three districts, namely Jinja, Mukono and Mityana to get the perceptions of farmer trainers and trainees on the effectiveness of the approach. Farmer trainers have served an average of 15.6 months and train an average of 5 trainees per month. Most of them undertake their activities by foot and a few use their own bicycles. Farmer trainers use various means of mobilizing farmers for their training sessions. Training sessions are normally held at trading centres, local county halls, demonstration sites and homesteads of trainees and trainers. Farmer trainers are motivated by the desire to gain more knowledge/skills, improve their own livelihoods and those of other farmers in the community and becoming popular among other factors. Some of the costs that farmer trainers incur are: transport, time and bicycle maintenance. Benefits received range from gaining knowledge and skills, popularity, increasing social networks to satisfaction. Challenges faced include transport, lack of training materials and family conflicts involving some farmer trainees and their spouses. Some of the low-cost opportunities for improving the approach include provision of training materials (manila paper, marker pen, sample seeds) and certification of farmer trainers. If resources are available, bicycles would help improve performance. Farmer trainers are an important source of information to farmers. Rating of topics taught by trainers was mixed with some topics being rated highly in terms of relevance, understanding and ease of use while others were rated low. On technology uptake by farmer trainees, the highest uptake was for Napier (Elephant) grass and pasture improvement (50%), followed by calliandra (47%). Other technologies such as silage, hay, lablab, leuceana and setaria had less than 30% uptake

Development of a high temperature battery

High energy density battery for use on planet Venu

Development of a high temperature battery final report

Development of battery with lithium-magnesium alloy anode, molten cuprous chloride cathode, and zeolite separator cells and cupric oxide cathode and porous glass separator cell

Variation in carbon footprint of milk due to management differences between Swedish dairy farms

To identify mitigation options to reduce greenhouse gas (GHG) emissions from milk production (i.e. the carbon footprint (CF) of milk), this study examined the variation in GHG emissions among dairy farms using data from previous CF studies on Swedish milk. Variation between farms in these production data, which were found to have a strong influence on milk CF were obtained from existing databases of e.g. 1051 dairy farms in Sweden in 2005. Monte Carlo analysis was used to analyse the impact of variations in seven important parameters on milk CF concerning milk yield (energy corrected milk (ECM) produced and delivered), feed dry matter intake (DMI), enteric methane emissions, N content in feed DMI, N-fertiliser rate and diesel used on farm. The largest between farm variation among the analysed production data were N-fertiliser rate (kg/ha) and diesel used (l/ha) on farm (coefficient of variation (CV) 31-38%). For the parameters concerning milk yield and feed DMI the CV was approx. 11 and 8%, respectively. The smallest variation in production data was found for N content in feed DMI. According to the Monte Carlo analysis, these variations in production data led to a variation in milk CF of between 0.94 and 1.33 kg CO2 equivalents (CO2e) per kg ECM, with an average value of 1.13 kg/CO2e kg ECM. We consider that this variation of ±17% that was found based on the used farm data would be even greater if all Swedish dairy farms were included, as the sample of farms in this study was not totally unbiased. The variation identified in milk CF indicates that a potential exists to reduce GHG emissions from milk production on both national and farm level through changes in management. As milk yield and feed DMI are two of the most influential parameters for milk CF, feed conversion efficiency (i.e. units ECM produced per unit DMI) can be used as a rough key performance indicator for predicting CF reductions. However, it must be borne in mind that feeds have different CF due to where and how they are produced

Base sequence dependent sliding of proteins on DNA

The possibility that the sliding motion of proteins on DNA is influenced by the base sequence through a base pair reading interaction, is considered. Referring to the case of the T7 RNA-polymerase, we show that the protein should follow a noise-influenced sequence-dependent motion which deviate from the standard random walk usually assumed. The general validity and the implications of the results are discussed.Comment: 12 pages, 3 figure

Interspecies DNA acquisition by a naturally competent Acinetobacter baumannii strain

The human pathogen Acinetobacter baumannii possesses high genetic plasticity and frequently acquires antimicrobial resistance genes. Here we investigated the role of natural transformation in these processes. Genomic DNA from different sources, including from carbapenem-resistant Klebsiella pneumoniae strains, was mixed with A. baumannii A118 cells. Selected transformants were analysed by whole-genome sequencing. In addition, bioinformatics analyses and in silico gene flow prediction were also performed to support the experimental results. Transformant strains included some that became resistant to carbapenems or changed their antimicrobial susceptibility profile. Foreign DNA acquisition was confirmed by whole-genome analysis. The acquired DNA most frequently identified corresponded to mobile genetic elements, antimicrobial resistance genes and operons involved in metabolism. Bioinformatics analyses and in silico gene flow prediction showed continued exchange of genetic material between A. baumannii and K. pneumoniae when they share the same habitat. Natural transformation plays an important role in the plasticity of A. baumannii and concomitantly in the emergence of multidrug-resistant strains.Fil: Traglia, German Matias. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Place, Kori. California State University; Estados UnidosFil: Dotto, Cristian Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Fernandez, Jennifer. California State University; Estados UnidosFil: Montaña, Sabrina Daiana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones en Microbiología y Parasitología Médica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones en Microbiología y Parasitología Médica; ArgentinaFil: Bahiense, Camila dos Santos. California State University; Estados UnidosFil: Soler Bistue, Alfonso J. C.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Iriarte, Andres. Universidad de la Republica. Facultad de Medicina; UruguayFil: Perez, Federico. Louis Stokes Cleveland Department Of Veterans Affairs; Estados UnidosFil: Tolmasky, Marcelo E.. California State University; Estados UnidosFil: Bonomo, Robert A.. Louis Stokes Cleveland Department Of Veterans Affairs; Estados UnidosFil: Melano, Roberto Gustavo. Public Health Ontario Laboratories; CanadáFil: Ramirez, Maria Soledad. California State University; Estados Unido