105,530 research outputs found
Letter, [Author unclear] to Paulina T. Merritt
No full textHandwritten letter to Paulina Merritt from an unknown author, October 1, 1876.
Praxis ecclesiasticae et saecularis cum actionum formulis et actis processuum hispano sermone compositis tomi tres /
No full textTexto a dos col.Error de pág.: de p. 163 pasa a 170"Grab. xil. en œ2"Ej. falto de las p. 41, 42, 115, 116, 117 y 118, las últimas p. mal encuadernadasCCPB000118109-2BHR/B-049-095.Perg.FDH 35002Hª Derecho/N-151 (1-2-3)œ6, A-S4, T-Y2, Z3, Aa-Tt4, A-L4, A-K4, a-m
Análise conjunta para experimentos em blocos casualizados completos aumentados
No full textO presente estudo visa a efetuar uma análise conjunta de ensaios em blocos casualizados completos aumentados, cada ensaio apresenta os mesmos t = c + z tratamentos, distribuídos em r blocos, onde os c tratamentos são considerados comuns, pois aparecem nos r blocos, e os z tratamentos são considerados regulares, pois aparecem uma única vez em um dos r blocos. Os blocos são formados por k parcelas, sendo k = c + pj, onde pj (j=1,2,...,r) é o número de tratamentos regulares por bloco. Para desenvolvê-lo, considerou-se o conjunto dos ensaios como um delineamento comum em blocos incompletos, baseado nos trabalhos de PIMENTEL GOMES e GUIMARÃES (1958), PAVATE (1961) e PIMENTEL GOMES (1970), admitindo-se que os ensaios apresentassem variâncias semelhantes.This paper has in view the joint analysis of augmented trials in randomised blocks. Each experiment had t = c + z, in r blocks, where we have c common treatments, that is, treatments present in each block, and z regular treatments, which appear in only one of the r blocks. Each block has k = c + pj plots, where pj (j=1,2,,r) is the number of regular treatments in it. The analysis was carried out, taking the whole set of trials as one experiment with incomplete blocks, having in view papers by PIMENTEL GOMES and GUIMARÃES (1958), PAVATE (1961) and PIMENTEL GOMES (1970), assuming that the trials had similar variances
Gauromydas Wilcox, Papavero & Pimentel
No full textGauromydas Wilcox, Papavero & Pimentel Gauromydas Wilcox, Papavero & Pimentel, 1989: 104. Type-species: Mydas heros Perty, 1833 (orig. des.). Diagnosis. Antenna at least as long as head width, or up to 2 times longer. Distal portion of postpedicel 5 to 6 times longer than wide (measures not taken for G. autuorii and G. m a t eu s sp. nov.). Hind femur 1.5 to 2.5 times wider than hind tibia. Hind tibia with well-developed ventral keel and apical spur, the latter always larger than width of hind tarsomere 1 (except in female G. mystaceus). Hind tarsomere 1 2–3.4 times longer than wide, about as long as T 3–4 together, slightly shorter than tarsomere 5 or up to 2.2 times longer. Phallus with a distinct dorsal crest (phallic crest). Distribution. Argentina, Brazil, Costa Rica, Guyana, French Guyana, Paraguay, Peru, Trinidad and Tobago, Surinam.Published as part of Calhau, Julia, Lamas, Carlos José Einicker & Nihei, Silvio Shigueo, 2015, Review of the Gauromydas giant flies (Insecta, Diptera, Mydidae), with descriptions of two new species from Central and South America, pp. 392-411 in Zootaxa 4048 (3) on page 398, DOI: 10.11646/zootaxa.4048.3.3, http://zenodo.org/record/24578
[P]ra[xis] ecclesiast[icae] et saecularis : cum actiorum formulis et actis procesuum ... : tomi tres
No full textSign.: [calderón], A-S, T-Y, Z, 2A-2T, A-L, A-K, a-mTexto a dúas colPort. con esc. xilErro tip. de páx.: da p. 163 pasa á 170Tomus secundus e tomus tertiu
Caracterização da produção de batata-doce em Mariana Pimentel (RS): um estudo exploratório.
No full textÉ fundamental levantar as demandas tecnológicas dos agentes econômicos para que a pesquisa agronômica tenha a máxima aderência à necessidade da cadeia produtiva. O presente estudo teve como principal objetivo caracterizar a produção de batata-doce em Mariana Pimentel, o município com maior produção dessa hortaliça no estado do Rio Grande do Sul.Editores:Adalton Mazetti Fernandes, Unesp; André Ricardo Zeist, UFSC
Structural, mechanical and tribological properties of Mo–S–C solid lubricant coating
No full textMo–S–C self-lubricating coatings were deposited by d.c. magnetron sputtering from carbon and molybdenum disulphide targets. The power ratio of the targets was varied in order to prepare films with carbon content in the range 0–55 at.%. Whatever the carbon content, the S/Mo ratio was higher than 1.25. The hardness of the films increased almost linearly with the carbon content. X-ray photoelectron spectroscopy showed evidence of Mo–C bonds; nevertheless, the size of molybdenum carbide grains was expected to be very small, since X-ray diffraction did not reveal any peaks related to any Mo–C phase. The coatings tested by pin-on-disc exhibited low friction, decreasing with increasing carbon content, when humid air was present. In nitrogen, the friction of all films was lower than 0.02 except for the reference MoS2 (0.04). Mo–S–C outperformed the wear resistance of MoS2; on the other hand, the results were in some cases hindered by the low adhesion of the coatings. The films were very sensitive to air exposure leading to surface oxidation.<br/
Is there a need for a more sustainable agriculture?
No full textIn this paper the environmental impact of current agriculture
practices is reviewed. Soil loss (along with soil fertility), increasing water demand from agricultural practices and environmental
pollution caused by the intensive use of agrochemicals, are among
the most pressing issues concerning agriculture sustainability. Biodiversity loss due to land use change and emission of greenhouse
gasses from agricultural activities are also causes for concern. A number of alternative agricultural practices are also presented
that can help to make agriculture less environmentally damaging
by reducing the use of natural resources, limiting inputs and preserving soil fertility and biodiversity. We think that there is room
for a different and more ecological agriculture and that research
should be implemented in order to better assess the potential and
constraints of the different options. However, notwithstanding the
great achievements of the “Green Revolution,” the world will need
70 to 100% more food by 2050. So a new challenge lies ahead: how
to feed nine billion with less land, water and energy, while at the
same time preserving natural resources and soil fertility? Technical advances are important in order to meet the future needs, but
addressing key socioeconomic issues, such as the inequality in the
access to resources, population growth, and access to education
are also a priority if we want to properly deal with sustainability.
It may require our society to change some of its paradigms and
“values” if we wish to preserve our support system, the soil and its
health, for the future generations
Environmental impact of different agricultural management practices: Conventional vs. organic agriculture
No full textOrganic agriculture refers to a farming system that enhance
soil fertility through maximizing the efficient use of local resources,
while foregoing the use of agrochemicals, the use of Genetic Modified Organisms (GMO), as well as that of many synthetic compounds used as food additives. Organic agriculture relies on a
number of farming practices based on ecological cycles, and aims
at minimizing the environmental impact of the food industry, preserving the long term sustainability of soil and reducing to a minimum the use of non renewable resources. This paper carries out a
comparative review of the environmental performances of organic
agriculture versus conventional farming, and also discusses the dif-
ficulties inherent in this comparison process. The paper first provides an historical background on organic agriculture and briefly
reports on some key socioeconomic issues concerning organic farming. It then focuses on how agricultural practices affect soil characteristics: under organic management soil loss is greatly reduced
and soil organic matter (SOM) content increases. Soil biochemical
and ecological characteristics appear also improved. Furthermore,
organically managed soils have a much higher water holding capacity than conventionally managed soils, resulting in much larger
yields compared to conventional farming, under conditions of water scarcity. Because of its higher ability to store carbon in the
soil, organic agriculture could represent a means to improve CO2
abatement if adopted on a large scale. Next, the impact on biodiversity is highlighted: organic farming systems generally harbor
a larger floral and faunal biodiversity than conventional systems,
although when properly managed also the latter can improve biodiversity. Importantly, the landscape surrounding farmed land also
appears to have the potential to enhance biodiversity in agricultural areas. The paper then outlines energy use in different agricultural settings: organic agriculture has higher energy efficiency
(input/output) but, on average, exhibits lower yields and hence reduced productivity. Nevertheless, overall, organic agriculture appears to perform better than conventional farming, and provides
also other important environmental advantages, such as halting the
use of harmful chemicals and their spread in the environment and
along the trophic chain, and reducing water use. Looking at the
future of organic farming, based on the findings presented in this
review, there is clearly a need for more research and investment
directed to exploring potential of organic farming for reducing
the environmental impact of agricultural practices; however, the
implications of reduced productivity for the socioeconomic system
should also be considered and suitable agricultural policies should
be developed
Biofuels: Efficiency, Ethics, and Limits to Human Appropriation of Ecosystem Services
No full textBiofuels have lately been indicated as a promising source of cheap and sustainable energy. In this paper we argue that some important ethical and environmental issues have also to be addressed: (1) the conflict between biofuels production and global food security, particularly in developing countries, and (2) the limits of the Human Appropriation of ecosystem services and Net Primary Productivity. We warn that large scale conversion of crops, grasslands, natural and semi-natural ecosystem, (such as the conversion of grasslands to cellulosic ethanol production, or plantation of sugar cane and palm oil), may have detrimental social and ecological consequences. Social effects may concern: (1) food security, especially in developing countries, leading to an increase of the price of staple food, (2) transnational corporations and big landowners establishing larger and larger landholdings in conflict with indigenous areas and the subsistence of small farmers. Ecological effects may concern: (1) competition with grazing wild and domesticated animals (e.g., millions of grazing livestock in USA prairies), (2) an excessive appropriation of Net Primary Production from ecosystems, (3) threatening biodiversity preservation and soil fertility. We claim that is it well known how ecological and social issues are strictly interwoven and that large scale biofuels production, by putting high pressure on both fronts, may trigger dangerous feedbacks, also considering the critical fact that 9 billion people are expected to inhabit the planet by 2050. There is a need to conduct serious and deep analysis on the environmental and social impact of large scale biofuels production before important energy policies are launched at global level. Biofuels will not represent an energetic panacea and their role in the overall energy consumption will remain marginal in our present highly energivorous society, while their effect on food security and environment preservation may have detrimental results. We should also have the courage to face two key issues: (1
- …
