85 research outputs found
L'immixtion et la trop grande expertise du propriétaire, cause d'exonération de responsabilité des architectes et des entrepreneurs sous l'article 1688 C.C.
In May 1977, the Supreme Court of Canada gave an authoritative judgment on the interpretation of article 1688 of the Civil Code dealing with the liability of the builder and the architect. In Davie Shipbuilding Ltd v. Cargill Grain Company Ltd and The Foundation Company of Canada Ltd, the court established a new method of rebutting the presumption of liability resulting from the article. Indeed, the Supreme Court found that where the owner intervened during the construction and was more qualified than the contractors in charge of the work to judge its quality, he could not invoke the presumption resulting from article 1688 C.C. and was responsible for any loss. The case is not an easy one — questions of law and facts are not simple in this dispute involving more than eleven million dollars
Electrically charged regular black holes in nonlinear electrodynamics: light rings, shadows, and gravitational lensing
Within nonlinear electrodynamics (NED), photons follow null geodesics of an effective geometry, which
is different from the geometry of the spacetime itself. Over the last years, several works were dedicated to
investigate the motion of photons in the effective geometry of NED-based magnetically charged regular black
hole (RBH) solutions. However, there are few works considering electrically charged RBHs. We study the light
rings, shadows, and gravitational lensing of the electrically charged RBH solution proposed by Irina Dymnikova
(ID), which is a static and spherically symmetric spacetime with a NED source. We show that the shadow
associated to the effective geometry can be almost 10% bigger that the one associated to the standard geometry.
We also find that the ID solution may mimic the shadow properties of the Reissner-Nordstrom (RN) BH, for low- ¨
to-extreme values of the electric charge. Besides that, by using the backwards ray-tracing technique, we obtain
that ID and RN BH solutions can have a very similar gravitational lensing, for some values of the correspondent
electric charges. We also show that the motion of photons in the effective geometry can be interpreted as a
non-geodesic curve submitted to a 4-force term, from the perspective of an observer in the standard geometry.publishe
Tachigali rodolfo-rocioii, una nueva especie arbórea de Leguminosae de los bosques Andino Amazónicos de Perú
Como resultado de los esfuerzos de la sinergia entre la taxonomía y ecología en los estudios del género Tachigali Aubl. (Caesalpinioideae, Leguminosae), se describe e ilustra a la nueva especie Tachigali rodolfo-rocioii, proveniente de los bosques húmedos Amazónicos del sur y centro de Perú. Se compara y discute con las especies morfológicamente más próximas T. amarumayu y T. prancei
PRODUCTIVITY OF MINISTUMPS AND ROOTING OF MINICUTTINGS OF HYBRIDS OF Eucalyptus globulus LABILL IN RESPONSE TO NITROGEN
The aim of this study was to evaluate the productivity of ministumps
and the rooting of minicuttings from hybrid clones of Eucalyptus
globulus in response to nitrogen concentrations in nutritive solution,
in a fertirrigation system. To do so, we used five clones, namely: two
of Eucalyptus urophylla x Eucalyptus globulus (C-04 and C-16); two of
Eucalyptus grandis x Eucalyptus globulus (C-26 and C-30) and one of
Eucalyptus urophylla x Eucalyptus grandis (1213) as a comparator. Five
N concentrations were tested (36, 72, 109, 164 and 218 mg L-1) in a
statistical design of randomized blocks on a split plot arrangement
with three replications. Six months after the implementation, using
standard nutritive solution, in fertirrigation system, the treatment
application began. After 30 days, it began the weekly harvest of
minicuttings and the cutting plantion at every 15 days, during 90 days.
It was evaluated the survival and the productivity of the ministumps
and, regarding the minicuttings, it was observed: the survival, the
rooting percentage, the minicutting percentage with visible roots at
the lower end of the tube, having these 10cm, after 30 days in the
greenhouse. It was found that there is a significant effect of N
concentration over the monthly productivity of ministumps from clones
C-16 (169.05 mg L-1), C-26 (146.67 mg L-1) and for C-04 and 1213,
(positive linear effect). However, no significant effect of dose was
observed for the percentage of visible roots at the lower end of the
tube, rooting and survival of cuttings at thirty days in the
greenhouse.O objetivo deste trabalho foi avaliar a produtividade de minicepas e o
enraizamento de miniestacas de clones h\uedbridos de Eucalyptus
globulus em resposta a concentra\ue7\uf5es de nitrog\ueanio em
fertirriga\ue7\ue3o de minijardim clonal. Para isso, utilizaram-se
cinco clones, sendo: dois clones de Eucalyptus urophylla x Eucalyptus
globulus (C-04 e C-16); dois clones de Eucalyptus grandis x
Eucalyptus globulus (C-26 e C-30) e um clone de Eucalyptus urophylla x
Eucalyptus grandis (1213) como refer\ueancia. Foram testadas cinco
concentra\ue7\uf5es de N (36, 72, 109, 164 e 218 mg L-1) no arranjo
de parcelas subdivididas com tr\ueas repeti\ue7\uf5es, em
delineamento estat\uedstico de blocos ao acaso. Seis meses ap\uf3s
a implanta\ue7\ue3o do minijardim, utilizando solu\ue7\ue3o
nutritiva padr\ue3o, em sistema de fertirriga\ue7\ue3o,
aplicaram-se os tratamentos por 30 dias, quando iniciaram-se as coletas
das miniestacas semanalmente e o estaqueamento a cada 15 dias, durante
90 dias. Avaliou-se a sobreviv\ueancia e produtividade das minicepas
e a sobreviv\ueancia das miniestacas, porcentagem de enraizamento e
porcentagem de miniestacas com ra\uedzes vis\uedveis na extremidade
inferior do tubete. Verificou-se a exist\ueancia de efeito
significativo das concentra\ue7\uf5es de nitrog\ueanio para
produtividade mensal das minicepas dos clones C-16 (169,05 mg L-1),
C-26 (146,67 mg L-1) e para C-04 e 1213, efeito linear positivo.
Entretanto, n\ue3o foi observado efeito significativo das
concentra\ue7\uf5es para a percentagem de miniestacas com
ra\uedzes vis\uedveis na extremidade inferior do tubete,
enraizamento e sobreviv\ueancia das miniestacas aos trinta dias em
casa de vegeta\ue7\ue3o
Sinopsis taxonómica, ecológica y etnobotánica del género Tachigali Aubl. (Leguminosae) en la región del Cusco, Perú
Se da a conocer la sinopsis taxonómica, etnobotánica y ecológica del género Tachigali Aubl. (Leguminosae), en la región del Cusco. Los resultados revelan la presencia de nueve especies: Tachigali chrysaloides, T. guianensis, T. macbridei, T. paniculata, T. setifera, T. vasquezii y otras tres morfoespecies. Todas presentan su distribución restringida al bosque amazónico húmedo lluvioso y al bosque amazónico húmedo pre-montano. La mayoría de especies son aprovechadas para el comercio de madera y como combustible. Se propone incluir dentro de las categorías de amenaza a cuatro especies con preocupación menor (LC), tres como casi amenazada (NT) y dos como vulnerables (VU). La riqueza de este género en el Cusco es comparable a otras regiones de alta diversidad y endemismo como Loreto en Perú y el bioma de la Mata Atlántica en Brasil, que supera ampliamente en extensión territorial a la región del Cusco
Macronutrients in production of Peltophorum dubium (Spreng.) Taub. seedlings in red yellow ultisol of the Zona da Mata, MG region
O objetivo deste trabalho foi avaliar o efeito de doses de
macronutrientes sobre o crescimento e os \uedndices de qualidade de
mudas de canaf\uedstula e determinar a dose recomendada dos mesmos
para estabelecer um adequado programa de aduba\ue7\ue3o. No
trabalho, conduzido em casa de vegeta\ue7\ue3o, utilizou-se
amostras de Argissolo Vermelho Amarelo, retirado da camada abaixo de 20
cm de profundidade, como substrato. Delimitou-se o experimento por meio
de matriz baconiana, avaliando-se tr\ueas doses dos seis
macronutrientes (nitrog\ueanio, f\uf3sforo, pot\ue1ssio,
c\ue1lcio, magn\ue9sio e enxofre) e dois tratamentos adicionais, um
com doses de refer\ueancia e outro sem adi\ue7\ue3o de
nutrientes. Adotou-se o delineamento inteiramente casualizado com
quatro repeti\ue7\uf5es. Foram analisados os par\ue2metros
morfol\uf3gicos e os \uedndices de qualidade de mudas.
Verificou-se, atrav\ue9s de an\ue1lise dos contrastes ortogonais,
resposta significativa de todas as vari\ue1veis estudadas \ue0
aplica\ue7\ue3o dos macronutrientes, exceto para a
rela\ue7\ue3o altura di\ue2metro (H/D) nos tratamentos com P, Ca
e S. N\ue3o foi verificada resposta \ue0 aplica\ue7\ue3o de Ca
para a maioria das caracter\uedsticas avaliadas, com
exce\ue7\ue3o das rela\ue7\uf5es altura de parte a\ue9rea por
peso de mat\ue9ria seca de parte a\ue9rea (H/MSPA) e peso de
mat\ue9ria seca de parte a\ue9rea por peso de mat\ue9ria seca de
raiz (MSPA/MSR). Recomenda-se a aplica\ue7\ue3o de 600 mg dm-3 de
P, 150 mg dm-3 de K, 0,50 cmolc dm-3 de Mg e 50 mg dm-3 de S, e
sugerem-se novos estudos com os nutrientes N e Ca, para a
produ\ue7\ue3o de mudas de canaf\uedstula, usando a camada abaixo
de 20 cm de profundidade de Argissolo Vermelho Amarelo como substrato.The objective of this work was to evaluate the effect of macronutrients
doses upon the growth and quality indices of Peltophorum dubium
seedlings and to determine the recommended doses for them to establish
a suitable fertilization program. In the paper, carried out in a
greenhouse, samples of \u2018Red Yellow Ultisol\u2019 were used,
removed from the layer below, 20 cm deep, as a substratum. The
experiment was designed in a Baconian Matrix, and three doses of the
six macronutrients (nitrogen, phosphorus, potassium, calcium, magnesium
and sulfur) and two additional treatments were evaluated, one with
reference doses and the other one without the addition of nutrients.
The entirely casual design was adopted, with four repetitions. The
morphologic parameters and quality indices of seedlings were analyzed.
Through the orthogonal contrasts, a significant response of all the
variables studied was verified related to the macronutrient applied,
except for the relation height/diameter (H/D) in the treatments with
Ca, P and S. It was not verified response to Ca application for most
characteristics evaluated, unless for the relation of the aerial part
height per aerial part dry weight (H/MSPA) and aerial part dry weight
per root dry weight (MSPA/MSR). The recommended doses were of 600 mg
dm-3 of P, 150 mg dm-3 of K, 0,50 cmolc dm-3 of Mg and 50 mg dm-3 of S.
Based on this work, further studies are suggested with N and Ca, for
seedlings production of the studied species using from the layer below
20 cm deep of the \u2018Red Yellow Ultisol\u2019 as the substratum
Response of Senna macranthera seedlings grown in Red Yellow Argisol to macronutrients
Senna macranthera tem grande ocorr\ueancia natural, com potencial
uso na recupera\ue7\ue3o de \ue1reas degradadas. Entretanto,
existe necessidade de informa\ue7\uf5es sobre a nutri\ue7\ue3o
das esp\ue9cies florestais nativas. Assim, o objetivo deste trabalho
foi avaliar o efeito de doses de N, P, K, Ca, Mg e S sobre o
crescimento e \uedndices de qualidade de mudas de fedegoso e
determinar a dose a ser recomendada para estes. No trabalho, conduzido
em casa de vegeta\ue7\ue3o, utilizou-se amostras de Argissolo
Vermelho Amarelo, retirado da camada abaixo de 20 cm de profundidade,
como substrato. Delimitou-se o experimento por meio de matriz
baconiana, avaliando-se tr\ueas doses dos seis macronutrientes e dois
tratamentos adicionais, um com doses de refer\ueancia
(aduba\ue7\ue3o usada como padr\ue3o para esp\ue9cies nativas)
e outro sem adi\ue7\ue3o de nutrientes. Adotou-se o delineamento
inteiramente casualizado com quatro repeti\ue7\uf5es. Foram
analisados os par\ue2metros morfol\uf3gicos e os \uedndices de
qualidade de mudas. Verificou-se, por meio de an\ue1lise dos
contrastes ortogonais, resposta significativa de todas as
vari\ue1veis estudadas \ue0 aplica\ue7\ue3o dos
macronutrientes. A esp\ue9cie mostrou-se mais exigente em P e K em
compara\ue7\ue3o aos demais macronutrientes, sendo recomendada dose
de 600 mg dm-3 de P e 200 mg dm-3de K. Recomendam-se estudos adicionais
com os nutrientes N, Ca, Mg e S, com doses inferiores \ue0s menores
doses testadas, tendo em vista que, segundo dados deste estudo, as
melhores doses desses nutrientes se encontram entre os teores originais
do solo usado como substrato e as menores doses aplicadas.Senna macranthera has great natural occurrence, with potential use in
the recovery of degraded areas. However, there is need for information
on the nutrition of native forest species. In that sense, the
objectives of this study were to evaluate the effect of doses of N, P,
K, Ca, Mg and S on growth and quality indices of seedlings of Senna
macranthera and to determine their recommended doses. This study was
carried out in a greenhouse, using a Red Yellow Argisol, removed from
the layer below 20 cm depth, as substratum. The experiment was designed
in a Baconian Matrix, and three doses of the six macronutrients and two
additional treatments were evaluated, one with reference doses
(fertilizer used by default for native species) and the other one
without the addition of nutrients. An entirely casualized design was
adopted, with four repetitions. The morphologic parameters and quality
indices of seedlings were analyzed. Through orthogonal contrasts, a
significant response of all the variables studied was verified in
relation to the macronutrients applied. The species was most demanding
of P and K in comparison to the other macronutrients, and the
recommended doses were of 600 mg dm-3 of P and 200 mg dm-3 of K. It is
recommended that further studies with lower doses of the nutrients N,
Ca, Mg and S be carried out, since, according to this study, the best
doses for these nutrients were found for the original soil used as
substrate and the lowest dose of the applied treatment
The innovation of the symbiosome has enhanced the evolutionary stability of nitrogen fixation in legumes
Nitrogen-fixing symbiosis is globally important in ecosystem functioning and agriculture, yet the evolutionary history of nodulation remains the focus of considerable debate. Recent evidence suggesting a single origin of nodulation followed by massive parallel evolutionary losses raises questions about why a few lineages in the N2 -fixing clade retained nodulation and diversified as stable nodulators, while most did not. Within legumes, nodulation is restricted to the two most diverse subfamilies, Papilionoideae and Caesalpinioideae, which show stable retention of nodulation across their core clades. We characterize two nodule anatomy types across 128 species in 56 of the 152 genera of the legume subfamily Caesalpinioideae: fixation thread nodules (FTs), where nitrogen-fixing bacteroids are retained within the apoplast in modified infection threads, and symbiosomes, where rhizobia are symplastically internalized in the host cell cytoplasm within membrane-bound symbiosomes (SYMs). Using a robust phylogenomic tree based on 997 genes from 147 Caesalpinioideae genera, we show that losses of nodulation are more prevalent in lineages with FTs than those with SYMs. We propose that evolution of the symbiosome allows for a more intimate and enduring symbiosis through tighter compartmentalization of their rhizobial microsymbionts, resulting in greater evolutionary stability of nodulation across this species-rich pantropical legume clade
Influência da saturação por bases do substrato no crescimento e qualidade de mudas Machaerium nictitans (Vell.) Benth.
Expanding tropical forest monitoring into Dry Forests: The DRYFLOR protocol for permanent plots
This is the final version. Available on open access from Wiley via the DOI in this recordSocietal Impact Statement
Understanding of tropical forests has been revolutionized by monitoring in permanent plots. Data from global plot networks have transformed our knowledge of forests’ diversity, function, contribution to global biogeochemical cycles, and sensitivity
to climate change. Monitoring has thus far been concentrated in rain forests. Despite
increasing appreciation of their threatened status, biodiversity, and importance to the
global carbon cycle, monitoring in tropical dry forests is still in its infancy. We provide
a protocol for permanent monitoring plots in tropical dry forests. Expanding monitoring into dry biomes is critical for overcoming the linked challenges of climate change,
land use change, and the biodiversity crisis.Newton FundNatural Environment Research Council (NERC)Fundação de Amparo à Pesquisa do Estado de São PauloCYTE
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