1,659 research outputs found
Effects of organic fertilisers and compost extracts on organic tomato production
The effects of various fertilizers and different compost extracts on crop health and tomato yield were studied in the field in 2004–2005 in two locations in Iran. Treatments included different fertilizers (cattle, sheep and chicken manures, green waste and household composts and chemical fertilizers) and five aqueous extracts (from cattle manure, chicken manure, green-waste and house-hold composts and water as control). The effect of fertilizer type on tomato yield was significant in both locations (P < 0.05). Organic fertilizer use did not obtain higher yields compared to using chemical fertiliser. Generally, chicken manure and green-waste compost led to the highest and lowest tomato yield among different organic fertilizers, respectively. The effect of aqueous extracts was not significant on either crop health or tomato yield with these results were being very limited and inconsistent. Improved efficacy of acceptable alternatives to agrochemicals, especially in organic farming, is required
Inclusion Matrices and Chains
Given integers , , and such that , let
be the inclusion matrix of -subsets vs. -subsets of a
-set. We modify slightly the concept of standard tableau to study the notion
of rank of a finite set of positive integers which was introduced by Frankl.
Utilizing this, a decomposition of the poset into symmetric skipless
chains is given. Based on this decomposition, we construct an inclusion matrix,
denoted by , which is row-equivalent to . Its Smith
normal form is determined. As applications, Wilson's diagonal form of
is obtained as well as a new proof of the well known theorem on the
necessary and sufficient conditions for existence of integral solutions of the
system due to Wilson. Finally we present anotherinclusion
matrix with similar properties to those of which is in some
way equivalent to .Comment: Accepted for publication in Journal of Combinatorial Theory, Series
On the volumes and affine types of trades
A -trade is a pair of disjoint collections of subsets
(blocks) of a -set such that for every , any -subset of
is included in the same number of blocks of and of . It follows
that and this common value is called the volume of . If we
restrict all the blocks to have the same size, we obtain the classical
-trades as a special case of -trades. It is known that the minimum
volume of a nonempty -trade is . Simple -trades (i.e., those
with no repeated blocks) correspond to a Boolean function of degree at most
. From the characterization of Kasami--Tokura of such functions with
small number of ones, it is known that any simple -trade of volume at most
belongs to one of two affine types, called Type\,(A) and Type\,(B)
where Type\,(A) -trades are known to exist. By considering the affine
rank, we prove that -trades of Type\,(B) do not exist. Further, we derive
the spectrum of volumes of simple trades up to , extending the
known result for volumes less than . We also give a
characterization of "small" -trades for . Finally, an algorithm to
produce -trades for specified , is given. The result of the
implementation of the algorithm for , is reported.Comment: 30 pages, final version, to appear in Electron. J. Combi
Effect of different dietary levels of plant protein on growth indexes of white Leg shrimp
The influence of different dietary levels of plant protein (30, 50 and 70%) on growth indices of White Leg Shrimp (Litopenaeus vannamei) fed with an original 38 percent protein was assessed and compared with that of the commercial shrimp diet. The average weight gain at the end of the culture period in treatment 1 (30% plant protein and 70% animal protein), was 5.89 plus or minus 0.06 grams, for treatment 2 (50% plant protein and 50% animal protein), was 6.22 plus or minus 0.25 grams, for treatment 3 (70% plant protein and 30% animal protein), was 6.19 plus or minus 0.24 grams and for the control treatment (20% plant protein and 80% animal protein), was 6.42 plus or minus 0.40 grams. Our study of the influence of experimental and control diets on growth indices including growth rate (GR), food conversion ratio (FCR), protein efficiency ratio (PER), specific growth rate (SGR), and average daily gain (ADG), demonstrated that the indices were better in the control compared to the treatments. No significant difference was found among the treatments and between the treatments and the control for the indices (P>0.05). The percent of net protein utilization (NPU) in treatment 1 was significantly more than other treatments (P<0.05). We also found that the application of diets containing 50% plant protein (with 20% soybean meal) and 70% plant protein (with 41.72% soybean meal) can decrease diet costs. Cost of one kilogram of pellet in treatments 1, 2, 3 were 83.3%, 68.3% and 53.3% lower than the control diet respectively. Decrease of cost in treatment 2 and 3, in comparison to control in terms of lowering shrimp production cost is very important
A pedagogical introduction to the Slavnov formulation of quantum Yang-Mills theory
Over the last few years, Slavnov has proposed a formulation of quantum
Yang-Mills theory in the Coulomb gauge which preserves simultaneously manifest
Lorentz invariance and gauge invariance of the ghost field Lagrangian. This
paper presents in detail some of the necessary calculations, i.e. those dealing
with the functional integral for the S-matrix and its invariance under shifted
gauge transformations. The extension of this formalism to quantum gravity in
the Prentki gauge deserves consideration.Comment: 16 pages, review pape
Catecholamines are active plant-based drug compounds in Pisum sativum, Phaseolus vulgaris and Vicia faba Species
Introduction: Catecholamines (L-DOPA and dopamine) are the key metabolites found in nervous system and their endogenous deficiency is associated with different patho-physiological disorders. Therefore, it is important to screen the new herbal sources of catecholamines for drug preparation. In this study, the amount of L-DOPA and dopamine were investigated in the leaves and roots of three species from legume family such as Pisum sativum (garden pea), Phaseolus vulgaris (haricot bean) and Vicia faba (broad bean); using TLC and HPLC. Methods: The seeds of P. sativum, P. Vulgaris and V. faba were treated and cultured under the glasshouse conditions. The extraction from 1 gram of each plant sample was obtained and assayed for L-DOPA and dopamine using thin layer chromatography (TLC) and reversed-phase HPLC. Results: The results indicated that all cultivars accumulated different levels of L-DOPA and dopamine in leaves and roots. The quantitative results showed that the metabolites concentrations were high in the leaves of P. Sativum and V. faba compared to that in roots. Conclusion: The present study may provide a new avenue for preparation and estimation of L-DOPA and dopamine from plant sources and may be used for further analysis and therapeutic studies.</p
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