2,569 research outputs found
The Shield that Never Was: Societies with Single-Peaked Preferences are More Open to Manipulation and Control
Much work has been devoted, during the past twenty years, to using complexity
to protect elections from manipulation and control. Many results have been
obtained showing NP-hardness shields, and recently there has been much focus on
whether such worst-case hardness protections can be bypassed by frequently
correct heuristics or by approximations. This paper takes a very different
approach: We argue that when electorates follow the canonical political science
model of societal preferences the complexity shield never existed in the first
place. In particular, we show that for electorates having single-peaked
preferences, many existing NP-hardness results on manipulation and control
evaporate.Comment: 38 pages, 2 figure
Exotic medicinal plants from West Vidarbha region - V
Exotics are those plants which are migrated from one region to other region. They are also known as immigrants. Such a plants are now a days considered as a part of forest vegetation because they mixed with the natural floras. About 40% exotics are found in a indigenous floras, their exact time of arrival is different. Some of the plants are migrated from cultivated field or garden due to careless attention. These are considered as naturalized aliens. The present work deals with the report of 26 medicinally important exotics from Vidarbha region
A role of Immigrants and Indigenous plants in forest improvement from West Vidarbha region
Present investigation deals with the report of immigrants and indigenous plant that improves the forest vegetation as well as balancing an environment from west vidarbha region of Maharashtra state. In all a list of 75 immigrants and 51 indigenous plants. Thus a list of 126 plants with their role is described
Diversity of ornamental trees from Amravati city of West Vidarbha region
The present study deals with the diversity of ornamental trees from Amravati District of West Vidarbha region of Maharashtra. All these ornamental trees show diversity in their habitat, floral structure, flowering period, etc. In the present investigation, extensive field surveys were conducted in the different localities of Amravati district during 2005-2011containing description, distribution, origin, vegetative and flowering period of 25 ornamental trees species from 19 families with their photographs and preserved as Herbaria
Qualitative phytochemical screening of indian witchweed: Striga asiatica (L.) O. Ktze - an unexplored medicinal parasitic plant
Many herbal remedies have been employed in various medical systems for the treatment of different diseases. The parasitic plant Striga asiatica (L.) O. Ktze commonly known as witch weed belongs to family Scrophulariaceae has been used in different system of traditional medicine for curing various diseases and ailments of human beings. The present study deals with the qualitative phytochemical screening of Striga asiatica (L.) O. Ktze of whole plant powder in six different extracts (i.e. petroleum ether, benzene, chloroform, acetone, ethanol and water). The extracts showed the prominently presence of phytoconstituents like carbohydrates, cardiac glycosides, alkaloids, flavonoids, tannin, phenolics, steroids, coumarins and saponin. However anthroquinone glycosides and quinone are totally absent in all extracts. Most of the phytoconstituents from Striga asiatica (L.) O. Ktze lacks the reports of pharmacological activities, which support its further pharmacological studies
Preliminary phytochemical investigation of Combretum albidum G. Don; An ignored medicinally important liana.
Day by day faith of people on herbal medicine is increases due to the side effect of synthetic drugs, and results into people started looking back to the traditional knowledge of plant for their health care in day to day life. Certain local practitioner, traditional healers uses the decoction of the fruit of Combretum albidum G. Don in the treatment of diarrhoea and dysentery, stem barks used in jaundice. So the present study deals with preliminary phytochemical analysis of stem, leaf, flower and fruit using six different solvent. It needful helps for the scientific documentation and standardization of row plant material used in medicine and its worldwide acceptance. 
The chiral and flavour projection of Dirac-Kahler fermions in the geometric discretization
It is shown that an exact chiral symmetry can be described for Dirac-Kahler
fermions using the two complexes of the geometric discretization. This
principle is extended to describe exact flavour projection and it is shown that
this necessitates the introduction of a new operator and two new structures of
complex. To describe simultaneous chiral and flavour projection, eight
complexes are needed in all and it is shown that projection leaves a single
flavour of chiral field on each.Comment: v2: 17 pages, Latex. 5 images eps. Added references, reformatted and
clarification of some point
Phytochemical screening of some Euphorbiaceae members
The present investigation includes the Phytochemical screening of some medicinally important plants from the family Euphorbiaceae. All the members studied are exotic but naturalized except Ricinnus communis L. which is commercially cultivated in India. Plant extracts were prepared in various solvents and phytochemically they were tested in the solvent where the good extraction or active extraction observed, Phytochemical tests were carried out specially for screening secondary metabolites from the selected exotic medicinal plants from family Euphorbiaceae. Six genera and seven species of Euphorbiaceae were phytochemically analyzed to find secondary metabolites. Ă‚
Recursive Construction of Generator for Lagrangian Gauge Symmetries
We obtain, for a subclass of structure functions characterizing a first class
Hamiltonian system, recursive relations from which the general form of the
local symmetry transformations can be constructed in terms of the independent
gauge parameters. We apply this to a non-trivial Hamiltonian system involving
two primary constraints, as well as two secondary constraints of the Nambu-Goto
type.Comment: 10 pages, Late
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