10,347 research outputs found
Algebraic Aspects of Abelian Sandpile Models
The abelian sandpile models feature a finite abelian group G generated by the
operators corresponding to particle addition at various sites. We study the
canonical decomposition of G as a product of cyclic groups G = Z_{d_1} X
Z_{d_2} X Z_{d_3}...X Z_{d_g}, where g is the least number of generators of G,
and d_i is a multiple of d_{i+1}. The structure of G is determined in terms of
toppling matrix. We construct scalar functions, linear in height variables of
the pile, that are invariant toppling at any site. These invariants provide
convenient coordinates to label the recurrent configurations of the sandpile.
For an L X L square lattice, we show that g = L. In this case, we observe that
the system has nontrivial symmetries coming from the action of the cyclotomic
Galois group of the (2L+2)th roots of unity which operates on the set of
eigenvalues of the toppling matrix. These eigenvalues are algebraic integers,
whose product is the order |G|. With the help of this Galois group, we obtain
an explicit factorizaration of |G|. We also use it to define other simpler,
though under-complete, sets of toppling invariants.Comment: 39 pages, TIFR/TH/94-3
Critical Cooperation Range to Improve Spatial Network Robustness
A robust worldwide air-transportation network (WAN) is one that minimizes the
number of stranded passengers under a sequence of airport closures. Building on
top of this realistic example, here we address how spatial network robustness
can profit from cooperation between local actors. We swap a series of links
within a certain distance, a cooperation range, while following typical
constraints of spatially embedded networks. We find that the network robustness
is only improved above a critical cooperation range. Such improvement can be
described in the framework of a continuum transition, where the critical
exponents depend on the spatial correlation of connected nodes. For the WAN we
show that, except for Australia, all continental networks fall into the same
universality class. Practical implications of this result are also discussed
Biochemical genetic profile of the Indian mackerel Rastreliger kanagurta of mud bank and post-mud bank period
An attempt was made to study the genetic profile
of the Indian mackerel Rastrelliger kanagurta, an
economically important fish species of India. The
genetic profile of the mackerel caught during the
mud bank period was compared to that of the post
mud bank period
Biochemical genetic polymorphism in Indian mackerel (Rastrelliger kanagurta)
Six enzymes glucose 6 phosphate dehydrogenase (G6PD), xanthene de hydrogenase (XDH), alcohol dehydrogenase
(ADH), peroxidase (PO), lactate dehydrogenase (LDH) and isocitric dehydrogenase (lDH) were examined to discover the
genetic variation in Indian mackerel through polyacrylamide gel electrophoresis. A significant difference in allelic frequency at XDH locus was observed between the eachin and Thotapally populations. Thotapally stocks exhibited a significant
deviation (P< 0.05) from Hardy weinberg equillibrium. The proportion of polymorphic Joci was 0.777. The coefficient of
identity and the genetic distance estimated were 0.9262 and 0.076 respectively
Biochemical genetic polymorphism in the Indian mackerel Rastrelliger kanagurta from Mangalore region
Electrophoresis is the modern and most
popular technique used for studying the genetic
variability within and among the populations of
plants and animals. Genetically controlled tissue
enzymes are the most suitable parameters for
genetic variability studies. In the present study
Polyacrylamide Gel Electrophoresis was used to
study the genetic variability in Indian mackerel
Effect of FYM, foliar feeding of nitrogen and deficit irrigation on drip irrigated coriander (Coriandrum sativum L.)
A field experiment was conducted to study the water use, nitrogen (N) uptake and economics of coriander (Coriandrum sativum L.) under organic enrichment, foliar feeding of N and fertigation. Drip irrigation at 80% ETc + foliar spray of 25% N (15 kg ha-1) + fertigation (45 kg ha-1) gave the highest plant height, branch plant-1, umbel plant-1, umbelets umbel-1, seed umbel-1, and test weight compared to irrigation at 80% ETc and at 60% ETc (upto flowering stage) + 80% ETc (reproductive stage) with or without foliar spray. Increased yield parameters were attributed to the highest seed yield and B:C ratio of 1.90 using 265.74 mm water. Water use efficiency (WUE) was also the highest. This treatment also recorded the highest N uptake of 52.6 kg ha-1. Further, addition of 10 t ha-1 FYM in addition to recommended nitrogen dose (60 kg ha-1) gave higher yield attributes viz., branch plant-1, umbel plant-1, seed umbel-1 and test weight as compared to recommended level of fertilizers. Enhanced yield attributes thus increased seed yield, N removal, WUE and B:C ratio.
 
Knowledge And Opinion About Hiv/Aids Among Long Route Truck Drivers
A cross sectional study was carried out on 235 truck drivers operating at Kanpur- Jhansi highway to assess their knowledge and opinion about HIV/AIDS It was observed that about 73% had heard about HIV/AIDS. two third were aware about sexual transmission as the route of transmission. Televison was the main source of their knowledge (76.74%). But knowledge on other aspects of HIV was very less, only one-third were aware about preventive role of condom. Less than half (45.95%) were of the opinion that this disease can be prevented. It was dis heartening to note that (34.46%) were in favor to separate AIDS patient from family and (43.40%) were in favor todivorce spouse having AIDS. Withthis background of Knowledge about half of truck drivers (48.94%) were of the 
- …