17,213,333 research outputs found
Triatoma cavernicola Else, Cheong, Mahadevan and Zarate
No full textSpecies. T. cavernicola Else, Cheong, Mahadevan and Zárate Etymology. No etymological description is given in the paper (Else, Cheong, Mahadevan & Zárate 1977).Published as part of Gonçalves, Teresa Cristina Monte, Novo, Shênia Patrícia Corrêa, Lopes, Catarina Macedo & Santos-Mallet, Jacenir Reis Dos, 2009, Etymology of Triatomine Species (Hemiptera: Reduviidae: Triatominae), pp. 1-26 in Zootaxa 2148 on page 12, DOI: 10.5281/zenodo.18869
Dynamic Instability of a Growing Adsorbed Polymorphic Filament
No full textAbstractThe intermittent transition between slow growth and rapid shrinkage in polymeric assemblies is termed “dynamic instability”, a feature observed in a variety of biochemically distinct assemblies including microtubules, actin, and their bacterial analogs. The existence of this labile phase of a polymer has many functional consequences in cytoskeletal dynamics, and its repeated appearance suggests that it is relatively easy to evolve. Here, we consider the minimal ingredients for the existence of dynamic instability by considering a single polymorphic filament that grows by binding to a substrate, undergoes a conformation change, and may unbind as a consequence of the residual strains induced by this change. We identify two parameters that control the phase space of possibilities for the filament: a structural mechanical parameter that characterizes the ratio of the bond strengths along the filament to those with the substrate (or equivalently the ratio of longitudinal to lateral interactions in an assembly), and a kinetic parameter that characterizes the ratio of timescales for growth and conformation change. In the deterministic limit, these parameters serve to demarcate a region of uninterrupted growth from that of collapse. However, in the presence of disorder in either the structural or the kinetic parameter the growth and collapse phases can coexist where the filament can grow slowly, shrink rapidly, and transition between these phases, thus exhibiting dynamic instability. We exhibit the window for the existence of dynamic instability in a phase diagram that allows us to quantify the evolvability of this labile phase
The Pearl fish Carapus margaritiferae (Rendahl), a new record for the Indian waters
No full textIN a recent communication (Mahadevan 1959) attention was drawn to an interesting
association of the pearl fish Fierasfer homei (Richardson) with the wing mussel Pteria
sp.,** found in the Gulf of Mannar off Tuticorin. A re-examination of the pearl
fish showed that the position of the vent is at the base of a line just behind pectoral
origin and the origin of the dorsal is in a line above the middle of pectoral (Plate,
1, Fig. C). Further, other distinguishing characters of this fish described elsewhere
in this account justified the earlier doubts (Mahadevan op. cit.) of the likelihood
of its coming under Carapus (syn : Fierasfer) margaritiferae (Rendahl), a brief
account of which is given by de Beaufort (1951) based on specimens collected from
Pulu Punga, Pulu Missa, coast of Flores and Cape Jaubert N. W. Australia, mostly
in association with the wing mussel or sometimes with a holothurian. Smith (1955),
while reviewing the family Carapidae has mentioned the occurrence of C margaritiferae
in South African waters also where three specimens, 75-93 mm. in length, were
' taken from inside clams at Durban.' The data on two specimens of 63.5 and 85.0
mm. examined by the present author indicate differences in some of the characteristics
as compared with the South African form described by Smith. In order to facilitate
comparison of the Indian form with others occurring elsewhere a detailed
description of the material in hand is given below
Not Available
No full textNot AvailableIN a recent communication (Mahadevan 1959) attention was drawn to an interesting
association of the pearl fish Fierasfer homei (Richardson) with the wing mussel Pteria
sp., * * found in the Gulf of Mannar off Tuticorin. A re -examination of the pearl
fish showed that the position of the vent is at the base of a line just behind pectoral
origin and the origin of the dorsal is in a line above the middle of pectoral (Plate,
1, Fig. C). Further, other distinguishing characters of this fish described elsewhere
in this account justified the earlier doubts (Mahadevan op. cit.) of the likelihood
of its coming under Carapus (syn : Fierasfer) margaritiferae (Rendahl), a brief
account of which is given by de Beaufort (1951) based on specimens collected from
Pulu Punga, Pulu Missa, coast of Flores and Cape Jaubert N. W. Australia, mostly
in association with the wing mussel or sometimes with a holothurian. Smith (1955),
while reviewing the family Carapidae has mentioned the occurrence of C margaritiferae
in South African waters also where three specimens, 75 -93 mm. in length, were
' taken from inside clams at Durban.' The data on two specimens of 63.5 and 85.0
mm. examined by the present author indicate differences in some of the characteristics
as compared with the South African form described by Smith. In order to facilitate
comparison of the Indian form with others occurring elsewhere a detailed
description of the material in hand is given below.Not Availabl
jhe64/V1.0: PSOM v1.0-c He & Mahadevan experiments
No full textPSOM v1.0 with source code for He & Mahadevan (in prep
Pearl culture
No full textMost scientific studies on oyster resources, biology and farming have been carried out in the twentieth
century. New approaches to our understanding of the intricate pattern of the oyster behaviour in respect
of feeding, reproduction, larval development and disease control have enabled scientists to plan and undertake
highly successful oyster farming in recent years. This is not only the situation in advanced countries but
has become a distinct possibility in India. Scientists of the Central Marine Fisheries Research Institute
have achieved remarkable success by carrying out extensive investigations relating to the breeding and farming
of the edible oyster during the past one decade. In addition to the evaluation of the potentialities of natural
resources in several zones of Indian coastal waters, estuaries and backwaters, suitable technologies for oyster
farming and hatchery production of oyster seed have been developed by the CMFRI. It would only be a
matter of time before commercial farming of the edible oyster takes place in the country
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