Studies on lipolytic bacteria in stored fish Etroplus suratensis (Bloch)

The distribution of total hectrotrophic bacteria (THB) and lipolytic bacteria in various regions (body surface, gill, intestine and flesh) of fish Etroplus suratensis (Bloch) during storage at 28 ± 2°C and 4°C was studied. Pseudomonas dominated at reduced temperature whereas at 28 ± 2°C and in fresh condition Vibrio, Aeromonas, and Acinetobacter dominated. Lipolytic activity was elaborated by the members of various genera and their activity varied in different lipid compounds (tributyrin, tween 80, tween 60, tween 40 and tween 20). Tributyrin was utilized by majority of the isolates. All the selected isolates preferred a temperature of 35°C and pH 6.0 for their maximum growth. Aeromonas and Vibrio showed maximum growth at 0.5% NaCl concentration while 3% NaCl was found to be optimum for Pseudomonas

Injuries to the great vessels: an autopsy-based study

Background: Injuries of the chest causing disruption of the thoracic cage, damaging the great vessels are increasing daily. Aorta is most vulnerable to injury in deceleration trauma from road and air accidents, fall from height and penetrating injuries. Incidence of traumatic rupture of the aorta is rising with higher travel speed.  Methods: In this study we analysed the pattern of injury to great vessels and the socio-demographic pattern of the victims in trauma. 250 cases brought to a tertiary care institution for autopsy were studied from 1st January 2005 to 30th November 2005 (1st July 2005 - 30th November prospectively, and 1st January - 30th June 2005, retrospectively). A cross sectional study design including all cases of trauma to the chest was done with consecutive sampling. Data was collected in pro forma and analysed.Results: 206 victims were males. Commonest cause of chest injury was trauma. 130 (52%) were victims of road traffic accidents and the vehicle implicated the most was bus (41 cases, 16.4%). Pedestrians constituted the majority (26.4%). 15 cases (6%) involved major blood vessels of the thorax. Descending part of the thoracic aorta was vulnerable, with transection of the great vessels in 5 cases (2%). Haemothorax was observed in 102 cases on right side and 94 cases on the left side. 9 cases (4%) of bronchial or tracheal ruptures with 6 cases of severance and 3 incidences of tear were recorded.Conclusions: The wound of aorta or pulmonary artery are immediately fatal and commonly seen in case of vehicular accident or fall from height due to the intense compression to the chest with or without any sign of external injury. Most ruptures are due to automobile accidents and the mechanism of injury is sudden motion of the heart and great vessels

An adaptive delayed acknowledgment strategy to improve TCP performance in multi-hop wireless networks.

In multi-hop wireless networks, transmission control protocol (TCP) suffers from performance deterioration due to poor wireless channel characteristics. Earlier studies have shown that the small TCP acknowledgments consume as much wireless resources as the long TCP data packets. Moreover, generating an acknowledgment (ACK) for each incoming data packet reduces the performance of TCP. The main factor affecting TCP performance in multi-hop wireless networks is the contention and collision between ACK and data packets that share the same path. Thus, lowering the number of ACKs using the delayed acknowledgment option defined in IETF RFC 1122 will improve TCP performance. However, large cumulative ACKs will induce packet loss due to retransmission time-out at the sender side of TCP. Motivated by this understanding, we propose a new TCP receiver with an adaptive delayed ACK strategy to improve TCP performance in multi-hop wireless networks. Extensive simulations have been done to prove and evaluate our strategy over different topologies. The simulation results demonstrate that our strategy can improve TCP performance significantly

Heavy metal resistant bacteria associated with the black clam Villorita cyprinoides var cochinensis (Hanley) and water collected from Cochin backwater

A total of 147 strains of heterotrophic bacteria, isolated from water and the black clam Villorlia cyprinoides var conchinensis from Cochin backwater were subjected to heavy metal sensitivity tests for five heavy metals viz. mercury. zinc, cadmium, copper and lead. In general, the isolates from water showed higher resistance towards the heavy metals. Members of all the genera except Coryneform group showed similar trend of resistance. The strains of Coryneform group isolated from animals were more resistant than their counterparts isolated from water. Minimum inhibitory concentration (MIC) of the metals varied. It may be concluded from the results that the habitat of the organisms plays a unique role in the ecology of heavy metal resistant bacteria

Studies on the effect of the organophosphorus pesticide Eka(Rlu) x EC 25 on the bacterial flora of Villorita cyprinoides var. cochinensis (Han1ey)

The thesis is Studies on the Effect or the Obganophosphorus Pesticide Ekalux(R) EC 25 on the Bacterial Flora or Villorita Cyprinoides Var.Cochinensis (Hanley). For the present investigation, the black clam Villorita gyprinoides var. cochinensis (Hanley), a most common clam genus present in this estuarine system has been selected as test organaism and Ekalux (R) EC 25 as toxicant. The aspects dealt with are 1. Total heterotrophic bacterial population, 2. Generic composition, 3. Hydrolytic enzyme producing bacteria, 4. Antibiotic resistance, 5. Heavy metal resistance, 6. The effect of pesticide concentration on the growth of the bacteria and 7. Effect of temperature, pH and sodium chloride on the growth and phosphate release of selected isolates.The samples for the experiment were collected from the Vembanad Lake, near Kumbalam Island during the period of September 1985 to May '86. The THB of the estuarine water and clams contained 6.5 x I04/ml and 2.975 x l06/g respectively, immediately after collection. Untreated water and clam samples showed enormous increase in THB from 0 hr population. The treated samples (water and clams) contained higher THB than 0 hr. In general, THB was observed to increase tremendously in the samples treated with pesticide when compared to their native flora. With reference to various concentrations of pesticides, THB recorded an increase with increase of concentration in water and clam samples.Cochin University of Science and TechnologySchool of Marine Sciences, Cochin University of Science and Technolog

Not Available

Not AvailableA total of 147 strains of heterotrophic bacteria, isolated from water and the black clam Villorlia cyprinoides var conchinensis from Cochin backwater were subjected to heavy metal sensitivity tests for five heavy metals viz. mercury. zinc, cadmium, copper and lead. In general, the isolates from water showed higher resistance towards the heavy metals. Members of all the genera except Coryneform group showed similar trend of resistance. The strains of Coryneform group isolated from animals were more resistant than their counterparts isolated from water. Minimum inhibitory concentration (MIC) of the metals varied. It may be concluded from the results that the habitat of the organisms plays a unique role in the ecology of heavy metal resistant bacteria.Not Availabl

PbS Nanoparticles in Polyacrylamide Matrix: Structure, Optical Properties and Influence on the Host Polymer

A synthetic procedure for the incorporation of PbS nanoparticles in a polyacrylamide (PAM) matrix was introduced. The method is based on the simultaneous polymerization of the monomer and thermal decomposition of the dithiooxamide-lead complex. XRD analysis revealed that PbS nanoparticles have a sphalerite crystal structure (galena). The TEM micrograph showed spherical particles, with average diameter of about 3 nm, well dispersed in the polymer matrix. Although a sharp edge was not observed, the optical absorption of the PAM-PbS nanocomposite is shifted towards lower wavelengths compared to the bulk PbS.SFKM 2004 : September 20–23, 2004, Sokobanja

Study of sago starch-CdS nanocomposite films: Fabrication, structure, optical and thermal properties

A synthetic procedure for the preparation of nanocomposite films of sago starch and CdS nanoparticles was introduced. The films were characterized using optical, structural, and thermal techniques. The formation of nanostructured CdS in the starch matrix was confirmed by a blue shift in the onset of absorption in the UV-VIS spectra of the nanocomposites. The average size of the nanoparticles varied from 3.6 to 5 nm, depending on the initial concentration of cadmium acetate during the nanocomposite preparation. Fluorescence measurements of the sago-CdS nanocomposite film showed broad emission in the orange-red part of the spectrum. DSC; and TGA analyses revealed significant effects of CdS nanoparticles on the thermal properties of the starch matrix

Composites comprising CdS nanoparticles and poly(ethylene oxide): optical properties and influence of the nanofiller content on the thermal behaviour of the host matrix

Tri-n-octylphosphine oxide-capped CdS nanoparticles were synthesized with the cadmium(II) complex of thiocarbohydrazide as a precursor. Nanocomposites were prepared by mixing a toluene solution of poly(ethylene oxide) (PEO) and the obtained CdS nanoparticles. The ultraviolet-visible spectroscopy measurements showed a blue shift of the onset of optical absorption, compared to bulk CdS, which confirmed the presence of nanostructured CdS. A transmission electron microscopy micrograph of the nanocomposite depicted that the nanoparticles are well dispersed in the PEO matrix. Differential scanning calorimetry analysis revealed hindered crystallization of PEO in the presence of CdS nanoparticles. It was also found that increasing the nanoparticle content led to the shift of the onset of decomposition of the matrix towards higher temperature