Vidya Singh

Antimicrobial and Herbal Drug Resistance in Enteric Bacteria Isolated from Faecal Droppings of Common House Lizard/Gecko (Hemidactylus frenatus)

From 194 faecal dropping samples of common house geckos collected from offices (60), houses (88), integrated farm units (IFS,18) and hostels, guest houses, and dining rooms of different canteen/mess (HGM, 28), 326 bacterial isolates of enteric bacteria belonging to 17 genera and 34 species were detected. Escherichia coli were the most frequently (39) isolated followed by Citrobacter freundii (33), Klebsiella pneumonia (27), Salmonella indica (12), Enterobacter gergoviae (12), and Ent. agglomerans (11). Other important bacteria isolated from gecko droppings were Listonella damsela (2), Raoultella terrigena (3), S. salamae (2), S. houtenae (3), Edwardsiella tarda (4), Edwardsiella hoshinae (1), and Klebsiella oxytoca (2). Of the 223 isolates tested for antimicrobial drug sensitivity, 27 (12.1%) had multiple drug resistance (MDR). None of the salmonellae or edwardsiellae had MDR however, MDR strains were significantly more common among Escherichia spp. (P = 1.9 × 10−5) and isolates from IFS units (P = 3.58 × 10−23). The most effective herbal drug, Ageratum conyzoides extract, inhibited growth of only 27.8% of strains tested followed by ethanolic extract of Zanthoxylum rhetsa (13.9%), eucalyptus oil (5.4%), patchouli oil (5.4%), lemongrass oil (3.6%), and sandalwood oil (3.1%), and Artemisia vulgaris essential oil (3.1%).

Springback Analysis of Rectangular Sectioned Bar of Non Linear Work-Hardening Materials under Torsional Loading

This paper deals with the springback problems of rectangular section bars of non-linear work-hardening materials under the torsional loading. Using the deformation theory of plasticity, a numerical scheme based on the finite difference approximation has been proposed. The growth of the elastic-plastic boundary and the resulting stresses while loading, and the springback and the residual stresses after unloading are calculated. The results are verified experimentally with mild steel bars having a rectangular cross-section and the experimental results have been found to agree well with the theoretical results obtained numerically.

Aerobic Mesophilic Bacterial Flora of Vagina of Healthy Mithun (Bos frontalis)

Aerobic Mesophilic Bacterial Flora of Vagina of Healthy Mithun (Bos frontalis) In the study on 60 vaginal swabs of apparently healthy mithuns, aerobically growing mesophilic bacteria could be detected in 55 swabs. Probability of isolation of more than one type of bacteria was significantly higher (70%) than isolation of one type (21.7%) or no (8.3%) bacteria from mithun vaginal swabs. The 136 bacteria (29 Gram positive, GPBs and 107 Gram negative, GNBs) isolated could be identified belonging to 24 species of 13 genera. The commonly isolated bacteria were Escherichia coli (43.3%), Enterococcus casseliflavus (38.3%), Proteus penneri (25%), Pseudomonas aeruginosa (15%), Klebsiella pneumoniae (18.3%) and Aeromonas eucranophila (11.7%). All GPBs were sensitive to ciprofloxacin, tetracycline, norfloxacin, nalidixic acid, nitrofurantoin and netillin and all GNBs were sensitive to gentamicin. All K. pneumoniae and majority of the E. coli and Aeromonas isolates were resistant to ampicillin.

Occurrence of Bordetella Infection in Pigs in Northern India

Bordetella bronchiseptica infection causing atrophic rhinitis in pigs is reported from almost all countries. In the present study, occurrence of Bordetella infection in apparently healthy pigs was determined in 392 pigs sampled to collect 358 serum samples and 316 nasal swabs from Northern India by conventional bacterioscopy, detection of antigen with multiplex polymerase chain reaction (mPCR), and detection of antibodies with microagglutination test (MAT) and enzyme linked immune-sorbent assay (ELISA). Bordetella bronchiseptica could be isolated from six (1.92%) nasal swabs. Although isolates varied significantly in their antimicrobial sensitivity, they had similar plasmid profile. The genus specific and species specific amplicons were detected from 8.2% and 4.4% nasal swabs using mPCR with alc gene (genus specific) and fla gene and fim2 gene (species specific) primers, respectively. Observations revealed that there may be other bordetellae infecting pigs because about 50% of the samples positive using mPCR for genus specific amplicons failed to confirm presence of B. bronchiseptica. Of the pig sera tested with MAT and ELISA for Bordetella antibodies, 67.6% and 86.3% samples, respectively, were positive. For antigen detection mPCR was more sensitive than conventional bacterioscopy while for detection of antibodies neither of the two tests (MAT and ELISA) had specificity in relation to antigen detection. Study indicated high prevalence of infection in swine herds in Northern India.

Performance Analysis of ZigBee Protocol in Smart Dust Communication Network

Smart Dust is the network of small devices (also called as Sensor Nodes) with many electronic components such as memory, CPU, radio and sensor and each of these components consumes power. Sensor nodes have a battery and can work only as long as the battery lasts. In other words, it is very important to optimize every computation in order to increase the sensor’s lifetime. To achieve this, an energy efficient protocol called as ZigBee protocol is analyzed. Analysis is done using two different topologies (Random and Clustered Topology). Both topologies are properly analyzed in terms of number of nodes and in terms of number of nodes/cluster respectively. Parameters used for analysis are Total Packets Transmitted, Total Packet Loss, Packet Loss Rate and Bit Rate.