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The emerging field of micro dimensioned biomedical sensors involves tremendous research to detect biomolecules and pathogens with an improved sensitivity and a low limit of detection. The use of magnetic labels in biosensors has increased so much over the past years due to unique advantages of magnetic sensing techniques. Planar microcoil based magnetic biosensors help to reduce the system size and improve the sensitivity. This paper proposes non-spiral planar microcoil based magnetic sensors which are advantageous over conventional spiral coil based sensors regarding fabrication easiness and heating losses. The method of microfabrication of the coil sensor described in this paper makes use of a single mask process which is the simplest among all existing processes. Non-spiral planar microcoil sensors based on induction-balance and differential sensing principles are studied in this work. Also, an analytical model is developed to design the dimensions of the sensing coil. Comprehensive finite element analysis of the sensors is performed, and the results are compared with the experimental outcomes. A comparative study of the proposed sensors with the existing planar coil magnetic sensors is also presented to show the advantages of the proposed coil sensors over the existing ones.

The gene for receptor tyrosine kinase ErbB2 is amplified in breast and ovarian tumours. The linear pathway by which signals are transduced through ErbB2 are well known. However, second generation questions that address spatial aspects of signaling remain. To address this, we have undertaken a mass spectrometry approach to identify phosphoproteins specific for ErbB2 using the inhibitors Lapatinib and CP724714 in ovarian cancer cells. The ErbB2 specific proteins identified in SKOV-3 cells were Myristoylated alanine-rich C-kinase substrate, Protein capicua homolog, Protein peptidyl isomerase G, Protein PRRC2C, Chromobox homolog1 and PRP4 homolog. We have evaluated three phosphoproteins PKM2, Aldose reductase and MARCKS in SKOV-3 cells. We observed that PKM2 was phosphorylated by EGF but was not inhibited by Lapatinib and CP724714. The activity of aldose reductase in reducing NADPH as a substrate was significantly higher in EGF stimulated cells which was inhibited by Lapatinib and CP724714 but not by Geftinib (EGFR inhibitor). MARCKS was phosphorylated on stimulation of SKOV-3 cells with EGF that was inhibited by Lapatinib and CP724714 which was dependent on the kinase activity of ErbB2. These results have identified phosphoproteins that are specific to ErbB2 which have not been previously reported and sets the basis for future experiments.

Magnetic microbeads have acquired broad scope in immunoassay applications to detect pathogens causing dreadful diseases. In this work, we propose magnetic sensors using non-spiral planar microcoils to sense the presence of the microbeads with better sensitivity and fabrication simplicity. Experiments are performed by measuring the current induced in the sensing coil in the presence of iron oxide microbeads. Meanwhile, simulation studies of the sensors are conducted to verify the experimental results. A comparison of the proposed and the reported works on planar coil sensors are also presented. Improved limit of detection with reduced power consumption is observed to be the significant advantage of the induction-balance and differential sensors compared to the reported works.

Electromagnetic microactuators offer several advantages for robotic applications such as relatively large stroke and low input voltage requirements. Micro coils are significant components for electromagnetic microactuators for generating force required for micro robots. Non-spiral planar microcoils of square and circular geometries are analyzed here considering the fabrication easiness and low power consumption of non-spiral planar coils. Microfabrication of non-spiral planar coil is simpler and requires a single mask process only. Comparison between non-spiral coils and conventional spiral coils are also discussed. Series resistance of non-spiral coil is found out to be lesser than that of spiral coils though magnetic field is slightly lesser for non-spiral coils. The fabrication advantages and low power dissipation of non-spiral structures make them a strong alternative for conventional spiral planar microcoils. Comparison of different planar microcoils shows that the circular non-spiral coil gives better performance than other coil geometries considered here for robotic applications. Circular coil is found to provide a uniform field with lesser parasitic resistance. Electromagnetic microactuator using non-spiral planar circular and square microcoils are also analyzed to compare the performance between the two coil types. The results show that the force generated using non-spiral circular microcoil in the microactuator is adequate for microrobotic applications with an added advantage of uniform magnetic field provided by the circular coils.

The objective of this research work is to isolate and identify calcite precipitating bacteria and to check the suitability of these bacteria for use in concrete to improve its strength. Bacteria to be incorporated in concrete should be alkali resistant to endure the high pH of concrete and endospore forming to withstand the mechanical stresses induced in concrete during mixing. They must exhibit high urease activity to precipitate calcium carbonate in the form of calcite. Bacterial strains were isolated from alkaline soil samples of a cement factory and were tested for urease activity, potential to form endospores and precipitation of calcium carbonate. Based on these results, three isolates were selected and identified by 16S rRNA gene sequencing. They were identified as Bacillus megaterium BSKAU, Bacillus licheniformis BSKNAU and Bacillus flexus BSKNAU. The results were compared with B. megaterium MTCC 1684 obtained from Microbial Type Culture Collection and Gene Bank, Chandigarh, India. Experimental work was carried out to assess the influence of bacteria on the compressive strength and tests revealed that bacterial concrete specimens showed enhancement in compressive strength. The efficiency of bacteria toward crack healing was also tested. Substantial increase in strength and complete healing of cracks was observed in concrete specimens cast with B. megaterium BSKAU, B. licheniformis BSKNAU and B. megaterium MTCC 1684. This indicates the suitability of these bacterial strains for use in concrete. The enhancement of strength and healing of cracks can be attributed to the filling of cracks in concrete by calcite which was visualized by scanning electron microscope.

Objective Acute suppurative neck infections associated with third or fourth branchial arch fistulas are frequently recurrent. Third and fourth branchial arch anomalies are much less common than those of second arch and usually present with left thyroid lobe inflammation. The authors present their experience with 15 cases of pyriform sinus fistulae (PSF) of third branchial arch origin and 3 cases of fourth arch origin, all of which presented as recurrent neck infection mainly on the left side. Methods A retrospective review of 18 cases of third and fourth arch fistulae treated at JIPMER from 2005 to 2010. This study includes 18 patients with PSF diagnosed by the existence of fistulous tract radiologically and intraoperatively with pathological correlation. Neck exploration with excision of tract and left hemithyroidectomy was performed in all cases. Results The patients consisted of 7 males and 11 females, and the ages ranged from 3 to 15 years. All of them presented with recurrent episodes of neck infection. Investigations performed include computed tomography (CT) fistulography, barium swallow and ultrasound which were useful in delineating pyriform sinus fistulous tract preoperatively. All cases were on the left side and the fistula was identified by barium swallow in 14 cases (80%), while intraoperative and pathologic confirmation of the tract was possible in all cases (100%). Neck exploration with an emphasis on complete exposure of the recurrent laryngeal nerve and exposure of the pyriform sinus opening to facilitate complete fistulous tract excision with left hemithyroidectomy was successful in all patients. A follow up period of 1–3 years showed no recurrence. Conclusion Recurrent neck infection in a child should alert the physician to the possibility of an underlying pyriform sinus fistula of branchial origin and CT fistulography should be performed after the resolution of the neck infection to delineate the tract anatomically.