Tomorrow's Surgery: Micromotors and Microrobots

Surgical procedures have changed radically over the last few years due to the arrival of new technology. What will technology bring us in the future? This paper examines a few of the forces whose timing are causing new ideas to congeal from the fields of artificial intelligence, robotics, micromachining and smart materials. Intelligence systems for autonomous mobile robots can now enable simple insect level behaviors in small amounts of silicon. These software breakthroughs coupled with new techniques for microfabricating miniature sensors and actuators from both silicon and ferroelectric families of materials offer glimpses of the future where robots will be small, cheap and potentially useful to surgeons. In this paper we relate our recent efforts to fabricate piezoelectric micromotors in an effort to develop actuator technologies where brawn matches to the scale of the brain. We discuss our experiments with thin film ferroelectric motors 2mm in diameter and larger 8mm versions machined from bulk ceramic and sketch possible applications in the surgical field.MIT Artificial Intelligence Laborator

Report on swimbladder disorder in the honeycomb grouper, Epinephelus merra

Swimbladder or airbladder is a thin layered epithelial sac filled with air, lying above the alimentary canal of bony fishes that regulates buoyancy of the fish so that the specific gravity of the fish always matches the depth at which it is swimming. Swimbladder disorder (SBD) is a condition caused by sudden temperature changes impacted stomach resulting from improper feeding or due to bacterial or viral infections of the bladder characterised by inability of the fish to keep a normal upright position in water. Normally gold fishes suffer from SBD due to their globoid body shape. Fish with SBD may float on their side or their back, swim in circles or take head-down posture

Antibacterial activity of aqueous extract from selected macroalgae of southwest coast of India

Aqueous extract of seven species of marine macroalgae were screened for their antimicrobial potency against ten pathogenic bacterial strains. Ulva fasciata, Gracilaria corticata, Sargassum wightii and Padina tetrastromatica showed significantly higher activity against 70% of the tested bacterial isolates. The maximum zone of inhibition was noted for the red alga G.corticata against Proteus mirabilis (17mm) and brown alga P. tetrastromatica against the pathogens Staphylococcus aureus and Vibrio harveyi (15mm). The general trend of inhibitory activity was higher towards Gram negative bacteria

Polymicrobial skin lesions in the red spot emperor, Lethrinus lentjan (Lacepede 1802) during mass incursion towards shore along Kanyakumari coast, south India

Mass incursion of fishes with polymicrobial skin lesions, fin erosions and scale loss was recorded in the red spot emperor Lethrinus lentjan (Lacepede 1802) along the Kanyakumari coast, south India during August 2009. An estimated 2.5 t of fish, mostly the red spot emperors were found to migrate in live condition to the shore areas in a stressful state. Microbiological analyses of tissue from sampled fishes revealed three distinct types of bacterial colonies forming 5.2 x 105 CFU g-1 of the infected tissues. The predominant bacterial colonies were characterized as Aeromonas sp. (70.0%) followed by Flavobacterium sp. (20%) and Vibrio sp. (10%). The Aeromonas isolate was highly susceptible to norfloxacin while the Flavobacterium and Vibrio isolates were susceptible to chloramphenicol. The Aeromonas and Vibrio isolates exhibited protease and amylase enzyme activities in vitro, suggesting their possible role in the progression of skin lesions and scale loss. The possibilities of ambient unknown stressors weakening the fish and subsequent infections by these bacterial isolates are discussed

Subcyclic Switching and Symmetrical Chopper with Tap Changing

Dual-Tap Chopping Stabilizer is an AC voltage regulator with dual tap changer. AC regulators based on tap changers are implemented with SCR’s and TRIACs are widely used for their robustness. With thyristor soft switching, commutation losses are reduced to nearly zero, but it allows only supercyclic commutation, i.e, only one commutation per cycle is possible. By replacing thyristors with high power transistors and gate turn off thyristors, it is possible to achieve several tap changes in one half cycle ,i.e, subcyclic commutation. In this paper an AC chopper is designed with MOSFET switches to achieve subcyclic commutation. Thus subcyclic switching is achieved. A freewheeling circuit is added in the load side. The freewheeling circuit has the following advantages

CLOUD SECURITY AND COMPLIANCE - A SEMANTIC APPROACH IN END TO END SECURITY

The Cloud services are becoming an essential part of many organizations. Cloud providers have to adhere to security and privacy policies to ensure their users' data remains confidential and secure. Though there are some ongoing efforts on developing cloud security standards, most cloud providers are implementing a mish-mash of security and privacy controls. This has led to confusion among cloud consumers as to what security measures they should expect from the cloud services, and whether these measures would comply with their security and compliance requirements. We have conducted a comprehensive study to review the potential threats faced by cloud consumers and have determined the compliance models and security controls that should be in place to manage the risk. Based on this study, we have developed an ontology describing the cloud security controls, threats and compliances. We have also developed an application that classifies the security threats faced by cloud users and automatically determines the high level security and compliance policy controls that have to be activated for each threat. The application also displays existing cloud providers that support these security policies. Cloud consumers can use our system to formulate their security policies and find compliant providers even if they are not familiar with the underlying technology

Organically templated three-dimensional open-framework metal selenites with a diamondoid network

Three-dimensional open-framework metal selenites of the formula, [H2N(CH2)4NH2]0.5[M(HSeO3)(Se2O5)] (M=Zn, Co or Ni), containing both selenite and diselenite units and intersecting 10-membered channels, have been prepared hydrothermally in the presence of piperazine. The compounds are isomorphous and crystallize in the P-1 space group. The structure is built up of MO6 dimers along with Se2O5 and HSeO3 units, the first two forming sheets, which are connected by the selenite units to yield a three-dimensional non-interpenetrating diamondoid network. The 10-membered channels have an unusual structure, being formed by 4-membered (M2Se2) and 6-membered (M2Se4) rings

The effect of interpersonal conflict on employee behaviors: the role of perception of politics and competence uncertainty

Purpose Conflict, between individuals and groups, in organizations is a common phenomenon and can have varied implication for the employee and the organization. This paper aims to determine whether experiencing interpersonal conflict drives employees to engage in prosocial behavior (prohibitive voice) and antisocial behavior (interpersonal deviance). Using Stressor–Emotion Model, Uncertainty Management Theory and Impression Management Motives, this study examines the relationship and explores competence uncertainty as a mediator and perception of politics as a moderator. Design/methodology/approach This study uses a cross-sectional design where data collected is from 386 employees working in nine different public sector enterprises in India. Structural equation modeling using SPSS AMOS was used to analyze the hypothesized relationships. Findings The results show that interpersonal conflict leads to both prohibitive voice behavior and interpersonal deviance. However, the mediating role of competence uncertainty is valid only for the effect of conflict on interpersonal deviance. Also, the perception of politics strengthens the positive relationship between interpersonal conflict and competence uncertainty. Originality/value To the best of the authors’ knowledge, this is one of the first empirical studies to have validated prosocial and antisocial work behavior as outcomes of interpersonal conflict. Again, this is one of the first few studies to examine the mechanism through which interpersonal conflict impacts interpersonal deviance

Electric Field Analysis of Breast Tumor Cells

An attractive alternative treatment for malignant tumors that are refractive to conventional therapies, such as surgery, radiation, and chemotherapy, is electrical-pulse-mediated drug delivery. Electric field distribution of tissue/tumor is important for effective treatment of tissues. This paper deals with the electric field distribution study of a tissue model using MAXWELL 3D Simulator. Our results indicate that tumor tissue had lower electric field strength compared to normal cells, which makes them susceptible to electrical-pulse-mediated drug delivery. This difference could be due to the altered properties of tumor cells compared to normal cells, and our results corroborate this