Parameterized Affect of Transmission-Range on Lost of Network Connectivity (LNC) of Wireless Sensor Networks

Wireless Sensor Networks, referred to as WSNs, are made up of various types of sensor nodes. Recent developments in micro electro-mechanical technology have given rise to new integrated circuitry, microprocessor hardware and nanotechnology, wireless technology, and advanced networking routing protocols. Hospitals and health service facilities, the armed forces, and even residential customers represent a potential huge market for these devices. The problem is that existing sensor network nodes are incapable of providing the support needed to maximize usage of wireless technology. For this reason, there are many novel routing protocols for the wireless sensor networks proposed recently. One is Hierarchical or cluster-based routing. In this paper, we analyze three different types of hierarchical routing protocols: Low Energy Adaptive Clustering Hierarchy (LEACH), Power-Efficient Gathering in Sensor Information Systems (PEGASIS), and Virtual Grid Architecture (VGA). We tried to analyze the performance of these protocols, including the power consumption and overall network performance. We also compared the routing protocol together. This comparison reveals the important features that need to be taken into consideration while designing and evaluating new routing protocols for sensor networks. The simulation results, using same limited sensing range value, show that PEGASIS outperforms all other protocols while LEACH has better performance than VGA. Furthermore, the paper investigates the power consumption for all protocols. On the average, VGA has the worst power consumption when the sensing range is limited, while VGA is the best when the sensing range is increased. Using homogeneous nodes can greatly prolong sensor network’s life time. Also, the network lifetime increases as the number of clusters decreases

Acral necrosis by Stenotrophomonas maltophilia

Keywords:necrosis;skin and soft tissue infection;Stenotrophomonas maltophilia Abstract Background Stenotrophomonas maltophilia (SM) has been considered a nosocomial pathogen. Nevertheless, community acquired infection may occur more frequently than usually recognized. Case We describe distal necrosis of the fingers by SM in a farmer, contracted in the community and successfully treated with a combination of cotrimoxazole and ciprofloxacin. The patient was diagnosed with chronic lymphocytic leukaemia 6 months later. Conclusions This unusual presentation shows that infection with SM should be included in the differential diagnosis of the skin and soft tissue infection, even in apparently healthy patients

The economic impact of Staphylococcus aureus infection in New York City hospitals.

We modeled estimates of the incidence, deaths, and direct medical costs of Staphylococcus aureus infections in hospitalized patients in the New York City metropolitan area in 1995 by using hospital discharge data collected by the New York State Department of Health and standard sources for the costs of health care. We also examined the relative impact of methicillin-resistant versus -sensitive strains of S. aureus and of community-acquired versus nosocomial infections. S. aureus-associated hospitalizations resulted in approximately twice the length of stay, deaths, and medical costs of typical hospitalizations; methicillin-resistant and -sensitive infections had similar direct medical costs, but resistant infections caused more deaths (21% versus 8%). Community-acquired and nosocomial infections had similar death rates, but community-acquired infections appeared to have increased direct medical costs per patient ($35,300 versus$28,800). The results of our study indicate that reducing the incidence of methicillin-resistant and -sensitive nosocomial infections would reduce the societal costs of S. aureus infection

Biomaterial modification of urinary catheters with antimicrobials to give long-term broadspectrum antibiofilm activity

Catheter-associated urinary tract infection (CAUTI) is the commonest hospital-acquired infection, accounting for over 100,000 hospital admissions within the USA annually. Biomaterials and processes intended to reduce the risk of bacterial colonization of the catheters for long-term users have not been successful, mainly because of the need for long duration of activity in flow conditions. Here we report the results of impregnation of urinary catheters with a combination of rifampicin, sparfloxacin and triclosan. In flow experiments, the antimicrobial catheters were able to prevent colonization by common uropathogens Proteus mirabilis, Staphylococcus aureus and Escherichia coli for 7 to 12 weeks in vitro compared with 1–3 days for other, commercially available antimicrobial catheters currently used clinically. Resistance development was minimized by careful choice of antimicrobial combinations. Drug release profiles and distribution in the polymer, and surface analysis were also carried out and the process had no deleterious effect on the mechanical performance of the catheter or its balloon. The antimicrobial catheter therefore offers for the first time a means of reducing infection and its complications in long-term urinary catheter users