Security in Wireless Sensor Networks: Issues and Challenges

Wireless Sensor Network (WSN) is an emerging technology that shows great promise for various futuristic applications both for mass public and military. The sensing technology combined with processing power and wireless communication makes it lucrative for being exploited in abundance in future. The inclusion of wireless communication technology also incurs various types of security threats. The intent of this paper is to investigate the security related issues and challenges in wireless sensor networks. We identify the security threats, review proposed security mechanisms for wireless sensor networks. We also discuss the holistic view of security for ensuring layered and robust security in wireless sensor networks.Comment: 6 page

The live cell DNA stain SiR-Hoechst induces DNA damage responses and impairs cell cycle progression

AbstractSiR-Hoechst (SiR-DNA) is a far-red fluorescent DNA probe being used widely for time-lapse imaging of living cells that is reported to be minimally toxic at concentrations as high as 10–25 µM. However, measuring nuclear import of Cyclin B1, inhibition of mitotic entry, and the induction of γH2AX foci in cultured human cells reveals that SiR-Hoechst induces DNA damage responses and G2 arrest at concentrations well below 1 µM. SiR-Hoechst is useful for live cell imaging, but it should be used with caution and at the lowest practicable concentration.</jats:p

Focused RF ablation using magnetic fluids

Cataloged from PDF version of article.In most developed countries, cancer is presently responsible for about 25% of all deaths. Heat therapies like hyperthermia and thermoablation are very promising approaches in the treatment of the cancer. Since these are physical treatment methods they have fewer side affects compared to chemo- and radio-therapy. Currently, various types of heat treatment modalities are available like microwave, ultrasound, RF capacitance hyperthermia, RF probe hyperthermia, magnetic fluid hyperthermia, but non of these methods have the ability to accurately deliver high heat energy to deeply seated tumors without damaging the healthy surrounding tissues. In this thesis, a novel RF ablation system was developed capable of focusing the heat in to very small areas in the order of millimeters, which will allow heating of the tumors without destroying collateral normal tissues. Generally, in this system the tumor ablation is achieved via coupling RF energy on the magnetic fluids which are previously dispersed in to the tumor tissue. By considering the human safety limits (nerve stimulation and tissue eddy current heating safeties) optimum treatment parameters like particle size of the magnetic fluids, frequency and strength of the applied RF field are obtained. The utilization of the optimum parameters may lead to the very effective operation of the ablation system where treatments can be done with very small amounts of fluid injections, in short durations. We believe that by the studies conducted in this thesis, magnetic fluid hyperthermia (tumor ablations using magnetic fluids) can be a much more effective method so that it can be used as the one of the most important tumor treatment techniques in future.Taşçı, T. OnurM.S

Odnos između težine azotemije i plinova u krvi u 101 teleta s neonatalnom dijarejom

The aim of this study was to determine the relationship between the severity of azotemia and blood gas parameters in 101 neonatal calves with diarrhea. The calves were divided into 3 groups on the basis of their creatinine levels. The 3 groups were defined as: the non-azotemia group (5.01 mg/dL). Azotemia was not detected in 35 of the 101 calves with diarrhea, mild-moderate azotemia was identified in 34, and severe azotemia in 32. Blood pH was significantly lower in the severe azotemia group compared to the non-azotemia and mild-moderate azotemia groups, while K and lactate levels were significantly higher. Although the HCO3 - and BE values of the severe azotemia group were lower than the other groups, a statistical difference was only found with the mild-moderate azotemia group. Ionized calcium (iCa+2) level was also lower in the severe azotemia group compared to the other groups, but the difference was only significant with the non-azotemia group. In conclusion, it was observed that azotemia is a common occurrence in neonatal calves with diarrhea, and there is a significant relationship between the severity of azotemia and blood gases. Therefore, it may be concluded that it would be beneficial to monitor renal functions during the treatment of calves with neonatal diarrhea.Cilj je ovog istraživanja bio procijeniti odnos između težine azotemije i pokazatelja plinova u krvi u 101 teleta s dijarejom. Telad je na temelju razine kreatinina podijeljena u tri skupine: skupina bez azotemije (5,01 mg/dL). Azotemija nije otkrivena u 35 od 101 teleta s dijarejom, blaga – umjerena azotemija pronađena je u 34 teleta, a teška azotemija u 32 teleta. Vrijednost pH krvi bila je znakovito niža , a razina kalija i laktata znakovito viša, u skupini s teškom azotemijom u usporedbi s ostalim dvjema skupinama. Iako su vrijednosti HCO3 - i BE u skupini teladi s teškom azotemijom bile niže nego u drugim skupinama, statistički znakovita je razlika pronađena samo u odnosu na skupinu s blago-umjerenom azotemijom. Razina ioniziranog kalcija (iCa+2) također je bila niža u skupini s teškom azotemijom u usporedbi s drugim skupinama, ali je razlika bila znakovita samo u odnosu na skupinu bez azotemije. Rezultati istraživanja pokazuju da se azotemija često pojavljuje u neonatalne teladi s dijarejom i da postoji znakovita povezanost između težine azotemije i plinova u krvi. Može se stoga zaključiti da bi praćenje bubrežne funkcije bilo korisno u liječenju teladi s neonatalnom dijarejom