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1.
Sudden cardiac death (SCD) is reported as leading cause of death in patients on chronic hemodialysis. Arrhythmias are proposed to be a major predisposing factor for SCD. However, triggers for potentially lethal arrhythmias are not well understood. Here we describe a case of 72‐year‐old man on chronic hemodialysis via permanent Central venous catheter (CVC) who was admitted for evaluation after unwitnessed fall. Within 10 minutes of his first routine dialysis session in the hospital, he had cardiac‐arrest. He was successfully resuscitated within 3 minutes. The next day, fifteen minutes into the dialysis session, he had bradycardia with telemetry demonstrating long sinus pause and he lost consciousness. After few minutes of Advanced Cardiac Life Support (ACLS) he regained pulse and consciousness. Further review of the chest X‐ray revealed the tip of CVC to be directly touching the distal Superior Vena Cava (SVC) wall. We felt the catheter tip may have migrated after the fall and now is irritating the Sinoatrial node and triggering bradyarrhythmia. Next day, the CVC was exchanged, and the tip was placed higher up in superior vena‐cava. After repositioning, we started him on dialysis under intensive monitoring, and he tolerated well without any arrhythmia. Subsequent dialysis was uneventful. We describe a case of recurrent symptomatic intra‐dialytic bradycardia due to abnormal positioning of CVC that resolved after the repositioning of the catheter. This case in addition to similar case in nondialysis settlings provides additional insights into mechanisms of fatal arrhythmias in hemodialysis patient having CVC.  相似文献   
2.
Wireless Personal Communications - The lightweight cryptography (LWC) is an interesting research area in the field of information security. So, different lightweight mechanisms have been developed...  相似文献   
3.
The results of an experimental study on the destruction of disperse dyes by chemical oxidation using ozone, hypochlorite and Fenton reagent (H2O2 + Fe2+) are compared with the data obtained by electrochemical oxidation. While the results obtained during hypochlorite oxidation were not satisfactory (only 35% reduction of colour was achieved at a dose of 6 g dm(-3)), ozonation enabled colour to be reduced by up to 90% (ozone dose 0.5 g dm(-3)). A high decolourisation degree was however accompanied by a low removal (10% efficiency) of chemical oxygen demand (COD). Trials of electrochemical oxidation proved this process much more efficient. Under the conditions of an acidic pH in 40 min of electrolysis a 79% elimination of COD was achieved at the Ti/Pt-Ir anode, which proved the best of seven different tested materials. Simultaneously 90% colour was removed. Indirect oxidation, by means of chlorine-deriving compounds, was the predominating process leading to the pollutants depletion. The best treatment results were obtained with the Fenton process, which under the optimal pH equal to 3 and hydrogen peroxide and ferrous sulphide dose of 600 and 550 mg dm(-3), respectively, resulted in a final effluent being colourless and with the residual COD equal to 100 mg dm(-3).  相似文献   
4.
Nandy T  Kaul SN 《Water research》2001,35(2):351-362
The concept of immobilization technology has been incorporated in this research study for biomethanation of high strength herbal based pharmaceutical wastewater. Accordingly, an investigation has been made on laboratory scale to assess the feasibility of an anaerobic fixed film fixed bed reactor system to pre-treat herbal-based pharmaceutical wastewater with recourse to energy recovery, including influence of operating conditions. The work was carried out with laboratory-scale upflow reactor, equipped with nylon scrubber as random support. The reactor was operated at 35 degrees C. COD removal efficiencies ranging from 76 to 98% were achieved for organic loading rates upto 10 kgCOD/m3 d, while the highest organic loading rate (around 48 kg COD/m3 d) led to efficiencies of 46-50%. The influences of hydraulic retention time and substrate concentration were also studied. The reactors did now show destabilization under impulse hydraulic and organic overloadings. Reactor stability was easily achieved under intermittent operation, with breaks, after which the reactors rapidly returned to their optimal performance.  相似文献   
5.
Feasibility of a waste material, flyash, as a material for purification of wastewater containing Lissamine Red has been studied. Effects of time and concentration, temperature and pH on the removal of the dye have been studied. Lower concentrations favour the uptake of dye from water and the maximum removal was observed at a dye concentration of 20 mgL m 1 , 30°C, pH of 7 and adsorbent particle size of 53 µm. Dynamics of the uptake was studied using Lagergren's equation. The mass transfer coefficient was found to be 0.05 cmmin m 1 at a concentration of 20 mgL m 1 , 30°C and 53 µm particle size.  相似文献   
6.
Fenbufen, a member of nonsteroidal antiinflammatory drugs and widely used in the treatment of rheumatoid arthritis was imprinted by utilizing a zwitterionic polymeric format, N-[(phenylenediammonium) maleimidopropane sulfonate] copolymer. Imprinting was carried out by grafting polymer on a photoiniferter modified silica gel via living radical polymerization. Electrostatic interactions along with complementary H-bonding and other hydrophobic interactions inducing additional synergetic effect between the template (fenbufen) and the imprinted surface led to the formation of imprinted sites. Grafted molecularly imprinted polymer (MIP) was characterized by FTIR and surface area measurements besides the recognition, rebinding and selectivity studies. The surface area, pore diameter and pore volume of the MIP are 259.06 m2/g, 4.99 nm and 0.32 cm3/g, respectively. The MIP was able to selectively and specifically take up fenbufen quantitatively. Hence, a facile, specific and selective technique using surface-grafted specific molecular contours developed for specific and selective uptake of fenbufen in the presence of various interferrants, in different kinds of matrices is presented.  相似文献   
7.
Grundwasser - Eine erfolgreiche biologische In-situ-Sanierung von PCE-kontaminierten Grundwasserleitern erfordert hinreichend reduzierende Bedingungen sowie die Anwesenheit von molekularem...  相似文献   
8.
Behavior of cold-rolled fcc Ni88.4Cr9.2W2.4 alloy during heating has been studied. Two consecutive exothermic processes were detected using differential scanning calorimetry, high-temperature X-ray diffraction, and dilatometry. The processes were identified as polygonization and recrystallization, which lead to cube texture formation, as was shown by X-ray diffraction and electron backscatter diffraction. The heat effects of these processes were determined.  相似文献   
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