Gaseous fluxes in the nitrogen and carbon budgets of subsurface flow constructed wetlands

In 2001 and 2002, fluxes of N(2)O, CH(4), CO(2) and N(2) were measured in two constructed wetlands (CW) for domestic wastewater treatment in Estonia. The difference between the median values of N(2)O, CH(4), and N(2) fluxes in the horizontal subsurface flow (HSSF) CWs was non-significant, being 1.3-1.4 and 1.4-4.1 mg m(-2) d(-1) for N(2)O-N and CH(4)-C, and 0.16-0.17 g N m(-2) d(-1) for N(2)-N respectively. The CO(2)-C flux was significantly lower (0.6 g C m(-2) d(-1)) in one of the HSSF filters of a hybrid CW, whereas the single HSSF and VSSF filters emitted 1.7 and 2.0 g C m(-2) d(-1). The median value of CH(4)-C emission in CWs varied from 1.4 to 42.6 g C m(-2) d(-1), being significantly higher in the VSSF filter beds. We also estimated C and N budgets in one of the HSSF CWs (312.5 m(2)) for 2001 and 2002. The total C input into this system was similar in 2001 and 2002, 772 and 719 kg C year(-1), but was differently distributed between constituent fluxes. In 2001, the main input flux was soil and microbial accumulation (663 kg C year(-1) or 85.8% of total C input), followed by plant net primary production (NPP) (10.2%) and wastewater inflow (3.9%). In 2002, 55.7% of annual C input was bound in plant NPP, whereas the increase in soil C formed 28.5% and wastewater inflow 15.7%. The main C output flux was soil respiration, including microbial respiration from soil and litter, and the respiration of roots and rhizomes. It formed 120 (97.5%) and 230 kg C year(-1) (98.2%) in 2001 and 2002 respectively. The measured CH(4)-C flux remained below 0.1% of total C output. The HSSF CW was generally found to be a strong C sink, and its annual C sequestration was 649 and 484 kg C year(-1) per wetland in 2001 and 2002 respectively. However, negative soil and microbial accumulation values in recent years indicate decreasing C sequestration. The average annual N removal from the system was 38-59 kg N year(-1) (46-48% of the initial total N loading). The most important flux of the N budget was N(2)-N emission (22.7 kg in 2001 and 15.2 kg in 2002), followed by plant belowground assimilation (2.3 and 11.9 kg N year(-1) in 2001 and 2002), and above-ground assimilation (1.9 and 9.2 kg N year(-1), respectively). N(2)O emission was low: 0.37-0.60 kg N year(-1)(.).     

Fouling Detection in an Optically Accessible Microstructured Heat Exchanger

The application of highly effective microstructured devices in continuous production and industrial environments is frequently prone to fouling. A new method is presented to characterize fouling in these microstructures. Thermal fouling of aqueous solutions containing whey protein were used as a test system. Different fouling effects could be observed and distinguished. Integral fouling indicators, such as thermal fouling resistance and pressure drop, as conventional criteria for the occurrence of fouling were compared with direct local optical observation. Low thermal fouling resistances could be detected.     

锁存继电器的CMOS电路

控制应用经常要求将一只继电器锁存定位,直到需要改变其状态时为止。完成这个任务的是锁存继电器。当给它们发送一个脉冲时,它们可能保持在当前状态,也可能改变状态,具体取决于脉冲的极性以及继电器当前状态。图1中电路会根据一     

Pulsed flow for enhanced cleaning in food processing

The use of slow (～1 Hz) flow oscillation imposed on a stationary flow of liquid has been shown to enhance shear stresses imposed on a surface and to mitigate fouling or enhance cleaning. Examples of the application of pulsed flow are presented in this paper. A new measuring technique in combination with tailored CFD simulations was developed for monitoring the cleaning of complex piping equipment with pulsed flow. A time-independent and isotropic approach to model the wall shear stress is introduced. The optical monitoring procedure uses a model food soil consisting of starch as matrix material and phosphorescent zinc sulfide crystals as optical tracer. Investigations of pulsed flow cleaning published prior to this work focused on tests with straight pipes, whereas difficulties in industrial cleaning operations more often arise while operating piping systems and plant components with complex geometries. Therefore cleaning experiments were performed in a CIP test rig simulating industrial cleaning processes. The results with pulsed flow show an enhancement of cleaning efficiency at locations difficult to access using stationary flow.     

Inhibition of calcium influx during hypoxia/reoxygenation in primary cultured rat hepatocytes

Calcium has been demonstrated to play an important role in hepatocyte damage during ischemia/reperfusion phases. Calcium influx was determined in primary cultured rat hepatocytes submitted to a succession of warm hypoxia and reoxygenation phases in the presence of diltiazem, gallopamil and a Na+/H+ antiport inhibitor, HOE-694. Only diltiazem significantly inhibited calcium influx with higher potency after reoxygenation than after hypoxia only, suggesting a complex mechanism of action of diltiazem which could act on different physiological functions involved in Ca2+ invasion of hepatocytes after hypoxic insult.     

ARG1 (altered response to gravity) encodes a DnaJ-like protein that potentially interacts with the cytoskeleton

Gravitropism allows plant organs to direct their growth at a specific angle from the gravity vector, promoting upward growth for shoots and downward growth for roots. Little is known about the mechanisms underlying gravitropic signal transduction. We found that mutations in the ARG1 locus of Arabidopsis thaliana alter root and hypocotyl gravitropism without affecting phototropism, root growth responses to phytohormones or inhibitors of auxin transport, or starch accumulation. The positional cloning of ARG1 revealed a DnaJ-like protein containing a coiled-coil region homologous to coiled coils found in cytoskeleton-interacting proteins. These data suggest that ARG1 participates in a gravity-signaling process involving the cytoskeleton. A combination of Northern blot studies and analysis of ARG1-GUS fusion-reporter expression in transgenic plants demonstrated that ARG1 is expressed in all organs. Ubiquitous ARG1 expression in Arabidopsis and the identification of an ortholog in Caenorhabditis elegans suggest that ARG1 is involved in other essential processes.     

Malignant hyperthermia and neuroleptic malignant syndrome in a patient during treatment for acute asthma

PURPOSE: The safety and diagnostic efficacy of iodixanol (Visipaque) 270 mg I/ml was compared to that of iopamidol (Iopamiron) 300 mg I/ml in knee arthrography. MATERIAL AND METHODS: This trial was a bi-center double-blind trial including 128 patients (iodixanol/iopamidol 64/64 patients). Efficacy was evaluated by blinded grading of the diagnostic quality of the p.a. images taken 0, 12 and 25 min after contrast administration by the examining radiologist and later at a consensus evaluation by two experienced skeletal radiologists. Adverse events were recorded. RESULTS: No patient experienced any adverse event. The proportion of better images at both 12 and 25 min after injection was higher in the iodixanol group compared to the iopamidol group both by the examining radiologist and at the consensus evaluation. CONCLUSION: In the knee joint iodixanol is a safe contrast medium. The contrast effect of iodixanol lasted longer than that of iopamidol, which can be important when performing arthrography, especially CT arthrography, where the time between puncture and examination can be prolonged.