Flicker responses of different lamp types

Nowadays, more and more lamp types are being used. Since different lamp types have different working principles, they also have different flicker responses. This paper shows the measurement results of different flicker responses for various types of lamps. These results prove that the UIE/IEC flickermeter, which has been used widely around the world for many years, cannot be used to advise on the flicker level of all lamp types. This is because of the fact that this flickermeter is based on a 230 V, 60 W or 120 V, 60 W incandescent lamp and can be used as reference only for this type of lamp or as reference to the standard. The UIE/IEC (International Union for Electricity Applications/International Electrotechnical Committee) flickermeter and the existing standards are therefore insufficient for other lamp types. This paper describes a proposal to improve the UIE/IEC flickermeter.     

Oculocerebrocutaneous syndrome: report of three additional cases and aetiological considerations

Atrial fibrillation (AF) has been recognized, with increasing concern, as a potentially disabling illness, occurring either as a symptom of many cardiac diseases or as an isolated disorder. It can independently contribute to mortality and morbidity and may have serious prognostic importance in acute or chronic cardiac disease. In patients with symptomatic drug refractory atrial fibrillation, ventricular rate control by atrioventricular nodal ablation or modification commonly results in pacemaker implantation. The concept of AF prevention by pacemaker therapy has been introduced in patients with bradycardia-tachycardia syndrome or vagally mediated bradycardia-dependent AF. In patients with sick sinus syndrome, atrial pacing has proved to be more effective than VVI pacing in maintaining the electrical stability of the atrium in long-term follow up. Recently, the development of new techniques of atrial pacing employing pacing at two atrial sites may improve the effectiveness of the AF prevention by pacemaker therapy. Dual-site right atrial pacing using overdrive stimulation activates simultaneously the high right atrium and the left atrium via the ostium of the coronary sinus. Two main mechanisms have been proposed to explain the favourable effect of this technique. One is the suppression of atrial premature beats initiating AF by the overdrive pacing. The second is the alteration of atrial activation pattern by preexcitation of the area of the coronary sinus ostium which permits earlier recovery of excitability in sites of atrial conduction delay. The combination of drug therapy and pacing is essential for effective AF control. We have hitherto studied 30 patients with single- and dual-site pacing. Single-site pacing was performed at the high right atrium or coronary sinus ostium. The dual-site pacing mode increased the arrhythmia-free intervals, decreased patients' arrhythmia-related symptoms and anti-arrhythmic drug use as compared to the period preceding institution of pacing and incrementally over conventional high right atrial pacing alone. A multicentre randomized trial, Dual-site Atrial Pacing for Prevention of Atrial Fibrillation (DAPPAF), evaluating three pacing modes (dual-site, single-site and support pacing), is now in progress.     

Involvement of Virus-Induced Interferon Production in IgG Autoantibody-Mediated Anemia

Infection with viruses, such as the lactate dehydrogenase-elevating virus (LDV), is known to trigger the onset of autoimmune anemia through the enhancement of the phagocytosis of autoantibody-opsonized erythrocytes by activated macrophages. Type I interferon receptor-deficient mice show enhanced anemia, which suggests a protective effect of these cytokines, partly through the control of type II interferon production. The development of anemia requires the expression of Fcγ receptors (FcγR) I, III, and IV. Whereas LDV infection decreases FcγR III expression, it enhances FcγR I and IV expression in wild-type animals. The LDV-associated increase in the expression of FcγR I and IV is largely reduced in type I interferon receptor-deficient mice, through both type II interferon-dependent and -independent mechanisms. Thus, the regulation of the expression of FcγR I and IV, but not III, by interferons may partly explain the exacerbating effect of LDV infection on anemia that results from the enhanced phagocytosis of IgG autoantibody-opsonized erythrocytes.     

Spacer fabric supported flat-sheet membranes: A new era of flat-sheet membrane technology

Current flat sheet MBR membranes are sandwich constructions containing at least 3 different layers. These membranes have no or only very backwash-ability and their envelope construction is a very labour-intensive multi-step operation.In this paper an innovative single method for constructing a prior-to-art back-washable flat sheet membrane envelope is described. The key element of this concept is the use of a 3D spacer-fabric as a membrane support stucture. Spacer-textiles can be made by a knitting or weaving process and they are normally used for the construction of all kind of light-weight composite materials. They basically consist of two faces (their outer layers), which are connected with each other by a multitude of monofilament spacer yarns. As a result a solid three dimentional structure is obtained which contains three distinguishable layers: the two faces (each e.g. 0.5 mm thick), and a hollow space in between them formed by the monofilament spacer yarns. In our concept the hollow space of the spacer fabric is used as the permeate drainage channel, whereas its faces are used for membrane anchoring. The interesting spacer fabrics for use as a membrane support have a thickness in between 2 and 10 mm. In our manufacturing process both faces of the spacer-fabric are directly and simultaneously coated with membrane dope in a vertical set-up. The pore size of both membrane layers is controlled by a combined VIPS and LIPS process. A membrane envelope has been realized with 0.3 μm pores having a pure water permeability of 1500 l/hm² bar. A membrane adhesion test revealed that the membrane layers are attached well to the spacer fabric and can simply be back-washed with a TMP of 1 bar. Application tests showed that the critical flux of the IPC membrane is similar to a commercial MBR membrane type.     

Nuclear DNA content and morphological characteristics in the prognosis of adrenocortical carcinoma

Bathophenanthrolinedisulfonic acid (4,7-diphenyl-1,10-phenanthrolinedisulfonic acid [BPS]) and 3-(2-pyridyl)-5,6-bis(4-phenylsulfonic acid)-1,2,4-triazine (ferrozine), chelators of ferrous iron, are often used to determine iron(II) concentrations in various samples and for identifying or measuring iron reduction in biological systems. In this study, the efficacy of ferrozine and BPS to chelate iron(II) reduced from Fe(3+)-ligands by selected reducing agents was determined. Our results indicate that (i) BPS and ferrozine are not equivalent as kinetic indicators of iron reducing activity; (ii) apparent initial rates of reduction of Fe(3+)-ligands by dithiothreitol, as indicated by formation of complexes of iron(II) with either BPS or ferrozine, differed by a factor of 50; and (iii) nonspecific reduction of some Fe(3+)-ligands by both BPS and ferrozine occurred. Under identical conditions, rates of formation of Fe(2+)-ferrozine generally were slower than rates of formation of Fe(2+)-BPS. These data suggest careful consideration should be given in the design of any experiments where kinetics of iron reduction are monitored with BPS or ferrozine.     

Growing Azolla to produce sustainable protein feed: the effect of differing species and CO2 concentrations on biomass productivity and chemical composition

BACKGROUND

Since available arable land is limited and nitrogen fertilizers pollute the environment, cropping systems ought to be developed that do not rely on them. Here we investigate the rapidly growing, N₂‐fixing Azolla/Nostoc symbiosis for its potential productivity and chemical composition to determine its potential as protein feed.

RESULTS

In a small production system, cultures of Azolla pinnata and Azolla filiculoides were continuously harvested for over 100 days, yielding an average productivity of 90.0–97.2 kg dry weight (DW) ha^?1 d^?1. Under ambient CO₂ levels, N₂ fixation by the fern's cyanobacterial symbionts accounted for all nitrogen in the biomass. Proteins made up 176–208 g kg^?1 DW (4.9 × total nitrogen), depending on species and CO₂ treatment, and contained more essential amino acids than protein from soybean. Elevated atmospheric CO₂ concentrations (800 ppm) significantly boosted biomass production by 36–47%, without decreasing protein content. Choice of species and CO₂ concentrations further affected the biomass content of lipids (79–100 g kg^?1 DW) and (poly)phenols (21–69 g kg^?1 DW).

CONCLUSIONS

By continuous harvesting, high protein yields can be obtained from Azolla cultures, without the need for nitrogen fertilization. High levels of (poly)phenols likely contribute to limitations in the inclusion rate of Azolla in animal diets and need further investigation. © 2018 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

     

Occurrence and fate of carbamazepine,clofibric acid,diclofenac, ibuprofen,ketoprofen, and naproxen in surface waters

Although various single-concentration measurements of pharmaceuticals are available in the literature, detailed information on the variation over time of the concentration and the load in wastewater effluents and rivers and on the fate of these compounds in the aquatic environment are lacking. We measured the concentrations of six pharmaceuticals, carbamazepine, clofibric acid, diclofenac, ibuprofen, ketoprofen, and naproxen, in the effluents of three wastewater treatment plants (WWTPs), in two rivers and in the water column of Lake Greifensee (Switzerland) over a time period of three months. In WWTP effluents, the concentrations reached 0.95 microg/L for carbamazepine, 0.06 microg/L for clofibric acid, 0.99 microg/L for diclofenac, 1.3 microg/L for ibuprofen, 0.18 microg/L for ketoprofen, and 2.6 microg/L for naproxen. The relative importance in terms of loads was carbamazepine, followed by diclofenac, naproxen, ibuprofen, clofibric acid, and ketoprofen. An overall removal rate of all these pharmaceuticals was estimated in surface waters, under real-world conditions (in a lake), using field measurements and modeling. Carbamazepine and clofibric acid were fairly persistent. Phototransformation was identified as the main elimination process of diclofenac in the lake water during the study period. With a relatively high sorption coefficient to particles, ibuprofen might be eliminated by sedimentation. For ketoprofen and naproxen, biodegradation and phototransformation might be elimination processes. For the first time, quantitative data regarding removal rates were determined in surface waters under real-world conditions. All these findings are important data for a risk assessment of these compounds in surface waters.