The effect of tonsillectomy on the level of circulating immune complexes and urine changes in patients with glomerulonephritis

The influence of tonsillectomy on circulating immune complexes (C.I.C.) level, proteinuria and erythrocyturia was studied in 42 patients with chronic tonsillitis (Ch.T.) and urine abnormalities. The level of C.I.C. was examined by two methods: the 3.5% polyethyleneglycol (PEG) precipitation method and the 125I-C1q binding method. After tonsillectomy, bacteriological analysis of removes facial tonsilla was performed in 7 patients and morphological analysis in 11. Renal biopsy was done in 28 patients. The control group was consisted of 18 patients with Ch.T. without urine abnormalities. The presence of C.I.C. was established in 48% of patients with urine abnormalities using PEG method and in 33% with 125I-C1q binding method. Mean values of C.I.C. in patients with proteinuria or erythrocyturia were statistically higher than in the control group. After tonsillectomy, transitory increase of C.I.C. level was observed in 60% of patients, accompanied by augmentation in urine changes, especially proteinuria. During one year of observation, significant decrease in C.I.C. levels detected by PEG method, as well as in proteinuria and in erythrocyturia was found. In 10 patients urine abnormalities disappeared. No differences between both groups of patients were found in the results of bacteriological and morphological studies of removed tonsilla. However, the normalisation of urine changes was noticed in patients without hypertension and in whom renal disease did not exceed two years. Renal histology revealed mesangocapillary proliferative Gn in 14, mesangial proliferative Gn in 11, and focal/segmental glomerulosclerosis in 3 patients. In one patient with mesangial proliferative Gn complete retreat of urine changes was observed. We suggest that the presence of Ch.T. influences on the C.I.C. detectability in patients with chronic glomerulonephritis. The tonsillectomy can lead do the decrease of C.I.C. levels, as well as to the decrease of proteinuria and/or erythrocyturia. Serum C.I.C. examination seems to be helpful in qualifying patients with Ch.T. for tonsillectomy, in immunological monitoring after the operation and in later prognosis in case of chronic glomerulonephritis.     

The approximate swap and mismatch edit distance

There is no known algorithm that solves the general case of the approximate edit distance problem, where the edit operations are insertion, deletion, mismatch, and swap, in time o(nm), where n is the length of the text and m is the length of the pattern.In the effort to study this problem, the edit operations have been analyzed independently. Karloff [10] showed an algorithm that approximates the edit distance problem with only the mismatch operation in time . Amir et al. [4] showed that if the only edit operations allowed are swap and mismatch, then the exact edit distance problem can be solved in time .In this paper, we discuss the problem of approximate edit distance with swap and mismatch. We show a randomized time algorithm for the problem. The algorithm guarantees an approximation factor of (1+?) with probability of at least .     

Class Constrained Bin Covering

We study the following variant of the bin covering problem. We are given a set of unit sized items, where each item has a color associated with it. We are given an integer parameter k≥1 and an integer bin size B≥k. The goal is to assign the items (or a subset of the items) into a maximum number of subsets of at least B items each, such that in each such subset the total number of distinct colors of items is at least k. We study both the offline and the online variants of this problem. We first design an optimal polynomial time algorithm for the offline problem. For the online problem we give a lower bound of 1+H _k−1 (where H _k−1 denotes the (k−1)-th harmonic number), and an O(k)-competitive algorithm. Finally, we analyze the performance of the natural heuristic First fit.     

Visible light-induced charge retention and photocatalysis with hybrid CdSe-Au nanodumbbells

Visible light photocatalysis is a promising route for harnessing of solar energy to perform useful chemical reactions and to convert light to chemical energy. Nanoscale photocatalytic systems used to date were based mostly on oxide semiconductors aided by metal deposition and were operational only under UV illumination. Additionally, the degree of control over particle size and shape was limited. We report visible light photocatalysis using highly controlled hybrid gold-tipped CdSe nanorods (nanodumbbells). Under visible light irradiation, charge separation takes place between the semiconductor and metal parts of the hybrid particles. The charge-separated state was then utilized for direct photoreduction of a model acceptor molecule, methylene blue, or alternatively, retained for later use to perform the reduction reaction in the dark.     

Thermo-economic analysis of an ocean thermal power plant for a Nigerian coastal region

This paper presents a thermo-economic analysis of an ocean thermal energy conversion (OTEC) power plant for a Nigerian coastal region at latitude 4°00′–4°16′N, and longitude 7°16′–7°19′E, whose energy potential is at 22 and 24?K across 1?km from the sea water surface during rainy and dry seasons, respectively. An ammonia closed cycle OTEC plant was designed to constantly supply 100?MW of electricity all year round to the region. The results of the analysis compared favourably with those for similar plants. The plant’s unit cost of energy was found to be 0.11US$/kWh when compared to 0.1US$/kWh for the municipal energy supply. The break-even point was also found to be 12 years. However, as a result of the high initial installed capital cost of 7954.37US$/kW and life cycle cost of 1.30bUS$, only very large organisations would be able to venture into this project.     

Adsorption of berberine on commercial minerals

There is interest in studying interactions between organic modifiers and raw commercial clays aiming the production of low-cost “organoclays”. In this study we report the interaction between berberine — a monovalent organic cation — and three commercial bentonites and a Turkish zeolite. The Turkish zeolite exhibited adsorption at values of 5–10% of the cation exchange capacity (CEC) with no neutralization of the particles. Adsorption of the organo-cation on Egyptian bentonite, Volclay KWK and Pure-Flo B80, was above the CEC of the bentonites, yielding neutral and even slightly positively charged particles. Electron microscopy and X-ray diffraction results showed expansion of the basal spacing of the smectite. Such low-cost organo-bentonites might be suitable for environmental applications as removal of pollutants, drug and pesticides delivery, or water treatment. Application in turbidity reduction of industrial effluents is demonstrated.     

Minimizing crosstalk in three-axial induction magnetometers

A model for crosstalk in three-axial induction magnetometers has been developed theoretically and verified experimentally. The effect of crosstalk on the magnetometer accuracy has been analyzed. It has been found that the inevitable crosstalk in the transverse coils has two components: one due to the applied magnetic flux and the other due to the secondary flux produced by the electric current in the longitudinal coil. The first component has a constant magnitude. The phase of the second component, relative to the first one, is nearly 180° at low frequencies, 90° at resonance, and 0° at high frequencies. Its magnitude approaches zero at low frequencies, has the maximum at resonance, and then drops off by a factor equal to the coils' quality factor and approaches the first component value. As a result, the crosstalk due to the applied flux is dominant at low frequencies. At a frequency just below the resonance, the crosstalk is very low, if no magnetic feedback is applied. Just above the resonance, the crosstalk reaches the maximum because of the rapid increase in the secondary flux. Applying a strong enough magnetic feedback nearly flattens the crosstalk amplitude response. However, an undesirable effect of the feedback is that it significantly increases the minimum crosstalk value. A very low crosstalk at a single frequency can be beneficial for magnetometers tuned to a narrow frequency band. It can also be beneficial for wide-band magnetometers to measure their mechanical orthogonality with a minimum effect of crosstalk.     

The impact of cemented layers and hardpans on oxygen diffusivity in mining waste heaps A field study of the Halsbrücke lead-zinc mine tailings (Germany)

This article reports fibre-optic oxygen measurements on a reactive mine waste heap located in the polymetallic sulphide mine district of Freiberg in south-eastern Germany. The heaped material consists of sulphide-bearing tailings from a processing plant of a lead-zinc mine. Mine waste material was deposited in the water phase after separation of mining ores in a flotation process. The tailing impoundment is partly covered with coarse sand and topsoil. Oxygen profiles were monitored during one year at eleven locations showing different physical and mineralogical compositions. At each location a borehole was drilled where the optic sensors were installed at 2-5 different depths. After installation the oxygen profiles were monitored seven times during one year from 2006-2007 and three to five oxygen profiles at each location were obtained. Oxygen measurements were accompanied by physical, chemical and mineralogical data of the tailing material. Additionally, a detailed mineralogical profile was analysed at a location representative for the central part of the heap, where the cemented layers show lateral continuity. Results showed that cemented layers have a significant influence on natural attenuation of the toxic As and Pb species owing to their capacity of water retention. The measured oxygen profiles are controlled by the zone of active pyrite weathering as well as by the higher water content in the cemented layers which reduces gaseous atmospheric oxygen supply. In contrast, gypsum bearing hardpans detected at three other locations have no detectable influence on oxygen profiles. Furthermore, the grain size distribution was proved to have a major effect on oxygen diffusivity due to its control on the water saturation. Temporal changes of the oxygen profiles were only observed at locations with coarse sediment material indicating also an important advective part of gas flux.