Is dark matter real or just a convenient hypothesis? Although it was first proposed almost a century ago, physicists have yet to uncover its true nature. Scientists from the Nicolaus Copernicus University are investigating the phenomenon using atomic clocks.
Studies were carried out from December 1978 till February 1979. Quantities of suspended matter in the waters of Admiralty Bay ranged from 2.8 to 182.6 mg/1. The maximum quantities of suspended matter were recorded in the inshore zone, in particular at the mouths of the streams running off from the pielting glaciers. In the open regions of Admiralty Bay the average quantities of suspended matter were: 12.4 mg/1 in the upper water-layers, from 14.9 to 16.7 at the depth of 10-50 m and less than 10 mg/1 in deeper water-layers. The quantity of suspended matter drifting from the land into Admiralty Bay during austrial summer was estimated as averaging about 2000 tons per day.
The paper presents the results of experiments on the influence of the organic matter’s characteristics on the formation potential of water chlorination by-products – representatives of the following groups:
trihalomethanes, haloacetonitriles, haloketones, chloral hydrate and chloropicrin. The products of water fractionation (the hydrophobic and hydrophilic acids, hydrophobic and hydrophilic bases, and hydrophobic and
hydrophilic neutral fractions) were chlorinated with sodium hypochlorite. Its dose was adjusted to obtain a
residual free chlorine concentration between 3 and 5 mg/dm3
after 24 h. After this time, the water chlorination
by-products were analyzed with gas chromatography. The results’ analysis has defined the fractions, which have
the highest potential to form particular groups of volatile organic water chlorination by-products.
The paper addresses the effect of a compost prepared from tobacco wastes with an admixture of bark and straw on the enzymatic activity and certain chemical properties of a grey-brown podzolic soil amended with that compost.
The study was conducted under the conditions of a pot experiment in which the soil material was collected from the surface horizon of the grey-brown podzolic soil. The effect of the application of the compost was compared with soil without such amendment. The test plant was maize cv. Kosmo 230. Fertilisation of the light soil with the compost studied caused changes in the enzymatic activity of the soil that were related both to the dose of the compost and to the kind of enzyme studied. With increase in the dose of the compost there was an increase in dehydrogenase activity (highest dose) and a significant decrease in the activity of acid phosphatase. Moreover, it was observed that tobacco compost was a significant source that enriched the light soil in organic matter, total nitrogen, and available forms of phosphorus, magnesium and potassium, which was evident in increased yields of maize grown as the test plant.
Significant correlations were also demonstrated between a majority of the biochemical and chemical parameters, which indicates that those parameters characterise well the biological properties of a grey-brown podzolic soil amended with tobacco compost.
Controlling low-temperature drying facilities which utilise nonprepared air is quite difficult, due to very large variability of ventilation air parameters - both in daily and seasonal cycles. The paper defines the concept of cumulative drying potential of ventilation air and presents experimental evidence that there is a relation between this parameter and condition of the dried matter (sewage sludge). Knowledge on current dry mass content in the dried matter (sewage sludge) provides new possibilities for controlling such systems. Experimental data analysed in the paper was collected in early 2012 during operation of a test solar drying facility in a sewage treatment plant in Błonie near Warsaw, Poland.
The article presents research results of the introduction of powdery activated carbon to the existing technological system of the groundwater treatment stations in a laboratory, pilot plant and technical scale. The aim of the research was to reduce the content of organic compounds found in the treated water, which create toxic organic chlorine compounds (THM) after disinfection with chlorine. Nine types of powdery active carbons were tested in laboratory scale. The top two were selected for further study. Pilot plant scale research was carried out for the filter model using CWZ-30 and Norit Sa Super carbon. Reduction of the organic matter in relation to the existing content in the treated water reached about 30%. Research in technical scale using CWZ-30 carbon showed a lesser efficiency with respect to laboratory and pilot-plant scale studies. The organic matter decreased by 15%. Since filtration is the last process before the individual disinfection, an alternative solution is proposed, i.e. the second stage of filtration with a granular activated carbon bed, operating in combined sorption and biodegradation processes. The results of tests carried out in pilot scale were fully satisfactory with the effectiveness of 70–100%.
The article concerns fly ashes generated from the combustion of hard coal and deposited on landfills. Investigation results describing fly ash taken from a combustion waste landfill are presented in the article. The investigation results indicate a possibility for combusting the coal reclaimed by separation from the fly ash and utilizing the remaining fly ash fractions.
Biology is a science on life. This definition, concise and most commonly used, is satisfactory for almost everybody. It is otherwise when one asks: What is life? Then it appears that no one feature can be indicated which distinguishes “the living” from “the non-living.” The author presents the sources of these difficulties and then gives his own attempt to solve the problem of definition of live—which is based on the idea of levels of the biological organization. In author’s view, to characterise the objects of research in biology we should apply not one concept of life (or of living organism) but three concepts: of organized biological matter (for the molecular and sub-cellular levels), of living organism (for the level of the specimen), and of life (for the sphere of phenomena which occur on the population-species-biocenotic level).
One of the fundamental problems in evolutionary sciences is the direction of evolution at different levels of matter organization. According to traditional teleological interpretations, the evolving systems should develop toward a final state—a goal. However, in most cases such a goal is not determinable—scientists do not know it. However, they can reveal a general tendency or a series of changes in time: a teleonomy or a directness based mainly upon an internal pattern of the evolving system although modified also by external influences. Teleonomical processes are responsible for all evolutionary processes including transitions from one level of organization to another.
The brain is subject to damage, due to ageing, physiological processes and/or disease. Some of the damage is acute in nature, such as strokes; some is more subtle, like white matter lesions. White matter lesions or hyperintensities (WMH) can be one of the first signs of micro brain damage. We implemented the Acoustocerebrography (ACG) as an easy to use method designed to capture differing states of human brain tissue and the respective changes.
Aim: The purpose of the study is to compare the efficacy of ACG and Magnetic Resonance Imaging (MRI) to detect WMH in patients with clinically silent atrial fibrillation (AF).
Methods and results: The study included 97 patients (age 66.26 ± 6.54 years) with AF. CHA2DS2-VASc score (2.5 ±1.3) and HAS BLED (1.65 ± 0.9). According to MRI data, the patients were assigned into four groups depending on the number of lesions: L0 – 0 to 4 lesions, L5 – 5 to 9 lesions, L10 – 10 to 29 lesions, and L30 – 30 or more lesions. Authors found that the ACG method clearly differentiates the groups L0 (with 0–4 lesions) and L30 (with more than 30 lesions) of WMH patients. Fisher’s Exact Test shows that this correlation is highly significant (p < 0:001).
Conclusion: ACG is a new, easy and cost-effective method for detecting WMH in patients with atrial fibrillation