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  • Author or Editor: L. Takács x
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Purpose

This study investigated the day-to-day variability of daily physical activity and its effect on sleep and mood in a longitudinal within-subjects study for 7 days and 6 nights.

Materials and methods

Healthy office employees aged 25–35 years with a sedentary lifestyle participated in the study. Seven-day sleep diaries were used to evaluate sleep patterns. Ten-point scales were used to measure the level of happiness and stress. Daily physical activity was measured in steps/day using pedometers. Two hundred forty-five steps/day scores and changes induced in sleep and mood were analysed.

Results

There is a relationship between daily physical activity and sleep/mood. An inverted U-shaped relationship may be assumed between sleep duration, sleep quality, feelings after waking up, and the number of steps/day. Increasing the number of steps/day decreases the level of stress and daytime sleepiness and increases sleep efficiency. Sleep efficiency/daytime sleepiness and sleep duration did not show any association.

Conclusions

Based on the results, after a physically exhausting day, decreased stress and improved sleep efficiency may be experienced, while sleep duration may decrease, which may reduce the participants’ motivation to develop an active lifestyle. For further studies, it would be crucial to use individual exercise intervention programmes to reinforce the positive effects of exercise on sleep and/or mood.

Open access

Abstract  

The reactions of hydroxyl radical and hydrated electron intermediates of water radiolysis were studied in the radiolytic degradation of 2,4-dichlorophenoxyacetic acid (2,4-D) at pH values of 4, 6 and 8. The hydrated electron reactions are also suggested to contribute to the aromatic ring decomposition in addition to the highly effective hydroxyl radical reactions. The experimental results suggest also some contribution from the O2 −•/HO2 pair to the degradation. The degradation efficiency was found to be the highest at pH 8 and the lowest at pH 6.

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In our investigations the membrane filtration of quality wines (Tokaji Hárslevelű and Egri Bikavér) — based on diafiltration principles, applying nanofiltration membranes — has been studied. For the diafiltration experiments a relatively dense nanofiltration membrane NF 45 has been used, while for simple wine concentrations a membrane developed for organic components rejection NF200 has been investigated. The mixture of the retarded wine compounds was considered the main product of the process. The permeate that crossed the membrane was handled as the by product. Separated wine samples and the original wines have been subjected to gas chromatographic analysis: according to the results the partition of the main components and aroma compounds of the samples was approximately equal between the main and by-product. Membrane separation has been applied in accordance with a “prelaborated” experimental plan, when completing it the effect of operational parameters on the effectiveness of the process has been evaluated and analysed. By mathematical modelling of the phenomenon empirical and quasiempirical relations were set up, and solutions for the practical realization of the procedure were searched for. Our new model describes the filtration efficiency with our new index in the function of the operational parameters’ influence. The significance of the relation is, that the knowledge of the wine-constants might promote the expedient choice of the membrane, which is a primary aspect in planning and creating the process optimal.

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Abstract  

Liquids and solutions containing Mössbauer active isotopes when trapped in the capillaries of porous silicate glasses show the Mössbauer effect1 also at room temperature2,3. A model is given for the explanation of this phenomenon.

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It has been proved that because of the different past of the parcels regarding their soil, agronomical and technological parameters, weed sampling results may not be generalised. Therefore it is necessary to study those solutions how to determine on an acceptable confidence level a parcel’s weed infestation with optimised sampling techniques.For studying the question we have delimited on wheat stubble a total sample area of 36×54 metres (using it as reference) and divided it into 2×2 cells giving a total of 486 sample cells. Then we surveyed the weed infestation and GPS recorded the location of each cell.We have analysed the weed infestation data with mathematical and statistical methods comparing the results of cells with each other and with the total sample area. We found that in several cases of different sample cells weed infestation displayed a diverse picture. This way sampling of weeds is extremely difficult.We found close relation between relative frequency of weeds and sampling accuracy. Therefore sampling is reliable only for surveying the frequent weeds in a parcel, while more rarely found weeds (e.g. spots of perennials) are to be scouted only by means of going over the parcel and GPS recording them. Otherwise, in the case of a traditional sampling process, the number of sampling cells required for acceptable reliability is unnecessarily high.Consequently, it is necessary to further study the economic and cost efficiency aspects of the needed weed sample density from the point of view of reasonable sample density, accuracy and optimal yield.

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The teratogenic effects of lead acetate (Trial 1) and the possible teratogenic effect of this compound administered in combination with a fungicide containing 80% mancozeb (Trial 2) were studied in rats. The test substances were administered by gavage on Days 6-15 of gestation. In Trial 1, five groups were treated with lead acetate administered at doses of 0.1, 0.5, 1.0, 10.0 and 1000.0 mg/kg body weight (bwkg), respectively. In Trial 2, lead acetate was applied at doses of 0.1, 10.0 and 1000.0 mg/bwkg, respectively. In the latter case the dose of the pesticide was 750 mg/bwkg in all treated groups. Lead acetate was not teratogenic after a single administration. Combined administration of lead acetate and mancozeb gave rise to the following toxic effects: average maternal weight decreased during pregnancy, the ratio of live fetuses decreased after the two lowest doses, and fetal mortality increased in the lowest and in the highest dose groups. The ratio of fetal resorption was higher in all the treated groups than in the control group. A significant decrease occurred in average fetal and placental weight in each treated group as compared to the control. Maternal toxicity was expressed in paralysis of the hindlimbs in the two lowest dose groups. Maternal mortality was between 16.7 and 23.3% at the three dose levels. Phocomelia and hernia cerebri occurred as characteristic fetal developmental anomalies in all the treated groups. It is concluded that the joint administration of lead acetate and a mancozeb-containing fungicide can cause maternal toxicity, embryotoxicity and characteristic teratogenic effects.

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