77 research outputs found

    Analysis of the blast-induced vibration structure in open-cast mines

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    Blasting in opencast mines is characterized by the use of large masses of explosives for a single blast. Blasting is done in a series of several to tens or even hundreds of charges placed in long holes and fired with a millisecond delay. Works are often carried out in the vicinity of buildings; therefore, reducing vibration impact is essential for opencast mines. This paper presents the applicability of the method of time-frequency Matching Pursuit (MP) for analysis of vibration structure. The use of MP analysis enables the development of much deeper and more reliable impact assessments of blasting on the environment

    Participation of various habitat groups in the flora of spring niches in the Ojców National Park (Southern Poland)

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    The paper presents composition of vascular plant species in spring niches in the Ojców National Park (Southern Poland). 111 species of vascular plants, fourteen mosses, two liverworts and one species of ferns were recorded during the first comprehensive study carried out in 2009 and 2010. Plants occurring in these places showed different degrees of association with spring niches. The largest group was represented by accidental krenophytes (74 species), while spring plants – obligatory krenophytes, constituted only a small part of the local flora (5 species). Meadow species of the Molinio-Arrhenatheretea class and forest species of the Querco-Fagetea class, penetrating niche areas from the adjacent areas, were the dominating ones. Plants of aquatic and spring communities were scarce, due to the predominance of small type karst springs. The diversity of vegetation was significantly influenced by habitat factors such as availability of light, humidity or the amount of organic matter in the soil

    Method for studying the structure of blast-induced vibrations in open-cast mines

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    Detonations of explosive material charges are a source of intense paraseismic vibrations. These vibrations can cause damage to buildings and other infrastructure in the vicinity of the works, and can be a nuisance for their inhabitants. The article presents the problem of paraseismic vibration analysis, as induced by blasting works carried out in open-cast mines, using various methods of time – frequency, providing information about the duration of the signal, the frequency structure, and its energy

    Biological Traits of Impatiens parviflora DC. under Different Habitat Conditions

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    Small balsam Impatiens parviflora DC. (Balsaminaceae) is the invasive species that colonises natural European forest. The morphological and physiological traits of the species under different natural conditions were analysed. The studies were carried out in the forest communities in the National Park (Ojców National Park – Southern Poland) with the known history of the plot: P1 – bottom of the valley, Alno-Ulmion Br.-Bl. et R.Tx. 1943, P2 – terrace of the valley, Tilio-Carpinetum Tracz. 1962 stachyetosum, P3 – south slope of the valley, Tilio-Carpinetum Tracz. 1962 typicum. The plots differed with the soil parameters and microclimatic conditions as well as with species richness, species composition and cover of I. parviflora. The significant statistical differences in the length of the aboveground parts of collected small balsam specimens on the studied plots were showed. The longest shoots among specimens growing in plot P1, and the shortest in plot P3 were observed. In the above ground part of plants, the highest values of water content among the specimens on plot P1 and the lowest on plot P3 were revealed. The highest percentage of electrolytes leakage among the specimens from the plot P2 and the lowest of the plot P1 were observed. The significant differences of the chlorophyll a fluorescence of I. parviflora leaves on the plot P2 were observed, compared to specimens from the two remaining plots. The results pointed that disturbance light availability in dense forest canopy could influence on abundance the local population of small balsam

    Biological traits of impatiens parviflora DC. under different habitat conditions

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    Small balsam Impatiens parviflora DC. (Balsaminaceae) is the invasive species that colonises natural European forest. The morphological and physiological traits of the species under different natural conditions were analysed. The studies were carried out in the forest communities in the National Park (Ojców National Park - Southern Poland) with the known history of the plot: P1 - bottom of the valley, Alno-Ulmion Br.-Bl. et R.Tx. 1943, P2 - terrace of the valley, Tilio-Carpinetum Tracz. 1962 stachyetosum, P3 - south slope of the valley, Tilio-Carpinetum Tracz. 1962 typicum. The plots differed with the soil parameters and microclimatic conditions as well as with species richness, species composition and cover of I. parviflora. The significant statistical differences in the length of the aboveground parts of collected small balsam specimens on the studied plots were showed. The longest shoots among specimens growing in plot P1, and the shortest in plot P3 were observed. In the underground part of plants, the highest values of water content among the specimens on plot P1 and the lowest on plot P3 were revealed. The highest percentage of electrolytes leakage among the specimens from the plot P2 and the lowest of the plot P1 were observed. The significant differences of the chlorophyll a fluorescence of I. parviflora leaves on the plot P2 were observed, compared to specimens from the two remaining plots. The results pointed that disturbance light availability in dense forest canopy could influence on abundance the local population of small balsam

    Effect of Aqueous Extracts of Sticky Willy (Galium aparine L.) on the Growth of Seedlings of Selected Maize Varieties (Zea mays L.)

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    In the environment plants are competing for water, nutrients and light, and other components. Their competition is not only based on shading but on the allelopathic interactions as well. Sticky willy (Galium aparine L.) is a nitrophilous weed growing in thickets, crop fields and on ruderal areas. Its sticky and strongly branching stems are connecting together stalks of grain make it difficult to harvest. G. aparine wraps around plants and limits their access to the light. It may to secrete allelopathic substances to the soil. The aim of this study was to determine the effect of aqueous extracts from shoots G. aparine L. concentrations of 1, 3, and 5% on growth seedlings of Zea mays L. in two varieties: ‘Lokata’ F2, ‘Wilga’ F1 and F2. The seeds were placed on Petri dishes (100 units) and watered extracts from shoots G. aparine, and distilled water (control). The ability of seed germination was higher on extracts of concentration 1% for the variety ‘Wilga’ F1 and F2, and less for the ‘Lokata’ F2. Biometric analysis of seedling roots showed the stimulatory effect of 1% and 3% extracts, and the inhibitory for 5%. The fresh weight of maize seedlings was significantly higher on 1% extract, as compared to other and the control. The values of the dry weight of ‘Lokata’ F2 each concentration was lower in comparison to the control. The water contents in seedlings of the ‘Wilga’ F1 and ‘Lokata’ F2 varieties were significantly increased of each extracts, in comparison to control

    Determinants of acceptance of the illness by hemodialysis patients

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    Treated hemodialysis patients with chronic renal failure in everyday life experience many of the restrictions and requirements on the part of the disease, which is, in many ways, difficult to accept. The aim of the study was to diagnose the illness acceptance rate and understanding the role of socio- -demographic variables and variables specific to renal replacement therapy, and styles of coping with stress for the differentiation of the acceptance of the disease in patients with chronic renal failure undergoing hemodialysis. In the study 100 patients participated. The Acceptance of Illness Scale and Questionnaire Coping with Stressful Situations were used as well as own questionnaire which contained questions related to socio-demographic data and certain aspects of the disease and treatment. Acceptance rate of the disease among the patients on hemodialysis was 22.76 (SD = 5.33). It has been shown a positive correlation between the level of acceptance of the disease and variables such as male gender, higher level of education, positive assessment of material situation, the feeling better between dialysis and its shorter total duration and also between coping style in patients with stress concentrated on the task or avoidance. The analysis of data from the study suggests the need to take into account the problem of acceptance of the disease by hemodialysis patients and occurrence of factors that differentiate in a positive or negative way the degree of acceptance of the disease at all stages of its duration

    Relationship between neurological and cerebellar soft signs, and implicit motor learning in schizophrenia and bipolar disorder

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    Background: Schizophrenia (SZ) and bipolar disorder (BD) patients share deficits in motor functions in the form of neurological (NSS) and cerebellar soft signs (CSS), and implicit motor learning disturbances. Here, we use cluster analysis method to assess (1) the relationship between those abnormalities in SZ and BD and (2) the differences between those groups. Methods: 33 SZ patients, 33 BD patients as well as 31 healthy controls (HC) took part in the study. We assessed CSS with the International Cooperative Ataxia Rating Scale (ICARS) and NSS with the Neurological Evaluation Scale (NES). Implicit motor learning was evaluated with the Serial Reaction Time Task (SRTT). Participants were divided into clusters (Ward's method) based on the mean response time and mean error rate in SRTT. The difference in ICARS and NES scores, and SRTT variables between clusters were evaluated. We have measured associations between SRTT parameters and both ICARS and NES total scores and subscores. Results: Cluster analysis based on the SRTT parameters allowed to extract three clusters. Those were characterized by the increasing disruption of motor functioning (psychomotor retardation, the severity of NSS and CSS) regardless of the diagnosis. Cluster 1 covered almost all of HC and was characterized by faster reaction times and small number of errors. BD and SZ patients represented in cluster 1, although fully functional in performing the SRTT, showed higher rates of NSS and CSS. Patients with BD and SZ were set apart in clusters 2 and 3 in a similar proportion. Cluster 2 presented significantly slower reaction times but with the comparable number of errors to cluster 1. Cluster 3 consisted of participants with normal or decreased reaction time and significantly increased number of errors. None of the clusters were predominantly composed of the patients representing one psychiatric diagnosis. Conclusions: To our best knowledge, we are presenting the first data indicating the relationship between implicit motor learning and NSS and CSS in SZ and BD patients' groups. Lack of clusters predominantly represented by patients with the diagnosis of SZ or BD may refer to the model of schizophrenia-bipolar disorder boundary, pointing out the similarities between those two disorders

    Erythema nodosum as a manifestation of many systemic diseases

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    Introduction and purpose: Erythema nodosum is a most frequent form of panniculitis and it appears as erythematous, painful rounded, nodules typically localized on the pretibial area. The purpose of our review is to present diseases that can be underlying causes of erythema nodosum and to draw attention to accompanying symptoms that can guide us to the appropriate diagnosis. Brief description of the state of knowledge: Currently, erythema nodosum is thought to be a symptom associated with hypersensitivity reactions to various antigens. Although the majority of the causes are considered idiopathic, erythema nodosum may be caused by many etiological factors. Summary: Erythema nodosum is usually an acute condition that resolves without treatment. However, it can sometimes be the first sign of a serious condition - autoimmune diseases, infections or malignancy. In such cases it is essential to observe it carefully and implement appropriate diagnostics that allow us to make a correct diagnosis
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