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1.
PLoS One ; 19(5): e0303606, 2024.
Article in English | MEDLINE | ID: mdl-38781133

ABSTRACT

The paper presents the results of research on the influence of risk factors on the implementation of railway investments in Poland (build stage) and deals with a detailed diagnosis of relation between factors. The application of DEcision MAking Trial and Evaluation Laboratory (DEMATEL) method for the analyses allowed to develop a cause-and-effect model of key factors and analyse the importance of the factors. Eleven factors identified in eariel studies as the most important risk factors were examined. It was found that the factors: errors in the preparation of tender documents (10.38%), errors in project documentation (10.02%), improperly estimated time of completion of the investment by the Employer (9.82%), internal regulations of PKP Polskie Koleje Panstwowe S.A. (Polish State Railways) not coordinated with the provisions of contracts (9.51%) have the highest degree of importance. Factors: too many external institutions involved in the investment process and internal regulations of PKP Polskie Koleje Panstwowe S.A. (Polish State Railways) not coordinated with the provisions of contracts, have the greatest net impact on the other factors. The relations between the factors and factors importance are valuable knowledge for engineers, enabling the project to be implemented according to the planned schedule and investment cost.


Subject(s)
Investments , Railroads , Poland , Risk Factors , Humans , Investments/economics , Decision Making
2.
Int J Mol Sci ; 24(5)2023 Feb 23.
Article in English | MEDLINE | ID: mdl-36901877

ABSTRACT

A very low concentration of manganese (Mn) in water is a critical issue for municipal and industrial water supply systems. Mn removal technology is based on the use of manganese oxides (MnOx), especially manganese dioxide (MnO2) polymorphs, under different conditions of pH and ionic strength (water salinity). The statistical significance of the impact of polymorph type (akhtenskite ε-MnO2, birnessite δ-MnO2, cryptomelane α-MnO2 and pyrolusite ß-MnO2), pH (2-9) and ionic strength (1-50 mmol/L) of solution on the adsorption level of Mn was investigated. The analysis of variance and the non-parametric Kruskal-Wallis H test were applied. Before and after Mn adsorption, the tested polymorphs were characterized using X-ray diffraction, scanning electron microscope techniques and gas porosimetry analysis. Here we demonstrated the significant differences in adsorption level between MnO2 polymorphs' type and pH; however, the statistical analysis proves that the type of MnO2 has a four times stronger influence. There was no statistical significance for the ionic strength parameter. We showed that the high adsorption of Mn on the poorly crystalline polymorphs leads to the blockage of micropores in akhtenskite and, contrary, causes the development of the surface structure of birnessite. At the same time, no changes in the surfaces of cryptomelane and pyrolusite, the highly crystalline polymorphs, were found due to the very small loading by the adsorbate.


Subject(s)
Manganese , Oxides , Oxides/chemistry , Manganese Compounds/chemistry , Oxidation-Reduction , Water/chemistry , Adsorption
3.
J Prim Care Community Health ; 13: 21501319221106625, 2022.
Article in English | MEDLINE | ID: mdl-35726205

ABSTRACT

War refugees and veterans have been known to frequently develop neuropsychiatric conditions including depression, post-traumatic stress disorder (PTSD), and anxiety disorders that tend to leave a long-lasting scar and impact their emotional response system. The shear stress, trauma, and mental breakdown from overnight displacement, family separation, and killing of friends and families cannot be described enough. Victims often require years of mental health support as they struggle with sleep difficulties, recurring memories, anxiety, grief, and anger. Everyone develops their coping mechanism which can involve dependence and long-term addiction to alcohol, drugs, violence, or gambling. The high prevalence of mental health disorders during and after the war indicates an undeniable necessity for screening those in need of treatment. For medical health professionals, it is crucial to identify such vulnerable groups who are prone to developing neuropsychiatric morbidities and associated risk factors. It is pivotal to develop and deploy effective and affordable multi-sectoral collaborative care models and therapy, which primarily depends upon family and primary care physicians in the conflict zones. Herein, we provide a brief overview regarding the identification and management of vulnerable populations, alongside discussing the challenges and possible solutions to the same.


Subject(s)
Psychiatry , Refugees , Stress Disorders, Post-Traumatic , Veterans , Armed Conflicts/psychology , Humans , Refugees/psychology , Stress Disorders, Post-Traumatic/epidemiology , Stress Disorders, Post-Traumatic/therapy
4.
PeerJ ; 10: e13418, 2022.
Article in English | MEDLINE | ID: mdl-35762017

ABSTRACT

Study region: The area of interest is the Upper Biebrza Valley, located in NE Poland. Study focus: We examined water exchange at the river-fen interface in a near-natural wetland system using the combined field research-modeling approach. The authors chose the Biebrza River as the research object: it is a specific case of fen marginal valley rivers, and it flows in the peat layer without direct connection to the mineral soil layer. Our case study introduces two new aspects not yet considered in the scientific literature: (1) the riparian aquifer is fen and (2) the river has no direct contact with the mineral layer. The following research questions were investigated: What is the role of the river in feeding and draining a fen? Which drainage paths are important for water exchange in a near-natural river-fen system? How important are the morphological settings for the river-fen relations? We applied a systematic hydrological research approach based on field measurements and observations of the river and surrounding fen hydrological characteristics, as well as on the modelling results. New hydrological insights for the region: We demonstrated that morphological settings have a significant influence on river-fen relations. We also demonstrated that due to the undeniable need to introduce increased protection and restoration of marginal fens, we may focus on river status in narrow valleys; however, in the wide valleys, the limitation of the drainage layer by decreasing the intensity of evapotranspiration is more promising. We propose to distinguish zones in the fen river valley to include them when proposing protection or conservation plans.


Subject(s)
Groundwater , Wetlands , Rivers , Soil , Water
6.
J Prim Care Community Health ; 13: 21501319221095358, 2022.
Article in English | MEDLINE | ID: mdl-35465746

ABSTRACT

On the 24th of February 2022, the Russian Federation began an unprovoked invasion of Ukraine, marking the biggest military attack in Europe since the second world war. Over 4 million people have fled their homeland within the first month of the war and have triggered a large refugee crisis with impacts far beyond the Ukrainian border. People in the neighboring countries have shown tremendous support by stepping forward to donate food, clothes, medications, money, and other essential supplies. The governments and other regional stakeholders have also been supportive in accommodating and easing regulations for the incoming refugees. Herein, we summarize the humanitarian measures and medical donations that have been made by European countries as they stepped up their efforts to provide refugees with all necessary basic services. We further highlight potential oncoming challenges in Ukraine and the host countries along with relevant solutions to these challenges. The current scenario highlights the need for multi-party and multi-level collaborations (both public and private) to tackle the emerging situation.


Subject(s)
Refugees , Europe , Humans , Medical Assistance , Russia , Ukraine
7.
PLoS One ; 16(9): e0255755, 2021.
Article in English | MEDLINE | ID: mdl-34506486

ABSTRACT

River embankments are the basic and the oldest measures of protecting areas potentially subjected to flooding, and at the same time pose a serious threat to their environment in the event of damage or failure. The technical condition of the levees and its regular evaluation is a key element of their safety. A general assessment of the technical condition of a levee is the result of many interacting factors and parameters that depend on each other to a varying degree. Therefore, it is necessary to consider the cause-and-effect links between the interrelationships of numerous parameters and sensors of significant impact. In this article the decision-making trial and evaluation laboratory (DEMATEL) method was applied to develop a cause-and-effect model for factors impacting the condition and safety of levees. Effective factors impacting the technical condition of a levee were identified; relationships between these factors were determined; a cause-and-effect model was developed based on identified factors; factors were categorized based on the dependence scale and influential indicators of each factors used in the DEMATEL method. The obtained results demonstrate that three following factors: hydrological factor, type and condition of soils in levee body and condition of levee areas (inter-levee and landside) play the most important role for levee safety. The results of this study can support traditional assessments of hydrotechnical structure or assist entities managing levees.


Subject(s)
Algorithms , Decision Making , Decision Support Techniques , Floods/prevention & control , Rivers/chemistry , Computer Simulation , Geologic Sediments/analysis , Models, Theoretical
8.
PeerJ ; 8: e9778, 2020.
Article in English | MEDLINE | ID: mdl-32974093

ABSTRACT

Water plays a key role in the functioning of wetlands and a shortage or contamination of it leads to changes in habitat conditions and degradation of ecosystems. This article scrutinizes the impact of climate change on the hydrological characteristics of floods (maximum flow, duration, volume) in the River Biebrza wetlands (North-East Poland). We analysed the trends in duration and volume of flood and maximum discharges in the historical period 1970-2000 and predicted these for the future periods 2020-2050 and 2070-2100, respectively. Next we assessed the impact on the wetland ecosystems. The basis of our assessments consists of statistical analyses of hydrographs and calculations by the Soil and Water Assessment Tool hydrological model and considering nine bias-corrected climate models. The results indicate that both volume and duration of winter floods will keep increasing continuously under Representative Concentration Pathways 4.5 and 8.5. The reduction in peak annual floods is expected to decline slightly in both scenarios. On the other hand, the analysis of trends in mean and standard deviation revealed negligible tendencies in the datasets for summer and winter hydrological seasons within the three time frames analysed (1970-2000; 2020-2050; 2070-2100). We foresee several future implications for the floodplain ecosystems. Shifts in transversal ecosystem zonation parallel to the river will likely take place with more highly productive flood tolerant vegetation types. Nutrient availability and algal blooms during spring inundations will likely increase. Slowdown of organic matter turnover later in summer will lead to a higher peat accumulation rate. Logistical problems with summer mowing and removal of bushes in winter may enhance shrub encroachment.

9.
PeerJ ; 8: e9275, 2020.
Article in English | MEDLINE | ID: mdl-32612881

ABSTRACT

The progressive degradation of freshwater ecosystems worldwide requires action to be taken for their conservation. Nowadays, protection strategies need to step beyond the traditional approach of managing protected areas as they have to deal with the protection or recovery of natural flow regimes disrupted by the effects of future climate conditions. Climate change affects the hydrosphere at catchment scale altering hydrological processes which in turn impact hydrodynamics at the river reach scale. Therefore, conservation strategies should consider mathematical models, which allow for an improved understanding of ecosystem functions and their interactions across different spatial and temporal scales. This study focuses on an anastomosing river system in north-eastern Poland, where in recent decades a significant loss of the anabranches has been observed. The objective was to assess the impact of projected climate change on average flow conditions in the anastomosing section of the Narew River. The Soil and Water Assessment Tool (SWAT software) for the Narew catchment was coupled with the HEC-RAS one-dimensional unsteady flow model. The study looked into projected changes for two future time horizons 2021-2050 and 2071-2100 under the Representative Concentration Pathway 4.5 using an ensemble of nine EURO-CORDEX model scenarios. Results show that low flow conditions in the anastomosing section of the Narew National Park will remain relatively stable in 2021-2050 compared to current conditions and will slightly increase in 2071-2100. Duration of low flows, although projected to decrease on an annual basis, will increase for August-October, when the loss on anastomoses was found to be the most intense. Hydraulic modeling indicated extremely low flow velocities in the anastomosing arm (<0.1 m/s) nowadays and under future projections which is preferable for in-stream vegetation development and their gradual sedimentation and closure.

10.
Environ Monit Assess ; 188(11): 625, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27757828

ABSTRACT

In our study, we analyzed the combined standard uncertainty of water table slope assessment done using differential global positioning system (DGPS)-based measurements of water table elevation and distances between measurement locations. We compared and discussed uncertainties in water table slope assessments done in various hypothetical environments of lowland floodplains (water table slopes typically ranged from 1.25 · 10-4 to 1 · 10-3). Our analyses referred to elevation measurements done with the static GPS and DGPS real-time kinematic (RTK) approaches, which are currently among the most frequently used elevation measurement techniques worldwide. Calculations of the combined standard uncertainty of water table slope allowed us to conclude that the DGPS-RTK approach used in water table slope assessment can result in assessment errors as high as 50 % at short (<200 m) distances. Acceptable water table slope measurement errors (lower than 5 %) occur at distances longer than 11,320 m in the case of DGPS-RTK measurements, while, in the case of static GPS measurements, acceptable measurement errors at the same level occur at distances as low as 1350 m. Errors in water table slope assessment as high as 50 % occur at distances of 1130 m and 140 m for DGPS-RTK and static GPS measurements, respectively. We conclude that, although the DGPS-RTK methodology-due to its ease of use and time-saving capabilities is very often applied to water level measurements in lowland riparian wetlands, the application of the DGPS-RTK methodology for water table slope assessment at distances shorter than a few couples of meters results in very low accuracy (errors greater than 50 %) and should not be used for calculating local slopes in low slope areas such as lowland riparian zones.


Subject(s)
Groundwater , Wetlands , Geographic Information Systems , Uncertainty
11.
J Environ Manage ; 152: 230-40, 2015 Apr 01.
Article in English | MEDLINE | ID: mdl-25682202

ABSTRACT

A multi-model-based study was performed in order to unravel valuable fen meadow habitats' possible exposure to eutrophication, which is expected to occur as a result of the re-saturation of degraded peat soils. The framework was tested in a 3000-ha fen-drain system to be restored in the Middle Biebrza Basin (northeast Poland), where the datasets and related models were used to delineate prospective eutrophication hotspots and nutrient transport. A 1-d hydrodynamic model and a 3-d groundwater flow model were applied to constitute the hydrological response of the fen-drain system to the prospective construction and function of weirs and spillways, which are expected to induce the increase of groundwater levels in degraded fens. A groundwater particle-tracking postprocessor was applied to delineate flow pathways and discharge zones and to determine water residence time in modelled layers. Soil and habitat maps, a high-resolution digital elevation model and historic groundwater level observations were applied to the model performance, calibration and spatial analysis of prospective eutrophication hotspots where increased eutrophication of groundwater can be expected due to the re-saturation of degraded peat soils. The study revealed that the large-scale fen rewetting that occurred as a result of surface water bodies' damming can potentially result in groundwater-driven nutrient dispersion along with an enhanced nutrient transport from a fen to the adjacent water bodies. Spatial analyses showed that, although the rewetting-driven eutrophication of Molinia fen meadows located in the study area is not likely, one can expect increased nutrient discharges to adjacent drains, inducing the contamination of ox-bow lakes located along the rivers. We propose the presented methodology to be applied ex-ante to fen-rewetting projects in strategic environmental assessments of restoration projects in order to manage the potentially negative environmental consequences of fen and river eutrophication with special regard to nutrient hotspots that are likely to occur within the rewetted fens.


Subject(s)
Conservation of Natural Resources , Eutrophication , Wetlands , Ecosystem , Groundwater/chemistry , Hydrology , Models, Theoretical , Prospective Studies , Rivers/chemistry
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