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1.
Plants (Basel) ; 13(9)2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38732427

ABSTRACT

The estimation of crop evapotranspiration (ETc) is crucial for irrigation water management, especially in arid regions. This can be particularly relevant in the Po Valley (Italy), where arable lands suffer from drought damages on an annual basis, causing drastic crop yield losses. This study presents a novel approach for vegetation-based estimation of crop evapotranspiration (ETc) for maize. Three years of high-resolution multispectral satellite (Sentinel-2)-based Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), Normalized Difference Red Edge Index (NDRE), and Leaf Area Index (LAI) time series data were used to derive crop coefficients of maize in nine plots at the Acqua Campus experimental farm of Irrigation Consortium for the Emilia Romagna Canal (CER), Italy. Since certain vegetation indices (VIs) (such as NDVI) have an exponential nature compared to the other indices, both linear and power regression models were evaluated to estimate the crop coefficient (Kc). In the context of linear regression, the correlations between Food and Agriculture Organization (FAO)-based Kc and NDWI, NDRE, NDVI, and LAI-based Kc were 0.833, 0.870, 0.886, and 0.771, respectively. Strong correlation values in the case of power regression (NDWI: 0.876, NDRE: 0.872, NDVI: 0.888, LAI: 0.746) indicated an alternative approach to provide crop coefficients for the vegetation period. The VI-based ETc values were calculated using reference evapotranspiration (ET0) and VI-based Kc. The weather station data of CER were used to calculate ET0 based on Penman-Monteith estimation. Out of the Vis, NDWI and NDVI-based ETc performed the best both in the cases of linear (NDWI RMSE: 0.43 ± 0.12; NDVI RMSE: 0.43 ± 0.095) and power (NDWI RMSE: 0.44 ± 0.116; NDVI RMSE: 0.44 ± 0.103) approaches. The findings affirm the efficacy of the developed methodology in accurately assessing the evapotranspiration rate. Consequently, it offers a more refined temporal estimation of water requirements for maize cultivation in the region.

2.
Heliyon ; 10(1): e23238, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38163152

ABSTRACT

Microalgae cultivation could contribute to the achievement of several sustainable development goals (SDGs). However, cultivating Chlorella vulgaris, like any other microalgae, is challenging due to various biotic, abiotic and process related factors that can affect its growth and biomass productivity. Nutrient availability, particularly N and P, and their ratio play a crucial role in building cellular structures and maintaining metabolic processes, determining basically the maximum achievable biomass productivity under given circumstances. The present article aims to improve the N and P ratio to enhance the biomass productivity of Chlorella vulgaris microalgae as well as to characterize the biomass growth kinetics that can be used for prediction purposes. The results showed that the nutrient solutions prepared with increased nitrate concentration (T1 - N:P = 55:1 and T3 - N:P = 28:1) promoted chlorophyll formation and significantly outperformed the control sample (BG-11 - N:P = 35:1) with 192% and 183%, leading to higher biomass productivity with 1160 µg L-1 and 1103 µg L-1, respectively. Moreover, a strong positive correlation was revealed (0.81) between phosphate concentration and microalgae activity rate, indicating the role of phosphorous in energy transfer, resulted in stimulated microalgae activity rates with 71.2% and 70.66% in the phosphate-increased nutrient solutions (T2 - N:P = 14:1 and T3 - N:P = 28:1). In addition, an exponential equation was introduced to characterize the biomass growth kinetics, of which the theoretically achievable maximum chlorophyll concentration (CTAM) and the theoretical cultivation time (tcultivation) were determined for the tested nutrient solutions with variable N:P ratio. It was concluded, that the higher the N:P ratio, the higher the CTAM is, nevertheless the absolute concentration of these nutrients need to be considered as well. The introduced two key parameters could provide valuable information for decision makers regarding the optimization of growth conditions, nutrient supplementation, and harvesting, additionally decreasing the production costs and making the cultivation cycles more effective and sustainable.

3.
Int J Phytoremediation ; 25(11): 1510-1523, 2023.
Article in English | MEDLINE | ID: mdl-36734108

ABSTRACT

In phytostabilization, heavy metal-tolerant plants (e.g.,grasses) can be used to reduce the mobility of heavy metals in soils. The most important step in phytostabilization is the selection of the suitable plant species, in which growth and development can be supported by soil amendments. Sewage sludge compost could be a suitable additive, which provides nutrients for the plant species used for phytostabilization and contributes to an alternative solution for sewage sludge utilization. The aim of the study was to examine the potential of sewage sludge compost in phytostabilization for heavy metal contaminated matrices: identify the optimal ratio of sewage sludge compost to decrease phytotoxicity of the matrices, and assessment of feasible plant species for phytostabilization based on its bioaccumulation properties. In this research, perennial ryegrass (Lolium perenne), broad-leaved sorrel sorrel (Rumex acetosa), lettuce (Lactuca sativa) and cabbage (Brassica oleracea var. capitata) were used for phytotoxicity experiments as well as for testing sewage sludge compost amended phytostabilization of polluted flotation sludge and mine tailings. Sewage sludge compost increased the pH and electric conductivity of the matrices. High salt content and low acidity, altogether with heavy metals caused harmful physiological effects on plant species grown without any compost addition. In the root development test, as in the germination test, the application of 5% sewage sludge compost proved to be optimal. The lower translocation factors of broad-leaved sorrel and perennial ryegrass showed a higher rate of heavy metal accumulation in the roots. Perennial ryegrass, cabbage, and lettuce plant species reached their maximum biomass by adding 5% of sewage sludge compost. Based on the bioaccumulation, translocation and biomass properties, application of perennial ryegrass is recommended for phytostabilization of heavy metal contaminated sites. Furthermore, composted sewage sludge also had a significant effect on the reduction of heavy metal uptake by cabbage and lettuce, which highlights their role as indicator plants in ecotoxicological measurements.


The effects of sewage sludge compost added to the heavy metals contaminated flotation sludge and mine tailings (pH = 4.8) were examined. The applicability of broad-leaved sorrel and perennial ryegrass that can be found under natural conditions in the study area was assessed as a function of sewage sludge compost ratio for phytostabilization purposes. Moreover, ecotoxicological tests had been performed with cabbage and lettuce on sewage sludge compost + flotation sludge and mine tailings mixtures. Based on the results, it was proved that the phytostabilization is feasible with the investigated plant species by adding 5% of sewage sludge compost to the flotation sludge and mine tailings.


Subject(s)
Composting , Lolium , Metals, Heavy , Soil Pollutants , Sewage/chemistry , Soil , Soil Pollutants/analysis , Biodegradation, Environmental , Plants
4.
Water Sci Technol ; 81(7): 1507-1517, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32616702

ABSTRACT

The main point of this research is to assess the applicability of condensed molasses soluble (CMS), which is an organic by-product of lysine fermentation, as an environmentally friendly complexing agent in rhizofiltration of heavy metal contaminated acid mine drainage (AMD). First, the ecotoxicological properties (growth inhibition, seed germination) of CMS were examined with often applied indicator plant species such as duckweed (Lemna minor) and lettuce (Lactuca sativa) so as to define the possible applicable CMS concentration. Then the heavy metal accumulation and translocation properties of root accumulator plant species, i.e. common reed (Phragmites australis) and sedge (Carex flacca), were studied to optimize CMS concentration for rhizofiltration. Due to the CMS application, significant increase in bioaccumulation was detected in the case of every examined heavy metal (As, Cd, Cu, Pb and Zn) at the end of the experiment. Results also showed that CMS increased the heavy metal concentration in shoots, but did not affect the root accumulation characteristics of the plants. Furthermore, CMS treated plants accumulated heavy metals at higher rates in their roots compared to control. The results suggest that CMS is a viable additive and a complexing agent to aid rhizofiltration of heavy metal contaminated AMD.


Subject(s)
Metals, Heavy/analysis , Soil Pollutants/analysis , Biodegradation, Environmental , Fermentation , Lysine , Mining , Plant Roots
5.
Waste Manag ; 36: 213-21, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25464944

ABSTRACT

Municipal waste landfills represent not only a source of landfill gases, but a source of thermal energy as well. The heat in landfills is generated by physical, chemical and microbiological processes. The goal of our study was to characterize the thermal properties of municipal solid waste (MSW) samples of the given landfill. A new apparatus was designed and constructed to measure heat flow. A systematic test series of 17 discrete measurements was carried out with municipal waste samples of 1.0-1.7 m(3). The thermal conductivity, heat diffusivity and specific heat capacity of the samples were determined. Analysing the results of the sampling and our experiments it was realized that the theoretical fundaments should be clarified. Two theories were developed for the serial and for the parallel heat flow in three phase disperse systems. The serial and parallel models resulted in different theoretical estimations. The measured thermal conductivity and heat diffusivity were better characterized by the parallel heat flow estimations. The results show that heat can flow parallel in solid, liquid and gas phases. Characterization of thermal properties serves to establish the fundament of heat extraction from municipal waste landfills.


Subject(s)
Refuse Disposal/methods , Solid Waste/analysis , Waste Disposal Facilities , Hot Temperature , Models, Theoretical
6.
Ideggyogy Sz ; 60(1-2): 46-50, 2007 Jan 20.
Article in Hungarian | MEDLINE | ID: mdl-17432094

ABSTRACT

Two cases of uncommon manifestation of central nervous system sarcoidosis are reported. A 42 year-old man had a spinal cord sarcoidosis. MRI of the spinal cord showed myelopathy in the cervico-thoracic region, and the T2-weighted image showed increasing signal intensity. Neurological symptoms did not correlate with radiological abnormalities. Neurological manifestation was paucisymptomatic. Half a year later steroid and azathioprine therapy led to almost complete radiological and clinical regression. In the second case we present a 49 year-old woman who had left side internuclear ophthalmoplegia and the brainstem lesion. The patient was proven to have sarcoidosis. In this case no abnormalities were found in brain MRI. Neurological symptoms could not be detected by MRI, probably caused by brainstem parenchymal lesions consisting of microgranulomatosis that is sarcoid "brainstem encephalitis". Neurological symptoms improved after steroid treatment in this case too. In both of the cases pulmonary lymphadenopathy helped to diagnose sarcoidosis. In our cases there were interesting correlations between neurological symptoms and MRI abnormalities. At the spinal cord sarcoidosis the radiological abnormalities were more striking than the clinical manifestation. In the other case we found distinct brainstem symptoms but could not detect MRI abnormalities.


Subject(s)
Central Nervous System Diseases/diagnosis , Sarcoidosis/diagnosis , Adrenal Cortex Hormones/therapeutic use , Adult , Azathioprine/therapeutic use , Central Nervous System Diseases/blood , Central Nervous System Diseases/drug therapy , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Sarcoidosis/blood , Sarcoidosis/drug therapy , Tomography, X-Ray Computed
7.
Orv Hetil ; 147(52): 2493-500, 2006 Dec 31.
Article in Hungarian | MEDLINE | ID: mdl-17294573

ABSTRACT

UNLABELLED: Authors presented data of treatment results and course of disease in 487 ovarian cancer patients treated by primary surgery and paclitaxel-carboplatin combination chemotherapy between July 1, 2002 and December 31, 2003. PATIENTS: Most of our patients (87.8%) belonged to the age-group between 40-70 years. Distribution of their histological diagnosis was as 69.6% serous, 10.7% mucinous, 5.1% endometrial and 4.7% undifferentiated carcinoma. The grade distribution was found as 8.4% grade 1, 40.9% grade 2 and 35.9% grade 3. RESULTS: The primary surgery was evaluated as optimal in 41.7%, suboptimal in 37.3% and exploration was performed in 21.1%. Most patients started chemotherapy 20 days after surgery and 74.2% of them got six courses. During the evaluation period 61 intervallum laparotomies were performed, and resulted on 55.7% optimal debulking. Complete remission was found in 58.9%, and partial remission in 14.7% of patients. This treatment resulted on a complete remission in 40.9% at the follow-up of 12 months.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma/therapy , Ovarian Neoplasms/therapy , Ovariectomy , Adenocarcinoma, Mucinous/therapy , Adult , Aged , Brenner Tumor/therapy , Carboplatin/administration & dosage , Carcinoma/drug therapy , Carcinoma/epidemiology , Carcinoma/pathology , Carcinoma/surgery , Carcinoma, Endometrioid/therapy , Chemotherapy, Adjuvant , Cystadenocarcinoma, Serous/therapy , Drug Administration Schedule , Female , Humans , Hungary/epidemiology , Middle Aged , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/epidemiology , Ovarian Neoplasms/pathology , Ovarian Neoplasms/surgery , Paclitaxel/administration & dosage , Retrospective Studies , Treatment Outcome
8.
Magy Onkol ; 48(4): 275-80, 2004.
Article in Hungarian | MEDLINE | ID: mdl-15655571

ABSTRACT

Data on the first-line treatment of ovarian cancer in special centers of Hungary 2002 and 2003 are presented, involving 283 and 416 patients, respectively. Patients' age, clinical stage and histological type of the tumor were highly similar to literature data, while grades were different. Surgical effectiveness in case of IIIc staged tumors with >1 cm residual mass was 37%. The ratio of interval laparotomy was about 15%. Overall response rates of the first-line treatment of ovarian cancer was 82%, while the rate of complete remissions was 60%. The authors provide detailed analysis of factors that can improve the chemotherapy of ovarian cancer in Hungary.


Subject(s)
Antineoplastic Agents/therapeutic use , Ovarian Neoplasms/drug therapy , Adolescent , Adult , Aged , Aged, 80 and over , Antibiotics, Antineoplastic/administration & dosage , Antineoplastic Agents, Phytogenic/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cancer Care Facilities/statistics & numerical data , Docetaxel , Doxorubicin/administration & dosage , Female , Humans , Hungary , Middle Aged , Neoplasm Staging , Ovarian Neoplasms/pathology , Ovarian Neoplasms/surgery , Ovariectomy , Paclitaxel/administration & dosage , Retrospective Studies , Taxoids/administration & dosage , Topotecan/administration & dosage , Treatment Outcome
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