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1.
J Environ Manage ; 344: 118372, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37343474

RESUMO

Alternate wet and dry (AWD) irrigation and organic fertilizers substitution (OFS) have contrasting effects on CH4 and N2O emissions in rice cultivation. Combining these two practices may be feasible for simultaneous reduction of CH4 and N2O emission from paddy. Hence, we conducted a two-year field experiment to explore the reduction of greenhouse gases under the combination of AWD and OFS. The field experiment which was designed with two irrigation methods (continuous flooding (CF) irrigation and AWD irrigation), and five nitrogen regimes (N0, N135, and N180 represent 0, 135, and 180 kg N ha-1, respectively, ON25 and ON50 represent 25% and 50% OFS for inorganic fertilizer, respectively). The results showed a single-peak emission for CH4 fluxes during the whole rice growing season in all water and nitrogen treatments while the N2O fluxes peak only observed during tillering period with AWD irrigation. AWD irrigation and OFS showed a limited reduction in global warming potential (GWP). These were owing to that AWD irrigation reduced 38.3% CH4 emissions while increase 145.9% N2O emissions when compared to CF irrigation, and the low rate (25%) OFS only reduced CH4 emission by 29.4% while high rate (50%) only reduce N2O emission by 38.8% when compared to conventional inorganic nitrogen fertilizer (N180). Combined AWD and ON25 could maximize the reduction in GWP and yield-scaled GWP, which were reduce 58.0% and 52.5%, respectively, compare to the conventional water and nitrogen management (CF and N180). Furthermore, the structural equation modelling (SEM) indicated that the soil dissolved organic carbon (DOC) and rice aboveground biomass showed a significant positive effect on CH4 fluxes while soil NH4+ with a negative effect, and the soil NH4+, nitrification potential, denitrification potential significant affected N2O fluxes with a positive effect while DOC with a negative effect. These results investigated that 25% OFS rate for inorganic fertilizer could further reduce warming potential in AWD irrigation rice field.


Assuntos
Gases de Efeito Estufa , Oryza , Gases de Efeito Estufa/análise , Fertilizantes/análise , Metano/análise , Óxido Nitroso/análise , Solo/química , Nitrogênio/análise , Água , Agricultura/métodos , China
2.
Environ Geochem Health ; 45(11): 8135-8151, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37548848

RESUMO

Rice is a global dietary staple and its traditional cultivation under flooded soil conditions leads to accumulation of arsenic (As) in rice grains. Alternate wetting and drying (AWD) is a widely advocated water management practice to achieve lower As concentrations in rice, water savings, and decreased methane emissions. It is not yet clear whether AWD leads to tradeoffs between concentrations of As and micronutrient elements (e.g., zinc, manganese, molybdenum) in rice grain. We analyzed pore water chemistry and rice grain composition data from a field experiment conducted in Arkansas, USA, in 2017 and 2018 to test the hypothesis that AWD will have diverging effects on oxyanion-forming (arsenic, molybdenum) vs. cationic (cadmium, zinc, manganese, copper) trace elements. This was hypothesized to occur via decreases in soil pH and/or precipitation of iron oxide minerals during oxidizing conditions under AWD. Solubility of all trace elements, except zinc, increased in more reducing conditions. Consistent with our hypothesis, AWD tended to increase grain concentrations of cationic elements while decreasing grain concentrations of oxyanionic elements. Decreases in total As in rice grains under AWD were mainly driven by changes in dimethylarsinic concentrations, with negligible changes in inorganic As. Linear mixed-effects modeling showed that effects of AWD on grain composition were more significant in 2017 compared to 2018. These differences may be related to the timing of dry-downs in the developmental stage of rice plants, with dry-downs during the heading stage of rice development leading to larger impacts on grain composition of certain elements. We also observed significant interannual variability in grain elemental composition from continuously-flooded fields and postulate the warmer temperatures in 2018 may have played a role in these differences.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Oligoelementos , Solo/química , Arsênio/análise , Cádmio/análise , Oryza/química , Manganês , Micronutrientes , Molibdênio , Zinco , Água , Poluentes do Solo/análise
3.
Sensors (Basel) ; 22(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35161531

RESUMO

This study aims to design, develop, and evaluate the traction performance of an electric all-wheel-drive (AWD) tractor based on the power transmission and electric systems. The power transmission system includes the electric motor, helical gear reducer, planetary gear reducer, and tires. The electric system consists of a battery pack and charging system. An engine-generator and charger are installed to supply electric energy in emergency situations. The load measurement system consists of analog (current) and digital (battery voltage and rotational speed of the electric motor) components using a controller area network (CAN) bus. A traction test of the electric AWD tractor was performed towing a test vehicle. The output torques of the tractor motors during the traction test were calculated using the current and torque curves provided by the motor manufacturer. The agricultural work performance is verified by comparing the torque and rpm (T-N) curve of the motor with the reduction ratio applied. The traction is calculated using torque and specifications of the wheel, and traction performance is evaluated using tractive efficiency (TE) and dynamic ratio (DR). The results suggest a direction for the improvement of the electric drive system in agricultural research by comparison with the conventional tractor through the analysis of the agricultural performance and traction performance of the electric AWD tractor.


Assuntos
Agricultura , Tração , Fontes de Energia Elétrica , Eletricidade , Torque
4.
Sensors (Basel) ; 22(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35632045

RESUMO

Rice irrigation by continuous flooding is highly water demanding in comparison with most methods applied in the irrigation of other crops, due to a significant deep percolation and surface drainage of paddies. The pollution of water resources and methane emissions are other environmental problems of rice agroecosystems, which require effective agronomic changes to safeguard its sustainable production. To contribute to this solution, an experimental study of alternate wetting and drying flooding (AWD) was carried out in the Center of Portugal in farmer's paddies, using the methodology of field irrigation evaluation. The AWD results showed that there is a relevant potential to save about 10% of irrigation water with a reduced yield impact, allowing an additional period of about 10 to 29 days of dry soil. The guidelines to promote the on-farm scale AWD automation were outlined, integrating multiple data sources, to get a safe control of soil water and crop productivity. The conclusions point out the advantages of a significant change in the irrigation procedures, the use of water level sensors to assess the right irrigation scheduling to manage the soil deficit and the mild crop stress during the dry periods, and the development of paddy irrigation supplies, to allow a safe and smart AWD.


Assuntos
Oryza , Dessecação , Portugal , Solo , Água
5.
Sensors (Basel) ; 21(18)2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34577246

RESUMO

Water, one of the most valuable resources, is underutilized in irrigated rice production. The yield of rice, a staple food across the world, is highly dependent on having proper irrigation systems. Alternate wetting and drying (AWD) is an effective irrigation method mainly used for irrigated rice production. However, unattended, manual, small-scale, and discrete implementations cannot achieve the maximum benefit of AWD. Automation of large-scale (over 1000 acres) implementation of AWD can be carried out using wide-area wireless sensor network (WSN). An automated AWD system requires three different WSNs: one for water level and environmental monitoring, one for monitoring of the irrigation system, and another for controlling the irrigation system. Integration of these three different WSNs requires proper dimensioning of the AWD edge elements (sensor and actuator nodes) to reduce the deployment cost and make it scalable. Besides field-level monitoring, the integration of external control parameters, such as real-time weather forecasts, plant physiological data, and input from farmers, can further enhance the performance of the automated AWD system. Internet of Things (IoT) can be used to interface the WSNs with external data sources. This research focuses on the dimensioning of the AWD system for the multilayer WSN integration and the required algorithms for the closed loop control of the irrigation system using IoT. Implementation of the AWD for 25,000 acres is shown as a possible use case. Plastic pipes are proposed as the means to transport and control proper distribution of water in the field, which significantly helps to reduce conveyance loss. This system utilizes 250 pumps, grouped into 10 clusters, to ensure equal water distribution amongst the users (field owners) in the wide area. The proposed automation algorithm handles the complexity of maintaining proper water pressure throughout the pipe network, scheduling the pump, and controlling the water outlets. Mathematical models are presented for proper dimensioning of the AWD. A low-power and long-range sensor node is developed due to the lack of cellular data coverage in rural areas, and its functionality is tested using an IoT platform for small-scale field trials.


Assuntos
Internet das Coisas , Oryza , Automação , Dessecação , Água
6.
J Environ Manage ; 297: 113402, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34333312

RESUMO

Inefficient water management in rice paddy is responsible for a large quantity of water and nutrient loss, which causes tremendous economic and environmental costs. Yet, quantified data on the water and nutrient losses are limited. A study was conducted during 2018-2019 with an Aman (wet)-Boro (dry)-Aman (wet) rice rotation to evaluate the effect of water management on water and nutrient losses through different pathways. The treatments in 2018 Aman season were: (i) rainfed, (ii) I6D (irrigation after six days of ponded water disappearance), and (iii) I3D. In 2019, the Boro season had (i) I6D and (ii) I3D, and the Aman season had (i) rainfed, (ii) I9D, and (iii) I1D treatments. The water input and output from the studied lysimeters were measured daily, and samples from the leachates, ponded water, and topsoil were routinely analyzed for nutrient content. In both Aman seasons, the rainfed cultivation had lower percolation losses (38-44 % of total input) than other treatments (45-70 %). Evapotranspiration in the Boro season (5.4-5.9 mm/day) was higher than that in the Aman seasons (4.2-4.6 mm/day) because of the drier Boro season. Ammonium (NH4⁺-N) leached at 0.6-6.7 mg/L and nitrate (NO3⁻-N) 0.6-5.6 mg/L in these rice seasons. Phosphorus concentration ranged 0.04-0.37 mg/L in the leachates and 0.04-0.51 mg/L in the ponded water. The rainfed and I9D exerted higher nutrient leaching concentration in some events and less so for the I6D treatment than the I3D and I1D, possibly because of the better nitrification and preferential flow paths induced by the prolonged drying processes. However, the rainfed, I9D, and I6D had less leaching load than the I3D and I1D because the latter had larger percolation volume. For example, the I6D treatment in the Boro season reduced the N leaching load by 44 % and P load by 39 % compared with the I3D, and the I9D in 2019 Aman season had 42 and 13 % less N and P leaching load, respectively, than the I1D treatment. The findings will contribute to the effort of developing a sustainable and climate-resilient rice production system.


Assuntos
Oryza , Agricultura , Fertilizantes , Nitrogênio/análise , Nutrientes , Fósforo , Solo , Água
7.
Int J Mol Sci ; 21(19)2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33019537

RESUMO

Awd, the Drosophila homologue of NME1/2 metastasis suppressors, plays key roles in many signaling pathways. Mosaic analysis of the null awdJ2A4 allele showed that loss of awd gene function blocks Notch signaling and the expression of its target genes including the Wingless (Wg/Wnt1) morphogen. We also showed that RNA interference (RNAi)-mediated awd silencing (awdi) in larval wing disc leads to chromosomal instability (CIN) and to Jun amino-terminal kinases (JNK)-mediated cell death. Here we show that this cell death is independent of p53 activity. Based on our previous finding showing that forced survival of awdi-CIN cells leads to aneuploidy without the hyperproliferative effect, we investigated the Wg expression in awdi wing disc cells. Interestingly, the Wg protein is expressed in its correct dorso-ventral domain but shows an altered cellular distribution which impairs its signaling. Further, we show that RNAi-mediated knock down of awd in wing discs does not affect Notch signaling. Thus, our analysis of the hypomorphic phenotype arising from awd downregulation uncovers a dose-dependent effect of Awd in Notch and Wg signaling.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Regulação da Expressão Gênica no Desenvolvimento , Nucleosídeo NM23 Difosfato Quinases/genética , Núcleosídeo-Difosfato Quinase/genética , Asas de Animais/metabolismo , Via de Sinalização Wnt/genética , Proteína Wnt1/genética , Animais , Morte Celular , Instabilidade Cromossômica , Cromossomos de Insetos/química , Cromossomos de Insetos/metabolismo , Proteínas de Drosophila/antagonistas & inibidores , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/citologia , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Larva/citologia , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , Masculino , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Núcleosídeo-Difosfato Quinase/antagonistas & inibidores , Núcleosídeo-Difosfato Quinase/metabolismo , Fenótipo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Asas de Animais/citologia , Asas de Animais/crescimento & desenvolvimento , Proteína Wnt1/metabolismo
8.
Contact Dermatitis ; 77(1): 25-34, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28300294

RESUMO

BACKGROUND: Many skin diseases are associated with either increases or decreases in lamellar body secretion, or dysfunctional lamellar bodies. Consequently, diseased skin is characterized by reduced barrier function and altered lipid composition and organization. Human skin is commonly evaluated in vivo with non-invasive biophysical techniques. The dynamic functions of the skin are evaluated with repeat measurements such as the sorption-desorption test (SDT). OBJECTIVES: The aim of this study was to evaluate in vivo skin hydration-dehydration kinetics after treatment with a lipid system that mimics the morphology, structure and composition of lamellar bodies in both healthy and irritated human skin. METHODS: A patch with an aqueous solution of 2% sodium lauryl sulfate (SLS) was used to irritate the skin of the volunteers. The SDT was performed with the CM 820 corneometer. RESULTS: After treatment with this system, both healthy and SLS-irritated skin increased their ability to retain water and to release water slowly during the desorption phase. CONCLUSIONS: Treatment with this system seems to reinforce the barrier function in both healthy and SLS-irritated human skin. Therefore, the present study provides evidence that this system could be of interest for developing future treatments for protecting and repairing the skin.


Assuntos
Dermatite Irritante/diagnóstico , Absorção Cutânea , Testes Cutâneos/métodos , Água/metabolismo , Adulto , Epiderme/metabolismo , Feminino , Humanos , Irritantes/administração & dosagem , Metabolismo dos Lipídeos , Pessoa de Meia-Idade , Fenômenos Fisiológicos da Pele
9.
Environ Pollut ; 347: 123786, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484962

RESUMO

Water management in paddy soils can effectively reduce the soil-to-rice grain transfer of either As or Cd, but not of both elements simultaneously due to the higher mobility of As under reducing and Cd under oxidizing soil conditions. Limestone amendment, the common form of liming, is well known for decreasing Cd accumulation in rice grown on acidic soils. Sulfate amendment was suggested to effectively decrease As accumulation in rice, especially under intermittent soil flooding. To study the unknown effects of combined sulfate and limestone amendment under intermittent flooding for simultaneously decreasing As and Cd in rice, we performed a pot experiment using an acidic sandy loam paddy soil. We also included a clay loam paddy soil to study the role of soil texture in low-As rice production under intermittent flooding. We found that liming not only decreased rice Cd concentrations but also greatly decreased dimethylarsenate (DMA) accumulation in rice. We hypothesize that this is due to suppressed sulfate reduction, As methylation, and As thiolation by liming in the sulfate-amended soil and a higher share of deprotonated DMA at higher pH which is taken up less readily than protonated DMA. Decreased gene abundance of potential soil sulfate-reducers by liming further supported our hypothesis. Combined sulfate and limestone amendment to the acidic sandy loam soil produced rice with 43% lower inorganic As, 72% lower DMA, and 68% lower Cd compared to the control soil without amendment. A tradeoff between soil aeration and water availability was observed for the clay loam soil, suggesting difficulties to decrease As in rice while avoiding plant water stress under intermittent flooding in fine-textured soils. Our results suggest that combining sulfate amendment, liming, and intermittent flooding can help to secure rice safety when the presence of both As and Cd in coarse-textured soils is of concern.


Assuntos
Arsênio , Compostos de Cálcio , Oryza , Óxidos , Poluentes do Solo , Cádmio/análise , Arsênio/análise , Carbonato de Cálcio , Solo , Sulfatos , Argila , Óxidos de Enxofre , Areia , Poluentes do Solo/análise
10.
J Urol ; 190(3): 850-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23507396

RESUMO

PURPOSE: A phase I trial of intravesical recombinant adenovirus mediated interferon-α2b gene therapy (rAd-IFNα) formulated with the excipient SCH Syn3 was conducted in patients with nonmuscle invasive bladder cancer who had disease recurrence after treatment with bacillus Calmette-Guérin. The primary objective was to determine the safety of rAd-IFNα/Syn3. Secondary end points were demonstrated effective rAd-IFNα gene expression and preliminary evidence of clinical activity at 3 months. MATERIALS AND METHODS: A total of 17 patients with recurrent nonmuscle invasive bladder cancer after bacillus Calmette-Guérin treatment were enrolled in the study. A single treatment of rAd-IFNα (3 × 10(9) to 3 × 10(11) particles per ml) formulated with the excipient Syn3 was administered. Patient safety was evaluated for 12 or more weeks. Efficacy of gene transfer was determined by urine IFNα protein concentrations. Preliminary drug efficacy was determined at 3 months. RESULTS: Intravesical rAd-IFNα/Syn3 was well tolerated as no dose limiting toxicity was encountered. Urgency was the most common adverse event and all cases were grade 1 or 2. rAd-IFNα DNA was not detected in the blood. However, transient low serum IFNα and Syn3 levels were measured. High and prolonged dose related urine IFNα levels were achieved with the initial treatment. Of the 14 patients treated at doses of 10(10) or more particles per ml with detectable urine IFNα, 6 (43%) experienced a complete response at 3 months and 2 remained disease-free at 29.0 and 39.2 months, respectively. CONCLUSIONS: Intravesical rAd-IFNα/Syn3 was well tolerated with no dose limiting toxicity encountered. Dose dependent urinary IFNα concentrations confirmed efficient gene transfer and expression. Intravesical rAd-IFNα/Syn3 demonstrated clinical activity in nonmuscle invasive bladder cancer recurring after bacillus Calmette-Guérin.


Assuntos
Carcinoma de Células de Transição/terapia , Terapia Genética/métodos , Interferon-alfa/administração & dosagem , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/terapia , Neoplasias da Bexiga Urinária/terapia , Adenoviridae/genética , Administração Intravesical , Adulto , Idoso , Idoso de 80 Anos ou mais , Vacina BCG/administração & dosagem , Carcinoma de Células de Transição/mortalidade , Carcinoma de Células de Transição/patologia , Ácidos Cólicos/administração & dosagem , Dissacarídeos/administração & dosagem , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Vetores Genéticos , Humanos , Interferon alfa-2 , Interferon-alfa/genética , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/patologia , Prognóstico , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Medição de Risco , Análise de Sobrevida , Falha de Tratamento , Resultado do Tratamento , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
11.
Environ Pollut ; 310: 119829, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35917836

RESUMO

The natural occurrence of arsenic (As) in groundwater & soils and its bioaccumulation in rice grains is a major health concern worldwide. To combat the problem, best combination of irrigation management and suitable rice variety altering As content in grains must be ensured. With this aim, a field trial was conducted with two rice varieties and water management including alternate wetting and drying (AWD) and continuous flooding (CF) irrigation regimes with As contaminated groundwater (AsW) and temporarily stored groundwater (TSG) and river water for only CF (as control). Results revealed that As content in different portions of paddy plant was significantly different (P < 0.001) with irrigation practices and rice varieties. AWD irrigation with TSG accumulated lower As in rice grains compared with CF-AsW for both varieties. Data showed that AWD-TSG practice led to 61.37% and 60.34% grain As reduction for BRRI dhan28 and BRRI dhan29, respectively, compared with CF-AsW. For Principle Component Analysis (PCA), first principle component (PC1) explained 91.7% of the variability and irrigation water As, soil total and available As, straw As, root As and husk As were the dominating parameters. With significant (P < 0.05) variation in yields between the genotypes, AWD increased grain yield by 29.25% in BRRI dhan29 Compared with CF. However, translocation factor (TF) and bioconcentration factor (BCF) for both varieties were less than one for all the treatments. The addition of this study to our knowledge base is that, AWD-TSG with BRRI dhan29 can be an As-safe practice without compromising yields.


Assuntos
Arsênio , Oryza , Poluentes do Solo , Irrigação Agrícola , Grão Comestível , Solo , Água
12.
Ann Med ; 53(1): 900-907, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34121552

RESUMO

BACKGROUND: Abdominal wound dehiscence (AWD) is a major complication of abdominal surgery, and neonates are a group with a high risk of AWD, which has serious consequences or can even result in death. The purpose of this study is to explore the risk factors for neonatal AWD and construct a predictive model. METHODS: The clinical data of 453 cases that underwent neonatal laparotomy from June 2009 to June 2020 were retrospectively analyzed, among which 27 cases of AWD were identified. Nine factors, including gender, age at admission, weight at admission, preterm delivery, level of preoperative anaemia, hypoalbuminemia, operation time, incision length, and incision type, were analyzed to explore their correlation with neonatal AWD. RESULTS: The incidence of neonatal AWD was 6.0% (27/453), among which partial wound dehiscence accounted for 4.9% (22/453) and complete wound dehiscence accounted for 1.1% (5/453). Hypoproteinemia and incision type were the independent risk factors for neonatal AWD, and weight at admission was a protective factor for AWD in the multivariate models. All these factors were incorporated to construct a nomogram, and a calibration curve was plotted. The result indicated that the actual risk was close to the predicted risk when the predicted risk rate was greater than about 35%. CONCLUSIONS: Neonatal AWD is closely related to hypoproteinemia and incision contamination. Our predictive model showed the potential to provide an individualized risk estimate of AWD for neonatal patients undergoing abdominal surgery.Key messagesNeonatal abdominal wound dehiscence (AWD) has a serious consequence and the incidence of neonatal AWD was about 6.0% and the complete AWD morbidity is 1.1%.Hypoproteinemia and incision type were the independent risk factors for neonatal AWD.Our predictive model showed the potential to provide an individualized risk estimate of AWD for neonatal patients undergoing abdominal surgery.


Assuntos
Hipoproteinemia , Deiscência da Ferida Operatória , Abdome/cirurgia , Humanos , Recém-Nascido , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco , Deiscência da Ferida Operatória/epidemiologia , Deiscência da Ferida Operatória/etiologia
13.
Sci Total Environ ; 698: 134212, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31783470

RESUMO

Rice, one of the major sources of CH4 and N2O emissions, is also the largest consumer of water resources. Mild alternate wetting and drying (AWD) irrigation is widely adopted to save irrigation water resources and maintain rice production, but its effects on CH4 and N2O emissions are unclear. In addition, previous studies have revealed different effects of mid-season drainage on global warming potential (GWP), owing to the different criteria used. In this study, a pot experiment was conducted to investigate the effects of mild AWD irrigation and mid-season drainage (a specific soil moisture) on CH4 and N2O emissions during rice cultivation. Four water management systems were applied: AWD + D0 (mild AWD irrigation without mid-season drainage), AWD + D1 (mild AWD irrigation with mid-season drainage), CF + D0 (continuous flooding without mid-season drainage) and CF + D1 (continuous flooding with mid-season drainage); nitrogen was applied at two levels (N90 and N180) along with each treatment. The results showed that mild AWD irrigation reduced CH4 cumulative emissions by an average of 87.1% but increased N2O cumulative emissions by an average of 280% compared to the values observed with CF irrigation. Mid-season drainage did not affect N2O emissions but interrupted CH4 fluxes and significantly reduced CH4 cumulative emissions. CH4 and N2O cumulative emissions were reduced by an average of 25.0% and 54.2%, respectively, with N90 application compared to values observed with N180 application. Unexpectedly, mild AWD irrigation did not reduce GWP and yield-scaled GWP unlike CF irrigation because a high N2O emission peak occurred during mild AWD irrigation. Furthermore, we observed an obvious trade-off between CH4 and N2O. We suggest that maintaining flooding during nitrogen application but applying mild AWD irrigation for the remaining period may be helpful in reducing CH4 and N2O emissions and GWP.


Assuntos
Agricultura/métodos , Poluentes Atmosféricos/análise , Metano/análise , Dióxido de Nitrogênio/análise , Oryza
14.
Environ Sci Pollut Res Int ; 27(14): 16731-16744, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32133608

RESUMO

Long-term underground exploitation of Zn-Pb ores has led to drainage of the area and formation of a huge dumping ground in the form of a pile. In its vicinity, processes of acid drainage have developed as a result of contamination of soils and groundwater. Geochemical transformations of mineral contents of waste can significantly affect physical and chemical properties of the soils and the bedrock. At the prospect of termination of the mining activity in the near future, determining the routes of the pollution migration, ability to monitor acid drainage processes and assessment of the risk of heavy metal pollution are really crucial. The paper presents a proposal for solving this problem by means of geophysical methods: Electrical Resistivity Tomography (ERT), Time Domain-Induced Polarisation (TDIP), Frequency Domain Electromagnetics (FDEM) and shallow-depth magnetometric surveys combined with geochemical investigations. The obtained results of geophysical surveys have been confirmed by geochemical investigations. The applied ERT and TDIP methods make it possible to identify the spread of the zones of pollution around the tailing pile, but their effectiveness depends on humidity of the ground. Soil magnetometry and shallow-depth induction profiling are a good tool to identify the medium contaminated with minerals redeposited by aeolian processes and allow to determine the range of the dust spread from the pile. It has been shown that the range of impact of the geochemical changes around the tailing pile is high and depends not only on directions and dynamics of water flow from the pile but also on aeolian transport.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , Monitoramento Ambiental , Chumbo , Mineração , Polônia , Zinco/análise
15.
Sci Total Environ ; 653: 1343-1353, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-30759574

RESUMO

Alternate wetting and drying (AWD), has gained increasing attention as a promising strategy for mitigating greenhouse gas emissions (GHG) in flooded rice systems. AWD involves periodic drainage of rice paddies in order to inhibit methane (CH4) emissions. To date, studies evaluating this practice have been limited in their scope and resolution. Our study evaluates the mitigation potential of AWD from a life cycle perspective using high-resolution CH4 modeling to more accurately estimate the mitigation potential of this practice. We simulated California rice production under continuous flooding and under five AWD schedules ranging in the severity and frequency of dry-downs. Production models were coupled with the Peatland Ecosystem Photosynthesis Respiration and Methane Transport (PEPRMT) model to simulate CH4 fluxes at daily intervals. We then evaluated the GHG mitigation potential of AWD using life cycle assessment models. Frequent or severe dry-downs reduced simulated grain yields, which negated some of the benefits of AWD when assessed on a yield-scaled basis. We also found AWD-induced mitigation of CH4 emissions modeled with PEPRMT to be roughly half the magnitude reported from up-scaling of chamber measurements, highlighting the importance of high resolution field data to better characterize GHGs in rice systems. Reduced yields and conservative CH4 mitigation in our model lessened the overall mitigation potential of AWD. When the entire rice life cycle was considered, mitigation of overall global warming potential (GWP) was further reduced by the presence of additional GHG sources, which comprised roughly half of life cycle GWP. Our simulations resulted in ≤12% reductions in GWP kg-1 across all AWD scenarios and saw an increase in GWP when yields were severely reduced. Our results highlight the importance of constraining uncertainties in CH4 emissions and considering a life cycle perspective expressed on a yield-scaled basis in characterizing the mitigation potential of AWD.


Assuntos
Gases de Efeito Estufa/análise , Metano/análise , Agricultura/métodos , Monitoramento Ambiental , Poluição Ambiental/análise , Aquecimento Global , Gases de Efeito Estufa/química , Metano/química , Modelos Teóricos , Oryza
16.
Front Physiol ; 10: 983, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31427986

RESUMO

The Awd (abnormal wing discs) gene is the Drosophila homolog of human NME1 and NME2 metastasis suppressor genes. These genes play a key role in tumor progression. Extensive studies revealed that intracellular NME1/2 protein levels could be related to either favorable or poor prognosis depending on tissue context. More recently, extracellular activities of NME1/2 proteins have also been reported, including a tumor- promoting function. We used Drosophila as a genetic model to investigate the mechanism controlling intra- and extracellular levels of NME1/2. We examined the role of several components of the ESCRT (endosomal sorting complex required for transport) complex in controlling Awd trafficking. We show that the Vps28 component of the ESCRT-I complex is required for maintenance of normal intracellular level of Awd in larval adipocytes. We already showed that blocking of Shibire (Shi)/Dynamin function strongly- lowers Awd intracellular level. To further investigate this down regulative effect, we analyzed the distribution of endosomal markers in wild type and Shi-defective adipocytes. Our results suggest that Awd does not enter CD63-positive endosomes. Interestingly, we found that in fat body cells, Awd partly- colocalizes with the ESCRT accessory component ALiX, the ALG-2 (apoptosis-linked gene 2)-interacting protein X. Moreover, we show that the intracellular levels of both proteins are downregulated by blocking the function of the Dynamin encoded by the shibire gene.

17.
J Bone Oncol ; 19: 100267, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31788417

RESUMO

INTRODUCTION: Clear cell chondrosarcoma (CCC) is a rare subtype of chondrosarcoma and it is commonly considered a low-grade tumor and less aggressive than atypical cartilaginous tumor (grade 1 central chondrosarcoma). However, the experience even of musculoskeletal tumor centres with this rare entity is limited. The aim of this study is to analyse our own treatment results and those of the literature regarding the therapy and outcome of this lesion. MATERIAL AND METHODS: 7 cases of CCC have been treated in our department between 2003 and 2015. Their follow-up data were collected retrospectively. 187 literature cases with histopathological and clinical characteristics were retrieved by means of a PubMed search with the key word "clear cell chondrosarcoma". The data pertaining to treatment and follow up were extracted. We analysed the survival of patient and the risk factors for local recurrence (LR) as well as metastatic disease (MD). RESULTS: The mean age at the time of diagnosis was 40 years. Two thirds of the patients were male. The mean follow-up time was 109 months. To our surprise, there was a high rate of LR (30%) and of MD (20%) when compared to low-grade conventional chondrosarcomas. 15% of LR and 20% of metastatic disease were observed after more than 10 years follow-up. Uncommon locations of MD such as in the spine is a unique observation in chondrosarcomas and underlines the high aggressiveness of this tumor. 10-year overall survival was almost 80%, 10-years disease free survival 60%. Positive margins (p = 0.038) and metastases (p = 0.006) impaired the overall survival significantly. The rate of local recurrence was significantly dependent on resection margin (p < 0.001); however there was no correlation with the grade of differentiation of the tumor. The development of MD was affected by local recurrence (p = 0.006), but we could not detect a significant association with margin status (p = 0.184). CONCLUSIONS: A wide resection is the advocated treatment option. Long term follow-up for at least 10 years is necessary in order to not overlook late LR or MD. This work demonstrates for the first time the apparent aggressiveness of the CCC.

18.
G3 (Bethesda) ; 8(7): 2319-2332, 2018 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-29743189

RESUMO

Developing rice varieties adapted to alternate wetting and drying water management is crucial for the sustainability of irrigated rice cropping systems. Here we report the first study exploring the feasibility of breeding rice for adaptation to alternate wetting and drying using genomic prediction methods that account for genotype by environment interactions. Two breeding populations (a reference panel of 284 accessions and a progeny population of 97 advanced lines) were evaluated under alternate wetting and drying and continuous flooding management systems. The predictive ability of genomic prediction for response variables (index of relative performance and the slope of the joint regression) and for multi-environment genomic prediction models were compared. For the three traits considered (days to flowering, panicle weight and nitrogen-balance index), significant genotype by environment interactions were observed in both populations. In cross validation, predictive ability for the index was on average lower (0.31) than that of the slope of the joint regression (0.64) whatever the trait considered. Similar results were found for progeny validation. Both cross-validation and progeny validation experiments showed that the performance of multi-environment models predicting unobserved phenotypes of untested entrees was similar to the performance of single environment models with differences in predictive ability ranging from -6-4% depending on the trait and on the statistical model concerned. The predictive ability of multi-environment models predicting unobserved phenotypes of entrees evaluated under both water management systems outperformed single environment models by an average of 30%. Practical implications for breeding rice for adaptation to alternate wetting and drying system are discussed.


Assuntos
Adaptação Biológica , Cruzamento , Interação Gene-Ambiente , Genoma de Planta , Genômica , Genótipo , Oryza/genética , Fenótipo , Algoritmos , Genética Populacional/métodos , Estudo de Associação Genômica Ampla , Genômica/métodos , Modelos Genéticos , Modelos Estatísticos , Reprodutibilidade dos Testes , Seleção Genética
19.
Naunyn Schmiedebergs Arch Pharmacol ; 389(11): 1171-1182, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27449069

RESUMO

Dynamin GTPase (Dyn) plays a critical role in membrane-remodelling events underlying endocytosis. Studies in Drosophila identified a functional interaction between the Dyn homologue, encoded by the shibire (shi) gene, and Abnormal wing discs (Awd), a nucleoside diphosphate kinase (NDPK) that is the homologue of group I Nme human genes. These Drosophila studies showed that awd mutations enhance mutant shi phenotype and thus indicated the existence of a highly specific interaction between these genes. Furthermore, in human cells, it has been shown that Nme proteins promote Dyn activity in different membrane compartments through spatially controlled supply of GTP. Interestingly, Awd and Nme proteins have been detected in the extracellular environment. While no role has been inferred to extracellular Awd, presence of Nme1 in cancer patient serum is an unfavourable prognostic marker. In the present work, we used Drosophila and human cell line models to investigate the shuttling Awd/Nme1 proteins between intracellular and extracellular spaces. By using classic and reverse genetic approaches, we show that downregulation of Shi/Dyn1 activity enhances extracellular Awd/Nme1 in both Drosophila and human colon cell lines. We extended our analyses to colon cancer cell lines and found that knocking down Dyn1, besides to raise Nme1 extracellular amount, downregulates expression of molecular components that play key roles in tumour invasion. Interestingly, in vivo analyses of Drosophila larval adipocytes show that the conditional block of Shi activity greatly reduces intracellular amount of Awd confirming that Shi plays a key role in controlling the balance between intracellular and extracellular Awd.


Assuntos
Neoplasias do Colo/enzimologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/enzimologia , Dinamina I/metabolismo , Dinaminas/metabolismo , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Núcleosídeo-Difosfato Quinase/metabolismo , Adipócitos/enzimologia , Animais , Animais Geneticamente Modificados , Neoplasias do Colo/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Dinamina I/genética , Dinaminas/genética , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genótipo , Células HT29 , Humanos , Larva/enzimologia , Mutação , Nucleosídeo NM23 Difosfato Quinases/genética , Núcleosídeo-Difosfato Quinase/genética , Fenótipo , Interferência de RNA , Transfecção
20.
Sci Total Environ ; 461-462: 528-40, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23756213

RESUMO

Assessing water supply capacity is crucial to meet stakeholders' needs, notably in the Mediterranean region. This region has been identified as a climate change hot spot, and as a region where water demand is continuously increasing due to population growth and the expansion of irrigated areas. The Hérault River catchment (2500 km(2), France) is a typical example and a negative trend in discharge has been observed since the 1960s. In this context, local stakeholders need first to understand the processes controlling the evolution of water resources and demands in the past to latter evaluate future water supply capacity and anticipate the tensions users could be confronted to in the future. A modelling framework is proposed at a 10-day time step to assess whether water resources have been able to meet water demands over the last 50 years. Water supply was evaluated using hydrological modelling and a dam management model. Water demand dynamics were estimated for the domestic and agricultural sectors. A water supply capacity index is computed to assess the extent and the frequency to which water demand has been satisfied at the sub-basin scale. Simulated runoff dynamics were in good agreement with observations over the calibration and validation periods. Domestic water demand has increased considerably since the 1980s and is characterized by a seasonal peak in summer. Agricultural demand has increased in the downstream sub-basins and decreased upstream where irrigated areas have decreased. As a result, although most water demands were satisfied between 1961 and 1980, irrigation requirements in summer have sometimes not been satisfied since the 1980s. This work is the first step toward evaluating possible future changes in water allocation capacity in the catchment, using future climate change, dam management and water use scenarios.


Assuntos
Agricultura/métodos , Mudança Climática , Modelos Teóricos , Rios , Ciclo Hidrológico , Movimentos da Água , Abastecimento de Água , Agricultura/estatística & dados numéricos , Previsões , França , Estações do Ano
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