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1.
MethodsX ; 13: 102905, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39253003

RESUMEN

Floods have an important impact on life and loss of goods. Urban green spaces are crucial to mitigating flood impact. However, their capacity to prevent floods depends on their condition, especially in areas highly affected by human activities such as lawns. Here, we developed a simple method to assess flood regulation using soil penetration resistance as a proxy and tested it on an urban lawn in Vilnius (Lithuania) in winter. We developed an experimental design using an app for collecting data and working with it in a GIS environment. To understand their spatial relations, geostatistical (e.g., semi-variogram model and ordinary kriging mapping) and spatial statistics ((Moran's global autocorrelation index and Cluster and Outlier Analysis (Anselin Local Moran's I)) tools were applied. The preliminary results from the tested method showed that the lawn studied has different capacities to retain floods due to the management practices. Nevertheless, it is essential to be applied in different soil moisture conditions since flood regulation (soil penetration resistance) can be variable throughout the year.•A novel method was developed to estimate flood regulation using soil penetration resistance as a proxy;•An urban lawn was used to test the method and identify areas with low and high capacity for flood regulation;•The method quickly assesses lawn flood retention capacity in different environments.

2.
Plants (Basel) ; 13(15)2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39124267

RESUMEN

The recovery of soil properties and the proper growth of natural tree regeneration are key elements for maintaining forest productivity after selective logging operations. This study was conducted on the soil properties and natural growth of two pioneer seedling species of alder and maple which were on skid trails in the mixed beech forests of northern Iran. To examine the long-term effects, we randomly selected six skid trails, with two replicates established for each of three time periods since last use (10, 20, and 30 years ago). Random plots 4 m × 10 m in size, three plots on each skid trail and six plots on areas without soil compaction (control), were selected. Measurements included the physical and chemical properties of the soil and the growth, and the architectural and qualitative characteristics of the seedlings. The results showed that all the soil properties of the 10- and 20-year-old skid trails were significantly different from the control area (except for the soil moisture in the 20-year-old skid trail). The 30-year-old skid trail showed values of other soil properties which were not significantly different from the control area, except for the amounts of organic matter and soil nitrogen, which was less than the control. The skid trails had a negative effect on all of the growth, qualitative, and architectural indices of seedlings. The characteristics of seedlings were related to soil characteristics and had the highest correlation with the soil penetration resistance (R-value from -0.41 to -0.63 for stem growth, p < 0.05; -0.57 to -0.90 for root growth, p < 0.01; and -0.76 to -0.86 for biomass, p < 0.01). The correlation coefficient between soil penetration resistance and the Dickson quality index of alder and maple seedlings was, respectively, -0.74 and -0.72, p < 0.01. The negative effect of soil compaction on root growth (-27.69% for alder seedlings and -28.08% for maple seedlings) was greater than on stem growth (-24.11% for alder seedlings and -16.27% for maple seedlings). The amount of growth, qualitative, and architectural indices of alder seedlings were higher than that of maple seedlings. Although alder is a better choice as compared to maple seedling in the initial year, the results of our study show that it is recommended to plant both alder and maple on skid trails after logging operations.

3.
Sci Total Environ ; 946: 174463, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38964385

RESUMEN

The increasingly urgent issue of climate change is driving the development of carbon dioxide (CO2) capture and separation technologies in flue gas after combustion. The monolithic adsorbent stands out in practical adsorption applications for its simplified powder compaction process while maintaining the inherent balance between energy consumption for regeneration and selectivity for adsorption. However, optimizing the adsorption capacity and selectivity of CO2 separation materials remains a significant challenge. Herein, we synthesized monolithic polymer networks (N-CMPs) with triphenylamine adsorption sites, acid-base environment tolerance, and precise narrow microchannel pore systems for the selective sieving of CO2 and particulate matter (PM) in flue gas. The inherent continuous covalent bonding of N-CMPs, along with their highly delocalized π-π conjugated porous framework, ensures the stability of the monolithic polymer network's adsorption and separation capabilities under wet and acid-base conditions. Specifically, under the conditions of 1 bar at 273 K, the CO2 adsorption capacity of N-CMP-1 is 3.35 mmol/g. Attributed to the highly polar environment generated by triphenylamine and the inherent high micropore/mesopore ratio, N-CMPs exhibit an excellent ideal adsorbed solution theory (IAST) selectivity for CO2/N2 under simulated flue gas conditions (CO2/N2 = 15:85). Dynamic breakthrough experiments further visualize the high separation efficiency of N-CMPs in practical adsorption applications. Moreover, under acid-base conditions, N-CMPs achieve a capture efficiency exceeding 99.76 % for PM0.3, enabling the selective separation of CO2 and PM in flue gas. In fact, the combined capture of hazardous PM and CO2 from the exhaust gases produced by the combustion of fossil fuels will play a pivotal role in mitigating climate change and environmental issues until low-carbon and alternative energy technologies are widely adopted.

4.
Environ Geochem Health ; 46(9): 329, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39012551

RESUMEN

Tailings dust can negatively affect the surrounding environment and communities because the tailings are vulnerable to wind erosion. In this study, the effects of halides (sodium chloride [NaCl], calcium chloride [CaCl2], and magnesium chloride hexahydrate [MgCl2·6H2O]), and polymer materials (polyacrylamide [PAM], polyvinyl alcohol [PVA], and calcium lignosulfonate [LS]) were investigated for the stabilization of tailings for dust control. Erect milkvetch (Astragalus adsurgens), ryegrass (Lolium perenne L.), and Bermuda grass (Cynodon dactylon) were planted in the tailings and sprayed with chemical dust suppressants. The growth status of the plants and their effects on the mechanical properties of tailings were also studied. The results show that the weight loss of tailings was stabilized by halides and polymers, and decreased with increasing concentration and spraying amount of the solutions. The penetration resistance of tailings stabilized by halides and polymers increased with increasing concentration and spraying amount of the solutions. Among the halides and polymers tested, the use of CaCl2 and PAM resulted in the best control of tailings dust, respectively. CaCl2 solution reduces the adaptability of plants and therefore makes it difficult for grass seeds to germinate normally. PAM solutions are beneficial for the development of herbaceous plants. Among the three herbaceous species, ryegrass exhibited the best degree of development and was more suitable for growth in the tailings. The ryegrass plants planted in the tailings sprayed with PAM grew the best, and the root-soil complex that formed increased the shear strength of the tailings.


Asunto(s)
Polvo , Lolium , Lolium/efectos de los fármacos , Cynodon , Planta del Astrágalo , Cloruro de Calcio , Cloruro de Magnesio/farmacología , Cloruro de Sodio/química , Resinas Acrílicas/química , Residuos Industriales , Polímeros , Poaceae , Lignina/análogos & derivados
5.
Environ Sci Pollut Res Int ; 31(25): 36938-36957, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38758437

RESUMEN

Natural disasters and human demolition create vast amounts of construction and demolition waste (CDW), with a substantial portion being concrete waste. Managing this concrete waste is a daunting challenge for developing countries with limited resources, aiming to mitigate its harmful environmental effects. Therefore, the proposed approach involves using recycled fine aggregates (RFA) instead of fresh fine aggregates (FFA) in concrete, which aligns closely with achieving sustainable environmental objectives. Extensive laboratory tests were conducted to assess the effects of adding RFA to concrete. The influence of 0 to 100% RFA replacement and different curing times was investigated on compressive strength, tensile strength, resistance against chloride ion penetration and chemicals exposure, and quality of aggregates. So, around 30%, 35%, 20%, and 79% reductions in compression strength, tensile strength, modulus of elasticity, and workability were estimated when 100% RFA was used in recycled aggregate concrete (RAC). However, according to results analyses, the performance of RAC is reliable up to 50% of RFA in proposed conditions and mix design. In addition, major environmental impacts such as global warming potential, aquatic eutrophication, and aquatic acidification were reduced by 47%, 40%, and 18%, respectively, for concrete having 50% RFA than concrete having 100% FFA.


Asunto(s)
Materiales de Construcción , Reciclaje , Ambiente , Resistencia a la Tracción
6.
Heliyon ; 10(7): e28625, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38571608

RESUMEN

Rice fallow black gram is grown under the residual moisture situation as a relay crop in heavy texture montmorillonite clay soil under zero till condition. Since the crop is raised during post monsoon season, the crop often experiences terminal stress due to limited water availability and no rainfall. Surface irrigation in montmorillonite clay soil is determent to pulse crop as inundation causes wilting. Therefore, zero tilled rice fallow black gram has to be supplemented with micro irrigation at flowering stage (35 days after sowing) to alleviate moisture stress and to increase the productivity as well. Hence micro farm pond in a corner of one ha field was created to harvest the rain water during monsoon season and the same was utilized to supplement the crop with lifesaving irrigation through mobile sprinkler at flowering stage for the crop grown under conservation agriculture. Soil cracking is also the common phenomena of montmorillonite clay soil where evaporations losses would be more through crack surfaces. The present study was therefore conducted to study the changes in the soil physical properties, crop establishment and productivity in conjunction with mechanized sowing and harvest and supplemental mobile sprinkler irrigation. Sowing of black gram by broadcasting 10 days prior to the manual harvest of rice, manual drawn single row seed drill after the machine harvest of rice and sowing by broadcasting at 4 days prior to machine harvest of rice was experimented separately and in combination with lifesaving irrigation. Results indicated that the number of wheel passes and lifesaving irrigation had a very strong impact on soil penetration resistance and soil moisture. Combined harvester followed by no till seed drill increased the soil penetration resistance in all the layers (0-5 cm, 5-10 cm and 10-15 cm). Two passes of wheel increased the mean soil penetration resistance from 407 KPa to 502 KPa. The soil penetration resistance (0-5 cm) at harvest shown that black gram sown by manual broadcasting 10 days prior to manual harvest of paddy supplemented with life irrigation on 30 DAS reduced the soil penetration resistance from 690 Kpa to 500 Kpa, 740 Kpa to 600 Kpa and 760 Kpa to 620 Kpa respectively at 0-5 cm, 5-10 cm and 10-15 cm layer. In general, moisture depletion rate was rapid in the surface layer of 0-5 cm as compared to other layers of 5-10 cm and 10-15 cm up to 30 DAS (Flowering stage). The moisture content and the soil penetration resistance had an inverse relationship. The soil penetration resistance also had an inverse relationship with the root length in which the root length lowers as the soil penetration resistance increases. The soil crack measured at 60 DAS was deeper with no till seed drill (width of 3.94 cm and depth of 13.67 cm) which was mainly due to surface layer compaction. The relative water content, specific leaf weight and chlorophyll content were significantly improved through the supplemental irrigation given on 30 DAS irrespective of crop establishment methods. The results further indicated that compaction of ploughed layer in the moist soil due to combined harvester and no till seed drill had a negative impact on yield (457 kg ha-1), which was improved by 19.03 per cent due to increased soil moisture with supplemental irrigation. The mean yield increase across different treatments due to supplemental lifesaving irrigation through mobile sprinkler was 20.4 per cent.

7.
Int J Biol Macromol ; 266(Pt 1): 130941, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38521305

RESUMEN

Recent studies revealed that insect chemosensory proteins (CSPs) both play essential roles in insect olfaction and insect resistance. However, functional evidence supporting the crosslink between CSP and insecticide resistance remains unexplored. In the present study, 22 SfruCSP transcripts were identified from the fall armyworm (FAW) and SfruCSP1 and SfruCSP2 are enriched in the larval cuticle and could be induced by multiple insecticides. Both SfruCSP1 and SfruCSP2 are highly expressed in the larval inner endocuticle and outer epicuticle, and these two proteins exhibited high binding affinities with three insecticides (chlorfenapyr, chlorpyrifos and indoxacarb). The knockdown of SfruCSP1 and SfruCSP2 increased the susceptibility of FAW larvae to the above three insecticides, and significantly increased the penetration ratios of these insecticides. Our in vitro and in vivo evidence suggests that SfruCSP1 and SfruCSP2 are insecticide binding proteins and confer FAW larval resistance to chlorfenapyr, chlorpyrifos and indoxacarb by an insecticide sequestration mechanism. The study should aid in the exploration of larval cuticle-enriched CSPs for insect resistance management.


Asunto(s)
Proteínas de Insectos , Resistencia a los Insecticidas , Insecticidas , Larva , Oxazinas , Spodoptera , Animales , Spodoptera/efectos de los fármacos , Spodoptera/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Resistencia a los Insecticidas/genética , Insecticidas/farmacología , Larva/efectos de los fármacos , Cloropirifos/farmacología
8.
Phytopathology ; 114(2): 418-426, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37665321

RESUMEN

Our previous research showed that a powdery mildew resistant barley line (MvHV07-17) maintains its resistance to Blumeria hordei (Bh) even if plants are exposed to a long-term high temperature of 35°C for 120 h before Bh inoculation, whereas such high temperature pretreatment further increases susceptibility to infection in the susceptible barley line MvHV118-17. In the present study, we extended this approach using short-term high-temperature water treatment (49°C for 30 s) to determine how it affects powdery mildew resistance in these barley lines. We found that this short-term heat shock (HS) impaired plant defense responses, as reflected by development of Bh colonies and visible necrotic spots on leaves of MvHV07-17, which does not develop visible symptoms upon Bh inoculation under optimal growth conditions. In contrast, both HS and long-term heat stress enhanced susceptibility to Bh in MvHV118-17 plants. These results were supported by the measurement of Bh biomass using a qPCR method. Furthermore, microscopic examinations showed that HS elevated the rate of successful Bh penetration events and the spread of cell death in the surrounding mesophyll area and allowed for colony formation and sporulation in resistant barley, whereas early and effective plant defense responses, such as papilla formation and single-cell epidermal hypersensitive response, were significantly reduced. Furthermore, we found that the accumulation of hydrogen peroxide in both resistant and susceptible barley was correlated with susceptibility induced by HS and long-term heat-stress. This study may contribute to a better understanding of plant defense responses to Bh in barley exposed to heat. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Asunto(s)
Hordeum , Temperatura , Enfermedades de las Plantas , Biomasa , Muerte Celular , Erysiphe
9.
Int J Biol Macromol ; 254(Pt 1): 127642, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37898258

RESUMEN

Overuse of insecticides has led to severe environmental problems. Insect cuticle, which consists mainly of chitin, proteins and a thin outer lipid layer, serves multiple functions. Its prominent role is as a physical barrier that impedes the penetration of xenobiotics, including insecticides. Blattella germanica (L.) is a major worldwide indoor pest that causes allergic disease and asthma. Extensive use of pyrethroid insecticides, including ß-cypermethrin, has selected for the rapid and independent evolution of resistance in cockroach populations on a global scale. We demonstrated that BgCPLCP1, the first CPLCP (cuticular proteins of low complexity with a highly repetitive proline-rich region) family cuticular protein in order Blattodea, contributes to insecticide penetration resistance. Silencing BgCPLCP1 resulted in 85.0 %-85.7 % and 81.0 %-82.0 % thinner cuticle (and especially thinner endocuticle) in the insecticide-susceptible (S) and ß-cypermethrin-resistant (R) strains, respectively. The thinner and more permeable cuticles resulted in 14.4 % and 20.0 % lower survival of ß-cypermethrin-treated S- and R-strain cockroaches, respectively. This study advances our understanding of cuticular penetration resistance in insects and opens opportunities for the development of new efficiently and environmentally friendly insecticides targeting the CPLCP family of cuticular proteins.


Asunto(s)
Blattellidae , Insecticidas , Piretrinas , Animales , Insecticidas/farmacología , Resistencia a los Insecticidas/genética , Piretrinas/farmacología , Blattellidae/genética , Alérgenos
10.
J Exp Bot ; 75(5): 1465-1478, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-37952108

RESUMEN

Powdery mildew fungi are obligate biotrophic pathogens that only invade plant epidermal cells. There are two epidermal surfaces in every plant leaf: the adaxial (upper) side and the abaxial (lower) side. While both leaf surfaces can be susceptible to adapted powdery mildew fungi in many plant species, there have been observations of leaf abaxial immunity in some plant species including Arabidopsis. The genetic basis of such leaf abaxial immunity remains unknown. In this study, we tested a series of Arabidopsis mutants defective in one or more known defense pathways with the adapted powdery mildew isolate Golovinomyces cichoracearum UCSC1. We found that leaf abaxial immunity was significantly compromised in mutants impaired for both the EDS1/PAD4- and PEN2/PEN3-dependent defenses. Consistently, expression of EDS1-yellow fluorescent protein and PEN2-green fluorescent protein fusions from their respective native promoters in the respective eds1-2 and pen2-1 mutant backgrounds was higher in the abaxial epidermal cells than in the adaxial epidermal cells. Altogether, our results indicate that leaf abaxial immunity against powdery mildew in Arabidopsis is at least partially due to enhanced EDS1/PAD4- and PEN2/PEN3-dependent defenses. Such transcriptionally pre-programmed defense mechanisms may underlie leaf abaxial immunity in other plant species such as hemp and may be exploited for engineering adaxial immunity against powdery mildew fungi in crop plants.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regiones Promotoras Genéticas , Hojas de la Planta/metabolismo , Mecanismos de Defensa , Enfermedades de las Plantas/microbiología
11.
Front Plant Sci ; 14: 1002943, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37409307

RESUMEN

Soil compaction due to field trafficking involves a complex interplay of machine-soil properties. In contrast to previous studies simulating worst field scenarios, this two-year field experiment investigated the effects of traffic-induced compaction involving moderate machine operational specifications (axle load, 3.16 Mg; mean ground contact pressure, 77.5 kPa) and lower field moisture contents (< field capacity) at the time of trafficking on soil physical properties, spatial root distribution, and corresponding maize growth and grain yield in sandy loam soil. Two compaction levels, i.e. two (C2) and six (C6) vehicle passes, were compared with a control (C0). Two maize (Zea mays L.) cultivars, i.e. ZD-958 and XY-335, were used. Results showed topsoil (< 30 cm) compaction with increases in bulk density (BD) and penetration resistance (PR) up to 16.42% and 127.76%, respectively, in the 10-20 cm soil layer in 2017. Field trafficking resulted in a shallower and stronger hardpan. An increased number of traffic passes (C6) aggravated the effects, and the carryover effect was found. Higher BD and PR impaired root proliferation in deeper layers of topsoil (10-30 cm) and promoted shallow horizontal root distribution. However, XY-335, compared with ZD-958, showed deeper root distribution under compaction. Compaction-induced reductions in root biomass and length densities were respectively up to 41% and 36% in 10-20 cm and 58% and 42% in the 20-30 cm soil layer. Consequent yield penalties (7.6%-15.5%) underscore the detriments of compaction, even only in topsoil. In crux, despite their low magnitude, the negative impacts of field trafficking under moderate machine-field conditions after just two years of annual trafficking foreground the challenge of soil compaction.

12.
Materials (Basel) ; 16(9)2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37176236

RESUMEN

A total of 9 tests were carried out with 30 mm and 78 mm caliber scaled projectiles penetrating into granite targets. The penetration depth, crater diameter, and mass loss rate were examined and discussed. The results indicate that the dimensionless penetration depth of large-caliber projectiles is 20% greater than small-caliber projectiles. Based on the description of static resistance Ra in the Forrestal semi-empirical formula, the size effect of dimensionless penetration depth can be attributed to the size effect of static resistance Ra, and it can be seen that the penetration static resistance of projectile A is 40% higher than that of projectile B. Numerical simulations of projectile penetration into granite targets were conducted using the finite element program ANSYS/LS-DYNA. In terms of penetration depth and crater damage, the numerical simulation results agree well with the test data. This suggests that the selection of parameters was reasonable. The influence of compressive strength, projectile striking velocity, mass, diameter, and caliber-radius-head (CRH) ratio on the static resistance Ra were studied by RHT model parameterization. Based on the numerical results from the parametric study, an empirical formula was derived to predict the static resistance Ra.

13.
Sensors (Basel) ; 23(3)2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36772346

RESUMEN

Soil is the habitat for soil organisms and associated soil physical and chemical processes. The subsoil is a large reserve of water and nutrients. Soil and subsoil are thus significantly involved in the yield capacity of a site and its resilience in the case of unfavorable weather conditions. Subsoil can also retain water in drought phases and stores carbon. In times of climate change and scarcity of resources, many scientific activities involve subsoil and require sensors to assess subsoil conditions and properties. An electrically driven penetrometer with an integrated soil water content sensor could be an appropriate tool for such applications; however, such a subsoil measurement tool does not exist. One major reason for this is that, when penetrating compacted subsoil, high penetration forces (including friction) act on the penetrating thin rod (diameter 1 cm). The development of a tractor-mounted subsoil penetrometer for depths up to 2 m is described in this study. An ASABE standard cone is implemented, which can access heavy compacted layers. The rod, which includes wires for embedding an FDI moisture sensor in the cone tip, is covered by a protection tube. The penetration resistance measurement can be performed without being influenced by shaft friction. The rod, along with the sensor, is implemented in a tower that can be shifted laterally and can take probes in a single line without moving the tractor. To confirm the quality of the developed subsoil penetrometer, a suitable evaluation method is presented. Typical arable soil (loamy silt) was filled in boxes and compacted homogeneously using a hydraulic stamp so that different setups of the penetrometer could be compared and evaluated. The evaluation concludes that the distance between the free cone tip and the protection shaft should be at least 10 cm to measure the penetration resistance of soil without being influenced by the protection tube. Furthermore, the developed penetrometer has sufficient stability and precision for accessing subsoil. In field trials, the subsoil penetrometer was compared with a standard penetrometer and has proved its suitability.

14.
Mol Plant Pathol ; 24(3): 272-283, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36617319

RESUMEN

Nonhost resistance (NHR) refers to the immunity of most tested genotypes of a plant species to most tested variants of a pathogen species. Thus, NHR is broad spectrum and durable in nature and constitutes a major safety barrier against invasion of a myriad of potentially pathogenic microbes in any plants including domesticated crops. Genetic study of NHR is generally more difficult compared to host resistance mainly because NHR is genetically more complicated and often lacks intraspecific polymorphisms. Nevertheless, substantial progress has been made towards the understanding of the molecular basis of NHR in the past two decades using various approaches. Not surprisingly, molecular mechanisms of NHR revealed so far encompasses pathogen-associated molecular pattern-triggered immunity and effector-triggered immunity. In this review, we briefly discuss the inherent difficulty in genetic studies of NHR and summarize the main approaches that have been taken to identify genes contributing to NHR. We also discuss new enabling strategies for dissecting multilayered NHR in model plants with a focus on NHR against filamentous pathogens, especially biotrophic pathogens such as powdery mildew and rust fungi.


Asunto(s)
Basidiomycota , Resistencia a la Enfermedad , Resistencia a la Enfermedad/genética , Genotipo , Productos Agrícolas , Enfermedades de las Plantas/microbiología
15.
Materials (Basel) ; 15(23)2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36500119

RESUMEN

The use of structural lightweight concrete in the construction industry is on the rise in the last few decades mainly because of the higher strength per unit density, as it reduces the total deal load of the structural elements as compared with normal strength concrete. In addition, the environmental concerns of the concrete industry have gained supreme importance in recent times, demanding vital and effectual steps. In this regard, the current study was carried out to formulate an alternative approach for producing a sustainable lightweight structural concrete. The study followed two stages: initially, the selection of optimized manmade plastic aggregates based on trial concrete mixes, and finally, to gauge the physical-, mechanical- and durability related properties of the concretes integrating optimized manmade aggregate series at different replacement fractions. As a result of the first phase: two aggregate series out of eight were selected based on the compressive strength and durability properties of their concretes. In the next stage, all the properties for the optimized aggregate concrete were analyzed in terms of compressive strength. It was noted that the physical, mechanical and chloride penetration resistances have generally displayed a decreasing trend, with an increase in the manmade plastic aggregate replacement fractions as compared with reference lightweight concrete. However, the two aggregates, i.e., 70% DS-30% LLDPE and 50% QF-50% PET at the replacement fractions of 25% and 100%, were found to be the best two contenders that fulfilled the criteria for structural lightweight concrete, i.e., ASTMC330/C330M-14, and were proposed for structural lightweight purposes with low and relatively high strength and chloride resistance-based durability requirements, respectively. In addition, the brittleness ratios and structural efficiency parameters for the concretes of the 70% DS-30% LLDPE and 50% QF-50% PET also supplemented the aforementioned findings. Overall, this study presents a sustainable approach for the effective utilization of plastic waste for producing structural lightweight concrete.

16.
Ying Yong Sheng Tai Xue Bao ; 33(10): 2736-2742, 2022 Oct.
Artículo en Chino | MEDLINE | ID: mdl-36384609

RESUMEN

The planting effect and the planting potential of 12 cover crops (Leguminous: alfalfa, smooth vetch, hairy vetch, red clover, white clover, common vetch; non-leguminous: sudangrass, green radish, Nitro radish, rape, kale, endive) in the Sanjiang Plain of Northeast China were comprehensively evaluated by soil penetration resistance, pre-winter biomass, root characteristics, and plant nitrogen accumulation. The results showed that all the 12 cover crops grew normally during the experimental sowing period. Compared with the control, all the cover crops successfully reduced soil compactness. The planting of green radish, nitro radish, and sudangrass decreased soil penetration resistance by 47.1%, 43.4% and 33.4%, respectively. The pre-winter total fresh biomass of cover crop populations was between 3.38 and 13.98 kg·m-2, and the total dry matter mass was between 0.78 and 2.43 kg·m-2. The biomass of non-leguminous cover crops was significantly higher than that of the leguminous cover crops. The group roots of radish, rape and endive had large volumes. In particular, the nitro radish roots had a vo-lume of 4018.5 cm3·m-2, and the root system of sudangrass extended over the widest horizontal range. The ash content of leguminous cover crops was significantly lower than that of non-leguminous species, which could provide more organic matter with high decomposability. The total nitrogen accumulation of cover crops varied from 18.72 to 53.09 g·m-2. Kale and endive accumulated the highest amount of nitrogen and large biomass, which could facilitate nitrogen fixation and accumulation. According to the type of main crops in Sanjiang Plain and canopy structure, planting leguminous (clover, vetch, and alfalfa) and non-leguminous (radish, kale and sudangrass) cover crops to plant inter-row or in a line mixed cropping pattern could regulate soil structure and promote nutrient cycing, with positive effects on the fertility of black soil in the Sanjiang Plain.


Asunto(s)
Fabaceae , Sorghum , Trifolium , Vicia , Agricultura/métodos , Suelo/química , Productos Agrícolas , Nitrógeno , Biomasa , Verduras
17.
Materials (Basel) ; 15(19)2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36234306

RESUMEN

The useful life of a concrete structure is highly dependent upon its durability, which enables it to withstand the harsh environmental conditions. Resistance of a concrete specimen to rapid chloride ion penetration (RCP) is one of the tests to indirectly measure its durability. The central aim of this study was to investigate the influence of different variables, such as, age, amount of binder, fine aggregate, coarse aggregate, water to binder ratio, metakaolin content and the compressive strength of concrete on the RCP resistance using a genetic programming approach. The number of chromosomes (Nc), genes (Ng) and, the head size (Hs) of the gene expression programming (GEP) model were varied to study their influence on the predicted RCP values. The performance of all the GEP models was assessed using a variety of performance indices, i.e., R2, RMSE and comparison of regression slopes. The optimal GEP model (Model T3) was obtained when the Nc = 100, Hs = 8 and Ng = 3. This model exhibits an R2 of 0.89 and 0.92 in the training and testing phases, respectively. The regression slope analysis revealed that the predicted values are in good agreement with the experimental values, as evident from their higher R2 values. Similarly, parametric analysis was also conducted for the best performing Model T3. The analysis showed that the amount of binder, compressive strength and age of the sample enhanced the RCP resistance of the concrete specimens. Among the different input variables, the RCP resistance sharply increased during initial stages of curing (28-d), thus validating the model results.

18.
Materials (Basel) ; 15(17)2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36079296

RESUMEN

This work investigates the effect of various sand fractions on the ballistic resistance of ultra-high-performance steel-fibre-reinforced concrete (UHP-SFRC) samples. We specifically investigated replacing expensive and generally inaccessible microsands with commonly available sands. The tests and the measured values show that replacing part of the microsand with the more commonly and economically acceptable 0/2 mm aggregate fraction minimises the resulting mechanical properties and ballistic resistance. The most common type of ammunition was used to test all sample bodies, which is a 7.62 × 39 mm calibre with an all-metal jacket and a mild steel core. The damage's extent and mode were determined using a 3D scanner operating on photogrammetry.

19.
Mol Plant Pathol ; 23(10): 1524-1537, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35849420

RESUMEN

In barley (Hordeum vulgare), signalling rat sarcoma homolog (RHO) of plants guanosine triphosphate hydrolases (ROP GTPases) support the penetration success of Blumeria graminis f. sp. hordei but little is known about ROP activation. Guanine nucleotide exchange factors (GEFs) facilitate the exchange of ROP-bound GDP for GTP and thereby turn ROPs into a signalling-activated ROP-GTP state. Plants possess a unique class of GEFs harbouring a plant-specific ROP nucleotide exchanger domain (PRONE). Here, we performed phylogenetic analyses and annotated barley PRONE-GEFs. The leaf epidermal-expressed PRONE-GEF HvGEF14 undergoes a transcriptional down-regulation on inoculation with B. graminis f. sp. hordei and directly interacts with the ROP GTPase and susceptibility factor HvRACB in yeast and in planta. Overexpression of activated HvRACB or of HvGEF14 led to the recruitment of ROP downstream interactor HvRIC171 to the cell periphery. HvGEF14 further supported direct interaction of HvRACB with a HvRACB-GTP-binding CRIB (Cdc42/Rac Interactive Binding motif) domain-containing HvRIC171 truncation. Finally, the overexpression of HvGEF14 caused enhanced susceptibility to fungal entry, while HvGEF14 RNAi provoked a trend to more penetration resistance. HvGEF14 might therefore play a role in the activation of HvRACB in barley epidermal cells during fungal penetration.


Asunto(s)
Hordeum , Ascomicetos , Factores de Intercambio de Guanina Nucleótido/genética , Factores de Intercambio de Guanina Nucleótido/metabolismo , Guanosina Trifosfato/metabolismo , Hordeum/microbiología , Filogenia , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/metabolismo , Internalización del Virus
20.
Artículo en Inglés | MEDLINE | ID: mdl-35682277

RESUMEN

This two-year study was focused on the effect of the application of different biomass ash doses on selected soil physical properties, i.e., soil moisture (SM), bulk density (BD), penetration resistance (PR), and soil stability in water measured by the content of readily dispersible clay (RDC), following control and mineral NPK fertilization in the cultivation of winter oilseed rape (Brassica napus L. var. napus). A one-factor field experiment conducted on podzolic soil (control, NPK, 100, 200, 300, 400, 500 kg K2O·ha-1) showed that the use of biomass combustion ash significantly improved soil moisture at all depths and variants, and especially at a depth of 30-35 cm in the 500 kg·ha-1 variant, i.e., by 2.99% v/v, compared to NPK. In turn, the moisture content in the 30-35 cm layer increased by 3.19% v/v in all variants in both years compared to the control. In 2020 and 2021, bulk density in the 0-5 cm layer treated with a dose of 500 kg·ha-1 exhibited a positive 0.15 and 0.12 Mg·m-3 decrease, respectively, compared to the control. In both years, the BD values in the 30-35 cm layer were reduced by 0.14 and 0.16 Mg·m-3 compared to the control. The PR values decreased in the treatments with doses of 300, 400, and 500 kg·ha-1, especially in 2021. The RDC content was found to decline in both years, i.e., 2020 and 2021, upon the application of even the lowest dose (100 kg·ha-1) in all the analysed layers. The reduction in the RDC content, especially in the 0-5 cm layer, is very important for soil structure stability and to protect the soil environment. This layer is most susceptible to crusting, which results in poor aeration and weak plant emergence during drought and/or periods of excessive moisture. It may also increase surface runoff and intensify soil erosion processes.


Asunto(s)
Brassica napus , Suelo , Biomasa , Arcilla , Estaciones del Año , Suelo/química , Agua
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