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1.
Biomimetics (Basel) ; 8(2)2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37366832

RESUMO

Inspired by nature, oscillating foils offer viable options as alternate energy resources to harness energy from wind and water. Here, we propose a proper orthogonal decomposition (POD)-based reduced-order model (ROM) of power generation by flapping airfoils in conjunction with deep neural networks. Numerical simulations are performed for incompressible flow past a flapping NACA-0012 airfoil at a Reynolds number of 1100 using the Arbitrary Lagrangian-Eulerian approach. The snapshots of the pressure field around the flapping foil are then utilized to construct the pressure POD modes of each case, which serve as the reduced basis to span the solution space. The novelty of the current research relates to the identification, development, and employment of long-short-term neural network (LSTM) models to predict temporal coefficients of the pressure modes. These coefficients, in turn, are used to reconstruct hydrodynamic forces and moment, leading to computations of power. The proposed model takes the known temporal coefficients as inputs and predicts the future temporal coefficients followed by previously estimated temporal coefficients, very similar to traditional ROM. Through the new trained model, we can predict the temporal coefficients for a long time duration that can be far beyond the training time intervals more accurately. It may not be attained by traditional ROMs that lead to erroneous results. Consequently, the flow physics including the forces and moment exerted by fluids can be reconstructed accurately using POD modes as the basis set.

2.
Front Plant Sci ; 13: 898823, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646037

RESUMO

Maize is one of the most important field crops considering its utilization as food, feed, fodder, and biofuel. However, the sustainability of its production is under serious threat of heat and drought stresses, as these stresses could hamper crop growth, causing a significant loss to kernel yield. The research study was carried out at Maize and Millets Research Institute, Yusafwala-Sahiwal for two consecutive spring seasons (2019-20 and 2020-21) under a split-split plot design. The current study explained the individual and combined effects of drought and heat stresses on morphology, phenology, physiology, reactive oxygen species (stocktickerROS), antioxidant status, and kernel quality traits in four indigenous (YH-5482, YH-5427, YH-5404, and YH-1898) and one multinational maize hybrid (P-1543). Stress treatments, i.e., drought, heat, and drought+heat, were applied ten days before tasseling and lasted for 21 days. The results revealed the incidence of oxidative stress due to overproduction of Hydrogen peroxide; H2O2 (control: 1.9, heat+drought: 5.8), and Malondialdehyde; stocktickerMDA (control: 116.5, heat+drought: 193), leading to reduced photosynthetic ability (control: 31.8, heat:16.5), alterations in plant morphology, decrease in kernel yield (control: 10865 kg ha-1, heat+drought: 5564 kg ha-1), and quality-related traits. Although all the stress treatments induced the accumulation of stress-responsive osmolytes and enzymatic antioxidants to cope with the negative impact of osmotic stress, the effect of combined drought + heat stress was much higher. The overall performance of indigenous maize hybrid YH-5427 was much more promising than the other hybrids, attributed to its better tolerance of drought and heat stresses. Such stress tolerance was attributed to maintaining photosynthetic activity, a potent antioxidant and osmolyte-based defense mechanisms, and minimum reductions in yield-related traits, which assured the maximum kernel yield under all stress treatments.

3.
PLoS One ; 17(3): e0265344, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35303032

RESUMO

Wheat (Triticum aestivum L.) is an important staple food crop for one third of global population and important crop for securing future food security. Rapid changes in the climate on global scale could be a threat for future food security. This situation urges plant breeders to explore the genetic potential of existing wheat germplasm. This study screened forty diverse wheat genotypes for their yield under two different agroclimatic conditions, i.e., Layyah and Dera Ghazi Khan, Pakistan. Data relating to plant height, peduncle length, flag leaf area, spike length, number of spikelets, number of grains per spike, thousand grain weight, chlorophyll content and grain yield were recorded. The tested wheat genotypes significantly differed for grain yield and related traits. Grain yield was positively correlated with plant height, spike length, spike number, flag leaf length, number of grains per spike, and 1000-grain weight. Biplot obtained from the cluster analysis by Euclidean method grouped the studied genotypes in 3 different groups. The genotypes exhibited 10.77% variability within quadrants, whereas 72.36% variability was recorded between quadrants according to clustering. Dendrogram grouped the tested genotypes into two main clusters. The main cluster "I" comprised of 2 genotypes, i.e., 'Seher-2006' and 'AS-2002'. The cluster "II" contained 38 genotypes based on Euclidian values. Genotypes within same cluster had smaller D2 values compared to those belonging to other clusters. The genetic relationships of genotypes provide useful information for breeding programs. Overall, the results revealed that genotypes 'Line 9733', 'Bhakar-2002', 'Line A9' and 'SYN-46' had better yield and yield stability under climatic conditions of southern Punjab. Therefore, these genotypes could be recommended for general cultivation in the study region.


Assuntos
Melhoramento Vegetal , Triticum , Grão Comestível/genética , Genótipo , Fenótipo , Triticum/genética
4.
PLoS One ; 17(2): e0262937, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35148345

RESUMO

Wheat is an important crop, used as staple food in numerous countries around the world. However, wheat productivity is low in the developing world due to several biotic and abiotic stresses, particularly drought stress. Non-availability of drought-tolerant wheat genotypes at different growth stages is the major constraint in improving wheat productivity in the developing world. Therefore, screening/developing drought-tolerant genotypes at different growth stages could improve the productivity of wheat. This study assessed seed germination and seedling growth of eight wheat genotypes under polyethylene glycol (PEG)-induced stress. Two PEG-induced osmotic potentials (i.e., -0.6 and -1.2 MPa) were included in the study along with control (0 MPa). Wheat genotypes included in the study were 'KLR-16', 'B6', 'J10', '716', 'A12', 'Seher', 'KTDH-16', and 'J4'. Data relating to seed germination percentage, root and shoot length, fresh and dry weight of roots and shoot, root/shoot length ratio and chlorophyll content were recorded. The studied parameters were significantly altered by individual and interactive effects of genotypes and PEG-induced osmotic potentials. Seed germination and growth parameters were reduced by osmotic potentials; however, huge differences were noted among genotypes. A reduction of 32.83 to 53.50% was recorded in seed germination, 24.611 to 47.75% in root length, 37.83 to 53.72% in shoot length, and 53.35 to 65.16% in root fresh weight. The genotypes, 'J4', 'KLR-16' and 'KTDH-16', particularly 'J4' better tolerated increasing osmotic potentials compared to the rest of the genotypes included in the study. Principal component analysis segregated these genotypes from the rest of the genotypes included in the study indicated that these can be used in the future studies to improve the drought tolerance of wheat crop. The genotype 'J4' can be used as a breeding material to develop drought resistant wheat genotypes.


Assuntos
Germinação/efeitos dos fármacos , Polietilenoglicóis/farmacologia , Plântula/efeitos dos fármacos , Triticum/genética , Secas , Genótipo , Pressão Osmótica , Análise de Componente Principal , Plântula/genética , Plântula/crescimento & desenvolvimento , Sementes/genética , Sementes/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento
5.
Bioengineered ; 12(2): 12702-12721, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34949157

RESUMO

The overuse of cisplatin (>50 mg/m2) is limited to nephrotoxicity, ototoxicity, gastrotoxicity, myelosuppression, and allergic reactions. The objective of this study was to investigate the nephroprotective effects of Daucus carota and Eclipta prostrata extracts on cisplatin-induced nephrotoxicity in Wistar albino rats. The study involved male Wistar albino rats of 8 weeks weighing 220-270 g. A single injection of 5 mg/kg was injected into the rats for nephrotoxicity. Rats were divided into four groups based on dose conentrations. Blood and urine samples of rats were collected on the 0, 7th, 14th, and 21st days for nephrological analysis. The results showed that Cis + DC/Cis + EP (600 mg/kg) significantly (p < 0.001) increased the body weight and reduced the kidney weight of cisplatin-induced nephrotoxicity in rats (p < 0.001) as compared to Cis group. The results showed that 600 mg/kg administration of Cis + DC/Cis +EP successfully (p < 0.005) improved the urine and plasmin creatinine, Na, and K level compared to the Cis group. Histopathological results confirmed that Cis + EP/Cis + DC effectively improved the renal abnormalities. It is concluded that the co-administration of Cis + EP extract showed exceptional nephroprotective effects at a dose rate of 600 mg/kg.


Assuntos
Cisplatino/efeitos adversos , Daucus carota/química , Eclipta/química , Nefropatias/induzido quimicamente , Nefropatias/tratamento farmacológico , Substâncias Protetoras/uso terapêutico , Animais , Peso Corporal/efeitos dos fármacos , Creatinina/sangue , Rim/efeitos dos fármacos , Rim/patologia , Nefropatias/sangue , Nefropatias/urina , Masculino , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Potássio/urina , Substâncias Protetoras/farmacologia , Ratos Wistar , Sódio/urina , Micção/efeitos dos fármacos
6.
J Environ Manage ; 284: 112047, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33571851

RESUMO

Soil pollution with Cd has promoted serious concerns for medicinal plant quality. Amending Cd-polluted soils with textile waste biochar (TWB) coated with natural polymers can lower Cd bioavailability in them and reduce associated environmental and human health risks. In this study, we explored the impacts of solely applied TWB, chitosan (CH), their mix (TWB + CH) and TWB coated with CH (TBC) in Cd-polluted soil on Cd distribution in moringa (Moringa oleifera L.) shoots and roots as well as plant-available Cd in soil. Moreover, amendments effects on plant growth, dietary quality, and antioxidative defense responses were also assessed. Results revealed that the addition of TWB, CH, and TWB + CH in Cd-polluted soil reduced Cd distribution in shoots (56%, 66%, and 63%), roots (41%, 48%, and 45%), and plant-available Cd in soil (38%, 52%, and 49%), compared to control. Interestingly, the TBC showed significantly the topmost response for reducing Cd concentrations in shoots, roots, and soil by 73%, 54%, and 58%, respectively, relative to control. Moreover, amending Cd-polluted soil with TWB, CH, and TWB + CH depicted significantly better effects on plant growth, dietary quality, and activities of soil enzymes but the topmost response was observed with TBC treatment. Compared with control, TBC improved plant growth parameters: shoot length (81%), root length (90%), shoot fresh weight (60%), root fresh weight (76%), shoot dry weight (75%), root dry weight (68%) contents of chlorophyll-a (42%) and chlorophyll-b (74%), and soil enzyme activities: urease (130%), catalase (138%), protease (71%), cellobiohydrolase (45%), acid phosphatase (34%), peroxidase (60%), ß-glucosidase (152%), chitinase (62%), and phosphomonoesterase (139%). Furthermore, TBC treatment arrested Cd-induced oxidative stress via escalating the activities of antioxidant enzymes as well as improved moringa dietary parameters (protein, tannins, lipids, alkaloids, saponins, terpenoids, flavonoids, and tocopherols contents). Such findings suggest that the TBC has an immense perspective to remediate Cd-polluted soils and prevent human health risks associated with Cd exposure through the diet.


Assuntos
Quitosana , Moringa oleifera , Moringa , Poluentes do Solo , Cádmio/análise , Carvão Vegetal , Poluição Ambiental , Humanos , Solo , Poluentes do Solo/análise , Têxteis
7.
Bioinspir Biomim ; 16(1)2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33075763

RESUMO

To understand the governing mechanisms of bio-inspired swimming has always been challenging due to intense interactions between flexible bodies of natural aquatic species and water around them. Advanced modal decomposition techniques provide us with tools to develop more in-depth understating about these complex dynamical systems. In this paper, we employ proper orthogonal decomposition (POD) and dynamic mode decomposition (DMD) techniques to extract energetically strongest spatio-temporal orthonormal components of complex kinematics of a Crevalle jack (Caranx hippos) fish. Then, we present a computational framework for handling fluid-structure interaction related problems in order to investigate their contributions towards the overall dynamics of highly nonlinear systems. We find that the undulating motion of this fish can be described by only two standing-wave like spatially orthonormal modes. Constructing the data set from our numerical simulations for flows over the membranous caudal fin of the jack fish, our modal analyses reveal that only the first few modes receive energy from both the fluid and structure, but the contribution of the structure in the remaining modes is minimal. For the viscous and transitional flow conditions considered here, both spatially and temporally orthonormal modes show strikingly similar coherent flow structures. Our investigations are expected to assist in developing data-driven reduced-order mathematical models to examine the dynamics of bio-inspired swimming robots and develop new and effective control strategies to bring their performance closer to real fish species.


Assuntos
Perciformes , Natação , Animais , Fenômenos Biomecânicos , Peixes , Movimento (Física)
8.
Biomed Res Int ; 2020: 4327651, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083466

RESUMO

Frostbite is caused due to extreme vulnerability to cold, resulting in damage of deeper and superficial tissues alike. In this study, we report the anti-inflammatory and wound-healing properties of aqueous methanolic extract of Cuscuta reflexa (Cs.Cr) against contact frostbite. Thirty rats were divided into five groups including three treatment groups with increasing doses of Cs.Cr, a standard drug group receiving acetylsalicylic acid (ASA), and a metal bar-induced frostbite group. Frostbite injury was induced by a 3 × 3.5 cm metal bar frozen up to -79°C on shaved skin for continuous 3 minutes. Wounded area percentages were recorded to measure the healing rate in response to Cs.Cr administration. Haematological parameters and malondialdehyde content were also noted. On treatment with Cs.Cr, the healing rate is drastically increased and lipid peroxidation product malondialdehyde was decreased in a dose-dependent manner. Results were compared with frostbite and ASA (standard drug group). These results indicate that Cs.Cr possesses excellent wound-healing properties against frostbite injury and can prove to be a prospective compound in such conditions.


Assuntos
Cuscuta , Congelamento das Extremidades , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Estudos Prospectivos , Ratos , Pele/efeitos dos fármacos , Pele/patologia
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