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Spin-orbit torque (SOT)-driven deterministic control of the magnetic state of a ferromagnet with perpendicular magnetic anisotropy is key to next-generation spintronic applications including non-volatile, ultrafast and energy-efficient data-storage devices. However, field-free deterministic switching of perpendicular magnetization remains a challenge because it requires an out-of-plane antidamping torque, which is not allowed in conventional spin-source materials such as heavy metals and topological insulators due to the system's symmetry. The exploitation of low-crystal symmetries in emergent quantum materials offers a unique approach to achieve SOTs with unconventional forms. Here we report an experimental realization of field-free deterministic magnetic switching of a perpendicularly polarized van der Waals magnet employing an out-of-plane antidamping SOT generated in layered WTe2, a quantum material with a low-symmetry crystal structure. Our numerical simulations suggest that the out-of-plane antidamping torque in WTe2 is essential to explain the observed magnetization switching.
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Heavy metals represent a considerable threat, and the current study deals with synthesizing a novel MOF nanocomposite by intercalating graphene oxide (GO) and linker UiO-66-NDC. It was shown that UiO-66-NDC/GO had enhanced the removal efficiency of Pb (II) ions at pH 6. The adsorption kinetics data followed the PSO (Type 2) representing chemisorption. Adsorption data were also fitted with three different isotherms, namely Temkin, Freundlich, & Langmuir, and the Temkin model exhibited the best correlation (R2 0.99), representing the chemisorption nature of the adsorption process. The maximum adsorption capacity (qmax) of Pb (II) ions using Langmuir was found to be 254.45 mg/g (298 K). The Pb (II) adsorption process was confirmed to be exothermic and spontaneous as the thermodynamic parameters H° and G° were determined to have negative values. MOF nanocomposite also represents significant reusability for up to four regeneration cycles using 0.01 M HCl; for the next four, it works quite efficiently after regeneration. Meanwhile, the simulation findings confirm the superior dynamic stability (â¼08 times) of the MOF nanocomposite as compared to the GO system. The removal of Pb (II) from simulated wastewater samples using a super nano-adsorbent using a MOF nanocomposite is described here for the first time.
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Plomo , Contaminantes Químicos del Agua , Adsorción , Contaminantes Químicos del Agua/análisis , Agua , Iones , Cinética , Concentración de Iones de HidrógenoRESUMEN
The development and operation of a nanosensor for detecting the poisonous 1-chloro-3-ethylamino-5-isopropylamino-2,4,6-triazine (Atrazine) are described in this study for the first time. The carbon electrode (CE) surface was modified with cysteine-substituted naphthalene diimide to create this sensitive platform. The developed nanosensor (NDI-cys/GCE) was evaluated for its ability to sense Atrazine using differential pulse voltammetry and cyclic voltammetry. To achieve the best response from the target analyte, the effects of several parameters were examined to optimize the conditions. The cysteine-substituted naphthalene diimide significantly improved the signals of the Atrazine compared to bare GCE due to the synergistic activity of substituted naphthalene diimide and cysteine molecules. Under optimal conditions, atrazine detection limits at the (NDI-cys/GCE) were reported to be 94 nM with a linear range of 10-100 µM. The developed sensing platform also showed positive results when used to detect the atrazine herbicide in real tap water, wastewater, and milk samples. Furthermore, a reasonable recovery rate for real-time studies, repeatability, and stability revealed that the developed electrochemical platform could be used for sample analysis.
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Chemical co-precipitation synthesized novel and green cobalt-oxide nanoparticles (Co3O4-NPs) utilizing cobalt nitrate as cobalt precursors. FTIR, Raman, scanning electron microscopy, UV visible, X-ray powder diffraction, and BET was used to analyze the surface characteristics, composition, and morphology, of the NPs. These green Co3O4-NPs were employed to remove Pb ions from simulated wastewater solutions at various pH, adsorbate, temperature, and dose concentrations. At dose 20 mg/L, pH 6.0, 20 mg/L (Pb(II) solution, 25 °C of temperature, and 45 min for equilibrium, nearly 99.44% of Pb ions were removed. To evaluate the kinetic data, four different kinetic equations were used. The data fit the Elovich rate equation better than the other three models. Thermodynamic and isothermal studies were also evaluated, and the maximum adsorption capacity of 450.45 mg/g was observed at 298.15 K. 0.1 M HNO3, and 0.1 HCl were used to regenerate used Co3O4-NPs. Simulation results show the strong correlation of the Co atom in the Co3O4-NPs generates active delocalized surface states, which are energetically most favorable for heavy metal (Pb ions) adsorption and removal, supporting the experimental outcomes. In concluding remarks, green Co3O4-NPs can also be used as an adsorbent to remove Pb ions from wastewater bodies.
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Nanopartículas , Contaminantes Químicos del Agua , Plomo , Aguas Residuales , Adsorción , Cobalto , Nanopartículas/química , Contaminantes Químicos del Agua/análisis , Cinética , Concentración de Iones de HidrógenoRESUMEN
NixMg1-xFe2O4(x = 0, 0.2, 0.4, 0.6) nanoparticles were symphonized via combustion with microwave assistance in the presence of Tamarindus indica seeds extract as fuel. Nanoparticles nature, size, morphology, oxidation state, elemental composition, and optical and luminescence properties were analysed using PXRD, FTIR, SEM, EDX, and HRTEM with SAED, XPS, UV-Visible and photoluminescence spectroscopy. PXRD analysis confirms that synthesized nanoparticles are spinel cubic and have a 17-18 nm average crystalline size. Tetrahedral and octahedral sites regarding stretching vibrations were confirmed by FTIR analysis. SEM and HRTEM data it is disclosed that the morphology of synthesized nanoparticles has nano flakes-like structure with sponge-like agglomeration. Elemental compositions of prepared nanoparticles were confirmed through EDX spectroscopy. XPS Spectroscopy confirmed and revealed transition, oxidation states, and elemental composition. The band gap and absorption phenomenon were disclosed using UV-visible spectroscopy, where the band gap declines (2.1, 2, 1.6, 1.8 eV), with increase in nickel NixMg1-xFe2O4(x = 0, 0.2, 0.4, 0.6) doping. Photoluminescence intensity reduces with an incline in nickel doping, was confirmed and disclosed using photoluminescence spectroscopy. Dyes (Methylene blue and Rhodamine B) degradation activity was performed in the presence of NDMF nanoparticles as a photocatalyst, which disclosed that 98.1% of MB dye and 97.9% of RB dye were degraded in 0-120 min. Regarding initial dye concentration and catalyst load, 5 ppm was initiated as the ideal initial concentration for both RB and MB dyes. 50 mg catalyst dosage was found to be most effective for the degradation of MB and RB dyes. In comparison, pH studies revealed that photodegradation efficiency was higher in neutral (MB-98.1%, RB-97.9%) and basic (MB-99.6%, RB-99.3%) conditions than in acidic (MB-61.8%, RB-60.4%) conditions.
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Nanopartículas , Níquel , Magnesio , Microondas , Nanopartículas/química , ColorantesRESUMEN
Mimosa pudica L. (MP) is well-known plant in traditional medicinal system, especially in India. Unfortunately, leaves of MP are less explored. To determine the food and nutritional value of the neglected part of Mimosa pudica L. (MP), that is MP leaves, phytochemicals and metal ions of MP were quantified by newly developed HPLC and ICPOES-based methods. The content of phytochemicals observed using HPLC analysis for chlorogenic acid, catechin, and epicatechin was 141.823 (±8.171), 666.621 (±11.432), and 293.175 (±12.743) µg/g, respectively. Using GC/MS/MS analysis, fatty acid like oleic acid were identified. In ICP-OES analysis, a significant content of Na, K, Ca, Cu, Fe, Mg, Mn, and Zn was observed. The observed TPC and TFC for MP leaf extracts was 44.327 (±1.041) mg GAE/ g of wt. and 214.217 (±4.372) mg QCE/ g of wt., respectively. The DPPH assay depicted a strong antioxidant activity of MP leaf extracts with IC50 values of 0.796 (±0.081) mg/mL and a TEAC value of 0.0356 (±0.0003). A significant antacid activity (666â mg MP+400â mg CaCO3 >400â mg CaCO3 â«666â mg Gelusil) of MP leaves was noticed. The methanolic extract of MP leaves demonstrated anti-microbial activity against Staphylococcus aureus (15±2mm), Pseudomonas aeruginosa (12±2mm) and Escherichia coli (10±2mm). In silico studies confirmed the inâ vitro results obtained for antioxidant, antiacid, and anti-microbial activities. In addition, in silico studies revealed the anti-cancerous and anti-inflammatory potential of the MP leaves. In summary, this study demonstrated the medicinal significance of MP leaves and the conversion of agro-waste or the under-utilized part of MP into pharmaceutical potent materials. Consequently, the present study highlighted that MP leaves alone have medicinal importance with good nutritional utility and possess large promise in the pharma industry along with improving bio-valorization and the environment.
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The genus of Salix is used in food, medicine and nutraceuticals, and standardized by using the single marker compound Salicin only. Stem bark is the official part used for the preparation of various drugs, nutraceuticals and food products, which may lead to overexploitation and damage of tree. There is need to search substitution of the stem bark with leaf of Salix alba L. (SA), which is yet not reported. Comparative phytochemicals viz. Salicin, Procyanidin B1 and Catechin were quantified in the various parts of SA viz. heart wood (SA-HW), stem bark (SA-SB) and leaves (SA-L) of Salix alba L.by using newly developed HPLC method. It was observed that SA-HW and SA-L contained far better amount of Salicin, Procyanidin B and Catechin as compared to SA-SB (SA-HW~SA-Lâ«SA-SB). Essential and toxic metal ions of all three parts were analysed using newly developed ICP-OES method, where SA-L were founded as a rich source of micronutrients and essential metal ions as compared to SA-SB and SA-HW. GC-MS analysis has shown the presence of fatty acids and volatile compounds. The observed TPC and TFC values for all three parts were ranged from 2.69 to 32.30â mg GAE/g of wt. and 37.57 to 220.76â mg QCE/g of wt. respectively. In DPPH assay the IC50 values of SA-SB, SA-HW, and SA-L were 1.09 (±0.02), 5.42 (±0.08), and 8.82 (±0.10)â mg/mL, respectively. The order of antibacterial activities against E.â coli, S.â aureus, P.â aeruginosa, and B.â subtilis strains was SA-L>SA-HW>SA-SB with strong antibacterial activities against S.â aureus, and B.â subtilis strains. The antacid activities order was SA-L>SA-SB>SA-HW. The leaves of SA have shown significant source of nutrients, phytochemicals and medicinal properties than SA-HW and SA-SB. The leaves of SA may be considered as substitute of stem bark to save the environment or to avoid over exploitation, but after the complete pharmacological and toxicological studies.
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Antiinfecciosos , Antiulcerosos , Catequina , Salix , Catequina/farmacología , Antioxidantes/análisis , Antiácidos/análisis , Antiácidos/metabolismo , Salix/química , Salix/metabolismo , Madera , Corteza de la Planta/química , Escherichia coli , Staphylococcus aureus , Extractos Vegetales/química , Fitoquímicos/química , Antibacterianos/metabolismo , Hojas de la Planta , Antiinfecciosos/metabolismoRESUMEN
Metal-based adsorbents are limited for hexavalent chromium [Cr(VI)] adsorption from aqueous solutions because of their low adsorption capacities and slow adsorption kinetics. In the present study, decorated zinc oxide (ZnO) nanoparticles (NPs) on graphene oxide (GO) nanoparticles were synthesized via the solvothermal process. The deposition of ZnO NPs on graphene oxide for the nanohybrid (ZnO-GO) improves Cr(VI) mobility in the nanocomposite or nanohybrid, thereby improving the Cr(VI) adsorption kinetics and removal capacity. Surface deposition of ZnO on graphene oxide was characterized through Fourie Transform Infra-red (FTIR), UV-Visible, X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive Spectroscopy (EDS), and Brunauer-Emmett-Teller (BET) techniques. These characterizations suggest the formation of ZnO-GO nanocomposite with a specific area of 32.95 m2/g and pore volume of 0.058 cm2/g. Batch adsorption analysis was carried to evaluate the influence of operational parameters, equilibrium isotherm, adsorption kinetics and thermodynamics. The removal efficiency of Cr(VI) increases with increasing time and adsorbent dosage. FTIR, FESEM and BET analysis before and after the adsorption studies suggest the obvious changes in the surface functionalization and morphology of the ZnO-GO nanocomposites. The removal efficiency increases from high-acidic to neutral pH and continues to decrease under alkaline conditions as well. Mathematical modeling validates that the adsorption follows Langmuir isotherm and fits well with the pseudo 2nd order kinetics (Type 5) model, indicating a homogeneous adsorption process. The thermodynamics study reveals that Cr(VI) adsorption on ZnO-GO is spontaneous, endothermic, and entropy-driven. A negative value of Gibb's Free Energy represents the thermodynamic spontaneity and feasibility of the sorption process. To the best of our knowledge, this is the first study of Cr(VI) removal from aqueous solution using this hybrid nanocomposite at near-neutral pH. The synthesized nanocomposites prove to be excellent candidates for Cr(VI) removal from water bodies and natural wastewater systems.
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Contaminantes Químicos del Agua , Purificación del Agua , Óxido de Zinc , Adsorción , Cromo/análisis , Grafito , Concentración de Iones de Hidrógeno , Cinética , Termodinámica , Contaminantes Químicos del Agua/análisisRESUMEN
Phorate is a systemic insecticide used to eradicate mites, insects, and nematodes. Extensive use of this organophosphate has engendered severe environmental concerns. The current research aimed to explore the kinetic pathways of phorate biodegradation in aqueous solutions. Two novel bacterial strains Pseudomonas aeruginosa strain PR1 (KP268772.1) and Pseudomonas sp. PR_02 (KP268773.1) were isolated, screened, and developed given their potential to degrade phorate. Mineralization of phorate was assayed with and without the addition of metal ions [Fe (II) and Cu (II)] and humic acid (HA). In 14 days, experiment both strains have consumed about 69%-94.5% (half-life from 3.58 to 6.02 days) of phorate. The observed biodegradation rate of phorate with Cu (II) in the system was 73% and 87%, with a half-life of 4.86 and 4.07 days for PR1 and PR2, respectively. The biodegradation of phorate using Fe(II) was 69% and 82%, with half-life periods 5.68 and 4.49 days. Meanwhile, incorporating HA, the phorate biodegradation was inhibited significantly, showing 71% and 85% degradation, with half-life periods of 6.02 and 5.02 days. The results indicated that both bacterial strains were able to mineralize phorate with PR2 > PR1. Summarizing, the inhibition in phorate biodegradation order under different conditions was as HA > Fe (II) > Cu (II). UV-visible measurements and gas chromatography-mass spectrometric assays indicated that the possible degradation pathway of phorate included ethoxy-phosphonothio-methanethiol S-mercaptomethyl-O,O-dihydrogen phosphorodithioate, diethyl-methylphosphonate, methane dithiol, ethanethiol, and phosphate, as the main metabolites identified. Therefore, it was concluded that the newly isolated Pseudomonas strains could be a potential candidates for biodegradation of phorate in a cost-effective, safe, and environmentally friendly alternative.
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Sustancias Húmicas , Forato , Bacterias/metabolismo , Biodegradación Ambiental , Sustancias Húmicas/análisis , Forato/análisis , Forato/metabolismo , Forato/farmacología , Microbiología del SueloRESUMEN
Polyethylene terephthalate is a common plastic in many products such as viscose rayon for clothing, and packaging material in the food and beverage industries. Polyethylene terephthalate has beneficial properties such as light weight, high tensile strength, transparency and gas barrier. Nonetheless, there is actually increasing concern about plastic pollution and toxicity. Here we review the properties, occurrence, toxicity, remediation and analysis of polyethylene terephthalate as macroplastic, mesoplastic, microplastic and nanoplastic. Polyethylene terephthalate occurs in groundwater, drinking water, soils and sediments. Plastic uptake by humans induces diseases such as reducing migration and proliferation of human mesenchymal stem cells of bone marrow and endothelial progenitor cells. Polyethylene terephthalate can be degraded by physical, chemical and biological methods.
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Background: Sepsis in children is a conundrum of diagnostic and therapeutic challenges. There is an exigent need for a novel biomarker that can serve as a clear distinguisher of sepsis from other non-septic inflammatory conditions. The role of presepsin as a biomarker of sepsis in children is still a matter of scientific inquiry. Aim and objectives: To evaluate the diagnostic accuracy of presepsin for the prediction of septic shock, in children aged 1 month to 18 years. Materials and methods: This prospective cohort study was conducted in the pediatric emergency, ward, and intensive care unit of a tertiary care hospital. We enrolled all consecutive admissions aged 1 month to 18 years with a diagnosis of sepsis and compared the presepsin, procalcitonin, and C-reactive protein (CRP) levels on admission (day 1) and 72 hours later (day 4) with the clinical outcomes. Results: The mean (±SD) presepsin values in blood culture-proven sepsis patients at admission and 72 hours later were 609.77 ± 417.30 and 839 ± 748.07, respectively. The procalcitonin and presepsin levels at 72 hours in sepsis patients with shock were significantly elevated (38.2 ± 45.55 and 1129.1 ± 1133.80, respectively) as compared to those without shock (10.7 ± 25.42 and 472.5 ± 507.81, respectively), p <0.05. The receiver operating characteristic (ROC) curve analysis of presepsin at 72 hours had an area under curve (AUC) of 0.730, suggesting a fair diagnostic accuracy. Conclusion: Elevated presepsin levels may indicate greater severity of sepsis, particularly in those with shock. However, it lacks diagnostic ability early in the disease and has limited prognostic potential in predicting mortality. How to cite this article: Khera D, Toteja N, Singh S, Singh S, Kumar P, Sharma P, et al. Is There a Role of Presepsin as a Novel Biomarker in Pediatric Sepsis? Indian J Crit Care Med 2022;26(6):712-716.
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The accelerating energy demands of the increasing global population and industrialization has become a matter of great concern all over the globe. In the present scenario, the world is witnessing a considerably huge energy crisis owing to the limited availability of conventional energy resources and rapid depletion of non-renewable fossil fuels. Therefore, there is a dire need to explore the alternative renewable fuels that can fulfil the energy requirements of the growing population and overcome the intimidating environmental issues like greenhouse gas emissions, global warming, air pollution etc. The use of microorganisms such as bacteria has captured significant interest in the recent era for the conversion of the chemical energy reserved in organic compounds into electrical energy. The versatility of the microorganisms to generate renewable energy fuels from multifarious biological and biomass substrates can abate these ominous concerns to a great extent. For instance, most of the microorganisms can easily transform the carbohydrates into alcohol. Establishing the microbial fuel technology as an alternative source for the generation of renewable energy sources can be a state of art technology owing to its reliability, high efficiency, cleanliness and production of minimally toxic or inclusively non-toxic byproducts. This review paper aims to highlight the key points and techniques used for the employment of bacteria to generate, biofuels and bioenergy, and their foremost benefits.
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Biocombustibles , Biotecnología , Carbohidratos/química , Etanol/química , Etanol/metabolismoRESUMEN
Stress arising due to abiotic factors affects the plant's growth and productivity. Among several existing abiotic stressors like cold, drought, heat, salinity, heavy metal, etc., drought condition tends to affect the plant's growth by inducing two-point effect, i.e., it disturbs the water balance as well as induces toxicity by disturbing the ion homeostasis, thus hindering the growth and productivity of plants, and to survive under this condition, plants have evolved several transportation systems that are involved in regulating the drought stress. The role of membrane transporters has gained interest since genetic engineering came into existence, and they were found to be the important modulators for tolerance, avoidance, ion movements, stomatal movements, etc. Here in this comprehensive review, we have discussed the role of transporters (ABA, protein, carbohydrates, etc.) and channels that aids in withstanding the drought stress as well as the regulatory role of transporters involved in osmotic adjustments arising due to drought stress. This review also provides a gist of hydraulic conductivity by roots that are involved in regulating the drought stress.
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Sequías , Canales Iónicos/metabolismo , Proteínas de Transporte de Membrana/metabolismo , Fenómenos Fisiológicos de las Plantas , Proteínas de Plantas/metabolismo , Ácido Abscísico/metabolismo , Deshidratación , Ingeniería Genética , Canales Iónicos/genética , Proteínas de Transporte de Membrana/genética , Desarrollo de la Planta , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/genética , Raíces de Plantas/fisiologíaRESUMEN
Antibiotics overuse, inappropriate conduct, and discharge have led to adverse effects on various ecosystems. The occurrence of antibiotics in surface and drinking water is a matter of global concern. It is responsible for multiple disorders, including disruption of endocrine hormones and high chronic toxicity. The hospitals, pharmaceutical industries, households, cattle farms, and aquaculture are the primary discharging sources of antibiotics into the environment. This review provides complete detail on applying different nanomaterials or nanoparticles for the efficient removal of antibiotics from the diverse ecosystem with a broader perspective. Efforts have been made to focus on the degradation pathways and mechanism of antibiotic degradation using nanomaterials. More light has been shed on applying nanostructures in photocatalysis, which would be an economical and efficient solution. The nanoscale material or nanoparticles have incredible potential for mineralizing pharmaceutical compounds in aqueous solutions at low cost, easy handling characteristics, and high efficacy. Furthermore, nanoparticles can absorb the pharmaceutical by-products and wastes at a minimum cost as they can be easily recycled. With the increasing number of research in this direction, the valorization of pharmaceutical wastes and by-products will continue to expand as we progress from old conventional approaches towards nanotechnology. The utilization of nanomaterials in pharmaceutical wastewater remediation is discussed with a major focus on valorization, energy generation, and minimization and its role in the circular economy creating sustainable development.
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Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Animales , Bovinos , Ecosistema , Cinética , Aguas Residuales , Contaminantes Químicos del Agua/análisisRESUMEN
The coronavirus disease 2019, COVID-19, caused by the severe acute respiratory syndrome coronavirus 2, SARS-CoV-2, appears as a major pandemic having adverse impact on public health and economic activities. Since viral replication in human enterocytes results in its faecal shedding, wastewater surveillance is an ideal, non-invasive, cost-effective and an early warning epidemiological approach to detect the genetic material of SARS-CoV-2. Here, we review techniques for the detection of SARS-CoV-2 in municipal wastewater, and disinfectants used to control viral spread. For detection, concentration of ribonucleic acid involves ultrafiltration, ultracentrifugation and polyethylene glycol precipitation. Identification is done by reverse transcriptase amplification, nucleic acid sequence-based amplification, helicase dependent amplification, loop-mediated isothermal amplification, recombinase polymerase amplification, high throughput screening and biosensor assays. Disinfectants include ultraviolet radiations, ozone, chlorine dioxide, hypochlorites and hydrogen peroxide. Wastewater surveillance data indicates viral presence within longer detection window, and provides transmission dynamics earlier than classical methods. This is particularly relevant for pre-symptomatic and asymptomatic COVID-19 cases.
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The presence of an electrical transport current in a material is one of the simplest and most important realizations of nonequilibrium physics. The current density breaks the crystalline symmetry and can give rise to dramatic phenomena, such as sliding charge density waves, insulator-to-metal transitions, or gap openings in topologically protected states. Almost nothing is known about how a current influences the electron spectral function, which characterizes most of the solid's electronic, optical, and chemical properties. Here we show that angle-resolved photoemission spectroscopy with a nanoscale light spot provides not only a wealth of information on local equilibrium properties, but also opens the possibility to access the local nonequilibrium spectral function in the presence of a transport current. Unifying spectroscopic and transport measurements in this way allows simultaneous noninvasive local measurements of the composition, structure, many-body effects, and carrier mobility in the presence of high current densities. In the particular case of our graphene-based device, we are able to correlate the presence of structural defects with locally reduced carrier lifetimes in the spectral function and a locally reduced mobility with a spatial resolution of 500 nm.
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In the recent times, plants are facing certain types of environmental stresses, which give rise to formation of reactive oxygen species (ROS) such as hydroxyl radicals, hydrogen peroxides, superoxide anions and so on. These are required by the plants at low concentrations for signal transduction and at high concentrations, they repress plant root growth. Apart from the ROS activities, hydrogen sulfide (H2 S) and nitric oxide (NO) have major contributions in regulating growth and developmental processes in plants, as they also play key roles as signaling molecules and act as chief plant immune defense mechanisms against various biotic as well as abiotic stresses. H2 S and NO are the two pivotal gaseous messengers involved in growth, germination and improved tolerance in plants under stressed and non-stress conditions. H2 S and NO mediate cell signaling in plants as a response to several abiotic stresses like temperature, heavy metal exposure, water and salinity. They alter gene expression levels to induce the synthesis of antioxidant enzymes, osmolytes and also trigger their interactions with each other. However, research has been limited to only cross adaptations and signal transductions. Understanding the change and mechanism of H2 S and NO mediated cell signaling will broaden our knowledge on the various biochemical changes that occur in plant cells related to different stresses. A clear understanding of these molecules in various environmental stresses would help to confer biotechnological applications to protect plants against abiotic stresses and to improve crop productivity.
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Sulfuro de Hidrógeno/metabolismo , Óxido Nítrico/fisiología , Fenómenos Fisiológicos de las Plantas , Transducción de Señal , Estrés Fisiológico , Plantas , Especies Reactivas de OxígenoRESUMEN
We report the experimental observation of sublattice-resolved resonant scattering in bilayer graphene by performing simultaneous cryogenic atomic hydrogen doping and electron transport measurements in an ultrahigh vacuum. This allows us to monitor the hydrogen adsorption on the different sublattices of bilayer graphene without atomic-scale microscopy. Specifically, we detect two distinct resonant scattering peaks in the gate-dependent resistance, which evolve as a function of the atomic hydrogen dosage. Theoretical calculations show that one of the peaks originates from resonant scattering by hydrogen adatoms on the α sublattice (dimer site) while the other originates from hydrogen adatoms on the ß sublattice (nondimer site), thereby enabling a method for characterizing the relative sublattice occupancy via transport measurements. Utilizing this new capability, we investigate the adsorption and thermal desorption of hydrogen adatoms via controlled annealing and conclude that hydrogen adsorption on the ß sublattice is energetically favored. Through site-selective desorption from the α sublattice, we realize hydrogen doping with adatoms primarily on a single sublattice, which is highly desired for generating ferromagnetism.
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Wastewater flowing in streams and nallahs across India carries several trace metals, including metalloid arsenic (As), which are considered serious environmental contaminants due to their toxicity, and recalcitrant nature. In this study, we determined the phytoremediation of As by Eichhornia crassipes (Mart.) Solms either alone or in association with plant growth-promoting rhizobacteria. Pseudomonas and Azotobacter inoculation to E. crassipes resulted in enhanced As removal compared to uninoculated control. Co-inoculation with a consortium of Pseudomonas, Azotobacter, Azospirillum, Actinomyces, and Bacillus resulted in a higher As (p < 0.05) phytoaccumulation efficiency. P. aeruginosa strain jogii was found particularly effective in augmenting As removal by E. crassipes. Our findings indicate that the synergistic association of E. crassipes and various rhizobacteria is an effective strategy to enhance removal of As and thus may be utilized as an efficient biological alternative for the removal of this metalloid from wastewaters.
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Arsénico , Eichhornia , Contaminantes Químicos del Agua , Arsénico/metabolismo , Biodegradación Ambiental , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua/metabolismoRESUMEN
The quality of the tunnel barrier at the ferromagnet/graphene interface plays a pivotal role in graphene spin valves by circumventing the impedance mismatch problem, decreasing interfacial spin dephasing mechanisms and decreasing spin absorption back into the ferromagnet. It is thus crucial to integrate superior tunnel barriers to enhance spin transport and spin accumulation in graphene. Here, we employ a novel tunnel barrier, strontium oxide (SrO), onto graphene to realize high quality spin transport as evidenced by room-temperature spin relaxation times exceeding a nanosecond in graphene on silicon dioxide substrates. Furthermore, the smooth and pinhole-free SrO tunnel barrier grown by molecular beam epitaxy (MBE), which can withstand large charge injection current densities, allows us to experimentally realize large spin accumulation in graphene at room temperature. This work puts graphene on the path to achieve efficient manipulation of nanomagnet magnetization using spin currents in graphene for logic and memory applications.