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Abstract Textile dyes are frequently disposable in aqueous effluents, making it difficult to remove them from industrial effluents before their release to natural waters. This paper deals with the fabrication of cellulose-based adsorbents by reacting nanocelulose crystalline (nanocel) with N-[3-(trimethoxysilyl)propyl]ethylenediamine (TMSPEDA), forming the hybrid (silylpropyl)ethylenediamine@nanocellulose (SPEDA@nanocel), which was employed as adsorbent for the uptake of reactive yellow 2 dye (RY-2) from aqueous effluents. Characterisation of SPEDA@nanocel was carried out using FTIR, SEM–EDS, XRD, TGA, surface area, pHpzc, and hydrophobicity/hydrophilicity ratio (HI). Also, adsorption studies were thoroughly investigated. The effect of initial pH indicated that the maximum uptake of RY-2 takes place at pH 2, which is an indication of the electrostatic mechanism. The kinetic data carried out with 250 and 500 mg L−1 RY-2 with SPEDA@nanocel followed better the nonlinear fractional-like pseudo-first-order model. The t0.5 and t0.95 for the dye uptake were about 30 and 141 min, respectively. The equilibrium data from 10 to 45 °C indicated that the Liu isotherm model was the best-fitted isothermal model. The maximum sorption capacity attained was 112.3 mg g−1 at 45 °C. The thermodynamic data have shown that the equilibrium was favorable and endothermic, and the ΔH° was compatible with an electrostatic attraction between RY-2 and SPEDA@nanocel. Experiments of desorption of loaded adsorbent showed promising results for real applications since at least 5 adsorption/desorption cycles could be employed without significant changes in the recovery and with high precision.

Herein, a novel sulfur-doped carbon material has been synthesized via a facile and sustainable single-step pyrolysis method using lignin-sulfonate (LS), a by-product of the sulfite pulping process, as a novel carbon precursor and zinc chloride as a chemical activator. The sulfur doping process had a remarkable impact on the LS-sulfur carbon structure. Moreover, it was found that sulfur doping also had an important impact on sodium diclofenac removal from aqueous solutions due to the introduction of S-functionalities on the carbon material’s surface. The doping process effectively increased the carbon specific surface area (SSA), i.e., 1758 m2 g−1 for the sulfur-doped and 753 m2 g−1 for the non-doped carbon. The sulfur-doped carbon exhibited more sulfur states/functionalities than the non-doped, highlighting the successful chemical modification of the material. As a result, the adsorptive performance of the sulfur-doped carbon was remarkably improved. Diclofenac adsorption experiments indicated that the kinetics was better described by the Avrami fractional order model, while the equilibrium studies indicated that the Liu model gave the best fit. The kinetics was much faster for the sulfur-doped carbon, and the maximum adsorption capacity was 301.6 mg g−1 for non-doped and 473.8 mg g−1 for the sulfur-doped carbon. The overall adsorption seems to be a contribution of multiple mechanisms, such as pore filling and electrostatic interaction. When tested to treat lab-made effluents, the samples presented excellent performance.

Pesticides usage has tremendously increased to enhance crop production; however some pesticides are toxic and harmful to human health and the environment. This review discusses the eco-toxicological impacts of pesticides on the environment. This study extensively evaluates various sustainable remediation technologies such as advanced oxidation processes (AOPs), electrochemical processes, membrane separation, and adsorbent types (carbon nanotubes, carbon nanofiber, carbon aerogel, graphene oxide, carbon dot, biochar, biosorbents, polymers, metal-organic framework, and nanocomposite) that are used for removal of toxic pesticides from aqueous bodies. Further, various equilibrium isotherm and kinetic models that are used for understanding the mechanisms along with challenges in the techniques are discussed. From the studies, it is observed that the nanocomposites could degrade and remove pesticides efficiently due to their unique properties, making them promising adsorbents for water and wastewater remediation. This review will be an inclusive paper for readers to easily define research gaps and develop novel treatment methods for removing pesticide-contaminated waters.

Zeolites are microporous crystalline aluminosilicates with high surface area and uniform pore size. Natural and synthetic zeolites have been used to adsorb organic and inorganic compounds in aqueous media due to thier particular physicochemical properties and the low cost of the process. The flexibility of zeolites to remove pollutants from water, such as dyes, heavy metal ions, and phenolic compounds, is discussed in this document in the context of contemporary research. This review briefly consolidates the currently available literature to comprehend the structure of zeolites and their synthesized by hydrothermal method. Later, this manuscript is present different parameters to study the adsorption mechanisms of organic and inorganic contaminants using the zeolites. The main adsorption processes using zeolites as adsorbents include chelation, surface adsorption, natural processes, diffusion, electrostatic interaction and complexation. In addition, the research demonstrates that the dominant models in the isothermal and kinetic study of adsorption are the Langmuir and the pseudo-second-order models. We can assess the beneficial applicability of zeolite materials for real wastewater treatment in the future by comparing their adsorption capacities for removing harmful substances from water to those of other adsorbents and crude zeolites.

This review article evaluates and compares the efficiency of various sustainable adsorbents for the removal of noxious pollutants from water environments. This study discusses the various types of adsorbents concerning their performance and suitability. Adsorbent types include natural-based, carbon-based, waste-based, biomass-based, biopolymers-based, and nanocomposites-based adsorbents, as well as metallic organic frameworks, aerogels, networking crystalline solids, zeolite nanoparticles, and dendrimers were reviewed. Characterisation, modification, fabrication, adsorption capacities under different conditions, isotherm models, and kinetics of noxious pollutants were also reviewed. Adsorption capacities for different pH values, adsorbent doses, adsorbent concentrations, temperature, and the size of particles have been described. One of the basic needs in water and wastewater adsorbents is their formulation and optimisation, using columnar operations, and more importantly, they can be produced quickly and should be cost-effective. Various studies reported a broad range of values for the thermodynamic parameters for noxious pollutants, suggesting the adsorbent's nature as an essential factor affecting the thermodynamics of noxious pollutant sorption. The regeneration and reusability potential of other adsorbents have also been discussed, along with molecular modelling, simulation, knowledge gaps, and future perspectives of noxious pollutants from the water environments.

Abstract Several studies have been directed to find scalable, swift, accurate, and cost‐effective strategies for detecting, monitoring, and treating coronavirus disease 2019 (COVID‐19). Indeed, the lack of a fast and practical method for detecting the infected regions makes decision‐making challenging to combat the critical pandemic‐struck situations. The probable ‘wrong’, or rather inadequate, decisions not only have a boomerang effect on the economy but also can lead to an increase in the number of infected individuals, degree of hospitalization, and death counts. Although the current clinical methods are effective, they are costly, time‐consuming, and, more particularly, inadequate because of the virus's mutation patterns. In addition, contamination of biomedical wastes with the COVID‐19 virus is a matter of grave concern. Therefore, there is a perpetual need for novel methodologies to delineate the contaminated regions and determine whether those viruses contaminate the wastewater. Although several review papers have been recently published to discuss those concerns, there is a lack of a comprehensive survey of the detection and treatment of the COVID‐19 virus in aqueous media. Herein, we review techniques available as spreading signifiers for detecting the COVID‐19 virus in water resources and wastewater. We classify and integrate techniques into wastewater, sewage, and sludge detection and monitoring. Treatment of COVID‐19‐contaminated wastewater is discussed by classifying and ranking the methodologies nurtured from nanotechnology, including nanoparticle‐based biosensors used in the detection and nanotechnology‐based filtration systems for the removal of COVID‐19 from wastewater. We also highlight the compilation of the detection methodologies in contaminated aqueous media and provide insight into the challenges associated with treating COVID‐19‐contaminated wastewater. The article concludes that international and robust guidelines for virus/bacteria treatment in wastewater are urgently needed to protect the environment and public health, where nanotechnology plays a key role.

To increase the agricultural production, nano fertilizers have allowed the development of new technologies. In this study, zinc oxide nanoparticles (ZnO-NPs), iron oxide nanoparticles (FeO-NPs) and magnesium oxide nanoparticles (MgO-NPs) have been prepared and applied on the medicinal plants (Caesalpinia bonducella) to increase the yield, nutrient and chlorophyll contents. This study intended to compare the impacts of synthesised NPs with the control plants and their conventional fertilizers such as ZnSO4·7H2O (Zn-bulk), FeSO4·7H2O (Fe-bulk) and MgSO4·7H2O (Mg-bulk). All fertilizers were applied in a completely randomized design including six treatments and three replications of each treatment by using a combination of seed priming method and soil mixing process. Moreover, the NPs were also compared for the best gaining of results. The concentrations selected for applications were 10, 20, 30, 40 ppm for iron and magnesium fertilizers and 25, 50, 75, 100 ppm for zinc-based fertilizers. The results indicated the increase in morphological parameters of the plants of 28–50% by the application of conventional fertilizers while 50–93% by NPs application as compared to control plants. Furthermore, the increase in chlorophyll contents was 5–28% with conventional fertilizers while 30–80% in case of NPs application than control plants. The obtained results indicate that the best increase in growth, nutrient and chlorophyll contents of plants were achieved at the dose concentrations of 40 ppm for Mg and Fe fertilizers and 100 ppm for Zn fertilizers. The comparative study of NPs showed that the highest growth and yield was obtained by the use of ZnO-NPs in comparison to others. Finally, it is worth highlighting that NPs have a huge potential to increase the productivity of crops if applied in optimal concentrations.

This study explored the effects of solution pH, biosorbent dose, contact time, and temperature on the Pb(II) biosorption process of natural and chemically treated leaves of A. compressa K. (Raw-AC and AC-OH, respectively). The results show that the surface characteristics of Raw-AC changed following alkali treatment. FT-IR analysis showed the presence of various functional groups on the surface of the biosorbent, which were binding sites for the Pb(II) biosorption. The nonlinear pseudo-second-order kinetic model was found to be the best fitted to the experimental kinetic data. Adsorption equilibrium data at pH = 2–6, biosorbents dose from 5 to 20 mg/L, and temperature from 300.15 to 333.15 K were adjusted to the Langmuir, Freundlich, and Dubinin–Radushkevich (D-R) isotherm models. The results show that the adsorption capacity was enhanced with the increase in the solution pH and diminished with the increase in the temperature and biosorbent dose. It was also found that AC-OH is more effective than Raw-AC in removing Pb(II) from aqueous solutions. This was also confirmed using artificial neural networks and genetic algorithms, where it was demonstrated that the improvement was around 57.7%. The nonlinear Langmuir isotherm model was the best fitted, and the maximum adsorption capacities of Raw-AC and AC-OH were 96 mg/g and 170 mg/g, respectively. The removal efficiency of Pb(II) was maintained approximately after three adsorption and desorption cycles using 0.5 M HCl as an eluent. This research delved into the impact of solution pH, biosorbent characteristics, and operational parameters on Pb(II) biosorption, offering valuable insights for engineering education by illustrating the practical application of fundamental chemical and kinetic principles to enhance the design and optimization of sustainable water treatment systems.

The Hymnoptera order includes several flower-visiting insects (e.g. ants, bees, and wasps) and the coexistence of many different species in the same community can generate interspecific competition. Notwithstanding shared communities, research which evaluates how these taxonomic groups influence a whole community of flower-visiting Hymenoptera is lacking. Moreover, abiotic factors can also impact these floral visits, because each organism responds differently to climatic variations. The goal of this study is to evaluate abiotic factors, specifically relative air humidity and air temperature, which may be able to impact the number and the frequency of interactions between hymenopterans and flowers and to assess the composition and niche organization, by making use of interaction networks, of the entire community of flower-visiting Hymenoptera at the botanical garden of the Universidade Federal Rural do Rio de Janeiro. For the duration of a year, we took samples in that botanical garden, compartmentalizing the collections temporally in accordance with the time of the insects’ shift (morning or afternoon). We observed a positive influence of air temperature on the number of ant interactions and visits. It is also possible to observe that most of these interaction networks exhibited a nested and non-modular pattern and an average level of network specialization. In addition, bees stood out as the species with the highest frequency of visits and with the most generalist behavior. This study demonstrates how a botanical garden can sustain a diverse community of floral visiting Hymenoptera in an urban environment and why it consists in an important tool for biodiversity conservation.

The reason for the increasing bioavailability and biocompatibility of the porous nanomaterials in the presence of different (bio)molecules is still unknown. The role of difference functional groups and their interactions with the potential bioavailability and biocompatibility is of great importance. To investigate the potential contribution of the electronic effects (especially on the surface of the porous nanomaterials) on their biomedical behavior, a series of surface-decorated green ZnCr-layered double hydroxide (LDH) porous nanocarriers is developed as a non-viral vector. Different conjugations investigated these porous LDHs for optimizing and minimizing the cytotoxicity for targeted breast cancer therapy. Quick low-temperature synthesized ZnCr-LDH nanocarriers method with enlarged drug delivery windows decorated with leaf extracts and benzamide-like molecules revealed a push-pull electronic synergistic effect on cytotoxicity and enhanced cell viability, biocompatibility, aggregations, and interactions with the cell membranes. The pre-defined model drug, doxorubicin (DOX), unraveled chemotherapy performance in response to MCF-7 cell lines, with ≈ 60% drug payload contributed from functional groups of leaf extracts. Moreover, electron-poor and electron-rich benzamide-like molecules attached to the ZnCr-LDH surface enhanced the relative cell viability up to 29% and 32%, respectively. The in vivo experiments on breast cancer of treated mice (H&E) revealed unaggregated cellular arrays and antibacterial activity against E. coli (gram-negative) and S. aureus (gram-positive) bacteria. Benzamide-like ZnCr-LDH nanocarriers showed a suitable zone of inhibition beyond 10 mm, compared to the standard. Cytotoxicity control achieved herein seems promising for the future ahead of nanomedicine.

Novel shellfish waste-derived chitosan (CS) has been developed to adsorb As(V) from simulated wastewater under evaluating adsorption process parameters. The coexistence of some competing ions, like SiO32-, Cl-, NO3– and PO43- as well as the regeneration capacity of the spent adsorbent, was explored. The experimental data were modeled using several kinetics and isotherm models to understand the mechanism related to the uptake process. As(V) uptake was relatively rapid and highly dependent on pH. The Avrami-fractional-order expression supported data best, while the Liu equation described well isotherm data at pH 5.0. The maximum uptake capability (Liu) was 12.32 mg/g, and the highest removal performance (99 %) was obtained at optimum pH 5.0. Molecular dynamics simulations were performed to more clearly illuminate the atomic-level interactions between arsenic species and CS surface in both acidic and basic mediums. After four adsorption–desorption cycles, CS exhibited more than 90 % As(V) removal efficiency. The results of this study indicates that low cost shellfish derived chitosan is promising for efficient removal of As(V) from water body and can be used to remove other pollutants from watewater.

A one-pot synthesis method was conceptualized and implemented to develop green carbon-based nanocomposites working as biosensors. Porphyrin was synthesized to adorn the surface of nanocomposites making them highly sensitive for giving rise to π-π interactions between the genetic materials, proteins and porphyrin rings. The hydrogen bond formed between the proteins (analytes) and the nitrogen in the porphyrin structure as well as the surface hydroxyl groups was equally probable. In this context, different forms of porphyrins were incorporated to explore the interrelationship between the surface morphology and the ability of detection of genetic material and/or proteins by the aid of the synthesized structures. This phenomenon was conceptualized to optimize the interactions between the biomolecules and the substrate by reaching significant biosensor application in the presence of Anti-cas9 protein and sgRNA (concentration changed between 10 and 500 n mol/L). Almost full quenching of fluorescence emission was observed after addition of 300 n mol/L of Anti-cas9 protein and 250 n mol/L of sgRNA. Surprisingly, CoNi2S4 provided 12%–29% cytotoxicity in both HEK-293 and PC12 cell lines.

Abstract Background No biomarker is available for identifying cancer patients at risk of developing nephrotoxicity when treated with cisplatin. Methods We performed microRNA (miRNA) sequencing using plasma collected 5 days after cisplatin treatment (D5) from twelve patients with head and neck cancer with and without nephrotoxicity (grade ≥ 2 increased serum creatinine). The most differentially expressed miRNAs between the two groups were selected for quantification at baseline and D5 in a larger cohort of patients. The association between miRNAs and nephrotoxicity was evaluated by calculating the odds ratio (OR) from univariate logistic regression. Receiver operating characteristic curves (ROC) were used to estimate the area under the curve (AUC), sensitivity, and specificity. Results MiR-3168 (p = 1.98 × 10− 8), miR-4718 (p = 4.24 × 10− 5), and miR-6125 (p = 6.60 × 10− 5) were the most differentially expressed miRNAs and were further quantified in 43, 48, and 53 patients, respectively. The baseline expression of miR-3168 (p = 0.0456, OR = 1.03, 95% CI: 1.00–1.06) and miR-4718 (p = 0.0388, OR = 1.56, 95% CI: 1.03–2.46) were associated with an increased risk of nephrotoxicity, whereas miR-6125 showed a trend (p = 0.0618, OR = 1.73, 95% CI: 0.98–3.29). MiR-4718 showed the highest AUC (0.77, 95% CI: 0.61–0.93) with sensitivity of 66.76 and specificity of 79.49. Conclusions We have provided evidence of baseline plasmatic expression of miR-3168, miR-6125, and miR-4718 as potential predictors of cisplatin-induced nephrotoxicity.

In this study, a purified diatomite (PD) with a concentration of diatom frustules more than 92% SiO2 was utilized to synthesize a composite of MCM-41 silica under hydrothermal conditions. The as-synthesized PD/MCM-41 composite was characterized and tested as an adsorbent for the removal of Cr(VI) and Mn(VII) ions from aqueous solution. Results of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier-transform infrared spectroscopy (FTIR) revealed that the diatom frustules of the PD were coated with MCM-41 mesoporous silica. Experimental isotherms of Cr(VI) and Mn(VII) adsorption were fitted to classical and advanced statistical physics models at 25°C–55°C and pH 3. The Langmuir model estimated monolayer adsorption capacities ranging from 144.1 to 162.2 mg/g for Cr(VI) and 166.2 to 177.0 mg/g for Mn(VII), which improved with increasing the solution temperature. Steric and energetic parameters obtained from a monolayer adsorption model with one adsorption site was utilized to explain the adsorption mechanism at a microscopic level. The number of Cr(VI) and Mn(VII) ions adsorbed on PD/MCM-41 active site (n) were 1.25–1.27 for Cr(VI) and 1.27–1.32 for Mn(VII), thus suggesting multi-interaction mechanisms. The density of PD/MCM-41 active sites (DM) was a key parameter to explain the adsorption of these heavy metals. The adsorbed quantities were maximum at 55°C, thus obtaining 102.8 and 110.7 mg/g for Cr(VI) and Mn(VII), respectively. Cr(VI) and Mn(VII) adsorption energies ranged from 18.48 to 26.70 kJ/mol and corresponded to an endothermic adsorption with physical forces. Entropy, free enthalpy, and internal energy associated to the adsorption of Cr(VI) and Mn(VII) ions were calculated, thus indicating that the removal of these pollutants was spontaneous. Overall, this article offers new interpretations for the Cr(VI) and Mn(VII) adsorption mechanisms on PD/MCM-41 composite, which are relevant to contribute to the development of effective water treatment processes.

In this study, silica@chitosan-glutaraldehyde (Si@Cs-G) was synthesized as a novel adsorbent for extraction of Penicillin G (PG) from the synthetic and real samples followed by HPLC determination. The synthesized adsorbents were characterized by the scanning electron microscopy (SEM), X-ray diffraction (XRD), fourier transform infrared (FTIR), dynamic light scattering (DLS), transmission electron microscopy (TEM) and nitrogen adsorption–desorption techniques. The factors influencing the extraction efficiency including pH, sorbent dose, extraction time, extraction solvent type and its volume were investigated and optimized.Under the optimal conditions (sorbent dosage: 25 mg, desorption solvent (acetonitrile) with volume of 0.75 mL; pH: 6 and extraction time: 50 min), the Si@Cs-G demonstrated high efficiency and linearity (R2 > 0.999) with the concentration of penicillin G ranging from 1 to 300 μg L−1. Extraction recovery in synthetic samples was 98.977%, with LOD = 0.493 μg L−1, LOQ = 1.638 μg L−1 and RSD

Abstract Wastewater treatment is of great concern in the textile industries because dyes, which are released into wastewater, are stable due to their structures and that some of the existing conventional techniques are not effective for aqueous removal of dyes. Among the advanced techniques for treatment of industrial effluents, adsorption is one of the most effective processes for removal of dyes from industrial wastewater. Similarly, activated carbons from different sources have been successfully applied as adsorbents for dye removal from aqueous solutions. In this context, this research evaluated the performance of activated carbon produced from peach pit (APC-1.0) for removal of a textile dye, Procion Red MX-5B (PR-5B), through batch adsorption process. The characteristic features of the peach activated carbon were obtained through Fourier transforms infrared spectroscopy, and scanning electron microscopy. The effectiveness of the activated to remove PR-5B from aqua system was compared with that of commercial activated carbon (CAC). In the kinetic study, the contact time was evaluated between 0 and 480 min using two different initial concentrations. Adsorption isotherms of PR-5B onto the two adsorbents were investigated in six different temperatures (298–326 K). The thermodynamic parameters of the process indicated spontaneous and exothermic adsorption. Equilibrium data were best described by Liu isotherm model with maximum removal capacities of 297.2 and 174.0 mg g−1 for APC-1.0 and CAC, respectively.

This work proposes a facile methodology for producing porous biochar material (ABC) from açaí kernel residue, produced by chemical impregnation with ZnCl2 (1:1) and pyrolysis at 650.0 °C. The characterization was achieved using several techniques, and the biochar material was employed as an adsorbent to remove catechol. The results show that ABC carbon has hydrophilic properties. The specific surface area and total pore volume are 1315 m2·g−1 and 0.7038 cm3·g−1, respectively. FTIR revealed the presence of oxygenated groups, which can influence catechol adsorption. The TGA/DTG indicated that the sample is thermally stable even at 580 °C. Adsorption studies showed that equilibrium was achieved in Qmax is 339.5 mg·g−1 (40 °C) with 98.36% removal of simulated effluent, showing that açaí kernel is excellent biomass to prepare good biochar that can be efficiently used to treat real industrial effluents.

An accelerated carbonation method was applied to improve the ability of recycled aggregates to store CO2 through the rolling carbonation process; moreover, recycled concrete aggregates’ physicochemical properties to produce secondary aggregates for civil engineering applications were explored and evaluated. The carbonation tests were carried out in a laboratory-scale air-proof rotating drum equipped with a CO2 feeding system. Performing carbonation in a rotating drum promotes selective attrition of concrete aggregates. The process accelerates the carbonation by removing the carbonated zones on the surface of coarse aggregates and then facilitating the access of CO2 to un-carbonated zones. The tests were performed at normal atmospheric conditions, with a partial pressure of CO2 kept at about 0.75 bar. The optimal initial moisture of the concrete aggregate was found. The main tests were conducted on 10/20 mm aggregate, but it was shown that the carbonation process was 20% faster for smaller size aggregate (5/8 mm). The rolling speed, initial moisture content, and mass amount played an important role in CO2 sequestration. The most efficient rotating carbonation condition was reached at 100 rpm, aggregate moisture around 8%, and 500 g of aggregates in a 5 L reactor at any partial pressure.The dynamic process highly increased the carbonation kinetics compared with static carbonation of the same duration. The CO2 sequestered was up 80 mg/g of aggregate, estimated to be around 60% of the potential of CO2 capture of the tested recycled concrete aggregate. The number of revolutions appears to be a relevant process parameter concerning the carbonation kinetics. The carbonation duration acts in a complementary way as in a static process.Some physical properties of the recycled concrete aggregate were determined. As a result, the carbonation process reduced water absorption and enhanced the density of the aggregates.

The present work was carried out to evaluate the removal of Coomassie brilliant blue dye by adsorption onto a magnetized activated carbon nanocomposite (MNSA) prepared from Nigella sativa L. (NS) waste. Different techniques, including infrared spectroscopy, scanning electron microscopy, and nitrogen adsorption/desorption, were used to characterize MNSA to investigate its adsorption properties. Adsorption experiments were carried out by simultaneously optimizing four variables that usually present a strong effect in adsorption studies. A full 24 factorial design with 3 central points was used. The four independent variables were the initial pH of the dye solution (pH), the initial dye concentration (Co), the adsorbent mass (m), and the contact time (t). The sorption capacity (q) of the adsorbent and the percentage of dye removal (% Rem) from an aqueous solution were used as the responses of the factorial design. The results indicated that pH, Co, and m were essential factors for the overall optimization of both responses (q and % Rem) and that several interactions of two, three and four factors occurred. Based on the design of the experiments (DOE), the optimized conditions for adsorption were pH = 2.00, Co = 40.0 mg L−1, m = 30.0 mg, and t = 3.0 h. Under these conditions, both responses, q and % Rem, were maximized, with a desirability of 85.54%. The findings of this study could be useful for industrial wastewater treatment systems. Keywords: Nigella sativa L. waste, Nanocomposite, Coomassie brilliant blue, Central composite design, Adsorption

In this work, Norway spruce bark was used as a precursor to prepare activated biochars (BCs) via chemical activation with potassium hydroxide (KOH) as a chemical activator. A Box–Behnken design (BBD) was conducted to evaluate and identify the optimal conditions to reach high specific surface area and high mass yield of BC samples. The studied BC preparation parameters and their levels were as follows: pyrolysis temperature (700, 800, and 900 °C), holding time (1, 2, and 3 h), and ratio of the biomass: chemical activator of 1: 1, 1.5, and 2. The planned BBD yielded BC with extremely high SSA values, up to 2209 m2·g−1. In addition, the BCs were physiochemically characterized, and the results indicated that the BCs exhibited disordered carbon structures and presented a high quantity of O-bearing functional groups on their surfaces, which might improve their adsorption performance towards organic pollutant removal. The BC with the highest SSA value was then employed as an adsorbent to remove Evans blue dye (EB) and colorful effluents. The kinetic study followed a general-order (GO) model, as the most suitable model to describe the experimental data, while the Redlich–Peterson model fitted the equilibrium data better. The EB adsorption capacity was 396.1 mg·g−1. The employment of the BC in the treatment of synthetic effluents, with several dyes and other organic and inorganic compounds, returned a high percentage of removal degree up to 87.7%. Desorption and cyclability tests showed that the biochar can be efficiently regenerated, maintaining an adsorption capacity of 75% after 4 adsorption–desorption cycles. The results of this work pointed out that Norway spruce bark indeed is a promising precursor for producing biochars with very promising properties.

Orchids form endomycorrhizal associations with fungi mainly belonging to basidiomycetes. The molecular events taking place in orchid mycorrhiza are poorly understood, although the cellular changes necessary to accommodate the fungus and to control nutrient exchanges imply a modulation of gene expression. Here, we used proteomics and transcriptomics to identify changes in the steady-state levels of proteins and transcripts in the roots of the green terrestrial orchid Oeceoclades maculata. When mycorrhizal and non-mycorrhizal roots from the same individuals were compared, 94 proteins showed differential accumulation using the label-free protein quantitation approach, 86 using isobaric tagging and 60 using 2D-differential electrophoresis. After de novo assembly of transcriptomic data, 11,179 plant transcripts were found to be differentially expressed, and 2175 were successfully annotated. The annotated plant transcripts allowed the identification of up- and down-regulated metabolic pathways. Overall, proteomics and transcriptomics revealed, in mycorrhizal roots, increased levels of transcription factors and nutrient transporters, as well as ethylene-related proteins. The expression pattern of proteins and transcripts involved in plant defense responses suggested that plant defense was reduced in O. maculata mycorrhizal roots sampled in nature. These results expand our current knowledge towards a better understanding of the orchid mycorrhizal symbiosis in adult plants under natural conditions.

The application of guar gum for pyrite depression in seawater flotation was assessed through microflotation tests, Focused Beam Reflectance Measurements (FBRM), and Particle Vision Measurements (PVM). Potassium amyl xanthate (PAX) and methyl isobutyl carbinol (MIBC) were used as collector and frother, respectively. Chemical species on the pyrite surface were characterized by Fourier-transform infrared spectroscopy (FTIR) spectroscopy. The microflotation tests were performed at pH 8, which is the pH at the copper sulfide processing plants that operate with seawater. Pyrite flotation recovery was correlated with FBRM and PVM characterization to delineate the pyrite depression mechanisms by the guar gum. The high flotation recovery of pyrite with PAX was significantly lowered by guar gum, indicating that this polysaccharide could be used as an effective depressant in flotation with sea water. FTIR analysis showed that PAX and guar gum co-adsorbed on the pyrite surface, but the highly hydrophilic nature of the guar gum embedded the hydrophobicity due to the PAX. FBRM and PVM revealed that the guar gum promoted the formation of flocs whose size depended on the addition of guar gum and PAX. It is proposed that the highest pyrite depression occurred not only because of the hydrophilicity induced by the guar gum, but also due to the formation of large flocs, which could not be transported by the bubbles to the froth phase. Furthermore, it is shown that an overdose of guar gum hindered the depression effect due to redispersion of the flocs.

This study investigated the influence of sodium restriction and antihypertensive drugs on atherogenesis utilizing hypertensive (H) low-density lipoprotein-receptor knockout mice treated or not with losartan (Los) or hydralazine (Hyd) and fed low-sodium (LS) or normal-sodium (NS) chow. Despite reducing the blood pressure (BP) of H-LS mice, the LS diet caused arterial lipid infiltration due to increased plasma total cholesterol (TC) and triglycerides (TG). Los and Hyd reduced the BP of H-LS mice, and Los effectively prevented arterial injury, likely by reducing plasma TG and nonesterified fatty acids. Aortic lipid infiltration was lower in Los-treated H-LS mice (H-LS+Los) than in normotensive (N)-LS and H-LS mice. Aortic angiotensin II type 1 (AT1) receptor content was greater in H-NS than H-LS mice and in H-LS+Hyd than H-LS+Los mice. Carboxymethyl-lysine (CML) and receptor for advanced glycation end products (RAGE) immunostaining was greater in H-LS than H-NS mice. CML and RAGE levels were lower in LS animals treated with antihypertensive drugs, and Hyd enhanced the AT1 receptor level. Hyd also increased the gene expression of F4/80 but not tumor necrosis factor-α, interleukin (IL)-1β, IL-6, IL-10, intercellular adhesion molecule-1 or cluster of differentiation 66. The novelty of the current study is that in a murine model of simultaneous hypertension and hyperlipidemia, the pleiotropic effect of chronic, severe sodium restriction elicited aortic damage even with reduced BP. These negative effects on the arterial wall were reduced by AT1 receptor antagonism, demonstrating the influence of angiotensin II in atherogenesis induced by a severely LS diet.

The Ceará Plateau offshore Fortaleza holds some particular characteristics when compared to the other seamounts of the Brazilian Equatorial Margin (BEM). Not only it is the largest and the closest to the continent, it is also located at the boundary between the continental and the oceanic crusts, while all the others seamounts along the BEM are located on oceanic crust. Seismic imaging of the Ceará Plateau shows a disorganized interior, probably of volcanic origin, overlain by a series of horizontal seismic reflectors that can be interpreted as pelagic/hemipelagic sediments. As large uncertainties exist about the age of the initial formation of this seamount, three scenarios must be considered. If the age of the volcanic edifice is Coniacian (1), then the overlying pelagic/hemipelagic sedimentary succession can include an almost continuous record of the last ~90 Ma at the Equatorial Atlantic Ocean. In the case that the volcanic edifice is Eocene in age (2), the sedimentary sequence would still encompass the upper Paleogene and all the Neogene. There is also the possibility that the volcanic edifice was built during multiple magmatic events (3). In this case, it is likely that the sediments are interfingered with volcanic rocks at the edge of the structure. Although the age estimation (between Coniacian and Eocene) has an uncertainty of more than 40 Myr, the current interpretation is that it developed initially as a volcanic edifice, formed by a series of magmatic events that occurred between the Santonian and the Eocene. Since then, the topography has been leveled by pelagic/hemipelagic sedimentation. Whichever was the initial age, a continuous and constant sequence of sediments deposited onto the Ceará Plateau, at the same latitude, and thus under the same oceanographic conditions, for the last several tens of million years. This represents a unique opportunity to record a long-term history of the Atlantic Equatorial Margin.

The effect of alkali metal chlorides on the viscoelastic behavior and yielding properties of silica suspensions was studied through creep-recovery and dynamic oscillatory tests with stress control. Then, the viscoelasticity of the pulps was correlated with the silica zeta potential, aggregate size, and the percentage of cations adsorbed on the surface of the ore. The results indicate that larger cations are more prone to adhere to the silica surface, which increases the number of ionic bonds that bind the particles. This generates stronger particle networks and a greater agglomeration of particles, especially those smaller than 10 µm. As the size of the bare cations increases, the rheological response provides higher values of yield stress, complex viscosity, and viscoelastic moduli, but in turn, pulps undergo minor deformations under the application of stress. Dynamic oscillatory tests suggest structural changes, with the phase angle following the inverse relationship with the bare cation size, indicating that the liquid-like character of the pulps increases as the size of the cations increases.

Multi-walled and single-walled carbon nanotubes were used as adsorbents for the removal of Reactive Blue 4 textile dye from aqueous solutions. The adsorbents were characterised using Raman spectroscopy, N2 adsorption/desorption isotherms and scanning and transmission electron microscopy. The effects of pH, agitation time and temperature on adsorption capacity were studied. In the acidic pH region, the adsorption of the dye was favourable using both adsorbents. The contact time to obtain equilibrium isotherms at 298-323 K was fixed at 4 hours for both adsorbents. For Reactive Blue 4 dye, Liu isotherm model gave the best fit for the equilibrium data. The maximum sorption capacity for adsorption of the dye occurred at 323 K, attaining values of 502.5 and 567.7 mg g-1 for MWCNT and SWCNT, respectively.

In order to reduce the total number of experiments for achieving the highest amount of adsorbed Cu2+ (qmax) using pecan nutshells (Carya illinoensis) as biosorbent, a full 2(4) factorial design with two central points was carried out (mass of biosorbent- m, pH, initial metallic ion concentration- C0, time of contact- t). In order to continue the optimization of the system, a central composite surface analysis design with two factors and five central points was carried out. The maximum amount of Cu2+ taken up by the pecan nutshells was 20 mg g-1. These results were confirmed by determining a Cu2+ isotherm using the best conditions attained by the statistical design of experiments.

BackgroundThe tetracyclic triterpene euphol is the main constituent found in the sap of Euphorbia tirucalli. This plant is widely known in Brazilian traditional medicine for its use in the treatment of several kinds of cancer, including leukaemia, prostate and breast cancers. Here, we investigated the effect of euphol on experimental models of colitis and the underlying mechanisms involved in its action.Methodology/principal findingsColitis was induced in mice either with dextran sulfate sodium (DSS) or with 2,4,6-trinitrobenzene sulfonic acid (TNBS), and the effect of euphol (3, 10 and 30 mg/kg) on colonic injury was assessed. Pro-inflammatory mediators and cytokines were measured by immunohistochemistry, enzyme-Linked immunoabsorbent assay (ELISA), real time-polymerase chain reaction (RT-PCR) and flow cytometry. Preventive and therapeutic oral administration of euphol attenuated both DSS- and TNBS-induced acute colitis as observed by a significant reduction of the disease activity index (DAI), histological/microscopic damage score and myeloperoxidase (MPO) activity in colonic tissue. Likewise, euphol treatment also inhibited colon tissue levels and expression of IL-1β, CXCL1/KC, MCP-1, MIP-2, TNF-α and IL-6, while reducing NOS2, VEGF and Ki67 expression in colonic tissue. This action seems to be likely associated with inhibition of activation of nuclear factor-κB (NF-κB). In addition, euphol decreased LPS-induced MCP-1, TNF-α, IL-6 and IFN-γ, but increased IL-10 secretion from bone marrow-derived macrophages in vitro. Of note, euphol, at the same schedule of treatment, markedly inhibited both selectin (P- and E-selectin) and integrin (ICAM-1, VCAM-1 and LFA-1) expression in colonic tissue.Conclusions/significanceTogether, these results clearly demonstrated that orally-administered euphol, both preventive or therapeutic treatment were effective in reducing the severity of colitis in two models of chemically-induced mouse colitis and suggest this plant-derived compound might be a potential molecule in the management of inflammatory bowel diseases.