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In recent years, the emission of greenhouse gases (GHGs) has increased significantly, contributing to global warming. Among these GHGs, CH4, CO2, and CO are particularly potent contributors. Remediation techniques primarily rely on materials capable of capturing, storing, and converting these gases. Catalytic processes, particularly heterogeneous catalysis, are essential to chemical and petrochemical industries as well as environmental remediation. Due to the growing demand for catalysts, efforts are being made to reduce energy consumption and make technologies more environmentally friendly. Green chemistry emphasizes minimizing the use of hazardous reactants and harmful solvents in chemical processes. Achieving these principles should be paired with processes that reduce time and costs in catalyst preparation while improving their efficiency. Non-thermal plasma (NTP) has been widely used for the preparation of supported metal catalysts. NTP has attracted significant attention for its ability to improve the physicochemical properties of catalysts, enhancing process efficiency through low-temperature operation and shorter processing times. NTP has been applied to various catalyst synthesis techniques, including reduction, oxidation, metal oxide doping, surface etching, coating, alloy formation, surface treatment, and surface cleaning. Plasma-prepared transition-metal catalysts offer advantages over conventionally prepared catalysts due to their unique material properties. These properties enhance catalytic activity by lowering the activation energy barrier, improving stability, and increasing conversion and selectivity compared to untreated samples. This review demonstrates how plasma activation modifies material properties and, based on extensive literature, illustrates its potential to combat climate change by converting CO2, CH4, CO, and other gases, showcasing the benefits of plasma-treated materials and catalysts. A succinct introduction to this review outlines the advantages of plasma-based synthesis and modification over traditional synthesis techniques. The introduction also highlights the various types of plasma and their physical characteristics across different factors. Additionally, this review addresses methods by which materials are synthesized and modified using plasma. The latter section of this review discusses the use of non-thermal plasma for greenhouse gas mitigation, covering applications such as the dry reforming of CH4, CO and CH4 oxidation, CO2 reduction, and other uses of plasma-modified catalysts. [ABSTRACT FROM AUTHOR]

We analysed the BSi (Biogenic Silica) contents of the marine core SK-313/1 from the southeastern Arabian Sea which is dated up to ~14.5 kyr BP. Results show that the maximum and minimum BSi contents are 2.5 and 0.5%, respectively. This is because of the low supply of silica skeleton and the high dissolution and dilution of terrigenous materials. The BSi mass accumulation rates indicate a trend of reduced paleoproductivity during the late Glacial period and increase during the Holocene, with global climatic shifts. Insolation changes at low latitudes, which regulate temperatures, may affect nutrient availability and, consequently productivity variations on a glacial–interglacial timescale. Notably, millennial events like the Younger Dryas (YD) periods, exhibited lower paleoproductivity, in contrast to the Bølling/Allerød (B-A) period and the middle Holocene, which displayed elevated levels of paleoproductivity. These millennial-scale fluctuations in siliceous productivity may be due to the changes in nutrient supply caused by the Indian summer monsoon (ISM). The period of increased paleoproductivity could be influenced by intensified chemical weathering and a boosted nutrient supply, which are consequences of the strengthened ISM during periods of relatively higher temperature. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to synthesize and test Mn-Sb/TiO2-CNT catalysts with different Sb/Mn molar ratios to be used in NH3-SCR reaction. Design/methodology/approach: A series of Sb-loaded carbon nanotubes (CNTs)-based Mn/TiO2 catalysts were prepared by the incipient wetness co-impregnation method and tested for the selective catalytic reduction (SCR) of NOx with NH3. Findings: The Sb-loaded Mn/TiO2-CNTs catalyst outperformed other catalysts and presented the highest activity in the temperature regime of 100–400°C. The catalyst loaded with Sb also showed good SO2 and H2O resistance and exhibited better thermal stability. A stepwise study of SO2 addition evidenced that Mn-Sb/TiO2-CNTs catalyst exhibited better SO2 resistance than the base catalyst Mn/TiO2, where the Sb doping greatly inhibited the sulphating of active phase of the catalyst. Originality/value: In Sb-loaded catalysts, the formed SOx species fused with SbOx instead of MnOx. This favoured interaction of SO2 with SbOx successfully prevents the MnOx from being sulphated by SO2 which substantially improves the SO2 tolerance of Sb-loaded catalysts. [ABSTRACT FROM AUTHOR]

In this work, we investigated the impacts of atmospheric pressure dielectric barrier discharge (DBD), i.e., plasma treatment, on pearl millet seeds germination and plant growth. The effect of plasma discharge on water activation, by introducing the reactive species, was explored. We evidenced that about 30 min plasma treated pearl millet seeds exhibited 20% higher germination rate than the control seed watered with tap water. The HR-SEM study revealed that the plasma treatment increased the roughness and FTIR study showed that new oxygen functional groups were introduced on the seed surface. Moreover, it was observed that the water contact angle decreased for plasma treated seeds (50%) and the water uptake also increased considerably as compared to control seeds. These findings indicate that the seed surface has turned more hydrophilic after plasma treatment. A cylindrical double dielectric barrier discharge (D-DBD) reactor was employed for water activation, and 30 min of treatment under air has decreased the pH of deionized water from 7.4 to 4.5 and produced about 1.78 ppm of nitrate (NO3−) and 4.2 ppm of hydrogen peroxide (H2O2). Interestingly, the plasma activated water (PAW) improved the pearl millet seed germination by 30% (after 24 h of sowing) and plant growth as compared to tap water and deionized water. Remarkably, when PAW and plasma-treated seeds were combined, a beneficial impact in seed germination (95 ± 2%) and seedling growth have been evidenced owing to synergistic effect. We evidenced that among the long-lived species in PAW, NO3− enhanced the seed germination and plant growth under similar conditions. These findings demonstrate that the proposed cold plasma reactors could be utilized to boost seed germination and plant growth.Please confirm if the author names are presented accurately and in the correct sequence (given name, middle name/initial, family name). Author 4 Given name: [Amine Aymen] Last name [Assadi]. Also, kindly confirm the details in the metadata are correct.Yes, all author names are correctly editted. [ABSTRACT FROM AUTHOR]

Mineralization of gaseous chlorobenzene (major VOC from cement plants) was studied in a continuous reactor using three advanced oxidation processes: (i) photocatalysis, (ii) Dielectric Barrier Discharge (DBD) plasma and (iii) DBD/TiO2-UV coupling. The work showed an overproduction of OH * and O * radicals in the reaction medium due to the interaction of Cl * and O3. A parametric study was carried out in order to determine the evolution of the removal efficiency as a function of the concentration, the flow rate and the applied voltage. Indeed, a variation of the flow rate from 0.25 to 1 m3/h resulted in a decrease in the degradation rate from 18 to 9%. Similarly, an increase in concentration from 13 to 100 mg/m3 resulted in a change in degradation rate from 18 to 4%. When the voltage was doubled from 6 to 12 kV, the degradation rate varied from 22 to 29 % (plasma) and from 53 to 75% (coupling) at 13 mg/m3. The evolution of COX and O3 was monitored during the experiments. When the voltage was doubled, the selectivity increased from 28 to 37% in the plasma alone and from 48 to 62 % in the coupled process. In addition, at this same voltage range, the amount of ozone formed varied from 10 to 66 ppm in plasma and 3 to 29 ppm in coupling. This degradation performance can be linked to a synergistic effect, which resulted in an increase in the intensity of the electric field of plasma by the TiO2 and the improvement in the performance of the catalyst following the bombardment of various high-energy particles of the plasma. [ABSTRACT FROM AUTHOR]

Though mastitis is caused by multiple etiological agents, bacteria are the most common etiological agents. The molecular detection of an organism is less time-consuming and more accurate than conventional methods, hence the present study was aimed at conventional as well as molecular detection and the antibiogram study of E. coli from the suspected subclinical (15) and clinical (15) mastitis milk samples collected in Puducherry’s Aryankuppam region. All the collected samples were positive for the California Mastitis Test. Subsequently, 19 E. coli isolates were isolated, and they were investigated using the PCR technique (uspA gene) as well as biochemical tests. Twelve samples were found positive by PCR (uspA gene). Furthermore, an antibiogram study revealed that penicillin (100%) was highly resistant, followed by nalidixic acid (78%). Notably, the highest susceptibility was observed for ciprofloxacin (92%), followed by gentamicin (85%), and ceftriaxone (71%). The probable isolates obtained need to be additionally investigated using more mastitis milk samples. [ABSTRACT FROM AUTHOR]

Video surveillance plays a vital role in ensuring security in public and private places over the globe. Facial image analysis using computer vision (CV) and artificial intelligence (AI) based tools become essential. Automated age and gender classification in facial image analysis is a primary process that finds useful in several real time applications such as target advertisements, forensics, human computer, etc. But age and gender classification remains a challenging process due to differences in visual angle, facial expression, background, and facial image appearance. It is more challenging in the unconstrained imaging conditions. In this aspect, this article introduces an automated deep convolutional neural network based age and gender classification (ADCNN-AGC) model using facial images. The proposed ADCNN-AGC model aims for determining the age and gender of the persons who exist in the facial images. To accomplish this, the ADCNN-AGC model follows a two stage process namely face recognition and age/gender classification. Primarily, Multi-task Cascaded Convolutional Networks (MTCNN) model is utilized for the detection of faces in the input images. Besides, the Efficient Net model is applied for the proper extraction of feature vectors which are then passed into the One-Dimensional Convolutional Neural Network (1-DCNN) for classification procedure. The performance validation of the ADCNN-AGC model has been tested using benchmark datasets and the outcomes are observed in many aspects. The experimental outcomes reported the enhanced performance of the ADCNN-AGC model over recent state of art approaches. [ABSTRACT FROM AUTHOR]

We investigated the effect of cell-surface display of glutamate decarboxylase (GadB) on gamma-aminobutyric acid (GABA) production in recombinant Escherichia coli.We integrated GadB fromthe hyperthermophilic, anaerobic archaeon Pyrococcus horikoshii to the C-terminus of the E. coli outermembrane protein C (OmpC). After 12 hr of culturing GadB-displaying cells, the GABA concentration in the extracellularmedium increased to 3.2 g/l, which is eight times that obtained with cells expressing GadB in the cytosol. To further enhance GABA production,we increased the temperatures of the culture. At 60°C, the obtained GABA concentration was 4.62 g/l after 12 hr of culture, and 5.35 g/l after 24 hr, which corresponds to a yield of 87.7%. [ABSTRACT FROM AUTHOR]

The present study combines nonthermal plasma (NTP) and thermal catalysis to exploit the synergism for direct conversion of CO2 to CH3OH using H2. Series of catalyst, that is, CuO/QW, NiO/QW, Fe2O3/QW, NiO/Fe2O3/QW, CuO/Fe2O3/QW have been tested for CO2 conversion and CH3OH selectivity. And it was observed that 5 wt% CuO/Fe2O3/QW exhibited better CO2 conversion and CH3OH selectivity as compared to other catalysts. With 5 wt% CuO/Fe2O3/QW, at 200°C and 2‐W NTP input power (100 ml/min feed flow and 1:3 ratio of CO2 and H2) about 16.7% CO2 conversion and 32.7% CH3OH selectivity have been reached. Indeed, the highest of 9.32 mmol h−1 gcat−1 of CH3OH space‐time yield is obtained over CuO/Fe2O3/QW, which is about two times higher than the reported value in the literature (4.41 mmol h−1 gcat−1 of CH3OH using Cu/ZnO/Al2O3, 30°C, feed flow 40 ml/min, and 30‐W input power). [ABSTRACT FROM AUTHOR]

To produce malic acid from non-oxidative pathway route in Escherichia coli using two key enzymes and synthetic scaffold complex. E. coli was engineered to produce malic acid from glucose by co-localization of two key enzymes phosphoenolpyruvate carboxylase (Ppc) and malate dehydrogenase (MdhA) with synthetic scaffold complex. Scaffold plasmid has produced the maximum concentration of 3.51 g/L malic acid from 10 g/L glucose in 48 h of culture. pH 5.5 and temperature 30°C were optimum for malic acid production without any engineering of competing metabolic pathways. E. coli mutant strains and different concentrations of glucose also tested. When 50 g/L glucose was used as substrate, 20.4 g/L of malic acid was produced. [ABSTRACT FROM AUTHOR]

Peptide-displaying Escherichia coli cells were investigated for use in adsorptive removal of bisphenol A (BPA) both in Luria-Bertani medium including BPA or ATM thermal paper eluted wastewater. Two recombinant strains were constructed with monomeric and dimeric repeats of the 7-mer BPA-binding peptide (KSLENSY), respectively. Greater than threefold increased adsorption of BPA [230.4 µmol BPA per g dry cell weight (DCW)] was found in dimeric peptide-displaying cells compared to monomeric strains (63.4 µmol per g DCW) in 15 ppm BPA solution. The selective removal of BPA from a mixture of BPA analogs (bisphenol F and bisphenol S) was verified in both monomeric and dimeric peptide-displaying cells. The binding chemistry of BPA with the peptide was assumed, based on molecular docking analysis, to be the interaction of BPA with serine and asparagine residues within the 7-mer peptide sequence. The peptide-displaying cells also functioned efficiently in thermal paper eluted wastewater containing 14.5 ppm BPA. [ABSTRACT FROM AUTHOR]

Recently, malic acid has gained attention due to its potential application in food, pharmaceutical, and medical industries. In this study, the synthetic scaffold complex strategy was employed between the two key enzymes pyruvate kinase (PykF) and malic enzyme (SfcA); SH3 ligand was attached to PykF, and the SH3 domain was attached to the C-terminus of ScfA. Synthetic scaffold systems can organize enzymes spatially and temporally to increase the local concentration of intermediates. In a flask culture, the recombinant strain harboring scaffold complex produced a maximum concentration of 5.72 g/L malic acid from 10 g/L glucose. The malic acid production was significantly increased 2.1-fold from the initial culture period. Finally, malic acid production was elevated to 30.2 g in a 5 L bioreactor from recombinant strain XL-1 blue. [ABSTRACT FROM AUTHOR]

The combination of a sub-microsecond pulsed dielectric barrier discharge with Pd/γ-AlO catalyst was investigated for the oxidation of low concentration of methane, propene, and toluene in air at atmospheric pressure. The systematic comparison of the plasma-catalysis with the thermal-catalysis and the plasma-alone have been made for temperature window of 20-400 °C and energy deposition in the range 23-148 J L. To emphasis the reactivity of plasma produced species on the activation of the catalyst, two reactor configurations were used [in-plasma catalysis (IPC), and post-plasma catalysis (PPC)]. Fourier transform infrared spectrometer was used to follow the VOCs conversion and to quantify the mineralized products. The plasma-catalyst combination leads to higher VOCs conversion and decreases the catalyst activation temperature in both IPC and PPC configurations. For hybrid system, the light-off temperature is always lower than those observed for catalytic oxidation. In addition, the formation of the by-products such as formaldehyde, formic acid, and ozone was reduced significantly. A significant synergetic effect of hybrid plasma-catalytic system is not really observed in the presence of CH and CH. However, for CH oxidation the synergetic effect was demonstrated at low temperature (<150 °C) for the IPC configuration. [ABSTRACT FROM AUTHOR]

In general, gamma-aminobutyric acid (GABA) pathway involves the decarboxylation of glutamate, which is produced from sugar by Corynebacterium fermentation. GABA can be used for the production of pharmaceuticals and functional foods. Due to the increasing demand of GABA, it is essential to create an effective alternative pathway for the GABA production. In this study, Escherichia coli were engineered to produce GABA from glucose via GABA shunt, which consists of succinate dehydrogenase, succinate-semialdehyde dehydrogenase, and GABA aminotransferase. The three enzymes were physically attached to each other through a synthetic scaffold, and the Krebs cycle flux was redirected to the GABA pathway. By introduction of synthetic scaffold, 0.75 g/l of GABA was produced from 10 g/l of glucose at 30 °C and pH 6.5. The inactivation of competing metabolic pathways provided 15.4 % increase in the final GABA concentration. [ABSTRACT FROM AUTHOR]

Nylon 4 is a biodegradable polymer which can be produced from the monomer of pyrrolidone. Gammaaminobutyric acid (GABA) is a precursor of pyrrolidone used for the production of bioplastics. In this study, Escherichia coli were engineered to produce gammaaminobutyric acid from glucose via an alternative novel pathway by the introduction of synthetic scaffolds. The GABA pathway constructed contained succinate dehydrogenase, succinate-semialdehyde dehydrogenase and GABA aminotransferase to redirect the Krebs cycle flux to GABA production. By introduction of a synthetic scaffold, production of 0.64 g/L GABA was achieved at 30°C and pH 6.5. Final GABA concentration was increased by 11.3% via the inactivation of competing pathways, and higher initial glucose concentration led to the enhanced final GABA concentration of 1.01 g/L. [ABSTRACT FROM AUTHOR]

Objectives: To direct the carbon flux from Krebs cycle into the gamma-aminobutyric acid (GABA) shunt pathway for the production of GABA by protein scaffold introduction in Escherichia coli. Results: Escherichia coli was engineered to produce GABA from glucose by the co-localization of enzymes succinate semialdehyde dehydrogenase (GadD), GABA aminotransferase (PuuE) and GABA transporter (GadC) by protein scaffold. 0.7 g GABA l was produced from 10 g glucose l while no GABA was produced in wild type E. coli. pH 6 and 30 °C were optimum for GABA production, and GABA concentration increased to 1.12 g GABA l when 20 g glucose l was used. When competing metabolic networks were inactivated, GABA increased by 24 % (0.87 g GABA l). Conclusions: The novel GABA production system was constructed by co-localization of GABA shunt enzymes. [ABSTRACT FROM AUTHOR]

Gamma-aminobutyric acid (GABA) is an important bio-product, which is used in pharmaceutical formulations, nutritional supplements, and biopolymer monomer. The traditional GABA process involves the decarboxylation of glutamate. However, the direct production of GABA from glucose is a more efficient process. To construct the recombinant strains of Escherichia coli, a novel synthetic scaffold was introduced. By carrying out the co-localization of glutamate synthase, glutamate decarboxylase, and GABA transporter, we redirected the TCA cycle flux to GABA pathway. The genetically engineered E. coli strain produced 1.08 g/L of GABA from 10 g/L of initial glucose. Thus, with the introduction of a synthetic scaffold, we increased GABA production by 2.2-fold. The final GABA concentration was increased by 21.8 % by inactivating competing pathways. [ABSTRACT FROM AUTHOR]

Improvement of indoor air quality regarding volatile organic compounds (VOCs) requires the development of innovative oxidation processes. This paper investigates the coupling of a metal oxide sorbent with non-thermal plasma (NTP) in an especially designed reactor. TiO was selected as model sorbent and acetone was used as model VOC. The analyses of gas phase species at the reactor downstream have been performed using FTIR spectroscopy. In a first step, acetone adsorption on TiO surface under dry air was characterized in terms of total amount adsorbed, as well as reversibly and irreversibly adsorbed fractions. Obtained results were compared and discussed with literature in terms of acetone reactive adsorption on TiO surface. Mesityloxide was proposed as the major compound in the irreversibly adsorbed fraction. In a second time, acetone saturated TiO surface was exposed to NTP surface discharge. Irrespectively of the injected power, <30 % of the initially adsorbed acetone has been recovered as CO, CO and desorbed acetone. Finally, thermal desorptions have been performed. They evidenced that (1) NTP treatment modifies the nature of the adsorbed organic species, (2) mineralization rate is considerably improved. Based on desorbed species temporal profile analysis, carboxylates and more especially formates are suggested as major adsorbed species after NTP treatment (P > 0.2 W). This hypothesis has been evaluated and confirmed. This paper finally evidenced that NTP can be used as an efficient pretreatment technique to promote the mineralization of adsorbed acetone for further thermal treatment. [ABSTRACT FROM AUTHOR]

Oxidative decomposition of low concentrations (50-1000 ppm) of diluted benzene in air was carried out in a nonthermal plasma (NTP) dielectric barrier discharge (DBD) reactor with the inner electrode made up of stainless steel fibres (SMF) modified with transition metal oxides in such a way to integrate the catalyst in discharge zone. Typical results indicate the better performance of MnO and TiO/MnO modified systems, which may be attributed to the in situ decomposition of ozone on the surface of MnO that may lead to the formation of atomic oxygen; whereas ultraviolet light induced photocatalytic oxidation may be taking place with TiO modified systems. Water vapour improved the selectivity to total oxidation. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The first part of the review summarizes the problem of air pollution and related air-cleaning technologies. Volatile organic compounds in particular have various effects on health and their abatement is a key issue. Different ways to couple non-thermal plasmas with catalytic or adsorbing materials are listed. In particular, a comparison between in-plasma and post-plasma coupling is made. Studies dealing with plasma-induced heterogeneous reactivity are analysed, as well as the possible modifications of the catalyst surface under plasma exposure. As an alternative to the conventional and widely studied plasma–catalyst coupling, a sequential approach has been recently proposed whereby pollutants are first adsorbed onto the material, then oxidized by switching on the plasma. Such a sequential approach is reviewed in detail. [ABSTRACT FROM AUTHOR]