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The goal of this study is to use a simple approach to synthesize pectin from grapefruit peel, an agricultural waste common in tropical regions. Additionally, the study employed optimization techniques to identify the ideal conditions for the maximum extraction efficiency while also determining the importance of studying factors. Besides, extracted pectin characteristics are also presented in this research. Under several analysis, some chemical groups for pectin were presented in extracted pectin by Fourier transform infrared spectroscopy analysis (FTIR). For instance, C-H methyl groups at the peak 1442 cm-1; methyl ester groups C=O appears at the wavelength 1747 cm-1 and aliphatic C-H groups and hydroxyl groups. Furthermore, under three major conditions acid (%); temperature and time extraction, an optimization study was conducted to figure out the optimal conditions for pectin extraction efficiency. Under optimal conditions acid 10%; 77.5 °C and 80 mins is the favorable condition for obtaining pectin extraction efficiency. Basically, this study is the first one extracting pectin from rosy-pulp pomelo peel by sulfuric acid-ethanol precipitation method. This is a preliminary that lays the foundation for purifying extracted pectin from rosy-pulp pomelo, also solving this agricultural waste bring higher economic values.

The current work illustrates how successfully rice husk-activated carbon eliminates hexavalent chromium from aqueous solutions. The design of experiment (DOE) - response surface methodology (RSM) was utilized to build an appropriate experimental model. The experimental variables pH, contact length, and adsorbent dose were found, as well as their interactions and effects on Cr(VI) removal. The greatest result for Cr(VI) removal was obtained at pH = 2, agitation time of about 30.5 hours, and adsorbent dose = 4 g/l, with a starting hexavalent chromium content of 100 ppm. Hexavalent chromium removal is performed optimally under the parameters specified for these driving forces. ANOVA also demonstrated a strong coefficient of determination R2 > 99 %. Furthermore, Temkin isotherm and pseudosecond kinetic models with high R2 values were selected as useful for the inquiry. It illustrates that the removal of hexavalent chromium in studies is considered to follow a regular distribution of binding energies up to a given maximum binding energy. Furthermore, the rate of adsorption site occupancy is inversely proportional to the square of the number of unoccupied sites on the adsorbent.

A transition metal‐free Se‐catalyzed C−H amination protocol for α'‐amination of enol derivatives has been developed. This reaction can be used to functionalize a wide variety of oxygen‐ and halogen‐substituted alkenes spanning a vast range of nucleophilicities, giving α'‐aminated enol derivatives with high regioselectivity. Amination of E/Z mixtures of alkenes proceeds stereoconvergently to give the (Z)‐enol derivatives exclusively. Mechanistic studies revealed that the relative reactivity and α'‐regioselectivity of these transformations is determined by substantial resonance donation to the heteroatom‐bound carbon in the transition state. These products participate in traditional reactions of enol derivatives, allowing for efficient functionalization of both α‐ and α'‐positions from a single enol derivative with high diastereocontrol. [ABSTRACT FROM AUTHOR]

Enhancing user experience in music listening through facial emotion recognition presents a novel avenue for curating personalized song playlists, obviating the need for traditional search methodologies like keyword inputs or manual playlist exploration. This research pivots towards leveraging advanced pre-trained models, specifically ResNet18 and VGG19, for the accurate detection and analysis of listeners' emotions via facial expressions. By integrating these models with the Facial Emotion Recognition (FER) 2013, and The Extended Cohn-Kanade Dataset (CK+) dataset, our study aims to precisely identify a range of emotions including happiness, anger, sadness, surprise, disgust, and neutrality. In parallel, we employ Support Vector Machine (SVM) and Linear Discriminant Analysis (LDA) techniques to discern musical emotions from Spotify's dataset, encompassing moods such as happiness, sadness, energy, and calmness. A unique set of rules is formulated to amalgamate the insights from facial emotion recognition with musical emotion data, facilitating the automated suggestion of playlists that resonate with the user's current emotional state. Our experiments demonstrate notable results with the ResNet18 model achieved 72.67% accuracy and a 72.30% F1 score on the FER2013 dataset, with significant improvements on the CK+ dataset, reaching 96.97% accuracy and a 96.60% F1 score. The VGG19 model similarly excelled, particularly on the CK+ dataset with 95.96% accuracy and a 96.60% F1 score. On the FER2013 dataset, the VGG19 model achieved an accuracy of 72.64%, and an F1 score of 72.60%. Our music emotion recognition approach, using SVM on Spotify's dataset, achieved an 86.96% accuracy and an 84.54% F1 score. When using the LDA model on the same dataset, the accuracy was 79.00% and an F1 score of 76.72%. To bring this concept to fruition, we have developed an intuitive web application that allows users to capture their facial expressions via their device's camera, subsequently offering song recommendations tailored to their detected mood. [ABSTRACT FROM AUTHOR]

Background Children are especially vulnerable to Toxocara infection and its severe complications; however, there have not been any published data on the disease prevalence and treatment effectiveness in the population of Vietnamese children. This study was conducted to determine the prevalence of toxocariasis and explore factors associated with Toxocara infection in children aged 3–15 y in Ho Chi Minh City, Vietnam. Methods We conducted a cross-sectional study using a multistage cluster sampling approach in public schools. Blood samples were collected, and toxocariasis cases were confirmed, based on a history of contact with dogs/cats and positive anti- Toxocara antibody detection via ELISA. We calculated the percentage of seropositive children across gender, grade levels, districts and caregiver education. Multiple regression models were employed to identify potential risk factors. Results Anti- Toxocara antibodies were found in 14.2% of the 986 children studied. Significant variations in seropositivity were observed across grade levels, districts and caregiver education levels. Multivariable analysis identified caregiver education, contact with dogs/cats and improper handling of pet feces as seropositivity risk factors. Conclusion This was the first community-based prevalence study of toxocariasis in a pediatric population in Vietnam. Implementation of preventive measures such as public education, routine fecal examinations and chemotherapeutic treatment of animals is highly recommended. [ABSTRACT FROM AUTHOR]

This study describes a modified method to prepare nanomagnetic coated sugarcane bagasse. Under the general chemicals: iron (II) sulphate heptahydrate (FeSO4.7H2O); sodium hydroxide, hydrochloric acid, and iron (III) chloride hexahydrate (FeCl3.6H2O) these were commercially available and a simple method, authors were successfully synthesized Fe3O4 nanoparticles coated sugarcane bagasse. These nanoparticles were heterogenous and formed nanoclusters on the sugarcane bagasse surface under Scanning Electron Microscopy analysis. Herein, we show that given the right experimental circumstances, the novel and prospective nanomagnetic sugarcane bagasse might prove to be an intriguing adsorbent for a variety of applications. For tetracycline removal case study: the studied material was significantly adsorbed this contaminant with the highest adsorption capacity was 15 mg/g under 25 mg/L initial tetracycline concentration; pH 6; equilibrium time: 15 hours; and magnetic nanoparticle sugarcane bagasse: 1 g/L. The fundamental result in the research denotes that the material could be a potential adsorbent for eliminating various contaminants in upcoming studies.

The novel and facile multi-stage method was used for the conversion of bamboo into nanocellulose and single cell protein. Firstly, the bamboo chips were treated with sodium hydroxide solution followed by hydrogen peroxide bleaching for obtaining cellulose pulp with a brightness of 80% ISO. In the second stage, the obtained bleached cellulosic pulp was achieved with a dilute sulfuric acid and hydrogen peroxide followed by filtration for obtaining the sugar solution, which than was treated and used for Candida utilis cultivation, and nanocellulose, which than was submerged purification and refining for obtaining nanocellulose fibers. The optimal conditions of the yeast cultivation were dertermined for obtaining the single cell protein with protein content of approx. 49.5 wt.%. For isolation of nanocellulose with fiber diameter < 100 nm were proposed: concentration of hydrogen peroxide 0.25 wt.%, the concentration of sulfuric acid 0.75 wt. %, liquor to cellulose ratio 8 to 1, temperature 140oC, time 120 min. The characteristics of nanocellulose were studied by SEM, FTIR, and XRD.

Selective CO2 adsorption and catalysis conversion of CO2 to high value-added chemicals not only gives an effective way to reduce the concentration of CO2 but also provides the precursors for industrial manufacturing of chemicals and fuels. With well-defined frameworks, flexible modifiability, and permanent porosity, metal–organic frameworks (MOFs) can be the ideal platforms for CO2 utilization applications. In this work, a copper functionalized-zirconium MOF, denoted Zr-CPB-Cu (CPB = 1,2,3,4,5,6-hexakis(4-carboxyphenyl)-benzene), was successfully produced via post-metalation of copper(II) ions into a presynthesized Zr-CPB MOF. The bimetallic Zr-CPB-Cu containing two open metal sites (Zr4+ and Cu2+), polarized groups (e.g., uncoordinated –COOH, monodentate carboxylates, and acetate anions), accessible triangular channels, and permanent porosity (SBET = 420 m2 g−1) revealed outstanding selective CO2 adsorption and catalytic activity for the oxidative carboxylation of CO2 and olefins. As a proof of concept, the Zr-CPB-Cu showed higher low-pressure capacities of CO2, CH4, and N2 at room temperature and larger CO2 selectivities over N2 and CH4 than those of the parent Zr-CPB. As for catalysis of CO2 conversion, the Zr-CPB-Cu catalyst exhibited exceptional performance in direct synthesis of styrene carbonate from styrene and CO2 with 97% conversion of styrene, and 92% yield of styrene carbonate in the presence of anhydrous TBHP oxidant and under mild conditions (1 atm of CO2, 80 °C, and 12 h). Notably, the catalytic activity of Zr-CPB-Cu outperformed that of the parent Zr-CPB and other MOFs, and the recovered Zr-CPB-Cu can be reused up to six times without considerable reduction in catalytic activity. Our result envisaged an effective approach for the elaboration of MOFs as efficient heterogeneous catalysts for CO2 separation and catalytic conversion of CO2. [ABSTRACT FROM AUTHOR]

Selective CO2 adsorption and catalysis conversion of CO2 to high value-added chemicals not only gives an effective way to reduce the concentration of CO2 but also provides the precursors for industrial manufacturing of chemicals and fuels. With well-defined frameworks, flexible modifiability, and permanent porosity, metal–organic frameworks (MOFs) can be the ideal platforms for CO2 utilization applications. In this work, a copper functionalized-zirconium MOF, denoted Zr-CPB-Cu (CPB = 1,2,3,4,5,6-hexakis(4-carboxyphenyl)-benzene), was successfully produced via post-metalation of copper(II) ions into a presynthesized Zr-CPB MOF. The bimetallic Zr-CPB-Cu containing two open metal sites (Zr4+ and Cu2+), polarized groups (e.g., uncoordinated –COOH, monodentate carboxylates, and acetate anions), accessible triangular channels, and permanent porosity (SBET = 420 m2 g−1) revealed outstanding selective CO2 adsorption and catalytic activity for the oxidative carboxylation of CO2 and olefins. As a proof of concept, the Zr-CPB-Cu showed higher low-pressure capacities of CO2, CH4, and N2 at room temperature and larger CO2 selectivities over N2 and CH4 than those of the parent Zr-CPB. As for catalysis of CO2 conversion, the Zr-CPB-Cu catalyst exhibited exceptional performance in direct synthesis of styrene carbonate from styrene and CO2 with 97% conversion of styrene, and 92% yield of styrene carbonate in the presence of anhydrous TBHP oxidant and under mild conditions (1 atm of CO2, 80 °C, and 12 h). Notably, the catalytic activity of Zr-CPB-Cu outperformed that of the parent Zr-CPB and other MOFs, and the recovered Zr-CPB-Cu can be reused up to six times without considerable reduction in catalytic activity. Our result envisaged an effective approach for the elaboration of MOFs as efficient heterogeneous catalysts for CO2 separation and catalytic conversion of CO2. [ABSTRACT FROM AUTHOR]

Given the versatility of electronic properties induced by the synergic effect of metal-oxo clusters and multifunctional organic ligands, metal–organic frameworks (MOFs) have emerged as prospective materials for energy-related applications such as gas storage/separation and electrochemical storage. In this study, an iron-based MOF, namely, Fe-CPB (CPB = 1,2,3,4,5,6-hexakis(4-carboxyphenyl)benzene) was successfully synthesized via a solvothermal reaction and fully characterized. Taking advantage of the permanent porosity, the layered structure with high π-conjugation derived from a hexaphenylbenzene core, and polar carboxylate and acetate groups connected by infinite iron-oxo chains, Fe-CPB has been examined for its selective CO2 adsorption properties and electrochemical performance when applied as an anode material for lithium-ion batteries. As a proof-of-concept, Fe-CPB showed a moderate low-pressure CO2 uptake (40 cm3 g−1 at 273 K), high isosteric heat of CO2 adsorption (33 kJ mol−1), and good CO2 selectivity over N2 and CH4. As an anode material for rechargeable lithium-ion batteries, Fe-CPB exhibited a high reversible capacity of 634 mA h g−1 with 99% capacity retention after 100 cycles (at a current density of 100 mA g−1). Interestingly, Fe-CPB showed a high rate capability with a discharge capacity of 416 mA h g−1 (at a current density of 2000 mA g−1) and 673 mA h g−1 when the current density was returned to 100 mA g−1. Our result envisaged the potential of developing MOFs for energy applications including CO2 separation and electrodes of rechargeable batteries. [ABSTRACT FROM AUTHOR]

Novel therapeutics against the global threat of multidrug-resistant Neisseria gonorrhoeae are urgently needed. Gonococci evade killing by complement by binding factor H (FH), a key inhibitor of the alternative pathway. FH comprises 20 short consensus repeat (SCR) domains organized as a single chain. Gonococci bind FH through domains 6 and 7, and C-terminal domains 18 through 20. Previously, we showed that a chimeric protein comprising (from the N-to C-terminus) FH domains 18-20 (containing a point mutation in domain 19 to prevent lysis of host cells) fused to human IgG1 Fc (called FH*/Fc1) killed gonococci in a complement-dependent manner and reduced the duration and bacterial burden in the mouse vaginal colonization model of gonorrhea. Considering the N. gonorrhoeae-binding FH domains 18-20 are Cterminal in native FH, we reasoned that positioning Fc N-terminal to FH* (Fc1/FH*) would improve binding and bactericidal activity. Although both molecules bound gonococci similarly, Fc1/FH* displayed a 5-fold lower IC50 (the concentration required for 50% killing in complement-dependent bactericidal assays) than FH*/Fc1. To further increase complement activation, we replaced human IgG1 Fc in Fc1/FH* with Fc from human IgG3, the most potent complement-activating IgG subclass, to obtain Fc3/FH*. Bactericidal activity was further increased ~2.3-fold in Fc3/FH* compared to Fc1/FH*. Fc3/FH* killed (defined by <50% survival) 45/45 (100%) diverse PorB1B-expessing gonococci, but only 2/15 PorB1A-expressing isolates, in a complementdependent manner. Decreased Fc3/FH* binding accounted for the limited activity against PorB1A strains. Fc3/FH* was efficacious against all four tested PorB1B gonococcal strains in the mouse vaginal colonization model when administered at a dose of 5 µg intravaginally, daily. Furthermore, Fc3/FH* retained bactericidal activity when reconstituted following lyophilization orspray-drying, suggesting feasibility for formulation into intravaginal rings. In conclusion, Fc3/FH* represents a promising prophylactic immunotherapeutic against multidrug-resistant gonococci. [ABSTRACT FROM AUTHOR]