Addition Of Acid Research Articles

Environmental preferences of soil microbial attributes for long-term nitrogen and acid addition: From phylotype to community

The impact of human-induced nitrogen (N) enrichment on microbial diversity has been extensively studied, with two main hypotheses proposed: soil N availability and soil acidification. However, the specific roles of these two hypotheses and their environmental preferences on soil bacterial and fungal communities are not fully understood. By conducting two independent experiments (a 16-year N and a 6-year acid addition) in a temperate semi-arid grassland, we tested the responses of soil microbial attributes (e.g., richness and relative abundance) at various levels (community, phylum/class, and phylotype) to N and acid addition. At the community level, our results showed that both N and acid addition had a negative effect on the richness of the whole, dominant, and rare bacterial communities; N enrichment only decreased the richness of the dominant fungal community, while acid addition decreased the richness of the whole, dominant, and rare fungal communities. By categorizing the microbial attributes into nine environmental preferences based on their responses to N and acid addition, we found that most bacterial phyla were associated with low N availability and high pH preferences, while most fungal classes had other environmental preferences. Most dominant bacterial phylotypes were linked to low N availability and high pH preferences, while most dominant fungal phylotypes were associated with other environmental preferences and high pH preferences. Conversely, most rare bacterial and fungal phylotypes were linked to other environmental preferences. Our experiments revealed that the decline in bacterial richness caused by N enrichment was predominantly due to their sensitivity to soil acidification, while fungal richness remained largely unaltered. By pinpointing distinct microbial attributes at different levels in response to N and acid addition, our findings could potentially forecast how soil microorganisms will react to future global N deposition.

The comparison of mononuclear and binuclear nickel complexes in their synthesis and catalytic performance of styrene oxidation

The synthesis, characterization, and catalytic activity of four new nickel hydrazone complexes: [NiL2] (1), [Ni(HL)2]·2ClO4·3H2O (2), [Ni2L2(NCS)2(H2O)2]·2H2O (3) and [Ni2L2(NCNCN)2(CH3OH)2] (4) were reported here. HL was obtained by mixing 2-acetylpyridine, 2-aminobenzohydrazine, and methanol together. Complexes 1–4 were synthesized using HL and nickel perchlorate as the main raw materials, methanol as the solvent, and different auxiliary materials. The four complexes were characterized by FT-IR, UV–Vis, and 1H NMR, and their structures were further confirmed by X-ray single crystal diffraction. The impact of the four complexes on styrene oxidation was assessed by employing H2O2 as the oxidant. Investigations revealed that each complex demonstrated effective catalytic functions. Catalytic activity parameters, such as the ratio of substrate to oxidant, temperature, reaction time, catalyst dosage, solvent dosage, and solvent properties, as well as the effect of acid and base additives, were optimized to obtain better conversion of styrene. In particular, the different catalytic performance between mononuclear and binuclear nickel complexes was compared, and a possible mechanism was proposed.

Cu-Catalyzed Asymmetric Arylation of Enone Diesters with Arylboronic Acids.

The Cu-catalyzed asymmetric conjugate addition of arylboronic acids to enone diesters is reported. This operationally simple and scalable reaction proceeded under mild conditions. The practical utility of this approach was demonstrated by the synthesis of structurally important γ-lactones and a cyclopentene that bear an aryl group. Mechanistic studies revealed that two different copper catalytic species work synergistically in the reaction.

E-Cigarette Nicotine Delivery Among Young Adults by Nicotine Form, Concentration, and Flavor

Concerns have been raised about the abuse liability of modern e-cigarettes that use acidic additives to form nicotine salts, making the inhalation of nicotine smoother than freebase nicotine. To examine the effects of nicotine form and concentration and e-liquid flavor on subjective effects ratings, vaping behavior, and nicotine uptake among young adults who use e-cigarettes. In this single-blind, within-participant, crossover randomized clinical trial, a convenience sample of young adults aged 21 to 25 years who currently used e-cigarettes was recruited from December 2021 to August 2023, for in-person research laboratory visits in Columbus, Ohio. Participants completed up to 9 vaping sessions, starting with their usual e-cigarette brand in the first session followed by 1 of 8 laboratory-prepared e-liquids in a randomly assigned order in each subsequent session. Prepared e-liquids varied by nicotine form (salt-based vs freebase), nicotine concentration (5% vs 1% weight per weight), and flavor (menthol vs tobacco). Each session included a 5-minute, 10-puff standardized vaping period followed by 30 minutes of ad libitum vaping. At 4 time points (0, 5, 10, and 35 minutes) during each vaping session, plasma samples were collected for assessing nicotine uptake, and self-reports of urges, craving, and withdrawal were collected via questionnaires. Positive subjective effects were self-reported after 35 minutes of vaping using a visual analog scale; urges and cravings were reported using the Questionnaire of Smoking Urges (QSU). Puff topography data were collected throughout each vaping session. Seventy-two participants (mean [SD] age, 22.4 [1.4] years; 42 [58.3%] female) who sampled at least 1 laboratory-prepared e-liquid composed the analytic sample. Salt-based (vs freebase) nicotine e-liquids increased nicotine intake, with 5% salt-based e-liquids delivering the highest mean plasma levels of nicotine (11.2 ng/mL [95% CI, 9.3-13.2 ng/mL] at 5 minutes; 17.2 ng/mL [95% CI, 14.3-20.1 ng/mL] at 35 minutes) irrespective of flavors. Higher positive subjective effect ratings (eg, for liking) were received by salt-based (42.8; 95% CI, 39.4-46.1) vs freebase (32.0; 95% CI, 28.6-35.3) nicotine, 1% (43.4; 95% CI, 40.2-46.6) vs 5% (31.2; 95% CI, 27.7-34.6) nicotine, and menthol-flavored (43.2; 95% CI, 39.7-46.7) vs tobacco-flavored (31.5; 95% CI, 28.4-34.7) e-liquids. Salt-based and 1% but not menthol-flavored nicotine elicited more intense puffing (eg, 25% [95% CI, 12%-40%] more total puffs for nicotine salts vs freebase). All study e-liquids reduced urges and cravings, with 5% vs 1% nicotine being more effective (mean [SE] QSU-Desire score at 35 minutes, 15.4 [0.5] vs 16.7 [0.5]). In this crossover randomized clinical trial among young adult e-cigarette users, salt-based (vs freebase) nicotine e-liquids increased nicotine intake and yielded more positive subjective effects ratings and intense puffing behaviors, suggesting higher abuse potential. Restricting the level of acidic additives and menthol flavoring may reduce the addictiveness of e-cigarettes. ClinicalTrials.gov Identifier: NCT05458895.

γ-aminobutyric acid-assisted fabrication of plate-like ZSM-5 zeolite for efficient propylene production from methanol conversion

Plate-like ZSM-5 zeolites offering a short diffusion pathway along the b-axis are highly desirable catalyst for methanol to propylene (MTP) reaction. Herein, we successfully developed a simple synthetic strategy toward reducing the thickness along b-axis of ZSM-5 zeolite by combing a preliminary aging process and the addition of γ-aminobutyric acid. In particular, γ-aminobutyric acid adopted as a zeolite growth modifier was firstly proposed to prepare plate-like ZSM-5 zeolite with a short thickness of b-axis, and the minimum thickness can reach ∼50 nm. The shortened diffusion length in plate-like ZSM-5 zeolites could significantly improve the transport efficiency of molecules to and away from the active sites and finally leads to a better catalytic performance in the MTP reaction. Particularly, the plate-like ZSM-5 zeolite with an impressively shortened diffusion length (P-ZSM-5–0.3#0.3) displayed greatly improved catalytic performances (higher propylene selectivity and longer lifetime) than conventional ZSM-5 with a thicker dimension along the b-axis.

New functions of pirin proteins and a 2-ketoglutarate: Ferredoxin oxidoreductase ortholog in Bacteroides fragilis metabolism and their impact on antimicrobial susceptibility to metronidazole and amixicile.

The understanding of how central metabolism and fermentation pathways regulate antimicrobial susceptibility in the anaerobic pathogen Bacteroides fragilis is still incomplete. Our study reveals that B. fragilis encodes two iron-dependent, redox-sensitive regulatory pirin protein genes, pir1 and pir2. The mRNA expression of these genes increases when exposed to oxygen and during growth in iron-limiting conditions. These proteins, Pir1 and Pir2, influence the production of short-chain fatty acids and modify the susceptibility to metronidazole and amixicile, a new inhibitor of pyruvate: ferredoxin oxidoreductase in anaerobes. We have demonstrated that Pir1 and Pir2 interact directly with this oxidoreductase, as confirmed by two-hybrid system assays. Furthermore, structural analysis using AlphaFold2 predicts that Pir1 and Pir2 interact stably with several central metabolism enzymes, including the 2-ketoglutarate:ferredoxin oxidoreductases Kor1AB and Kor2CDAEBG. We used a series of metabolic mutants and electron transport chain inhibitors to demonstrate the extensive impact of bacterial metabolism on metronidazole and amixicile susceptibility. We also show that amixicile is an effective antimicrobial against B. fragilis in an experimental model of intra-abdominal infection. Our investigation led to the discovery that the kor2AEBG genes are essential for growth and have dual functions, including the formation of 2-ketoglutarate via the reverse TCA cycle. However, the metabolic activity that bypasses the function of Kor2AEBG following the addition of phospholipids or fatty acids remains undefined. Overall, our study provides new insights into the central metabolism of B. fragilis and its regulation by pirin proteins, which could be exploited for the development of new narrow-spectrum antimicrobials in the future.

Investigating the Effects of PU-Based Back-Coating with Boric Acid and Titanium Dioxide Additives on Flame Retardancy Levels and Comfort Properties of 100% Cotton Denim Fabric

Abstract This study aimed to develop a cost-effective and resource-efficient application to enhance the thermal stability, flame retardancy, self-cleaning, and antibacterial properties of cotton denim fabrics through a single-step, flexible, and simple polyurethane (PU) based back-coating method, ultimately increasing the use of denim fabrics in daily and work clothes thanks to the increased functionality. This method utilizes boric acid (H3BO3) and a binary composite of H3BO3-titanium dioxide (TiO2) as functional additives while considering comfort parameters. Limiting oxygen index (LOI) and vertical burning tests were conducted to explore the thermal stability and flame retardancy of the samples, while assessments of air permeability, water vapour permeability, thermal resistance, and thermal absorptivity were performed to investigate the comfort properties. Comparing two kinds of back-coated denim fabrics, H3BO3-TiO2 back-coated cotton fabric showed the best flame retardancy with the lowest char length (45 mm) and highest LOI (27%). The air permeability values of back-coated fabrics decreased by approximately half compared to the untreated denim fabric. Although the water vapour permeability values decreased, they were less affected by the coating. Coating application reduced thermal conductivity and thermal absorbency, resulting in more thermally resistant denim fabric. This study demonstrates the potential utility of a PU-based coating incorporating TiO2 and H3BO3 on traditional cotton denim fabrics to enhance flame resistance while minimizing any adverse effects on the overall thermal comfort of the fabric.

Enhancing growth rate in homoepitaxial growth of β-Ga2O3 with flat surface via hydrochloric acid addition in mist CVD

Gallium oxide (Ga2O3) is a wide-bandgap oxide semiconductor, with a bandgap of ∼4.9 eV, making it a promising material for power device applications. This study focuses on the effect of hydrochloric acid addition on the growth rate in homoepitaxial growth of β-Ga2O3 using a mist chemical vapor deposition method. For homoepitaxial growth on a (001) β-Ga2O3 substrate, we introduced different concentrations of HCl into the source solution to assess its impact on the growth rate, crystal structures, and surface morphologies of the films. At a growth temperature of 900 °C, HCl addition linearly increased film thickness, enhancing the growth rate by 4.8 times with 9.09 vol. % HCl. No peaks associated with other phases were exhibited by each sample, indicating pure homoepitaxial growth. When comparing samples with similar film thicknesses, the root-mean-square (rms) roughness was enhanced by 1/7 with an increase in the HCl concentration. However, at 800 °C, an increasing solution concentration caused pronounced step bunching and elevated rms roughness, in contrast with the minimal effect observed at 900 °C. In experiments with hydrochloric acid addition at 900 °C, we observed a striped morphology, which maintained consistent rms roughness despite higher temperature.

Engineering the TetR-family transcriptional regulator XNR_0706 to enhance heterologous spinosad production in Streptomyces albus B4 chassis

The TetR family of regulators are an important group of transcription regulators that regulate diverse cellular processes in prokaryotes. In this study, we found that XNR_0706, a TetR family regulator, controlled the expression of XNR_0345, XNR_0454, XNR_0513 and XNR_1438 putatively involved in fatty acid β-oxidation by interacting with the promoter regions in Streptomyces albus B4. The transcription level of these four genes was downregulated in XNR_0706 deletion strain (ΔXNR_0706) and restored by XNR_0706 complementation in Δ0706/pIB-0706, demonstrating that XNR_0706 was a positive transcriptional regulator of the genes. With toxic long-chain fatty acids addition in TSB media, deletion of XNR_0706 caused significantly poor growth, whereas XNR_0706 complementation increased the utilization of additional fatty acids, resulting in restored growth. Fatty acid β-oxidation is one source of acetyl- and malonyl-CoA precursors for polyketides biosynthesis in actinobacteria. Overexpression of XNR_0706 in B4/spnNEW, a spinosad heterologous expression strain derived from S. albus B4, increased spinosad yield by 20.6%. Additionally, supplement of 0.3 g/L fatty acids resulted in a further 42.4% increase in spinosad yield. Our study reveals a regulatory mechanism in long-chain fatty acids metabolism in S. albus and these insights into the molecular regulation of β-oxidation by XNR_0706 are instrumental for increasing secondary metabolites in actinobacteria.

Significance of zoledronic acid in the adjuvant therapy in patients with breast cancer

Introduction. Zoledronic acid is a medicine belonging to the bisphosphonate group. Its action is to inhibit the function of osteoclasts, which leads to a reduction in bone resorption. This preparation has a proven effect in the treatment of osteoporosis and Paget’s disease. Bisphosphonates have also found use in the treatment of breast cancer. Studies conducted for many years indicate that zoledronic acid works most favorably in combination with adjuvant therapy. Breast cancer patients who are postmenopausal and being treated with chemotherapy are at risk of bone mass loss and hypercalcemia. Bisphosphonates effectively manage this. In addition, zoledronic acid indirectly exerts anticancer effects by modulating the immune system. All this allows us to conclude that taking this drug reduces the risk of bone metastasis in breast cancer patients. Dosage is also key in all this. There are several regimens offered to osteoporosis and breast cancer patients. So far, the following have been studied: conventional dosing (4 mg IV every 3-4 weeks), maintenance dosing (4 mg IV every 3-6 months) and metronomic dosing (1 mg IV weekly). It cannot be ruled out that each of these regimens may have a different antitumor effect. By reviewing scientific works, we aim to present the treatment options with zoledronic acid for breast cancer patients. We will describe the impact on their results depending on the dosage and we will present the other side of the coin, which are the side effects of taking this preparation. Aim. This review provides an overview of the effects and impact of zoledronic acid in adjuvant therapy in patients with breast cancer. Material and methods. The article presents the current state of knowledge on zoledronic acid as an adjuvant treatment option in breast cancer patients. It is a detailed literature review using Google Scholar, PubMed and Journal of Education Health and Sport platforms. Publications using the following key words were analyzed: bisphosphonates, zoledronic acid, osteoporosis, breast cancer, bone metastases. Conclusion. Women diagnosed with breast cancer should be treated in a multidisciplinary manner. We treat early detected cancers to achieve complete remission. Long-term survival is our primary goal, and in pursuing it we should consider the potential impact of this treatment on the patient’s skeletal system. Clinical studies allow us to conclude that there is a correlation between the initiation of antiresorptive therapy at an early stage of cancer and overall survival. Additionally, zoledronic acid significantly reduced the number of fractures. The collected data allow us to conclude that the addition of zoledronic acid to the established treatment regimens has a potentially positive effect on the group of postmenopausal patients undergoing tamoxifen treatment or with existing bone metastases. Keywords: bisphosphonates, zoledronic acid, breast cancer, osteoporosis, bone metastases.

Biallelic null variants in PNPLA8 cause microcephaly by reducing the number of basal radial glia.

Patatin-like phospholipase domain-containing lipase 8 (PNPLA8), one of the calcium-independent phospholipase A2 enzymes, is involved in various physiological processes through the maintenance of membrane phospholipids. Biallelic variants in PNPLA8 have been associated with a range of paediatric neurodegenerative disorders. However, the phenotypic spectrum, genotype-phenotype correlations and the underlying mechanisms are poorly understood. Here, we newly identified 14 individuals from 12 unrelated families with biallelic ultra-rare variants in PNPLA8 presenting with a wide phenotypic spectrum of clinical features. Analysis of the clinical features of current and previously reported individuals (25 affected individuals across 20 families) showed that PNPLA8-related neurological diseases manifest as a continuum ranging from variable developmental and/or degenerative epileptic-dyskinetic encephalopathy to childhood-onset neurodegeneration. We found that complete loss of PNPLA8 was associated with the more profound end of the spectrum, with congenital microcephaly. Using cerebral organoids generated from human induced pluripotent stem cells, we found that loss of PNPLA8 led to developmental defects by reducing the number of basal radial glial cells and upper-layer neurons. Spatial transcriptomics revealed that loss of PNPLA8 altered the fate specification of apical radial glial cells, as reflected by the enrichment of gene sets related to the cell cycle, basal radial glial cells and neural differentiation. Neural progenitor cells lacking PNPLA8 showed a reduced amount of lysophosphatidic acid, lysophosphatidylethanolamine and phosphatidic acid. The reduced number of basal radial glial cells in patient-derived cerebral organoids was rescued, in part, by the addition of lysophosphatidic acid. Our data suggest that PNPLA8 is crucial to meet phospholipid synthetic needs and to produce abundant basal radial glial cells in human brain development.

Effect of Dietary Lysine and DL-Methionine Supplementation in Roasted Soyabean-Based Diet on the Growth Performance and Blood Profiles of Clarias gariepinus

This study was designed to investigating the growth performance, hematology, and serum biochemistry of Clarias gariepinus nourished with roasted soyabean based diets with varied inclusion of dietary amino acid. A total of 360 Clarias gariepinus juveniles, aged eight weeks and weighing 19.0±0.4 grams, were randomly assigned to six different diets with varying inclusion levels of lysine and DL-methionine (g/100g). The diets were as follows: RS1 (Control) without lysine or DL-methionine supplementation; RS 2 - 0g + 1g; RS 3 - 0.25g + 0.75g; RS 4 - 0.5g + 0.5g; RS 5 - 0.75g + 0.25g; and RS 6 - 1g + 0g of Lysine and DL-methionine. For 84 days, the fish were fed until they were completely satisfied. Each treatment was in triplicate. Supplementing lysine and methionine in a diet based on roasted soybeans did not significantly (P>0.05) effect on the growth parameter such as final weight, feed conversion ratio, and/or specific growth rate in fish. A significantly higher survival rate was observed in fish on diet RS 5 (85.60±0.60) and was closely followed by fish fed diet RS 3 and RS 4. Fish fed diets RS 4 and RS 5 exhibited significantly higher (P<0.05) packed cell volume (PCV %) and hemoglobin levels. While, White blood cell counts (x10^9/L) varied significantly among the different diets. The addition of supplemental amino acids did not significantly (P>0.05) affect total protein (g/L), and the values ranges from 6.60±0.52 (RS 6) to 7.87±0.55 (RS 4). This study showed that supplementation of lysine and DL-methionine in Roasted Soyabean based diet could improve growth performance of fish with no adverse effect on fish health.

Modulating Helix-Preference of an Axially-Twisted Molecular Scaffold Through Diastereomeric Salt Formation with Tartaric Acid Stereoisomers.

Herein, we designed a chiral, axially-twisted molecular scaffold (ATMS) using pyridine-2,6-dicarboxamide (PDC) unit as pivot, chiral trans-cyclohexanediamine (CHDA) residues as linkers, and pyrene residues as fluorescent reporters. R,R-ATMS exclusively adopted M-helicity and produced differential response in UV-vis, fluorescence, and NMR upon addition of tartaric acid (TA) stereoisomers allowing naked-eye detection and enantiomeric content determination. Circular dichroism (CD) profile of R,R-ATMS underwent unique changes during titration with TA stereoisomers - while loss of CD signal at 345 nm was observed with equimolar D-TA and meso-TA, inversion was seen with equimolar L-TA. Temperature increase weakened these interactions to partially recover the original CD signature of R,R-ATMS. 2D NMR studies also indicated the significant structural changes in R,R-ATMS in the solution state upon addition of L-TA. Single crystal X-ray diffraction (SCXRD) studies on the crystals of the R,R-ATMS⊃D-TA salt revealed the interacting partners stacked in arrays and ATMS molecules stabilized by π-π stacking between its PDC and pyrene residues. Contrastingly, tightly-packed supramolecular cages comprised of four molecules each of R,R-ATMS and L-TA were seen in R,R-ATMS⊃L-TA salt, and the ATMS molecules contorted to achieve CH-π interactions between its pyrene residues. These results may have implications in modulating the helicity of topologically-similar larger biomolecules.

Long-term Effect of Sodic Water for Irrigation on Soil Quality and Wheat Yield in Rice-Wheat Cropping System

Increasing scarcity of good quality water in many arid and semi-arid regions necessitates the use of poor quality groundwater for irrigation. Soil degradation resulting from alkali water irrigation has become a serious threat to soil health. In the present study, we conducted an investigation (2021-22) on the physicochemical properties (soil organic carbon, available Na, and available K) of sandy loam soil under a semi-controlled lysimeter. Wheat was grown as an experimental crop, which was irrigated with synthetic alkali waters having similar salts (total electrolyte concentration, TEC = 30 me L−1) and sodium adsorption ratio (SARiw 10 mmol L−1) but varying in residual sodium carbonate (RSC) are being continuously applied since 2004 (20 years). Five types of irrigation water having different levels of residual sodium carbonate comprised. (T1) best available groundwater, (T2) residual sodium carbonate water 1 (RSC- 5 me L–1), (T3) RSC water 2 (RSC 10 me L–1), (T4) RSC water 3 [RSC 10 treated with gypsum (RSC 10 neutralized to RSC 5 me L–1 with gypsum)] and (T5) RSC water 4 [RSC 10 treated with sulphur (RSC 10 neutralized to RSC 5 me L–1 with sulphur)]. Soil samples were collected after harvesting two wheat varieties (KRL 210 and HD 3226). Long-term irrigations with alkali water increased the available Na and K in the soil. Furthermore, soil organic carbon (SOC) decreased significantly with increasing alkalinity of irrigation water. Continuous irrigation with alkali water reduced grain yield of wheat by 31.7% over BAW. Moreover, the addition of gypsum and sulphuric acid has shown some capacity to partially restore soil properties, although not to the level of BAW. The majority of soil parameters under both crop cultivars showed a similar trend. The study's findings led to the conclusion that continuous applications of alkali water drastically degrade soil physicochemical properties. Partial neutralization of alkali water did not allow for the sustained existence of soil physicochemical properties. Consequently, it is recommended that the rate at which amendments are added to alkali water be adjusted to restore the decline in soil physicochemical properties.

Determination of Nicotine Protonation State in E-Liquids by Low-Resolution Benchtop NMR Spectroscopy.

Over several years, e-liquids with "nicotine salts" have gained considerable popularity. These e-liquids have a low pH, at which nicotine occurs mostly in its monoprotonated form. Manufacturers usually accomplish this by the addition of an organic acid, such as levulinic acid, benzoic acid, or lactic acid. Nicotine in its protonated form can be more easily inhaled, enhancing the addictiveness and attractiveness of products. Several techniques have been described for measuring the protonation state of nicotine in e-liquids. However, nuclear magnetic resonance (NMR) spectroscopy is particularly suited for this purpose because it can be performed on unaltered e-liquids. In this article, we demonstrate the suitability of a benchtop NMR (60 MHz) instrument for determining the protonation state of nicotine in e-liquids. The method is subsequently applied to measure the protonation state of 33 commercially available e-liquids and to investigate whether the vaping process alters the protonation state of nicotine. For this purpose, the protonation state in the condensed aerosol obtained by automated vaping of different e-liquids was compared with that of the original e-liquids. Two distinct populations were observed in the protonation state of nicotine in commercial e-liquids: free-base (fraction of free-base nicotine αfb > 0.80) and protonated (αfb < 0.40). For 30 e-liquids out of 33, the information on the packaging regarding the presence of nicotine salt was in agreement with the observed protonation state. Three e-liquids contained nicotine salt, even though this was not stated on the packaging. Measuring the protonation state of nicotine before and after (machine) vaping revealed that the protonation state of e-liquids is not affected by vaping. In conclusion, it is possible to determine the nicotine protonation state with the described method. Two clusters can be distinguished in the protonation state of commercial e-liquids, and the protonation state of nicotine remains unchanged after vaping.

Modulating Weak Protein-Protein Cross-Interactions by the Addition of Free Amino Acids at Millimolar Concentrations.

In this paper, we quantify weak protein-protein interactions in solution using cross-interaction chromatography (CIC) and surface plasmon resonance (SPR) and demonstrate that they can be modulated by the addition of millimolar concentrations of free amino acids. With CIC, we determined the second osmotic virial cross-interaction coefficient (B23) as a proxy for the interaction strength between two different proteins. We perform SPR experiments to establish the binding affinity between the same proteins. With CIC, we show that the amino acids proline, glutamine, and arginine render the protein cross-interactions more repulsive or equivalently less attractive. Specifically, we measured B23 between lysozyme (Lys) and bovine serum albumin (BSA) and between Lys and protein isolates (whey and canola). We find that B23 increases when amino acids are added to the solution even at millimolar concentrations, corresponding to protein/ligand stoichiometric ratios as low as 1:1. With SPR, we show that the binding affinity between proteins can change by 1 order of magnitude when 10 mM glutamine is added. In the case of Lys and one whey protein isolate (WPI), it changes from the mM to the M range, thus by 3 orders of magnitude. Interestingly, this efficient modulation of the protein cross-interactions does not alter the protein's secondary structure. The capacity of amino acids to modulate protein cross-interactions at mM concentrations is remarkable and may have an impact across fields in particular for specific applications in the food or pharmaceutical industries.

Effects of sodium ions on the tribological and antioxidation properties of borates

A borate ester (BMBS) and its sodium salts (BMBSNa) were synthesized and used as multifunctional lubricant additives in oleic acid. Results showed that BMBSNa possessed better anti-oxidation and tribological properties than BMBS. Worn surfaces analysis revealed that BMBSNa was more favorable to forming boundary film containing h-BN and FeS. Theoretical calculation suggested that BMBSNa had a higher chemical reactivity and better metal adsorption ability than BMBS. Fukui indices showed that sodium ions favor free radical reaction. Radial distribution functions (RDF) indicated that sodium ions help the adsorption of BMBSNa on the iron surface. It can be concluded that sodium ions benefit the oxidation resistance of base oil, and contribute to forming good boundary lubrication film to achieve good tribological properties.

Humic Acids Combined with Dairy Slurry as Fertilizer Can Increase Alfalfa Yield and Reduce Nitrogen Losses

Dairy slurry could be a significant source of nitrogen (N) for plants, but mismanagement can lead to atmospheric ammonia losses or nitrate leaching into groundwater. To make the use of dairy slurry efficient and reasonable, the loss of N pollution to the environment should be reduced. We used repacked lysimeters to comprehensively determine ammonia emission and N leaching losses in an alfalfa–soil system. The application of dairy slurry had no significant effect on alfalfa yield at the same rate of N application in comparison to chemical fertilizer, and adding humic acids significantly increased yield by about 12%. However, the application of dairy slurry increased the ammonia emission rate significantly, leading to an increase in the cumulative amount of ammonia emission, while the addition of humic acids reduced the ammonia emissions by 11%. Chemical fertilizer and dairy slurry application significantly increased nitrate leaching compared to the control treatment, while the addition of humic acids can significantly reduce ammonium N leaching. Dairy slurry was proven to be as effective as chemical N fertilizer in achieving the optimum biomass, and adding humic acids can significantly reduce N loss to the atmosphere and groundwater. This study showed the possibility of replacing chemical fertilizer with dairy slurry in alfalfa production and the advantages of humic acids’ addition to alfalfa to maintain production yield and improve environmental friendliness.

Ascorbic acid as serine protease inhibitor in lung cancer cell line and human serum albumin.

Serine proteases (SPs) are distributed among all living cells accounting for almost one-third of all proteases. Dysregulation of SPs during inflammation and/or infection can result in devastating consequences, such as skin and lung inflammation, neuroinflammation, arthritis, as well as metastasis of cancerous cells. Such activities are tightly regulated by various inhibitors known as serine protease inhibitors (SERPIN). The thermodynamic investigations previously revealed that L-ascorbic acid binds to trypsin more firmly than pepsin and the binding force of L-ascorbic acid is driven by hydrogen bonds and van der Waals forces. However, the physiochemical effects of such interaction on trypsin and/or pepsin have not yet been reported. Ascorbic acid, also known as vitamin C, is one of the essential nutrients and most common food supplements, fortificants, and preservatives. The aim of this study was to explore the inhibitory effects of ascorbic acid on serine proteases at various concentrations on the in-vitro digestion and/or hydrolysis of intercellular matrix of cell monolayer and human serum albumin (HSA). The inhibitory effects of ascorbic on trypsin are investigated by qualitative and quantitative analysis using SDS-PAGE imaging and NIH densitometric software. Upon the addition of ascorbic acid in both indicator systems, the detachment and/or dissociation of cell monolayer and the digestion of HSA were inhibited in the presence of EDTA-Trypsin. The inhibitory effect of ascorbic acid on the digestion of intercellular matrix and/or hydrolysis of HSA showed a dose-dependent trend until it reached the maximum extent of inhibition. At an equal concentration (2.5mg/mL) ascorbic acid and EDTA-Trypsin exhibited the most potent inhibitory effect on the in vitro digestion of protein either in the form of intercellular matrix in cell monolayer and/or HSA respectively. Overall, our results based on two indicator systems strongly indicate that ascorbic acid may function as a serine protease inhibitor (SERPIN) beyond other important functions.

Enhanced optoelectrical properties and stability of solvent-based perovskite solar cells using ellagic acid additives

Perovskite solar cells (PSCs) with solution-based fabrication processes deserve a simple and controllable fabrication process to produce cost-effective new-generation solar cells. Increasing optoelectrical properties of the light-harvesting perovskite layer during the fabrication process is used to enhance photovoltaic efficiency and the stability of PSCs. Here, ellagic acid was added into the lead iodide precursor to control the reaction of lead iodide with formamidinium iodide to generate a perovskite layer with enlarged grains. The obtained results showed the ellagic acid additive reduced charge recombination losses within solar cells and prompted charge transfer from perovskite to electron transporting layer and hole transporting layer, recording a champion efficiency of 22.04 % along with an open circuit voltage of 1.095 V, short-circuit current density of 24.17 mA cm−2, and fill factor of 78.94 %. In addition, the ellagic acid-based PSCs showed considerable stability improvement against the humidity and light irradiance compared to the control PSCs. It can be concluded that the ellagic acid additive may push the PSCs further to commercialization.