Normal pH Research Articles

Magnetization Study of Iron Sand from Sabang, Indonesia: The Potential of Magnetic Materials in the Photocatalytic Field

The magnetization of iron sand from Anoi Itam beach, Sabang, Indonesia, was investigated through sample testing and synthesis using the co-precipitation method. The purpose of this study is to analyze the magnetic properties of iron sand and review its potential in photocatalytic processes. Before being synthesized, the natural iron sand was separated and milled. The iron sand was dissolved in 37% v/v HCl, stirred, and heated for 30 min. This solution was filtered and precipitated with 6.5 M NH4OH while stirring and heating for 30 min. The magnetite formed was washed repeatedly with distilled water until it reached a normal pH, and then dried. Magnetite characterization tests were performed using XRF, XRD, VSM, and UV-Vis spectroscopy. The test results showed that the iron sand had a high magnetic quality with a concentration of 91.17% after the synthesis process. The resulting magnetite phase structure had a spinal inverse cubic shape, with the highest peak at the Miller index (311). From the VSM test, it is known that the resulting magnetite exists in a soft magnetic form with superparamagnetic groups. From optical absorption, magnetite has a gap energy of approximately 2.8 eV. It can be concluded that the magnetite from Anoi Itam Sabang has potential as a photocatalytic absorbent in the visible light wavelength region. Copyright © 2023 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Umbilical cord gas analysis: clinical implications of a comprehensive, contemporary determination of normal ranges

Umbilical cord gases are often used to assess the impact of labor and delivery on the fetus. However, no large series exists that reflects contemporary obstetrical practice or that analyzed blood gas ranges by route of delivery. Baseline, prelabor acid-base status in the human fetus is also poorly defined, rendering the assessment of blood gas changes during labor difficult. This study aimed to define normal umbilical cord gas and lactate values, stratified by mode of delivery, in a large contemporary series in which universal umbilical cord gas evaluation was dictated by protocol. This was a retrospective cohort study. We analyzed the umbilical cord gas and lactate data of an unselected population of infants born between March 2012 and April 2022 at a large teaching hospital. These values were then analyzed by mode of delivery and, for cesarean deliveries, by indication for cesarean delivery and type of anesthesia. Umbilical cord gas values from infants delivered by elective cesarean delivey under general anesthesia without labor were considered representative of baseline, prelabor values. Data were available for 45,475 infants. The median arterial pH values and interquartile ranges for vaginal births, elective cesarean deliveries without labor, and cesarean deliveries performed for fetal heart rate concerns were 7.27 (0.09), 7.27 (0.06), and 7.25 (0.09), respectively. Arterial lactate values for these same 3 groups were 4.1 (2.5), 2.5 (1.2), and 4.0 (2.8) mmoles/L, respectively. Because of the very large sample size, most comparisons yielded differences that were statistically significant, but clinically irrelevant. Of all the infants, 14% had an arterial pH <7.20; a pH value of 7.1 represents 2 standard deviations from the mean. This large, population-based study of umbilical cord gas and lactate levels in an unselected population, stratified by delivery mode, represents a previously unavailable benchmark for the evaluation of umbilical cord gases. Arterial umbilical cord pH values for infants delivered by elective caesarean delivery without labor (median pH 7.28) reflect a lower prelabor fetal pH baseline than previously assumed. This finding, coupled with our determination that a 2 standard deviation below normal pH limit of 7.1, instead of the historic arbitrary pH of 7.2 threshold, helps to explain the poor positive predictive value of electronic fetal heart rate monitoring, a test designed to detect arterial pH levels that have fallen from an assumed baseline near pH 7.4 to an assumed potentially injurious pH level of <7.2. Uncomplicated labor, even when prolonged, does not generally lead to a clinically significant cumulative hypoxic stress to the human fetus. These findings, along with our determination that there is no difference in the acid-base status among infants delivered by cesarean delivery for fetal heart rate concerns, help to explain the failure of current approaches in labor and delivery management to reduce the rates of neonatal hypoxic-ischemic encephalopathy and cerebral palsy, conditions that almost always reflect developmental events rather than the effects of labor on the fetus.

Assessment ofurinary 6-hydroxy-2,4-cyclohexadienyl mercapturic acid as a novel biomarker ofbenzene exposure.

Assessing benzene exposure is a public health priority due to its deleterious health effects and ubiquitous industrial and environmental sources of exposure. Phenyl mercapturic acid (PhMA) is a commonly used urinary biomarker to assess benzene exposure. However, recent work has identified significant interlaboratory variation in urinary PhMA concentrations related to methodological differences. In this study, we present urinary 6-hydroxy-2,4-cyclohexadienyl mercapturic acid (pre-PhMA), a metabolite that undergoes acid-catalyzed dehydration to form PhMA, as a novel and specific urinary biomarker for assessing benzene exposure. We developed and validated the first quantitative liquid chromatography-tandem mass spectrometry assay for measuring urinary concentrations of pre-PhMA. The pH effect on the method of ruggedness testing determined that pre-PhMA is stable across the normal human urine pH range and that neutral conditions must be maintained throughout quantification for robust and accurate measurement of urinary pre-PhMA concentrations. The method exhibited below 2 ng/mL sensitivity for pre-PhMA, linearity over three orders of magnitude, and precision and accuracy within 10%. Urinary pre-PhMA concentrations were assessed in 369 human urine samples. Smoking individuals exhibited elevated levels of pre-PhMA compared to non-smoking individuals. Furthermore, the relationship between benzene exposure and urinary pre-PhMA levels was explored by examining the correlation of pre-PhMA with 2-cyanoethyl mercapturic acid, a smoke exposure biomarker. The urinary biomarkers exhibited a positive correlation (r = 0.720), indicating that pre-PhMA levels increased with benzene exposure. The results of this study demonstrate that urinary pre-PhMA is a rugged and effective novel biomarker of benzene exposure that can be widely implemented for future biomonitoring studies.

Facile preparation of dual functions zeolite‐carbon composite for zinc ion removal from aqueous solutions

AbstractThe cost‐effective dual functions zeolite‐carbon composite (DFZCC) was prepared using an eco‐friendly substrate prepared from bio‐waste and an organic adhesive at intermediate conditions. The green synthesis method used in this study ensures that chemically harmless compounds are used to obtain a homogeneous distribution of zeolite over porous carbon. The greenly prepared dual‐function composite was extensively characterized using Fourier transform infrared, X‐ray diffraction, thermogravimetric analysis, N2 adsorption/desorption isotherms, field emission scanning electron microscope, dispersive analysis by X‐ray, and point of zero charges. DFZCC had a surface area of 248.84 m2/g and a pore volume of 0.141 cm3/g. DFZCC was used in the sorption process of Zn2+ ions from aqueous solutions, and it achieved higher removal (98%) at normal pH of 6.4 and temperature of 40°C. The Langmuir model was the best model for representing equilibrium data with a maximum sorption capacity of 6.711 mg/g. The kinetic studies showed that the pseudo‐second‐order model was the most appropriate model for representing experimental data. The intra‐particle diffusion kinetics demonstrated that the boundary film is the rate‐determining step in the sorption process. The sorption process of Zn2+ ions by DFZCC was spontaneous and endothermic. Moreover, solidification of the spent DFZCC by kaolin successfully reduced the leaching ions to the solution after 12 weeks from exposure to a salty solution.

Novel polysaccharide-derived carbon dots doped with N, S, P: Synthesis, characterization, in vitro antioxidant, fluorescence sensor for chromium (VI) detection and cellular imaging

In this work, for the first time, biomass-derived carbon dots (AMP-CDs) with strong water solubility, antioxidant activity and good biocompatibility were synthesized by a one-step microwave method using Allium macrostemon Bunge polysaccharides (AMP) as the main carbon source, L-cysteine as the nitrogen and sulfur source, and phosphoric acid as the phosphorus source. The results showed that sphere-like AMP-CDs with an average particle size of about 2.34 ± 0.49 nm were successfully prepared, with good resistance to salt and photobleaching, and maintained high fluorescence intensity under normal pH conditions in human body. AMP-CDs were highly resistant to 2,2-diphenyl-1-pycrylhydrazyl (DPPH), 2,2′-Azinobis- (3-ethylbenzthiazoline-6-sulphonate) (ABTS) and hydroxyl radical (·OH) with significantly higher scavenging ability than AMP, with IC50 (μg/mL) of 10.240, 7.265, and 574.730, respectively. In addition, AMP-CDs can be selectively used for the sensitive detection of Cr6+ with the limit of detection was 5.25 μM, and satisfactory results were obtained for the Cr6+ recovery experiments of actual environmental samples. In vitro cytotoxicity and hemolytic activity assays showed that AMP-CDs have good biocompatibility and can smoothly enter cells for clear imaging. Therefore, AMP-CDs are likely expected to be applied as a potential antioxidant and metal ion detection probe in the field of drug and food, environmental and biological scenario samples for metal ion detection analysis.

Stage-controlled antibacterial surgical sutures based on curcumin@ZIF-8 functional coating for improved wound healing

Antibacterial surgical sutures play a significant role in preventing incision infections and promoting wound healing. However, the existing antibacterial sutures failed to match well with staged antibacterial requirements during wound healing progress. Herein, to endow the sutures with stage-controlled antibacterial properties, a simple and feasible strategy of decorating the suture surface with curcumin@zeolitic imidazolate framework-8 (Cur@ZIF-8) was proposed. The pH of the microenvironment changes during the wound healing process, which declines to acidic in the early postoperative stage due to the aseptic/bacterial inflammatory infection and returns to normal with wound healing. Coincidentally, benefiting from the pH-responsive behavior of ZIF-8, Zn2+ and Cur could be quickly released under an acidic environment, facilitating bacteria-killing efficiency and preventing surgical site infections timely. The release amount of Zn2+ and Cur decreased under a normal pH environment, protecting the cells/tissues from damage caused by their excessive release. In addition, in vitro and in vivo studies revealed that the developed functional sutures could enhance wound healing, as evidenced by stage-controlled release behavior, good antibacterial activity, reduced inflammatory reaction, re-epithelization, and collagen regeneration. Furthermore, thanks to the gentle preparation process, the original mechanical property and handling performance of the sutures were preserved, guaranteeing their practical clinical availability.

Effect of consuming young coconut water (Cocos nucifera) on saliva pH levels in the oral cavity

including lubrication, fluid balance, prevention of pathogenic bacteria, and maintenance of oral pH to prevent cavities. The balance between acidity and alkalinity in saliva is very important for the function of the oral cavity, with a normal pH range of 6.8 to 7.0. In Indonesia, young coconut water is a drink that is often consumed and easily available with a pH of around 5.5, containing potassium, sodium, calcium, vitamin C, and reducing sugars. Purpose: This study aims to determine the impact of consuming young coconut water (Cocos Nucifera) on the pH level of saliva in the oral cavity. Methods: This research is pre-experimental with pretest and posttest design. The research sample consisted of 30 dental students from the Faculty of Dentistry, Institute of Health Sciences Bhakti Wiyata Kediri in 2019, 2020, 2021 and 2022, who met the sample criteria. Results: Data were analyzed using the parametric Paired T-Test hypothesis test, with a significance value of 0.000. Conclusion: Young coconut water consumption has an impact on changes in the salivary pH level in the oral cavity.

Extended Wireless pH Monitoring Significantly Increases Gastroesophageal Reflux Disease Diagnoses in Patients With a Normal pH Impedance Study.

Extended wireless pH monitoring (WPM) is used to investigate gastroesophageal reflux disease (GERD) as subsequent or alternative investigation to 24-hour catheter-based studies. However, false negative catheter studies may occur in patients with intermittent reflux or due to catheter-induced discomfort or altered behavior. We aim to investigate the diagnostic yield of WPM after a negative 24-hour multichannel intraluminal impedance pH (MII-pH) monitoring study and to determine predictors of GERD on WPM given a negative MII-pH. Consecutive adult patients (> 18 years) who underwent WPM for further investigation of suspected GERD following a negative 24-hour MII-pH and upper endoscopy between January 2010 and December 2019 were retrospectively included. Clinical data, endoscopy, MII-pH, and WPM results were retrieved. Fisher's exact test, Wilcoxon rank sum test, or Student's t test were used to compare data. Logistic regression analysis was used to investigate predictors of positive WMP. One hundred and eighty-one consecutive patients underwent WPM following a negative MII-pH study. On average and worst day analysis, 33.7% (61/181) and 34.2% (62/181) of the patients negative for GERD on MII-pH were given a diagnosis of GERD following WPM, respectively. On a stepwise multiple logistic regression analysis, the basal respiratory minimum pressure of the lower esophageal sphincter was a significant predictor of GERD with OR = 0.95 (0.90-1.00, P = 0.041). WPM increases GERD diagnostic yield in patients with a negative MII-pH selected for further testing based on clinical suspicion. Further studies are needed to assess the role of WPM as a first line investigation in patients with GERD symptoms.

PH‐dependent swellable hyaluronate nanogels targeting acidic tumors

AbstractIn this study, we have developed pH‐dependent nanogels based on hyaluronic acid (HA) to specifically target acidic tumors. Our initial approach involved modifying HA through the grafting of 3‐(diethylamino)propylamine (DEAP), a molecule known for its responsiveness to changes in pH. This modified HA was termed as HDEA. Subsequently, we performed chemical crosslinking of HDEA using adipic acid dihydrazide (ADH), a crosslinking molecule, resulting in the formation of nanogels referred to as cHDEA. Importantly, the non‐ionized DEAP molecules (with a pKb value of ~pH 7.0) at pH 7.4 support the formation of deswellable cHDEA. This property enables the encapsulation of a photodynamic model drug, chlorin e6 (Ce6), into cHDEA. However, when the DEAP molecules become protonated at pH 6.8, they induce a change in the nanogel structure, causing it to swell due to electrostatic repulsion. As a result, Ce6 is rapidly released from the nanogels. By modulating the pH, we can continuously control the nanogel structure, alternating between swelling and deswelling states. We anticipate that this system offers the advantage of facilitating drug release specifically under acidic tumor conditions while inhibiting drug release under normal pH conditions (i.e., pH 7.4). This approach will serve as an effective strategy for mitigating side effects by efficiently controlling drug release in specific disease areas.

Influencia del pH de cordón umbilical en el resultado del cribado auditivo con otoemisiones en recién nacidos sanos

ObjectiveThe effect of hypoxia on the functioning of the outer hair cells of the cochlea, which are responsible for the response to otoemissions used in neonatal hearing screening, is well known.The aim of this study is to determine the influence of mild to moderate variations in umbilical cord pH at birth on the outcome of hearing screening with otoemissions in healthy newborns without hearing risk factors. ResultsThe sample is composed of 4536 healthy infants. The results show no significant differences in the hearing screening outcome between the asphyctic (<7.20) and normal pH group. Nor is a figure below 7.20 detected in the sample that is related to an alteration in the screening.When broken down into subgroups with known factors of variation in the screening result, such as gender or lactation, no significant differences in response were detected.Apgar ≤ 7 is significantly related to pH<7.20. ConclusionsIn conclusion, mild-moderate asphyxia associated with delivery of healthy newborns, without auditory risk factors, does not alter the outcome of otoemission screening.

A temperature-responsive drug release system based on MoS2 nanosheets and 1-tetradecanol

The high specific surface area and photothermal ability of 2D MoS2 nanostructures have attracted a lot of attention in combined photo-chemotherapy. In this research, we synthesized PEGylated MoS2 with dispersed nanosheet morphology through a simple hydrothermal method and loaded them with Doxorubicin (DOX) as an anticancer drug (MoS2-PEG/DOX). Synthesized MoS2 nanosheets demonstrate a high drug loading capacity (DLC) of 122.2%. This is the first report of the high DLC for MoS2-PEG nanosheets synthesized with the hydrothermal method. To prevent premature drug release and increase DLC to 184%, MoS2-PEG/DOX is coated with 1-tetradecanol (TD) which is a bio-compatible temperature-responsive material (MoS2-PEG/DOX@TD). The prepared nanostructure is a dual-responsive platform that drug release can be controlled by pH and NIR irradiation. The release profile was investigated and compared at normal and acidic pH and three different conditions for each pH (body temperature, ambient mild hyperthermia temperature, and NIR irradiation). The results indicate that the most amount of DOX is released in acidic pH and hyperthermia temperature (43 ℃). NIR irradiation has an extensive effect on DOX release in comparison with hyperthermia temperature so 34.75% of the drug is released within only 30 min of laser irradiation with a power density of 1 W/cm2 in acidic pH. MTT results indicate that this nanoplatform is biocompatible. Hence dispersed MoS2-PEG nanosheets with high DLC, coated with TD for the first time, can improve the efficiency of synergistic photo-chemotherapy and can solve the problem of premature drug release from MoS2 nanosheets and release drug under controlled conditions.

Role of the kidneys in acid-base regulation and ammonia excretion in freshwater and seawater fish: implications for nephrocalcinosis.

Maintaining normal pH levels in the body fluids is essential for homeostasis and represents one of the most tightly regulated physiological processes among vertebrates. Fish are generally ammoniotelic and inhabit diverse aquatic environments that present many respiratory, acidifying, alkalinizing, ionic and osmotic stressors to which they are able to adapt. They have evolved flexible strategies for the regulation of acid-base equivalents (H+, NH4 +, OH- and HCO3 -), ammonia and phosphate to cope with these stressors. The gills are the main regulatory organ, while the kidneys play an important, often overlooked accessory role in acid-base regulation. Here we outline the kidneys role in regulation of acid-base equivalents and two of the key 'urinary buffers', ammonia and phosphate, by integrating known aspects of renal physiology with recent advances in the molecular and cellular physiology of membrane transport systems in the teleost kidneys. The renal transporters (NHE3, NBC1, AE1, SLC26A6) and enzymes (V-type H+ATPase, CAc, CA IV, ammoniagenic enzymes) involved in H+ secretion, bicarbonate reabsorption, and the net excretion of acidic and basic equivalents, ammonia, and inorganic phosphate are addressed. The role of sodium-phosphate cotransporter (Slc34a2b) and rhesus (Rh) glycoproteins (ammonia channels) in conjunction with apical V-type H+ ATPase and NHE3 exchangers in these processes are also explored. Nephrocalcinosis is an inflammation-like disorder due to the precipitation of calcareous material in the kidneys, and is listed as one of the most prevalent pathologies in land-based production of salmonids in recirculating aquaculture systems. The causative links underlying the pathogenesis and etiology of nephrocalcinosis in teleosts is speculative at best, but acid-base perturbation is probably a central pathophysiological cause. Relevant risk factors associated with nephrocalcinosis are hypercapnia and hyperoxia in the culture water. These raise internal CO2 levels in the fish, triggering complex branchial and renal acid-base compensations which may promote formation of kidney stones. However, increased salt loads through the rearing water and the feed may increase the prevalence of nephrocalcinosis. An increased understanding of the kidneys role in acid-base and ion regulation and how this relates to renal diseases such as nephrocalcinosis will have applied relevance for the biologist and aquaculturist alike.

Influence of umbilical cord pH on the outcome of hearing screening with otoacoustic emissions in healthy newborns

The effect of hypoxia on the functioning of the outer hair cells of the cochlea, which are responsible for the response to otoemissions used in neonatal hearing screening, is well known.The aim of this study is to determine the influence of mild to moderate variations in umbilical cord pH at birth on the outcome of hearing screening with otoemissions in healthy newborns without hearing risk factors.The sample is composed of 4536 healthy infants. The results show no significant differences in the hearing screening outcome between the asphyctic (<7.20) and normal pH group. Nor is a figure below 7.20 detected in the sample that is related to an alteration in the screening.When broken down into subgroups with known factors of variation in the screening result, such as gender or lactation, no significant differences in response were detected.Apgar ≤7 is significantly related to pH<7.20.In conclusion, mild-moderate asphyxia associated with delivery of healthy newborns, without auditory risk factors, does not alter the outcome of otoemission screening.

Quantitative Proteomic Analysis of Outer Membrane Vesicles from Fusobacterium nucleatum Cultivated in the Mimic Cancer Environment.

Fusobacterium nucleatum is a Gram-negative bacterium that has been identified as an important pathogenic gut bacterium associated with colorectal cancer. Compared with the normal intestine, the pH value of the tumor microenvironment is weakly acidic. The metabolic changes of F. nucleatum in the tumor microenvironment, especially the protein composition of its outer membrane vesicles, remain unclear. Here, we systematically analyzed the effect of environmental pH on the proteome of outer membrane vesicles (OMVs) from F. nucleatum by tandem mass tag (TMT) labeling-high-resolution liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. A total of 991 proteins were identified in acidic OMVs (aOMVs) and neutral OMVs (nOMVs), including known virulence proteins and putative virulence proteins. Finally, 306 upregulated proteins and 360 downregulated proteins were detected in aOMVs, and approximately 70% of the expression of OMV proteins was altered under acidic conditions. A total of 29 autotransporters were identified in F. nucleatum OMVs, and 13 autotransporters were upregulated in aOMVs. Interestingly, three upregulated autotransporters (D5REI9, D5RD69, and D5RBW2) show homology to the known virulence factor Fap2, suggesting that they may be involved in various pathogenic pathways such as the pathway for binding with colorectal cancer cells. Moreover, we found that more than 70% of MORN2 domain-containing proteins may have toxic effects on host cells. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses demonstrated that a number of proteins were significantly enriched in multiple pathways involving fatty acid synthesis and butyrate synthesis. Seven metabolic enzymes involved in fatty acid metabolism pathways were identified in the proteomic data, of which 5 were upregulated and 2 were downregulated in aOMVs, while 14 metabolic enzymes involved in the butyric acid metabolic pathway were downregulated in aOMVs. In conclusion, we found a key difference in virulence proteins and pathways in the outer membrane vesicles of F. nucleatum between the tumor microenvironment pH and normal intestinal pH, which provides new clues for the prevention and treatment of colorectal cancer. IMPORTANCE F. nucleatum is an opportunistic pathogenic bacterium that can be enriched in colorectal cancer tissues, affecting multiple stages of colorectal cancer development. OMVs have been demonstrated to play key roles in pathogenesis by delivering toxins and other virulence factors to host cells. By employing quantitative proteomic analysis, we found that the pH conditions could affect the protein expression of the outer membrane vesicles of F. nucleatum. Under acidic conditions, approximately 70% of the expression of proteins in OMVs was altered. Several virulence factors, such as type 5a secreted autotransporter (T5aSSs) and membrane occupation and recognition nexus (MORN) domain-containing proteins, were upregulated under acidic conditions. A large number of proteins showed significant enrichments in multiple pathways involving fatty acid synthesis and butyrate synthesis. Proteomics analysis of the outer membrane vesicles secreted by pathogenic bacteria in the acidic tumor microenvironment is of great significance for elucidating the pathogenicity mechanism and its application in vaccine and drug delivery vehicles.

NBCe1-B/C-knockout mice exhibit an impaired respiratory response and an enhanced renal response to metabolic acidosis.

The sodium-bicarbonate cotransporter (NBCe1) has three primary variants: NBCe1-A, -B and -C. NBCe1-A is expressed in renal proximal tubules in the cortical labyrinth, where it is essential for reclaiming filtered bicarbonate, such that NBCe1-A knockout mice are congenitally acidemic. NBCe1-B and -C variants are expressed in chemosensitive regions of the brainstem, while NBCe1-B is also expressed in renal proximal tubules located in the outer medulla. Although mice lacking NBCe1-B/C (KOb/c) exhibit a normal plasma pH at baseline, the distribution of NBCe1-B/C indicates that these variants could play a role in both the rapid respiratory and slower renal responses to metabolic acidosis (MAc). Therefore, in this study we used an integrative physiologic approach to investigate the response of KOb/c mice to MAc. By means of unanesthetized whole-body plethysmography and blood-gas analysis, we demonstrate that the respiratory response to MAc (increase in minute volume, decrease in pCO2) is impaired in KOb/c mice leading to a greater severity of acidemia after 1day of MAc. Despite this respiratory impairment, the recovery of plasma pH after 3-days of MAc remained intact in KOb/c mice. Using data gathered from mice housed in metabolic cages we demonstrate a greater elevation of renal ammonium excretion and greater downregulation of the ammonia recycling enzyme glutamine synthetase in KOb/c mice on day 2 of MAc, consistent with greater renal acid-excretion. We conclude that KOb/c mice are ultimately able to defend plasma pH during MAc, but that the integrated response is disturbed such that the burden of work shifts from the respiratory system to the kidneys, delaying the recovery of pH.

Screening of acid-tolerant hybrid Corn lines and parents using modified acid mineral soil

Screening of hybrid corn parent lines quickly and cheaply compared to hydroponic methods in the laboratory is needed to support the assembly of new high yielding varieties of acid tolerant corn. Addition of CaCO3 as equivalent to 2 t/ha (normal soil), while 0.5 t/ha AlCl3 (acidic). A total of 12 elite maize lines were tested based on relative root growth (RRG). Four sets of experiments were made, namely 2 sets normal soil media (pH 6.5) and 2 sets acid soil media (pH 4.3). Experimental design used in each experimental set was a randomized block with three replications. Results showed that rapid screening of hybrid maize parental lines could be carried out using modified soil acidity method by adding CaCO3 and AlCl3 to acid soil by measuring relative root growth (RRG) as the main variable. Corn obtained by genotypes No.80, MAL03x192, and Bisi-18 were classified as tolerant, MAL03x28, MAL03x182, MAL03x42, MAL03x44, MAL03x107, MAL03x115 were classified as moderately tolerant, while MAL03x100, MAL03x56, classified as sensitive. Screening of hybrid parent lines on acid soil modified to pH 4.3 (acidic) and normal pH 6.5 at seedling age 7 days after planting (dap) was more accurate than at seedling age of maize 14 dap.

Synergistic adsorption and degradation of sulfamethazine by tobacco stalk-derived activated biochar: Preparation, mechanism insight and application

Green preparation of high value-added products from biomass waste for environmental remediation has received significant attention. In this work, activated biochars were developed through two-step thermal process using tobacco stalk as the precursor. Textural properties of biochar can be effectively tuned by adjusting carbonization and activation parameters. An optimized biochar (700TS-1000–5), carbonized at 700 ℃ and then thermally activated at 1000 ℃ for 5 h, showed higher specific surface area (905.61 m2 g−1), rich porous structure, and abundant surface functional groups. 700TS-1000–5 showed excellent performance with a removal capacity of 99.37 mg g−1 for sulfamethazine (SMT) in 720 min, which was 4.3 times that of pristine biochar (700TS). And the SMT removal was high-efficient under normal environmental pH range. Adsorption and degradation simultaneously occurred during the whole process, which mainly relied on defects, functional groups, and·OH radicals. Moreover, this typical sample showed outstanding recycling ability and effectiveness of column experiment. Compared with KOH-assisted chemical activation, thermal activation had minor environmental impact and lower preparation cost through environmental and economic assessment. These findings not only propose a simple protocol for high-value reuse of agricultural waste but also shed new light on applications of tobacco stalk-derived biochar.

Quality assessment and evaluation of irrigation water and soil used for maize (Zea mays L.) production in Boloso Sore district, southern Ethiopia

Poor quality of irrigation water and soil are among the major factors determining maize productivity in Ethiopia. This study assessed and evaluated the quality of irrigation water and soil under maize production in Soke and Woybo irrigation schemes in Boloso Sore district, Ethiopia. Four water samples per site per season were collected from the first point of the irrigation schemes and farm gate for dry and rainy seasons in 2019/2020. Soil samples of 108 were collected from 36 points, from which 18 composited samples were taken for laboratory analysis. Results show that irrigation water of the two schemes is non-saline (electrical conductivity <0.2 dS m−1) and in the normal pH range (6.5–7.5). Maximum concentration of cations in irrigation water was in the order of sodium (22.3 mg l−1) > potassium (7.3 mg l−1) > calcium (6.2 mg l−1) > magnesium (3.1 mg l−1). Moderate to severe sodicity (sodium adsorption ratio of 10.9) was also recorded. Sulfate, nitrate, and phosphate contents in water were trace, and increased during rainy seasons in downstream. Textural classes of soils are clay loam to clay, and less compact to restrict root penetration (bulk density ≤1.4 g cm−3), have slow infiltration rate (≤0.13 cm h−1), and medium level of total available water (≤178 mm m−1). Soils are strongly acidic to neutral (pH: 5–6.5), salt-free, and have low soil organic carbon (≤2.1%), low total nitrogen (≤0.1%), low available phosphorus and sulfur, and low Ca2+: Mg2+ ratio. It can be concluded that the irrigation water in the study area has cation imbalance (poor quality) which affects soil quality and maize productivity. Likewise, soils of the study area have poor quality. Lime application, efficient fertilizer use, and organic matter applications can be suggested. Further study on optimizing fertilizer rates and irrigation levels has to be conducted to improve maize productivity.

Performances of plant leaf biosorbents for biosorption of phosphorous from synthetic water

Phosphorus acts as a vital part in the improvement of environment, manufacturing and agriculture. However, it can also become a contaminant in water bodies, posing a danger to the human, animals and the ecosystems. To address this issue, different methods exist for removing phosphorus from water, with bio-sorption being a mainly effective and eco-friendly option. Plant leaf biosorbents offer different levels of effectiveness, depending on the taxonomic group and pre-treatment of the plant, among other factors. In this research, locally available plant leaf biosorbents, including neem, javapalm, guava, sapota, custard apple, and mango leaves, were measured for their capability to eliminate phosphorus from water. Results indicated that mango leaves were the most effective, followed by javapalm, sapota, custard apple, neem, and guava leaves. The optimal conditions for phosphorus removal were a normal pH of 4–8, 1.2 g quantity, 60 min of contact time, a temperature of 25 °C, and a rotation speed of 100 rpm. Regeneration and reapplication of the plant leaf biosorbents can further improve the efficiency of the process.

Modulation of G-protein activation, calcium currents and opioid receptor phosphorylation by the pH-dependent antinociceptive agonist NFEPP.

N-(3-fluoro-1-phenethylpiperidine-4-yl)-N-phenyl propionamide is a newly-designed pain killer selectively activating G-protein-coupled mu-opioid receptors (MOR) in acidic injured tissues, and therefore devoid of central side effects which are typically elicited at normal pH values in healthy tissues. However, the neuronal mechanisms underlying NFEPP's antinociceptive effects were not examined in detail so far. Voltage-dependent Ca2+ channels (VDCCs) in nociceptive neurons play a major role in the generation and inhibition of pain. In this study, we focused on the effects of NFEPP on calcium currents in rat dorsal root ganglion (DRG) neurons. The inhibitory role of the G-protein subunits Gi/o and Gβγ on VDCCs was investigated using the blockers pertussis toxin and gallein, respectively. GTPγS binding, calcium signals and MOR phosphorylation were also investigated. All experiments were performed at acidic and normal pH values using NFEPP in comparison to the conventional opioid agonist fentanyl. At low pH, NFEPP produced more efficient G-protein activation in transfected HEK293 cells and significantly reduced VDCCs in depolarized DRG neurons. The latter effect was mediated by Gβγ subunits, and NFEPP-mediated MOR phosphorylation was pH-dependent. Fentanyl's responses were not affected by pH changes. Our data indicate that NFEPP-induced MOR signaling is more effective at low pH and that the inhibition of calcium channels in DRG neurons underlies NFEPP's antinociceptive actions.