Potassium Ratio Research Articles

J-shaped association between serum glucose potassium ratio and prognosis in heart failure with preserved ejection fraction with stronger predictive value in non-diabetic patients

Background: The relationship between serum glucose/potassium ratio (GPR) and the adverse outcomes in patients with heart failure with preserved ejection fraction (HFpEF) has not been completely clarified. Methods: Patients were included from the American cohort of the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial. The primary endpoint was the composite of cardiovascular mortality, aborted cardiac arrest, and hospitalization for HF. The Cox regression models were applied to calculate the hazard ratio (HR) and 95% confidence interval (CI) to examine the relationship between GPR and prognosis. Restricted cubic spline (RCS) curves were performed to explore the nonlinear relationship between GPR and the primary endpoint. Receiver Operating Characteristic (ROC) curves were constructed, and the areas under the curves (AUCs) for GPR and its components were compared using the DeLong test. Subgroup analysis and interaction effect were also explored. Results: A total of 1749 HFpEF patients were included. During the follow-up, 514 (29.4%) patients reached the primary outcome. An increase in GPR was independently associated with a higher risk in the primary endpoint [Tertile 3 vs. Tertile 1: HR (95% CI), 1.35 (1.07–1.70), P = 0.012] and HF hospitalization [Tertile 3 vs. Tertile 1: HR (95% CI), 1.57 (1.20–2.05), P = 0.001]. RCS curve showed a J-shape trend between GPR and primary endpoint (non-linear P = 0.002). The AUC for GPR was superior to that of the glucose and potassium (De long test P < 0.05). Additionally, the prognostic value of GPR was stronger in patients without diabetes and with less severe heart failure symptoms (P interaction < 0.05). Conclusion: A J-shaped relationship was existed between GPR levels and the primary outcome in HFpEF patients. An increased GPR was an independent predictor of poor prognosis in HFpEF patients, especially in non-diabetic patients and those with less severe heart failure symptoms.

Determining the alumina solubility in low-temperature KF-NaF-AlF3 melts using electrochemical methods

Alumina solubility in KF-NaF-AlF3 melt was estimated using square wave voltammetry and linear sweep voltammetry methods. A 45° inclined and horizontal electrode were used in square wave voltammetry and linear sweep voltammetry, respectively. The electrolyte used in this study had a cryolite ratio (CR) of 1.3 and a potassium ratio (KR) of 0.3 at 800 °C. Voltammograms were recorded on both electrodes at different alumina concentrations in the melt. Based on these studies, the alumina solubility in the studied melt is 3.879 wt%, which agrees with the literature.

Mitigating excessive heat in Arabica coffee using nanosilicon and seaweed extract to enhance element homeostasis and photosynthetic recovery

BackgroundGlobal warming-related temperature increases have a substantial effect on plant and human health. The Arabica coffee plant is susceptible to growing in many places across the world where temperatures are rising. This study examines how nanosilicon and seaweed extracts can improve Arabica coffee plant resilience during heat stress treatment (49.0 ± 0.3 °C) by maintaining mineral homeostasis and photosynthetic ability upon recovery.ResultsThe principal component analysis arrangement of four treatments, nanosilicon (Si), seaweed extract (SWE), Si + SWE, and control (CT), showed each element ratio of magnesium, phosphorus, chloride, potassium, manganese, iron, copper, and zinc per silicon in ambient temperature and heat stress that found influenced upper shoot rather than basal shoot and root within 74.4% of largest feasible variance as first principal component. Magnesium and iron were clustered within the silicon group, with magnesium dominating and leading to a significant increase (p ≤ 0.05) in magnesium-to-silicon ratio in the upper shoot under heat conditions, especially in Si and Si + SWE treated plants (1.11 and 1.29 fold over SWE treated plant, respectively). The SWE and Si + SWE treated plants preserved chlorophyll content (15.01% and 28.67% over Si-treated plant, respectively) under heat stress, while the Si and Si + SWE treated plants restored photosynthetic efficiency (Fv/Fm) better than the SWE treated plant.ConclusionsThe concomitant of the Si + SWE treatment synergistically protected photosynthetic pigments and Fv/Fm by adjusting the magnesium-silicon homeostasis perspective in Arabica coffee to protect real-world agricultural practices and coffee cultivation under climate change scenarios.

Abstract 4130314: High sodium, low potassium diet is associated with incident cardiovascular disease among US Hispanic/Latino adults: results from the Hispanic Community Health Study/Study of Latinos.

Background: Diets high in sodium and low in potassium are associated with increased blood pressure level but associations with cardiovascular disease (CVD) remain controversial. Few studies have evaluated this relationship among Hispanic/Latino adults. Objective: To assess whether dietary sodium and potassium are associated with incident CVD among diverse US Hispanics/Latino adults. Methods: The Hispanic Community Health Study/Study of Latinos (HCHS/SOL) is a cohort of 16,415 self-identifying Hispanic/Latino adults aged 18-74 four US urban communities in 2008-2011 (visit 1; V1). V1 included a comprehensive examination with in-person measurement of health information and interviewer administered questionnaires. Dietary sodium (mg/day) and potassium (mg/day) intakes were assessed from the average of two 24-hour dietary recall surveys administered by bilingual registered dietitians. CVD events occurring from V1 through 2019 were adjudicated by an expert panel of clinicians. We used Poisson regression to determine the association (incidence rate ratio, IRR) between sodium, potassium, and the sodium-to-potassium ratio, with CVD, using time to CVD as an offset. Models accounted for HCHS/SOL complex survey design and were adjusted for demographic, including Hispanic/Latino background, socioeconomic, and behavioral factors along with energy consumption, body mass index, cholesterol, and family history of CVD. Results: Among 15,291 participants without self-reported CVD at V1, mean age was 40 years, with 53% female. Mean daily intakes of sodium and potassium were 3,040 mg/day and 2,422 mg/day, respectively. Molar ratio of sodium to potassium was 1.33. Over 9.7 years of follow-up, there were 311 CVD events (2.0 events per 1,000 person years, 95% CI: 1.6, 2.5). In adjusted models, nutrients were associated with increased risk of CVD: by 17% for each 1g/day increment of sodium (IRR: 1.17, 95% CI: 1.03, 1.33); by 29% for each 1g/day decrement of potassium (IRR: 1.29, 95% CI: 1.01, 1.64); and by 112% for each 0.5 molar increment of sodium to potassium ratio (IRR: 2.12, 95% CI: 1.13, 4.11). Conclusions: In a large diverse sample of Hispanic/Latino adults, high dietary sodium and low dietary potassium were independently associated with an increased risk of CVD. Results underscore the importance of intensifying public health interventions to improve nutrient quality, by reducing dietary sodium and increasing dietary potassium consumption as a means of preventing CVD.

Association between urinary sodium-to-potassium ratio, elevated blood pressure phenotypes and microalbuminuria: Tehran Lipid and Glucose Study

This cross-sectional study investigated the associations between urinary sodium (UNa) to potassium (UK) ratio, different phenotypes of elevated blood pressure (BP), and microalbuminuria (MAU) in a cohort of the Tehran Lipid and Glucose Study (TLGS). Adult participants (n = 1782, mean age of 43.0 ± 13.7 years and 46.0% were men) were recruited (2015–2017) for measurements of spot urinary metabolites, i.e., Na, K, creatinine (Cr), microalbumin, and BP. Multinomial logistic regression was used to estimate the relative risk ratios (RRR) of elevated BP phenotypes [i.e., isolated systolic (ISH), diastolic (IDH), and systolic-diastolic (SDH) hypertension], and binary logistic regression was used to estimate odds ratios (ORs) of MAU across quintile categories and per each SD-increment of UNa-K ratio. Mean UNa, UK, and its ratio was 137 ± 57.4, 72.1 ± 36.6 mmol/L, and 2.31 ± 1.41, respectively. Subjects with UNa-K > 3.14 had higher prevalence of ISH (3.4 vs. 1.1%), SDH (11.0 vs. 6.2%), and MAU (14.1 vs. 6.2%) (P for all < 0.05). Highest compared to the lowest UNa-K ratio values (> 3.14 vs. <1.23) was associated with an increased probability of SDH (RRR = 1.79, 95% CI 1.09–3.19) and MAU (OR = 2.53, 95% CI 1.23–5.20). Every 1 SD-increment of the UNa-K ratio was associated with a 29 and 38% increased chance of having SDH and MAU, respectively. Our findings imply that a high UNa-K ratio may be a potential risk factor for elevated BP and renal dysfunction.

Association between serum glucose potassium ratio and mortality in critically ill patients with intracerebral hemorrhage

The effect of serum glucose-to-potassium ratio (GPR) on cerebrovascular diseases has been previously validated. However, the value of the GPR in patients with severe intracerebral hemorrhage (ICH) requiring ICU admission remains unclear. This study aimed to investigate the association between the GPR and the clinical prognosis of critically ill patients with ICH. This study identified patients with severe ICH requiring ICU admission from the Medical Information Mart for Intensive Care (MIMIC-IV) database and divided them into quartiles based on GPR levels. Outcomes included 30-day, 90-day, and 1-year mortality rates. The association between the GPR and clinical outcomes in critically ill patients with ICH was elucidated using Cox proportional hazards regression analysis and restricted cubic splines. In total, 2018 patients (53.8% male), with a median age of 70 years, were enrolled in the study. The 30-day, 90-day, and 1-year mortality rates were 23.9%, 30.1%, and 38.4%, respectively. Per multivariate Cox proportional hazards analysis, an elevated GPR was significantly associated with all-cause mortality. After adjusting for age, sex, Charlson Comorbidity Index, white blood cell count, red blood cell count, platelet count, and Glasgow Coma Scale, patients with an elevated GPR had a higher 30-day mortality (hazard ratio [HR]: 1.32; 95% confidence interval [CI]: 1.22–1.42; P < 0.001), 90-day mortality (HR: 1.27; 95% CI: 1.18–1.37; P < 0.001) and 1-year mortality (HR: 1.22; 95% CI: 1.14–1.31; P < 0.001) when analyzed as a continuous variable. Furthermore, analysis using restricted cubic splines demonstrated a consistent and progressive escalation in the risk of all-cause mortality with an elevated GPR. The GPR was significantly associated with short- and long-term all-cause mortality in critically ill patients with ICH. This finding demonstrates that GPR may be useful in identifying patients with ICH at a high risk of all-cause mortality.

Serum electrolyte abnormalities in cats with chronic inflammatory enteropathy.

Limited information is available on electrolyte abnormalities in cats with chronic inflammatory enteropathy (CIE). Report the prevalence of electrolyte abnormalities in cats with CIE compared to other gastrointestinal disorders, and determine their association with disease and outcome variables in cats with CIE. Three hundred twenty-eight client-owned cats from 2 referral hospitals: CIE (132), alimentary small cell lymphoma (29), acute gastroenteritis (48), and healthy controls (119). Retrospective study comparing serum electrolyte concentrations at time of diagnosis among the 4 groups of cats, and associations with clinical signs, intestinal mucosal fibrosis scores, treatment subclassification and outcome in CIE. Cats with CIE had lower sodium and higher potassium concentrations and lower sodium: potassium ratios compared with healthy cats (P < .001, P = .01, and P < .001, respectively). Cats with CIE and a duodenal mucosal fibrosis score of 2 had lower sodium and lower total calcium concentrations compared with cats that had a score of 0 (P = .02 and P = .01). Cats with CIE and a colonic mucosal fibrosis score of 1 had higher potassium concentrations and lower sodium: potassium ratios compared with cats that had a score of 0 (P = .03 and P = .01). Cats with CIE that died as a result of their disease had higher potassium concentrations and lower sodium: potassium ratios compared to cats that were alive (P = .02 and P = .01). Electrolyte abnormalities occur with CIE and, in particular, in cats with higher fibrosis scores and worse outcomes. Further research should aim to determine the pathogenesis of these findings and identify novel therapeutic targets for cats with CIE.

Spot Urine Sodium to Potassium Ratio as a Tool to Assess Severity and Mortality among Patients with Decompensated Cirrhosis having Ascites

Background: Decompensated cirrhosis of liver is considered as a systemic disease affecting the functions of several other organs. Renal function is an independent prognostic factor for patients with decompensated cirrhosis, but assessing renal function through glomerular filtration rate are not convenient, especially for routine use. Previous study found that spot urinary sodium to potassium ratio (UNa/K) was associated with renal dysfunction which influences the severity and outcome in decompensated cirrhosis of liver patients having ascites. Aims and objectives: The present study was aimed to determine the relation of the ratio of sodium to potassium in randomly collected urine samples with severity of disease and mortality in decompensated cirrhosis having ascites. Materials and Methods: This longitudinal study was conducted at the Department of Gastrointestinal, Hepatobiliary and Pancreatic Disorders, BIRDEM General Hospital, Shahbagh, Dhaka, Bangladesh, from July, 2019 to August, 202l. A total of 150 patients with a confirmed diagnosis of decompensated cirrhosis with ascites were enrolled in this study. A detailed history and thorough clinical examination were carried out in each patient, along with relevant investigations. Data collection was done through a structured questionnaire. Data were analyzed using the statistical software SPSS 23. Results: Age of the patients was 59.0±12.91 (mean±SD) years, male predominance was observed (52%). The UNa/K ratio was 4.24±3.25 (mean±SD) with a range of 0.42 to 18.46. Diagnostic accuracy of UNa/K ratio in the detection of severity and mortality was estimated by the receiver operating characteristic (ROC) curve. The AUC of UNa/K ratio was 0.608 and 0.640 for severity and mortality respectively. Sensitivity, specificity, PPV and NPV at cut-off 2.55 were 50.0, 66.0, 42.4 and 72.5; at 2.65 were 54.0, 66.0, 44.3, and 74.2; at 2.87 were 58.0, 62.0, 43.3, and 74.7; at 3.21 were 58.0, 58.0, 40.8, and 73.4 respectively for severity score (MELD). Patients with UNa+/K+ less than 2.87 or equal, had a significantly higher MELD score category (p= 0.02). At 3 months follow-up, 24.7% mortality was observed. Sensitivity, specificity, PPV and NPV at cut-off 1.62 were 51.4, 85.8, 54.3 and 84.3; at 1.79 were 54.1, 79.7, 46.5 and 84.1; at 1.83 were 59.5, 77.0, 45.8 and 85.3; at 2.87 were 58.0, 62.0, 43.3, and 74.7 respectively for mortality. The UNa/K ratio was statistically low among the patients who didn’t survive (p&lt;.05). Conclusion: This study revealed that decreased ratio of spot urinary sodium to potassium was associated with the severity and mortality among decompensated cirrhosis of liver patients with ascites. Bangladesh Crit Care J September 2024; 12 (2): 118-124

Nutrition for commercial flower production of Longiflorum asiatica (LA) hybrid under northern plains

The study was conducted during the winter seasons, comprising the various combinations of inorganic fertilizers (N, P2O5, and K2O) and organic manure (FYM). Treatment T24 [(25 t FYM+160 kg N+120 kg P2O5+100 kg K2O)/ha] emerged as the statistically significant treatment, outperforming others in respect of tallest plant (122.43 cm), leaf count per plant (79.33), leaf length (7.90 cm), and early flower bud initiation (28.01 days), bud initiation to colour shown (47.11 days), and colour shown to flower opening (6.10 days). This treatment also tended to show the longest flower retention on plant (15.30 days), number of flower buds per plant (4.20), bud length (8.96 cm), stalk length (110.10 cm), stalk diameter (0.96 cm), flower diameter (22.98 cm), total chlorophyll content (6.50 mg/g), leaf nitrogen (4.70%), potassium (4.10%), and net assimilation ratio (NAR) (0.0065 mg/cm2/ day). Treatment T23 [(25 t FYM+120 kg N+90 kg P2O5+75 kg K2O)/ha] proved next best treatment. The lowest value was recorded in T25 (Control). Overall, treatment T24 proved to be the most effective treatment statistically for the commercial flower production of LA hybrid lilium for northern Indian plains.

Abstract P425: Role of 24h UNaK ratio in patients with hypertension and resistant hypertension by gender and race

RHTN is defined as blood pressure above goal despite using ≥3 antihypertensive medications. Patients with RHTN are at an increased risk for CVD compared to those with more easily controlled hypertension (HTN). High sodium intake and higher 24h urinary (U) sodium (Na) potassium(K) ratio is associated with higher CVD risk. The role of this ratio in RHTN has not been investigated. Methods: We conducted a cross-sectional analysis of a large cohort of 2397 black and white patients with RHTN who were referred to the RHTN Clinic at the University of Alabama at Birmingham and who underwent a 24h urine collection. Patients with HTN served as a control group. Results: Patients with RHTN had significantly higher 24h UNaK ratio than patients with HTN (3.2±1.6 vs 3.6 ±2.0, p &lt;0.001 ) and had an earlier onset of HTN (38.8±13.7 years (yrs) vs 47.6±16.2 yrs, p=0.001) and longer duration 17.6±11.2 vs 12.0±10.7 yrs, p=0.001), higher BMI (32.6±7.2 vs 29.98±6.5 kg/m2), and 24-hourUNa (181±88 vs 164±77 mmol, p=0.01). Within the RHTN group (n=1340) females had a significant higher 24h UNaK ratio than males (3.5±1.9 vs 3.2±1.7, p =0.006) and blacks had a significant higher 24h UNaK ratio than whites (3.0±1.6 vs 3.9±2.0, p&lt;0.001). Conclusion: Higher 24h UNaK ratio as index of higher sodium and lower potassium intakes were found in patients with RHTN as well as resistant hypertensive females and blacks and may explain certain higher CV risks in these populations.

Usefulness of plasma glucose to potassium ratio in predicting the short-term mortality of patients with aneurysmal subarachnoid hemorrhage

Rationale and objectivesTo investigate the relationship between the glucose/potassium ratio (GPR) at admission and 30-day mortality in patients diagnosed with aneurysmal subarachnoid hemorrhage (SAH) in the emergency department (ED). Materials and methodsPatients with a modified Rankin Scale (mRS) score of ≤2 before SAH and patients aged 18 years or older were included in the study. The patients were divided into two groups based on their functional outcomes (poor-good) and 30-day mortality rates (survivor and non-survivor) and their clinical and laboratory values were compared. ResultsThe study included 134 patients with a mean age of 65.9 ± 16.7 years, of whom 68 (50.7 %) were female. The mean glucose and GPR levels in the poor functional outcome group were significantly higher than those in the good functional outcome group (p = 0.003, p = 0.03, respectively). The mean glucose and GPR levels in the non-survivor group were significantly higher than those in the survivor group (p = 0.004, p = 0.023, respectively). Multivariate logistic regression analysis identified GPR as an independent predictor of 30-day mortality (p = 0.043, OR: 4.041, 95 % CI: 1.45–26.147), alongside the Rankin Scale score (p = 0.002, OR: 12.714, 95 % CI: 2.578–62.706). Other variables, including age, Hunt-Hess score, and Glasgow Coma Scale, were not statistically significant. ConclusionThe findings indicate that the GPR is a significant independent predictor of short-term mortality in patients with aneurysmal subarachnoid hemorrhage. The translation of these findings into clinical practice may help achieve better outcomes in the management of SAH patients.

O81 EFFECT OF ANTIHYPERTENSIVE MEDICATIONS ON URINARY SODIUM TO POTASSIUM (Na/K) RATIO

Background: The urinary sodium to potassium ratio (Na/K) greater than 2 indicating either excess sodium or insufficient potassium intake. However, the effect of antihypertensive medications on the urinary Na/K ratio has not been evaluated. We hypothesized that antihypertensive medication would acutely affect the urinary Na/K ratio. Methods: Male and female C57BL/6J mice, 14 weeks old, and a separate cohort of 24-month-old mice were subjected to a regular chow diet (NaCl 0.4%) and a high salt diet (4%). Urinary Na/K ratios in spot urine samples were measured three times a week. After baseline measurements, all animals were treated with one antihypertensive medication for 2 weeks, followed by a one-week washout period. The effects of enalapril (25 mg/kg/day), hydrochlorothiazide (25 mg/kg/day), and amlodipine (10 mg/kg/day)—were compared under a high salt diet mimicking human salt consumption. Urinary Na/K ratios collected on day 1 (acute) and day 8 (subacute) after initiating medication were compared to the vehicle period using a two-way ANOVA. Medication was administered with food using gel food pellets. Results: Under regular chow, the urinary Na/K ratio was 0.65±0.58 (n=15) with no interaction between sex or age (all p&gt;0.05). Under a high salt diet, the urinary Na/K ratio increased to 4.5±2.2 (p&lt;0.01 vs. regular chow) with no differences between sex and age. After the washout period, enalapril, both acutely and subacutely, did not affect the Na/K ratio. Similarly, hydrochlorothiazide did not affect the Na/K ratio in either period. However, amlodipine reduced the Na/K ratio in both acute and subacute periods (p&lt;0.001). No interaction was observed with sex or age. The effect of amlodipine was related to higher potassium excretion (43.9±23 vs. 81.6±33 meq/L; p&lt;0.001) with no changes in sodium excretion (152.2±75 vs. 173.3±43.5 meq/L; p=0.8). Conclusion: The Na/K ratio reflects salt and potassium consumption. The Na/K ratio is not affected by enalapril or hydrochlorothiazide. Amlodipine decreases the Na/K ratio acutely and subacutely due to increased potassium excretion.

Evaluating the prognostic value of the stress index in trauma patients

BackgroundThe stress index (SI), defined as the serum glucose to potassium ratio, has emerged as a potential prognostic indicator in some patient populations. This study aims to evaluate the predictive value of SI on the trauma patients sustained by all trauma causes. MethodsA retrospective analysis was conducted on 20,040 adult trauma patients admitted to a single trauma center from January 1, 2009, to December 31, 2022. The SI was calculated according to the serum levels of glucose (mg/dL) and potassium (mEq/L) upon patients’ arrival to emergency room. The enrolled patients were stratified into two groups based on an optimal SI cutoff value determined by receiver operating characteristic (ROC) curve analysis. The association between SI and in-hospital mortality, as well as other clinical outcomes, was assessed using multivariate logistic regression, adjusting for potential confounders. ResultsThe mortality patients had a significantly higher SI (59.7 ± 30.6 vs. 39.5 ± 17.5, p < 0.001) than those who survived. The SI was identified as a significant independent predictor of mortality (odds ratio [OR] 4.65, 95 % confidence interval [CI]: 2.61–8.27, p < 0.001) in the multivariate analysis. In addition, patients in the high SI group (≥42.7) demonstrated significantly worse outcomes, including higher in-hospital mortality (7.5 % vs. 1.4 %, p < 0.001), longer hospital stays compared to the low SI group (<42.7). ConclusionThe SI serves as a simple and valuable prognostic tool in risk stratification of the trauma patients.

System Inflammation Response Index and Serum Glucose-Potassium Ratio as Prognostic Indicators for Hemorrhagic Moyamoya Disease

Hemorrhagic moyamoya disease (HMMD) can result in poor outcomes. Serum biomarkers may play a significant role in predicting HMMD outcomes. This study retrospectively analyzed the correlation between serum biomarkers at the time of admission and outcomes for patients with HMMD. We evaluated 270 patients with HMMD admitted to Yijishan Hopital of Wannan Medical College between July 2017 and April 2023. The patients were categorized into 2 groups according to their modified Rankin Scale scores at 3months after discharge. Univariate and multivariate analyses were used to identify the associations between biomarkers and clinical outcomes. Receiver operating characteristic curves were obtained to investigate the potential of the biomarkers for predicting prognosis. Of the 270 patients analyzed, 96 (35.6%) had unfavorable outcomes. The potential predictors were identified using the univariate analysis. The subsequent multivariate logistic regression analysis showed that the systemic inflammatory response index (SIRI) (odds ratio 0.86, 95% confidence interval 0.75-0.98, P=0.028] and serum glucose to potassium ratio (GPR) (odds ratio 0.53, 95% confidence interval 0.38-0.76, P<0.001) were independent risk factors of poor outcomes. The receiver operating characteristic analysis indicated that patients with a higher SIRI (≥2.12) and GPR (≥1.75) levels were more likely to have unfavorable outcomes. An elevated GPR and SIRI at admission were associated with a poor clinical outcome at the 3-month follow-up for patients with HMMD. Therefore, these biomarkers could be considered in future management decisions for these patients.

Effects of restoration years on soil stoichiometric ratios in subtropical secondary forests.

Soil stoichiometric ratios serve as valuable indicators for the composition and quality of soil organic matter. While available studies predominantly examine the soil stoichiometric ratios of carbon (C), nitrogen (N), and phosphorus (P), limited attention has been paid on the influence of forest restoration on soil stoichiometric ratios of potassium (K), calcium (Ca), and magnesium (Mg). We analyzed soil K, Ca, and Mg content, as well as elemental stoichiometric ratios, in secondary forests with varying restoration periods (5, 8, 21, 27 and 40 years) and a natural forest, in order to examine the impact of forest restoration on soil stoichiometry. The results showed that soil C and N contents decreased significantly with increasing soil layers. Soil stoichiometric ratios decreased significantly with increasing soil layers except for K:P, Mg:P, and P:Ca. With the increases of forest restoration years, soil C and N contents significantly increased in 0-10 cm soil layer, Ca content in 10-20 cm soil layer significantly increased, and total P content in 20-40 cm layer significantly decreased. However, soil K and Mg contents in each soil layer did not differ among five restoration ages. With the increases of restoration years, C:Ca, N:Ca and P:Ca in 0-10 cm soil layer significantly increased, and C:P, N:P, and K:P in 20-40 cm soil layer significantly increased, while P:Ca in 20-40 cm soil layer significantly decreased. In all soil layers, K:P and Mg:P were significantly and negatively correlated with soil total P content, and C:Ca and N:Ca were significantly and positively correlated with soil mineral N, available P, and available K content. With the increases of the restoration ages of secondary forests, soils are gradually P-limited and progressively restricted by Ca element in the later years, leading to the limitation of multiple nutrients.

PHYSICO-CHEMICAL COMPOSITION OF PALM KERNEL SHELL ASH (PKSA) AS A POTENTIAL MINERAL SUPPLEMENT IN LIVESTOCK NUTRITION

The aims of this study were to determine the physico-chemical composition of palm kernel shell ash (PKSA) as a potential mineral supplement in livestock nutrition. Properties such as bulk density, water holding capacity, specific gravity, ash yield percentage and pH of the PKSA were evaluated. The mineral content was also assayed to ascertain its concentrations of minerals. Results obtained showed that PKSA had 92.68% dry matter, 0.8206 g/cm3 bulk density, 0.8977 g water/g feed water holding capacity, 0.8149 specific gravity and was mildly alkaline (8.39). The order of mineral elements in PKSA were K&gt;Mg&gt; Ca&gt; P&gt; Na Fe&gt; Mn&gt; Zn&gt; Cu. A calcium/phosphorus ratio of 1.01 and sodium/ potassium ratio of 0.15 was also calculated for PKSA. Thus, PKSA can serve as a mineral supplement in livestock feeding.

Macronutrients dynamics in copper-contaminated soils: Implications for hemp growth and its phytoremediation potential

Fibrous plants with higher biomass, particularly industrial hemp, have ability to withstand and accumulate significant quantities of heavy metals from contaminated environments. The present study aimed to evaluate the dynamics of different levels (ratios) of macronutrients nitrogen, phosphorus and potassium (NPK) viz., NPK1NPK (1:1:1); NPK2NPK (2:1:1); NPK3NPK (3:1:2); NPK4NPK (4:1:2) on hemp growth and Cu contents under various levels of Cu stress (100, 400 and 800 mg kg−1 on dry soil basis using CuSO4·5H2O). Results revealed that by increasing the Cu stress, growth and biomass decreased linearly and lipid per oxidation and enzymatic antioxidants increased. Balanced application of NPK improved the biomass and decreased the membrane damage by the modulation of malonaldehyde contents. Maximum concentration of Cu in roots (377.47 ± 4.90 mg kg−1), shoots (137.45 ± 5.60 mg kg−1) and (150.07 ± 3.57 mg kg−1) was recorded at Cu3NPK2 treatment as compared to control. Maximum translocation factor (TF) and bioaccumulation coefficients (BAC) in the shoots and leaves of hemp plant were noticed where Cu stress was applied at the rate of 100 mg kg−1. However, BAC and TF were below 1. The NPK2 treatment enhanced biomass and increase Cu content both in leaves and stems, rather than the roots. Our study suggests that balanced application of NPK is a practicable approach to alleviate Cu stress and improve biomass production of industrial hemp plant. These findings indicate that optimum nutrient supply, under Cu stress, can maximize the growth potential and overall health of industrial hemp, making it a viable option for phytoremediation and sustainable agriculture on contaminated soils.

Artificial neural networks in soil quality prediction: Significance for sustainable tea cultivation

In today's era artificial intelligence is quite popular, one of the most effective algorithms used is Artificial Neural Networks (ANN). In this study, the determination of soil quality using the Soil Management Assessment Framework (SMAF) model in areas where tea cultivation is carried out at the micro-watershed scale and the predictability of soil quality using ANN were evaluated. According to the results, the soil quality indices of tea-growing areas were generally classified as “medium” between 55 and 70 %. Among the evaluated features for determining soil quality, the highest relative importance value was for soil organic carbon content (13 %) and potential mineralizable nitrogen (13 %), whereas the lowest values were for exchangeable potassium (4 %) and sodium adsorption ratio (SAR) (4 %). In addition, when comparing the actual and predicted values for soil quality prediction using ANN, the Lin's concordance correlation coefficient (LCCC), ratio of performance to deviation (RPD), and R2 values were found to be 0.93, 2.95, and 0.89, respectively. Significant properties for the determined values within a 90 % predicted interval were found to be organic matter, microbial biomass carbon, bulk density, and aggregate stability of the soils. Moreover, the uncertainty values (standard deviation) in the model predictions were determined to be within the range of 1.01–4.56 %. Consequently, the Soil Quality Index (SQI) obtained from the SMAF model using 12 soil properties in tea-growing areas could be accurately predicted using ANN. As a result of this study, digital maps showing the spatial distribution of SQI and the predicted uncertainties can help monitor SQI levels in this area.

Elemental geochemistry insights into source inputs, paleo-productivity, and paleo-depositional conditions of the Montney Formation

The analysis of the elemental composition of sediments provides valuable information about input sources, paleoredox conditions, or paleoproductivity. In this study, 1498 rock samples from six wells within the Triassic Montney Formation in Central Alberta, Western Canada, were analyzed using energy-dispersive X-ray fluorescence (ED-XRF). Wavelength dispersive X-ray fluorescence measurements were used to build and validate a Montney-specific calibration to interpret elemental concentrations from the ED-XRF dataset. The calibration accounted for heterogeneities, matrix variations and unique elemental associations that may be present within the Montney Formation. Sediment input sources are interpreted based on cross-plots of proxy elements to be terrigenous, carbonates and biogenic in origins. Analysis of multiple paleoredox proxies indicated the environment of deposition to be mainly oxic. The ratios of potassium (K) to rubidium (Rb) were used as a paleoclimate proxy. Results suggest the predominance of low chemical weathering attributed to a hot and arid paleoclimate during deposition of Montney Formation sediments. Phosphorous concentrations were determined to be strongly associated with Ca, as such it was interpreted to be inorganically sourced, thereby precluding it from being used to assess paleoproductivity. Excess Si interpreted to be biogenically sourced was used in interpreting moderate and high paleoproductivity for the Montney formation. This work demonstrates the versality of matrix-specific calibrated ED-XRF measurements as a valuable, cost efficient, standalone technique in geochemical analysis for characterizing geological formations.

Optimization of Sodium-Potassium Ratio in Cow Diets

In the conditions of the Nakhchivan Autonomous Republic, research has been carried out on the prevention of metabolic disorders and optimization of the sodium-potassium ratio in the feed ration of cows. The diets were identical in composition and nutritional value, but the ratio of sodium and potassium in the groups was different due to different amounts of table salt. During the stall period of the experiment, the ratio of sodium and potassium in group I was 0.36, in group II — 0.43, and in group III — 0.48. It should be noted that this attitude in groups II and III contributed to a greater consumption of roughage and succulent feed than in the control group. During the grazing period, cows of all groups also received the same rations. However, the ratio of sodium and potassium in them was different. Thus, in group II it was 0.32, in group III — 0.41 versus 0.24 in the control. In group I for 1 feed units sodium accounted for 5.7 g, in II — 7.6 and III — 10.0 g. Cows of groups II and III consumed more grass on pasture by 4.8 and 9.6%, and green fertilizer by 3.2 and 7.6% compared to control. The amount of grass eaten on pasture was determined using the reverse calculation method. On average, per lactation in groups II and III there was 1.4 and 3.0 g more sodium per feed unit, respectively, than in group I. The nutritional value of the diets corresponded to the needs and level of productivity of the animals. Thus, optimizing the sodium-potassium ratio in the diets of highly productive cows by increasing the rate of sodium chloride by 40% in the stall and by 100% in the grazing periods with excess potassium in the diets ensures improved mineral metabolism, increases the use of nutrients and increases milk yield by 4%. Fat content by 8,8% on average per lactation.