Weak Linear Correlation Research Articles

From SPECT/CT towards absolute quantification? - the case of unilateral condylar hyperplasia of the mandible

BackgroundUnilateral condylar hyperplasia (UCH) of the mandible is a rare condition characterized by asymmetric growth of the mandibular condyles. Bone scintigraphy with SPECT(/CT) is commonly used to diagnose UCH and guide treatment. Still, varying results have been reported using the traditional threshold of 55%:45% in relative tracer uptake. While absolute quantification of uptake on SPECT/CT could improve results, optimal correction and reconstruction settings are currently unknown.MethodsThree anthropomorphic phantoms representing UCH were developed from patient CT volumes and produced using 3D printing technology. Fillable spherical inserts of different sizes (Ø: 8–15 mm) were placed in the condylar positions representing symmetrical and asymmetrical distributions. Recovery coefficients were determined for SPECT/CT using various reconstruction corrections, including attenuation and scatter correction (ACSC), resolution modeling (RM), and partial volume correction (PVC) using phantom measurements. Uptake ratios between condyles and condyle to clivus were evaluated. Finally, the impact of these correction techniques on absolute activity and diagnostic accuracy was assessed in a retrospective patient cohort for the diagnostic threshold of 55%:45%.ResultsThe activity was only partially recovered in all spherical inserts (range: 22.5–64.9%). However, RM improved relative recovery by 20.2–62.3% compared to ACSC. In the symmetric phantoms, the 95% confidence interval (CI) of condyle ratios included the diagnostic threshold (57.6%:42.4%) for UCH when using ACSC potentially leading to false positives, but not for ACSCRM datasets. Partial volume corrections coefficients from the NEMA IQ phantom was positionally dependent, with improvements seen performing PVC using coefficients derived from anthropomorphic phantoms. Retrospective application in a patient cohort showed only a weak linear correlation (R²: 0.25–0.67) and large limits of agreement (9.6–12.5%) between different reconstructions. Up to 44% of patients were reclassified using the 55%:45% threshold. Using clinical outcome data, ACSCRM had highest sensitivity (91%; 95% CI 59–100%) and specificity (66%; 95% CI 47–81%), significantly improving specificity (P = 0.038).ConclusionsAnthropomorphic phantoms were shown to be essential in determining optimal settings for acquisition, reconstruction, and analysis. SPECT/CT reconstructions with attenuation and scatter correction and resolution modeling are recommended and could improve specificity when using the 55%:45% threshold to assess condylar growth.

Achieving SOC Conservation without Land-Use Changes between Agriculture and Forests

Global land-use changes impact soil’s ability to perform essential functions. This study investigates whether soil organic carbon (SOC) can be conserved without altering land use in traditional farming systems and degraded natural forests, focusing on ‘disturbed’ agricultural soils and ‘undisturbed’ forest soils. We also examine the influence of dominant crops on SOC within the top 30 cm of soil in data-deficient regions of Nepal. Using a multi-stage cluster sampling design, we tested 12 regression models to identify the best relationships among variables such as SOC, soil bulk density (BD), pH, dominant crops, climate, topography, and management practices. Our analysis revealed similar SOC levels in both disturbed and undisturbed soils, indicating significant degradation in forested areas, whereas traditional farming systems could support SOC and preserve farm-based indigenous knowledge alongside food security. Further, SOC stocks varied significantly (p < 0.05) across different cropping systems, suggesting that managing dominant crops could be a strategy to optimize SOC, with these crops serving as indicators. Additionally, our results show that the weak linear correlation between SOC and BD in regularly disturbed soils, such as farmlands, where anthropogenic activities frequently alter soil bulk density, may be misleading when estimating bulk density-dependent SOC. This finding suggests the need for further research into varying degrees of anthropogenic disturbance in soil to confirm these results. While the site-specific nature of the findings warrants caution with respect to generalization, they provide valuable insights for carbon monitoring, climate actions, ecosystem health, and land-use management in similar traditional farming systems and degraded forests, particularly in data-poor regions.

RESOURCE STEWARDSHIP AND CLIMATE SMART AGRICULTURE IN LAIKIPIA COUNTY, KENYA

Objective: To examine the extent to which resource stewardship influences the performance of climate-smart agriculture projects in Laikipia County, Kenya. Theoretical Framework: The study was anchored on the Stewardship theory that envisages that unsupervised managers, will derive their satisfaction from the organization's success hence, remain accountable stewards. Judicious stewardship is the only way to achieve food security in a healthy ecology. Method: A concurrent mixed method approach that adopted the descriptive cross-sectional survey and correlational design was employed to study two World Bank-sponsored Kenya Climate Smart Agriculture projects. Stratified and Simple random sampling were employed to get a sample of 225 small-scale farmers and purposeful sampling identified four key informants. Data was collected using questionnaires and interview guide and analyzed using descriptive, inferential, and content data analysis techniques. Results and Discussion: The respondents’ opinions on resource stewardship had a composite mean and standard deviation of 3.47 and 1.138 respectively. The relationship between resource stewardship and the performance of climate-smart projects had a weak linear correlation of (r= -0.007) and p-value (p=0.923>0.05) indicating a weak and insignificant relationship. Despite the portrayed confidence in resource stewardship, stewardship is not a quick-fix approach hence, detested in the use of resources. Research Implications: Consequently, it is vital to have policies that enforce, promote, and subsidize activities that stimulates stewardship in food production. Originality/Value: This study contributes to the literature by providing reliable and triangulated empirical data through authentic methodology enhancing suitability for data generalisability and replicability. The relevance and value of this research are evidenced by the need to promote food security in pursuance of the achievement of sustainable development goals.

Correlation of Left Atrial Volume Index with Pro-BNP in Heart Failure with Preserved Ejection Fraction

Objective: To determine the correlation between left atrial (LA) volume index and Pro- BNP in heart failure patients with preserved ejection fraction. Methodology: This descriptive Cross-Sectional Study was conducted at Department of Cardiology, Liaquat University of Medical & Health Sciences (LUMHS), Jamshoro, Pakistan, during Six months after the approval of synopsis from March 26, 2021 to September 25, 2021. All patients who fulfilled the inclusion criteria and visited to LUMHS, Jamshoro were included in the study. Informed consent was taken after explaining the procedure, risks and benefits of the study. Peripheral venous blood samples were obtained for assessment of pro- BNP level. A detailed comprehensive echocardiography was performed in all patients. All the collected data were entered into the proforma attached at the end and used electronically for research purpose. Results: The age of the patients ranged from 19 to 59 years with a median of 58 with interquartile range 12. In distribution of gender, 20 (60.5%) patients were male while 13 (39.4%) were female. Pearson’s correlation coefficient showed weak and non-significantly linear correlation between left atrial volume index and Pro-BNP levels i.e. (r= 0.134) in the region P < 0.05. Conclusion: It is to be concluded that there was a weak correlation between left atrial volume index and Pro-BNP levels. More studies are necessary to evaluate the statistical association with a larger sample size and with more parameters in multiple study centers in Pakistan are needed to validate the findings of the present study.

ESTIMATION OF STATURE FROM NASAL HEIGHT IN MALE AND FEMALE STUDENTS IN UDAIPUR

Objective: Stature refers to a person's height when standing upright. It is a vital measure of physical identity. In archaeological operations or forensic exams following a mass disaster, height is estimated using rudiments or bone pieces for identification. In order to determine stature, separate regression formulae should be developed for each population group. Methods: This cross-sectional study was conducted at Department of Anatomy, Pacific Institute of Medical Sciences, Umarda, and Udaipur. A total of 110 students (55 males and 55 females) aged between 18 to 25 y, participated in this study. Those with craniofacial defects were excluded from study. Height was measured from vertex to floor by stadiometer. Results: The study showed that in males mean values are significantly higher than females for both nasal height as well as stature; nasal height in (male 48.54±3.584 mm; female 46.75±3.763 mm) and stature in (male 170.3±7.902 cm; female 159.61±5.383 cm). In total student’s as well as in males and females, nasal height had a weak positive linear relationship with stature; r=0.283 in total students, r=0.222 for male and r=0.123 for female. The regression equation for stature and nasal height was found to be Y=134.053+0.648× nasal height for total students, Y=146.487+0.496×nasal height for males, Y=151.328+0.177× nasal height for females. Conclusion: The observed correlation is statistically significant in total students (p value<0.05) but not significant in males and females (p value>0.05). Overall nasal height had a weak positive linear correlation with stature.

Exploring the Relationship Between Serum Creatinine and Salivary Creatinine Levels in Patients With Chronic Kidney Disease in South India: A Cross-Sectional Study.

Background In this study, researchers investigated non-invasive methods for analyzing creatinine levels by using saliva to address the need for frequent phlebotomy in chronic kidney disease (CKD) patients, which can damage their veins due to repeated blood withdrawals for creatinine level assessments. Methods This is a cross-sectional study in a tertiary healthcare setting conducted on 50 patients diagnosed with CKD. After collecting serum and salivary creatinine, we used Pearson correlation to assess the correlation between the two factors. Results The mean age of the patients was 50 years with a standard deviation of ± 15.32 years. 33 (66%) patients were males and 17 (34%) were females. Most patients were in the age group of 51 - 70 years, comprising 26 (52%) of the sample. The serum creatinine and salivary creatinine values ranged between 7.26-12.00 and 0.45-0.98, respectively. The median values were 9.72 and 0.75, respectively. There was a very weak positive linear relationship between serum and salivary creatinine levels; however, there was no significant association between them (p = 0.52). Nonetheless, a statistically significant, moderately negative linear correlation exists between serum urea and serum albumin (r = -0.36; p = 0.01). Additionally, there is a statistically significant weak negative linear correlation between serum chloride and serum urea (r = -0.3; p = 0.03). Comparing serum chloride and serum sodium reveals a statistically significant, moderately positive linear relationship (r = 0.4; p = 0.004). Serum phosphorus and serum creatinine display a statistically significant moderate positive linear relationship (r = 0.44; p = 0.001). Moreover, estimated glomerular filtration rate (eGFR) and serum creatinine exhibit a statistically significant strong negative linear correlation (r = -0.79; p < 0.001), while eGFR and serum phosphorus demonstrate a statistically significant weak negative linear correlation (r = -0.30; p = 0.03). Conclusion The study found no significant association between salivary and serum creatinine levels. Further multicentric studies on a larger population must be conducted to find the potential correlation between serum and salivary markers.

Perkembangan Nilai Tukar Petani (NTP) Jawa Barat dan Korelasinya dengan Tenaga Kerja, Inflasi, dan Produk Domestik Regional Bruto (PDRB) Sektor Pertanian Jawa Barat

This research aims to identify the developments of Farmer Exchange Rate (FER) in the West Java Agricultural Sector in the period 2000-2022. This paper analyzes the extent of the correlation between Agricultural Sector Labor, the Inflation Rate variables, and the Gross Regional Domestic Product (GRDP) of Agricultural Sector on the FER in the in West Java. The correlation identification between these variables was analyzed through Pearson’s Product Moment Correlation analysis based on West Java FER. The FER data is obtained from the Farmer Exchange Rate Statistics published by the Central Statistics Agency (BPS). The research results show: a) There are variations in the FER value during the period 2005-2022 with an average of 103.99; b) The West Java Agricultural Sector Labor variable has a moderate positive linear correlation with West Java's FER; c) The West Java Agricultural Sector variable GRDP has weak negative linear correlation with West Java's FER; and d) The West Java inflation variable has a weak positive linear correlation with West Java's FER.

Elucidating the impact of ploidy level on biochemical content accumulation in haskap (Lonicera caerulea L. subsp. edulis (Turcz. ex Herder) Hultén) fruits: A comprehensive approach for fruit assessment

Artificially induced polyploidies in haskap (Lonicera caerulea L. subsp. edulis (Turcz. ex Herder) Hultén) were used in a systematic investigation to uncover the complex interplay between ploidy variations and the metabolic processes that govern the accumulation of biochemical compounds in fruits. This study used two distinct measurement units to support a rich analytical output to enhance the robustness of fruit quality evaluation substantially. Strong positive linear relationships were identified between ploidy levels and specific substances, including quinic acid and sorbitol. Conversely, several other substances had little or weak linear correlation with ploidy, underscoring that ploidy level can influence the accumulation of biochemical compounds in a substance-specific manner. This study reveals that tetraploid fruits, particularly individual accessions, demonstrate superior quality compared to other ploidy levels. This superiority is more notably pronounced when evaluated regarding content per fruit (CPF). Our findings provide key insights into the effects of ploidy on fruit quality with potential implications for future haskap breeding and cultivation practices. They also underscore the need for an in-depth understanding of the genetic and physiological factors that drive these variations. Such knowledge is crucial for strategically harnessing these variations and optimizing the quality and yield of haskap fruit production.

INFORMATIVENESS OF TRANSIENT AND TWO-DIMENSIONAL SHEAR WAVE ELASTOGRAPHY IN ASSESSING OF LIVER STIFFNESS IN POST-COVID-19 AND CARDIOHEPATIC SYNDROMES

Ultrasound elastography of diffuse liver diseases allows to assess liver stiffness and predict the further course of the disease, determine the tactics of patient’s management for post-Covid and cardiohepatic syndrome. The purpose of the research – to study the diagnostic informativeness and evaluate the correlation between one-dimensional and two-dimensional shear wave elastography technologies with elastometry in assessing liver stiffness in patients with post-COVID and cardiohepatic syndromes. Materials and methods. A comparative analysis of the information content and correlation between the results of one-dimensional and two-dimensional shear wave elastography of the liver was carried out in 85 patients with post-COVID (N1; n = 30) and cardiohepatic (N2; n = 25) syndromes. The control group (N3; n = 30) consisted of patients without the new coronavirus infection COVID-19 and without any pathology of the liver and biliary system. In the control group, the study of liver parenchyma stiffness using shear wave elastography was carried out by lobes and segments. Standard variation statistics algorithms were used, taking into account the type of data distribution in the statistical analysis. Quantitative indicators with a normal distribution were described using arithmetic means (M) and standard deviations (SD), boundaries of the 95% confidence interval (95% CI). In the absence of a normal distribution, quantitative data were described using the median (Me) and lower and upper quartiles (Q1–Q3). Research results. The stiffness values (Emean) in the projection of segments VI, VII had larger values (p = 0.02) when compared with other segments. We obtained the following Emean values in transient elastography: in the group of patients with post-COVID syndrome (N1) – 10.02 kPa; in the group of patients with chronic heart failure (N2) – 14.09 kPa, which turned out to be significantly higher than the stiffness of the liver parenchyma among healthy individuals, where the Emean value was 4.90 kPa (p = 0.05). With shear wave elastography, the results were also higher in the group of patients with chronic heart failure (N2), where Emean was 20.90 kPa, compared to the group of patients with post-COVID syndrome (N1) – 11.86 kPa. Conclusions. The results of shear wave elastography were successful in 100% of cases, the results of transient elastography in 84.6% of cases. Correlation analysis of connections in a group of patients with chronic heart failure according to TE and SWE showed a weak positive direct linear correlation. A positive direct linear correlation of medium strength was obtained in assessing the correlation in the group of patients with post-COVID syndrome.

Insulin resistance in patients suffering from severe AS

Abstract Background There are several cardiovascular risk factors known to promote the development of AS, one of them being type 2 diabetes (T2D). T2D is increasingly recognized as a heterogenous disease, leading to the latest concept of five diabetes clusters based on clinical parameters. Until now, the impact of the respective clusters, especially insulin resistance in prediabetes, on valvular cells and therefore the development of AS is not clear. Purpose We hypothesize that insulin resistance, which is frequently underrated, features a specific pattern of aortic valve calcification characterized by an elevated degree of calcification. Methods In order to analyze the impact of diabetes on AS we examined 200 patients with severe AS, scheduled for a transcatheter aortic valve implantation (TAVI). With the exemption of previously diagnosed diabetics, we performed an oral glucose tolerance test (OGTT), identifying patients with prediabetes and T2D. Additionally, blood was drawn from all included patients 2-5 days after TAVI, depicting their metabolic condition and thereby assigning them to a diabetes cluster. These findings were subsequently correlated with data from computertomography in all patients pertaining the severity of the stenosis, including the Agatston score, which illustrates the aortic valve calcium burden. Results Following the hypothesis that the extent of insulin resistance impacts the aortic valve calcification, we correlated the HOMA-IR with the Agatston score, resulting in a weak non-significant linear correlation (r=-0.129, p = 0.097, n = 166). Therefore, increased insulin resistance has not been shown to be associated with increased aortic valve calcification. Moreover, no differences in the extent of calcification between diabetic, prediabetic and non-diabetic patients could be demonstrated (F (2, 147) = 0.410, p = 0.665). However, it was clearly striking that the majority of the patients examined had already developed prediabetes or diabetes (Non-Diabetic = 7.1%, Prediabetic = 34.6%, Diabetic = 58.2%, n= 182). Conclusion Although we were able to observe an increased rate in prediabetic and diabetic patients in our AS cohort, there was no significantly elevated aortic valve calcification in patients with pronounced insulin resistance. This suggests that insulin resistance might not directly impact valvular calcification but upstream processes in valvular cells predisposing for AS since the majority of AS patients in our cohort is (pre)diabetic.

Abstract 18140: Is Socioeconomic Status Associated With a Novel Clinical Risk Prediction Score for Sudden Cardiac Death?

Introduction: Lower socioeconomic status (SES) is associated with higher risk of sudden cardiac death (SCD), but SES has not been used for SCD risk stratification. We have recently developed a novel risk score (VFRisk) for avertable SCD (8 clinical factors, 4 ECG markers, and 1 echocardiographic marker). We evaluated the association of the clinical components of the VFRisk score with SES. Hypothesis: Higher VFRisk scores will associate with lower SES. Methods: Individuals with SCD (2002-2019), were identified from a large ongoing study in a northwest US metro area (pop ~1 million). For each SCD case, a partial VFRisk score was calculated limited to the 8 clinical components (VFRisk-clinical; diabetes, HF, stroke, atrial fibrillation, COPD, history of MI, seizure, and syncope). The VFRisk-clinical score was categorized as low (&lt;25 th percentile), moderate (25 th -75 th ), and high (&gt;75 th percentile). SES was defined for each SCD case by residential census tract median household income and categorized into quintiles. Results: Among 4,412 SCD cases, data for SES and VFRisk-clinical was available for 3,606 (82%) with a median VFRisk of 2.8 (min 0 - max 13.4). There was a weak negative linear correlation between median household income quintile and VFRisk-clinical score (r = -0.05, p=0.002) and mean VFRisk-clinical score was slightly lower with higher SES quintile (Figure). However, there was no significant trend in the proportion of SCD cases with a high VFRisk-clinical score (&gt;75 th percentile) by median income quintile (p=0.13). In a logistic regression model, income quintile was not significantly associated with a high VFRisk-clinical score (p=0.60). Conclusions: No clear association was observed between the VFRisk-clinical score and SES, possibly due to involvement of SES early in the causal pathway of these clinical conditions, or due to effects of SES on risk pathways for SCD separate from the components of the VFRisk score.

Tree-Structured Parzan Estimator–Machine Learning–Ordinary Kriging: An Integration Method for Soil Ammonia Spatial Prediction in the Typical Cropland of Chinese Yellow River Delta with Sentinel-2 Remote Sensing Image and Air Quality Data

Spatial prediction of soil ammonia (NH3) plays an important role in monitoring climate warming and soil ecological health. However, traditional machine learning (ML) models do not consider optimal parameter selection and spatial autocorrelation. Here, we present an integration method (tree-structured Parzen estimator–machine learning–ordinary kriging (TPE–ML–OK)) to predict spatial variability of soil NH3 from Sentinel-2 remote sensing image and air quality data. In TPE–ML–OK, we designed the TPE search algorithm, which encourages gradient boosting decision tree (GBDT), random forest (RF), and extreme gradient boosting (XGB) models to pay more attention to the optimal hyperparameters’ high-possibility range, and then the residual ordinary kriging model is used to further improve the prediction accuracy of soil NH3 flux. We found a weak linear correlation between soil NH3 flux and environmental variables using scatter matrix correlation analysis. The optimal hyperparameters from the TPE search algorithm existed in the densest iteration region, and the TPE–XGB–OK method exhibited the highest predicted accuracy (R2 = 85.97%) for soil NH3 flux in comparison with other models. The spatial mapping results based on TPE–ML–OK methods showed that the high fluxes of soil NH3 were concentrated in the central and northeast areas, which may be influenced by rivers or soil water. The analysis result of the SHapley additive explanation (SHAP) algorithm found that the variables with the highest contribution to soil NH3 were O3, SO2, PM10, CO, and NDWI. The above results demonstrate the powerful linear–nonlinear interpretation ability between soil NH3 and environmental variables using the integration method, which can reduce the impact on agricultural nitrogen deposition and regional air quality.

Readiness of Technology and Livelihood Education Students in Taking the Licensure Examination for Teacher

The study attempted to look on to the readiness of the Technology and Livelihood Education students of the Bulacan State University Hagonoy Campus in taking the Licensure Examination for Teachers during the school year 2018-2019. The study made used of both qualitative and quantitative research. Grades of the respondents was requested to the university registrar and a standardized comprehensive examination was given to the respondents to validate their readiness in taking the board examination. A face-to-face interview was also conducted to know the problems they have encountered in taking the course and in taking the comprehensive examination. Weighted mean was computed and determine the readiness of the respondents using the Pearson R correlation. As revealed by the findings, both general weighted average and the result of the comprehensive examination registered a very weak linear correlation. In order to respond to the observations cited by the respondents the researcher suggested to provide an in-house review before taking the board examination and a strict retention policy among education students.

On Integral INICS Aromaticity of Pyridodiazepine Constitutional Isomers and Tautomers.

The structure, energetics, and aromaticity of c.a. 100 constitutional isomers and tautomers of pyrido[m,n]diazepines (m = 1, 2; n = 2, 3, 4, 5; m ≠ n) were studied at the B3LYP/cc-pVTZ level. The pyrido[1,3]diazepines appear the most, while pyrido[2,4]diazepines are the least stable (ca. 26 kcal/mol). In the pyrido[1,n]diazepine group (n = 2-5), the [1,5] isomers are higher in energy by ca. 4.5 kcal/mol and the [1,4] ones by ca. 7 kcal/mol, and the pyrido[1,2]diazepines are the least stable (ca. 20 kcal/mol). All the most stable pyrido[1,n]diazepines have N-atoms near the ring's junction bond but on opposite sites. The most stable [2,n]-forms are also those with the pyridine ring N6-atom near the junction bond. Surprisingly, for the [1,2]-, [1,3]-, and [1,4]-isomer condensation types of pyridine and diazepine rings, the same N9 > N7 > N6 > N8 stability pattern obeys. The stability remains similar in a water medium simulated with the Polarizable Continuum Model of the solvent and is conserved when calculated using the CAM-B3LYP or BHandHlyp functionals. The ring's aromaticity in the pyridine[m,n]diazepines was established based on the integral INICS index resulting from the NICSzz-scan curves' integration. The integral INICS index is physically justified through its relation to the ringcurrent as demonstrated by Berger, R.J.F., et al. Phys. Chem. Chem. Phys. 2022, 24, 624. The six-membered pyrido rings have negative INICSZZ indices and can be aromatic only if they are not protonated at the N-atom. All protonated pyrido and seven-membered rings exhibit meaningful positive INICSZZ values and can be assigned as antiaromatic. However, some non-protonated pyrido rings also have substantial positive INICSZZ indices and are antiaromatic. A weak linear correlation (R2 = 0.72) between the INICSZZ values of the pyridine I(6) and diazepine I(7) rings exists and is a consequence of the communication between the π-electron systems of the two rings. The juxtaposition of the INICS descriptor of the six- and seven-membered rings and diverse electron density parameters at the Ring Critical Points (RCP) revealed good correlations only with the Electrostatic Potentials from the electrons and nuclei (ESPe and ESPn). The relationships with other RCP parameters like electron density and its Laplacian, total energy, and the Hamiltonian form of kinetic energy density were split into two parts: one nearly constant for the six-membered rings and one linearly correlating for the seven-membered rings. Thus, most of the electron density parameters at the RCP of the six-membered rings of pyridodiazepines practically do not change with the diazepine type and the labile proton position. In contrast, those of the seven-membered rings display aromaticity changes in the antiaromatic diazepine with its ring structural modifications.

Comparison of magnetic susceptibility probes relevantly used in soil contamination applications.

Magnetic susceptibility (MS) technology can achieve the efficient rough measurement, mapping, and pollution assessment of soil heavy metal concentrations in topsoil due to atmospheric dust contamination. However, previous studies of commonly used MS field probes (MS2D, MS2F, and MS2K) have not dealt with the range of magnetic signal detection and the attenuation characteristics of the signal with respect to distance. In this study, the vertical and horizontal measurement ranges of the MS2D, MS2F, and MS2K probes were explored through laboratory and field experiments, and the intensity of their magnetic signals was further compared and analyzed in the field. The results showed that the magnetic signal intensity of the three probes decreased exponentially with distance. The penetration depths of the MS2D, MS2F, and MS2K probes were 8.5, 2.4, and 3.0cm, respectively, and the horizontal detection boundary lengths of their magnetic signals were 32, 8, and 6.8cm, respectively. In the field surface soil MS detection, the magnetic measurement signals of the MS2F and MS2K probes showed a weak linear correlation with the MS2D probe (R2 of 0.43 and 0.50, respectively), while the MS2F and MS2K probes had a significantly better correlation (R2 = 0.68) with each other. In general, the MS2D probe and MS2K probe correlation had a slope close to unity, meaning MS2K probes had good mutual substitution. Furthermore, results of this study improve the effectiveness of the MS evaluation of heavy metal pollution in urban topsoil.

Prediction of NH3 and HCN yield from biomass fast pyrolysis: Machine learning modeling and evaluation

Rapid pyrolysis is a promising technique to convert biomass into fuel oil, where NOX emission remains a substantial environmental risk. NH3 and HCN are top precursors for NOX emission. In order to clarify their migration path and provide appropriate strategies for their controlling, six up-to-date machine learning (ML) models were established to predict the NH3 and HCN yield during rapid pyrolysis of 26 biomass feedstocks. Cross-validation and grid search methods were used to determine the optimal hyperparameters for these ML models. The support vector regression (SVR) model achieved optimal accuracy among them. The optimal root means square error (%), mean absolute error (%), and R2 of test set for NH3/HCN yield were 1.2901/1.1531, 1.0501/0.84712, and 0.98253/0.96152, respectively. In addition, based on the results of Pearson correlation analysis, the input variables with a weak linear correlation with the target product were eliminated, which was found capable of improving the prediction accuracy of almost all ML models except SVR. While after input variables elimination, the SVR model still showed the optimal NH3 and HCN yield prediction accuracy. It reflects SVR's great significance and potential for predicting the yield of NOX precursors during rapid biomass pyrolysis.

A CROSS-SECTIONAL STUDY ON CORRELATION BETWEEN SERUM URIC ACID LEVEL AND CAROTID ATHEROSCLEROSIS IN PATIENTS OF TYPE 2 DIABETES

Objective: The objective of the study was to assess correlation between uric acid (UA) level and carotid intima media thickness (CIMT) in type 2 diabetes mellitus (DM) patients. Methods: The study was conducted in the Department of Medicine, SMS Medical College and Attached Hospital, among adults with type 2 DM. It was cross-sectional study conducted from April 1, 2019, to December 31, 2020. Sample size is calculated 60 patients of Type 2 DM. As per previous study show correlation coefficient between serum UA (SUA) level and CIMT (r=0.779)52 (For 90% power and 1% α error). CIMT and carotid artery plaques were measured through Doppler ultrasound. The thickness was measured at 1 cm proximal to the dilatation of the carotid bulb. The mean of maximum IMT of both the common carotid artery is taken as the average CIMT. Results: Most patients (60%) were diabetics since 5 years and nearly 30% had diabetes since 5–15 years while only 10% had diabetes since more than 15 years. Mean duration of diabetes was 6.91±5.88 years. Two thirds of diabetic individuals (67%) had HDL cholesterol level above 40 mg/dL. About 42% of diabetic individuals had triglyceride level &lt;150 mg/dL and 5% of diabetic individuals had LDL cholesterol level &lt;100 mg/dL. Mean HDL cholesterol, Triglycerides, and LDL cholesterol were 47.4±15.49 mg/dL, 153.78±81.56 mg/dL, and 92.33±57.28 mg/dL, respectively. Mean bilirubin and serum creatinine in study population were 0.65±0.48 mg/dL and 0.96±0.18 mg/dL, respectively. Mean CRP was 3.95±2.40 mg/L. Mean SUA level in study population was 5.78±2.18 mg/dL. Mean of average CIMT was found to be 8.0±1.16 mm. Glycated hemoglobin (HbA1c) and UA had negative weak linear correlation which was statistically significant. HbA1c and average CIMT had no or week negative correlation which was not statistically significant and SUA and average CIMT showed positive moderate linear correlation which was statistically significant. Conclusion: Carotid atherosclerosis as measured by IMT is associated with SUA levels in patients with type 2 DM. In type 2 DM patients, HbA1C is negatively correlated with UA while HbA1C has no correlation with CIMT.

Objective structured clinical examination: Do first-year nursing students perceive it to be stressful?

The Objective Structured Clinical Examination (OSCE) is widely accepted as an effective means of assessing clinical competence and nursing skills. There is, however, little existing knowledge on how first-year nursing students perceived stress during their first OSCE. To determine the perception of stress; to identify the perceived factors causing stress; and to determine the perceived incidence of stress. A descriptive, survey was conducted on a sample of 82 first-year nursing students using the Perceived Stress Scale (PPS). The results showed that more than half (n= 54) of students perceived stress at moderate levels. Students not having sufficient time to complete the OSCE was perceived as the main factor causing stress (mean = 22.04; standard deviation [s.d.] = 6.21). The correlation between perception of stress and perceived factors causing stress showed a significant weak positive linear correlation among the variables (r= 0.45;p 0.05). The study findings are important as the data determining the first-year nursing students' perception of stress were collected immediately after their first OSCE, which may indicate that perception of stress was related to the actual event rather than the preparation for the OSCE. A follow-up qualitative research study should be conducted, preferably in the same setting, so that the students' experiences of stress during the first OSCE can be explored in depth.

Skeletal standardized uptake values obtained using quantitative SPECT/CT for the detection of bone metastases in patients with lung adenocarcinoma.

To assess the utility of skeletal standardized uptake values (SUVs) obtained using quantitative single-photon emission computed tomography/computed tomography (SPECT/CT) in differentiating bone metastases from benign lesions, particularly in patients with lung adenocarcinoma. Patients with lung adenocarcinoma who had undergone whole-body Tc-99m methyl-diphosphonate (99mTc-MDP) bone scans and received late phase SPECT/CT were retrospectively analyzed in this study. The maximum SUV (SUVmax); Hounsfield units (HUs); and volumes of osteoblastic, osteolytic, mixed, CT-negative metastatic and benign bone lesions, and normal vertebrae were compared. Receiver operating characteristic curves were used to determine the optimal cutoff SUVmax between metastatic and benign lesions as well as the cutoff SUVmax between CT-negative metastatic lesions and normal vertebrae. The linear correlation between SUVmax and HUs of metastatic lesions as well as that between SUVmax and the volume of all bone lesions were investigated. A total of 252 bone metastatic lesions, 140 benign bone lesions, and 199 normal vertebrae from 115 patients with lung adenocarcinoma were studied (48 males, 67 females, median age: 59 years). Metastatic lesions had a significantly higher SUVmax (23.85 ± 14.34) than benign lesions (9.67 ± 7.47) and normal vertebrae (6.19 ± 1.46; P < 0.0001). The SPECT/CT hotspot of patients with bone metastases could be distinguished from benign lesions using a cutoff SUVmax of 11.10, with a sensitivity of 87.70% and a specificity of 80.71%. The SUVmax of osteoblastic (29.16 ± 16.63) and mixed (26.62 ± 14.97) lesions was significantly greater than that of osteolytic (15.79 ± 5.57) and CT-negative (16.51 ± 6.93) lesions (P < 0.0001, P = 0.0003, and 0.002). SUVmax at the cutoff value of 8.135 could distinguish CT-negative bone metastases from normal vertebrae, with a sensitivity of 100.00% and a specificity of 91.96%. SUVmax showed a weak positive linear correlation with HUs in all bone metastases and the volume of all bone lesions. SUVmax of quantitative SPECT/CT is a useful index for distinguishing benign bone lesions from bone metastases in patients with lung adenocarcinoma, particularly in the diagnosis of CT-negative bone metastases, but other factors that may affect SUVmax should be considered.

Objective structured clinical examination: Do first-year nursing students perceive it to be stressful?

Background: The Objective Structured Clinical Examination (OSCE) is widely accepted as an effective means of assessing clinical competence and nursing skills. There is, however, little existing knowledge on how first-year nursing students perceived stress during their first OSCE. Objectives: To determine the perception of stress; to identify the perceived factors causing stress; and to determine the perceived incidence of stress. Method: A descriptive, survey was conducted on a sample of 82 first-year nursing students using the Perceived Stress Scale (PPS). Results: The results showed that more than half ( n = 54) of students perceived stress at moderate levels. Students not having sufficient time to complete the OSCE was perceived as the main factor causing stress (mean = 22.04; standard deviation [s.d.] = 6.21). The correlation between perception of stress and perceived factors causing stress showed a significant weak positive linear correlation among the variables ( r = 0.45; p &lt; 0.05). Conclusion: The study findings are important as the data determining the first-year nursing students’ perception of stress were collected immediately after their first OSCE, which may indicate that perception of stress was related to the actual event rather than the preparation for the OSCE. A follow-up qualitative research study should be conducted, preferably in the same setting, so that the students’ experiences of stress during the first OSCE can be explored in depth.