Dose‒Response Effects of Patient Engagement on Anxiety and Depression in a Cognitive-Behavioral Intervention: Secondary Analysis of a Pilot Randomized Controlled Trial and a Clinical Controlled Trial.

Understanding the dose‒response relationship between patient engagement in cognitive behavioral therapy (CBT) and health outcomes is critical for developing and implementing effective CBT programs. In studies of CBT interventions, patient engagement is measured only at a single time point, and outcomes are typically assessed before and after the intervention. Examination of the dose‒response relationship between patient engagement in CBT and outcomes is limited. It is unclear whether a dose‒response relationship exists between patient engagement in on-site CBT intervention and anxiety and depression in people living with HIV (PLWH). If present, does this dose‒response relationship occur early or later in the intervention? This study aimed to address this gap by examining the dose‒response relationships between patient engagement and anxiety and depression in CBT interventions among PLWH. Utilizing data from a pilot randomized trial (10 participants) and a clinical controlled trial (70 participants), our secondary analysis spans baseline, 3-month, and 6-month assessments. Both trials implemented the nurse-led CBT intervention. Cluster analysis identified two groups based on on-site attendance and WeChat activity. Patients with good adherence (6-10 times) of on-site attendance exhibited significantly lower anxiety and depression scores at 3 months (ß = 1.220, P = 0.047; ß = 1.270, P = 0.019), with no significant differences observed at 6 months. WeChat activity did not significantly influence anxiety or depression scores. The findings highlight a significant short-term dose‒response relationship, endorsing nurse-led CBT interventions for mental health in PLWH. Organizational strategies should focus on incentivizing and facilitating patient engagement, particularly through enhancing WeChat features.

Suffering and adjustment: a grounded theory of the process of coping with financial toxicity among young women with breast cancer.

PURPOSE: To explore the process of coping with financial toxicity among young women with breast cancer and formulate a grounded theory that serves as a foundation for creating intervention strategies aimed at supporting cancer survivors. METHODS: A qualitative study using the Corbin and Strauss variant of grounded theory. A series of in-depth interviews were carried out with young women with breast cancer (n = 29) using the theoretical sampling method. We analyzed data by coding core categories in the patients' coping processes and developing theory around these categories. Data collection and analysis were performed simultaneously. RESULTS: A substantial theory of the process of coping with financial toxicity among young female breast cancer survivors was constructed. Two core concepts, suffering and adjustment, were identified. Young women with breast cancer suffered from financial toxicity, which was related to risk factors, coping resources, and unmet needs. To overcome financial toxicity, young women with breast cancer adjusted by reshaping consumption concept, re-dividing of family functions, re-planning of occupation career, and rebuilding life confidence. CONCLUSION: This qualitative study constructed a theory delineating the coping strategies employed by young women with breast cancer in response to financial toxicity, offering profound insights into the intricacies of cancer-related financial toxicity. Identifying risk factors, enhancing coping resources, and meeting unmet needs would be helpful to patients' adjustment to financial stress.

Identification of factors driving the spatial distribution of molybdenum (Mo) in topsoil in the Longitudinal Range-Gorge Region of Southwestern China using the Geodetector model.

As a key component of plant nitrogen-fixing enzymes and a variety of human coenzyme factors, molybdenum (Mo) plays an essential role in supporting both plant growth and human health. Soil is a key medium for the cycling of Mo in the biosphere. However, the driving anthropogenic and natural factors governing the spatial distribution of Mo in soil and their interactions are not well understood. To determine the factors that affect the spatial patterns of Mo in topsoil, 6980 samples were collected from the Longitudinal Range-Gorge Region (Linshui County, Sichuan Province, China). In this area, tall mountains are adjacent to deep valleys. Topsoil with enriched Mo is mostly distributed in mountainous areas. The most important factors influencing Mo in topsoil are soil parent materials (q = 0.482), altitude (q = 0.256), and soil type (q = 0.259). There are synergistic effects among the various driving factors [q(X1 âˆ© X2) > Max[q(X1), q(X2)]]. The Geodetector model was used to validate the magnitude of the interaction effects. The contribution to interacting factors is nonlinearly enhanced when the contribution of a single factor was low (any two factors of aspect, road distance, land use type, and S). The contribution to interacting factors is enhanced bidirectionally when the contribution of a single factor was high (any two factors of altitude, soil type, soil parent material, OM, and TFe2O3). When the contribution of one factor is high and the other is low, the contributing to interacting factors is mostly enhanced bidirectionally and a few are nonlinearly enhanced.

Enrichment mechanisms of Mo in soil in the karst region Guangxi, China.

Soils developed in karst regions have naturally high background values of molybdenum (Mo) due to geological factors. However, the enrichment mechanism of Mo in these soils are not fully understood, making it challenging to assess their ecological risk and utilize Mo-rich land resources. To shed light on this issue, this study collected and analyzed data from the 1:50,000 geochemical survey in Guangxi, including 536,503 sets of soil data and 3043 sets of rock data, as well as 40 sets of carbonate rock-soil from typical karst regions. The results showed that soil Mo enrichment is highly correlated with the distribution of carbonate rocks in karst regions. The carbonate rocks in these regions contain Mo ranging from 0.03 to 1.06 mg·kg-1 (with a mean of 0.22 mg·kg-1). In comparison, the soil Mo derived from carbonate rocks can reach up to 6.00 mg·kg-1 (with a mean of 2.75 mg·kg-1), representing an average enrichment of soil Mo that is 24 times higher compared to the carbonate parent rock. The enrichment of soil Mo in karst regions is primarily controlled by secondary enrichment during the weathering process of carbonate. During the insoluble residue accumulation process, the dissolution of carbonate leads to a dramatic reduction in bedrock volume, and the adsorption of clay minerals and Fe minerals in insoluble residues plays an essential role in Mo enrichment during these stages. During the soil-forming stage of the insoluble residue, most Mo leaches into the water body due to the mineral transformation of insoluble residue. Consequently, as Fe-Mn nodules in soils become more enriched with increasing weathering intensity, some Mo is absorbed and passivated by iron and manganese oxides (hydroxides). Accordingly, the contribution of Fe-Mn nodules and the degree of leaching were closely related to the enrichment of soil Mo in karst regions. This study provides insights into the enrichment mechanisms of Mo in soils developed in karst regions, which will help to evaluate their ecological risk in these environments.

Linking health to geology-a new assessment and zoning model based on the frame of medical geology.

With the growing concerns about the Earth's environment and human health, there has been a surge in research focused on the intersection of health and geology. This study quantitatively assesses the relationship between human health and geological factors using a new framework. The framework considers four key geological environment indicators related to health: soil, water, geological landform, and atmosphere. Results indicate that the atmospheric and water resource indicators in the study area were generally favorable, while the scores of geological landforms varied based on topography. The study also found that the selenium content in the soil greatly exceeded the local background value. Our research underscores the importance of geological factors on human health, establishes a new health-geological assessment model, and provides a scientific foundation for local spatial planning, water resource development, and land resource management. However, due to varying geological conditions worldwide, the framework and indicators for health geology may need to be adjusted accordingly.

Identification of high ecological risk areas with naturally high background value of soil Cd related to carbonate rocks.

The characteristics of high concentrations or high activity levels of heavy metals, especially Cd, in soils caused by the pedogenesis of rocks are attracting increased attention. Carbonate rocks and black shales often coexist during geological deposition, but the risk characteristics of heavy metals are different after their weathering into the soil. The purpose of this study was to investigate the element concentrations of a naturally high background value area, to identify patterns of different risk areas, and to make recommendations for the safe usage of farmland. The results showed that, compared with the soil in the carbonate rock area, the soil in the black shale area was more acidified and most of the heavy metal elements were leached. Based on the soil pH value and the heavy metal concentrations, an identification method for land risk areas within naturally high background values was established, and land planning was carried out using this method. The exceeding rates of Cd in rice for the preferential protection area and strict control area were 0.0 and 50.0%, respectively. Therefore, in naturally high background area, the identified lithology can apply to maximize the use of farmland resources. This method provides a basis for preliminary ecological risk screening in naturally high background value areas using the results of the soil survey. A suggestion for the prevention and control of soil pollution in areas with naturally high background values was put forward. In carbonate rock areas, the soil should be closely monitored to prevent soil acidification.

Identification of the spatial patterns and controlling factors of Se in soil and rice in Guangxi through hot spot analysis.

Selenium (Se) is essential to human health, anti-cancer, possessing antioxidant, and antiviral properties. In this study, the spatial patterns of rice Se and their varying relationship with soil Se on a regional scale were studied using hot spot analysis for the agricultural soils in Guangxi. According to the hot and cold spot maps, rice Se correlates positively with soil Se in Guangxi agricultural soils. High rice Se accompanies high soil Se in the central part of Guangxi (e.g., Liuzhou, Laibin), and low rice Se is in line with low soil Se in the western part (e.g., Baise). However, the hot spot analysis maps indicate that southwestern Guangxi exhibits a special characteristic of low rice Se with high soil Se (e.g., Chongzuo). This special pattern is strongly associated with the high concentrations of Fe2O3 (ferromanganese nodules) in the carbonate rock area. The hot spot analysis proves useful in revealing the spatial patterns of rice Se in Guangxi and identifying the hidden patterns.

Psychometric properties of self-reported measures of health-related quality of life in people living with HIV: a systematic review.

OBJECTIVE: To identify and assess the psychometric properties of patient-reported outcome measures (PROMs) of health-related quality of life (HRQoL) in people living with HIV (PLWH). METHODS: Nine databases were searched from January 1996 to October 2020. Methodological quality was assessed by using the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) Risk of Bias Checklist. We used the COSMIN criteria to summarize and rate the psychometric properties of each PROM. A modified Grading, Recommendations, Assessment, Development, and Evaluation (GRADE) system was used to assess the certainty of evidence. RESULTS: Sixty-nine studies reported on the psychometric properties of 30 identified instruments. All studies were considered to have adequate methodological quality in terms of content validity, construct validity, and internal consistency. Limited information was retrieved on cross-cultural validity, criterion validity, reliability, hypothesis testing, and responsiveness. High-quality evidence on psychometric properties was provided for the Medical Outcomes Study HIV Health Survey (MOS-HIV), the brief version of the World Health Organization's Quality of Life Instrument in HIV Infection (WHOQoL-HIV-BREF), 36-Item Short Form Survey (SF-36), Multidimensional Quality of Life Questionnaire for Persons with HIV/AIDS (MQoL-HIV), and WHOQoL-HIV. CONCLUSIONS: The findings from the included studies highlighted that among HIV-specific and generic HRQoL PROMs, MOS-HIV, WHOQoL-HIV-BREF, SF-36, MQoL-HIV, and WHOQoL-HIV are strongly recommended to evaluate HRQoL in PLWH in research and clinics based on the specific aims of assessments and the response burden for participants.

Experience of chronic noncommunicable disease in people living with HIV: a systematic review and meta-aggregation of qualitative studies.

BACKGROUND: An increasing number of people living with HIV (PLWH) have had chronic noncommunicable diseases (NCDs) over the last 5 years. However, robust evidence regarding the perception and challenges of having NCDs among PLWH is limited. Therefore, this study aimed to synthesize qualitative evidence regarding the experiences of PLWH with NCDs. METHODS: We used a meta-aggregation approach to synthesize qualitative studies. Peer-reviewed and gray literature published in English and Chinese from 1996 to November 2020 was searched using electronic databases. Two reviewers independently appraised the methodological quality and extracted data from the included studies. The Joanna Briggs Institute (JBI) meta-aggregation approach was used to synthesize the findings. RESULTS: In total, 10,594 studies were identified in the initial database search. Fourteen eligible studies were included in the meta-synthesis. Among these studies, nine synthesized findings regarding the following topics were identified: fragmented healthcare systems, care continuity, manifestations of multiple conditions, financial hardship, stigma and discrimination, polypharmacy burden and adherence, reciprocal relationships between HIV and NCDs, and coping strategies. CONCLUSIONS: In recent years, attempts have been made to institutionalize NCD preventive and control services in HIV long-term care. However, considering the growing problem of HIV and NCD comorbidity globally, integrated primary health care systems are needed to address the problems of PLWH with NCDs. Healthcare professionals should help PLWH develop strategies to better monitor their polypharmacy burden and adherence, stigma and discrimination, financial hardship, and manifestations of multiple conditions to achieve high levels of care continuity.

Study on safe usage of agricultural land in karst and non-karst areas based on soil Cd and prediction of Cd in rice: A case study of Heng County, Guangxi.

It is well-known that Cd concentration in the soil, Cd bioavailability, and Cd bioaccumulation in rice (Oryza sativa L.) grains vary greatly in different soil parent materials. Therefore, the classification of agricultural land environmental quality and agricultural land safe usage based on the Cd content in the soil has a wide deviation. By the application of systematic sampling and analysis of soil and rice samples, and in comparison with the different soil parent materials in Heng County, it was found that soil derived from carbonate rocks has higher total Cd and lower mobile Cd proportion than soil from the non-karst areas. This result indicated that soil carbonates raised soil pH and the adsorption of Fe/Mn oxide/hydroxide on Cd significantly reduced the bioavailability of Cd in karst areas. In contrast, acidic soils with relatively lower CaO, TFe2O3, Mn and total Cd contents, the grown rice plants accumulated higher Cd in their grains. Further research confirmed significant differences in Cd bioaccumulation abilities in the soil between karst and non-karst areas. On this basis, the bioaccumulation factor prediction models of Cd in rice grains were developed in karst and non-karst areas. According to the total concentration of Cd in topsoil samples obtained from the area survey and the predicted Cd content in rice grains, an agricultural land safe usage scheme was put forward. The results showed that the agricultural land classification method based on Cd concentration in the soil and rice grains was more accurate and scientific than that based on the Cd contents in the soil alone.

Transfer mechanism and bioaccumulation risk of potentially toxic elements in soil-rice systems comparing different soil parent materials.

Although the accumulation of potentially toxic elements in soil and crops has attracted widespread attention, the characteristics of the transfer and accumulation of potentially toxic elements in soil-crop systems with different soil parent materials are still not clear. Soil and crop samples were collected from agricultural regions with different soil parent materials in Guangxi, China. This study analyzed the concentrations of Cd, Zn, and Fe in the roots, straws, and seeds of rice (Oryza sativa L.) and soils with Quaternary sediments and clastic rocks as the parent materials. The concentration of several potentially toxic elements in rice tissue from the two areas followed the order of Croot> Cstraw> Cseed. The transport capability of Cd and Zn from roots to straws is higher than straws to seeds, and Fe showed a strong capability for transport from straws to seeds. In general, the transfer capacity of potentially toxic elements in the soil-rice system in the Quaternary sediments area was stronger than that in the soil-rice system in the clastic rocks area. Soil pH and minerals, which were represented by major elements, were the main factors affecting the transfer of metals from soil to seeds. This approach could help to evaluate the bioaccumulation risk of potentially toxic elements in crops in different areas quantitatively.

Effects of Soil pH and Mineral Nutrients on Cadmium Uptake by Rice Grain in the Pearl River Delta, China.

Alluvial soils are rich in mineral nutrients, and contain high heavy metals, especially Cd. The interactions of mineral nutrients with Cd in soil-rice grain systems on natural condition of alluvial plain are highlighted in this study. 110 pairs of rice grain and soil (0-20 cm) samples from the Pearl River Delta were investigated and measured. The results indicated that pH, organic matter, cation exchange capacity, clay, Ca, Cd, Fe, Mn and Zn are the most important soil characteristics controlling Cd uptake by rice grain. There are synergetic interactions between Cd and mineral elements in the soils, and antagonistic interactions between them in the rice grains. It could provide useful information for the risk assessment of heavy metals in the soils of alluvial plain.

Potential Ecological Risk Assessment of Heavy Metals in the Fe-Mn Nodules in the Karst Area of Guangxi, Southwest China.

We investigated the concentration of heavy metals in the Fe-Mn nodules in soils derived from the carbonate rocks of typical karst areas in Guangxi, Southwest China. Compared with the soil background values in Guangxi, heavy metals are substantially enriched in the following order: Cd (268.13) > Pb (39.46) > Cr (11.80) > Zn (8.43) > Ni (6.16) > Cu (3.65). CaCl2 extraction results indicate that heavy metals in the nodules are substantially stable, while the proportions of the metals released to the surrounding environment are extremely low (≤ 0.003%). Moreover, pH-static leaching experiments indicate that heavy metals can hardly be dissolved into the surrounding soil environment under natural conditions (pH 6-8). However, once the soil environment is acidified, heavy metals incorporated in the nodules will gradually release into the surrounding environment, thereby causing potential ecological risks.

Soil Threshold Values for Zn Based on Soil-Rice System and Health Risk Assessment in a Typical Carbonate Area of Guangxi.

Zinc (Zn) is enriched in carbonate area related to geological genesis. To ensure safety of rice, soil threshold values of Zn in soil-rice systems were assessed based on analysis of soil-rice Zn concentration in relation to human health risk. Models for the prediction of Zn concentration of early-season and late-season rice grain were accurately established on the basis of significant partial correlations between log10 (BAFs) and log10 (soil properties). The rice threshold value ranged from 10.67 to 37.90 mg/kg, which might not suitable for male and urban residents. The soil safety threshold of early-season rice and late-season rice in carbonate area ranged from 148-200 mg/kg, 119-200 mg/kg with pH below 6.5, 148-250 mg/kg, 119-250 mg/kg with pH ranging from 6.5 to 7.5; 148-300 mg/kg, 119-300 mg/kg with pH above 7.5, respectively.

Safe utilization and zoning on natural selenium-rich land resources: a case study of the typical area in Enshi County, China.

Selenium (Se) is an essential trace element. However, Se in soil is often accompanied by heavy metals, such as cadmium (Cd), because of geological background. The safe utilization of such Se-rich land resources remains a challenge. A typical Se-rich area located in Enshi County, China, was systematically investigated with geochemical and epidemiological methods. The results show that Se in the topsoil is 0.84 ± 1.39 µg/g, whereas that of Cd is 0.93 ± 1.63 µg/g. And the concentration of Se and Cd in corn is 0.22 ± 0.96 µg/g and 0.15 ± 0.32 µg/g, respectively, which is mainly related to the high concentrations in soil. The benchmark dose limit of urinary Cd for ß2-microglobulin in subjects (n = 160) was calculated as 3.27 µg/g Cr. In view of crop-human dose effect and combining the relationship among the concentrations of crops and human biomarkers and the concentrations of crops and topsoil, this study established the models of land resource safety zoning. With that, the risk screening value of Cd in the soil could be obtained as 0.98 µg/g in this typical area. The proportions of priority utilization, safe utilization, and strict management of agricultural land area were 58.85%, 22.90%, and 18.25%, respectively, in Enshi, China. These results could provide scientific support for local agricultural development and ecological sustainability.

Application of ecogeochemical prediction model to safely exploit seleniferous soil.

Seleniferous soil and crops have recently attracted attention worldwide. Cultivating seleniferous crops in the absence of heavy metals is greatly challenging. This study aimed to develop approaches for the safe exploitation of seleniferous soil. We collected 246 pairs of rice grain samples and their corresponding rhizosphere soil samples and 8542 topsoil samples from Binyang and Xingbin in Guangxi. The Cd, Cu, Hg, Pb, Zn, and Se contents of soil and rice grain samples were tested. Several soil properties, including CaO, Mn, Mo, and S contents; total organic carbon content; and pH were also measured. Soil and rice grain samples that were classified as seleniferous accounted for 85.77% and 88% of all samples, respectively. More than 30% of soil and rice grain samples were potentially polluted by Cd. The percentage of seleniferous rice grain samples increased as soil Se concentration increased. Notably, however, the percentage of Cd-polluted rice grain samples decreased with the increase in soil Cd concentration. Models for the prediction of BAFs of heavy metal and Se were accurately established on the basis of significant partial correlations between log10 (BAFs) and log10 (soil properties). Farmlands with seleniferous soil under preferential protection and with safely exploited seleniferous soil accounted for 82.61% of the total study area. Sites that require remediation or land-use changes accounted for only 14.7% of the total study area and were mainly distributed in the center of the study area.

Isolation and Functional Characterization of a Phenylalanine Ammonia-Lyase Gene (SsPAL1) from Coleus (Solenostemon scutellarioides (L.) Codd).

Phenylalanine ammonia-lyase (PAL) is the first enzyme involved in the phenylpropanoid pathway and plays important roles in the secondary metabolisms, development and defense of plants. To study the molecular function of PAL in anthocyanin synthesis of Coleus (Solenostemon scutellarioides (L.) Codd), a Coleus PAL gene designated as SsPAL1 was cloned and characterized using a degenerate oligonucleotide primer PCR and RACE method. The full-length SsPAL1 was 2450 bp in size and consisted of one intron and two exons encoding a polypeptide of 711 amino acids. The deduced SsPAL1 protein showed high identities and structural similarities with other functional plant PAL proteins. A series of putative cis-acting elements involved in transcriptional regulation, light and stress responsiveness were found in the upstream regulatory sequence of SsPAL1. Transcription pattern analysis indicated that SsPAL1 was constitutively expressed in all tissues examined and was enhanced by light and different abiotic factors. The recombinant SsPAL1 protein exhibited high PAL activity, at optimal conditions of 60 °C and pH 8.2. Although the levels of total PAL activity and total anthocyanin concentration have a similar variation trend in different Coleus cultivars, there was no significant correlation between them (r = 0.7529, p > 0.1), suggesting that PAL was not the rate-limiting enzyme for the downstream anthocyanin biosynthetic branch in Coleus. This study enables us to further understand the role of SsPAL1 in the phenylpropanoid (flavonoids, anthocyanins) biosynthesis in Coleus at the molecular level.

Exploring Stigma Experience and Coping Strategies Among Women Living with HIV/AIDS in China: A Phenomenological Study.

Purpose: As of the end of 2022, over 20 million women worldwide, aged 15 and above, are living with HIV. Stigma remains a formidable barrier for women living with HIV/AIDS, hindering their access to healthcare and exacerbating health disparities. Indeed, some women living with HIV/AIDS can successfully confront and overcome stigma. There remains a paucity of qualitative research exploring the stigma coping strategies of women living with HIV/AIDS in China. This study was aimed to gain the deeper understanding of stigma experienced by women living with HIV/AIDS and coping strategies. Patients and Methods: We recruited diverse participants using snowball sampling and purposive sampling. Semi-structured personal in-depth interviews were conducted with 30 women living with HIV/AIDS from December 2022 to June 2023. The samples were from four HIV/AIDS designated hospitals. The data were analyzed using the Colaizzi seven-step model. Results: The experiences of stigma among women living with HIV/AIDS included family role (wife/mother/grandmother) collapse and disgusted by family, resignation in being shunned by others, helplessness due to social exclusion, grief at being devaluated, and resentment for experiencing injustice. The coping strategies used to deal with stigma included concealing their conditions, avoiding socialization, and attempting to retaliate against society. Conclusion: Healthcare professionals are recommended to offer women living with HIV/AIDS effective emotional support and guidance to cope with stigma. The study highlights the stigma they face, providing valuable evidence for policymakers. Recommendations emphasize the importance of developing services addressing both physical and psychological needs of women living with HIV/AIDS.

Using machine learning to predict selenium and cadmium contents in rice grains from black shale-distributed farmland area.

Cadmium (Cd) and selenium (Se) are widely enriched in soil at black shale outcropping areas, with Cd levels exceeding the standard (2.0 mg/kg in 5.5 < pH ≤ 6.5) commonly. The prevention of Cd hazards and the safe development of Se-rich land resources are key issues that need to be urgently addressed. To ensure safe utilization of Se-rich land in the CdSe coexisting areas, 158 rice samples, their corresponding rhizosphere soils, and 8069 topsoil samples were collected and tested in the paddy fields of Ankang City, Shaanxi Province, where black shales are widely exposed. The results showed that 43 % of the topsoil samples were Se-rich soil (Se > 0.4 mg/kg) wherein 79 % and 3 % of Cd concentrations exceeded the screening value and control value, respectively, according to the GB15618-2018 standard. Meanwhile, 63 % of the rice samples were Se rich (Se > 0.04 mg/kg) and the Cd content exceeded the prescribed limit (0.2 mg/kg) in Se-rich rice by 26 %. There was no significant positive correlation between the Se and Cd contents in the rice grains and the Se and Cd contents in the corresponding rhizosphere soil. The factors influencing Se and Cd uptake in rice were SiO2, CaO, P, S, pH, and TFe2O3. Accordingly, an artificial neural network (ANN) and multiple linear regression model (MLR) were used to predict Cd and Se bioaccumulation in rice grains. The stability and accuracy of the ANN model were better than those of the MLR model. Based on survey data and the prediction results of the ANN model, a safe planting zoning of Se-rich rice was proposed, which provided a reference for the scientific planning of land resources.

Influencing factors of selenium transformation in a soil-rice system and prediction of selenium content in rice seeds: a case study in Ninghua County, Fujian Province.

Selenium (Se) is an essential element for human and animal health and has antioxidant, anticancer, and antiviral effects. However, more than 100 million people in China do not have enough Se in their diets, resulting in a state of low Se in the human body. Since the absorption of Se by crop seeds depends not only on the Se content in soil, there are many omissions and misjudgments in the division of Se-rich producing areas. Soil pH, total iron oxide content (TFe2O3), soil organic matter (SOM), and P and S contents were the main factors affecting Se migration and transformation in the soil-rice system. In this study, we compared the performance of the back propagation neural network (BP network) and multiple linear regression (MLR) using 177 pairs of soil-rice samples. Our results showed that the BP network had higher accuracy than MLR. The accuracy and precision of the prediction data met the requirements, and the prediction data were reliable. Based on the Se data of surface paddy fields, 26,900 ha of Se-rich rice planting area was planned using this model, accounting for 77% of the paddy field area. In the planned Se-rich area for rice, the proportion of soil Se content greater than 0.4 mg·kg-1 was only 5.29%. Our research is of great significance for the development of Se-rich lands.