OBJECTIVE To systematically review the current application of discrete choice experiment （DCE） in the value assessment and preference measurement of orphan medicinal product （OMP）， and to provide a reference for the standardized use of this methodology in China. METHODS The systematic search was conducted across Chinese and English databases including CNKI， Wanfang Data， VIP， CBM， PubMed， Web of Science， Medline， and Embase. Original studies that employed DCE to evaluate the value or preferences related to OMP were included. The methodological quality and reporting completeness of the included studies were assessed using the ISPOR Conjoint Analysis Checklist and the DIRECT Checklist， respectively. Respondent populations， attribute setting， and the relative importance of attributes were summarized and analyzed. RESULTS Eight eligible studies were included； all studies demonstrated high-quality reporting and methodological rigor. Respondents comprised the general public， patients/caregivers， policymakers， and other stakeholders. The number of DCE attributes ranged from 4 to 13 （median＝7.5）. Through thematic synthesis， these attributes were categorized into three dimensions， namely “disease-related” “treatment-related” and “economic/financial-related” along with 14 secondary criteria. The most frequently included secondary criteria were treatment efficacy （13 occurrences）， disease severity （9 occurrences）， safety （7 occurrences）， unmet medical need （6 occurrences）， and treatment cost （5 occurrences）. Rankings of relative importance identified treatment efficacy as the most valued criterion across most studies， followed by health insurance financing. CONCLUSIONS DCE applications in the value assessment of OMP have begun to converge on a relatively consistent core attribute framework and selection preference. Future research should further promote the use of DCE to inform attribute and criterion selection in multi-criteria decision analysis frameworks for OMP.

ObjectiveTo enhance teaching in postoperative cancer rehabilitation, this study developed an integrative Chinese-Western medicine postoperative oncology rehabilitation system, termed the medical oncology generative pre-trained transformer (MedOncoGPT). By introducing MedOncoGPT as an intelligent assistant, an integrated teaching model combining Chinese and Western medicine was established. The study evaluated its impact on students’ integrative clinical reasoning and practical abilities, providing support for instructional reform in related courses. MethodsUsing teaching resources as the knowledge base, MedOncoGPT was built upon the open-source ChatGLM model and incorporated Low-Rank Adaptation (LoRA) fine-tuning and retrieval-augmented generation (RAG) techniques to address postoperative integrative oncology scenarios. The system was applied in courses and clinical clerkships related to integrative oncology. In alignment with course objectives, a five-stage instructional process—pre-class preparation, in-class inquiry, simulated multidisciplinary consultation, clinical reinforcement, and teaching reflection—was designed to guide students in completing syndrome differentiation, comprehensive assessment, and follow-up planning within real or simulated case contexts. Comparative analyses of student engagement, syndrome differentiation thinking, evidence-based awareness, and interdisciplinary integration skills before and after the teaching reform were conducted using questionnaires, course assessments, classroom observations, and semi-structured interviews. ResultsFollowing the implementation of MedOncoGPT, students demonstrated improved performance in case analysis, prescription formulation, and integrative Chinese-Western medical evaluation compared with those receiving traditional instruction. Classroom participation and the relevance of student inquiries also increased. Self-assessment results indicated high levels of satisfaction with respect to clarity of integrative clinical reasoning, ability to retrieve and apply guideline-based evidence, and awareness of appropriate use of intelligent tools in clinical decision-making. More than 92% of students reported that the system facilitated understanding of abstract theoretical concepts presented in textbooks. Instructors noted that the system helped reduce lesson preparation time, enriched typical case materials and discussion scenarios, and promoted the translation of research findings into classroom teaching. Pilot data showed that, with MedOncoGPT assistance, the mean time for initial syndrome differentiation decreased from 18.4 min to 12.1 min, and the agreement rate increased from 68.3% to 82.5%. In the teaching pilot, the experimental group achieved a higher mean score on the final case analysis assessment than the control group (82.6 vs. 74.3). ConclusionThe integration of MedOncoGPT into teaching on postoperative integrative cancer rehabilitation enabled the establishment of a stable instructional process within existing curricula and enhanced students’ integrative clinical reasoning and evidence-based practice capabilities. The approach demonstrates positive potential for advancing the integration of research, clinical practice, and education and represents a valuable exploratory strategy for instructional reform in courses on integrative Chinese-Western medicine.

ObjectiveTo enhance teaching in postoperative cancer rehabilitation, this study developed an integrative Chinese-Western medicine postoperative oncology rehabilitation system, termed the medical oncology generative pre-trained transformer (MedOncoGPT). By introducing MedOncoGPT as an intelligent assistant, an integrated teaching model combining Chinese and Western medicine was established. The study evaluated its impact on students’ integrative clinical reasoning and practical abilities, providing support for instructional reform in related courses. MethodsUsing teaching resources as the knowledge base, MedOncoGPT was built upon the open-source ChatGLM model and incorporated Low-Rank Adaptation (LoRA) fine-tuning and retrieval-augmented generation (RAG) techniques to address postoperative integrative oncology scenarios. The system was applied in courses and clinical clerkships related to integrative oncology. In alignment with course objectives, a five-stage instructional process—pre-class preparation, in-class inquiry, simulated multidisciplinary consultation, clinical reinforcement, and teaching reflection—was designed to guide students in completing syndrome differentiation, comprehensive assessment, and follow-up planning within real or simulated case contexts. Comparative analyses of student engagement, syndrome differentiation thinking, evidence-based awareness, and interdisciplinary integration skills before and after the teaching reform were conducted using questionnaires, course assessments, classroom observations, and semi-structured interviews. ResultsFollowing the implementation of MedOncoGPT, students demonstrated improved performance in case analysis, prescription formulation, and integrative Chinese-Western medical evaluation compared with those receiving traditional instruction. Classroom participation and the relevance of student inquiries also increased. Self-assessment results indicated high levels of satisfaction with respect to clarity of integrative clinical reasoning, ability to retrieve and apply guideline-based evidence, and awareness of appropriate use of intelligent tools in clinical decision-making. More than 92% of students reported that the system facilitated understanding of abstract theoretical concepts presented in textbooks. Instructors noted that the system helped reduce lesson preparation time, enriched typical case materials and discussion scenarios, and promoted the translation of research findings into classroom teaching. Pilot data showed that, with MedOncoGPT assistance, the mean time for initial syndrome differentiation decreased from 18.4 min to 12.1 min, and the agreement rate increased from 68.3% to 82.5%. In the teaching pilot, the experimental group achieved a higher mean score on the final case analysis assessment than the control group (82.6 vs. 74.3). ConclusionThe integration of MedOncoGPT into teaching on postoperative integrative cancer rehabilitation enabled the establishment of a stable instructional process within existing curricula and enhanced students’ integrative clinical reasoning and evidence-based practice capabilities. The approach demonstrates positive potential for advancing the integration of research, clinical practice, and education and represents a valuable exploratory strategy for instructional reform in courses on integrative Chinese-Western medicine.

OBJECTIVES: To investigate the role and mechanism of copper overload-mediated endoplasmic reticulum stress (ERS) in vascular endothelial injury in Kawasaki disease (KD). METHODS: Four-week-old male C57BL/6 mice were randomly divided into four groups: control, KD, KD plus copper chelator tetrathiomolybdate (TTM), and KD plus ERS inhibitor AMG PERK 44 (AMG) (n=20 per group). A KD mouse model was established using Candida albicans extract. Human umbilical vein endothelial cells (HUVECs) were divided into control (intervention with healthy children's serum), KD (intervention with KD patients' serum), and KD+TTM (intervention with KD patients' serum plus 20 µmol/L TTM). Copper deposition in mouse heart tissue was assessed using rubeanic acid staining. Vascular pathological changes were observed using hematoxylin-eosin staining and measurement of abdominal aortic diameter and area. ERS activation was detected by transmission electron microscopy and immunofluorescence. HUVEC viability, apoptosis, and functional changes were evaluated using CCK8, flow cytometry, cell scratch assay, and angiogenesis experiments. ERS marker protein expression levels were measured by Western blot. RESULTS: Compared to the KD group, the KD+TTM and KD+AMG groups showed reduced copper deposition in the vascular wall, decreased swelling of coronary endothelial cells and endoplasmic reticulum, reduced inflammatory cell infiltration, and less abdominal aortic lesion expansion. The abdominal aortic diameter and area, and the fluorescence intensity of ERS marker proteins (GRP78 and CHOP) were significantly lower (P<0.05). Compared to the KD group, the KD+TTM group exhibited increased cell viability, tube number, and scratch healing rate, along with decreased apoptosis rate and expression of ERS marker proteins (GRP78, CHOP, ATF6, and p-PERK) (P<0.05). CONCLUSIONS Copper overload aggravates vascular endothelial injury in KD by activating the ERS pathway. TTM can exert protective effects on the endothelium by regulating copper metabolism and inhibiting the ERS pathway.
Endoplasmic Reticulum Stress ; Copper/toxicity* ; Male ; Mucocutaneous Lymph Node Syndrome/metabolism* ; Animals ; Humans ; Endoplasmic Reticulum Chaperone BiP ; Mice, Inbred C57BL ; Mice ; Human Umbilical Vein Endothelial Cells ; Apoptosis ; Endothelium, Vascular/injuries*

OBJECTIVE: To investigate the effects of Bushen Huoxue Granule on the ubiquitin-proteasome system (UPS) in an in vitro model of Parkinson's disease. METHODS: After treated with 1-methyl-4-phenylpyridinium (MPP⁺, 1 mmol/L) for 24 h, the cells were incubated with drug-free serum, Madopar-containing serum or Bushen Huoxue Granule-containing serum (BCS, 5%, 10%, and 20%) for another 24 h. The levels of α-synuclein (α-syn), tyrosine hydroxylase (TH) and UPS-related proteins were detected by Western blot. The expression levels of α-syn in PC12 cells were also analyzed by Western blot after treated with proteasome inhibitor MG132 and WT-α-syn plasmid transfection, respectively, as well as the alterations induced by subsequent BCS intervention. Immunocytochemistry was performed to determine the changes in α-syn phosphorylation at serine 129 (pSer129-α-syn) expression. The 20S proteasome levels were measured by enzyme-linked immunosorbnent assay. RESULTS: BCS (volume fraction ⩽20%) intervention could alleviate the MMP⁺-induced cell viability decrease (P<0.05). In the MPP⁺ treated cells, α-syn was up-regulated, while TH and proteins of UPS such as ubiquitin (Ub), Ub binding with Ub-activating enzyme (UBE1), Parkin and Ub C-terminal hydrolase-1 (UCHL-1) were down-regulated (P<0.05). BCS intervention could attenuate the above changes (P<0.05). The activity of BCS on blocking α-syn accumulation was weakened by MG132 (P<0.05). While α-syn level was significantly increased in cells transfected with plasmid, and reduced by BCS intervention (P<0.05). pSer129-α-syn was increased in MPP⁺-induced PC12 cells, whereas decreased by later BCS intervention (P<0.05). The 20S proteasome activity of MPP⁺-induced PC12 cells was decreased, but increased after BCS intervention (P<0.05). CONCLUSION BCS intervention protected UPS function, increased 20S proteasome activity, promoted pathological α-syn clearance, restored cell viability, and reversed the damage caused by MPP⁺ in the in vitro model of Parkinson's disease.
PC12 Cells ; alpha-Synuclein/metabolism* ; Rats ; Animals ; 1-Methyl-4-phenylpyridinium/toxicity* ; Proteasome Endopeptidase Complex/metabolism* ; Drugs, Chinese Herbal/pharmacology* ; Ubiquitin/metabolism* ; Cell Survival/drug effects* ; Phosphorylation/drug effects* ; Tyrosine 3-Monooxygenase/metabolism*

ObjectiveTo investigate the effect of the multidisciplinary team （MDT） management model in improving the prognosis of patients with cirrhotic portal hypertension. MethodsA total of 86 patients with cirrhotic portal hypertension who were admitted to Shenzhen Third People’s Hospital from May 2022 to July 2024 were enrolled， and according to whether the MDT treatment regimen was implemented， they were divided into execution group with 51 patients and non-execution group with 35 patients. Baseline clinical data were collected， and the patients were observed in terms of gastrointestinal bleeding， hepatic encephalopathy， liver cancer， and death from admission to the end of follow-up （January 2025）. The independent-samples t test was used for comparison of normally distributed continuous data between two groups， and the Wilcoxon rank-sum test was used for comparison of non-normally distributed continuous data between two groups； the chi-square test or the Fisher’s exact test was used for comparison of categorical data between groups. The Kaplan-Meier method was used to plot survival curves for the cumulative incidence rates of endpoint events （gastrointestinal bleeding， hepatic encephalopathy， liver cancer， and death）， and the Log-rank test was used for comparison between groups. The Cox proportional-hazards regression model analysis was used to investigate the effect of MDT management on the prognosis of patients. ResultsThere were significant differences between the execution group and the non-execution group in diameter of the portal vein （t=1.216， P=0.017） and ascites （χ²=4.515， P=0.034） at baseline. The patients were followed up for 14.6±6.2 months， and the survival curve analysis showed that there was a significant difference in the cumulative incidence rate of gastrointestinal bleeding between the two groups （χ²=4.573， P=0.024）， while there were no significant differences in the incidence rates of other outcome events between the two groups （all P>0.05）. The Cox regression analysis showed that the execution group had a reduced risk of gastrointestinal bleeding （hazard ratio=0.262， 95% confidence interval： 0.110 — 0.630， P=0.003）. ConclusionImplementation of the MDT treatment regimen can significantly reduce the short-term risk of gastrointestinal bleeding in patients with cirrhotic portal hypertension， while its long-term benefits require further follow-up verification.

An efficient analytical method was developed for simultaneous detection of alkylamines and alkylamides in food packaging plastics using liquid chromatography-high resolution mass spectrometry(LC-HRMS).Based on the physicochemical properties of alkylamines and alkylamides,as well as the complexity of plastic samples,sample pretreatment and chromatographic-mass spectrometric parameters were optimized.The samples were extracted by vortex-ultrasonic extraction with a methanol-acetonitrile mixture for 15 min,followed by nitrogen evaporation to concentrate the extract,reconstitution,and analysis.The chromatographic mobile phase consisted of 0.1%formic acid aqueous solution and acetonitrile,and a gradient elution was used.The electrospray ionization(ESI)source was operated in positive ion mode,and mass spectrometry data were collected in full scan and data-dependent acquisition modes.Quantification was performed using an isotope-labeled internal standard method.The results showed that within the quantification range of 1-1000 ng/mL,the calibration curves exhibited good linearity(R2>0.99).Some compounds interfered with the validation experiments at higher concentrations,so only 10 kinds of target analytes were validated.Using a mixed food packaging plastic matrix,the recoveries at spiking levels of 40,400,and 4000 ng/g were mostly between 66.0%and 117.1%,with relative standard deviations ranging from 0.6%to 10.6%.The method was applied to detect 14 food packaging plastic samples,and the results showed that the concentrations of alkylamines and alkylamides ranged from not detected to 8924 ng/g.This method offered high sensitivity and accuracy,and was suitable for the screening and quantitative determination of alkylamines and alkylamides in plastics.

ObjectiveTo investigate the association between neutrophil-to-lymphocyte and platelet ratio （NLPR） and recompensation in patients with hepatitis B cirrhotic ascites， and to establish an individualized risk prediction model. MethodsThe patients with hepatitis B cirrhotic ascites who were hospitalized in Department of Gastroenterology， The General Hospital of Western Theater Command of Chinese PLA， from January 2015 to December 2022 were enrolled. General information and laboratory markers were collected， and NLPR was calculated. The independent-samples t test or the Mann-Whitney U test was used for comparison of continuous data between two groups， and the chi-square test or the chi-square test with correction was used for comparison of categorical data between two groups. The subjects were randomly divided into a training set and a validation set at a ratio of 7∶3. In the training set， univariate and multivariate binary Logistic regression analyses were used to investigate the independent influencing factors for recompensation in patients with hepatitis B cirrhotic ascites， and a nomogram was established； the receiver operating characteristic （ROC） curve was used to assess the value of the new model in predicting recompensation in patients with hepatitis B cirrhotic ascites， and the Delong test was used for comparison of the area under the ROC curve （AUC）. The calibration curve and the decision curve were plotted for the model， and the model was assessed in terms of degree of fitting and predictive benefits. ResultsA total of 360 patients were enrolled， among whom134 achieved recompensation. There were 252 patients in the training set and 108 patients in the validation set， and there were no significant differences in baseline characteristics between the two groups （all P>0.05）. The Logistic regression analysis showed that the onset of hepatic encephalopathy （odds ratio ［OR］=0.066， 95% confidence interval ［CI］： 0.008 — 0.545， P=0.012）， NLPR （OR=0.950， 95%CI： 0.912 — 0.989， P=0.012）， alpha-fetoprotein （OR=1.012， 95%CI： 1.005 — 1.020， P<0.001）， and albumin （OR=1.096， 95%CI： 1.031 — 1.166， P=0.003） were independent influencing factors for recompensation in patients with hepatitis B cirrhotic ascites. The above four factors were included in a nomogram predictive model， which had an AUC of 0.776， a sensitivity of 66.5%， and a specificity of 76.3% in the training set and an AUC of 0.746， a sensitivity of 63.4%， and a specificity of 75.7% in the validation set， while Model for End-Stage Liver Disease score， Child-Pugh score， and albumin-bilirubin score had an AUC of 0.574， 0.628， and 0.621， respectively. The nomogram model had a better performance than the other three scores in predicting recompensation in patients with hepatitis B cirrhotic ascites （Z=4.191， 3.369， and 3.527， P<0.001， P=0.001， and P<0.001）. The calibration curve and the decision curve showed that the model had a good degree of fitting， and the decision made using this model could bring net benefits. ConclusionNLPR has a good value in predicting recompensation in patients with hepatitis B cirrhotic ascites， and the nomogram model established can help to predict recompensation in such patients in clinical practice.

This study established a droplet digital PCR(ddPCR)EvaGreen assay and probe methods for Schistosoma japonicum detection,and evaluated their application in detecting early infections in the S.japonicum host oncomelania and mice.Primers and corresponding probes for both ddPCR methods were designed and synthesized,and plasmids containing target sequences were constructed.The sensitivity of the two methods was tested through detection of the corresponding plasmids,and infectious and mixed oncomelania genomic DNA.Their specificity was evaluated by the detection of genomic DNA of negative oncomelania,Schistosoma mansoni,Clonorchis sinensis,Spirometra mansoni,and S.japonicum(as a positive control).The ddPCR probe method was evaluated by detection of early infection of oncomelania exposed tomiracidium with various ratios and incubation times,and the early migration and distribution of cercaria or schistosomula in mouse hosts infected with 200 cercaria via abdominal skin contact.According to standard curves constructed through the detection of plasmid serial dilutions,the regression equation for the EvaGreen assay was y=-0.839 9x+7.050 9,with a correlation coefficient R2=0.988 1,and the regression equation for the probe method was y=-1.047 5x+7.255 1,with a correlation coefficient R2=0.999 8.The lowest limit of plasmid detection with the probe method was between 38.94 cp/μL and 194.74 cp/μL.Both methods successfully detected positive reactions in the genomic DNA samples of infectious oncomelania at concentrations above 0.002 ng/μL and in the genomic DNA of each group of oncomelania mixtures.No significant differences between probe methods were observed in the detection values in the control group and the genomic DNA of negative oncomelania,S.mansoni,C.sinensis,and S.mansoni.However,the detection value of genomic DNA of negative oncomelania(291 ng/μL)with the EvaGreen assay was(20.3±4.39)cp/μL,a value significantly higher than the(1.5±0.1)cp/μL observed in the control group.For detection of early infection in oncomelania,the probe method detected Schistosoma japonicum DNA after 30 s incubation at room temperature with a≥5∶1 ratio of miracidium to oncomelania;the detection value peaked after a short time(5 min),and the peak value showed a fold increase similar to the increase in the miracidium to oncomelania ratio.Detection of early stage infection in mice with the probe method revealed that the schistosomula entered the lungs on day 2 and the liver on day 4,and continually migrated within the organs with abundant blood supply(spleen,kidney,and brain)in the first 9 days;moreover,a tendency toward ectopic parasitism was observed in the heart and pancreas on day 9,and a constantly negative control level was observed in the testes.The ddPCR probe method was more accurate and specific than the EvaGreen assay in the detection of plasmids,and infectious and mixed oncomelania,and the latter showed non-specific reactions in negative oncomelania detection.In a practical application,the probe method was demonstrated to be sensitive,to effectively reflect the early infection of oncomelania,and to reveal schistosomula migration and distribution in multiple organs of infected mice.

Objective:To construct a predictive model for mortality in patients with multiple trauma combined with thoracic injuries and evaluate its predictive value.Methods:A retrospective cohort study was conducted to analyze the clinical data of 184 patients with multiple trauma combined with thoracic injuries admitted to the International Zhuang Medicine Hospital Affiliated to Guangxi University of Chinese Medicine from April 2019 to December 2023, including 129 males and 55 females, aged 19-85 years [(46.1±13.7)years]. According to the prognostic outcomes at 3-month follow-up after discharge, the patients were divided into survival group ( n=145) and death group ( n=39). Data were recorded in both groups at admission, including gender, age, and cause of injury, laboratory tests such as systolic blood pressure, oxygen saturation (SaO 2), hemoglobin (Hb), neutrophil-to-lymphocyte ratio (NLR), and lactate, combined injuries such as the number of combined injuries, number of rib fracture, bilateral rib fracture, first-rib fracture, sternum fracture, thoracic vertebral fracture, bilateral pulmonary contusion, bilateral pneumothorax, subarachnoid hemorrhage, subdural hematoma, epidural hematoma, skull fracture, skull base fracture, cervical vertebral fracture, brain herniation, cerebral contusion, lumbar vertebral fracture, pelvic and abdominal cavity hematoma, liver injury, kidney injury, spleen injury, clavicle fracture, scapular fracture, femoral fracture, and pelvic fracture, and injury scores such as shock index (SI), modified shock index (MSI), injury severity score (ISS), revised trauma score (RTS), Glasgow coma score (GCS), and thoracic trauma severity (TTS) score. Univariate binary logistic regression analysis was used to screen for risk factors of death in patients with multiple trauma combined with thoracic injuries. LASSO regression and multivariate logistic regression analysis were employed to identify predictive variables and independent risk factors for mortality in those patients and to construct a regression equation. A nomogram prediction model based on the regression equation was developed using R language. Receiver operating characteristic (ROC) curves were plotted to evaluate the discrimination of the model. The ROC curves were internally validated using the Bootstrap method with 1 000 resamples. The calibration of the model was assessed using the Hosmer-Lemeshow (H-L) goodness-of-fit test. The clinical application value of the model was evaluated using decision curve analysis (DCA) and clinical impact curve (CIC) analysis. Results:There were statistically significant differences between the survival group and the death group in systolic blood pressure, SaO 2, NLR, lactate, number of combined injuries, subarachnoid hemorrhage, subdural hematoma, skull fracture, skull base fracture, brain herniation, liver injury, SI, MSI, ISS, RTS, GCS, and TTS ( P<0.05 or 0.01). The results of the univariate binary logistic regression analysis showed that the above-mentioned related variables except for systolic blood pressure were all significantly associated with death in patients with multiple trauma combined with thoracic injuries ( P<0.05 or 0.01). Five predictive variables, TTS, GCS, brain herniation, ISS, and lactate were obtained in LASSO regression analysis. The results of the multivariate logistic regression analysis showed that GCS ( OR=0.70, 95% CI 0.58, 0.83), brain herniation ( OR=46.18, 95% CI 4.27, 499.26), TTS ( OR=1.71, 95% CI 1.30, 2.24), and lactate ( OR=1.35, 95% CI 1.01, 1.80) were independent risk factors for death in patients with multiple trauma combined with thoracic injuries ( P<0.05 or 0.01). Based on the aforementioned independent risk factors, a regression formula was constructed as follows: P=e x/(1+e x), with the x=-0.36×"GCS"+3.83×"brain herniation"+0.53×"TTS"+0.30×"lactate levels"-11.03. The area under the ROC curve (AUC) of the predictive model for mortality in patients with multiple trauma combined with thoracic injuries based on the equation was 0.97 (95% CI 0.93, 1.00). The AUC was internally validated using the Bootstrap method with 1 000 samples, resulting in an AUC of 0.97 (95% CI 0.91, 1.00). The results of the H-L goodness-of-fit test showed that the bias-corrected calibration curve of the model was in good consistence with the actual curve and both of them were close to the ideal curve. In the evaluation of the clinical application value of the predictive model, the DCA results showed that the predictive model could achieve good clinical net benefit. The CIC results showed that when the threshold probability was greater than 0.7, the model-identified high-risk patients for death highly matched the patients who actually died. Conclusion:The predictive model for mortality in patients with multiple trauma combined with thoracic injuries based on GCS, brain herniation, TTS, and lactate has good predictive performance and clinical application value.