AIM:To analyze the performance value of high risk factors in population-based colorectal cancer(CRC) screening in China.METHODS:We compared the performance value of the immunochemical fecal occult blood test(iFOBT) an...AIM:To analyze the performance value of high risk factors in population-based colorectal cancer(CRC) screening in China.METHODS:We compared the performance value of the immunochemical fecal occult blood test(iFOBT) and other high risk factors questionnaire in a population sample of 13 214 community residents who completed both the iFOBT and questionnaire investigation.Patients with either a positive iFOBT and/or questionnaire were regarded as a high risk population and those eligible were asked to undergo colonoscopy.RESULTS:The iFOBT had the highest positive predictive value and negative predictive value in screening for advanced neoplasia.The iFOBT had the highest sensitivity,lowest number of extra false positive results associated with the detection of one extra abnormality for screening advanced neoplasias and adenomas.A history of chronic cholecystitis or cholecystectomy,chronic appendicitis or appendectomy,and chronic diarrhea also had a higher sensitivity than a history of adenomatous polyps in screening for advanced neoplasias and adenomas.The sensitivity of a history of chronic cholecystitis or cholecystectomy was highest among the 10 high risk factors in screening for nonadenomatous polyps.A history of chronic appendicitis or appendectomy,chronic constipation,chronic diarrhea,mucous and bloody stool,CRC in first degree relatives,malignant tumor and a positive iFOBT also had higher sensitivities than a history of adenomas polyps in screening for non-adenomatous polyps.Except for a history of malignant tumor in screening for non-adenomatous polyps,the gain in sensitivity was associated with an increase in extra false positive results associated with the detection of one extra abnormality.CONCLUSION:The iFOBT may be the best marker for screening for advanced neoplasias and adenomas.Some unique high risk factors may play an important role in CRC screening in China.展开更多
An antibody phage library was screened with two target molecules, IFNα-2a and FGFR-GST, and the KD value of each round of panning was measured. It was found that the apparent KD values decreased along with each addit...An antibody phage library was screened with two target molecules, IFNα-2a and FGFR-GST, and the KD value of each round of panning was measured. It was found that the apparent KD values decreased along with each additional panning round, which indicates the increase of the binding affinity between the phage and the target molecules. This result shows that the KD value is a reliable intrinsic parameter and a new method for screening efficiency detection is thus provided.展开更多
BACKGROUND The 5-year survival rate of patients with advanced gastric cancer remains extremely low(<15%),whereas the 5-year survival rate of patients with early gastric cancer(EGC)is>90%.Consequently,strengtheni...BACKGROUND The 5-year survival rate of patients with advanced gastric cancer remains extremely low(<15%),whereas the 5-year survival rate of patients with early gastric cancer(EGC)is>90%.Consequently,strengthening the screening of patients with EGC and precancerous lesions(PCLs)is essential.AIM To identify the value of serum pepsinogen ratio(PGR)screening for EGC and PCLs in the Shengli Oilfield Central Hospital.METHODS We first selected 385 patients with gastric lesions in the Youcheng area,deter-mining benign lesions,PCLs,and EGC in 135,123,and 127 cases,respec-tively,based on endoscopy and case diagnosis.The positive rates of pepsinogen I,pep-sinogen II and Helicobacter pylori(H.pylori)in the three groups were detected,and the PGR was calculated.Subsequently,we plotted receiver operating charac-teristic curves to analyze the screening value of PGR and H.pylori-positive rates for PCLs and EGC.RESULTS PGR expression demonstrated a decreasing trend in patients with benign lesions,PCLs,and EGC successively according to the detection results,whereas the H.pylori-positive rate was notably increased in patients with PCLs and EGC compared to those with benign lesions.The area under the curves(AUCs)of PGR,H.pylori,and their combination in differentiating patients with benign lesions from those with PCLs were 0.611,0.582,and 0.689,respectively;PGR,H.pylori,and their combination had an AUC of 0.618,0.502,and 0.618 in distinguishing PCL patients from EGC patients,respectively;the AUCs of PGR,H.pylori,and their combination in discriminating patients with benign lesions from those with EGC were 0.708,0.581,and 0.750,respectively.CONCLUSION PGR has great screening potential for patients with EGC and PCLs in the Youcheng area,and the screening efficiency is further improved by combining the H.pylori-positive rate.展开更多
Objective:To study the screening for cervical cancer in postmenopausal women in liquid-based cell test(TCT)application value.Methods:From January 2023 to March 2024 hospital check-ups and outpatient reached 400 cases ...Objective:To study the screening for cervical cancer in postmenopausal women in liquid-based cell test(TCT)application value.Methods:From January 2023 to March 2024 hospital check-ups and outpatient reached 400 cases of postmenopausal women,and they were TCT and HPV detection,during the study period to pathological diagnosis of numerical results as the standard,analysis of TCT detection application of screening for cervical cancer in postmenopausal women and the effect.Results:After the TCT detection,the inflammation group and normal group by use of HPV testing positive rate higher than other groups(P<0.05).Hospital after pathological diagnosis and research,after the screening system found CINⅠlevel and above cases about 39 cases,the TCT and HPV detection rate of positive difference is not obvious,and there is no statistical significance(P>0.05).Joint test analysis,the sensitivity and specificity were higher than that of TCT and HPV testing positive(P<0.05).Conclusion:TCT detection screening for cervical cancer in postmenopausal women is of great importance to the application,if you can join HPV testing,help to improve the detection sensitivity,avoid missed diagnosis of problems,and then for treatment and later restore to lay a solid foundation.展开更多
The aim of this study was to evaluate the effects of low-dose tibolone therapy on ovarian area, uterine volume and endometrial thickness, and define the cut-off value of endometrial thickness for curettage during uter...The aim of this study was to evaluate the effects of low-dose tibolone therapy on ovarian area, uterine volume and endometrial thickness, and define the cut-off value of endometrial thickness for curettage during uterine bleeding. We followed 619 postmenopausal women, aged 40-60 years, for two years. There were 301 subjects in the low-dose tibolone treatment group and 318 subjects in the control group. The ovarian area, uterine volume and endometrial thickness in all participants were measured by transvaginal ultrasound prior to, one and two years post enrollment, respectively. Endometrial specimens were collected from all subjects with abnormal uterine bleeding during the follow-up period. We found that the uterine volume in the treatment group was greater than that in the control group, and the difference was significant （P〈0.05）, but there were no significant differences in ovarian area and endometrial thickness between the two groups （P〉0.05）. When the cut-off value for endometrial thickness was 7.35 ram, the sensitivity and specificity were 100% and 79.07%, respectively, and 85.71% and 93.02% when 7.55 mm was set as the cut-offduring tibolone therapy. The results indicate that low-dose tibolone therapy may postpone uterine atrophy and the cut-off value of endometrial thickness may be appropriately adjusted for curettage.展开更多
The transverse relaxation time (T_(2)) cut-off value plays a crucial role in nuclear magnetic resonance for identifying movable and immovable boundaries, evaluating permeability, and determining fluid saturation in pe...The transverse relaxation time (T_(2)) cut-off value plays a crucial role in nuclear magnetic resonance for identifying movable and immovable boundaries, evaluating permeability, and determining fluid saturation in petrophysical characterization of petroleum reservoirs. This study focuses on the systematic analysis of T_(2) spectra and T_(2) cut-off values in low-permeability reservoir rocks. Analysis of 36 low-permeability cores revealed a wide distribution of T_(2) cut-off values, ranging from 7 to 50 ms. Additionally, the T_(2) spectra exhibited multimodal characteristics, predominantly displaying unimodal and bimodal morphologies, with a few trimodal morphologies, which are inherently influenced by different pore types. Fractal characteristics of pore structure in fully water-saturated cores were captured through the T_(2) spectra, which were calculated using generalized fractal and multifractal theories. To augment the limited dataset of 36 cores, the synthetic minority oversampling technique was employed. Models for evaluating the T_(2) cut-off value were separately developed based on the classified T_(2) spectra, considering the number of peaks, and utilizing generalized fractal dimensions at the weight <0 and the singular intensity range. The underlying mechanism is that the singular intensity and generalized fractal dimensions at the weight <0 can detect the T_(2) spectral shift. However, the T_(2) spectral shift has negligible effects on multifractal spectrum function difference and generalized fractal dimensions at the weight >0. The primary objective of this work is to gain insights into the relationship between the kurtosis of the T_(2) spectrum and pore types, as well as to predict the T_(2) cut-off value of low-permeability rocks using machine learning and data augmentation techniques.展开更多
Background:Salt stress significantly inhibits the growth,development,and productivity of cotton because of osmotic,ionic,and oxidative stresses.Therefore,the screening and development of salt tolerant cotton cultivars...Background:Salt stress significantly inhibits the growth,development,and productivity of cotton because of osmotic,ionic,and oxidative stresses.Therefore,the screening and development of salt tolerant cotton cultivars is a key issue towards sustainable agriculture.This study subjected 11 upland cotton genotypes at the seedling growth stage to five different salt concentrations and evaluated their salt tolerance and reliable traits.Results:Several morpho-physiological traits were measured after 10 days of salinity treatment and the salt tolerance performance varied significantly among the tested cotton genotypes.The optimal Na Cl concentration for the evaluation of salt tolerance was 200 mmol·L-1.Membership function value and salt tolerance index were used to identify the most consistent salt tolerance traits.Leaf relative water content and photosynthesis were identified as reliable indicators for salt tolerance at the seedling stage.All considered traits related to salt tolerance indices were significantly and positively correlated with each other except for malondialdehyde.Cluster heat map analysis based on the morpho-physiological salt tolerance-indices clearly discriminated the 11 cotton genotypes into three different salt tolerance clusters.Cluster I represented the salt-tolerant genotypes(Z9807,Z0228,and Z7526)whereas clusters II(Z0710,Z7514,Z1910,and Z7516)and III(Z0102,Z7780,Z9648,and Z9612)represented moderately salttolerant and salt-sensitive genotypes,respectively.Conclusions:A hydroponic screening system was established.Leaf relative water content and photosynthesis were identified as two reliable traits that adequately represented the salt tolerance of cotton genotypes at the seedling growth stage.Furthermore,three salt-tolerant genotypes were identified,which might be used as genetic resources for the salt-tolerance breeding of cotton.展开更多
Iron deficiency anemia is one of the most prevalent nutritional deficiency worldwide. The commonly used cut-off values for identifying iron deficiency are extrapolated from older children and may not be suitable for i...Iron deficiency anemia is one of the most prevalent nutritional deficiency worldwide. The commonly used cut-off values for identifying iron deficiency are extrapolated from older children and may not be suitable for infants. Therefore, our study aimed to establish appropriate cut-off values for the evaluation of iron status in Chinese infants. Pregnant women who delivered at 〉37 gestational weeks with normal iron status were recruited. Later, infants with normal birth weight and who were breastfed in the first 4 months were selected. Blood samples were collected to assess hemoglobin, serum ferritin, soluble transferrin receptor, mean corpuscular volume and free erythrocyte protoporphyrin. Cut-offs of all iron indices were determined as the limit of 95% confidence interval.展开更多
BACKGROUND Elevated plasma homocysteine(Hcy)levels are associated with increased risk of colorectal cancer(CRC),particularly in patients with systemic inflammation or AIM To evaluate serum Hcy levels as a predictive m...BACKGROUND Elevated plasma homocysteine(Hcy)levels are associated with increased risk of colorectal cancer(CRC),particularly in patients with systemic inflammation or AIM To evaluate serum Hcy levels as a predictive marker of lesion risk and CRC to prioritize patients undergoing diagnostic colonoscopy.METHODS We conducted a prospective cohort study of 301 fecal occult blood test-positive patients at San Agustín University Hospital in Asturias,Spain.Plasma Hcy levels were measured prior to the colonoscopy and classified into three thresholds:≤12,12-15,and>15μmol/L.Colonoscopy and histopathology determined the presence of low-risk,high-risk polyps or adenocarcinoma.Predictive performance of serum Hcy to detect lesions was assessed using logistic regression and diagnostic accuracy measures,including models adjusted for age and sex.RESULTS Median Hcy levels rose progressively with lesion severity,reaching 15.3μmol/L in adenocarcinoma(P<0.001).Higher levels were also observed in men and individuals aged 65 or older.A threshold above 15μmol/L showed good sensitivity(76.6%)and positive predictive value(87.2%)for detecting adenocarcinoma.When combined with age and sex,predictive accuracy improved(area under the receiver operating characteristic curve=0.706).Based on these findings,we propose a three-tier triage system:Green(≤12μmol/L in both sexes,colonoscopy within three months),Yellow(>12-15μmol/L in men,intervention within one month and red(≥15 in either sex or>12μmol/L in women,immediate colonoscopy).CONCLUSION Serum Hcy is a clinically useful biomarker for identifying high-risk colorectal lesions and cancer,particularly when interpreted in combination with age and sex.This composite model improves predictive accuracy and enables a structured three-tiered triage system that supports faster colonoscopy scheduling for at-risk groups.The traffic light approach offers a low cost,scalable strategy to reduce delays and optimize resource use in CRC screening,especially in public health systems with limited endoscopic capacity.展开更多
The aim of the present study was to investigate minimum inhibitory concentration(MIC)distributions by broth microdilution(BMD)method and to determine the preliminary epidemiological cut-off value(ECV)of colistin by ep...The aim of the present study was to investigate minimum inhibitory concentration(MIC)distributions by broth microdilution(BMD)method and to determine the preliminary epidemiological cut-off value(ECV)of colistin by epidemiological cut-off(ECOFF)finder against E.coli from chickens in China.Anal swabs were collected from chicken farms in China.BMD method was used to measure MIC50 and MIC90 of colistin which were 2 and 4μg•mL^(-1),respectively.MIC frequency distributions for colistin were used to estimate preliminary ECV(8μg•mL^(-1)).High percentages of resistance to ampicillin(94.12%),nalidixic acid(94.12%),enrofloxacin(94.12%),tetracycline(94.12%),ciprofloxacin(88.24%),florfenicol(88.24%),neomycin(64.71%),gentamicin(58.82%),levofloxacin(58.82%),doxycycline(88.24%)and cefalexin(76.47%)were found.In addition,low percentages of resistance to amikacin(5.88%),spectinomycin(17.65%)and fosfomycin(41.18%)were noted.Notably,amoxicillin,sulfisoxazole and trimethoprim resulted in a 100%resistance generation efficacy rate.Prevalence of mcr-1 in E.coli(9/17)in chromosomal DNA was higher than mcr-4(2/17)gene,and mcr-1(5/17)was higher than mcr-4(3/17)in plasmid.展开更多
BACKGROUND Glycated hemoglobin A1c(HbA1c)is considered the most suitable for diabetes mellitus diagnosis due to its accuracy and convenience.However,the effect of HbA1c on diabetic retinopathy(DR)in the Han and Korean...BACKGROUND Glycated hemoglobin A1c(HbA1c)is considered the most suitable for diabetes mellitus diagnosis due to its accuracy and convenience.However,the effect of HbA1c on diabetic retinopathy(DR)in the Han and Korean populations in Jilin,China,remains inconclusive.AIM To determine the best cut-off of HbA1c for diagnosing DR among the Chinese.METHODS This cross-sectional study included 1933 participants from the Yanbian area of Jilin Province,China.Trained investigators employed a questionnaire-based survey,physical examination,laboratory tests,and fundus photography for the investigation.The best cut-off value for HbA1c was established via the receiver operating characteristic curve.The factors associated with HbA1c-associated risk factors were determined via linear regression.RESULTS The analysis included 887 eligible Chinese Han and Korean participants,591 of whom were assigned randomly to the training set and 296 to the validation set.The prevalence of DR was 3.27% in the total population.HbA1c of 6.2% was the best cut-off value in the training set,while it was 5.9% in the validation set.In both Chinese Han and Korean populations,an HbA1c level of 6.2% was the best cut-off value.The optimal cut-off values of fasting blood glucose(FBG)≥7 mmol/L and<7 mmol/L were 8.1% and 6.2% respectively in Han populations,while those in Korean populations were 6.9%and 5.3%,respectively.Age,body mass index,and FBG were determined as the risk factors impacting HbA1c levels.CONCLUSION HbA1c may serve as a useful diagnostic indicator for DR.An HbA1c level of 6.2% may be an appropriate cut-off value for DR detection in the Chinese population.展开更多
Several prediction models have been developed to estimate the outcomes of prostate biopsies. Most of these tools were designed for use with Western populations and have not been validated across different ethnic group...Several prediction models have been developed to estimate the outcomes of prostate biopsies. Most of these tools were designed for use with Western populations and have not been validated across different ethnic groups. Therefore, we evaluated the predictive value of the Prostate Cancer Prevention Trial （PCPT） and the European Randomized Study of Screening for Prostate Cancer （ERSPC） risk calculators in a Chinese cohort. Clinicopathological information was obtained from 495 Chinese men who had undergone extended prostate biopsies between January 2009 and March 2011. The estimated probabilities of prostate cancer and high-grade disease （Gleason 〉6） were calculated using the PCPT and ERSPC risk calculators. Overall measures, discrimination, calibration and clinical usefulness were assessed for the model evaluation. Of these patients, 28.7% were diagnosed with prostate cancer and 19.4% had high-grade disease. Compared to the PCPT model and the prostate-specific antigen （PSA） threshold of 4 ng m1-1, the ERSPC risk calculator exhibited better discriminative ability for predicting positive biopsies and high-grade disease （the area under the curve was 0.831 and 0.852, respectively, P〈O.01 for both）. Decision curve analysis also suggested the favourable clinical utility of the ERSPC calculator in the validation dataset. Both prediction models demonstrated miscalibration： the risk of prostate cancer and high-grade disease was overestimated by approximately 20% for a wide range of predicted probabilities. In conclusion, the ERSPC risk calculator outperformed both the PCPT model and the PSA threshold of 4 ng ml- z in predicting prostate cancer and high-grade disease in Chinese patients. However, the prediction tools derived from Western men significantly overestimated the probability of prostate cancer and high-grade disease compared to the outcomes of biopsies in a Chinese cohort.展开更多
AIM:To present a content-based image retrieval(CBIR) system that supports the classification of breast tissue density and can be used in the processing chain to adapt parameters for lesion segmentation and classificat...AIM:To present a content-based image retrieval(CBIR) system that supports the classification of breast tissue density and can be used in the processing chain to adapt parameters for lesion segmentation and classification.METHODS:Breast density is characterized by image texture using singular value decomposition(SVD) and histograms.Pattern similarity is computed by a support vector machine(SVM) to separate the four BI-RADS tissue categories.The crucial number of remaining singular values is varied(SVD),and linear,radial,and polynomial kernels are investigated(SVM).The system is supported by a large reference database for training and evaluation.Experiments are based on 5-fold cross validation.RESULTS:Adopted from DDSM,MIAS,LLNL,and RWTH datasets,the reference database is composed of over 10000 various mammograms with unified and reliable ground truth.An average precision of 82.14% is obtained using 25 singular values(SVD),polynomial kernel and the one-against-one(SVM).CONCLUSION:Breast density characterization using SVD allied with SVM for image retrieval enable the development of a CBIR system that can effectively aid radiologists in their diagnosis.展开更多
Objective: The aim of this retrospective study was to evaluate diagnostic accuracy of serum thyroglobulin antibody (TgAb) in thyroglobulin (Tg)-negative and TgAb-positive (Tg<sup>-</sup>TgAb<sup>+<...Objective: The aim of this retrospective study was to evaluate diagnostic accuracy of serum thyroglobulin antibody (TgAb) in thyroglobulin (Tg)-negative and TgAb-positive (Tg<sup>-</sup>TgAb<sup>+</sup>) patients with differentiated thyroid carcinoma (DTC). Method: We studied 341 patients with histologically confirmed DTC who had undergone remnant ablation and showed Tg<sup>-</sup>TgAb<sup>+</sup> assessed by electrochemiluminescence immunoassay (ECLIA). The cases were divided into two groups, including recurrence group 119 cases and no evidence of disease (NED) group 222 cases. Receiver operating characteristic (ROC) curve analysis was carried out. The symmetric measures of the two diagnostic methods (the golden standard and the diagnostic standard as serum TgAb level alone) were analyzed using McNemar test and measure of agreement Kappa. Results: Serum TgAb level (1381.292 ± 1017.221) IU/ml of patients with recurrent group was significantly higher than that (125.559 ± 314.047) IU/ml of NED group (P = 0.000 0.001). The area under the ROC curve was 0.962 and its asymptotic 95% confidence interval (CI) was (0.942, 0.982) that was high statistical significance. The cut-off value of TgAb was determined and interpreted at 246.695 IU/ml with sensitivity (92.40%) and specificity (92.30%). McNemar test showed that the diagnostic results of the two methods were not significant difference (P = 0.230 > 0.05). Measure of agreement Kappa was 0.841, P = 0.000 0.001 that showed the agreement of the two diagnostic methods was significant. Conclusion: Serum TgAb is a useful tumor marker for recurrence in Tg-negative and TgAb-positive DTC patients who underwent thyroidectomy and remnant ablation. The cut-off value of TgAb is 246.695 IU/ml, that is to say, serum TgAb level upon 246.695 IU/ml may be associated with the persistence or recurrence of DTC.展开更多
Objective To compare the value and consistency among the Patient Generated-Subjective Global Assessment(PG-SGA)and the Prognostic Nutrition Index(PNI)for assessing nutritional status in gastrointestinal tumor patients...Objective To compare the value and consistency among the Patient Generated-Subjective Global Assessment(PG-SGA)and the Prognostic Nutrition Index(PNI)for assessing nutritional status in gastrointestinal tumor patients.Methods 251 patients from gastric cancer surgical ward from January 2019 to January 2020 were recruited through convenience sampling in this respective study.Nutritional screening and assessment were conducted for 251 gastrointestinal tumor patients using the nutritional risk screening 2002(NRS 2002)PG-SGA,and the PNI.PNI was calculated using the serum albumin level and the total lymphocyte count obtained from the patients’routine laboratory examination when they were admitted to the hospital.The receiver operating characteristic(ROC)of the PG SGA and the PNI were plotted with the NRS 2002 used as the gold standard,and the diagnostic value of the PG-SGA and PNI was reflected by the area under the curve(AUC),sensitivity,specificity and Youden index.We then determined the optimal cut-off for the PNI and tested the consistency of the PG-SGA and PNI.Results The optimal cut-off point for the PNI was calculated to be 50.78.The AUC of the PG-SGA was 0.908(95%CI 0.871-0.944).The sensitivity was 89.9%,specificity was 76.2%and the Youden index was 0.661.The AUC of the PNI was 0.594(95%CI 0.516-0.572).The sensitivity was 73.8%,specificity was 44.3%and the Youden index was 0.181.In the consistency test,the kappa value was 0.838(P<0.001).Conclusion The PNI is of limited value for assessing malnutrition,although it did have good consistency with the PG-SGA.The combination of the PNI and PG-SGA can be used for diagnosing assessing malnutrition in clinical practice.展开更多
The rare earth elements and high-field-strength elements(REE-HFSE)exploration sector conducts most evaluations at deposit and smaller scales.It is not evident how the sector performs a preceding exploration stage—rat...The rare earth elements and high-field-strength elements(REE-HFSE)exploration sector conducts most evaluations at deposit and smaller scales.It is not evident how the sector performs a preceding exploration stage—rating and prioritising REE-HFSE mineralised provinces—to determine which provinces are prospective enough to warrant investment.Here we present an objective,repeatable,low-cost method to screen any REE-HFSE province,as a foundation for district-scale investigations or asset evaluations.It is original for REE-HFSE screening,and adapted from regional scale copper,cobalt and petroleum exploration,and CO2 storage,screening methods.It is centred upon a mineralised province’s favourability for potential value creation,and to identify:(a)its main information gaps;(b)its weakest links;(c)its exploration maturity and remaining potential category;(d)how it compares against other REE-HFSE provinces;and(e)if further investigation is justified.This method incorporates geoscience,strategy,economic and socio-environmental factors in a way that is understandable and directly usable across stakeholder groups.The workflow is systematic,yet flexible enough to accommodate organisationspecific criteria,and usable for other commodities.It provides the platform to build a global REE-HFSE province map and database consistently across national boundaries and organisations.Categories for the extent of province exploration maturity and remaining mineral potential are proposed.We illustrate the applicability of these methods using the Gardar REE-HFSE Province(GRHP)of south Greenland.We conclude that it is a moderate size,frontier province that is currently of questionable favourability for value creation.To move GRHP into a positive favourability class,its current weak links need strengthening by research,government policy and industry stakeholders:evaluate the mineral system;integrate all information geospatially and place it in the public domain;help the region improve some community health and safety issues;convert some mineral resources into an Ore Reserves category;commence mining and sales production.展开更多
BACKGROUND Down syndrome(DS)is one of the most common chromosomal aneuploidy diseases.Prenatal screening and diagnostic tests can aid the early diagnosis,appropriate management of these fetuses,and give parents an inf...BACKGROUND Down syndrome(DS)is one of the most common chromosomal aneuploidy diseases.Prenatal screening and diagnostic tests can aid the early diagnosis,appropriate management of these fetuses,and give parents an informed choice about whether or not to terminate a pregnancy.In recent years,investigations have been conducted to achieve a high detection rate(DR)and reduce the false positive rate(FPR).Hospitals have accumulated large numbers of screened cases.However,artificial intelligence methods are rarely used in the risk assessment of prenatal screening for DS.AIM To use a support vector machine algorithm,classification and regression tree algorithm,and AdaBoost algorithm in machine learning for modeling and analysis of prenatal DS screening.METHODS The dataset was from the Center for Prenatal Diagnosis at the First Hospital of Jilin University.We designed and developed intelligent algorithms based on the synthetic minority over-sampling technique(SMOTE)-Tomek and adaptive synthetic sampling over-sampling techniques to preprocess the dataset of prenatal screening information.The machine learning model was then established.Finally,the feasibility of artificial intelligence algorithms in DS screening evaluation is discussed.RESULTS The database contained 31 DS diagnosed cases,accounting for 0.03%of all patients.The dataset showed a large difference between the numbers of DS affected and non-affected cases.A combination of over-sampling and undersampling techniques can greatly increase the performance of the algorithm at processing non-balanced datasets.As the number of iterations increases,the combination of the classification and regression tree algorithm and the SMOTETomek over-sampling technique can obtain a high DR while keeping the FPR to a minimum.CONCLUSION The support vector machine algorithm and the classification and regression tree algorithm achieved good results on the DS screening dataset.When the T21 risk cutoff value was set to 270,machine learning methods had a higher DR and a lower FPR than statistical methods.展开更多
Screening variables with significant features as the input data of network, is an important step in application of neural network to predict and analysis problems. This paper proposed a method using MIV algorithm to s...Screening variables with significant features as the input data of network, is an important step in application of neural network to predict and analysis problems. This paper proposed a method using MIV algorithm to screen variables of BP neural network.And experimental results show that, the proposed technique is practical and reliable.展开更多
Objective: to analyze the application value of mean erythrocyte volume in the screening of thalassemia in pregnant women. Methods: from January 2020 to March 2021, 123 pregnant women who received prenatal examination ...Objective: to analyze the application value of mean erythrocyte volume in the screening of thalassemia in pregnant women. Methods: from January 2020 to March 2021, 123 pregnant women who received prenatal examination in our hospital and were diagnosed with thalassemia by genetic examination were selected as the research objects, and they were taken as the observation group, and 100 pregnant women who received pregnancy examination during the same period but the results were normal were taken as the control group. The results of routine blood tests of the two were retrospectively analyzed. The sensitivity, specificity and total accuracy of average erythrocyte volume in the diagnosis of different types of thalassemia were calculated. Results: among 123 pregnant women with thalassemia confirmed by gene testing, 65 cases were α thalassemia, 50 cases were β thalassemia and 8 cases were α and β combined thalassemia. MCV test values of pregnant women in the two groups were compared, indicating that pregnant women with different types of thalassemia were significantly lower than normal pregnant women, with statistical difference (P < 0.05). The sensitivity and specificity of α thalassemia, β thalassemia, α and β compound thalassemia were 90.77%, 92.00% and 100.00%, respectively, using genetic test results as the diagnostic gold standard. The overall accuracy was 78.03%. Conclusion: mean erythrocyte volume is of great value in the screening of thalassemia in pregnant women.展开更多
基金Supported by 11th 5-Year Key Programs for Science and Technology Development of China,No.2006BAI02A08
文摘AIM:To analyze the performance value of high risk factors in population-based colorectal cancer(CRC) screening in China.METHODS:We compared the performance value of the immunochemical fecal occult blood test(iFOBT) and other high risk factors questionnaire in a population sample of 13 214 community residents who completed both the iFOBT and questionnaire investigation.Patients with either a positive iFOBT and/or questionnaire were regarded as a high risk population and those eligible were asked to undergo colonoscopy.RESULTS:The iFOBT had the highest positive predictive value and negative predictive value in screening for advanced neoplasia.The iFOBT had the highest sensitivity,lowest number of extra false positive results associated with the detection of one extra abnormality for screening advanced neoplasias and adenomas.A history of chronic cholecystitis or cholecystectomy,chronic appendicitis or appendectomy,and chronic diarrhea also had a higher sensitivity than a history of adenomatous polyps in screening for advanced neoplasias and adenomas.The sensitivity of a history of chronic cholecystitis or cholecystectomy was highest among the 10 high risk factors in screening for nonadenomatous polyps.A history of chronic appendicitis or appendectomy,chronic constipation,chronic diarrhea,mucous and bloody stool,CRC in first degree relatives,malignant tumor and a positive iFOBT also had higher sensitivities than a history of adenomas polyps in screening for non-adenomatous polyps.Except for a history of malignant tumor in screening for non-adenomatous polyps,the gain in sensitivity was associated with an increase in extra false positive results associated with the detection of one extra abnormality.CONCLUSION:The iFOBT may be the best marker for screening for advanced neoplasias and adenomas.Some unique high risk factors may play an important role in CRC screening in China.
文摘An antibody phage library was screened with two target molecules, IFNα-2a and FGFR-GST, and the KD value of each round of panning was measured. It was found that the apparent KD values decreased along with each additional panning round, which indicates the increase of the binding affinity between the phage and the target molecules. This result shows that the KD value is a reliable intrinsic parameter and a new method for screening efficiency detection is thus provided.
文摘BACKGROUND The 5-year survival rate of patients with advanced gastric cancer remains extremely low(<15%),whereas the 5-year survival rate of patients with early gastric cancer(EGC)is>90%.Consequently,strengthening the screening of patients with EGC and precancerous lesions(PCLs)is essential.AIM To identify the value of serum pepsinogen ratio(PGR)screening for EGC and PCLs in the Shengli Oilfield Central Hospital.METHODS We first selected 385 patients with gastric lesions in the Youcheng area,deter-mining benign lesions,PCLs,and EGC in 135,123,and 127 cases,respec-tively,based on endoscopy and case diagnosis.The positive rates of pepsinogen I,pep-sinogen II and Helicobacter pylori(H.pylori)in the three groups were detected,and the PGR was calculated.Subsequently,we plotted receiver operating charac-teristic curves to analyze the screening value of PGR and H.pylori-positive rates for PCLs and EGC.RESULTS PGR expression demonstrated a decreasing trend in patients with benign lesions,PCLs,and EGC successively according to the detection results,whereas the H.pylori-positive rate was notably increased in patients with PCLs and EGC compared to those with benign lesions.The area under the curves(AUCs)of PGR,H.pylori,and their combination in differentiating patients with benign lesions from those with PCLs were 0.611,0.582,and 0.689,respectively;PGR,H.pylori,and their combination had an AUC of 0.618,0.502,and 0.618 in distinguishing PCL patients from EGC patients,respectively;the AUCs of PGR,H.pylori,and their combination in discriminating patients with benign lesions from those with EGC were 0.708,0.581,and 0.750,respectively.CONCLUSION PGR has great screening potential for patients with EGC and PCLs in the Youcheng area,and the screening efficiency is further improved by combining the H.pylori-positive rate.
文摘Objective:To study the screening for cervical cancer in postmenopausal women in liquid-based cell test(TCT)application value.Methods:From January 2023 to March 2024 hospital check-ups and outpatient reached 400 cases of postmenopausal women,and they were TCT and HPV detection,during the study period to pathological diagnosis of numerical results as the standard,analysis of TCT detection application of screening for cervical cancer in postmenopausal women and the effect.Results:After the TCT detection,the inflammation group and normal group by use of HPV testing positive rate higher than other groups(P<0.05).Hospital after pathological diagnosis and research,after the screening system found CINⅠlevel and above cases about 39 cases,the TCT and HPV detection rate of positive difference is not obvious,and there is no statistical significance(P>0.05).Joint test analysis,the sensitivity and specificity were higher than that of TCT and HPV testing positive(P<0.05).Conclusion:TCT detection screening for cervical cancer in postmenopausal women is of great importance to the application,if you can join HPV testing,help to improve the detection sensitivity,avoid missed diagnosis of problems,and then for treatment and later restore to lay a solid foundation.
基金supported by the Sci-tech Research Development Program of Shaanxi Province (No.2015SF015)
文摘The aim of this study was to evaluate the effects of low-dose tibolone therapy on ovarian area, uterine volume and endometrial thickness, and define the cut-off value of endometrial thickness for curettage during uterine bleeding. We followed 619 postmenopausal women, aged 40-60 years, for two years. There were 301 subjects in the low-dose tibolone treatment group and 318 subjects in the control group. The ovarian area, uterine volume and endometrial thickness in all participants were measured by transvaginal ultrasound prior to, one and two years post enrollment, respectively. Endometrial specimens were collected from all subjects with abnormal uterine bleeding during the follow-up period. We found that the uterine volume in the treatment group was greater than that in the control group, and the difference was significant （P〈0.05）, but there were no significant differences in ovarian area and endometrial thickness between the two groups （P〉0.05）. When the cut-off value for endometrial thickness was 7.35 ram, the sensitivity and specificity were 100% and 79.07%, respectively, and 85.71% and 93.02% when 7.55 mm was set as the cut-offduring tibolone therapy. The results indicate that low-dose tibolone therapy may postpone uterine atrophy and the cut-off value of endometrial thickness may be appropriately adjusted for curettage.
基金supported by National Natural Science Foundation of China(Nos.42002171,42172159)China Postdoctoral Science Foundation(Nos.2020TQ0299,2020M682520)Postdoctoral Innovation Science Foundation of Hubei Province of China.
文摘The transverse relaxation time (T_(2)) cut-off value plays a crucial role in nuclear magnetic resonance for identifying movable and immovable boundaries, evaluating permeability, and determining fluid saturation in petrophysical characterization of petroleum reservoirs. This study focuses on the systematic analysis of T_(2) spectra and T_(2) cut-off values in low-permeability reservoir rocks. Analysis of 36 low-permeability cores revealed a wide distribution of T_(2) cut-off values, ranging from 7 to 50 ms. Additionally, the T_(2) spectra exhibited multimodal characteristics, predominantly displaying unimodal and bimodal morphologies, with a few trimodal morphologies, which are inherently influenced by different pore types. Fractal characteristics of pore structure in fully water-saturated cores were captured through the T_(2) spectra, which were calculated using generalized fractal and multifractal theories. To augment the limited dataset of 36 cores, the synthetic minority oversampling technique was employed. Models for evaluating the T_(2) cut-off value were separately developed based on the classified T_(2) spectra, considering the number of peaks, and utilizing generalized fractal dimensions at the weight <0 and the singular intensity range. The underlying mechanism is that the singular intensity and generalized fractal dimensions at the weight <0 can detect the T_(2) spectral shift. However, the T_(2) spectral shift has negligible effects on multifractal spectrum function difference and generalized fractal dimensions at the weight >0. The primary objective of this work is to gain insights into the relationship between the kurtosis of the T_(2) spectrum and pore types, as well as to predict the T_(2) cut-off value of low-permeability rocks using machine learning and data augmentation techniques.
基金supported by National Key R&D Program(2017YFD0101600)State Key Laboratory of Cotton Biology(CB2019C17)。
文摘Background:Salt stress significantly inhibits the growth,development,and productivity of cotton because of osmotic,ionic,and oxidative stresses.Therefore,the screening and development of salt tolerant cotton cultivars is a key issue towards sustainable agriculture.This study subjected 11 upland cotton genotypes at the seedling growth stage to five different salt concentrations and evaluated their salt tolerance and reliable traits.Results:Several morpho-physiological traits were measured after 10 days of salinity treatment and the salt tolerance performance varied significantly among the tested cotton genotypes.The optimal Na Cl concentration for the evaluation of salt tolerance was 200 mmol·L-1.Membership function value and salt tolerance index were used to identify the most consistent salt tolerance traits.Leaf relative water content and photosynthesis were identified as reliable indicators for salt tolerance at the seedling stage.All considered traits related to salt tolerance indices were significantly and positively correlated with each other except for malondialdehyde.Cluster heat map analysis based on the morpho-physiological salt tolerance-indices clearly discriminated the 11 cotton genotypes into three different salt tolerance clusters.Cluster I represented the salt-tolerant genotypes(Z9807,Z0228,and Z7526)whereas clusters II(Z0710,Z7514,Z1910,and Z7516)and III(Z0102,Z7780,Z9648,and Z9612)represented moderately salttolerant and salt-sensitive genotypes,respectively.Conclusions:A hydroponic screening system was established.Leaf relative water content and photosynthesis were identified as two reliable traits that adequately represented the salt tolerance of cotton genotypes at the seedling growth stage.Furthermore,three salt-tolerant genotypes were identified,which might be used as genetic resources for the salt-tolerance breeding of cotton.
基金supported by Natural Science Foundation of China(Grant No.30972483)The Chinese clinical trial registry number is ChiCTR-TRC-12002838
文摘Iron deficiency anemia is one of the most prevalent nutritional deficiency worldwide. The commonly used cut-off values for identifying iron deficiency are extrapolated from older children and may not be suitable for infants. Therefore, our study aimed to establish appropriate cut-off values for the evaluation of iron status in Chinese infants. Pregnant women who delivered at 〉37 gestational weeks with normal iron status were recruited. Later, infants with normal birth weight and who were breastfed in the first 4 months were selected. Blood samples were collected to assess hemoglobin, serum ferritin, soluble transferrin receptor, mean corpuscular volume and free erythrocyte protoporphyrin. Cut-offs of all iron indices were determined as the limit of 95% confidence interval.
文摘BACKGROUND Elevated plasma homocysteine(Hcy)levels are associated with increased risk of colorectal cancer(CRC),particularly in patients with systemic inflammation or AIM To evaluate serum Hcy levels as a predictive marker of lesion risk and CRC to prioritize patients undergoing diagnostic colonoscopy.METHODS We conducted a prospective cohort study of 301 fecal occult blood test-positive patients at San Agustín University Hospital in Asturias,Spain.Plasma Hcy levels were measured prior to the colonoscopy and classified into three thresholds:≤12,12-15,and>15μmol/L.Colonoscopy and histopathology determined the presence of low-risk,high-risk polyps or adenocarcinoma.Predictive performance of serum Hcy to detect lesions was assessed using logistic regression and diagnostic accuracy measures,including models adjusted for age and sex.RESULTS Median Hcy levels rose progressively with lesion severity,reaching 15.3μmol/L in adenocarcinoma(P<0.001).Higher levels were also observed in men and individuals aged 65 or older.A threshold above 15μmol/L showed good sensitivity(76.6%)and positive predictive value(87.2%)for detecting adenocarcinoma.When combined with age and sex,predictive accuracy improved(area under the receiver operating characteristic curve=0.706).Based on these findings,we propose a three-tier triage system:Green(≤12μmol/L in both sexes,colonoscopy within three months),Yellow(>12-15μmol/L in men,intervention within one month and red(≥15 in either sex or>12μmol/L in women,immediate colonoscopy).CONCLUSION Serum Hcy is a clinically useful biomarker for identifying high-risk colorectal lesions and cancer,particularly when interpreted in combination with age and sex.This composite model improves predictive accuracy and enables a structured three-tiered triage system that supports faster colonoscopy scheduling for at-risk groups.The traffic light approach offers a low cost,scalable strategy to reduce delays and optimize resource use in CRC screening,especially in public health systems with limited endoscopic capacity.
基金Supported by the National Key Research and Development Program of China(2016YFD0501302)the National Natural Science Foundation of China(31772801)。
文摘The aim of the present study was to investigate minimum inhibitory concentration(MIC)distributions by broth microdilution(BMD)method and to determine the preliminary epidemiological cut-off value(ECV)of colistin by epidemiological cut-off(ECOFF)finder against E.coli from chickens in China.Anal swabs were collected from chicken farms in China.BMD method was used to measure MIC50 and MIC90 of colistin which were 2 and 4μg•mL^(-1),respectively.MIC frequency distributions for colistin were used to estimate preliminary ECV(8μg•mL^(-1)).High percentages of resistance to ampicillin(94.12%),nalidixic acid(94.12%),enrofloxacin(94.12%),tetracycline(94.12%),ciprofloxacin(88.24%),florfenicol(88.24%),neomycin(64.71%),gentamicin(58.82%),levofloxacin(58.82%),doxycycline(88.24%)and cefalexin(76.47%)were found.In addition,low percentages of resistance to amikacin(5.88%),spectinomycin(17.65%)and fosfomycin(41.18%)were noted.Notably,amoxicillin,sulfisoxazole and trimethoprim resulted in a 100%resistance generation efficacy rate.Prevalence of mcr-1 in E.coli(9/17)in chromosomal DNA was higher than mcr-4(2/17)gene,and mcr-1(5/17)was higher than mcr-4(3/17)in plasmid.
基金Supported by National Key R&D Program of China,No.2016YFC1305700.
文摘BACKGROUND Glycated hemoglobin A1c(HbA1c)is considered the most suitable for diabetes mellitus diagnosis due to its accuracy and convenience.However,the effect of HbA1c on diabetic retinopathy(DR)in the Han and Korean populations in Jilin,China,remains inconclusive.AIM To determine the best cut-off of HbA1c for diagnosing DR among the Chinese.METHODS This cross-sectional study included 1933 participants from the Yanbian area of Jilin Province,China.Trained investigators employed a questionnaire-based survey,physical examination,laboratory tests,and fundus photography for the investigation.The best cut-off value for HbA1c was established via the receiver operating characteristic curve.The factors associated with HbA1c-associated risk factors were determined via linear regression.RESULTS The analysis included 887 eligible Chinese Han and Korean participants,591 of whom were assigned randomly to the training set and 296 to the validation set.The prevalence of DR was 3.27% in the total population.HbA1c of 6.2% was the best cut-off value in the training set,while it was 5.9% in the validation set.In both Chinese Han and Korean populations,an HbA1c level of 6.2% was the best cut-off value.The optimal cut-off values of fasting blood glucose(FBG)≥7 mmol/L and<7 mmol/L were 8.1% and 6.2% respectively in Han populations,while those in Korean populations were 6.9%and 5.3%,respectively.Age,body mass index,and FBG were determined as the risk factors impacting HbA1c levels.CONCLUSION HbA1c may serve as a useful diagnostic indicator for DR.An HbA1c level of 6.2% may be an appropriate cut-off value for DR detection in the Chinese population.
文摘Several prediction models have been developed to estimate the outcomes of prostate biopsies. Most of these tools were designed for use with Western populations and have not been validated across different ethnic groups. Therefore, we evaluated the predictive value of the Prostate Cancer Prevention Trial （PCPT） and the European Randomized Study of Screening for Prostate Cancer （ERSPC） risk calculators in a Chinese cohort. Clinicopathological information was obtained from 495 Chinese men who had undergone extended prostate biopsies between January 2009 and March 2011. The estimated probabilities of prostate cancer and high-grade disease （Gleason 〉6） were calculated using the PCPT and ERSPC risk calculators. Overall measures, discrimination, calibration and clinical usefulness were assessed for the model evaluation. Of these patients, 28.7% were diagnosed with prostate cancer and 19.4% had high-grade disease. Compared to the PCPT model and the prostate-specific antigen （PSA） threshold of 4 ng m1-1, the ERSPC risk calculator exhibited better discriminative ability for predicting positive biopsies and high-grade disease （the area under the curve was 0.831 and 0.852, respectively, P〈O.01 for both）. Decision curve analysis also suggested the favourable clinical utility of the ERSPC calculator in the validation dataset. Both prediction models demonstrated miscalibration： the risk of prostate cancer and high-grade disease was overestimated by approximately 20% for a wide range of predicted probabilities. In conclusion, the ERSPC risk calculator outperformed both the PCPT model and the PSA threshold of 4 ng ml- z in predicting prostate cancer and high-grade disease in Chinese patients. However, the prediction tools derived from Western men significantly overestimated the probability of prostate cancer and high-grade disease compared to the outcomes of biopsies in a Chinese cohort.
基金Supported by CNPq-Brazil,Grants 306193/2007-8,471518/ 2007-7,307373/2006-1 and 484893/2007-6,by FAPEMIG,Grant PPM 347/08,and by CAPESThe IRMA project is funded by the German Research Foundation(DFG),Le 1108/4 and Le 1108/9
文摘AIM:To present a content-based image retrieval(CBIR) system that supports the classification of breast tissue density and can be used in the processing chain to adapt parameters for lesion segmentation and classification.METHODS:Breast density is characterized by image texture using singular value decomposition(SVD) and histograms.Pattern similarity is computed by a support vector machine(SVM) to separate the four BI-RADS tissue categories.The crucial number of remaining singular values is varied(SVD),and linear,radial,and polynomial kernels are investigated(SVM).The system is supported by a large reference database for training and evaluation.Experiments are based on 5-fold cross validation.RESULTS:Adopted from DDSM,MIAS,LLNL,and RWTH datasets,the reference database is composed of over 10000 various mammograms with unified and reliable ground truth.An average precision of 82.14% is obtained using 25 singular values(SVD),polynomial kernel and the one-against-one(SVM).CONCLUSION:Breast density characterization using SVD allied with SVM for image retrieval enable the development of a CBIR system that can effectively aid radiologists in their diagnosis.
文摘Objective: The aim of this retrospective study was to evaluate diagnostic accuracy of serum thyroglobulin antibody (TgAb) in thyroglobulin (Tg)-negative and TgAb-positive (Tg<sup>-</sup>TgAb<sup>+</sup>) patients with differentiated thyroid carcinoma (DTC). Method: We studied 341 patients with histologically confirmed DTC who had undergone remnant ablation and showed Tg<sup>-</sup>TgAb<sup>+</sup> assessed by electrochemiluminescence immunoassay (ECLIA). The cases were divided into two groups, including recurrence group 119 cases and no evidence of disease (NED) group 222 cases. Receiver operating characteristic (ROC) curve analysis was carried out. The symmetric measures of the two diagnostic methods (the golden standard and the diagnostic standard as serum TgAb level alone) were analyzed using McNemar test and measure of agreement Kappa. Results: Serum TgAb level (1381.292 ± 1017.221) IU/ml of patients with recurrent group was significantly higher than that (125.559 ± 314.047) IU/ml of NED group (P = 0.000 0.001). The area under the ROC curve was 0.962 and its asymptotic 95% confidence interval (CI) was (0.942, 0.982) that was high statistical significance. The cut-off value of TgAb was determined and interpreted at 246.695 IU/ml with sensitivity (92.40%) and specificity (92.30%). McNemar test showed that the diagnostic results of the two methods were not significant difference (P = 0.230 > 0.05). Measure of agreement Kappa was 0.841, P = 0.000 0.001 that showed the agreement of the two diagnostic methods was significant. Conclusion: Serum TgAb is a useful tumor marker for recurrence in Tg-negative and TgAb-positive DTC patients who underwent thyroidectomy and remnant ablation. The cut-off value of TgAb is 246.695 IU/ml, that is to say, serum TgAb level upon 246.695 IU/ml may be associated with the persistence or recurrence of DTC.
文摘Objective To compare the value and consistency among the Patient Generated-Subjective Global Assessment(PG-SGA)and the Prognostic Nutrition Index(PNI)for assessing nutritional status in gastrointestinal tumor patients.Methods 251 patients from gastric cancer surgical ward from January 2019 to January 2020 were recruited through convenience sampling in this respective study.Nutritional screening and assessment were conducted for 251 gastrointestinal tumor patients using the nutritional risk screening 2002(NRS 2002)PG-SGA,and the PNI.PNI was calculated using the serum albumin level and the total lymphocyte count obtained from the patients’routine laboratory examination when they were admitted to the hospital.The receiver operating characteristic(ROC)of the PG SGA and the PNI were plotted with the NRS 2002 used as the gold standard,and the diagnostic value of the PG-SGA and PNI was reflected by the area under the curve(AUC),sensitivity,specificity and Youden index.We then determined the optimal cut-off for the PNI and tested the consistency of the PG-SGA and PNI.Results The optimal cut-off point for the PNI was calculated to be 50.78.The AUC of the PG-SGA was 0.908(95%CI 0.871-0.944).The sensitivity was 89.9%,specificity was 76.2%and the Youden index was 0.661.The AUC of the PNI was 0.594(95%CI 0.516-0.572).The sensitivity was 73.8%,specificity was 44.3%and the Youden index was 0.181.In the consistency test,the kappa value was 0.838(P<0.001).Conclusion The PNI is of limited value for assessing malnutrition,although it did have good consistency with the PG-SGA.The combination of the PNI and PG-SGA can be used for diagnosing assessing malnutrition in clinical practice.
基金This research,and the costs to prepare this document for open access publication,was part of the HiTech Alk Carb project,under the European Union Horizon 2020 research and innovation programme,grant agreement number[689909]。
文摘The rare earth elements and high-field-strength elements(REE-HFSE)exploration sector conducts most evaluations at deposit and smaller scales.It is not evident how the sector performs a preceding exploration stage—rating and prioritising REE-HFSE mineralised provinces—to determine which provinces are prospective enough to warrant investment.Here we present an objective,repeatable,low-cost method to screen any REE-HFSE province,as a foundation for district-scale investigations or asset evaluations.It is original for REE-HFSE screening,and adapted from regional scale copper,cobalt and petroleum exploration,and CO2 storage,screening methods.It is centred upon a mineralised province’s favourability for potential value creation,and to identify:(a)its main information gaps;(b)its weakest links;(c)its exploration maturity and remaining potential category;(d)how it compares against other REE-HFSE provinces;and(e)if further investigation is justified.This method incorporates geoscience,strategy,economic and socio-environmental factors in a way that is understandable and directly usable across stakeholder groups.The workflow is systematic,yet flexible enough to accommodate organisationspecific criteria,and usable for other commodities.It provides the platform to build a global REE-HFSE province map and database consistently across national boundaries and organisations.Categories for the extent of province exploration maturity and remaining mineral potential are proposed.We illustrate the applicability of these methods using the Gardar REE-HFSE Province(GRHP)of south Greenland.We conclude that it is a moderate size,frontier province that is currently of questionable favourability for value creation.To move GRHP into a positive favourability class,its current weak links need strengthening by research,government policy and industry stakeholders:evaluate the mineral system;integrate all information geospatially and place it in the public domain;help the region improve some community health and safety issues;convert some mineral resources into an Ore Reserves category;commence mining and sales production.
基金Supported by Science and Technology Department of Jilin Province,No.20190302073GX.
文摘BACKGROUND Down syndrome(DS)is one of the most common chromosomal aneuploidy diseases.Prenatal screening and diagnostic tests can aid the early diagnosis,appropriate management of these fetuses,and give parents an informed choice about whether or not to terminate a pregnancy.In recent years,investigations have been conducted to achieve a high detection rate(DR)and reduce the false positive rate(FPR).Hospitals have accumulated large numbers of screened cases.However,artificial intelligence methods are rarely used in the risk assessment of prenatal screening for DS.AIM To use a support vector machine algorithm,classification and regression tree algorithm,and AdaBoost algorithm in machine learning for modeling and analysis of prenatal DS screening.METHODS The dataset was from the Center for Prenatal Diagnosis at the First Hospital of Jilin University.We designed and developed intelligent algorithms based on the synthetic minority over-sampling technique(SMOTE)-Tomek and adaptive synthetic sampling over-sampling techniques to preprocess the dataset of prenatal screening information.The machine learning model was then established.Finally,the feasibility of artificial intelligence algorithms in DS screening evaluation is discussed.RESULTS The database contained 31 DS diagnosed cases,accounting for 0.03%of all patients.The dataset showed a large difference between the numbers of DS affected and non-affected cases.A combination of over-sampling and undersampling techniques can greatly increase the performance of the algorithm at processing non-balanced datasets.As the number of iterations increases,the combination of the classification and regression tree algorithm and the SMOTETomek over-sampling technique can obtain a high DR while keeping the FPR to a minimum.CONCLUSION The support vector machine algorithm and the classification and regression tree algorithm achieved good results on the DS screening dataset.When the T21 risk cutoff value was set to 270,machine learning methods had a higher DR and a lower FPR than statistical methods.
文摘Screening variables with significant features as the input data of network, is an important step in application of neural network to predict and analysis problems. This paper proposed a method using MIV algorithm to screen variables of BP neural network.And experimental results show that, the proposed technique is practical and reliable.
文摘Objective: to analyze the application value of mean erythrocyte volume in the screening of thalassemia in pregnant women. Methods: from January 2020 to March 2021, 123 pregnant women who received prenatal examination in our hospital and were diagnosed with thalassemia by genetic examination were selected as the research objects, and they were taken as the observation group, and 100 pregnant women who received pregnancy examination during the same period but the results were normal were taken as the control group. The results of routine blood tests of the two were retrospectively analyzed. The sensitivity, specificity and total accuracy of average erythrocyte volume in the diagnosis of different types of thalassemia were calculated. Results: among 123 pregnant women with thalassemia confirmed by gene testing, 65 cases were α thalassemia, 50 cases were β thalassemia and 8 cases were α and β combined thalassemia. MCV test values of pregnant women in the two groups were compared, indicating that pregnant women with different types of thalassemia were significantly lower than normal pregnant women, with statistical difference (P < 0.05). The sensitivity and specificity of α thalassemia, β thalassemia, α and β compound thalassemia were 90.77%, 92.00% and 100.00%, respectively, using genetic test results as the diagnostic gold standard. The overall accuracy was 78.03%. Conclusion: mean erythrocyte volume is of great value in the screening of thalassemia in pregnant women.
