Body composition and metabolic syndrome in patients with type 1 diabetes

BACKGROUND In recent years,the prevalence of obesity and metabolic syndrome in type 1 diabetes(T1DM)patients has gradually increased.Insulin resistance in T1DM deserves attention.It is necessary to clarify the relationship between body composition,metabolic syndrome and insulin resistance in T1DM to guide clinical treatment and intervention.AIM To assess body composition(BC)in T1DM patients and evaluate the relationship between BC,metabolic syndrome(MS),and insulin resistance in these indi-viduals.METHODS A total of 101 subjects with T1DM,aged 10 years or older,and with a disease duration of over 1 year were included.Bioelectrical impedance analysis using the Tsinghua-Tongfang BC Analyzer BCA-1B was employed to measure various BC parameters.Clinical and laboratory data were collected,and insulin resistance was calculated using the estimated glucose disposal rate(eGDR).RESULTS MS was diagnosed in 16/101 patients(15.84%),overweight in 16/101 patients(15.84%),obesity in 4/101(3.96%),hypertension in 34/101(33.66%%)and dyslip-idemia in 16/101 patients(15.84%).Visceral fat index(VFI)and trunk fat mass were significantly and negatively correlated with eGDR(both P<0.001).Female patients exhibited higher body fat percentage and visceral fat ratio compared to male patients.Binary logistic regression analysis revealed that significant factors for MS included eGDR[P=0.017,odds ratio(OR)=0.109],VFI(P=0.030,OR=3.529),and a family history of diabetes(P=0.004,OR=0.228).Significant factors for hypertension included eGDR(P<0.001,OR=0.488)and skeletal muscle mass(P=0.003,OR=1.111).Significant factors for dyslipidemia included trunk fat mass(P=0.033,OR=1.202)and eGDR(P=0.037,OR=0.708).CONCLUSION Visceral fat was found to be a superior predictor of MS compared to conventional measures such as body mass index and waist-to-hip ratio in Chinese individuals with T1DM.BC analysis,specifically identifying visceral fat(trunk fat),may play an important role in identifying the increased risk of MS in non-obese patients with T1DM.

Influence of ear tags on the results of body composition analysis in mice

Background:The aim of this study was to investigate the influence of marking meth-ods on the outcomes of body composition analysis and provide guidance for the se-lection of marking methods in mouse body composition analysis.Methods:Male C57BL/6J mice aged 6 weeks were randomly assigned for pre-and post-ear tagging measurements.The body composition of the mice was measured using a small animal body composition analyzer,which provided measurements of the mass of fat,lean,and free fluid.Then,the mass of fat,lean and free fluid to body weight ratio was gained.Further data analysis was conducted to obtain the range and coeffi-cient of variation in body composition measurements for each mouse.The distribution of fat and lean tissue in the mice was also analyzed by comparing the fat-to-lean ratio.Results:(1)The mass of all body composition components in the ear tagging group was significantly lower than that in the control group.(2)There was a significant in-crease in the range and coefficient of variation of body composition measurements between the ear tagging group and the control group.(3)The fat-to-lean ratio in the ear tagging group was significantly lower than that in the control group.Conclusions:Ear tagging significantly lowered the results of body composition analy-sis in mice and higher the results of measurement error.Therefore,ear tagging should be avoided as much as possible when conducting body composition analysis experi-ments in mice.

Automated body composition analysis system based on chest CT for evaluating content of muscle and adipose

Objective To establish a body composition analysis system based on chest CT,and to observe its value for evaluating content of chest muscle and adipose.Methods T7—T8 layer CT images of 108 pneumonia patients were collected(segmented dataset),and chest CT data of 984 patients were screened from the COVID 19-CT dataset(10 cases were randomly selected as whole test dataset,the remaining 974 cases were selected as layer selection dataset).T7—T8 layer was classified based on convolutional neural network(CNN)derived networks,including ResNet,ResNeXt,MobileNet,ShuffleNet,DenseNet,EfficientNet and ConvNeXt,then the accuracy,precision,recall and specificity were used to evaluate the performance of layer selection dataset.The skeletal muscle(SM),subcutaneous adipose tissue(SAT),intermuscular adipose tissue(IMAT)and visceral adipose tissue(VAT)were segmented using classical fully CNN(FCN)derived network,including FCN,SegNet,UNet,Attention UNet,UNET++,nnUNet,UNeXt and CMUNeXt,then Dice similarity coefficient(DSC),intersection over union(IoU)and 95 Hausdorff distance(HD)were used to evaluate the performance of segmented dataset.The automatic body composition analysis system was constructed based on optimal layer selection network and segmentation network,the mean absolute error(MAE),root mean squared error(RMSE)and standard deviation(SD)of MAE were used to evaluate the performance of automatic system for testing the whole test dataset.Results The accuracy,precision,recall and specificity of DenseNet network for automatically classifying T7—T8 layer from chest CT images was 95.06%,84.83%,92.27%and 95.78%,respectively,which were all higher than those of the other layer selection networks.In segmentation of SM,SAT,IMAT and overall,DSC and IoU of UNet++network were all higher,while 95HD of UNet++network were all lower than those of the other segmentation networks.Using DenseNet as the layer selection network and UNet++as the segmentation network,MAE of the automatic body composition analysis system for predicting SM,SAT,IMAT,VAT and MAE was 27.09,6.95,6.65 and 3.35 cm 2,respectively.Conclusion The body composition analysis system based on chest CT could be used to assess content of chest muscle and adipose.Among them,the UNet++network had better segmentation performance in adipose tissue than SM.

The Role of Body Composition Analyzer in the Preoperative Assessment of Breast Cancer Patients

Background: The segmental multi-frequency bioelectrical impedance analysis (SMF-BIA) is a useful method for evaluating physical health and nutritional status in various clinical settings. But less is known about its role in the preoperative assessment of breast cancer patients. Herein, we try to monitor the changes in body composition of preoperative patients by SMF-BIA and figure out its association with clinical features. Methods: The changes in body composition were monitored by SMF-BIA in 563 female patients with breast cancer. Monitor body moisture and collect relevant data on the day before surgery as a prospective study. Retrospective analysis will be conducted based on preoperative data and pathological results after lymph node resection, Spearman’s correlation coefficients were calculated to investigate the correlation among parameters. Results: We found that the body water, extracellular water ratio, and bioelectrical impedance of the affected upper limbs of patients with different tumor stages or different numbers of lymph node metastases were significantly different from those of their healthy upper limbs (P P P P P Conclusion: SMF-BIA can help monitor the changes in body composition of breast cancer patients and provide detailed information for making a personalized treatment plan and individual nursing schedule. However, the value of SMF-BIA in preoperative assessment still needs to be validated in large prospective clinical trials.

Body Composition in Sickle Cell Disease Patients in the Steady State

Introduction: Previous studies in sickle cell disease (SCD) patients have demonstrated low muscle mass (MM) and high fat mass (FM) percentages compared to individuals with normal hemoglobin. The relationship between the evolutions of body composition (BC) parameters in the active SCD population is not well elucidated. The aim of the present study was to assess the body composition in active adult SCD patients in sub-Saharan Africa during the inter-critical period. Methodology: We conducted a descriptive and analytical cross-sectional study over an 8-month period. Eighteen SCD patients (sex ratio = 1) reported regular physical activity (RPA) corresponding to level 3 (RPA of moderate intensity) of the 4-level Saltin-Grimby physical activity scale were recruited. Anthropometric and BC parameters such as BMI, percentage FM and percentage MM were evaluated using an impedance meter. Results: The study population had a mean age of 26 ± 7 years and a mean BMI of 20.5 ± 1.9 kg/m2. We found a significantly higher percentage of FM in women compared to the men (25.6% ± 10.2% vs 11.1% ± 2.1%;p = 0.001). For the proportion of MM, all the women had a normal percentage. The men mostly had high levels of MM compared with reference norms. Men had significantly greater MM percentages than women (45.4% ± 1.8% vs. 26.5% ± 1.4%;p Conclusion: RPA appears to have positive effects on BC in active population with SCD, and a greater-than-expected effect was observed on MM in male patients. Promoting regular, adapted physical activity would be a promising way of improving BC parameters and quality of life in the SCD population. Further studies with larger cohorts will be needed to better substantiate these results.

Failure characteristics and the damage evolution of a composite bearing structure in pillar-side cemented paste backfilling

A backfilling body-coal pillar-backfilling body(BPB)structure formed by pillar-side cemented paste backfilling can bear overburden stress and ensure safe mining.However,the failure response of BPB composite samples must be investigated.This paper examines the deformation characteristics and damage evolution of six types of BPB composite samples using a digital speckle correlation method under uniaxial compression conditions.A new damage evolution equation was established on the basis of the input strain energy and dissipated strain energy at the peak stress.The prevention and control mechanisms of the backfilling body on the coal pillar instability were discussed.The results show that the deformation localization and macroscopic cracks of the BPB composite samples first appeared at the coal-backfilling interface,and then expanded to the backfilling elements,ultimately appearing in the coal elements.The elastic strain energy in the BPB composite samples reached a maximum at the peak stress,whereas the dissipated energy continued to accumulate and increase.The damage evolution curve and equation agree well with the test results,providing further understanding of instability prevention and the control mechanisms of the BPB composite samples.The restraining effect on the coal pillar was gradually reduced with decreasing backfilling body element's volume ratio,and the BPB composite structure became more vulnerable to failure.This research is expected to guide the design,stability monitoring,instability prevention,and control of BPB structures in pillar-side cemented paste backfilling mining.

Association of Breastfeeding Duration with Body Composition in Children Aged 3–5 Years

Objective This study aimed to assess the relationship between the body composition of children aged 3–5 years and breastfeeding status and duration.Methods The study was conducted using data from the National Nutrition and Health Systematic Survey for children 0–17 years of age in China(CNHSC),a nationwide cross-sectional study.Breastfeeding information and potential confounders were collected using standardized questionnaires administered through face-to-face interviews.The body composition of preschool children was measured using bioelectrical impedance analysis.A multivariate linear regression model was used to assess the relationship between breastfeeding duration and body composition after adjusting for potential confounders.Results In total,2,008 participants were included in the study.Of these,89.2%were ever breastfed and the median duration of breastfeeding was 12 months(IQR 7–15 months).Among children aged 3 years,the height-for-age Z-score(HAZ)for the ever breastfed group was lower than that for never breastfed group(0.12 vs.0.42,P=0.043).In addition,the weight-for-age Z-score(WAZ)of the ever breastfed group was lower than that of the never breastfed group(0.31 vs.0.65,P=0.026),and the WAZ was lower in children aged 4 years who breastfed between 12 and 23 months than in those who never breastfed.Compared to the formula-fed children,the fat-free mass of breastfed infants was higher for children aged 3 years(12.84 kg vs.12.52 kg,P=0.015)and lower for those aged 4 years(14.31 kg vs.14.64 kg,P=0.048),but no difference was detected for children aged 5 years(16.40 kg vs.16.42 kg,P=0.910)after adjusting for potential confounders.No significant difference was detected in the weight-for-height Z-score(WHZ),body mass index(BMI)-for-age Z-score(BAZ),fat-free mass index,and body fat indicators in the ever breastfed and never breastfed groups and among various breastfeeding duration groups for children aged 3–5 years.Conclusion No obvious associations were detected between breastfeeding duration,BMI,and fat mass indicators.Future prospective studies should explore the relationship between breastfeeding status and fat-free mass.

Exploring overweight and obesity beyond body mass index:A body composition analysis in people with and without patellofemoral pain

Background:We compared body mass index(BMI),body fat,and skeletal muscle mass between(1) a mixed-sex nonathletic cohort of people with patellofemoral pain(PFP) and pain-free people,and(2) a nonathletic cohort of people with PFP and pain-free people subgrouped by sex(i.e.,men and women with PFP vs.pain-free men and women).Methods:This cross-sectional study included 114 people with PFP(71 women,43 men) and 54 pain-free controls(32 women,22 men).All participants attended a single testing session to assess body composition measures,which included BMI,percentage of body fat(%BFBioimpedance),and skeletal muscle mass(both assessed by bioelectrical impedance analysis),and percentage of body fat(%BFskinfoid)(assessed by skinfold caliper analysis).A one-way univariate analysis of covariance(age and physical activity levels as covariates) was used to compare body composition measures between groups(i.e.,PFP vs.pain-free group;women with PFP vs.pain-free women;men with PFP vs.pain-free men).Results:Women with PFP presented significantly higher BMI,%BFBiompedance,and %BFSkinfold,and lower skeletal muscle mass compared to pain-free women(p≤0.04;effect size:-0.47 to 0.85).Men with PFP and men and women combined had no differences in BMI,%BFBioimpedance,%BFSkinfold,and skeletal muscle mass compared to their respective pain-free groups(p> 0.05).Conclusion:Our findings indicate that BMI and body composition measures should be considered as part of the evaluation and management of people with PFP,especially in women,who have demonstrated higher BMI and body fat and lower skeletal muscle mass compared to pain-free controls.Future studies should not assess body composition measures in a mixed-sex population without distinguishing men participants from women participants.

Bridging the gap:Unveiling the crisis of physical inactivity in inflammatory bowel diseases

In this editorial we comment on the article titled“Inflammatory bowel diseases patients suffer from significant low levels and barriers to physical activity:The BE-FIT-IBD study”published in a recent issue of the World Journal of Gastroen-terology 2023;29(41):5668-5682.Inflammatory bowel diseases(IBD)are emerging as a significant global health concern as their incidence continues to rise on a global scale,with detrimental impacts on quality of life.While many advances have been made regarding the management of the disease,physical inactivity in these patients represents an underexplored issue that may hold the key for further and better understanding the ramifications of IBD.Chronic pain,fatigue,and fear of exacerbating symptoms promotes physical inactivity among IBD patients,while the lack of clear guidelines on safe exercise regimens contributes to a norm of physical inactivity.Physical activity(PA)is accepted to have a positive effect on disease outcomes and quality of life,while inactivity exacerbates comorbidities like cardiovascular disease and mental health disorders.The“BE-FIT-IBD”study,focusing on PA levels and barriers in IBD patients of Southern Italy,revealed that a significant proportion(42.9%)were physically inactive.This lack of PA is attributed to barriers such as fear of flare-ups and misconceptions about exercise exacerbating the disease.The study also highlighted the need for better communication between healthcare providers and patients regarding the benefits of PA and safe incorporation into lifestyles.Moreover,physical inactivity may also contribute to disability in IBD patients,having a great impact on employment status.Of note is the fact that IBD also comes with an important psychological burden with relevant evidence suggesting that regular PA can improve mood,reduce anxiety,and enhance mental health.The“BE-FIT-IBD”study advocated for the integration of PA into IBD management,emphasizing the bidirectional link between PA and IBD.Regular exercise can influence the course of IBD,potentially reducing symptom severity and prolonging remission periods.As such,it is mandatory that healthcare providers actively educate patients,dispel misconceptions,and tailor exercise recommendations to improve the quality of life and reduce IBD-related complications.

Unveiling hidden outcomes in malignant gastric outlet obstruction research–insights from a"Pancreas 2000"review

Malignant gastric outlet obstruction(mGOO)is a major condition affecting patients with periampullary tumors,including pancreatic cancer.The current treatment options include surgical gastroenterostomy,endoscopic stenting and more recently EUS-guided gastroenterostomy.Most studies comparing the outcomes of the three procedures focus on technical success,clinical success and safety.Several“occult”outcomes relevant to the patient’s viewpoints and perspective may ultimately impact on cancer-related and overall survival,such as body mass composition,nutritional biomarkers,chemotherapy tolerance and patient-reported quality of life.The aim of this review is to provide an overview of potential key outcomes that should be explored in future comparative research around mGOO treatment options.

Sarcopenic obesity in patients awaiting liver transplant: Unique challenges for nutritional recommendations

Sarcopenic obesity increases the risk of mortality in patients with liver disease awaiting liver transplantation and in the post-transplant period.Nutrition recommendations for individuals with sarcopenia differ from recommendations for patients with obesity or sarcopenic obesity.While these nutrition guidelines have been established in non-cirrhotic patients,established guidelines for liver transplant candidates with sarcopenic obesity are lacking.In this paper,we review existing literature on sarcopenic obesity in patients with chronic liver disease and address opportunities to improve nutritional counseling in patients awaiting liver transplantation.

Muscle Mass Is Associated with Depression in Adolescents and Young Adults

Background and Aims: The study aims to explore the association between body composition and depression in adolescents and young adults. Methods: A random cluster sampling method was used to select 41 age-matched indi-viduals (aged 11 - 30) as a non-depressive control group. The Department of Psychology at the Affiliated Hospital of Youjiang Medical University for Na-tionalities recruited 27 depressive patients within the same age range. Bioelec-trical impedance analysis measured body composition, while SCL-90, SAS, and SDS were employed for depression diagnosis. Logistic regression analysis was conducted to assess the relationship between body composition and de-pression scores. Results: The Depression Group exhibited higher levels of fat mass (p Conclusion: Depression is associated with age, gender, and muscle mass in adolescents and young people. Proper exercise and a healthy diet can increase muscle mass, thereby reducing fat mass and, as a result, reducing the prevalence of depression.

The Association of Maternal Body Composition and Dietary Intake with the Risk of Gestational Diabetes Mellitus during the Second Trimester in a Cohort of Chinese Pregnant Women

Objective To investigate the association of maternal body composition and dietary intake with the risk of gestational diabetes mellitus （GDM）. Methods A total 154 GDM subjects and 981 controls were enrolled in a prospective cohort study in 11 hospitals from May 20, 2012 to December 31, 2013. Bioelectrical impedance analysis and dietary surveys were used to determine body composition and to evaluate the intake of nutrients in subjects at 21-24 weeks＇ gestation （WG）. Logistic regression analysis was applied to explore the relationships of maternal body composition and dietary intake with the risk of GDIVl morbidity. Results Age, pre-pregnant body weight （BW）, and body mass index （BMI） were associated with increased risk of GDM. Fat mass （FM）, fat mass percentage （FMP）, extracellular water （ECW）, BMI, BW, energy, protein, fat, and carbohydrates at 21-24 WG were associated with an increased risk of GDM. In contrast, fat free mass （FFM）, muscular mass （MM）, and intracellular water （ICW） were associated with a decreased risk of GDM. Conclusion Maternal body composition and dietary intake during the second trimester of pregnancy were associated with the risk of GDM morbidity.

Effects of the Dietary Probiotic Clostridium butyricum on Intestine Digestive and Metabolic Capacities, SCFA Content and Body Composition in Marsupenaeus japonicus

A 56-day feeding trial was performed to evaluate the effects of dietary probiotic Clostridium butyricum(CB) on intestine digestive and metabolic capacities, intestine short-chain fatty acids(SCFA) content and body composition of kuruma shrimp Marsupenaeus japonicus. Shrimp s were randomly allocated into 9 tanks, 30 each, and f ed with diets containing different levels of C. butyricum(1×10~9 cfug^(-1)): 0 mgg^(-1) feed(Control), 100 mgg^(-1) feed(CB-100), 200 mgg^(-1) feed(CB-200), while each level was triplicated. The results indicated that compared with the control group, the intestine pepsin(Pep) activity and 5-hydroxytryptamine(5-HT) concentration of two C. butyricum group s were both increased. Amylase(AM Y) and lipase(LPS) activities wer e only induced in CB-200 group. Alanine aminotransferase(ALT) and aspartate aminotransferase(A ST) activities of two C. butyricum group s showed no significant change. The α-amylase(AM Y) gene expression was induced in CB-200 group, and tryp sin gene expression of two C. butyricum treated group s were both induced. Intestine SCFA content and body composition analysis showed that the contents of propionic acid, butyric acid and the crude protein of two C. butyricum group s were all higher than those of control. These results revealed that C. butyricum can modulate intestine digestive and metabolic capacities, improve intestine SCFA content and body crude protein content in M. japonicus.

Influence of stocking density on growth, body composition and energy budget of Atlantic salmon Salmo salar L. in recirculating aquaculture systems

Atlantic salmon Salmo salar were reared at four stocking densities--high density D1 （final density -39 kg/m^3）, medium densities DE （-29 kg/m^3） and D3 （~19 kg/m^3）, and low density D4 （-12 kg/m^3）- for 40 days to investigate the effect of stocking density on their growth performance, body composition and energy budgets. Stocking density did not significantly affect specific growth rate in terms of weight （SGRw） but did affect specific growth rate in terms of energy （SGRe）. Stocking density significantly influenced the ration level （RLw and RLe）, feed conversion ratio （FCRw and FCRe） and apparent digestibility rate （ADR）. Ration level and FCRw tended to increase with increasing density. Fish at the highest density D~ and lowest density D4 showed lower FCRe and higher ADR than at medium densities. Stocking density significantly affected protein and energy contents of the body but did not affect its moisture, lipid, or ash contents. The expenditure of energy for metabolism in the low-density and high-density groups was lower than that in the medium-density groups. Stocking density affected energy utilization from the feces but had no effect on excretion rate. The greater energy allocation to growth at high density and low density may be attributed to reduced metabolic rate and increased apparent digestibility rate. These findings provide information that will assist selection of suitable stocking densities in the Atlantic-salmon-farming industry.

Body Mass Index and Body Fat Percentage in Assessment of Obesity Prevalence in Saudi Adults

Objective To assess the obesity prevalence in body mass index （BMI） and body fat percentage Saudi adults according to the international standards of （BF%）. Methods Five hundred and thirty healthy Saudi adults aged 18-72 years （mean 36.91＋15.22 years） were enrolled in this study. Their body composition was assessed by bioelectrical impendence analysis with a commercially available body composition analyzer. Standard BMI and BF% values were used to define obesity. Results The prevalence of underweight, normal underweight, overweight and obesity in Saudi adults according to the BMI criteria （〈18.5 kg/mz, 18.5-24.4 kg/m2, 25-29.9 kg/m2, 30 k＆/m2 and above, respectively） was 2.5%, 30.2%, 33.6%, and 33.8%, respectively, whereas the obesity prevalence was 60% （n=31g） in Saudi adults according to the BF% criteria （25% for males and 30% for females）, which was significantly higher than that according to BMI criteria. However, it was 50.6% （n=268） when the BMI cutoff point was 27.5 kg/m2, proposed by WHO for the Asian population. Kappa analysis showed that the obesity prevalence defined by BMI and BF% was higher in females than in males （k=0.530 vs k=0.418, P〈O.O001）. The sensitivity and specificity of BMI （30 kg/m2 and 27.5 kg/m2） were 54.1% and 96.7% and 76.4% and 88.2%, respectively, for obesity. A lower BMI cutoff point （26.60 kg/m2） was proposed in this study, which gave the maximum sensitivity （84.3%） and specificity （85.4%）, with a moderate kappa agreement （k=0.686）. Moreover, the obesity prevalence at this cutoff point （56.4%） was significantly higher than that recommended by WHO. Conclusion The specificity of BMI for obesity is high and its sensitivity is low in both sexes. Its sensitivity can be increased by changing BMI cutoff to a lower value. The choice of BF% reference is of great influence for the assessment of obesity prevalence according to the BMI.

Effects of chromium nanoparticle dosage on growth,body composition,serum hormones and tissue chromium in Sprague-Dawley rats

This 6-week study was conducted to evaluate the effects of seven different levels of dietary chromium (Cr) (0,75,150,300,450,600,and 1200 ppb Cr) in the form of Cr nanoparticle (CrNano) on growth,body composition,serum hormones and tissue Cr in Sprague-Dawley (SD) rats. Seventy male SD rats (average initial body weight of (83.2±4.4) g) were randomly assigned to seven dietary treatments (n=10). At the end of the trial,body composition was assessed via dual energy X-ray absorptiometry (DEXA). All rats were then sacrificed to collect samples of blood,organs and tissues for determination of serum hormones and tissue Cr contents. The results indicated that lean body mass was significantly increased (P<0.05) due to the addition of 300 and 450 ppb Cr from CrNano. Supplementation of 150,300,450,and 600 ppb Cr decreased (P<0.05) percent body fat significantly. Average daily gain was increased (P<0.05) by addition of 75,150,and 300 ppb Cr and feed efficiency was increased (P<0.05) by supplementation of 75,300,and 450 ppb Cr. Addition of 300 and 450 ppb Cr decreased (P<0.05) the insulin level in serum greatly. Cr contents in liver and kidney were greatly increased (P<0.05) by the addition of Cr as CrNano in the dosage of from 150 ppb to 1 200 ppb. In addition,Supplementation of 300,450,and 600 ppb Cr significantly increased (P<0.05) Cr content in the hind leg muscle. These results suggest that supplemental CrNano has beneficial effects on growth performance and body composition,and increases tissue Cr concentration in selected muscles.

Composite Sand Bodies Architecture of Deep-Water Turbidite Channels in the Niger Delta Basin

Deep-water turbidite channels have attracted much attention as a focused issue in petroleum exploration and development. Extensive studies have been performed on the architecture of turbidite channels, and most researches have focused on their geometric shapes, sedimentary processes and controlling factors. However, little attention has been paid to the distribution patterns, distribution laws and quantitative studies of composite sand bodies of turbidite channels. Taken one slope area of the Niger Delta Basin as an example, this study conducted a semi-quantitative to quantitative analysis on architecture of composite sand bodies of turbidite channels based on cores, well logging and seismic surveys. It is shown that turbidite channel systems can be classified as confined and unconfined channel systems. For confined channel systems, the vertical evolution process involves four stages. The sinuosity of a channel system is controlled by slope, with a negative power function relationship between them. When slope gradient reaches four degrees, the channel system is nearly straight. Based on the migration direction and migration amount of single channels within channel complexes, channel composite patterns can be divided into four classes（the lateral composite, en-echelon composite, swing composite and vertical composite） and several subclasses. Various channel composite patterns show specific distribution laws spatially. For meandering channel complexes at the middle-late evolution stage of confined channel systems, the lateral migration amongst single channels shows the features of integrity and succession. The sinuosity of single channels in the late period is greater than that in the early period, and cut-offs may occur locally when the sinuosity is larger than five degrees. This study provides a better understanding for the geological theory of deep-water sedimentary, and also improves exploitation benefits of this type of reservoirs.

Experimental and numerical study of coal-rock bimaterial composite bodies under triaxial compression

To accurately predict coal burst hazards and estimate the failure of coal pillars in underground coal mining systems,it is of great significance to understand the mechanical behavior of coal-rock bimaterial composite structures.This paper presents experimental and numerical investigations on the response of rock-coal,coal-rock,and rock-coal-rock bimaterial composite structures under triaxial compression.The triaxial compression experiments are conducted under confining pressures in the range of 0-20 MPa.The resulting inside fracture networks are detected using X-ray-based computed tomography(CT).The experimentally observed data indicate that the mechanical parameters of the rock-coalrock composites are superior to those of the rock-coal and coal-rock combinations.After compression failure,the coal-rock combination specimens are analyzed via X-ray CT.The results display that the failure of the coal-rock composite bodies primarily takes place within the coal.Further,the bursting proneness is reduced by increasing confining pressure.Subsequently,the corresponding numerical simulations of the experiments are carried out by using the particle flow code.The numerical results reveal that coal is vulnerable with regard to energy storage and accumulation.

Effect of dietary genistein on growth performance,digestive enzyme activity,and body composition of Nile tilapia Oreochromis niloticus

An 8-week feeding experiment was performed to evaluate the effect of dietary genistein on growth performance,body composition,and digestive enzymes activity of juvenile Nile tilapia(Oreochromis niloticus).Four isonitrogenous and isoenergetic diets were formulated containing four graded supplements of genistein:0,30,300,and 3 000 μg/g.Each diet was randomly assigned in triplicate to tanks stocked with 15 juvenile tilapia(10.47±1.24 g).The results show that 30 and 300 μg/gdietary genistein had no significant effect on growth performance of Nile tilapia,but the higher level of genistein(3 000 μg/g)significantly depressed the final body weight and specific growth rate.There was no significant difference in survival rate,feed intake,feed efficiency ratio or whole body composition among all dietary treatments.An assay of digestive enzymes showed that the diet containing 3 000 μg/ggenistein decreased stomach and hepatopancreas protease activity,and amylase activity in the liver and intestine,while a dietary level of300 μg/g genistein depressed stomach protease and intestine amylase activities.However,no significant difference in stomach amylase activity was found among dietary treatments.Overall,the results of the present study indicate that a high level of dietary genistein(3 000 μg/g,or above) would significantly reduce the growth of Nile tilapia,partly because of its inhibitory effect on the activity of major digestive enzymes.Accordingly,the detrimental effects of genistein,as found in soybean products,should not be ignored when applied as an alternative ingredient source in aquaculture.