Changes in soil aggregate stability and aggregate-associated carbon under different slope positions in a karst region of Southwest China

Soil aggregates are crucial for reducing soil erosion and enhancing soil organic carbon sequestration. However, knowledge regarding influences of different slope positions on compositions and carbon content for different soil aggregates is limited. Soil samples were collected from various slope positions including dip slope, anti-dip slope and valley depression in the Longtan karst valley of Southwest China. Contents of macroaggregate (> 0.25 mm), microaggregate (0.053-0.25 mm) and silt and clay fraction (< 0.053 mm), and aggregate-associated carbon contents under the three slope positions were measured. Compared to the anti-dip slope, the mean weight diameter under the dip slope and valley depression decreased by 28.48 % and 58.79 %, respectively, while the geometric mean diameter decreased by 39.01 % and 62.57 %, respectively. The mean carbon content in silt and clay fraction was 27.59 % and 21.00 % lower than the macroaggregate- and microaggregate-associated carbon content, respectively. Under the valley depression and dip slope, soil organic carbon contents in bulk soil (37.67 % and 10.36 %, respectively), microaggregate (37.56 % and 4.95 %), and silt and clay fraction (39.99 % and 12.84 %, respectively) were significantly lower than those under the anti-dip slope. However, the difference in macroaggregate-associated carbon content among the three slope positions was not significant. The silt and clay fraction was the major contributor to soil carbon pool in bulk soil in the study area because of its high content. Compared to the anti-dip slope, contribution of macroaggregates to soil carbon pool under the dip slope and valley depression decreased by 25.53 % and 47.95 %, respectively, whereas the contribution of silt and clay fraction increased by 22.68 % and 42.66 %, respectively. These results suggested that the anti-dip slope surpassed both the dip slope and valley depression in carbon sequestration and soil and water conservation in karst regions.

Variation of the Start Date of the Vegetation Growing Season (SOS) and Its Climatic Drivers in the Tibetan Plateau

Climate change inevitably affects vegetation growth in the Tibetan Plateau (TP). Understanding the dynamics of vegetation phenology and the responses of vegetation phenology to climate change are crucial for evaluating the impacts of climate change on terrestrial ecosystems. Despite many relevant studies conducted in the past, there still remain research gaps concerning the dominant factors that induce changes in the start date of the vegetation growing season (SOS). In this study, the spatial and temporal variations of the SOS were investigated by using a long-term series of the Normalized Difference Vegetation Index (NDVI) spanning from 2001 to 2020, and the response of the SOS to climate change and the predominant climatic factors (air temperature, LST or precipitation) affecting the SOS were explored. The main findings were as follows: the annual mean SOS concentrated on 100 DOY-170 DOY (day of a year), with a delay from east to west. Although the SOS across the entire region exhibited an advancing trend at a rate of 0.261 days/year, there were notable differences in the advancement trends of SOS among different vegetation types. In contrast to the current advancing SOS, the trend of future SOS changes shows a delayed trend. For the impacts of climate change on the SOS, winter Tmax (maximum temperature) played the dominant role in the temporal shifting of spring phenology across the TP, and its effect on SOS was negative, meaning that an increase in winter Tmax led to an earlier SOS. Considering the different conditions required for the growth of various types of vegetation, the leading factor was different for the four vegetation types. This study contributes to the understanding of the mechanism of SOS variation in the TP.

Erratum: Ubiquitous Non-Majorana Zero-Bias Conductance Peaks in Nanowire Devices [Phys. Rev. Lett. 123, 107703 (2019)]

This corrects the article DOI: 10.1103/PhysRevLett.123.107703.

[Investigating ocular parameters for predicting anomalous vault among phakic intraocular lens patients]

Objective: To analyze the relationships between preoperative ocular parameters and postoperative anomalous vaults, and research their predictive diagnostic value. Methods: In this retrospective case series study, 664 eyes from 332 patients underwent posterior chamber phakic intraocular lens (pIOL) implantation at Shanghai Bright Eye Hospital and Wuxi Huaxia Eye Hospital from November 2020 to November 2021. Preoperative ocular parameters, including spherical equivalent, intraocular pressure, horizontal/vertical ciliary sulcus diameters (HCS/VCS), white-to-white diameters (WTW), corneal steep/flat curvature, central corneal thickness, anterior chamber depth (ACD), lens thickness (LT), and axial length were collected. The pIOL vaults were measured 3 months after surgery. Patients were categorized into low vault group, optimal vault group, and high vault group based on whether the vault fell within the ideal range (250 to 750 μm). Using the optimal vault group as a benchmark, receiver operating characteristic (ROC) curves were drawn for each ocular parameter of the low and high vault groups to analyze diagnostic efficiency and cut-off values for abnormal vaults after pIOL operation. Each ocular parameter was used as an independent variable to establish a multivariate logistic regression model for two different vault anomalies. ROC curves were drawn and analyzed again based on the regression results. Results: Statistically significant differences were observed in WTW, HCS-WTW, ACD, and LT among the three groups. Comparisons between each pair of groups indicated that WTW in the high vault group significantly differed from the other two groups (P<0.05), HCS-WTW in the low vault group significantly differed from the other groups (P<0.05), and ACD and LT explained statistical differences among the three groups (P<0.05), while other parameters showed no differences. ROC curves illustrated that independent ocular parameters such as LT, HCS-WTW, and ACD had clinical predictive diagnostic significance for low vault abnormalities. The area under the curve (AUC), sensitivity, and specificity for these parameters were 0.829(0.952, 0.561), 0.745(0.857, 0.644), and 0.730(0.619, 0.853), respectively. The diagnostic cut-off values were 3.745, 0.020, and 2.975 mm, respectively. The clinical predictive significance of independent ocular parameters in diagnosing the high vault group was poor (AUC<0.7). The predictive Logistic model equation for low vault was Logistic(V1)=-10.067+5.328·HCS-3.620·WTW+6.263·LT, and the predictive model for high vault was Logistic(V2)=6.232+1.323·WTW-3.358·LT. The new parameters in the predictive equation significantly improved the diagnostic efficiency of low and high vault abnormalities, reaching 0.884(0.810, 0.824) and 0.736(0.810, 0.554), respectively. Conclusions: Preoperative predictive diagnostic parameters for postoperative low vault group included LT, HCS-WTW, and ACD, while the high vault group had no independent predictive diagnostic parameters. Logistic regression improved the predictive diagnostic efficiency of abnormal vaults.

[Advances in clinical significance and detection methods research of high density lipoprotein subfractions]

High density lipoprotein (HDL) is an important biochemical index of clinical cardiovascular disease. Many new studies have demonstrated abnormalities of plasma HDL subfractions in patients with this disease,and their clinical significance is greater than the overall abnormalities of HDL. Therefore,the HDL subfraction as an important factor in cardiovascular disease has attracted extensive research and attention. This article summarizes current research on HDL subfractions,their measurements and their relationships with atherosclerosis and coronary artery disease.

[Clinical value of nomogram model in evaluating the prognosis of cholangiocarcinoma after interventional therapy]

Objective: To investigate the clinical value and efficacy of the nomogram model in evaluating the prognosis of cholangiocarcinoma after interventional therapy. Methods: The clinical data of 259 patients with cholangiocarcinoma who received interventional therapy at the First Affiliated Hospital of zhengzhou University from January 2014 to June 2021 were retrospectively analyzed, including 148 males and 111 females, aged from 26 to 91 (65±12) years. They were randomly divided into a training group (181 cases) and a validation group (78 cases) in a ratio of 7∶3. Cox regression analysis was performed in the training group, independent risk factors affecting the prognosis of patients were screened, and a nomogram for 6-month, 1-year, and 2-year survival was constructed. The performance of the nomogram was analyzed by calculating the area under the receiver operating characteristic curve (AUC) value, calibration curve, and decision curve, and the predictive efficacy of the model was evaluated in the validation group. Results: There was no significant difference in baseline data between the training group and the validation group, which was comparable. Regression analysis showed that T stage (T2: HR=0.147,95%CI: 0.077-0.281;T3: HR=0.207,95%CI: 0.122-0.351;T4: HR=0.864,95%CI: 0.537-1.393), tumor diameter (17-33 mm: HR=0.201,95%CI: 0.119-0.341;≥33 mm: HR=0.795,95%CI: 0.521-1.211) and differentiation degree(middle differentiation: HR=3.318,95%CI: 2.082-5.289;highly differentiation: HR=1.842,95%CI: 1.184-2.867) were risk factors affecting the prognosis of interventional therapy for cholangiocarcinoma. The AUC values of the survival curve prediction models were generally consistent between the training and validation groups, and the AUC values of the training group at 6 months, 1 year, and 2 years were 0.925 (95%CI: 0.888-0.963), 0.921 (95%CI: 0.877-0.964) and 0.974 (95%CI: 0.957-0.993), respectively. In the validation group, the 6-month, 1-year, and 2-year AUC values were 0.951 (95%CI: 0.911-0.991), 0.917 (95%CI: 0.857-0.977) and 0.848 (95%CI: 0.737-0.959), respectively, and the AUC values were all greater than 0.8, suggesting that the nomogram had better discrimination ability. The calibration curves of the prediction models of the two groups were basically consistent, and the shape of the calibration curves at 6 months and 1 year fitted the ideal curve, while the fitting degree of the calibration curves at 2 years was relatively poor. The decision curve showed the high clinical utility of this nomogram in predicting the 6-month, 1-year survival of patients with cholangiocarcinoma. Conclusions: T stage, tumor diameter, and differentiation are independent risk factors affecting the prognosis of patients with interventional cholangiocarcinoma, and the nomogram model proposed in this study has good distinguishing ability and exact clinical value for prognosis evaluation.

Increasing temperature regulates the advance of peak photosynthesis timing in the boreal ecosystem

The shift in vegetation phenology is an essential indicator of global climate change. Numerous researches based on reflectance-based vegetation index data have explored the changes in the start (SOS) and end (EOS) of vegetation life events at long time scales, while a huge discrepancy existed between the phenological metrics of vegetation structure and function. The peak photosynthesis timing (PPT), which is crucial in regulating terrestrial ecosystem carbon balance, has not received much attention. Using two global reconstructed solar-induced chlorophyll fluorescence data (CSIF and GOSIF) directly associated with vegetation photosynthesis, the spatio-temporal dynamics in PPT as well as the key environmental controls across the boreal ecosystem during 2001-2019 were systematically explored. Multi-year mean pattern showed that PPT mainly appeared in the first half of July. Compared to the northern Eurasia, later PPT appeared in the northern North America continent for about 4-5 days. Meanwhile, spatial trend in PPT exhibited an advanced trend during the last two decades. Especially, shrubland and grassland were obvious among all biomes. Spatial partial correlation analysis revealed that preseason temperature was the dominant environmental driver of PPT trends, occupying 81.32% and 78.04% of the total pixels of PPT_CSIF and PPT_GOSIF, respectively. Attribution analysis by ridge regression again emphasized the largest contribution of temperature to PPT dynamics in the boreal ecosystem by 52.22% (PPT_CSIF) and 46.59% (PPT_GOSIF), followed by radiation (PPT_CSIF: 24.44%; PPT_GOSIF: 28.66%) and precipitation (PPT_CSIF: 23.34%; PPT_GOSIF: 24.75%). These results have significant implications for deepening our understanding between vegetation photosynthetic phenology and carbon cycling with respect to future climate change in the boreal ecosystem.

Octahedral Distortion and Displacement-Type Ferroelectricity with Switchable Photovoltaic Effect in a 3d^{3}-Electron Perovskite System

Because of the half-filled t_{2g}-electron configuration, the BO_{6} octahedral distortion in a 3d^{3} perovskite system is usually very limited. In this Letter, a perovskitelike oxide Hg_{0.75}Pb_{0.25}MnO_{3} (HPMO) with a 3d^{3} Mn^{4+} state was synthesized by using high pressure and high temperature methods. This compound exhibits an unusually large octahedral distortion enhanced by approximately 2 orders of magnitude compared with that observed in other 3d^{3} perovskite systems like RCr^{3+}O_{3} (R=rare earth). Essentially different from centrosymmetric HgMnO_{3} and PbMnO_{3}, the A-site doped HPMO presents a polar crystal structure with the space group Ama2 and a substantial spontaneous electric polarization (26.5  μC/cm^{2} in theory) arising from the off-center displacements of A- and B-site ions. More interestingly, a prominent net photocurrent and switchable photovoltaic effect with a sustainable photoresponse were observed in the current polycrystalline HPMO. This Letter provides an exceptional d^{3} material system which shows unusually large octahedral distortion and displacement-type ferroelectricity violating the "d^{0}-ness" rule.

Restored vegetation is more resistant to extreme drought events than natural vegetation in Southwest China

Large scale Ecosystem restoration projects (ERPs) have been implemented to restore vegetation and increase carbon stocks across China. However, whether restored vegetation is strongly resistant to Extreme drought events (EDEs) remains unclear, especially when compared to natural vegetation. Therefore, we used the standardized anomaly of 3-month Standard Precipitation-Evapotranspiration Index (SPEI) to characterize the spatial-temporal trends of EDEs, and figured out the capacity of restored vegetation to withstand the strongest EDE in Southwest China by analyzing their changes of Gross Primary Productivity (GPP) and Water Use Efficiency (WUE). The results showed that Southwest China had experienced six typical EDEs with increasing frequency and severity from 1982 to 2017, particularly the EDE during 2009-2010 (EDE 2009/2010) which had the longest duration and strongest severity. Overall, the EDE 2009/2010 substantially suppressed the vegetation GPP and ecosystem WUE in both restored and natural vegetation area. Compared with natural vegetation, the GPP and WUE of restored vegetation was relative higher and moreover, their GPP decreased more slowly during the EDE 2009/2010 and increased more quickly during the recovery period. This indicates that restored vegetation had a higher drought resistance to the EDE than natural vegetation. Additionally, karst landforms have a stronger negative impact on vegetation GPP and WUE during the EDE. Furthermore, the reduction in the afforestation areas was more obviously observed than that in natural forest areas. Therefore, we suggest that vegetation suitable for regional characteristics should be selected during vegetation restoration, such as afforestation in the non-karst areas.

Pyrocumulonimbus affect average stratospheric aerosol composition

Pyrocumulonimbus (pyroCb) are wildfire-generated convective clouds that can inject smoke directly into the stratosphere. PyroCb have been tracked for years, yet their apparent rarity and episodic nature lead to highly uncertain climate impacts. In situ measurements of pyroCb smoke reveal its distinctive and exceptionally stable aerosol properties and define the long-term influence of pyroCb activity on the stratospheric aerosol budget. Analysis of 13 years of airborne observations shows that pyroCb are responsible for 10 to 25% of the black carbon and organic aerosols in the "present-day" lower stratosphere, with similar impacts in both the North and South Hemispheres. These results suggest that, should pyroCb increase in frequency and/or magnitude in future climates, they could generate dominant trends in stratospheric aerosol.

Development and validation of risk prediction models for stroke and mortality among patients with type 2 diabetes in northern China

BACKGROUND

Stroke is one of the leading causes of disability and mortality in patients with type 2 diabetes mellitus (T2DM). Risk models have been developed for predicting stroke and stroke-associated mortality among patients with T2DM. Here, we evaluated risk factors of stroke for individualized prevention measures in patients with T2DM in northern China.

METHODS

In the community-based Tianjin Chronic Disease Cohort study, 58,042 patients were enrolled between January 2014 and December 2019. We used multiple imputation (MI) to impute missing variables and univariate and multivariate Cox's proportional hazard regression to screen risk factors of stroke. Furthermore, we established and validated first-ever prediction models for stroke (Model 1 and Model 2) and death from stroke (Model 3) and evaluated their performance.

RESULTS

In the derivation and validation groups, the area under the curves (AUCs) of Models 1-3 was better at 5 years than at 8 years. The Harrell's C-index for all models was above 0.7. All models had good calibration, discrimination, and clinical net benefit. Sensitivity analysis using the MI dataset indicated that all models had good and stable prediction performance.

CONCLUSION

In this study, we developed and validated first-ever risk prediction models for stroke and death from stroke in patients with T2DM, with good discrimination and calibration observed in all models. Based on lifestyle, demographic characteristics, and laboratory examination, these models could provide multidimensional management and individualized risk assessment. However, the models developed here may only be applicable to Han Chinese.

Sex Specific Global Burden of Osteoporosis in 204 Countries and Territories, from 1990 to 2030: An Age-Period-Cohort Modeling Study

BACKGROUND

Osteoporosis is a highly prevalent disease with distinct sex pattern. We aimed to estimate the sex specific incidence, prevalence, and disability-adjusted life (DALYs) years of osteoporosis between 1990 and 2019, with additional predictions from 2020 to 2034.

METHODS

We collected osteoporosis disease burden data from the Global Burden of Disease study covering the years 1990 through 2019 in 204 countries and territories. The data included information on the number of incident cases of osteoporosis, DALYs, age-standardized incidence rates (ASIR), age-standardized prevalence rates (ASPR) and age-standardized DALYs rates. Additionally, we performed an age-period-cohort analysis to forecast the burden of osteoporosis.

RESULTS

The global number of incidence cases of osteoporosis, in 2019, reached 41.5 million cases. From 1990 to 2019, the low-middle socio-demographic index (SDI) region had the highest estimated annual percentage change in the world. Compared to males, female's ASIR and ASPR were all about 1.5 times higher than males for the same years in the same SDI regions. The projected global total number of incidence cases for osteoporosis between 2030 and 2034 is estimated to reach 263.2 million (154.4 million for females and 108.8 for males). Additionally, the burden in terms of DALYs is predicted to be 128.7 million (with 78.4 million for females and 50.3 million for males).

CONCLUSION

The global burden of osteoporosis is still increasing, mainly observed in high SDI countries. Females bear a burden 1.5 times higher than males in terms of incidence and DALYs. Steps should be taken to reduce the osteoporosis burden, especially in high SDI countries.

Clinical feasibility of deep learning-based automatic head CBCT image segmentation and landmark detection in computer-aided surgical simulation for orthognathic surgery

The purpose of this ambispective study was to investigate whether deep learning-based automatic segmentation and landmark detection, the SkullEngine, could be used for orthognathic surgical planning. Sixty-one sets of cone beam computed tomography (CBCT) images were automatically inferred for midface, mandible, upper and lower teeth, and 68 landmarks. The experimental group included automatic segmentation and landmarks, while the control group included manual ones that were previously used to plan orthognathic surgery. The qualitative analysis of segmentation showed that all of the automatic results could be used for computer-aided surgical simulation. Among these, 98.4% of midface, 70.5% of mandible, 98.4% of upper teeth, and 93.4% of lower teeth could be directly used without manual revision. The Dice similarity coefficient was 96% and the average symmetric surface distance was 0.1 mm for all four structures. With SkullEngine, it took 4 minutes to complete the automatic segmentation and an additional 10 minutes for a manual touchup. The results also showed the overall mean difference between the two groups was 2.3 mm for the midface and 2.4 mm for the mandible. In summary, the authors believe that automatic segmentation using SkullEngine is ready for daily practice. However, the accuracy of automatic landmark digitization needs to be improved.

PSVIII-19 Predict Indigestible Fiber Fraction of Barley Plant Silage by Using non-Destructive Mid-IR vs Near-IR Spectroscopic Techniques

The objective of this study was to reveal the potential of using Fourier transform mid-infrared (FTIR) and near infrared (NIR) spectroscopy as tools for the determination of indigestible neutral (NDF) fraction (iNDF) of barley plant silage. A total of 48 barley plant silage samples collected from different farms in Western Canada provinces were analyzed for iNDF. Reference values were matched with NIR and FTIR spectra. Spectral data processing (pretreatments) included first derivative (FD), standard normal variate (SNV), multiplicative scattering correction (MSC), second derivative (SD) and orthogonal signal correction (OSC). Prediction equations were obtained from each model using an external validation set. The determination coefficient of external validation (R2P) of iNDF was 0.62 for FTIR, while 0.41 for NIR and the corresponding ratio performance deviation (RPD) were 1.69 and 1.38 in FTIR and NIR, respectively. Results from this research showed the high potential of applying infrared molecular spectroscopy for the examination of forage plant fiber digestibility. More studies are needed to improve the accuracy and performance of FTIR and NIR spectroscopies in predicting the iNDF of barley plant silage samples.

PSXIII-12 Characterization of Physiochemical and Nutrient Profiles of Feedstock and co-Products from Canola bio-oil Processing in Ruminants: Impacted by Source Origin

The objective of this study was to characterize physiochemical and nutrient profiles of feedstock and co-products from canola processing that were impacted by source origin to compare feedstocks and co-products (mash and pellet) from five different bio-oil processing plants with five batches of samples in each processing plant in Canada (CA) and in China (CH) collected by the Canola Council of Canada (CCC). The detailed physicochemical and nutrients parameters for ruminants were determined in chemical composition, TDN and truly digestible nutrients, energy profile (ME, NE), and protein and carbohydrate subfractions and their degradation and digestion in dairy cows. The data were analyzed using the Mixed model procedure in SAS 9.4 with RCBD. The treatment differences were compared using Tukey method. The results showed CP was greater in CH meals (P=0.003). The EE was not different between CA and CH (P &gt;0.05). TDN1x was similar in canola meals regardless of the country (P &gt;0.05). CH meals and feedstock had greater tdCP and tdNDF than CA (P&lt; 0.05), while CA had greater tdNFC (P&lt; 0.05). The energy values of ME3x, NELp3x, NEm3x, and NEg3x were similar in canola meals from both countries (P &gt;0.05). No differences were observed in the energy profile of feedstock between CA and CH (P &gt;0.05). The results also showed that pelleting affected the protein fractionation of CA canola meals (P&lt; 0.05). Canola meals were different between CA and CH in the soluble (PA2) and slowly degradable fractions (PB2) (P&lt; 0.05). The carbohydrate fractions of soluble fiber (CB2), digestible fiber (CB3), and indigestible fiber (CC) were different among CH meals (P&lt; 0.05). CH presented greater water-soluble carbohydrate (CA4, P=0.04) and less CB2 (P=0.01) and CC (P&lt; 0.001) than CA canola meals. Although the seeds were similar within and between counties, the oil-extraction process and pelleting seemed to have generated some different aspects on the meals in both countries.

PSI-18 Effect of Heat Processing Methods on Carbohydrate Subfractions and Degradation in Relation to Carbohydrate Molecular Spectral Profile of Barley Grain Using Advanced Molecular Spectroscopy in Ruminants

To our knowledge, there are few studies on the association between carbohydrate molecular structure spectral profiles of barley grain and ruminant-relevant nutritional characteristics. This study aimed to study associate processing-induced changes in carbohydrate molecular structure with changes in ruminant-relevant carbohydrate nutritional profiles. The heat processing methods included: dry roasting, autoclaving, and microwave irradiation. The ruminant-relevant carbohydrate nutritional profiles were determined which included carbohydrate chemical profiles, carbohydrate subfractions, ruminant-relevant carbohydrate digestion. The molecular structure spectral profiles were determined using vibrational molecular spectroscopy (ATR-FT/IR). The results showed that heat related processing significantly induced carbohydrate molecular spectral profiles. The heat related processing also significantly changed ruminant-relevant nutritional characteristics. There was an association between processing induced carbohydrate molecular structure changes and ruminant-relevant carbohydrate nutritional profiles. The advanced vibrational molecular spectroscopic technique (ATR-FTIR) shows the great potential as a fast analytical tool to predict ruminant-relevant carbohydrate nutritional characteristics.

Effects of vegetation succession on soil organic carbon fractions and stability in a karst valley area, Southwest China

A series of complex organic fractions with different physical and chemical properties make up soil organic carbon (SOC), which plays a vital role in climate change and the global carbon cycle. Different SOC fractions have different stability and respond differently to vegetation succession. This research was carried out to assess the impacts of vegetation succession on SOC dynamics in the Qingmuguan karst valley area, southwest China. Soil samples were collected from four typical vegetation succession stages, including farmland, grassland, shrubland, and forest. The total SOC content and four oxidizable SOC fractions were measured. Results showed that the total SOC content and storage under farmland were highest, followed by forest and shrubland, and the grassland had the lowest total SOC content and storage. The SOC sequestration potential under different vegetation types in the study area was grassland (26.32 Mg C ha^-1) > shrubland (9.64 Mg C ha^-1). All SOC content, storage, and fractions showed a decrease with the increase of soil depth over the 0-50 cm in the study area. The four SOC fractions under forest at topsoil (0-10 cm) were higher than that under the other vegetation types. Compared with the other land uses, the farmland had the highest stable oxidizable SOC fractions (F3 and F4) at the 10-50-cm depth, while the shrubland had the highest active oxidizable SOC fractions (F1 and F2). In terms of the lability index of SOC, shrubland was the largest, followed by grassland and forest, and farmland was the smallest. These results provide essential information about SOC fractions and stability changes resulting from changes of vegetation types in a karst valley area of southwest China. It also supplements our understanding of soil carbon sequestration in vegetation succession.

Anti-pathogen stainless steel combating COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exhibits strong stability on conventional stainless steel (SS) surface, with infectious virus detected even after two days, posing a high risk of virus transmission via surface touching in public areas. In order to mitigate the surface toughing transmission, the present study develops the first SS with excellent anti-pathogen properties against SARS-COV-2. The stabilities of SARS-CoV-2, H1N1 influenza A virus (H1N1), and Escherichia coli (E.coli) on the surfaces of Cu-contained SS, pure Cu, Ag-contained SS, and pure Ag were investigated. It is discovered that pure Ag and Ag-contained SS surfaces do not display apparent inhibitory effects on SARS-CoV-2 and H1N1. In comparison, both pure Cu and Cu-contained SS with a high Cu content exhibit significant antiviral properties. Significantly, the developed anti-pathogen SS with 20 wt% Cu can distinctly reduce 99.75% and 99.99% of viable SARS-CoV-2 on its surface within 3 and 6 h, respectively. In addition, the present anti-pathogen SS also exhibits an excellent inactivation ability for H1N1 influenza A virus (H1N1), and Escherichia coli (E.coli). Interestingly, the Cu ion concentration released from the anti-pathogen SS with 10 wt% and 20 wt% Cu was notably higher than the Ag ion concentration released from Ag and the Ag-contained SS. Lift buttons made of the present anti-pathogen SS are produced using mature powder metallurgy technique, demonstrating its potential applications in public areas and fighting the transmission of SARS-CoV-2 and other pathogens via surface touching.

Afforestation influences soil organic carbon and its fractions associated with aggregates in a karst region of Southwest China

Variations in soil organic carbon (SOC) and its fractions within soil aggregates in response to land-use change are important to understand the carbon cycles in terrestrial ecosystem. However, responses of total SOC, SOC fractions, and SOC stability in different soil aggregates to land-use change are less addressed, especially in karst regions with serious land degradation. Therefore, bulk soil samples were collected under four land uses with similar geographical characteristics and previous framing practices including farmland (FL), Bamboo forest (BA), landscape tree planting (LAT), and orange orchards (ORO) in a karst region of Southwest China. Contents of total SOC and three carbon fractions based on their degree of oxidizability (F1, very labile; F2, inert; F3, oxidizable resistant) in bulk soil and different soil aggregates (macro-aggregate, micro-aggregate, and silt+clay fraction) were measured. Afforestation significantly increased contents of total SOC and three carbon fractions in bulk soil and soil aggregates, and the influence was more obvious in macro-aggregate than the other aggregates. Contents of total SOC, F1, F2, and F3 under afforestation land increased by 41.73%, 58.19%, 33.91%, and 40.55%, respectively, in bulk soil, by 55.60%, 79.24%, 121.77%, and 43.30%, respectively, in macro-aggregate, by 52.80%, 33.57%, 20.14%, and 75.02%, respectively, in micro-aggregate, and by 26.21%, 35.60%, 29.26%, and 23.75%, respectively, in silt+clay fraction than those under FL. In bulk soil and soil aggregates, proportions of F1, F2, and F3 in total SOC ranged from 0.11 to 0.18, from 0.13 to 0.22, and from 0.60 to 0.73, respectively, suggesting that the stable carbon was the predominant carbon fraction in the study area. Afforestation decreased the values of stability of SOC in macro-aggregate and silt+clay fraction, while it increased the value in micro-aggregate. Although both BA and ORO had higher SOC content in bulk soil than the LAT, but the SOC stability in bulk soil under BA was significantly lower than that under ORO. In conclude, afforestation form FL improved SOC content and altered SOC stability in bulk soil and soil aggregates, and conversion of FL to ORO might be the best choice to increase SOC sequestration in the four land-use types compared in karst regions of Southwest China.

Conversion of alpine pastureland to artificial grassland altered CO2 and N2O emissions by decreasing C and N in different soil aggregates

BACKGROUND

The impacts of land use on greenhouse gases (GHGs) emissions have been extensively studied. However, the underlying mechanisms on how soil aggregate structure, soil organic carbon (SOC) and total N (TN) distributions in different soil aggregate sizes influencing carbon dioxide (CO₂), and nitrous oxide (N₂O) emissions from alpine grassland ecosystems remain largely unexplored.

METHODS

A microcosm experiment was conducted to investigate the effect of land use change on CO₂and N₂O emissions from different soil aggregate fractions. Soil samples were collected from three land use types, i.e., non-grazing natural grassland (CK), grazing grassland (GG), and artificial grassland (GC) in the Bayinbuluk alpine pastureland. Soil aggregate fractionation was performed using a wet-sieving method. The variations of soil aggregate structure, SOC, and TN in different soil aggregates were measured. The fluxes of CO₂ and N₂O were measured by a gas chromatograph.

RESULTS

Compared to CK and GG, GC treatment significantly decreased SOC (by 24.9-45.2%) and TN (by 20.6-41.6%) across all soil aggregate sizes, and altered their distributions among soil aggregate fractions. The cumulative emissions of CO₂ and N₂O in soil aggregate fractions in the treatments of CK and GG were 39.5-76.1% and 92.7-96.7% higher than in the GC treatment, respectively. Moreover, cumulative CO₂emissions from different soil aggregate sizes in the treatments of CK and GG followed the order of small macroaggregates (2-0.25 mm) > large macroaggregates (> 2 mm) > micro aggregates (0.25-0.053 mm) > clay +silt (< 0.053 mm), whereas it decreased with aggregate sizes decreasing in the GC treatment. Additionally, soil CO₂ emissions were positively correlated with SOC and TN contents. The highest cumulative N₂O emission occurred in micro aggregates under the treatments of CK and GG, and N₂O emissions among different aggregate sizes almost no significant difference under the GC treatment.

CONCLUSIONS

Conversion of natural grassland to artificial grassland changed the pattern of CO₂ emissions from different soil aggregate fractions by deteriorating soil aggregate structure and altering soil SOC and TN distributions. Our findings will be helpful to develop a pragmatic management strategy for mitigating GHGs emissions from alpine grassland.

Changes in soil aggregate stability and aggregate-associated organic carbon during old-field succession in karst valley

Soil is the largest carbon pool whose change will have an impact on the terrestrial carbon cycle in the terrestrial ecosystem. Old-field succession on abandoned farmland, which usually has a noticeable effect on soil status, is a common phenomenon in karst valley where human activity alters frequently. In order to understand the changes in the accumulation of organic carbon (OC) in aggregates and bulk soil in different stages of old-field succession on abandoned farmland in the karst valley area, soil samples were collected at 0-10-cm and 10-20-cm depth representing three typical stages of old-field succession, i.e., abandoned farmland, secondary grass, and secondary shrub in Qingmuguan karst valley area, Chongqing City, Southwest China. Results displayed that during old-field succession (1) the mean weight diameter and geometric mean diameter of the aggregates increased and the fractal dimension decreased; (2) OC content within aggregates and bulk soil had no significant change in topsoil (0-10 cm); OC content within microaggregates and bulk soil had a significant reduction in subsoil (10-20 cm); the OC content within silt and clay fractions was significantly higher than that within the other two kinds of aggregates; (3) bulk-soil OC storage had no significant change but its accumulation relied more on the increase in the number of larger aggregates. It is concluded that the old-field succession in karst valley was beneficial to protect against soil erosion by improving soil aggregate stability, but had a limited effect on soil organic carbon sequestration.

Ceramic Inlay Bonded Interfaces in Minimally Invasive Preparations: Damage and Contributing Mechanisms in Sliding Contact

BACKGROUND

In the preparation of inlay cavities, a choice must be made between conventional standard and minimally invasive preparation designs; in the long run, this choice can affect the integrity of the bonded interface.

PURPOSE

To evaluate the effect of minimally invasive cavity preparation designs on the extent and contributing mechanisms of damage to ceramic inlay bonded interfaces.

METHODS AND MATERIALS

Tooth blocks with 90°, 120° and 75° marginal angles were prepared, representing tooth cavities with conventional standard and minimally invasive preparations with large divergence and convergence angles and bonded to monolithic ceramic (IPS e.max CAD). Vickers indentations were placed at various distances from the bonded interface. The indentation morphology and crack length were observed. Reciprocating wear tests were performed on the bonded interface with a 20-newton (N) vertical load. The wear depth and wear-scar morphology were characterized after increments of cyclic sliding contact.

RESULTS

The 120° group exhibited longer indentation cracks in the ceramic, whereas the 75° group showed larger indentations in the enamel when compared to the 90° group (p<0.001). Consistent with the weaker edge crack resistance, the 120° group experienced the greatest wear (p=0.008), and the wear depth in the enamel of the 75° group exceeded that of the 90° group (p<0.001) in the early stage (5×102 cycles). However, no significant difference in the wear depth (p>0.147) and morphology were found at the later wear stage among the three groups.

CONCLUSION

Within the limitations of this study, minimally invasive preparations with 120° and 75° marginal angles can result in early sever damage at the ceramic inlay bonded interface but show comparable wear behaviors to the conventional 90° group at the later stage.

PSXIII-12 Exploring nutritional differences of canola seeds and bio-processing co-products (meals, pellets) from different processing plants/companies in Canada and China for dairy cattle

Canola was created as a low erucic acid and low glucosinolate seed, to produce high quality oil for human consumption and meal for use in livestock feed. China is an important user of Canadian canola products (seeds, oil, and meal). The extraction of the oil from the seed produces a co-product called canola meal. This meal is rich in protein and is used as a protein source in animal diets. However, differences in the characteristics of the seeds, or processing methods during oil extraction may affect the quality of this co-product. Plus, the synthesis of tissues and milk is related to the amino acids available to the animal for absorption in the small intestine. This study aimed to determine if there are significant differences in the intestinal digestibility (in vitro) of CP and DM between canola seeds and meals from different companies in Canada and to determine if there are significant differences between them in Canada and China. The three-step procedure was applied on residues from a 12-hour rumen incubation in fistulated dairy cows to estimate the intestinal digestibility of CP and DM. There were significant differences (P &lt; 0.05) for TDDM (Total digestible dry matter) and IDP (intestinal digestibility of protein) of the meals between countries. The samples from China had higher TDDM (83.76% versus 81.53%, P = 0.018), while Canada’s had higher IDP (68.51% versus 65.28%, P = 0.016). No significant differences were observed within countries. Based on the material analyzed during this study, it is safe to affirm that there are no significant differences in the digestibility of DM and CP between Canada and China. It was concluded that the quality of the canola seeds or meals produced in both Canada and China were similar when used in dairy rations.

Key words: canola seeds and bio-processing co-products (meals, pellets), nutritional differences, dairy cows

PSXVI-26 Using synchrotron/globar techniques to reveal synergistic and interactive association between molecular structures and nutrient supply in enzymatic and thermal treated oat tissue and whole grain

As an advanced technique, synchrotron radiation-based microspectroscopy SR-FTIRM has been a rapid, direct, non-destructive and non-invasive bioanalytical method. Globar molecular spectroscopic technique -attenuated total reflectance-ATR-FTIR spectroscopy will be used. For this research, feed type CDC Nasser, forage type CDC haymaker, and milling types CDC Arborg and Summit with three consecutive years are studied. There are three treatments for oat samples: Treatment 1, steam pressure processing alone; Treatment 2, adding innovative fibrolytic enzyme; Treatment 3, steam pressure processing plus fibrolytic enzyme. Each treatment combination has three replications. The objectives of this research are to detect the molecular structure spectral features of processed oat endosperm tissues at a molecular and cellular level in relation to chemical profiles, protein and carbohydrate fractions, energy profiles, degradation kinetics, intestinal digestibility, microbial protein production and true nutrient supply of whole oat grains. This research reveals the interactive association between induced molecular structure changes and nutrient properties and true nutrient supply. This research is also to increase economic returns to oat producers and related dairy industries through efficient utilization of feed-type or milling type of oat grains.

PSXIII-1 Effect of varieties and processing methods on physicochemical, nutritional, molecular structural characteristics of feed chickpeas

The objectives of this study were to evaluate the effect of varieties and heat processing methods on molecular structural, physicochemical, and nutritional characterization of feed chickpeas; evaluate the effect of heat processing methods, dry heat, wet heat and microwave irradiation processing method on feed chickpeas as an alternative source for protein and energy feed for ruminant livestock. To reveal the molecular structure spectral profile of chickpeas varieties and the molecular structure changes when applied heat processing methods, vibrational molecular spectroscopy was applied. Feed chickpea samples were determined for chemical profile, energy values, carbohydrate fractions. Subsequently, chickpea samples were incubated in the rumen of dairy cows for degradation kinetics analysis of nutrients. The intestinal digestion of feed chickpea samples was determined using three-step in vitro method with pre-incubation at 16h. Later, protein and carbohydrate related molecular spectral features before and after incubation were performed using vibrational ATR-FTIR molecular spectroscopy. The interactive relationship between processing induced molecular spectral profile changes and nutrient metabolism and availability were studied. The available results showed that varieties and heat processing methods significantly impacted molecular structural, physicochemical, and nutritional characterization of feed chickpeas.

[Prediction of the vaulting after posterior chamber intraocular lens implantation]

Objective: To investigate the influencing factors on the vaulting one month after implantable collamer lens (ICL) implantation, and to develop and verify a prediction formula. Methods: The first half of this study was retrospective case series study, and the second half was cross-sectional stydy. A total of 83 eyes of 83 patients who underwent ICL implantation in the Lixiang Eye Hospital of Soochow University were included in the first half of the study, with an average age of (27±5) years, from August 1, 2019 to December 30, 2019. All patients underwent a complete preoperative examination, including axis length, anterior chamber depth, comprehensive optometry, intraocular pressure, central corneal thickness, white-to-white diameter, horizontal and vertical sulcus-to-sulcus diameter (STS), crystalline lens thickness (LT), corneal curvature, and bright and dark pupil diameter. Multiple linear regression (stepwise) was used to develop a prediction formula. In the validation part, a total of 65 people (65 eyes) were included, with an average age of (26±5) years, from March 1, 2020 to June 1, 2020. The accuracy and reliability of the formula were verified by the intergroup correlation coefficient and Bland-Altman consistency test. Results: At 1 month after surgery, ICL size had the greatest impact on the vaulting (β=0.942, P<0.001), followed by horizontal STS (β=-0.517, P<0.001), LT (β=-0.376, P<0.001), and vertical STS (β=-0.257, P=0.017). The influence of other factors was not statistically significant (all P>0.05). The regression equation was as follows: the vaulting (μm)=-1 369.05+657.12×ICL size-287.41×horizontal STS-432.50×LT-137.33×vertical STS (the fitting degree R=0.813, R²=0.660, and corrected R²=0.643). In the verification part, the predicted average vaulting was (497.31±102.75) μm, while the actual vaulting was (514.62±152.99) μm. About 96.92% (63/65) of the patients were fitted in the moderate vault, and 3.08% (2/65) were in the high vault. The intergroup correlation coefficient was 0.581. According to the Bland-Altman test, the actual vaulting was 17.31 μm, higher than the predicted value, and the 95% confidence interval of the difference was -260.28 to 294.90 μm. Conclusion: The ICL size, horizontal and vertical STS and LT are the factors that affect and predict the vaulting one month after ICL implantation, and our prediction formula has good accuracy and reliability. (Chin J Ophthalmol, 2021, 57: 519-525).

Study of PWR hot leg creep rupture and RCS depressurization strategy during an SBO accident

Preventing the leakage of radioactive materials is important to nuclear safety. During a station blackout accident in pressurized water reactors, the hot leg creep rupture caused by hot leg countercurrent flow occurs before the reactor pressure vessel failure that caused by lower head rupture. The secondary fission products barrier is lost after hot leg creep rupture. An analysis for this phenomenon was done using the Modular Accident Analysis Program version 4.0.4 code. A station blackout accident for CPR1000 is simulated and the occurrence and influence of hot leg creep rupture phenomenon are analyzed in detail. After that, a sensitivity analysis of the opening of different pressurizer pilot-operated relief valves at five minutes after entering severe accident management guideline (before the hot leg creep rupture occurs) is studied. The results show that reactor pressure vessel failure time can be extended by at least 4 h if at least one pilot-operated relief valve is opened and direct containment heating phenomenon can be eliminated if at least two pilot-operated relief valves are opened.

Divergent responses of ecosystem water-use efficiency to extreme seasonal droughts in Southwest China

The recurrent drought extremes have resulted in deleterious impacts on ecological security. Despite that many attempts have been made to explore ecosystem responses to different severities of droughts, a deep understanding of how ecosystem water-use efficiency (WUE) responds to extreme seasonal droughts is critical for predicting the trends under future climate change, especially in the ecologically-fragile karst ecosystem across Southwest China. This study systematically examined the spatio-temporal variations of ecosystem WUE over the karst and non-karst areas, as well as their divergent responses to different seasonal droughts. Our findings revealed the apparent increase in drought frequency, duration, and severity in Southwest China during the past four decades. Meanwhile, spring and summer drought events were the prevailing drought types. Compared with the non-karst area, multi-year mean WUE in the karst area was relatively lower, whereas the area exhibiting significant increase in WUE (p < 0.01) accounted for 39.3% and 22.3%, respectively. However, the effects of drought on ecosystem WUE varied in different seasons with more severe consequence in the karst ecosystem. During the early stage of autumn-spring drought in 2009/2010, ecosystem WUE was apparently larger than the baseline condition with the difference turning to be negative anomalies during the peak period, whereas the effect of summer drought in 2011 led to negative anomalies nearly throughout the duration. Further analysis revealed that the anomalies in evapotranspiration acted a prominent role in altering WUE at the onset of both droughts, while ecosystem WUE was mainly determined by the sensitivity of gross primary production during the later stage. All analyses are beneficial for expecting the coupling relationship between global carbon and water cycles to future climate change, particularly as droughts are projected to increase in terms of frequency and severity.

[Cone-beam CT evaluation of the Monson's spherical radius of young adults in Guangdong]

Objective: To measure and analyze the spherical radius of Monson of normal young people in Guangdong province using cone-beam CT (CBCT), and to establish a personalized measurement method of the spherical radius of Monson to provide a reference for clinical application of Monson spherical radius in occlusal reconstruction. Methods: Sixty healthy young adults from physical examination population at Stomatology Hospital of Guangzhou Medical University [30 males and 30 females, aged (22.1±2.0) years 18-26 years) were recruited, and their CBCT were taken. Three-dimensional reconstruction of CBCT data was carried out, and the reconstructed models were fixed, traced and measured. The difference of Monson spherical radius between male and female was compared by using a single sample t-test. Results: The Monson spherical radius was (100.72±4.89) mm. The Monson spherical radius of male and female were (103.48±4.19) mm and (97.97±3.93) mm respectively. The difference between male and female was statistically significant (P<0.01). Conclusions: CBCT can be used to accurately measure the spherical radius of Monson and can be used as a reference for reconstruction of occlusal plane.

[Prevalence of CYP2C19 gene mutations in patients with coronary heart disease and its biological activation effect in clopidogrel antiplatelet response]

Objective: The purpose of this study was to investigate the effects of CYP2C19 gene mutations on clopidogrel antiplatelet activity in the patients with coronary heart disease treated by percutaneous coronary intervention. Methods: Patients with coronary heart disease, who hospitalized in the Second Affiliated Hospital of Nanchang University from March 2011 to June 2019, and healthy individuals with matching genetic background, gender, and age as controls were included in this study. Basic clinical data were analyzed and blood samples of all research subjects were obtained for extraction of DNA, and Sanger first-generation sequencing method was used to detect CYP2C19 gene mutation from full exon and exon and intron junction. CYP2C19 gene variations in patients with coronary heart disease were compared with the 1000 Genomes Browse database and the sequencing results of healthy controls to determine whether the gene variation was a genetic mutation or a genetic polymorphism. After that, PolyPhen-2 prediction software was used to analyze the harmfulness of gene mutations to predict the effect of mutations on protein function. The same dose of CYP2C19 wild-type plasmid and the CYP2C19 gene mutant plasmids were transfected into human normal liver cells HL-7702. After transfection of 24 h, the expression of CYP2C19 protease in each group was detected. The liver S9 protein was incubated with clopidogrel, acted on platelets to detect the platelet aggregation rate and the activity of human vasodilator-activated phosphoprotein (VASP). Results: A total of 1 493 patients with coronary heart disease (59.36%) were enrolled, the average age was (64.5±10.4) years old, of which 1 129 were male (75.62%). Meanwhile, 1 022 healthy physical examination volunteers (40.64%) were enrolled, and the average age was (64.1±11.0) years old, of which 778 were male (76.13%). A total of 5 gene mutations of CYP2C19 gene were identified in 12 patients (0.80%), namely, 4 known mutations T130K (1 case), M136K (6 cases), N277K (3 cases), V472I (1 case) and one new mutation G27V (1 case), no corresponding gene mutation was found in healthy controls. It was found that T130K and M136K were probably damaging, G27V was possibly damaging, and N277K and V472I were benign mutations. In vitro, we demonstrated that the platelet aggregation rate of the M136K gene mutation group was 24.83% lower than that of the wild type (59.58% vs. 34.75%; P<0.05), and the phosphorylated VASP level was 23.0% higher than that of the wild type (1.0 vs. 1.23; P<0.05). However, the platelet aggregation rate and phosphorylated VASP level were similar between of G27V, T130K, N277K, V472I gene mutation groups and wild type group (P>0.05). Conclusions: In this study, 5 gene mutations are defined in patients with coronary heart disease, namely G27V, T130K, M136K, N277K, V472I. In vitro functional studies show that CYP2C19 gene mutation M136K, as a gain-of-function gene mutation, can enhance the activation of CYP2C19 enzyme on clopidogrel, thereby inhibiting the platelet aggregation rate.

Cardiomyocyte-Restricted High-mobility group box 1 (HMGB1) deletion leads to small heart and inflammation through GR/PGC-1a signaling

 

Cardiomyocyte-Restricted High-mobility group box 1 (HMGB1) Deletion Leads to small heart and inflammation Through GR/PGC-1a signaling

Background

Cardiac growth and remodeling are key biological process influencing the physiological performance of the heart. Previous study showed critical role of intracellular HMGB1 in vitro. However, the in vivo study using conditional Hmgb1 ablation did not significantly affect the cellular and organic function.

Purpose

Previously we have demonstrated the extracellular effect of HMGB1 as a proinflammatory molecule on cardiac remodeling. Here, to elucidate the intracellular effect of HMGB1 on cardiac function in vivo, we perform the study.

Methods

Conditional genetic deletion of HMGB1 mouse was constructed using cTnT-Cre Hmgb1fl/fl. And then we detected body weight, and analyzed cardiac function of 12-week old mice using echocardiography. The subcelluar morphology was detected using the transmission electron microscopy (TEM) examination, and the changes of glycolipid metabolism was detected by the positron emission tomography (PET)/computed tomography (CT) imaging and GC-FID/MS analysis in heart tissue. And Then we used RNA-seq to find transcriptomic changes. And co-immunoprecipitation experiments, chromatin immunoprecipiptation (ChIP) were used to validate the binding of HMGB1 and glucocorticoid receptor (GR). The downstream signal changes were detected using western blot analysis. To validate the result, we further constructed the cardiac HMGB1 deficient mouse using Ckmm-Cre Hmgb1fl/fl, and measured body weight and cardiac function.

Results

We found HMGB1 deletion by cTnT-Cre in mouse hearts altered GR function, glycolipid metabolism, and eventually led to growth retardation, small heart, and heart failure. The subcelluar morphology didn't show significant change caused by HMGB1 knockout. The heart showed significantly elevation of glycolysis and free fatty acid deposition, and related enzyme changes. Transcriptomic analysis revealed a list of differential expressed genes, which coincide with the glucocorticoid receptor function in neonatal mice, and significant increase inflammatory genes of the adult ones. The cardiac HMGB1 knockout lead to a series changes of PGC-1a, UCP3, and glycerol kinase, which were the cause of metabolic change and further impact the cardiac function. And the Ckmm-Cre Hmgb1fl/fl mouse didn't show significant phenotype, which was consistent with the reported negative result of Cardiomyocyte-specific Hmgb1 deletion via MHC-Cre.

Conclusions

Therefore, our results demonstrated that HMGB1 plays an essential role in maintaining normal cardiac growth and function by regulating GR function and glycolipid metabolism. And the strikingly different phenotype from the cardiac-specific HMGB1-deficient mice may be caused by the cross with different Cre mouse.

Main results and graphic summary

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): National Natural Science Foundation of China

IGF-1R/β-catenin signaling axis is implicated in streptozotocin exacerbating bone impairment in ovariectomized rats

OBJECTIVE

The aim of this study was to investigate the role of the insulin-like growth factor-1 receptor (IGF-1R)/β-catenin signaling axis in bone impairment induced by hyperglycemia in ovariectomized rats.

METHODS

Rats were divided into four groups. The sham group received sham operation and a single intraperitoneal administration of vehicle. The ovariectomy (OVX) group was subjected to bilateral OVX and vehicle injection. The streptozotocin (STZ) group received sham operation and a single STZ injection to induce hyperglycemia. The OVX + STZ group received bilateral OVX and a single STZ injection. Dual-energy X-ray absorptiometry measurement, bone biomechanics test, micro-computed tomography scan, and hematoxylin-eosin staining were performed to evaluate bone alteration in this model. The expression of relevant signals including IGF-1R, glycogen synthase kinase-3β (GSK-3β), and β-catenin were examined by quantitative real-time polymerase chain reaction and western blot.

RESULTS

The OVX, STZ, and OVX + STZ groups induced bone loss, attenuated bone strength, and impaired microarchitecture compared with the sham group, respectively. Compared with OVX, more serious bone damage was found in the OVX + STZ group, which showed enhanced phosphorylation of IGF-1R, GSK-3β, and β-catenin.

CONCLUSION

OVX plus STZ induced more serious bone impairment than OVX alone, which involves the IGF-1R/β-catenin signaling axis in the pathogenesis. This may provide a potential target for treatment of postmenopausal diabetic osteoporosis.

AB0474 CAROTID CONTRAST ENHANCED ULTRASOUND IN CASES OF TAKAYASU ARTERITIS COMPLICATED WITH BEHCET’S DISEASE

Background:

Carotid contrast enhanced ultrasound (CEUS) is used for diagnosis and activity determination of patients with Takayasu’s arteritis (TA). However, very little is known about the carotid CEUS features of TA complicated with Behcet’s disease (BD).

Objectives:

This study reports the carotid CEUS features in cases of TA complicated with BD (TBD).

Methods:

A total of 10 carotid CEUS examinations were performed on 4 patients of TBD. 10 TA patients complicated with no rheumatoid disease were included as control group. For each carotid artery lesion, the carotid CEUS features was graded as follows: Grade 0, artery wall shows no microbubbles, Grade 1, artery wall shows limited or moderate microbubbles, Grade 2, artery wall shows severe microbubbles.

Results:

2/10 patients in TBD group has oral ulcer during the CEUS examination, while all the other patients included in our study showed no clinical symptoms related to active TA or BD. The carotid wall thickness was greater of CEUS grade 2 than grade 1 in both group(TBD: 2.62±0.74mm vs 1.66±0.22mm,p=0.001; TA:1.84±0.31mm vs 1.53±0.5mm,p=0.136). The carotid wall thickness was significantly greater in TBD group than TA group, but there was no significant differences between the two groups in clinical data and CEUS grade (table 1).

Table 1.

Clinical data and carotid CEUS features of both groups

TBDTApAge (year)32.5±3.4430.5±9.20.487Male320.605ESR (mm/h)4(2, 10)7(3.5, 11)0.406CRP (mg/L)6.42(0.55, 15.38)0.58(0.44, 5.05)0.168Wall thickness (mm)2.10±0.701.67±0.440.030CEUS grade 29120.527

Conclusion:

This study first shows carotid CEUS features in cases of TA complicated with BD, which may help with the comprehensive treatments of the disease.

Disclosure of Interests: :

None declared

Implication of Modified Chemical Profiles of Different Seed Proteins through Heat-Related Processing to Protein Nutrition and Metabolic Characteristics in Ruminant Systems

The objectives of this study were to reveal the implication of modified chemical profiles of protein in cool-season-adapted cereal seeds through heat-related processing to protein nutrition and metabolic characteristics in ruminant systems. The parameters of protein-related chemical and nutritive profiles modified by heat-related processing included (a) chemical and nutrient profiles, (b) degradation kinetics (K_d and BCP), (c) digestion (IDP and TDP), (d) degraded protein balance (DPB/OEB value), and (e) metabolizable protein (MP, DVE, and FMV values). The seeds used in this study included cool-season-adapted wheat (CSW), triticale (CST), and corn (CSC). Each grain source had 3 consecutive year-replicated samples and were subjected to different heat-related processing: dry heating (DH) and moist heating (MH). The results showed that (1) the heat-related processing significantly modified metabolic characteristics of protein in the seeds (p < 0.05), (2) in comparison to DH, MH had a dramatic improvement (p < 0.05) in protein utilization profiles (decreased rumen degradation and increased intestinal digestion), (3) the seeds had significant (p < 0.05) difference in rumen degradation and intestinal digestion, (4) among the seeds, the CSW had the highest milk value (FMV; p < 0.05) and was increased by MH application (p < 0.05), and (5) the results showed that the seeds responded independently to different heat-related processing. MH-related processing had a more profound impact on CSW and CST in chemical profiles and nutrition. The CSC had less response to the heat-related processing.

Remotely monitoring ecosystem respiration from various grasslands along a large-scale east-west transect across northern China

BACKGROUND

Grassland ecosystems play an important role in the terrestrial carbon cycles through carbon emission by ecosystem respiration (R_e) and carbon uptake by plant photosynthesis (GPP). Surprisingly, given R_e occupies a large component of annual carbon balance, rather less attention has been paid to developing the estimates of R_e compared to GPP.

RESULTS

Based on 11 flux sites over the diverse grassland ecosystems in northern China, this study examined the amounts of carbon released by R_e as well as the dominant environmental controls across temperate meadow steppe, typical steppe, desert steppe and alpine meadow, respectively. Multi-year mean R_e revealed relatively less CO₂ emitted by the desert steppe in comparison with other grassland ecosystems. Meanwhile, C emissions of all grasslands were mainly controlled by the growing period. Correlation analysis revealed that apart from air and soil temperature, soil water content exerted a strong effect on the variability in R_e, which implied the great potential to derive R_e using relevant remote sensing data. Then, these field-measured R_e data were up-scaled to large areas using time-series MODIS information and remote sensing-based piecewise regression models. These semi-empirical models appeared to work well with a small margin of error (R² and RMSE ranged from 0.45 to 0.88 and from 0.21 to 0.69 g C m^-2 d^-1, respectively).

CONCLUSIONS

Generally, the piecewise models from the growth period and dormant season performed better than model developed directly from the entire year. Moreover, the biases between annual mean R_e observations and the remotely-derived products were usually within 20%. Finally, the regional R_e emissions across northern China's grasslands was approximately 100.66 Tg C in 2010, about 1/3 of carbon fixed from the MODIS GPP product. Specially, the desert steppe exhibited the highest ratio, followed by the temperate meadow steppe, typical steppe and alpine meadow. Therefore, this work provides a novel framework to accurately predict the spatio-temporal patterns of R_e over large areas, which can greatly reduce the uncertainties in global carbon estimates and climate projections.

Infrared attenuated total reflection spectroscopic analysis and quantitative detection of forage spectral features in ruminant systems

This study aimed to (1) access protein molecular structure profile and metabolic characteristics of model forages [Foreign sourced-origin (coded as: "FSO", n = 7 vs. Chinese sourced-origin alfalfa hay "CSO", n = 5] in ruminant systems; (2) Quantify the relationship between forage protein molecular structures and protein utilization and availability. Advanced non-invasive vibrational molecular spectroscopic technique (ATR-FTIR: Attenuated Total Reflection Fourier Transform Infrared spectroscopy) with chemometrics was applied to reveal forage protein molecular structure. Both univariate and multivariate molecular spectral analyses were applied to study molecular structure features in model forages. The molecular structure study provided the detailed protein structure profiles of Amide I and Amide II areas and height, total Amide I and II area ratios, Amide I to II height ratio as well as Amide I to II area ratio using ATR-FTIR spectroscopy. The results showed FSO and CSO had similar (P > 0.05) protein rumen degradation kinetics. However, FSO had superior quality than CSO in intestinal (IDP) and total digestible protein (TDP) and truly absorbed nutrient supply (P < 0.05). As intestinal digestion of protein, FSO was higher (P < 0.05) in protein digestion in terms of: intestinal digestibility of rumen undegraded protein (dIDP: 47.5 vs. 38.3 %RUP); Intestinal digestible protein (IDP: 17.6 vs. 13.7 %CP). As truly absorbed nutrient supply, FSO contained higher (P < 0.05) truly absorbed rumen synthesized microbial protein, absorbable rumen undegradable feed protein in the small intestine, total truly digested protein in the small intestine, metabolizable protein and Feed Milk Value (FMV^DVE: 1.2 vs. 1.1 g/kg DM). The molecular structure-nutrition interactive relationship study showed that protein molecular structure profiles were highly associated to protein rumen degradation kinetics, significantly correlated to protein subfractions, protein intestinal digestion, and truly absorbed nutrient supply in ruminant systems.

[Analysis of electrocardiogram and blood related indicators in workers occupationally exposed to mercury in Jiangsu Province from 2016 to 2018]

Objective: To investigate the health status of occupational mercury workers and reveal the effects of mercury exposure on the cardiovascular system. Methods: In June 2019, a total of 2651 mercury workers participated in the occupational health examination between 2016-2018 from a thermometer manufacturing plant and a fluorescent lamp manufacturing plant were included in this study. Then, they were divided into a high-level mercury exposure group (425 workers whose urine mercury concentration >35 μg/g creatinine) and a low-mercury mercury exposure group (2226 workers whose urinary mercury concentration <35 μg/g creatinine) . Mercury concentration in the workplace was also detected. Finally, the results of electrocardiogram (ECG) , blood routine, blood biochemistry and other physical examinations were analyzed. The measurement data of age and exposure years were analyzed by test. Urinary mercury and blood parameters were analyzed by Mann-Whitney nonparametric test. Chi-square test was used for the analyses of gender, ECG abnormality rate and other categorical data. Results: The 8-hour weighted average allowable concentration (CTWA) of mercury in the workplace of high-exposure group was 0.002 2-0.152 mg/m(3). The abnormal rate of ECG in the high-exposed group (29.6%) was higher than that in the low-exposure group (10.1%) in 2018 (P<0.01) . Compared with the low-exposure group, the WBC of the high-exposure group from 2016 to 2018 was increased, with statistically significance (P<0.05) ; the RBC of the high-exposure group in 2016 and 2017 was decreased, with statistically significance (P<0.01) ; the total bilirubin concentration in the high-exposure group was decreased from 2016 to 2018, with statistically significance (P<0.05) . Conclusion: Long-term exposure to high concentration of mercury in the workplace may influence cardiovascular system. Therefore, engineering protection and individual protection should be implemented well.

The reduced lncRNA NKILA inhibited proliferation and promoted apoptosis of chondrocytes via miR-145/SP1/NF-κB signaling in human osteoarthritis

OBJECTIVE

Growing evidence has shown that long non-coding RNAs (lncRNAs) play some roles in the progression of osteoarthritis. In this study, we investigated the functions and mechanisms of lncRNA NKILA (NKILA) of chondrocytes in human osteoarthritis (OA).

PATIENTS AND METHODS

RT-PCR was used to detect the expressions of NKILA and miR-145 in OA tissues. After transfection of NKILA overexpression lentivirus (LV-NKILA) and NKILA downregulation lentivirus (LV-shNKILA) into primary chondrocytes, MTT assay was carried out to measure the cell proliferation of chondrocytes. The expressions of SP1, Bcl-2, Bax, cleaved caspase-3 and NF-κB signaling factors were detected by Western blot. Moreover, luciferase assay was performed to explore the binding site of NKILA and miR-145, miR-145 and SP1. Finally, JSH, a NF-κB signaling inhibitor, was added into chondrocytes transfected with LV-shNKILA or miR-145 mimic to detect that NKILA functions via miR-145/SP1/NF-κB signaling pathway.

RESULTS

We found that NKILA and SP1 were significantly reduced, miR-145 was increased in cartilage tissues of OA patients. After LV-NKILA transfection, the proliferation ability of chondrocytes was improved and cell apoptosis was inhibited; however, the proliferation ability of chondrocytes was repressed, and cell apoptosis was increased in LV-sh NKILA group. MiR-145 was predicted to be a potential target of NKILA and luciferase gene reporter assay confirmed that NKILA could directly bind with miR-145. Furthermore, SP1 was predicted to be a target gene of miR-145 and luciferase gene reporter assay proved that miR-145 could directly bind with SP1. Finally, we added JSH, a NF-κB signaling inhibitor, into chondrocytes with LV-shNKILA or miR-145 mimic. Results showed that the repressed SP1 was reversed after the addition of JSH in both LV-shNKILA and miR-145 mimic group. Further, the repressed proliferation capacities and promoted cell apoptosis were also reversed after the addition of JSH.

CONCLUSIONS

According to the results, this study uncovers NKILA is reduced in human osteoarthritic cartilage tissues. Furthermore, we firstly uncover that the reduced NKILA could function as a ceRNA to improve miR-145, which inhibited SP1 expression and regulated NF-κB signaling pathway, thereby promoting tissue inflammation, and inhibiting proliferation and promoting apoptosis of chondrocytes. Thus, it may be used as a promising prognostic marker and a potential target for osteoarthritis.