Study on exosomes for identifying bipolar disorder in early stage: A cross-sectional and validation study protocol.

BACKGROUND: The difficulty is remained to accurately distinguish bipolar disorder (BD) from major depressive disorder (MDD) in early stage, with a delayed diagnosis for 5-10 years. BD patients are often treated with antidepressants systematically due to being diagnosed with MDD, affecting the disease course and clinical outcomes. The current study aims to explore the role of plasma exosomes as biomarker to distinguish BD from MDD in early stage. METHODS: Two stages are included. The first stage is a cross-sectional study, comparing the concentrations of plasma exosome microRNA and related proteins among BD group, MDD group, and healthy controls (HC) group (n = 40 respectively), to identify target biomarkers preliminarily. The "Latent Class Analysis" and "Receiver Operating Characteristic" analysis will be performed to determine the optimal concentration range for each biomarker. The second stage is to validate target markers in subjects, coming from an ongoing study focusing on patients with a first depressive episode. All target biomarkers will be test in plasma samples reserved at the initial stage to detect whether the diagnosis indicated by biomarker level is consistent with the diagnosis by DSM-5. Furthermore, the correlation between specific biomarkers and the manic episode, suicidal ideation, and adverse reactions will also be observed. DISCUSSION: Exosome-derived microRNA and related proteins have potential in serving as a good medium for exploring mental disorders because it can pass through the blood-brain barrier bidirectionally and convey a large amount of information stably. Improving the early diagnosis of BD would help implement appropriate intervention strategy as early as possible and significantly reduce the burden of disease.

Dietary Supplementation of Tannic Acid Promotes Performance of Beef Cattle via Alleviating Liver Lipid Peroxidation and Improving Glucose Metabolism and Rumen Fermentation.

This study aimed to investigate the effects of dietary tannic acid (TAN) on the gas production, growth performance, antioxidant capacity, rumen microflora, and fermentation function of beef cattle through in vitro and in vivo experiments. TAN was evaluated at 0.15% (dry matter basis, DM) in the in vitro experiment and 0.20% (DM basis) in the animal feeding experiment. The in vitro results revealed that compared with control (CON, basal diet without TAN), the addition of TAN significantly increased the cumulative gas production and asymptotic gas production per 0.20 g dry matter substrate (p < 0.01), with a tendency to reduce methane concentration after 96 h of fermentation (p = 0.10). Furthermore, TAN supplementation significantly suppressed the relative abundance of Methanosphaera and Methanobacteriaceae in the fermentation fluid (LDA > 2.50, p < 0.05). The in vivo experiment showed that compared with CON, the dietary TAN significantly improved average daily gain (+0.15 kg/d), dressing percent (+1.30%), net meat percentage (+1.60%), and serum glucose concentration (+23.35%) of beef cattle (p < 0.05), while it also significantly reduced hepatic malondialdehyde contents by 25.69% (p = 0.02). Moreover, the TAN group showed significantly higher alpha diversity (p < 0.05) and increased relative abundance of Ruminococcus and Saccharomonas (LDA > 2.50, p < 0.05), while the relative abundance of Prevotellaceae in rumen microbial community was significantly decreased (p < 0.05) as compared to that of the CON group. In conclusion, the dietary supplementation of TAN could improve the growth and slaughter performance and health status of beef cattle, and these favorable effects might be attributed to its ability to alleviate liver lipid peroxidation, enhance glucose metabolism, and promote a balanced rumen microbiota for optimal fermentation.

Effects of Heated Drinking Water during the Cold Season on Serum Biochemistry, Ruminal Fermentation, Bacterial Community, and Metabolome of Beef Cattle.

This study explored the effects of drinking heated water in the cold seasons on the serum metabolism, rumen microbial fermentation, and metabolome of beef cattle. Twelve fattening cattle (642 ± 14.6 kg) aged 21 to 22 months were randomly and equally divided into two groups based on body weight: one receiving room-temperature water (RTW; average 4.39 ± 2.55 °C) and the other heated water (HW; average 26.3 ± 1.70 °C). The HW group displayed a significant decrease in serum glucose (p < 0.01) and non-esterified fatty acid (p < 0.01), but increases in insulin (p = 0.04) and high-density lipoprotein (p = 0.03). The rumen fermentation parameters of the HW group showed substantial elevations in acetate (p = 0.04), propionate (p < 0.01), isobutyrate (p = 0.02), and total volatile fatty acids (p < 0.01). Distinct bacterial composition differences were found between RTW and HW at the operational taxonomic unit (OTU) level (R = 0.20, p = 0.01). Compared to RTW, the HW mainly had a higher relative abundance of Firmicutes (p = 0.07) at the phylum level and had a lower abundance of Prevotella (p < 0.01), norank_f_p-215-o5 (p = 0.03), and a higher abundance of NK4A214_group (p = 0.01) and Lachnospiraceae_NK3A20_group (p = 0.05) at the genus level. In addition, NK4A214_group and Lachnospiraceae_NK3A20_group were significantly positively correlated with the rumen propionate and isovalerate (r > 0.63, p < 0.05). Prevotella was negatively correlated with rumen propionate and total volatile fatty acids (r = -0.61, p < 0.05). In terms of the main differential metabolites, compared to the RTW group, the expression of Cynaroside A, N-acetyl-L-glutamic acid, N-acetyl-L-glutamate-5-semialdehyde, and Pantothenic acid was significantly upregulated in HW. The differentially regulated metabolic pathways were primarily enriched in nitrogen metabolism, arginine biosynthesis, and linoleic acid metabolism. Prevotella was significantly positively correlated with suberic acid and [6]-Gingerdiol 3,5-diacetate (r > 0.59, p < 0.05) and was negatively correlated with Pantothenic acid and isoleucyl-aspartate (r < -0.65, p < 0.05). NK4A214_group was positively correlated with L-Methionine and glycylproline (r > 0.57, p < 0.05). Overall, our research demonstrates the important relationship between drinking water temperature and metabolic and physiological responses in beef cattle. Heating drinking water during cold seasons plays a pivotal role in modulating internal energy processes. These findings underscore the potential benefits of using heated water as a strategic approach to optimize energy utilization in beef cattle during the cold seasons.

Heating Drinking Water in Cold Season Improves Growth Performance via Enhancing Antioxidant Capacity and Rumen Fermentation Function of Beef Cattle.

The research aimed to investigate the suitable drinking water temperature in winter and its effect on the growth performance, antioxidant capacity, and rumen fermentation function of beef cattle. A total of 40 beef cattle (640 ± 19.2 kg) were randomly divided into five treatments with eight cattle in each treatment raised in one pen according to initial body weight. Each treatment differed only in the temperature of drinking water, including the room-temperature water and four different heat water groups named RTW, HW_1, HW_2, HW_3, and HW_4. The measured water temperatures were 4.39 ± 2.546 °C, 10.6 ± 1.29 °C, 18.6 ± 1.52 °C, 26.3 ± 1.70 °C, and 32.5 ± 2.62 °C, respectively. The average daily gain (ADG) showed a significant linear increase during d 0 to 60 and a quadratic increase during d 31 to 60 with rising water temperature (p < 0.05), and the highest ADG of 1.1911 kg/d was calculated at a water temperature of 23.98 °C (R2 = 0.898). The average rectal temperature on d 30 (p = 0.01) and neutral detergent fiber digestibility (p < 0.01) increased linearly with increasing water temperature. Additionally, HW_2 reduced serum triiodothyronine, thyroxine, and malondialdehyde (p < 0.05), and increased serum total antioxidant capacity (p < 0.05) compared with RTW. Compared with HW_2, RTW had unfavorable effects on ruminal propionate, total volatile fatty acids, and cellulase concentrations (p < 0.05), and lower relative mRNA expression levels of claudin-4 (p < 0.01), occludin (p = 0.02), and zonula occludens-1 (p = 0.01) in the ruminal epithelium. Furthermore, RTW had a higher abundance of Prevotella (p = 0.04), Succinivibrionaceae_UCG-002 (p = 0.03), and Lachnospiraceae_UCG-004 (p = 0.03), and a lower abundance of Bifidobacteriaceae (p < 0.01) and Marinilabiliaceae (p = 0.05) in rumen compared to HW_2. Taken together, heated drinking water in cold climates could positively impact the growth performance, nutrient digestibility, antioxidant capacity, and rumen fermentation function of beef cattle. The optimal water temperature for maximizing ADG was calculated to be 23.98 °C under our conditions. Ruminal propionate and its producing bacteria including Prevotella, Succinivibrionaceae, and Lachnospiraceae might be important regulators of rumen fermentation of beef cattle drinking RTW under cold conditions.

Recognizing schizophrenia using facial expressions based on convolutional neural network.

OBJECTIVE: Facial expressions have been served as clinical symptoms to convey mental conditions in psychiatry. This paper proposes to recognize patients with schizophrenia (SCZ) using their facial images based on deep learning algorithm, and to investigate objective differences in facial expressions between SCZ patients and healthy controls using deep learning algorithm and statistical analyses. METHODS: The study consists of two parts. The first part recruited 106 SCZ patients and 101 healthy controls, and videotaped their facial expressions through a fixed experimental paradigm. The video data were randomly divided into two sets, one for training a convolutional neural network (CNN) with the classification of "healthy control" or "SCZ patient" as output and the other for evaluating the classification result of the trained CNN. In the second part, all facial images of the recruited participants were put into another CNN separately, which was priorly trained with a facial expression database and will output the most likely facial expressions of the recruited participants. Statistical analyses were performed on the obtained facial expressions to find out the objective differences in facial expressions between the two recruited groups. RESULTS: The trained CNN achieved an overall accuracy of 95.18% for classifying "healthy control" or "SCZ patient." Statistical results on the obtained facial expressions demonstrated that the objective differences between the two recruited groups were statistically significant (p < .05). CONCLUSIONS: Facial expressions hold great promise as SCZ clues with the help of deep learning algorithm. The proposed approach would be potentially applied to mobile devices for autorecognizing SCZ in the context of clinical and daily life.

Precipitation and potential evapotranspiration determine the distribution patterns of threatened plant species in Sichuan Province, China.

A fundamental goal of ecologists is to determine the large-scale gradients in species richness. The threatened plants are the priority of such studies because of their narrow distribution and confinement to a specific habitat. Studying the distribution patterns of threatened plants is crucial for identifying global conservation prioritization. In this study, the richness pattern of threatened plant species along spatial and elevation gradients in Sichuan Province of China was investigated, considering climatic, habitat-heterogeneity (HHET), geometric constraint and human-induced factors. The species richness pattern was analyzed, and the predictor variables, including mean annual temperature (MAT), mean annual precipitation (MAP), potential evapotranspiration (PET), HHET, and disturbance (DIST), to species richness were linked using the geographical distribution data of threatened species compiled at a spatial resolution of 20 km × 20 km. Generalized linear models and structural equation modelling were used to determine the individual and combined effects of each variable on species richness patterns. Results showed a total of 137 threatened plant species were distributed between 200 and 4800 m.a.s.l. The central region of the province harbors the highest species diversity. MAP and PET profoundly explained the richness pattern. Moreover, the significant role of DIST in the richness patterns of threatened plants was elucidated. These findings could help determine the richness pattern of threatened plant species in other mountainous regions of the world, with consideration of the impact of climate change.

Long non-coding RNA DUXAP8 promotes tumorigenesis by regulating IGF1R via miR-9-3p in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide with a low 5-year survival rate. Long non-coding RNA (lncRNA) double homeobox A pseudogene 8 (DUXAP8) is an oncogene and a potential biomarker in various tumors, such as ovarian, colorectal and non-small-cell lung cancer. However, the function and molecular mechanism underlying DUXAP8 in HCC progression is not completely understood. The expression of DUXAP8, microRNA (miR)-9-3p and insulin-like growth factor 1 receptor (IGF1R) in HCC tissues and cells was detected via reverse transcription-quantitative PCR. The expression levels of IGF1R and epithelial-mesenchymal transition-associated proteins (Snail, Slug, E-cadherin, N-cadherin and vimentin) were assessed via western blotting. The effects of DUXAP8, miR-9-3p and IGF1R on proliferation, migration and invasion were examined by conducting Cell Counting Kit-8 and Transwell assays, respectively. The interaction between miR-9-3p and DUXAP8 or IGF1R was predicted using StarBase or TargetScan, and further assessed using dual luciferase reporter and RNA immunoprecipitation assays. DUXAP8 and IGF1R were upregulated and miR-9-3p was downregulated in HCC tissues and cells compared with adjacent healthy tissues and a normal liver cell line, respectively. miR-9-3p overexpression decreased the protein expression level of IGF1R, and miR-9-3p knockdown enhanced the protein expression level of IGF1R in HCC cells compared with the corresponding control groups. Moreover, compared with the corresponding control groups, DUXAP8 knockdown and miR-9-3p overexpression increased E-cadherin protein expression levels, and decreased Snail, Slug, N-cadherin and vimentin protein expression levels. However, miR-9-3p inhibitor and IGF1R overexpression reversed DUXAP8 knockdown- and miR-9-3p overexpression-induced effects, respectively. In addition, compared with the corresponding control groups, DUXAP8 knockdown and miR-9-3p overexpression suppressed proliferation, migration and invasion, which was reversed by miR-9-3p inhibitor and IGF1R overexpression, respectively. Moreover, miR-9-3p as the target of DUXAP8 and IGF1R as the target of miR-9-3p were verified in HCC cells. lncRNA DUXAP8 contributed to HCC tumorigenesis via the miR-9-3p/IGF1R axis, providing a novel therapeutic approach for HCC diagnosis and treatment.

Graphitic Encapsulation and Electronic Shielding of Metal Nanoparticles to Achieve Metal-Carbon Interfacial Superlubricity.

Presently, approaches to achieve superlubricity for diamond-like carbon (DLC) films rely heavily on the film deposition techniques and parameters, such as other nonmetallic element incorporation and structure optimization. In this work, we report a new feasible pathway to achieve superlubricity for DLC films, which is not dependent on the film preparation parameters but rather on the external effects, i.e., sliding interfacial addition of metal nanoparticles (Cu and Ni). The approach controls the structures of wear products by the introduction of metal nanoparticles and the subsequent effect of metal catalysts, to in situ form graphene-coated particles without impacting the overall performances of the films. Through detailed experimental investigations combined with density functional theory (DFT) simulations, graphitic encapsulation and electronic shielding of metal nanoparticles are responsible for the dramatic changes at the frictional interface leading to metal-carbon interfacial superlubricity. We expect that the approach will enrich the understanding of the lubrication mechanism of DLC films and promote the DLC films' superlubricity toward applications.

Diagnostic Value of Plasma miR-181b, miR-196a, and miR-210 Combination in Pancreatic Cancer.

PURPOSE: This study was aimed at investigating the roles of plasma miR-181b, miR-196a, and miR-210 in the diagnosis of pancreatic cancer (PC). METHODS: Plasma samples were isolated from 40 patients with PC and 40 healthy individuals, respectively. The expression of miR-181b, miR-196a, and miR-210 was detected by qRT-PCR. The level of carbohydrate antigen 199 (CA199) was measured by an electrochemiluminescence (ECL) assay. The receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of miR-181b, miR-196a, miR-210, CA199, and their combinations in PC. RESULTS: The expression of plasma miR-181b, miR-196a, and miR-210 was significantly upregulated in PC patients. The plasma level of CA199 was also significantly increased in PC patients. The expression of miR-181b, miR-196a, and miR-210 was closely associated with lymph node metastasis, clinical stage, and vascular invasion but not correlated with age, gender, and tumor size. miR-181b, miR-196a, and miR-210 have lower AUC than CA199 in the diagnosis of PC. miR-181b+miR-210 and miR-196a+miR-210 also have lower AUC than CA199. It is worth noting that miR-181b+miR-196a+miR-210 has a higher AUC than CA199 in the diagnosis of PC. CONCLUSION: The combination of plasma miR-181b, miR-196a, and miR-210 had a good diagnostic value for PC.

Carbon dots derived from flax straw for highly sensitive and selective detections of cobalt, chromium, and ascorbic acid.

Fluorescent detections of cobalt, chromium, and ascorbic acid by carbon dots are of importance for human health and environment. Green synthesis of fluorescent carbon dots from biomass is essential for their sustainable applications. Herein, carbon dots were successfully prepared by a simple hydrothermal method using flax straw as carbon source. The obtained carbon dots possess a much higher quantum yield (20.7%) and excitation-dependent photoluminescence behavior. The "on-off" fluorescence principle, quenching of the fluorescence intensity of the carbon dots in the presence of Co2+ or Cr6+ based on static quenching effect and inner filter effect, is extended to "on-off-on" principle for detection of ascorbic acid based on the reduction of Cr6+ to Cr3+ by ascorbic acid. The linear ranges for detections of Co2+, Cr6+, and ascorbic acid are 0-500, 0.5-80, and 0-200 µM, and the limits of the corresponding detections are 0.38, 0.19, and 0.35 µM, respectively. Compared with most reported fluorescence detections, our linear ranges are significantly wider and our detection limits are much lower for the detections of Co2+, Cr6+, and ascorbic acid. This sensing platform is highly sensitive and selective to monitor Co2+ and Cr6+ in real water and ascorbic acid in vitamin C tablets with remarkable practicality.

LncRNA HCP5 Regulates Pancreatic Cancer Progression by miR-140-5p/CDK8 Axis.

Background: Pancreatic cancer (PC) is a leading cause of cancer-related deaths worldwide. Human leukocyte antigen complex P5 (HCP5), a member of long noncoding RNAs (lncRNAs), was reported to be associated with the poor prognosis of PC. However, the mechanism of HCP5 in regulating the progression of PC remains poorly defined. Materials and Methods: Quantitative real-time polymerase chain reaction was performed to detect the expression levels of HCP5, microRNA (miR)-140-5p, and cyclin-dependent kinase 8 (CDK8) in PC tissues and cells. Cell counting kit-8 (CCK-8) assay was utilized to check cell proliferation. Transwell assay was employed to evaluate the abilities of cell migration and invasion. Xenograft tumor model was established to investigate the biological role of HCP5 in PC in vivo. The interaction between miR-140-5p and HCP5 or CDK8 was predicted by starBase or TargetScan, respectively. The dual-luciferase reporter assay was conducted to corroborate the interaction. The protein level of CDK8 was measured by Western blot. Results: HCP5 and CDK8 were significantly upregulated in PC tissues and cells, opposite to the expression of miR-140-5p. High expression of HCP5 contributed to the low survival rate and HCP5 silencing inhibited proliferation, migration, and invasion of PC cells in vitro. Simultaneously, in vivo experiments indicated that downregulation of HCP5 suppressed tumor growth. In addition, miR-140-5p was a target of HCP5 and bound to the 3'-untranslated region (3'UTR) of CDK8. Further studies revealed that overexpression of CDK8 reversed the miR-140-5p-mediated inhibitory effect on PC progression. Moreover, downregulation of miR-140-5p or upregulation of CDK8 inverted the silencing-mediated repressive impact of HCP5 on PC progression. Conclusion: Downregulation of HCP5 impeded PC progression by downregulating CDK8 via sponging miR-140-5p.

Comment on "High-surface-area corundum by mechanochemically induced phase transformation of boehmite".

Amrute et al (Reports, 25 October 2019, p. 485) claimed that no methods were able to produce high-purity α-Al2O3 with surface areas greater than 100 m2 g-1, even though much higher surface areas up to 253 m2 g-1 have been reported. Moreover, the materials they obtained could be porous aggregates and may not be 13-nm nanoparticles, as claimed.

Liver disease screening based on densely connected deep neural networks.

Liver disease is an important public health problem. Liver Function Tests (LFT) is the most achievable test for liver disease diagnosis. Most liver diseases are manifested as abnormal LFT. Liver disease screening by LFT data is helpful for computer aided diagnosis. In this paper, we propose a densely connected deep neural network (DenseDNN), on 13 most commonly used LFT indicators and demographic information of subjects for liver disease screening. The algorithm was tested on a dataset of 76,914 samples (more than 100 times of data than the previous datasets). The Area Under Curve (AUC) of DenseDNN is 0.8919, that of DNN is 0.8867, that of random forest is 0.8790, and that of logistic regression is 0.7974. The performance of deep learning models are significantly better than conventional methods. As for the deep learning methods, DenseDNN shows better performance than DNN.

Robust and Antibacterial Polymer/Mechanically Exfoliated Graphene Nanocomposite Fibers for Biomedical Applications.

With the increasing demand for composites of multifunctional and integrated performance, graphene-based nanocomposites have been attracting increasing attention in biomedical applications because of their outstanding physicochemical properties and biocompatibility. High product yields and dispersion of graphene in the preparation process of graphene-based nanocomposites have long been a challenge. Further, the mechanical properties and biosafety of final nanocomposites are very important for real usage in biomedical applications. Here, we presented a novel high-throughput method of graphene on mechanical exfoliation in a natural honey medium, and a yield of ∼91% of graphene nanoflakes can be easily achieved with 97.76% of single-layer graphenes. The mechanically exfoliated graphene (MEG) can be well-dispersed in the poly(vinyl alcohol) (PVA) matrix. The PVA/MEG nanocomposite fibers are obtained by gel spinning and stretched 20 times. As a candidate for monofilament sutures, the PVA/MEG nanocomposite fibers with 0.3 wt % of MEG have an ultrahigh ultimate tensile strength of 2.1 GPa, which is far higher than that of the neat PVA fiber (0.75 GPa). In addition, the PVA/MEG nanocomposite fibers also have antibacterial property, low cytotoxicity, and other properties. On the basis of the above-mentioned properties, the effects of a common surgical suture and PVA/MEG nanocomposite fibers on wound healing are evaluated. As a result, the wounds treated with PVA/MEG nanocomposite fibers with 0.3 wt % of MEG show the best healing after 5 days of surgery. It is possible that this novel surgical suture will be available in the market relying on the gentle, inexpensive method of obtaining nonoxidized graphene and the simple process of obtaining nanocomposite fibers.

The enhancement of photocatalytic performance of SrTiO3 nanoparticles via combining with carbon quantum dots.

Carbon quantum dots were prepared by a simple chemical process using activated carbon as carbon source. The as-prepared carbon quantum dots are fine with a narrow size distribution and show excellent hydrophilicity. The carbon quantum dots were combined with SrTiO3 nanoparticles through a simple impregnation process to obtain a carbon quantum dots/SrTiO3 nanocomposite. The photocatalytic reaction rate of carbon quantum dots/SrTiO3 nanocomposite is about 5.5 times as large as that of pure SrTiO3 in the degradation of rhodamine B under sunlight irradiation. The enhanced performance in the degradation of rhodamine B may be attributed to the interfacial transfer of photogenerated electrons from SrTiO3 to carbon quantum dots, leading to effective charge separation in SrTiO3. Carbon quantum dots show potential applications in high-efficiency photocatalyst design.

Synthesis and luminescence characterization of a new yellowish-orange phosphor: Ba2 B10 O17 :Sm3.

A new yellowish-orange emitting phosphor, Ba2 B10 O17 :Sm3+ for use as a white light-emitting diode (W-LED) was synthesized by a solid-state reaction method. The X-ray diffraction results indicated that a pure Ba2 B10 O17 material was obtained. As a potential yellowish-orange luminescent material for W-LEDs, the Ba2 B10 O17 :Sm3+ phosphor could be excited effectively by near-ultraviolet (n-UV) light and exhibited yellowish-orange emission centered at 560 nm corresponding to the 4 G5/2  â†’ 6 H5/2 transition of Sm3+ ions. The optimum concentration of Sm3+ ions in Ba2 B10 O17 , critical transfer distance (Ra) and concentration quenching mechanism of the presented phosphor were investigated. Moreover, CIE chromaticity coordinates and color purity performance of the Ba2 B10 O17 :Sm3+ phosphor were also discussed. The present work suggests that the Ba2 B10 O17 :Sm3+ phosphor has potential as a type of yellowish-orange emitting phosphor. Copyright © 2016 John Wiley & Sons, Ltd.

Four-state memory based on a giant and non-volatile converse magnetoelectric effect in FeAl/PIN-PMN-PT structure.

We report a stable, tunable and non-volatile converse magnetoelectric effect (ME) in a new type of FeAl/PIN-PMN-PT heterostructure at room temperature, with a giant electrical modulation of magnetization for which the maximum relative magnetization change (ΔM/M) is up to 66%. The 109° ferroelastic domain switching in the PIN-PMN-PT and coupling with the ferromagnetic (FM) film via uniaxial anisotropy originating from the PIN-PMN-PT (011) surface are the key roles in converse ME effect. We also propose here a new, four-state memory through which it is possible to modify the remanent magnetism state by adjusting the electric field. This work represents a helpful approach to securing electric-writing magnetic-reading with low energy consumption for future high-density information storage applications.

Detachment of secondary dendrite arm in a directionally solidified Sn-Ni peritectic alloy under deceleration growth condition.

In order to better understand the detachment mechanism of secondary dendrite arm during peritectic solidification, the detachment of secondary dendrite arm from the primary dendrite arms in directionally solidified Sn-36at.%Ni peritectic alloys is investigated at different deceleration rates. Extensive detachment of secondary dendrite arms from primary stem is observed below peritectic reaction temperature TP. And an analytical model is established to characterize the detachment process in terms of the secondary dendrite arm spacing λ2, the root radius of detached arms and the specific surface area (SV) of dendrites. It is found that the detachment mechanism is caused by not only curvature difference between the tips and roots of secondary branches, but also that between the thicker secondary branches and the thinner ones. Besides, this detachment process is significantly accelerated by the temperature gradient zone melting (TGZM) effect during peritectic solidification. It is demonstrated that the reaction constant (f) which is used to characterize the kinetics of peritectic reaction is crucial for the determination of the detachment process. The value of f not only changes with growth rate but also with solidification time at a given deceleration rate. In conclusion, these findings help the better understanding of the detachment mechanism.

Role of Presepsin for the Assessment of Acute Cholangitis Severity.

BACKGROUND: Presepsin is a new emerging inflammatory biomarker. The primary purpose of this study was to elucidate the predictive usability of presepsin for severity assessment in patients with acute cholangitis (AC). METHODS: A total of 119 treatment-naive patients with AC (64 males, 55 females) were enrolled in this study. Patients were classified with Grade I (mild), Grade II (moderate), or Grade III (severe) AC based on severity assessment guidelines. Presepsin concentrations were measured on admission. RESULTS: The median presepsin concentrations were 297 pg/mL (interquartile range (IQR) 234 - 386 pg/mL), 590 pg/mL (IQR 559 - 619 pg/mL), and 857 pg/mL (IQR 740 - 960 pg/mL) in patients with mild, moderate, and severe AC, respectively. Presepsin concentrations were significantly higher in patients with severe AC than in patients with moderate AC (p < 0.01), and in patients with moderate AC than in patients with mild AC (p < 0.01). With the receiver operating characteristic (ROC) analysis, the areas under the curves (AUCs) for presepsin to discriminate patients with moderate and severe AC were 0.935 (95% confidence interval (CI) 0.877 to 0.993, p < 0.001) and 0.942 (95% CI 0.885 to 0.998, p < 0.001), respectively. CONCLUSIONS: Compared with other conventional biochemical indicators such as WBC, CRP, and PCT, presepsin may be a useful parameter for the severity assessment of AC.

On oscillatory microstructure during cellular growth of directionally solidified Sn-36at.%Ni peritectic alloy.

An oscillatory microstructure has been observed during deep-cellular growth of directionally solidified Sn-36at.%Ni hyperperitectic alloy containing intermetallic compounds with narrow solubility range. This oscillatory microstructure with a dimension of tens of micrometers has been observed for the first time. The morphology of this wave-like oscillatory structure is similar to secondary dendrite arms, and can be observed only in some local positions of the sample. Through analysis such as successive sectioning of the sample, it can be concluded that this oscillatory microstructure is caused by oscillatory convection of the mushy zone during solidification. And the influence of convection on this oscillatory microstructure was characterized through comparison between experimental and calculations results on the wavelength. Besides, the change in morphology of this oscillatory microstructure has been proved to be caused by peritectic transformation during solidification. Furthermore, the melt concentration increases continuously during solidification of intermetallic compounds with narrow solubility range, which helps formation of this oscillatory microstructure.